Sample records for aprons wharves

  1. 33 CFR 127.103 - Piers and wharves. (United States)


    ...) WATERFRONT FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.103 Piers and wharves. (a) If the...

  2. Sinopec Invests Heavily for Pipelines, Wharves to Increase Efficiency

    Institute of Scientific and Technical Information of China (English)


    @@ Sinopec recently said that it would earmark less than 8 billion yuan (US$966.2 million) to complete construction of two pipelines and three wharves by 2006 to improve its downstream operating efficiency.

  3. Crude Imports Triggers Investment Fever of Oil Wharves in China

    Institute of Scientific and Technical Information of China (English)


    @@ China's record high crude import of 80 million tons in 2003 has triggered a fever of oil wharf construction along the country's eastern coastal regions. Reportedly, the coastal harbor cities, such as Dalian, Tianjin, Qingdao, Nantong, Ningbo,Zhoushan, Maoming and Zhanjiang, have stepped up the efforts for construction of wharves, the large-scale berths for oil products in particular, so as to stimulate the rapid development of the local petrochemical and commodity flow industries.

  4. Defects in new protective aprons

    Energy Technology Data Exchange (ETDEWEB)

    Glaze, S.; LeBlanc, A.D.; Bushong, S.C.


    Upon careful examination, several defects have been detected in new protective aprons. The nature of the defects is identified and described. Although the occurrence of such defects has not exceeded 5%, they are significant enough to warrant return of the lead apron to the supplier. It is recommended that the integrity of all new protective aprons be verified upon receipt as well as at yearly intervals.

  5. Probabilistic Assessment for Seismic Performance of Pile-Supported Wharves

    Directory of Open Access Journals (Sweden)

    Hamid Heidary Torkamani


    Full Text Available The main objective of this study is to investigate the influence of uncertainties associated with the material properties on the seismic performance of pile-supported wharves. For this purpose a two-dimensional finite difference model, representing typical pile-supported wharf structures from western United States has been constructed using software FLAC2D. Incremental dynamic analysis has been applied to evaluate the response of wharf structure under different levels of seismic loading. The uncertainties at both structural and geotechnical parameters have been investigated using a tornado diagram and a first-Order Second-Moment (FOSM analysis. It has been found that the uncertainties at the dead load of structure, friction angle of rock fill and the porosity of rock fill contribute most to the variability of the displacement ductility factor of the pile-supported wharf structures. Based on the results, design considerations have been provided.

  6. APRON: A Cellular Processor Array Simulation and Hardware Design Tool

    Directory of Open Access Journals (Sweden)

    David R. W. Barr


    Full Text Available We present a software environment for the efficient simulation of cellular processor arrays (CPAs. This software (APRON is used to explore algorithms that are designed for massively parallel fine-grained processor arrays, topographic multilayer neural networks, vision chips with SIMD processor arrays, and related architectures. The software uses a highly optimised core combined with a flexible compiler to provide the user with tools for the design of new processor array hardware architectures and the emulation of existing devices. We present performance benchmarks for the software processor array implemented on standard commodity microprocessors. APRON can be configured to use additional processing hardware if necessary and can be used as a complete graphical user interface and development environment for new or existing CPA systems, allowing more users to develop algorithms for CPA systems.

  7. Usefulness of non-lead aprons in radiation protection for physicians performing interventional procedures. (United States)

    Zuguchi, Masayuki; Chida, Koichi; Taura, Masaaki; Inaba, Yohei; Ebata, Ayako; Yamada, Shogo


    At present, interventional radiology (IVR) tends to involve long procedures (long radiation duration), and physicians are near to the source of scattered radiation. Hence, shielding is critical in protecting physicians from radiation. Protective aprons and additional lead-shielding devices, such as tableside lead drapes, are important means of protecting the physician from scattered radiation. The purpose of this study was to evaluate whether non-lead aprons are effective in protecting physicians from radiation during IVR procedures. In this study, the radiation protection effects of commercially available protective lead and non-lead aprons, when exposed to diagnostic X rays, are compared. The performance of these non-lead and lead aprons was similar for scattered X rays at tube voltages of 60-120 kV. Properly designed non-lead aprons are thus more suitable for physicians because they weigh approximately 20% less than the lead aprons, and are non-toxic.

  8. Z Specification of Gate and Apron Control Management at Airport

    Directory of Open Access Journals (Sweden)

    Nazir Ahmad Zafar


    Full Text Available Modelling of an air traffic control (ATC system is an open issue and has become a challenging problem due to its complexity and increase of traffic at airports and in airspace. Consequently, automated ATC systems are suggested to improve efficiency ensuring the safety standards. It is reported that the number of collisions that occurred at airports surface is three times larger than in airspace. Further, it is observed that gates and aprons congestions cause significant delays at airports; hence, effective monitoring and guidance mechanisms are required to control ground air traffic. In this paper, formal procedure of managing air traffic from gate to enter in the active area of airport for taxiing is provided using Z notation. An integration of gate and apron controllers is described to manipulate the information for correct decision making and flow management. Graph theory is used for representation of airport topology and appropriate routs. In static part of the model, safety properties are described in terms of invariants over the critical data types. In dynamic model, the state space is updated by defining pre- and postconditions ensuring the safety. Formal specification is analysed using Z/Eves tool.

  9. Episodic Late Quaternary slopewash deposition as recorded in colluvial aprons, Southeastern Wyoming (United States)

    Hanson, Paul R.; Mason, Joseph A.; Goble, Ronald J.


    Colluvial aprons found along fluvial terraces of the Laramie River and Sybille Creek in southeastern Wyoming are interpreted as late Quaternary slopewash deposits. Each apron studied contained multiple buried soils, interpreted to indicate that slopewash activity was episodic and short-lived, and was followed by relatively long periods of landscape stability and soil development. Apron deposits were described and subsequently correlated based on their internal stratigraphy and their relative degree of soil development. Optical dating was used to chronologically constrain periods of slopewash deposition, and based on 17 optical ages taken from five aprons, aggradation occurred at ˜65-56, 16.0, 12.9, 11.8, 8.1, 7.3, 5.0, and 1.7 ka. Several of these events correspond with climatic transitions such as the termination of Heinrich Event 1, the onset and termination of the Younger Dryas, and the 8.2 ka event, suggesting that apron aggradation was driven by changes in climatic regime. Although either increased aridity or a change in precipitation regime could result in increased erosion of terrace scarps, apron aggradation events do not correlate with regional records of aridity. Instead, periods of increased precipitation intensity and/or frequency that occur during climatic transitions most likely drive apron aggradation events.

  10. Influence of lead apron shielding on absorbed doses from cone-beam computed tomography. (United States)

    Rottke, Dennis; Andersson, Jonas; Ejima, Ken-Ichiro; Sawada, Kunihiko; Schulze, Dirk


    The aim of the present work was to investigate absorbed and to calculate effective doses (EDs) in cone-beam computed tomography (CBCT). The study was conducted using examination protocols with and without lead apron shielding. A full-body male RANDO(®) phantom was loaded with 110 GR200A thermoluminescence dosemeter chips at 55 different sites and set up in two different CBCT systems (CS 9500(®), ProMax(®) 3D). Two different protocols were performed: the phantom was set up (1) with and (2) without a lead apron. No statistically significant differences in organ and absorbed doses from regions outside the primary beam could be found when comparing results from exposures with and without lead apron shielding. Consequently, calculating the ED showed no significant differences between the examination protocols with and without lead apron shielding. For the ProMax(®) 3D with shielding, the ED was 149 µSv, and for the examination protocol without shielding 148 µSv (SD = 0.31 µSv). For the CS 9500(®), the ED was 88 and 86 µSv (SD = 0.95 µSv), respectively, with and without lead apron shielding. The results revealed no statistically significant differences in the absorbed doses between examination with and without lead apron shielding, especially in organs outside the primary beam.

  11. Surface characteristics and degradational history of debris aprons in the Tempe Terra/Mareotis fossae region of Mars (United States)

    Chuang, Frank C.; Crown, David A.


    We have documented the surface characteristics and degradational history of a population of 65 lobate debris aprons in the Tempe Terra/Mareotis fossae region of Mars. These aprons were compared to other martian debris aprons to evaluate similarities and differences among different populations, which can provide insight into the dominant controls on apron development. Tempe/Mareotis debris aprons, found at the bases of isolated or clustered massifs, escarpments, and crater interior walls, were studied using Viking Orbiter, Mars Global Surveyor, and Mars Odyssey datasets in a GIS database. Six textures related to degradation of apron surfaces are identified in MOC images, and they are divided into two groups: an upper-surface group and a lower-surface group. Degradation occurs within an inferred smooth, upper surface mantle of ice and debris, producing a sequence of pitted, ridge and valley, and knobby textures of the upper-surface group. Where upper-surface materials have been removed, smooth and ridged textures of the lower-surface group are exposed. Degradation to various depths may expose lower-surface materials, which may consist of the main apron mass, remnants of mantling deposits, or both. A combination of geologic processes may have caused the degradation, including ice sublimation, ice melt, and eolian activity. Apron surfaces have lower maximum thermal inertias and mean surface temperatures than adjacent plains surfaces, which may be explained by the trapping of unconsolidated materials in low-lying pits and valleys formed by surface degradation or from the disruption of crusts on degraded portions of apron surfaces. One feature observed only on Tempe/Mareotis debris aprons are broad ridges, which mimic the shape of massif bases for tens of kilometers. We propose these to be constructional features that could have formed during cycles of increased debris production. Apron morphometric parameters including area, volume, slope, thickness, relief, and H

  12. 'Do lead rubber aprons pose an infection risk?'

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, Helen [Diagnostic Radiographer, Queen Elizabeth Hospital, Kings Lynn NHS Trust (United Kingdom); Strudwick, Ruth M., E-mail: [School of Health, Science and Social Care, University Campus Suffolk, IP4 1QJ (United Kingdom)


    This study was carried out in order to establish whether infection control measures were being undertaken sufficiently on lead rubber aprons within a diagnostic imaging department in the east of England. This study involved the swabbing of a sample of 15 lead rubber aprons used within different areas of the department. Swabs were taken from the area on the underside of the shoulders and from the front of the apron. Each apron was firstly swabbed to determine the current level of microorganism contamination (determination of baseline data) and then again after recommended cleaning with detergent and water (the production of a standard). Comparisons were then made between the number of microorganisms' present (colony forming units/cm{sup 2}) pre and post-cleaning at each location. Additionally, post-cleaning data was compared for each location. All aprons were found to be contaminated with microorganisms, those identified were Coagulase-negative staphylococci, Staphylococcus aureus, Bacillus, Diphtheroids and some fungal spores. No Methicillin resistant strains of Staphylococcus aureus (MRSA) were identified. Recommended cleaning with detergent and water was found to significantly reduce the amount of microorganisms present (the detergent used was Hospec general purpose neutral liquid detergent). Comparisons of the sample sites found that the front of the apron had lower levels of microorganism contamination post-cleaning than the site at the underside of the shoulders. The results suggest that the lead rubber aprons were not being cleaned sufficiently which has infection control implications for the department. In order for cross contamination to be kept to a minimum an effective infection control policy needs to be employed and this should be to carry out regular cleaning with detergent and water which has been shown can significantly reduce contamination.

  13. Efficiency of lead aprons in blocking radiation − how protective are they?

    Directory of Open Access Journals (Sweden)

    Seung-Jae Hyun


    Interpretation: The 0.5 mm lead aprons blocked just over one third of the radiation scattered towards the surgeon. Use of robotic-guidance in a minimally invasive approach provided for a reduction of 62.5% of the overall radiation the surgeon was exposed to during open conventional approach. We conclude that reduced radiation use (e.g. by using robotic guidance is a more effective strategy for minimizing exposure to radiation than reliance on protection by lead aprons, and recommend utilization of practices and technologies that reduce the surgical team’s routine exposure to X-rays.

  14. A model-based approach of scatter dose contributions and efficiency of apron shielding for radiation protection in CT. (United States)

    Weber, N; Monnin, P; Elandoy, C; Ding, S


    Given the contribution of scattered radiations to patient dose in CT, apron shielding is often used for radiation protection. In this study the efficiency of apron was assessed with a model-based approach of the contributions of the four scatter sources in CT, i.e. external scattered radiations from the tube and table, internal scatter from the patient and backscatter from the shielding. For this purpose, CTDI phantoms filled with thermoluminescent dosimeters were scanned without apron, and then with an apron at 0, 2.5 and 5 cm from the primary field. Scatter from the tube was measured separately in air. The scatter contributions were separated and mathematically modelled. The protective efficiency of the apron was low, only 1.5% in scatter dose reduction on average. The apron at 0 cm from the beam lowered the dose by 7.5% at the phantom bottom but increased the dose by 2% at the top (backscatter) and did not affect the centre. When the apron was placed at 2.5 or 5 cm, the results were intermediate to the one obtained with the shielding at 0 cm and without shielding. The apron effectiveness is finally limited to the small fraction of external scattered radiation.

  15. Life cycle of a geyser discharge apron: Evidence from Waikite Geyser, Whakarewarewa geothermal area, North Island, New Zealand (United States)

    Jones, Brian; Renaut, Robin W.; Owen, R. Bernhart


    Waikite, a geyser located in the Whakarewarewa geothermal area on the North Island, New Zealand, has a history of eruptive-dormancy cycles that have been attributed to natural and anthropogenic causes. The last cycle involved an active period from ~ 1932 to 1968/69 that was followed by a period of dormancy that continues today. Such cycles are important because they control the temporal development of the discharge apron. When the geyser is active, growth of the discharge apron is dictated by the precipitation of opal-A, which is controlled by factors such as discharge patterns, water chemistry, pH, temperature, rate of cooling, and the resident microbiota. With dormancy, conditions change radically because water no longer flows down the discharge apron. Instead, the discharge apron lapses into a phase of degradation that, on Waikite, is evident from (1) deflation of the apron surface, (2) blocks splaying off the apron margins along margin-parallel fractures, (3) tension fractures, (4) saucer-shaped collapse zones, (5) increasingly unstable surfaces resulting from subsurface opal-A dissolution, (6) fractures, from which steam and other gases emanate, and (7) incursion of native vegetation around the edge of the apron and on the distal parts of the discharge apron. When the geyser becomes active again, silica precipitation will resume and the discharge apron will once again accrete vertically and expand laterally. Analysis of the Waikite system shows that successions that develop on geyser discharge aprons are formed of unconformity-bounded packages of sinter that reflect the eruptive-dormancy history of the parent geyser.

  16. The Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study : rationale and methods

    NARCIS (Netherlands)

    Kaplan, Bonnie J.; Giesbrecht, Gerald F.; Leung, Brenda M. Y.; Field, Catherine J.; Dewey, Deborah; Bell, Rhonda C.; Manca, Donna P.; O'Beirne, Maeve; Johnston, David W.; Pop, Victor J.; Singhal, Nalini; Gagnon, Lisa; Bernier, Francois P.; Eliasziw, Misha; McCargar, Linda J.; Kooistra, Libbe; Farmer, Anna; Cantell, Marja; Goonewardene, Laki; Casey, Linda M.; Letourneau, Nicole; Martin, Jonathan W.


    The Alberta Pregnancy Outcomes and Nutrition (APrON) study is an ongoing prospective cohort study that recruits pregnant women early in pregnancy and, as of 2012, is following up their infants to 3 years of age. It has currently enrolled approximately 5000 Canadians (2000 pregnant women, their offsp

  17. Answers to if the Lead Aprons are Really Helpful in Nuclear Medicine from the Perspective of Spectroscopy. (United States)

    He, X; Zhao, R; Rong, L; Yao, K; Chen, S; Wei, B


    Wearing lead X-ray-protective aprons is a routine in nuclear medicine department in parts of China. However, the staff are often perplexed by questions such as if it is imperative to wear aprons when injecting radioactive drugs, how much radiation dosage can be shielded and if the apron will produce secondary radiation instead? To answer these questions, a semiconductor detector was employed to record different gamma and X-ray spectra with and without the lead apron or lead sheet. Then, we could estimate the signal shielding ratio to different photons for the lead apron and compare with the hospitals measured data. In general, the two results coincided well. The spectral results showed that the detrimental secondary X-rays irradiation rises when the energy of gamma rays exceeds the K absorption edge of lead (88 keV). Moreover, the aprons are not so effective for gamma rays of 364 keV emitted from (131)I and 511 keV emitted from the positron radioactive nuclides. This work is purely a physical measurement in the laboratory. To the best of our knowledge, this is the first quantitative study on the level of gamma rays protection offered by the medical lead aprons and the importance of the spectroscopic measurements is discussed in this paper.

  18. The leaded apron revisited: does it reduce gonadal radiation dose in dental radiology

    Energy Technology Data Exchange (ETDEWEB)

    Wood, R.E.; Harris, A.M.; van der Merwe, E.J.; Nortje, C.J. (Ontario Cancer Institute, Princess Margaret Hospital, Toronto (Canada))


    A tissue-equivalent anthropomorphic human phantom was used with a lithium fluoride thermoluminescent dosimetry system to evaluate the radiation absorbed dose to the ovarian and testicular region during dental radiologic procedures. Measurements were made with and without personal lead shielding devices consisting of thyroid collar and apron of 0.25 mm lead thickness equivalence. The radiation absorbed dose with or without lead shielding did not differ significantly from control dosimeters in vertex occlusal and periapical views (p greater than 0.05). Personal lead shielding devices did reduce gonadal dose in the case of accidental exposure (p less than 0.05). A leaded apron of 0.25 mm lead thickness equivalent was permeable to radiation in direct exposure testing.

  19. SU-E-I-56: Diagnostic Lead Apron Radiation Exposure Comparison Between Manufacture-Stated and Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Syh, J; Patel, B; Syh, J; Song, X; Freund, D; Ding, X; Wu, H [Willis-Knighton Medical Center, Shreveport, LA (United States)


    Purpose: Several vendors of diagnostic lead apron used routinely in radiology/fluoroscopy claim to manufacture 0.5 mm lead equivalent shielding. The purpose of this investigation was to address the concern of the weight of lead aprons versus the radiation protection they provide. Methods: Seven diagnostic lead aprons were measured and compared for their radiation transmission and attenuation characteristics. The measurements were performed on a Philips Integris. Two settings were used, normal (76 kVp, 14.3 mA) and high (110 kVp, 12.3 mA) to represent typical patient and large patient thickness. Plastic water was placed on the table to represent patient scatter. A Capintec PM-500 ion chamber was placed at approximate chest height where hospital personnel would stand. An uncovered, i.e. lead-unhindered, ion chamber reading was taken to establish the baseline reading of an unprotected personnel. The ion chamber was then wrapped with 0.5mm 99.9% pure Pb material to establish the measurement reading when a diagnostic lead apron attenuates as adequately as 0.5mm Pb. The lead aprons were measured one at a time with the ion chamber fully covered and enclosed within the aprons. Results: On Normal fluoroscopy setting, the 0.5mm pure Pb showed a transmission of 0.4%. No aprons showed a transmission value as low as 0.5mm Pb. The lowest transmission value measured from the aprons was 2.0%, having a 1.5% higher transmission than pure lead. On High fluoroscopy setting, the lowest apron transmission measurement was at 2.8%, which was comparable to the 0.5mm pure Pb which gave a transmission of 3.0%. Conclusion: At Normal fluoroscopy setting, the 0.5mm Pb provided an attenuation that could not be matched by any apron measured. At High fluoroscopy setting, only one apron exhibited comparable transmission values as 0.5mm pure Pb.

  20. Physical analysis of the shielding capacity for a lightweight apron designed for shielding low intensity scattering X-rays


    Seon Chil Kim; Jeong Ryeol Choi; Byeong Kyou Jeon


    The purpose of this paper is to develop a lightweight apron that will be used for shielding low intensity radiation in medical imaging radiography room and to apply it to a custom-made effective shielding. The quality of existing aprons made for protecting our bodies from direct radiation are improved so that they are suitable for scattered X-rays. Textiles that prevent bodies from radiation are made by combining barium sulfate and liquid silicon. These materials have the function of shieldin...

  1. The Alberta Pregnancy Outcomes and Nutrition (APrON) cohort study: rationale and methods. (United States)

    Kaplan, Bonnie J; Giesbrecht, Gerald F; Leung, Brenda M Y; Field, Catherine J; Dewey, Deborah; Bell, Rhonda C; Manca, Donna P; O'Beirne, Maeve; Johnston, David W; Pop, Victor J; Singhal, Nalini; Gagnon, Lisa; Bernier, Francois P; Eliasziw, Misha; McCargar, Linda J; Kooistra, Libbe; Farmer, Anna; Cantell, Marja; Goonewardene, Laki; Casey, Linda M; Letourneau, Nicole; Martin, Jonathan W


    The Alberta Pregnancy Outcomes and Nutrition (APrON) study is an ongoing prospective cohort study that recruits pregnant women early in pregnancy and, as of 2012, is following up their infants to 3 years of age. It has currently enrolled approximately 5000 Canadians (2000 pregnant women, their offspring and many of their partners). The primary aims of the APrON study were to determine the relationships between maternal nutrient intake and status, before, during and after gestation, and (1) maternal mood; (2) birth and obstetric outcomes; and (3) infant neurodevelopment. We have collected comprehensive maternal nutrition, anthropometric, biological and mental health data at multiple points in the pregnancy and the post-partum period, as well as obstetrical, birth, health and neurodevelopmental outcomes of these pregnancies. The study continues to follow the infants through to 36 months of age. The current report describes the study design and methods, and findings of some pilot work. The APrON study is a significant resource with opportunities for collaboration.

  2. Radiation protection of staff in 111In radionuclide therapy--is the lead apron shielding effective? (United States)

    Lyra, M; Charalambatou, P; Sotiropoulos, M; Diamantopoulos, S


    (111)In (Eγ = 171-245 keV, t1/2 = 2.83 d) is used for targeted therapies of endocrine tumours. An average activity of 6.3 GBq is injected into the liver by catheterisation of the hepatic artery. This procedure is time-consuming (4-5 min) and as a result, both the physicians and the technical staff involved are subjected to radiation exposure. In this research, the efficiency of the use of lead apron has been studied as far as the radiation protection of the working staff is concerned. A solution of (111)In in a cylindrical scattering phantom was used as a source. Close to the scattering phantom, an anthropomorphic male Alderson RANDO phantom was positioned. Thermoluminescent dosemeters were located in triplets on the front surface, in the exit and in various depths in the 26th slice of the RANDO phantom. The experiment was repeated by covering the RANDO phantom by a lead apron 0.25 mm Pb equivalent. The unshielded dose rates and the shielded photon dose rates were measured. Calculations of dose rates by Monte Carlo N-particle transport code were compared with this study's measurements. A significant reduction of 65 % on surface dose was observed when using lead apron. A decrease of 30 % in the mean absorbed dose among the different depths of the 26th slice of the RANDO phantom has also been noticed. An accurate correlation of the experimental results with Monte Carlo simulation has been achieved.

  3. A comparison of dose savings of lead and lightweight aprons for shielding of 99m-Technetium radiation. (United States)

    Warren-Forward, Helen; Cardew, Paul; Smith, Bradley; Clack, Llewellyn; McWhirter, Kym; Johnson, Stacey; Wessel, Kimberly


    Nuclear medicine technologists (NMTs) have the highest effective doses of radiation among medical workers. With increase in the use of lightweight materials in diagnostic radiography, the aim was to compare the effectiveness of lead and lightweight aprons in shielding from 99m-Technetium ((99m)Tc) gamma rays. The doses received from a scattering phantom to the entrance, 9cm depth and exit of a phantom were measured with LiF:Mg, Cu, P thermoluminescent dosemeters (TLDs). Doses and spectra were assessed without no shielding, with 0.5-mm lead and lightweight aprons. The lead and lightweight aprons decreased entrance surface doses by 76 and 59%, respectively. The spectral analysis showed that the lightweight apron provided better dose reduction at energies lead was 35% more efficient at higher energies. While lead apron demonstrated better shielding, the additional savings should be considered with the weight differential. It is concluded that the lightweight apron is suitable to be worn by NMTs interacting with patients injected with a (99m)Tc labelled radiopharmaceutical.

  4. The distribution of lobate debris aprons and similar flows on Mars (United States)

    Squyres, S. W.


    Planet-wide mapping of lobate debris aprons and other similar flows on Mars shows a strong concentration in two latitudinal bands roughly 25 deg wide and centered at 40 deg N and 45 deg S. This distribution supports the idea that these flows form when erosional debris is transported downslope and becomes mixed with ice deposited from the atmosphere, as these latitudes should receive high seasonal H2O frost deposition relative to the rest of the planet. Flows are found in the northern hemisphere band wherever old highland surfaces occur but are found in the southern hemisphere only near the two major impact basins, Argyre and Hellas. These areas are apparently characterized by mass wasting that is rapid relative to most of the southern hemisphere highlands. The rate of mass wasting may be related to the degree of consolidation of highland material.

  5. Mud aprons in front of Svalbard surge moraines: Evidence of subglacial deforming layers or proglacial glaciotectonics? (United States)

    Kristensen, Lene; Benn, Douglas I.; Hormes, Anne; Ottesen, Dag


    Large debris-flow units commonly occur on the distal sides of subaqueous end moraines deposited by surges of Svalbard tidewater glaciers, but have rarely been described in terrestrial settings. Some researchers have argued that these kinds of debris flows reflect processes unique to the subaqueous environment, such as the extrusion of subglacial deforming layers or extensive failure of oversteepened moraine fronts. In this paper, we describe terrestrial and subaqueous parts of a single late Holocene moraine system deposited by a major surge of the tidewater glacier Paulabreen in west Spitsbergen. The ice-marginal landforms on land closely resemble the corresponding landforms on the seabed as evidenced by geomorphic mapping and geophysical profiles from both environments. Both onland and offshore, extensive areas of hummocky moraine occur on the proximal side of the maximum glacier position, and large mud aprons (interpreted as debris flows) occur on the distal side. We show that the debris-flow sediments were pushed in front of the advancing glacier as a continuously failing, mobile push moraine. We propose that the mud aprons are end members of a proglacial landforms continuum that has thrust-block moraines as the opposite end member. Two clusters of dates (~ 8000 YBP and ~ 700 YBP) have previously been interpreted to indicate two separate surges responsible for the moraine formation. New dates suggest that the early cluster indicates a local extinction of the abounded species Chlamys islandica. Other changes corresponding to the widespread 8.2 ka event within the fjord, may suggest that the extinction of the C. islandica corresponds to that time.

  6. Physical analysis of the shielding capacity for a lightweight apron designed for shielding low intensity scattering X-rays. (United States)

    Kim, Seon Chil; Choi, Jeong Ryeol; Jeon, Byeong Kyou


    The purpose of this paper is to develop a lightweight apron that will be used for shielding low intensity radiation in medical imaging radiography room and to apply it to a custom-made effective shielding. The quality of existing aprons made for protecting our bodies from direct radiation are improved so that they are suitable for scattered X-rays. Textiles that prevent bodies from radiation are made by combining barium sulfate and liquid silicon. These materials have the function of shielding radiation in a manner like lead. Three kinds of textiles are produced. The thicknesses of each textile are 0.15 mm, 0.21 mm, and 0.29 mm and the corresponding lead equivalents are 0.039 mmPb, 0.095 mmPb, 0.22 mmPb for each. The rate of shielding space scattering rays are 80% from the distance of 0.5 m, 86% from 1.0 m, and 97% from 1.5 m. If we intend to approach with the purpose of shielding scattering X-rays and low intensity radiations, it is possible to reduce the weight of the apron to be 1/5 compared to that of the existing lead aprons whose weight is typically more than 4 kg. We confirm, therefore, that it is possible to produce lightweight aprons that are used for the purpose of shielding low dose radiations.

  7. Physical analysis of the shielding capacity for a lightweight apron designed for shielding low intensity scattering X-rays (United States)

    Kim, Seon Chil; Choi, Jeong Ryeol; Jeon, Byeong Kyou


    The purpose of this paper is to develop a lightweight apron that will be used for shielding low intensity radiation in medical imaging radiography room and to apply it to a custom-made effective shielding. The quality of existing aprons made for protecting our bodies from direct radiation are improved so that they are suitable for scattered X-rays. Textiles that prevent bodies from radiation are made by combining barium sulfate and liquid silicon. These materials have the function of shielding radiation in a manner like lead. Three kinds of textiles are produced. The thicknesses of each textile are 0.15 mm, 0.21 mm, and 0.29 mm and the corresponding lead equivalents are 0.039 mmPb, 0.095 mmPb, 0.22 mmPb for each. The rate of shielding space scattering rays are 80% from the distance of 0.5 m, 86% from 1.0 m, and 97% from 1.5 m. If we intend to approach with the purpose of shielding scattering X-rays and low intensity radiations, it is possible to reduce the weight of the apron to be 1/5 compared to that of the existing lead aprons whose weight is typically more than 4 kg. We confirm, therefore, that it is possible to produce lightweight aprons that are used for the purpose of shielding low dose radiations.

  8. Assessment of the effectiveness of attenuation of leaded aprons through TLD dosimetry and Monte Carlo simulation method

    Energy Technology Data Exchange (ETDEWEB)

    Olaya D, H.; Diaz M, J. A.; Martinez O, S. A. [Universidad Pedagogica y Tecnologica de Colombia, Grupo de Fisica Nuclear Aplicada y Simulacion, 150003 Tunja, Boyaca (Colombia); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)


    Were performed experimental setups using an X-ray equipment continuous emission Pantak DXT-3000 and three types of leaded aprons with thickness of 0.25, 0.5 and 0.75 mm coated with Mylar Fiber coated Mylar on its surface. Apron was located at a distance of 2.5 m with respect focus in order to cover a radiation field size of a meter in diameter. At the beam output were added aluminum filtration in order to reproduce qualities of narrow beams N-40 (E{sub efective} = 33 keV), N-80 (E{sub efective} = 65 keV) and N-100 (E{sub efective} = 83 keV) according to the ISO standard 4037 (1-3). Each lead apron were fixed 10 TLD dosimeters over its surface, 5 dosimeters before and 5 dosimeters after with respect to X-ray beam and were calibrated for Harshaw 4500 thermoluminescent reader system order to assess the attenuation of each apron. Were performed dosimeters readings and were calculated the attenuation coefficients for each effective energy of X-ray quality. In order to confirm the method of effective energy of ISO-4037 and evaluate effectiveness of lead aprons based on energy range for each medical practice was made a Monte Carlo simulation using code GEANT-4, calculating the fluence and absorbed dose in each one of the dosimeters Monte Carlo, then coefficients of linear attenuation were calculated and compared with the experimental data and reported by the National Institute of Standards and Technology (Nist). Finally, results are consistent between theoretical calculation and experimental measures. This work will serve to make assessments for other personalized leaded protections. (Author)

  9. Evidence for Late Pleistocene uplift at the Somma-Vesuvius apron near Pompeii (United States)

    Marturano, Aldo; Aiello, Giuseppe; Barra, Diana


    Detailed stratigraphic and micropalaeontological analyses of samples from boreholes at the Somma-Vesuvius apron, between Pompeii and the sea, allowed reconstruction of Late Quaternary palaeoenvironmental evolution of the Sarno coastal plain. In all, 116 samples were recovered from seven boreholes drilled from 2-10 m a.s.l. to 16.5-26 m b.s.l. Microfossil assemblages, with special regard to benthic foraminifers and ostracods, were used to reconstruct the depositional palaeoenvironment. Fossil remains show that all the pre-79 AD fossiliferous sediments from 2 to - 24 m a.s.l. were deposited in shallow marine waters for a long time despite an appreciable sea level rise. The data indicate alternation of both shallow marine and subaerial conditions during the last ~ 15 kyr, evidencing ground uplift of the area of about 75 m at a rate of ~ 5 mm/year. Marine sediment accumulation (~ 6 m/kyr) and tectonic uplift long offset the sea level rise, and as a consequence, submerged areas remained the same as well.

  10. Organ-specific external dose coefficients and protective apron transmission factors for historical dose reconstruction for medical personnel. (United States)

    Simon, Steven L


    ICRP/ICRU mono-energetic DCCs and the functions integrated over the air-kerma weighted photon fluence of the 12 defined x-ray spectra. The air kerma-weighted DCCs in this work were developed specifically for an irradiation geometry of anterior to posterior (AP) and for the following tissues: thyroid, breast, ovary, lens of eye, lung, colon, testes, heart, skin (anterior side only), red bone marrow (RBM), and brain. In addition, a series of functional relationships to predict DT Ka-1 values for RBM dependent on body mass index [BMI (kg m-2) ≡ weight per height] and average photon energy were derived from a published analysis. Factors to account for attenuation of radiation by protective lead aprons were also developed. Because lead protective aprons often worn by radiology personnel not only reduce the intensity of x-ray exposure but also appreciably harden the transmitted fluence of bremsstrahlung x-rays, DCCs were separately calculated for organs possibly protected by lead aprons by considering three cases: no apron, 0.25 mm Pb apron, and 0.5 mm Pb apron. For estimation of organ doses from conducting procedures with radioisotopes, continuous functions of the reported mono-energetic values were developed, and DCCs were derived by estimation of the function at relevant energies. By considering the temporal changes in primary exposure-related parameters (e.g., energy distribution), the derived DCCs and transmission factors presented here allow for more realistic historical dose reconstructions for medical personnel when monitoring badge readings are the primary data on which estimation of an individual's organ doses are based.

  11. Climate change on Mars and the formation of gullies, lobate debris aprons, and softened craters (United States)

    Parsons, Reid Allen

    Recent data acquired from spacecraft missions has bettered our understanding of the nature and distribution of ice- and water-related features formed during recent periods of climate change on Mars. Numerical modeling of physical processes constrained by these newly acquired observations is an important tool with which hypotheses relating to the Martian climate can be tested. This work describes the development and implementation of a set of these models focused on the formation of a few young, ice- and water-related features. The subjects of this research are gullies, lobate debris aprons (LDAs), and craters with subdued topography known as "softened" craters. Flow of liquid water and ice over and/or within the Martian surface has been invoked in the formation of these features. Quantifying processes such as fluvial erosion and ice deformation using laboratory experiments is a Rosetta stone with which we can read into the climate history of Mars that is written on its surface. We test the hypothesis that sediment transport on gully slopes occurs via fluvial transport processes by developing a numerical sediment transport model based on steep flume experiments performed by Smart [1984]. At 20° slopes, channels 1 m deep by 8m wide and 0.1 m deep by 3 m wide transport a sediment volume equal to the alcove volume of 6 x 105 m3 in 10 hours and 40 days, respectively, under constant flow conditions. Snowpack melting cannot produce the water discharge rates necessary for fluvial sediment transport, unless long-term (kyr) storage of the resulting meltwater occurs. If these volumes of water are discharged as groundwater, the required aquifer thicknesses and aquifer drawdown lengths would be unrealistically large for a single discharge event. More plausibly, the water volume required by the fluvial transport model could be discharged in ˜ 10 episodes for an aquifer 30 m thick, with a recurrence interval similar to that of Martian obliquity cycles (˜0.1 My). Radar

  12. Evaluasi Kekuatan Perkerasan Sisi Udara (Runway,Taxiway,Apron Bandara Juanda Dengan Metode Perbandingan ACN-PCN

    Directory of Open Access Journals (Sweden)

    R. Haryo Triharso Seno


    Full Text Available Fasilitas sisi udara merupakan fasilitas pergerakan pesawat. Fasilitas ini harus memenuhi kekuatan struktur untuk melayani pergerakan pesawat-pesawat yang beroperasi sesuai dengan perencanaan. Tujuan dari penyusunan makalah ini adalah untuk menganalisis apakah perkerasan fasilitas sisi udara di Bandar Udara Juanda saat ini sudah memenuhi batas PCN yang dipersyaratkan atau belum. Analisis dilakukan dengan cara mengevaluasi kekuatan perkerasan runway, taxiway, dan apron eksisting menggunakan metode perbandingan PCN–ACN yang didapat dari pabrik pembuat pesawat, perhitungan dengan software COMFAA dan perhitungan dari Canadian Department of Transportation. Data yang digunakan adalah data pergerakan pesawat termasuk jumlah pergerakan tahunan dan tipe pesawat. Data kekuatan perkerasan sisi udara diperlukan untuk proses analisis. Hasil dari evaluasi menunjukkan B773 memiliki nilai ACN yang melebihi nilai PCN sebesar 50% untuk apron dan 25% untuk runway/taxiway. Besar kelebihan nilai ACN ini tidak mempengaruhi kekuatan struktural karena frekuensi pergerakan yang hanya 45 pergerakan per tahun. Dampak lain adalah pada fungsional perkerasan yang menunjukkan berkurangnya kekesatan runway dari hasil sand patch test.

  13. Interglacial Extension of the Boreal Forest Limit in the Noatak Valley, Northwest Alaska: Evidence from an Exhumed River-Cut Bluff and Debris Apron (United States)

    Edwards, M.E.; Hamilton, T.D.; Elias, S.A.; Bigelow, N.H.; Krumhardt, A.P.


    Numerous exposures of Pleistocene sediments occur in the Noatak basin, which extends for 130 km along the Noatak River in northwestern Alaska. Nk-37, an extensive bluff exposure near the west end of the basin, contains a record of at least three glacial advances separated by interglacial and interstadial deposits. An ancient river-cut bluff and associated debris apron is exposed in profile through the central part of Nk-37. The debris apron contains a rich biotic record and represents part of an interglaciation that is probably assignable to marine-isotope stage 5. Pollen spectra from the lower part of the debris apron closely resemble modern samples taken from the Noatak floodplain in spruce gallery forest, and macrofossils of spruce are also present at this level. Fossil bark beetles and carpenter ants occur higher in the debris apron. Mutual Climatic Range (MCR) estimates from the fossil beetles suggest temperatures similar to or warmer than today. Together, these fossils indicate the presence of an interglacial spruce forest in the western part of the Noatak Basin, which lies about 80 km upstream of the modern limit of spruce forest.

  14. An evaluation of the shielding effectiveness of lead aprons used in clinics for protection against ionising radiation from novel radioisotopes. (United States)

    Deb, Pradip; Jamison, Robert; Mong, Lisa; U, Paul


    The purpose of this study is to evaluate the effectiveness of personal radiation shields currently worn in hospital and other diagnostic environments. This study was performed with four different radioisotopes; (18)F, (99m)Tc, (124)I and (131)I. (18)F results showed a decrease in dose with 0.5-mm Pb shielding but the reduction provided does not warrant its use clinically. (124)I testing demonstrated that dose enhancement can occur in greater shield thicknesses. PET isotope (124)I can be adequately shielded using 0.25-mm Pb equivalent aprons but any higher thickness increase the wearer's dose. As a result more shielding does not always equal more protection. The (131)I test showed that no dose reduction occurred, even when tested with up to 1.25-mm Pb equivalent shielding. Novel radioisotopes being used in the laboratory and clinic should be individually tested as each requires specific shielding testing.

  15. Velocity-porosity relationships for slope apron and accreted sediments in the Nankai Trough Seismogenic Zone Experiment, Integrated Ocean Drilling Program Expedition 315 Site C0001 (United States)

    Hashimoto, Y.; Tobin, H. J.; Knuth, M.


    In this study, we focused on the porosity and compressional wave velocity of marine sediments to examine the physical properties of the slope apron and the accreted sediments. This approach allows us to identify characteristic variations between sediments being deposited onto the active prism and those deposited on the oceanic plate and then carried into the prism during subduction. For this purpose we conducted ultrasonic compressional wave velocity measurements on the obtained core samples with pore pressure control. Site C0001 in the Nankai Trough Seismogenic Zone Experiment transect of the Integrated Ocean Drilling Program is located in the hanging wall of the midslope megasplay thrust fault in the Nankai subduction zone offshore of the Kii peninsula (SW Japan), penetrating an unconformity at ˜200 m depth between slope apron sediments and the underlying accreted sediments. We used samples from Site C0001. Compressional wave velocity from laboratory measurements ranges from ˜1.6 to ˜2.0 km/s at hydrostatic pore pressure conditions estimated from sample depth. The compressional wave velocity-porosity relationship for the slope apron sediments shows a slope almost parallel to the slope for global empirical relationships. In contrast, the velocity-porosity relationship for the accreted sediments shows a slightly steeper slope than that of the slope apron sediments at 0.55 of porosity. This higher slope in the velocity-porosity relationship is found to be characteristic of the accreted sediments. Textural analysis was also conducted to examine the relationship between microstructural texture and acoustic properties. Images from micro-X-ray CT indicated a homogeneous and well-sorted distribution of small pores both in shallow and in deeper sections. Other mechanisms such as lithology, clay fraction, and abnormal fluid pressure were found to be insufficient to explain the higher velocity for accreted sediments. The higher slope in velocity-porosity relationship for

  16. Efficacy of aprons equivalent to 0.5 mm of lead in PET procedures using the Monte Carlo method; Eficacia de aventais equivalentes a 0,5 mm de chumbo em procedimentos PET usando o metodo Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, R.B.; Amaral, A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Campos, L., E-mail: [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil). Dept. de Fisica


    In positron emission tomography (PET), health staff is exposed to 511-keV photons, which is a result of the positron annihilation process. This energy is about four times greater than the 140 keV commonly found in studies based on single photon emission computed tomography (SPECT). Besides this different level of energy, 0.5 mm lead-equivalent aprons have being used either in SPECT or PET procedures. In this context, this work was designed for evaluating the effectiveness of such aprons in individual radioprotection of health professionals involved in positron emission tomography. For this, by using MCNP4C-based Monte Carlo simulations, the average energy delivered per particle to the regions corresponding to operational quantities Hp(10) and Hp(0.07) were calculated for two conditions of individual exposures: wearing and not wearing a 0.05 mm lead-equivalent apron. The results obtained pointed out that Hp(10) has similar value in both situations. On the other hand, for the region corresponding to Hp(0.07), wearing this lead apron will improve this dose in about 26%. On the basis of this work, 0.5 mm lead equivalent aprons do not offer adequate protection for medical staff working on positron emission tomography. (author)

  17. A Comparison and Analog-Based Analysis of Sinuous Channels on the Rift Aprons of Ascraeus Mons and Pavonis Mons Volcanoes, Mars (United States)

    Collins, A.; de Wet, A.; Bleacher, J.; Schierl, Z.; Schwans, B.


    The origin of sinuous channels on the flanks of the Tharsis volcanoes on Mars is debated among planetary scientists. Some argue a volcanic genesis [1] while others have suggested a fluvial basis [2-4]. The majority of the studies thus far have focused on channels on the rift apron of Ascraeus Mons. Here, however, we broadly examine the channels on the rift apron of Pavonis Mons and compare them with those studied channels around Ascraeus. We compare the morphologies of features from both of these volcanoes with similar features of known volcanic origin on the island of Hawai i. We show that the morphologies between these two volcanoes in the Tharsis province are very similar and were likely formed by comparable processes, as previous authors have suggested [5]. We show that, although the morphologies of many of the channels around these volcanoes show some parallels to terrestrial fluvial systems, these morphologies can also be formed by volcanic processes. The context of these features suggests that volcanic processes were the more likely cause of these channels.

  18. Folate, vitamin B12, and vitamin B6 status of a group of high socioeconomic status women in the Alberta Pregnancy Outcomes and Nutrition (APrON) cohort. (United States)

    Fayyaz, Faiqa; Wang, Flora; Jacobs, René L; O'Connor, Deborah L; Bell, Rhonda C; Field, Catherine J


    Folic acid supplementation and food fortification policies have improved folate status in North American women of child bearing age. Recent studies have reported the possible inadequacy of vitamin B12 and B6 in the etiology of neural tube defects in folate-fortified populations. The aims of this study were to describe folate status and its relationship to supplementation and to assess vitamin B12 and B6 status in a cohort of pregnant women. Supplement intake data were collected in each trimester from the first cohort (n = 599) of the Alberta Pregnancy Outcomes and Nutrition (APrON) study. Red blood cell folate (RBCF) and plasma folate, holotranscobalamin, and pyridoxal 5-phosphate were measured. Overt folate deficiency was rare (3%) but 24% of women in their first trimester had suboptimal RBCF concentration (1360 nmol·L(-1)) was observed in approximately half of the women during each pregnancy trimester. Vitamin B12 and B6 deficiencies were rare (pregnancy and over half the women had abnormally high RBCF, suggesting that supplementation during pregnancy is not appropriate in a cohort of women considered to be healthy and a low risk for nutritional deficiencies.

  19. Amazonian Mid-Latitude Regional Glaciation on Mars: Lineated Valley Fill, Lobate Debris Aprons and Plateau Deposits at the Dichotomy Boundary and Implications for Climate Change (United States)

    Head, J. W.; Marchant, D. R.


    The dichotomy boundary on Mars represents a distinct geologic, topographic, morphologic and crustal thickness boundary that is characterized by a wide range of modificational processes. The Deuteronilus-Protonilus region represents the area where the boundary reaches its highest latitude. The fretted terrain, located in the vicinity of the dichotomy boundary at these mid-northern latitudes on Mars, displays two enigmatic terrain types: lobate debris aprons (LDA) and lineated valley fill (LVF). The prevailing hypotheses for their origin has been mass wasting from mesa margins and valley walls, with movement periodically assisted by groundwater seepage or atmospheric vapor diffusion into the debris aprons, causing ice-assisted creep. Creep from opposite valley walls and convergence in valley centers has been called on to explain the parallel, along-valley lineations, and little evidence has been found for down-valley movement. New higher-resolution THEMIS and MOC data, however, show compelling evidence for a more integrated picture of LVF formation, suggesting a significant role for regional glaciation. We find evidence for: 1) localized alcoves, sources of hundreds of narrow, lobate concentric-ridged debris flows; 2) bulbous-headed tributary valley systems, which contain converging LVF that feeds into larger valley systems; 3) rounded-sharp-paired intersections of the corners of tributary entrances into main valleys, with sharp corners pointing down-flow; 4) narrow arete-like linear plateau ridge remnants, commonly parallel to LVF; 5) horseshoe-shaped ridges up-valley of topographic obstacles, with deformed and folded upslope LVF; 6) convergence and merging of LVF in the down-valley directions; 7) deformation, distortion and folding of LVF in the vicinity of convergence; 8) distinctive lobe-shaped termini where LVF emerges into the northern lowlands. We interpret these LVF features to have formed as parts of integrated valley glacial systems extending hundreds of km

  20. Evaluation of the attenuation of the lead aprons with different lead equivalences for use in radiology services; Avaliacao da atenuacao de aventais plumbiferos com diferentes equivalencias de chumbo para uso em servicos de radiologia

    Energy Technology Data Exchange (ETDEWEB)

    Pimentel, Juliana, E-mail: [Hospital Sao Lucas (HSL/PUCRS), Porto Alegre, RS (Brazil); Borgonhi, William Mello, E-mail: [Instituto Pro Universidade Canoense (IPUC), Canoas, RS (Brazil); Vanni, Stefania, E-mail: [Assessoria em Fisica Medica (AFIM), Porto Alegre, RS (Brazil)


    This work has the aim to evaluate the attenuation of personal protective gear of lead rubber with equivalence of 0.25 and 0.50 mmPb, the scattered radiation. It was used as a radiation emitter, a x-ray equipment brand GE® Model XR6000 with maximum voltage of 150 kVp, the maximum electric current of 630 mA. How spreader object was used a cylindrical acrylic simulator with measures 32 cm by 15 cm. To collect the measurements was used the ionizing chambers Fluke Biomedical® Victoreen® model 451B-DE-SI. The individual protective clothing evaluated were two rubber aprons with equivalence of 0.25 and 0.50 mmPb. To perform the experiment the simulator equipment was placed on the table aligned with the primary beam with focus-film distance of one meter. Were used as exposure parameters 85 kVp, 80 mA and 2.5 sec. Recordings were carried out at distances from 50 to 250 cm, ranging from 25 to 25 cm. For each distance were made four measures in the air and four measures with each VPI in front of the meter, checking the equivalent dose rate and tabling the values obtained. For aprons with equivalence 0,25mmPb average attenuation obtained was 94.05%, with standard deviation of 1.36. As for the aprons with 0,50mmPb the affected attenuation was 97.6%, with deviation of 0.75. From the results of this assessment, it is evident the importance of radiological protective clothing in the routines of individuals occupationally exposed to X-ray.

  1. Flow patterns of lobate debris aprons and lineated valley fill north of Ismeniae Fossae, Mars: Evidence for extensive mid-latitude glaciation in the Late Amazonian (United States)

    Baker, David M. H.; Head, James W.; Marchant, David R.


    A variety of Late Amazonian landforms on Mars have been attributed to the dynamics of ice-related processes. Evidence for large-scale, mid-latitude glacial episodes existing within the last 100 million to 1 billion years on Mars has been presented from analyses of lobate debris aprons (LDA) and lineated valley fill (LVF) in the northern and southern mid-latitudes. We test the glacial hypothesis for LDA and LVF along the dichotomy boundary in the northern mid-latitudes by examining the morphological characteristics of LDA and LVF surrounding two large plateaus, proximal massifs, and the dichotomy boundary escarpment north of Ismeniae Fossae (centered at 45.3°N and 39.2°E). Lineations and flow directions within LDA and LVF were mapped using images from the Context (CTX) camera, the Thermal Emission Imaging Spectrometer (THEMIS), and the High Resolution Stereo Camera (HRSC). Flow directions were then compared to topographic contours derived from the Mars Orbiter Laser Altimeter (MOLA) to determine the down-gradient components of LDA and LVF flow. Observations indicate that flow patterns emerge from numerous alcoves within the plateau walls, are integrated over distances of up to tens of kilometers, and have down-gradient flow directions. Smaller lobes confined within alcoves and superposed on the main LDA and LVF represent a later, less extensive glacial phase. Crater size-frequency distributions of LDA and LVF suggest a minimum (youngest) age of 100 Ma. The presence of ring-mold crater morphologies is suggestive that LDA and LVF are formed of near-surface ice-rich bodies. From these observations, we interpret LDA and LVF within our study region to result from formerly active debris-covered glacial flow, consistent with similar observations in the northern mid-latitudes of Mars. Glacial flow was likely initiated from the accumulation and compaction of snow and ice on plateaus and in alcoves within the plateau walls as volatiles were mobilized to the mid

  2. 车床溜板箱防撞装置的改进设计与应用%The design and application of the improvement of the anti-collision device in the lathe apron

    Institute of Scientific and Technical Information of China (English)

    盖立武; 王成; 吴婷婷; 赵亮


    The traditional anti-collision device in the lathe apron can only prevent the apron from vertically colliding onto the chuck or tail stock in some specific situation. The improved device is composed of a set of guide rods and five processing button located differently. The innovated device can not only have the previous function, but also keep the small feeding carriage or blade carrier motor from bumping onto the tail stock vertically and horizontally. So the new anti-collision device can be in functionality of protection, regardless of the any position of the tail stock in the guide way. And the real applications demonstrate ; compared with the traditional one, the initiated device expands the scale of security protection and shortens the time of regulation.%针对传统的车床溜板箱防撞装置只能防止溜板箱在某一特定情况下沿纵向与卡盘或尾座的碰撞,设计了一套由导向杆和5个位于溜板箱上不同位置的行程开关所组成的防撞装置.此防撞装置既可以防止溜板箱在纵向与卡盘或尾座的碰撞,又可防止小滑板(或刀架电动机)在纵向和横向上与尾座的碰撞,因此尾座不论在导轨的任何位置上,此防撞装置均能起到保护作用.实际运用显示:改进后的车床溜板箱防撞装置与以前的防撞装置相比较,安全防护范围扩大了,调整时间缩短了.

  3. Experimental study on mechanism of energy dissipation and erosion control of aprons for sluices%闸下海漫柔性加糙体消能防冲机理试验

    Institute of Scientific and Technical Information of China (English)

    史国庆; 文恒; 牟献友


    Based on the laboratory hydraulic model tests, the distribution of three-dimensional velocity after raising the roughness of the aprons by means of scrap tires was measured. The results show that the bottom velocity of water obviously decreases and the average velocity of the whole cross-section is approximately equal. With the increase of the tires, the average turbulence intensity and the additional shear stress and the fluid mixing increase so as to improve the efficiency of energy dissipation.%通过室内水工模型试验,量测了采用废旧轮胎加糙后三维流速的分布.结果表明:加糙后近底流速明显降低,但整个断面的平均流速近似相等;随着轮胎排数的增加,水流紊流强度平均值增大,附加切应力增大,流体质点间相互混掺的情况加剧,从而使消能效率得以提高.


    Directory of Open Access Journals (Sweden)

    Zbigniew Matuszak


    Full Text Available This work presents the general characteristics of the port system. It defines sets and functions describing the structure and work of the port. Moreover, it characterizes foundations of the massive handling theory. It provides basic literature information about selected processes and models of the massive handling theory. On the example of a transportation company serving the loading on ships in the port of Szczecin, it shows the loading method. The material loading onto ships was the sodium water glass. There are observation results of operation times comprising the data available to determine parameters of the massive handling theory. Operations covered in the analysis include: the arrival of the ship at the port’s road, waiting for enter the port, passing through the fairway, waiting for loading, loading, determination of the cargo’s weight, preparation of documents and waiting for leaving the port. It presents critical remarks about possibilities of using the data obtained to describe loading cargo on a ship with the use of elements of the massive handling theory.

  5. A Support System to Tie Apron Strings to Debris Flow

    Institute of Scientific and Technical Information of China (English)


    @@ Scientists from the Chengdubased CAS Institute of Mountain Hazards and Environment (IMHE) recently worked out a decision-making support system for disaster mitigation on debris fans in mountainous regions.As a domestic vanguard, the system plays a key role in the fight against debris flow and helping to reduce casualties.

  6. Damage of Concrete Parking Aprons From Auxiliary Power Unit (APU) exhaust and Spilled Jet Oils (United States)


    attacking the sulphoaluminates as well. Finally, the Portland cement binder may have to be replaced by a neutral material (pH of 7) such as polymer concrete... sulphoaluminates (8) as well. Finally, the Portland cement binder may have to be replaced by a neutral material (pH of 7) such as polymer concrete or

  7. Iron-Manganese Redox Reactions in Endeavour Crater Rim Apron Rocks (United States)

    Ming, D. W.; Mittlefehldt, D. W.; Gellert, R.; Peretyazhko, T.; Clark, B. C.; Morris, R. V.; Yen, A. S.; Arvidson, R. E.; Crumpler, L. S.; Farrand, W. H.; Grant, J. A., III; Jolliff, B. L.; Parker, T. J.; Schroder, C.


    The Mars Exploration Rover Opportunity has been exploring Noachian age rocks and outcrops on the rim of the 22 km diameter Endeavour crater since August 2011. The Cape York area is a low-lying rim of Endeavour that contains 3 distinct lithologies: 1) the stratigraphically lowest Matijevic fm of pre-impact lithology, 2) Shoemaker fm of impact breccias, and 3) the stratigraphically highest rim lithology Grasberg fm of post-impact sediments that drape the lower slopes of the rim. The sulfate-rich sediment of the Burns fm lies unconformably over the Grasberg fm. Ca-sulfate veins were discovered in Grasberg fm sediments; the sulfates precipitated from aqueous fluids flowing upward through these materials. Opportunity investigated the chemistry and morphology of outcrops in the Matijevic fm that have Fe(sup 3+)-rich smectite detected by orbital signatures returned by CRISM on MRO. Matijevic fm also contains "boxwork" fractures with chemistry consistent with an Al-rich smectite and veins that appear to be rich in Ca-sulfate. More recently on Cape Tribulation, Opportunity has characterized two S-, Mg- and Mn-rich rich rocks overturned and fractured by the rover's wheels on Cook Haven. Those rocks have been dubbed "Pinnacle Island" and "Stuart Island" and will be referred to as the "Island" rocks. The objectives of this study are to characterize the Fe and Mn contents in the Cape York materials, including the two Island rocks, and to provide a model for Mn mobilization and precipitation. Detailed geochemistry of Endeavour rim rocks is presented in a companion paper. Geochemical trends and elemental associations were obtained from data returned by the Alpha Particle X-ray Spectrometer (APXS) on Opportunity.

  8. A study of the behaviour of and the forces in a bed protecting mattress: the falling apron

    NARCIS (Netherlands)

    Vrijling, J.K.; Ravenstijn, P.


    In many cases the bottom around a structure that is exposed to current has to be protected by a mattress. The purpose of the mattress is to protect the soil besides the structure from erosion and scour, thus preserving the strength of the foundation of the structure. Examples are the bottom protecti

  9. Fuzzy Decision Optimization of Top Pin and Apron for Roving Frame%粗纱机上销和胶圈的模糊决策选优

    Institute of Scientific and Technical Information of China (English)

    崔红; 高秀丽; 高大伟; 吕立斌



  10. Samtaler i hvid kittel: En analyse af indlaeggelsessamtaler og deres institutionelle betingelser (Conversations in White Aprons: An Analysis of Hospitalization Conversations and Their Institutional Conditions). ROLIG Papir 47. (United States)

    Becker, Jytte

    This report focuses on the communication that takes place between nurses and patients in a hospital setting. Nurses have for years been accused of talking at patients rather than talking to them. They have also been accused of using a language that patients do not know. The problem is partly a result of individual roles within the medical…

  11. Installation Restoration Program (IRP). Aircraft Parking Apron Area. Volume 1. 152nd Reconnaissance Group, Nevada Air National Guard, Reno-Cannon International Airport, Reno, Nevada (United States)


    addition of oxygen, nutrients, or the introduction of different strains of microorganisms are required to obtain optimum I bioremediation at the Site. I Groundwater Samples, IRP Site No. 12 152nd RG, Nevada Air National Guard, Reno, Nevada Well IUD Sam0*1ID Number Round (ji MW2 MW2-(1) Round 1...addition of microorganisms is required to obtain optimum bioremediation at the site. 6.2.1 Soil Vapor Survey The soil vapor survey consisted of a

  12. Capricious, or tied to history’s apron strings? Floristic regions in north-west European brambles (Rubus subgenus Rubus, Rosaceae)

    NARCIS (Netherlands)

    Haveman, R.; Bijlsma, R.J.; Ronde, de I.; Schaminee, J.H.J.


    Aim To classify and describe distributional patterns in apomictic Rubus subgenus
    Rubus in north-west Europe and to characterize the major regions by
    statistically derived character species.
    Location North-western Europe, in particular Ireland, the United Kingdom,
    the Netherlands, Den

  13. 78 FR 57211 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals (United States)


    ... rehabilitation. Runway 17/35 rehabilitation design. Taxiway/apron/fuel road pavement replacement. Taxiway/apron/fuel road pavement replacement construction. Boarding gate area renovation preliminary design. Boarding... improvements (design and construction). Drainage ditch improvements (design and construction). Apron...

  14. Analysis and Treatment of Soleplate Weakness in the Water Apron of Surface Drainage Opening of Ankang Hydropower Station%安康水电站表孔消力池底板缺陷分析及其处理

    Institute of Scientific and Technical Information of China (English)

    李幼木; 王宏斌



  15. 77 FR 49852 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals (United States)


    .../29 pavement rehabilitation. Taxiway B pavement rehabilitation. Runway 15/33 pavement rehabilitation... commercial apron. General aviation apron pavement rehabilitation. Decision Date: July 12, 2012. FOR FURTHER... equipment--front end loader. Wildlife hazard assessment. Rehabilitate taxiway G, design and...

  16. 46 CFR Sec. 3 - Terminal operating contract. (United States)


    ... Facilities as used in this agreement means piers, wharves, warehouses, covered and/or open storage space... functional field, e.g., handling lines; directing tug operations for docking vessels; planning and conducting..., and agrees to furnish its best skill and judgment in planning, supervising and performing the work,...

  17. Human Factors Assessment: M9 Armored Combat Earthmover (ACE) (United States)


    65 29. A mechanic assisting the operator in inserting the apron safety pin ...... .66 30. Damage to the floodlight guard...dozer blade lock pin next to the point of the ball point pin. " 65 S.% - % " Figure 29 shows a mechanic inserting the apron safety pin while the perform all tasks alone. Figure 29. A mechanic assisting the operator in inserting the apron safety pin . 0%’ 66 e% % ---------- Implications for

  18. Reduction of uterus dose in clinical thoracic computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Danova, D.; Keil, B.; Kaestner, B.; Klose, K.J.; Heverhagen, J.T. [Marburg Univ. (Germany). Dept. of Diagnostic Radiology; Wulff, J.; Fiebich, M.; Zink, K. [Univ. of Applied Sciences Giessen-Friedberg (Germany). Inst. of Medical Physics and Radiation Protection


    Purpose: The aim of this study was to investigate the potential dose reduction in the uterus as a result of lead apron protection during thoracic CT scans. Moreover, the distribution of the radiation dose in the uterus was determined in order to obtain information about the ratio of internally and externally scattered radiation. Materials and Methods: The uterus doses during thoracic CT were determined by measuring organ doses using an Alderson-RANDO {sup registered} -Phantom and thermoluminescent dosimeters. A 0.25 mm lead equivalent protective apron was used to shield the abdominal area. Three measurement conditions were evaluated: without lead apron, covered with lead apron and wrapped with lead apron. The uterus dose with and without shielding describes the mean value and standard deviation of all examinations and all measurement points in the organ. Results: The uterus dose by thoracic CT was measured to be approximately 66.5 {+-} 3.1 {mu}Gy. If the abdomen is covered with a 0.25 mm Pb equivalent lead apron in the front area and on both sides, the uterus dose is reduced to 49.4 {+-} 2.8 {mu}Gy (26 % reduction, p < 0.001). If a lead apron is wrapped around the abdomen, providing 0.50 mm Pb shielding in the anterior section due to overlap, and 0.25 mm Pb in the posterior section and on both sides, the uterus dose is reduced even more to 43.8 {+-} 2.5 {mu}Gy (34 % reduction, p < 0.001). The dose distribution when the lead apron covers the abdomen shows that the shielding is effective for the scatter radiation that comes from the anterior part. Moreover, the wrapped apron protects the uterus from all directions and is even more effective for dose reduction than the covering apron. Conclusion: Our findings demonstrate that protective aprons are an effective dose reduction technique without additional costs and little effect on patient examination time. (orig.)

  19. Calculation of Contact Angle and Optimization About Group Driving of Apron Belt of Double Twist Frames Base on Calculation Models%基于模型的倍捻机龙带集体传动包角计算与优化

    Institute of Scientific and Technical Information of China (English)

    孙文云; 竺志超; 徐海平; 颜世强



  20. Commencement Bay Studies Phase II, Environmental Impacts Assessment. (United States)


    oriented uses (marinas, parks, wharves, public facilities and open space restaurants, specialty food markets , etc.) and on-land residential uses on the...alteration of natural habitat and water courses used by sportsfishermen, boaters, beachcombers, birdwatchers , and others engaged in recreational pursuits...development of marinas in areas with natural amenities may degrade the use of the site and adjacent areas for other recreational pursuits such as birdwatching

  1. Coastal structural remains on the east coast of India: Evidence of maritime activities and their significance

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    , Masulipatnam and Nagapattanam. On the other hand, Dronimukha refers to a port situated near the confluence of the river and the sea. Dronimukha was also a market place. Interestingly, the ports such as Dwarka, Tondi and Puhar also had the same meaning... and these port towns had well-established markets and hinterland connections (Roy 1994). Besides the geographical considerations in the location of ports, the maritime structures such as boatbuilding yards, landing places, boat shelters, causeways, wharves...

  2. 78 FR 69302 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List... (United States)


    ... aircraft parking apron to the east, and East Marine Way to the south. The site consisted of three units: Unit 1 was an area along the edge of a concrete parking apron where aircraft drop tanks were formerly... underground pipeline (Norwalk-El Toro Pipeline) was believed to exist within this area. However, based on...

  3. A mineral seed coating for control of seedling diseases of alfalfa suitable for organic production systems (United States)

    Most alfalfa seed is treated with the systemic fungicide mefenoxam (Apron XL) for control of soilborne seedling diseases. However, Apron XL does not have activity against Aphanomyces euteiches, the causal agent of Aphanomyces root rot (ARR), which is an important component of the alfalfa root rot co...

  4. Bonneville Project: CFD of the Spillway Tailrace

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.; Romero Gomez, Pedro DJ


    US Army Corps of Engineers, Portland District (CENWP) operates the Bonneville Lock and Dam Project on the Columbia River. High spill flows that occurred during 2011 moved a large volume of rock from downstream of the spillway apron to the stilling basin and apron. Although 400 cubic yards of rocks were removed from the stilling basin, there are still large volumes of rock downstream of the apron that could, under certain flow conditions, move upstream into the stilling basin. CENWP is investigating operational changes that could be implemented to minimize future movement of rock into the stilling basin. A key analysis tool to develop these operational changes is a computational fluid dynamics (CFD) model of the spillway. A free-surface CFD model of the Bonneville spillway tailrace was developed and applied for four flow scenarios. These scenarios looked at the impact of flow volume and flow distribution on tailrace hydraulics. The simulation results showed that areas of upstream flow existed near the river bed downstream of the apron, on the apron, and within the stilling basin for all flows. For spill flows of 300 kcfs, the cross-stream and downstream extent of the recirculation zones along Cascade and Bradford Island was very dependent on the spill pattern. The center-loaded pattern had much larger recirculation zones than the flat or bi-modal pattern. The lower flow (200 kcfs) with a flat pattern had a very large recirculation zone that extended half way across the channel near the river bed. A single flow scenario (300 kcfs of flow in a relatively flat spill pattern) was further interrogated using Lagrangian particle tracking. The tracked particles (with size and mass) showed the upstream movement of sediments onto the concrete apron and against the vertical wall between the apron and the stilling basin from seed locations downstream of the apron and on the apron.

  5. 身影(英文)

    Institute of Scientific and Technical Information of China (English)


    Zhang Jing: Putting on a Cerise Apron to Make Noodles张静:系着水红色围裙的面馆老板If you roamed around the streets in the eastern suburbs of Xi'an, the capital city of Northwest China's Shaanxi Province, you'd see a small, but thriving, noodle restaurant and a smiling young woman with a cerise apron standing at the gate to greet each customer during peak hours. Her happy and confident smile and her cerise apron certainly make her

  6. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... be required to wear a lead apron to prevent radiation exposure. The radiation dose directly outside of ... child will stay in the department for a recovery period and will be given instructions on any ...

  7. 76 FR 14064 - Notice of Inventory Completion: U.S. Department of the Interior, Bureau of Indian Affairs... (United States)


    ...-grass bundle, 2 sandals, 1 wood spindle, 2 cotton spindle sticks, 27 textile fragments, 1 torch, 1 yucca fiber apron, 1 yucca fiber quid, and 1 lot of yucca fiber yarn. In 1979, human remains representing...

  8. Ice and debris in the fretted terrain, Mars (United States)

    Lucchitta, B. K.


    Viking moderate and high resolution images along the northern highland margin have been monoscopically and stereoscopically examined in order to study the development of fretted terrain. Young debris aprons around mesas and debris in tributary channels create typical fretted morphologies identical to ancient fretted morphologies. This suggests that the debris-apron process operating relatively recently also shaped the fretted terrain of the past. The debris aprons were lubricated by interstitial ice derived from ground ice. Abundant collapse features suggest that ground ice existed and may have flowed in places. The fretting process has been active for a long period and may be active today. The location of debris aprons in two latitudinal belts may be controlled by atmospheric conditions that permit ice in the region to remain in the ground below depths of about one meter and temperatures warm enough for ice to flow.

  9. Basement and climate controls on proximal depositional systems in continental settings

    NARCIS (Netherlands)

    Ventra, D.


    This doctoral dissertation discusses the sedimentology and dynamics of selected, modern and ancient clastic depositional systems (alluvial fans and colluvial aprons) at continental basin margins. The focus on single depositional systems gave the opportunity to devote particular attention to sediment

  10. Utilizing electromagnetic shielding textiles in wireless body area networks. (United States)

    Sung, Grace H H; Aoyagi, Takahiro; Hernandez, Marco; Hamaguchi, Kiyoshi; Kohno, Ryuji


    For privacy and radio propagation controls, electromagnetic shielding textile could be adopted in WBANs. The effect of including a commercially available electromagnetic shielding apron in WBANs was examined in this paper. By having both the coordinator and the sensor covered by the shielding apron, signal could be confined around the body; however signal strength can be greatly influenced by body movements. Placing the shielding apron underneath both antennas, the transmission coefficient could be on average enhanced by at least 10dB, with less variation comparing to the case when apron does not exist. Shielding textiles could be utilized in designing a smart suit to enhance WBANs performance, and to prevent signals travelling beyond its intended area.

  11. Late Amazonian Glaciations in Utopia Planitia, Mars (United States)

    Osinski, G. R.; Capitan, R. D.; Kerrigan, M.; Barry, N.; Blain, S.


    We present evidence from western Utopia Planitia, including lineated valley fill and lobate debris aprons, for widespread glaciations over a large expanse of the northern plains and dichotomy boundary during Late Amazonian times.

  12. 78 FR 71566 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to a... (United States)


    ... steel sheet pile cell structure with a concrete apron, partial concrete encasement of the piling and an... projects. However, these data are largely for impact driving of steel pipe piles and concrete piles as...

  13. 46 CFR 153.933 - Chemical protective clothing. (United States)


    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Operations General Vessel Safety... or shoe covers. (4) Coveralls or lab aprons. Note: “Guidelines for the Selection of...

  14. 滑坡涌浪对高桩码头船舶撞击力的影响%Effects of landslide generated impulse waves on ship impact force for pile wharf

    Institute of Scientific and Technical Information of China (English)

    王平义; 韩林峰; 喻涛; 孟彩霞


    涌浪作为库岸滑坡的主要次生灾害,给库区码头、船舶以及水工建筑物带来巨大的安全隐患。高桩码头是目前三峡库区最为常见的码头结构形式之一,船舶撞击力对其在使用阶段的稳定性、安全性具有至关重要的影响。通过水槽模型试验,对滑坡涌浪作用下三峡库区系泊船舶与高桩码头间的撞击力进行研究。试验结果表明:系泊船舶对高桩码头的最大撞击力与涌浪初始波高、水体附加质量等参数有关,与水深无关;而用《港口工程荷载规范》计算得到的船舶撞击力与试验值相比偏小,不利于库区码头的设计安全。结合相关试验数据,提出滑坡涌浪影响下高桩码头船舶撞击力计算公式。%As the main secondary result of reservoir bank landslides, surges pose enormous potential risk to wharves, ships, and hydraulic structures in the Three Gorges Reservoir ( TGR) area. The high⁃pile wharf is cur⁃rently one of the most common wharf structures in TGR. Ship impact has a significant effect on the stability and safety of working wharves. Using flume model experiments, the landslide surge impact force between ships and wharves in the TGR was studied. The results show that the maximum impact force correlates to the height of the leading wave and the added water mass coefficient, but is not correlated to the water depth. The ship impact forces computed by the "Lode Code for Harbor Engineering" are smaller than the experimental values and therefore are unsuitable for safe wharf design. Combined with relevant experimental data, this paper proposes an equation for landslide surge impact force between ships and high⁃pile wharves.

  15. Heat stress evaluation of two-layer chemical demilitarization ensembles with a full face negative pressure respirator. (United States)

    Fletcher, Oclla Michele; Guerrina, Ryan; Ashley, Candi D; Bernard, Thomas E


    The purpose of this study was to examine the heat stress effects of three protective clothing ensembles: (1) protective apron over cloth coveralls including full face negative pressure respirator (APRON); (2) the apron over cloth coveralls with respirator plus protective pants (APRON+PANTS); and (3) protective coveralls over cloth coveralls with respirator (PROTECTIVE COVERALLS). In addition, there was a no-respirator ensemble (PROTECTIVE COVERALLS-noR), and WORK CLOTHES as a reference ensemble. Four acclimatized male participants completed a full set of five trials, and two of the participants repeated the full set. The progressive heat stress protocol was used to find the critical WBGT (WBGTcrit) and apparent total evaporative resistance (Re,T,a) at the upper limit of thermal equilibrium. The results (WBGTcrit [°C-WBGT] and Re,T,a [kPa m(2) W(-1)]) were WORK CLOTHES (35.5, 0.0115), APRON (31.6, 0.0179), APRON+PANTS (27.7, 0.0244), PROTECTIVE COVERALLS (25.9, 0.0290), and PROTECTIVE COVERALLS-noR (26.2, 0.0296). There were significant differences among the ensembles. Supporting previous studies, there was little evidence to suggest that the respirator contributed to heat stress.

  16. Study on Structure of Arched Longitudinal Beams of Deep Water Wharf

    Institute of Scientific and Technical Information of China (English)


    High-pile and beam-slab quays have been widely used after several years development. They are mature enough to be one of the most important structural types of wharves in China coastal areas. In order to accommodate large tonnage vessels, wharves should be constructed in deep water gradually. However, conventional high-pile and beam-slab structures are hard to meet the requirements of large deep-water wharf. According to arch's stress characteristics, a new type of wharf with catenary arched longitudinal beams is presented in this paper. The new wharf structure can make full use of arch's overhead crossing and reinforced concrete compression resistance, improve the interval between transverse bents greatly, and decrease underwater construction quantity. Thus, the construction cost cab be reduced. Take the third phase project of the Yangshan Deep-water Port for example, comparative analysis on catenary arched longitudinal beams and conventional longitudinal beams has been made. The result shows that with the same wharf length and width, the same loads and same longitudinal beam moment, catenary arch structure can improve the interval between bents up to 28 m, decrease the number of piles and underwater construction quantity.

  17. Estimation of staff lens doses during interventional procedures. Comparing cardiology, neuroradiology and interventional radiology. (United States)

    Vano, E; Sanchez, R M; Fernandez, J M


    The purpose of this article is to estimate lens doses using over apron active personal dosemeters in interventional catheterisation laboratories (cardiology IC, neuroradiology IN and radiology IR) and to investigate correlations between occupational lens doses and patient doses. Active electronic personal dosemeters placed over the lead apron were used on a sample of 204 IC procedures, 274 IN and 220 IR (all performed at the same university hospital). Patient dose values (kerma area product) were also recorded to evaluate correlations with occupational doses. Operators used the ceiling-suspended screen in most cases. The median and third quartile values of equivalent dose Hp(10) per procedure measured over the apron for IC, IN and IR resulted, respectively, in 21/67, 19/44 and 24/54 µSv. Patient dose values (median/third quartile) were 75/128, 83/176 and 61/159 Gy cm(2), respectively. The median ratios for dosemeters worn over the apron by operators (protected by the ceiling-suspended screen) and patient doses were 0.36; 0.21 and 0.46 µSv Gy(-1) cm(-2), respectively. With the conservative approach used (lens doses estimated from the over apron chest dosemeter) we came to the conclusion that more than 800 procedures y(-1) and per operator were necessary to reach the new lens dose limit for the three interventional specialties.


    Institute of Scientific and Technical Information of China (English)

    Arindam SARKAR; Subhasish DEY


    The safety of an apron of the energy dissipator is threatened by the large-scale scour in the downstream of the apron due to the erosive action of a horizontal jet issuing from a sluice opening. Also, large-scale deposition of the scoured sediments due to an impinging jet in a plunging pool type energy dissipator affects the passage of flow adversely in the downstream channels. Owing to the significant practical importance, the problem of local scour due to jets has been studied by many investigators. In this paper, a comprehensive review of the up-to-date investigations on local scour due to horizontal and impinging jets is presented including all possible aspects, such as scouring process, parameters affecting scour, time variation of scour,velocity distribution on the apron and within the scour hole, development of boundary layer thickness, bed shear stress, scour estimation formulas and protection works.

  19. A methodology to split the total cumulative Hp(10) dose into the Hp(10) i doses received during various procedures performed by interventional cardiologist. (United States)

    Domienik, Joanna


    The methodology describing how to split the cumulative Hp(10) dose of interventional cardiologists into Hp(10) i doses received during procedures of various types based on procedure-specific ELDO coefficients and Hp(3) doses per procedure is presented. The appropriate equations for Hp(10) i (Hp(10) for procedure type i), depending on the number of various procedure types (i  =  1 … 4) performed by a particular physician, are derived. The methodology can be applied to whole-body doses measured on the lead apron and therefore can be used for optimisation of work practices in those catheterisation labs where routine dosimeter is worn above the apron.

  20. Identification of irradiated crab using EPR

    Energy Technology Data Exchange (ETDEWEB)

    Maghraby, A. [Radiation Dosimetry Department, National Institute for Standards (NIS), Ministry of Scientific Research, Haram, 12211- Giza, P.O. Box: 136 (Egypt)]. E-mail:


    EPR spectroscopy is a fast and powerful technique for the identification of irradiated food. Crab exoskeleton was divided into six parts: dactyl, cheliped, carapace, apron, swimming legs, and walking legs. Samples of the exoskeleton were prepared and irradiated to Cs-137 gamma radiation in the range (1.156-5.365 kGy). EPR spectra of unirradiated as well as irradiated samples were recorded and analyzed. Response to gamma radiation was plotted for each part of the exoskeleton, dactyl was found to be the most sensitive part, followed by the apron (38%), cheliped (37%), walking legs (30%), swimming legs (24%), and carapace (21%) relative to the dactyl response.

  1. Utjecaj uvjeta tretmana sjemena na kemijski sastav zrna suncokreta


    Šimić, Branimir; Popović, Ruža; Andrić, Luka; Plavšić, Hrvoje; Ivanišić, Ilonka; Čupić, Tihomir; Jurković, Zorica


    Istraživanjem je utvrđen utjecaj tretmana sjemena na kemijski sastav zrna suncokreta (Fakir i Apolon) tijekom skladištenja od 12 mjeseci. Naturalni i tretirani uzorci sjemena suncokreta s insekticidima Apron + Chinok, te Apron + Geocid, upakirani su u papirnatu dvoslojnu natron vreću i uskladišteni u betonsko-montažno skladište (vlaga zraka 60-75% i temperatura 20-25oC). Nakon 12 mjeseci sadržaj ulja u zrnu izmjeren je spektroskopskom metodom nuklearne magnetne rezonancije (NMR). Rezultati...

  2. Utjecaj tretmana sjemena na sadržaj ulja u zrnu


    Šimić, Branimir; Krizmanić, Miroslav; Liović, Ivica; Miljić, Anto; Bilandžić, Marijan; Popović, Ruža


    Zrno suncokreta specifičnih je svojstava s obzirom na genotip, proces dorade sjemena, tretman i skladištenje a uslijed toga često dolazi do promjene kemijskog sastava zrna. Ovim istraživanjem utvrđena je promjena kemijskog sastava zrna (sadžaj ulja, %/ST) opadanje energije klijanja i klijavosti sjemena suncokreta, a ispitivanje je obavljeno na netretiranom (kontrola) i tretiranom sjemenu (T1 : Apron 35 DS + Geocid ST-35 i T2 : Apron 35 DS + Chinok 600FS). Analizirano je sjeme dva hibrida sunc...

  3. Positioning of personnel dosimeters - comments on replies

    Energy Technology Data Exchange (ETDEWEB)

    Field, R.W. (Academy of Health Sciences, U.S. Army, Fort Sam Houston, TX); Wiatrowski, W.A. (Audi L. Murphy Memorial Veterans Hospital, San Antonio, TX (USA)); Bushong, S.C. (Baylor Univ., Houston, TX (USA). Coll. of Medicine)


    Comments are made on a paper published in 1980 concerning the positioning of personnel dosimeters on individuals wearing protective aprons in diagnostic radiology. The main issue under discussion is whether an additional film badge should be worn on the collar to monitor head and neck exposure while wearing the lead apron over the whole body badge to avoid misinterpretations of reported 'whole body' exposure data. The recommendations on this issue are conflicting in NRCP Reports 57 and 59 and thus clarification is sought.

  4. Organochlorinated pesticides in the Argentine Antarctic sector and Atlantic coastline waters. (United States)

    García Fernández, J C; Casabella, A N; Marzi, A A; Astolfi, E; Roses, O; Donnewald, H; Villamil, E


    The presence of organochlorinated pesticides in water samples drawn in the Argentine Antarctic Sector and Atlantic coastline has been proved. In general, these samples showed quantities that varied between a few hundredths of a ppmm to slightly more than 1 ppmm, although in some cases and for certain pesticides, depending on the locations, the levels found were definitely higher. With the exception of Dieldrin, which appeared in only one sample/in what would seem to be its course few hundredths of a ppm, to slightly more than 1 ppmm, although in some cases and for certain pesticides found were the same as those reported in previous investigations. The isolated cases of high pesticide contents in water samples drawn at wharves and of snow in the vicinity of Almirante Brown Base show up clearly the influence of human activity on the contamination of the environment.

  5. Tier-mounted level luffing crane for container handling; Container handling yo tire mount shiki suihei hikikomi kuren

    Energy Technology Data Exchange (ETDEWEB)



    This level luffing crane was delivered to Iwakuni Port Control Office of Yamaguchi prefecture for container handling. Main specifications: (1) Rated load: 39t for a hook, 30.5t for a spreader, (2) Outrigger layout: 12m in a normal direction, 15m in a traveling direction, (3) Maximum radius: 35m, (4) Minimum radius: 11.5m, (5) Lift: 40m. Features: (1) Possible of loading/unloading works for 20,000DWT class container ships, (2) Possible of loading/unloading works for 32,000DWT class cargo ships, (3) Tier-mounted traveling unit, steering unit with an average swing radius of 35m, and possible position or wharf change work on wharves, (4) Possible of movement between parallel berths apart from each other by 300m by engine power generation. (translated by NEDO)


    Institute of Scientific and Technical Information of China (English)

    LIU Shi-he; DUAN Hong-dong; LU Jing


    Wall pressure fluctuation is one of the source terms which result in the vibration of hydraulic structures. To consider both the space and time correlation of the pressure field, the method of proper orthogonal decomposition and low-dimensional approximation were used here to describe the pressure signals of the turbulent boundary layer, the apron of the stilling pond and the vertically impinging jet.

  7. What Is Meant by the Term "Group" Mentoring? (United States)

    Kroll, Jonathan


    Much like traditional dyadic mentoring experiences, group mentorship has been practiced since time immemorial. Benjamin Franklin, for example, as a young entrepreneur created the Leather Apron Club, a group mentoring experience for a select group of Philadelphia tradesmen. Since the late 1990s, when group mentoring became a serious focus of…

  8. 40 CFR 170.240 - Personal protective equipment. (United States)


    ... shirts, long pants, short pants, shoes, socks, and other items of work clothing are not considered... outside the chemical-resistant gloves under which they are worn. Chemical-resistant gloves with non... long-sleeved shirt, long pants, shoes, socks, chemical-resistant apron, and any protective...

  9. Characterization of Textiles Used in Chefs' Uniforms for Protection Against Thermal Hazards Encountered in the Kitchen Environment. (United States)

    Zhang, Han; McQueen, Rachel H; Batcheller, Jane C; Ehnes, Briana L; Paskaluk, Stephen A


    Within the kitchen the potential for burn injuries arising from contact with hot surfaces, flames, hot liquid, and steam hazards is high. The chef's uniform can potentially offer some protection against such burns by providing a protective barrier between the skin and the thermal hazard, although the extent to which can provide some protection is unknown. The purpose of this study was to examine whether fabrics used in chefs' uniforms were able to provide some protection against thermal hazards encountered in the kitchen. Fabrics from chefs' jackets and aprons were selected. Flammability of single- and multiple-layered fabrics was measured. Effect of jacket type, apron and number of layers on hot surface, hot water, and steam exposure was also measured. Findings showed that all of the jacket and apron fabrics rapidly ignited when exposed to a flame. Thermal protection against hot surfaces increased as layers increased due to more insulation. Protection against steam and hot water improved with an impermeable apron in the system. For wet thermal hazards increasing the number of permeable layers can decrease the level of protection due to stored thermal energy. As the hands and arms are most at risk of burn injury increased insulation and water-impermeable barrier in the sleeves would improve thermal protection with minimal compromise to overall thermal comfort.

  10. 77 FR 11577 - Notice of Inventory Completion: U.S. Department of the Interior, Bureau of Indian Affairs... (United States)


    ... yucca fiber apron, 1 basketry bowl, 2 cradleboards, 1 basketry tump strap, 3 ceramic bowls, 1 gourd... basketry mat fragments, 1 piece of plant fiber, 1 plant fiber blanket, 1 yucca fiber quid, 1 lot of cotton roving, 2 sandals, 1 wood spindle, 28 textile fragments, 3 textile wrappings, 4 wood lattice...

  11. Teachers' Talk about Robotics: Where Is the Mathematics? (United States)

    Savard, Annie; Highfield, Kate


    Programming and the use of robotics present affordances for mathematics learning with application across a broad range of ages. However, realising these affordances in the classroom requires educators to recognise and build apron these potential opportunities for learning. This paper reports one component of a larger study, examining teacher…

  12. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... able to see, hear and speak with your child at all times. A parent may be allowed in the room but will be required to wear a lead apron to prevent radiation exposure. The radiation ... child. Some imaging facilities may use general anesthesia or ...

  13. Loglines. January-February 2015 (United States)


    saline , protective gloves and utility aprons. Even DLA Disposition Services played a role in the early weeks of OUA by adding countries in western...headquartered in Washington, D.C., on a multi-day business development forum in Niger in early September before the Defense Department’s support to the “We

  14. Mexican Folkart for Children. (United States)

    Dominguez, Graciela; And Others

    Directions, suggested materials, and illustrations are given for making paper mache pinatas and masks, cascarones, Ojos de Dios, maracas, dresser scarf embroidery, burlap murals, yarn designs, paper plate trays, paper cut designs, the poppy, sarape aprons, and paper Mexican dolls. Filled with candy and broken, the pinata is used on most Mexican…

  15. Nano particles as the primary cause for long-term sunlight suppression at high southern latitudes following the Chicxulub impact - evidence from ejecta deposits in Belize and Mexico

    DEFF Research Database (Denmark)

    Vajda, Vivi; Ocampo, Adriana; Ferrow, Embaie


    Life on Earth was sharply disrupted 66 Ma ago as an asteroid hit the sea-floor in what is today Yucatan Peninsula, Mexico. Approximately 600 km3 of sedimentary rock were vapourized, ejected into the atmosphere and subsequently deposited globally as an ejecta apron and fallout layer. Proximal ejecta...

  16. 77 FR 10516 - Notice of Receipt of Requests To Voluntarily Cancel Certain Pesticide Registrations (United States)


    ... protected through or email. The Web site is an ``anonymous access'' system...-09036 RTU PCNB Seed Pentachloronitroben Protectant. zene. 005481-09037 Gustafson Apron...-00170 CB-38-2 For Insect Pyrethrins, Control. Piperonyl Butoxide. 010807-00101 Repco-Tox...

  17. Overview of Imaging Tests (United States)

    ... such tests are necessary Take precautions to limit radiation exposure during tests (for example, shielding vulnerable parts of the body, such as the ... the examiner protects the fetus from exposure to radiation by covering the woman’s abdomen with a lead apron. The risk to the fetus depends on ...

  18. 76 FR 2944 - Notice of Passenger Facility Charge (PFC) Approvals and Disapprovals (United States)


    ... of deicing truck. Acquisition of snow removal equipment. Decision Date: May 12, 2010. For Further... District Office, (701) 323-7385. Public Agency: Palm Beach Board of County Commissioners, West Palm Beach.... Snow removal equipment. Pavement management plan. Apron lighting. Runway 5/23 rehabilitation....

  19. Literature Review on Possible Alternatives to Tar for Antiskid Layers

    NARCIS (Netherlands)

    Xiao, Y.


    In airports, there are different areas such as runways, taxiways, aprons and parking areas. For runways, good skid resistance and water drainage of the surface layer is necessary. Tar, because of its good adhesion properties and other advantages as mentioned above, is widely used in thin, high skid

  20. 40 CFR 721.3 - Definitions. (United States)


    ... dermal contact with chemical substances of concern. Examples can include, but are not limited to: full... substances in the work area. Examples include, but are not limited to, chemical protective clothing, aprons... (i.e., positive response in assays for gene mutation, chromosomal aberrations, DNA damage and...

  1. 33 CFR Appendix A to Part 274 - Preventive Safety Measures in Handling of Pesticides (United States)


    ... protective clothing are rubber aprons, coveralls, chemical splash goggles, safety shoes, and hard hats. A... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Preventive Safety Measures in... Appendix A to Part 274—Preventive Safety Measures in Handling of Pesticides 1. Follow the label on...

  2. 33 CFR Appendix E to Part 273 - Preventive Safety Measures in Handling of Herbicides (United States)


    ... are rubber aprons, coveralls, chemical splash goggles, safety shoes and hard hats. A lightweight water... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Preventive Safety Measures in...—Preventive Safety Measures in Handling of Herbicides 1. Follow the label on each container before using...

  3. Ranging Behaviour of Commercial Free-Range Laying Hens. (United States)

    Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan


    In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

  4. A study on scattered dose in operation room by C-arm unit

    Energy Technology Data Exchange (ETDEWEB)

    An, Sung Min; Oh, Jung Hwan; Kim, Sung Chul [Gachon Gil College, Incheon (Korea, Republic of)


    This paper studied a C-arm's exposure condition and measured scatter rays by thickness and distance. This study reached the following conclusion. Approximately exposure dose for a patient using fluoroscopy is as follows: Mostly, an operating room was not shielding by lead and operator put on only apron without thyroid and facial part protection. 0.5 mmPb equivalent's apron shielded about 99% of scattered rays at 60 cm from x-ray tube. Scattered rays are depended on distance and thickness so operators are should be careful when using fluoroscopy by C-arm and if possible use high frequency equipment that has a large output.

  5. Aircraft Detection in High-Resolution SAR Images Based on a Gradient Textural Saliency Map (United States)

    Tan, Yihua; Li, Qingyun; Li, Yansheng; Tian, Jinwen


    This paper proposes a new automatic and adaptive aircraft target detection algorithm in high-resolution synthetic aperture radar (SAR) images of airport. The proposed method is based on gradient textural saliency map under the contextual cues of apron area. Firstly, the candidate regions with the possible existence of airport are detected from the apron area. Secondly, directional local gradient distribution detector is used to obtain a gradient textural saliency map in the favor of the candidate regions. In addition, the final targets will be detected by segmenting the saliency map using CFAR-type algorithm. The real high-resolution airborne SAR image data is used to verify the proposed algorithm. The results demonstrate that this algorithm can detect aircraft targets quickly and accurately, and decrease the false alarm rate. PMID:26378543

  6. Review of literature on local scour under plane turbulent wall jets (United States)

    Aamir, Mohammad; Ahmad, Zulfequar


    Stability of hydraulic structures is threatened by persistent scour downstream of the apron, which renders their foundations exposed. Jets issuing under the sluice gate are turbulent enough to cause significant scour. Extensive study of the jets is, therefore, necessary in order to understand the underlying hydraulics and provide remedial measures. In this paper, a comprehensive review of the investigations on local scour caused by wall jets is presented, including both the classical as well as the prevalent approach. Various aspects of the scour under wall jets have been explained, including the process of scouring, different parameters affecting the maximum scour depth, analysis of flow characteristics within the scour hole and on the apron, time variation of scour depth, rate of sediment removal, and scour depth estimation formulae.

  7. Optimisation need of dental radiodiagnostic procedures: results of effective dose evaluation from Rando phantom measurements

    Energy Technology Data Exchange (ETDEWEB)

    Borio, R.; Chiocchini, S.; Cicioni, R.; Degli Esposti, P.; Rongoni, A.; Sabatini, P.; Saetta, D.M.S. (Perugia Univ. (Italy). Health Physics Lab. Istituto Nazionale di Fisica Nucleare, Perugia (Italy)); Regi, L.; Caprino, G. (Perugia Univ. (Italy). Dept. of Radiology)


    Radiological examinations of different types are needed in dental practice both to make a correct diagnosis and to carry out an adequate therapy. Particularly in orthodentic practices, because of the youth of the majority of the patients, an assessment of the detriment to health (through the effective dose equivalent) caused by medical diagnostic exposure to ionising radiation is needed to make decisions about the optimisation of dental radiodiagnostic procedures. Experimental data from measurements on a Rando phantom were collected for the radiological examinations required for dental and for orthodontic practices (with and without protective apron and collar). The results show the effectiveness of the leaded apron and collar in all the examinations carried out, particularly in reducing thyroid dose. (author).

  8. [Surgical scrub: evaluation of its adequacy in preventing biological risks in surgery: I. Its use in surgery]. (United States)

    Paz, M S; Lacerda, R A; Monteiro, C E; da Conceição, V P


    The study elaborated approaches for adequate use of the surgical scrub and it evaluated, through systematized observation, the performance of the surgical team during the surgery. The adopted procedure was very valid, allowing to recognize positive and problematic aspects. Except the protecting glasses, all the other components of the surgical scrub were used. The subject located in the use form, where caps and masks were more problematic among anaesthesists and circulate nurses; apron and gloves among surgeons and, mainly, scrub nurses.

  9. National Program for Inspection of Non-Federal Dams. Chicopee Reservoir (MA 00720), Connecticut River Basin, Chicopee, Massachusetts. Phase I Inspection Report. (United States)


    two span steel framed footbridge with a concrete deck and metal railing spans over the upstream chute section (see Photo No. 5). The depth of flow in...the section of the apron upstream of the footbridge to the spillway is in good condition. Erosion has occurred at the interface of the first reach of...surface cracking at the top of the intermediate concrete pier, the footbridge is in good condition with no evidence of spalls or erosion. The steel

  10. National Dam Safety Program. Seneca Lake Dam (NJ00768), Delaware River Basin, Lubbers Run, Sussex County, New Jersey. Phase 1 Inspection Report. (United States)


    CFIGURET2 CONCRET- B MASONRY SlOE WALL TIMBER a PLANK FOOTBRIDGE E L. 85 6,5 EL. 855 I7 I EL 854 25 9FLASHBOARD--/ I - 30 12" CONCRETE APRON NATURAL...February,1981 View of Seepage and Outlet Channel February 1981 View of Spillway and Footbridge February 1981 View of Downstream Road Bridge diI CHECk LIST

  11. A Green Leaf on the Big Tree

    Institute of Scientific and Technical Information of China (English)


    "WITH a dyed darkish-blue apron" was myself portrait when I first entered literarycircles. My hometown Chumen in Yuhuan is asmall town by the sea, a land of fish and ricein the southern reaches of the ChangjiangRiver. The gong and drum for the Liberationsounded in my childhood. I was infatuated bybooks then; the wing of ideas often entered mydreams like beautiful butterflies.

  12. Enxerto aorto-femoral por via laparoscópica: modelo experimental Laparoscopic aortofemoral bypass: experimental model

    Directory of Open Access Journals (Sweden)

    Pedro E. B. Fusco


    Full Text Available OBJETIVO: Verificar a exeqüibilidade de enxerto aorto-femoral por via laparoscópica. MÉTODO: Operamos porco de 75 kg sob anestesia geral. Empregando a técnica do avental (apron de Dion, expusemos a aorta por laparoscopia. Brevemente, em decúbito dorsal horizontal, dissecamos um "avental" do peritônio parietal esquerdo. A dissecção prosseguiu com rotação medial do cólon esquerdo. O avental, posteriormente fixo à linha mediana, serviu de anteparo às alças intestinais. Pinçamos a aorta e realizamos enxerto aorto-femoral com o tempo abdominal totalmente laparoscópico. RESULTADO: O enxerto foi realizado com sucesso, e o fluxo sangüíneo na prótese foi demonstrado através da incisão femoral. CONCLUSÃO: O enxerto aorto-femoral experimental laparoscópico é exeqüível através da exposição com a técnica do avental.OBJECTIVE: To verify the feasibility of the aortofemoral laparoscopic bypass. METHOD: We operated on a 75-kg pig under general anesthesia. The aorta was exposed using Dion's "apron" technique. Briefly, the animal was placed in supine position and the parietal peritoneum was dissected away from the left of the midline. The dissection proceeded with medial rotation of the left colon. This constructed apron (parietal peritoneum, left colon and mesocolon, in continuity was sutured to the midline. It served to keep the sliding bowel away from the operative field. After clamping the aorta, we performed an aortofemoral bypass with a totally laparoscopic abdominal time. RESULT: The bypass was successfully performed, and the blood flow through the prosthesis was considered adequate when verified at the femoral incision. CONCLUSION: The experimental laparoscopic aortofemoral bypass is feasible using the apron exposure technique.

  13. Department of the Navy FY 1990/FY 1991 Biennial Budget Estimates. Military Construction and Family Housing Program FY 1991. Justification Data Submitted to Congress (United States)


    stations; upgrade thermal insulation on 24,600 lineal feet of existing steam distribution pipe and 11,050 lineal feet of existing condensate pipe; install...08/86 MiTOTAL 4.a 3C S. MA•JOR PL.ANNED NEXT THREE YEARS: 113 20 ’AIRCRAFT PARKION APRON 112.SFT SC 12.760 21C.05 FO I NA PROT AC HANGAR SHP LS 3

  14. Twelfth Annual Report of Operations under the Airport and Airway Development Act. (United States)


    Expand apron. Rock Island County Quad City Mount Vernon 08 $ 338,670 Apply porous friction surface Mount Vernon Airport R/W 5-23; rehabilitate runway...lights. Authority Mount Vernon -Outland (COMMUTER) Peoria 09 $ 554,390 Construct and light airport entrance Greater Peoria Airport road. Authority...taxiway lighting. Airport Board Owensboro-Daviess County (COMMUTER) Somerset 07 $ 13,500 Replace portion of lighting on R/W 4-22. Somerset -Pulaski County

  15. Finite Element Analysis on the Pre-load Structures of the Central Solenoid for the HT-7U Device

    Institute of Scientific and Technical Information of China (English)


    The central solenoid is an important part of the HT-7U device. In this paper, the computational analysis of the stress and the displacement on the pre-load structures of the central solenoid have been made by the finite element analysis system COSMOS/M2.0 under room and/or operating temperature. According to the analytical results, the clip aprons and compression plates are all satisfied with safety design criteria.

  16. Dynamics of Supercritical Flows (United States)


    safety shoes, leather gloves, and ear muffs (noise protection as required). Cryogenic PPE: Cryogenic gloves, Cryogenic Body Apron, Full-Face shield...the fluid in the dark core assuming the shape of an inverted mushroom . The excitation is so violent that the dark core is fully mixed by the time the...vortical structures involving the inner jet flow were ejected in an inverted mushroom -like fashion at the excitation frequency (~3 kHz). Up to the

  17. Report of Accomplishments under the Airport Improvement Program. (United States)



  18. Environmental Assessment. Proposed Sahara Mustard Control on the Barry M. Goldwater Range - East (United States)


    also mesquite ( Prosopis spp.), palo verde (Parkinsonia spp.), and ironwood (Olneya tesota) trees along washes. Barrel cactus (Ferocactus spp...It consists of a corrugated sheet metal water collection apron that diverts rainfall to a 5000 gallon subterranean ring tank reservoir. Water from...River following heavy runoff events. There are no intermittent or perennial streams or floodplains within the treatment areas. 3.3.3 Groundwater

  19. Environmental Assessment for the Minuteman III Propulsion System Rocket Engine Life Extension Program (United States)


    layers) depleted in calcium carbonate but enriched in aluminum-and iron -bearing minerals. ä Aridisol – Aridisols are dry, desert like soils that...characteristic vegetation. However, in much of this area, mesquite ( Prosopis ) grows in open stands among the grasses. M313 – Arizona – New Mexico Mountains...flux Inhalation, contact, and ingestion. Safety glasses, apron, and only low temperature solder irons are used. BUILD UP • 2-butoxyethanol (1st

  20. Depositional Patterns and Oil/Gas Accumulation Features of Sha-3 Member Turbidites in Dongying Depression, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    BaiGuoping; ZhangShanwen


    Recent exploration results indicate that a significant exploration potential remains in the Dongying Depression of the Bohai Bay Basin and the undiscovered oil and gas are largely reservoired in subtle traps including turbidite litholigeal traps of the Sha-3 Member. In order to effectively guide the exploration program targeting turbidites, this study will focus on the depositional models of the Sha-3 Member turbidites and oil/gas accumulation characteristics in these turbidites. Two corresponding relationships were found. One is that the East African Rift Valley provides a modem analog for the depositionai systems in the Dongying Depression. The other is that the depositional models of line-sourced slope aprons, single point-source submarine fan and multiple source romp turbidite, established for deep.sea turbidites, can be applied to interpret the depositional features of the turbidite fans of three differant origins: slope turbidite aprons, lake floor turbidite fans and delia-fed turbidite fans in the Sha-3 Member. Updip sealing integrity is the key factor determining whether oil/gas accumulates or not in the slope aprons and lake floor fans. The factors controlling oil/gas migration and accumulation in the delta-ted turbidite fans are not very clear. Multiple factors rather than a single factor probably played significant roles in these processes.

  1. A complicated story of frost and wind: Present-day gully activity within the north polar erg, Mar (United States)

    Diniega, Serina; Hansen, Candice; Allen, Amanda; Grisby, Nathan; Li, Zheyu Joey


    Analyses of high-resolution observations have shown that the dunes within the martian north polar erg (AKA Olympia Undae) are currently very active on seasonal and yearly timescales, with 20-60% of the dunes within five polar dune fields undergoing the formation of alcove-apron features each Mars year. Previous studies have hypothesized formation mechanisms, based on observations of when new alcove and alcove-apron features form within an individual field through one Mars year. However, results are ill-constrained (and thus different hypotheses have been proposed) as the polar hood and winter night mean very few images are taken during the actual period of activity. In this study, we mitigate this limitation by examining several fields over several Mars years -- thus bringing aggregated results as well as detailed correlation checks against environmental conditions and seasonal processes to bear on the problem. From this, we propose a new process that appears consistent with all observations: (1) small alcoves form along the dune brink in the autumn (under the polar hood) due to instabilities induced by the night-formation and morning-sublimation of frost. As autumn progresses, the seasonal frost layer builds over the altered dune slope. (2) In the early spring, sublimation activity is concentrated and/or enhanced over these alcoves, causing further erosion and the formation of larger alcove-apron features. From the planform dimensions of the newly formed alcoves, we can estimate the volume of sand moved down the dune slope during one period of activity and estimate the aeolian sediment flux by looking at how quickly the alcoves are erased. We find that, over a Mars year, the amount of material moved via alcove-apron activity and via the wind are both comparable to aeolian sand flux estimates over dunes within lower-latitude regions of Mars. Thus it appears that the formation of alcoves-aprons is a significant mechanism for dune advancement and evolution within the

  2. Seismic Demands for Pile-Supported Wharf Structures with Batter Piles

    Directory of Open Access Journals (Sweden)

    Rouhollah Amirabadi


    Full Text Available This study develops an optimal Probabilistic Seismic Demand Model (PSDM for pile-supported wharves whit batter plies. Four bins with twenty non-near-field ground motions and three typical pile-supported wharf structures from western United States ports are used to determine an optimal PSDM by using Probabilistic Seismic Demand Analysis (PSDA. PSDA is used to compute the relationship between Engineering Demand Parameters (EDPs and earthquake Intensity Measures (IMs. An optimal PSDM should be practical, sufficient, effective and efficient-all tested through several IM-EDP pairs. It has been found that for these types of structures, the optimal model comprises a spectral IM, such as spectral acceleration and one of several EDPs. These EDPs are considered for local (moment curvature ductility factor, intermediate (displacement ductility factor and horizontal displacement of embankment and global (differential settlement between deck and behind land response quantities. The considered PSDMs are a critical component in performance-based seismic design and seismic risk assessment. Results can be used in probabilistic framework for performance-based design developed by Pacific Earthquake Engineering Research (PEER center.

  3. Sea floor engineering geomorphology: recent achievements and future directions (United States)

    Prior, David B.; Hooper, James R.


    New mapping technology is providing perspectives of the sea floor "as if there were no ocean", revealing that ocean floors exhibit a wide variety of relief, sediment properties, and active geologic processes such as erosion, faulting, fluid expulsion, and landslides. The development of coastal and offshore resources, such as oil and gas and minerals, involves sea floor engineering in remote, complex, and sometimes hazardous environments. Optimum engineering design and construction practice require detailed surveys of sea floor geomorphology, geologic conditions on the sea bed and to various depths beneath it, combined with geotechnical properties of the sediments and oceanographic information. Integrated site survey models attempt to predict conditions and process frequencies and magnitudes relevant to the engineering design lifetimes of sea floor installations, such as cables, pipelines, production platforms, as well as supporting coastal infrastructure such as jetties, wharves, bridges and harbors. Recent use of deep water areas for oil and gas production, pipelines, and cable routes are also showing that the "world's greatest slopes", beyond the continental shelves contain exciting, exotic, and enigmatic geomorphological features and processes. Safe and cost-effective engineering use of these regions depends upon exciting new technical and conceptual advances for understanding sea floor geomorphology — a task which has barely begun.


    Institute of Scientific and Technical Information of China (English)


    Bacteria numbers in water of coastal shellfish culture area around Qingdao were examined in April, August and October 1998 respectively. The results showed that the total numbers of heterotrophic and coliform bacteria in waters of the area and the specific geographical area varied with seasons. The highest populations were recorded during summer, I.e. 1.0×104~4.5×106cell/ml and 3.0×100~2.4×103cell/100ml, and with average values of 1.61×105cell/ml and 1.24×102cell/100ml respectively. The second highest populations occurred in autumn, and the lowest were in spring. The numbers of coliform bacteria were relatively low in waters near the mouths of bays and open part of the shellfish culture area, while those in waters near the estuaries of big rivers, wharves, navigation routes or the area in front of downtown areas were much higher than other areas. Single-index assessment of the environment quality of shellfish culture was made to indicate that the water sanitary quality in most of these areas are very good, however, some parts were serious polluted by the faeces of warm-blood animals. These results provided theoretical reference for the programming and organizing of shellfish culture.

  5. The sensory innervation of the human pharynx: searching for mechanoreceptors. (United States)

    de Carlos, F; Cobo, J; Macías, E; Feito, J; Cobo, T; Calavia, M G; García-Suárez, O; Vega, J A


    The coordinate neural regulation of the upper airways muscles is basic to control airway size and resistance. The superior constrictor pharyngeal muscle (SCPM) forms the main part of the lateral and posterior walls of the pharynx and typically is devoid of muscle spindles, the main type of proprioceptor. Because proprioception arising from SCPM is potentially important in the physiology of the upper airways, we have investigated if there are mechanical sensory nerve endings substitute for the muscle spindles. Samples of human pharynx were analyzed using immunohistochemistry associated to general axonic and Schwann cells markers (NSE, PGP 9.5, RT-97, and S100P), intrafusal muscle fiber markers, and putative mechanical sense proteins (TRPV4 and ASIC2). Different kinds of sensory corpuscles were observed in the pharynx walls (Pacini-like corpuscles, Ruffini-like corpuscles, spiral-wharves nerve structures, and others) which are supplied by sensory nerves and express putative mechanoproteins. No evidence of muscle spindles was observed. The present results demonstrate the occurrence of numerous and different morphotypes of sensory corpuscles/mechanoreceptors in human pharynx that presumably detect mechanical changes in the upper airways and replace muscle spindles for proprioception. Present findings are of potential interest for the knowledge of pathologies of the upper airways with supposed sensory pathogenesis.

  6. Morphology of nerve endings in vocal fold of human newborn. (United States)

    Gonçalves da Silva Leite, Janaina; Costa Cavalcante, Maria Luzete; Fechine-Jamacaru, Francisco Vagnaldo; de Lima Pompeu, Margarida Maria; Leite, José Alberto Dias; Nascimento Coelho, Dulce Maria; Rabelo de Freitas, Marcos


    Sensory receptors are distributed throughout the oral cavity, pharynx, and larynx. Laryngeal sensitivity is crucial for maintaining safe swallowing, thus avoiding silent aspiration. Morphologic description of different receptor types present in larynx vary because of the study of many different species, from mouse to humans. The most commonly sensory structures described in laryngeal mucosa are free nerve endings, taste buds, muscle spindles, glomerular and corpuscular receptors. This study aimed at describing the morphology and the distribution of nerve endings in premature newborn glottic region. Transversal serial frozen sections of the whole vocal folds of three newborns were analyzed using an immuno-histochemical process with a pan-neuronal marker anti-protein gene product 9.5 (PGP 9.5). Imaging was done using a confocal laser microscope. Nerve fiber density in vocal cord was calculated using panoramic images in software Morphometric Analysis System v1.0. Some sensory structures, i.e. glomerular endings and intraepithelial free nerve endings were found in the vocal cord mucosa. Muscle spindles, complex nerve endings (Meissner-like, spherical, rectangular and growing) spiral-wharves nerve structures were identified in larynx intrinsic muscles. Nervous total mean density in vocal cord was similar in the three newborns, although they had different gestational age. The mean nerve fiber density was higher in the posterior region than anterior region of vocal cord. The present results demonstrate the occurrence of different morphotypes of sensory corpuscles and nerve endings premature newborn glottic region and provide information on their sensory systems.

  7. Development of measurement method using TLD for workers occupation personally exposed to 125Ⅰ seed source in the implant%热释光剂量计测量125Ⅰ粒子源植入中职业人员剂量方法研究

    Institute of Scientific and Technical Information of China (English)

    罗素明; 何志坚; 袁继龙; 岳保荣; 尉可道


    implantation of 125Ⅰ seed sources.Methods The experiments with 60Co γ-rays were carried out for the stability.A group of TLD chips was exposed to 125Ⅰ seed sources to establish standard dose curve for air kerma.During the 125Ⅰ seed implantation, the TLD chips were pasted to 13 locations like thyroid inside and outside the lead aprons worn by occupational workers to measure average absorbed dose and calculate the absorbed doses and effectives to organs and tissues.Results For 3 cases of prostate cancers with implantation of 125Ⅰ seeds, the worker's organs and tissues received the absorbed dose 0.02 -3.80 μ Gy and effective dose 0.06- 1.81 μSv outside lead aprons and the highest absorbed dose 2.35 μ Gy and effective 0.02 μSv inside lead aprons, respectively, with more than 65.9% of rays shielded.For 3 cases of brain cancers with implantation of 125Ⅰ seeds, the workers received the absorbed dose 0.23 - 11.31 μGy and effective dose 0.88 - 4.07 μSv outside lead aprons and the highest absorbed dose 2.22 μ Gy and effective dose 0.09 μSv inside lead aprons, respectively, with more than 54.5% of rays shielded.For 3 cases of lung cancers with implantation of 125Ⅰ seeds, the workers received the absorbed dose 0.03 - 14.78 μGy and effective dose 0.35 -7.59 μSv outside lead aprons and the highest absorbed dose 4.09 μGy and effective 0.22 μSv inside lead aprons, respectively, with more than 58.4% of rays shielded.For 2 cases of mediastinum cancers with implantation of 125Ⅰseeds, the workers received the absorbed dose 0.06 - 74.91 μGy and effective dose 0.83 - 17.96 μSv outside lead aprons and the highest absorbed dose 10.29 μGy and effective 0.5 μSv inside lead aprons, respectively, with more than 85% of rays shielded.For one case of ovary cancer with implantation of 125Ⅰ seeds, the worker received the absorbed dose 0.09 - 14.29 μGy and effective dose 2.40 - 4.50 μSv outside lead aprons and the highest absorbed dose 7.77 μGy and effective 0.12 μSv inside

  8. A new model evaluating Holocene sediment dynamics: Insights from a mixed carbonate-siliciclastic lagoon (Bora Bora, Society Islands, French Polynesia, South Pacific) (United States)

    Isaack, Anja; Gischler, Eberhard; Hudson, J. Harold; Anselmetti, Flavio S.; Lohner, Andreas; Vogel, Hendrik; Garbode, Eva; Camoin, Gilbert F.


    Mixed carbonate-siliciclastic lagoons of barrier reefs provide great potential as sedimentary archives focusing on paleoenvironmental and paleoclimatic changes as well as on event deposition. Sediment sources include lagoonal carbonate production, the marginal reef and the volcanic hinterland. Mixed carbonate-siliciclastic continent-attached coastal lagoons have been intensively studied, however, their isolated oceanic counterparts have been widely disregarded. Here, we present a new model of Holocene sediment dynamics in the barrier-reef lagoon of Bora Bora based on sedimentological, paleontological, geochronological and geochemical data. The lagoonal succession started with a Pleistocene soil representing the Lowstand Systems Tract. As the rising Holocene sea inundated the carbonate platform, peat accumulated locally 10,650-9400 years BP. Mixed carbonate-siliciclastic sedimentation started ca. 8700-5500 years BP and represents the Transgressive Systems Tract. During that time, sediments were characterized by relatively coarse grain size and contained high amounts of terrestrial material from the volcanic hinterland as well as carbonate sediments mainly produced within the lagoon. Siliciclastic content decreases throughout the Holocene. After the rising sea had reached its modern level, sand aprons formed between reef crest and lagoon creating transport pathways for reef-derived material leading to carbonate-dominated sedimentation ca. 6000-3000 years BP during the Highstand Systems Tract. However, mainly fine material was transported and accumulated in the lagoon while coarser grains were retained on the prograding sand apron. From ca. 4500-500 years BP, significant variations in grain-size, total organic carbon as indicator for primary productivity, Ca and Cl element intensities as qualitative indicators for carbonate availability and lagoonal salinity are seen. Such patterns could indicate event (re-)deposition and correlate with contemporaneous event deposits

  9. Learning the easy way. (United States)


    This article describes the program activities of a 1-day seminar and training course that was organized by the Japan International Cooperation Agency (JICA). Participants included high-ranking government officials from education directorates from 12 countries and officers from the National Women's Education Center. The training course relied on two innovative IEC materials developed by JOICFP. The two IEC materials were portable, durable kits that provided visual guides to learning about reproductive health (RH). The Magnel Kit includes a metal white board with almost life-size illustrations of male and female reproductive organs and magnetized vinyl images that teach about the menstrual cycle, pregnancy stages, contraception, and sexually transmitted diseases. Maggie the Apron is a durable apron with transparent pockets for placing cards with images relating to menstruation, pregnancy, and contraception. The apron is light in weight, cost-effective, and easily folded for storage and portability. Participants were particularly interested in the use of the two IEC materials in adolescent sexual health education. The clear visual materials offer the option of teaching according to the level of understanding of the audience. The materials can be used in any country, since there are no printed texts or narration. The training introduced participants to a community-based approach to family planning and maternal-child health services, which were successful in Japan for raising the level of health. The approach is used by JOICFP in its program efforts in developing countries. The training introduced participants to the role of community women in promoting RH through the presentation of a case study from Bangladesh. Participants watched the JOICFP still-image video "Moni's Milestone," a story about a woman's life in Bangladesh, and a video on the family planning movement in Japan, "First Step in Family Planning in Japan."

  10. Cardiac catheterization: impact of face and neck shielding on new estimates of effective dose. (United States)

    von Boetticher, Heiner; Lachmund, Jörn; Hoffmann, Wolfgang


    Optimization of radiation protection devices for the operator is achieved by minimizing the effective dose (E) on the basis of the recommendations of Publications 60 and 103 of the International Commission on Radiological Protection (ICRP). Radiation exposure dosimetry was performed with thermoluminescence dosimeters using one Alderson phantom in the patient position and a second one in the typical position of the operator. Various types of protective clothing as well as fixed leaded shieldings (table mounted shielding and overhead suspended shields) were considered calculating E. Shielding factors for protective equipment can readily be misinterpreted referring to the reduction of the effective dose because fixed protective barriers as well as radiation protection clothing are shielding only parts of the body. With the ICRP 103 approach relative to the exposure without lead protection, a lead apron of 0.35 or 0.5 mm thickness reduces E to 14.4 or 12.3%, respectively; by using an additional thyroid collar, these values are reduced to 9.7 or 7.5%. A thyroid collar reduces the effective dose by more than an increase of the lead equivalency of the existing apron. Wearing an apron of 0.5 mm lead-equivalent with a thyroid collar and using an additional side shield, E decreases to 6.8%. Using both a fixed side and face shield decreases E to 2.0%. For protective garments including thyroid protection, the values of the effective dose in cardiac catheterization are 47-106% higher with ICRP 103 than with ICRP 60 recommendations. This is essentially caused by the introduction of new factors for organs in the head and neck region in ICRP 103.

  11. Geologic Mapping of Ascraeus Mons, Mars (United States)

    Mohr, K. J.; Williams, D. A.; Garry, W. B.


    Ascraeus Mons (AM) is the northeastern most large shield volcano residing in the Tharsis province on Mars. We are funded by NASA's Mars Data Analysis Program to complete a digital geologic map based on the mapping style. Previous mapping of a limited area of these volcanoes using HRSC images (13-25 m/pixel) revealed a diverse distribution of volcanic landforms within the calderas, along the flanks, rift aprons, and surrounding plains. The general scientific objectives for which this mapping is based is to show the different lava flow morphologies across AM to better understand the evolution and geologic history.

  12. Annual Report (12th) of Accomplishments Under the Airport Improvement Program. Fiscal Year 1993 (United States)



  13. The proof and the pudding what mathematicians, cooks, and you have in common

    CERN Document Server

    Henle, Jim


    Tie on your apron and step into Jim Henle's kitchen as he demonstrates how two equally savory pursuits-cooking and mathematics-have more in common than you realize. A tasty dish for gourmets of popular math, The Proof and the Pudding offers a witty and flavorful blend of mathematical treats and gastronomic delights that reveal how life in the mathematical world is tantalizingly similar to life in the kitchen. Take a tricky Sudoku puzzle and a cake that fell. Henle shows you that the best way to deal with cooking disasters is also the best way to solve math problems. Or take an L-shaped billi

  14. Modelling and Analysis of the Gobustan: Sundial Observatory (United States)

    Rustamov, Abasali; Rustamova, Gunay


    The well-known boat carvings of Gobustan Rock Carvings Preserve with a crosses or strokes on board and sun image on the prow are calendrical inscriptions. Moreover, the "year boat" from eastern niche of Stone No.1 used in conjunction with a gnomon, to indicate solar time periods. The bull, ram, ibex and some time boat with the sinuous brook carved on the niche apron evidence relevant to the work zodiac creation. Decisive fact for this conclusion is the formation in the northern niche silhouette lion head, eating the sun in the summer.

  15. Dødsulykker ved bygningsbrande

    DEFF Research Database (Denmark)

    Leth, Peter Mygind; Gregersen, Markil Ebbe Gregers; Sabroe, Svend


    (66 men and 70 women), 1988-93: 363 (212 men and 150 women), mostly due to an increase in tobacco-smoking related fire accidents. In 1988-93 the three common causes of housefire deaths were tobacco-smoking, often in combination with alcohol intoxication or handicap (51%), cooking-accidents (10......%) and accidents with candles (9%). The largest risk groups were chronic alcoholics, handicapped and elderly people. In conclusion, warnings should be issued against smoking in bed and use of loose-fitting clothing while cooking on an open fire. Protective aprons and devices for use while smoking, self...

  16. 美国批准Cruiser可用于水稻上

    Institute of Scientific and Technical Information of China (English)




  17. Uranium Mill Tailings Remedial Action Project (UMTRAP), Slick Rock, Colorado, Revision 1, Volume 3. Calculations, Final design for construction

    Energy Technology Data Exchange (ETDEWEB)



    Volume three contains calculations for: site hydrology--rainfall intensity, duration, and frequency relations; site hydrology-- probable maximum precipitation; erosion protection--rock quality evaluation; erosion protection--embankment top and side slope; erosion protection--embankment toe apron; erosion protection-- gradations and layer thicknesses; Union Carbide site--temporary drainage ditch design; Union Carbide site--retention basin sediment volume; Union Carbide site--retention basin sizing; Burro Canyon site temporary drainage--temporary drainage facilities; and Union Carbide site temporary drainage--water balance.

  18. Mass wasting features in Juventae Chasma, Mars (United States)

    Sarkar, Ranjan; Singh, Pragya; Porwal, Alok; Ganesh, Indujaa


    Introduction : We report mass-wasting features preserved as debris aprons from Juventae Chasma. Diverse lines of evidence and associated geomorphological features indicate that fluidized ice or water within the wall rocks of the chasma could be responsible for mobilizing the debris. Description : The distinctive features of the landslides in Juvenate Chasma are: (1) lack of a well-defined crown or a clear-cut section at their point of origin and instead the presence of amphitheatre-headed tributary canyons; (2) absence of slump blocks; (3) overlapping of debris aprons; (4) a variety of surface textures from fresh and grooved to degraded and chaotic; (5) rounded lobes of debris aprons; (6) large variation of sizes from small lumps (~0.52 m2) to large tongue shaped ones (~ 80 m2); (7) smaller average size of landslides as compared to other chasmas; and (8) occasional preservation of fresh surficial features indicating recent emplacement. Discussion : Amphitheatre-headed tributary canyons, which are formed due to ground water sapping, indicate that the same was responsible for wall-section collapse, although a structural control cannot be completely ruled out. The emplacement of the mass wasting features preferentially at the mouths of amphitheatre-headed tributary canyons along with the rounded flow fronts of the debris suggest fluids may have played a vital role in their emplacement. The mass-wasting features in Juventae Chasma are unique compared to other landslides in Valles Marineris despite commonalities such as the radial furrows, fan-shaped outlines, overlapping aprons and overtopped obstacles. The unique set of features and close association with amphitheatre-headed tributary canyons imply that the trigger of the landslides was not structural or tectonic but possibly weakness imparted by the presence of water or ice in the pore-spaces of the wall. Craters with fluidized ejecta blankets and scalloped depressions in the surrounding plateau also support this

  19. Evaluation and Response of Aged Flexible Airfield Pavements at Ambient Temperatures Using the Falling Weight Deflectometer (United States)


    3) accessibilty to the airfield, especially during the day, was virtually unlimited, 4) the entire airfield, excluding parking aprons, was comprised...role. 135 LU C4 Cy! C CU 0 C*4O LU - CC-) 0 - AUla j? cc IL 0 01 tn in P4 4 Lui ( tn to4- .~0 N U LLL 0m Sr CHAPTER 6 ANALYSES OF FIELD MEASURED FWD...tempera- tures were virtually the same for both sites. This showed that as the degree of cracking in the asphalt concrete diminished, temperature

  20. Airfield Pavement Evaluation Report. Godman Army Airfield Fort Knox, Kentucky (United States)


    Emergency Minimum Full Capacity 90,00 (’,00 ^o,oo 1.0,00 Taxiway U 3e er-l ed ti guros 1-1/2 for evaluation Asphaltic "oncrete Portland...Mini" as Full Capacity :.r,0Q 35,00 •o.oc 25,00 north and south apron ext. Ho e;i •d f| guros 1-1/2 for evaluation Aßphaltic I’oniT-t

  1. Installation Restoration Program. Phase 1. Records Search for Air Force Reserve and Air National Guard Facilities at General Billy Mitchell Field, Milwaukee, Wisconsin (United States)


    earthen ditch. The water then flows north, past the aircraft parking apron, ultimately draining into "Bailey’s Pond," a marshland located at the low lying...drainage ditch or stream bed sediments . Flooding at the time of the spill would ensure a high dilution factor of any contaminants which were not...W96000M6Daovd’~~ Chromiuni.Total 013 <Residue.Total 000 H00400 u~ Chromium VI 01032" RiaeFlerte(fS 70300 3’, G U 3 Te erue 0 0 0 1 0 ____ 01042e

  2. Emissions of NOx, particle mass and particle numbers from aircraft main engines, APU's and handling equipment at Copenhagen Airport (United States)

    Winther, Morten; Kousgaard, Uffe; Ellermann, Thomas; Massling, Andreas; Nøjgaard, Jacob Klenø; Ketzel, Matthias


    This paper presents a detailed emission inventory for NOx, particle mass (PM) and particle numbers (PN) for aircraft main engines, APU's and handling equipment at Copenhagen Airport (CPH) based on time specific activity data and representative emission factors for the airport. The inventory has a high spatial resolution of 5 m × 5 m in order to be suited for further air quality dispersion calculations. Results are shown for the entire airport and for a section of the airport apron area ("inner apron") in focus. The methodology presented in this paper can be used to quantify the emissions from aircraft main engines, APU and handling equipment in other airports. For the entire airport, aircraft main engines is the largest source of fuel consumption (93%), NOx, (87%), PM (61%) and PN (95%). The calculated fuel consumption [NOx, PM, PN] shares for APU's and handling equipment are 5% [4%, 8%, 5%] and 2% [9%, 31%, 0%], respectively. At the inner apron area for handling equipment the share of fuel consumption [NOx, PM, PN] are 24% [63%, 75%, 2%], whereas APU and main engines shares are 43% [25%, 19%, 54%], and 33% [11%, 6%, 43%], respectively. The inner apron NOx and PM emission levels are high for handling equipment due to high emission factors for the diesel fuelled handling equipment and small for aircraft main engines due to small idle-power emission factors. Handling equipment is however a small PN source due to the low number based emission factors. Jet fuel sulphur-PM sensitivity calculations made in this study with the ICAO FOA3.0 method suggest that more than half of the PM emissions from aircraft main engines at CPH originate from the sulphur content of the fuel used at the airport. Aircraft main engine PN emissions are very sensitive to the underlying assumptions. Replacing this study's literature based average emission factors with "high" and "low" emission factors from the literature, the aircraft main engine PN emissions were estimated to change with a

  3. Development of gonad protectors to be used in children radiology from recycled materials; Desenvolvimento de protetores de gonadas para uso em radiologia pediatrica a partir de materiais reciclados

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, C.H.S.; Teixeira, G.J.; Peixoto, J.G.P., E-mail: [Instituto de Radioprotecao e Dosimetria, (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Menezes, I.V.; Medeiros, D.O.; Nunes, M.M.; Pinheiro, R.A.; Bernardes, P.M.B. [Hospital Copa D' Or, Rio de Janeiro, RJ (Brazil); Oliveira, D. [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)


    The use of medical radiology as a diagnostic tool has become a common practice and its benefits are undeniable, however, the radiological protection of patients has become a constant concern of the international community. Since children have a longer life expectancy, the risks of stochastic effects increase significantly. Thus, this study developed and designed gonads protectors, taking into account the anatomy, dimensions and ages of pediatric patients, reducing exposure to the primary beam by 94%. Furthermore, as a result of a secondary objective,success was obtained in reusing discarded as defective aprons. (author)

  4. Methodology of high dose research in medical radiodiagnostic; Metodologia de investigacao de doses elevadas em radiodiagnostico medico

    Energy Technology Data Exchange (ETDEWEB)

    Barboza, Adriana E.; Martins, Cintia P. de S., E-mail: [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)


    This work has as main purpose to study occupational exposure in diagnostic radiology in medical cases of high doses recorded in 2011 at the national level . These doses were recorded by monitoring individual of the occupationally exposed individuals (OEI's). This monitoring of the doses received by ionizing radiation has as main objective to ensure that the principle of dose limitation is respected. In this study it were evaluated doses of 372 OEI's radiology in different Brazilian states. Doses were extracted from the database of Sector Management Doses of the Institute for Radioprotection and Dosimetry - IRD/CNEN-RJ, Brazil. The information from the database provide reports of doses from several states, which allows to quantify statistically, showing those with the highest doses in four areas: dose greater than or equal to 20 mSv apron and chest and dose greater than or equal to 100 mSv apron and chest. The identification of these states allows the respective Sanitary Surveillance (VISA), be aware of the events and make plans to reduce them. This study clarified the required procedures when there is a record of high dose emphasizing the importance of using protective radiological equipment, dosimeter and provide a safety environment work by maintaining work equipment. Proposes the ongoing training of professionals, emphasizing the relevance of the concepts of radiation protection and the use of the questionnaire with their investigative systematic sequence, which will allow quickly and efficiently the success the investigations.

  5. Evaluation of radiological protection and dose of skin entrance in paediatric dentistry examinations; Avaliacao da protecao radiologica e da dose de entrada na pele em exames de odontologia pediatrica

    Energy Technology Data Exchange (ETDEWEB)

    Khoury, Helen Jamil [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear; Vasconcelos, Flavia Maria Nassar de [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Silveira, Marcia Maria Fonseca da [Universidade de Pernambuco (UPE), Recife, PE (Brazil). Fac. de Odontologia; Couto, Geraldo Bosco Lindoso [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Fac. de Odontopediatria; Brasileiro, Izabela Vanderley


    In this work the radiological protection conditions and dose at the entrance of pediatric patients undergoing dental intraoral radiographs were evaluated. The study was conducted in two clinics of the dentistry course at the Federal University of Pernambuco, Recife, PB, Brazil, equipped with conventional X-ray apparatus, with 60 and 70 kV. 254 exams of 113 patients between the ages of 3 to 12 years were evaluated. The skin entrance dose was estimated using TLD-100 thermoluminescent dosemeters. During the examination were also recorded information regarding the time of exposure, radiographic technique used, use of thyroid protectors and lead apron, angle and distance of the cone Locator to the patient's skin. The results showed that the input skin doses ranged from 0.3 mGy to 10mGy. The lead apron was used in 71% of exams while the thyroid shield was only used in 58% of the exams. The exposure times ranged from 0,5s to 1,5s. From the results it can be concluded that the radiological procedures are not optimized and that in some cases the patient dose is high.

  6. Ground movement at Somma-Vesuvius from Last Glacial Maximum (United States)

    Marturano, Aldo; Aiello, Giuseppe; Barra, Diana; Fedele, Lorenzo; Morra, Vincenzo


    Detailed micropalaeontological and petrochemical analyses of rock samples from two boreholes drilled at the archaeological excavations of Herculaneum, ~ 7 km west of the Somma -Vesuvius crater, allowed reconstruction of the Late Quaternary palaeoenvironmental evolution of the site. The data provide clear evidence for ground uplift movements involving the studied area. The Holocenic sedimentary sequence on which the archaeological remains of Herculaneum rest has risen several meters at an average rate of ~ 4 mm/yr. The uplift has involved the western apron of the volcano and the Sebeto-Volla Plain, a populous area including the eastern suburbs of Naples. This is consistent with earlier evidence for similar uplift for the areas of Pompeii and Sarno valley (SE of the volcano) and the Somma -Vesuvius eastern apron. An axisimmetric deep source of strain is considered responsible for the long-term uplift affecting the whole Somma -Vesuvius edifice. The deformation pattern can be modeled as a single pressure source, sited in the lower crust and surrounded by a shell of Maxwell viscoelastic medium, which experienced a pressure pulse that began at the Last Glacial Maximum.

  7. Compliance of Michigan dentists with radiographic safety recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Nakfoor, C.A.; Brooks, S.L. (University of Michigan School of Dentistry, Ann Arbor (United States))


    We surveyed a random sample of 398 Michigan dentists in private practice to determine their compliance with the American Dental Association Council's recommendations for radiographic equipment and techniques. The response rate was 67% of the questionnaires delivered successfully. The majority of dentists use only D-speed film (73%) and round collimation of the x-ray beam (90%). Only 5% have an x-ray machine equipped with a rectangular collimator and 18% have at least one machine with a pointed cone. Leaded apron use is almost universal, but only 49% of the dentists use cervical collars in addition to the apron. The majority of dentists surveyed do not comply with the American Dental Association Council's recommendations on film speed, collimation, and use of leaded cervical collar. Using effective dose equivalents determined by Gibbs et al. for a variety of radiographic techniques, we estimate that an eight-fold reduction in radiation dose could be achieved without eliminating a single radiograph if all dentists used E-speed film and collimation of the beam to the size of the film.

  8. Distribution and habitat utilization of the gopher tortoise tick (Amblyomma tuberculatum) in southern Mississippi (United States)

    Ennen, Joshua R.; Qualls, Carl P.


    The distribution of the gopher tortoise tick (Amblyomma tuberculatum) has been considered intrinsically linked to the distribution of its primary host, gopher tortoises (Gopherus polyphemus). However, the presence of G. polyphemus does not always equate to the presence of A. tuberculatum. There is a paucity of data on the ecology, habitat preferences, and distribution of A. tuberculatum. The goals of this study were to assess the distribution of A. tuberculatum in southern Mississippi and to determine which, if any, habitat parameters explain the distribution pattern of A. tuberculatum. During 2006-2007, we examined 13 G. polyphemus populations in southern Mississippi for the presence of A. tuberculatum, and we measured a suite of habitat parameters at each site. Only 23% of the G. polyphemus populations supported A. tuberculatum, suggesting a more restricted distribution than its host. The results of our multivariate analyses identified several habitat variables, e.g., depth of sand and percentage of sand in the topsoil and burrow apron, as being important in discriminating between sites with, and without, A. tuberculatum. Amblyomma tuberculatum was only found at sites with a mean sand depth of >100 cm and a mean percentage of topsoil and burrow apron sand composition >94.0 and 92.4, respectively. Thus, environmental factors, and not just its host's range, seem to influence the distribution of A. tuberculatum.

  9. Scatter radiation breast exposure during head CT: impact of scanning conditions and anthropometric parameters on shielded and unshielded breast dose

    Energy Technology Data Exchange (ETDEWEB)

    Klasic, B. [Hospital for pulmonary diseases, Zagreb (Croatia); Knezevic, Z.; Vekic, B. [Rudjer Boskovic Institute, Zagreb (Croatia); Brnic, Z.; Novacic, K. [Merkur Univ. Hospital, Zagreb (Croatia)


    Constantly increasing clinical requests for CT scanning of the head on our facility continue to raise concern regarding radiation exposure of patients, especially radiosensitive tissues positioned close to the scanning plane. The aim of our prospective study was to estimate scatter radiation doses to the breast from routine head CT scans, both with and without use of lead shielding, and to establish influence of various technical and anthropometric factors on doses using statistical data analysis. In 85 patient referred to head CT for objective medical reasons, one breast was covered with lead apron during CT scanning. Radiation doses were measured at skin of both breasts and over the apron simultaneously, by the use of thermo luminescent dosimeters. The doses showed a mean reduction by 37% due to lead shielding. After we statistically analyzed our data, we observed significant correlation between under-the-shield dose and values of technical parameters. We used multiple linear regression model to describe the relationships of doses to unshielded and shielded breast respectively, with anthropometric and technical factors. Our study proved lead shielding of the breast to be effective, easy to use and leading to a significant reduction in scatter dose. (author)

  10. Efficacy of breast shielding during CT of the head

    Energy Technology Data Exchange (ETDEWEB)

    Brnic, Z.; Hebrang, A.; Anic, P. [Department of Diagnostic and Interventional Radiology, University Hospital Merkur, Zajceva 19, 10000, Zagreb (Croatia); Vekic, B. [' ' Ruder Boskovic' ' Research Institute, 10000, Zagreb (Croatia)


    In light of increasing frequency of CT examinations in the past decades, the aims of this prospective study were to investigate scatter radiation breast exposure in head CT and its dependence upon body constitution, and to assess the efficacy of lead shielding as a means of breast dose reduction. In 49 women referred to head CT for objective medical reasons one breast was covered with lead apron during CT scanning. Radiation doses were measured by use of thermoluminescent dosimeters, at skin of both breasts and over the apron. The doses were then compared as well as correlated to body mass index and meatus acusticus externus-to-dosimeter distance, respectively. Average exposure at the skin of the unshielded breast was 0.28 mGy (range 0.15-0.41 mGy), compared with 0.13 mGy (range 0.05-0.29 mGy) at the shielded breast. The doses showed a mean reduction by 57% due to lead shielding. At least half of breast exposure was imparted to the breast from outside, whereas the remainder results from internal scatter. The higher the body mass index, the higher the percentage of internal scatter in total breast dose. Although the level of scatter radiation to the breast is generally low during head CT examination, the use of lead cover enables recognizable further reduction of the exposure, and is recommended as a feasible and effective procedure of breast protection during CT of the head. (orig.)

  11. Bacteriological Monitoring of Radiology Room Apparatus in the Department of Radiological Technology and Contamination on Hands of Radiological Technologists

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Chil [Dept. of Radiologic Technology, Daegu Health College, Daegu (Korea, Republic of)


    Distribution of microorganisms were examined for the bucky tables in the radiology rooms of the department of radiological technology, the aprons, handles of various apparatus, handles of mobile radiological apparatus, and hands of the radiological technologists. As a result, relatively larger amounts of bacteria were found on the handles of the mobile radiological apparatus and the aprons. Among the isolated bacteria, Acinetobacter baumanni (7.3%), Klebsiella pneumoniae (6.7%), Staphylococcus aureus (3.9%), Serratia liquefaciens (1.7%), Enterobacter cloaceae (0.6%), Providenica rettgeri (0.6%) are known as the cause of nosocomial infection (hospital acquired infection). In addition, similar colonies were also found on the hands of the radiological technologists such as microorganisms of Klebsiella pneumoniae (8.4%), Staphylococcus aureus (6.6%), Yersinia enterocolotica (5.4%), Acinetobacter baumanni (4.2%), Enterobacter cloaceae (2.4%), Serratia liquefaciens (1.8%), Yersinia pseuotuberculosis (18%), Enterobacter sakazakii (1.2%), and Escherichia coli (0.6%). In particular, this result indicates clinical significance since Staphylococcus aureus and Escherichia coli show strong pathogenicity. Therefore, a continuous education is essential for the radiological technologists to prevent the nosocomial infection.

  12. Ground improvement for cruise ship terminal expansion project at Canada Place, Vancouver, BC

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D. [Thurber Engineering Ltd., Vancouver, BC (Canada)


    Expansion of the cruise ship terminal at the offshore end of Canada Place is described, with particular emphasis on soil conditions which influenced foundation design for the 10,000 sq m pile-supported deck and the associated ground improvement measures required to assure public health and safety. To provide the required ground improvements, vibro-densification of the existing granular fill and self-feeding of gravel into the silt unit were utilized offshore of the existing apron. The objective here was to make the loose granular fill denser in order to make it non-liquefiable and to strengthen or stiffen the underlying silt unit to minimize earthquake-induced displacements. Under the apron surrounding the existing structure, 145 seismic drains were installed into the granular fill to a depth of 13 m. The purpose of these seismic drains is to prevent liquefaction. The expanded terminal facility will provide additional cruise ship berthing and visitor facilities on a pile-supported deck structure.

  13. 心血管介入手术辐射防护设施与措施防护效果的监测与评价%The monitoring and evaluation of protection effect of radiation protective facility and measure in cardiovascular interventional procedures

    Institute of Scientific and Technical Information of China (English)

    张继勉; 丁艳秋; 张文艺; 焦玲; 张晓东; 张良安


    Objective: To monitor and analyze the protection effect of protective appliance to operators in Cardiovascular Interventional Procedures and to provide a basis data for radiation protection of operators. Methods:TLD dosimeters were used to measure the protection effect of lead rubber apron of the first operator, the second operator and nurse in cardiovascular interventional procedures. The protection effect of lead screen and lead curtain also was measured. Results:The dose of outer lead rubber apron was obviously higher than inner. The attenuation ratio of lead rubber apron for the first operator was 91.1%;the attenuation ratio of lead rubber apron for the second operator was 88.6%;the shielding efficiency of lead rubber apron was obvious. The attenuation ratio of lead screen on the treatment couch was 96.0%. The attenuation ratio of lead curtain beside the treatment couch was 97.0%. Conclusion:The radiation protective facility and measure was effective in Cardiovascular Interventional Procedures.%目的:对心血管介入手术中操作者辐射剂量控制措施与设施防护效果进行监测与评价,获取对心血管介入手术辐射防护设计有意义的数据。方法:将热释光剂量计(TLD)元件分别放置于第一术者、第二术者和护理人员的铅衣内侧以及铅衣外侧,对铅衣屏蔽效果进行测量;通过在诊疗床上铅屏内侧以及外侧、床侧铅帘内侧以及外侧放置TLD元件,对其诊疗床铅屏、铅帘的防护效果进行测量。结果:第一术者与第二术者胸部铅衣外侧的剂量大于内侧,说明铅衣发挥了屏蔽散射X射线的作用。第一术者铅衣对射线的衰减率为91.1%,第二术者为88.6%。固定防护设施床上铅屏对射线的衰减率为96.0%,床侧铅帘对射线的衰减率为97.0%。结论:心血管介入手术现场的辐射防护措施与设施是有效的。

  14. Risk of whole body radiation exposure and protective measures in fluoroscopically guided interventional techniques: a prospective evaluation

    Directory of Open Access Journals (Sweden)

    Rivera Jose


    Full Text Available Abstract Background Fluoroscopic guidance is frequently utilized in interventional pain management. The major purpose of fluoroscopy is correct needle placement to ensure target specificity and accurate delivery of the injectate. Radiation exposure may be associated with risks to physician, patient and personnel. While there have been many studies evaluating the risk of radiation exposure and techniques to reduce this risk in the upper part of the body, the literature is scant in evaluating the risk of radiation exposure in the lower part of the body. Methods Radiation exposure risk to the physician was evaluated in 1156 patients undergoing interventional procedures under fluoroscopy by 3 physicians. Monitoring of scattered radiation exposure in the upper and lower body, inside and outside the lead apron was carried out. Results The average exposure per procedure was 12.0 ± 9.8 seconds, 9.0 ± 0.37 seconds, and 7.5 ± 1.27 seconds in Groups I, II, and III respectively. Scatter radiation exposure ranged from a low of 3.7 ± 0.29 seconds for caudal/interlaminar epidurals to 61.0 ± 9.0 seconds for discography. Inside the apron, over the thyroid collar on the neck, the scatter radiation exposure was 68 mREM in Group I consisting of 201 patients who had a total of 330 procedures with an average of 0.2060 mREM per procedure and 25 mREM in Group II consisting of 446 patients who had a total of 662 procedures with average of 0.0378 mREM per procedure. The scatter radiation exposure was 0 mREM in Group III consisting of 509 patients who had a total 827 procedures. Increased levels of exposures were observed in Groups I and II compared to Group III, and Group I compared to Group II. Groin exposure showed 0 mREM exposure in Groups I and II and 15 mREM in Group III. Scatter radiation exposure for groin outside the apron in Group I was 1260 mREM and per procedure was 3.8182 mREM. In Group II the scatter radiation exposure was 400 mREM and with 0.6042 m

  15. Organ doses of the cardiologists and their assistants during interventional cardiology procedures at teaching general hospitals in Mashhad/ Iran

    Energy Technology Data Exchange (ETDEWEB)

    Bahreyni Toosi, M.; Zare, H.; Bayani, Sh.; Esmaili, S. [Mashhad University of Medical Sciences, Medical Physics Dep., Faculty of Medicine, Mashhad (Iran, Islamic Republic of)


    Full text of publication follows: Protection of medical personnel in interventional cardiology is now days one of the most important issues of radiological protection. Due to the rapid increase of coronary heart disease in developed and developing countries, application of interventional techniques such as coronary angiography and angioplasty have also increased sharply over past two decades. While these procedures are carried out cardiologists and their assistants are remained close to the patient and within the hot area of the radiation field. Therefore they are subject to receive significant doses of radiation. In this study doses received by critical and more vulnerable organs of cardiologists and their assistants were measured by thermoluminescent dosimeters (T.L.D.). T.L.D. measurements were carried for 115 coronary angiography (C.A.) and 30 pre-cutaneous transluminal coronary angioplasty (P.T.C.A.) procedures at teaching general hospitals in Mashhad-Iran. Doses received by thyroid, gonad, right and left hands of the study groups were measured. For this purpose T.L.D. were placed on and underneath of the lead apron adjacent to gonads and on the wrist of both hands. The results of this study imply that: a) For both groups left hands are subject to receiving the highest mean dose (0.18 mGy/P.T.C.A.) b) Thyroid mean dose per P.T.C.A. received by the T.L.D. chips on the shield is 0.72 mGy and is much higher than corresponding value for the T.L.D. placed underneath the shield. c) Gonads would receive the highest mean dose per P.T.C.A. (0.16 mGy), second to left hand, if lead apron is not worn, but lead apron reduces the dose by a factor of nearly six. d) General speaking assistants, mostly stood on the right side of cardiologists, receive smaller dose. e) P.T.C.A. induces a higher dose to all organs of both cardiologists and their assistants when compared with the corresponding doses arising from C.A. procedure. (authors)

  16. Triassic deep-marine sedimentation in the western Qinling and Songpan terrane

    Institute of Scientific and Technical Information of China (English)


    Triassic sequences in both the western Qinling and Songpan terrane are composed mostly of deep-marine sediments. A detailed study was carried out on main sedimentary facies of Triassic successions, showing that they resulted from diverse sedimentary processes, such as submarine debris-flows, turbidity currents, bottom-flows, suspension fallout, and fluidized sediment flows. Debris-flows are dividable into two types, gravelly and sandy debris-flows, respectively, and the sandy debris-flow deposits make up considerable portion of the Triassic successions concerned. Turbidite is characterized by occurrence of normal grading, and the whole Bouma sequences, though widely developed, are not totally attributed to true turbidity currents. The non-graded Ta division is thought to originate from sandy debris flows, whereas the rest divisions result from low-density currents or from bottom-current modification if they contain sedimentary structures related to traction currents. Four types of facies associations are distinguished within Triassic deep-marine successions: massive and thick-bedded coarse-grained facies association, medium- and thick-bedded sandstone with interlayered fine-grained facies association, interlayered thin-bedded fine-grained facies association, and syn-sedimentary slump/breccia facies association. Spatial distribution of the different facies associations suggests that Lower Triassic sedimentation occurred primarily in continental slope, submarine channels, and base-of-slope aprons in the Hezuo-Jianzha region of the western Qinling, whereas the Middle Triassic consists mainly of sedimentary facies of base-of-slope aprons and submarine incised valleys. The counterparts in the Dangchang-Diebu region, in contrast, are characterized by platform carbonates. The shallow-marine carbonates evolved into deep-marine facies since the Ladinian, indicative of rapid drowning of the Carnian carbonate platform in Middle Triassic times. Depositional history of Lower

  17. Depositional architecture and evolution of the Late Miocene slope channel-fan-system in the northeastern shelf-margin of South China Sea (United States)

    Jiang, Jing; Lin, Changsong; Zhang, Zhongtao; Tian, Hongxun; Tao, Ze; Liu, Hanyao


    The Upper Miocene in the Pearl River Mouth Basin of northwestern shelf-margin of South China Sea Basin contains a series of slope channel - fan systems. Their depositional architecture and evolution are documented in this investigation based on an integrated analysis of cores, logs, and seismic data. Four depositional-palaeogeomorphological elements have been identified in the slope channel-fan systems as follows: broad, shallow and unconfined or partly confined outer-shelf to shelf-break channels; deeply incised and confined unidirectionally migrating slope channels; broad or U-shaped, unconfined erosional-depositional channels; frontal splays-lobes and nonchannelized sheets. The slope channels are mostly oriented NW-SE, which migrated unidirectionally northeastwards and intensively eroded almost the whole shelf-slope zone. The channel infillings are mainly mudstones, interbedded with siltstones. They might be formed by gravity flow erosion as bypassing channels. They were filled with limited gravity flow sediments at the base and mostly filled with lateral accretionary packages of bottom current deposits. At the end of the channels, a series of small-scale slope fans developed and coalesced into fan aprons along the base of the slope. The unconfined erosional-depositional channels at the upper parts of the fan-apron-systems display compound infill patterns, and commonly have concave erosional bases and convex tops. The frontal splays-lobes representing middle to distal deposits of fan-apron-systems have flat-mounded or gull-wing geometries, and the internal architectures include bidirectional downlap, progradation, and chaotic infillings. The distal nonchannelized turbidite sheets are characterized by thin-bedded, parallel to sub-parallel sheet-like geometries. Three major unconformities or obvious erosional surfaces in the channel-fan systems of the Upper Miocene are recognized, and indicate the falling of sea-level. The depositional architecture of sequences

  18. Understanding Gully Formation and Seasonal Flows on Recent and Current Mars (United States)

    Gulick, Virginia C.; Glines, Natalie


    The discoveries of gullies and seasonal slope flows (RSL) have re-ignited the debate over various channel, valley, and gully formation mechanisms on Mars. The controversy over whether liquid water was involved with gully formation, harkens back to the mid-1970s to early 2000s, where catastrophic flooding, surface runnoff and ground-water sapping processes were strongly debated along with other mechanisms as the primary processes responsible for channel and valley formation on Mars. However, over the past decade, the value of multiple working hypotheses has again become apparent, this time in understanding the formation of Martian gullies and Recurring Slope Lineae. Various mechanisms put forth to explain these landforms include liquid H2O/ice erosion, CO2 ice/frost sublimation, CO2 ice block sliding, water and brine flows, salt deliquescence, and dry granular flows, among others.We carried out detailed morphologic/morphometric studies of gullies in various environmental settings on Mars to evaluate the potential formation processes. Using HiRISE images and DTMs, we mapped and generated detailed longitudinal and cross-sectional profiles of gully systems and estimated volumes for both the gullies and their debris aprons. Several gullies form highly integrated patterns similar to fluvial systems. Additionally, RSL are often found either in the tributaries of these integrated systems or in adjacent regions, implying that RSL may play a role in initiating gully formation or mark the last vestiges of water activity in these locations. We also find that the more highly integrated gullies have volumes significantly larger than their aprons, suggesting that the missing volumes (~40-60% or more) were likely the volatiles involved in gully formation. Additionally, THEMIS and TES surface temperatures of these integrated gully sites, many of which also contain RSL, are at or above freezing seasonally suggesting that the volatile component may be consistent with H2O although CO2

  19. Geometry of the proximal part of the modern turbidite depositional system of the Carapebus Formation, Campos Basin: a model for reservoir heterogeneities; Geometria da porcao proximal do sistema deposicional turbiditico moderno da Formacao Carapebus, Bacia de Campos; modelo para heterogeneidades de reservatorio

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Luis Claudio Ribeiro; Kowsmann, Renato Oscar; Almeida Junior, Waldemar de; Murakami, Celso Yoshihito; Schreiner, Simone; Miller, Dennis James; Piauilino, Pedro Orlando Vasconcelos [PETROBRAS, Rio de Janeiro, RJ (Brazil). Exploracao e Producao. Unidade de Servico Submarino]. E-mail:


    The deep-water marine sedimentary environment of the Cenozoic of the Campos Basin is examined at the modern sea floor, where it can be better understood. This environment is responsible for the genesis of the turbidite systems of the Carapebus Formation, the reservoirs that hold more than 90% of Brazil's petroleum reserves. The study was developed with the records of regional side-scan sonar, swath bathymetry, sub-bottom profiler data, standard multichannel 3D seismic surveys and piston cores covering almost the entire basin. After leaving the Almirante Camara Canyon, the turbiditic flows erode the muddy debris apron surrounding the continental slope and begin to deposit thick layers of clean sand into a big trough in water depths of 1800 m to 3000 m. The trough is 3.5 km wide, 150 m deep, 150 km long, and is formed by a chain of salt withdrawal mini-basins. In some places the sea floor is flat enough to develop today a depositional lobe, in all aspects analogous to the best, geologically ancient petroleum reservoirs in the basin. Aspects of the system: 1) the arcosean sands are brought by the river, cross the shelf, the incised valley, the canyon, and deposit as turbidites - they do not originate from a collapse of the continental slope; 2) a wide muddy debris apron surrounds the continental slope (slope apron), and represents a huge volume of sediment in the Campos Basin ; 3) the turbidites do not develop a submarine fan, but are deposited in an elongated trough formed by salt tectonics; 4) the turbidite beds, both in the lobe or in the trough, are not deposited during a single episode, but in multiple events over significant geologic time in which small channels which brought the turbidites avulse and meander along the entire depositional area, building a single amalgamated bed; 5) classic channel-levees are not present because this system comprises a sandy braid plain and the levees are as sandy as the channel; 6) a hierarchical depositional model for bulb


    Directory of Open Access Journals (Sweden)

    Antônio Carlos de Barros Corrêa


    Full Text Available The assessment of the geomorphological dynamics of ecologically discontinuous areas in the elevated compartments of Borborema Highlands has prioritized the occurrence of datable sedimentary deposits, which have been identified following a qualitative surveying of geomorphological features. The chosen pilot-areas for the conduction of this research were the Baixa Verde massif and the highlands of Brejo da Madre de Deus, State of Pernambuco. Among the several identified features, hill slope deposits, colluvium, in the shape of ramps and aprons were chosen for reconstructing the geomorphological dynamics. The stratigraphy of materials that overlie the surface of the landscape was defined following the elaboration of log sections. Optically stimulated luminescence dating of sediments was used as a tool for the qualitative reconstruction of depositional events and establishing models for landforms evolution. The obtained results indicated the occurrence of discrete events of material remobilization along the slopes as a response to climatic oscillations following the last glacial maximum.

  1. Hydrogen propulsion systems for transit buses - results of operation in passenger transport

    Energy Technology Data Exchange (ETDEWEB)

    Hipp, E.; Gruber, C. [MAN Nutzfahrzeuge AG, Advance Development (Germany)


    Hydrogen is a source of energy which can in the long term play a major role in the energy and transport industries. It can be generated without using fossil products and against the background of ever shorter oil reserves it reduces the supply risks for transport and industry. Further advantages of hydrogen as a fuel for motor vehicles are its potential for reduction of greenhouse gases and pollutants from traffic. The hydrogen project at Munich airport aims to demonstrate the technical feasibility of autonomous hydrogen generation combined with operation of vehicles. MAN is participating in this project with two low-floor articulated buses with hydrogen engines. A further vehicles from Neoplan has also been fitted with MAN H{sub 2} driveline technology. The vehicles will be used for carrying passengers on the airport apron from early 1999 to the end of 2000 and are expected to supply important information on the use of hydrogen in day-to-day transport. (orig.)

  2. 宫山咀水库除险加固研究%Research on risk removal and reinforcement of Gongshanzui Reservoir

    Institute of Scientific and Technical Information of China (English)



    Risk removal and reinforcement design research is carried out at reservoir dam upstream and downstream slope protection,spillway apron concrete,spillway downstream stilling basin,retaining walls on both sides of spillway,water conveying tunnel etc.through analysis on diseases of Gongshanzui Reservoir.%通过对宫山咀水库存在的病险进行分析,对水库大坝上下游护坡、溢洪道护坦混凝土、溢洪道下游消力池、溢洪道两侧挡墙、输水洞等进行了除险加固设计研究。

  3. Paleoceanographic events in cretaceous petroleum basins, offshore mid-Norway of SE Saskatchewan, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Gradstein, F.M.; Saether, T.; Nystuen, J.P.; Backstrom, S.A. [Saga Petroleum A/S, Forus (Norway)


    During the Cretaceous period, the narrow, longitudinal seaways between Greenland and Norway received a large volume of fine-grained siliciclast sediments with intercalated gravity-flow sandstone wedges. The sedimentary succession may be subdivided into four broad units: (1) thin and mostly oxic, marly sediments, (2) dark, dysaerobic mudstones and minor sands, (3) thick mudstone facies with thin slope-apron turbidite sands, and (4) grayish laminated mudstones with local sands in the northern area. A widespread Barremian-Aptian hiatus may be linked to Atlantic rift-onset unconformities recognized offshore eastern Canada. Around the lower-upper Cretaceous boundary, watermass conditions changed from dysaerobic to oxic, an event also reported from central and western Europe.

  4. Microbial lifestyles that enable survival in lithifying habitats

    DEFF Research Database (Denmark)

    Tamez-Hidalgo, Paulina


    The precipitation of carbonates in the travertine forming Narrow Gauge hot spring in Yellowstone National Park occurs at a rapid rate, whereby microorganisms that colonize the ponds and apron facies are required to overcome lithification. CO2-fixation by autotrophic microorganisms in this cation......-rich environment further promotes carbonate encapsulation. Microorganisms that alter their micro-habitat through dissimilative metabolic processes such as H2S and NH4+oxidation, can decrease acid neutralizing capacity (ANCcarb = [HCO3-] + 2[CO32-] + [OH-] - [H+] ) and locally delay CaCO3 mineralization. Genomic...... the microbially mediated reactions of the sulfur cycle might change the conditions in the local microhabitat, this does not alter the overall mass of geochemical carbonate precipitation. The metabolic products might aid autotrophic microorganisms in colonizing and surviving, however, for some time in a strongly...


    Ramaroson, R.


    Richard Ramaroson1,4, Klaus Schaefer2, Stefan Emeis2, Carsten Jahn2, Gregor Schürmann2, Maria Hoffmann2, Mikhael Zatevakhin3, Alexandre Ignatyev3. 1ONERA, Châtillon, France; 4SEAS, Harvard University, Cambridge, USA; 2FZK, Garmisch, Germany; (3)FSUE SPbAEP, St Petersburg, Russia. 2-month field campaigns have been organized at CDG airports in autumn 2004 and summer 2005. Air quality and ground air traffic emissions have been monitored continuously at terminals and taxi-runways, along with meteorological parameters onboard trucks and with a SODAR. This paper analyses the commercial engine emissions characteristics at airports and their effects on gas pollutants and airborne particles coupled to meteorology. LES model results for PM dispersion coupled to microphysics in the PBL are compared to measurements. Winds and temperature at the surface and their vertical profiles have been stored with turbulence. SODAR observations show the time-development of the mixing layer depth and turbulent mixing in summer up to 800m. Active low level jets and their regional extent have been observed and analyzed. PM number and mass size distribution, morphology and chemical contents are investigated. Formation of new ultra fine volatile (UFV) particles in the ambient plume downstream of running engines is observed. Soot particles are mostly observed at significant level at high power thrusts at take-off (TO) and on touch-down whereas at lower thrusts at taxi and aprons ultra the UFV PM emissions become higher. Ambient airborne PM1/2.5 is closely correlated to air traffic volume and shows a maximum beside runways. PM number distribution at airports is composed mainly by volatile UF PM abundant at apron. Ambient PM mass in autumn is higher than in summer. The expected differences between TO and taxi emissions are confirmed for NO, NO2, speciated VOC and CO. NO/NO2 emissions are larger at runways due to higher power. Reactive VOC and CO are more produced at low powers during idling at

  6. Occupational Exposure to Ultrafine Particles among Airport Employees - Combining Personal Monitoring and Global Positioning System

    DEFF Research Database (Denmark)

    Møller, Karina Lauenborg; Thygesen, Lau Caspar; Schipperijn, Jasper


    BACKGROUND: Exposure to ultrafine particles (UFP) has been linked to cardiovascular and lung diseases. Combustion of jet fuel and diesel powered handling equipment emit UFP resulting in potentially high exposure levels among employees working at airports. High levels of UFP have been reported...... at several airports, especially on the apron, but knowledge on individual exposure profiles among different occupational groups working at an airport is lacking. PURPOSE: The aim of this study was to compare personal exposure to UFP among five different occupational groups working at Copenhagen Airport (CPH...... concentrations (GM: 12 to 20×103 UFP/cm3). CONCLUSION: The study demonstrates a strong gradient of exposure to UFP in ambient air across occupational groups of airport employees....

  7. 大众传媒大厦直升机停机坪建设小结%The Mass Media Building Helipad Construction Summary

    Institute of Scientific and Technical Information of China (English)



    本文介绍了超高层建筑建设直升机停机坪的必要性,设计与施工内容,施工中需注意事项。举例说明在超高层建筑消防抢险救灾中,直升机救援的重要性,希望引起有关部门对超高层建筑建设停机坪的重视。%This paper introduces the necessity of high-rise bu-ilding helipad construction, design and construction content, mat ers in construction should pay at ention to. It il ustrates in the fire rescue and disaster relief of the high-rise building, the importance of the rescue helicopter, hopes the relevant depar-tments should pay at ention to the construction of high-rise bu-ilding apron.

  8. Evaluating the usability of a commercial cooling vest in the Hong Kong industries. (United States)

    Chan, Albert P; Yang, Yang; Song, Wen-Fang


    Purpose -The provision of appropriate personal cooling vests is recognized as an effective measure to combat heat stress. However, personal cooling vests are not widely implemented in the Hong Kong industries. The current study aims to evaluate the usability of a hybrid cooling vest that is associated with the success of its application in industrial settings. Materials and methods - A self-administrated questionnaire focusing on 10 subjective attributes of cooling effect, ergonomic design, and usability of a hybrid cooling vest was administered with 232 occupational workers in the construction, horticultural and cleaning, airport apron services and kitchen and catering industries. Results - A structural equation model estimated by analysis of moment structures was constructed to evaluate the usability of the cooling vest, as influenced by cooling effect and ergonomic design. Results showed that cooling effect (path coefficient = 0.69, p ergonomic design (path coefficient = 0.55, p ergonomic design for occupational workers.

  9. A Smart Mathematic Morphology Method for Recognition and Understanding of Airfield

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-cheng; TIAN Yan; TIAN Jin-wen; LIU Jian; LIANG Chao-sheng; TAO Wen-bin


    A method used for recognition and understanding of airfield based on mathematical morphology is proposed in this paper. The new approach can be divided into three steps. First, to extract the typical geometric structure features of airfield, a segmentation method called recursive Otsu algorithm is employed on an airfield image. Second, thinning and shrinking algorithms are utilized to obtain the contour of airfield with single pixel and to remove diffused small particles. Finally, Radon transform is adopted to extract two typical and important components, primary and secondary runways of airfield exactly. At the same time, region growing algorithm is exploited to get the other components such as parking apron and garages. The experimental results demonstrate that the proposed method gives good performance.

  10. Sutter Buttes-the lone volcano in California's Great Valley (United States)

    Hausback, Brain P.; Muffler, L.J. Patrick; Clynne, Michael A.


    The volcanic spires of the Sutter Buttes tower 2,000 feet above the farms and fields of California's Great Valley, just 50 miles north-northwest of Sacramento and 11 miles northwest of Yuba City. The only volcano within the valley, the Buttes consist of a central core of volcanic domes surrounded by a large apron of fragmental volcanic debris. Eruptions at the Sutter Buttes occurred in early Pleistocene time, 1.6 to 1.4 million years ago. The Sutter Buttes are not part of the Cascade Range of volcanoes to the north, but instead are related to the volcanoes in the Coast Ranges to the west in the vicinity of Clear Lake, Napa Valley, and Sonoma Valley.

  11. Nano particles as the primary cause for long-term sunlight suppression at high southern latitudes following the Chicxulub impact - evidence from ejecta deposits in Belize and Mexico

    DEFF Research Database (Denmark)

    Vajda, Vivi; Ocampo, Adriana; Ferrow, Embaie;


    Life on Earth was sharply disrupted 66 Ma ago as an asteroid hit the sea-floor in what is today Yucatan Peninsula, Mexico. Approximately 600 km3 of sedimentary rock were vapourized, ejected into the atmosphere and subsequently deposited globally as an ejecta apron and fallout layer. Proximal ejecta...... deposits occur in Belize and southern Mexico where the so called Albion island spheroid bed is superimposed on the target rock (the Barton Creek Formation). We analysed the spheroid bed via Mössbauer spectroscopy, petrology, XRD, and palynology at several sites ~ 350-500 km distance from the crater centre....... Our results show that the relative concentrations of Fe in nano-phase goethite (α-FeOOH) are very high in the spheroid bed samples from Albion Island (Belize) and from Ramonal South (Mexico), but are low to absent in the spheroid bed at Ramonal North, and in the Cretaceous target rock. Moreover, our...

  12. A classification of martian gullies from HiRISE imagery (United States)

    Auld, Katherine S.; Dixon, John C.


    Due to the large and varied population of gullies observed in Mars High Resolution Imaging Science Experiment (HiRISE) imagery that exhibit diverse characteristics, this paper develops a classification of martian gullies based on their morphological characteristics. This provides a firmer foundation for future investigation of the genesis of different gully morphologies. The Mars Reconnaissance Orbiter (MRO) image catalog on the HiRISE website was examined and 869 images, chosen from the first 25,000 orbits, show a wide variety of gully morphologies. The images were analyzed using ENVI 4.4 and ENVI Zoom and the gullies were cataloged and divided into groups based on the presence and character of the dominant morphological components of alcove, channel, and apron associated with each gully. 7519 gullies were identified in the images and the length and width of the components were measured in ENVI to facilitate classification. Seven classes were developed based on morphology.

  13. Lahar hazards at Agua volcano, Guatemala (United States)

    Schilling, S.P.; Vallance, J.W.; Matías, O.; Howell, M.M.


    At 3760 m, Agua volcano towers more than 3500 m above the Pacific coastal plain to the south and 2000 m above the Guatemalan highlands to the north. The volcano is within 5 to 10 kilometers (km) of Antigua, Guatemala and several other large towns situated on its northern apron. These towns have a combined population of nearly 100,000. It is within about 20 km of Escuintla (population, ca. 100,000) to the south. Though the volcano has not been active in historical time, or about the last 500 years, it has the potential to produce debris flows (watery flows of mud, rock, and debris—also known as lahars when they occur on a volcano) that could inundate these nearby populated areas.

  14. Accesorios metálicos de correas de cinturones militares altoimperiales hallados en Hispania

    Directory of Open Access Journals (Sweden)

    Aurrecoechea Fernández, Joaquín


    Full Text Available Study of roman military «aprons» found in Hispania, specially the specimens discovered in a tomb in Aznalcázar (prov. of Seville. This group is of special relevance due to the fact that there are very few pieces of this kind in funerary contexts.Estudio sobre los accesorios metálicos pertenecientes a «mandiles» militares de época romana hallados en Hispania. Entre ellos se documenta un conjunto completo aparecido en una tumba de Aznalcázar (Sevilla, hallazgo de excepcional importancia debido a la escasez de piezas semejantes en contextos sepulcrales. Finalmente, se interpreta el significado de estos bronces dentro del marco cronológico de la dinastía flavia.

  15. Determination of effective dose for workers hemodynamics service using double dosimetry; Determinacion de la dosis efectiva para los trabajadores del servicio de hemodinamica usando doble dosimetria

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Lopez, M. A.; Lobato Munoz, M.; Jodar Lopez, C. A.; Ramirez Ros, J. C.; Jerez Sainz, M. I.; Pamos Urena, M.; Carrasco Rodriguez, J. L.


    The use of an additional dosimeter at the level of the neck above the lead apron we can provide an indication of the dose in the head (the Crystal dose). In addition, it is possible to combine the two readings of the dosimeter to provide an improved estimate of the effective dose. In the hemodynamics service of our Hospital we have maintained a worker for 3 years with the double dosimetry read monthly. With the readings from these dosimeters will do following algorithms, several estimates of the effective dose to see if, with working conditions that occur in this service, it would be necessary to extend this practice to the rest of the workers to get a better estimation of effective dose. (Author)

  16. Gullies and Layers in Crater Wall in Newton (United States)


    This dramatic view of gullies emergent from layered outcrops occurs on the wall of a crater within the much larger impact basin, Newton. Newton Crater and its surrounding terrain exhibit many examples of gullies on the walls of craters and troughs. The gullies exhibit meandering channels with fan-shaped aprons of debris located downslope. The gullies are considered to have been formed by erosion--both from a fluid (such as water) running downslope, and by slumping and landsliding processes driven by the force of gravity. This picture was obtained by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in March 2001; it is illuminated from the upper left and covers an area 3 km (1.9 mi) across.

  17. A History of the Danubian Costume in the XIXth Century

    Directory of Open Access Journals (Sweden)

    Cristina Partenie


    Full Text Available Nowadays we attach a great importance to the clothes we wear from the moment we buy or make them, to the moment we decide if they are appropriate with our personal style, the place where we wear them or when we use them. If the XIXth century tries to preserve the tradition with great accuracy the way it was transmitted from generation to generation, in the tumultuous XXth century we attend to the birth of a real industry of fashion. Some reminiscences remain, however, which gives us the opportunity to draw up a study in this regard. The present paper intends to add information regarding the folk costumes in Galati County, especially in the XIXth century. It is a short presentation of some of the most traditional clothes such as: skirt, apron, hood, shirt male and shirt female, decorative designs, footwear; without claiming to have finished the subject we intend to go on with further research.

  18. Seasonal erosion and restoration of Mars' northern polar dunes (United States)

    Hansen, C.J.; Bourke, M.; Bridges, N.T.; Byrne, S.; Colon, C.; Diniega, S.; Dundas, C.; Herkenhoff, K.; McEwen, A.; Mellon, M.; Portyankina, G.; Thomas, N.


    Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO 2 seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.

  19. Survey of radiologic practices among dental practitioners

    Energy Technology Data Exchange (ETDEWEB)

    Goren, A.D.; Sciubba, J.J.; Friedman, R.; Malamud, H. (Long Island Jewish Medical Center, New Hyde Park, NY (USA))


    The purpose of this study was to determine the factors that influence and contribute to patient exposure in radiologic procedures performed in the offices of 132 staff members within the dental department of a teaching hospital. A questionnaire was prepared in which data were requested on brands of film used, type of x-ray unit used, processing, and use of leaded apron, cervical shield, and film holder. Offices were also visited to evaluate performance of existing dental x-ray equipment. Both the Dental Radiographic Normalizing and Monitoring Device and the Dental Quality Control Test Tool were evaluated. The average exposure was equivalent to the class D film (220 mR), but only 13% of those surveyed used the faster class E film, which would reduce patient exposure in half. The survey indicates that dentists are not using the newer low-exposure class E film in their practices.

  20. Thyroid dose distribution in dental radiography

    Energy Technology Data Exchange (ETDEWEB)

    Bristow, R.G.; Wood, R.E.; Clark, G.M. (Ontario Cancer Institute, Toronto (Canada))


    The anatomic position and proven radiosensitivity of the thyroid gland make it an organ of concern in dental radiography. A calibrated thermoluminescent dosimetry system was used to investigate the absorbed dose (microGy) to the thyroid gland resultant from a minimum irradiated volume, intraoral full-mouth radiography technique with the use of rectangular collimation with a lead-backed image receptor, and conventional panoramic radiography performed with front and rear lead aprons. Use of the minimum irradiated volume technique resulted in a significantly decreased absorbed dose over the entire thyroid region ranging from 100% to 350% (p less than 0.05). Because this intraoral technique results in radiographs with greater image quality and also exposes the thyroid gland to less radiation than the panoramic, this technique may be an alternative to the panoramic procedure.

  1. Geology of the Yucca Mountain site area, southwestern Nevada (United States)

    Keefer, W.R.; Whitney, J.W.; Buesch, D.C.


    Yucca Mountain in southwestern Nevada is a prominent, irregularly shaped upland formed by a thick apron of Miocene pyroclastic-flow and fallout tephra deposits, with minor lava flows, that was segmented by through-going, large-displacement normal faults into a series of north-trending, eastwardly tilted structural blocks. The principal volcanic-rock units are the Tiva Canyon and Topopah Spring Tuffs of the Paintbrush Group, which consist of volumetrically large eruptive sequences derived from compositionally distinct magma bodies in the nearby southwestern Nevada volcanic field, and are classic examples of a magmatic zonation characterized by an upper crystal-rich (>10% crystal fragments) member, a more voluminous lower crystal-poor (south

  2. Comparison of Shallow Survey 2012 Multibeam Datasets (United States)

    Ramirez, T. M.


    The purpose of the Shallow Survey common dataset is a comparison of the different technologies utilized for data acquisition in the shallow survey marine environment. The common dataset consists of a series of surveys conducted over a common area of seabed using a variety of systems. It provides equipment manufacturers the opportunity to showcase their latest systems while giving hydrographic researchers and scientists a chance to test their latest algorithms on the dataset so that rigorous comparisons can be made. Five companies collected data for the Common Dataset in the Wellington Harbor area in New Zealand between May 2010 and May 2011; including Kongsberg, Reson, R2Sonic, GeoAcoustics, and Applied Acoustics. The Wellington harbor and surrounding coastal area was selected since it has a number of well-defined features, including the HMNZS South Seas and HMNZS Wellington wrecks, an armored seawall constructed of Tetrapods and Akmons, aquifers, wharves and marinas. The seabed inside the harbor basin is largely fine-grained sediment, with gravel and reefs around the coast. The area outside the harbor on the southern coast is an active environment, with moving sand and exposed reefs. A marine reserve is also in this area. For consistency between datasets, the coastal research vessel R/V Ikatere and crew were used for all surveys conducted for the common dataset. Using Triton's Perspective processing software multibeam datasets collected for the Shallow Survey were processed for detail analysis. Datasets from each sonar manufacturer were processed using the CUBE algorithm developed by the Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). Each dataset was gridded at 0.5 and 1.0 meter resolutions for cross comparison and compliance with International Hydrographic Organization (IHO) requirements. Detailed comparisons were made of equipment specifications (transmit frequency, number of beams, beam width), data density, total uncertainty, and

  3. The Swedish Bohus granite - a stone with a fascinating history (United States)

    Schouenborg, Björn; Eliasson, Thomas


    One of the most well-known and well spread Swedish stone types used as building stones is the Bonus granite. It outcrops in an area north of Gothenburgh (SW Sweden), along the coastline, approximately 35 km wide and 85 km long. The granite continues into Norway as the Iddefjord granite. The Bohus granite is one of Sweden's youngest granites. Isotopic dating shows that the magma cooled at about 920 M years ago and thus marking the end of the Sveconorwegian orogoney. It is a composite granite massif area with several granitic intrusions but with rather homogeneous mineralogy. However, colour and texture varies quite a lot and the colour ranges from red to reddish grey although some pure grey varieties occur sparsely. The grain size ranges from medium grained to coarse grained and even with some porphyric parts. Quarrying in an industrial scale started 1842. The merchant A C Kullgren opened the first quarry and produced stones for the construction of the 86 km long Trollhättan channel connecting lake Vänern and the Atlantic ocean in the SW Sweden The stone was used for constructing harbors and wharves along the channel. Several quarries opened in the late 1800 around 1870 - 1890 and the export increased steadily with deliveries to Germany, Denmark, Holland, England and even to South America. The stone industries in Bohuslän (Bohus county), at its peak in 1929, engaged around 7 000 employees. During the depression in 1930 almost all of them became unemployed. However, as a curiosity, production and export continued to Germany for construction of Germania, the future World capital city ("Welthauptstadt Germania"), planned by Adolf Hitler and Albert Speer. About 500 stone workers were kept employed for this project during the late thirties. Today several varieties are still produced: Evja/Ävja, Tossene, Brastad, Näsinge, Broberg, Nolby, Allemarken and Skarstad. However, the number of stone workers is far from that of the early 1900. The Swedish production is mainly

  4. Physical Modeling of Localized Scour for the Yangtze Estuary Waterway Improvement Project, Phase Ⅰ

    Institute of Scientific and Technical Information of China (English)

    JlA Jianjun; LU Wujiang; QIAN Yadong


    In order to examine the effectiveness of engineering protection against localized scour in front of the south groin-group of the Yangtze Estuary Waterway Improvement Project, Phase Ⅰ , an undistorted physical model on a geometric scale of 1:250 is built in this study, covering two groins and their adacent estuarine areas. By use of rinsing fix-bed model as well as localized mobile-bed model, the experiment is undertaken under bi-directional steady flow. According to the experimental results, waterway dredging leads to the increase in steram velocity, the increase being larger during the ebb than during the flood. Construction of the upstream groin has some influence on the flow patterns near the downstream groin. Localized scour in front of the groin-heads is controlled mainly by ebb flow. In the case of a riverbed composed entirely of silt, the depths of localized scour in front of the two groin-heads are 27 m and 29 m,respectively. In reality, the underneath sediment of the prototype riverbed is clay whose threshold velocity is much higher than the stream velocity in the Yangtze Estuary; therefore, the depths of localized scour will not be much larger than the thickness of the silt layer, i. e. 7.4 m and 4.7 m, respectively. The designed aprons covering the riverbed in fron of the groin-heads are very effective in scour control. Aprons of slightly smaller size can also fulfill the task of protection, but the area of localized scour increases significantly.

  5. Cryoseism Vibrational Movement and Sorting of Detritus of Mars' Regolith Bedforms (E.G., ~ Streaks, Gullies): a New, Dry, Midsummer Antarctic Analogue Mechanism (United States)

    Ford, A. B.


    "SNAP!, CRACK!, POP!" The sounds reverberated across newly shaded permafrost of unusual talus aprons (Ford & Andersen, 1967; J. Geol., 75, 722-732) of interior Antarctica (lats. >84°S; Thiel, Pensacola mtns.), coming from ice cracking under tensile failure (cryoseisms). Apron regoliths show conspicuously reversed downslope particle-size sorting and downslope-oriented lineations (debris-cleared tracts; stone stripes) formed by vibrational movement of detritus by midsummer, diurnal cracking of ice. Moving laterally by vibrations away from cracks, with downslope component by gravity, finer detritus becomes concentrated downslope from coarser debris of initial cliff fall — winnowed, as if on a gigantic vibrating shaking table. Slopes outside shade zones remain free of cracking. Diurnal midday shading of solar-warmed, debris-mantled permafrost- and glacier-surface ice at low ambient midsummer temperatures produces high strain-loading rates that exceed tensile toughness of inhomogeneous, polycrystalline ice containing zones of older but sealed cracks. This dry, mechanical, cryoseism mechanism is here proposed also for now waterless Mars and other icy Solar System bodies. Regolith features of Mars' cryosphere may appear different from anrarctic analogues owing to likely operation over tens if not hundreds of millions of years longer than on Earth. The strain distributions in tensile failure of ice better explain a common spacing uniformity of many martian linear features than others' proposed origins, and for some "active" streaks and gully channels, TARS, RSL and dune-slipface channels, as well as for dune orthogonality, diurnal moonquakes and asteroid-regolith detrital sorting (e.g., "rubble-pile" 25143-Itokawa). Because periodic shade from topography (canyons, craters, etc.) is needed, the mechanism is not expected on flattish terrains where more normal annual cooling rates produce the common polygonal tensile fracturing of ice

  6. Neck incision planning for total laryngectomy: A finite element analysis. (United States)

    Feng, Allen L; Clark, James H; Agrawal, Nishant; Moussa, Walied; Richmon, Jeremy D


    Post-operative complications can be attributed to technical aspects of surgery, yet no studies have investigated the mechanics behind commonly used incisions for total laryngopharyngectomies (TLP). This procedure, seen in head and neck cancer patients, necessitates free tissue transfer to construct a neo-pharynx, creating an inherently greater risk of complications. We sought to investigate the impact of neck incision location on these post-operative complications for TLP using finite element analysis (FEA). A nonlinear hyperelastic 2-D finite element model was used to evaluate the stress and strain along the incision line of two separate neck incision models commonly used for TLP: low-neck apron (LNA) incisions that incorporate the patient׳s tracheostoma and mid-neck apron (MNA) incisions that do not communicate with the tracheostoma. A constant displacement was applied to the incision to simulate normal neck extension experienced during the post-operative phase. Each neck incision was also modeled at varying strain energy densities to simulate various stages of wound healing. For a constant displacement of 40mm, the principal von Mises stress of the LNA incision varied between 5.87 and 6.41MPa, depending on the hyperelastic properties of the healing incision. This stress was concentrated at the junction of the incision and the fixed tracheostomal edge. The MNA model demonstrated a principal von Mises stress that varied between 0.558 and 0.711MPa and was concentrated along the midline of the neck incision. MNA incisions for TL patients result in principal von Mises stresses which are up to 11 times lower than those seen in LNA incisions. These results coincided with clinical observations from a concurrent study that showed a decrease in rate of wound dehiscence for patients undergoing TLP with an MNA incision.

  7. Online software for the estimation of fetal radiation dose to patients and staff members in diagnostic radiology;Sistema online para o calculo de doses fetais de pacientes e trabalhadoras ocupacionalmente expostas em radiologia diagnostica

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Paulo Roberto; Groff, Sybele Guedes de Paulo, E-mail: pcosta@if.usp.b [Universidade de Sao Paulo (DFN/IFUSP), SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear


    An online software, named 'Dose Fetal Web', which calculates the dose of the fetus and the radiological risks from both medical and occupational exposures of pregnant women is described. The software uses a mathematical methodology where coefficients for converting uterus to fetal dose, NUD, have been calculated by using Monte Carlo simulation. In the fetal dose from diagnostic medical examination of the pregnant patient, database information regarding output and other equipment related to parameters from the QA database, maternal and fetal parameters collected by ultrasound procedures were used for the fetal dose estimation. In the case of fetal dose of the pregnant staff member the database information regarding routine individual monitoring dosimetry, such as occupational dose and workload, were used for the estimation. In the first case suppose a 26 weeks pregnant patient had to undergo a single AP abdomen procedure (70 kVp peak tube voltage and total filtration 3mmAl), the fetal dose calculated by the software was 4.61 mGy and the radiological risks would be 5.0{center_dot}10{sup -4} and 0.14 to the probability of mental retardation induction and decline in the IQ score, respectively. In the second case, considering that the staff member can be pregnant, and assuming that she wore a 0,5 mm lead equivalent apron during every interventional radiology procedure and a personal dosimetry reading of 2 mGy{sub TLD}/month measured with the TLDs outside the apron, the fetal dose calculated by the software was 0.02 mSv/month. (author)

  8. Effects of Priming in Combination with Fungicides on Germination and Infestation of Lettuce (Lactuca sativa L.)

    Institute of Scientific and Technical Information of China (English)

    HU Jin; Tylkowska K


    Two seed lots of lettuce (Lactuca sativa L.) cv. Krolowa Majowych were primed in polyethylene glycol (PEG) 8000 at -1.25MPa for 7 days in dark at 20℃. Two fungicide treatments combined with PEG were used to control fungi: 1) Funaben T (0.1%) and Apron 35 SD (0.02%) were added to -1.25 MPa PEG solution (PEG+F); 2) After seed priming and drying,Funaben T was mixed at 5 g kg-1 and Apron 35 SD at 1 g kg-1 of seeds (PEG then F dust). PEG, PEG+F and PEG then F dust treatments reduced significantly thermodormancy and increased the seed germination at 35℃ in both lots. PEG then F dust treatment had the best effect on reducing seed thermodormancy at 35℃, and increased seed germination to 64.5% in lot 1 and 72.0% in lot 2 compared to 0 in untreated. PEG and PEG then F dust treatments have accelerated germination speed at 20 and 15℃ in both lots. There was a significant reduction in seed infestation in which the seeds were treated with PEG+F and PEG then F dust compared to untreated seeds and PEG primed seeds. PEG priming enhanced seed infestation considerably by Alternaria alternata, Penicillium spp., Rhizopus spp. and Ulocladium spp. Mycological analysis showed higher frequency of Alternaria alternata and Ulocladium spp. in untreated seeds at 20℃. Priming in combination with fungicides significantly alleviated the infestation of fungi, especially Alternaria alternata infestation.

  9. Aerodynamic noise numerical simulation and noise reduction of high-speed train bogie section%高速列车转向架部位气动噪声数值模拟及降噪研究

    Institute of Scientific and Technical Information of China (English)

    黄莎; 杨明智; 李志伟; 徐刚


    In order to decrease the aerodynamic noise of train bogie section, three-dimensional, large eddy simulation and FW-H acoustic model were adopted to simulate the aerodynamic noise outside high-speed train bogie section based on Lighthill acoustic theory, and noise reduction advice was proposed. The results show that the aerodynamic noise is a kind of wide frequency noise which exits in wide frequency band without obvious main frequency. The acoustic pressure amplitude of every test point is great at low frequency, decreasing with the increase of frequency, and the acoustic pressure level within 1/3 octave band frequency ranges from 315 Hz to 1 250 Hz. Given a certain incoming wind speed, the total acoustic pressure level is lower when the test point is farther from the noise source. Once aprons are set in bogie sections, acoustic pressure amplitude and total acoustic pressure level of each point reduce compared with that without apron, respectively with an average reduction of about 8% and 1.3 dBA at the speed of 300 km/h. Besides, the average reduction will come to 12% and 2.08 dBA when the apron area increases properly, making noise reduction more effective apparently.%基于Lighthill声学理论,采用三维、LES大涡模拟和FW-H声学模型对高速列车转向架部位气动噪声进行数值模拟,并提出降噪改进意见.研究结果表明:转向架部位气动噪声在很宽的频带内存在,无明显的主频率,是一种宽频噪声;各监测点气动噪声频谱在低频时幅值较大,随着频率的升高,幅值下降,1/3倍频程A声压级主要集中在315~1 250 Hz频率范围内;当来流速度一定时,距离气动噪声源越远,声压级幅值和总声压级越小;在列车转向架部位设置裙板后,运行速度为300 km/h时,车外声压级幅值较无裙板时有所减小,平均降幅约为8%,总声压级平均降幅1.3 dBA;适当增加裙板面积后,声压级幅值平均降幅达到12%,总声压级平均降幅2.08dBA,降噪效果较明显.

  10. Evidence for Recent Liquid Water on Mars: Basic Features of Martian Gullies (United States)


    Water is the chief agent of weathering and erosion on Earth. Mars is a much drier, colder planet on which liquid water cannot exist very long at the surface because it will immediately begin to boil, evaporate, and freeze--all at the same time. However, new pictures from the Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) have provided an astonishing observation which suggests that liquid water may have played a role in shaping some recent gully-like features found on the slopes of various craters, troughs, and other depressions on the red planet.These pictures introduce the basic features of a martian gully. The figure on the left is an example from Mars, the figure on the right is a gully on Earth. In the Earth picture, rain water flowing under and seeping along the base of a recently-deposited volcanic ash layer has created the gully. For Mars, water is not actually seen but is inferred from the landforms and their similarity to examples on Earth.The landforms both on Earth and Mars are divided into three parts: the alcove, the channel, and the apron. Water seeps from between layers of rock on the wall of a cliff, crater, or other type of depression. The alcove forms above the site of seepage as water comes out of the ground and undermines the material from which it is seeping. The erosion of material at the site of seepage causes rock and debris on the slope above this area to collapse and slide downhill, creating the alcove.The channel forms from water and debris running down the slope from the seepage area. The point where the top of the channel meets the bottom of the alcove is, in many cases, the site where seepage is occurring. Channels are probably flushed-clean of debris from time to time by large flash floods of water released from behind an ice barrier that might form at the site of seepage during more quiescent times.The aprons are the down-slope deposits of ice and debris that were moved down the slope and through the channel

  11. Geologic Map of MTM 35337, 40337, and 45337 Quadrangles, Deuteronilus Mensae Region of Mars (United States)

    Chuang, Frank C.; Crown, David A.


    Deuteronilus Mensae, first defined as an albedo feature at lat 35.0 deg N., long 5.0 deg E., by U.S. Geological Survey (USGS) and International Astronomical Union (IAU) nomenclature, is a gradational zone along the dichotomy boundary in the northern mid-latitudes of Mars. The boundary in this location includes the transition from the rugged cratered highlands of Arabia Terra to the northern lowland plains of Acidalia Planitia. Within Deuteronilus Mensae, polygonal mesas are prominent along with features diagnostic of Martian fretted terrain, including lobate debris aprons, lineated valley fill, and concentric crater fill. Lobate debris aprons, as well as the valley and crater fill deposits, are geomorphic indicators of ground ice, and their concentration in Deuteronilus Mensae is of great interest because of their potential association with Martian climate change. The paucity of impact craters on the surfaces of debris aprons and the presence of ice-cemented mantle material imply young (for example, Amazonian) surface ages that are consistent with recent climate change in this region of Mars. North of Deuteronilus Mensae are the northern lowlands, a potential depositional sink that may have had large standing bodies of water or an ocean in the past. The northern lowlands have elevations that are several kilometers below the ancient cratered highlands with significantly younger surface ages. The morphologic and topographic characteristics of the Deuteronilus Mensae region record a diverse geologic history, including significant modification of the ancient highland plateau and resurfacing of low-lying regions. Previous studies of this region have interpreted a complex array of geologic processes, including eolian, fluvial and glacial activity, coastal erosion, marine deposition, mass wasting, tectonic faulting, effusive volcanism, and hydrovolcanism. The origin and age of the Martian crustal dichotomy boundary are fundamental questions that remain unresolved at the

  12. Determining change of bathymetry with GPR method in Ordu-Giresun, a sea-filled airport in the Black Sea, Turkey (United States)

    Kadioglu, Selma; Kagan Kadioglu, Yusuf


    Ordu-Giresun (OGU) is a newly-constructed airport, the first sea-filled airport in Turkey and in Europe, and the second airport in the world after Osaca-Japan. The airport is between Gulyalı district in Ordu city and Piraziz district in Giresun city in Black Sea -Turkey. A protection breakwater has been constructed by filling a rock approximately 7.435-m long and with an average height of 5.5 m. Then, the Black Sea has been filled until 1 m over the sea level, approximately the area is 1.770.000 m2 wide and includes a runway, aprons and taxiway covered by breakwater. The runway has a 1-m thickness, 3-km length and 45-m width, PCN84 strength, and stone mastic asphalt surface. The aprons has a 240 x 110 m length and PCN110 strength, the taxiway is 250 x 24 m wide. The airport was started to be constructed in July 2011 and it began to serve on 22th May 2015. The aim of this study was to determine the depth of the rock-filled layer and the amount of sinking of the bathymetry which has been determined before filling processing. In addition, before bathymetry determination, unconsolidated sediments had been removed from the bottom of the sea. There were four drilling points to control the sinking of the bathymetry. Therefore, six suitable Ground Penetrating Radar (GPR) profiles were measured, crossing these points with runway and aprons, using 250-MHz and 100-MHz shielded antennas. Starting points of the profiles were in the middle of the runway to merge between depth and thickness changing of the filled layer and bathymetry along the profiles. Surface topography changing was measured spaced 1 m apart with 1 cm sensitivity on each profile. At the same time, similarly the topography changing, bathymetry coordinates was re-arranged along the each profile. Topography corrections were applied to the processed radargrams and then the bottom boundary lines of the rock-filled layer were determined. The maximum height was 3.5 m according to the sea level, which was on the

  13. Estratigrafía, facies y evolución depositacional de la Formación Sauce Grande (Carbonífero Superior: Cuenca Sauce Grande, Sierras Australes, Buenos Aires, Argentina Stratigraphy, facies and depositional evolution of the Sauce Grande Formation (Upper Carboniferous: Sauce Grande Basin, Sierras Australes, Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    R. R. Andreis


    waques (Smw representan flujos de detritos finos y densos transicionales a flujos licuefactos. Las demás areniscas representan acción de oleaje o corrientes (Sr o por acreción frontal en barras transversales o dunas de arena por flujos traccionales (Sp. El comienzo de los procesos depositacionales de la Formación Sauce Grande fue caracterizado por una rápida transgresión en el Carbonífero tardío bajo condiciones de moderada subsidencia (procesos eustáticos. El megaciclo inferior se caracteriza por la sedimentación en un slope apron o debris apron localizado en las cercanías del talud continental, con fuerte agradación y rara progradación y depende del régimen termal de la base de los glaciares africanos de base fría, bajo condiciones de sistema de mar bajo. En el megaciclo medio significa una rápida fase de avance glaciar asociada a somerización isostática y el tope del apron habría sido retrabajado por olas y corrientes, creando una plataforma costa afuera casi emergente. En el megaciclo superior se produce un nuevo ascenso del mar (cortejo de mar alto, asociado al retroceso de los glaciares en el sector sudafricano y produce la transgresión tastubiana que se continúa en la Formación Piedra Azul. La disminucion del aporte se hace visible por la sistemática disminución en el espesor de las facies, una mayor frecuencia de facies Dmm1 y Smw y la interacción de depósitos pelíticos, que fueron depositados en plataformas de baja pendiente donde se han registrado avance y retroceso de los glaciares. Dos glaciohorizontes fueron identificados: el GH1 vinculado al megaciclo medio y el GH2 en el contacto entre las Formaciones Sauce Grande y Piedra Azul.The detailed analyses of the lithofacies (including their composition and the depositional processes related to the Sauce Grande Formation, represent the first siliciclastic sedimentation at the Sauce Grande Basin. Two profiles were studied: the North profile (with 826 m and the South profile (with 1095 m

  14. Evidence for Recent Liquid Water on Mars: Gullies in Crater Wall, Noachis Terra (United States)


    [figure removed for brevity, see original site] Gullies eroded into the wall of a meteor impact crater in Noachis Terra. This high resolution view (top left) from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) shows channels and associated aprons of debris that are interpreted to have formed by groundwater seepage, surface runoff, and debris flow. The lack of small craters superimposed on the channels and apron deposits indicates that these features are geologically young. It is possible that these gullies indicate that liquid water is present within the martian subsurface today.The MOC image was acquired on September 28, 1999. The scene covers an area approximately 3 kilometers (1.9 miles) wide by 6.7 km (4.1 mi) high (note, the aspect ratio is 1.5 to 1.0). Sunlight illuminates this area from the upper left. The image is located near 54.8oS, 342.5oW. The context image (above) shows the location of the MOC image on the south-facing wall of an impact crater approximately 20 kilometers (12 miles) in diameter. The context picture was obtained by the Viking 1 orbiter in 1980 and is illuminated from the upper left. The large mound on the floor of the crater in the context view is a sand dune field. The Mars Orbiter Camera high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s.A brief description of how the color was generated: The MOC narrow angle camera only takes grayscale (black and white) pictures. To create the color versions seen here, we have taken much lower resolution red and blue images acquired by the MOC's wide angle cameras, and by the Viking Orbiter cameras in the 1970s, synthesized a green image by averaging red and blue, and created a pallette of colors that represent the range of colors on Mars. We then use a relationship that correlates color and brightness to assign a color to each gray

  15. Multibeam Bathymetry of Haleakala Volcano, Maui (United States)

    Eakins, B. W.; Robinson, J.


    The submarine northeast flank of Haleakala Volcano, Maui was mapped in detail during the summers of 2001 and 2002 by a joint team from the Japan Marine Science and Technology Center (JAMSTEC), Tokyo Institute of Technology, University of Hawaii, and the U.S. Geological Survey. JAMSTEC instruments used included SeaBeam 2112 hull-mounted multibeam sonar (bathymetry and sidescan imagery), manned submersible Shinkai 6500 and ROV Kaiko (bottom video, photographs and sampling of Hana Ridge), gravimeter, magnetometer, and single-channel seismic system. Hana Ridge, Haleakala's submarine east rift zone, is capped by coral-reef terraces for much of its length, which are flexurally tilted towards the axis of the Hawaiian Ridge and delineate former shorelines. Its deeper, more distal portion exhibits a pair of parallel, linear crests, studded with volcanic cones, that suggest lateral migration of the rift zone during its growth. The northern face of the arcuate ridge terminus is a landslide scar in one of these crests, while its southwestern prong is a small, constructional ridge. The Hana slump, a series of basins and ridges analogous to the Laupahoehoe slump off Kohala Volcano, Hawaii, lies north of Hana Ridge and extends down to the Hawaiian moat. Northwest of this slump region a small, dual-crested ridge strikes toward the Hawaiian moat and is inferred to represent a fossil rift zone, perhaps of East Molokai Volcano. A sediment chute along its southern flank has built a large submarine fan with a staircase of contour-parallel folds on its surface that are probably derived from slow creep of sediments down into the moat. Sediments infill the basins of the Hana slump [Moore et al., 1989], whose lowermost layers have been variously back-tilted by block rotation during slumping and flexural loading of the Hawaiian Ridge; the ridges define the outer edges of those down-dropped blocks, which may have subsided several kilometers. An apron of volcaniclastic debris shed from

  16. Numerical simulation for hydraulic characteristics of double suspended grid in the stilling basin%双层悬栅消力池的水力特性数值模拟

    Institute of Scientific and Technical Information of China (English)

    蒋健楠; 牧振伟; 张佳祎; 牛涛; 贾萍阳


    Through physical model experiment, it is hard to get detailed hydraulic parameter data such as velocity, pressure, etc. To cope, t he paper uses fluid dynamics software FLUENT to set up RNG k- ε double-equation turbulence model to make nu-merical simulation, so as to get hydraulic parameters such as maximal water dept h, flow pattern, velocity and pressure, et c. Then makes analysis of comparison betw een mat hematical model calculat ed value and physical model experimental value, and makes a-nalysis of comparison among numerical model calculated values. T he result show s the mat hematical model calculated value and physical model experimental value are roughly identical, and the error between calculated value and experimental value is small when double suspended grid is arranged. The double suspended grid has st rong capacit y to make current generate swirl, hence small impact on apron slab by current , and low ered surge at the apron slab, larger eff ect on the pressure change, which show s double suspended grid has better performance in eliminating wave and stabilizing current.%针对物理模型试验难以得到详细的流速、压强等水力参数数据问题,利用流体力学软件 FLUENT 建立 RNG k-ε双方程紊流模型进行数值模拟,得到消力池内最大水深、流态、流速以及压强等水力参数,通过数学模型计算值与物理模型试验值对比分析以及数值模拟计算值之间对比分析,结果表明:数学模型计算值与物理模型试验值吻合较好,且布置双层悬栅时,计算值与试验值误差较小;双层悬栅使水流产生漩涡的能力较强,从而使水流对护坦冲击较小,护坦处涌浪降低,对压强变化影响较大,说明双层悬栅具有更好的消波稳流作用。

  17. CHIRP seismic reflection study of falling-stage (forced regressive) sediment wedges on the New Jersey outer continental shelf (United States)

    Santra, M.; Goff, J.; Ron, S.; Austin, J.


    High-resolution (1-12 kHz), deep-towed and hull-mounted CHIRP seismic data were collected on the New Jersey outer shelf in 2001, 2002 and 2006 as part of Office of Naval Research-funded projects. These data have imaged two well-developed, offlapping sedimentary wedges (named outer-shelf wedge and deep-shelf wedge) that are now postulated to have developed on the falling-stage limb of the last glacial cycle, during some time prior to the Last Glacial Maximum (20-22 kyrs BP). These wedges formed atop the high-amplitude, regional R horizon, a complex erosional unconformity that formed about 40,000 years ago. The outer shelf wedge is also characterized in part by an enigmatic, erose boundary separating layered horizons below from a mostly transparent section above. New Jersey shelf wedges appear analogous to forced-regressive units imaged on the Rhone shelf edge, as well as Eocene sections documented from seismic-scale outcrops on Spitsbergen Island. These examples can reach thicknesses up to 100 m on the shelf edge and uppermost slope, but usually thin rapidly downslope. Such wedges represent one of two documented mechanisms involving sand transport across a shelf margin into deeper water settings, the other being a canyonized shelf-edge. Our study will includes analysis of the CHIRP data and, if available, additional ground truth provided by short cores collected in summer 2007 at numerous intra-wedge stratigraphic horizons. Our goals are to understand the external and internal geometry of the wedges and sediment pathways across the paleo-shelf. These data should allow us to characterize margin segments that build during sea-level fall by slope-apron accretion rather than by the formation of channel-levee complexes. The literature is heavily weighted by the latter and their associated canyon systems, but information on shelf-edge attached slope aprons and how they contribute to deep-water sedimentation, and in particular the delivery of clean sands to slope settings

  18. Spatially limited mud turbidites on the Cascadia margin: segmented earthquake ruptures?

    Directory of Open Access Journals (Sweden)

    C. Goldfinger


    Full Text Available A series of 23 thin, mostly mud-silt turbidites are found interspersed between larger, well-dated and regionally correlated paleoseismic sandy turbidites that extend along most of the Cascadia margin, northwestern United States. Investigation of the structure, distribution, and sedimentology of these thin mud-silt units supports the interpretation of these units as turbidites originating on the continental slope. Interpretation of mud turbidites is inhibited by bioturbation and lower response to analytical and imaging techniques; nevertheless most of the 23 interpreted beds exhibit most of the characteristics of coarser turbidites. These characteristics include sharp bases, fining upward sequences, darker color, increased gamma and CT density and magnetic susceptibility relative to the hemipelagic background, sparse microfossils, high lithic content, and evidence of transport from marine sources on the continental slope. New core data from sites south of Rogue Apron indicate that sandy and muddy turbidites may be correlated at least 150 km south to Trinidad Plunge Pool for the period ~ 4800 yr BP to present. Many of the mud turbidites initially described at Rogue Apron coarsen southward, becoming sandy turbidites. High-resolution Chirp seismic profiles reveal that turbidite stratigraphy along the base of the southern Cascadia continental slope is continuous, with little variation for at least 240 km along strike. The Chirp data show that turbidites along the Cascadia base of slope are ubiquitous, and likely not sourced solely from submarine canyon mouths, but may also have been delivered to the proximal abyssal plain as sheet flows from the open continental slope and coalescing local sources. Regional stratigraphy reveals that hemipelagic sedimentation rates and total Holocene turbidite thickness and mass are similar at widely separated sites, yet the total thickness of the Holocene section is greater by a factor of two in southern Cascadia

  19. Evidence for Recent Liquid Water on Mars (United States)


    Gullies eroded into the wall of a meteor impact crater in Noachis Terra. This high resolution view (top left) from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) shows channels and associated aprons of debris that are interpreted to have formed by groundwater seepage, surface runoff, and debris flow. The lack of small craters superimposed on the channels and apron deposits indicates that these features are geologically young. It is possible that these gullies indicate that liquid water is present within the martian subsurface today. The MOC image was acquired on September 28, 1999. The scene covers an area approximately 3 kilometers (1.9 miles) wide by 6.7 km (4.1 mi) high (note, the aspect ratio is 1.5 to 1.0). Sunlight illuminates this area from the upper left. The image is located near 54.8S, 342.5W. The context image (above) shows the location of the MOC image on the south-facing wall of an impact crater approximately 20 kilometers (12 miles) in diameter. The context picture was obtained by the Viking 1 orbiter in 1980 and is illuminated from the upper left. The large mound on the floor of the crater in the context view is a sand dune field. The Mars Orbiter Camera high resolution images are taken black-and-white (grayscale); the color seen here has been synthesized from the colors of Mars observed by the MOC wide angle cameras and by the Viking Orbiters in the late 1970s. A brief description of how the color was generated: The MOC narrow angle camera only takes grayscale (black and white) pictures. To create the color versions seen here, we have taken much lower resolution red and blue images acquired by the MOC's wide angle cameras, and by the Viking Orbiter cameras in the 1970s, synthesized a green image by averaging red and blue, and created a pallete of colors that represent the range of colors on Mars. We then use a relationship that correlates color and brightness to assign a color to each gray level. This is only a crude approximation of

  20. Ampliación del puerto Lyttelton. Nueva Zelanda

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    Editorial, Equipo


    Full Text Available Lyttleton Port Authority has drawn up a project for the reform and construction of new wharves and breakwaters, to cater for the increasing sea traffic. The cost of the project is 4.5 million pounds. The main work consists of a 1,070 m long front wharf, built in deep water, and apt for use by large ships. The structure of the wharf consists of a filled in zone, taken from the sea, along the edge of which a row of piles has been arranged, to support the wharf itself. This has been made with hard Australian timber. But the platform over the filled in zone is built with soft local timber. The hills rising along the coastline have been traversed by two tunnels: one for the roadway and the other to take the railway. These communication lines, which save 11 km, will link the harbour with Christchurch, the most important city in South Island. The bottom, where the wharf has been made, was soft mud, awkward to contain and control. To overcome this difficulty a simple and ingenious method was adopted. Loads of stone, from nearby quarry residues, were thrown into the mud. The stones pushed out the mud in the manner of a wavefront. The mud was then dredged away, and the stone filling operation was continued. Stone had to be used as there was insufficient sand in the neighbourhood.La Junta de Obras del puerto de Lyttelton (Nueva Zelanda ha redactado un proyecto de reforma y construcción de nuevos muelles y rompeolas para absorber el creciente movimiento portuario, cuyo coste se eleva a 4,5 millones de libras. La obra consiste en un muelle frontal, continuo, de 1.070 m de longitud, en zona de gran calado, capaz para que atraquen barcos de gran tonelaje. La estructura está constituida por una zona de rellenos, ganados al mar, en cuyo frente se hallan unas filas de pilotes sobre los que descansa la estructura del muelle, construida a base de madera dura australiana; en cambio, la plataforma formada sobre el relleno es de madera blanda del país. Los montes

  1. Eluvial gold placer formation on actively rising mountain ranges, Central Otago, New Zealand (United States)

    Craw, D.; Youngson, J. H.


    Eluvial gold deposits in Central Otago, New Zealand, have formed and are still forming on the flanks of actively rising antiformal mountain ranges. These gold deposits are derived mainly by erosion and concentration of fine-grained ( soil and sequences (up to 60 m thick) of poorly sorted immature schist gravels. The gravel sequences consist mainly of matrix-supported mass flow deposits and channellised proximal fan deposits, intercalated on a 1-10 m scale. Gold is concentrated in coarse lag gravels (up to 40 cm clasts) at channel bases. Topographic slopes on the rising ranges show an evolutionary trend in space and time, from gentle weakly dissected surfaces, through slightly degraded but convex slopes, to deeply incised convex streams. Eluvial gold occurs sporadically on the gentle slopes, but the most efficient concentration processes occurred where steeper convex slopes yielded an apron of fan sediments. Gold concentration at these sites resulted from selective and localized removal ("winnowing") of most schist debris, leaving coarse lag gravels and gold. The combination of authigenic grain size increase and residual concentration ensures that the eluvial deposits retain coarse-grained gold, and that only fine-grained gold is released to the alluvial systems downstream.

  2. Terminal Pleistocene to early Holocene volcanic eruptions at Zuni Salt Lake, west-central New Mexico, USA (United States)

    Onken, Jill; Forman, Steven


    Zuni Salt Lake (ZSL) is a large maar in the Red Hill-Quemado volcanic field located in west-central New Mexico in the southwestern USA. Stratigraphic analysis of sections in and around the maar, coupled with optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C dating, indicate that ZSL volcanic activity occurred between ˜13.4 and 9.9 ka and was most likely confined to a ≤500-year interval sometime between ˜12.3 and 11.0 ka. The basal volcanic unit consists of locally widespread basaltic ash fallout interpreted to represent a violent or wind-aided strombolian eruption tentatively attributed to Cerro Pomo, a scoria cone ˜10 km south of ZSL. Subsequent eruptions emanated from vents near or within the present-day ZSL maar crater. Strombolian eruptions of multiple spatter and scoria cones produced basaltic lava and scoria lapilli fallout. Next, a phreatomagmatic eruption created the maar crater and surrounding tephra rim and apron. ZSL eruptions ended with strombolian eruptions that formed three scoria cones on the crater floor. The revised age range of ZSL is younger and more precise than the 190-24 ka 2-sigma age range derived from previous argon dating. This implies that other morphologically youthful, argon-dated volcanoes on the southern margin of the Colorado Plateau might be substantially younger than previously reported.

  3. A large and complete Jurassic geothermal field at Claudia, Deseado Massif, Santa Cruz, Argentina (United States)

    Guido, Diego M.; Campbell, Kathleen A.


    Late Jurassic geothermal deposits at Claudia, Argentinean Patagonia, are among the largest (40 km2) and most varied in the Deseado Massif, a 60,000 km2 volcanic province hosting precious metals (Au, Ag) mineralization generated during diffuse back arc spreading and opening of the South Atlantic Ocean. Both siliceous sinter and travertine occur in the same stratigraphic sequence. Deposits range from those interpreted as fluvially reworked hydrothermal silica gels, to extensive apron terraces, to a clustering of high-temperature subaerial vent mounds. Paleoenvironmentally diagnostic textures of sinters include wavy laminated, bubble mat and nodular fabrics, and for travertines comprise fossil terracette rims, wavy laminated, bubble mat, spherulitic, oncoidal, and peloidal fabrics. Of special note is the presence of relatively large (to 25 cm high), inferred subaqueous "Conophyton" structures in travertines, which serve as analogs for some Precambrian stromatolites and imply the presence of relatively deep pools maintained by voluminous spring discharges. The Claudia geothermal field is geographically and geologically linked to the Cerro Vanguardia epithermal project (total resource of ~ 7.8 million ounces Au equivalent) via proximity, similar veins, and structural linkages, making it an especially large and relevant prospect for the region. The combined Claudia-Cerro Vanguardia hydrothermal system likely represents a fortuitous alignment of focused fluid flow and structure conducive to forming a giant epithermal ore deposit, with respect to size, ore concentration and potentially duration, in the Late Jurassic of Patagonia.

  4. Paramentação cirúrgica: avaliação de sua adequação para a prevenção de riscos biológicos em cirurgias. Parte I: a utilização durante as cirurgias Surgical scrub: evaluating its adequation for preventing biological risks in surgeries. Part I: the use in surgeries

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    Marielen Silva de Oliveira Paz


    Full Text Available O estudo elaborou critérios para uso adequado da paramentação cirúrgica e avaliou, por observação sistematizada, o desempenho da equipe cirúrgica durante a cirurgia. O procedimento adotado foi válido, permitindo reconhecer aspectos positivos e problemáticos. A exceção do óculos protetor, todos os outros componentes da paramentação foram utilizados. A questão se situou na forma de utilização, onde gorros e máscaras foram mais problemáticos entre anestesistas e circulantes; avental e luvas entre cirurgiões e, principalmente, instrumentadores.The study elaborated approaches for adequated use of the surgical scrub and it evaluated, through systematized observation, the performance of the surgical team during the surgery. The adopted procedure was very valid, allowing to recognize positive and problematic aspects. Except the protecting glasses, all the other components of the surgical scrub were used. The subject located in the use form, where caps and masks were more problematic among anesthesists and circulate nurses; apron and gloves among surgeons and, mainly, scrub nurses.

  5. Passive and Active Protective Clothing against High-Power Laser Radiation (United States)

    Hennigs, C.; Hustedt, M.; Kaierle, S.; Wenzel, D.; Markstein, S.; Hutter, A.

    The main objective of the work described in this paper was the development of passive and active protective clothing for the protection of the human skin against accidental laser irradiation and of active protective curtains. Here, the passive systems consist of functional multi-layer textiles, providing a high level of passive laser resistance. In addition, the active functional multi-layer textiles incorporate sensors that detect laser exposure and are, by means of a safety control, able to deactivate the laser beam automatically.Due to the lack of regulations for testing and qualifying textiles to be used as laser PPE, test methods were defined and validated. Additionally, corresponding testing set-ups were developed.Finally, the gap with respect to standardization was bridged by the definition of a test procedure and the requirements with respect to laser PPE.The developments were demonstrated by a set of tailored functional passive and active laser-protective clothing prototypes (gloves, jackets, aprons, trousers) and active curtains as well as by a prototype testing rig, providing the possibility to perform the specified low-power and high-power textile test procedure.

  6. Somma-Vesuvius ground deformation over the last glacial cycle (United States)

    Marturano, Aldo; Aiello, Giuseppe; Barra, Diana


    Vertical ground movements at Somma-Vesuvius during the last glacial cycle have been inferred from micropalaeontological and petrochemical analyses of rock samples from boreholes drilled at the archaeological sites of Herculaneum and Pompeii as well as on the apron of the volcano and the adjacent Sebeto and Sarno Valleys. Opposing movements occurred during the periods preceding and following the Last Glacial Maximum (LGM). The uplift began 20 ka ago with marine deposits rising several tens of metres up to 25 m a.s.l., recovering previous subsidence which occurred during the Late glacial period, suggesting a strict connection between volcano-tectonic and glacial cycles. Here we present the analysis of deposits predating the LGM, which confirms subsidence of the Campanian Plain where Mt. Somma-Vesuvius is located, shows variable surface loading effects and highlights the volcano-tectonic stages experienced by the volcano. The self-balancing mechanism of the volcanic system, evolving towards an explosive, subaerial activity 60 ka ago, is testified to by a large ground oscillation in phase with sea level change during the last glacial cycle.

  7. Multiscale approach to (micro)porosity quantification in continental spring carbonate facies: Case study from the Cakmak quarry (Denizli, Turkey) (United States)

    De Boever, Eva; Foubert, Anneleen; Oligschlaeger, Dirk; Claes, Steven; Soete, Jeroen; Bertier, Pieter; Özkul, Mehmet; Virgone, Aurélien; Swennen, Rudy


    Carbonate spring deposits gained renewed interest as potential contributors to subsurface reservoirs and as continental archives of environmental changes. In contrast to their fabrics, petrophysical characteristics - and especially the importance of microporosity (quarry (Denizli, Turkey): the extended Pond, the dipping crystalline Proximal Slope Facies and the draping Apron and Channel Facies deposits formed by encrustation of biological substrate. Integrating mercury injection capillary pressure, bulk and diffusion Nuclear Magnetic Resonance (NMR), NMR profiling and Brunauer-Emmett-Teller (BET) measurements with microscopy and micro-computer tomography (µ-CT), shows that NMR T2 distributions systematically display a single group of micro-sized pore bodies, making up between 6 and 33% of the pore space (average NMR T2 cut-off value: 62 ms). Micropore bodies are systematically located within cloudy crystal cores of granular and dendritic crystal textures in all facies. The investigated properties therefore do not reveal differences in micropore size or shape with respect to more or less biology-associated facies. The pore network of the travertine facies is distinctive in terms of (i) the percentage of microporosity, (ii) the connectivity of micropores with meso- to macropores, and (ii) the degree of heterogeneity at micro- and macroscale. Results show that an approach involving different NMR experiments provided the most complete view on the 3-D pore network especially when microporosity and connectivity are of interest.

  8. Detection and Genotyping of Leuconostoc spp. in a Sausage Processing Plant. (United States)

    Padilla-Frausto, J J; Cepeda-Marquez, L G; Salgado, L M; Iturriaga, M H; Arvizu-Medrano, S M


    Some Leuconostoc spp. have the ability to produce slime and undesirable compounds in cooked sausage. The objectives of this research were to identify Leuconostoc sources in a Vienna-type sausage processing plant and to evaluate the genetic diversity of the isolated strains. Three hundred and two samples of sausage batter, sausages during processing, spoiled sausage, equipment surfaces, chilling brine, workers' gloves and aprons, and used casings were collected (March to November 2008 and February to April 2010) from a sausage processing plant. Lactic acid bacteria (LAB) were quantified, and Leuconostoc were detected using PCR. Strains were isolated and identified in Leuconostoc-positive samples. Leuconostoc strains were genotyped using randomly amplified polymorphic DNA and pulsed-field gel electrophoresis. LAB content of nonspoiled and spoiled sausage ranged from sausages showed the same genotype. One L. lactis genotype included strains isolated from spoiled sausages analyzed in April 2008 and March to April 2010. Equipment and conveyor belts constitute Leuconostoc contamination sources. Leuconostoc persistence in the sausage processing environment and in the final product suggests the existence of microbial reservoirs, possibly on equipment surfaces.

  9. Radiation exposure to cardiologists performing interventional cardiology procedures

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    Delichas, Miltiadis; Psarrakos, Kyriakos; Molyvda-Athanassopoulou, Elisabeth E-mail:; Giannoglou, Georgios; Sioundas, Anastasios; Hatziioannou, Konstantinos; Papanastassiou, Emmanouil


    Medical doctors, who practice interventional cardiology, receive a noticeable radiation dose. In this study, we measured the radiation dose to 9 cardiologists during 144 procedures (72 coronary angiographies and 70 percutaneus translumined coronary angioplasties) in two Greek hospitals. Absorbed doses were measured with TLD placed underneath and over the lead apron at the thyroid protective collar. Based on these measurements, the effective dose was calculated using the Niklason method. In addition, dose area product (DAP) was registered. The effective doses, E, were normalised to the total DAP measured in each procedure, producing the E/DAP index. The mean effective dose values were found to be in the range of 1.2-2.7 {mu}Sv while the mean E/DAP values are in the range of 0.010-0.035 {mu}Sv/Gy cm{sup 2}. The dependence of dose to the X-ray equipment, the exposure parameters and the technique of the cardiologist were examined. Taking under consideration the laboratories' annual workload, the maximum annual dose was estimated to be 1.9 and 2.8 mSv in the two hospitals.

  10. Evaluation of radiation exposure in interventional radiology (IR) using active personal dosimeters (APD); Evaluierung der Strahlenexposition in der Interventionellen Radiologie (IR) mit Hilfe von Aktiv-Personen-Dosimetern (APD)

    Energy Technology Data Exchange (ETDEWEB)

    Neugschwandtner, K. [KH Hietzing mit NZ Rosenhuegel, Wien (Austria). Inst. fuer Krankenhausphysik; TU Wien (Austria). Atominstitut; Freund, R. [KH Hietzing mit NZ Rosenhuegel, Wien (Austria). Inst. fuer Krankenhausphysik; Mertikian, G. [KH Hietzing mit NZ Rosenhuegel, Wien (Austria). Inst. fuer Radiologie; Poljanc, K. [TU Wien (Austria). Atominstitut; Ibi, B. [KA Rudolfstiftung, Wien (Austria). Stabstelle Medizinphysik


    Increased awareness of high personal dose exposure of medical staff in interventional radiology (IR) demands an assessment of radiation protection procedures. Mandatory dose monitoring systems do not allow to relate dose to specific actions of the staff as they just accumulate a total dose per month. Doses of head and limbs are expected to be high as those body parts which are not protected by the lead apron. We decided to use a measuring system by Unfors, RaySafe i2 which is built for real- time- dosimetry of scattered radiation in pulsed X-ray fields. An increased dose of the body side closer to the X-ray source (left body side) was detected. This is due to the position and the posture of the radiologist during intervention. Separating the phases of digital subtraction angiography (DSA) from those of fluoroscopy allowed not only to list the separate accumulated doses, but showed as well a big difference in dose rate. The measurements revealed the need of an improvement of common radiation protection, especially while DSA.

  11. Dome growth and coulée spreading controlled by surface morphology, as determined by pixel offsets in photographs of the 2006 Merapi eruption (United States)

    Walter, Thomas R.; Ratdomopurbo, Antonius; Subandriyo; Aisyah, Nurnaning; Brotopuspito, Kirbani Sri; Salzer, Jacqueline; Lühr, Birger


    At many explosive volcanoes viscous domes extrude, which are destroyed by complete or partial collapses. Although the growth and development of silicic domes and the associated flow and collapse mechanisms are of vital importance for understanding the occurrence and scale of pyroclastic flows, quantitative measurements of dome deformations are limited. We report on a sequence of photographs taken of a growing and deforming dome. A sequence in 2006 featuring the Merapi dome taken from similar camera positions allow the application of a digital image correlation algorithm, the aim being to detect and explore the temporal evolution of pixel offsets. The results suggest that the dome underwent deformation in two regions between September and October 2006: (i) dome growth and spreading at the volcano summit and (ii) coulée flow through a narrow canyon. The latter is associated with strain localization and flow acceleration, which indicates that the displacements and flow velocities at silicic domes are governed by the topographic structure into which the flows develop. The downslope motion of the distal parts of the flow and apron slumps continued during episodes of dome extrusion by gravitational spreading. An analysis of the 2006 Merapi dome and coulée displacement also provides insights into processes that may occur along the newly established southerly eruption direction, which also may have influenced pyroclastic flows associated with the 2010 eruption.

  12. Conceptual hydrogeological model of volcanic Easter Island (Chile) after chemical and isotopic surveys (United States)

    Herrera, Christian; Custodio, Emilio


    Most human activities and hydrogeological information on small young volcanic islands are near the coastal area. There are almost no hydrological data from inland areas, where permanent springs and/or boreholes may be rare or nonexistent. A major concern is the excessive salinity of near-the-coast wells. Obtaining a conceptual hydrogeological model is crucial for groundwater resources development and management. Surveys of water seepages and rain for chemical and environmental isotope contents may provide information on the whole island groundwater flow conditions, in spite of remaining geological and hydrogeological uncertainties. New data from Easter Island (Isla de Pascua), in the Pacific Ocean, are considered. Whether Easter Island has a central low permeability volcanic “core” sustaining an elevated water table remains unknown. Average recharge is estimated at 300-400 mm/year, with a low salinity of 15-50 mg/L Cl. There is an apron of highly permeable volcanics that extends to the coast. The salinity of near-the-coast wells, >1,000 mg/L Cl, is marine in origin. This is the result of a thick mixing zone of island groundwater and encroached seawater, locally enhanced by upconings below pumping wells. This conceptual model explains what is observed, in the absence of inland boreholes and springs.

  13. Tectonic controls on the geomorphic evolution of alluvial fans in the Piedmont Zone of Ganga Plain, Uttarakhand, India

    Indian Academy of Sciences (India)

    Pradeep K Goswami; Charu C Pant; Shefali Pandey


    The Piedmont Zone is the least studied part of the Ganga Plain.The northern limit of the Piedmont Zone is defined by the Himalayan Frontal Thrust (HFT)along which the Himalaya is being thrust over the alluvium of the Ganga Plain.Interpretation of satellite imagery,Digital Terrain Models (DTMs)and field data has helped in the identification and mapping of various morpho-tectonic features in the densely forested and cultivated Piedmont Zone in the Kumaun region of the Uttarakhand state of India.The Piedmont Zone has formed as a result of coalescing alluvial fans,alluvial aprons and talus deposits.The fans have differential morphologies and aggradation processes within a common climatic zone and similar litho-tectonic setting of the catchment area. Morphotectonic analysis reveals that the fan morphologies and aggradation processes in the area are mainly controlled by the ongoing tectonic activities.Such activities along the HFT and transverse faults have controlled the accommodation space by causing differential subsidence of the basin,and aggradation processes by causing channel migration,channel incision and shifting of depocentres.The active tectonic movements have further modified the landscape of the area in the form of tilted alluvial fan,gravel ridges,terraces and uplifted gravels.

  14. Origins of Sinuous and Braided Channels on Ascraeus Mons, Mars - A Keck Geology Consortium Undergraduate Research Project (United States)

    de Wet, A. P.; Bleacher, J. E.; Garry, W. B.


    Water has clearly played an important part in the geological evolution of Mars. There are many features on Mars that were almost certainly formed by fluvial processes -- for example, the channels Kasei Valles and Ares Vallis in the Chryse Planitia area of Mars are almost certainly fluvial features. On the other hand, there are many channel features that are much more difficult to interpret -- and have been variously attributed to volcanic and fluvial processes. Clearly unraveling the details of the role of water on Mars is extremely important, especially in the context of the search of extinct or extant life. In this project we built on our recent work in determining the origin of one channel on the southwest rift apron of Ascraeus Mons. This project, funded by the Keck Geology Consortium and involving 4 undergraduate geology majors took advantage of the recently available datasets to map and analyze similar features on Ascraeus Mons and some other areas of Mars. A clearer understanding of how these particular channel features formed might lead to the development of better criteria to distinguish how other Martian channel features formed. Ultimately this might provide us with a better understanding of the role of volcanic and fluvial processes in the geological evolution of Mars.

  15. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684; Dosimetrie pour la radioprotection en milieu medical - rapport du groupe de travail n. 9 du European radiation dosimetry group (EURADOS) - coordinated netword for radiation dosimetry (CONRAD - contrat CE fp6-12684)

    Energy Technology Data Exchange (ETDEWEB)



    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  16. Isolation and evaluation of proteolytic actinomycete isolates as novel inducers of pearl millet downy mildew disease protection (United States)

    Jogaiah, Sudisha; Kurjogi, Mahantesh; Govind, Sharathchandra Ramasandra; Huntrike, Shekar Shetty; Basappa, Vedamurthy Ankala; Tran, Lam-Son Phan


    Native endophytic actinomycetes isolated from pearl millet roots were examined for their efficacy to protect pearl millet against downy mildew. Nineteen of 39 isolates were found to be proteolytic, of which 7 strains could directly suppress the sporangium formation of Sclerospora graminicola, the pearl millet downy mildew pathogen. Thus, mycelial suspensions containing either spores or cell-free extract of these 7 isolates were used for seed-coating and -soaking treatments to test for their induction of downy mildew resistance. Results indicated that seed-coating overall provided better protection to downy mildew than seed-soaking. In both treatments, the tested isolates demonstrated differential abilities in downy mildew disease protection, with Streptomyces griseus SJ_UOM-07-09 and Streptosporangium roseum SJ_UOM-18-09 showing the highest protection rates. Additionally, the levels of disease protection conferred by the actinomycetes were just slightly lower than that of the systemic fungicide Apron, suggesting their effectiveness. Further studies revealed that the more rapid root colonization by SJ_UOM-18-09 resulted in faster and higher induced resistance in comparison with SJ_UOM-07-09 under greenhouse conditions, indicating that SJ_UOM-18-09 was superior than SJ_UOM-07-09 in inducing resistance. Results from this study provide comprehensive information on biocontrol functions of SJ_UOM- 18-09 with great potential to control downy mildew disease in pearl millet. PMID:27499196

  17. Evaluation of X-Ray Protective Measurements in Intraoral Radiography Equipped Centers in Yazd

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    D.Goodarzi Pour


    Full Text Available Statement of Problem: A few decades have past from using radiographic technology as an accurate paraclinical method and always protective measurements is applicated against ionizing radiation. As dentalradiography is a routine procedure in dentistry the importance of protective strategies is clear.Propose: The aim of this descriptive study is to evaluate the protection principles in centers which haveintraoral radiographic devices in Yazd.Material and Methods: We have considered all three aspects of practitioner, environment and patientprotection using questionnaire and visiting those centers.Results: 33/7% of dental offices ,10 clinics ,3 institution and faculty of dentistry had intraoral radiographicequipments. Stablishment of protection principles for radiographer was favorable. 7.7% of centers had x-ray room with leaded walls, 23.1% had curtain , in 69/2% of centers radiographers stood in correct position anddistance while taking radiograph. Regarding to protection of environment, beams leakage control in 23.1% dental offices, 70% of clinics, all institution and faculty of dentistry have done.Conclusion: Non of the centers used rectangular localizator, thyroid shield, film holder and just some centers used leaded apron in specific circumstances. We have concluded that patient protection constitute less consideration. Generally lack of protective consideration is related to deficient knowledge of operators. Lackof information about protection equipments causes decrease of demanding of these tools and ultimately lack of these equipments in the market.


    Directory of Open Access Journals (Sweden)

    Kuznetsova Y. A.


    Full Text Available To study the formation of plunge basin in the Cheboksary hydroplant, we used a scale model of the spillway dam and all structures in the tailrace, installed in the slot flume. When we passed the flow corresponding to the diversion flow of the hydroplant with a glance to the modeling scale, it was found that the plunge basin was formed behind the end fixing of the spillway apron. To research the dynamic facilities of hydrosystem tailrace protection against erosion, we used a small glass flume with a model of the roundcrested weir. For the experiment, the water-surface elevations were built in the flume without the weir, and the uniform motion area was established. In MathCAD software environment, the curve of the flow of measuring rectangular weir of the flume was created. Because of measurements, the curve of water surface by the flow motion through the round-crested weir was made. As the main criterion for modeling, the criterion of Froude was selected. Scale of modeling of flow parameters was determined. For testing, models of hydrodynamic profile and sail structure with streamforming sluice valves were built. The process of sand washout from the flume bottom and formation of the bottom ridges when installing the profile was photographed. Impact of the profile on the flow and its relation with the formation of the bottom topography were studied. Full-scale values of geometric parameters of the bottom ridges and their movement velocity were established as well

  19. An Algorithm for Managing Aircraft Movement on an Airport Surface

    Directory of Open Access Journals (Sweden)

    Giuseppe Maresca


    Full Text Available The present paper focuses on the development of an algorithm for safely and optimally managing the routing of aircraft on an airport surface in future airport operations. This tool is intended to support air traffic controllers’ decision-making in selecting the paths of all aircraft and the engine startup approval time for departing ones. Optimal routes are sought for minimizing the time both arriving and departing aircraft spend on an airport surface with engines on, with benefits in terms of safety, efficiency and costs. The proposed algorithm first computes a standalone, shortest path solution from runway to apron or vice versa, depending on the aircraft being inbound or outbound, respectively. For taking into account the constraints due to other traffic on an airport surface, this solution is amended by a conflict detection and resolution task that attempts to reduce and possibly nullify the number of conflicts generated in the first phase. An example application on a simple Italian airport exemplifies how the algorithm can be applied to true-world applications. Emphasis is given on how to model an airport surface as a weighted and directed graph with non-negative weights, as required for the input to the algorithm.

  20. Occupational Hepatitis B Exposure: A Peek into Indian Dental Students’ Knowledge, Opinion, and Preventive Practices

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar


    Full Text Available Objective. To determine the level of knowledge, opinions, and preventive practices followed by dental students against Hepatitis B. The study also explored if any correlation existed between knowledge, opinion, and preventive practices score. Materials and Methods. A cross-sectional study was conducted in a dental teaching institution. The subjects comprised 216 dental students. The study was conducted using a pretested, self-administered questionnaire. The questionnaire was prepared to assess knowledge, opinion, and preventive practices against Hepatitis B. Kruskal-Wallis and Kendall Tau test were performed. Results. The study found that only 44.4% of the students were vaccinated with Hepatitis B vaccine. 59.3% of the students reported washing their hands after contact with patient’s body fluids. 63.9% used personal protective measures like facemask, aprons, head cap, eye shields, and so forth, while treating patients. Median knowledge, opinion, and practice scores were found to be 5.00, 3.00, and 3.00, respectively. Significant correlation was obtained between knowledge and preventive practices score (r=0.385, p value <0.0001. Conclusion. Effective measures need to be taken to improve preventive practices of the students to prevent them from risk of Hepatitis transmission. Mandatory vaccination against Hepatitis B needs to be implemented.

  1. Ambiguity of exhaustive diagnosing of alkali-aggregate reaction for concrete revetments subjected to more aggressive factors

    Energy Technology Data Exchange (ETDEWEB)

    Olteanu, A.; Dragomir, D. [ISPH, Design and Studies Institute for Hydro Power Projects, Bucharest (Romania); Hulea, D. [Romanian Electricity Authority, Bucharest (Romania)


    On the Bistrita river, in the downstream section of Bicaz gravity dam that is 125 m high and creates a 1,500 hm{sup 3} reservoir, have been additionally built eight low head power stations interconnected by headrace and tailrace channels. These channels of 61 km total length convey water to and from the power stations and have been performed using embankment and excavation. The ground where these channels were located is of sandy clay nature with gypseous layers intercalation. The geometrical characteristics of the channels are as follows: trapezoidal section of 1V:2H slope and 6 m width at base, the water head ranging between 4 and 6 m. Both the apron and the channels slopes have been sealed using 5 x 4 m and 15 cm thick concrete slabs. Two or three slab rows are located under the water level. Channels were commissioned in 1964, and shortly after their commissioning, failures came forth and aggravated, calling for several repairs in more than 30 operation years. Concrete was exclusively damaged within the upper slabs in the area of variable water level in channel. All along the paper, there are mentioned only these slabs because the other ones in the submerged rows of slabs are practically undamaged.

  2. Applying fluvial geomorphological riffle-pool sequences concept when rebuilding the existing drop hydraulic structure

    Directory of Open Access Journals (Sweden)



    Full Text Available The paper deals with the problem of  rebuilding  the existing water straight drop  structure in Brenna on the Brennica river (Polish Carpathian mountains, which was changed into the rapid hydraulic structure. The technical project was set up in 1988 and finished in the same year. The structure was rebuilt in the field in the early autumn of 1990. One of the concepts of applied fluvial geomorphological solution was used to improve the river channel bed condition. In that case it was found that the existing hydraulic structure reducing river slope and stabilizing river bed can be changed without any harm in to semi-natural riffle structure which could be tolerated by river and organisms living in.  Artificial roughness of the slope plate of the rapid hydraulic structure was obtained by placing cobbles along all the slope apron of the structure. The diameter of cobbles was calculated applying various methods, and the optimum value for that dimension was chosen. The cobbles, used for rebuilding purposes, were taken directly from the riverbed, so that the structure is environmentally similar to the site. All work was done due to European Framework Directive for Rivers.

  3. Protective equipment of radiological protection and the worker wear; Equipamento de protecao radiologica e o desgaste do trabalhador

    Energy Technology Data Exchange (ETDEWEB)

    Cassia, Flor Rita de; Huhn, Andrea, E-mail: [Instituto Federal de Educacao, Ciencia e Tecnologia de Santa Catarina (IFSC), Florianopolis, SC (Brazil); Lima, Gelbcke Francine, E-mail: [Universidade Federal de Santa Catarina (PEN/UFSC), Florianopolis, SC (Brazil). Programa de Pos-Graduacao em Enfermagem


    This qualitative research with workers of seven hemodynamic service of Santa Catarina, Brazil aimed to analyze the use of radiological protection equipment (RPE), as well as wear to the health of workers who use these causes. The study was conducted between March 2010 and November 2010, totaling approximately 30 hours of observations. Results showed resistance to the use of RPE and also showed wear to workers' health, mainly due to the weight and discomfort they cause, as may weigh 7-9 pounds, depending on the model used. Evidenced also the absence of workers due herniated disc, back pain, and other musculo skeletal problems. These complaints, in addition to being related to the use of these protective gear also related with the time that workers remain standing for long periods on certain procedures, such as angioplasty. Given these results, the research recommended the use of these devices with materials, that are already being produced, making lighter aprons, thus avoiding fatigue and back pain and also provide greater comfort by reducing workers' resistance to its use and its adverse consequences.

  4. Numerical Modeling of Glaciers in Martian Paleoclimates (United States)

    Colaprete, A.; Haberle, R. M.; Montmessin, F.; Scheaffer, J.


    Numerous geologic features suggest the presence of ice flow on the surface of mars. These features include lobate debris aprons, concentric crater fill, and lineated valley fill. The lateral extent of these features can range from 100 meters to over 20 km. Previous work has demonstrated that these features could not have formed in current Martian conditions. It has long been speculated that changes in Mars orbital properties, namely its obliquity, eccentricity, and argument of perihelion, can result in dramatic changes to climate. Recent climate model studies have shown that at periods of increased obliquity north polar water ice is mobilized southward and deposited at low ad mid latitudes. Mid latitude accumulation of ice would provide the necessary conditions for rock glaciers to form. A time-marching, finite element glacier model is used to demonstrate the ability of ice and ice-rock mixtures to flow under Martian paleoclimate conditions. Input to this model is constrained by the NASA Ames Mars General Circulation Model (MGCM).

  5. Attitude of the Korean dentists towards radiation safety and selection criteria

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Do [Dept. of Oral and Maxillofacial Radiology and Wonkwang Dental Research Institute, College of Dentistry, Wonkwang University, Iksan (Korea, Republic of); Ludlow, John B. [Graduate Program in Oral and Maxillofacial Radiology, School of Dentistry, University of North Carolina, Chapel Hill (United States)


    X-ray exposure should be clinically justified and each exposure should be expected to give patients benefits. Since dental radiographic examination is one of the most frequent radiological procedures, radiation hazard becomes an important public health concern. The purpose of this study was to investigate the attitude of Korean dentists about radiation safety and use of criteria for selecting the frequency and type of radiographic examinations. The study included 267 Korean dentists. Five questions related to radiation safety were asked of each of them. These questions were about factors associated with radiation protection of patients and operators including the use of radiographic selection criteria for intraoral radiographic procedures. The frequency of prescription of routine radiographic examination (an example is a panoramic radiograph for screening process for occult disease) was 34.1%, while that of selective radiography was 64.0%. Dentists' discussion of radiation risk and benefit with patients was infrequent. More than half of the operators held the image receptor by themselves during intraoral radiographic examinations. Lead apron/thyroid collars for patient protection were used by fewer than 22% of dental offices. Rectangular collimation was utilized by fewer than 15% of dental offices. The majority of Korean dentists in the study did not practice radiation protection procedures which would be required to minimize exposure to unnecessary radiation for patients and dental professionals. Mandatory continuing professional education in radiation safety and development of Korean radiographic selection criteria is recommended.

  6. An Analysis of Delay and Travel Times at Sao Paulo International Airport (AISP/GRU): Planning Based on Simulation Model (United States)

    Santana, Erico Soriano Martins; Mueller, Carlos


    The occurrence of flight delays in Brazil, mostly verified at the ground (airfield), is responsible for serious disruptions at the airport level but also for the unchaining of problems in all the airport system, affecting also the airspace. The present study develops an analysis of delay and travel times at Sao Paulo International Airport/ Guarulhos (AISP/GRU) airfield based on simulation model. Different airport physical and operational scenarios had been analyzed by means of simulation. SIMMOD Plus 4.0, the computational tool developed to represent aircraft operation in the airspace and airside of airports, was used to perform these analysis. The study was mainly focused on aircraft operations on ground, at the airport runway, taxi-lanes and aprons. The visualization of the operations with increasing demand facilitated the analyses. The results generated in this work certify the viability of the methodology, they also indicated the solutions capable to solve the delay problem by travel time analysis, thus diminishing the costs for users mainly airport authority. It also indicated alternatives for airport operations, assisting the decision-making process and in the appropriate timing of the proposed changes in the existing infrastructure.

  7. Geologic map of the Sunshine 7.5' quadrangle, Taos County, New Mexico (United States)

    Thompson, Ren A.; Turner, Kenzie J.; Shroba, Ralph R.; Cosca, Michael A.; Ruleman, Chester A.; Lee, John P.; Brandt, Theodore R.


    The Sunshine 7.5' quadrangle is located in the south-central part of the San Luis Basin of northern New Mexico, in the Rio Grande del Norte National Monument, and contains deposits that record volcanic, tectonic, and associated alluvial and colluvial processes over the past four million years. Sunshine Valley, named for the small locale of Sunshine, is incised by a series of northeast-trending drainages cut into Tertiary and Quaternary alluvial deposits forming an extensive alluvial apron between the east flank of the Sangre de Cristo Mountains and the Rio Grande. These deposits predominantly overlie gently eastward-dipping lava flows of Pliocene Servilleta Basalt erupted from centers west of the map area. Servilleta Basalt lava flows terminate to the south against the elevated topography of three volcanic centers of the Taos Plateau volcanic field. From west to east these are Cerro de la Olla, Cerro Chiflo, and Guadalupe Mountain that are exposed in the southern part of the map area. Remnants of Miocene volcanic rocks are exposed near the southwestern edge of the map area and record evidence of an eroded volcanic terrain underlying deposits of the Taos Plateau volcanic field. These deposits are likely fault bounded to the east, roughly coincident with north to northwest trending, down-to-east faults in the southwestern quarter of the map area. The down-to-east normal faults reflect the basinward migration of the western margin of the Sunshine Valley sub-basin of the southern San Luis Basin.

  8. Dual guidance (CT and fluoroscopy) vertebroplasty: radiation dose to radiologists. How much and where?

    Energy Technology Data Exchange (ETDEWEB)

    Amoretti, Nicolas; Lesbats, Virginie; Marcy, Pierre-Yves; Amoretti, Marie-eve; Maratos, Yvonne; Ianessi, Antoine; Boileau, Pascal [Centre hospitalier universitaire, Radiology Department, Nice (France); Hauger, Olivier [CHU de Bordeaux, Unite d' Imagerie Osteo-articulaire, Hopital Pellegrin, Bordeaux (France)


    The goal of this study was to evaluate the radiation received by the practitioner when performing percutaneous vertebroplasty guided by CT and fluoroscopy for specific anatomical sites: orbits, hands, ankles, and thorax (under lead-lined apron). Twenty-four vertebroplasties were performed on 18 patients. The anatomical site that was most exposed to radiation was the right hand (0.37 mSv on average). This study demonstrates a significant correlation between the irradiation dose and fluoroscopy duration, reflecting both the quantity of primary-beam radiation and backscattered radiation. The right hand (P = 0.03), left hand (P = 0.02), and the left orbit (P < 0.0001) are the anatomical zones that are the most affected by the combination of these two types of radiation, with cumulative irradiation doses of 0.45, 0.2, and 0.14 mSv, respectively. There was a significant correlation between the patient weight and radiation of the left hand (P = 0.03), the left orbit (P = 0.03), and the thorax (P = 0.02), confirming the major influence of backscattered radiation. The most irradiated anatomical sites limiting the number of interventions are the left orbit and the right hand. (orig.)

  9. Do children trust based on group membership or prior accuracy? The role of novel group membership in children's trust decisions. (United States)

    Elashi, Fadwa B; Mills, Candice M


    Two experiments examined how an informant's group membership can influence children's trust decisions. Participants (3- to 7-year-olds, N=162) were assigned to either the red or blue group based on their selection of a red or blue apron and watched an in-group and out-group informant provide conflicting names for a set of novel objects. When asked which informant they would prefer to rely on for new information, nearly all age groups trusted the in-group informant. Children then watched as each informant varied in accuracy by labeling either all or none of four familiar items accurately and were then asked which informant's labels they preferred for learning new information. When the in-group informant had previously demonstrated accuracy, children continued to trust the in-group informant for new information. In contrast, when the in-group informant had previously demonstrated inaccuracy, children were unsure who to trust, with only 6- and 7-year-olds showing a decrease in their trust for the inaccurate in-group informant. These findings demonstrate that group membership can skew how children encode new information and can make children uncertain about whom to trust for information.

  10. Exposure to and precautions for blood and body fluids among workers in the funeral home franchises of Fort Worth, Texas. (United States)

    Nwanyanwu, O C; Tabasuri, T H; Harris, G R


    In 1982 the Centers for Disease Control published a set of recommendations and measures to protect persons working in health care settings or performing mortician services from possible exposure to the human immunodeficiency virus. This study of a number of funeral homes in the Fort Worth area was designed to determine the level of exposure of funeral home workers to blood and other body fluids and also to assess existing protective measures and practices in the industry. Workers in 22 funeral home franchises were surveyed with a predesigned questionnaire. Eighty-five responses from 20 of the 22 establishments were received. All 85 respondents admitted exposure of varying degrees to blood and body fluids. Sixty persons (70%) admitted heavy exposure, that is, frequent splashes. Analysis of the responses showed that 81 of 85 (95.3%) persons consistently wore gloves while performing tasks that might expose them to blood or other body fluids. Of the 60 persons who were heavily exposed, 43 wore long-sleeved gowns, 27 wore waterproof aprons, 17 surgical masks, and 15 goggles. The study further revealed that 52.9% (45/85) of the respondents had sustained accidental cuts or puncture wounds on the job. In light of these findings it is important to target educational efforts to persons in this industry to help them minimize their risks of infection with blood and body fluid borne infections.

  11. Heathrow Terminal 5 Excavation Archive (Data Paper

    Directory of Open Access Journals (Sweden)

    Framework Archaeology


    Full Text Available Framework Archaeology is a Joint Venture agreement between Oxford Archaeology (OA and Wessex Archaeology (WA to provide archaeological services to BAA (formerly British Airports Authority, now Heathrow Airport Holdings Ltd. Given the potential scale of some of BAA's projects, the joint venture enables Framework Archaeology to draw on the full resources of both OA and WA, including site staff, specialist managers, administrative support, and technical facilities. In 1993, BAA plc and Heathrow Airport Limited submitted a joint planning application to develop an additional passenger terminal complex (Terminal 5, together with the provision of aircraft aprons and taxiways, and include the realignment of rivers and landscaping. The resulting archaeological excavations were undertaken as three main phases of work. Excavations in 1996 by the Museum of London Archaeology Service of approximately 4 ha of sludge stockpile areas (site code POK96. Between 1999-2000 Framework Archaeology excavated approximately 21 ha in the Perry Oaks sludge works and adjacent areas (WPR98. Framework Archaeology also undertook excavations between 2002-2007 as part of the construction of Terminal 5 (PSH02, TEC05 covering a further 50 hectares. Importantly the aim of the Terminal 5 archaeological programme was to move beyond the description and recovery of archaeological remains and to arrive at an understanding of the history of human inhabitation and the practical ways in which people established their presence in the material, social and political conditions of their day.

  12. FLAMES仿真系统中目标毁伤仿真的实现%Target Damage Simulation Method In FLAMES Simulation System

    Institute of Scientific and Technical Information of China (English)

    魏江龙; 杨世荣; 张明刚; 汤达明


    为了构建FLAMES中的目标毁伤仿真系统,在对FLAMES仿真系统体系结构分析的基础上,通过研究FLAMES中目标毁伤仿真的相关模型、函数及计算方法,归纳出目标毁伤仿真的实现流程.最后以飞机轰炸停机坪目标的毁伤计算为例,具体实现了FLAMES中的目标毁伤仿真.%To develop target damage simulation in FLAMES, based on analysis the system structure of FLAMES, by studying the relative models、 functions and the calculating methods of target damage simulation in FLAMES, shows the target damage simulation flow. At last, with an damage calculation example of aircraft drop bombs on apron, the paper carries out the target damage simulation method in FLAMES,.

  13. Preliminary Correlation Map of Geomorphic Surfaces in North-Central Frenchman Flat, Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Bechtel Nevada


    This correlation map (scale = 1:12,000) presents the results of a mapping initiative that was part of the comprehensive site characterization required to operate the Area 5 Radioactive Waste Management Site, a low-level radioactive waste disposal facility located in northern Frenchman Flat at the Nevada Test Site. Eight primary map units are recognized for Quaternary surfaces: remnants of six alluvial fan or terrace surfaces, one unit that includes colluvial aprons associated with hill slopes, and one unit for anthropogenically disturbed surfaces. This surficial geology map provides fundamental data on natural processes for reconstruction of the Quaternary history of northern Frenchman Flat, which in turn will aid in the understanding of the natural processes that act to develop the landscape, and the time-frames involved in landscape development. The mapping was conducted using color and color-infrared aerial photographs and field verification of map unit composition and boundaries. Criteria for defining the map unit composition of geomorphic surface units are based on relative geomorphic position, landform morphology, and degree of preservation of surface morphology. The bedrock units identified on this map were derived from previous published mapping efforts and are included for completeness.

  14. Decreased dose of radiation to dogs during acquisition of elbow radiographs using draped shielding. (United States)

    Nemanic, S; Nixon, B K; Francis, R A; Farmer, R H; Harlan, D L; Baltzer, W I


    Protective lead equivalent shielding of patients is not routinely used in veterinary radiology. The goal of this study was to determine whether the use of lead equivalent shielding results in a significant reduction in dose of radiation to dogs during acquisition of elbow radiographs. The authors measured radiation doses in the primary beam and over and under protective lead equivalent shielding that was placed at the level of the eyes, body and gonads during acquisition of elbow radiographs using 0.01 mSv sensitivity dosimetry badges. Shielding consisted of 0.5 mm lead equivalent aprons and thyroid shields placed over bodies and eyes, respectively. All badges in the primary beam-detected radiation. Shielding significantly decreased the dose of radiation with significantly less scatter and tube leakage radiation detected under compared with over shielding (P=0.0001). The dose of radiation detected over shielding was significantly greater than zero (P=0.0001), while that under shielding did not differ significantly from zero (P=0.09). Based on these results, the authors recommend protective shielding be used on veterinary patients during radiography.

  15. Measurement of staff doses in interventional procedures using LiF TL-detectors and a special diode dosemeter

    Energy Technology Data Exchange (ETDEWEB)

    Parviainen, T.; Toivonen, M.; Kosunen, A.; Karppinen, J. [Radiation and Nuclear Safety Authority, Helsinki (Finland); Ylitalo, A. [Satakunta Central Hospital, Division for Cardiology, Pori (Finland)


    Personal doses vary considerably among the operational staff in cardiac examination procedures and interventions. Correspondingly, the fluoroscopy time may vary from a few minutes to more than 1 hour. Large personal doses in the range of 35 - 41 mSv were registered to some interventional radiologists and cardiologists in 2001 in Finland. Measurement of doses per intervention from hands, shoulders and ankles (parts of the body outside the lead apron) are therefore of interest, but small and highly sensitive dosemeters have not been commonly available for reliable and practical measurements. Thermoluminescent detectors of LiF:MgCu,P are sensitive enough, but residual luminescence from previous uses of detectors and the dose collected from natural background radiation between preparation for use and readout may be significant sources of uncertainty. The company Unfors Instrumens AB (Billdal, Sweden) has designed a light weight diode dosemeter with long cables between detectors and the electronic part for simultaneous measurement of doses from various parts of the body. The aim of this work is to report doses of the operating staff per a cardiac examination or intervention and study the capabilities of the diode dosemeter in staff dose measurements. (orig.)

  16. Tectonic and sedimentary evolution of Bransfield Basin, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Jeffers, J.D.; Thomas, M.A.; Anderson, J.B.


    The Bransfield basin is the youngest and best developed of a series of extensional marginal basins on the Pacific margin of the Antarctic Peninsular. Marine geophysical data collected over five seasons show that the back arc is segmented laterally into three subbasins separated by transform zones. These subbasins differ in width, depth, structural style, and seisimicity and are correlated with three different age segments of subducted sea floor. The distribution of principal sedimentary environments, identified from high-resolution seismic reflection data, and their associated lithofacies, seen in piston cores and surface sediment samples, is controlled largely by the tectonic segmentation of the basins. Terrigenous sediments prograde into the basin from the continent side, whereas sediment gravity-flow processes deliver volcaniclastic material from the arc to slope-base aprons and to fan lobes at the outlets of fiords. Organic-rich muds fill the deep basin; their proximity to submarine volcanic centers produces thermogenic hydrocarbons. Understanding the recent tectonic and sedimentary evolution of the Bransfield basin may help refine interpretations of the older deformed marginal basin sequences of southern South America, the Scotia Arc, and the Antarctic Peninsula.

  17. Major types of deep-water reservoirs from the Eastern Brazilian rift and passive margin basis

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, Carlos H.L. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Exploracao e Producao


    Turbidites and associated deep-water facies comprise the most important petroleum reservoirs in Brazil. They contain in place volumes of 57.2 billion bbl of oil, and 27.5 trillion cubic feet of gas, and total reserves of 12.5 billion bbl of oil, and 8.3 trillion cubic feet of gas. Brazilian petroleum-bearing turbidites occur in Carboniferous/Permian, glaciomarine pre-rift (interior cratonic) successions, Neocomian to Aptian, lacustrine rift successions and Upper Albian to Lower Miocene, marine passive margin successions. Most of the petroleum accumulations are distributed along the eastern Brazilian margin, which tectonic and sedimentary evolution is linked to the Neocomian breakup of Gondwana and the subsequent opening of the South Atlantic Ocean. Turbidites comprise 553 production zones from 171 oil and/or gas fields, mostly concentrated in the Campos, Reconcavo, Sergipe/Alagoas, and Espirito Santo basins. This paper presents an overview of the sedimentary facies, high-resolution stratigraphy, sand body geometry, and reservoir heterogeneities of the major types of Brazilian deep-water reservoirs, which include gravel/sand-rich, turbidite channel complexes, though-confined, gravel/sand-rich turbidite lobes, gravel/sand-rich turbidite and debrite aprons, deposits of sand-rich, lacustrine density underflows, deposits of sand/mud-rich debris flows, and deposits of sandy bottom currents. (author)

  18. Playa Del Rey oil field, Los Angeles County, California-- natural gas storage

    Energy Technology Data Exchange (ETDEWEB)

    Barnds, R.M.


    The Playa del Rey oil field is on Santa Monica Bay, about 15 miles SW. of Los Angeles. The sedimentary rocks of the field were deposited on the flanks and over the ridge of an erosional surface of Franciscan schist. A NW.-trending anticline resulted from deposition and compaction over the ridge. An apron of schistose clastic material was deposited in the littoral zone at the base of the ridge and in embayments formed by the lateral channels. Conformably overlying the basal conglomerate (productive lower zone) and unconformably overlying the schist is a dark brown, compact shale with abundant small lenticular streaks and nodules of calcium phosphate. The rest of the Miocene rock column is composed of about 500 ft of hard, compact black shale and sandy shale, which is conformably overlain by the typical Los Angeles-basin Pliocene and Pleistocene rocks. The upper oil zone is in the lower Pliocene. The Playa del Rey Field is productive from both the lower zone and from sedimentary rocks of the anticline. There are widely varied porosity and permeability values throughout the Del Rey Hills area. That part chosen for the gas-storage project is where the basal conglomerate overlying the Franciscan schist is overlain by the nodular shale.

  19. Statistical survey of ten criteria established by Portaria 453 of Brazilian Ministry of Health for dentists who use X-rays; Levantamento estatistico de 10 criterios estabelecidos pela Portaria 453 MS para os odontologos que utilizam raios-X

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Claudio Domingues de, E-mail: [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)


    In July 1998, the Ministry of Health (MS) published the Guidelines for Radiological Protection in Medical and Dental Radiodiagnosis that became known as Portaria 453 - Ordinance 453. This study is designed to evaluate the dentists of Rio de Janeiro on the knowledge and application of the criteria laid down by Ordinance. For this, it was sent to dentists, a form with 13 questions. The issues are related to the use of personal protective clothing (VPI), working procedures for the exam and processing of the image, radioprotection training and quality control. Of 1528 dentists, only 40% have a copy of the Ordinance. Regarding the use of VPI, 94% has lead apron and 76% thyroid shield. Only 63% of dentists observe patients during exposure to X-rays. In 96% of doctor's rooms the revelation of the film is made in a portable box, 71% of these use the visual method to stop processing. The results show the need for greater dissemination of the Ordinance by the odontologist's associations; for an educational work on the topics discussed and training that allow the dentists be prepared to apply the correct work procedures in the production of diagnostic imaging with X-rays.

  20. Evaluation of Prerequisite Programs Implementation and Hygiene Practices at Social Food Services through Audits and Microbiological Surveillance. (United States)

    Garayoa, Roncesvalles; Yánez, Nathaly; Díez-Leturia, María; Bes-Rastrollo, Maira; Vitas, Ana Isabel


    Prerequisite programs are considered the most efficient tool for a successful implementation of self-control systems to ensure food safety. The main objective of this study was to evaluate the implementation of these programs in 15 catering services located in Navarra and the Basque Country (regions in northern Spain), through on-site audits and microbiological analyses. The implementation of the prerequisite program was incomplete in 60% of the sample. The unobserved temperature control during both the storage and preparation of meals in 20% of the kitchens reveals misunderstanding in the importance of checking these critical control points. A high level of food safety and hygiene (absence of pathogens) was observed in the analyzed meals, while 27.8% of the tested surfaces exceeded the established limit for total mesophilic aerobic microorganisms (≤100 CFU/25 cm²). The group of hand-contact surfaces (oven door handles and aprons) showed the highest level of total mesophilic aerobic microorganisms and Enterobacteriaceae, and the differences observed with respect to the food-contact surfaces (work and distribution utensils) were statistically significant (P food workers' hands, lower levels of microorganisms were observed in the handlers wearing gloves (that is, for Staphylococcus spp we identified 43 CFU/cm2 on average compared with 4 CFU/cm2 (P food handlers, through specific activities such as informal meetings and theoretical-practical sessions adapted to the characteristics of each establishment.

  1. Dosimetry studies on prototype 241Am sources for brachytherapy. (United States)

    Nath, R; Gray, L


    Sealed sources of 241Am emit primarily 60 keV photons which, because of multiple Compton scattering, produce dose distributions in water that are comparable to those from 226Ra or 137Cs. However, americium gamma rays can be shielded by thin layers of high atomic number materials since the half value layer thickness is only 1/8th of a mm of lead for americium gamma rays as compared to a value of 12 mm for 226Ra gamma rays. This may allow effective in vivo shielding of critical organs, for example; the bladder can be partially shielded by hypaque solution, and the rectum and sigmoid colon by barium sulfate. In addition, the exposure to medical personnel involved in intracavitary application and patient care may be reduced substantially by the use of relatively thin lead aprons and light weight, portable shields. To investigate the feasibility of 241Am sources for intracavitary irradiation, dosimetry studies on prototype 241Am sources have been performed and a computer model for the determination of dose distributions around encapsulated cylindrical sources of 241Am has been developed and tested. Results of dosimetry measurements using ionization chambers, lithium fluoride thermoluminescent dosimeters, a scanning scintillation probe, and film dosimetry, confirm theoretical predictions that these sources can deliver dose rates adequate for intracavitary irradiation. Further dosimetry measurements in simulated clinical situations using lead foils and test tubes filled with hypaque or barium sulfate, confirm the predicted effectiveness of in vivo shielding which can be readily achieved with 241Am sources.

  2. Assessment of canyon wall failure process from multibeam bathymetry and Remotely Operated Vehicle (ROV) observations, U.S. Atlantic continental margin: Chapter 10 in Submarine mass movements and their consequences: 7th international symposium part II (United States)

    Chaytor, Jason D.; Demopoulos, Amanda W. J.; Ten Brink, Uri; Baxter, Christopher D. P.; Quattrini, Andrea M.; Brothers, Daniel S.; Lamarche, Geoffroy; Mountjoy, Joshu; Bull, Suzanne; Hubble, Tom; Krastel, Sebastian; Lane, Emily; Micallef, Aaron; Moscardelli, Lorena; Mueller, Christof; Pecher, Ingo; Woelz, Susanne


    Over the last few years, canyons along the northern U.S. Atlantic continental margin have been the focus of intensive research examining canyon evolution, submarine geohazards, benthic ecology and deep-sea coral habitat. New high-resolution multibeam bathymetry and Remotely Operated Vehicle (ROV) dives in the major shelf-breaching and minor slope canyons, provided the opportunity to investigate the size of, and processes responsible for, canyon wall failures. The canyons cut through thick Late Cretaceous to Recent mixed siliciclastic and carbonate-rich lithologies which impart a primary control on the style of failures observed. Broad-scale canyon morphology across much of the margin can be correlated to the exposed lithology. Near vertical walls, sedimented benches, talus slopes, and canyon floor debris aprons were present in most canyons. The extent of these features depends on canyon wall cohesion and level of internal fracturing, and resistance to biological and chemical erosion. Evidence of brittle failure over different spatial and temporal scales, physical abrasion by downslope moving flows, and bioerosion, in the form of burrows and surficial scrape marks provide insight into the modification processes active in these canyons. The presence of sessile fauna, including long-lived, slow growing corals and sponges, on canyon walls, especially those affected by failure provide a critical, but as yet, poorly understood chronological record of geologic processes within these systems.

  3. The practice of PPE amongst fourth year medical students at A&E. Where are we?

    Directory of Open Access Journals (Sweden)

    Thiruselvi Subramaniam


    Full Text Available Background: This cross sectional study was done toidentify the areas of lack of knowledge, practice andawareness of students about the effective use of personalprotective equipment (PPE.Methods: A total of 40 students were selected whenthey were posted to the accident and emergency unit(A&E in Seremban Hospital; all of them answereda questionnaire and were observed unaware on theeffective use of PPE in the A&E.Results: We found that17.5% of students were unawareof the right technique of removing the gloves after aprocedure and 25% of students were unaware of safetyof hand washing. During invasive procedures, 12.5 %of students did not wash their hands before invasiveprocedures, 65% did not wear aprons and 57.5% did notwear masks. During non- invasive procedures more than25% of students did not wash hands before or after theprocedures.Conclusion: There is still significant lack of knowledgein students about the effective use of PPE that needs tobe addressed.

  4. Comparison of the isozyme phenotypes of the morphologically similar ticks Amblyomma cajennense and A. imitator (Acari: Ixodidae) from south Texas. (United States)

    Hilburn, L R; Gunn, S J; Castillo, C


    A survey of Amblyomma Koch tick populations in southern Texas revealed that A. imitator Kohls was restricted to the two most southern counties, but that A. cajennense (Fabricius) ranged at least as far north as Kingsville, Tex. Females of the two species could be distinguished by the presence of chitinous tubercles on the festoons of A. cajennense and the presence of projections over both sides of the apron of the genital aperture in A. imitator. Males were distinguished by size, ornamentation, and the elongate ventral scutes of A. imitator. In addition, six enzymes, AATA, ACONA, IDH2, LDH, MPI, and PEP, were diagnostic for the two species and two others, aGPD and ACONC, had high diagnostic values. Resulting interspecific divergence was significant, I = 0.582. Genetic variability was higher in A. imitator (h = 0.092) than in A. cajennense (h = 0.057), but neither species exhibited marked interpopulation divergence (I = 0.991 in A. imitator, I = 0.994 in A. cajennense).

  5. Nesting biology of Paravespa rex (von Schulthess 1924) (Hymenoptera: Vespidae: Eumeninae) in the Crimea, Ukraine. (United States)

    Fateryga, Alexander V; Ivanov, Sergey P


    Paravespa rex is the only species of the wasp genus Paravespa that occurs in Europe. Females of this species nest in clay loam soil of proluvial terraces and deluvial aprons of badlands. The nests are vertical burrows 10-12 cm deep, surmounted by turrets of two distinct architectural forms: funnel-shaped and curved. The nests contain 1-3 vertical cells (mean-1.9) not different from the other parts of nest burrow. An egg is laid onto the bottom of the cell without attaching; it stands vertically via the moist adhesive surface of the bottom and then with the help of the position of the first prey, which is laid around the egg. The species is univoltine; prepupae hibernate in the cocoon for one or several years. Females hunt for caterpillars of two species of the noctuid genus Heliotis; 3-7 caterpillars (mean-3.7) are stored per cell. Adult feeding is recorded on flowers of Thymus tauricus. Males look for females at their water-collecting sites. Only a third of the cells are successful; the other ones are damaged by rain and the gold wasp, Chrysis valesiana, parasitizing in the nests. Nest-building and hunting activity of the species is described with the duration of certain nesting acts. Nesting biology of Paravespa species, rarity of P. rex, turret function, egg position, and measures for species conservation are discussed.

  6. SURFACE AREA AND MICRO-ROUGHNESS OF VOLCANIC ASH PARTICLES: A case study, Acigol Volcanic Complex, Cappadocia, Central Turkiye (United States)

    Ersoy, O.; Aydar, E.; Sen, E.; Atici, G.


    Every single ash particle may convey information about its own formation environment and conditions. Certain features on particles may give a hint about the fragmentation regime, the intensity of fragmentation and quantity of water that partakes in the fragmentation process, etc. On this account, this study majored in the analysis on finer pyroclastic material, namely volcanic ash particles. Here, we used volcanic ash particles from Quaternary Acigol Volcanic complex (West of Nevsehir, Cappadocia, Central Turkiye). Quaternary Acigol Volcanic complex lies between the towns of Nevsehir and Acigol. It consists of a shallow caldera, a thick pyroclastic apron, seven obsidian dome clusters, and scattered cinder cones and associated lavas (Druitt et al., 1995). The products of explosive volcanism of the region were distinguished as two main Quaternary tuffs by a recent study (Druitt et al., 1995). Samples are from ashfall beds in a sequence of intercalated pumice fall, ashfall, and ignimbrite beds. In this study in order to achieve surface properties of volcanic ash particles, surface areas and micro-roughness of ash particles were measured on digital elevation models (DEM) reconstructed from stereoscopic images acquired on Scanning Electron Microscope (SEM) at varying specimen tilt angles. Correlation between surface texture of volcanic ash particles and eruption characteristics was determined.

  7. Study of Airport Special Vehicles Localization Algorithm Based on WSN%基于无线传感器网络的机场特种车定位算法研究

    Institute of Scientific and Technical Information of China (English)

    孙毅刚; 隋莉敏


    The localization of airport special vehicles is an important portion of airport surface monitor on the airport apron.The paper realized the real-time localization of the airport special vehicles on WSN.Arming at environment influence problem of RSSI, Gaussian model was applied to choice RSSI values.A space compensating model makes all nodes in a flat surface.A modified weighted cancroids localization algorithm improves the precision of localization.The simulation result show the modified weighted cancroids localization algorithm has met the requirements of the airport special vehicles localization accuracy.%机场停机坪内特种车辆的定位是机场场面监控的重要部分,基于无线传感器网络实现对机场特种车辆的实时定位.针对RSSI值易受环境影响问题,采用高斯模型对采集的RSSI值进行筛选,通过空间补偿模型将节点映射到同一平面,并提出了修正加权质心定位算法,修正权重系数,提高定位精度.仿真结果表明,该算法能够满足机场特种车定位精度的要求.

  8. Utilized friction when entering and exiting a dry and wet bathtub. (United States)

    Siegmund, Gunter P; Flynn, Jim; Mang, Daniel W; Chimich, Dennis D; Gardiner, John C


    Bathtubs and showers are a common source of unintentional slips and falls. The goal of this study was to quantify the friction used by barefoot subjects entering and exiting a typical bathtub/shower enclosure under dry and wet conditions. Sixty subjects (30F, 30M) from three age groups (20-30 years, 40-50 years, 60-70 years) entered and exited a slip-resistant bathtub using six movement patterns (three entering and three exiting the tub) simulating actual use. Force plates installed in the tub floor and the slip-resistant deck outside the tub measured ground reaction forces, from which utilized friction and double support times were calculated. Overall, utilized friction varied from 0.102 to 0.442 (0.235+/-0.057) and was 0.058+/-0.040 lower in wet than dry conditions across all movement patterns (p0.14). Double support times were longer in older subjects than in both young and middle-aged subjects for all movement patterns (p<0.0009) and longer under wet than dry conditions for all entry movements (p<0.0001). These data suggest that subjects regard the wet condition as more hazardous than the dry condition and adapt their utilized friction accordingly. These data also show that older subjects are more cautious than young subjects when confronted with the dual tasks of stepping over the tub's apron and transitioning to a surface perceived to be more slippery.

  9. [Measuring intraoperative radiation exposure of the trauma surgeon. Measuring eye, thyroid gland and hand with highly sensitive thermoluminescent detectors]. (United States)

    Fuchs, M; Modler, H; Schmid, A; Dumont, C; Stürmer, K M


    A prospective study of 24 operative procedures involving minimal invasive techniques and fluoroscopic guidance was undertaken in order to measure the radiation exposure to the primary surgeon. Radiation was monitored with the use of high sensitive thermoluminescent dosimeters. At the spots of dosimetry (eyes, thyroid gland, hand and genitals under lead apron) the dose was uniformly low and ranged from 0.6 muSv at the eyes to 259.3 muSv at the hand. The dose is determined by the duration of fluoroscopy and the amount of scattered rays, which in turn depends on the volume being x-rayed. On the basis of our results there is no likelihood of exceeding the limits of safety regulations even in a very busy operative environment, although a statistically increased incidence of thyroid cancer or a radiation-induced glaucoma is present. In vitro measurements with irradiation of a phantom resulted in the following recommendations: 1) fluoroscopy should be performed using the magnification-mechanism of the x-ray apparatus, 2) during lateral fluoroscopy the primary surgeon should be positioned close to the image intensifier. At least the surgeon should be familiar with the technique of closed reduction and instrumentation to reduce the duration of fluoroscopy which proved to be the most important factor for the amount of the radiation exposure.

  10. 环氧涂层材料在厄瓜多尔 CCS水电站中的应用%Epoxy Coating Material Applied In Ecuador CCS Hydropower Station

    Institute of Scientific and Technical Information of China (English)

    陈攀; 费雷刚; 孙永波


    针对SK手刮聚脲、YEC环氧防护涂层材料、YEM环氧砂浆及高强混凝土4种材料进行水下冲磨试验,根据实验结果对比分析:YEC环氧防护涂层材料具有较好的施工环境适应性和对混凝土更好的粘结性能,施工方便。选择使用YEC环氧涂层材料进行CCS水电站冲沙闸下游护坦混凝土的抗冲磨防护。%The Erosion and Abrasion Resistance test include SK -PU coating,YEC Epoxy coating , YEM Epoxy mortar,High-strength Concrete four materials.based on comparative analysis of the ex-perimental results:YEC epoxy coating material has better environmental adaptability and better bond-ing properties of concrete , convenient construction .YEC epoxy coating material has been used for E-rosion and Abrasion Resistance of Downstream Apron of Flushing Sluice , Ecuador CCS Hydropower Station.

  11. Baseline survey of health prophylaxis and management practices on Swiss dairy farms. (United States)

    Gordon, P; Kohler, S; Reist, M; van den Borne, B; Menéndez González, S; Doherr, M


    Health prophylaxis management practices have acquired a major role in the success of dairy herd health programs, however, little is known about the scope and level of implementation on Swiss dairy farms. The main objective of this study was therefore to provide a general overview of the most important preventive measures which are currently being used on these farms. In March 2011, an online survey with 75 questions was sent to 2'285 randomly selected Swiss dairy farmers. Response rate by question ranged from 35 to 53 %. Within this study, answers were compared between dairy farms with a tie-stall (n = 739) and farms with a free-stall (n = 458). Homeopathic treatments were used by 51 % of the dairy farmers and antibiotic dry cow treatments by 94 %. Farmers with a tie-stall tended to carry out more prophylactic treatments against external parasites, vaccinated their cows more frequently against Clostridium chauvoei and Moraxella bovis, and carried out claw trimming more frequently than dairy farmers with a free-stall. A higher proportion of dairy farmers with a free-stall had a written feeding plan, carried out regular feed analysis, wore an apron and rubber gloves during milking, and carried out post milking teat disinfection more frequently than dairy farmers with a tie-stall. The data collected in this survey could assist in improving future dairy health communication campaigns in Switzerland.

  12. Avaliação da exposição dos médicos à radiação em procedimentos hemodinâmicos intervencionistas Evaluation of radiation exposure to physicians during hemodynamic interventional procedures

    Directory of Open Access Journals (Sweden)

    Leonardo Peres da Silva


    Full Text Available OBJETIVO: Este trabalho avalia a distribuição de dose recebida por médicos envolvidos em procedimentos hemodinâmicos de angioplastia coronária e coronariografia. A influência de alguns fatores, como o modo de fluoroscopia pulsado ou contínuo e o local de acesso à veia e/ou artéria, foi investigada. MATERIAIS E MÉTODOS: Para esta avaliação foram feitas medições utilizando dosímetros termoluminescentes de LiF:Mg,Ti, posicionados em sete diferentes pontos do corpo dos profissionais: mãos, joelho, pescoço, testa e tórax, por dentro e por fora do avental de chumbo. A dose foi avaliada, por exame, nos médicos que executaram os procedimentos (30 de angioplastia e 60 de coronariografia. Os dosímetros termoluminescentes foram calibrados na grandeza operacional equivalente de dose pessoal, Hp(d, nas profundidades de 0,07, 3 e 10 mm. RESULTADOS: Os resultados mostram a importância do uso do protetor de tireóide e avental de chumbo para a redução da dose recebida pelos médicos. As doses dos profissionais que executaram procedimentos por via braquial usando modo contínuo de fluoroscopia foram mais altas do que os que executaram por via femoral e modo pulsado de fluoroscopia. CONCLUSÃO: Este estudo mostra a necessidade de medidas adicionais de proteção e a implementação de mecanismos de treinamento em proteção radiológica para os médicos que trabalham com cardiologia intervencionista.OBJECTIVE: The present study evaluates the dose distribution received by physicians involved in hemodynamic procedures of coronary angiography and coronariography. The influence of some factors such as pulsed or continuous fluoroscopy mode and vein and/or artery access site was investigated. MATERIALS AND METHODS: Measurements have been performed with LiF:Mg,Ti thermoluminescent dosimeters placed on seven different sites of the practitioners' bodies: hands, left knee, neck, forehead and chest, under and over the lead apron. Radiation doses for

  13. The Surface of Venus is Saturated With Ancient Impact Structures, and its Plains are Marine Sediments (United States)

    Hamilton, W. B.


    Conventional interpretations of Venus are forced to fit dubious pre-Magellan conjectures that the planet is as active internally as Earth and preserves no ancient surface features. Plate tectonics obviously does not operate, so it is commonly assumed that the surface must record other endogenic processes, mostly unique to Venus. Imaginative systems of hundreds of tiny to huge rising and sinking plumes and diapirs are invoked. That much of the surface in fact is saturated with overlapping large circular depressions with the morphology of impact structures is obscured by postulating plume origins for selected structures and disregarding the rest. Typical structures are rimmed circular depressions, often multiring, with lobate debris aprons; central peaks are common. Marine-sedimentation features are overlooked because dogma deems the plains to be basalt flows despite their lack of source volcanoes and fissures. The unearthly close correlation between geoid and topography at long to moderate wavelengths requires, in conventional terms, dynamic maintenance of topography by up and down plumes of long-sustained precise shapes and buoyancy. A venusian upper mantle much stronger than that of Earth, because it is cooler or poorer in volatiles, is not considered. (The unearthly large so-called volcanoes and tessera plateaus often are related to rimmed circular depressions and likely are products of impact fluidization and melting.) Plains-saturating impact structures (mostly more obvious in altimetry than backscatter) with diameters of hundreds of km are superimposed as cookie-cutter bites, are variably smoothed and smeared by apparent submarine impact and erosion, and are differentially buried by sediments compacted into them. Marine- sedimentation evidence includes this compaction; long sinuous channels and distributaries with turbidite- channel characteristics and turbidite-like lobate flows (Jones and Pickering, JGSL 2003); radar-smooth surfaces and laminated aspect in

  14. 居民对健康支持工具使用情况的影响因素分析%Factors affecting the use of health utensils among residents

    Institute of Scientific and Technical Information of China (English)

    李金涛; 曹承建; 张琼; 张文辉; 王咪咪


    Objective To understand factors affecting the use of health utensils and provide promoting strategies for using the utensils. Methods The method of proportional probability sampling was applied to select 4 000 urban households from 10 urban districts of Hangzhou. The questionnaire of self-designed survey included the use of health related book, salt restriction cans, oil control pots, weight scale and kitchen apron. Factors affecting the use of health utensils were analyzed by logistic regression. Results A total of 3 340 (83.5%) households received the health utensils. Among the families with utensils, 74. 5% , 62. 0%, 59. 4%, 45. 2% and 77. 1% of families read health related books and used salt restriction cans, oil control pots, weight scale and kitchen aprons. Factors affecting the use of health utensils were the knowledge of the amount of daily salt intake, the risk awareness of high salt intake, the knowledge of the appropriate amount of cooking oil intake, conscious efforts to restrict salt and cooking oil in daily life and the convenience of the use of health utensils. Conclusion Education and the free%目的 了解居民对健康支持工具的使用情况并分析其使用影响因素,为推广健康支持工具提供政策建议参考.方法 采用概率比例规模抽样方法,在杭州市10个城区共调查4 000户居民,对收到健康支持工具的居民资料进行logistic回归多因素分析.结果 本研究共有3 340(83.5%)户居民收到健康支持工具;其中,健康读本、限盐罐、控油壶、体重尺、围裙使用率分别占74.5%、62.0%、59.4%、45.2%、77.1%,是否使用健康支持工具(包括限盐罐、控油壶、体重尺、围裙、健康读本共五件套)的影响因素有:是否知晓食盐健康摄入量、是否知晓口味偏咸的危害、是否知晓食用油健康摄入量、日常生活中是否有意识限盐、是否有意识控油及健康意识高低和自觉工具使用难易度等.结论

  15. Technical Analysis and Performance Evaluation of Sliding Sleeve Seal%滑套密封技术分析与性能评估∗

    Institute of Scientific and Technical Information of China (English)

    余海燕; 雷中清; 冯强; 党伟; 周俊然; 王益山


    As an important tool of the slicing mining technology of petroleum and natural gas,sliding sleeves’ sealing performance directly affects on the slicing mining effect.Different sealing solutions used for the sliding sleeves were classi⁃fied and summarized,including the O⁃ring seal,lip seal,special seal and their different combination sealing forms.The seal⁃ing performances were evaluated for different forms of seals from five aspects,such as sealing effect,shearing resistance, wear resistance,service life and cost.By considering the five indicators synthetically,sleeve seals can choose simple star⁃rings,star⁃rings with apron,U⁃rings,double triangle rings of Tecom,and other forms of seals.Taking economy and practica⁃bility into consideration,simple O⁃rings and O⁃rings with flat apron are more applicable at slow speed and low pressure, and combination of O⁃rings and trapezoidal rings,fabric reinforced rubber combination V⁃ring seals,K⁃type seals of Tecom Manchester,T⁃rings of TeKanggelai are usually used at high pressure and large speed change.%滑套作为石油天然气分层开采技术的重要工具,其密封性能直接影响着施工的效果。对用于滑套的不同密封方案进行总结分类,包括O形圈密封、唇形密封、特殊型密封及其不同的组合密封形式;从密封效果、抗剪切性、耐磨性、使用寿命、成本5项指标对各类密封进行性能评估。综合考虑5项指标,滑套密封可选用简单星形密封圈、星形密封圈加挡圈、 U型密封圈、特康双三角密封圈等密封形式;而从经济实用方面来考虑,低压且速度不高时,可使用简单O形圈、 O形密封圈加平挡圈;压力较高且速度变化较大时,可使用O形圈和梯形环的组合、 V形夹织物橡胶组合密封圈、 K型特康斯特密封圈、 T型特康格来圈。

  16. Turbidite event history--Methods and implications for Holocene paleoseismicity of the Cascadia subduction zone (United States)

    Goldfinger, Chris; Nelson, C. Hans; Morey, Ann E.; Johnson, Joel E.; Patton, Jason R.; Karabanov, Eugene; Gutierrez-Pastor, Julia; Eriksson, Andrew T.; Gracia, Eulalia; Dunhill, Gita; Enkin, Randolph J.; Dallimore, Audrey; Vallier, Tracy; Kayen, Robert; Kayen, Robert


    Turbidite systems along the continental margin of Cascadia Basin from Vancouver Island, Canada, to Cape Mendocino, California, United States, have been investigated with swath bathymetry; newly collected and archive piston, gravity, kasten, and box cores; and accelerator mass spectrometry radiocarbon dates. The purpose of this study is to test the applicability of the Holocene turbidite record as a paleoseismic record for the Cascadia subduction zone. The Cascadia Basin is an ideal place to develop a turbidite paleoseismologic method and to record paleoearthquakes because (1) a single subduction-zone fault underlies the Cascadia submarine-canyon systems; (2) multiple tributary canyons and a variety of turbidite systems and sedimentary sources exist to use in tests of synchronous turbidite triggering; (3) the Cascadia trench is completely sediment filled, allowing channel systems to trend seaward across the abyssal plain, rather than merging in the trench; (4) the continental shelf is wide, favoring disconnection of Holocene river systems from their largely Pleistocene canyons; and (5) excellent stratigraphic datums, including the Mazama ash and distinguishable sedimentological and faunal changes near the Pleistocene-Holocene boundary, are present for correlating events and anchoring the temporal framework. Multiple tributaries to Cascadia Channel with 50- to 150-km spacing, and a wide variety of other turbidite systems with different sedimentary sources contain 13 post-Mazama-ash and 19 Holocene turbidites. Likely correlative sequences are found in Cascadia Channel, Juan de Fuca Channel off Washington, and Hydrate Ridge slope basin and Astoria Fan off northern and central Oregon. A probable correlative sequence of turbidites is also found in cores on Rogue Apron off southern Oregon. The Hydrate Ridge and Rogue Apron cores also include 12-22 interspersed thinner turbidite beds respectively. We use 14C dates, relative-dating tests at channel confluences, and

  17. Radiation exposure of the radiological staff caused by radiography of small mammals, reptiles and birds; Untersuchungen zur Strahlenexposition des radiologisch taetigen Personals bei der Radiographie von Heimtieren, Reptilien sowie Zier- und Wildvoegeln

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, Yvonne


    maximum measured doses were 11.4 μSv for the eye-lenses, 11.5 μSv for the thyroid, 5.67 μSv for the thoracic region under the lead apron, 3.47 μSv for the thoracic region above the lead apron, 1.86 μSv for the gonads, 182 μSv for the fingers and 2.05 μSv for the foot. The median of all dose values was 0.53 μSv. The analysis of the results showed that radiation exposure of staff during X-raying small mammals, reptiles and birds was very low. Dose values at the eye-lenses, thyroid region and the fingers were regularly measurable and were annotated. The most exposed body regions were the fingers, which were closest to the primary x-ray field during X-raying. All in all, the measured dose values were in the range of a few microsievert. There was no influence of dose-influencing-parameters on the dose. There was a slight, non-significant trend that heavier patients caused higher dose values because of more scattered radiation, and also a higher kV-number was correlated with an increase in dose rate. The comparison between measuring positions above and under the protection clothes showed that even the values measured above the protection clothes were low. Furthermore, the protective effect of protection clothes was pointed out. Therefore it is not necessary to optimize the radiation protection measures in the clinic. The results of the estimation of the annual radiation exposure of the radiological staff underlined that the exposure is well below the national dose limits for occupationally exposed persons. The conservative maximum effective dose amounted to less than 1 % of the civilizing radiation exposure of all citizens in Germany. Moreover the evaluation of the results concerning the anesthetic risk of the patients showed that routinely X-raying without any anesthesia is justifiable.

  18. Integrative geomorphological mapping approach for reconstructing meso-scale alluvial fan palaeoenvironments at Alborz southern foothill, Damghan basin, Iran (United States)

    Büdel, Christian; Majid Padashi, Seyed; Baumhauer, Roland


    Alluvial fans and aprons are common depositional features in general Iranian geomorphology. The countries major cities as well as settlements and surrounding area have often been developed and been built up on this Quaternary sediment covers. Hence they periodically face the effects of varying fluvial and slope-fluvial activity occurring as part of this geosystem. The Geological Survey of Iran therefore supports considerable efforts in Quaternary studies yielding to a selection of detailed mapped Quaternary landscapes. The studied geomorphologic structures which are settled up around an endorheic basin in Semnan Province represent a typical type of landform configuration in the area. A 12-km-transect was laid across this basin and range formation. It is oriented in north-south direction from the southern saltpan, called "Kavir-e-Haj Aligholi"/"Chah-e-Jam" ("Damghan Kavir"), across a vast sandy braided river plain, which is entering from the north east direction of the city of Shahroud. At its northern rim it covers alluvial sediment bodies, which are mainly constituted by broad alluvial aprons, fed by watersheds in Alborz Mountains and having their genetic origins in Mio-/Pliocene times. During this study a fully analytical mapping system was used for developing a geodatabase capable of integrating geomorphological analyses. Therefore the system must provide proper differentiation of form, material and process elements as well as geometric separation. Hence the German GMK25 system was set up and slightly modified to fit to the specific project demands. Due to its structure it offers most sophisticated standards and scale independent hierarchies, which fit very well to the software-determinated possibilities of advanced geodatabase applications. One of the main aspects of mapping Quaternary sediments and structures is to acquire a proper description and systematic correlation and categorization of the belonging mapping-objects. Therefore the team from GSI and

  19. Ecological Risk Evaluation of Heavy Metals of the Typical Dredged Mud in Shanghai%上海市典型疏浚泥重金属生态风险评价

    Institute of Scientific and Technical Information of China (English)

    唐庆丽; 程金平; 高昊旻; 姚磊; 蒋真毅; 吴旸; 谢翠松; 梁海; 王鹤


    In order to discuss the potential ecological risk of heavy metals of the typical dredged mud in Shanghai, the Hakanson potential ecological risks method was used to analyse and assess the potential ecological risks of heavy metals, including Hg,Cd,Cu, Pb,As,Cr and Zn in dredged mud from the following three areas-the dock apron of Huangpu River, the mouth of the Yangtze River and inland waterways. The results showed that the mean values of ecological risk index ( Eri) of the seven heavy metals are 20. 05 , 17.49,8.82,5.71,4.68,1.74 and 1. 13 , respectively, all of which belonged to the low ecological risk; Cd ( one location in inland waterways) and Hg( three locations in the mouth of the Yangtze River and one location in inland waterways) are the most hazardous elements, with the Eri >40, which belonged to the medium ecological risk or the high ecological risk, and other elements belonged to the low ecological risk. From the results of ecological risk indices( ERI) of the heavy metals in Shanghai dredged mud, the risk of the heavy metals belonged to the low ecological risk. The ERI of inland waterways, the mouth of the Yangtze River and the dock apron of the Huangpu River were 81. 4 ,57. 7 and 52. 5 , respectively, which all belong to the low ecological risk.%为了探讨上海典型疏浚泥中重金属的生态风险,本研究利用生态风险指数法对黄浦江、长江口、内河航道疏浚泥中Hg、Cd、Cu、Pb、As、Cr和Zn进行风险评价.结果表明,7种重金属的潜在生态风险系数(Eri)从大到小平均值分别为20.05、17.49、8.82、5.71、4.68、1.74和1.13,均属轻微生态危害;从采样区域来看各区域重金属的Eri均小于40,属轻微生态危害;从采样点来看,除内河航道和长江口个别点Cd(1个点)和Hg(4个点)Eri>40,属于中度生态危害或强生态危害,其余均为轻微生态危害.从潜在生态风险指数(ERI)的评价结果来看:疏浚泥中重金属潜在生态风险较低,均属于轻

  20. Coniform stromatolites from geothermal systems, North Island, New Zealand (United States)

    Jones, B.; Renaut, R.W.; Rosen, Michael R.; Ansdell, K.M.


    Coniform stromatolites are found in several sites in the Tokaanu and Whakarewarewa geothermal areas of North Island, New Zealand. At Tokaanu, silicification of these stromatolites is taking place in Kirihoro, a shallow hot springfed pool. At Whakarewarewa, subfossil silicified coniform stromatolites are found on the floor of "Waikite Pool" on the discharge apron below Waikite Geyser, and in an old sinter succession at Te Anarata. The microbes in the coniform stromatolites from Tokaanu, Waikite Pool, and Te Anarata have been well preserved through rapid silicification. Nevertheless, subtle differences in the silicification style induced morphological variations that commonly mask or alter morphological features needed for identification of the microbes in terms of extant taxa. The coniform stromatolites in the New Zealand hotspring pools are distinctive because (1) they are formed of upward tapering (i.e., conical) columns, (2) neighboring columns commonly are linked by vertical sheets or bridges, (3) internally, they are formed of alternating high- and low-porosity laminae that have a conical vertical profile, and (4) Phormidium form more than 90% of the biota. As such, they are comparable to modern coniform mats and stromatolites found in the geothermal systems of Yellowstone National Park and ice-covered lakes in Antarctica. Formation of the coniform stromatolites is restricted to pools that are characterized by low current energy and a microflora that is dominated by Phormidium. These delicate and intricate stromatolites could not form in areas characterized by fast flowing water or a diverse microflora. Thus, it appears that the distribution of these distinctive stromatolites is controlled by biological constraints that are superimposed on environmental needs.

  1. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers.

    Directory of Open Access Journals (Sweden)

    Sigurd Mikkelsen

    Full Text Available Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain, and previous results may be sensitive to reporting and selection bias. We examined the relation between meniscal lesions and cumulative exposure to heavy lifting in a prospective register-based study with complete follow-up and independent information on exposure and outcome. We established a cohort of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort. The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time hospital diagnosis or surgery of a meniscal lesion. Baggage handlers had a higher incidence of meniscal lesions than the referents. Within baggage handlers spline regression showed that the incidence rate ratio was 1.91 (95% confidence interval: 1.29-2.84 after five years as a baggage handler and then decreased slowly to reach unity after approximately 30 years, adjusted for effects of potential confounders. This relation between baggage handling and meniscal lesions was present for work on the apron which involves lifting in a kneeling or squatting position, but not in the baggage hall, which only involves lifting in standing positions. The results support that long-term heavy lifting in a kneeling or squatting position is a risk factor for the development of

  2. A Cohort Study on Meniscal Lesions among Airport Baggage Handlers. (United States)

    Mikkelsen, Sigurd; Brauer, Charlotte; Pedersen, Ellen Bøtker; Alkjær, Tine; Koblauch, Henrik; Simonsen, Erik Bruun; Helweg-Larsen, Karin; Thygesen, Lau Caspar


    Meniscal lesions are common and may contribute to the development of knee arthrosis. A few case-control and cross-sectional studies have identified knee-straining work as risk factors for meniscal lesions, but exposure-response relations and the role of specific exposures are uncertain, and previous results may be sensitive to reporting and selection bias. We examined the relation between meniscal lesions and cumulative exposure to heavy lifting in a prospective register-based study with complete follow-up and independent information on exposure and outcome. We established a cohort of unskilled men employed at Copenhagen Airport or in other companies in the metropolitan Copenhagen area from 1990 to 2012 (the Copenhagen Airport Cohort). The cohort at risk included 3,307 airport baggage handlers with heavy lifting and kneeling or squatting work tasks and 63,934 referents with a similar socioeconomic background and less knee-straining work. Baggage handlers lifted suitcases with an average weight of approximately 15 kg, in total approximately five tonnes during a 9-hour workday. The cohort was followed in the National Patient Register and Civil Registration System. The outcome was a first time hospital diagnosis or surgery of a meniscal lesion. Baggage handlers had a higher incidence of meniscal lesions than the referents. Within baggage handlers spline regression showed that the incidence rate ratio was 1.91 (95% confidence interval: 1.29-2.84) after five years as a baggage handler and then decreased slowly to reach unity after approximately 30 years, adjusted for effects of potential confounders. This relation between baggage handling and meniscal lesions was present for work on the apron which involves lifting in a kneeling or squatting position, but not in the baggage hall, which only involves lifting in standing positions. The results support that long-term heavy lifting in a kneeling or squatting position is a risk factor for the development of symptomatic

  3. Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular room (United States)

    Kim, Jong Bin; Lee, Jaehoon


    Purpose The aim of the present study was to identify the radiation hazards to vascular surgeons and scrub nurses working in mobile fluoroscopy equipped hybrid vascular operation rooms; additionally, to estimate cumulative cancer risk due to certain exposure dosages. Methods The study was conducted prospectively in 71 patients (53 men and 18 women) who had undergone vascular intervention at our hybrid vascular theater for 6 months. OEC 9900 fluoroscopy was used as mobile C-arm. Exposure dose (ED) was measured by attaching optically stimulated luminescence at in and outside of the radiation protectors. To measure X-ray scatter with the anthropomorphic phantom model, the dose was measured at 3 distances (20, 50, 100 cm) and 3 angles (horizontal, upward 45°, downward 45°) using a personal gamma radiation dosimeter, Ecotest CARD DKG-21, for 1, 3, 5, 10 minutes. Results Lifetime attributable risk of cancer was estimated using the approach of the Biological Effects of Ionizing Radiation report VII. The 6-month ED of vascular surgeons and scrub nurses were 3.85, 1.31 mSv, respectively. The attenuation rate of lead apron, neck protector and goggle were 74.6%, 60.6%, and 70.1%, respectively. All cancer incidences among surgeons and scrub nurses correspond to 2,355 and 795 per 100,000 persons. The 10-minute dose at 100-cm distance was 0.004 mSv at horizontal, 0.009 mSv at downward 45°, 0.003 mSv at upward 45°. Conclusion Although yearly radiation hazards for vascular surgeons and scrub nurses are still within safety guidelines, protection principles can never be too stringent when aiming to minimize the cumulative harmful effects. PMID:28289670

  4. Morphological changes at Colima volcano caused the 2015 Hurricane Patricia investigated by repeated drone surveys and time lapse cameras (United States)

    Walter, Thomas R.; Navarro, Carlos; Arambula, Raul; Salzer, Jackie; Reyes, Gabriel


    Colima is one of the most active volcanoes in Latin America, with frequent dome building eruptions and pyroclastic flow hazards. In July 2015 Colima had a new climax of eruptive activity, profoundly changing the summit morphology and redistributing volcanic ashes to the lower volcano apron. These unconsolidated ashes are prone to be mobilized by rainfall events, and therefore required close monitoring. A major hurricane then had landfall in western Mexico in October 2015, accumulating c. 450 mm of rainfall at a meteorological station at Nevado de Colima (3461 m) and immense lahar and ash deposit mobilization from Colima Volcano. Hurricane Patricia was the largest ever recorded category 5 storm, directly crossing the state of Colima. Due to the successful scientific advice and civil protection no human losses were directly associated to this lahar hazards. We have conducted drone overflight in profound valleys that directed the pyroclastic flows and lahars two days before and three days after the hurricane. Over 8,000 close range aerial photographs could be recorded, along with GPS locations of ground stations. Images were processed using the structure from motion methodology, and digital elevation models compared. Erosion locally exceeded 10 m vertically and caused significant landscape change. Mass mobilization unloaded the young pyroclastic deposits and led to significant underground heat loss and water boiling in the affected areas. We also firstly report the use of camera array set-ups along the same valley to monitor lahar deposition and erosion from different perspectives. Combining these photos using photogrammetric techniques allow time series of digital elevation change studies at the deepening erosional ravines, with large potential for future geomorphic monitoring. This study shows that photo monitoring is very useful for studying the link of volcano landscape evolution and hydrometerological extremes and for rapid assessment of indirect volcanic hazards.

  5. The ABC transporter ABCG29 is involved in H2O2 tolerance and biocontrol traits in the fungus Clonostachys rosea. (United States)

    Dubey, Mukesh; Jensen, Dan Funck; Karlsson, Magnus


    For successful biocontrol interactions, biological control organisms must tolerate toxic metabolites produced by themselves or plant pathogens during mycoparasitic/antagonistic interactions, by host plant during colonization of the plant, and xenobiotics present in the environment. ATP-binding cassette (ABC) transporters can play a significant role in tolerance of toxic compounds by mediating active transport across the cellular membrane. This paper reports on functional characterization of an ABC transporter ABCG29 in the biocontrol fungus Clonostachys rosea strain IK726. Gene expression analysis showed induced expression of abcG29 during exposure to the Fusarium spp. mycotoxin zearalenone (ZEA) and the fungicides Cantus, Chipco Green and Apron. Expression of abcG29 in C. rosea was significantly higher during C. rosea-C. rosea (Cr-Cr) interaction or in exposure to C. rosea culture filtrate for 2 h, compared to interaction with Fusarium graminearum or 2 h exposure to F. graminearum culture filtrate. In contrast with gene expression data, ΔabcG29 strains did not display reduced tolerance towards ZEA, fungicides or chemical agents known for inducing oxidative, cell wall or osmotic stress, compared to C. rosea WT. The exception was a significant reduction in tolerance to H2O2 (10 mM) in ΔabcG29 strains when conidia were used as an inoculum. The antagonistic ability of ΔabcG29 strains towards F. graminearum, Fusarium oxysporum or Botrytis cinerea in dual plate assays were not different compared with WT. However, in biocontrol assays ΔabcG29 strains displayed reduced ability to protect Arabidopsis thaliana leaves from B. cinerea, and barley seedling from F. graminearum as measured by an A. thaliana detached leaf assay and a barley foot rot disease assay, respectively. These data show that the ABCG29 is dispensable for ZEA and fungicides tolerance, and antagonism but not H2O2 tolerance and biocontrol effects in C. rosea.

  6. SU-E-I-57: Estimating the Occupational Eye Lens Dose in Interventional Radiology Using Active Personal Dosimeters Worn On the Chest

    Energy Technology Data Exchange (ETDEWEB)

    Omar, A; Marteinsdottir, M; Kadesjo, N; Fransson, A [Dept. of Medical Physics, Karolinska University Hospital, Stockholm (Sweden)


    Purpose: To provide a general formalism for determination of occupational eye lens dose based on the response of an active personal dosimeter (APD) worn at chest level above the radiation protection apron. Methods: The formalism consists of three factors: (1) APD conversion factor converting the reading at chest level (APDchest) to the corresponding personal dose equivalent at eye level, (2) Dose conversion factor transferring the measured dose quantity, Hp(10), into a dose quantity relevant for the eye lens dose, (3) Correction factor accounting for differences in exposure of the eye(s) compared to the exposure at chest level (e.g., due to protective lead glasses).The different factors were investigated and evaluated based on phantom and clinical measurements performed in an x-ray angiography suite for interventional cardiology. Results: The eye lens dose can be conservatively estimated by assigning an appropriate numerical value to each factor entering the formalism that in most circumstances overestimates the dose. Doing so, the eye lens dose to the primary operator and assisting staff was estimated in this work as D-eye,primary = 2.0 APDchest and D-eye,assisting = 1.0 APDchest, respectively.The annual eye lens dose to three nurses and one cardiologist was estimated to be 2, 2, 2, and 13 mSv (Hp(0.07)), respectively, using a TLD dosimeter worn at eye level. In comparison, using the formalism and APDchest measurements, the respective doses were 2, 2, 2, and 16 mSv (Hp(3)). Conclusion: The formalism outlined in this work can be used to estimate the occupational eye lens dose from the response of an APD worn on the chest. The formalism is general and could be applied also to other types of dosimeters. However, the numerical value of the different factors may differ from those obtained with the APD’s used in this work due to differences in dosimeter properties.

  7. Experimental studies of local scour in the pressurized OCF below a wooden log across the flow

    Indian Academy of Sciences (India)

    Soumen Maji; Prashanth Reddy Hanmaiahgari; Subhasish Dey


    The proposed study examined and reviewed the published experimental results related to clear water scour below a cylinder across the flow. It also highlighted the limitations of existing methods for estimating the scour depth below a submerged cylinder. In the present study, experiments were performed for 50% and 75% submergences of a 70 mm diameter cylinder in the free surface flow over a uniform sand bed with $d_{50}\\ =$ 0.98 mm downstream of an apron. Based on the experimental results, an empirical equation was proposed to estimate the amount of gap flow between the cylinder and the bed for an equilibrium scour for a given flow depth and sediment properties. Measured scour profile consisted of a scour hole and immediately followed by a dune. However, no general sediment transport was occurring away from the cylinder due to the undisturbed bed shear stress less than or equal to the critical shear stress required for the sediment entrainment. Different submergence ratios of the cylinder resulted in different longitudinal and vertical extensions of the scour hole and the dune. The maximum equilibrium scour depth occurred when the cylinder is fully submerged in the unidirectional flow with water depth equals to the cylinder diameter. The non-dimensional measured scour profiles were found to be similar. The characteristic lengths of the scour hole and the dune were computed analytically by approximating the measured scour profile by third degree polynomials. The computed non-dimensional scour profiles compared satisfactorily with the measured profiles. It was found that analytical non-dimensional scour profiles were identical for a given diameter of a cylinder with different submergences for the same flow conditions.

  8. Melt water-driven gully formation in Moni Crater, Mars (United States)

    Glines, N. H.; Gulick, V. C.; Freeman, P. M.


    The southern mid-latitude 5-km diameter Moni Crater (47S, 18.5E) in Noachis Terra is typical of many small craters of this latitude, containing both gullies on its walls and arcuate ridges on its floor. Interpreted by Howard (2003) and others as remnant terminal moraines, these ridges are located at the distal margins of the gullies' debris aprons, suggesting a possible association in their formation. Our results suggest that these arcuate ridges might result from the downslope movement of ice-rich deposits that pushed pre-existing ice-rich crater floor deposits into a moraine-like ridge. The pre-existing floor deposits can be interpreted to be a form of sublimated Concentric Crater Fill (CCF), which would have been among the first ice deposits to erode the Moni Crater walls. If we assume the arcuate ridges to be glacial moraines, then we can also assume the same processes that elevated the ridges also provided melt water to form the gullies. There is evidence that water and ice deposit-related processes incised the gully headwalls, exposing bedrock, plucking boulders, and initiating fractures, through ice-wedging or surface abrasion. HiRISE images (~25cm/pixel) show shallow gullies extending several tens of meters beyond the crater rim, exploiting possible fractures or lineation in the rock. Melt water from these ice deposits, or snow melt, is a potential gully formation mechanism that would be consistent with the shallow runoff-like drainage morphology extending above the gully alcoves and beyond the crater rim. An initial phase of rapid melt water flows would also explain the wider degraded remnant channels we see on the crater slopes. The more gradual melting of ice frozen around headwall rocks could explain a secondary phase of melt water flows that form the more-recent channels.

  9. A new design of a lead-acrylic shield for staff dose reduction in radial and femoral access coronary catheterization

    Energy Technology Data Exchange (ETDEWEB)

    Eder, H. [Deptartment of Radiation Protection (Germany); Seidenbusch, M.C.; Treitl, M. [Muenchen Univ. Clinical Center (Germany). Inst. for Clinical Radiology; Gilligan, P. [Mater Private Hospital, Dublin (Ireland). Medical Physics


    Today's standard radiation protection during coronary angiography and percutaneous coronary interventions is the combined use of lead acrylic shields and table-mounted lower body protection. Ambient dose measurements, however, have shown that these protection devices need improvement. Using an anthropomorphic physical phantom, various scenarios were investigated with respect to personnel exposure: (a) enlarging the shield (b) adding a flexible protective curtain to the bottom side of the shield, and (c) application of radioprotective patient drapes. For visualization of the dose reduction effect, Monte Carlo simulations were performed. The flexible curtain in contact with the patient's body reduces the ambient dose rate at the operator's position by up to (87.5 % ± 7.1) compared to the situation with the bare shield. The use of both the flexible curtain and the patient drape reduces the ambient dose rate by up to (90.8 % ± 7). Similar results were achieved for the assisting personnel when they were positioned next to the operator. In addition, the enlarged shield provides better protection of the head region of tall operators. Adding a flexible protective curtain to the bottom side of the shield can protect operators from high doses, especially for body parts which are not protected by lead aprons, e.g. head, and eye lenses. This may be important with respect to lower dose limits for eye lenses in future. The protective effect in real-life working conditions is still being evaluated in an ongoing clinical study.

  10. Ebola virus disease surveillance and response preparedness in northern Ghana

    Directory of Open Access Journals (Sweden)

    Martin N. Adokiya


    Full Text Available Background: The recent Ebola virus disease (EVD outbreak has been described as unprecedented in terms of morbidity, mortality, and geographical extension. It also revealed many weaknesses and inadequacies for disease surveillance and response systems in Africa due to underqualified staff, cultural beliefs, and lack of trust for the formal health care sector. In 2014, Ghana had high risk of importation of EVD cases. Objective: The objective of this study was to assess the EVD surveillance and response system in northern Ghana. Design: This was an observational study conducted among 47 health workers (district directors, medical, disease control, and laboratory officers in all 13 districts of the Upper East Region representing public, mission, and private health services. A semi-structured questionnaire with focus on core and support functions (e.g. detection, confirmation was administered to the informants. Their responses were recorded according to specific themes. In addition, 34 weekly Integrated Disease Surveillance and Response reports (August 2014 to March 2015 were collated from each district. Results: In 2014 and 2015, a total of 10 suspected Ebola cases were clinically diagnosed from four districts. Out of the suspected cases, eight died and the cause of death was unexplained. All the 10 suspected cases were reported, none was confirmed. The informants had knowledge on EVD surveillance and data reporting. However, there were gaps such as delayed reporting, low quality protective equipment (e.g. gloves, aprons, inadequate staff, and lack of laboratory capacity. The majority (38/47 of the respondents were not satisfied with EVD surveillance system and response preparedness due to lack of infrared thermometers, ineffective screening, and lack of isolation centres. Conclusion: EVD surveillance and response preparedness is insufficient and the epidemic is a wake-up call for early detection and response preparedness. Ebola surveillance remains

  11. High Resolution Imaging Science Experiment (HiRISE) observations of glacial and periglacial morphologies in the circum-Argyre Planitia highlands, Mars (United States)

    Banks, Maria E.; McEwen, Alfred S.; Kargel, Jeffrey S.; Baker, Victor R.; Strom, Robert G.; Mellon, Michael T.; Gulick, Virginia C.; Keszthelyi, Laszlo; Herkenhoff, Kenneth E.; Pelletier, Jon D.; Jaeger, Windy L.


    The landscape of the Argyre Planitia and adjoining Charitum and Nereidum Montes in the southern hemisphere of Mars has been heavily modified since formation of the Argyre impact basin. This study examines morphologies in the Argyre region revealed in images acquired by the High Resolution Imaging Science Experiment (HiRISE) camera and discusses the implications for glacial and periglacial processes. Distinctive features such as large grooves, semicircular embayments in high topography, and streamlined hills are interpreted as glacially eroded grooves, cirques, and whalebacks or roche moutonnée, respectively. Large boulders scattered across the floor of a valley may be ground moraine deposited by ice ablation. Glacial interpretations are supported by the association of these features with other landforms typical of glaciated landscapes such as broad valleys with parabolic cross sections and stepped longitudinal profiles, lobate debris aprons interpreted as remnant debris covered glaciers or rock glaciers, and possible hanging valleys. Aligned boulders observed on slopes may also indicate glacial processes such as fluting. Alternatively, boulders aligned on slopes and organized in clumps and polygonal patterns on flatter surfaces may indicate periglacial processes, perhaps postglaciation, that form patterned ground. At least portions of the Argyre region appear to have been modified by processes of ice accumulation, glacial flow, erosion, sediment deposition, ice stagnation and ablation, and perhaps subsequent periglacial processes. The type of bedrock erosion apparent in images suggests that glaciers were, at times, wet based. The number of superposed craters is consistent with geologically recent glacial activity, but may be due to subsequent modification.

  12. Occupational and patient exposure as well as image quality for full spine examinations with the EOS imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Damet, J., E-mail:; Fournier, P.; Monnin, P.; Sans-Merce, M.; Verdun, F. R.; Baechler, S. [Institute of Radiation Physics, Lausanne University Hospital, Lausanne 1007 (Switzerland); Ceroni, D. [Department of Paediatrics, Division of paediatric orthopaedic, University Hospitals of Geneva, Geneva 1205 (Switzerland); Zand, T. [Department of Radiology, Division of paediatric radiology, University Hospitals of Geneva, Geneva 1205 (Switzerland)


    Purpose: EOS (EOS imaging S.A, Paris, France) is an x-ray imaging system that uses slot-scanning technology in order to optimize the trade-off between image quality and dose. The goal of this study was to characterize the EOS system in terms of occupational exposure, organ doses to patients as well as image quality for full spine examinations. Methods: Occupational exposure was determined by measuring the ambient dose equivalents in the radiological room during a standard full spine examination. The patient dosimetry was performed using anthropomorphic phantoms representing an adolescent and a five-year-old child. The organ doses were measured with thermoluminescent detectors and then used to calculate effective doses. Patient exposure with EOS was then compared to dose levels reported for conventional radiological systems. Image quality was assessed in terms of spatial resolution and different noise contributions to evaluate the detector's performances of the system. The spatial-frequency signal transfer efficiency of the imaging system was quantified by the detective quantum efficiency (DQE). Results: The use of a protective apron when the medical staff or parents have to stand near to the cubicle in the radiological room is recommended. The estimated effective dose to patients undergoing a full spine examination with the EOS system was 290μSv for an adult and 200 μSv for a child. MTF and NPS are nonisotropic, with higher values in the scanning direction; they are in addition energy-dependent, but scanning speed independent. The system was shown to be quantum-limited, with a maximum DQE of 13%. The relevance of the DQE for slot-scanning system has been addressed. Conclusions: As a summary, the estimated effective dose was 290μSv for an adult; the image quality remains comparable to conventional systems.

  13. Depositional features of a late Weichselian outwash fan; central East Jylland, Denmark (United States)

    Houmark-Nielsen, Michael


    Four major sedimentary facies are present in coarse-grained, ice-marginal deposits from central East Jylland, Denmark. Facies A and B are matrix-supported gravels deposited by subaerial sediment gravity flows as mudflows (facies A) and debris flows (facies B). Facies C consists of clast-supported, water-laid gravels and facies D are cross-bedded sand and granules. The facies can be grouped into three facies associations related to the supraglacial and proglacial environments: (1) the flow-till association is made up of alternating beds of remobilized glacial mixton (facies A) and well-sorted cross-bedded sand (facies D); (2) the outwash apron association resembles the sediments of alluvial fans in containing coarse-grained debris-flow deposits (facies B), water-laid gravel deposited by sheet floods (facies C) and cross-bedded sand and granules (facies D) from braided distributaries; (3) the valley sandur association comprises water-laid gravel (facies C) interpreted as sheet bars and longitudinal bars interbedded with cross-bedded sand and granules (facies D) deposited in channels between bars in a braided environment. The general coarsening-upward trend of the sedimentary sequences caused by the transition of bars and channel-dominated facies to debris-flow-dominated facies indicate an increasing proximality of the outwash deposits, picturing the advance and still stand of a large continental lowland ice-sheet. The depositional properties suggest that sedimentation was caused by melting along a relatively steep, active glacier margin as a first step towards the final vanishing of the Late Weichselian icesheet (the East Jylland ice) covering eastern Denmark.

  14. A novel dosimeter for measuring the amount of radiation exposure of surgeons during percutaneous nephrolithotomy: Instadose™ (United States)

    Yuruk, Emrah; Gureser, Gokhan; Tuken, Murat; Ertas, Kasim


    Introduction The aim of this study was to demonstrate the efficacy of Instadose™, a novel dosimeter designed for radiation workers to provide a measurement of the radiation dose at any time from any computer; to determine the amount of radiation exposure during percutaneous nephrolithotomy (PNL); and to evaluate the factors that affect the amount of radiation exposed. Material and methods Two experienced surgeons wore Instadose™ on the outer part of their lead aprons during the PNL procedures performed between December 2013 and July 2014. Patient demographics and stone characteristics were noted. Factors affecting radiation dose were determined. Fluoroscopic screening time was compared with the amount of radiation in order to validate the measurements of Instadose™. Results Overall, 51 patients with a mean age of 43.41 ±18.58 (range 1–75) years were enrolled. Male to female ratio was 35/16. The amount of radiation was greater than 0.01mSv in only 19 (37.25%) cases. Stone location complexity (p = 0.380), dilation type (p = 0.584), stone size (p = 0.565), dilation size (p = 0.891) and access number (p = 0.268) were not associated with increased radiation exposure. Instadose™ measurements were correlated with fluoroscopic screening time (r = 0.519, p = 0.001). Conclusions Instadose™ is a useful tool for the measurement of radiation exposure during PNL. The advantage of measuring the amount of radiation exposure after each PNL operation is that it may aid urologists in taking appropriate precautions to minimize the risk of radiation related complications. PMID:27551558

  15. The crater-facies kimberlite system of Tokapal, Bastar District, Chhattisgarh, India (United States)

    Mainkar, Datta; Lehmann, Bernd; Haggerty, Stephen E.


    Discovery of diamondiferous kimberlites in the Mainpur Kimberlite Field, Raipur District, Chhattisgarh in central India, encouraged investigation of similar bodies in other parts of the Bastar craton. The earlier known Tokapal ultramafic intrusive body, located beyond the 19-km milestone in Tokapal village along the Jagdalpur-Geedam road, was reinterpreted as crater-facies kimberlite. Its stratigraphic position in the Meso-Neoproterozoic intracratonic sedimentary Indravati basin makes it one of the oldest preserved crater-facies kimberlite systems. Ground and limited subsurface data (dug-, tube-wells and exploratory boreholes) have outlined an extensive surface area (>550 ha) of the kimberlite. The morphological and surface color features of this body on enhanced satellite images suggest that there is a central feeder surrounded by a collar and wide pyroclastic apron. Exploration drilling indicates that the central zone probably corresponds to a vent overlain by resedimented volcaniclastic (epiclastic) rocks that are surrounded by a 2-km-wide spread of pyroclastic rocks (lapilli tuff, tuff/ash beds and volcaniclastic breccia). Drill-holes also reveal that kimberlitic lapilli tuffs and tuffs are sandwiched between the Kanger and Jagdalpur Formations and also form sills within the sedimentary sequence of the Indravati basin. The lapilli tuffs are commonly well stratified and display slumping. Base surges and lava flows occur in the southern part of the Tokapal system. The geochemistry and petrology of the rock correspond to average Group I kimberlite with a moderate degree of contamination. However, the exposed rock is intensely weathered and altered with strong leaching of mobile elements (Ba, Rb, Sr). Layers of vesicular fine-grained glassy material represent kimberlitic lava flows. Tuffs containing juvenile lapilli with pseudomorphed olivine macrocrysts are set in a talc-serpentine-carbonate matrix with locally abundant spinel and sphene. Garnet has not been

  16. New glacoated area in Rodna mountains-Tarnița la Cruce cirque

    Directory of Open Access Journals (Sweden)

    Marcel MÎNDRESCU


    Full Text Available Even though we refer just to one former glacial site in the Rodna mountain area, this is important from several points of view, firstly, this one was missed by previous researchers because of its lateral position from the axis of glaciation, the main ridge of the Rodna Mountains. Secondly, the cirque, with its altitude and shape,completes a population of cirques less represented in the Eastern Carpathians, compared with the Alps of Transylvania. These are called alpine cirques in the world literature, but we prefer this term of ‘Carpathian’ to fit better with the geomorphologic reality of the Romanian Carpathians. These alpine cirques have small dimensions, with apron floors where there were cold glaciers (in the ablationand accumulation areas situated inside the cirque but short ones, which ended immediately after the floor, without being continued by glacier tongues. Nowadays, after the disappearance of Quaternary glaciers, these appear hanging on the high mountain ridges (being also valley-side cirques, far from the bottom of the valleys,and have a clean aspect. Finally, this mountainous site is important and interesting, at the same time, because it is a natural mountainous environment, untouched by pollution and human influence, and very sensitive to the environmental changes. It is a ‘fresh’ glaciated site which undergoes changes because of the ending of glaciation,so any change of the environment will be sensed by its ecosystem. Therefore, this area represents a potential site for scientific research to evaluate the impact of present changes in the environment.

  17. Role of experience, leadership and individual protection in cath lab. A multicenter questionnaire and workshop on radiation safety

    Energy Technology Data Exchange (ETDEWEB)

    Kuon, E. [Klinik Fraenkische Schweiz, Ebermannstadt (Germany). Div. of Cardiology; Weitmann, K.; Hoffmann, W. [University Medicine, Greifswald (Germany). Inst. for Community Medicine; Doerr, M.; Hummel, A.; Busch, M.C.; Felix, S.B.; Empen, K. [University Medicine, Greifswald (Germany). Div. of Internal Medicine


    Radiation exposure in invasive cardiology remains considerable. We evaluated the acceptance of radiation protective devices and the role of operator experience, team leadership, and technical equipment in radiation safety efforts in the clinical routine. Cardiologists (115 from 27 centers) answered a questionnaire and documented radiation parameters for 10 coronary angiographies (CA), before and 3.1 months after a 90-min. mini-course in radiation-reducing techniques. Mini-course participants achieved significant median decreases in patient dose area products (DAP: from 26.6 to 13.0 Gy x cm{sup 2}), number of radiographic frames (- 29 %) and runs (- 18 %), radiographic DAP/frame (- 32 %), fluoroscopic DAP/s (- 39 %), and fluoroscopy time (- 16 %). Multilevel analysis revealed lower DAPs with decreasing body mass index (- 1.4 Gy x cm{sup 2} per kg/m2), age (- 1.2 Gy x cm{sup 2}/decade), female sex (- 5.9 Gy x cm{sup 2}), participation of the team leader (- 9.4 Gy x cm{sup 2}), the mini-course itself (- 16.1 Gy x cm{sup 2}), experience (- 0.7 Gy x cm{sup 2}/1000 CAs throughout the interventionalist's professional life), and use of older catheterization systems (- 6.6 Gy x cm{sup 2}). Lead protection included apron (100 %), glass sheet (95 %), lengthwise (94 %) and crosswise (69 %) undercouch sheet, collar (89 %), glasses (28 %), cover around the patients' thighs (19 %), foot switch shield (7 %), gloves (3 %), and cap (1 %). Radiation-protection devices are employed less than optimally in the clinical routine. Cardiologists with a great variety of interventional experience profited from our radiation safety workshop - to an even greater extent if the interventional team leader also participated.

  18. In situ ∼2.0 Ma trees discovered as fossil rooted stumps, lowermost Bed I, Olduvai Gorge, Tanzania. (United States)

    Habermann, Jörg M; Stanistreet, Ian G; Stollhofen, Harald; Albert, Rosa M; Bamford, Marion K; Pante, Michael C; Njau, Jackson K; Masao, Fidelis T


    The discovery of fossil rooted tree stumps in lowermost Lower Bed I from the western Olduvai Basin, Tanzania, age-bracketed by the Naabi Ignimbrite (2.038 ± 0.005 Ma) and Tuff IA (1.88 ± 0.05 Ma), provides the first direct, in situ, and to date oldest evidence of living trees at Olduvai Gorge. The tree relicts occur in an interval dominated by low-viscosity mass flow and braided fluvial sediments, deposited at the toe of a largely Ngorongoro Volcano-sourced volcaniclastic fan apron that comprised a widely spaced network of ephemeral braided streams draining northward into the Olduvai Basin. Preservation of the trees occurred through their engulfment by mass flows, post-mortem mold formation resulting from differential decay of woody tissues, and subsequent fluvially-related sediment infill, calcite precipitation, and cast formation. Rhizolith preservation was triggered by the interaction of root-induced organic and inorganic processes to form rhizocretionary calcareous root casts. Phytolith analyses were carried out to complete the paleoenvironmental reconstruction. They imply a pronounced seasonality and indicate a wooded landscape with grasses, shrubs, and sedges growing nearby, comparable to the low, open riverine woodland (unit 4c) along the Garusi River and tributaries in the Laetoli area. Among the tree stump cluster were found outsized lithic clasts and those consisting of quartzite were identified as Oldowan stone tool artifacts. In the context of hominin activity, the identification of wooded grassland in association with nearby freshwater drainages and Oldowan artifacts significantly extends our paleoenvironmental purview on the basal parts of Lower Bed I, and highlights the hitherto underrated role of the yet poorly explored western Olduvai Gorge area as a potential ecologically attractive setting and habitat for early hominins.

  19. The stratigraphy of cretaceous mudstones in the eastern Fuegian Andes: new data from body and trace fossils

    Directory of Open Access Journals (Sweden)

    Eduardo B. Olivero


    Full Text Available The stratigraphy of Cretaceous marine mudstones in the Fuegian Andes, roughly equivalent to Charles Darwin's clay-slate formation, remains a still unsolved problem. Previous records of Albian, Turonian-Coniacian, and Santonian-Campanian bivalves are combined with new findings of the Late Albian inoceramid Inoceramus anglicus Woods, and the Maastrichtian ammonites Diplomoceras sp., Anagaudryceras sp., Maorites densicostatus (Kilian and Reboul, Maorites sp., and Pachydiscus (Neodesmoceras sp. to further constrain the Cretaceous stratigraphy of the eastern Fuegian Andes. In addition, new records of distinctive trace fossils and ichnofabric are meaningful for stratigraphic division and delineation of paleoenvironmental settings in these Cretaceous mudstones. The Lower Cretaceous ichnoassemblage of Chondrites targioni (Brongniart and Zoophycos isp. is consistent with the inferred slope-volcaniclastic apron settings of the Yahgan Formation; Nereites missouriensis (Weller reflects distal basin plain depositional settings for the Beauvoir Formation. In the Upper Cretaceous, the "Estratos de Buen Suceso" record the earliest extensively bioturbated horizons, reflecting prolonged well-oxygenated bottom conditions. In the Bahía Thetis Formation, organic-rich, channel margin or distal basin slaty mudstones record the last occurrence of inoceramid bivalves in the Austral Basin; the generalized absence of trace fossils is consistent with dysoxic bottom conditions. The thoroughly bioturbated Policarpo Formation, records a marked change in paleoceanographic conditions. The strong contrast in the intensity of bioturbation between the Upper Campanian-Maastrichtian Bahía Thetis Formation, almost devoid of trace fossils, and the highly bioturbated Maastrichtian-Danian Policarpo Formation reflects a change from dysoxic-anoxic to well ventilated conditions, probably associated with a cooling trend of bottom waters in the austral deep oceans.

  20. A study of ambient fine particles at Tianjin International Airport, China. (United States)

    Ren, Jianlin; Liu, Junjie; Li, Fei; Cao, Xiaodong; Ren, Shengxiong; Xu, Bin; Zhu, Yifang


    The total count number concentration of particles from 10 to 1000nm, particle size distribution, and PM2.5 (aerodynamic diameter≤2.5μm) mass concentration were measured on a parking apron next to the runway at Tianjin International Airport in China. The data were collected 250, 270, 300, 350, and 400m from the runway. Wind direction and wind speed played important roles in determining the characteristics of the atmospheric particles. An inverted U-shaped relationship was observed between the measured particle number concentration and wind speed, with an average peak concentration of 2.2×10(5)particles/cm(3) at wind speeds of approximately 4-5m/s. The atmospheric particle number concentration was affected mainly by aircraft takeoffs and landings, and the PM2.5 mass concentration was affected mainly by the relative humidity (RH) of the atmosphere. Ultrafine particles (UFPs, diameter<100nm), with the highest number concentration at a particle size of approximately 16nm, dominated the measured particle size distributions. The calculated particle emission index values for aircraft takeoff and landing were nearly the same, with mean values of 7.5×10(15)particles/(kg fuel) and 7.6×10(15)particles/(kg fuel), respectively. The particle emission rate for one aircraft during takeoff is two orders of magnitude higher than for all gasoline-powered passenger vehicles in Tianjin combined. The particle number concentrations remained much higher than the background concentrations even beyond 400m from the runway.

  1. Facies and facies association of the siliciclastic Brak River and carbonate Gemsbok formations in the Lower Ugab River valley, Namibia, W. Africa (United States)

    Paciullo, F. V. P.; Ribeiro, A.; Trouw, R. A. J.; Passchier, C. W.


    The Neoproterozoic Zerrissene Turbidite Complex of central-western Namibia comprises five turbiditic units. From the base to the top they are the Zebrapüts Formation (greywacke and pelite), Brandberg West Formation (marble and pelite), Brak River Formation (greywacke and pelite with dropstones), Gemsbok River Formation (marble and pelite) and Amis River Formation (greywacke and pelites with rare carbonates and quartz-wacke). In the Lower Ugab River valley, five siliciclastic facies were recognised in the Brak River Formation. These are massive and laminated sandstones, classical turbidites (thick- and thin-bedded), mudrock, rare conglomerate and breccia. For the carbonate Gemsbok River Formation four facies were identified including massive non-graded and graded calcarenite, fine grained evenly bedded blue marble and calcareous mudrock. Most of these facies are also present in the other siliciclastic units of the Zerrissene Turbidite Complex as observed in other areas. The vertical facies association of the siliciclastic Brak River Formation is interpreted as representing sheet sand lobe to lobe-fringe palaeoenvironment with the abandonment of siliciclastic deposition at the top of the succession. The vertical facies association of the carbonate Gemsbok Formation is interpreted as the slope apron succession overlain by periplatform facies, suggesting a carbonate slope sedimentation of a prograding depositional shelf margin. If the siliciclastic-carbonate paired succession would represent a lowstand relative sea-level and highstand relative sea-level, respectively, the entire turbidite succession of the Zerrissene Turbidite Complex can be interpreted as three depositional sequences including two paired siliciclastic-carbonate units (Zebrapüts-Brandberg West formations; Brak River-Gemsbok formations) and an incomplete succession without carbonate at the top (Amis River Formation).

  2. Subaqueous systems fed by glacially derived hyperpycnal flows: a depositional model for Carboniferous-Permian sandstones of the Itarare Group, Parana Basin; Sistemas subaquosos alimentados por fluxos hiperpicnais glaciogenicos: modelo deposicional para arenitos do Grupo Itarare, Permocarbonifero da Bacia do Parana

    Energy Technology Data Exchange (ETDEWEB)

    Vesely, Fernando Farias [PETROBRAS, Rio de Janeiro, RJ (Brazil). E e P. Gerencia de Estratigrafia]. E-mail:


    The glacial Itarare Group constitutes the lower interval of the Carboniferous-Permian mega sequence in the Parana Basin. Thick glacially related sandstone reservoirs present in this unit contain gas and condensate sourced by Devonian marine shales. Based on outcrop data from the eastern basin margin, the sedimentary facies and stacking patterns were analyzed in order to propose a depositional model for these sandstone successions. It is suggested that the sandstones were deposited subaqueously as pro glacial fans due to melt water-derived highly concentrated hyperpycnal flows. Regional Itarare Group's stratigraphy can be expressed as several unconformity-bounded sequences deposited in a marine glaciated basin during repeated deglaciation episodes. The lower half of each sequence is constituted of thick sand-rich successions typically showing fining-upward and a retrogradational stacking pattern. Eleven facies were recognized, ranging from conglomerates to fine-grained sandstones, massive, graded or stratified. Conglomerates and cross-bedded coarse sandstones represent proximal Subaqueous deposits and were formed as ice-contact out wash fans/aprons due to melt water-derived hyper concentrated and concentrated flows and traction dominated bottom currents. These flows served as feeder systems to stratified, massive or graded turbiditic sandstone lobes deposited more distally. Parallel bedding and climbing ripples present in these beds were formed due to continuous aggradation from waxing and/or waning long-lived turbidity currents. These characteristics typify hyperpycnites and suggest that melt water derived hyperpycnal flows were the main trigger mechanisms to turbidity currents in the Itarare Group. (author)

  3. SU-E-P-20: Personnel Lead Apparel Integrity Inspection: Where We Are and What We Need?

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S; Zhang, J; Anaskevich, L; Oates, E [University of Kentucky, Lexington, KY (United States)


    Purpose: In recent years, tremendous efforts have been devoted to radiation dose reduction, especially for patients who are directly exposed to primary radiation or receive radiopharmaceuticals. Limited efforts have been focused on those personnel who are exposed to secondary radiation while fulfilling their work responsibilities associated with diagnostic imaging and image-guided interventions. Occupational exposure is compounded in daily practice and can lead to a significant radiation dose over time. Personnel lead apparel is a well-accepted engineering control to protect healthcare workers when radiation is inevitable. The question is, do we have a nationally established program to protect personnel? This study is to investigate the lead apparel inspection programs among the USA. Methods: A series of surveys of state regulations, the University Health System Consortium, and federal regulations and regulations determined by accrediting bodies were conducted. The surveys were used to determine the current status of lead apparel programs regarding integrity inspections. Based on the survey results, a thorough program was proposed accordingly. Results: Of 50 states, seventeen states and Washington D.C. require lead apparel integrity inspections within their state regulations. Eleven of these states specify that the inspection is required on an annual basis. Two of these states require lead apron integrity checks to be performed semi-annually. Eleven out of the two hundred academic medical centers surveyed responded. The results show that the method (visually vs. fluoroscopy) used to conduct lead apparel integrity checks differ greatly amongst healthcare organizations. The FDA, EPA, CRCPD and NCRP require lead apparel integrity checks. However, the level of policies is different. A standard program is not well established and clearly there is a lack of standardization. Conclusion: A program led by legislative (state or federal government) and with specific frequency

  4. Features of Female Clothing and Their Cultural Causes of Ethnic Yao in Yun 'nan%湖南瑶族女性的服饰特征及其文化成因

    Institute of Scientific and Technical Information of China (English)

    肖宇强; 肖琼琼


    Ethnic Yao has originated and been staying in Hu'nan. Though they are descendants of the same ancestor, female clothing displays different styles and features. Female Yao living in mountains like to wear brocades, circumference hats and plain dresses, while Yao wearing huge shelving are of great imposing manner. Yao living on flat grounds wear headcloth, indigo clothes and patterned aprons, while Yao wearing colorful hats like to wear colorful ribbons, and cross-switch tight skirts. The cultural differences of these clothes are caused by local climate, ecology, national traditions and believes, propitious connotations and influences from advanced culture.%瑶族自古以来就长期生息于湖南境内,虽起源于同一祖先,但是分布于湖南各地区的瑶族女性服饰却呈现出迥然不同的风格与特征:高山瑶女性披织锦、戴围帽,服饰简洁素雅;顶板瑶女性头顶"大排架",气势庞大;平地瑶女性裹包头巾、穿青蓝衣、花围裙,朴实平和;花瑶女性戴花帽、缠五色丝带、着挑花筒裙,华丽多姿.这些服饰的文化成因主要受到当地生态气候环境、民族传统信仰、吉祥寓意观念和外来先进文化的影响,展现了我国少数民族独特的审美情趣、工艺技巧和文化内涵.

  5. Measurementof photo-neutron dose from an 18-MV medical linac using a foil activation method in view of radiation protection of patients

    Energy Technology Data Exchange (ETDEWEB)

    Yuecel, Haluk; Kolbasi, Asuman; Yueksel, Alptug Oezer [Ankara University, Institute of Nuclear Sciences, Ankara (Turkmenistan); Cobanbas, Ibrahim; Kaya, Vildan [Sueleyman Demirel University, School of Medicine, Dept. of Radiation Oncology, Isparta (Turkmenistan)


    High-energy linear accelerators are increasingly used in the medical field. However, the unwanted photo-neutrons can also be contributed to the dose delivered to the patients during their treatments. In this study, neutron fluxes were measured in a solid water phantom placed at the isocenter 1-m distance from the head of an 18-MV linac using the foil activation method. The produced activities were measured with a calibrated well-type Ge detector. From the measured fluxes, the total neutron fluence was found to be (1.17 ± 0.06) X 10{sup 7} n/cm{sup 2} per Gy at the phantom surface in a 20 X 20 cm{sup 2} X-ray field size. The maximum photo-neutron dose was measured to be 0.67 ± 0.04 mSv/Gy at d{sub max} = 5 cm depth in the phantom at isocenter. The present results are compared with those obtained for different field sizes of 10 X 10cm{sup 2}, 15 X 15cm{sup 2}, and 20 X 20cm{sup 2} from 10-, 15-, and 18-MV linacs. Additionally, ambient neutron dose equivalents were determined at different locations in the room and they were found to be negligibly low. The results indicate that the photo-neutron dose at the patient position is not a negligible fraction of the therapeutic photon dose. Thus, there is a need for reduction of the contaminated neutron dose by taking some additional measures, for instance, neutron absorbing-protective materials might be used as aprons during the treatment.

  6. Causes and mobility of large volcanic landslides: application to Tenerife, Canary Islands (United States)

    Hürlimann, M.; Garcia-Piera, J. O.; Ledesma, A.


    Giant volcanic landslides are one of the most hazardous geological processes due to their volume and velocity. Since the 1980 eruption and associated debris avalanche of Mount St. Helens hundreds of similar events have been recognised worldwide both on continental volcanoes and volcanic oceanic islands. However, the causes and mobility of these enormous mass movements remain unresolved. Tenerife exhibits three voluminous subaerial valleys and a wide offshore apron of landslide debris produced by recurrent flank failures with ages ranging from Upper Pliocene to Middle Pleistocene. We have selected the La Orotava landslide for analysis of its causes and mobility using a variety of simple numerical models. First, the causes of the landslide have been evaluated using Limit Equilibrium Method and 2D Finite Difference techniques. Conventional parameters including hydrostatic pore pressure and material strength properties, together with three external processes, dike intrusion, caldera collapse and seismicity, have been incorporated into the stability models. The results indicate that each of the external mechanism studied is capable of initiating slope failures. However, we propose that a combination of these processes may be the most probable cause for giant volcanic landslides. Second, we have analysed the runout distance of the landslide using a simple model treating both the subaerial and submarine parts of the sliding path. The effect of the friction coefficient, drag forces and hydroplaning has been incorporated into the model. The results indicate that hydroplaning particularly can significantly increase the mobility of the landslide, which may reach runout distances greater than 70 km. The models presented are not considered definite and have mainly a conceptual purpose. However, they provide a physical basis from which to better interpret these complex geologic phenomena and should be taken into account in the prediction of future events and the assessment of

  7. Geomorphology and sedimentary features, and temporal component-change of lahar deposits at the northern foot of Chokai volcano, NE Japan (United States)

    Minami, Y.; Ohba, T.; Kataoka, K.; Hayashi, S.


    Chokai volcano is an andesitic stratovolcano that collapsed to the north ca.2500 years ago. The post-collapse fan deposits are distributed in the northern foot of the volcano, and to reveal their depositional process in terms of modern sedimentology, we carried out the geological study includung digging survey, as well as geomorphological analysis, mineralogy, and 14C chronology. Consequently, the geological study revealed that the fan deposits consist of more than 16 units, which are debris flow, hyperconcentrated flow and streamflow deposits. We give hare general name lahar deposits for these deposits. The lahar deposits have a total thickness of 30 m, and overlie the 2.5-ka Kisakata debris avalanche deposit. The lahar deposits form a part of volcanic fan and volcaniclastic apron of Chokai volcano. In proximal areas (steep or moderate sloped areas), the lahar flowed down as debris flows, and in the distal area (horizontal area) the lahars transformed into hyperconcentrated flow or stream flows but partly arrived the area as debris flow. The hyperconcentrated flows or stream flows reached the horizontal area at least four times, supposed by AMS dating (the ages of some lahar deposits are 2200, 1500-1600, 1000-1200, and 100-200 yBP). The lahar deposits contain clasts of altered andesite, fresh andesite, mudstone and sandstone. Proportions of altered andesite clasts to total clasts decrease upwards in stratigraphic sequence. Matrices of the lower eight units are composed of grayish-blue clay, and are different from those of the upper eight units, composed of brownish yellow volcanic sand. The stratigraphic variation in matrix component is consistent with the change in matrix mineral assemblage, possibly reflecting changes in the source materials from Chokai volcano.

  8. Reconstruction of hazard-related geomorphic events from mixed-volcanoclastic sequences in the Campanian coastal area (Eastern Tyrrhenian Sea) (United States)

    Violante, Crescenzo; Esposito, Eliana; Molisso, Flavia; Porfido, Sabina; Sacchi, Marco


    Sudden emplacement of large amount of pyroclastic material from explosive eruptions represents a significant interference with the geomorphic system, both for inland and coastal areas. Large volcanocalstic activity can induce sediment overburden and consequent return to the equilibrium profile by means of land degradation and erosional processes. Volcaniclastic resedimentation and generation of mass flows and floods are common phenomena affecting wide areas near the volcanic vents, occurring either soon after volcanic eruptions and during inter-eruption periods. In volcanic coastal areas volcanic debris can enter the sea in the form of avalanche deposits, hyper-concentrated flows or as the underwater continuation of subaerial flows and surges. Rapid accumulation at sea of tephra deposits from explosive eruptions can led to seafloor failure or act as weak layers for successive gravity deformations. Yet, part of volcaniclastic material can be stored in the catchments and be available for erosion a long time after an eruption. In the study area sediment availability strictly relate to massive and intermittent volcaniclastic delivery, largely responsible for aggradation/progradation of the coastal area during the Quaternary. The discussed hazard-related sedimentary features include large aprons of avalanche deposits off volcanic structures, steep sedimentary progradations at mouth of bedrock streams and small rivers, sediment re-mobilization in pro-delta areas, and shallow slides. Marine geophysical surveys and sea-land correlations led to associate such features with volcanic processes including the Mt. Epomeo uplift at Ischia island, the collapse of the Somma-Vesuvius caldera and the emplacement of pyroclastics from Phlegrean Fields and Somma-Vesuvius.

  9. Development and relationship of monogenetic and polygenetic volcanic fields in time and space. (United States)

    Germa, Aurelie; Connor, Chuck; Connor, Laura; Malservisi, Rocco


    The classification of volcanic systems, developed by G. P. L. Walker and colleagues, relates volcano morphology to magma transport and eruption processes. In general, distributed monogenetic volcanic fields are characterized by infrequent eruptions, low average output rate, and a low spatial intensity of the eruptive vents. In contrast, central-vent-dominated systems, such as stratovolcanoes, central volcanoes and lava shields are characterized by frequent eruptions, higher average flux rates, and higher spatial intensity of eruptive vents. However, it has been observed that a stratovolcano is often associated to parasitic monogenetic vents on its flanks, related to the central silicic systems, and surrounded by an apron of monogenetic edifices that are part of the volcanic field but independent from the principal central system. It appears from spatial distribution and time-volume relationships that surface area of monogenetic fields reflects the lateral extent of the magma source region and the lack of magma focusing mechanisms. In contrast, magma is focused through a unique conduit system for polygenetic volcanoes, provided by a thermally and mechanically favorable pathway toward the surface that is maintained by frequent and favorable stress conditions. We plan to relate surface observations of spatio-temporal location of eruptive vents and evolution of the field area through time to processes that control magma focusing during ascent and storage in the crust. We choose to study fields that range from dispersed to central-vent dominated, through transitional fields (central felsic system with peripheral field of monogenetic vents independent from the rhyolitic system). We investigate different well-studied volcanic fields in the Western US and Western Europe in order to assess influence of the geodynamic setting and tectonic stress on the spatial distribution of magmatism. In summary, incremental spatial intensity maps should reveal how fast a central conduit

  10. Mesozoic architecture of a tract of the European-Iberian continental margin: Insights from preserved submarine palaeotopography in the Longobucco Basin (Calabria, Southern Italy) (United States)

    Santantonio, Massimo; Fabbi, Simone; Aldega, Luca


    The sedimentary successions exposed in northeast Calabria document the Jurassic-Early Cretaceous tectonic-sedimentary evolution of a former segment of the European-Iberian continental margin. They are juxtaposed today to units representing the deformation of the African and Adriatic plates margins as a product of Apenninic crustal shortening. A complex pattern of unconformities reveals a multi-stage tectonic evolution during the Early Jurassic, which affected the facies and geometries of siliciclastic and carbonate successions deposited in syn- and post-rift environments ranging from fluvial to deep marine. Late Sinemurian/Early Pliensbachian normal faulting resulted in exposure of the Hercynian basement at the sea-floor, which was onlapped by marine basin-fill units. Shallow-water carbonate aprons and reefs developed in response to the production of new accommodation space, fringing the newborn islands which represent structural highs made of Paleozoic crystalline and metamorphic rock. Their drowning and fragmentation in the Toarcian led to the development of thin caps of Rosso Ammonitico facies. Coeval to these deposits, a thick (> 1 km) hemipelagic/siliciclastic succession was sedimented in neighboring hanging wall basins, which would ultimately merge with the structural high successions. Footwall blocks of the Early Jurassic rift, made of Paleozoic basement and basin-margin border faults with their onlapping basin-fill formations, are found today at the hanging wall of Miocene thrusts, overlying younger (Middle/Late Jurassic to Late Paleogene) folded basinal sediments. This paper makes use of selected case examples to describe the richly diverse set of features, ranging from paleontology to sedimentology, to structural geology, which are associated with the field identification of basin-margin unconformities. Our data provide key constraints for restoring the pre-orogenic architecture of a continental margin facing a branch of the Liguria-Piedmont ocean in the

  11. SU-E-P-46: Clinical Acceptance Testing and Implementation of a Portable CT Unit

    Energy Technology Data Exchange (ETDEWEB)

    LaFrance, M; Marsh, S; Hicks, R; O’Donnell-Moran, G [Baystate Health Systems, Inc., Springfield, MA (United States)


    Purpose: Planning for the first installation in New England of a new portable CT unit to be used in the Operating Room required the integration of many departments including Surgery, Neurosurgery, Information Services, Clinical Engineering, Radiology and Medical Physics/Radiation Safety. Acceptance testing and the quality assurance procedures were designed to optimize image quality and patient and personnel radiation exposure. Methods: The vendor’s protocols were tested using the CT Dosimetry phantoms. The system displayed the CTDIw instead of the CTDIvol while testing the unit. Radiation exposure was compared to existing CT scanners from installed CT units throughout the facility. Brainlab measures all 4 periphery slots on the CT Dosimetry phantom. The ACR measures only the superior slot for the periphery measurement. A comprehensive radiation survey was also performed for several locations. Results: The CTDIvol measurements were comparable for the following studies: brain, C-Spine, and sinuses. However, the mobile CT measurements were slightly higher than other CT units but within acceptable tolerance if measured using the ACR method.Based on scatter measurements, it was determined if any personnel were to stay in the OR Suite during image acquisition that the appropriate lead apron and thyroid shields had to be worn.In addition, to reduce unnecessary scatter, there were two mobile 6 foot wide shields (1/16″ lead equivalent) available to protect personnel in the room and adjacent areas. Conclusion: Intraoperative CT provides the physician new opportunities for evaluation of the progression of surgical resections and device placement at the cost of increasing the amount of trained personnel required to perform this procedure. It also brings with it challenges to keep the radiation exposure to the patients and staff within reasonable limits.

  12. Obesidad mórbida: caso excepcional de reconstrucción de pared abdominal Morbid obesity: an exceptional patient. Apronectomy and new abdominal wall reconstruction

    Directory of Open Access Journals (Sweden)

    F.J. Gabilondo Zubizarreta


    Full Text Available Presentamos una nueva técnica para la reconstrucción de la pared abdominal, con material sintético en una paciente que padeciendo un cuadro de obesidad mórbida sin cirugía ni traumatismo previo, sufre una diástasis de músculos rectos de su pared abdominal por la que se produce una evisceración intestinal que al alojarse en el faldón abdominal y añadirse un proceso de acumulación de líquidos en el intersticio semejante al linfedema, supuso como tratamiento una resección superior a los 60 Kg. entre sólidos y líquidos y una estrategia y técnica nuevas de reconstrucción del defecto de la pared abdominal.The aim of this work is to show a new technique for reconstruction of the abdominal wall with synthetic matherial in a patient with morbid obesity. The disease has no relation with antecedents of previous surgery or trauma and is asociated with a dyasthasis of the rectus abdomini muscles which has conditionated a intestinal evisceration.This evisceration is accommodated in the abdominal apron and is associated with a great accumulation of fluid (liquid in the interstitium, which seems a linphedema. Taking account the combination of liquid and soft tissues the resection is larger than 60 Kg. and this has forced us to develop new strategies for the menagement of the patient and techniques for the reconstruction of the abdominal wall defect.

  13. Facies analysis of an ancient, dismembered, large caldera complex and implications for intra-arc subsidence: Middle Jurassic strata of Cobre Ridge, southern Arizona, USA (United States)

    Riggs, Nancy R.; Busby-Spera, Cathy J.


    The Middle Jurassic (˜ 170 Ma) Cobre Ridge caldera is an elongate caldera complex that formed during the eruption of the tuff of Pajarito, a crystal-rich rhyodacite ignimbrite with an estimated volume > 1000 km 3. The caldera subsided in two subequal blocks: to the southeast, caldera-forming ignimbrite is as much as 3000 m thick, whereas the northwest half of the caldera subsided to lesser depths during the initial eruption, but was the locus of subsidence during subsequent eruptions, providing a depocenter for a > 1.5 km-thick section of secondary- and post-collapse volcanic and sedimentary strata. These strata record moat formation and filling and waning volcanism, including: (1) areally restricted ignimbrites up to several tens of meters thick that may have been ponded between caldera margins and/or fault scarps; (2) a ⩾ 600 m-thick ignimbrite whose eruption probably caused further collapse of the caldera or enlargement of the caldera margins; (3) a localized debris apron deposit up to 500 m thick that represents material reworked from intra-caldera pyroclastic deposits and possibly caldera walls; and (4) eolian and fluvial sandstones and water-lain tuffs. Megabreccia blocks as large as 0.5 km along strike probably demarcate approximate caldera margins, suggesting that the composite caldera was approximately 50 km long by 25 km wide. The preserved thickness of the strata of Cobre Ridge ( > 4500 m) is greater than many ancient continental volcanic sequences, suggesting external (i.e. tectonic) controls on subsidence, but preservation of this great thickness of strata is apparently due entirely to volcanic subsidence.

  14. Dynamic paleogeography of the Jurassic Andean Basin: pattern of transgression and localisation of main straits through the magmatic arc

    Directory of Open Access Journals (Sweden)

    J-C. Vicente


    Full Text Available The paleogeographic evolution of the Jurassic Andean retroarc basin is examined at a global scale for the Central Andes. In this paper, it is called for the striking continuity and lasting of the active volcanic arc. Both direct and indirect sedimentologic evidences allow to locate the western border (insular of the basin and opposite it with the eastern border (cratonic. Emphasis is placed on the volcaniclastic deposits and synsedimentary structures associated with this insular border. It is concluded that the arc magmatic activity has contributed considerably in sediment supply to the basin. Extent and continuity of the arc implies to locate the straits connecting with the Paleopacific. Systematic check of the time of transgressions coupled with sequential facies analysis provides a dynamic outlook of the transgressive process. Sectors with early transgression allow to distinguish two main gulfs of passage through the arc from which waters have progressed lengthwise at the same time northward and southward in a narrow retroarc furrow : the first at latitude of Taltal (25°S, the second at latitude of Curepto (35°S. Both initiated in the upper Triassic and extended during the Hettangian. The evolution as separate basins (Tarapacá and Aconcagua-Neuquén ended by fusion in middle Pliensbachian giving rise to a continuous elongated basin from Chubut to northern Peru. The remarkable continuity and narrowness of the Andean Basin leaves no doubt about its tectonic control. This stems to its geotectonic setting as a typical retroarc basin adjacent to a very active magmatic arc and explains the extreme mobility of its insular margin characterized by a huge volcanoclastic apron with associated debris flows and turbidites.

  15. Optimization of Speed Switching of BFG Booster for 350MW Power Unit%350 MW发电机组高炉煤气增压风机切换方式优化研究

    Institute of Scientific and Technical Information of China (English)

    胡捷; 娄婧鑫; 廖立


    宝钢电厂4号机组配备3台BFG增压风机,与之配套的电动机为双速电动机,可以根据BFG用量的不同进行高、低速切换运行.在实际的切换运行中,对进口调节挡板的开度范围要求十分严格,仅在1个工况点下可以进行,因此,当需要增加BFG消耗量而将低速运行的风机切换高速运行时存在BFG的放散.通过试验数据和理论分析对切换方式进行优化,找到多种切换方案并达到保证压力的稳定、减少BFG放散,实现节能的目的.%The unit 4 of Baosteel Power Plant is equipped with 3 BFG booster fans with the ancillary motor using a two-speed motor, which can switch between high and low speed according to BFG amount. In actual switching operation, the range of entrance apron was strictly required with only one operating point. Therefore, BFG would be diffused when the booster fan was switched from low speed to high speed to increase BFG consumption. Through experiment and theoretical analysis the switching mode was optimized and a variety of switching programs was designed to maintain pressure stability, reduce BFG relief and save energy.

  16. Evaluation of the enter surface dose, dose in organ and E effective dose, received by personnel and patients in studies of endoscopic retrograde cholangeopancreatography in the General Hospital of Mexico; Evaluacion de la dosis de entrada superficie, dosis en organo y dosis efectiva E, recibidas por personal y pacientes en estudios de colangiopancreatografia retrograda endoscopica en el Hospital General de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, S.; Gama T, G. [Calidad XXI SA de CV, Zacatecas 67-007 Col. Roma, 06700 Mexico D.F. (Mexico); Beristain, M.; Espino, H. [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Mexico D.F. (Mexico)]. e-mail:


    The ESD for patient and personal is measured: gastroenterologuist endoscopist G1, A1 Assistant and A2 instrumentist that carried out 22 independent therapeutic procedures of CPRE, in a fluoroscopy equipment Toshiba trademark with tube under the table, operated in automatic exposure mode, CAE to average tensions of 80 kVp. The measurement is carried out with film dosemeters of double emulsion Kodak Type 2 trademark, calibrated in terms of H{sup *} for the energy of the {sup 137} Cs, first it is determined the films sensitivity like function of the optical density DO, and second the ESD for the effective energy of the radiation beam (50 keV), in three different points from the dosemeter (C, D and H). The films was placed for the personnel in: right hand, front (eye), thyroid and thorax (under D and out F of the lead apron); in the case of the patient three positions were used: thorax, hepatic region and pelvis. The mean values of the ESD and it standard deviation SD in mGy units are determined by: study, personnel, film position in doctor and patient, dosemeter measurement point. The calculated doses in organ are also determined for the patient in the thorax region, liverwort and pelvis its are agreement with the NRPB SR 262 report. Finally the H{sub E} and E for medical personnel and patients are estimated demonstrating that its are not exceeded the annual dose limits for the case of the OEP. In the case of the the OEP have for the D thorax an ESD{sub max} = 0.04 mGy that one corresponds an H{sub E} = 0.02 and E = 0.01 mSv. (Author)

  17. Use of personal protective equipment under occupational exposure to cytostatics

    Directory of Open Access Journals (Sweden)

    Sylwia Krzemińska


    Full Text Available Background: A growing number of cancer cases enhances the usage of cytostatic agents and thereby contributes to the increase in the number of health care workers occupationally exposed to cytostatics. Material and Methods: This article presents the results of the survey aimed at obtaining data on the reduction of occupational exposure through using personal protective equipment by the medical and pharmaceutical personnel involved in handling cytostatics. The questionnaires were sent by mail or e-mail to oncology hospitals and pharmacies preparing cytostatic drugs. Responses were received from 94 people employed in these workplaces. The main questions concerned the forms of cytostatics; job activities; types of personal protective equipment used and working time under exposure to cytotoxic drugs. Results: The majority (over 90% of the healthcare personnel declared the use of personal protective equipment when working under conditions of exposure to cytostatic drugs. Depending on the type of protection, 15–35% of people reported that the most frequent time of their single use of the apron, the overalls, the gloves, the cap, the goggles or the respirators did not exceed few minutes. Gloves were changed most frequently. However, half of the responses indicated that the time after which the respondents removed protection equipment greatly differed. Conclusions: Almost the whole group of respondents applied personal protective equipment when working under exposure to cytostatics. However, personal protective equipment was not used every time in case of exposure. The medical and pharmaceutical staff worked under exposure to cytostatics for a few or even dozen hours during the working day. Med Pr 2016;67(4:499–508

  18. Dis-appearance and dys-appearance anew: living with excess skin and intestinal changes following weight loss surgery. (United States)

    Groven, Karen Synne; Råheim, Målfrid; Engelsrud, Gunn


    The aim of this article is to explore bodily changes following weight loss surgery. Our empirical material is based on individual interviews with 22 Norwegian women. To further analyze their experiences, we build primarily on the phenomenologist Drew Leder`s distinction between bodily dis-appearance and dys-appearance. Additionally, our analysis is inspired by Simone de Beauvoir, Merleau-Ponty and Julia Kristeva. Although these scholars have not directed their attention to obesity operations, they occupy a prime framework for shedding light on different dimensions of bodily change. In doing so, we were able to identify two main themes: The felt "inner" body versus the visible "surface" body and the "old" body versus the "new" body. In different, though interconnected ways, these main themes encompass tensions between changes the women experienced as contributing to a more "normal" and active life, feeling more accepted, and changes that generated ambivalence. In particular, their skin became increasingly problematic because it did not "shrink" like the rest of the body. On the contrary, it became looser and looser. Moreover, badsmelling folds of skin that wobbled, sweated and chafed at the smallest movement, aprons of fat hanging in front of their stomachs, batwing arms, thick flabby thighs and sagging breasts were described as a huge contrast to the positive response they received to their changed body shape when they were out and about with their clothes on. At the same time, they expressed ambivalence with regards to removing the excess skin by means of plastic surgery. Through their own and other women`s experiences they learned removing the excess skin by means of surgery could be a double-edged sword. By illuminating the experiences of the ones undergoing such changes our article offers new insight in a scholarly debate predominated by medical research documenting the positive outcomes of weight loss surgery.

  19. Solid cancer incidence among Chinese medical diagnostic x-ray workers, 1950-1995: Estimation of radiation-related risks. (United States)

    Sun, Zhijuan; Inskip, Peter D; Wang, Jixian; Kwon, Deukwoo; Zhao, Yongcheng; Zhang, Liangan; Wang, Qin; Fan, Saijun


    The objective of this study was to estimate solid cancer risk attributable to long-term, fractionated occupational exposure to low doses of ionizing radiation. Based on cancer incidence for the period 1950-1995 in a cohort of 27,011 Chinese medical diagnostic X-ray workers and a comparison cohort of 25,782 Chinese physicians who did not use X-ray equipment in their work, we used Poisson regression to fit excess relative risk (ERR) and excess absolute risk (EAR) dose-response models for incidence of all solid cancers combined. Radiation dose reconstruction was based on a previously published method that relied on simulating measurements for multiple X-ray machines, workplaces and working conditions, information about protective measures, including use of lead aprons, and work histories. The resulting model was used to estimate calendar year-specific badge dose calibrated as personal dose equivalent (Sv). To obtain calendar year-specific colon doses (Gy), we applied a standard organ conversion factor. A total of 1,643 cases of solid cancer were identified in 1.45 million person-years of follow-up. In both ERR and EAR models, a statistically significant radiation dose-response relationship was observed for solid cancers as a group. Averaged over both sexes, and using colon dose as the dose metric, the estimated ERR/Gy was 0.87 (95% CI: 0.48, 1.45), and the EAR was 22 per 10(4)PY-Gy (95% CI: 14, 32) at age 50. We obtained estimates of the ERR and EAR of solid cancers per unit dose that are compatible with those derived from other populations chronically exposed to low dose-rate occupational or environmental radiation.

  20. The Current Recommended Vitamin D Intake Guideline for Diet and Supplements During Pregnancy Is Not Adequate to Achieve Vitamin D Sufficiency for Most Pregnant Women.

    Directory of Open Access Journals (Sweden)

    Fariba Aghajafari

    Full Text Available The aims of this study were to determine if pregnant women consumed the recommended vitamin D through diet alone or through diet and supplements, and if they achieved the current reference range vitamin D status when their reported dietary intake met the current recommendations.Data and banked blood samples collected in second trimester from a subset of 537 women in the APrON (Alberta Pregnant Outcomes and Nutrition study cohort were examined. Frozen collected plasma were assayed using LC-MS/MS (liquid chromatography-tandem mass spectrometry to determine 25(OHD2, 25(OHD3, 3-epi-25(OHD3 concentrations. Dietary data were obtained from questionnaires including a Supplement Intake Questionnaire and a 24-hour recall of the previous day's diet.Participants were 87% Caucasian; mean (SD age of 31.3 (4.3; BMI 25.8 (4.7; 58% were primiparous; 90% had education beyond high school; 80% had a family income higher than CAN $70,000/year. 25(OHD2, 25(OHD3, and 3-epi-25(OHD3 were identified in all of the 537 plasma samples;3-epi-25(OHD3 contributed 5% of the total vitamin D. The median (IQR total 25(OHD (D2+D3 was 92.7 (30.4 nmol/L and 20% of women had 25(OHD concentration 75 nmol/L in some pregnant women who are residing in higher latitudes (Calgary, 51°N in Alberta, Canada and the current vitamin D recommendations for Canadian pregnant women need to be re-evaluated.

  1. Occupational exposure of apprentices in radiology in the field of professional training

    Energy Technology Data Exchange (ETDEWEB)

    Costa, R. F., E-mail: [Universidade Estadual de Goias, Unidade Universitaria de Morrinhos, Rua 14, 625, Jardim das Americas, Cep 75650-000, Morrinhos, Goias (Brazil)


    The good economic moment of our country has been providing an increase of courses in technical and technological area mainly in the field of radiology, which has raised the number of apprentices in the field of stage in clinics and hospitals. However, the shortage of placements and the fact that many of these students are workers, has forced the institutions of technical education to seek alternatives for the students to meet the workload of the stage in a time as short as possible. For this reason, often the students are obliged to comply with up to 10 hours of internship in a single day, in companies that often are not in accordance with the standards of radiological protection. What has worried the authorities of Goiania, because they believe that this exposure can raise the dose received. It is known that every person who works with X-ray diagnostics should use, during their work day and while stay in controlled area, individual dosimeter reading indirect, changed monthly. However, in practice these apprentices do not use the meter for monitoring of doses in probationary period. In This way, we measure the doses received us trainees using monitors TLDs in the thoracic region with and without plumbiferous apron on stage with total workload of 150 hours, performed daily from Monday to Friday for 6 hours per day during 5 weeks and performed to Saturday and Sunday for 10 hours daily in 7.5 weekends, with X-ray equipment conventional. The results reveal that in none of the cases the dose reached the value of 0.2 mSv, which is the minimum limit of reading dosimeter. We conclude then that the stages of weekends, taken the preventive measures of radiological protection are safe and can be performed without any prejudice with regard to the dose received, when compared to those of lower daily hourly load. (Author)

  2. Uranium mineralization in fluorine-enriched volcanic rocks

    Energy Technology Data Exchange (ETDEWEB)

    Burt, D.M.; Sheridan, M.F.; Bikun, J.; Christiansen, E.; Correa, B.; Murphy, B.; Self, S.


    Several uranium and other lithophile element deposits are located within or adjacent to small middle to late Cenozoic, fluorine-rich rhyolitic dome complexes. Examples studied include Spor Mountain, Utah (Be-U-F), the Honeycomb Hills, Utah (Be-U), the Wah Wah Mountains, Utah (U-F), and the Black Range-Sierra Cuchillo, New Mexico (Sn-Be-W-F). The formation of these and similar deposits begins with the emplacement of a rhyolitic magma, enriched in lithophile metals and complexing fluorine, that rises to a shallow crustal level, where its roof zone may become further enriched in volatiles and the ore elements. During initial explosive volcanic activity, aprons of lithicrich tuffs are erupted around the vents. These early pyroclastic deposits commonly host the mineralization, due to their initial enrichment in the lithophile elements, their permeability, and the reactivity of their foreign lithic inclusions (particularly carbonate rocks). The pyroclastics are capped and preserved by thick topaz rhyolite domes and flows that can serve as a source of heat and of additional quantities of ore elements. Devitrification, vapor-phase crystallization, or fumarolic alteration may free the ore elements from the glassy matrix and place them in a form readily leached by percolating meteoric waters. Heat from the rhyolitic sheets drives such waters through the system, generally into and up the vents and out through the early tuffs. Secondary alteration zones (K-feldspar, sericite, silica, clays, fluorite, carbonate, and zeolites) and economic mineral concentrations may form in response to this low temperature (less than 200 C) circulation. After cooling, meteoric water continues to migrate through the system, modifying the distribution and concentration of the ore elements (especially uranium).

  3. Radiation protection in interventional radiology; Strahlenschutz in der interventionellen Radiologie

    Energy Technology Data Exchange (ETDEWEB)

    Adamus, R.; Loose, R.; Galster, M. [Klinikum Nuernberg Nord, Institut fuer Diagnostische und Interventionelle Radiologie, Nuernberg (Germany); Wucherer, M. [Klinikum Nuernberg Nord, Institut fuer Medizinische Physik, Nuernberg (Germany); Uder, M. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Institut fuer Radiologie, Erlangen (Germany)


    The application of ionizing radiation in medicine seems to be a safe procedure for patients as well as for occupational exposition to personnel. The developments in interventional radiology with fluoroscopy and dose-intensive interventions require intensified radiation protection. It is recommended that all available tools should be used for this purpose. Besides the options for instruments, x-ray protection at the intervention table must be intensively practiced with lead aprons and mounted lead glass. A special focus on eye protection to prevent cataracts is also recommended. The development of cataracts might no longer be deterministic, as confirmed by new data; therefore, the International Commission on Radiological Protection (ICRP) has lowered the threshold dose value for eyes from 150 mSv/year to 20 mSv/year. Measurements show that the new values can be achieved by applying all X-ray protection measures plus lead-containing eyeglasses. (orig.) [German] Die Anwendung ionisierender Strahlung in der Medizin scheint sowohl fuer Patienten als auch fuer beruflich exponierte Personen sicher zu sein. Die interventionellen Entwicklungen der letzten Jahre mit sehr durchleuchtungs- und dosisintensiven Eingriffen erfordern allerdings eine Intensivierung des Strahlenschutzes. Es empfiehlt sich, die zur Verfuegung stehenden Moeglichkeiten auszuschoepfen. Neben den Geraeteoptionen muss der Strahlenschutz am Eingriffstisch durch Bleilamellenaufstecker und montiertes Bleiglas intensiv betrieben werden. Besonderen Fokus muss auf den Schutz der Augen zur Kataraktvermeidung gelegt werden. Da dessen Ausbildung nach neuen Erkenntnissen moeglicherweise nicht mehr deterministisch zu sehen ist, hat die Internationale Strahlenschutzkommission (IRCP) den Grenzwert von 150 auf 20 Mikrosievert (mSv)/Jahr erniedrigt. Messungen belegen, dass unter Einhaltung aller Strahlenschutzmassnahmen plus Bleiglasbrille dieser einzuhalten ist. (orig.)

  4. Effect of pregnant mare serum gonadotrophin injection on litter size in young Etawah-cross does

    Directory of Open Access Journals (Sweden)

    N.M Artiningsihi


    Full Text Available The incidence of twins and/or multiple births in 20 heads of young Etawah-cross does was studied following oestrous synchronization using intravaginal sponges containing 60 mg medroxyprogesterorle acetate (Repromap for 15 days . Twenty four hours priorto sponges withdrawal, the does were injected with pregnant mare serum gonadotrophin (PMSG at dose rates of 0 (Group A, 10 (Group B, 15 (Group C and 20 iu/kg (Group D body weight. Amature buck fitted with an apron was used to detect the onset of oestrus at every four hours. The oestrous doe was naturally mated twice, 12 hours after onset of oestrus and 10 hours later. About 3-5 days after oestrus, all does were subjected to mid-ventral laparoscopy to detect ovulation rate . Two months after mating all does were subjected to pregnancy test using diagnostic ultrasonography. Results showed that all does exhibited clear sign of oestrus. The onset of oestrus occurred 15-43 hours after sponges withdrawal or 39-59 hours after PMSG injection. Does injected with PMSG (Groups B, C and D showed oestrus 16-21 hours earlier (P0 .05 than that of control (Group A . However, there was no significant differences among the PMSG-treated groups . Ovulation rates increased from 1.0 in Group Ato 1.8 in Group B and 2.6 in bah Groups Cand D. Average litter size in Groups A, B, C and D were 1.0, 1.8, 2.4 and 1.0, respectively. It was concluded that injection of 15 iu PMSG/kg body weight gave the best result for increasing litter size in young Etawah-cross does .

  5. Study of the radiological procedures used in odontologic clinics of Boa Vista, Roraima, Brazil; Estudo dos procedimentos radiologicos nos consultorios odontologicos de Boa Vista, Roraima

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Jaberson Luiz Leitao


    The purpose of this study was to evaluate the radiological procedures used at the odontologic clinics of Boa Vista, Roraima-Brazil. The following parameters were recorded: field diameter, half value layer, total filtration, discrepancy between the preset and the applied kilovoltage and exposure time. Dose to the patient's skin from radiography of the upper molar tooth was also estimated. The results showed that 78% of the inspected units had field diameters larger than 6,0 cm, which is outside the limits recommended by the Brazilian Health Ministry. The results also showed that 14% of the equipment presented a discrepancy of more than 10% between preset and applied kilovoltage. On the other hand, the discrepancy between preset and applied exposure time is higher than 10% in 70% of the tested units. The total filtration of 77% units is lower than 1,5 mm of Al, a value recommended by the Brazilian Health Ministry for equipment that operates in the range of 50 kV to 70 kV. The survey also indicates that for 35% of the units the entrance dose in high than 3,5 mGy that is the reference value established by the Brazilian Health Ministry for dental radiography with film type. It was observed that the majority of the clinics use neither aprons nor collars for patients and that films are processed manually, without controlling temperature or processing time. Based on the results obtained it is strongly recommended that a quality control program be implemented in dental radiological clinics in Boa Vista, Roraima. (author)

  6. Terrestrial slopes in northern high latitudes: A paradigm shift regarding sediment origin, composition, and dynamic evolution (United States)

    Lønne, Ida


    High-Arctic terrestrial slopes have received limited systematic research interest, but increased vulnerability related to regional warming has driven the call for better knowledge of the dynamics of these systems. Studies of sediment transport from a plateau area in Adventdalen, Svalbard, and associated slopes extending to sea level demonstrate that glacial processes play a more prominent role than earlier anticipated, - especially the impact of glacial meltwater. Traces of drainage at the plateau and the dissection of the plateau edge and upper slope were clearly initiated during various stages of Late Glacial runoff. Further, there is a close association between the sediment distribution and composition at the plateau and the evolution of various types of slopes. The reconstructed sedimentation history shows that the landscape will undergo four stages with contrasting modes of sediment transport: 1) subglacial processes related to active ice, 2) processes related to the margin of active ice, 3) processes related to the melting of inactive ice, and 4) nonglacial processes. These stages form four successions, referred to as supply regimes A-D, which control the supply of water and sediments to a given slope segment. In this landscape, traces of glacial meltwater occur at most altitudes, in "odd" positions and in slope segments "without" catchments. The associated depocenters (isolated, composite or coalescing into aprons), are often outsized compared to the apparent slope catchment. Reworked glacial sediments form a significant part of the slope-debris but are covered partly or entirely by products of physical weathering. Colluvium, senso stricto, thus masks a distinct system shift related to the local termination of glacial meltwater. Consequently, the weathering part of the slope sediment budget in this region is considerably overestimated.

  7. Wave transformation across coral reefs under changing sea levels (United States)

    Harris, Daniel; Power, Hannah; Vila-Conejo, Ana; Webster, Jody


    The transformation of swell waves from deep water across reef flats is the primary process regulating energy regimes in coral reef systems. Coral reefs are effective barriers removing up to 99% of wave energy during breaking and propagation across reef flats. Consequently back-reef environments are often considered low energy with only limited sediment transport and geomorphic change during modal conditions. Coral reefs, and specifically reef flats, therefore provide important protection to tropical coastlines from coastal erosion and recession. However, changes in sea level could lead to significant changes in the dissipation of swell wave energy in coral reef systems with wave heights dependent on the depth over the reef flat. This suggests that a rise in sea level would also lead to significantly higher energy conditions exacerbating the transgressive effects of sea level rise on tropical beaches and reef islands. This study examines the potential implications of different sea level scenarios on the transformation of waves across the windward reef flats of One Tree Reef, southern Great Barrier Reef. Waves were measured on the reef flats and back-reef sand apron of One Tree Reef. A one-dimensional wave model was calibrated and used to investigate wave processes on the reef flats under different mean sea level (MSL) scenarios (present MSL, +1 m MSL, and +2 m MSL). These scenarios represent both potential future sea level states and also the paleo sea level of the late Holocene in the southern Great Barrier Reef. Wave heights were shown to increase under sea level rise, with greater wave induced orbital velocities affecting the bed under higher sea levels. In general waves were more likely to entrain and transport sediment both on the reef flat and in the back reef environment under higher sea levels which has implications for not only forecasted climate change scenarios but also for interpreting geological changes during the late Holocene when sea levels were 1

  8. The 25 September 2007 eruption of Mount Ruapehu, New Zealand: Directed ballistics, surtseyan jets, and ice-slurry lahars (United States)

    Kilgour, G.; Manville, V.; Della Pasqua, F.; Graettinger, A.; Hodgson, K. A.; Jolly, G. E.


    At 20:26 (NZDT) on 25 September 2007 a moderate gas-driven eruption beneath the summit Crater Lake of Mt. Ruapehu, New Zealand generated a directed ballistic fallout apron and surtseyan jet that impacted an area of c. 2.5 km 2 to the north of the vent. Two climbers were caught in the blast at a hut 600 m from the vent. Primary, ice-slurry lahars were generated in two catchments draining the summit region, including a flow that entered a commercial ski field. The ejecta consists of blocks of andesitic lava and scoria erupted during previous volcanic episodes, a variety of mineral-cemented lake-floor sediments, vent-fill debris and rare glassy material interpreted to be derived from a fresh batch of magma. A minority of clasts contain formerly molten elemental sulphur, indicating that vent temperatures at the base of the lake were in excess of 119 °C. The ballistic deposit is confined to a c. 40° wide swath directed northwards that extends up to 2 km from the inferred vent location beneath Crater Lake. The strong directionality of the jetted deposits and ballistic-free 'shadow-zones' sheltered by intervening topography all point to a relatively low-angle directed blast. Previous similar eruptions at Ruapehu also show preferred deposit orientations that are here correlated with an inclined and off-centre vent beneath Crater Lake. The 25 September 2007 eruption appears to have resulted from failure of a relatively shallow hydrothermal seal composed of elemental sulphur and other mineral precipitates developed in the vent breccia, which breached following overpressurization by a pulse of magmatic gases released from deeper in the conduit. This event highlights the potential hazard from relatively minor gas-driven eruptions at Ruapehu that can occur with little or no warning. Improved understanding of the eruption mechanism for this style of eruption will inform future risk assessments for Ruapehu and other similar volcanoes worldwide.

  9. Air freight in the Stockholm region with focus on Eskilstuna Airport

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    Kjell-Åke Allan Brorsson


    Full Text Available Purpose: The purpose of this article is to analyse the conditions for commencing air freight operations at the regional Eskilstuna Airport in Sweden, which require investments in airport infrastructure of at least SEK 140 –180 million. Design/ methodology: The qualitative data collection for the study was carried out through open-ended interviews with representatives of airport management, staff, representatives of residents, and actors and stakeholders in the field. In addition, much written material was collected from different authorities. Document analysis was used to systematically evaluate and review the collected documents. Content analysis was applied to organize collected data into categories. Based on the reports, decisions, environmental scanning and interviews, the data have been coded and categorized in tables via thematic analysis. Findings: The major findings of the study are that Eskilstuna Airport lacks cargo facilities and has limited apron space, and that there is strong competition from four other airports in the Stockholm region. The prospects for permanent air freight operations at Eskilstuna Airport are therefore not favourable in the current situation. However, if the development of Eskilstuna Logistics Park and the concept of inter modal highway-rail transportation are successful, they could serve as a major driving force for the development of air cargo. Furthermore, with sustainable development as a guiding principle, there is great potential to develop an airport with a high standard of environmental profile. Originality/ value: My findings are of great value to managers of airports and cargo airlines, as they highlight some of the competition aspects associated with engaging in air cargo at regional airports. The study fills a gap in existing research whose main focus is environmental issues concerning airports in general.

  10. Increased cleavage and blastocyst rate in ewes treated with bovine somatotropin 5 days before the end of progestin-based estrous synchronization. (United States)

    Montero-Pardo, A; Hernández-Cerón, J; Rojas-Maya, S; Valencia, J; Rodríguez-Cortez, A; Gutiérrez, C G


    Treatment with bovine somatotropin (bST) during estrous synchronization increased fertility and prolificacy in sheep. In the present study, a single dose of bST 5 days before the end of progestin treatment improved cleavage and embryo development. Stage of estrous cycle was synchronized in ewes (n=32) with progestin and superovulation was induced by use of FSH. Five days before the end of progestin treatment, ewes were randomly assigned to two groups: bST group (n=16) received a depot injection of 125 mg of bST sc (Lactotropina, Elanco, México) and the control group (n=16) received saline solution. Estrous was detected with rams fitted with an apron every 2 h and estrous sheep were mated every 8 h whilst in estrous. Embryos were recovered on Day 7 post mating, assessed microscopically and fixed in 4% paraformaldehyde. Cell number in blastocysts was counted after Hoechst 33342 staining. Plasma concentrations of IGF-I, insulin and progesterone were determined in eight sheep per group from the day of bST treatment to the day of embryo recovery. Cleavage rate, percentage of transferable embryos (transferable embryos/cleaved) and percentage of embryos reaching the blastocyst stage (blastocyst/cleaved) were compared between groups by logistic regression. IGF-I, insulin and progesterone plasma concentrations were analyzed by ANOVA for repeated measurements and cell number by ANOVA. Cleavage rate was greater (Psheep. Plasma concentrations of IGF-I and insulin were greater (P<0.01) in the bST-treated group. No changes were observed in progesterone concentrations (P=0.5). It is concluded that bST injection 5 days before progestin removal increases cleavage rate and the proportion of embryos that reach the blastocyst stage. These effects are associated with an increase in IGF-I and insulin concentrations.

  11. Prevalence of Salmonella in poultry processing environments in wet markets in Penang and Perlis, Malaysia

    Directory of Open Access Journals (Sweden)

    Hafiz Nidaullah


    Full Text Available Aim: The aim of this study was to determine the prevalence of various Salmonella serotypes in chickens, carcass contact surfaces as well as environmental samples collected from wet markets and small scale processing plant. Materials and Methods: A total of 182 poultry and environmental samples were collected at random on separate occasions from wet markets and small scale processing plant, during the period of October 2014 to July 2015 in Penang and Perlis, Malaysia. The samples were analyzed for the presence of Salmonella using ISO 6579:2002 conventional culture-based method. Presumptive Salmonella colonies were subjected to various biochemical tests (such as triple sugar iron and lysine iron test, serologically confirmed using polyvalent O and H antisera and further serotyped at Public Health Laboratory, Ministry of Health, Perak, Malaysia. Results: Salmonella serotypes were isolated from 161 out of 182 samples (88.46% with 100% prevalence in the whole chicken carcass and chicken cuts - as well as transport crate, cage, drum, knife, chopping board, display table, floor, bench wash water, wash water, and drain water. Salmonella was isolated from 91.67%, 83.33%, and 66.67% of defeathering machines, drain swabs, and apron, respectively. 17 serotypes were isolated in this study with Salmonella Albany (57/161, Salmonella Corvallis (42/161, and Salmonella Brancaster (37/161 being the predominant serovars. Conclusion: The most carcass contact and environmental samples collected along the wet market chicken processing line were consistently contaminated with Salmonella. This indicates that Salmonella has established itself in poultry processing environments by colonizing the surfaces of the equipment and survives in these environments by establishing biofilms. Our results highlight the need of implementing strict hygiene and sanitation standards to reduce the incidence of Salmonella. The prevalence of Salmonella in poultry can be reduced effectively

  12. Facies architecture and high-resolution sequence stratigraphy of an Upper Cretaceous platform margin succession, southern central Pyrenees, Spain (United States)

    Pomar, Luis; Gili, Eulalia; Obrador, Antonio; Ward, William C.


    Excellent exposures of Upper Cretaceous (Santonian) carbonate platforms on the northern flank of Sant Corneli anticline (southern central Pyrenees) provide detailed information of facies architecture in both depositional strike and dip directions. Basic accretional units are differentiated by facies contrast across mappable surfaces. These surfaces do not show clear evidence of subaerial erosion and are correlated basinward with bedding planes across which there are subtle changes in skeletal composition. Two types of basic accretional units have been identified based on bedding patterns, internal facies architecture and skeletal composition: (1) Rudist buildups consist of a rudist and coral belt at the platform margin, passing landward into a slender-hippuritid lithosome, locally overlain by a bioclastic blanket that passes basinward, into bioclastic "apron-like" clinobeds and into fine-grained packstone/wackestone. (2) Calcarenite wedges consist of yellow-brown, benthic-foraminifer-rich grainstones to grain-dominated packstones, with scattered rudist shells and small coral colonies, passing basinward into mud-dominated packstones to wackestones, with variable siliciclastic content (quartz sand to silt and clay). Rudist buildups and calcarenite wedges alternate, although not rhythmically. These changes in platform skeletal composition reflect changes in the dominant type of carbonate-producing biota independently of the changes in accommodation. Both types of basic accretional units: rudist buildups and calcarenite wedges, form simple sequences and parasequences according to internal lithofacies arrangement and inferred sea-level cyclicity (cycles or paracycles). High-frequency sea-level cyclicity fits in the Milankovitch frequency band. Long-term changes in accommodation governing aggradation, progradation and backstepping of basic sequences and parasequences reflect tectonic influence rather than long-term changes in eustatic sea level.

  13. Critical Role of the Neonatal Fc Receptor (FcRn) in the Pathogenic Action of Antimitochondrial Autoantibodies Synergizing with Anti-desmoglein Autoantibodies in Pemphigus Vulgaris. (United States)

    Chen, Yumay; Chernyavsky, Alex; Webber, Robert J; Grando, Sergei A; Wang, Ping H


    Pemphigus vulgaris (PV) is a life-long, potentially fatal IgG autoantibody-mediated blistering disease targeting mucocutaneous keratinocytes (KCs). PV patients develop pathogenic anti-desmoglein (Dsg) 3 ± 1 and antimitochondrial antibodies (AMA), but it remained unknown whether and how AMA enter KCs and why other cell types are not affected in PV. Therefore, we sought to elucidate mechanisms of cell entry, trafficking, and pathogenic action of AMA in PV. We found that PVIgGs associated with neonatal Fc receptor (FcRn) on the cell membrane, and the PVIgG-FcRn complexes entered KCs and reached mitochondria where they dissociated. The liberated AMA altered mitochondrial membrane potential, respiration, and ATP production and induced cytochrome c release, although the lack or inactivation of FcRn abolished the ability of PVIgG to reach and damage mitochondria and to cause detachment of KCs. The assays of mitochondrial functions and keratinocyte adhesion demonstrated that although the pathobiological effects of AMA on KCs are reversible, they become irreversible, leading to epidermal blistering (acantholysis), when AMA synergize with anti-Dsg antibodies. Thus, it appears that AMA enter a keratinocyte in a complex with FcRn, become liberated from the endosome in the cytosol, and are trafficked to the mitochondria, wherein they trigger pro-apoptotic events leading to shrinkage of basal KCs uniquely expressing FcRn in epidermis. During recovery, KCs extend their cytoplasmic aprons toward neighboring cells, but anti-Dsg antibodies prevent assembly of nascent desmosomes due to steric hindrance, thus rendering acantholysis irreversible. In conclusion, FcRn is a common acceptor protein for internalization of AMA and, perhaps, for PV autoantibodies to other intracellular antigens, and PV is a novel disease paradigm for investigating and elucidating the role of FcRn in this autoimmune disease and possibly other autoimmune diseases.

  14. Atlantic and indian oceans pollution in africa (United States)

    Abubakar, Babagana

    Africa is the second largest and most populated continent after Asia. Geographically it is located between the Atlantic and Indian Oceans. Most of the Africa's most populated and industrialized cities are located along the coast of the continent facing the Atlantic and Indian Oceans, example of such cities include Casablanca, Dakar, Accra, Lagos, Luanda and Cape town all facing the Atlantic Ocean and cities like East London, Durban, Maputo, Dar-es-salaam and Mogadishu are all facing the Indian Ocean. As a result of the geographical locations of African Coastal Cities plus increase in their population, industries, sea port operations, petroleum exploration activities, trafficking of toxic wastes and improper waste management culture lead to the incessant increase in the pollution of the two oceans. NATURE OF POLLUTION OF THE ATLANTIC OCEAN i. The petroleum exploration activities going on along the coast of "Gulf of Guinea" region and Angola continuously causes oil spillages in the process of drilling, bunkering and discharging of petroleum products in the Atlantic Ocean. ii. The incessant degreasing of the Sea Ports "Quay Aprons" along the Coastal cities of Lagos, Luanda, Cape Town etc are continuously polluting the Atlantic Ocean with chemicals. iii. Local wastes generated from the houses located in the coastal cities are always finding their ways into the Atlantic Ocean. NATURE OF POLLUTION OF THE INDIAN OCEAN i. Unlike the Atlantic ocean where petroleum is the major pollutant, the Indian Ocean is polluted by Toxic / Radioactive waste suspected to have been coming from the developed nations as reported by the United Nations Environmental Programme after the Tsunami disaster in December 2004 especially along the coast of Somalia. ii. The degreasing of the Quay Aprons at Port Elizabeth, Maputo, Dar-es-Salaam and Mongolism Sea Ports are also another major source polluting the Indian Ocean. PROBLEMS GENERATED AS A RESULT OF THE OCEANS POLLUTION i. Recent report

  15. The volcanotectonic structures of Ascraeus Mons (United States)

    Byrne, Paul; van Wyk de Vries, Benjamin; Murray, John; Troll, Valentin


    Ascraeus Mons is the tallest of three large volcanoes situated to the NE of the Tharsis Rise and aligned parallel to a NE-SW regional structural trend. With a vertical relief of 14.9 km and an E-W diameter of 400 km, the main shield has a convex-upward morphology and a summit plateau, whilst significantly younger lava rift aprons issue from expansive embayments on its lower flanks onto the surrounding plains. The volcano hosts several types of well-preserved surface structures, and so has served as a basis for understanding Martian volcano geodynamics. Previous studies have not incorporated the full set of structures on Ascraeus Mons, however, and have been limited by photogeological data of lower resolution than that available today. We have used a GIS of MOLA, HRSC, and CTX data to map the spatial and temporal distributions of the most pronounced structures on Ascraeus Mons — its summit calderas, flank terraces, arcuate graben, and pit craters — to develop as comprehensive an evolutionary sequence for this volcano as possible. We summarise our mapping results here. · The 55-km wide caldera complex consists of at least three NE-SW-aligned depressions, with a possible fourth caldera on the periphery. Depths range from 818 m for the shallowest caldera to 3,110 m for the deepest. Whilst most lavas on the volcano are summit-derived, even the latest flows are cut by post-caldera formation subsidence and fracturing. · Flank terraces, topographically subtle outward-verging, convex-upward structures, encircle Ascraeus Mons in an imbricate, fish-scale pattern. 142 terraces in total extend from immediately below the summit to the basal plains, but do not occur on the rift aprons. The mean circumferential length for terraces is 31.9 km, though terraces over 60 km long lie on the NW and SE flanks. · Arcuate graben crosscut the NW flanks and surrounding plains, and extend for ca. 90° concentric to the volcano. These structures vary in width from 400 m to 1,200 m, and

  16. Estratigrafía, facies y evolución depositacional de la Formación Sauce Grande (Carbonífero Superior: Cuenca Sauce Grande, Sierras Australes, Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    R. R. Andreis


    waques (Smw representan flujos de detritos finos y densos transicionales a flujos licuefactos. Las demás areniscas representan acción de oleaje o corrientes (Sr o por acreción frontal en barras transversales o dunas de arena por flujos traccionales (Sp. El comienzo de los procesos depositacionales de la Formación Sauce Grande fue caracterizado por una rápida transgresión en el Carbonífero tardío bajo condiciones de moderada subsidencia (procesos eustáticos. El megaciclo inferior se caracteriza por la sedimentación en un slope apron o debris apron localizado en las cercanías del talud continental, con fuerte agradación y rara progradación y depende del régimen termal de la base de los glaciares africanos de base fría, bajo condiciones de sistema de mar bajo. En el megaciclo medio significa una rápida fase de avance glaciar asociada a somerización isostática y el tope del apron habría sido retrabajado por olas y corrientes, creando una plataforma costa afuera casi emergente. En el megaciclo superior se produce un nuevo ascenso del mar (cortejo de mar alto, asociado al retroceso de los glaciares en el sector sudafricano y produce la transgresión tastubiana que se continúa en la Formación Piedra Azul. La disminucion del aporte se hace visible por la sistemática disminución en el espesor de las facies, una mayor frecuencia de facies Dmm1 y Smw y la interacción de depósitos pelíticos, que fueron depositados en plataformas de baja pendiente donde se han registrado avance y retroceso de los glaciares. Dos glaciohorizontes fueron identificados: el GH1 vinculado al megaciclo medio y el GH2 en el contacto entre las Formaciones Sauce Grande y Piedra Azul.

  17. Surgeons' exposure to radiation in single- and multi-level minimally invasive transforaminal lumbar interbody fusion; a prospective study.

    Directory of Open Access Journals (Sweden)

    Haruki Funao

    Full Text Available Although minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF has widely been developed in patients with lumbar diseases, surgeons risk exposure to fluoroscopic radiation. However, to date, there is no studies quantifying the effective dose during MIS-TLIF procedure, and the radiation dose distribution is still unclear. In this study, the surgeons' radiation doses at 5 places on the bodies were measured and the effective doses were assessed during 31 consecutive 1- to 3-level MIS-TLIF surgeries. The operating surgeon, assisting surgeon, and radiological technologist wore thermoluminescent dosimeter on the unshielded thyroid, chest, genitals, right middle finger, and on the chest beneath a lead apron. The doses at the lens and the effective doses were also calculated. Mean fluoroscopy times were 38.7, 53.1, and 58.5 seconds for 1, 2, or 3 fusion levels, respectively. The operating surgeon's mean exposures at the lens, thyroid, chest, genitals, finger, and the chest beneath the shield, respectively, were 0.07, 0.07, 0.09, 0.14, 0.32, and 0.05 mSv in 1-level MIS-TLIF; 0.07, 0.08, 0.09, 0.18, 0.34, and 0.05 mSv in 2-level; 0.08, 0.09, 0.14, 0.15, 0.36, and 0.06 mSv in 3-level; and 0.07, 0.08, 0.10, 0.15, 0.33, and 0.05 mSv in all cases. Mean dose at the operating surgeon's right finger was significantly higher than other measurements parts (P<0.001. The operating surgeon's effective doses (0.06, 0.06, and 0.07 mSv for 1, 2, and 3 fusion levels were low, and didn't differ significantly from those of the assisting surgeon or radiological technologist. Revision MIS-TLIF was not associated with higher surgeons' radiation doses compared to primary MIS-TLIF. There were significantly higher surgeons' radiation doses in over-weight than in normal-weight patients. The surgeons' radiation exposure during MIS-TLIF was within the safe level by the International Commission on Radiological Protection's guidelines. The accumulated radiation exposure

  18. Testing modelled hillslope sediment production using a low cost sediment trap (United States)

    Borombovits, Daniel; Brooks, Andrew; Spencer, John; Pietsch, Tim; Olley, Jon


    This presentation seeks to describe the design and evaluation of a simple, low cost Hillslope Sediment Trap (HST) suitable for deployment in remote arid and semi-arid environments as detailed in a paired submission by Brooks et al. (currently under review, Catena S-13-00775 and S-13-00776). The HSTs consist of a robust, fenced enclosure from which a geofabric barrier is hung and attached to the ground, forming a wall and apron section, which is extended upslope in a U or V shape, depending on slope angle. Key considerations of the HST design include cost, ease of field transportation and construction, and low maintenance during deployment, as well as hydraulic considerations such as conductivity, effective filtration threshold for single and consecutive events, and overall sediment retention within the traps. The sediment trapping efficiency of the HSTs was tested through a series of laboratory flume experiments which showed that the traps will accurately sample the full particle size distribution of sediment mobilised on a given hillslope, with a suspended sediment (streams which drain into the Great Barrier Reef Lagoon. Using the empirical sediment yield data collected by the HSTs allowed the development of a locally calibrated hillslope erosion model, providing far more realistic predictions of erosion than have previously been employed. Total sediment yield was measured in 11 plots ranging in size from 0.1 to 1.9 ha across four main geologies in the Normanby catchment, with results ranging between 0.03 - 256 kg/ha/yr across two distinctly different wet seasons. When compared to the RUSLE modelled sediment yields determined for the same sites, plot scale metrics together provided values ranging from 1550 - 331730 kg/ha/yr. Depending on which modelled data is used, this represents an average ratio of over prediction by the RUSLE model (cf the measured rates for the same period) of between 12 to 13333 times. Reasons for the over-prediction are discussed in Brooks

  19. Angiographer's exposure to radiation under different fluoroscopic imaging conditions

    Energy Technology Data Exchange (ETDEWEB)

    Iida, Hiroji; Ueda, Shinichi; Shimizu, Mitsuru; Tamura, Sakio [Kanazawa Univ. (Japan). Hospital; Koshida, Kichiro


    Scattered radiation levels near an imaging system commonly used in angiography were measured with a 200 mm thick water phantom. The scattered radiation exposure rate was measured in lines parallel in space to the central ray of the x-ray beam, at lateral distances of 30-100 cm. The effects of an x-ray beam limiting device, geometric and electric magnification, and rotation angle of the C-arm were also determined. The results indicated that the highest scattered radiation levels occurred near the surface of the phantom where the x-ray beam enters. In P-A geometry, the highest radiation levels occurred below the angiographer's waist. These areas of the body corresponded to the gonads of the angiographer. It has been suggested that angiographers' exposure rates are higher near the gonads than near the chest. However, lead aprons efficiently protect these areas. When smaller field sizes were limited by a variable x-ray beam limiting device, the volume of irradiated tissue was reduced, and the scattered radiation exposure rate was decreased. Further, when larger magnification factors were chosen for the analogue magnification method, the volume of irradiated tissue was reduced by the automatic x-ray beam limiting device, and the scattered radiation exposure rate was decreased. However, smaller field sizes markedly increased patient exposure by auto brightness control. To mitigate the angiographer's exposure, smaller field sizes with x-ray limiting devices are required. However, a larger field size should be used whenever possible to minimize patient exposure. The angiographer's exposure rate was influenced by the incidence direction of the x-ray beam when the C-arm had been rotated around the phantom. Consequently, the angiographer's exposure rate was maximum when the x-ray tube most closely approached the angiographer and was minimum when the image intensifier most closely approached the angiographer. Therefore, to mitigate the angiographer

  20. Improved Target Segmentation Algorithm for Aircraft Parking at Airport%改进的机场停泊飞行器目标分割算法

    Institute of Scientific and Technical Information of China (English)

    陆钰; 王金根; 陈秀娟; 徐靖涛


    考虑到飞行器目标在整幅图像中所占的比例往往较小,且图像背景复杂,本文提出了一种基于机场区域提取的飞行器目标分割算法.该算法首先利用Hough变换检测直线的特性,定位机场跑道和停机坪的位置,并结合教学形态学等图像处理技术去除了非机场区域;在提取机场区域后,再选择适当的阈值对图像进行分割,最后经过形态学去噪、小区域去除等步骤分割出飞行器目标.实验结果表明,该算法改进了以往机场区域提取算法保留候机楼等附属部分以及提取结果中存在机场区域以外区域的缺点,较好地实现了机场停泊飞行器目标的分割,为下一步准确识别飞行器类型奠定了基础.%Considering that the aircraft targets have less scale on the whole image with a complicated background,an algorithm is proposed to segment aircraft targets based on the airport area extracting.Firstly,by using the features of the detecting lines of the Hough transform,the runway and the apron are located.Then,the area out of the airport are wiped off by using some image processing technologies,such as mathematical morphology.After extracting the airport area,a proper threshold value is selected to segment the image.Finally,the aircraft targets are segmented after some steps,such as morphological de-noising and small area removing.The experimental result shows that the algorithm can overcome the disadvantages of the previous algorithms of the airport extraction for retaining the subsidiary parts,such as terminal buildings,thus the extracting results contain area out of the airport area.

  1. 广西壮族传统服饰配件造型艺术研究%A Research of Modeling Art of the Traditional Dress Accessories in Guangxi Zhuang Minority Autonomous Region

    Institute of Scientific and Technical Information of China (English)



    From the angle of function and sex, the traditional clothing accessories items in Guangxi Zhuang Minority Autonomous Region can be classified into four types: men-only, woman-only, man-and-woman-shared, attachment-expressing. The man-and-woman-shared type includes brocade cloth, scouring, GUI (tube) cloth, shoulder pads, "non" shoes and shroud parts; man-only type includes male Cape Horn, tobacco boxes, wedding shoes, bags and head hunting broadsword; women-only accessories include stockings, Tao's hat, apron, Sachet, pointed shoes, woven ribbon and silver jewelry; attachment-expressing type has hydrangea, tokens of love, love fan and purse. This paper has an artistic analysis of them and surveys the artistry of each type. It is hoped this study can deepen the research of the accessories to shed light on the protection of the accessory-type non-material products in Guangxi Zhang Minority Autonomous Region.%针对广西壮族传统服饰上的配件物品,按照性别与功能,将其划分为男女共用、男装、女装和传情类配件四类.男女共用配件包括壮锦、练子布、桂(管)布、垫肩、"非"形鞋和寿衣配件;男装配件包括道公披肩、牛角烟叶盒、圆头婚鞋、猎袋和腰刀;女装配件包括长筒袜、道婆帽、围裙、香袋、尖头鞋、编织彩带和银饰品;传情配饰包括绣球、定情扇和荷包三种.从艺术学的角度分别针对各自的造型进行分析,总结出广西壮族各类典型配饰的造型艺术特点,旨在丰富壮族服饰艺术的研究成果,为壮族传统服饰艺术非物质文化遗产的研究与保护工作提供参考依据.

  2. Pilot study of the dose in crystalline lens in the interventional radiology practice; Estudio piloto de la dosis en cristalino en la practica de radiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Castro, A.; Martinez, A.; Fernandez, A.; Molina, D. [Centro de Proteccion e Higiene de las Radiaciones, Carretera de la Cantera, Victoria II, Km. 21.5 Guanabacoa, La Habana (Cuba); Sanchez, L.; Diaz, A., E-mail: [Hospital Clinico Quirurgico Hermanos Ameijeiras, San Lazaro 701, Centro Habana, La Habana (Cuba)


    The interventional radiology involves considerable exposure levels for the occupationally exposed personnel (OEP). The doses can encompass a wide range of values in dependence of the function that develops the personnel and the complexity of each procedure. In organs like the crystalline lens and skin values can be reached that imply the appearance of deterministic effects if is not fulfilled the appropriate measures of radiological protection. This has been demonstrated through multiple studies, among those that the retrospective study of damages in the crystalline lens and dose has been one of those most commented, known as RELID. The objective of that study was to examine the opacity prevalence in the crystalline lens in workers linked to the interventional cardiology and to correlate it with the occupational exposition. The obtained results contributed to that the ICRP recommend a new limit value of equivalent dose for crystalline lens of 20 mSv in one year. With the objective of analyzing the operational implications, in the radiological surveillance programs that they could originate with the new recommendations was developed a pilot study to evaluate the dose in crystalline lens in the OEP linked to the interventional radiology in a Cuban hospital. For this, an anthropomorphic mannequin RANDO-ALDERSON was used on which thermoluminescent dosimeters were placed below and above of the leaded apron and in different positions at level of the crystalline lens: above, below and to the sides of the leaded lenses that the personnel uses routinely. The mannequin was located on the same positions that occupy the main specialist that execute the procedure, as well as of the nurse to assist him. The measurements were made simulating the more representative procedures about complexity, duration time and exposure rate. The used dosimeters were RADOS model for whole body composed of two thermoluminescent detectors Gr-200 (LiF: Mg, Cu, P) to evaluate personal equivalent dose

  3. Radiation practices 1997

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.


    At the end of 1997, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,065 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,839 radiation sources and 302 radionuclide laboratories. The import of radioactive substances amounted to 1.09 x 10{sup +16} Bq and export to 2.4 x 10{sup +13} Bq. Short-lived radionuclides produced in Finland amounted to 5.2 x 10{sup +13} Bq. There were 11,773 workers monitored for radiation exposure at 1,316 work sites. Of these employees, 24% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 6.6 Sv in 1997, with nuclear power plant workers accounting for 62% of this total. The annual dosemeter reading of thirteen medical doctors (radiologists, interventional radiologists and cardiologists) and six nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of the dosemeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 253 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations in which unusually high exposure to radiation was an unavoidable part of the task. Reports were made of four incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Two of these cases occurred in the medical use of radiation, one in the use of radiation sources in industry, and one in the use of solarium appliances. (orig.)

  4. Systematic error compensation for airborne gravimetry%航空重力测量的系统误差补偿

    Institute of Scientific and Technical Information of China (English)

    孙中苗; 翟振和; 肖云; 李迎春


    基于航空重力测量的基本数学模型,详细分析了航空重力测量的系统误差来源.大致可将系统误差分为三类,即停机坪重力基准值、比力初值的观测误差,格值、交叉耦合系数、摆杆尺度因子的标定误差和水平加速度改正的模型化误差等.然后,对每类系统误差的量级及其补偿方法进行了研究,指出水平加速度改正是引起系统误差的主要因素之一.大同、哈尔滨和渤海湾航空重力测量的实测数据分析均表明,在各项系统误差尤其是水平加速度改正得到有效补偿后,航空重力与地面(或船测)参考值的系统误差将小于1×10-5m· s-2.%Sources of systematic errors in airborne gravity measurements are analyzed in detail using the basic mathematical model. They can be classed into three types. One is the observation error in the apron gravity and the base reading of the airborne gravimeter, the second is the calibration error of cross-coupling correction, beam scale factor and the scale value, and the third is the modeling error for the horizontal acceleration correction. The magnitudes of the various systematic errors are discussed and the related compensation methods are proposed. It is indicated that the modeling error of the horizontal acceleration correction is one of the largest errors. Analysis of real data demonstrates that after compensating the various systematic errors especially the modeling error of the horizontal acceleration correction, the systematic bias between airborne gravity and the ground (or sea) reference value in the Datong and Harbin areas and Bohai Bay are all less than 1×10-5m· s-2.

  5. Termite Damage to Buildings: Nature of Attacks and Preventive Construction Methods

    Directory of Open Access Journals (Sweden)

    Abdel E. Ghaly


    buildings multiple approaches must be used. Before construction begins all nests and palatable wood must be cleared from the site. Once clearing is completed and before construction begins, wood should be selected based on its natural repellency. If no naturally repellent timber is available wood should be impregnated with a chemical preservative. A chemical barrier must be created by treating all exposed wood in the structure with termiticides and all wood should be placed above a concrete footing. Once materials have been selected additional constructional preventative measures consisting of internal preventive measures within the plinth and external preventive measure in form of concrete grooves and interlocking apron floors around the periphery building should be put in place. Educational and promotional activities will further lead to prevention of termite attack to buildings.


    Directory of Open Access Journals (Sweden)

    Rolando Castro Marcelo


    Full Text Available The game as a teaching learning method of athletics in ages ranging from nine to eleven years in Las Tunas province brings about the movement development in school children who can show themselves in a conscious and spontaneous manner. It contributes to their interest and necessities satisfaction through the closed sport in a developing environment which allows to dead with the fundamental dimensions and links with the purpose of reaching the right levels in the formation, education and development of personality in life, here, it is where the talented ones emerge and became high performance athletes. Methodological, epistemological, axiological and critical element in the game declivity; sustained apron theoretical bases are integrated with the intention of permitting the holistic, historic, multifunctional, humanistic and the developing conceptual character. On this point, the unity of theoretical elements and the sport practice is revealed in correspondence with the individual characteristics and peculiarities of catch schoolchild. RESUMEN: El juego como método de enseñanza-aprendizaje del atletismo en las edades de nueve a once años en la provincia de Las Tunas, propicia el desarrollo de los movimientos del escolar, que se pueden manifestar en forma espontánea y consciente, lo que contribuye a la satisfacción por esa vía de sus necesidades e intereses a través del deporte elegido, en un ambiente desarrollador que permite abordar las dimensiones y eslabones fundamentales con el propósito de lograr los niveles deseados de educación, formación y desarrollo de la personalidad, que ha aporte las vías indispensables en su preparación para la vida, de donde emergen los que poseen talento para convertirse en atletas de alto rendimiento. En la actividad del juego se integraron los elementos metodológicos, axiológicos, epistemológicos y críticos, los cuales se sustentan sobre bases teóricas que permiten el carácter holístico, hist

  7. River diversions, avulsions and captures in the Tortuguero coastal plain (United States)

    Galve, Jorge Pedro; Alvarado, Guillermo; Pérez Peña, José Vicente; Azañón, José Miguel; Mora, Mauricio; Booth-Rea, Guillermo


    The Tortuguero area is a coastal plain that forms part of the North Limón sedimentary basin, the back-arc region of the Caribbean side of Costa Rica. This coastal plain is characterised by an abnormal drainage pattern with river captures, diversions and shifts in channel directions. We are analyzing this anomalous drainage network adopting a classical geomorphological approach combined with geomorphometric techniques. The SRTM DEM at 1 arc-second of resolution (~30 m) from NASA, topographic maps 1:50,000, satellital images and the digital cartography of the drainage network have been used for inventorying the channel pattern anomalies. River segments were categorized according to sinuosity, orientation, slope changes and incision using GIS tools. Initially, anomalies in the analyzed river courses suggested that buried thrust fronts could disrupt their natural pattern. However, we have not identified any evidence to link the activity of buried structures with the disruption of natural drainage. Blind thrusts detected through seismic subsurface exploration in the SE sector of the Tortuguero plain do not seem to produce changes in the sinuosity, orientation, slope and incision of rivers as those observed in the deeply studied tectonically active area of the Po Plain (Italy). The identified river pattern anomalies have been explained due to other alternative causes: (1) the migration of the mouths of Reventazón, Pacuare and Matina rivers is produced by sand sedimentation in the coast because of a successive ridge beach formation. This migration to the SE has the same direction than the main ocean currents those deposited the sand. (2) The anomalous course of Parismina river is most probably conditioned by the fracturation of the dissected volcanic apron of Turrialba volcano. (3) Channel migration and capture of Barbilla river by Matina river can be triggered by the tectonic tilting of the coastal plain towards the SE. The subsidence of the SE sector of the plain was

  8. A facies distribution model controlled by a tectonically inherited sea bottom topography in the carbonate rimmed shelf of the Upper Tithonian-Valanginian Southern Tethyan continental margin (NW Sicily, Italy) (United States)

    Basilone, Luca; Sulli, Attilio


    The Upper Tithonian-Valanginian shallow-water carbonates outcropping in the Palermo Mts (NW Sicily) consist of several facies associations reflecting different depositional environments of a carbonate rimmed shelf, pertaining to the Southern Tethyan continental margin. The reconstructed depositional model, based on the sedimentological features, cyclic facies arrangement and biota distribution, shows that a wide protected lagoon, dominated by algae, molluscs and scattered patch reefs, was bordered landward by a tidal flat, where stromatolitic algal mats were cyclically subaerial exposed, and seaward by a marine sand belt and reef complex. Oolitic packstone-grainstone lithofacies, cyclically subjected to subaerial exposure, suggests the occurrence of a barrier island, located nearly to the lagoonal carbonate shoreline, allowing the development of narrow embayments with restricted circulation. In the outer platform, the oolitic lithofacies of the marine sand belt pass landward into the protected lagoon, where washover oolite sands occur, and seaward into a high-energy zone (back-reef apron) gradually merging in the reef complex. In the latter, coral framestone occupied the inner sector (reef flat), while the facies association dominated by boundstone with Ellipsactinia sp. developed in the outer sectors (reef wall), adjacent to the fore-reef and upper slope environments. Stratigraphic evidence, associated with the recognized facies associations, helped to reconstruct the geo-tectonic setting of the carbonate platform, where the distribution of the depositional facies along the shelf and their extension were influenced by the tectonically-inherited sea bottom topography. In a regime of extensional tectonics, localized and thin succession of high-energy prograding oolite sand belt depositional facies occupied structural highs (footwall uplift), while the largely diffused and thick low energy aggrading peritidal-to-lagoonal depositional facies developed in subsiding

  9. Soft sediment deformation in the shallow submarine slope off Nice (France) as a result of a variably charged Pliocene aquifer and mass wasting processes (United States)

    Kopf, Achim J.; Stegmann, Sylvia; Garziglia, Sebastien; Henry, Pierre; Dennielou, Bernard; Haas, Simon; Weber, Kai-Christian


    CPTu, we suggest that a significant part of the Quaternary delta and slope apron deposits are prone to being mobilised without a large external trigger, so that all in all a high risk for a landslide event of considerable size off Nice international airport is identified.

  10. Ionizing radiation exposure in interventional cardiology: current radiation protection practice of invasive cardiology operators in Lithuania. (United States)

    Valuckiene, Zivile; Jurenas, Martynas; Cibulskaite, Inga


    Ionizing radiation management is among the most important safety issues in interventional cardiology. Multiple radiation protection measures allow the minimization of x-ray exposure during interventional procedures. Our purpose was to assess the utilization and effectiveness of radiation protection and optimization techniques among interventional cardiologists in Lithuania. Interventional cardiologists of five cardiac centres were interviewed by anonymized questionnaire, addressing personal use of protective garments, shielding, table/detector positioning, frame rate (FR), resolution, field of view adjustment and collimation. Effective patient doses were compared between operators who work with and without x-ray optimization. Thirty one (68.9%) out of 45 Lithuanian interventional cardiologists participated in the survey. Protective aprons were universally used, but not the thyroid collars; 35.5% (n  =  11) operators use protective eyewear and 12.9% (n  =  4) wear radio-protective caps; 83.9% (n  =  26) use overhanging shields, 58.1% (n  =  18)-portable barriers; 12.9% (n  =  4)-abdominal patient's shielding; 35.5% (n  =  11) work at a high table position; 87.1% (n  =  27) keep an image intensifier/receiver close to the patient; 58.1% (n  =  18) reduce the fluoroscopy FR; 6.5% (n  =  2) reduce the fluoro image detail resolution; 83.9% (n  =  26) use a 'store fluoro' option; 41.9% (N  =  13) reduce magnification for catheter transit; 51.6% (n  =  16) limit image magnification; and 35.5% (n  =  11) use image collimation. Median effective patient doses were significantly lower with x-ray optimization techniques in both diagnostic and therapeutic interventions. Many of the ionizing radiation exposure reduction tools and techniques are underused by a considerable proportion of interventional cardiology operators. The application of basic radiation protection tools and

  11. A review of the geology of the Argentinian Fuegian Andes (United States)

    Olivero, Eduardo B.; Martinioni, Daniel R.


    Seven stratigraphic units reflect the tectonic evolution of the Argentinian Fuegian Andes: Basement (Paleozoic-Jurassic); Lemaire Formation (Upper Jurassic); Yahgan-Beauvoir formations (Lower Cretaceous); Cerro Matrero Formation (Upper Cretaceous); Rı´o Claro Formation (Paleocene); La Despedida Group (Eocene); and Cabo Peña Formation (uppermost Eocene-Lower Oligocene). Basement rocks (garnet, quartz-sericite, and chlorite schists; and amphibolites) are unconformably covered by the Lemaire Formation (rhyolites; basalts; slates; and acidic volcaniclastic breccias, tuffs, conglomerates, and turbidites), formed during extensional tectonism. The post-rift Yahgan Formation (deep-marine black mudstones, andesitic volcaniclastic turbidites and tuffs) interfingers northward with the Beauvoir Formation (slope and platform black mudstones), and covers the Lemaire Formation unconformably. The Yahgan Formation represents an andesitic, volcaniclastic apron, coeval with a Pacific volcanic-arc, filling a marginal basin floored with oceanic crust. The Late Cretaceous compressional orogeny resulted in tectonic inversion, closure of the marginal basin, peak metamorphism and folding, and initial uplifting of the Fuegian Andes. By the latest Cretaceous-earliest Paleogene, the Andes were exposed to subaerial erosion, and the lowest Danian Rı´o Claro Formation bears clear evidence of an Andean clastic provenance. The Rı´o Claro Formation represents the first molasse deposits of the foreland stage of evolution of the Fuegian Andes. Earliest Paleogene north-verging thrust propagation deformed the Rı´o Claro Formation and older units, producing northward depocenter migration. La Despedida Group rests unconformably on the Rı´o Claro Formation and is involved in the thrust and fold belt. Important Eocene compression resulted in thrusting of central Andean basement schists and the Lemaire Formation over Lower Cretaceous and continental Paleogene rocks, respectively. In the

  12. Microbial lifestyles that enable survival in lithifying habitats (United States)

    Hirst, M.; Dossing, L. N.; Tamez, P.; Ziegler, S.; Hanselmann, K.; Sessions, A. L.; Spear, J. R.; Johnson, H.; Berelson, W.; Corsetti, F. A.; Dawson, S.; de la Torre, J. R.; Usc Wrigley Institute, I.


    The precipitation of carbonates in the travertine forming Narrow Gauge hot spring in Yellowstone National Park occurs at a rapid rate, whereby microorganisms that colonize the ponds and apron facies are required to overcome lithification. CO2-fixation by autotrophic microorganisms in this cation-rich environment further promotes carbonate encapsulation. Microorganisms that alter their micro-habitat through dissimilative metabolic processes such as H2S and NH4+oxidation, can decrease acid neutralizing capacity (ANCcarb = [HCO3-] + 2[CO32-] + [OH-] - [H+] ) and locally delay CaCO3 mineralization. Genomic and geochemical approaches were combined to study the metabolic processes and microbial populations in a sulfidic hot spring emerging from a carbonate fissure ridge. Samples from locations close to the discharge vent and along its outflow channel were preserved for DNA sequencing, ATP measurements, microscopy, ion chromatographic and ICP-MS analyses of the major solutes and for ANC titration. Temperature, conductivity and pH were measured at the sampling sites. A pyrotagged 16S rRNA gene sequencing approach at both sites was used along with a publicly accessible metagenome of a similar site at the same location. The 16S rRNA gene sequence analyses reveal a great diversity of phylotypes related to species with known physiological potentials. The diversity at the vent is greater and more even than at the cooler site 6m downstream. A number of genes for C-1 fixing enzymes point to the presence of the reductive citric acid cycle, as well as to parts of the reductive acetyl-CoA pathway, the 3-hydroxypropionate cycle and the serine cycle as dominant forms of carbon metabolism. A complete set of genes for all enzymes of the reductive citric acid cycle were found, which indicates a dominance of this pathway for carbon fixation. Surprisingly, genes for RubisCo appear to be absent. Almost all genes found for enzymes that catalyze the conversion of sulfur compounds are involved

  13. Sea Level History in 3D: Early results of an ultra-high resolution MCS survey across IODP Expedition 313 drillsites (United States)

    Mountain, G. S.; Kucuk, H. M.; Nedimovic, M. R.; Austin, J. A., Jr.; Fulthorpe, C.; Newton, A.; Baldwin, K.; Johnson, C.; Stanley, J. N.; Bhatnagar, T.


    Although globally averaged sea level is rising at roughly 3 mm/yr (and is accelerating), rates of local sea-level change measured at coastlines may differ from this number by a factor of two or more; at some locations, sea level may even be falling. This is due to local processes that can match or even reverse the global trend, making it clear that reliable predictions of future impacts of sea-level rise require a firm understanding of processes at the local level. The history of local sea-level change and shoreline response is contained in the geologic record of shallow-water sediments. We report on a continuing study of sea-level history in sediments at the New Jersey continental margin, where compaction and glacial isostatic adjustment are currently adding 2 mm/yr to the globally averaged rise. We collected 570 sq km of ultra-high resolution 3D MCS data aboard the R/V Langseth in June-July 2015; innovative recording and preliminary results are described by Nedimovic et al. in this same session. The goal was to provide regional context to coring and logging at IODP Exp 313 sites 27-29 that were drilled 750 m into the New Jersey shelf in 2009. These sites recovered a nearly continuous record of post-Eocene sediments from non-marine soils, estuaries, shoreface, delta front, pro-delta and open marine settings. Existing seismic data are good but are 2D high-resolution profiles at line spacings too wide to enable mapping of key nearshore features. The Langseth 3D survey used shallow towing of a tuned air gun array to preserve high frequencies, and twenty-four 50-m PCables each 12.5 apart provided 6.25 x 3.125 m common-midpoint bins along seventy-seven 50-km sail lines. With this especially dense spatial resolution of a pre-stack time migrated volume we expect to map rivers, incised valleys, barrier islands, inlets and bays, pro-delta clinoforms, tidal deltas, sequence boundaries, debris flow aprons, and more. Seismic attributes linked to sedimentary facies and

  14. Morphology, volcanism, and mass wasting in Crater Lake, Oregon (United States)

    Bacon, C.R.; Gardner, J.V.; Mayer, L.A.; Buktenica, M.W.; Dartnell, P.; Ramsey, D.W.; Robinson, J.E.


    Crater Lake was surveyed nearly to its shoreline by high-resolution multibeam echo sounding in order to define its geologic history and provide an accurate base map for research and monitoring surveys. The bathymetry and acoustic backscatter reveal the character of landforms and lead to a chronology for the concurrent filling of the lake and volcanism within the ca. 7700 calibrated yr B.P. caldera. The andesitic Wizard Island and central-plattform volcanoes are composed of sequences of lava deltas that record former lake levels and demonstrate simultaneous activity at the two vents. Wizard Island eruptions ceased when the lake was ~80 m lower than at present. Lava streams from prominent channels on the surface of the central platform descended to feed extensive subaqueous flow fields on the caldera floor. The Wizard Island and central-platform volcanoes, andesitic Merriam Cone, and a newly discovered probable lava flow on the eastern floor of the lake apparently date from within a few hundred years of caldera collapse, whereas a small rhydacite dome was emplaced on the flank of Wizard Island at ca. 4800 cal. yr B.P. Bedrock outcrops on the submerged caldera walls are shown in detail and, in some cases, can be correlated with exposed geologic units of Mount Mazama. Fragmental debris making up the walls elsewhere consists of narrow talus cones forming a dendritic pattern that leads to fewer, wider ridges downslope. Hummocky topography and scattered blocks up to ~280 m long below many of the embayments in the caldera wall mark debris-avalanche deposits that probably formed in single events and commonly are affected by secondary failures. The flat-floored, deep basins contain relatively fine-grained sediment transported from the debris aprons by sheet-flow turbidity currents. Crater Lake apparently filled rapidly (ca. 400-750 yr) until reaching a permeable layer above glaciated lava identified by the new survey in the northeast caldera wall at ~1845 m elevation

  15. Geology of the Ugashik-Mount Peulik Volcanic Center, Alaska (United States)

    Miller, Thomas P.


    The Ugashik-Mount Peulik volcanic center, 550 km southwest of Anchorage on the Alaska Peninsula, consists of the late Quaternary 5-km-wide Ugashik caldera and the stratovolcano Mount Peulik built on the north flank of Ugashik. The center has been the site of explosive volcanism including a caldera-forming eruption and post-caldera dome-destructive activity. Mount Peulik has been formed entirely in Holocene time and erupted in 1814 and 1845. A large lava dome occupies the summit crater, which is breached to the west. A smaller dome is perched high on the southeast flank of the cone. Pyroclastic-flow deposits form aprons below both domes. One or more sector-collapse events occurred early in the formation of Mount Peulik volcano resulting in a large area of debris-avalanche deposits on the volcano's northwest flank. The Ugashik-Mount Peulik center is a calcalkaline suite of basalt, andesite, dacite, and rhyolite, ranging in SiO2 content from 51 to 72 percent. The Ugashik-Mount Peulik magmas appear to be co-genetic in a broad sense and their compositional variation has probably resulted from a combination of fractional crystallization and magma-mixing. The most likely scenario for a future eruption is that one or more of the summit domes on Mount Peulik are destroyed as new magma rises to the surface. Debris avalanches and pyroclastic flows may then move down the west and, less likely, east flanks of the volcano for distances of 10 km or more. A new lava dome or series of domes would be expected to form either during or within some few years after the explosive disruption of the previous dome. This cycle of dome disruption, pyroclastic flow generation, and new dome formation could be repeated several times in a single eruption. The volcano poses little direct threat to human population as the area is sparsely populated. The most serious hazard is the effect of airborne volcanic ash on aircraft since Mount Peulik sits astride heavily traveled air routes connecting the U

  16. A Description of Sub-Equatorial Volcanic Structures Consistent with Sub-Ice Magmatism East of Nepenthes Mensae, Mars. (United States)

    Caprarelli, G.; de Pablo Hernandez, M. A.


    The Martian region located immediately north of the dichotomy scarp, between latitudes 120°E and 135°E, is covered by fretted terrains, characterised by the presence of knobs and mesas formed by eroded and reworked material of highlands provenance, and the smoother terrains between them [1]. Topographic depressions of oblong shape, generally parallel to the scarp, of rough and chaotic appearance, are also observed. The high resolution (~ 6 m/pixel, [2]) Context Camera (CTX) on board Mars Reconnaissance Orbiter (MRO) makes it possible to examine the morphologies of these topographic depressions in great detail, unveiling their complex geological histories. Here we expand on our earlier work in the adjacent Nepenthes Mensae region [3] and present the results of our observations of morphologies of likely igneous origin. We identified a variety of shapes consistent with magmatic structures and constructs: dikes, collapsed lava tubes, and lava flows are observable in the smoother terrains. Most of the elevated structures in the areas are strongly eroded knobs and mesas covered by dust and debris. In some cases however, the morphological characteristics of 2-10 km-size structures are clear and sharp, which allowed us to identify features consistent with sub-ice volcanic constructs, such as tuyas and tindars [4]. Geological reconstructions involving magma-ice interaction are supported by the presence of lobate aprons around knobs and mesas, and of scalloped ejecta surrounding complex impact craters, suggesting the existence of ice both underground and on the surface of these low elevation areas at the time of formation of these constructs. [1] Tanaka et al. (2005) Geologic Map of the Northern Plains of Mars. USGS SIM 2888. [2] Malin et al. (2007) Context Camera investigation on board the Mars Reconnaissance Orbiter. JGR 112, E05S04, 10.1029/2006JE002808. [3] dePablo and Caprarelli (2010) Possible subglacial volcanoes in Nepenthes Mensae, eastern hemisphere, Mars. LPSC

  17. Glacial Processes on Earth and Mars: New Perspectives from Remote Sensing and Laboratory Analyses (United States)

    Rutledge, Alicia Marie

    Chemical and physical interactions of flowing ice and rock have inexorably shaped planetary surfaces. Weathering in glacial environments is a significant link in biogeochemical cycles --- carbon and strontium --- on Earth, and may have once played an important role in altering Mars' surface. Despite growing recognition of the importance of low-temperature chemical weathering, these processes are still not well understood. Debris-coated glaciers are also present on Mars, emphasizing the need to study ice-related processes in the evolution of planetary surfaces. During Earth's history, subglacial environments are thought to have sheltered communities of microorganisms from extreme climate variations. On Amazonian Mars, glaciers such as lobate debris aprons (LDA) could have hosted chemolithotrophic communities, making Mars' present glaciers candidates for life preservation. This study characterizes glacial processes on both Earth and Mars. Chemical weathering at Robertson Glacier, a small alpine glacier in the Canadian Rocky Mountains, is examined with a multidisciplinary approach. The relative proportions of differing dissolution reactions at various stages in the glacial system are empirically determined using aqueous geochemistry. Synthesis of laboratory and orbital thermal infrared spectroscopy allows identification of dissolution rinds on hand samples and characterization of carbonate dissolution signals at orbital scales, while chemical and morphological evidence for thin, discontinuous weathering rinds at microscales are evident from electron microscopy. Subglacial dissolution rates are found to outpace those of the proglacial till plain; biologically-mediated pyrite oxidation drives the bulk of this acidic weathering. Second, the area-elevation relationship, or hypsometry, of LDA in the midlatitudes of Mars is characterized. These glaciers are believed to have formed ˜500 Ma during a climate excursion. Hypsometric measurements of these debris-covered glaciers

  18. Results from SCS Profiling of the Sumatra accretionary prism: insights into tsnamigenesis (United States)

    Fisher, D.; Mosher, D.; Austin, J.; Gulick, S.; Moran, K.; Masterlark, T.


    The SEATOS high resolution single-channel seismic reflection survey of the Sumatran accretionary prism depicts a landward-vergent thrust front, with active folding characterizing part of the December 2004 Mw9.2 earthquake rupture zone. Structure and bathymetry co-vary at distinct wavelengths along a 220-km-long profile crossing the prism and the Aceh (forearc) Basin. At the largest wavelength (tens of kms), the prism surface is defined by a steep (8-12 degrees), 55-km-wide outer slope, a 110-km-wide upper slope forming a broad depression between two forearc highs, and a 25 km-wide, steep inner slope between the landward high and the forearc basin. Anticlinal ridges spaced ~13 km apart display landward- and seaward-vergent folds along the inner and outer slopes, respectively; symmetric folding occurs across the upper slope. We suggest that the long-wavelength variations are consistent with the existence of a strong inner wedge beneath the upper slope. The ~13 km anticline spacing implies deformation of a slope apron deforming independently of this stronger wedge interior. Seismic profiles crossing the toe of the prism image a series of landward vergent, fault-related folds, suggesting that the shallow fill of the Sunda Trench is delaminated from the predominantly seaward-vergent plate boundary system and is uptilted along a triangle zone. Profiles crossing the seaward flank of the Aceh Basin reveal a near- vertical, undulatory deformation front that appears to mark the location of the West Andaman-Mentawai right- lateral strike-slip fault zone. Our model for prism architecture based on these geophysical results involves advance of the strong inner wedge during great earthquakes like the 2004 event, which then peels up shallower and less competent trench fill, deforming the toe and the upper slope of the forearc, producing massive uplift that is likely tsunamigenic. Seismic rupture was limited to the megathrust westward of the West Andaman fault and ROV observations

  19. The stratigraphy, depositional processes, and environment of the late Pleistocene Polallie-period deposits at Mount Hood Volcano, Oregon, USA (United States)

    Thouret, Jean-Claude


    The Polallie eruptive period of Mt. Hood, Oregon, is the last major episode of eruption and dome growth, before the late Holocene activity which was centered at Crater Rock. A volume of 4-8 km 3 of Polallie deposits forms an apron of ca. 60 km 2 on the east, northeast and southeast flanks. The Polallie deposits can be divided, stratigraphically, into four groups: Group I rockslide avalanche and pyroclastic-flow deposits; Group II debris-flow and pyroclastic-flow deposits that suggest some explosive activity and remobilization of pyroclastic debris in a glacial environment; Group III block-and-ash flow deposits that attest to summit dome growth; Group IV alternating debris-flow deposits, glacial sediments, and reworked pyroclastic-flow deposits that indicate a decrease in dome activity and an increase in erosion and transport. Group III clearly indicates frequent episodes of dome growth and collapse, whereas Groups II and IV imply increasing erosion and, conversely, decreasing volcanic activity. The Polallie period occurred in the late Pleistocene during and just after the last Alpine glaciation, which is named Evans Creek in the Cascade Range. According to four K-Ar age dates on lava flows interbedded with Polallie deposits and to published minimum 14C ages on tephra and soils overlying these deposits, the Polallie period had lasted 15,000-22,000 years between 28-34 ka and 12-13 ka. From stratigraphic subdivisions, sedimentary lithofacies and features and from the grain-size and geochemical data, we infer that the Polallie depositional record is a result of the interplay of several processes acting during a long-lasting period of dome growth and destruction. The growth of several domes near the present summit was intermittent, because each group of sediments encompasses primary (pyroclastic) and secondary (volcaniclastic and epiclastic) deposition. Direct deposition of primary material has occurred within intervals of erosion that have probably included meltwater


    Directory of Open Access Journals (Sweden)

    Tomasz Jankowski


    operating room were deter-mined on the basis of VelociCalc 8360 and Testo 435 anemometers with a 3-function probe and 3 vane probes with the diameter of 16 mm, 60 mm and 100 mm. Throughout the study, microclimate conditions in the operating rooms were controlled by the EHA MM101 microclimate meter. Test results showed that the microclimate parameters met the requirements of the aforementioned documents. However, individual thermal sensations reported by the medical staff pointed to the lack of thermal comfort and, in extreme cases, e.g. when using lead aprons during operations, perception of the thermal environment as ‘very hot’. The efficiency and type of air distribution in operating rooms has a decisive effect on the results.

  1. Veiki-moraine-like landforms in Nereidum Montes on Mars: Insights from analogues in northern Sweden. (United States)

    Johnsson, Andreas; Reiss, Dennis; Hauber, Ernst; Johnson, Mark D.; Olvmo, Mats; Hiesinger, Harald


    Mars is a cold hyper-arid planet where liquid water is extremely rare [1]. The observable water budget is instead found in a number of frozen reservoirs such as the polar caps, near surface ground ice and as glacier ice. Previously, numerous studies reported on glacier landforms such as viscous flow features and lobate debris aprons where water-ice is believed to be present under insulating debris cover [2]. This notion was confirmed by SHARAD measurements [3]. However, very little is known about glacial landforms in which water is an important factor. Most studies have focused on moraine-like ridges that are associated to gully systems [4], glacial landforms at the equatorial volcanic province [5] and possible drop-moraines from CO2 glaciers [6]. Here we report on an unusual lobate assemblage of irregular ring-shaped landforms within a mountain complex in Nereidum Montes, Mars. These landforms are well-preserved and may suggest recent ablation of a debris-covered glacier. These martian ring-shaped landforms show a striking morphological resemblance to the Veiki moraine in northern Sweden. Veiki moraines are believed to have formed at the lobate margins of a stagnant ice-sheet during the first Weichselian glaciation [7]. As it sharply ends to the east it may represent the maximum extent of this former ice sheet. The Veiki moraine is characterized by ridged plateaus that are more or less circular and surrounded by a rim ridge. The newly acquired national LiDAR data over Sweden enable us studying these landforms in unprecedented detail. They also enable us exploring geomorphological similarities between Earth and Mars in large spatial contexts. This study aims to increase our understanding of glacial landforms on Mars by comparison to terrestrial analogues. Questions addressed are: (1) How morphological similar are the Martian landforms to the Veiki moraine of Sweden? (2) How does the ring-shaped landforms relate to other possible glacial landforms within the

  2. Radiation practices 1996

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.


    At the end of 1996, there were 1,762 valid safety licences in Finland for the use of radiation. In addition, there were 2,052 responsible parties for dental x-ray diagnostics. The registry of the Finnish Centre for Radiation and Nuclear Safety listed 13,360 radiation sources and 313 radionuclide laboratories. The import of radioactive substances amounted to 1.14 x 10{sup +16} Bq and export to 7.78 x 10{sup +13} Bq. A total of 4.02 x 10{sup +13} Bq of short-lived radionuclides were produced in Finland. There were 11,842 workers monitored for radiation exposure at 1,352 work sites. Of these employees, 27% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of individual dosimeter readings) was 7.96 manSv in 1996, with nuclear power plant workers accounting for 69% of this total. The annual dosimeter reading of ten medical doctors (radiologists, interventional radiologists and cardiologists) and eight nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of dosimeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 242 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations where unusually high exposure to radiation was an unavoidable part of the task. Report was made of 12 incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Five of these cases occurred in radiotherapy, three in use of a radiation source in industry, three in transport of radiation sources and one in use of solarium appliances. Radiation-contaminated material was found in 17 shipments of scrap. (orig.)

  3. Intraoral radiology in general dental practices. A comparison of digital and film-based X-ray systems with regard to radiation protection and dose reduction

    Energy Technology Data Exchange (ETDEWEB)

    Anissi, H.D. [Ulm Univ. (Germany). Dentistry; Geibel, M.A. [Ulm Univ. (Germany). Dept. of Dentomaxillofacial Surgery


    Purpose: The purpose of this study was to gain insight into the distribution and application of digital intraoral radiographic techniques within general dental practices and to compare these with film-based systems in terms of patient dose reduction. Materials and Methods: 1100 questionnaires were handed out to general dental practitioners. Data was analyzed with respect to the type of system by using descriptive statistics and nonparametric tests, i.e. Kruskal-Wallis, Mann-Whitney and chi-square test (SPSS 20). Results: 64% of the questioned dentists still use film-based radiology, 23% utilize storage phosphor plate (SPP) systems and 13% use a charge-coupled device (CCD). A strong correlation between the number of dentists working in a practice and the use of digital dental imaging was observed. Almost 3/4 of the film users work with E- or F-speed film. 45% of them refuse to change to a digital system. The use of lead aprons was popular, while only a minority preferred thyroid shields and rectangular collimators. A fourfold reduction of exposure time from D-speed film to CCD systems was observed. Due to detector size and positioning errors, users of CCD systems take significantly more single-tooth radiographs in total. Considering the number of radiographs per patient, there is only a slight tendency towards more X-rays with CCD systems. Up to image generation, digital systems seem to be as or even more difficult to handle than film-based systems, while their handling was favored after radiographic exposure. Conclusion: Despite a slight increase of radiographs taken with CCD systems, there is a significant dosage reduction. Corresponding to the decrease in exposure time, the patient dose for SPP systems is reduced to one half compared to film. The main issues in CCD technology are positioning errors and the size of the X-ray detectors which are difficult to eliminate. The usage of radiation protection measures still needs to be improved. (orig.)

  4. GPR in Ramboll (United States)

    Ringgaard, Jørgen; Wisén, Roger


    has contributed to aninternational collaboration between several countries about preparation of guidelines for application of GPR on roads, the Mara Nord Project. Our 3D system is used for various types of surveys. In airports mapping has been performed both on runways, taxiways and aprons with the aim of mapping layer thicknesses and delamination for planning of maintenance work. Acquisition has also been done on roads for control of asphalt works and mapping of the road bed. On bridges mapping of rebars and structure has been performed. The 3D system is also used for determination of space behind frost insulation walls in tunnels in Norway. This work is based on a pilot project made by SINTEF in Norway. This abstract is a contribution to COST Action TU1208.

  5. Channel and tube flow features associated with the Twin Craters Lava Flow, Zuni-Bandera Volcanic Field, NM: Insights into similar features on Mars (United States)

    Samuels, R.; deWet, A.; Bleacher, J. E.; von Meerscheidt, H. C.; Hamilton, C.; Garry, W. B.


    The Zuni-Bandera Volcanic Field lies near the center of the Jemez lineament that extends from central Arizona to northeastern New Mexico. The Jemez lineament is a result of rifting in the Earth's crust and is associated with volcanic activity that spans the last 16 Ma. The youngest volcanic activity associated with the lineament includes basaltic lava that was erupted 3 ka ago to form the McCartys Flow. The Twin Craters flow is moderately older (18.0 ka), but it also well-preserved and provides an ideal location to investigate volcanic processes and landforms. In this study, we combined detailed field observations and mapping with remote sensing to better understand variations in morphology along the transport system of the flow . The Twin Craters flow is characterized as an aā and tube-fed pāhoehoe flow with braided or branching tubes and channels; and associated aā and pāhoehoe break-outs. It is possible that the variations in morphology along the same transport structure might be related to pre-flow slope, which might have also been variable along flow. Shatter ring features are thought to be related to changes in eruption rate, and therefore, local flux through the system. However, over-pressurization of the tube might also be related to changes in local discharge rate associated with the ponding and release of lava within the transport system that may be due to interactions between the lava and obstacles along the flow's path (see Mallonee et al., this meeting). Many of these features are similar to features present in the Tharsis Montes region of Mars and particularly on the southern apron of Ascraeus Mons. The detailed description of the morphology of the Twin Craters Lava Flow and the understanding of the emplacement mechanisms will be crucial in identifying the processes that formed the Ascraeus flows and channels. This will aid in determining if the lava surface textures are directly related to eruption conditions or if they have been significantly

  6. Seabed Filter Feasibility Study of Om Almisk Island

    KAUST Repository

    Sesler, Kathryn


    Freshwater access has always been and is continuing to be a severe problem in desert coastal regions, despite the fact that they have an unlimited supply of easily accessible saline water. Water desalination plants are well established and heavily relied upon throughout the Middle East, Saudi Arabia in particular. However, water desalination tends to be a very expensive and energy intensive solution to the problem. The transition from using open water intake systems and all of the pretreatment processes that they require, to using seabed water filters as an intake, would potentially reduce the lifetime costs, energy consumption, and environmental impacts commonly associated with water desalination. This is because the filtration process that the seabed filter generates, serves as sufficient pretreatment for seawater as well as eliminating any risk of entrainment or impingement of marine organisms. The main objective of this research is to conduct a feasibility study on Om Almisk Island, an island off the coast of King Abdullah University of Science and Technology (KAUST), to determine if it would be a suitable location to construct a seabed water filter as a replacement for the current open water intake. The Om Almisk Island site was evaluated through collection of sand samples over a radial grid around Om Almisk Island and sample analysis using grain size distribution, porosity, and hydraulic conductivity. The lack of mud, high hydraulic conductivity, proximity to KAUST, and the shallow waters of the sandy apron surrounding Om Almisk Island make this an ideal location for a seabed water filter to be used as an intake and pretreatment for the KAUST desalination plant. This location also has low tide change and the presence of benthic macrofauna to create bioturbation in the sediments, which could inhibit the growth of a schmutzdecke. If this biological layer forms, it could drastically reduce the hydraulic conductivity of the system. Due to the high hydraulic

  7. Testing Penetration of Epoxy Resin and Diamine Hardeners through Protective Glove and Clothing Materials. (United States)

    Henriks-Eckerman, Maj-Len; Mäkelä, Erja A; Suuronen, Katri


    Efficient, comfortable, yet affordable personal protective equipment (PPE) is needed to decrease the high incidence of allergic contact dermatitis arising from epoxy resin systems (ERSs) in industrial countries. The aim of this study was to find affordable, user-friendly glove and clothing materials that provide adequate skin protection against splashes and during the short contact with ERS that often occurs before full cure. We studied the penetration of epoxy resin and diamine hardeners through 12 glove or clothing materials using a newly developed test method. The tests were carried out with two ERS test mixtures that had a high content of epoxy resin and frequently used diamine hardeners of different molar masses. A drop (50 µl) of test mixture was placed on the outer surface of the glove/clothing material, which had a piece of Fixomull tape or Harmony protection sheet attached to the inner surface as the collection medium. The test times were 10 and 30 min. The collecting material was removed after the test was finished and immersed into acetone. The amounts of diglycidyl ether of bisphenol A (DGEBA), isophorone diamine (IPDA), and m-xylylenediamine (XDA) in the acetone solution were determined by gas chromatography with mass spectrometric detection. The limit for acceptable penetration of XDA, IPDA, and DGEBA through glove materials was set at 2 µg cm(-2). Penetration through the glove materials was 1.4 µg cm(-2) or less. The three tested chemical protective gloves showed no detectable penetration (<0.5 µg cm(-2)). Several affordable glove and clothing materials were found to provide adequate protection during short contact with ERS, in the form of, for example, disposable gloves or clothing materials suitable for aprons and as additional protective layers on the most exposed parts of clothing, such as the front of the legs and thighs and under the forearms. Every ERS combination in use should be tested separately to find the best skin protection material


    Directory of Open Access Journals (Sweden)



    Full Text Available The Transdanubian Central Range (TCR is a flattened range of hills in northern Transdanubia (Hungary, formed mainly by Mesozoic carbonate rocks showing strong facies similarities with the Southern Alps and the Austroalpine domain. The Jurassic system is divided into several formations of predominantly pelagic limestones. Ammonoids are frequent and were collected bed-by-bed in numerous sections, providing an excellent biostratigraphic resolution. The thickness of the Jurassic system is usually small but changes along the strike of the TCR. It reaches a maximum thickness of 500 m in the western part; is very variable (10-400 m in the central segment (Bakony Mts. and rather low (less than 100 m in the east (Gerecse. In the Bakony segment, the thickness variation reflects the strongly dissected topography of the Jurassic sea-floor. Synsedimentary tectonics is dominated by normal faults; tilted blocks and listric faults may be inferred only in the east.Five main steps were identified in the palaeogeographic evolution: 1 Late Hettangian: carbonate oolitic shoals prevail, except for a few sites where non-deposition or neritic sediments occur. 2 Sinemurian and Pliensbachian: tectonic disintegration resulted in an intricate pattern of submarine horsts and intervening basins, with condensed sedimentation or non-deposition on the horsts and thicker, continuous sedimentary sequences in the basins. The submarine topographic highs are surrounded by aprons of redeposited material (scarp breccias, brachiopod coquinas, crinoidal calcarenites, spiculitic cherty limestones, while pure or argillaceous limestones (Rosso Ammonitico prevail in the distal areas. 3 Early Toarcian: the Tethys-wide anoxic event is superimposed on the previous submarine bottom topography; the resulting black shales and sedimentary Mn-ores are concentrated on the western sides of some horsts. 4 Dogger to Early Malm: radiolarites with heterochronous lower and upper boundaries (Aalenian to

  9. Fine-Grained Turbidites: Facies, Attributes and Process Implications (United States)

    Stow, Dorrik; Omoniyi, Bayonle


    Within turbidite systems, fine-grained sediments are still the poor relation and sport several contrasting facies models linked to process of deposition. These are volumetrically the dominant facies in deepwater and, from a resource perspective, they form important marginal and tight reservoirs, and have great potential for unconventional shale gas, source rocks and seals. They are also significant hosts of metals and rare earth elements. Based on a large number of studies of modern, ancient and subsurface systems, including 1000s of metres of section logging, we define the principal genetic elements of fine-grained deepwater facies, present a new synthesis of facies models and their sedimentary attributes. The principal architectural elements include: non-channelised slope-aprons, channel-fill, channel levee and overbank, turbidite lobes, mass-transport deposits, contourite drifts, basin sheets and drapes. These comprise a variable intercalation of fine-grained facies - thin-bedded and very thin-bedded turbidites, contourites, hemipelagites and pelagites - and associated coarse-grained facies. Characteristic attributes used to discriminate between these different elements are: facies and facies associations; sand-shale ratio, sand and shale geometry and dimensions, sand connectivity; sediment texture and small-scale sedimentary structures; sediment fabric and microfabric; and small-scale vertical sequences of bed thickness. To some extent, we can relate facies and attribute characteristics to different depositional environments. We identify four distinct facies models: (a) silt-laminated mud turbidites, (b) siliciclastic mud turbidites, (c) carbonate mud turbidites, (d) disorganized silty-mud turbidites, and (e) hemiturbidites. Within the grainsize-velocity matrix turbidite plot, these all fall within the region of mean size < 0.063mm, maximum grainsize (one percentile) <0.2mm, and depositional velocity 0.1-0.5 m/s. Silt-laminated turbidites and many mud

  10. A Comparison of Disturbance Events in Cascadia Lakes to Marine Seismogenic Turbidites (United States)

    Morey, A. E.; Goldfinger, C.; Briles, C.; Gavin, D. G.; Colombaroli, D.; Kusler, J.


    (days to weeks), whereas the lack of an oxidation profile through a deposit of the same thickness would suggest the introduction of sediment more slowly through time from the watershed. A comparison of the gamma and CT density from this deposit to a marine turbidite deposit (dated at 1480(1310-1620) BP) from Smith Apron core M9907-33TC show remarkable similarities. The great distance and multiple depositional environments over which these events correlate suggests these are earthquake-generated deposits and supports the hypothesis that gravity-driven seismogenic deposits may record a crude primary signal of shaking we call a "paleoseismogram". Simple limit equilibrium calculations of slope stability (pseudostatic) suggest expected PGA for these inland sites is likely sufficient to trigger sediment failures within the lakes from subduction earthquakes with Mw as low as 8.0.

  11. Euripus Mons - Landform Evolution and Climate Constraints in Promethei Terra (United States)

    van Gasselt, Stephan; Kim, Jungrack; Baik, Hyun-Seob


    The Promethei Terra region of Mars exhibits a variety of geomorphic landforms indicative of ice-assisted creep of debris and ice, similar to features and processes found at the Martian dichotomy boundary in Deuteronilus, Protonilus and Nilosyrtis Mensae. Despite only little doubt about the fact that ice played an integral role in the formation of these features, it is still disputed if these features were formed by glacial processes, requiring precipitation of ice and snow and exhibiting glacial deformation and basal sliding, or if these landforms are a product of periglacial denudation and subject to different deformation regimes. As information about past climate conditions on Mars is sparse, the proper assessment of landform types today allows to put constraints on their environmental conditions in the past. Due to limited knowledge about the internal physical and thermal structure of these landforms, it remains impossible to unambiguously determine their origin [1]. A variety of geomorphic and model-based indicators need to be taken into account when putting constraints on their history and when trying to reconstruct their evolution. For selected features on Mars it has been shown by SHARAD radar observations that the ice content might be relatively high [2], and that some of them might be composed of pure ice, protected from sublimation by a thin debris cover. One of such examples, Euripus Mons, is a 80 km remnant feature with an associated circumferential talus deposit that shows indicators for deformation by downslope movement, i.e. debris apron morphology. Recent modelling assuming glacial deformation helped to reconstruct some internal structural properties [3]. Despite these attempts, Euripus Mons shows clear geomorphic signatures of classical periglacial denudation which do not fit into the concept of glacial-only evolution. Denudation rates as well as ages are similar to those reported from other locations on Mars for which hyperarid climate conditions

  12. Rediscovery of the 8th Natural Wonder of the World: The Pink and White Terraces' survival of the 1886 Tarawera Rift eruption (United States)

    de Ronde, C. E.; Fornari, D. J.; Ferrini, V.; Caratori Tontini, F.; Walker, S. L.; Scott, B. J.; Leybourne, M. I.; Pittari, A.; Keam, R. F.; Lupton, J. E.; Mazot, A.; Kukulya, A.; Littlefield, R.; Immenga, D.; Stagpoole, V.; Timm, C.; Berthelsen, T. J.


    On June 10, 1886, Mt. Tarawera in the rhyolitic Okataina Volcanic Centre of the central North Island, New Zealand, erupted in spectacular fashion. Basaltic eruptions at Tarawera produced tall eruption columns, while hydrothermal and phreatomagmatic eruptions at Rotomahana excavated the pre-1886 Lake Rotomahana site, which later filled to form a new lake up to 125 m deep and ~5 x larger than its predecessor. The Pink and White Terraces, which were the world's largest silica aprons and buttresses, had formed as a result of discharging thermal waters and deposition of silica on the margins of the pre-1886 lake, and were believed destroyed during the 1886 eruption. The post-eruption landscape was scarred by eruption craters with the largest marking the foci of the phreatomagmatic eruption, which blanketed the area with 10s of m of mud. A combined ~250 line km survey of Lake Rotomahana was conducted using two REMUS 100 AUVs simultaneously mapping with multibeam and sidescan sonar. Also fitted were a magnetometer, minature plume recorders (LSS, Eh, temperature, depth) and pH sensors. Surface vessels conducted magnetic surveys (110 line km), CO2 flux measurements (420 sites), deployed a CTD and Niksin bottles for water properties and sampling (14 stations), and a camera over sites (12) of known venting and/or where the sidescan showed evidence for the terraces. New bathymetric data clearly shows the en-echelon rift of 1886 in the center of the lake and identifies some pre-1886 shoreline. When combined with sidescan sonar images, several of the basal layers of the Pink Terraces were found very near their original, pre-eruption locations. Underwater photographs reveal buttresses of several tiers. Magnetic data show a pronounced positive anomaly in the southern part of the lake, associated with older lavas, and a distinct negative anomaly associated with the Pink Terraces, marking the boundaries of the pre-1886 geothermal field. Bubble plumes recorded during the magnetic

  13. Radiation exposure evaluation of the professional working interventionist procedures in a hemodynamics service; Avaliacao da exposicao a radiacao dos profissionais que executam procedimentos intervencionistas em um servico de hemodinamica

    Energy Technology Data Exchange (ETDEWEB)

    Da Silva, Leonardo Peres


    An evaluation of the dose distribution received by all the workers involved on coronary angioplasty, arteriography, coronary angiography and mitral valvuloplasty procedures has been made in this work. For the measurements, LiF:Mg, Ti TLD(TLD 100) was used, located in seven different points on the worker's body: hands, knees, neck, forehead and thorax, inside and outside lead apron.) The measurements have been done for each hemo dynamical procedure, and the TLD calibrated in personal dose equivalent (H{sub p}(d)) operational quantity for 0,07 mm, 3 mm and 10 mm depth. Nurses and auxiliary doctors did not receive expressive dose values, indicating that the adopted radioprotection procedures seem to be appropriate and sufficient for them. However, the same is not true for the doctors direct in charge of the procedure. The results show the importance of the use of thyroid protections in these cases. This work discusses the main factors that cause occupational dose increase. From all interventionist hemo dynamical procedures analyzed, the dose values received by the doctors on coronary angioplasty procedures and coronary angiography were higher than the ones found on arteriography and mitral valvuloplasty. The higher dose values has been found for coronary angiography procedures in X-ray tools, that work with fluoroscopy on continuous mode and have been executed with brachial way, even in the eyes, hands, knees and thyroid, with or without shield. Multiplying these high dose values, measured in one procedure by the mean number of annual procedures made at the studied hospital by each doctor, the individual dose annual limits can be surpassed. Based on these estimations, some optimizations suggestions have been made and one discussion about the need of additional monitoring points is presented. Different algorithms have been used in order to estimate the effective dose, including a new proposal. The obtained results using the actual Radiodiagnostic Brazilian

  14. Health providers' perception of quality of care for neonates in health facilities in a municipality in Southern Ghana. (United States)

    Elikplim Pomevor, Kokui; Adomah-Afari, Augustine


    Purpose The purpose of this paper is to assess available human resources for neonatal care and their skills, in order to explore health providers' perceptions of quality of neonatal care in health facilities in Ghana. Design/methodology/approach Data were gathered using qualitative interviews with health providers working in the maternity and paediatric wards and midwives; direct observation; and documentary review at a regional hospital, a municipal hospital and four health centres in a municipality in a region in Southern Ghana. Data were analysed using thematic framework through the process of coding in six phases to create and establish meaningful patterns. Findings The study revealed that health providers were concerned about the number of staff available, their competence and also equipment available for them to work more efficiently. Some essential equipment for neonatal care was either not available or was non-functional where it was available, while aseptic procedures were not adhered to. Moreover, personal protective equipment such as facemask, caps, aprons were not used except in the labour wards where staff had to change their footwear before entering. Research limitations/implications Limited number of health providers and facilities used, lack of exploration of parents of neonates' perspective of quality of neonatal care in this study and other settings, including the teaching hospitals. The authors did not examine issues related to the ineffective use of IV cannulation for neonates by nurses as well as referral of neonates. Additionally, the authors did not explore the perspectives of management of the municipal and regional health directorates or policy makers of the Ministry of Health and Ghana Health Service regarding the shortage of staff, inadequate provision of medical equipment and infrastructure. Practical implications This paper suggests the need for policy makers to redirect their attention to the issues that would improve the quality of

  15. 云南省玉米种子带菌检测及种衣剂处理的生物学效应%Testing of Seed Borne Fungi of Major Corn Varieties from Yunnan Province and Effect of Seed Coating Treatment with Different Formulations

    Institute of Scientific and Technical Information of China (English)

    李健强; 刘西莉; 朱春雨; 罗军; 朱建军; 李小林; 浦恩堂; 张松


    This study reported the testing of seed borne fungi of major corn varieties from Yunnan province and effect of seed coating treatment with four different formulations by means of petri-dish testing and field experiment.The results showed that Penicillium, Rhizopus, Paecilomyce, and Trichoderma were main seed borne fungi on the surface of 3 major corn variesties from Yunnan province; Helminthosporium, Rhizopus, Fusarium, and Penicillium represented main seed borne fungi inside. Nigrospora, Alternaria, and Phoma were minor seed borne fungi. The fungi on the seed surface and inside expressed significantly difference among experimental varieties. 20% Carbofuran-Thiram seed coating formulation (specific for corn seed coating treatment) provided a good control for seed borne fungi, increased seed germination and seedling emergence. Apron and Celest treatment expressed obvious sound seedling.%采用平皿测定方法和田间小区试验对云南省3个主栽玉米品种分别进行了种子带菌检测和4种不同种衣剂包衣处理的生物学效应研究。结果表明,玉米种子表面携带的优势菌群主要为青霉菌(Penicillium)、根霉菌(Rhizopus)、瓶梗青霉菌(Paecilomyces)和木霉菌(Trichoderma);种子内部寄藏的真菌主要有长蠕孢菌(Helminthosporium)、根霉菌(Rhizopus)、镰刀菌(Fusarium)和青霉菌(Penicillium),其它分离频率较高的寄藏真菌还有黑孢霉菌(Nigrospora)、交链孢菌(Alternaria)和茎点霉菌(Phoma)等;种子表面和内部携带真菌种类在品种之间有较大差异。20%克福种衣剂对种子带菌消毒、提高发芽和出苗率效果显著;Apron和Celest在促进壮苗方面具有良好的作用。

  16. Observations of ice-exposing impacts in the Martian mid-latitudes (United States)

    Dundas, C. M.; Byrne, S.; McEwen, A. S.


    The Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment (HiRISE) and Context Camera (CTX) have observed the sites of hundreds of new impacts on the Martian surface. Impacts in the northern mid-latitudes have excavated ice [1], allowing a new approach to studying the Martian cryosphere via active surface processes. HiRISE has systematically monitored these sites to characterize their morphology and changes over time. We will discuss the morphology, distribution and implications of the icy craters observed in this campaign. At the time of writing, ice has been excavated at thirteen impact sites at middle to high northern latitudes. (Detection of impacts is strongly biased towards dusty areas, where large dark blast zones form during impact; due to this bias, impacts are rarely detected in the southern mid-latitudes.) The crater observations indicate that the latitudinal and depth distribution of ice-exposing impacts is in general agreement with models of ice stability [e.g. 2], with ice visible in most craters above 43° N and absent below. A handful of small craters at high latitude do not show visible ice. While the lower-latitude icy impact sites may be closer to the equator than the current stability boundary [1], this boundary is expected to vary over time and extant ice could be a remnant of previous climatic conditions, particularly in exposures associated with lobate aprons. The ice, initially bright, is observed to fade over time, eventually matching the surrounding regolith over a period of months to years. Ice remains visible over a period of months, while as much as millimeters of sublimation occurs [3,4]; the ice must be clean rather than pore-filling. While some clean ice might be produced by melting and refreezing during impact, little or no melting is expected in the smaller craters [5], suggesting that the ice originally had a low regolith content. Such excess ice was observed by the Phoenix lander [6], and our observations suggest

  17. Resurfacing history of the Harmakhis Vallis channel, Mars (United States)

    Kukkonen, Soile; Kostama, Veli-Petri


    Harmakhis Vallis is one of the four major outflow channel systems (Dao, Niger, Harmakhis and Reull Valles) which cut the eastern rim region of the Hellas basin, the largest well-preserved impact structure of Mars. The structure of Harmakhis Vallis and the volume of its head depression, as well as the earlier dating studies suggest that the channel formed during the Hesperian period by collapsing when a large amount of subsurface fluids was released. Thus Harmakhis Vallis, as well as the other nearby outflow channels, represent a significant stage of the fluvial activity in the regional history. On the other hand, the channel lies on the Martian mid-latitude zone, where there are several geomorphologic indicators of past and possibly also contemporary ground ice. The floor of Harmakhis also displays evidence of a later-stage ice-related activity as the channel has been covered by lineated valley fill deposits and debris apron material.The eastern rim region of the Hellas impact basin has been the subject of numerous geologic mapping studies at various scales and using different imaging data sets. However, the Harmakhis Vallis channel itself has received less attention, or the studies on the channel have focused only on different geologic events as a separate subject. In this work, we present our mapping and dating results of the Harmakhis Vallis floor based on the Mars Reconnaissance Orbiter's ConTeX camera imagery (CTX; ~5 m/pixel), which covers the entire Harmakhis channel system from its head depression to the beginning of the terminus. The purpose of the study is to outline how the floor of the Harmakhis Vallis channel has been modified after its formation, what kind of geologic processes have occurred on the channel and when, and by doing so, provide further understanding of the channel evolution and changes in the Martian climate. This work also gives information about the crater counting age determination method and its usability in the cases where only high

  18. Digital photogrammetry and GIS-based analysis of the bio-geomorphological evolution of Sakurajima Volcano, diachronic analysis from 1947 to 2006 (United States)

    Gomez, Christopher


    top of the lava deposits and in between lava deposit to accumulate mid-slopes, rather than accumulating on the lower volcanic apron. This is accentuated by the construction of SABO dams that keep a large amount of the material on the slopes. Finally, as this publication has been carried out using the freely available imagery from the GSI (Geospatial Information Authority of Japan) at 200 dpi, higher resolution imagery can even open further possibilities for the monitoring of volcano evolution in Japan and in countries providing long series of historical imagery.

  19. The Martain drainage system and the origin of valley networks and fretted channels (United States)

    Carr, Michael H.


    Outflow channels provide strong evidence for abundant water near the Martian surface and an extensive groundwater system. Collapse of the surface into some channels suggests massive subsurface erosion and/or solution in addition to erosion by flow across the surface. Flat floors, steep walls, longitudinal striae and ridges, downstream deflection of striae from channel walls, and lack of river channels suggest that fretted channels form dominantly by mass wasting. A two-stage process is proposed. In the first stage, extension of valleys heads is favored by seepage of groundwater into debris shed from slopes. The debris moves downstream, aided by interstitial groundwater at the base of the debris, possibly with high pore pressures. In the second stage, because of climate change or a lower heat flow, groundwater can no longer seep into the debris flows in the valleys, their movement almost stops, and more viscous ice-lubricated debris aprons form. Almost all uplands at elevations greater than +1 km are dissected by valley networks, although the drainage densities are orders of magnitude less than is typical for the Earth. The valley networks resemble terrestrial river systems in planimetric shape, but U-shaped and rectangular-shaped cross sections, levee- like peripheral ridges, median ridges, patterns of branching and rejoining, and flat floors without river channels suggest that the networks may not be true analogs to terrestrial river valleys. It is proposed that they, like the fretted channels, formed mainly by mass wasting, aided by groundwater seepage into the mass-wasted debris. Movements of only millimeters to centimeters per year are needed to explain the channel lengths. Most valley formation ceased early at low latitudes because of progressive dehydration of the near surface, the result of sublimation of water and/or drainage of groundwater to regions of lower elevations. Valley formation persisted to later dates where aided by steep slopes, as on crater

  20. Multiple edifice-collapse events in the Eastern Mexican Volcanic Belt: The role of sloping substrate and implications for hazard assessment (United States)

    Carrasco-Nunez, Gerardo; Diaz-Castellon, Rodolfo; Siebert, L.; Hubbard, B.; Sheridan, M.F.; Rodriguez, Sergio R.


    The Citlalte??petl-Cofre de Perote volcanic chain forms an important physiographic barrier that separates the Central Altiplano (2500??masl) from the Gulf Coastal Plain (GCP) (1300??masl). The abrupt eastward drop in relief between these provinces gives rise to unstable conditions and consequent gravitational collapse of large volcanic edifices built at the edge of the Altiplano. Eastward sloping substrate, caused by the irregular configuration of the basement rocks, is the dominant factor that controls the direction of collapsing sectors in all major volcanoes in the region to be preferentially towards the GCP. These collapses produced voluminous debris avalanches and lahars that inundated the well-developed drainages and clastic aprons that characterize the Coastal Plain. Large catastrophic collapses from Citlalte??petl, Las Cumbres, and Cofre de Perote volcanoes are well documented in the geologic record. Some of the avalanches and transformed flows have exceptionally long runouts and reach the Gulf of Mexico traveling more than 120??km from their source. So far, no direct evidence has been found for magmatic activity associated with the initiation of these catastrophic flank-collapses. Apparently, instability of the volcanic edifices has been strongly favored by very intense hydrothermal alteration, abrupt topographic change, and intense fracturing. In addition to the eastward slope of the substrate, the reactivation of pre-volcanic basement structures during the Late Tertiary, and the E-W to ENE-SSW oriented regional stress regimes may have played an important role in the preferential movement direction of the avalanches and flows. In addition to magmatic-hydrothermal processes, high amounts of rainfall in the area is another factor that enhances alteration and eventually weakens the rocks. It is very likely that seismic activity may be the principal triggering mechanism that caused the flank collapse of large volcanic edifices in the Eastern Mexican Volcanic

  1. Muddy conditions reduce hygiene and lying time in dairy cattle and increase time spent on concrete. (United States)

    Chen, Jennifer M; Stull, Carolyn L; Ledgerwood, David N; Tucker, Cassandra B


    Dairy cattle spend less time lying and show signs of increased stress when housed in rainy and windy conditions, but no work has separated the effects of exposure to inclement weather from muddy conditions underfoot. Our objective was to evaluate the effects of muddy conditions alone on lying behavior, hygiene, and physiological responses. We housed pairs of pregnant, nonlactating dairy cattle (n = 12; 6 primigravid heifers, 6 multiparous cows) in enclosed pens with dirt floors and a concrete feed apron. Cattle were exposed to 3 levels of soil moisture: 90 (dry), 74 (muddy), or 67% (very muddy) dry matter for 5 d each in a replicated 3 × 3 Latin square design. Lying time was measured on all days with data loggers, and lying locations and postures were recorded on the final day of each treatment. Before and after each treatment, blood samples were collected, and the percentage of dirty surface area was measured on the udder, hind leg, and side of each animal. Cattle spent less time lying down in muddier conditions, especially in the first 24 h of exposure, when cows and heifers spent only 3.2 and 5.8 h, respectively, lying down in the muddiest treatment compared with 12.5 and 12.7 h on dry soil. When the soil was dry, cattle never chose to lie down on concrete, but in muddier conditions they spent a greater proportion of their lying time on concrete (mean ± SE: 56 ± 14 and 10 ± 8% in the very muddy and muddy treatments, respectively). The shift in lying location was more marked for heifers, and all 6 spent ≥87% of their lying time on concrete in the muddiest treatment. When cattle chose to lie down on wetter soil, they limited the surface area exposed to their surroundings by tucking their legs beneath their bodies (mean ± SE: 30 ± 11, 15 ± 4, and 5 ± 2% of lying observations in the very muddy, muddy, and dry treatments, respectively). Despite cattle spending less time on wetter soil, all 3 measured body parts became dirtier in muddier conditions (1.4-, 1

  2. 温室作业女性菜农月经周期异常的影响因素%Influencing factors to abnormal menstrual cycle of female farmers engaged in greenhouse operations

    Institute of Scientific and Technical Information of China (English)

    任有勋; 阎少妹; 邢杰; 李万伟; 赵健; 郑重; 翟庆峰; 邱玉刚


    目的 探讨引起女性菜农月经周期异常的主要影响因素,为促进菜农生殖健康提供线索和依据.方法 以寿光地区从事蔬菜种植作业的248名妇女为调查对象进行问卷调查.采用SPSS 17.0软件进行月经周期异常的单因素分析及多因素logistic回归分析.结果 单因素分析显示:有无家族病史、喷洒农药天数、喷洒农药时是否穿着围裙或长衣、橡胶手套、冬季施药后隔多久洗澡、乳房胀痛、乏力、烦躁不安、腹痛、孕次、孕期工作月数、乳腺疾病、子代数、宫内胎儿是否正常、同房频率是否正常、有无流产等均与女性菜农的月经周期异常有关,均P <0.05.进行二分类的logistic回归分析,最终得到喷洒农药天数、施药是否带口罩、是否穿着围裙或长衣、冬季施药后隔多久洗澡、月经前有无乏力、月经前有无腹痛、有无阴道疾病、怀孕时宫内胎儿发育是否正常8个有统计学意义的因素.结论 8项与温室蔬菜作业妇女生殖卫生可能有关的危险因素的确定,为进一步深入研究和分析提供了线索.加强女性菜农的健康教育和月经期卫生保健工作分很有必要.%[Objective]To explore the causes of female farmers' menstrual cycle abnormalities, and provide clues and evidence for promotion of farmers' reproductive health. [Methods] A total of 248 female farmers engaged in greenhouse operations in Shouguang area were selected as subjects for questionnaire survey. SPSS17.0 software was sued for univariate analysis and multivariate logistic regression analysis of menstrual cycle abnormalities. [Results] Univariate analysis showed that there were many factors associated with the female menstrual cycle abnormalities: family history of the disease, the days of pesticide spraying, whether wearing apron or long coats and rubber gloves or not in pesticide spraying, the period to take a shower after spraying in winter, breast

  3. Submarine Landslides at Santa Catalina Island, California (United States)

    Legg, M. R.; Francis, R. D.


    Santa Catalina Island is an active tectonic block of volcanic and metamorphic rocks originally exposed during middle Miocene transtension along the evolving Pacific-North America transform plate boundary. Post-Miocene transpression created the existing large pop-up structure along the major strike-slip restraining bend of the Catalina fault that forms the southwest flank of the uplift. Prominent submerged marine terraces apparent in high-resolution bathymetric maps interrupt the steep submarine slopes in the upper ~400 meters subsea depths. Steep subaerial slopes of the island are covered by Quaternary landslides, especially at the sea cliffs and in the blueschist metamorphic rocks. The submarine slopes also show numerous landslides that range in area from a few hectares to more than three sq-km (300 hectares). Three or more landslides of recent origin exist between the nearshore and first submerged terrace along the north-facing shelf of the island's West End. One of these slides occurred during September 2005 when divers observed a remarkable change in the seafloor configuration after previous dives in the area. Near a sunken yacht at about 45-ft depth where the bottom had sloped gently into deeper water, a "sinkhole" had formed that dropped steeply to 100-ft or greater depths. Some bubbling sand was observed in the shallow water areas that may be related to the landslide process. High-resolution multibeam bathymetry acquired in 2008 by CSU Monterey Bay show this "fresh" slide and at least two other slides of varying age along the West End. The slides are each roughly 2 hectares in area and their debris aprons are spread across the first terrace at about 85-m water depth that is likely associated with the Last Glacial Maximum sealevel lowstand. Larger submarine slides exist along the steep Catalina and Catalina Ridge escarpments along the southwest flank of the island platform. A prominent slide block, exceeding 3 sq-km in area, appears to have slipped more than

  4. Geology of Joshua Tree National Park geodatabase (United States)

    Powell, Robert E.; Matti, Jonathan C.; Cossette, Pamela M.


    and basins in the Park exhibit an east-west physiographic grain controlled by left-lateral fault zones that form a sinistral domain within the broad zone of dextral shear along the transform boundary between the North American and Pacific plates. Geologic and geophysical evidence reveal that movement on the sinistral faults zones has resulted in left steps along the zones, resulting in the development of sub-basins beneath Pinto Basin and Shavers and Chuckwalla Valleys. The sinistral fault zones connect the Mojave Desert dextral faults of the Eastern California Shear Zone to the north and east with the Coachella Valley strands of the southern San Andreas Fault Zone to the west.Quaternary surficial deposits accumulated in alluvial washes and playas and lakes along the valley floors; in alluvial fans, washes, and sheet wash aprons along piedmonts flanking the mountain ranges; and in eolian dunes and sand sheets that span the transition from valley floor to piedmont slope. Sequences of Quaternary pediments are planed into piedmonts flanking valley-floor and upland basins, each pediment in turn overlain by successively younger residual and alluvial surficial deposits.

  5. The impact of human activities in africa,the north and south pole regions on global climate change (United States)

    Abubakar, Babagana

    a way that goals could be achieved without necessarily causing problems to the world climate. 4. The International Maritime Organization (IMO) should check and control the Ocean Pollutions caused as a result of the degreasing activities of the "QUAY APRONS" currently going on at the various African Sea Ports in order to protect the Ocean pollution with chemicals that can make the World's ice to be melting. 5. The International Meteorological Organization should open its offices within each region of the six continents in order to have a closer monitoring of human activities that can influence the world's climate. 6. Organizing seminars, Conferences and Workshops on a regular basis by the United Nations and other related organizations can help in the areas of public enlightenment and the education of the rural populace who are also great contributors to the situation. 7. The UN should use its capacity to discourage the importation of fairly used refrigerators, Air-conditioners and propellants to Africa and at the same time assist in the subsidy of the newer ones coming to Africa, so that the average African can afford buying them I believe that if the above listed suggestions/recommendations are adopted and implemented it will help in reducing these challenges threatening the entire world. Thanks for listening.

  6. The Mountains of Io: Global and Geological Perspectives from Voyager and Galileo (United States)

    Schenk, Paul; Hargitai, Henrik; Wilson, Ronda; McEwen, Alfred; Thomas, Peter; Bredekamp, Joe (Technical Monitor)


    the lower crust induced by global subsidence might be reduced, encouraging volcanism and discouraging mountain building. In regions of mantle downwelling, these compressive stresses in the lower crust might be increased, discouraging volcanism and encouraging mountain building. Alternatively, the global pattern may be related to possible (but undocumented) nonsynchronous rotation of lo, which would produce two regions each of compression and extension in the crust. Evidence of layering and of mass wasting, including landslides, block sliding, debris aprons and downslope creep, on Ionian mountains suggests that the crust of Io is essentially a layered stack of partially consolidated volcanic lavas and plume deposits, becoming more consolidated with depth. The lower crust especially may also be ductily deformed, punctuated by volcanic intrusions and faulting at paterae, and broken into blocks, some of which have been uplifted to form mountains.

  7. Re-analysis of martian gully orientation and slope for comparison with climate model predictions of freeze-thaw and dry-ice sublimation. (United States)

    Conway, Susan; Harrison, Tanya; Lewis, Stephen; Balme, Matthew; Soare, Richard; Britton, Andrew


    Gullies on Mars are kilometre-scale landforms, comprising an erosional alcove and channel and a terminal debris apron/fan. These landforms are similar to features on Earth carved by the flow of liquid water, or by the action of water rich debris flows. The majority gullies on Mars are believed to be (at most) ˜5 Ma old and both erosion and deposition within these features have been observed within the last 10 years of orbital observations. At present liquid water is not thermodynamically stable at the martian surface and many of the recent changes in surface morphology occur during winter and early spring, when temperatures are too low for even metastable liquid water to be produced. Therefore, researchers have proposed an alternative mechanism for gully-formation - the sublimation of solid CO2, which is deposited on the maritan surface every winter. Previous studies have revealed that gully-density and orientation varies systematically with latitude - a fact that led to the development of many climate-based hypotheses for their formation. Here, we use the global database of martian gullies and extract the orientation and slope-angle of gully-hosting-slopes. We find that gully-orientation is more even strongly controlled by latitude than previous studies, where more sparse data were used. From ˜30-40° latitude in both hemispheres, gullies are almost never found on equator-facing slopes, and polewards of 40° gullies have a tendency to be located on equator-facing slopes. We use a 1D version of the LMD Mars climate model physics to simulate surface temperature on slopes up to 35° , oriented to face north or south, for all latitudes (5° spacing), and for orbital obliquities of 5-55° . We otherwise use current orbital conditions (ellipticity, date of perihelion) and we use a constant thermal inertia of the substrate of 1000 Jm-2K-1s-1/2and a bare soil albedo of 0.2. We extracted two pieces of information from a complete annual cycle: (i) The number of hours

  8. The Rise and Fall of a Surtseyan Volcano: 2005 AD Eruption of Ambae (vanuatu, Sw-Pacific (United States)

    Nemeth, K.


    On November 27th 2005 vapour plumes and minor ash columns emerged from the summit of Ambae. By the 3rd December, subaqueous explosive eruptions were confirmed in Lake Vui caldera lake and an island ~10 m high and ~100 m long emerged. Every 30 seconds an explosion took place, forming dense "cock's-tail" jets of steaming rock debris up to ~100 m high. These jets were initially black, but the condensing steam turned the clouds white as they collapsed back into Lake Vui, forming base surges that travelled with a speed of ~50-100 m/s over not more than 200 m from the vent. Debris jets were charged with water and mud and appeared to contain only rare large (jets were vertical and ejected material fell back commonly into the vent zone. Base surges formed especially after larger eruptive bursts, and travelled about 150 m away from their source before stalling. By the 8th December, a tephra apron (~70 m high) had grown to form an elliptical island, which was still open to the caldera lake. Since 5th December, the vent zone had shifted north-westward by 100-150 m. Eruptions still emanated from a subaqueous vent. Along with the debris jets, subaqueous pyroclastic density current activity continued on a larger scale than before, generating surface waves on the lake with amplitudes of ~1 m. The connection between the crater and caldera lake was maintained by subaqueous mass-wasting of the edifice. Larger explosive events initiated pyroclastic surges that covered the whole growing tuff cone. By the 12th December, the frequency of the individual explosions had dropped (3-5 per minute). They were more energetic, forming higher plumes reaching >200 m in height and containing large amounts of juvenile pyroclasts. The tuff cone had reached ~100 m in height by this time in its western rim. On the 13th December, energetic surges were witnessed that travelled 2-3 times farther than during the initial phase of the eruption, reaching at least 300 m from the vent. After the 13th December

  9. Hygiene aspects of cosmetic services

    Directory of Open Access Journals (Sweden)

    Anita Kukułowicz


    epidermidis was observed and present in more than 30% of bowls for soaking feet and on the hands of beauticians in over 60% of the samples. 2 All tested areas were marked by the presence of fungi and yeasts, and a number of aerobic, mesophilic microorganisms. 3 Among the analyzed surfaces, the most contaminated were bowls for soaking feet. 4 The most contaminated with the mesophilic bacteria were samples taken from the hands of beauticians, of which almost 70% obtained only sufficient score; more than 30% of samples taken from the surfaces of aprons obtained the same score. 5 Nearly 20% of samples taken from towels received the excelled grade, depending on the total number of microorganisms, while the very good grade was given to 50% of tests taken from the covers of the chair used for face treatments and, again, to 50% of samples from towels.

  10. 大型桥梁冲刷防护工程损坏特性研究%Study on failure characteristics of scour protection engineering of large bridges

    Institute of Scientific and Technical Information of China (English)

    高正荣; 杨程生; 唐晓春; 俞竹青


    Taking Sutong Bridge as an example, long-term monitoring on scour protection engineering and riverbed terrain and model test are applied to study the failure mechanism of scour protection engineering. The results show that there are two forms of failure in scour protection for large bridges in tidal reach, which are erosion on surface and collapse of slope of aprons;and they usually occur in 1 to 2 years after engineering acceptance. Damage rate and steady slope are suggested for failure index for two forms of failure respectively. Meanwhile, shaping security reference line is proposed based on results of long-term monitoring. When the size of protection engineering is less than the shaping security reference line, failure would take place. Moreover, the results also show that changes of protection zone are caused by sediment erosion or siltation on surface after engineering adapted with surrounding current and terrain; and these changes have no significant effect on stability of protection engineering. The research results can provide references for bridge design and related studies.%以苏通大桥为例,通过模型试验和冲刷防护工程及周边河床地形的长期监测开展了大型桥梁冲刷防护工程的损坏特性研究。研究结果表明,大型桥梁冲刷防护工程存在两种损坏形式:防护工程防护区面层冲刷损坏和防护工程护坦边坡坍塌损坏;防护工程的破坏主要发生在防护工程后1~2年内。提出了以“损坏率”和“稳定边坡”分别表示两种不同类型的破坏指标。同时,提出了防护工程“成型稳定工程量基准线”概念,为监测冲刷防护工程稳定性制定定量目标。研究结果还表明,在防护体稳定后,防护区呈“洪季淤积、枯季冲刷”特点,这一变化对防护体稳定影响有限。研究结果为类似工程设计、监测、维护和相关研究提供参考。

  11. The stratigraphy of cretaceous mudstones in the eastern Fuegian Andes: new data from body and trace fossils Estratigrafía de las fangolitas del Cretácico en los Andes Fueguinos orientales: Nuevos datos de cuerpos y trazas fósiles

    Directory of Open Access Journals (Sweden)

    Eduardo B. Olivero


    Full Text Available The stratigraphy of Cretaceous marine mudstones in the Fuegian Andes, roughly equivalent to Charles Darwin's clay-slate formation, remains a still unsolved problem. Previous records of Albian, Turonian-Coniacian, and Santonian-Campanian bivalves are combined with new findings of the Late Albian inoceramid Inoceramus anglicus Woods, and the Maastrichtian ammonites Diplomoceras sp., Anagaudryceras sp., Maorites densicostatus (Kilian and Reboul, Maorites sp., and Pachydiscus (Neodesmoceras sp. to further constrain the Cretaceous stratigraphy of the eastern Fuegian Andes. In addition, new records of distinctive trace fossils and ichnofabric are meaningful for stratigraphic division and delineation of paleoenvironmental settings in these Cretaceous mudstones. The Lower Cretaceous ichnoassemblage of Chondrites targioni (Brongniart and Zoophycos isp. is consistent with the inferred slope-volcaniclastic apron settings of the Yahgan Formation; Nereites missouriensis (Weller reflects distal basin plain depositional settings for the Beauvoir Formation. In the Upper Cretaceous, the "Estratos de Buen Suceso" record the earliest extensively bioturbated horizons, reflecting prolonged well-oxygenated bottom conditions. In the Bahía Thetis Formation, organic-rich, channel margin or distal basin slaty mudstones record the last occurrence of inoceramid bivalves in the Austral Basin; the generalized absence of trace fossils is consistent with dysoxic bottom conditions. The thoroughly bioturbated Policarpo Formation, records a marked change in paleoceanographic conditions. The strong contrast in the intensity of bioturbation between the Upper Campanian-Maastrichtian Bahía Thetis Formation, almost devoid of trace fossils, and the highly bioturbated Maastrichtian-Danian Policarpo Formation reflects a change from dysoxic-anoxic to well ventilated conditions, probably associated with a cooling trend of bottom waters in the austral deep oceans.En los Andes Fueguinos la

  12. 基于 ANSYS 的软体排动水沉排受力分析%ANSYS-based Analysis on Actions of Compound Geotextile Being installed in Dynamic Water

    Institute of Scientific and Technical Information of China (English)

    张益智; 张焕岭; 许战军


    软体排因其排布具有隔离、反滤作用及整体具有一定的柔性可适应凹凸不平的地形,材料使用寿命长、施工方便等特点,被广泛应用于河道的护底及护岸、海岸的护滩、泄水建筑物后部的防冲等。在软体排施工中,为了防止沉排时因受力过大导致排体撕裂、铺排船倾覆等的发生,要严格控制软体排船舷处拉力。对于静水中沉排时软体排船舷处拉力的研究,已基本趋于成熟化,有精确的解析解,但对动水中沉排时软体排拉力多采用试验方法得出经验公式来计算。文章在静水中沉排时软体排受力基础上建立动水中软体排计算有限模型,并通过具体算例得出动水中软体排拉力变化的一些规律。%The soft geotextile is widely utilized for bottom protection of river course, river bank protection, sea bank apron and scouring pro-tection of the rear sections of outlet structures as it can play the roles of isolation, filter and flexibility which can satisfy the uneven landforms. This geotextile also features long service life and construction convenience.The tension on the geotextile at shipboard shall be controlled strictly in the geotextile installation so as to avoid the geotextile being torn up or the ship being overturned because of the large tension while the geotextile is being installed.The study on the tension at the shipboard while the geotextile is installed in the static water is becoming ma-ture and precise analysis and calculations are available.But the tension at the shipboard while the geotextile is installed in the dynamic water is calculated by applying the empirical formula which is from test methods.In this paper, the finite element model for calculation of the soft geotextile installation in the dynamic water is constructed based on the action on the geotextile being installed in the static water.Through specific calculation, some laws on variation of action on the

  13. An Olivine-Rich Crater in Tyrrhena Terra (United States)


    This image of the ejecta of a crater in the Tyrrhena Terra region was taken by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) at 0328 UTC on February 23, 2007 (10:28 p.m. EST on February 22, 2007), near 13 degrees south latitude, 67 degrees east longitude. CRISM's image was taken in 544 colors covering 0.36-3.92 micrometers, and shows features as small as 18 meters (60 feet) across. The region covered is roughly 9 kilometers (5.6 miles) wide at its narrowest point. Named for a classic albedo feature, Tyrrhena Terra is an extensive, heavily-cratered part of Mars' southern highlands, some 2,300 kilometers (1,430 miles) at its broadest extent. It is located to the northeast of the Hellas basin. The region imaged by CRISM is to the north of Hellas Planitia and just east of the crater Huygens in Tyrrhena Terra's western end. The uppermost image in the montage above reveals the location of the CRISM image on a mosaic taken by the Mars Odyssey spacecraft's Thermal Emission Imaging System (THEMIS). The CRISM image is located inside a large, flat-floored crater measuring about 52 kilometers (32 miles) across. The image includes a small crater and its ejecta blanket, an apron of material thrown out during a crater's formation, both located inside the larger crater. The lower left image is an infrared false-color image that reveals the extent of the ejecta blanket. It also includes ejecta from another small crater located just east of the CRISM image. The lower right image shows the strengths of mineral absorptions, and reveals the composition of the ejecta and surrounding material. The ejecta surrounding the small impact crater is thickest at the crater's rim, and becomes thinner to discontinuous at the blanket's outer edge. This small crater's ejecta blanket shows an enhanced spectral signature of the mineral olivine, as does the ejecta from the small crater just out of view to the east. In contrast the surrounding material is rich in the volcanic mineral

  14. Development of composite materials for non-leaded glove for use in radiological hand protection (United States)

    Dodoo-Amoo, David Nii Amoo

    that this new composite material could also replace the lead aprons currently in use, as shields against radiation like x-ray in most hospitals. Based on computational and experimental results, the recommended compositions of the composite materials for the glove are: (i) Erbium III Oxide (Er2O3)---40% and 40 Tungsten Boride (WB) blend with 20% Neoprene formulation, or with the reduced Er2O3, (ii) Erbium III Oxide (Er2O 3)---5% and 75% Tungsten Boride (WB) blend with 20% Neoprene formulation. (iii) Tungsten III Oxide (WO3)---80% blended with 20% Neoprene formulation. Toxicity Characteristic Leaching Procedure (TCLP) results show that, several heavy metals used in these new materials that would leach out were below the US EPA limit or are not on the list of regulated heavy metals. However, on the original gloves Lead leached out at a concentration of 5.2 mL/L, slightly above the regulatory limit.

  15. A field study of the geomorphic effects of sublimating CO2 blocks on dune slopes at Coral Pink Dunes, Utah. (United States)

    Bourke, Mary; Nield, Jo; Diniega, Serina; Hansen, Candy; McElwaine, Jim


    The seasonal sublimation of CO2 ice is an active driver of present-day surface change on Mars. Diniega et al (2013) proposed that a discrete type of Martian gully, found on southern hemisphere dunes, were formed by the movement of CO2 seasonal ice blocks. These 'Linear Gullies' consist primarily of long (100 m - 2.5 km) grooves with near-uniform width (few-10 m wide), and typical depth of Pink sand dunes, Utah. These are sister experiments to those undertaken in Arizona (Bourke et al, 2016). The experiments were undertaken on an active barchan dune with a 16 m long lee slope (30.3°). Ambient air temperature was 30°C and relative humidity was 25%; sand surface temperatures were 26.5°C. A CO2 ice block (60x205x210 mm) was placed at the dune brink and with a gentle nudge it moved downslope. The dynamics of the block movement were recorded using a pair of high resolution video cameras. Geomorphological observations were noted and topographic change was quantified using a Leica P20 terrestrial laser scanner with a resolution of 0.8 mm at 10 m, and change detection limits less than 3 mm. The block run was repeated a total of 10 times and launched from the same location at the dune brink. The experiment ran for 45 minutes. The block size was reduced to (45 x 190 x 195 mm) by the end of the run series. The resultant geomorphology shows that the separate block runs occupied different tracks leading to a triangular plan form shape with a maximum width of 3.5 m. This is different from the findings in Arizona where a narrower track span was recorded (1.7m) (Bourke et al, 2016). Similar block dynamics were observed at both sites (as blocks moved straight, swiveled and bounced downslope). Distinctive pits with arcuate rims on their downslope edge were formed where blocks bounced on the surface. These pits are at an almost equidistant spacing. Despite a longer slope (16 m as opposed to 8m at Grand Falls), no depositional apron was formed. Levee development was less consistent

  16. Geologyy of the Yucca Mountain Site Area, Southwestern Nevada, Chapter in Stuckless, J.S., ED., Yucca Mountain, Nevada - A Proposed Geologic Repository for High-Level Radioactive Waste (Volume 1)

    Energy Technology Data Exchange (ETDEWEB)

    W.R. Keefer; J.W. Whitney; D.C. Buesch


    Yucca Mountain in southwestern Nevada is a prominent, irregularly shaped upland formed by a thick apron of Miocene pyroclastic-flow and fallout tephra deposits, with minor lava flows, that was segmented by through-going, large-displacement normal faults into a series of north-trending, eastwardly tilted structural blocks. The principal volcanic-rock units are the Tiva Canyon and Topopah Spring Tuffs of the Paintbrush Group, which consist of volumetrically large eruptive sequences derived from compositionally distinct magma bodies in the nearby southwestern Nevada volcanic field, and are classic examples of a magmatic zonation characterized by an upper crystal-rich (> 10% crystal fragments) member, a more voluminous lower crystal-poor (< 5% crystal fragments) member, and an intervening thin transition zone. Rocks within the crystal-poor member of the Topopah Spring Tuff, lying some 280 m below the crest of Yucca Mountain, constitute the proposed host rock to be excavated for the storage of high-level radioactive wastes. Separation of the tuffaceous rock formations into subunits that allow for detailed mapping and structural interpretations is based on macroscopic features, most importantly the relative abundance of lithophysae and the degree of welding. The latter feature, varying from nonwelded through partly and moderately welded to densely welded, exerts a strong control on matrix porosities and other rock properties that provide essential criteria for distinguishing hydrogeologic and thermal-mechanical units, which are of major interest in evaluating the suitability of Yucca Mountain to host a safe and permanent geologic repository for waste storage. A thick and varied sequence of surficial deposits mantle large parts of the Yucca Mountain site area. Mapping of these deposits and associated soils in exposures and in the walls of trenches excavated across buried faults provides evidence for multiple surface-rupturing events along all of the major faults during

  17. 深圳大运中心体育场钢屋盖结构设计若干关键技术研究%Research on several key technologies for structural design of steel-roof of the Shenzhen Universiade Sports Centre

    Institute of Scientific and Technical Information of China (English)

    张建军; 刘琼祥; 刘臣; 郭满良; 彭省华; 杨德喜; 王启文


    A new type of structural system named as single-layer folded-plane latticed shell structure was adopted for the steel roof of main stadium of the Shenzhen Universiade Sports Center.Although there are over 80 tons of massive cast-steel nodes, its good quality is assured since the design was based on finite element analysis and optimization of the joint structure.Both elastic finite element analysis and elasto-plastic finite element analysis on the cast steel spherical joint supports were conducted.This paper proposes a very practical calculation method for the elastic stage by simplifying the contact boundary.For the calculation, it is necessary to ensure a full rotation of the support and take anti-separation measures.Moreover, material comparison among hot-formed steel pipes and inspections to the finished products need to be conducted.From the analysis, it is believed that massive cast-steel nodes are safe and reliable.The ultimate load carrying capacity of the spherical joint support reaches 3.1 time of the design capacity.In the bowl-shell , there are three directional tension fields.The lower part of the hollow ball partially bears the stress in three directions.To fully rotate the support, concave-slots and gaps need to be reserved beforehand.To avoid the occurrence of accidental separation, an apron and center-hole anchor bolts need to be used.In the case that the ratio of inner radius to the wall thickness is 20, a hot-formed steel pipe can be adopted.The Q345GJ steel is preferentially used for the steel plate.According to the inspection results, the indices of the product satisfy the requirements of national standards.%深圳大运中心体育场钢屋盖采用单层折面空间网格结构.80多吨的超大铸钢节点密切结合铸造工艺特点,通过有限元计算分析和节点构造等的优化提高节点质量.对碗盖球的铸钢球铰支座进行包括接触的弹性和弹塑性有限元分析,提出了简化接触边界条件的弹性阶段

  18. Using of Remote Sensing Techniques for Monitoring the Earthquakes Activities Along the Northern Part of the Syrian Rift System (LEFT-LATERAL),SYRIA (United States)

    Dalati, Moutaz

    SAR interferometer show the existence of spectral structures at the same sites. The Arabian plate is moving in a NNW direction, whereas the African plate is moving to the North. The left-lateral motion along the Dead Sea Fault accommodates the difference in movement rate between both plates. The analysis of TM Space Imagery and digital image processing of spectral data show that the lineaments along AL-Ghab graben maybe considered as linear conjunctions accompanied with complex fracturing system. This complex is affected by distance stresses accompanied with intensive forces. The digital image processing of Radar imagery showing the presence of active and fresh faulting zones along the AL-Ghab graben. TM and SAR-DTM data, also showed a gradual color tone and interruptions of linear-ellipse shapes which reflecting the presence of discontinuity contours along the fault zone extension .This features refer to abundance of surface morphological features indicate to Fresh Faults. Recent faulting is expressed as freshly exposed soil within the colluvial apron visible by its light tone color. These indicators had been proved by field checks. Furthermore, the statistic digital analysis of the spectral data show that there are distribution of spectral plumes. These plumes are decreasing in intensity and color contrast from the center of the site to the direction of its edges.

  19. Geologic Map of MTM -40277, -45277, -40272, and -45272 Quadrangles, Eastern Hellas Planitia Region of Mars (United States)

    Bleamaster, Leslie F.; Crown, David A.


    Hellas Planitia comprises the floor deposits of the Hellas basin, more than 2,000 km across and 8 km deep, which is located in the southern hemisphere's cratered highlands and is the largest well-preserved impact structure on the Martian surface. The circum-Hellas highlands represent a significant percentage of the southern hemisphere of Mars and have served as a locus for volcanic and sedimentary activity throughout Martian geologic time. Hellas basin topography has had a long-lasting influence, acting as Mars' deepest and second largest depositional sink, as a source for global dust storms, and as a forcing agent on southern hemisphere atmospheric circulation. The region lies in the Martian mid-latitude zone where geomorphic indicators of past, and possibly contemporary, ground ice are prominent. The highlands north of the basin show concentrations of Noachian valley networks, and those to the east show prominent lobate debris aprons that are considered to be geomorphic indicators of ground ice. Several studies have proposed that Hellas itself was the site of extensive glacial and lacustrine activity. Recent analyses of mineralogical information from Mars Express' OMEGA (Observatoire pour la Mineralogie, l'Eau les Glaces et l'Activite) and Mars Reconnaissance Orbiter's CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) reveal outcrops of hydrated phyllosilicates in the region, strengthening an already strong case for past aqueous activity in and around Hellas basin. Our mapping and evaluation of landforms and materials of the Hellas region from basin rim to floor provides further insight into Martian global climate regimes and into the abundance, distribution, and flux of volatiles through history. Mars Transverse Mercator (MTM) quadrangles -40277, -45277, -45272, and -40272 (lat 37.5 degrees S.-47.5 degrees S., long 270 degrees W.-280 degrees W.) cover the eastern portion of the Hellas basin including the boundary between its floor and rim, the distal

  20. Sedimentology, conodonts, structure, and correlation of Silurian and Devonian metasedimentary rocks in Denali National Park, Alaska: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1996 (United States)

    Dumoulin, Julie A.; Bradley, Dwight C.; Harris, Anita G.


    A sequence of metasedimentary rocks in Denali National Park (Mt. McKinley and Healy quadrangles), previously mapped by Csejtey and others (1992) as unit DOs (Ordovician to Middle Devonian metasedimentary sequence) and correlated with rocks of the Nixon Fork terrane, contains both deep- and shallow-water facies that correlate best with rocks of the Dillinger and Mystic sequences (Farewell terrane), respectively, exposed to the southwest in the McGrath quadrangle and adjacent areas.New conodont collections indicate that the deep-water facies are at least in part of Silurian age, and can be grouped into three broad subunits. Subunit A is chiefly very fine grained, thinly interbedded calcareous, siliceous, and siliciclastic strata formed mostly as hemipelagic deposits. Subunit B is characterized by abundant calcareous siliciclastic turbidites and may correlate with the Terra Cotta Mountains Sandstone in the McGrath quadrangle. Subunit C contains thin-bedded to massive calcareous turbidites and debris flows, locally intercalated with calcareous siliciclastic turbidites. Sedimentary features suggest that subunits B and C accumulated in a fan and (or) slope apron setting. All three subunits contain subordinate layers of altered tuff and tuffaceous sediment. Turbidites were derived chiefly from a quartz-rich continent or continental fragment and a carbonate platform or shelf, with subordinate input from volcanic and (possibly) subduction complex (accretionary prism) sources. Limited paleocurrent data from subunit B turbidites show generally southward transport. Stratigraphic relations between the three subunits are uncertain, although we believe that subunit A is probably the oldest. Shallow-water facies, at least in part of earliest Late Devonian (early Frasnian) age, are exposed locally and were deposited in intertidal to deeper subtidal settings.Reconnaissance structural studies indicate that the most significant of two generations of folds have northerly vergence and

  1. A summary of present-day gully formation and activity on Mars (United States)

    Diniega, Serina; Hansen, Candice; McEwen, Alfred; Dundas, Colin; Byrne, Shane


    Over the past decade, gully activity has been carefully monitored on a range of slopes, including dune slopes [1-3] and crater walls [2-4]. Within the southern mid-latitudes, substantial changes in gully morphology have been observed. On dune slopes, observed activity includes major incision (forming a new channel or expanding an existing channel), changes in channel sinuosity, expansion of alcoves, and deposition of an extensive new apron. On rockier slopes, observed activity has cut new channel segments and small terraces, abandoned other channels, and deposited boulder-rich lobate features. Many of these morphologies have been treated as indicative of fluvial processes. However, long-term monitoring campaigns with High Resolution Imaging Science Experiment (HiRISE) data [2-5] of almost 500 gully locations, have shown that the timing of this current activity is generally correlated with the presence of seasonal frost [1-5]. Moreover, the distribution of seasonal frost on slopes is similar to the orientation distribution of gullies [3,6]. Most seasonal frost is CO2, and this is likely the main cause of current activity. Recent modeling has shown that CO2 sublimation from within the regolith pores would be sufficient to create the types of geomorphology seen within martian gullies [7]. Water frost may be involved in some small-scale activity [5]. Liquid water is unlikely to be relevant, because the abundance of water frost is generally low [8] and melting is difficult. An additional current focus is on the north polar sand sea, where "gullies" (generally lacking a channel) have been observed to form on dune slopes over seasonal and annual timescales. There, we aim to differentiate between either a general aeolian [8] or seasonal frost driver [9,10] for the formation process. For these features, formation timing estimates are often less constrained because HiRISE images are not acquired during fall and winter, due to the polar hood and darkness. Thus, analysis of

  2. Condições de radioproteção dos consultórios odontológicos Radioprotection in dentistry offices

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Batista de Melo


    Aracaju using radiographic examination as a routine, resulting in a final sample of 103 professionals. The results showed that a high percentage of these professionals ignore the current norms (64,1% as well as the technical specifications of their equipment (51,5% ignored the peak kilovoltage and 57,3% the milliamperage of their equipment, besides examining the radiographs visually (67% As positive behaviors, the paralleling technique was preferred by 62,1% and the lead apron was used by 98,1%. We conclude that, despite the limited knowledge about the Guidelines, some measures are being correctly adopted but that the dentists have to be more aware of the necessary protective measures.

  3. Mars: Cold, windy and occasionally unstable (Invited) (United States)

    Byrne, S.; Becerra, P.; Diniega, S.; Dundas, C. M.; Geissler, P.; Hansen, C. J.; McEwen, A. S.; Russell, P. S.; Thomas, N.


    Once considered disappointingly inactive, the surface of Mars is now known to be quite dynamic. Almost ten Mars years of continuous spacecraft monitoring reveals a unique planetary environment where interaction of the surface with solid and gaseous CO2 dominates current activity. The action of liquid water (dominant on Earth) is restricted to rare locations where recurring slope lineae are best explained as flow of brines. The seasonal frost cycle has been studied for decades; however, a wealth of new detail has emerged through recent spacecraft monitoring. Frost sinters into semi-transparent slabs in some locations allowing spring sunlight to penetrate to the base. Basal sublimation produces pressurized gas that jets from weak locations, scours channels in underlying terrain, erodes polar dunes and is responsible for a plethora of transient albedo features. In the mid-latitudes, CO2 frost is now thought to be the driver of mass movements within gullies both in crater walls and dunes. Many examples of mass transport from gully alcoves, through channels and onto debris aprons have been observed to occur at the coldest times when CO2 frost is present. Liquid water may have played a role in gully formation in the past, but it does not in today's activity. Other active slope processes include rock falls, dust avalanching, and perhaps other, slower processes. A small CO2 ice cap precariously persists throughout southern summer buffering atmospheric pressure. Pits litter this cap and observations over 8 Mars years have shown them to expand by several m/yr from ablation. This erosion has prompted speculation of current climate change; however, models exist where ice cap surfaces may regrow in a cyclic manner. Observations suggest that it is climatic variability associated with late-summer global dust storms that allows this regrowth. Although less volatile than CO2, water ice deposits are also changing. Steep cliffs that bound the polar layered deposits (PLD) have been


    Directory of Open Access Journals (Sweden)

    Pompeu Paes Guimarães


    opinion of employees on their role. The  varnishing was the easier activity, less dangerous and less tiring than the others and the grinder was the least preferred, more dangerous and tiring. Was detected high accident rate in the tools production and this affect mainly the fingers region (72%. Was detected in the workers opinion  that the grinder machine is causing major problems in the production activities of tools by the high accidents rates. Thus, the worker satisfaction is compromised, enhanced by the physical fatigue reported after working hours, dissatisfaction with the use of PPE, such as apron and respirator, even if they ceased  51% of accidents.Keywords: Ergonomics, life quality, tools production. DOI:

  5. Amazonian mid- to high-latitude glaciation on Mars: Supply-limited ice sources, ice accumulation patterns, and concentric crater fill glacial flow and ice sequestration (United States)

    Fastook, James L.; Head, James W.


    Crater deposit thicknesses (~50 m) cannot fill the craters in a time period compatible with the interpreted formation times of the Pedestal Crater mantled ice layers. We use a representative obliquity solution to drive an ice flow model and show that a cyclical pattern of multiply recurring layers can both fill the craters with a significant volume of ice, as well as transport debris from the crater walls out into the central regions of the craters. The cyclical pattern of waxing and waning mantling layers results in a rippled pattern of surface debris extending out into the crater interiors that would manifest itself as an observable concentric pattern, comparable in appearance to concentric crater fill. In this scenario, the formation of mantling sublimation till layers seals the accumulating ice and sequesters it from significant temperature variations at diurnal, annual and spin-axis/orbital cycle time scales, to produce ancient ice records preserved today below CCF crater floors. Lack of meltwater features associated with concentric crater fill provides evidence that the Late Amazonian climate did not exceed the melting temperature in the mid- to high-latitudes for any significant period of time. Continued sequestration of ice with time in CCF and related deposits (lobate debris aprons and lineated valley fill) further reduces the already supply-limited polar ice sources, suggesting that there has been a declining reservoir of available ice with each ensuing glacial period. Together, these deposits represent a candidate library of climate chemistry and global change dating from the Late Amazonian, and a non-polar water resource for future exploration.

  6. SHARAD Detection of Subsurface Interfaces in Southern-Central Utopia Planitia (United States)

    Stuurman, C. M.; Brothers, T. C.; Holt, J. W.; Kerrigan, M.; Osinski, G. R.


    Characterising the extent and distribution of subsurface ice in the middle-latitudes of Mars is an ongoing endeavour, with applications to both paleoclimate and future missions. Utopia Planitia has been posited as an ice-rich area by climate models, Gamma-Ray Spectrometer results suggestive of high hydrogen concentrations, and high densities of periglacial and glacial surface morphologies. The SHAllow RADar (SHARAD) instrument on the Mars Reconnaissance Orbiter is a radar sounder which transmits a 15-25 MHz chirped pulse. The data is recorded in the time delay and can be used to map and characterize Mars' subsurface. In the Utopia Planitia region, SHARAD data can potentially constrain modeling efforts, help locate potential water resources for future exploration, and give volumetric constraints on features that were previously only observed in two dimensions. Thus far, most mid-latitudinal reflectors using the SHARAD instrument have been associated with isolated surface morphologies, such as lobate debris aprons, lineated valley fill, and reflectors beneath volcanic flows. Recently, SHARAD radargrams over pedestal craters in the mid-latitudes have also yielded results suggestive of water-ice composition, and a massive, radar-transparent layer has been found in Arcadia Planitia. Overall, however, there has been a dearth of SHARAD evidence suggestive of the massive subsurface ice sheets predicted by climate models. This project analyzed several hundred SHARAD radargrams throughout Utopia Planitia. Subsurface reflectors were detected by visually inspecting radar data and comparing to simulated radargrams that predict off nadir surface echoes that can be confused with subsurface reflections. Regions of high amplitude subsurface reflections that do not appear in the simulated radargrams were thus interpreted as reflectors represenative of geologic contacts. SHARAD analysis revealed several reflectors in the Southern-Central Utopia Planitia region. These reflectors were

  7. Observations of Ice-Exposing Impacts on Mars over Three Mars Years (United States)

    Dundas, C. M.; Byrne, S.; McEwen, A. S.; Mellon, M. T.; Wu, M. R.; Daubar, I.; Saper, L.


    Monitoring of the Martian surface over many years has enabled the detection of new impact craters, primarily in dusty regions where small craters can produce large dark blast zones. At middle and high latitudes, twenty of these impacts have been observed to excavate ground ice. Remarkably, detection of impacts over a period of decades allows us to learn about Martian ice deposition operating over millennia. At the time of writing, twenty new craters have been found to expose ice. Eighteen of these are in the northern hemisphere. These craters are found on lobate aprons, crater ejecta, or typical plains materials. Compared with the original five craters (Byrne et al., 2009, Science 325, 1674-1676), the distribution of craters with visible ice is much broader, both in latitude and longitude. The lowest-latitude icy site is at 39°N. If this ice is stable then modeling suggests that a long-term average atmospheric water vapor content of ~25 precipitable microns is needed to support this distribution of ice. Alternatively, the near-surface humidity (which controls ice stability) could be higher than expected, or the vapor pressure at the ice table could be lower due to salts in the regolith. Combinations of these effects are also possible. Two new ice-exposing craters have been observed in the southern hemisphere, both poleward of 70°S. One is found on an outlier of the South Polar Layered Deposits, while the other is on plains within an ancient impact crater. Ice exposed by the craters stays bright and distinct for months to years. This requires that it have low regolith content, since sublimating ice-cemented soil would quickly become indistinguishable from dry regolith, as seen at the Phoenix landing site (Smith et al., 2009, Science 325, 58-61). Some clean ice may be produced by the impact process; larger craters at a given site are typically icier, consistent with this possibility but also consistent with vertical variations in the ice table. However, blocks of

  8. Paleozoic evolution of active margin basins in the southern Central Andes (northwestern Argentina and northern Chile) (United States)

    Bahlburg, H.; Breitkreuz, C.

    The geodynamic evolution of the Paleozoic continental margin of Gondwana in the region of the southern Central Andes is characterized by the westward progression of orogenic basin formation through time. The Ordovician basin in the northwest Argentinian Cordillera Oriental and Puna originated as an Early Ordovician back-arc basin. The contemporaneous magmatic arc of an east-dipping subduction zone was presumably located in northern Chile. In the back-arc basin, a ca. 3500 meter, fining-up volcaniclastic apron connected to the arc formed during the Arenigian. Increased subsidence in the late Arenigian allowed for the accomodation of large volumes of volcaniclastic turbidites during the Middle Ordovician. Subsidence and sedimentation were caused by the onset of collision between the para-autochthonous Arequipa Massif Terrane (AMT) and the South American margin at the Arenigian-Llanvirnian transition. This led to eastward thrusting of the arc complex over its back-arc basin and, consequently, to its transformation into a marine foreland basin. As a result of thrusting in the west, a flexural bulge formed in the east, leading to uplift and emergence of the Cordillera Oriental shelf during the Guandacol Event at the Arenigian-Llanvirnian transition. The basin fill was folded during the terminal collision of the AMT during the Oclóyic Orogeny (Ashgillian). The folded strata were intruded post-tectonically by the presumably Silurian granitoids of the "Faja Eruptiva de la Puna Oriental." The orogeny led to the formation of the positive area of the Arco Puneño. West of the Arco Puneño, a further marine basin developed during the Early Devonian, the eastern shelf of which occupied the area of the Cordillera Occidental, Depresión Preandina, and Precordillera. The corresponding deep marine turbidite basin was located in the region of the Cordillera de la Costa. Deposition continued until the basin fill was folded in the early Late Carboniferous Toco Orogeny. The basin

  9. Recurrence rate and magma effusion rate for the latest volcanism on Arsia Mons, Mars (United States)

    Richardson, Jacob A.; Wilson, James A.; Connor, Charles B.; Bleacher, Jacob E.; Kiyosugi, Koji


    likely began around 200-300 Ma then first peaked around 150 Ma, with an average production rate of 0.4 vents per Myr. The recurrence rate estimated including stratigraphic data is distinctly bimodal, with a second, lower peak in activity around 100 Ma. Volcanism then waned until the final vents were produced 10-90 Ma. Based on this model, volume flux is also bimodal, reached a peak rate of 1-8 km3 Myr-1 by 150 Ma and remained above half this rate until about 90 Ma, after which the volume flux diminished greatly. The onset of effusive volcanism from 200-150 Ma might be due to a transition of volcanic style away from explosive volcanism that emplaced tephra on the western flank of Arsia Mons, while the waning of volcanism after the 150 Ma peak might represent a larger-scale diminishing of volcanic activity at Arsia Mons related to the emplacement of flank apron lavas.

  10. Turbidite event history--Methods and implications for Holocene paleoseismicity of the Cascadia subduction zone (United States)

    Goldfinger, Chris; Nelson, C. Hans; Morey, Ann E.; Johnson, Joel E.; Patton, Jason R.; Karabanov, Eugene; Gutierrez-Pastor, Julia; Eriksson, Andrew T.; Gracia, Eulalia; Dunhill, Gita; Enkin, Randolph J.; Dallimore, Audrey; Vallier, Tracy; Kayen, Robert; Kayen, Robert


    Turbidite systems along the continental margin of Cascadia Basin from Vancouver Island, Canada, to Cape Mendocino, California, United States, have been investigated with swath bathymetry; newly collected and archive piston, gravity, kasten, and box cores; and accelerator mass spectrometry radiocarbon dates. The purpose of this study is to test the applicability of the Holocene turbidite record as a paleoseismic record for the Cascadia subduction zone. The Cascadia Basin is an ideal place to develop a turbidite paleoseismologic method and to record paleoearthquakes because (1) a single subduction-zone fault underlies the Cascadia submarine-canyon systems; (2) multiple tributary canyons and a variety of turbidite systems and sedimentary sources exist to use in tests of synchronous turbidite triggering; (3) the Cascadia trench is completely sediment filled, allowing channel systems to trend seaward across the abyssal plain, rather than merging in the trench; (4) the continental shelf is wide, favoring disconnection of Holocene river systems from their largely Pleistocene canyons; and (5) excellent stratigraphic datums, including the Mazama ash and distinguishable sedimentological and faunal changes near the Pleistocene-Holocene boundary, are present for correlating events and anchoring the temporal framework. Multiple tributaries to Cascadia Channel with 50- to 150-km spacing, and a wide variety of other turbidite systems with different sedimentary sources contain 13 post-Mazama-ash and 19 Holocene turbidites. Likely correlative sequences are found in Cascadia Channel, Juan de Fuca Channel off Washington, and Hydrate Ridge slope basin and Astoria Fan off northern and central Oregon. A probable correlative sequence of turbidites is also found in cores on Rogue Apron off southern Oregon. The Hydrate Ridge and Rogue Apron cores also include 12-22 interspersed thinner turbidite beds respectively. We use 14C dates, relative-dating tests at channel confluences, and

  11. Contrasting Permo - Carboniferous Evolution of Resita and Sirinia - Presacina Basins (South Carpathians, Romania); an overview. (United States)

    Tatu, M.; Seghedi, I.; Nutu, L. M.; Nicolae, I.


    rarely lens-like fresh water limestone. During the Permian in the Resita basin the volcanic activity was absent. In the Sirinia - Presacina basin the Lower Permian deposits are characterized by huge volcanic and volcano - sedimentary assemblages inter-fingering with red beds detritic formations. The Permian volcanism in the Sirinia - Presacina basin is dominant rhyolitic and started in subaqueous conditions. Early subaqueous domes (as isolated or as clusters) and lava flows led to the generation at their margins of huge volume of hyaloclastic breccias that turn unstable forming marginally turbiditic hyaloclastite aprons. In the Sirinia zone, where the magmas get to the shallower waters and/or to subaerial, the volcanic activity turned progressively to be explosive, generating phreatomagmatic eruptions. The result of this activity is up to several hundred meters of various deposits represented by pyroclastic flow (dominantly non-welded and welded ignimbrites), pyroclastic surge and fall out, all rich in accretionary lapilli. At the distal, marginal part of the volcanic environs the epiclastic, mostly lahar deposits are dominating, sometimes including layers of fallout deposits with accretionary lapilli that suggest their contemporaneous deposition. In the eastern part of Sirinia - Presacina basin (Cucuiova Hill) the presence of basalts as sills in the Permian sandstone deposits may be a sign of bimodal magmatic activity. As in the some of the Central Europe Permian basins the volcanic activity from Sirinia - Presacina basin is related to intra-basinal active faults and in particular with the intersection of fault systems having a pull-apart features (e.g. Stollhofen et al., 1999). The most important factor which was controlled the Permo - Carboniferous complex evolution of the Western and Central Europe was tectonic. The continue convergence between Laurasia and Gondwana during the Upper Carboniferous - Lower Permian (Ziegler, 1990) was generated a conjugate dextral

  12. Establishing aeolian particulate 'fingerprints' in an airport environment using magnetic measurements and SEM/EDAX (United States)

    Jones, Sue; Hoon, Stephen R.; Richardson, Nigel; Bennett, Michael


    The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of particulate matter (PM) from aviation activity on health and the environment. PM within the airport environment, in particular, may be derived from a wide range of potential sources including aircraft; vehicles; ground support equipment and buildings. In order to investigate and remediate potential problem sources, it is important to be able to identify characteristic particulate 'fingerprints' which would allow source attribution, particularly respirable particulates. To date the identification of such 'fingerprints' has remained elusive but remains a key research priority for the aviation industry (Webb et al, 2008). In previous PM studies, environmental magnetism has been used as a successful technique for discriminating between different emission types and particulate sources in both urban and industrial environments (e.g. Hunt et al 1984; Lecoanet et al 2003, Jones et al 2015). Environmental magnetism is a non-destructive and relatively rapid technique involving the use of non-directional, rock magnetic measurements to characterise the mineral magnetic properties of natural and anthropogenic materials. In other studies scanning electron microscopy (SEM) has also been used as an effective characterisation technique for the investigation of grain size and morphology of PM derived from vehicle emissions (e.g. Bucko et al 2010) and fossil fuel combustion sources (Kim et al 2009). In this study, environmental magnetic measurements and SEM/EDAX have been used to characterise dusts from specific aircraft sources including engines, brakes and tyres. Furthermore, these methods have also been applied to runway (both hard and grass covered surfaces), taxiway and apron dusts collected during extensive environmental sampling at Manchester International Airport, UK in order to

  13. Noctis Landing: A Proposed Landing Site/Exploration Zone for Human Missions to the Surface of Mars (United States)

    Lee, Pascal; Acedillo, Shannen; Braham, Stephen; Brown, Adrian; Elphic, Richard; Fong, Terry; Glass, Brian; Hoftun, Christopher; Johansen, Brage W.; Lorber, Kira; Mittlefehldt, David; Takagi, Yuta; Thomas, Peter; West, Michael; West, Stephen; Zolensky, Michael


    The proposed Noctis Landing Site/Exploration Zone (LS/EZ) is shown in Figure 1. Our preliminary study suggests that the proposed site meets all key Science and Resources (incl. Civil Engineering) requirements. The site is of significant interest, as the EZ not only offers a large number and wide range of regions of interest (ROIs) for short-term exploration, it is also located strategically at the crossroads between Tharsis and Valles Marineris, which are key for long-term exploration. The proposed site contains Regions of Interest (ROIs) that meet the following Science requirements: -­- Access to (1) deposits with a high preservation potential for evidence of past habitability and fossil biosignatures and (2) sites that are promising for present habitability. The site presents a wide variety of ROIs qith likely aqueous features and deposits, including sinous channels and valleys, slope gullies, lobate debris aprons, impact craters with lobate ejecta flows, and "bathtub ring" deposits. Neutron spectrometry also suggests hydrogen is present within the topmost 0.3 m or so of 4 to 10 wt% WEH (Water Equivalent Hydrogen). -­- Noachian and/or Hesperian rocks in a stratigraphic context that have a high likelihood of containing trapped atmospheric gases. Collapsed canyon rim material with preserved stratigraphy is abundantly present and accessible. -­- Exposures of at least two crustal units that have regional or global extents, that are suitable for radiometric dating, and that have relative ages that sample a significant range of martian geological time. Canyons floors in Ius Chasma, Tithonium Chasma, and plateau tops on Tharsis and in Sinai Planum offer access to distinct crustal units of regional extent. -­- Access to outcrops with linked morphological and/or geochemical signatures indicative of aqueous or groundwater/ mineral interactions. Iron and sulfur-bearing deposits on canyon floors in Noctis Labyrinthus, and in Ius Chasma (IC) and Tithonium Chasma (TC

  14. Design and Development of System Platform of “Study on Relationship between Natural Phenology and Climate Change” Based on WEB and GIS%基于WEB和GIS的“自然物候与气候变化关系的研究”系统平台的设计与开发

    Institute of Scientific and Technical Information of China (English)

    史彩霞; 李耀先; 李莉; 黄梅丽; 邓英姿


    [Objective] The research aimed to study design and development of system platform of "study on relationship between natural phenology and climate change" based on WEB and GIS. [ Method] Relied on the technologies of WEB and CIS, the system platform of "study on relationship between natural phenology and climate change" was developed based on the hybrid architecture of C/S (Client/Server) and B/S (Brower/Server). Moreover, its build process and functional module were detailedly introduced. [Result] The natural phenology and climate change in Guangxi were research objects of system platform of "study on relationship between natural phenology and climate change". By combining WEB and GIS with database, the primary application of research about relationship between natural phenology and climate change was realized. The system used hybrid architecture of C/S and B/S. The four layers of architecture were independent to improve security, stability and maintainability of system. The visual interface at the fore apron was simple, clear and easy to use. The generating program of GIS three-dimensional graph at the background was real-time and high-efficiency, providing powerful guarantee for stable and safe operation of phenology research work process. The system had functions of inquiry, analysis, statistical diagram, CIS three-dimensional graph and data export. Through the analysis of natural phenology observation data, the system could find variation rule of natural phenology as three-dimensional space (longitude, latitude and altitude) and its relationship with climate change. [ Conclusion ] The research laid good foundation for further deeply carrying out application of research about relationship between natural phenology and climate change. It also provided reference basis for recognizing nature and using change rule of phenology to execute production scheduling and strategic decision (seed-introdurtion and regionalization).%[目的]研究基于WEB和GIS的“自然

  15. Ground-water geology of the coastal zone, Long Beach-Santa Ana area, California (United States)

    Poland, J.F.; Piper, A.M.


    This paper is the first chapter of a comprehensive report on the ground-water features in the southern part of the coastal plain in Los Angeles and Orange Counties, Calif., with special reference to the effectiveness of the so-called coastal barrier--the Newport-Inglewood structural zone--in restraining landwar,-1 movement of saline water. The coastal plain in Los Angeles and Orange Counties, which covers some 775 square miles, sustains a large urban and rural population, diverse industries, and intensive agricultural developments. The aggregate ground-water withdrawal in 1945 was about 400,000 acre-feet a year, an average of about 360 million gallons a day. The dominant land-form elements are a central lowland plain with tongues extending to the coast, bordering highlands and foothills, and a succession of low hills and mesas aligned northwestward along the coastal edge of the central low- land plain. These low hills and mesas are the land-surface expression of geologic structure in the Newport-Inglewood zone. The highland areas that border the inland edge of the coastal plain are of moderate altitude and relief; most of the ridge crests range from 1,400 to 2,500 feet in altitude, but Santiago Peak in the Santa Ana Mountains attains a height of 5,680 feet above sea level. From these highlands the land surface descends across foothills and aggraded alluvial aprons to the central lowland, Downey Plain, here defined as the surface formed by alluvial aggradation during the post-Pleistocene time of rising base level. The Newport-Inglewood belt of hills and plains (mesas) has a maximum relief of some 500 feet but is widely underlain at a depth of about 30 feet by a surface of marine plantation. As initially formed in late Pleistocene time that surface was largely a featureless plain. Thus the present land-surface forms within the Newport-Inglewood belt measure the earth deformation that has occurred there since late Pleistocene time and so are pertinent with respect to

  16. The law of oil and gas distribution and mainly controlling factors of the passive rift basin:The Tanan depression of Tamuchage Basin%被动裂陷盆地油气分布规律及主控因素分析——以塔木察格盆地塔南坳陷为例

    Institute of Scientific and Technical Information of China (English)

    付晓飞; 王勇; 渠永红; 沙威


    -resevoir" ," three aspects compose the play" and "three types compoundly control the gas" are favour of forming the reservoir,so they are the typical reservoir model for the passive rift basin. The passive rift stage resut in the bottom wall of the antithetic fault low upward, the initiative rift stage result in the central anticlinal zone, and the reversion stage of the basin result in the reverse structure zone, and they provide place for two different hydrocarbon and secondary gas system to accumulate gas respectively. The onshore subsea apron accumulate gas in the central of depression, and formed the lithologic hydrocarbon reservoirs.%塔南凹陷为典型的被动裂陷盆地,构造演化历经了4个阶段:即被动裂陷阶段、主动裂陷阶段、断一坳转化阶段和坳陷阶段,形成两套含油气系统:即被动裂陷含油气系统和主动裂陷含油气系统,油气主要富集在被动裂陷含油气系统中.油气分布的主控因素概括为3个方面:1)是区域性盖层和长期发育的断层控制油气聚集的层位,盆地发育南一段上部和大一段两套泥质岩区域性盖层,厚度大,泥地比高,控制了两套含油气系统油气富集,长期发育的断层在盖层段形成剪切型泥岩涂抹,当SSF值大于5时,泥岩涂抹失去连续性,油气穿越区域性盖层垂向运移,在大二段聚集,形成次生油气藏.2)是有效烃灶和优质储层控制油气分布范围,主动裂陷阶段和被动裂陷阶段均发育一套烃源岩,被动裂陷阶段烃源岩为砂泥互层结构,排烃效率高,为优质烃源岩.大气水的淋滤作用和有机酸溶解作用分别在反向断层下盘和洼槽内部形成优质储层,油气短距离侧向运移,油气分布具有典型的“源控”和“优质储层控制”的特征.3)是反向断层、低隆起和扇体控制油气聚集,被动裂陷阶段构造沉降和翘倾作用形成大量反向断层,具有“三期同步造储”、“三面组合成藏”和“三类复合控

  17. 新疆某现代化肉牛屠宰加工过程中肠杆菌科细菌的检测研究%Detection of Enterobacteriaceae in a Beef Cattle Slaughtering and Processing Plant in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    堵舒桐; 彭斌; 王金泉; 张晓红; 马玉辉; 姚刚; 王志琴


    【目的】肠杆菌科细菌作为食品卫生指标菌较大肠菌群等指标菌更敏感,更准确,有着更重要的公共卫生学意义。检测新疆某现代化肉牛屠宰加工过程中肠杆菌科细菌,为有效对生产加工环节的风险关键点加以控制提供科学依据。【方法】参照 SN ∕T 0738—1997中的肠杆菌科细菌检测方法,对新疆某现代化屠宰厂屠宰﹑分割全过程中牛胴体表面及修整人员手﹑刀具﹑围裙,修整操作台及传输带等环节肠杆菌科细菌的污染状况进行检测分析。【结果】冲洗工序可使肠杆菌科细菌从1.64 log cfu∕cm2极显著降低到1.27 log cfu∕cm2(P ﹤0.01),经排酸后又极显著升高到2.46 log cfu∕cm2,分割肉表面的肠杆菌科细菌为3.55 log cfu∕cm2,极显著高于分割前(P ﹤0.01)。在分割环节中尤以修整工人的围裙和修整操作台污染较重。【结论】该肉牛屠宰加工企业存在一定的肠杆菌科细菌污染隐患,应将排酸环节,分割环节中修整工人围裙和修整操作台作为肠杆菌科细菌污染的主要风险关键点加以监控。%Objective] Enterobacteriaceae bacteria as an indicator for food hygienic situation are more sensitive and accurate than coliform bacteria,which have more important meaning for public health,therefore, through the detection of a modern beef slaughtering and processing process of Enterobacteriaceae bacteria,we can effectively control the key risk points during the whole processing procedures.[Method]In this study the enterobacteriaceae bacteria on beef carcass,splitting facilities and workers ′hands and aprons in a modern slaughterhouse in Xinjiang were detected according to the method stipulated in SN ∕T 0738 —1997.[Result]The result showed that after carcass washing process,the enterobacteriaceae bacteria were reduced significantly from 1.64 log cfu ∕cm2 to 1.27 log cfu ∕cm2 (P ﹤0.01).however,they were increased extremly to 2.46 log cfu

  18. An evolutionary scheme for morphological classification of Martian gullies (United States)

    Aston, A. H.; Balme, M.


    Martian gullies are geologically recent small-scale features characterised by an alcove-channel-apron morphology associated on Earth with liquid water. Since their discovery by Malin and Edgett (1), several theories have been advanced to explain their formation. These typically emphasise either groundwater processes (1, 2) or melting of ground ice or snowpack (3). The former approach has been challenged on the basis of gullies observed on hills and central peaks, where aquifers are unlikely (4). Studies of gullied walls have been undertaken (5), but though morphological classifications of gullies have been proposed (1), they are largely descriptive. This study proposes an evolutionary classification scheme and a pilot study to determine its potential to address controversies in gully formation. A morphological classification of gullies was developed, and four types identified: Type I: V-shaped gullies in slope mantling material or scree (i.e. not cutting bedrock); no distinct alcoves. Type II: Alcoves capped by a distinct and continuous stratum of rock. Type III: Alcoves extending vertically upslope, without reaching top of slope. Type IV: Alcoves reaching top of slope and cutting back into cliff. The types form an evolutionary sequence: in particular, the sequence II-III-IV appears to represent the development of many Martian gullies. Moreover, we have found that average length increases from Type I to Type IV. Furthermore, the presence of small gullies (mostly I and II) in the mantling deposits filling larger alcoves suggests multiple stages of gully activity. To test the classifications in practice, a sample of gullied slope sections imaged by MOC (Mars Orbital Camera) on Mars Global Surveyor at a resolution of 1-7 m/pixel were catalogued using ArcGIS software. 210 slope sections were covered, representing 1734 gullies across the southern mid-latitudes. Broad geographical coverage was obtained by working through MOC image numbers. For each slope section, the

  19. Effects of the earthquake of March 27, 1964, at Seward, Alaska: Chapter E in The Alaska earthquake, March 27, 1964: effects on communities (United States)

    Lemke, Richard W.


    area, where the rocks consist almost entirely of graywacke and phyllite, is from near north to N. 20° E. Beds and cleavage of the rocks commonly dip 70° W. or NW. to near vertical. Locally, the rocks are complexly folded or contorted. So major faults were found in the mapped area, but small faults, shear zones, and joints are common. Surficial deposits of the area hare been divided for mapping into the following units: drift deposits, alluvial fan deposits, valley alluvium, intertidal deposits, landslide deposits, and artificial fill. Most of these units intergrade and were deposited more or less contemporaneously. The drift deposits consist chiefly of till that forms moraines along the lower flanks of the Resurrection River valley and up tributary valleys. The till is predominantly silt and sand and lesser amounts of clay-size particles, gravel, cobbles, and boulders. Glacial outwash and stratified ice-contact deposits constitute the remainder of the drift deposits. Fans and fan-deltas have been deposited at the valley mouths of tributary streams. Some, including the one upon which Seward built, project into Resurrection Bay, and deltaic-type deposits form their distal edges. The larger fans—composed chiefly of loosely compacted and poorly sorted silt, sand, and gravel—form broad aprons having low gradients. The fan deposits range in thickness from about 100 feet to possibly several hundred feet and, at least in some places, lie on a platform of compact drift. Smaller fans at the mouths of several canyons have steep gradients and considerable local relief. Valley alluvium, deposited chiefly by the Resurrection River, consists mostly of coarse sand and fine to medium gravel. In the axial part of the valley it is probably more than 100 feet thick. Near the head of Resurrection Bay, the alluvium is underlain by at least 75 feet of marine deltaic sediments, which are in turn underlain by 600 or more feet of drift in the deepest part of the bedrock valley. Beach

  20. The origin of the Dargom canal in the oasis of Samarkand (Uzbekistan). A new scenario from geoarcheological data (United States)

    Marconi, V.; Mantellini, S.; Picotti, V.; Gabbianelli, G.; Tosi, M.


    As the main oases developed in the arid regions of Central Asia, the region of Samarkand is the outcome of large hydraulic works carried out since the past times. The main result of such a great landscape transformation is a complex irrigation network formed by several artificial channels and useful for both urban water supply and irrigation purposes. Within the framework of the Italo-Uzbek Archaeological Project begun in 2001, a specific study was aimed to reconstruct the history of Dargom, the primary canal on the South of the city, and its relationships with the settlement dynamics. According to the most accepted theories, the Dargom was dug during the Achaemenid Age (6th-4th c. BC) as a consequence of a master plan linked to a strong central political power. The new investigations carried out by a joined team of Archaelogists and Geologists from the University Bologna allowed a new hypothesis on the way of digging and the chronology of the Dargom itself. The analyses on the historical settlement patterns seem to suggest a low development of Samarkand's territory during the Achaemenid times, whilst the increasing of sites during the Early Middle Age (5th-8th c.) can be explained throughout the rich trades along the Silk Road as well as the development of irrigated agriculture. The present-day Dargom is a high sinuosity channel deeply incised into the bedrock flowing to the east, strongly resembling a natural channel. It has been excavated for around 70 km along an apron of alluvial fans sourced by a southern mountain range. Its morphology clearly document a natural evolution after excavation: incision and meandering took place, likely due to the increasing gradient related to the headward migration of lowering of the base-level and the decrease of the bed load through time. Field survey around the fortress of Kafir Kala, the main archeological site geographically linked to the Dargom, allowed reconstructing the original bed of the canal, marked by a layer of

  1. Geologic framework, age, and lithologic characteristics of the North Park Formation in North Park, north-central Colorado (United States)

    Shroba, Ralph R.


    Deposits of the North Park Formation of late Oligocene and Miocene age are locally exposed at small, widely spaced outcrops along the margins of the roughly northwest-trending North Park syncline in the southern part of North Park, a large intermontane topographic basin in Jackson County in north-central Colorado. These outcrops suggest that rocks and sediments of the North Park Formation consist chiefly of poorly consolidated sand, weakly cemented sandstone, and pebbly sandstone; subordinate amounts of pebble conglomerate; minor amounts of cobbly pebble gravel, siltstone, and sandy limestone; and rare beds of cobble conglomerate and altered tuff. These deposits partly filled North Park as well as a few small nearby valleys and half grabens. In North Park, deposits of the North Park Formation probably once formed a broad and relatively thick sedimentary apron composed chiefly of alluvial slope deposits (mostly sheetwash and stream-channel alluvium) that extended, over a distance of at least 150 kilometers (km), northwestward from the Never Summer Mountains and northward from the Rabbit Ears Range across North Park and extended farther northwestward into the valley of the North Platte River slightly north of the Colorado-Wyoming border. The maximum preserved thickness of the formation in North Park is about 550 meters near the southeastern end of the North Park syncline.The deposition of the North Park Formation was coeval in part with local volcanism, extensional faulting, development of half grabens, and deposition of the Browns Park Formation and Troublesome Formation and was accompanied by post-Laramide regional epeirogenic uplift. Regional deposition of extensive eolian sand sheets and loess deposits, coeval with the deposition of the North Park Formation, suggests that semiarid climatic conditions prevailed during the deposition of the North Park Formation during the late Oligocene and Miocene.The North Park Formation locally contains a 28.1-mega-annum (Ma

  2. 早期食管癌及癌前病变多环黏膜切除60例报告%Multi-band Mucosectomy for Early-stage Esophageal Carcinoma and Precancerous Lesions:Report of 60 Cases

    Institute of Scientific and Technical Information of China (English)

    黄涛; 张红; 杨国栋; 冯迎春; 凌颖; 蒋玲; 冯志松


    mucosa was sucked into the cap , a rubber band was released , pseudopolyps were removed with the hexagonal snare , and tissue samples were collected .The above mentioned procedures were repeated until the complete removal of the lesion. Results There were a total of 84 lesions in the 60 cases.Except a conversion to thoracic surgery was conducted in 1 case because of bleeding , the remaining 83 lesions in 59 cases (98.3%) were successfully removed at one-time.The operation used a total of 289 hair aprons, with 1-12 rounds in each case (mean, 4.8 rounds/case).The operation time was 10-60 minutes (mean, 23.5 minutes).The resection was 1.0-10 cm in length and <3/4 esophageal circumference in width .Intraoperative massive hemorrhage occurred in 3 cases (5.0%), 2 of which were given intraoperative hemostasis and 1 of which underwent conversion to open surgery . No postoperative hemorrhage happened .Intraoperative perforation was found in 1 case (1.7%), which was cured by using all-covered metal stent implantation for conservative treatment .Postoperative pathological outcomes showed no residual cancer in basal part in all specimens , and 9 cases of carcinoma in situ , 29 cases of high-grade neoplasia , 12 cases of low-grade neoplasia , 6 cases of parakeratosis , 1 case of granular cell tumor , and 3 cases of polyp/inflammatory hyperplasia .Follow-up examinations in 59 cases for 1-23 months showed 2 cases (3.4%) of esophageal stenosis, which were relieved after bougienage .No local recurrence or lymph node metastases was found . Conclusion MBM treatment for early-stage esophageal cancer and precancerous lesions is safe , effective, and reliable, being worthy of wide promotion .

  3. Effects of the earthquake of March 27, 1964, at Seward, Alaska: Chapter E in The Alaska earthquake, March 27, 1964: effects on communities (United States)

    Lemke, Richard W.


    area, where the rocks consist almost entirely of graywacke and phyllite, is from near north to N. 20° E. Beds and cleavage of the rocks commonly dip 70° W. or NW. to near vertical. Locally, the rocks are complexly folded or contorted. So major faults were found in the mapped area, but small faults, shear zones, and joints are common. Surficial deposits of the area hare been divided for mapping into the following units: drift deposits, alluvial fan deposits, valley alluvium, intertidal deposits, landslide deposits, and artificial fill. Most of these units intergrade and were deposited more or less contemporaneously. The drift deposits consist chiefly of till that forms moraines along the lower flanks of the Resurrection River valley and up tributary valleys. The till is predominantly silt and sand and lesser amounts of clay-size particles, gravel, cobbles, and boulders. Glacial outwash and stratified ice-contact deposits constitute the remainder of the drift deposits. Fans and fan-deltas have been deposited at the valley mouths of tributary streams. Some, including the one upon which Seward built, project into Resurrection Bay, and deltaic-type deposits form their distal edges. The larger fans—composed chiefly of loosely compacted and poorly sorted silt, sand, and gravel—form broad aprons having low gradients. The fan deposits range in thickness from about 100 feet to possibly several hundred feet and, at least in some places, lie on a platform of compact drift. Smaller fans at the mouths of several canyons have steep gradients and considerable local relief. Valley alluvium, deposited chiefly by the Resurrection River, consists mostly of coarse sand and fine to medium gravel. In the axial part of the valley it is probably more than 100 feet thick. Near the head of Resurrection Bay, the alluvium is underlain by at least 75 feet of marine deltaic sediments, which are in turn underlain by 600 or more feet of drift in the deepest part of the bedrock valley. Beach

  4. Research on the Distribution and Characteristics of Moso Ethnic Costume during the Ming and Qing Dynasties

    Institute of Scientific and Technical Information of China (English)

    YANG Linjun


    Chinese .The women's costume , while keeping the traditional hair style and sheep skin leather cape , experienced some changes in accordance with Han and Mongo-lian costume . Therefore , the women started to wear long gowns, trousers, pleated aprons, and the very typical “seven -star cape”. In the Yongning -Yanyuan area , the traditional Moso costume, such as the long skirt , was kept, but some characteristics of Tibetan costume were also absorbed .In the areas from Beidi of Shangri -la to Eya of Muli, the characteristics of costume in the Ming dynasty were completely preserved , and only a few Tibetan costume elements were absorbed dur-ing the later period of the Qing dynasty .   Through an analysis of the geographical distri-bution and characteristics of the Moso costumes in the Ming and Qing dynasties , we can notice that the Moso costume had developed from a relatively fuzzy “far vision” to a relatively clear “close vi-sion”, and had formed three different costume cul-ture zones , which constituted the present day mul-tiple cultural pattern of the Moso ethnic costume . Seen from the perspective of the three costume zones, the characteristics of the traditional ethnic costume had been kept .However , its appearance and cultural connotations manifested very obvious changes.So, what were the factors promoting such profound change? And what caused the formation of the three different ethnic costume zones? There were many causes for the change in ethnic cos-tume , including internal and external ones .Among them, the internal causes were the key factor .The appearance of differences between the Moso ethnic costumes during the Ming and Qing dynasties were due to the following three reason   Firstly, it was closely related to the policy of the central court .In the areas, such as Lijiang , which were directly managed by the officials sent by the central government after implementation of the gaituguiliu policy ( replacement of native offi-cials with

  5. Channel geometry and discharge estimates for Dao and Niger Valles, Mars (United States)

    Musiol, S.; van Gasselt, S.; Neukum, G.


    parallel to the channel margins are considered to be the result of extensional deformation. Two smoothfloored collapse depressions, representing source areas, cut into the flanks of Hadriaca Patera (Ausonia and Peraea Cavus) and are connected to Dao Vallis by a region of irregular valley floor materials. These regions are all bounded by steep scarps and are interpreted to be collapse depressions in water- or ice-rich materials. Linear and curvilinear features that are approximately parallel to the channel walls are seen in some parts of the channel floors. The channel walls show typical spur-and-gully morphology. It has been suggested that gullies can be exposed by a removal of semi-competent mantling deposits along the walls of Dao Vallis. The walls could either be a source of volatiles or provide an insulating layer [6]. A possible sedimentary deposit is observed on the floor of Hellas near the terminus of Dao Vallis [1]. Geologic evolution of the eastern rim of Hellas The oldest geologic materials result from the basin-forming impact and consist of the Noachian basin rim unit and mountainous materials. Volcanism began in the late Noachian or Early Hesperian epoch with the formation of the highland paterae. The low shields of Hadriaca and Tyrrhena Patera are interpreted to be composed primarily of pyroclastic flows. The distribution of flank materials at Hadriaca Patera can be attributed to the emplacement of gravity-driven pyroclastic flow, which is in contrast to the caldera-filling material and implies a transition from explosive to effusive volcanism at the highland paterae [5]. Substantial modification of the cratered highlands characterizes the Hesperian Period, with the formation of the smooth plateau materials, predominantly sedimentary plains-infilling low-lying intermontane areas. Continuation of this style of erosion extended into the Amazonian Period with the emplacement of debris aprons. The channels on the flanks of Hadriaca Patera are clearly truncated by

  6. Geology and ground-water resources of the island of Kauai, Hawaii (United States)

    Macdonald, Gordon A.; Davis, Dan A.; Cox, Doak C.


    the Koloa volcanic series. The explosions that built the tuff cone at Kilauea Bay threw up fragments of limestone from a buried reef. Much of the apron of lavas of the Kalna series around the northeastern side of the island probably rests on a platform formed below present sea level by wave erosion and the growth of coral reef.As the sea rose around the island, the valley mouths were alluviated. Several levels of the sea higher than the present one probably are represented. Some stream terraces may be graded to a stand of the sea as high as 260 feet above present sea level, but no positive evidence for stands higher than 25 feet have been found. Well-preserved shorelines are recognized approximately 25 and 5 feet above sea level. Much of the present coral reef appears to have been formed when the sea stood about 5 feet higher than now, and reduced to its present level by solutional weathering and wave erosion.The lavas of the Napali formation of the Waimea Canyon volcanic series are highly permeable. They carry basal water over much of the island, and yield it freely to wells. This water is fresh everywhere except very close to the coast on the leeward side of the island. In some areas they may contain water confined at high levels between dikes. The lavas of the Olokele and Haupu formations are moderately to poorly permeable. They probably contain fresh water at sea level, but would not yield it readily to wells. Locally, ash beds perch small bodies of fresh water at high levels in the lavas of the Olokele formation, but these are of no economic importance. The lavas of the Makaweli formation also arc moderately to poorly permeable. They carry fresh or brackish water at sea level. In general, they yield water to wells less readily than the lavas of the Napali formation, but more readily than the lavas of the Olokele. The conglomerates and breccias of the Mokuone member are poorly permeable, but are not known to perch more than a slight amount of water in the

  7. Lakshmi Planum, Venus: Assessment of models using observations from geological mapping (United States)

    Ivanov, M. A.; Head, J. W.


    suggest more extensive presence under younger plains units, forming basement. Densely fractured plains (pdl) appear younger than tessera; the largest massifs of pdl occur in Atropos and Itzpapalotl where plains are further deformed by broad ridges and to some degree resemble the tessera deformation patterns. The ridges are generally conformal to the strike of Akna/Freyja Montes, occur within large areas of pdl adjacent to the mountain ranges, and clearly relate to the orogenic phase of formation of mountain belts [10,16-19,11,20- 23,25,26,29]. Shield plains and regional plains embay mountainous ridges both outside and inside Lakshmi Planum, which implies that the orogenic phase was toward earlier stages of the observable geological history. Shield plains were emplaced after the main phase of mountain belt formation and before regional plains, but exclusively outside of the plateau. The lower unit of regional plains (rp1) postdates shield plains; occurrences are concentrated S of Lakshmi Planum and in the interior of Lakshmi. The thickness of unit rp1 is small because outliers of older units occur within the broad regional plains. Youngest units, smooth/lobate plains, are superposed on regional plains and undeformed by tectonic structures; they were emplaced after cessation of major tectonic activity. Smooth/lobate plains form extensive lava aprons around Colette and Sacajawea Paterae, representing the latest volcanic activity inside Lakshmi Planum. Testing models of Lakshmi Planum formation: Detailed geological analysis thus allows definition of map units, establishing the sequence of major events during formation of Lakshmi, and testing the suite of models proposed to explain the mechanisms of formation of this structure. The interpreted nature of units and the sequence of events strongly contradict the predictions of divergent models: 1) The very likely presence of an ancient (craton-like) tessera massif in the core of Lakshmi; such a core is inconsistent with the rise