Anatomy of the minor fissure: assessment with high-resolution CT and classification

International Nuclear Information System (INIS)

Ariyuerek, Macit O.; Yelgec, Selcuk N.; Guelsuen, Meltem; Karabulut, Nevzat

2002-01-01

The aims of this study were to investigate the anatomy of the minor fissure and its variations on high-resolution CT (HRCT) sections and to propose a detailed classification. The prospective study included 67 patients who were referred to CT for various indications. High-resolution CT examinations (1.5-mm collimation) were obtained through the region of the minor fissure. The CT scans were assessed for the presence, completeness, and configuration of the minor fissure. Various configurations of the minor fissure were classified into four major types, based on whether the highest portion of the middle lobe upper surface was medial (type I), lateral (type II), posterior (type III), or central (type IV). Minor fissure was identified in 65 (97%) of 67 patients, and absent in 2 (3%) cases. The fissure was incomplete in 35 (54%) of 65 patients. Type-I minor fissure is seen in 28 (43%) patients, type II in 22 (34%), type III in 5 (8%), and type IV in 2 (3%) patients. Because the majority of the fissure was absent in 8 (12%) of 35 patients with incomplete fissure, they were considered indeterminate. Comprehensive knowledge of the various configurations of the minor fissure is helpful in correct localization of a lesion and its extension. In equivocal cases, limited thin-section CT scans through the fissure delineate the anatomy more clearly and provide greater degree of precision in localizing pulmonary lesions. (orig.)

Intracranial lipoma in the sylvian fissure

International Nuclear Information System (INIS)

Ogasawara, Kuniaki; Kinjo, Toshihiko; Onuma, Takehide

1988-01-01

An experience with an operation on a case of intracranial lipoma in the sylvian fissure is reported. A 14-year-old man had complained of attacks of abnormal behavior for 2 years and was diagnosed by a psychiatrist as suffering from temporal epilepsy. A computed tomography (CT) scan indicated an abnormal shadow on the brain, and so he was admitted to our hospital. On admission, the results of physical and neurological examinations were normal. An electroencephalogram recorded irregular δ waves and sharp waves over the right frontotemporal region, however. A CT scan showed a round-shaped, extremely low-density area, with calcification of the wall and without contrast-enhancement, in the left sylvian fissure. No abnormal finding was seen in plain skull X-P or in left-carotid angiography. Left-frontotemporal craniotomy was performed to remove the tumor. A solid yellowish tumor was found in the sylvian fissure and totally removed. Histologically, it proved to be a lipoma. The postoperative course was uneventful, and the patient was discharged without any neurological deficit. We discussed the neuroradiological findings of sylvian lipomas. As far as we have learned in an extensive review of the literature, there have been nine reports on intracranial lipomas in the sylvian fissure; as for sylvian lipomas which were detected on a CT scan during life, there have been only six cases other than the present one. (author)

Interlobar fissures involvement by lung cancer. Evaluation with thin-section computed tomography images

International Nuclear Information System (INIS)

Kato, Yuji; Yamada, Kouzo; Nomura, Ikuo; Noda, Kazumasa; Ishiwa, Naoki; Maehara, Takamitsu; Kameda, Youichi

1998-01-01

Pleural involvement of interlobar fissure by a tumor is one of the most important factors in the clinical diagnosis of lung cancer. A positive finding of incomplete interlobar fissure of the lung influences not only the surgical procedure but also the prognosis. The aim of this retrospective study was to investigate the usefulness of thin-section computed tomography (CT) compared with conventional CT in the detection of pleural invasion of the interlobar fissure by lung cancer or incomplete interlobar fissure, and the results of surgery, according to the involvement of the pleural surface. We reviewed 90 patients whose tumors were adjacent to the interlobar fissure of the lung through conventional CT scans and subsequent thoracotomy. A comparison of diagnoses based on the findings of thin-section CT and pathologic examination showed that thin-section CT was 94% accurate for pleural invasion of the interlobar fissure, and 100% for incomplete interlobar fissure. Conventional CT, however, was only 63% accurate for pleural invasion of the interlobar fissure and 31% for incomplete interlobar fissure. This leads us to conclude that thin-section CT is helpful in the accurate evaluation of pleural invasion of the interlobar fissure and in the findings of incomplete interlobar fissure in lung cancer for patients in whom tumors are adjacent to the interlobar fissure on conventional CT findings. (author)

Horizontal fissure on neonatal plain chest radiographs: clinical implications

International Nuclear Information System (INIS)

Konarzewska, J.; Zawadzka-Kepczynska, A.; Bianek-Bodzak, A.; Kawinska-Kilianczyk, A.; Domzalska-Popadiuk, I.

2005-01-01

Regardless of etiology, pleural fluid, even in small amounts, can be visualized on the neonatal chest x-ray picture within pulmonary fissures. It remains unclear whether a marked horizontal fissure unaccompanied by any other radiological symptoms is of diagnostic value or not. Ninety-one consecutive neonatal chest radiographs with marked horizontal fissure were retrospectively analyzed. The images were made between 1999 and 2005 on 69 newborns admitted to the Neonatology Department, Institute of Obstetrics and Gynecology, Medical University of Gdansk. Analysis of the radiographs was conducted independently by three radiologists based on the following criteria: fissure thickness (marked or thickened), bronchovascular markings (increased or normal), size and shape of the heart (normal or abnormal), presence or absence of pulmonary infiltration, atelectasis, and changes related to wet lung syndrome. Due to divergent interpretations, the ultimate interpretation was established by consensus in 25 cases. The radiological findings were compared with clinical data. The compatibility of the three independent interpreters was statistically significant (p<0.0001). Marked transverse fissure was the only radiological finding on 66 x-rays. In 63 cases (69.2%) the children were asymptomatic as well. In 3 cases (3.3%) clinical symptoms of respiratory tract infection occurred. On the other 25 images, horizontal fissure was accompanied by other radiological symptoms. Chest x-ray results corresponded with clinical symptoms in 24 cases (26.4%). One child (1.1%) with radiological evidence of wet lung syndrome did not present any typical clinical symptoms of it. Horizontal fissure noted on a neonatal chest x-ray seems to be of minor diagnostic value if not accompanied by any other radiological symptoms. (author)

Cell Behaviors during Closure of the Choroid Fissure in the Developing Eye

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Gaia Gestri

2018-02-01

Full Text Available Coloboma is a defect in the morphogenesis of the eye that is a consequence of failure of choroid fissure fusion. It is among the most common congenital defects in humans and can significantly impact vision. However, very little is known about the cellular mechanisms that regulate choroid fissure closure. Using high-resolution confocal imaging of the zebrafish optic cup, we find that apico-basal polarity is re-modeled in cells lining the fissure in proximal to distal and inner to outer gradients during fusion. This process is accompanied by cell proliferation, displacement of vasculature, and contact between cells lining the choroid fissure and periocular mesenchyme (POM. To investigate the role of POM cells in closure of the fissure, we transplanted optic vesicles onto the yolk, allowing them to develop in a situation where they are depleted of POM. The choroid fissure forms normally in ectopic eyes but fusion fails in this condition, despite timely apposition of the nasal and temporal lips of the retina. This study resolves some of the cell behaviors underlying choroid fissure fusion and supports a role for POM in choroid fissure fusion.

Research of compression strength of fissured rock mass

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А. Г. Протосеня

2017-03-01

Full Text Available The article examines a method of forecasting strength properties and their scale effect in fissured rock mass using computational modelling with final elements method in ABAQUS software. It shows advantages of this approach for solving tasks of determining mechanical properties of fissured rock mass, main stages of creating computational geomechanic model of rock mass and conducting a numerical experiment. The article presents connections between deformation during loading of numerical model, inclination angle of main fracture system from uniaxial and biaxial compression strength value, size of the sample of fissured rock mass and biaxial compression strength value under conditions of apatite-nepheline rock deposit at Plateau Rasvumchorr OAO «Apatit» in Kirovsky region of Murmanskaya oblast. We have conducted computational modelling of rock mass blocks testing in discontinuities based on real experiment using non-linear shear strength criterion of Barton – Bandis and compared results of computational experiments with data from field studies and laboratory tests. The calculation results have a high-quality match to laboratory results when testing fissured rock mass samples.

Fissure fillings from Gideaa, central Sweden

International Nuclear Information System (INIS)

Tullborg, E.L.; Larsson, S.Aa.

1983-08-01

The most frequent fissure filling minerals at Gideaa are calcite, chlorite, pyrite, laumontite, stilbite, smectite, quartz and epidote. Potentially young minerals, i.e. minerals which can be formed during present conditions, are smectite, calcite and quartz, Equilibrium calculations show that these minerals can be stable in the water analysed from Gideaa. In borehole Gi 2, the water exhibits a greater equilibrium with existing minerals in the fissures than water from Gi 4. This is due to the recharge of the water in Gi 4 and discharge of the water in Gi 2. When carbonate saturated water penetrated through the bedrock, calcite precipitated within the more superficial portions of the rock. However, both calcite and zeolite fissures fillings are associated with certain zones in the drill holes. A large number of fractures can be concluded to be of post-Jotnian age. Stilbite, calcite and smectite are associated with these fractures. Laumontite can also be assumed to belong here. The dolerites in the area exhibit a high fracture frequency but a relatively low hydraulic conductivity. This is due to the fact that smectite is very prevalent in the dolerite fractures, Several generations of fracturefilling minerals (above all calcite) have been found in a single fracture. Stable isotope analyses of fissure filling calcites indicate that there are three different groups of calcite. Most of the calcites could not have been precipitated from water of present-day isotope composition at Gideaa, whereas recent calcite may be found in one of the groups. Another group of calcite was precipitated during hydro-thermal conditions.(author)

Experimental study of strontium sorption on fissure filling material

Energy Technology Data Exchange (ETDEWEB)

Eriksen, T E; Cui, Daqing [Royal Institute of Technology, Stockholm (Sweden). Dept. of Chemistry

1994-12-01

We have carried out a comparative study of sorption and desorption of strontium in groundwater on separated magnetic and size fractions of fissure filling material taken from natural fissures in granitic rock. Complete reversibility of the sorption process was demonstrated by identical Freundlich isotherms, isotopic exchangeability and pH dependence of the distribution coefficients Rd. The sorption was found to be strongly pH dependent in the range 3-11. The pH effect can be accommodated in the sorption model by considering the surface areas and surface charges of the minerals in the fissure filling material. 20 refs, 9 figs, 3 tabs.

Experimental study of strontium sorption on fissure filling material

International Nuclear Information System (INIS)

Eriksen, T.E.; Cui, Daqing

1994-12-01

We have carried out a comparative study of sorption and desorption of strontium in groundwater on separated magnetic and size fractions of fissure filling material taken from natural fissures in granitic rock. Complete reversibility of the sorption process was demonstrated by identical Freundlich isotherms, isotopic exchangeability and pH dependence of the distribution coefficients Rd. The sorption was found to be strongly pH dependent in the range 3-11. The pH effect can be accommodated in the sorption model by considering the surface areas and surface charges of the minerals in the fissure filling material. 20 refs, 9 figs, 3 tabs

New diagnostic technology and hidden pits and fissures caries

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Fabrizio Guerra

2015-10-01

Full Text Available The accuracy in pits and fissures caries detection is of paramount importance in dental caries primary and secondary prevention. A combination of visual examination and probing is currently the mainstay of occlusal caries diagnosis. Unfortunately, these types of inspection alone may leave a certain number of pit and fissure caries undetected. The Vista Cam iX fluorescence camera (Durr Dental, Bietigheim-Bissingen, Germany is a novel dental diagnostic tool for quantitative assessment of dental caries with high specificity for carious lesions detection. In the presented cases photographic images, representing the visual diagnostic approach, are applied as integration to VistaCam iX Proof images. A step-by-step sequence of inspection and assessment of operative treatment need is presented in a case of hidden pit and fissure caries on a permanent molar. Based on the reported case, it could be observed that VistaCam iX Proof shows promising results in hidden pits and fissures caries detection and could be considered a non-invasive examination method that facilitate the detection of early lesions and a potential diagnostic aid.

Diagnostic problems in the identification of fissures (incomplete fractures) in horses

International Nuclear Information System (INIS)

Huskamp, B.; Stadtbaeumer, G.; Mengeler, U.; Nowak, M.

1994-01-01

Diagnosing bone-fissures as part of examinations of lameness often confronts the examining veterinarian with problems, which can end on being forensic matters. A fissure which is an incomplete fracture, whereby the division of the continuity ends in healthy bone tissue may in some cases initially not be shown radiologically. Initially strong superior-lameness combined with part sensitivity of pressure are apparent in the area of the line of fissure without soft-tissue swelling. Depending on the localisation of the fracture minor lameness can be apparent. If a fissure has initially been diagnosed, it is necessary to examine the affected limb radiologically from at least two projections appealing the corresponding date for exposure. If the initial diagnosis can not be confirmed radiologically, diagnostic anaesthesia is permitted in exceptional cases. If there is any doubt about the result, the affected limb must be held at rest until the possibility of a fissure can be excluded. The owner of the horse must be informed about problems of diagnostics and their risks [de

The Use of Pit and Fissure Sealants—A Literature Review

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Reem Naaman

2017-12-01

Full Text Available This paper reviews the literature and discusses the latest updates on the use of pit and fissure sealants. It demonstrates the effectiveness of pit and fissure sealants in preventing caries and the management of early carious lesions. It compares the use of different sealant materials and their indications. It describes the application technique for sealants. It also reviews the cost-effectiveness of sealants as a preventive strategy. From this review and after the discussion of recently published studies on pit and fissure sealants, it is evident that sealants are effective in caries prevention and in preventing the progression of incipient lesions. It is therefore recommended that pit and fissure sealant be applied to high-caries-risk children for optimum cost-effectiveness. It is a highly sensitive technique that needs optimum isolation, cleaning of the tooth surface, etching, and the application of a thin bonding layer for maximum benefit. Recall and repair, when needed, are important to maximize the effectiveness of such sealant use.

The Use of Pit and Fissure Sealants—A Literature Review

Science.gov (United States)

Naaman, Reem; El-Housseiny, Azza A.; Alamoudi, Najlaa

2017-01-01

This paper reviews the literature and discusses the latest updates on the use of pit and fissure sealants. It demonstrates the effectiveness of pit and fissure sealants in preventing caries and the management of early carious lesions. It compares the use of different sealant materials and their indications. It describes the application technique for sealants. It also reviews the cost-effectiveness of sealants as a preventive strategy. From this review and after the discussion of recently published studies on pit and fissure sealants, it is evident that sealants are effective in caries prevention and in preventing the progression of incipient lesions. It is therefore recommended that pit and fissure sealant be applied to high-caries-risk children for optimum cost-effectiveness. It is a highly sensitive technique that needs optimum isolation, cleaning of the tooth surface, etching, and the application of a thin bonding layer for maximum benefit. Recall and repair, when needed, are important to maximize the effectiveness of such sealant use. PMID:29563440

Preferential flow in fissured sediments in desert soils related to radioactive waste disposal

International Nuclear Information System (INIS)

Scanlon, B.R.; Raney, J.A.

1992-01-01

Unsaturated flow in fissured sediments in the Chihuahuan Desert of Texas was examined to determine if these features act as preferred pathways for water and solute transport. Fissures are surface features, or gulleys, that are underlain by fractures filled with sediment derived from surrounding areas. Hydraulic and chemical approaches were used to investigate unsaturated flow processes beneath and adjacent to fissures, and the results were compared with data from surrounding geomorphic systems such as arroyos, ephemeral streams, and interstreams. Typically, high water potentials in surficial sediments result from infiltration of recent precipitation. Below this surficial zone of high water potentials lies a zone of low water potentials that is much thinner beneath the fissure than in adjacent sediments or in sediments beneath ephemeral streams and interstreams. Maximum chloride concentrations in profiles in the near-surface fissured sediments were much lower than those measured in all other geomorphic systems. The corresponding moisture velocities in the fissured sediments ranged from 10 to 70 mm/yr. A tracer experiment demonstrated higher downward water and solute transport in the fracture fill beneath the fissure relative to adjacent sediments. Numerical simulations of the tracer experiment with the computer code TRACR3D reproduced the overall shape of the tracer plume. Sensitivity analyses demonstrated that the tracer plume is most sensitive to spatial variability in soil texture and the corresponding hydraulic parameters. The results from this study suggest that sediments in the fissured area act as preferred pathways in the shallow subsurface because surface runoff is concentrated in the fissures and because underlying fractures and cavities provide avenues for moisture and solute transport

Recent Advances in the Pharmacotherapy of Chronic Anal Fissure: An Update

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Bikash Medhi

2008-07-01

Full Text Available Surgical sphincterotomy reduces anal tone and sphincter spasm and promotes ulcer healing. Because the surgery is associated with the side effect of faecal incontinence, pharmacological agents to treat chronic anal fissure have been explored recently. Glyceryl trinitrate (GTN ointment (0.2% has an efficacy of up to 68% in healing chronic anal fissure, but it is associated with headache as the major and most common side effect. Though botulinum toxin injected into the anal sphincter healed over 80% of chronic anal fis-sures, it is more invasive and expensive than GTN therapy. Diltiazem ointment achieved healing of chronic anal fissure comparable to 0.2% GTN ointment but was associated with fewer side effects. Other drugs that have been tried are lidocaine, the alpha-adrenergic antagonist indoramin, and the potassium channel opener minoxidil.

Penetration of fluoride-containing self-gelling liquids into human molar occlusal fissures in vitro.

Science.gov (United States)

Bottenberg, P; Slop, D; Coomans, D

1989-01-01

In this in vitro study the ability and speed of self-gelling liquid compositions to penetrate into fissures were evaluated. Two formulations containing either tetraethylsilicate, ammonium fluoride, and sodium lauryl sulfate or tetraethylsilicate, sodium fluoride, and cetylpyridinium chloride at different concentrations were used. It is shown that fissure penetration occurs when a certain minimum content of surface-active agent is present. Fissure penetration is achieved within 3-4 s, according to the fissure morphology.

PERBEDAAN TOPICAL FLUORIDE APPLICATION DAN FISSURE SEALANT DALAM MENCEGAH KARIES PADAGIGI MOLAR SATU

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Pawarti Pawarti

2017-07-01

Full Text Available Abstract: Topical Fluoride Application And Fissure Sealant To Prevent Dental Caries Permanent First Molars. Anatomy pits and fissures of teeth are caries initiation vulnerable areas of the permanent molars that grow at the age of 6 years where children can not perform oral hygiene. Caries prevention can be done by closing the pits and fissures or application of fluoride (topical fluoride application on the surface of the teeth. The purpose of this study was to analyze the difference fissure sealants and topical application of fluoride to prevent dental caries of first permanent molars. This study was a quasi-experimental study with time series, a sample was taken by purposive 117-second grade students of SDN District of North Pontianak. Data were analyzed using t-test. The result showed that fissure sealant more effective in caries prevention of first permanent molar than topical fluoride application where there were none caries teeth after and month fissure sealant, 25% sealant partially off and 11% fully off. Teeth that have done fluoride after 6 months of 3.9% of dental caries, the eighth month of 5.4% of dental caries. There was a significant difference between the effectiveness of fissure sealants with topical application of fluoride to prevent dental caries in first permanent molars p-value < 0.05, after 6-month p-value: 0.004 and after 8-month p-value: 0.001. Abstrak: Topical Fluoride Application Dan Fissure Sealant Untuk Mencegah Karies Pada Gigi Molar Satu Permanen. Anatomi pit dan fisura gigi merupakan daerah rentan inisiasi karies gigi molar satu permanen yang tumbuh pada usia 6 tahun anak belum bisa melakukan kebersihan mulutnya. Pencegahan karies dapat dilakukan dengan cara menutup pit dan fissure atau pengolesan fluor (topical fluoride application pada permukaan gigi. Tujuan penelitian ini untuk menganalisis perbedaan efektivitas fissure sealant dan topical fluoride application untuk mencegah karies gigi molar satu permanen anak

[Application of individually designed trans-fissure approach in brain surgery: analysis of 90 cases].

Science.gov (United States)

Zhao, Ji-Zong; Wang, Shuo; Zhang, Mao-Zhi; Wang, Lei; Wang, Rong; Tang, Ya-Juan

2009-01-06

To explore the feasibility and value of trans-fissure approaches in brain surgery through individually designed craniotomy. Ninety patients with intracranial space-occupying lesions, 47 males and 58 females, aged (43 +/- 14) (1 - 68), were treated by individualized trans-fissure approach surgeries. Linear scalp incision or "horseshoe shape" scalp incision were designed to perform the operation, with a bone flap 3 - 4 cm in diameter. The shortest approach to reach the lesion was decided under the guidance of neuro-navigation and real-time B-mode ultrasonography. Then the lesions were removed through natural cortical fissures. Another 79 patients with intracranial space-occupying lesions, 53 males and 51 females, aged (42 +/- 11) (15 -73), undergoing classical surgeries in the same period were used as control group. The average operation time, size of bone flap, amount of blood loss, hospitalization time, and hospitalization cost were compared between these 2 groups. The operation time of the individually designed trans-fissure approach group was (3.1 +/- 1.6) hours (1.33 - 10.83 hours), significantly shorter than that of the control group [(4.8 +/- 1.9) hrs, P trans-fissure approach group was (173 +/- 168) ml (20 m - 500 ml), significantly less than that of the control group [(410 +/- 61) ml, P trans-fissure approach group was (12 +/- 5) cm2 [(1 - 25) cm2], significantly smaller than that of the control group [(20. +/- 9) cm2, P trans-fissure approach group received retransfusion, compared to 15 in the control group, during operation. No infection or other significant complications occurred after operation in the individually designed trans-fissure approach group. The hospitalization time of the individually designed trans-fissure approach group was (20 +/- 6) days (9 - 39 days), significantly shorter than that of the control group [(24 +/- 7) days, P trans-fissure approach group was (23171 +/- 7280) yuan RMB; significantly lower than that of the control group

Demonstration of the pulmonary interlobar fissures on multiplanar reformatted images with 64-slices spiral CT

International Nuclear Information System (INIS)

Wang Yafei; Chen Yerong; Shan Xiuhong; Tang Zhiyang; Ni Enzhen; Huang Hao; Wu Shuchun

2009-01-01

Objective: To determine the optimal orientation and slice thickness of reformatted images to visualize the interlobar fissures on multiplanar reformation (MPR) images and to recommend MPR imaging protocal for visualizing interlobar fissures in clinical practise. Methods: 64-slices CT scans of chest were obtained in 300 patients without pulmonary diseases. Axial, sagittal and coronal images were reformatted at 1, 2, 3, 7 mm slice thickness respectively from the raw volume data. Three experienced radiologists evaluated all of the MPR images in the lung window and compared the differences in visualization of the interlohar fissures among the three reformatted orientations and at the different slice thicknesses with Fisher test and Friedman test. Results: Fissures on sagittal MPR images using 1, 2, 3, and 7 mm reformatted slice thickness appeared as a fine line and the preference value analysis showed the MPR images with a 3 mm reformatted slice thickness is the best for visualizing the interlobar fissure. Compared to the sagittal orientation, the coronal was not as good and the axial was the worst among the three orientations. The coronal images with a 3 mm reformatted slice thickness were slightly inferior to sagittal images. The right horizontal fissures were observed as a fine line in all coronal image in 94.0% (282)of cases and in some of the images in 6.0% (18) of cases, the right oblique fissures were displayed as a fine line in coronal images in 2.3% (7) of cases and in some images in 85.0% (255) of cases, the left oblique fissures were displayed as a fine line in some coronal images in 35.7% (107) of cases and displayed as a coarse line in 64.3% (193) of cases. On axial MPR images using 3 mm reformation slice thickness, the right oblique fissures and the left oblique fissures were displayed as a fine line in some axial images in 79.3% (238) and 81.0% (243) of cases respectively, none of the images showed horizontal fissures as a fine line. There was

Hemorrhoids and anal fissures in inflammatory bowel disease.

Science.gov (United States)

D'Ugo, S; Stasi, E; Gaspari, A L; Sileri, P

2015-12-01

Perianal disease is a common complication of inflammatory bowel disease (IBD). It includes different conditions from more severe and potentially disabling ones, such as abscesses and fistulas, to more benign conditions such as hemorrhoids, skin tags and fissures. Most literature has been focused on anal sepsis and fistulae, as they carry the majority of disease burden and often alter the natural course of the disease. Hemorrhoids and anal fissures in patients with IBD have been overlooked, although they can represent a challenging problem. The management of hemorrhoids and fissures in IBD patients may be difficult and may significantly differ compared to the non-affected population. Historically surgery was firmly obstructed, and hemorrhoidectomy or sphincterotomy in patients with associated diagnosis of IBD was considered harmful, although literature data is scant and based on small series. Various authors reported an incidence of postoperative complications higher in IBD than in the general populations, with potential severe events. Considering that a spontaneous healing is possible, the first line management should be a medical therapy. In patients non-responding to conservative measures it is possible a judicious choice of surgical options on a highly selective basis; this can lead to acceptable results, but the risk of possible complications needs to be considered. In this review it is analyzed the current literature on the incidence, symptoms and treatment options of hemorrhoids and anal fissures in patients with Crohn's disease and ulcerative colitis.

New diagnostic technology and hidden pits and fissures caries

OpenAIRE

Fabrizio Guerra; Marta Mazur; Francesca Rinaldo; Denise Corridore; Daniele Salvi; Debora Pasqualotto; Gianna Maria Nardi; Livia Ottolenghi

2015-01-01

The accuracy in pits and fissures caries detection is of paramount importance in dental caries primary and secondary prevention. A combination of visual examination and probing is currently the mainstay of occlusal caries diagnosis. Unfortunately, these types of inspection alone may leave a certain number of pit and fissure caries undetected. The Vista Cam iX fluorescence camera (Durr Dental, Bietigheim-Bissingen, Germany) is a novel dental diagnostic tool for quantitative assessment of denta...

Orientation of the eruption fissures controlled by a shallow magma chamber in Miyakejima

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Nobuo Geshi

2016-11-01

Full Text Available Orientation of the eruption fissures and composition of the lavas of the Miyakejima volcano indicate tectonic influence of a shallow magma chamber on the distribution of eruption fissures. We examined the distributions and magmatic compositions of 23 fissures that formed within the last 2800 years, based on a field survey and a new dataset of 14C ages. The dominant orientation of the eruption fissures in the central portion of the volcano was found to be NE-SW, which is perpendicular to the direction of regional maximum horizontal compressive stress (σHmax. Magmas that show evidences of magma mixing between basaltic and andesitic magmas erupted mainly from the eruption fissures with a higher offset angle from the regional σHmax direction. The presence of a shallow dike-shaped magma chamber controls the distribution of the eruption fissures. The injection of basaltic magma into the shallow andesitic magma chamber caused the temporal rise of internal magmatic pressure in the shallow magma chamber. Dikes extending from the andesitic magma chamber intrude along the local compressive stress field which is generated by the internal excess pressure of the andesitic magma chamber. As the result, the eruption fissures trend parallel to the elongation direction of the shallow magma chamber. Injection of basaltic magma into the shallow andesitic magma chamber caused the magma mixing. Some basaltic dikes from the deep-seated magma chamber reach the ground surface without intersection with the andesitic magma chamber. The patterns of the eruption fissures can be modified in the future as was observed in the case of the destruction of the shallow magma chamber during the 2000 AD eruption.

Fissure formation in coke. 2: Effect of heating rate, shrinkage and coke strength

Energy Technology Data Exchange (ETDEWEB)

D.R. Jenkins; M.R. Mahoney [CSIRO, North Ryde, NSW (Australia). Mathematical and Information Sciences

2010-07-15

We investigate the effects of the heating rate, coke shrinkage and coke breakage strength upon the fissure pattern developed in a coke oven charge during carbonisation. This is done principally using a mechanistic model of the formation of fissures, which considers them to be an array of equally spaced fissures, whose depth follows a 'period doubling' pattern based upon the time history of the fissures. The model results are compared with pilot scale coke oven experiments. The results show that the effect of heating rate on the fissure pattern is different to the effect of coke shrinkage, while the effect of coke breakage strength on the pattern is less pronounced. The results can be seen in both the shape and size of resulting coke lumps after stabilisation. The approach gives the opportunity to consider means of controlling the carbonisation process in order to tune the size of the coke lumps produced. 7 refs., 18 figs., 4 tabs.

Søvind Marl - Behaviour of a plastic fissured Eocene clay

DEFF Research Database (Denmark)

Grønbech, Gitte Lyng

The thesis regards the characterisation and determination of properties of Søvind Marl, a Danish highly fissured and plastic clay. Highly fissured, plastic clays are present at great depths several places in Denmark, where extensive development activity is currently ongoing. Nonetheless...... will determine the correlation factors from field tests to undrained shear strength. Finally, the thesis is concluded with recommendations for further work within the field of plastic clays....

Incomplete fissures in severe emphysematous patients evaluated with MDCT: Incidence and interobserver agreement among radiologists and pneumologists

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Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Neuenheimer Feld 110, 69120 Heidelberg (Germany); Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstr. 5,69126 Heidelberg (Germany); Department of Radiology, University Hospital of the School of Medicine of Ribeirao Preto - University of Sao Paulo, Av. Bandeirantes 3900, Campus Universitario Monte Alegre, 14048 900 Ribeirao Preto, SP (Brazil); Puderbach, Michael [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Neuenheimer Feld 110, 69120 Heidelberg (Germany); Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstr. 5,69126 Heidelberg (Germany); Gompelmann, Daniela; Eberhardt, Ralf; Herth, Felix [Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstr. 5,69126 Heidelberg (Germany); Kauczor, Hans-Ulrich [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Neuenheimer Feld 110, 69120 Heidelberg (Germany); Heussel, Claus Peter [Department of Diagnostic and Interventional Radiology, University of Heidelberg, Neuenheimer Feld 110, 69120 Heidelberg (Germany); Chest Clinic (Thoraxklinik), University of Heidelberg, Amalienstr. 5,69126 Heidelberg (Germany)

2012-12-15

Objective: Pulmonary fissures completeness predicts efficacy in endobronchial valves (EBV) implantation, a new lobar volume reduction therapy for severe emphysematous patients. We assessed the incidence of incomplete fissures and the interobserver agreement in its evaluation with MDCT, in severe emphysematous patients prior to EBV implantation. Materials and Methods: Volumetric thin-section CT scans of 35 patients (CODP GOLD 3/4, heterogeneous emphysema) were retrospectively reviewed by 2 pneumologists, 1 general and 2 experienced chest radiologists, independently and blinded for treatment outcome, and the pulmonary fissures were classified as either complete or incomplete. Interobserver agreement was assessed with Kappa index (KI). Results: Agreement between all readers for the left oblique, right oblique and horizontal fissure was, respectively, moderate (KI = 0.53), fair (KI = 0.37) and moderate (KI = 0.42). Highest agreement (99/105 fissures) was observed among experienced radiologists, being for left oblique, right oblique and horizontal, respectively, almost perfect (KI = 0.79), perfect (KI = 1.0) and moderate (KI = 0.52). These 2 reviewers found that all of 35 patients had at least one incomplete fissure, with a proportion of incomplete fissures assigned as 74/65%, 85/85% and 91/88%, respectively for the left oblique, right oblique and horizontal fissures. Conclusions: Pneumologists and radiologists agreed fairly to moderately in fissures analysis, while the experienced chest radiologists reached the highest clinically adequate agreement of 94%. We believe that clinical routine visual analysis of the fissures integrity can be done with a good degree of confidence in MDCT images, and experienced readers might be required. Also, a higher than expected incidence of incomplete fissures was described in our studied population.

Incomplete fissures in severe emphysematous patients evaluated with MDCT: Incidence and interobserver agreement among radiologists and pneumologists

International Nuclear Information System (INIS)

Koenigkam-Santos, Marcel; Puderbach, Michael; Gompelmann, Daniela; Eberhardt, Ralf; Herth, Felix; Kauczor, Hans-Ulrich; Heussel, Claus Peter

2012-01-01

Objective: Pulmonary fissures completeness predicts efficacy in endobronchial valves (EBV) implantation, a new lobar volume reduction therapy for severe emphysematous patients. We assessed the incidence of incomplete fissures and the interobserver agreement in its evaluation with MDCT, in severe emphysematous patients prior to EBV implantation. Materials and Methods: Volumetric thin-section CT scans of 35 patients (CODP GOLD 3/4, heterogeneous emphysema) were retrospectively reviewed by 2 pneumologists, 1 general and 2 experienced chest radiologists, independently and blinded for treatment outcome, and the pulmonary fissures were classified as either complete or incomplete. Interobserver agreement was assessed with Kappa index (KI). Results: Agreement between all readers for the left oblique, right oblique and horizontal fissure was, respectively, moderate (KI = 0.53), fair (KI = 0.37) and moderate (KI = 0.42). Highest agreement (99/105 fissures) was observed among experienced radiologists, being for left oblique, right oblique and horizontal, respectively, almost perfect (KI = 0.79), perfect (KI = 1.0) and moderate (KI = 0.52). These 2 reviewers found that all of 35 patients had at least one incomplete fissure, with a proportion of incomplete fissures assigned as 74/65%, 85/85% and 91/88%, respectively for the left oblique, right oblique and horizontal fissures. Conclusions: Pneumologists and radiologists agreed fairly to moderately in fissures analysis, while the experienced chest radiologists reached the highest clinically adequate agreement of 94%. We believe that clinical routine visual analysis of the fissures integrity can be done with a good degree of confidence in MDCT images, and experienced readers might be required. Also, a higher than expected incidence of incomplete fissures was described in our studied population.

Isotope techniques in the study of the hydrology of fractured and fissured rocks

International Nuclear Information System (INIS)

1989-01-01

It is generally agreed that the hydrology of fractured rocks refers to the occurrence and movement of groundwater in rocks whose porosity is due to cracks, fissures and fractures in compact rocks. Until recently, crystalline rocks were considered to be impervious (the role of karst reservoirs for groundwater storage is already known). Thus, although fractured rocks cover approximately one-third of the Earth's surface, knowledge of groundwater flow dynamics still needs to be substantively improved. The Proceedings include the papers presented at the Advisory Group Meeting on the Application of Isotope Techniques in the Study of the Hydrology of Fractured and Fissured Rocks, which took place in Vienna from 17 to 21 November 1986. The meeting was attended by 21 scientists from 10 Member States. The Group agreed that the following topics should be given the highest priority: (1) Protection of groundwater resources should be incorporated into all future activities. This implies that recharge areas have to be delineated, not only using nuclear techniques but also other hydrogeological and geochemical methods. Research efforts in this direction should be intensified. (2) The Group was aware that new isotope techniques are being developed in hydrogeology and agreed that their application in fractured and fissured rocks showed promise. It was therefore suggested that information on new isotopes such as 36 Cl and 129 I should be gathered, either in the form of the various techniques currently being used by different laboratories or through the various activities that are being undertaken. Ways of co-ordinating the work being done and exchanging information at the international level should be encouraged. The Proceedings should be of interest to scientists responsible for the evaluation of water resources in crystalline rocks. It is hoped that hydrologists and hydrogeologists working in such terrains who are not familiar with the use of isotope techniques will find ideas and

Calcul statistique du volume des blocs matriciels d'un gisement fissuré The Statistical Computing of Matrix Block Volume in a Fissured Reservoir

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Guez F.

2006-11-01

Full Text Available La recherche des conditions optimales d'exploitation d'un gisement fissuré repose sur une bonne description de la fissuration. En conséquence il est nécessaire de définir les dimensions et volumes des blocs matriciels en chaque point d'une structure. Or la géométrie du milieu (juxtaposition et formes des blocs est généralement trop complexe pour se prêter au calcul. Aussi, dans une précédente communication, avons-nous dû tourner cette difficulté par un raisonnement sur des moyennes (pendages, azimuts, espacement des fissures qui nous a conduits à un ordre de grandeur des volumes. Cependant un volume moyen ne peut pas rendre compte d'une loi de répartition des volumes des blocs. Or c'est cette répartition qui conditionne le choix d'une ou plusieurs méthodes successives de récupération. Aussi présentons-nous ici une méthode originale de calcul statistique de la loi de distribution des volumes des blocs matriciels, applicable en tout point d'un gisement. La part de gisement concernée par les blocs de volume donné en est déduite. La connaissance générale du phénomène de la fracturation sert de base au modèle. Les observations de subsurface sur la fracturation du gisement en fournissent les données (histogramme d'orientation et d'espacement des fissures.Une application au gisement d'Eschau (Alsace, France est rapportée ici pour illustrer la méthode. The search for optimum production conditions for a fissured reservoir depends on having a good description of the fissure pattern. Hence the sizes and volumes of the matrix blocks must be defined at all points in a structure. However, the geometry of the medium (juxtaposition and shapes of blocks in usually too complex for such computation. This is why, in a previous paper, we got around this problem by reasoning on the bases of averages (clips, azimuths, fissure spacing, and thot led us to an order of magnitude of the volumes. Yet a mean volume cannot be used to explain

Fissure fillings from the Klipperaas study site

International Nuclear Information System (INIS)

Tullborg, E.L.

1986-07-01

The Klipperaas study site is located within the Smaaland-Vaermland granitoid belt in southern Sweden. The area investigated can be subdivided into blocks with different hydraulic character and fracture frequency of the rocks. A fissure filling, study has been carried out within the area. This includes identification of the minerals, mineral frequency, textures within the fissures and isotope analyses of calcites. Four generation of fissure fillings, within the time space c. 1600 M.a. to present, has been distinguished. These are 1) quartz; 2) epidote + muscovite and adularia + hematite; 3) calcite + chlorite +/hematite; 4) calcite, clay minerals and Fe-oxyhydroxide. It is observed that the surface water affect the uppermost part of the bedrock resulting in calcite dissolution, break down of pyrite and precipitation of Fe-oxyhydroxide. It is also obvious from the fracture calcite frequency that calcite dissolution is more intensive close to and within the fracture zones. There, Fe-oxyhydroxide can be found down to at least 400 m depth. This gives valuable information about the physic-chemical character of the groundwater within the bedrock. Several fracture zones have been reactivated. It is also suspected that relatively late movements have taken place causing crushing of the rock and only a slight cementation of the crushed material is visible. Some of the fracture zones correspond to mafic dikes. These zones exhibit lower hydraulic conductivity than other zones due to fracture sealing by clay minerals but also by chlorite and calcite. (author)

Cutting Whole Length or Partial Length of Internal Anal Sphincter in Managementof Fissure in Ano

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Furat Shani Aoda

2017-12-01

Full Text Available A chronic anal fissure is a common painful perianal condition.The main operative procedure to treat this painful condition is a lateral internal sphincteretomy (LIS.The aim of study is to compare the outcome and complications of closed LIS up to the dentate line (whole length of internal sphincter or up to the fissure apex (partial length of internal sphincter in the treatment of anal fissure.It is a prospective comparativestudy including 100 patients with chronic fissure in ano. All patients assigned to undergo closed LIS. Those patients were randomly divided into two groups: 50 patients underwent LIS to the level of dentate line (whole length and other 50 patients underwent LIS to the level of fissure apex (partial length. Patients were followed up weekly in the 1st month, twice monthly in the second month then monthly   for next 2 months and finally after 1 year. There was satisfactory relief of pain in all patients in both groups & complete healing of the fissure occurred. Regarding post operative incontinence no major degree of incontinence occur in both group but minor degree of incontinence persists In 7 patients after whole length LIS after one year. In conclusion, both whole length & partial length LIS associated with improvement of pain, good chance of healing but whole length LIS associated with more chance of long term  flatus incontinence. Hence,we recommend partial length LIS as treatment forchronic anal fissure.

Abnormalities of cerebellar foliation and fissuration: classification, neurogenetics and clinicoradiological correlations

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Demaerel, P. [University Hospital, Department of Radiology, Herestraat 49, 3000 Leuven (Belgium)

2002-08-01

Several genes have been found to influence the different cells involved in the processes of foliation and fissuration in the mouse and rat cerebellum. In the light of these new concepts and on the basis of the imaging findings in 42 patients, a classification is proposed for abnormalities of foliation and fissuration. On the basis of recent genetic and experimental evidence on mechanisms which control the origin of the cerebellum, it is suggested that abnormalities of foliation and fissuration form a single group, with a spectrum of severity. Some patients have only abnormal fissuration of the anterior lobe (type 1a) and others additional dysplasia of the anterior and part of the posterior lobe (type 1b). Extension of abnormalities into the hemispheres is often seen in the latter group. A second group has vermian and hemisphere abnormalities (type 2). In addition to the malformation of the anterior lobe of the vermis, three different hemispheric lesions can be seen in this group: cortical dysgenesis, hypertrophy of the cerebellar cortex, and malorientation of the folia. The mild abnormalities (type 1a) can be considered an incidental observation without clinical relevance. The moderate and severe cerebellar anomalies (type 1b and 2) are always associated with cerebellar symptoms and/or signs. (orig.)

Abnormalities of cerebellar foliation and fissuration: classification, neurogenetics and clinicoradiological correlations

International Nuclear Information System (INIS)

Demaerel, P.

2002-01-01

Several genes have been found to influence the different cells involved in the processes of foliation and fissuration in the mouse and rat cerebellum. In the light of these new concepts and on the basis of the imaging findings in 42 patients, a classification is proposed for abnormalities of foliation and fissuration. On the basis of recent genetic and experimental evidence on mechanisms which control the origin of the cerebellum, it is suggested that abnormalities of foliation and fissuration form a single group, with a spectrum of severity. Some patients have only abnormal fissuration of the anterior lobe (type 1a) and others additional dysplasia of the anterior and part of the posterior lobe (type 1b). Extension of abnormalities into the hemispheres is often seen in the latter group. A second group has vermian and hemisphere abnormalities (type 2). In addition to the malformation of the anterior lobe of the vermis, three different hemispheric lesions can be seen in this group: cortical dysgenesis, hypertrophy of the cerebellar cortex, and malorientation of the folia. The mild abnormalities (type 1a) can be considered an incidental observation without clinical relevance. The moderate and severe cerebellar anomalies (type 1b and 2) are always associated with cerebellar symptoms and/or signs. (orig.)

Retention of fissure sealants in young permanent molars affected by dental fluorosis: a 12-month clinical study.

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Hasanuddin, S; Reddy, E R; Manjula, M; Srilaxmi, N; Rani, S T; Rajesh, A

2014-10-01

To evaluate and compare retention and caries occurance following placement of Clinpro and FUJI VII fissure sealants, by two different techniques simultaneously in unsealed, contralateral young permanent molars of 7- to 10-year-old children affected by mild to moderate dental fluorosis at various recall intervals of 1 week, 1, 3, 6 and 12 months. 80 schoolchildren with mild to moderate dental fluorosis were assigned to Group A and Group B with 40 children in each group. In Group A Clinpro fissure sealant and in Group B Fuji VII fissure sealant was used. In both the groups fissure sealants were applied by conventional fissure sealant technique (CST) on one side and enameloplasty sealant technique (EST) on the other side of the same arch. The applied fissure sealants were evaluated clinically for retention and caries incidence. Clinpro fissure sealant showed a retention rate of 95% when compared with Fuji VII (57.5%) at the end of 12 months, which was statistically significant. Regarding techniques, EST showed better results than CST in both the groups. Comparison of groups with respect to retention and techniques at different time periods was performed using Mann-Whitney U test (p < 0.05). Comparison of different time periods with respect to retention and technique in all the groups was performed using Wilcoxon matched pairs test by ranks (p < 0.05). Clinpro fissure sealant showed better retention at all treatment intervals, when compared with Fuji VII. Further follow-up is required to study the efficacy of the fissure sealant placement techniques.

Traumatic superior orbital fissure syndrome: assessment of cranial nerve recovery in 33 cases.

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Chen, Chien-Tzung; Wang, Theresa Y; Tsay, Pei-Kwei; Huang, Faye; Lai, Jui-Pin; Chen, Yu-Ray

2010-07-01

Superior orbital fissure syndrome is a rare complication that occurs in association with craniofacial trauma. The characteristics of superior orbital fissure syndrome are attributable to a constellation of cranial nerve III, IV, and VI palsies. This is the largest series describing traumatic superior orbital fissure syndrome that assesses the recovery of individual cranial nerve function after treatment. In a review from 1988 to 2002, 33 patients with superior orbital fissure syndrome were identified from 11,284 patients (0.3 percent) with skull and facial fractures. Severity of cranial nerve injury and functional recovery were evaluated by extraocular muscle movement. Patients were evaluated on average 6 days after initial injury, and average follow-up was 11.8 months. There were 23 male patients. The average age was 31 years. The major mechanism of injury was motorcycle accident (67 percent). Twenty-two received conservative treatment, five were treated with steroids, and six patients underwent surgical decompression of the superior orbital fissure. After initial injury, cranial nerve VI suffered the most damage, whereas cranial nerve IV sustained the least. In the first 3 months, recovery was greatest in cranial nerve VI. At 9 months, function was lowest in cranial nerve VI and highest in cranial nerve IV. Eight patients (24 percent) had complete recovery of all cranial nerves. Functional recovery of all cranial nerves reached a plateau at 6 months after trauma. Cranial nerve IV suffered the least injury, whereas cranial nerve VI experienced the most neurologic deficits. Cranial nerve palsies improved to their final recovery endpoints by 6 months. Surgical decompression is considered when there is evidence of bony compression of the superior orbital fissure.

The effect of fissures on the strength of structural timber

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Íñiguez, Guillermo

2010-06-01

Full Text Available Detailed measurements of drying fissures were carried out on 28 pieces of gross cross-section structural Scots pine timber. Different parameters have been proposed to measure their magnitude: length, depth, thickness and slope of grain, as well as an index of area in the neutral axis plane (ratio of effective to total surface. The parameters of fissures have been related to bending strength, shear strength, modulus of elasticity and rupture energy obtained from mechanical tests, considering whether rupture is due to bending or shear. All of the fissures observed allows to classify the pieces as MEG according to the UNE 56544 standard. To quantify the magnitude of fissures the index of areas is proposed, while mechanical properties can be quantified by rupture energy. Analysis of the results does not show any relation between the fissures analyzed and the mode of failure, their magnitude and mechanical properties..

Se han realizado mediciones detalladas de las fendas de secado en 28 piezas de madera de pino silvestre de gran escuadría. Se han propuesto diferentes parámetros para medir su magnitud en longitud, profundidad, grosor e inclinación, así como un índice de áreas en el plano medio de rasante (superficie eficaz respecto a superficie total. Se han relacionado los parámetros de fendas con resistencia a flexión, resistencia a cortante, módulo de elasticidad y energía de rotura obtenidos mediante ensayos mecánicos, teniendo en cuenta si la rotura se produce por flexión o por cortante. Todas las fendas observadas permiten clasificar las piezas como MEG según la norma UNE 56544. Se propone cuantificar las fendas mediante el índice de áreas y las propiedades mecánicas mediante la energía de rotura. El análisis realizado no muestra una relación significativa entre las fendas analizadas, los modos de rotura o las propiedades mecánicas.

THE EFFECT OF FISSURES IN DOLOMITE ROCK MASS ON BLASTING PROJECTS

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Branko Božić

1989-12-01

Full Text Available Rock fractures in the form of fissures are one of more important geological features of a tectonic system. They have an effect on mechanical behaviour of rook masses exposed to the actions of surface forces. For exploitation in dolomite quarries carried out by blasting of deep shot holes it is important to know the system of fissures within a rock mass for the rock brakes along already weakened planes (the paper is published in Croatian.

Thermomechanical behavior of mica layers with lenticular fissures

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Yang, Michael Xinyi

The thermomechanical behavior of natural phlogopite mica specimens from seven different origins is characterized. An initial heat treatment, to a temperature between 300°C and 400°C, is found to form fissures that stabilize in the material. Following the initial heat treatment, all the phlogopite specimens, regardless of their origin and polytype, exhibit the extraordinarily large thermal expansion (intumescence), more than 200% at 600°C, in the direction perpendicular to the basal planes. This phenomenon is strictly reproducible when tested under a range of thermal conditions including thermal shock, multiple thermal fatigue cycles, varying heating or cooling rates and isothermal heating over an extensive period of time at different temperatures up to 585°C. The hysteresis, associated with the thermal cycle, is increased when the specimen is heated or cooled at a faster rate. The maximum coefficient of linear thermal expansion, approximately 10 -2°C-1, is observed over the temperature range 100--120°C. This is due to the non-structural water, entrapped within the layer structure, which undergoes a phase transition and causes the mica layers to expand abruptly. A model of lenticular fissures is developed based on thin-plate mechanics and thermodynamics assumptions. The state of a lenticular fissure with water vapor molecules is determined to correlate the experimental parameters with the material properties. The average density of water vapor molecules within a lenticular fissure is calculated to be ˜1025 m 3 for the temperature interval between 100°C and 275°C. The concentration of non-structure water, based on the model calculation, is less than 0.1% by weight. Acoustic emission (AE) signals have been reported by Pranevicius et al. (1995) to correspond to the microstructure changes as the internal lenticular fissures develop in phlogopite. This technique has also been proven feasible to characterize the thermomechanical behavior of other layer structures

The economics of pit and fissure sealants in preventive dentistry: a review.

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Kitchens, Dinah H

2005-08-15

Oral diseases are progressive, cumulative, and become more intricate to treat with advancement. While dental caries is an infectious transmissible disease with children being at the highest risk, primary prevention can reduce this risk. Primary prevention in dentistry is usually considered to be community fluoridated water supplies, professional fluoride treatments, and pit and fissure sealants. While community fluoridated water supplies have been proven to be cost-effective, the cost-effectiveness of pit and fissure sealants has primarily been studied in school-based programs of children from low socio-economic backgrounds. Dental sealant programs are just one way to help increase primary prevention in the oral health disparities of children. The purpose of this paper is to review the literature regarding the cost-effectiveness of pit and fissure sealants as a preventive strategy in preventive dentistry.

Subpial Hematoma and Extravasation in the Interhemispheric Fissure with Subarachnoid Hemorrhage

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Matsuoka, Go; Abe, Kayoko; Okada, Yoshikazu; Sakai, Shuji

2015-01-01

A recent report on computed tomography (CT) findings of contrast extravasation in subarachnoid hemorrhage (SAH) with Sylvian hematoma suggests that the occurrence of the hematoma is secondary to bleeding in the subpial space. Our patient was in his sixties and was admitted to the hospital because of loss of consciousness (Glasgow Coma Scale E4V1M4). SAH was diagnosed in plain head CT, and growing hematomas were observed in the Sylvian and interhemispheric fissures following a subarachnoid hemorrhage. CT angiography (CTA) using a dual-phase scan protocol revealed contrast extravasation in both the fissures in the latter phase, and hematoma in the interhemispheric fissure contained multiple bleeding points. This case indicates that the occurrence of subpial hematoma such as Sylvian hematoma can be a secondary event following subpial bleeding from damaged small vessels elsewhere in the cranium. Instead of four-dimensional (4D) CT, the dual-phase CTA technique may help detect minor extravasations with usual helical CT scanner. PMID:25963159

Numerical analysis on the crack propagation and failure characteristics of rocks with double fissures under the uniaxial compression

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Leyong Chen

2015-12-01

Full Text Available The fissures and rock bridges with different dips had different contributions to crack's initiation, propagation, convergence and penetration. In this paper, based on the rock fracture theory, the crack's propagation and evolution process on rock specimen with double fissures under uniaxial compression was simulated. As a result, the crack propagation and evolution law of rocks with different fissure dips (α = 0°, 15°, 30°, 45°, 60°, 75°, 90°; β = 45° and different rock bridge dips (β = 0°, 30°, 45°, 60°, 90°; α = 45° was obtained by numerical tests. Meanwhile, the fissure and rock bridge dips influence on the macro mechanical properties of rock was analyzed. Besides, the paper investigated the influences of different fissure dips and different rock bridge dips on the bridge transfixion. The study is of great significance to reveal the impact of different dips on the mechanical mechanism of multiple-fissures rock under specific conditions, and it also has important theoretical significance for the research on multiple-fissure rock.

Land subsidence, Ground Fissures and Buried Faults: InSAR Monitoring of Ciudad Guzmán (Jalisco, Mexico

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Carlo Alberto Brunori

2015-07-01

Full Text Available We study land subsidence processes and the associated ground fissuring, affecting an active graben filled by thick unconsolidated deposits by means of InSAR techniques and fieldwork. On 21 September 2012, Ciudad Guzmán (Jalisco, Mexico was struck by ground fissures of about 1.5 km of length, causing the deformation of the roads and the propagation of fissures in adjacent buildings. The field survey showed that fissures alignment is coincident with the escarpments produced on 19 September 1985, when a strong earthquake with magnitude 8.1 struck central Mexico. In order to detect and map the spatio-temporal features of the processes that led to the 2012 ground fissures, we applied InSAR multi-temporal techniques to process ENVISAT-ASAR and RADARSAT-2 satellite SAR images acquired between 2003 and 2012. We detect up to 20 mm/year of subsidence of the northwestern part of Ciudad Guzmán. These incremental movements are consistent with the ground fissures observed in 2012. Based on interferometric results, field data and 2D numerical model, we suggest that ground deformations and fissuring are due to the presence of areal subsidence correlated with variable sediment thickness and differential compaction, partly driven by the exploitation of the aquifers and controlled by the distribution and position of buried faults.

In Vitro Comparison of Microleakage of Two Materials Used as Pit and Fissure Sealants

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Zahra Bahrololoomi

2011-09-01

Full Text Available Background and aims. Marginal seal of the material is extremely important in fissure sealant therapy. The aim of this study was to investigate microleakage of flowable composite resins and conventional fissure sealants with or without dentin bonding agent. Materials and methods. The occlusal surface of 60 intact extracted human premolars, divided into four groups, were cleaned with pumice/slurry, etched with 37% phosphoric acid for 15 seconds, rinsed and dried. Groups were treated differently: Excite bonding agent followed by Helioseal F fissure sealant in group1; Helioseal F alone in group 2; Excite bonding agent followed by Tetric Flow in group 3; and Tetric Flow alone in group 4. Light-curing was done after each application. After thermocycling, the whole surface of each specimen was coated with nail varnish except for one millimeter around the fissure sealant. The teeth were immersed in 2% basic fuchsin for 24 hours and then sectioned buccolingually. The sections were analyzed for leakage under a stereomicroscope. Data was analyzed by Kruskal-Wallis and Mann-Whitney tests at a significance level of P 0.05, except for groups 2 and 4 (P = 0.002 and groups 3 and 4 (P = 0.033. Conclusion. Use of a flowable composite with bonding agent is a good alternative for sealing pits and fissures; however, further in vitro and in vivo studies are necessary.

Comparison of various concentrations of tricalcium phosphate nanoparticles on mechanical properties and remineralization of fissure sealants.

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Sara Tavassoli-Hojjati

2014-08-01

Full Text Available The aim of this study was to investigate the mechanical properties (flexural strength, micro-shear bond strength and remineralizing potential of fissure sealants by adding various concentrations of β-tricalcium phosphate nanoparticles.This in-vitro study consisted of five experimental groups containing prepared nano-fisssure sealants (1-5 wt.% β-TCP nanoparticles and two control groups containing a prepared and a commercial fissure sealant. Flexural/micro-shear bond strength values were measured using Zwick test machine. Cavities on sixty healthy premolar teeth were filled with the fissure sealants containing 0-5 wt.% of nano β-TCP. The samples were assessed for remineralization under scanning electron microscopy (SEM and EDAX. Kolmogorov-Smirnov test, One-way ANOVA and Tukey's Post Hoc analysis/HSD were used to analyze the data.There was no significant difference between the flexural strengths/elastic modulus of the 0-5 wt.% nano β-TCP groups (p>0.05. The average flexural strength/elastic modulus of the prepared fissure sealant group (0% was significantly higher than the commercial fissure sealant group (Clinpro (p0.05. Examining the samples under SEM showed a significant increase in thickness of the intermediate layer with increasing concentrations of β-TCP nanoparticles (p<0.05.Addition of 1-5 wt.% β-TCP nanoparticles to the fissure sealants significantly increased the remineralization potential without affecting the mechanical properties.

A model of hydrological and mechanical feedbacks of preferential fissure flow in a slow-moving landslide

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D. M. Krzeminska

2013-03-01

Full Text Available The importance of hydrological processes for landslide activity is generally accepted. However, the relationship between precipitation, hydrological responses and movement is not straightforward. Groundwater recharge is mostly controlled by the hydrological material properties and the structure (e.g., layering, preferential flow paths such as fissures of the unsaturated zone. In slow-moving landslides, differential displacements caused by the bedrock structure complicate the hydrological regime due to continuous opening and closing of the fissures, creating temporary preferential flow paths systems for infiltration and groundwater drainage. The consecutive opening and closing of fissure aperture control the formation of a critical pore water pressure by creating dynamic preferential flow paths for infiltration and groundwater drainage. This interaction may explain the seasonal nature of the slow-moving landslide activity, including the often observed shifts and delays in hydrological responses when compared to timing, intensity and duration of precipitation. The main objective of this study is to model the influence of fissures on the hydrological dynamics of slow-moving landslide and the dynamic feedbacks between fissures, hydrology and slope stability. For this we adapt the spatially distributed hydrological and slope stability model (STARWARS to account for geotechnical and hydrological feedbacks, linking between hydrological response of the landside and the dynamics of the fissure network and applied the model to the hydrologically controlled Super-Sauze landslide (South French Alps.

Microleakage, adaptation ability and clinical efficacy of two fluoride releasing fissure sealants

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Marković Dejan

2012-01-01

Full Text Available Background/Aim. Retention of fissure sealants and good adaptation to enamel are essential for their success. Fluoride releasing resin-based materials are widely accepted for pit and fissure sealing, but newly designed glass ionomers can serve as a good alternative. The aim of this study was to evaluate microleakage and sealing ability in vitro, and to clinically assess two fluoride releasing fissure sealants. Methods. The sample for experimental study consisted of 20 freshly extracted intact human third molars, divided in two experimental groups according to the sealing material: fluoride releasing resin-based (Heliosel F and glass ionomer (Fuji Triage material. Digital images and scanning electron microscope were used to assess microleakage and adaptation ability. Sample for clinical study consisted of 60 children, aged 6-8 years, with high caries risk, divided in two groups according to the sealant material. Fissure sealant was applied to all erupted, caries-free first permanent molars. Sealants were evaluated after 3, 6 and 12 months using modified Ryge criteria for retention, marginal adaptation, colour match, surface smoothness and caries. Results. Microleakage was detected in more than half of the specimen, without significant differences between the two groups (p > 0.05. Both materials exhibited acceptable sealing ability. Complete retention at the end of the observation period was 81.8% for resin-based, and 21.1% for glass-ionomer fissure sealant (p < 0.001. The presence of caries in sealed molars has been detected in one patient in both groups. During the 12-month observation period, Helioseal F demonstrated better retention, marginal adaptation and surface smoothness (p < 0.001. There were no differences between the two materials regarding caries and color match (p > 0.05. Conclusion. Both tested materials demonstrate satisfactory clinical and caries prophylactic characteristics that justify their use in contemporary preventive

An MR study on widening of the anterior cerebral longitudinal fissure in patients with schizophrenia

International Nuclear Information System (INIS)

Yoshizawa, Masao; Nagumo, Ichiro; Kimura, Hiroko; Yamamoto, Setsuko; Kumagai, Hideo; Ito, Hisao.

1994-01-01

One-hundred and four schizophrenics and 27 normal controls underwent magnetic resonance imaging. The angles of the anterior cerebral longitudial (ACL) fissure on T 1 weighted images were measured on the axial slices at the level of the third ventricle. The schizophrenics had significantly larger angles of ACL fissure than controls. However, the effect of aging might be associated with this phenomenon. There was no correlation between subtype of schizophrenia and the augment of the fissure angle, nor correlation between the duration of schizophrenia and that augment. From this study, it can be concluded that if the fissure angle is larger than 12 degree the finding is regarded as abnormal, because 95% confidence region of the control group was at 11.1 degree. Twenty two schizophrenics revealed the findings and great majority of these patients were suffering from emotional withdrawal and blunted affect. (author)

Earth Pressure at rest of Søvind Marl – a highly overconsolidated Eocene clay

DEFF Research Database (Denmark)

Grønbech, Gitte Lyng; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

2016-01-01

The present study evaluated earth pressure at rest, K0, in highly overconsolidated Eocene clay called Søvind Marl, which exhibits extremely high plasticity indices of up to 300%, a highly fissured structure, and preconsolidation stresses up to 6,800 kPa. Continuous Loading Oedometer (CLO) tests...

Injectabilite des coulis de ciment dans des milieux fissures

Science.gov (United States)

Mnif, Thameur

Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

Fissure formation in coke. 3: Coke size distribution and statistical analysis

Energy Technology Data Exchange (ETDEWEB)

D.R. Jenkins; D.E. Shaw; M.R. Mahoney [CSIRO, North Ryde, NSW (Australia). Mathematical and Information Sciences

2010-07-15

A model of coke stabilization, based on a fundamental model of fissuring during carbonisation is used to demonstrate the applicability of the fissuring model to actual coke size distributions. The results indicate that the degree of stabilization is important in determining the size distribution. A modified form of the Weibull distribution is shown to provide a better representation of the whole coke size distribution compared to the Rosin-Rammler distribution, which is generally only fitted to the lump coke. A statistical analysis of a large number of experiments in a pilot scale coke oven shows reasonably good prediction of the coke mean size, based on parameters related to blend rank, amount of low rank coal, fluidity and ash. However, the prediction of measures of the spread of the size distribution is more problematic. The fissuring model, the size distribution representation and the statistical analysis together provide a comprehensive capability for understanding and predicting the mean size and distribution of coke lumps produced during carbonisation. 12 refs., 16 figs., 4 tabs.

A method for the automatic quantification of the completeness of pulmonary fissures: evaluation in a database of subjects with severe emphysema

Energy Technology Data Exchange (ETDEWEB)

Rikxoort, Eva M. van; Goldin, Jonathan G.; Galperin-Aizenberg, Maya; Abtin, Fereidoun; Kim, Hyun J.; Lu, Peiyun; Shaw, Greg; Brown, Matthew S. [University of California-Los Angeles, Center for Computer Vision and Imaging Biomarkers and Thoracic Imaging Research Group, Department of Radiological Sciences, David Geffen School of Medicine, Los Angeles, CA (United States); Ginneken, Bram van [Radboud University Nijmegen Medical Centre, Diagnostic Image Analysis Group, Department of Radiology, Nijmegen (Netherlands); University Medical Center Utrecht, Image Sciences Institute, Department of Radiology, Utrecht (Netherlands)

2012-02-15

To propose and evaluate a technique for automatic quantification of fissural completeness from chest computed tomography (CT) in a database of subjects with severe emphysema. Ninety-six CT studies of patients with severe emphysema were included. The lungs, fissures and lobes were automatically segmented. The completeness of the fissures was calculated as the percentage of the lobar border defined by a fissure. The completeness score of the automatic method was compared with a visual consensus read by three radiologists using boxplots, rank sum tests and ROC analysis. The consensus read found 49% (47/96), 15% (14/96) and 67% (64/96) of the right major, right minor and left major fissures to be complete. For all fissures visually assessed as being complete the automatic method resulted in significantly higher completeness scores (mean 92.78%) than for those assessed as being partial or absent (mean 77.16%; all p values <0.001). The areas under the curves for the automatic fissural completeness were 0.88, 0.91 and 0.83 for the right major, right minor and left major fissures respectively. An automatic method is able to quantify fissural completeness in a cohort of subjects with severe emphysema consistent with a visual consensus read of three radiologists. (orig.)

Radon transport processes below the earth's surface

International Nuclear Information System (INIS)

Wilkening, M.

1980-01-01

Processes by which 222 Rn is transported from the soil to the earth's surface are reviewed. The mechanisms effective in transporting 222 Rn to the surface are related to the size and configuration of the spaces occupied by the soil gas which may vary from molecular interstices to large underground caverns. The near-surface transport processes are divided into two categories: (1) a microscopic process that includes molecular diffusion and viscous flow in fine capillaries and (2) macroscopic flow in fissures and channels. Underground air rich in 222 Rn can also reach the surface through cracks, fissures, and underground channels. This type of transport is shown for (1) a horizontal tunnel penetrating a fractured hillside, (2) a large underground cave, and (3) volcanic activity. Pressure differentials having various natural origins and thermal gradients are responsible for the transport in these examples. 222 Rn transport by ordinary molecular diffusion appears to be the dominant process

Pit and fissure sealants versus fluoride varnishes for preventing dental decay in children and adolescents

DEFF Research Database (Denmark)

Hiiri, Anne; Ahovuo-Saloranta, Anneli; Nordblad, Anne

2010-01-01

the effectiveness of pit and fissure sealants to be statistically significantly higher than an application of fluoride varnish every 6 months in preventing occlusal decays of first molars at 23 months (with a RR of 0.74, 95% confidence interval (CI) 0.58 to 0.95); and at 4 years and 9 years (with a RR of 0.42, 95...... caries on the fluoride varnished tooth surfaces, compared to sealed plus fluoride varnished surfaces, with a RR of 0.36 (95% CI 0.21 to 0.61). AUTHORS' CONCLUSIONS: There was some evidence on the superiority of pit and fissure sealants over fluoride varnish application in the prevention of occlusal......BACKGROUND: The majority of the detected increment in dental caries among children and adolescents is confined to pit and fissure surfaces of first molars. OBJECTIVES: The objective of this study was to compare the effectiveness of pit and fissure sealants with fluoride varnishes in the prevention...

Pit and fissure sealants for preventing dental decay in permanent teeth

DEFF Research Database (Denmark)

Ahovuo-Saloranta, Anneli; Forss, Helena; Walsh, Tanya

2017-01-01

to 3 August 2016), and Embase Ovid (1980 to 3 August 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 3 August 2016. No restrictions were placed on language or date of publication. Selection criteria......Background: Dental sealants were introduced in the 1960s to help prevent dental caries, mainly in the pits and fissures of occlusal tooth surfaces. Sealants act to prevent bacteria growth that can lead to dental decay. Evidence suggests that fissure sealants are effective in preventing caries....... Further research with long follow-up is needed....

Effect of an Antibacterial Monomer on the Antibacterial Activity of a Pit-and-Fissure Sealant.

Directory of Open Access Journals (Sweden)

Fan Yu

Full Text Available Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea; a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™, a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05, whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane

A COMPARATIVE STUDY OF LATERAL SPHINCTEROTOMY AND LOCAL APPLICATION OF 2% DILTIAZEM GEL IN TREATMENT OF CHRONIC ANAL FISSURE

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Rajashekar

2015-11-01

Full Text Available BACKGROUND AND OBJECTIVES Anal fissures are commonly encountered in routine colorectal practice. Chronic fissures have traditionally been treated surgically. Developments in the pharmacological understanding of the internal anal sphincter have resulted in more conservative approaches towards treatment. In this study, we compare topical 2% Diltiazem gel and lateral internal sphincterotomy with respect to symptomatic relief, healing and side effects in the treatment of chronic fissure in ano. METHODS 60 patients with chronic fissure in ano were randomly divided into Diltiazem gel and internal sphincterotomy groups. Patients were followed up at weekly intervals for minimum of eight weeks. Data was recorded accordingly. RESULTS Fissure completely healed in 28(93.33% out of 30 patients treated with 2% Diltiazem gel between 4-8 weeks. Healing was 100% with internal sphincterotomy. The mean duration required for healing of fissure was 4.86 weeks in Diltiazem gel group and 3.66 weeks in internal sphincterotomy group. 61.5% patients were free from pain after treatment with Diltiazem gel whereas in internal sphicterotomy group 66.66% patients had pain relief at the end of 4 weeks. INTERPRETATION AND CONCLUSION Comparison between Diltiazem gel application and internal sphincterotomy did not show any significant difference in fissure healing and pain relief. No side effects were seen in Diltiazem gel therapy. Topical Diltiazem should be the initial treatment in chronic fissure in ano. It is better to reserve internal sphincterotomy for patients with relapse or therapeutic failure to prior pharmacological treatment.

The movement of solutes through aqueous fissures in porous rock

International Nuclear Information System (INIS)

Glueckauf, E.

1980-06-01

A mathematical treatment has been given for the movement of materials dissolved in water flowing through narrow fissures of a micro-porous substrate. As there is no water flow in these micro-pores, equilibrium between the aqueous solution and the micro-porous substrate proceeds only by diffusion, with the result that there arises a gross disequilibrium. Two major effects arise: first, the hold-up in the substrate - even when there is no adsorption taking place - is orders of magnitude larger than on non-porous substrate, and increases even further, if adsorption takes place. Secondly, dispersion caused by non-equilibrium is also orders of magnitude greater than dispersion arising from convection effects of the water flow in interconnecting fissures. As a result, the solutes arrive very much later at the end of the underground fissures, and in concentrations which are very much lower than have been calculated in previous modelling experiments. The significance of these effects is discussed in detail, and this can be helpful in the selection of sites for underground disposal of radioactive waste. It is now quite feasible to specify sites with conditions, where even solutes with minimal adsorption would not return to the surface within a million years, and where solutes of moderately strong adsorption would be effectively immobile. (author)

Homogeneity and fissure determination in uranium bars with solid state nuclear track detectors

Energy Technology Data Exchange (ETDEWEB)

Castillo, F. (Universidad Nacional Autonoma de Mexico, Mexico City. Facultad de Ciencias); Gamboa, I.; Espinosa, G.; Tapia, A. (Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Fisica); Somogyi, G. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete)

1984-01-01

A simple and efficient method for determining fissure and concentration inhomogeneity in uranium bars is the alpha-radiographic technique. In our present work uranium bars made by ININ (Mexico) were studied by using CR-39 track detectors. The space inhomogeneity in track density was measured by an optical densitometer. The presence of fissure is determined by a microfiche reader. Such a study takes only few hours and does not require sophisticated instrumentation.

Different scale land subsidence and ground fissure monitoring with multiple InSAR techniques over Fenwei basin, China

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C. Zhao

2015-11-01

Full Text Available Fenwei basin, China, composed by several sub-basins, has been suffering severe geo-hazards in last 60 years, including large scale land subsidence and small scale ground fissure, which caused serious infrastructure damages and property losses. In this paper, we apply different InSAR techniques with different SAR data to monitor these hazards. Firstly, combined small baseline subset (SBAS InSAR method and persistent scatterers (PS InSAR method is used to multi-track Envisat ASAR data to retrieve the large scale land subsidence covering entire Fenwei basin, from which different land subsidence magnitudes are analyzed of different sub-basins. Secondly, PS-InSAR method is used to monitor the small scale ground fissure deformation in Yuncheng basin, where different spatial deformation gradient can be clearly discovered. Lastly, different track SAR data are contributed to retrieve two-dimensional deformation in both land subsidence and ground fissure region, Xi'an, China, which can be benefitial to explain the occurrence of ground fissure and the correlation between land subsidence and ground fissure.

influence of drying temperature and storage duration on fissuring

African Journals Online (AJOL)

User

age duration on the cracking behaviour and head rice yield of a local rice variety - Jasmine 85. ... harvesting, processing and storage. The rice industry ... cm deep which is within the thickness consid- ered as a ..... Tracing fissure information by.

A comparison between three different pit and fissure sealants with regard to marginal integrity.

Science.gov (United States)

Fernandes, Kristlee Sabrin; Chalakkal, Paul; de Ataide, Ida de Noronha; Pavaskar, Rajdeep; Fernandes, Precylia Philo; Soni, Harleen

2012-04-01

THE AIM OF THIS STUDY IS TO COMPARE THE OCCURRENCE OF ENAMEL FRACTURES, SEALANT FRACTURES AND MARGINAL FISSURES AFTER PLACEMENT OF THREE SEALANTS: Helioseal F, Conseal F and Clinpro. Thirty individuals between 13 and 15 years of age, diagnosed with pit and fissure caries by visual and DIAGNOdent examination, were chosen for sealant placement on their mandibular molars. The sealants were placed at random, after which, impressions were made with polyvinyl siloxane and casts were fabricated. Dies were prepared, each of which were sputter coated with gold in order to be examined under a scanning electron microscope. The following morphologies were analyzed from dies from each of the sealant groups: Continuous margins, sealant fractures, marginal fissures and enamel fractures. After six months, they were recalled for impression making. Dies were prepared and microscopically analyzed as mentioned. Based on the time of evaluation, there were two groups: Initial group (soon after placement) and final group (after six months). Statistical analysis was done using the paired 't' test and One-way analysis of variance (ANOVA). Clinpro had the greatest fracture resistance, followed by Conseal F and Helioseal F. The occurrence of marginal fissure was found to be least with Clinpro.

An Experimental and Numerical Study on Cracking Behavior of Brittle Sandstone Containing Two Non-coplanar Fissures Under Uniaxial Compression

Science.gov (United States)

Yang, Sheng-Qi; Tian, Wen-Ling; Huang, Yan-Hua; Ranjith, P. G.; Ju, Yang

2016-04-01

To understand the fracture mechanism in all kinds of rock engineering, it is important to investigate the fracture evolution behavior of pre-fissured rock. In this research, we conducted uniaxial compression experiments to evaluate the influence of ligament angle on the strength, deformability, and fracture coalescence behavior of rectangular prismatic specimens (80 × 160 × 30 mm) of brittle sandstone containing two non-coplanar fissures. The experimental results show that the peak strength of sandstone containing two non-coplanar fissures depends on the ligament angle, but the elastic modulus is not closely related to the ligament angle. With the increase of ligament angle, the peak strength decreased at a ligament angle of 60°, before increasing up to our maximum ligament angle of 120°. Crack initiation, propagation, and coalescence were all observed and characterized from the inner and outer tips of pre-existing non-coplanar fissures using photographic monitoring. Based on the results, the sequence of crack evolution in sandstone containing two non-coplanar fissures was analyzed in detail. In order to fully understand the crack evolution mechanism of brittle sandstone, numerical simulations using PFC2D were performed for specimens containing two non-coplanar fissures under uniaxial compression. The results are in good agreement with the experimental results. By analyzing the stress field, the crack evolution mechanism in brittle sandstone containing two non-coplanar fissures under uniaxial compression is revealed. These experimental and numerical results are expected to improve the understanding of the unstable fracture mechanism of fissured rock engineering structures.

Mechanisms, Monitoring and Modeling Earth Fissure generation and Fault activation due to subsurface Fluid exploitation (M3EF3): A UNESCO-IGCP project in partnership with the UNESCO-IHP Working Group on Land Subsidence

Science.gov (United States)

Teatini, P.; Carreon-Freyre, D.; Galloway, D. L.; Ye, S.

2015-12-01

Land subsidence due to groundwater extraction was recently mentioned as one of the most urgent threats to sustainable development in the latest UNESCO IHP-VIII (2014-2020) strategic plan. Although advances have been made in understanding, monitoring, and predicting subsidence, the influence of differential vertical compaction, horizontal displacements, and hydrostratigraphic and structural features in groundwater systems on localized near-surface ground ruptures is still poorly understood. The nature of ground failure may range from fissuring, i.e., formation of an open crack, to faulting, i.e., differential offset of the opposite sides of the failure plane. Ground ruptures associated with differential subsidence have been reported from many alluvial basins in semiarid and arid regions, e.g. China, India, Iran, Mexico, Saudi Arabia, Spain, and the United States. These ground ruptures strongly impact urban, industrial, and agricultural infrastructures, and affect socio-economic and cultural development. Leveraging previous collaborations, this year the UNESCO Working Group on Land Subsidence began the scientific cooperative project M3EF3 in collaboration with the UNESCO International Geosciences Programme (IGCP n.641; www.igcp641.org) to improve understanding of the processes involved in ground rupturing associated with the exploitation of subsurface fluids, and to facilitate the transfer of knowledge regarding sustainable groundwater management practices in vulnerable aquifer systems. The project is developing effective tools to help manage geologic risks associated with these types of hazards, and formulating recommendations pertaining to the sustainable use of subsurface fluid resources for urban and agricultural development in susceptible areas. The partnership between the UNESCO IHP and IGCP is ensuring that multiple scientific competencies required to optimally investigate earth fissuring and faulting caused by groundwater withdrawals are being employed.

Clinical Evaluation of applying a hydrophobic and a hydrophilic bonding agent on the retention and durability of fissure sealant therapy

Directory of Open Access Journals (Sweden)

Mostafa GHandi

2016-03-01

Full Text Available Background and Aims: As in fissure sealant therapy the tooth surface is mostly enamel, the use of an enamel bonding agent (hydrophobic bonding agent may be more cost effective than that of newer generations of bonding (hydrophilic bonding agents. The aim of this study was to compare the retention and durability of fissure sealant therapy when applying an enamel bonding agent, a dentin bonding agent and no bonding agent during 4 years. Materials and Methods: This study was done on the first permanent molars of the upper and lower jaws of 24 students of the first grade of a primary school (6-7 years old. On 36 teeth, a dentin bonding agent (Excite was applied under the fissure sealant and on 36 teeth an enamel bonding agent (Margin bond was applied under the fissure sealant. Then, 24 teeth were selected from these two groups and were compared with a group (including 24 teeth with no bonding agent under the fissure sealant (as control group. All the fissures of the teeth were evaluated annually for 4 years to find out the presence or absence of fissure sealant substance. Data were analyzed using Wilcoxon test. Results: From the statistical analysis, there was no significant difference in retention and durability of the fissure sealant substance comparing the group with dentin bonding agent (Excite and the group with enamel bonding agent (Margin bond. Also, using a bonding agent made no significant difference (P>0.05. Conclusion: According to the results of this study, using a bonding agent made no improvement in the retention and durability of fissure sealant substance.

Tracer movement in a single fissure in granitic rock - some experimental results and their interpretation

International Nuclear Information System (INIS)

Neretnieks, I.; Eriksen, T.; Taetinen, P.

1980-08-01

Radionuclide migration was studied in a natural fissure in a granite core. The fissure was oriented parallel to the axis in a cylindrical core 30 cm long and 20 in diameter. The traced solution was injected at one end of the core and collected at the other. Breakthrough curves were obtained for the nonsorbing tracers tritiated water, and a large molecular weight lignosulphonate molecule and the sorbing tracers cesium and strontium. From the breakthrough curves for the nonsorbing tracers it could be concluded that channeling occurs in the single fissure. A 'dispersion' model based on channeling is presented. The results from the sorbing tracers indicate that there is substantial diffusion into and sorption in the rock matrix. Sorption on the surface of the fissure also accounts for a part of the retardation effect of the sorbing species. A model which includes the mechanisms of channeling, surface sorption matrix diffusion and matrix sorption is presented. The experimental breakthrough curves can be fitted fairly well by this model by use of independently obtained data on diffusivities and matrix sorption. (author)

Tracer Movement in a Single Fissure in Granitic Rock: Some Experimental Results and Their Interpretation

Science.gov (United States)

Neretnieks, Ivars; Eriksen, Tryggve; TäHtinen, PäIvi

1982-08-01

Radionuclide migration was studied in a natural fissure in a granite core. The fissure was oriented parallel to the axis in a cylindrical core 30 cm long and 20 cm in diameter. The traced solution was injected at one end of the core and collected at the other. Breakthrough curves were obtained for the nonsorbing tracers, tritiated water, and a large-molecular-weight lignosulphonate molecule and for the sorbing tracers, cesium and strontium. From the breakthrough curves for the nonsorbing tracers it could be concluded that channeling occurs in the single fissure. A `dispersion' model based on channeling is presented. The results from the sorbing tracers indicate that there is substantial diffusion into and sorption in the rock matrix. Sorption on the surface of the fissure also accounts for a part of the retardation effect of the sorbing species. A model which includes the mechanisms of channeling, surface sorption, matrix diffusion, and matrix sorption is presented. The experimental breakthrough curves can be fitted fairly well by this model by use of independently obtained data on diffusivities and matrix sorption.

Comparative study of resin sealant and resin modified glass ionomer as pit and fissure sealant

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Shirin Malek

2017-02-01

Full Text Available The purpose of the present study was to compare the marginal integrity of resin modified glass ionomer cement with that of resin sealant, in vitro. Forty artificial pit and fissure cavities were prepared in occlusal surface of extracted premolar teeth by using ¼ round carbide bur. Cavities were condensed with artificial organic debris followed by cleaning with prophylaxis pumice brush and paste and then separated into two treatment groups. In Group A, 15 fissure cavities were sealed by resin sealant and in Group B, 15 fissure cavities were sealed by resin modified glass ionomer sealant. These specimens were subjected to thermo-cycling followed by dye penetration test. The remaining 5 cavities from each group were analyzed for debris score by the SEM. The results of the microleakage test showed that the efficacy of preventing microleakage of samples sealed by resin modified glass ionomer sealant was higher than the samples sealed by resin sealant. However, no significant differences were found. It can be concluded that use of resin modified glass ionomer sealant is a good alternative for sealing pits and fissures.

Skin hydration of the heel with fissure in patients with diabetes: a cross-sectional observational study

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Oe M

2018-06-01

Full Text Available Makoto Oe,1 Kimie Takehara,2 Hiroshi Noguchi,3 Yumiko Ohashi,4 Mayu Fukuda,1 Takashi Kadowaki,5 Hiromi Sanada1,6 1Global Nursing Research Center, 2Department of Advanced Nursing Technology, 3Department of Life Support Technology (Molten, Graduate School of Medicine, The University of Tokyo, 4Department of Nursing, The University of Tokyo Hospital, 5Department of Diabetes and Metabolic Diseases, 6Department of Gerontological Nursing/Wound Care Management, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan Purpose: Foot fissure should be prevented in patients with diabetes due to the likelihood of subsequent diabetic ulcer. The purpose of this study was to investigate a cutoff point for skin hydration with fissure and the factors associated with low skin hydration in patients with diabetes. Subjects and methods: Subjects were patients with diabetes who visited the diabetic foot clinic and were evaluated for skin hydration on the heel between April 2008 and March 2015. Information about fissure, skin hydration, age, sex, autonomic neuropathy, angiopathy, and tinea pedis were collected from the medical charts. Skin hydration on the heel was measured using a moisture checker. Skin hydration was compared between heels with and without fissure, and a cutoff for skin hydration with fissure was determined using receiver operating characteristic analysis. Based on the determined cutoff, factors associated with lower skin hydration were analyzed using logistic regression analysis. Results: Participants comprised 693 patients. Mean±SD age was 66.8±10.8 years, and 57.0% of subjects were male. The frequency of fissures on the heels was 10.4%. Area under the receiver operating characteristic curve for skin hydration in the presence of fissure was 0.717. Twenty percent was selected as the cutoff point, offering sensitivity of 0.478 and specificity of 0.819. Logistic regression analysis showed correlations between three factors (male sex, tinea

A 1-year clinical evaluation of fissure sealants on permanent first molars

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Nupur Ninawe

2012-01-01

Full Text Available Objective : To evaluate and compare the retention, marginal discoloration, surface texture and anatomical form of pit and fissure sealants. Materials and Methods : Thirty children between the ages of 6 and 10 years, who were attending the school health program regularly, had participated in the study. A split-mouth design was used in which the two fissure sealants (Helioseal-F and Glass ionomer Fuji VII were randomly placed in 60 matched contralateral pairs of permanent molar teeth. Sealants were rated by a single trained and calibrated examiner using mouth mirrors and probes following the US Public Health Service criteria. The sealants were evaluated at 3 months, 6 months and 1 year intervals. Results : The data obtained for retention, marginal discoloration, surface texture and anatomical form of pit and fissure sealants were tabulated and compared statistically using the Chi-square test of significance. Conclusion : The Helioseal-F sealant was better than the Glass ionomer Fuji VII sealant with respect to retention, anatomical form and surface texture. Both the materials showed similar results with respect to marginal discoloration.

Utility of Indocyanine Green Video Angiography for Sylvian Fissure Dissection in Subarachnoid Hemorrhage Patients - Sylvian ICG Technique.

Science.gov (United States)

Toi, Hiroyuki; Matsushita, Nobuhisa; Ogawa, Yukari; Kinoshita, Keita; Satoh, Kohei; Takai, Hiroki; Hirai, Satoshi; Hara, Keijiro; Matsubara, Shunji; Uno, Masaaki

2018-02-15

Indocyanine green (ICG) emits fluorescence in the far-red domain under light excitation. ICG video angiography (ICG-VA) has been established as a useful method to evaluate blood flow in the operative field. We report the usefulness of ICG-VA for Sylvian fissure dissection in patients with subarachnoid hemorrhage (SAH). Subjects comprised 7 patients who underwent ICG-VA before opening the Sylvian fissure during neck clipping for ruptured cerebral aneurysm. We observed contrasted Sylvian veins before opening the Sylvian fissure using surgical microscopes. This procedure was termed "Sylvian ICG". We observed ICG fluorescence quickly in all cases. Sylvian veins that appeared unclear in the standard microscopic operative field covered with subarachnoid hemorrhage were extremely clearly depicted. These Sylvian ICG findings were helpful in identifying entry points and the dissecting course of the Sylvian fissure. At the time of clipping, no residual fluorescence from Sylvian ICG was present, and aneurysm clipping was not impeded. Sylvian ICG for SAH patients is a novel technique to facilitate dissection of the Sylvian fissure. We believe that this technique will contribute to improved safety of clipping surgery for ruptured aneurysms.

Impact de la preparation des anodes crues et des conditions de cuisson sur la fissuration dans des anodes denses

Science.gov (United States)

Amrani, Salah

La fabrication de l'aluminium est realisee dans une cellule d'electrolyse, et cette operation utilise des anodes en carbone. L'evaluation de la qualite de ces anodes reste indispensable avant leur utilisation. La presence des fissures dans les anodes provoque une perturbation du procede l'electrolyse et une diminution de sa performance. Ce projet a ete entrepris pour determiner l'impact des differents parametres de procedes de fabrication des anodes sur la fissuration des anodes denses. Ces parametres incluent ceux de la fabrication des anodes crues, des proprietes des matieres premieres et de la cuisson. Une recherche bibliographique a ete effectuee sur tous les aspects de la fissuration des anodes en carbone pour compiler les travaux anterieurs. Une methodologie detaillee a ete mise au point pour faciliter le deroulement des travaux et atteindre les objectifs vises. La majorite de ce document est reservee pour la discussion des resultats obtenus au laboratoire de l'UQAC et au niveau industriel. Concernant les etudes realisees a l'UQAC, une partie des travaux experimentaux est reservee a la recherche des differents mecanismes de fissuration dans les anodes denses utilisees dans l'industrie d'aluminium. L'approche etait d'abord basee sur la caracterisation qualitative du mecanisme de la fissuration en surface et en profondeur. Puis, une caracterisation quantitative a ete realisee pour la determination de la distribution de la largeur de la fissure sur toute sa longueur, ainsi que le pourcentage de sa surface par rapport a la surface totale de l'echantillon. Cette etude a ete realisee par le biais de la technique d'analyse d'image utilisee pour caracteriser la fissuration d'un echantillon d'anode cuite. L'analyse surfacique et en profondeur de cet echantillon a permis de voir clairement la formation des fissures sur une grande partie de la surface analysee. L'autre partie des travaux est basee sur la caracterisation des defauts dans des echantillons d'anodes crues

Can earthquake fissures predispose hillslopes to landslides? - Evidence from Central and East Asia

Science.gov (United States)

Sidle, Roy C.; Gomi, Takashi; Rajapbaev, Muslim; Chyngozhoev, Nurstan

2017-04-01

Factors affecting earthquake-initiated landslides include earthquake magnitude, focal depth, and seismic wave propagation and attenuation. In contrast to rainfall-initiated landslides, earthquake-induced landslides often occur on convex slopes and near ridgelines. Here we present evidence from Fergana Basin, Kyrgyzstan and Kumamoto, Japan on how fissures developed during earthquakes may promote subsequent initiation of rainfall-triggered landslides. More than 1800 recent major landslides in hilly terrain and soft sediments of the Fergana Basin have been largely attributed to accumulation of heavy rainfall and snowmelt. While no large earthquakes have occurred in the Fergana Basin, smaller earthquakes have generated fissures near ridgelines and on convex slopes. The connection of fissures, developed years or decades before slope failure, with preferential transport of rainwater and runoff into the soil has not been previously investigated. Fissures have been observed to expand with time, particularly during subsequent minor earthquakes, further promoting preferential infiltration. Because the soil mantle does not have large contrasts in permeability that would define a slip plane for landslides, it appears that the position and depth of these fissures may control the location and depth of failures. Zones in the soil where surficial inputs of water are preferentially transported, augment natural subsurface accumulation of antecedent rainfall. Many landslides in the eastern Fergana Basin occur after several months of accumulated precipitation and groundwater has been observed emerging on critical hillside locations (near ridgelines and on convex slopes) prior to slope failure. During the 2016 Kumamoto Earthquake (M 7.3), many landslides were triggered in forest and grassland hillslopes near Mount Aso. All of these earthquakes were shallow (focal depths about 10 km), causing high shaking intensity and ground rupturing. Because soils were relatively dry during these

The effect of different enamel surface treatments on microleakage of fissure sealants

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Asli Topaloglu-Ak

2013-11-01

Full Text Available Objective. The aim of this study was to evaluate the effects of different techniques of surface treatment on the microleakage of fissure sealants in permanent molar teeth in vitro. Materials and methods. 96 extracted impacted human third molars were randomly divided into 8 surface treatment groups (n=12/group as 1. Er: YAG laser; (Fidelis II, Fotona, Ljubljana, Slovenia (125 mj, 20Hz. 2. Er: YAG laser + 37% H3PO4 (15s; 3. ER: AG laser + 37% H3PO4+Prime&Bond NT; 4. Er: YAG laser + G Bond; 5. Er: YAG laser + Prime&Bond NT; 6. 37% H3PO4; 7. 37% H3PO4 + Prime &Bond NT; 8. G Bond. Sealant material (Clinpro, 3M ESPE, Seefeld, Germany, was applied into the fissures and light-cured for 20s with LED (Bluephase C5, Ivoclar-Vivadent, Schaan, Liechtenstein. Specimens were subjected to thermocycling (1000×, 5-55°C, dwell time: 15s and immersed in 0.5% basic fuchsin solution for 24h at 37°C. The samples were sectioned and scored on a 3 point rating scale using a light microscope with a magnification of ×20. One-way analysis of variance was used to analyze data. Multiple comparisons were analyzed using Bonferroni test (p=0.05. Results. Er:YAG laser showed the highest microleakage scores whereas Er YAG laser + 37% H3PO4 showed the lowest. Although 37% H3PO4 group showed higher scores than Er:YAG laser + 37% H3PO4, the difference was not statistically significant. Conclusion. Etching fissures with phosphoric acid is sufficient prior to fissure sealant application.

The Lobe Fissure Tracking by the Modified Ant Colony Optimization Framework in CT Images

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Chii-Jen Chen

2014-11-01

Full Text Available Chest computed tomography (CT is the most commonly used technique for the inspection of lung lesions. However, the lobe fissures in lung CT is still difficult to observe owing to its imaging structure. Therefore, in this paper, we aimed to develop an efficient tracking framework to extract the lobe fissures by the proposed modified ant colony optimization (ACO algorithm. We used the method of increasing the consistency of pheromone on lobe fissure to improve the accuracy of path tracking. In order to validate the proposed system, we had tested our method in a database from 15 lung patients. In the experiment, the quantitative assessment shows that the proposed ACO method achieved the average F-measures of 80.9% and 82.84% in left and right lungs, respectively. The experiments indicate our method results more satisfied performance, and can help investigators detect lung lesion for further examination.

Natural Treatments for Fissure in Ano Used by Traditional Persian Scholars, Razi (Rhazes) and Ibn Sina (Avicenna).

Science.gov (United States)

Derakhshan, Ali Reza

2016-06-08

Most cases of chronic fissure do not respond to medical treatment. Razi and Ibn Sina were 2 of the best-known scientists of ancient Persia. The purpose of this study was to find out new scientific evidence in modern medicine about their recommendations, in order to find certain clues to conduct useful researches in the future. First, treatments of anal fissure mentioned by Razi and Ibn Sina were reviewed. Then, literature search was made in electronic databases including PubMed, Scopus, and Google Scholar. Management of anal fissure according to Razi's and Ibn Sina's practices is done based on 3 interventions: lifestyle modifications, drug treatments, and manual procedures. Almost all remedies suggested by Razi and Ibn Sina have shown their effects on fissure in ano via several mechanisms of action in many in vitro and in vivo studies; Still there is lack of human studies on the subject. © The Author(s) 2016.

Comparing the etiology and treatment of skin fissure in traditional and conventional medicine; a brief review

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A. Jedkareh

2016-01-01

Full Text Available Dry skin is a common problem which affects wound healing, severity of other skin diseases and quality of life of people. One of its undesirable effects is fissure that is a cutaneous condition in which there is a linear loss of epidermis and dermis with sharply defined, nearly vertical walls. In the present study, we have investigated the etiology of the disease and its treatments in conventional medicine and Iranian Traditional Medicine (ITM. Two traditional medicine references, current scientific data bases and medicinal texts were explored with the selected keywords such as "sheqaq-e-poosti", "skin fissure" and "dry skin" to find the etiology and treatment of skin fissure. From the view point of both conventional medicine and ITM, dry skin is the cause of skin fissure and some causes of dry skin are similar. In conventional medicine, moisturizers are mainly used for treatment of dry skin; while in ITM some herbs, oils and other natural remedies have been used. A topical dosage form which was called "qeirooti", a mixture of wax and oil, was used to treat skin fissure in ITM. It comprised of oily ingredients that acted as occlusives and also some herbal components that directly improved dry skin (similar to moisturizers. Components efficacy of traditional dosage forms for treatment of dry skin lead us to study about formulation of “qeirooti” for treatment of dry skin.

Water Stream in Bidet Toilet Commode as a Cause of Anterior Anal Fissure: A Case-Control Study

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Pankaj Garg

2017-03-01

Full Text Available Background Water used as a single sharp stream in toilet commode for post defecation cleansing is a common practice in several countries across the globe including India. Repeated hitting of the anus by water stream could potentially cause injury to the anal canal epithelium and lead to development of fissure-in-ano. As the water stream is emanating from the backside of the toilet commode, the possible injury, if any, would be on the anterior anal canal. Objectives The present study aimed at determining whether water stream usage in toilet commodes increased the incidence of anterior fissure-in-ano; this was determined by the incidence of anterior fissure-in-ano the study and control groups. Methods All consecutive fissure-in-ano patients referring to a colorectal clinic from February 2012 to 2015 were included in the study. The patients were classified as a study group (who were using water stream for cleansing purposes in toilet commodes and a control group (patients who were not using water stream. The characteristics and location (position of the fissure-in-ano was noted. Results In this study, 165 patients were prospectively enrolled. Male/female ratio was 96/69, and the mean age was 36.3 ± 11.2 years. The anterior fissure-in-ano in the study group was 55.9% (47/84, while it was 17.3 % (14/81 in the control group (P < 0.0001, odds ratio: 6.08, 95% CI: 2.96 - 12.47]. Conclusions Water used as a single sharp stream to cleanse after defecation in toilet commodes is hazardous and should be avoided.

Endobronchial valves in severe emphysematous patients: CT evaluation of lung fissures completeness, treatment radiological response and quantitative emphysema analysis

Energy Technology Data Exchange (ETDEWEB)

Koenigkam-Santos, Marcel, E-mail: marcelk46@yahoo.com.br, E-mail: marcelk46@usp.b [Universidade de Sao Paulo (HCFMRP/USP), Ribeirao Preto, SP (Brazil). Hospital das Clinicas da Faculdade de Medicina; Paula, Wagner Diniz de [University of Brasilia (UnB), DF (Brazil). Brasilia University Hospital; Gompelmann, Daniela [University of Heidelberg (Germany). Department of Pneumology and Respiratory Medicine of the Chest Clinic (Thoraxklinik); Kauczor, Hans-Ulrich [University of Heidelberg (Germany). Department of Diagnostic and Interventional Radiology; Heussel, Claus Peter; Puderbach, Michael [University of Heidelberg (Germany). Department of Diagnostic and Interventional Radiology with Nuclear Medicine of the Chest Clinic (Thoraxklinik)

2013-01-15

Objective: To evaluate lung fissures completeness, post-treatment radiological response and quantitative CT analysis (QCTA) in a population of severe emphysematous patients submitted to endobronchial valves (EBV) implantation. Materials and Methods: Multi-detectors CT exams of 29 patients were studied, using thin-section low dose protocol without contrast. Two radiologists retrospectively reviewed all images in consensus; fissures completeness was estimated in 5% increments and post-EBV radiological response (target lobe atelectasis/volume loss) was evaluated. QCTA was performed in pre and post-treatment scans using a fully automated software. Results: CT response was present in 16/29 patients. In the negative CT response group, all 13 patients presented incomplete fissures, and mean oblique fissures completeness was 72.8%, against 88.3% in the other group. QCTA most significant results showed a reduced post-treatment total lung volume (LV) (mean 542 ml), reduced EBV-submitted LV (700 ml) and reduced emphysema volume (331.4 ml) in the positive response group, which also showed improved functional tests. Conclusion: EBV benefit is most likely in patients who have complete interlobar fissures and develop lobar atelectasis. In patients with no radiological response we observed a higher prevalence of incomplete fissures and a greater degree of incompleteness. The fully automated QCTA detected the post-treatment alterations, especially in the treated lung analysis. (author)

Newborn with Prenatally Diagnosed Choroidal Fissure Cyst and Panhypopituitarism and Review of the Literature

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Ritu Chitkara

2011-12-01

Full Text Available Little has been reported on fetal diagnosis of choroidal fissure cysts and prediction of the clinical complications that can result. We describe the case of a near-term male infant with prenatally diagnosed choroidal fissure cyst and bilateral clubfeet. His prolonged course in the neonatal intensive care nursery was marked by severe panhypopituitarism, late-onset diabetes insipidus, placement of a cystoperitoneal shunt, and episodes of sepsis. Postnatal genetic evaluation also revealed an interstitial deletion involving most of band 10q26.12 and the proximal half of band 10q26.13. The patient had multiple readmissions for medical and surgical indications and died at 6 months of age. This case represents the severe end of the spectrum of medical complications for children with choroidal fissure cysts. It highlights not only the importance of comprehensive evaluation and multidisciplinary management and counseling in such cases, but also the need for heightened vigilance in these patients.

Deformation at longyao ground fissure and its surroundings, north China plain, revealed by ALOS PALSAR PS-InSAR

Science.gov (United States)

Yang, Chengsheng; Lu, Zhong; Zhang, Qin; Zhao, Chaoying; Peng, Jianbing; Ji, Lingyun

2018-05-01

The Longyao ground fissure (LGF) is the longest and most active among more than 1000 ground fissures on the North China Plain. There have been many studies on the formation mechanism of the LGF, due to its scientific importance and its potential for damage to the environment. These studies have been based on both regional tectonic analysis and numerical simulations. In order to provide a better understanding of the formation mechanism, the deformation of the crack and its surrounding environment should be taken into consideration. In this paper, PS-InSAR technology was employed to assess the ground deformation of LGF and its surrounding area, using L-band ALOS-1 PALSAR images from 2007 to 2011. The characteristics of ground deformation, relationships between fissure activity and surrounding faults and groundwater exploitation were analyzed. This study shows that the north side of Longyao fault (LF) is uplifting while the south side is subsiding. This provides the tectonic conditions responsible for the activity of the ground fissure. Local groundwater exploitation also plays an important role in the development of ground fissures. InSAR observations were modeled to infer the loading depth (-2.8 km) and the slip rate (31.1 mm/yr) of LF.

Analysis of some laboratory tracer runs in natural fissures

International Nuclear Information System (INIS)

Moreno, L.; Neretnieks, I.

1984-01-01

Tracer tests in natural fissures performed in the laboratory are analysed by means of fitting two different models. In the experiments, sorbing and non-sorbing tracers were injected into a natural fissure running parallel to the axis of a drill core. The models take into account advection, diffusion into the rock matrix, sorption onto the rock surface and dispersion. For the last mechanism, one of the models considers hydrodynamic dispersion while the other model assumes channeling dispersion. The models take into account time delays in the inlet and outlet channels. The dispersion characteristics and water residence time were determined from the experiments with non-sorbing tracers. Surface and volume sorption coefficients and data on diffusion into the rock matrix were determined for the sorbing tracers. The results are compared with values independently determined in the laboratory. Good agreement was obtained using either model. When these models are used for prediction of tracer transport over larger distances, the results will depend on the model. The model with channeling dispersion will show a greater dispersion than the model with hydrodynamic dispersion. (author)

Preconsolidation of Søvind Marl - a highly fissured Eocene clay

DEFF Research Database (Denmark)

Grønbech, Gitte Lyng; Ibsen, Lars Bo; Nielsen, Benjaminn Nordahl

2015-01-01

Determination of the preconsolidation stresses is a key tool in geotechnical engineering used to evaluate and estimate the behavior of soils. However, it has been proven difficult to accurately estimate the preconsolidation in highly fissured overconsolidated clays, due to the effect of the fissu...

Clinical effectiveness and cost-effectiveness of fissure sealants in children and adolescents with a high caries risk

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Neusser, Silke

2014-10-01

Full Text Available [english] In Germany, the application of resin-based pits and fissures sealants on the occlusal surfaces of permanent molars is part of individual prophylaxis for children and adolescents between six and 18 years. The individual prophylaxis is covered by the Statutory Health Insurance since 1993.The report addresses questions on medical effectiveness, cost-effectiveness, as well as ethical, social, and legal implications of pit and fissure sealants in preventing dental caries for children and adolescents at high caries risk. The results of the studies indicate a protective effect of pit and fissure sealants, particularly for children and adolescents at high caries risk. Additionally, the economic evaluation suggests a tendency for cost savings in this group. Nevertheless, a general expansion of the intervention cannot be recommended. All studies show a risk of bias in favour of pit and fissure sealing and a limited transferability to the German health care system. Studies included in the economic evaluation revealed methodological flaws. Both the economic models and primary studies do not provide reliable results.

King's Bowl Pit Crater, Lava Field and Eruptive Fissure, Idaho - A Multipurpose Volcanic Planetary Analog

Science.gov (United States)

Hughes, S. S.; Garry, B.; Kobs-Nawotniak, S. E.; Sears, D. W. G.; Borg, C.; Elphic, R. C.; Haberle, C. W.; Kobayashi, L.; Lim, D. S. S.; Sears, H.; Skok, J. R.; Heldmann, J. L.

2014-12-01

King's Bowl (KB) and its associated eruptive fissure and lava field on the eastern Snake River Plain, is being investigated by the NASA SSERVI FINESSE (Field Investigations to Enable Solar System Science and Exploration) team as a planetary analog to similar pits on the Moon, Mars and Vesta. The 2,220 ± 100 BP basaltic eruption in Craters of the Moon National Monument and Preserve represents early stages of low shield growth, which was aborted when magma supply was cut off. Compared to mature shields, KB is miniscule, with ~0.02 km3 of lava over ~3 km2, yet the ~6 km long series of fissures, cracks and pits are well-preserved for analog studies of volcanic processes. The termination of eruption was likely related to proximity of the 2,270 ± 50 BP eruption of the much larger Wapi lava field (~5.5 km3 over 325 km2 area) on the same rift. Our investigation extends early work by R. Greeley and colleagues, focusing on imagery, compositional variations, ejecta distribution, dGPS profiles and LiDAR scans of features related to: (1) fissure eruptions - spatter ramparts, cones, feeder dikes, extension cracks; (2) lava lake formation - surface morphology, squeeze-ups, slab pahoehoe lava mounds, lava drain-back, flow lobe overlaps; and (3) phreatic steam blasts - explosion pits, ejecta blankets of ash and blocks. Preliminary results indicate multiple fissure eruptions and growth of a basin-filled lava lake up to ~ 10 m thick with outflow sheet lava flows. Remnant mounds of original lake crust reveal an early high lava lake level, which subsided as much as 5 m as the molten interior drained back into the fissure system. Rapid loss of magma supply led to the collapse of fissure walls allowing groundwater influx that triggered multiple steam blasts along at least 500 m. Early blasts occurred while lake magma pressure was still high enough to produce squeeze-ups when penetrated by ejecta blocks. The King's Bowl pit crater exemplifies processes of a small, but highly energetic

Novel QTLs affecting rice kernel fissure resistance discovered in the cultivar ‘Saber’ augment those from ‘Cybonnet’

Science.gov (United States)

Kernel fissures in rice (Oryza sativa L.) caused by pre- or post-harvest stresses are the leading cause of breakage among milled rice. Such breakage causes economic losses for producers, millers, and marketers. Five QTLs for kernel fissure resistance (FR) were identified among a set of 275 RILs de...

Comparison of botox and lateral internal sphincterotomy treatment outcomes in chronic anal fissures

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Tolga Dinç

2014-03-01

Full Text Available Objective: Both botox and lateral internal sfinkterotomi are treatment technics used in chronic anal fissure; provide the relaxation of anal sphincter and as a result of this, healing occurs. Aim of this study is to compare efficacy of botox and LIS treatment in chronic anal fissure and discussing with the literature. Methods: 60 of 66 patients who has chronic anal fissure, that we reached, treated but not healed with medical therapy, appealed to the Dr. Sami Ulus Hospital included the study. Gender, age, fissure localization, complaints (pain, bleeding, itching, constipation, complaint length, recurrences after treatment, continence conditions and complications of patients were registered. Results: Sixty patients were enrolled the study. Of the 60 patients; 38(63.3% were male and 22 (27.7% were female. Mean age of all patients was 35.93 ± 11.45 (21 -60. Pain was the common complaint of the all patients. 10 (32.3% recurrence were detected in botox treatment group (Group-I, only 1 (3.4% recurrence was in LIS group (Group-II. There was no complication as an incontinence in group-I but 3 cases with incontinence (10.39% were obtained in group-II. In the evaluation of these 3 cases by Cleveland Clinic Continence Scoring System, 2 cases classified as gas incontinence and 1 case as moderate fecal incontinence. Conclusion: Although botulinum toxin injection seen as an alternative treatment method with low complication rates such as incontinence, high recurrence is an important shortcoming of this technic. LIS performed by experienced surgeons remained the most popular treatment modality with low complication rates and great deal of healing success.

Landslide Fissure Inference Assessment by ANFIS and Logistic Regression Using UAS-Based Photogrammetry

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Ozgun Akcay

2015-10-01

Full Text Available Unmanned Aerial Systems (UAS are now capable of gathering high-resolution data, therefore, landslides can be explored in detail at larger scales. In this research, 132 aerial photographs were captured, and 85,456 features were detected and matched automatically using UAS photogrammetry. The root mean square (RMS values of the image coordinates of the Ground Control Points (GPCs varied from 0.521 to 2.293 pixels, whereas maximum RMS values of automatically matched features was calculated as 2.921 pixels. Using the 3D point cloud, which was acquired by aerial photogrammetry, the raster datasets of the aspect, slope, and maximally stable extremal regions (MSER detecting visual uniformity, were defined as three variables, in order to reason fissure structures on the landslide surface. In this research, an Adaptive Neuro Fuzzy Inference System (ANFIS and a Logistic Regression (LR were implemented using training datasets to infer fissure data appropriately. The accuracy of the predictive models was evaluated by drawing receiver operating characteristic (ROC curves and by calculating the area under the ROC curve (AUC. The experiments exposed that high-resolution imagery is an indispensable data source to model and validate landslide fissures appropriately.

The movement of solutes through aqueous fissures in micro-porous rock during borehole experiments

International Nuclear Information System (INIS)

Glueckauf, E.

1981-02-01

When a tracer is injected for a short period into a solution flowing through a fissure in micro-porous rock, that tracer is not only carried along by the aqueous stream, but its local concentration is also markedly affected by hydro-dynamic dispersion and by sideway diffusion and adsorption in the micro-porous rock. The process has been simulated by computer calculations and these have made it possible to obtain from the concentration-time curves observed in borehole experiments an assessment of the physical parameters involving the water velocity and the hydro-dynamic dispersion in the fissure, and the diffusion and adsorption in the micro-porous rock. With these parameters it was then possible to recalculate quantitatively the local concentration-time history. However, in actual borehole experiments, the velocity of the water stream in the fissure is not known, and numerous side effects can distort the shape of the observed tracer curves. In order to test the theoretical interpretation more thoroughly, it is therefore proposed to carry out a laboratory experiment which simulates the borehole test under strictly defined conditions. (author)

Fissuring-chemical damaging on transfers in concrete

International Nuclear Information System (INIS)

Tognazzi, C.

1998-01-01

Concrete is a material often use in the nuclear wastes disposal. The safety analysis of a long time wastes disposal with concrete requires to verify the concrete behaviour in water. As concretes generally have cracks, it is necessary to study the crack propagation influence on chemical degradation. In this paper, the author presents diffusion tests on fissured and/or chemical aged cement. The chemical degradation of the material leads to a supplementary porosity by the hydrates decalcification and increases its diffusivity. The cracking impact is less important and can be experimentally concealed. (A.L.B.)

Modeling and numerical study of transfers in fissured environments; Modelisation et etude numerique des transferts en milieux fissures

Energy Technology Data Exchange (ETDEWEB)

Granet, S.

2000-01-28

Oil recovery from fractured reservoirs plays a very important role in the petroleum industry. Some of the world most productive oil fields are located in naturally fractured reservoirs. Modelling flow in such a fracture network is a very complex problem. This is conventionally done using a specific idealized model. This model is based on the Warren and Root representation and on a dual porosity, dual permeability approach. A simplified formulation of matrix-fracture fluid transfers uses a pseudo-steady-state transfer equation involving a constant exchange coefficient. Such a choice is one of the main difficulties of this approach. To get a better understanding of the simplifications involved in the dual porosity approach a reference model must be available. To obtain such a fine description, we have developed a new methodology. This technique called 'the fissure element methodology' is based on a specific gridding of the fractured medium. The fissure network is gridded with linear elements coupled with an unstructured triangular grid of matrix. An appropriate finite volume scheme has been developed to provide a good description of the flow. The numerical development of is precisely described. A simulator has been developed using this method. Several simulations have been realised. Comparisons have been done with different dual-porosity dual-permeability models. A reflexion concerning the choice of the exchange coefficient used in the dual porosity model is then proposed. This new tool has permit to have a better understanding of the production mechanisms of a complex fractured reservoir. (author)

Effects of menthol essence and breast milk on the improvement of nipple fissures in breastfeeding women

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Sedigheh Amir Ali Akbari

2014-01-01

Full Text Available Background: Nipple fissure is a common disorder during breastfeeding. With high prevalence of nipple fissures and its impacts on breastfeeding, as well as the existence of evidence in favor of the application of peppermint as an antiinflammatory and antiinfection herb, the purpose of this study is to determine the effect of Menthol essence on improving nipple fissures in the primiparous breastfeeding women. Materials and Methods: This study was conducted using a clinical trial method. Samples were divided randomly into two groups of 55 women. The women in the peppermint group applied four drops of Menthol essence on their nipple and areola after each feeding. The control group applied four drops of their own milk on the nipple and areola after each feeding. Then, the two groups were studied on days 10 and 14 postpartum. For intensity of pain, the visual analog scale (0-10 cm and to measure the severity of damage, Amir scale (1-10 cm were applied and the existence or lack of nipple discharge was also recorded. The data were analyzed using SPSS 17 software. Results: The mean intensity of pain and nipple fissure before treatment (8.55 ± 1.74 and day 10 after delivery (4.26 ± 1.57 and before treatment and day 14 after delivery in the case group (1.32 ± 1.02 had a significant difference (P < 0.001. Nipple discharge between the two groups, before treatment (%75.2 and day 10 after delivery (%31.6 and before treatment and day 14 after delivery (%15.7, the case group had a significant difference (P < 0.001. Conclusion: Menthol essence can improve nipple fissures in the primiparous breastfeeding women.

Short linear shadows connecting pulmonary segmental arteries to oblique fissures in volumetric thin-section CT images: comparing CT, micro-CT and histopathology

International Nuclear Information System (INIS)

Guan, Chun-Shuang; Ma, Da-Qing; Chen, Jiang-Hong; Chen, Bu-Dong; Cui, Dun; Zhang, Yan-Song; Liu, Wei-Hua

2016-01-01

To retrospectively evaluate short linear shadows connecting pulmonary segmental arteries to oblique fissures in thin-section CT images and determine their anatomical basis. CT scanning was performed on 108 patients and 11 lung specimens with no lung diseases around the oblique fissures or hilar. Two radiologists evaluated the imaging. The parameters included length, thickness of short linear shadows, pulmonary segmental artery variations, and traction interlobar fissures, etc. The short linear shadows were not related to sex, age, or smoking history. The lengths of the short linear shadows were generally within 10 mm. The thicknesses of the short linear shadows ranged from 1 to 2 mm. Of the patients, 26.9 % showed pulmonary segmental artery variations; 66.7 % of short linear shadows pulled oblique fissures. In three-dimensional images, the short linear shadows appeared as arc planes, with one side edge connected to the oblique fissure, one side edge connected to a pulmonary segmental artery. On the tissue slices, the short linear shadow exhibited a band structure composed of connective tissues, small blood vessels, and small lymphatic vessels. Short linear shadows are a type of normal intrapulmonary membranes and can maintain the integrity of the oblique fissures and hilar structure. (orig.)

Application of passive type radon detectors to find fissures in banks caused by the southern Hyogo prefectural earthquake in Japan

International Nuclear Information System (INIS)

Saegusa, J.; Yamasaki, K.; Tsujimoto, T.; Morishima, H.; Shimo, M.; Murakami, A.; Hasegawa, T.

1996-01-01

Innumerable fissures were formed widely in Hanshin area in Japan by the former southern Hyogo prefectural earthquake occurred on Jan.17, 1995. In this study, as a preliminary investigation, we applied passive type radon detector Pico-Rad (U.S. Packard Instrument Co. Ltd.) with hemispheric plastic cover over them around the fissure along on the bank of two reservoirs to examine whether there is possibility to find fissures using the characteristics of 222 Rn migration. One of the reservoir, Taniyamakami-ike, is located at the north of the Awaji-shima island at a distance of about 4 km from the seismic center of this earthquake. On the whole, 222 Rn exhalation rates were high on a line of 2 m below the edge of the bank and got lower in proportion to the distance from this line. Those top of the bank had middle values among the lines. The mean 222 Rn exhalation rate was 4.7 mBq m -2 s -1 , and in these data we found some singularly high 222 Rn points. The other reservoir named Hosho-ike is located at northwestern Nagaokakyo city of Kyoto prefecture and the Komyoji active faulting runs from north to south parallel with the bank about 120 m to the west. In this bank, a fissure about 50 m in length and 0.1 m in width was taken shape. 222 Rn exhalation rates were relatively high on the top of the bank compared with on the slope of the bank. The mean 222 Rn exhalation rate of 5 points which were measured on the fissure was 16 mBq m -2 s -1 , and that which were measured on about 1 m to the east from the fissure was 4.9 mBq m -2 s -1 and in case about 1 m to the west was 4.2 mBq m -2 s -1 . From these results we concluded that there is a possibility to find fissures inside the bank using the characteristics of 222 Rn migration. Our future objective is to find fissures inside banks non-destructively. (author)

Sealing effectiveness of fissure sealant bonded with universal adhesive systems on saliva-contaminated and noncontaminated enamel.

Science.gov (United States)

Memarpour, Mahtab; Shafiei, Fereshteh; Zarean, Mehran; Razmjoei, Faranak

2018-01-01

The effectiveness of sealants is dependent upon their adhesion to enamel surface. The aim of the study was to evaluate the sealing ability of a pit and fissure sealant used with a universal adhesive (etch-and-rinse vs. self-etch modes) when the site is contaminated with saliva. Adhesive properties were evaluated as microleakage and scanning electron microscopic (SEM) characteristics. A total of 72 mandibular third molars were randomly divided into 6 groups (n=12). Occlusal pits and fissures were sealed with an unfilled resin fissure sealant (FS) material with or without saliva contamination. The groups included: 1) phosphoric acid etching + FS (control), 2) phosphoric acid etching + Scotchbond Universal (etch-and-rinse) + FS, 3) phosphoric acid etching + saliva + Scotchbond Universal (etch-and-rinse) + FS, 4) Scotchbond Universal (self-etching) + FS,5) Scotchbond Universal (self-etching) + saliva + FS, and 6) Scotchbond Universal (self-etching) + saliva + Scotchbond Universal + FS. After thermocycling, the teeth were placed in 0.5% fuchsin, sectioned, and evaluated by digital microscopy. Two samples from each group were also observed by SEM. The data were analyzed with Kruskal-Wallis and Mann-Whitney tests for a significance of p universal adhesive in etch-and-rinse or self-etch modes was similar to that of conventional acid etching. Saliva contamination had a negative effect on sealant adhesion to pretreated enamel. Key words: Pit and fissure sealant, Universal adhesive, Saliva.

The differences of saliva pH before and after application of Bis-GMA resin based-pit and fissure sealant

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Ayub Irmadani Anwar

2016-06-01

Full Text Available Pit and fissure sealant applications is one way to prevent caries. One of the effective ingredient as a pit and fissure sealant is a Bis-GMA resin. One of the active components  of  Bis-GMA  resin  is  sodium  fluoride,  which is capable  of releasing fluoride ions to the tooth surface and able to improve the repair and remineralization process through the replacement  of  calcium and phosphate ions found in saliva to increase the pH of saliva. This study was to determine the effect of pit and fissure sealant applications made from Bis-GMA resin to pH of saliva in children aged 6-12 years. The study design is pre and post test with control group design. Saliva samples were derived from 15 pediatric patients has met the criteria. The pH of saliva were taken before and after the application of pit and fissure sealant made from Bis-GMA and measured with pH meter. This study used a non-parametric test, the Wilcoxon Signed Rank test. The results of this study are also supported by the results of statistical tests showed p-: 0.005 (p<0.05 value, which means that there are significant differences in pH of saliva before and after the application of pit and fissure sealant made from Bis-GMA resin.

Migration of radionuclides in fissured rock - The influence of micropore diffusion and longitudinal dispersion

International Nuclear Information System (INIS)

Rasmuson, A.; Neretnieks, I.

1979-12-01

The migration of radionuclides in the fissures in the bedrock surrounding a repository is discussed. A one-dimensional transport model is presented. It includes diffusion of the nuclides into the microfissures of the rock, and linear sorption and longitudinal dispersion in the bedrock. An analytical solution to the model is given in terms of an infinite integral. The integrand is a sometimes highly oscillatory function of the system parameters. A special integration method is developed to evaluate the infinite integral. The method utilizes the oscillatory behavior of the integrand. The assessment of input parameters is discussed in some detail. Dimensionless breakthrough curves are given for the approximate range of variation of the input parameters. Calculations are made for a repository of spent fuel surrounded by fissured but fairly good rock (K(sub)p=10- 9 m/s and fissure spacing S=50 m). Longitudinal dispersion may significantly affect the amount of radioactive material reaching the biosphere. Radionuclides, which would decay completely without longitudinal dispersion, may arrive in non-negligible concentrations. Dispersion effects of the magnitude considered in this study can significantly diminish the retardation effects of matrix diffusion. (authors)

Migration of radionuclides in fissured rock: The influence of micropore diffusion and longitudinal dispersion

International Nuclear Information System (INIS)

Rasmuson, A.; Neretnieks, I.

1981-01-01

The migration of radionuclides in the fissures in the bedrock surrounding a repository is discussed. A one-dimensional transport model is presented. It includes diffusion of the nuclides into the microfissures of the rock, and linear sorption, and longitudinal dispersion in the bedrock. An analytical solution to the model is given in terms of an infinite integral. The integrand is a sometimes highly oscillatory function of the system parameters. A special integration method is developed to evaluate the infinite integral. The method utilizes the oscillatory behavior of the integrand. The assessment of input parameters is discussed in some detail. Dimensionless breakthrough curves are given for the approximate range of variation of the input parameters. Calculations are made for a repository of spent fuel surrounded by fissured but fairly good rock (K/sub p/ = 10 -9 m/s and fissure spacing S = 50 m). Longitudinal dispersion may significantly affect the amount of radioactive material reaching the biosphere. Radionuclides, which would decay completely without longitudinal dispersion, may arrive in nonnegligible concentrations. Dispersion effects of the magnitude considered in this study can significantly diminish the retardation effects of matrix diffusion

Causes of the fissure formation with shrinkage of metal on low carbon steel slabs

International Nuclear Information System (INIS)

Ksenzuk, F.A.; Khudas, A.L.; Zelenskaya, D.P.

1977-01-01

The causes have been investigated underlying the formation of fissures with spread of metal on low-carbon steel slabs during hot rolling. Metallographic investigations of templates from various sections of work pieces from 15-ton ingots of 08 ps (kp) steels have indicated that the fissures on the slabs are formed after the metal spreads along the small plane and the work piece thins out in the course of rolling because of the opening of large thin-walled honeycomb bubbles. The phenomenon was confirmed schematically on a model in the form of a slab-shaped lead specimen with longitudinal hole of a variable diameter close to one of the edges

Fissured and geographic tongue in Williams-Beuren syndrome

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Neeta Sharma

2014-01-01

Full Text Available Williams-Beuren Syndrome (WBS is a rare, most often sporadic, genetic disease caused by a chromosomal microdeletion at locus 7q11.23 involving 28 genes. It is characterized by congenital heart defects, neonatal hypercalcemia, skeletal and renal abnormalities, cognitive disorder, social personality disorder, and dysmorphic facies. A number of clinical findings has been reported, but none of the studies evaluated this syndrome considering oral cavity. We here report a fissured and geographic tongue in association with WBS.

Fine mapping and introgressing qFIS1-2, a major QTL for kernel fissure resistance in rice (Oryza sativa L.)

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Rice (Oryza sativa L.) kernel fissuring increases breakage during milling and decreases the value of processed rice. This study employed molecular gene tagging methods to fine-map a fissure resistance (FR) locus in ‘Cybonnet’, a semidwarf tropical japonica cultivar, as well as transfer this trait to...

Effect of Intermittent Drying Conditions on Fissuring Percentage and Process Duration of Long and Medium Rough Rice Varieties

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A. Ghasemi

2016-02-01

Full Text Available One of the factors which affect the quality of rice during milling is internal fissures created during and after drying operation. In many industrial countries intermittent drying method is hired to reduce the moisture content of rough rice in order to reduce the drying time and maintain the quality of the final product. A high percentage of rice breakage during milling process, at least in Iran, necessitates performing the intermittent drying process and optimize it for Iranian varieties. In this study, the effect of this method (drying-tempering and continuous drying method (no tempering on fissuring percentage of Hashemi (long grain and Koohsar (medium grain varieties was investigated. The experiments were carried out at constant drying and tempering temperature of 60 °C, drying durations of 20, 40 and 60 min, and tempering durations of 0 (continuous drying, 40, 80, 120, 160, 200, 240 min. The results revealed that the tempering process significantly reduced the drying time and fissured kernels percentage. Moreover, for both varieties it was observed that the rice fissuring decreased significantly by continuing the tempering process until certain durations. Overall, for optimization of intermittent drying process in terms of the considered qualitative parameters, i.e. reducing energy consumption and losses, conducting 160 and 200 min tempering process after 40 min drying was found appropriate for Hashemi and Koohsar varieties, respectively. In addition, according to the higher fissuring for Koohsar (medium grain compared to Hashemi (long grain, it can be concluded that physical properties such as kernel slenderness ratio is effective on its fissuring.

Enamel pretreatment with Er:YAG laser: effects on the microleakage of fissure sealant in fluorosed teeth

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Mahtab Memarpour,

2014-08-01

Full Text Available Objectives The purpose of this in vitro study was to evaluate the microleakage and penetration of fissure sealant in permanent molar teeth with fluorosis after pretreatment of the occlusal surface. Materials and Methods A total of 120 third molars with mild dental fluorosis were randomly divided into 6 groups (n = 20. The tooth surfaces were sealed with an unfilled resin fissure sealant (FS material. The experimental groups included: 1 phosphoric acid etching (AE + FS (control; 2 AE + One-Step Plus (OS, Bisco + FS; 3 bur + AE + FS; 4 bur + AE + OS + FS; 5 Er:YAG laser + AE + FS; and 6 Er:YAG laser + AE + OS + FS. After thermocycling, the teeth were immersed in 0.5% fuchsin and sectioned. Proportions of mircoleakage (PM and unfilled area (PUA were measured by digital microscope. Results Overall, there were significant differences among all groups in the PM (p = 0.00. Group 3 showed the greatest PM, and was significantly different from groups 2 to 6 (p < 0.05. Group 6 showed the lowest PM. Pretreatment with Er:YAG with or without adhesive led to less PM than bur pretreatment. There were no significant differences among groups in PUA. Conclusions Conventional acid etching provided a similar degree of occlusal seal in teeth with fluorosis compared to those pretreated with a bur or Er:YAG laser. Pretreatment of pits and fissures with Er:YAG in teeth with fluorosis may be an alternative method before fissure sealant application.

Posterior perineal support as treatment for anal fissures--preliminary results with a new toilet seat device.

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Tan, Kok-Yang; Seow-Choen, Francis; Hai, Chew Heng; Thye, Gan Kok

2009-03-01

Anal fissures can cause morbidity in an otherwise healthy young patient. The process of evacuation results in stretching and descent of the anoderm and perineum especially posteriorly. Posterior perineal support may provide counter pressure at the posterior aspect of the pelvic floor, balancing the pressure exerted by the faeces on the anal wall, thus improving evacuation and reducing the trauma associated with it, and reducing symptoms of anal fissures. Symptoms of constipation may also be reduced secondarily. We report the preliminary results with a novel, simple and noninvasive method of treatment provided by a toilet seat device. A prospective study was performed in 32 patients. The study was designed mainly to investigate the patients' subjective perceptions of their symptoms related to anal fissures and constipation. Questionnaires were provided to patients before, during and after treatment. The study revealed statistically significant improvement in pain, bleeding, symptoms of constipation and abdominal discomfort after 3 months usage of the device. The odds of patients perceiving an improvement in symptoms were also significantly increased after 3 months of treatment compared to 2 weeks of treatment. This preliminary study revealed that a posterior perineal support device can bring about significant improvement in the symptoms of patients with anal fissures. There may also be secondary benefits of a reduction in the symptoms of constipation. Although not conclusive, these results should serve as a springboard for further research into this area.

Ground fissures in the area of Mavropigi Village (N. Greece): Seismotectonics or mining activity?

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Kalogirou, Eleni; Tsapanos, Theodoros; Karakostas, Vassilios; Marinos, Vassilios; Chatzipetros, Alexandros

2014-12-01

In the beginning of July 2010, a ground fissure was observed in the field near the village of Mavropigi (Northern Greece) and specifically in its NW side. Later on (early September), a second ground fissure was perceived, close and almost parallel to the first one and very close to the limits of the lignite exploitation mine (by the Public Power Corporation, PPC). It was observed that the village of Mavropigi slides away slowly towards the PPC lignite mine. Geological, seismological, as well as geotechnical survey in the field indicated that the phenomenon is related to the coal mining exploitation in the near vicinity of the village rather than to any seismotectonic activity in the surrounding area.

Endoscopic endonasal anatomy of superior orbital fissure and orbital apex regions: critical considerations for clinical applications.

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Dallan, Iacopo; Castelnuovo, Paolo; de Notaris, Matteo; Sellari-Franceschini, Stefano; Lenzi, Riccardo; Turri-Zanoni, Mario; Battaglia, Paolo; Prats-Galino, Alberto

2013-05-01

The superior orbital fissure is a critical three-dimensional space connecting the middle cranial fossa and the orbit. From an endoscopic viewpoint, only the medial aspect has a clinical significance. It presents a critical relationship with the lateral sellar compartment, the pterygopalatine fossa and the middle cranial fossa. The connective tissue layers and neural and vascular structures of this region are described. The role of Muller's muscle is confirmed, and the utility of the maxillary and optic strut is outlined. Muller's muscle extends for the whole length of the inferior orbital fissure, passes over the maxillary strut and enters the superior orbital fissure, representing a critical surgical landmark. Dividing the tendon between the medial and inferior rectus muscle allows the identification of the main trunk of the oculomotor nerve, and a little laterally, it is usually possible to visualize the first part of the ophthalmic artery. Based on a better knowledge of anatomy, we trust that this area could be readily addressed in clinical situations requiring an extended approach in proximity of the orbital apex.

Superior vesical fissure concealed by giant omphalocele: A case report

OpenAIRE

Hayek, Danial; Massanyi, Eric; Mancuso, Melissa; Krepkovich, Katherine; Garrison, Aaron

2016-01-01

Omphalocele is an abdominal wall defect characterized by exteriorization of abdominal viscera that is covered by a membrane. Omphalocele has a well-known association with chromosome abnormalities. Here we present a case of a superior vesical fissure (SVF) initially disguised as a giant omphalocele in a newborn with trisomy 18. We also show unique prenatal imaging and discuss the importance and limitations of prenatal genetic testing.

Salt geologic evaluation of the impact of cryogenic fissures and halokinetic deformation processes on the integrity of the geological barrier of the salt dome Gorleben

International Nuclear Information System (INIS)

Hammer, Joerg; Fleig, Stephanie; Mingerzahn, Gerhard

2012-07-01

In several salt domes of the area close to Hannover fissures were observed that might be caused by thermally induced fissure formation due to cold periods (cryogenic fissures). Comprehensive substantial-structural analyses are performed as an example for the salt dome Bokeloh with respect to genesis and transferability to the salt dome Gorleben. Based on recent structure-geological, mineralogical-geochemical and micro-paleontological studies and thermo-mechanical modeling a solely thermally induced fissure formation due to cold periods is unlikely for the salt dome Bokeloh. There is a direct relation between the genesis of the salt dome Bokeloh, its regional tectonic site and the fissure formation. Due to the completely different genesis and another regional-tectonic situation the existence of cryogenic fissures is excluded for the salt dome Gorleben. The salt-geologic and experimental studies on the deformation of anhydrite layers in salt domes are summarized and evaluated with respect to the long-term consequences for a potential final repository for high-level heat-generating radioactive waste in the salt dome Gorleben. The studies confirm the older BGR studies that anhydrite layers do not represent hydraulic potential ling-distance liquid paths.

Evolution of oceanic molybdenum and uranium reservoir size around the Ediacaran-Cambrian transition: Evidence from western Zhejiang, South China

Science.gov (United States)

Xiang, Lei; Schoepfer, Shane D.; Shen, Shu-zhong; Cao, Chang-qun; Zhang, Hua

2017-04-01

The "Cambrian explosion" is one of the most fascinating episodes of diversification in the history of life; however, its relationship to the oxygenation of the oceans and atmosphere around the Ediacaran-Cambrian transition is not fully understood. Marine inventories of redox-sensitive trace elements reflect the relative balance of oxidative weathering on land and deposition in anoxic water masses, and can be used to explore the evolution of oceanic and atmospheric redox conditions. For this study, we conducted a series of geochemical analyses on the upper Lantian, Piyuancun, and Hetang formations in the Chunye-1 well, part of the lower Yangtze Block in western Zhejiang. Iron speciation results indicate that the entire studied interval was deposited under anoxic conditions, with three intervals of persistent euxinia occurring in the uppermost Lantian Fm., the lower Hetang Formation (Fm.), and the upper Hetang Fm. Molybdenum (Mo) and uranium (U) contents and Mo/TOC and U/TOC ratios from the anoxic/euxinic intervals of the Chunye-1 well, combined with published data from the sections in the middle and upper Yangtze Block, suggest that the oceanic Mo reservoir declined consistently from the Ediacaran to Cambrian Stage 3, while the size of the oceanic U reservoir remained relatively constant. Both metals were depleted in the ocean in lower Cambrian Stage 4, before increasing markedly at the end of Stage 4. The lack of an apparent increase in the size of the marine Mo and U reservoir from the upper Ediacaran to Cambrian Stage 3 suggests that oxic water masses did not expand until Cambrian Stage 4. The increase in marine Mo and U availability in the upper Hetang Fm. may have been due to the expansion of oxic water masses in the oceans, associated with oxygenation of the atmosphere during Cambrian Stage 4. This expansion of oxic waters in the global ocean postdates the main phase of Cambrian diversification, suggesting that pervasive oxygenation of the ocean on a large

Desenvolvimento das fissuras cerebrais fetais: avaliação com ultrassonografia tridimensional Fetal brain fissures development a three-dimensional ultrasonography study

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Cynthia Maria Soares Alves

2011-03-01

Full Text Available OBJETIVO: avaliar a distância das fissuras cerebrais fetais à borda interna da calota craniana por meio da ultrassonografia tridimensional (US3D. MÉTODOS: realizou-se um estudo de corte transversal em 80 gestantes normais entre a 21ª e 34ª semanas de gestação. Avaliou-se a distância entre a tábua óssea interna da calota craniana fetal e as fissuras de Sylvius, parieto-occipital, hipocampo e calcarina. Para a obtenção desta distância para as três primeiras fissuras, realizou-se uma varredura tridimensional através do plano axial (nível dos ventrículos laterais. Para a obtenção da distância da fissura calcarina utilizou-se uma varredura coronal (nível dos lobos occiptais. Para avaliar a correlação entre as fissuras e a idade gestacional foram realizadas regressões de primeiro grau, sendo os ajustes calculados pelo coeficiente de determinação (R². Foram determinados percentis 5, 50 e 95 para cada fissura. Avaliou-se ainda a correlação entre a distância destas fissuras com os diâmetros biparietal (DBP e circunferência craniana (CC utilizando o coeficiente de correlação de Pearson (r. RESULTADOS: todas as medidas das fissuras apresentaram correlação linear com a idade gestacional (Sylvius: R²=0,5; parieto-occipital: R²=0,7; hipocampo: R²=0,3 e calcarina: R²=0,3. A média da distância das fissuras variou de 7,0 a 14,0 mm, 15,9 a 28,7 mm, 15,4 a 25,4 mm e 15,7 a 24,8 mm para as fissuras de Sylvius, parieto-occipital, hipocampo e calcarina, respectivamente. As fissuras de Sylvius e parieto-occipital apresentaram as maiores correlações com o DBP (r=0,8 e 0,7, respectivamente e a CC (r=0,7 e 0,8, respectivamente. CONCLUSÕES: a distância das fissuras cerebrais fetais à borda interna da calota craniana por meio da US3D apresentou correlação positiva com a idade gestacional.PURPOSE: to assess the distance of the fetal cerebral fissures from the inner edge of the skull by three-dimensional ultrasonography (3DUS

Superior vesical fissure concealed by giant omphalocele: A case report

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Danial Hayek

2016-11-01

Full Text Available Omphalocele is an abdominal wall defect characterized by exteriorization of abdominal viscera that is covered by a membrane. Omphalocele has a well-known association with chromosome abnormalities. Here we present a case of a superior vesical fissure (SVF initially disguised as a giant omphalocele in a newborn with trisomy 18. We also show unique prenatal imaging and discuss the importance and limitations of prenatal genetic testing.

Microleakage assessment of fissure sealant following fissurotomy bur or pumice prophylaxis use before etching

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Ali Bagherian

2013-01-01

The aim of this investigation was to compare the microleakage level of fissure sealants prepared by a fissurotomy bur or pumice prophylaxis prior to acid etching. Materials and Methods: Ninety freshly extracted healthy maxillary premolar teeth were randomly selected for this investigation. Teeth were then divided into three fissure sealant preparatory groups of A: Fissurotomy bur + acid etch; B: Pumice prophylaxis + acid etch and C: Acid etch alone. Sealant was applied to the occlusal fissures of all specimens using a plastic instrument. This was to avoid any air trap under the sealant. Sample teeth were first thermocycled (1000 cycles, 20 s dwell time and then coated with two layers of nail varnish leaving 2 mm around the sealant. This was then followed by immersion in basic fuchsin 3%. Processed teeth were sectioned longitudinally and examined under a stereomicroscope for microleakage assessment using a score of 0-3. Collected data was then subjected to Kruskall-Wallis Analysis of Variance and Mann-Whitney U-test. P < 0.05 was considered as significant. Results: Teeth in fissurotomy bur and pumice prophylaxis groups had significantly reduced level of microleakage than those in acid etch alone (P = 0.005 and P = 0.003, respectively. Conclusion: Use of fissurotomy bur and pumice prophylaxis accompanied with acid etching appears to have a more successful reduction of microleakage than acid etch alone.

Giant desiccation fissures on the Black Rock and Smoke Creek Deserts, Nevada

Science.gov (United States)

Willden, R.; Mabey, D.R.

1961-01-01

Open fissures, from 100 to several hundred feet apart, that have produced polygonal patterns on the Black Rock Desert, Nevada, are believed to be giant desiccation cracks resulting from a secular trend toward aridity in the last few decades. Similar features on the Smoke Creek Desert probably have the same origin.

Soil gas geochemistry in relation to eruptive fissures on Timanfaya volcano, Lanzarote Island (Canary Islands, Spain)

Science.gov (United States)

Padrón, Eleazar; Padilla, Germán; Hernández, Pedro A.; Pérez, Nemesio M.; Calvo, David; Nolasco, Dácil; Barrancos, José; Melián, Gladys V.; Dionis, Samara; Rodríguez, Fátima

2013-01-01

We report herein the first results of an extensive soil gas survey performed on Timanfaya volcano on May 2011. Soil gas composition at Timanfaya volcano indicates a main atmospheric source, slightly enriched in CO2 and He. Soil CO2 concentration showed a very slight deep contribution of the Timanfaya volcanic system, with no clear relation to the main eruptive fissures of the studied area. The existence of soil helium enrichments in Timanfaya indicates a shallow degassing of crustal helium and other possible deeper sources probably form cooling magma bodies at depth. The main soil helium enrichments were observed in good agreement with the main eruptive fissures of the 1730-36 eruption, with the highest values located at those areas with a higher density of recent eruptive centers, indicating an important structural control for the leakage of helium at Timanfaya volcano. Atmospheric air slightly polluted by deep-seated helium emissions, CO2 degassed from a cooling magma body, and biogenic CO2, might be the most plausible explanation for the existence of soil gas. Helium is a deep-seated gas, exhibiting important emission rates along the main eruptive fissure of the 1730-36 eruption of Timanfaya volcano.

Soil gas composition from the 2001-2002 fissure in the Lakki Plain (Nisyros Island, Greece): evidences for shallow hydrothermal fluid circulation

Science.gov (United States)

Venturi, Stefania; Tassi, Franco; Kanellopoulos, Christos; Vaselli, Orlando; Caponi, Chiara; Ricci, Andrea; Raspanti, Alessio; Gallorini, Andrea; Cabassi, Jacopo; Vougioukalakis, Georges

2016-04-01

Nisyros volcano (Aegean Sea, Greece) is currently classified in the "Very High Threat" category (Kinvig et al., 2010). Although the last volcanic activity, consisting of phreatic eruptions, occurred in the 19th century, Nisyros experienced an intense seismic activity during 1996-1998 accompanied by ground deformation and changes in the chemistry of fumarolic gases (Chiodini et al., 2002), pointing to a renewed unrest. Between November 2001 and December 2002, a NNE-oriented 600 m long fissure opened in the vegetated central part of the Lakki Plain. The fissure, 1-5 m wide and up to 15-20 m deep, showed neither vertical displacements nor gas release. No changes in the seismic and volcanic activity were observed during or after this event, which was interpreted as related to collapse of the upper caldera floor fine sediment cover (permeable sediment cover in the Lakki Plain conceals the underneath hydrothermal gas flow, preventing the typical surface manifestations (high temperature and CO2 flux), the chemistry of the interstitial gases reveals that deep-sourced fluids circulate within the deep permeable layers beneath the Lakki Plain enhancing alteration processes and formation of shallow collapsing structures. Chiodini G., Brombach T., Caliro S., Cardellini C., 2002. Geophys Res Lett, 29(16), 1759. Kinvig H.S., Winson A., Gottsmann J., 2010. Nat Hazards Earth Syst Sci, 10. Vougioukalakis G.E., Fytikas M., 2005. In Fytikas M., Vougioukalakis G.E. (Eds.), The South Aegean Active Volcanic Arc, Present Knowledge and Future Perspectives, Developments in Volcanology, Elsevier, Amsterdam The Netherlands, 2005, pp. 161-163.

Rice fissure resistance QTLs from ‘Saber’ complement those from ‘Cypress’

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The economic value of broken rice is about half that of whole milled rice, so one goal of producers, millers, and rice breeders is to reduce grain breakage during the dehusking and milling processes. One of the primary causes of rice breakage is fissuring, or cracking, of the rice before it enters ...

Evaluation of microtensile bond strength of different fissure sealants to bovine enamel.

Science.gov (United States)

Sen Tunc, E; Bayrak, S; Tuloglu, N; Ertas, E

2012-03-01

The aim of this study was to evaluate the microtensile bond strength (μTBS) of a new fissure sealant and compare it with conventional sealants which are applied to enamel alone, and also with self-etch and etch-and-rinse adhesives. Enamel specimens were prepared and randomly distributed into three groups according to fissure sealant (Aegis, Helioseal F, Helioseal Clear). Each group was then subdivided according to adhesive system (Clearfil S3, Single Bond, no adhesive). A universal testing machine was used to measure μTBS, and data were analysed using one-way ANOVA and Tukey's tests. μTBS values for all Aegis subgroups were significantly lower than for comparable Helioseal F and Helioseal Clear subgroups (p 0.05). In the Helioseal Clear group, μTBS values for Single Bond were significantly higher than for Clearfil S3 (p adhesive subgroups in the Aegis or Helioseal F groups (p > 0.05). Sealant μTBS values may be affected by material content. The addition of an adhesive may improve μTBS values of sealant to enamel. © 2012 Australian Dental Association.

[Banana peel: a possible source of infection in the treatment of nipple fissures].

Science.gov (United States)

Novak, Franz Reis; de Almeida, João Aprígio Guerra; de Souza e Silva, Rosana

2003-01-01

To study the microbiology of banana peel being sold in the city of Rio de Janeiro, in an attempt to determine the possibility that the peel may represent a source of infection for women who use it to treat nipple fissures. The following microorganisms were studied in 20 banana peel samples: mesophiles, total coliforms, fecal coliforms, Pseudomonas aeruginosa, lipolytic and proteolytic microorganisms, molds and yeasts, lactic bacteria, and coagulase-positive staphylococcus. The microbiological analyses revealed the occurrence of several typical groups of microorganisms, with the following distribution of positive results being detected in banana peel samples: mesophiles, 100%; total coliforms, 20%; coagulase-positive staphylococcus, 25%; molds and yeasts, 30%; proteolytic microorganisms, 70%; lipolytic microorganisms, 30%, and lactic bacteria, 95%. Fecal coliforms and Pseudomonas aeruginosa were not isolated. The results show the presence of potentially pathogenic microorganisms in levels which could compromise the microbiological quality of the banana peel. Its use for the treatment of nipple fissures can initiate an infectious process.

Groundwater flow through fissured rock: field investigations and interpretation in the Albigna dam area, Graubuenden, Switzerland

International Nuclear Information System (INIS)

Kovari, K.; Arn, Th.; Gmuender, Ch.

1989-11-01

The rock foundation of a dam was chosen as the site for repeated observations of flow patterns in a fissured rock. Our project was carried out at the Albigna Dam in the Canton of Graubuenden, Switzerland, where the greatest fluctuation in the level of the lake was approximately 100 m. In the area of the dam the rock consists of a fresh, solid granite, whose fissure systems were well known as regards position and distribution. The measurement program for assessing the flow conditions consisted of two elements: piezometric pressure measurements in boreholes and strain measurements in boreholes. Pressure measurements were accomplished to define the potential field. Strain measurements were accomplished to detect fracture opening and closing as a function of the fluctuations in the lake level. From a combination of the two sets of observations it was hoped to be able to determine the interaction between hydraulics and mechanics, i.e. the coupling of two key processes with a possible influence on a changing permeability of the rock. Using the 'sliding micrometer', the continuous strain distribution was determined along two boreholes in the measuring plane. Pressures were measured using the 'Piezodex' system. Mathematical investigations were conducted with the AQUA-ROCK finite element program on a 2D-model. From just a visual comparison of the measured and calculated values it is clear that a different model achieves the best correlation depending on the level of the lake. For the maximum lake level, however, it is essential to take account of the action of the fissures either by way of the idealization according to Snow (main model 2) or by considering the individual fissures (main model 3). (author) figs., tabs., 12 refs

Chronic anal fissure: morphometric analysis of the anal canal at 3.0 Tesla MR imaging.

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Erden, Ayşe; Peker, Elif; Gençtürk, Zeynep Bıyıklı

2017-02-01

OBJECTıVE: To compare the morphometric data relating to the muscular structures of the anal canal, in patients with chronic anal fissure and in control group, examined at a 3.0 Tesla MR system. Forty-seven consecutive patients with chronic anal fissure and randomly selected 40 patients who had no claims for perianal disease during their life time were included in the study. T2-weighted sagittal, high-resolution (HR) T2-weighted, and contrast-enhanced fat-suppressed T1-weighted oblique axial and oblique coronal images were retrospectively analyzed by two observers in consensus. Thickness of sphincteric muscles, anal canal length, anorectal angle, thickness of anococcygeal ligament, depth of Minor triangle, width between subcutaneous sphincters, vascularity of posterior commissure, visibility of posterosuperior projection of external sphincter, and angle between the distal anal canal and posterosuperior projection of external sphincter (H angle) in patients and in controls were compared and analyzed using t test, Mann-Whitney U test, and Spearman correlation. The patients with chronic anal fissure had longer anal canal (51.50 mm ± 0.91 vs. 44.11 mm ± 0.71; p = 0.000), thicker internal anal sphincter muscle at mid-anal level (4.18 ± 0.15 vs. 3.39 ± 0.07; p = 0.007), and wider space between subcutaneous external sphincters (11.39 ± 0.50 vs. 6.89 ± 0.22; p = 0.000). In patients, there was a positive correlation between H angle and external sphincter thickness at proximal (r = 0.347; p = 0.021), middle (r = 0427; p = 0.000), and distal (r = 0.518; p = 0.000)) levels of the anal canal. CONCLUSıON: 3.0 Tesla MR imaging provides detailed information about the morphometric changes in the anal sphincter muscles in patients with chronic anal fissure.

Flows of Newtonian and Power-Law Fluids in Symmetrically Corrugated Cappilary Fissures and Tubes

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Walicka, A.

2018-02-01

In this paper, an analytical method for deriving the relationships between the pressure drop and the volumetric flow rate in laminar flow regimes of Newtonian and power-law fluids through symmetrically corrugated capillary fissures and tubes is presented. This method, which is general with regard to fluid and capillary shape, can also be used as a foundation for different fluids, fissures and tubes. It can also be a good base for numerical integration when analytical expressions are hard to obtain due to mathematical complexities. Five converging-diverging or diverging-converging geometrics, viz. wedge and cone, parabolic, hyperbolic, hyperbolic cosine and cosine curve, are used as examples to illustrate the application of this method. For the wedge and cone geometry the present results for the power-law fluid were compared with the results obtained by another method; this comparison indicates a good compatibility between both the results.

Flows of Newtonian and Power-Law Fluids in Symmetrically Corrugated Cappilary Fissures and Tubes

Directory of Open Access Journals (Sweden)

Walicka A.

2018-02-01

Full Text Available In this paper, an analytical method for deriving the relationships between the pressure drop and the volumetric flow rate in laminar flow regimes of Newtonian and power-law fluids through symmetrically corrugated capillary fissures and tubes is presented. This method, which is general with regard to fluid and capillary shape, can also be used as a foundation for different fluids, fissures and tubes. It can also be a good base for numerical integration when analytical expressions are hard to obtain due to mathematical complexities. Five converging-diverging or diverging-converging geometrics, viz. wedge and cone, parabolic, hyperbolic, hyperbolic cosine and cosine curve, are used as examples to illustrate the application of this method. For the wedge and cone geometry the present results for the power-law fluid were compared with the results obtained by another method; this comparison indicates a good compatibility between both the results.

Groundwater drainage from fissures as a source for lahars

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Johnson, P. J.; Valentine, G. A.; Stauffer, P. H.; Lowry, C. S.; Sonder, I.; Pulgarín, B. A.; Santacoloma, C. C.; Agudelo, A.

2018-04-01

One mechanism for generating lahars at volcanoes experiencing unrest is the disruption of internal aquifers. These disruptions can trigger releases of large quantities of groundwater. An example of such aquifer disruption occurred at Nevado del Huila Volcano, Colombia, during February and April 2007 when large fractures formed across the summit area of the volcano and lahars were emitted from them. Previous work interpreted that lahar volumes could not be accounted for by melted glacial snow or precipitation, and by elimination suggested that the primary water source was groundwater. Conceptual models have been developed for perched, confined aquifers that have been heated and pressurized by magma intrusions, followed by sudden pressure release and water emission during fracture formation. We consider an alternative end member wherein water release from large fissures at volcanoes is driven by simple gravity drainage. We apply numerical modeling to quantify water discharge from the porous medium surrounding a fissure with a low-elevation free exit. If a long fracture with high vertical extent (on the order of hundreds of meters) intersects a highly connected saturated porous medium, large volumes (on order 103 m3/m of crack length) of water may be released within tens of minutes. The drainage rates from the model may be adequate to account for the Nevado del Huila events if the medium surrounding the crack contains a large volume of water and has high horizontal permeability. This simple but poorly understood mechanism can present a hazard on its own or compound other processes releasing water from volcanoes.

Dynamics of leaching a uniformly fissured ore body

International Nuclear Information System (INIS)

Ignatov, A.A.; Proskurin, S.A.

1987-01-01

Mathematical simulation was used to study the dynamics of mass transfer during the percolation of a reagent solution through a packing of coarse ore particles. The uniformly fissured ore body was represented by a cubic packing of spherical particles of constant radius, formed from a chemically inert silicate cement with a uniformly distributed soluble mineral component. The rate of percolation of the reagent through the packing was constant. The proposed model can be used to find the conditions for underground hydrodynamic leaching. The rate of non-catalytic solid-liquid reaction was deduced on the basis of both the kinetics of dissolution of the mineral component of the ore and the rate of diffusion of the dissolved substance

Optimal Dosing of Botulinum Toxin for Treatment of Chronic Anal Fissure: A Systematic Review and Meta-Analysis.

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Lin, Jin Xin; Krishna, Sanjeev; Su'a, Bruce; Hill, Andrew G

2016-09-01

Chronic anal fissures are associated with significant morbidity and reduced quality of life. Studies have investigated the efficacy of botulinum toxin with variable results; thus, there is currently no consensus on botulinum toxin dose or injection sites. This study aimed to systematically analyze trials studying the efficacy of botulinum toxin for treatment of chronic anal fissure to identify an optimum dosage and injection regimen. A comprehensive review of the literature was conducted according to PRISMA guidelines. PubMed/Medline, Embase, Scopus, and the Cochrane Library were searched from inception to June 2015. All clinical trials that investigated the efficacy of botulinum toxin for chronic anal fissure were selected according to specific criteria. The interventions used were various doses of botulinum toxin. Clinical outcomes, dosage, and injection site data were evaluated with weighted pooled results for each dosage and 95% confidence intervals. There were 1158 patients, with 661 in botulinum toxin treatment arms, from 18 clinical trials included in this review. The outcomes of interest were 3-month healing, incontinence, and recurrence rates. Meta-regression analysis demonstrated a small decrease in healing rate (0.34%; 95% CI, 0-0.68; p = 0.048) with each increase in dosage, a small increase in incontinence rate (1.02 times; 95% CI, 1.0002-1.049; p = 0.048) with each increase in dosage and a small increase in recurrence rate (1.037 times; 95% CI, 1.018-1.057; p = 0.0002) with each increase in dosage. The optimum injection site could not be determined. This study was limited by weaknesses in the underlying evidence, such as variable quality, short follow-up, and a limited range of doses represented. Fissure healing with lower doses of botulinum toxin is as effective as with high doses. Lower doses also reduce the risk of incontinence and recurrence in the long term.

Simulation of the Flow Through Porous Layers Composed of Converging-Diverging Capillary Fissures or Tubes

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Walicka, A.

2018-02-01

In this paper, a porous medium is modelled by a network of converging-diverging capillaries which may be considered as fissures or tubes. This model makes it necessary to consider flows through capillary fissures or tubes. Therefore an analytical method for deriving the relationships between pressure drops, volumetric flow rates and velocities for the following fluids: Newtonian, polar, power-law, pseudoplastic (DeHaven and Sisko types) and Shulmanian, was developed. Next, considerations on the models of pore network for Newtonian and non-Newtonian fluids were presented. The models, similar to the schemes of central finite differences may provide a good basis for transforming the governing equations of a flow through the porous medium into a set of linear or quasi-linear algebraic equations. It was shown that the some coefficients in these algebraic equations depend on the kind of the capillary convergence.

Fissure sealant materials: Wear resistance of flowable composite resins.

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Asefi, Sohrab; Eskandarion, Solmaz; Hamidiaval, Shadi

2016-01-01

Background. Wear resistance of pit and fissure sealant materials can influence their retention. Wear characteristics of sealant materials may determine scheduling of check-up visits. The aim of this study was to compare wear resistance of two flowable composite resins with that of posterior composite resin materials. Methods. Thirty-five disk-shaped specimens were prepared in 5 groups, including two flowable composite resins (Estelite Flow Quick and Estelite Flow Quick High Flow), Filtek P90 and Filtek P60 and Tetric N-Ceram. The disk-shaped samples were prepared in 25-mm diameter by packing them into a two-piece aluminum mold and then light-cured. All the specimens were polished for 1minute using 600-grit sand paper. The samples were stored in distilled water at room temperature for 1 week and then worn by two-body abrasion test using "pin-on-disk" method (with distilled water under a 15-Nload at 0.05 m/s, for a distance of 100 meter with Steatite ceramic balls antagonists). A Profilometer was used for evaluating the surface wear. Data were analyzed with the one-way ANOVA. Results. Estelite Flow Quick exhibited 2708.9 ± 578.1 μm(2) and Estelite Flow Quick High Flow exhibited 3206 ± 2445.1 μm(2)of wear but there were no significant differences between the groups. They demonstrated similar wear properties. Conclusion. Estelite flowable composite resins have wear resistance similar to nano- and micro-filled and micro-hybrid composite resins. Therefore, they can be recommended as pit and fissure sealant materials in the posterior region with appropriate mechanical characteristics.

Deep Structure of the Zone of Tolbachik Fissure Eruptions (Kamchatka, Klyuchevskoy Volcano Group): Evidence from a Complex of Geological and Geophysical Data

Science.gov (United States)

Kugaenko, Yu. A.; Saltykov, V. A.; Gorvatikov, A. V.; Stepanova, M. Yu.

2018-05-01

With the use of the method of low-frequency microseismic sounding, the configuration of the magmatic feeding system of the Tolbachinsky Dol—a regional zone of areal basaltic volcanism in the southern part of the Klyuchevskoy volcano group in Kamchatka—is studied. The initial data are obtained by a stepby-step recording of the background microseismic noise in 2010-2015 within a thoroughly marked-out survey area covering the zones of fissure eruptions in 1975-1976 and 2012-2013 and, partly, the edifice of the Ploskii (flat) Tolbachik volcano. The depth sections reflecting the distributions of the relative velocities of seismic waves in the Earth's crust are constructed. For a more reliable interpretation of the revealed deep anomalies, the results of independent geological and geophysical studies are used. The ascertained low-velocity structures are closely correlated to the manifestations of present-day volcanism. It is shown that the feeding structure of the Tolbachinsky Dol is spatially heterogeneous, incorporating subvertical and lateral pipeshaped magma conduits, closely spaced magma feeding channels, and shallow magma reservoirs. A longlived local transcrustal magma conducting zone is revealed, and regularities in the deep structure of the feeding systems of fissure eruptions are identified. The configuration of the established subvertical magma conduits permits basalts moving to rise to the surface by different paths, which, inter alia, explains the contrasting magma compositions observed during a single eruption. Thus, based on the instrumental data, it is shown that the magmatic feeding structure of the Tolbachinsky Dol has a number of specific peculiarities and is significantly more complicated than has been previously thought about the areal volcanic fields.

Spontaneous Cerebrospinal Fluid Otorrhea from a Persistent Tympanomeningeal Fissure Presenting as Recurrent Serous Otitis Media

DEFF Research Database (Denmark)

Zakaryan, Arman; Poulsgaard, Lars; Hollander, Camilla

2015-01-01

We describe spontaneous cerebrospinal fluid (CSF) otorrhea through a patent tympanomeningeal (Hyrtl) fissure presenting as recurrent serous otitis media. The CSF leak was observed when a drain was placed through the tympanic membrane by an otologist. The diagnosis was then confirmed by computed...

Botulinum toxin A injection for chronic anal fissures and anal sphincter spasm improves quality of life in recessive dystrophic epidermolysis bullosa

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Cassandra Chaptini, MBBS

2015-12-01

Full Text Available We report a 20-year-old female with generalized, severe, recessive dystrophic epidermolysis bullosa who developed secondary chronic anal fissures. This resulted in anal sphincter spasm and severe, disabling pain. She was treated with five botulinum toxin A injections into the internal anal sphincter over a period of 2 years and gained marked improvement in her symptoms. This case demonstrates the successful use of botulinum toxin A injections to relieve anal sphincter spasm and fissuring, with long-term improvement.

Anorectal pain and irritation: anal fissure, levator syndrome, proctalgia fugax, and pruritus ani.

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Vincent, C

1999-03-01

Anal fissures, proctalgia fugax, levator ani syndrome, and pruritus ani are common causes of anorectal pain and irritation. The clinician who obtains a thorough history and performs a complete examination can accurately diagnose these disorders. Ancillary tests seldom are helpful and rarely are necessary. Most patients suffering from these conditions readily respond to conservative therapy provided in the primary care practitioner's office.

Identification of genetic loci underlying the kernel fissure-resistance exhibited by 'cypress' and 'saber'

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The economic value of broken rice is about half that of whole milled rice, so one goal of producers, millers, and rice breeders is to reduce broken grains that result from the dehusking and milling processes One of the primary causes of rice breakage is fissuring, or cracking, of the rice before it ...

Tensions and Fissures: The Politics of Standardised Testing and Accountability in Ontario, 1995-2015

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Pinto, Laura Elizabeth

2016-01-01

While Ontario has received international accolades for its enactment of province-wide standardised testing upon the formation of the Education Quality and Accountability Office (EQAO), a closer look at provincial assessments over a 20-year span reveals successes as well as systemic tensions and fissures. The purpose of this paper is twofold.…

Radionuclide transport in a single fissure

International Nuclear Information System (INIS)

Eriksen, T.E.

1988-12-01

The study of radionuclide migration through rock is currently of great interest due to its relevance to the possible escape paths into the biosphere of radionuclides released from high level radioactive wastes burried in deep geological repositories. While water will provide the vehicle for transportation, interaction with geological material may greatly influence the radionuclide movement relative that of water. A flow system for laboratory studies of radionuclide transport in natural fissures in granitic rock under reducing conditions is described. The system based on the use of synthetic ground water equilibrated with granitic rock in a well sealed system, allow experiments to be carried out at -240 mV reduction potential. In flow experiments with technetium the retardation was found to be dependent on the method used for reducing TcO 4 - . The preparation of the tracer solutions is crucial, as some of the redox-reactions may be very slow. The dynamics of the Tc(VII) reduction and also speciation need to be carried out in separate experiments. (4 illustrations, 5 tables)

Pit and fissure sealants for preventing dental decay in the permanent teeth of children and adolescents

DEFF Research Database (Denmark)

Ahovuo-Saloranta, Anneli; Hiiri, Anne; Nordblad, Anne

2008-01-01

BACKGROUND: Although pit and fissure sealants are effective in preventing caries, their efficacy may be related to the caries prevalence in the population. OBJECTIVES: The primary objective of this review was to evaluate the caries prevention of pit and fissure sealants in children and adolescents...... for comparison of sealant versus sealant. Five split-mouth studies and one parallel group study with 5 to 10 year old children found a significant difference in favour of second or third generation resin-based sealants on first permanent molars, compared to a control without sealant, with a pooled RR of 0.13 (95...... sealant group; 27% of sealed surfaces were decayed compared to 77% of surfaces without sealant.The results of the studies comparing different sealant materials were conflicting. AUTHORS' CONCLUSIONS: Sealing is a recommended procedure to prevent caries of the occlusal surfaces of permanent molars...

Interaction of groundwater and fresh basalt fissure surfaces and its effect on the migration of actinides

International Nuclear Information System (INIS)

Vandegrift, G.F.; Bowers, D.L.; Gerding, T.J.; Fried, S.M.; Wilbur, C.K.; Seitz, M.G.

1983-01-01

Experiments are being performed at Argonne National Laboratory (ANL): (1) to identify interactions of radionuclides and repository components that effect nuclide migration, and (2) to assess changes in nuclide migration caused by modifications expected upon aging of the waste, clay backfill, and rock. The experiments are conducted with radioactive borosilicate glass, bentonite and mechanically fissured basalt rock in flowing water analogous to their configuration in a breach of a nuclear waste repository. Changes undergone by the groundwater as it passed through the fissure include: (1) drop in pH from 10 to 8, (2) loss of suspended particulate, and (3) loss of dissolved/suspended U, Np, and Pu. These effects, also studied as functions of radiation dose and of laboratory aging of the repository components, are related to the predicted long-term performance of a nuclear waste repository

Clinical, manometric, and ultrasonographic results of pneumatic balloon dilatation vs. lateral internal sphincterotomy for chronic anal fissure: a prospective, randomized, controlled trial.

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Renzi, Adolfo; Izzo, Domenico; Di Sarno, Giandomenico; Talento, Pasquale; Torelli, Francesco; Izzo, Giuseppe; Di Martino, Natale

2008-01-01

This prospective, randomized, controlled trial was designed to compare the clinical, functional, and morphologic results of pneumatic balloon dilatation with lateral internal sphincterotomy for the treatment of chronic anal fissure. All patients with symptomatic chronic anal fissure were randomly assigned to pneumatic balloon dilatation or lateral internal sphincterotomy and invited to complete a standardized questionnaire inquiring about their symptoms. Anal ultrasonography and anal manometry were performed before and six months after surgery. A proctologic examination was performed between the fifth and sixth postoperative weeks. Anal continence, scored by using a validated continence grading scale, was evaluated preoperatively at 1 and 6 weeks and at 12 and 24 months. Fifty-three patients, who satisfied selection criteria, were enrolled in the trial. Four patients (7.5 percent) were lost to follow-up. Twenty-four patients (11 males; mean age, 42 +/- 8.2 years) underwent pneumatic balloon dilatation and 25 patients (10 males; mean age, 44 +/- 7.3 years) underwent lateral internal sphincterotomy. Fissure-healing rates were 83.3 percent in the pneumatic balloon dilatation and 92 percent in the lateral internal sphincterotomy group. Recurrent anal fissure was observed in one patient (4 percent) after lateral internal sphincterotomy. At anal manometry, mean resting pressure decrements obtained after pneumatic balloon dilatation and lateral internal sphincterotomy were 30.5 and 34.3 percent, respectively. After pneumatic balloon dilatation, anal ultrasonography did not show any significant sphincter damage. At 24-month follow-up, the incidence of incontinence, irrespective of severity, was 0 percent in the pneumatic balloon dilatation group and 16 percent in the lateral internal sphincterotomy group (P < 0.0001). As lateral internal sphincterotomy, pneumatic balloon dilatation grants a high anal fissure-healing rate but with a statistically significant reduction in

Parents' Attitude towards the Use of Fluorides and Fissure Sealants and its Effect on their Children's Oral Health.

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Blumer, Sigalit; Ratson, Tal; Peretz, Benjamin; Dagon, Nurit

To characterize the attitudes of Israeli parents towards caries preventive measures. participating parents completed a 21-item questionnaire on their demographics, dental history, attitudes and satisfaction from fluorides and fissure sealants. One hundred parents (average age 41.62±4.9 years, 85 females) participated. Most of the parents (88% of the mothers and 84% of the fathers) had an academic education. Most of the parents (54%) had a favorable attitude towards the use of fluoridated gels, while only 37% of them had a positive opinion regarding fluoridated water. The satisfaction levels were very high regarding fissure sealants, fluoridated mouth rinses and fluoridated gels (78.1%, 73.6% and 72.5% respectively). The satisfaction from fluoridated water was split almost equally (50.8% were 'pleased' and 49.2% 'not pleased'). The main source for parental oral health knowledge was the dentist (83%). Parents' attitude towards caries preventive measures was significantly correlated to their gender, dental experience, level of education and the number of children in the family. positive attitude towards caries preventive measures was found among parents with higher awareness for preventive oral health measures and among bigger families. Mothers were more positive about fissure sealants than fathers. Mothers with up to 12 years of education tended to have a positive opinion regarding water fluoridation.

Randomized clinical trial assessing the side-effects of glyceryl trinitrate and diltiazem hydrochloride in the treatment of chronic anal fissure.

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Kocher, H M; Steward, M; Leather, A J M; Cullen, P T

2002-04-01

Glyceryl trinitrate (GTN) ointment (0 small middle dot2 per cent) has an efficacy of up to 68 per cent in healing chronic anal fissure, but with headache as a major side-effect. Diltiazem hydrochloride (DTZ) cream (2 per cent) is expected to have fewer side-effects. A prospective double-blind randomized two-centre trial requiring at least 26 patients in each group (alpha = 0.05, beta = 0.9) was instituted after approval of the local ethics committee, to compare the incidence of side-effects (primary endpoint) with 0.2 per cent GTN ointment and 2 per cent DTZ cream in the treatment of chronic anal fissure. Treatments were applied perianally, twice daily for 6-8 weeks. All patients gave written informed consent. Both groups were comparable in patient demographics and clinical characteristics. Twelve patients violated the protocol, withdrew or did not attend follow-up. There were more side-effects with GTN (21 of 29 patients) than with DTZ (13 of 31) (relative risk (RR) 1.84 (95 per cent confidence interval (c.i.) 1.11 to 3.04), P = 0.01). In particular, more headaches occurred with GTN (17 of 29 patients) than with DTZ (eight of 31) (RR 2.06 (95 per cent c.i. 1.18 to 3.59), P = 0.01). There were no significant differences in healing and symptomatic improvement rates between patients receiving GTN (25 of 29) and DTZ (24 of 31). DTZ cream caused substantially fewer headaches than GTN ointment. There was no significant difference in the healing or improvement of chronic anal fissure between the treatments. DTZ may be the preferred first-line treatment for chronic anal fissure.

Blurring of the vessels of the interhemispheric fissure in multislice CT angiography: a sign of meningeal carcinomatosis

International Nuclear Information System (INIS)

Ertl-Wagner, Birgit B.; Hoffmann, Ralf-Thorsten; Herrmann, Karin; Reiser, Maximilian F.; Bruening, Roland; Dichgans, Martin

2004-01-01

Meningeal carcinomatosis remains a challenging diagnosis to make, with both cerebrospinal fluid (CSF) analysis and radiological methods having a limited sensitivity. We aimed at describing a possible diagnostic sign of multislice CT angiography (MS-CTA) in the diagnosis of meningeal carcinomatosis. Upon retrospective analysis of MSCT angiographies of the brain, a conspicuous sign of the vessels of the interhemispheric fissure was noted in five patients. Cranial MSCT angiographies were performed with a standardized protocol (120 kV, 200 mA s, collimation of 4 x 1 mm, table feed per rotation 4 mm). We injected 120 ml of nonionic contrast medium as a bolus, and data acquisition was started after a fixed delay of 35 s. In order to elucidate the finding, correlation with clinical follow-up and/or CSF findings was performed for all patients. In five patients there was a blurring, an increased number, and a pathologic configuration of the vessels of the interhemispheric fissure. All five patients with this sign had clinical signs and symptoms of meningeal carcinomatosis. Three patients had positive CSF cytology, one further patient had follow-up spinal MRI 6 weeks later demonstrating meningeal carcinomatosis. One patient declined lumbar puncture. MS-CTA has the capacity to demonstrate a pathologic configuration of the vessels of the interhemispheric fissure in patients with meningeal carcinomatosis. This sign may serve as an indicator of meningeal carcinomatosis and should raise the suspicion of this disease entity. (orig.)

Endosonographic and manometric evaluation of internal anal sphincter in patients with chronic anal fissure and its correlation with clinical outcome after topical glyceryl trinitrate therapy.

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Pascual, Marta; Pera, Miguel; Courtier, Ricard; Gil, Mariá José; Parés, David; Puig, Sonia; Andreu, Montserrat; Grande, Luis

2007-08-01

Anorectal pressure studies have demonstrated internal anal sphincter (IAS) hypertonia in patients with chronic anal fissure. It is unknown however, if these changes in IAS function are associated with any abnormality in sphincter morphology. The first aim was to investigate the clinical characteristics and the manometric and endosonographic findings of the IAS in a cohort of patients with chronic anal fissure. The second aim was to investigate the association between these findings and the outcome with topical Glyceryl trinitrate (GTN) therapy. All patients who presented with chronic anal fissure from November 1999 to May 2004 were included after failure of conservative therapy. Anorectal manometry and anal endosonography were performed before treatment with 0.2% GTN ointment twice daily was initiated. Patients were evaluated after 8 weeks. One hundred and twenty-four patients (66 women, mean age, 45.2 +/- 14.8 years) were included. Hypertonia of the IAS was found in 84 (68%) patients. The mean maximum IAS thickness was 3.6 +/- 0.76 mm (1.6-5.5). An abnormally thick IAS, adjusted by age, was observed in 113 (91.1%) patients. We found no correlation between resting pressure and IAS thickness (r = 0.074; p = 0.41). At 8 weeks, 52 patients (42%) had healed with complete symptoms resolution. No statistically significant differences were observed when clinical features and manometric and endosonographic findings were compared between healing and no-healing fissures. The majority of patients with chronic anal fissure present an abnormally thick IAS. Clinical, manometric and endosonographic features had no association with outcome after GTN treatment.

Capillary Discourses, Fissure Points, and Tacitly Confessing the Self: Foucault's Later Work and Educational Research

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Worthman, Christopher; Troiano, Beverly

2016-01-01

This article draws on Foucault's later work to consider in an exploratory but specific way how that work can inform educational research. It introduces the concepts of "capillary discourses" and "fissure points" to show, by way of example, how a regime of truth such as neoliberalism shapes lifelong learning theory, the pedagogy…

Open versus closed lateral internal anal sphincterotomy in the management of chronic anal fissures: A prospective randomized study

Directory of Open Access Journals (Sweden)

Vivek Gupta

2014-10-01

Conclusion: Closed lateral internal sphincterotomy is the treatment of choice for chronic fissures as it is effective, safe, less expensive, and associated with a lower rate of complications than the open sphincterotomy technique.

Prevalence of Dental Caries and Fissure Sealants in a Portuguese Sample of Adolescents

Science.gov (United States)

Veiga, Nélio J.; Pereira, Carlos M.; Ferreira, Paula C.; Correia, Ilidio J.

2015-01-01

Introduction The aims of this study were to assess the prevalence of dental caries and the DMFT index, as well as the distribution pattern of pit and fissure sealants on permanent teeth in a Portuguese sample of adolescents, and to assess whether the existing usage of sealants and socio-demographic factors are correlated to caries prevalence on the examined sample. Materials and Methods A cross-sectional study was designed with a sample of 447 adolescents aged 12 to 18 years old, attending a public school in Sátão, Portugal. A self-administered questionnaire with questions about oral health behaviours and socio-economic status was answered by adolescents in the classroom. Clinical examination of oral health status and assessment of fissure sealants were accomplished by only one trained member of the research team. Results We obtained a DMFT index of 3.32 (2.92), which indicates a moderate level of prevalence of dental caries. When considering a DMFT = 0, we found significant statistical differences between the parents´ level of education (≤ 4th grade = 26.3 vs 5th–12th grade = 18.8 vs Portuguese adolescents. The establishment of a more targeted preventive program with better and more effective oral health education is essential, having into account socio-demographic aspects. PMID:25803849

[Evaluation of the effect of one-step self etching adhesives applied in pit and fissure sealing].

Science.gov (United States)

Su, Hong-Ru; Xu, Pei-Cheng; Qian, Wen-Hao

2016-06-01

To observe the effect of three one-step self etching adhesive systems used in fit and fissure sealant and explore the feasibility of application in caries prevention in school. Seven hundred and twenty completely erupted mandibular first molars in 360 children aged 7 to 9 years old were chosen. The split-mouth design was used to select one side as the experimental group, divided into A1(Easy One Adper), B1(Adper Easy One), and C1(iBond SE).The contra lateral teeth served as A2,B2 and C2 groups (phosphoric acid). The retention and caries status were regularly reviewed .The clinical effect of the two groups was compared using SPSS19.0 software package for Chi - square test. At 3 and 6 months, pit and fissure sealant retention rate in A1 and A2, B1 and B2,C1 and C2 group had no significant difference. At 12 months, sealant retention in A1 and B1 group was significantly lower than A2 and B2 group (P0.05). At 24 months, sealant retention rate in A1, B1 and C1 group was significantly lower than A2, B2 and C2 group (P0.05). The clinical anticariogenic effect of three kinds of one-step etching adhesives and phosphoric acid etching sealant was similar .One-step self etching adhesive system was recommended for pit and fissure sealant to improve the students' oral health. The long-term retention rate of one-step self etching adhesive system was lower than the phosphoric acid method to long term observation is needed.

Fissure sealants in caries prevention:a practice-based study using survival analysis

OpenAIRE

Leskinen, K. (Kaja)

2010-01-01

Abstract The purpose of this study was to analyse the effectiveness and cost of fissure sealant treatment in preventing dental caries in children in a practice-based research network using survival analysis. The survival times of first permanent molars in children were analysed in three countries: in Finland (age cohorts 1970–1972 and 1980–1982), in Sweden (1980–1982) and in Greece (1980–1982), and additionally at two municipal health centres in Finland (age cohorts 1988–1990 in Kemi...

Superior orbital fissure syndrome in herpes zoster ophthalmicus.

LENUS (Irish Health Repository)

Kirwan, R P

2012-02-01

AIM: To report a case of superior orbital fissure syndrome (SOFS) in a patient with herpes zoster ophthalmicus (HZO). MATERIALS AND METHODS: A case report. RESULTS: A 71-year-old male with HZO presented acutely to accident and emergency complaining of right vision loss, double vision and drowsiness. The right visual acuity was counting fingers. There was no relative afferent pupillary defect. He had interstitial keratitis, ptosis, proptosis and total ophthalmoplaegia. The signs indicated HZO complicated by SOFS. Brain imaging and lumbar puncture confirmed the diagnosis of varicella zoster encephalitis. Systemic acyclovir and prednisolone led to recovery of visual acuity and ocular motility in addition to resolution of his proptosis and ptosis. CONCLUSION: SOFS is a rare complication of herpes zoster infection. With the appropriate treatment and follow-up, patients may be reassured that recovery of their visual acuity and ocular motility will occur.

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining.

Science.gov (United States)

Yang, Jing-Hu; Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of "cantilever beam and elastic foundation beam" was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the propagation

Physical simulation and theoretical evolution for ground fissures triggered by underground coal mining

Science.gov (United States)

Yu, Xiang; Yang, Yi; Yang, Zeng-Qiang

2018-01-01

Underground coal mining activities are prone to cause movement and breakage in geological strata and also lead to mining subsidence and even ground fissures. Along the direction working panel advancing, ground fissures may occur in roof in front and/or behind working panel. However, the investigations of previous similarity tests in lab only emphasize on the region behind working panel. By improving strata material property in construction and mounting artificial pressure devices, two physical simulation tests were conducted and successfully investigated the simulated results. Then, the mechanical model of “cantilever beam and elastic foundation beam” was proposed to calculate the stress distribution and the crack initiation angle in overlying strata and it well explains the mechanisms of ground fissures generation and propagation. Results show that, the maximum internal force in roof always occurred in front of working panel. However, because the void space in gob due to excavation is large enough to cause the bend and rotation of roof strata, compare to the triaxially compressed region in front of working panel, the roof always broke off at some positions above gob since the stress concentration resulting from such bend and rotation of strata could easily reach the limit strength of strata rocks. Also, the length of cantilever beam changed dynamically as respect to the panel advancing and the breakage intervals. Thus, the breakage position where the internal force first reached the limit tensile strength is not fixed and there will be two different kinds of relative positions between the crack initiation point and the working panel. The crack initiation direction is always perpendicular to the internal force, and the crack propagation direction is affected by the initiation angle, overburden-separation degree and the position of the hydraulic shields. If there is no overburden-separation or less, the roofs will break off as a composite beam and the

Journal of Earth System Science | Indian Academy of Sciences

Indian Academy of Sciences (India)

The artificial recharge is a technique of aquifer conservation for land subsidence. But in this article, the phenomenon of land subsidence and the resulting cracks and fissures at the study area are formed in recharge ponds. This is a new phenomenon and in this research the geometrical properties of the fissures of recharge ...

Analysis of radionuclide transport through fissured porous media with a perturbation method

Energy Technology Data Exchange (ETDEWEB)

Banat, M [JGC Corp., Tokyo (Japan)

1995-04-01

This paper presents a specific procedure for obtaining solutions for the transport of radionuclides in a fissured porous media. The concentration profiles are deduced for a wide range of Peclet numbers using a perturbation method with a multiscale of time. Results show clearly that because of an increase of longitudinal dispersion, the radionuclide moves faster with respect to the case of zero dispersion (i.e. an infinite Peclet number). The main purpose of this paper is to demonstrate the practical advantage of the present calculation method with respect to the classical numerical and analytical methods used for radionuclide transport. (author).

Retention of a resin-based sealant and a glass ionomer used as a fissure sealant: A comparative clinical study

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Subramaniam P

2008-09-01

Full Text Available Sealing occlusal pits and fissures with resin-based sealants is a proven method of preventing occlusal caries. Retention of the sealant is very essential for its efficiency. This study evaluated the retention of glass ionomer used as a fissure sealant when compared to a self-cure resin-based sealant. One hundred and seven children between the ages of 6-9 years, with all four newly erupted permanent first molars were selected. Two permanent first molars on one side of the mouth were sealed with Delton, a resin-based sealant, and the contralateral two permanent first molars were sealed with Fuji VII glass ionomer cement. Evaluation of sealant retention was performed at regular intervals over 12 months, using Simonsen′s criteria. At the end of the study period, the retention of the resin sealant was seen to be superior to that of the glass ionomer sealant.

Permeability of fissured rock - an experimental study with special regard to the water injection test

International Nuclear Information System (INIS)

Schneider, H.J.

1987-01-01

The permeability to water of fissured rock is one of the most important design parameters for many underground projects, such as, e.g. the final deposition of radioactive waste. Because the conventional water injection test according to LUGEON for the calculation of permeability to water is associated with a high degree of uncertainty, new test equipment was developed. This equipment works on the principle of the water injection tracer test and multi-level measurements, enabling detailed measurement of the flow process at injection site and in the rock. The tests were carried out in Bunter sandstone and granite. The LUGEON test concept was varied in short-term and long-term tests at identical geological boundary conditions, and with test control at constant pressure on the one hand and at constant injection volume on the other. The test results show that non-steady-state flow occurs with short injection times, whereby the range is limited to the local rock at injection site. An increasing in injection time can lead to an increase in range by a number of factors as well as to steady-state flow conditions. The permeability of the rock types investigated is inhomgeneous and anistropic as a result of the fissured structure. (orig./HP) With 114 figs., 4 tabs [de

Long-term outcomes of Botulinum toxin in the treatment of chronic anal fissure: 5 years of follow-up.

Science.gov (United States)

Barbeiro, Sandra; Atalaia-Martins, Catarina; Marcos, Pedro; Gonçalves, Cláudia; Canhoto, Manuela; Arroja, Bruno; Silva, Filipe; Cotrim, Isabel; Eliseu, Liliana; Santos, Antonieta; Vasconcelos, Helena

2017-03-01

Chronic anal fissure is a frequent and disabling disease, often affecting young adults. Botulinum toxin and lateral internal sphincterotomy are the main therapeutic options for refractory cases. Botulinum toxin is minimally invasive and safer compared with surgery, which carries a difficult post-operative recovery and fecal incontinence risk. The long-term efficacy of Botulinum toxin is not well known. The aim of this study was to evaluate the long-term efficacy and safety of Botulinum toxin in the treatment of chronic anal fissure. This was a retrospective study at a single center, including patients treated with Botulinum toxin from 2005 to 2010, followed over at least a period of 5 years. All patients were treated with injection of 25U of Botulinum toxin in the intersphincteric groove. The response was registered as complete, partial, refractory and relapse. Botulinum toxin was administered to 126 patients, 69.8% ( n  = 88) were followed over a period of 5 years. After 3 months, 46.6% ( n  = 41) had complete response, 23.9% ( n  = 21) had partial response and 29.5% ( n  = 26) were refractory. Relapse was observed in 1.2% ( n  = 1) at 6 months, 11.4% ( n  = 10) at 1 year, 2.3% ( n  = 2) at 3 years; no relapse at 5 years. The overall success rate was 64.8% at 5 years of follow-up. Botulinum toxin was well tolerated by all patients and there were no complications. The use of Botulinum toxin to treat patients with chronic anal fissure was safe and effective in long-term follow-up.

Modeling of the pollutant transport in fissured-porous media under consideration of colloids using the transport codes FRAME and COFRAME; Modellierung des Schadstofftransports in geklueftet-poroesen Medien unter Beruecksichtigung von Kolloiden mit den Transportprogrammen FRAME und COFRAME

Energy Technology Data Exchange (ETDEWEB)

Reiche, Tatiana; Noseck, Ulrich; Wolf, Jens Wilhelm

2014-05-15

For the long-term safety analysis of final nuclear waste repositories the transport of pollutants from the repository into the biosphere three mostly independent subsystems are considered: the near field, the geosphere and the biosphere. Normally rocks include fissures or other disturbances. Porous materials in the rock matrix have usually a high water content and acts as storage for pollutants due to sorption and diffusion processes. The aim of the project is the development of calculation modules for the code RepoTREND that simulate the pollutant transport in saturated fissured-porous media taking into account the effect of colloids. FRAME describes the pollutant dispersion in a fissured-porous medium and COFRAME the colloid influenced transport in a fissured-porous medium.

Caries progression in non-cavitated fissures after infiltrant application: a 3-year follow-up of a randomized controlled clinical trial

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Camillo ANAUATE-NETTO

Full Text Available Abstract Objectives To evaluate the efficacy of a conservative treatment to prevent the progression of caries using an infiltrant on non-cavitated pit and fissures. Material and Methods This controlled clinical trial selected 23 volunteers with clinically and radiographically non-cavitated occlusal caries among patients presenting a “rather low” to “very high” caries risk. Eighty-six teeth were randomly divided into two experimental groups: teeth receiving a commercial pit-and-fissure sealant (Alpha Seal-DFL and contralateral teeth receiving Icon infiltrant (DMG. Caries progression was monitored by clinical (laser fluorescence caries detection and radiographic examination at 12-month intervals over a period of 3 years of monitored caries progression. Probing the sealing materials to detect areas of retention was also used to evaluate marginal integrity. Results Statistical analysis showed no difference in caries progression using laser fluorescence caries detection when both materials were compared, regardless of the evaluation times (p>0.05. No significance was observed when the marginal sealant integrity of both materials was compared, regardless of the evaluation time (p0.05. SEM analysis exhibited a more homogeneous sealing for the infiltrant than obtained by the sealant. Conclusions The infiltrant was effective to prevent the caries progression in non-cavitated pit-and-fissures after 3 years of clinical evaluation, comparable with the conventional sealant. The infiltrant also presented better results in terms of caries progression at the 3-year evaluation time using the radiographic analysis.

Caries progression in non-cavitated fissures after infiltrant application: a 3-year follow-up of a randomized controlled clinical trial

Science.gov (United States)

ANAUATE-NETTO, Camillo; BORELLI, Laurindo; AMORE, Ricardo; DI HIPÓLITO, Vinicius; D’ALPINO, Paulo Henrique Perlatti

2017-01-01

Abstract Objectives To evaluate the efficacy of a conservative treatment to prevent the progression of caries using an infiltrant on non-cavitated pit and fissures. Material and Methods This controlled clinical trial selected 23 volunteers with clinically and radiographically non-cavitated occlusal caries among patients presenting a “rather low” to “very high” caries risk. Eighty-six teeth were randomly divided into two experimental groups: teeth receiving a commercial pit-and-fissure sealant (Alpha Seal-DFL) and contralateral teeth receiving Icon infiltrant (DMG). Caries progression was monitored by clinical (laser fluorescence caries detection) and radiographic examination at 12-month intervals over a period of 3 years of monitored caries progression. Probing the sealing materials to detect areas of retention was also used to evaluate marginal integrity. Results Statistical analysis showed no difference in caries progression using laser fluorescence caries detection when both materials were compared, regardless of the evaluation times (p>0.05). No significance was observed when the marginal sealant integrity of both materials was compared, regardless of the evaluation time (p0.05). SEM analysis exhibited a more homogeneous sealing for the infiltrant than obtained by the sealant. Conclusions The infiltrant was effective to prevent the caries progression in non-cavitated pit-and-fissures after 3 years of clinical evaluation, comparable with the conventional sealant. The infiltrant also presented better results in terms of caries progression at the 3-year evaluation time using the radiographic analysis. PMID:28877284

Applying psychological theories to evidence-based clinical practice: identifying factors predictive of placing preventive fissure sealants.

Science.gov (United States)

Bonetti, Debbie; Johnston, Marie; Clarkson, Jan E; Grimshaw, Jeremy; Pitts, Nigel B; Eccles, Martin; Steen, Nick; Thomas, Ruth; Maclennan, Graeme; Glidewell, Liz; Walker, Anne

2010-04-08

Psychological models are used to understand and predict behaviour in a wide range of settings, but have not been consistently applied to health professional behaviours, and the contribution of differing theories is not clear. This study explored the usefulness of a range of models to predict an evidence-based behaviour -- the placing of fissure sealants. Measures were collected by postal questionnaire from a random sample of general dental practitioners (GDPs) in Scotland. Outcomes were behavioural simulation (scenario decision-making), and behavioural intention. Predictor variables were from the Theory of Planned Behaviour (TPB), Social Cognitive Theory (SCT), Common Sense Self-regulation Model (CS-SRM), Operant Learning Theory (OLT), Implementation Intention (II), Stage Model, and knowledge (a non-theoretical construct). Multiple regression analysis was used to examine the predictive value of each theoretical model individually. Significant constructs from all theories were then entered into a 'cross theory' stepwise regression analysis to investigate their combined predictive value. Behavioural simulation - theory level variance explained was: TPB 31%; SCT 29%; II 7%; OLT 30%. Neither CS-SRM nor stage explained significant variance. In the cross theory analysis, habit (OLT), timeline acute (CS-SRM), and outcome expectancy (SCT) entered the equation, together explaining 38% of the variance. Behavioural intention - theory level variance explained was: TPB 30%; SCT 24%; OLT 58%, CS-SRM 27%. GDPs in the action stage had significantly higher intention to place fissure sealants. In the cross theory analysis, habit (OLT) and attitude (TPB) entered the equation, together explaining 68% of the variance in intention. The study provides evidence that psychological models can be useful in understanding and predicting clinical behaviour. Taking a theory-based approach enables the creation of a replicable methodology for identifying factors that may predict clinical behaviour

Comparison of microleakage between flowable nanocomposite, flowable Composite and Conventional sealant in fissure sealant therapy of the permanent teeth: an in- vitro study

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Sara Maleki Kambakhsh

2016-11-01

Full Text Available Background and Aim: Novel dental materials including nanocomposites have been introduced in recent years. It is claimed that they have superior properties such as high esthetic., low wear, increased filler content resulting in better mechanical properties, and releasing ions i.e. fluoride and amorphous calcium phosphate that are important for enamel remineralization. Considering these features, if they have retention and microleakage rates comparable with conventional sealants, these materials can be appropriate alternatives to conventional resin sealants in future. The current study aimed at comparing . microleakage of a flowable nanocomposite, a flowable composite , and a conventional sealant in fissure sealant therapy of the permanent teeth. Materials and Methods: First of all ,42 extracted sound human maxillary first premolars were collected and were randomly divided into 3 equal groups. Then the teeth were embedded in self-cure acrylic resin. Occlusal fissures of the samples were cleaned using explorer, enameloplasty with ¼ round diamond bur and water/air spray was done. The prepared surfaces were etched using 36% phosphoric acid gel for 15s, rinsed and dried. Bonding agent was placed in the pits and fissures, cured for 10s after thinning with air. In the first, second , and the third group conventional sealant, flowable composite , and flowable nanocomposite were placed, respectively; and light cured for 40s. The samples were thermocycled (1000 cycles between 5-55ºC and then immersed in 2% basic Fuchsine solution for 24hs. They were then cut bucculingually and microleakage evaluation was done using stereomicroscope. The obtained data was analyzed using Kruskal wallis tests. Results: There was no significant difference in microleakage rate of the study groups. (P>0.05. Conclusion: Considering the condition of the study, it can be concluded that flowable composite and flowable nanocomposite can be used as suitable alternatives to

Frequency of remnants of sealants left behind in pits and fissures of occlusal surfaces after 2 and 3 years.

NARCIS (Netherlands)

Hu, X.; Zhang, W.; Fan, M.; Mulder, J.; Frencken, J.E.F.M.

2017-01-01

OBJECTIVES: The null-hypothesis tested was that there was no difference in the frequency of remnants of high-viscosity glass-ionomer sealants left behind in pits and fissures of occlusal surfaces of first permanent molars and that of resin composite and glass-carbomer sealants. MATERIALS AND

A clinical trial to evaluate the retention of a silver cermet-ionomer cement used as a fissure sealant.

Science.gov (United States)

Mills, R W; Ball, I A

1993-01-01

A randomized clinical trial was under-taken to compare the retention of a silver cermet-ionomer cement, Ketac Silver, with a conventional, autopolymerizing BIS-GMA resin sealant, Delton, using matched pairs of fissure sites within each subject's mouth. One hundred twenty matched contralateral pairs of fissure sites in first and second permanent molars of 53 school children were sealed with the two materials. The choice of site and material was selected at random. The ages of the children ranged from five to 16 years; first permanent molars were sealed in the five- to 10-year age group, and second permanent molars in the 11- to 16-year age group. Sealants were assessed as present, partly present, or absent at 6, 12, and 24 months. The number of pairs of sites available for reassessment declined from 102 at six months to 59 at 24 months as patients were lost to the study. Retention rates were higher for the Ketac Silver sealants at all three inspection intervals (P cermet cement was better retained than conventional resin sealants in younger children.

Origins of feeding arteries of hepatocellular carcinoma located near the umbilical fissure of the left hepatic lobe: angiographic evaluation.

Science.gov (United States)

Miyayama, Shiro; Yamashiro, Masashi; Shibata, Yoshihiro; Hashimoto, Masahiro; Yoshida, Miki; Tsuji, Kazunobu; Toshima, Fumihito; Matsui, Osamu

2012-12-01

To analyze the origins of the feeding arteries of hepatocellular carcinomas (HCCs) near the umbilical fissure of the left hepatic lobe. Twenty-eight HCCs with a mean ± SD tumor diameter of 3.4 ± 1.0 cm (range 1-4.4 cm) in contact with the right or left side of the umbilical fissure were treated by superselective transcatheter arterial chemoembolization (TACE). The origins of the tumor-feeding arteries were analyzed with arteriograms and computed tomography or cone-beam computed tomography images obtained during and 1 week after TACE. Twenty-one HCC lesions were located in segment 3 and seven were located in segment 4. Of 21 tumors in segment 3, 13 (61.9%) were supplied by the lateral inferior subsegmental artery (A3), three (14.3%) by the medial subsegmental artery (A4), three (14.3%) by both A4 and A3, one (4.8%) by a branch arising from the left lateral hepatic artery, and one (4.8%) by a branch of the right gastric artery. In particular, all tumor-feeding branches arising from A4 were the first branch of A4. Of seven tumors in segment 4, four (57.1%) were supplied by A4 and three (42.9%) by A3. In particular, all tumor-feeding branches arising from A3 were the first branch of A3. This study demonstrates crossover blood supply to HCC lesions located near the umbilical fissure, in addition to direct feeding from a separate branch. In particular, the first branch of the opposite subsegmental artery may feed tumors when crossover blood supply is present.

Origins of Feeding Arteries of Hepatocellular Carcinoma Located Near the Umbilical Fissure of the Left Hepatic Lobe: Angiographic Evaluation

Energy Technology Data Exchange (ETDEWEB)

Miyayama, Shiro, E-mail: s-miyayama@fukui.saiseikai.or.jp; Yamashiro, Masashi; Shibata, Yoshihiro; Hashimoto, Masahiro; Yoshida, Miki; Tsuji, Kazunobu; Toshima, Fumihito [Fukuiken Saiseikai Hospital, Department of Diagnostic Radiology (Japan); Matsui, Osamu [Kanazawa University Graduate School of Medical Science, Department of Radiology (Japan)

2012-12-15

Purpose: To analyze the origins of the feeding arteries of hepatocellular carcinomas (HCCs) near the umbilical fissure of the left hepatic lobe. Methods: Twenty-eight HCCs with a mean {+-} SD tumor diameter of 3.4 {+-} 1.0 cm (range 1-4.4 cm) in contact with the right or left side of the umbilical fissure were treated by superselective transcatheter arterial chemoembolization (TACE). The origins of the tumor-feeding arteries were analyzed with arteriograms and computed tomography or cone-beam computed tomography images obtained during and 1 week after TACE.ResultsTwenty-one HCC lesions were located in segment 3 and seven were located in segment 4. Of 21 tumors in segment 3, 13 (61.9%) were supplied by the lateral inferior subsegmental artery (A3), three (14.3%) by the medial subsegmental artery (A4), three (14.3%) by both A4 and A3, one (4.8%) by a branch arising from the left lateral hepatic artery, and one (4.8%) by a branch of the right gastric artery. In particular, all tumor-feeding branches arising from A4 were the first branch of A4. Of seven tumors in segment 4, four (57.1%) were supplied by A4 and three (42.9%) by A3. In particular, all tumor-feeding branches arising from A3 were the first branch of A3. Conclusion: This study demonstrates crossover blood supply to HCC lesions located near the umbilical fissure, in addition to direct feeding from a separate branch. In particular, the first branch of the opposite subsegmental artery may feed tumors when crossover blood supply is present.

The Safety and Efficacy of a Mixture of Honey, Olive Oil, and Beeswax for the Management of Hemorrhoids and Anal Fissure: A Pilot Study

Directory of Open Access Journals (Sweden)

Noori S. Al-Waili

2006-01-01

Full Text Available We have found that a mixture of honey, olive oil, and beeswax was effective for treatment of diaper dermatitis, psoriasis, eczema, and skin fungal infection. The mixture has antibacterial properties. A prospective pilot study was conducted to evaluate the therapeutic effect of topical application of the mixture on patients with anal fissure or hemorrhoids.Fifteen consecutive patients, 13 males and 2 females, median age 45 years (range: 28–70, who presented with anal fissure (5 patients or first- to third-degree hemorrhoids (4 with first degree, 4 with second degree, and 2 with third degree, were treated with a 12-h application of a natural mixture containing honey, olive oil, and beeswax in ratio of 1:1:1(v/v/v. Bleeding, itching, edema, and erythema were measured using a scoring method: 0 = none, 1 = mild, 2 = moderate, 3 = severe, and 4 = very severe. The pain score was checked using a visual analog scale (minimum = 0, maximum = 10. Efficacy of treatment was assessed by comparing the symptoms' score before and after treatment; at weekly intervals for a maximum of 4 weeks. The patients were observed for evidence of any adverse effect such as appearance of new signs and symptoms, or worsening of the existing symptoms. The honey mixture significantly reduced bleeding and relieved itching in patients with hemorrhoids. Patients with anal fissure showed significant reduction in pain, bleeding, and itching after the treatment. No side effect was reported with use of the mixture. We conclude that a mixture of honey, olive oil, and beeswax is safe and clinically effective in the treatment of hemorrhoids and anal fissure, which paves the way for further randomized double blind studies.

Prevalence of the types of the petrotympanic fissure in the temporomandibular joint dysfunction

International Nuclear Information System (INIS)

Cakur, Binali; Sumbullu, Muhammed Akif; Durna, Dogan; Akgul, Hayati Murat

2011-01-01

Background Petrotympanic fissure (PTF) is a fissure in the temporal bone that runs from the temporomandibular joint (TMJ) to the tympanic cavity (TC). In PTF, the discomallear ligament (DML) connects the malleus in the tympanic cavity and the articular disc and capsule of the temporomandibular joint. PTF with the DML is a possible cause of aural symptoms related to temporomandibular joint dysfunction (TMD). Purpose To investigate the prevalence of different types of PTF in TMD using dental volumetric tomography (DVT) and determine whether PTF type correlates with age. Material and Methods DVT scans in the sagittal planes of PTFs of 134 patients with TMD were examined for the types of PTF present. Three main PTF types were described: wide, tunnel-shaped structure (type 1); tunnel-shaped structure that is wide open in the PTF entrance to the mandibular fossa and gradually thins out in the tympanic cavity (type 2), tunnel-shaped structure that is wide open in the entrance of the mandibular fossa, with a middle region with a flat-shaped tunnel structure and a narrow exit in the tympanic cavity (type 3). Results In DVT scans, PTF types 1, 2 and 3 were seen in 67.2%, 1.5%, and 31.3% of cases, respectively. We found no significant relationship between age or gender and PTF type. Conclusion The low percentage of type 2 PTF and high percentage of type 1 PTF must be taken into consideration during pre-surgical planning related to TMD. However, future well-designed clinical studies involving larger numbers of subjects will be necessary to confirm the findings of this study

Prevalence of the types of the petrotympanic fissure in the temporomandibular joint dysfunction

Energy Technology Data Exchange (ETDEWEB)

Cakur, Binali; Sumbullu, Muhammed Akif; Durna, Dogan; Akgul, Hayati Murat (Dept. of Oral Diagnosis and Oral Radiology, Faculty of Dentistry, Ataturk Univ., Erzurum (Turkey)), email: bcakur@atauni.edu.tr

2011-06-15

Background Petrotympanic fissure (PTF) is a fissure in the temporal bone that runs from the temporomandibular joint (TMJ) to the tympanic cavity (TC). In PTF, the discomallear ligament (DML) connects the malleus in the tympanic cavity and the articular disc and capsule of the temporomandibular joint. PTF with the DML is a possible cause of aural symptoms related to temporomandibular joint dysfunction (TMD). Purpose To investigate the prevalence of different types of PTF in TMD using dental volumetric tomography (DVT) and determine whether PTF type correlates with age. Material and Methods DVT scans in the sagittal planes of PTFs of 134 patients with TMD were examined for the types of PTF present. Three main PTF types were described: wide, tunnel-shaped structure (type 1); tunnel-shaped structure that is wide open in the PTF entrance to the mandibular fossa and gradually thins out in the tympanic cavity (type 2), tunnel-shaped structure that is wide open in the entrance of the mandibular fossa, with a middle region with a flat-shaped tunnel structure and a narrow exit in the tympanic cavity (type 3). Results In DVT scans, PTF types 1, 2 and 3 were seen in 67.2%, 1.5%, and 31.3% of cases, respectively. We found no significant relationship between age or gender and PTF type. Conclusion The low percentage of type 2 PTF and high percentage of type 1 PTF must be taken into consideration during pre-surgical planning related to TMD. However, future well-designed clinical studies involving larger numbers of subjects will be necessary to confirm the findings of this study

Clinical and manometric evaluation of women with chronic anal fissure before and after internal subcutaneous lateral sphincterotomy

Directory of Open Access Journals (Sweden)

Silvana Marques e Silva

2012-06-01

Full Text Available OBJECTIVE: To evaluate clinical and manometric parameters of chronic anal fissure females undergoing lateral internal sphincterotomy (LIS. METHODS: A total of eight women with chronic anal fissure who underwent LIS were included in this study. The preoperative assessment was performed one week before surgery and included general and anorectal examination, anorectal manometry, and Jorge Wexner questionnaire. The post operative follow up was made every 15 days until complete healing. Jorge Wexner questionnaires and anorectal manometry were repeated at 1 month and 3 months after the surgery. Time to healing, manometric changes and complications were assessed. RESULTS: All patients had preoperative increased anal resting pressure. The resting pressures and anal canal length were significantly decreased 3 months after surgery. Patients' complaints of itching and bleeding were also reduced. Fissures healed in 7 patients and median healing time was 45 days. No complications were observed due to the procedure. One patient had transient incontinence to flatus. CONCLUSION: Lateral internal sphincterotomy provided clinical improvement and reduced resting pressure of the internal anal sphincter in women with chronic anal fissure.OBJETIVO: Avaliar a evolução clínica e manométrica de mulheres com fissura anal crônica submetidas à esfincterotomia lateral interna subcutânea. MÉTODOS: Estudo prospectivo com oito pacientes. A avaliação inicial foi realizada por meio de questionários, exame físico e manometria anorretal na semana anterior ao procedimento cirúrgico. Durante o período pós-operatório, as pacientes foram avaliadas clinicamente a cada 15 dias, até a cicatrização completa. Os questionários e a manometria anorretal foram repetidos 1 mês e 3 meses após a operação. Foi avaliado o tempo para cicatrização da fissura, as alterações manométricas e as complicações decorrentes do procedimento. RESULTADOS: Todas as pacientes

Applying psychological theories to evidence-based clinical practice: identifying factors predictive of placing preventive fissure sealants

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Maclennan Graeme

2010-04-01

Full Text Available Abstract Background Psychological models are used to understand and predict behaviour in a wide range of settings, but have not been consistently applied to health professional behaviours, and the contribution of differing theories is not clear. This study explored the usefulness of a range of models to predict an evidence-based behaviour -- the placing of fissure sealants. Methods Measures were collected by postal questionnaire from a random sample of general dental practitioners (GDPs in Scotland. Outcomes were behavioural simulation (scenario decision-making, and behavioural intention. Predictor variables were from the Theory of Planned Behaviour (TPB, Social Cognitive Theory (SCT, Common Sense Self-regulation Model (CS-SRM, Operant Learning Theory (OLT, Implementation Intention (II, Stage Model, and knowledge (a non-theoretical construct. Multiple regression analysis was used to examine the predictive value of each theoretical model individually. Significant constructs from all theories were then entered into a 'cross theory' stepwise regression analysis to investigate their combined predictive value Results Behavioural simulation - theory level variance explained was: TPB 31%; SCT 29%; II 7%; OLT 30%. Neither CS-SRM nor stage explained significant variance. In the cross theory analysis, habit (OLT, timeline acute (CS-SRM, and outcome expectancy (SCT entered the equation, together explaining 38% of the variance. Behavioural intention - theory level variance explained was: TPB 30%; SCT 24%; OLT 58%, CS-SRM 27%. GDPs in the action stage had significantly higher intention to place fissure sealants. In the cross theory analysis, habit (OLT and attitude (TPB entered the equation, together explaining 68% of the variance in intention. Summary The study provides evidence that psychological models can be useful in understanding and predicting clinical behaviour. Taking a theory-based approach enables the creation of a replicable methodology for

A Comparative Evaluation of the Effect of Bonding Agent on the Tensile Bond Strength of Two Pit and Fissure Sealants Using Invasive and Non-invasive Techniques: An in-vitro Study.

Science.gov (United States)

Singh, Shamsher; Adlakha, Vivek; Babaji, Prashant; Chandna, Preetika; Thomas, Abi M; Chopra, Saroj

2013-10-01

Newer technologies and the development of pit and fissure sealants have shifted the treatment philosophy from 'drill and fill' to that of 'seal and heal'. The purpose of this in-vitro study was to evaluate the effects of bonding agents on the tensile bond strengths of two pit and fissure sealants by using invasive and non-invasive techniques. One hundred and twenty bicuspids were collected and teeth were divided into two groups: Group-I (Clinpro) and Group-II (Conseal f) with 60 teeth in each group. For evaluating tensile bond strengths, occlusal surfaces of all the teeth were flattened by reducing buccal and lingual cusps without disturbing fissures. Standardised polyvinyl tube was bonded to occlusal surfaces with respective materials. Sealants were applied, with or without bonding agents, in increments and they were light cured. Tensile bond strengths were determined by using Universal Testing Machine. Data were then statistically analysed by using Student t-test for comparison. A statistically significant difference was found in tensile bond strength in invasive with bonding agent group than in non-invasive with bonding agent group. This study revealed that invasive techniques increase the tensile bond strengths of sealants as compared to non- invasive techniques and that the use of a bonding agent as an intermediate layer between the tooth and fissure sealant is beneficial for increasing the bond strength.

Detection of occlusal caries with impedance spectroscopy and laser fluorescence before and after placement of fissure sealants: An in vitro study

DEFF Research Database (Denmark)

Mortensen, Diana; Ekstrand, Kim; Twetman, Svante

2016-01-01

, the DIAGNOdent pen and ICDAS at baseline, after bleaching, etching and placement of a clear fissure sealant. A digital radiograph was exposed at baseline. After the assessments, the actual lesion depth was histologically determined.  Results : Bleaching did not affect the readings but significantly higher ACIS...

Isosorbide dinitrate ointment vs botulinum toxin A (Dysport®) as the primary treatment for chronic anal fissure: a randomized multicentre study

NARCIS (Netherlands)

Berkel, A.E.M.; Rosman, C.; Koop, R.; van Duijvendijk, P.; van der Palen, Jacobus Adrianus Maria; Klaase, J.M.

2014-01-01

Aim Nitric oxide donors, such as isosorbide dinitrate ointment (ISDN), are considered as first-choice agents in the treatment of chronic anal fissure. Injection with botulinum toxin A in the internal anal sphincter is often used as a second-line therapy, although it may give better results and fewer

Comparative efficacy of nanofilled and microfilled resin-modified glass ionomer as pits and fissure sealant in permanent molar teeth

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Manzuma Akhter Zakaria

2017-05-01

Full Text Available The purpose of the present study was to compare the efficacy of nanofilled and microfilled resin- modified glass ionomer as pits and fissure sealants in permanent molar teeth. Ninety six teeth having fissure at the occlusal surface were randomly divided into two groups: Group I: Treated by nanofilled resin-modified glass ionomer sealant and Group II: Treated by microfilled resin- modified glass ionomer sealants. Clinical assessment was performed by modified Ryge´s criteria by means of retention, color match, marginal adaptation at 3, 6, and 12 months follow-up visit. Chi-square test was used for testing differences between the two groups; a value of p<0.05 was considered as statistically significant. The results revealed that at 12 months observation period, nanofilled resin-modified glass ionomer sealant showed better retention, color stability and marginal adaptation than that of microfilled resin-modified glass ionomer sealants. Furthermore, the differences between two groups in respect to marginal adaptation and color match were statistically significant (p<0.05. It can be concluded that nanofilled resin-modified glass ionomer sealant could be a better alternative to microfilled resin- modified glass ionomer sealant.

Fissures in the commercial cinematic space: Screening Taiwanese documentary blockbusters

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Hong-Chi Shiau

2016-12-01

Full Text Available This study explores the trajectory of how a new wave of documentary making has incorporated or resisted dominant social forces to create fissures in the commercial cinematic spaces. Two documentary blockbusters The Long Goodbye (2010 and Beyond Taiwan (2013 are examined to explicate how the restructuring of cinematic spaces in Taiwan has facilitated changes in documentary screening culture and spectatorships, leading to the recent documentary renaissance. This result suggests that independent filmmakers intervene and create the spaces for their documentaries, financially dependent on advance ticket sales and private sponsorship. However, relational distributive venues of documentary film within a larger public sphere are increasingly privatized and commercialized in the age of global neoliberalism. The various and creative methods applied in the exhibition of documentary blockbusters have illuminated the intersection of documentary and mainstream commercial cinema sites and practices, and have spawned associated, commercially oriented articulations. The reception study reveals that the past decade has witnessed Taiwanese audiences anxiously situate their precarious local identity against a myriad of socio-political crises: an aging and shrinking population, environmental pollution, and stagnant economy.

Sorption and diffusion of cobalt, strontium, cesium and americium in natural fissure surfaces and drill core cups studied by autoradiography, 1

International Nuclear Information System (INIS)

Pinnioja, S.; Kaemaeraeinen, E.L.; Jaakkola, T.; Siitari, M.; Muuronen, S.; Lindberg, A.

1985-06-01

A method based on autoradiography was developed to determine the diffusion of radionuclides into the rock matrix. To investigate the diffusion the samples, which has been in contact with radioactive tracer solution up to 6 months, were splitted by sawing. From the autoradiograms of the cross sections the penetration depths of radionuclides were determined and the apparent diffusion coefficient Dsup(a) calculated. The filled and unfilled natural fissure surfaces chosen to this study were bars of drilling cores and drill core cups of tonalite, mica gneiss and rapakivi granite. After contact time of 3 months the highest penetration depths of cesium were observed for natural fissure surface sample of rapakivi granite up to 2.5 mm and of mica gneiss up to 3.7 mm. For strontium the penetration depths of 6 mm and 11 mm for unfilled and filled natural fissure samples of rapakivi granite were found. Dsup(a)-values for cesium varied between 1.5 x 10 -15 and 3.2 x 10 -14 , for strontium between 3.5 x 10 -14 and 2.1 x 10 -13 m 2 /s. D-value obtained for cobalt (drill core cup sample, tonalite) was 5.4 x 10 -17 m 2 /s. 241 Am was only sorbed on the surface of the sample and thus no apparent diffusion coefficient could be calculated. Filling materials, chlorite and secondary minerals in tonalite and rapakivi granite increased diffusion into the mother rock. Radionuclides were sorbed both into the filling material and through fillers into the rock matrix. Cs and Sr penetrated though calcite filling material in mica gneiss into the mother rock. Calcite didn't influence on diffusion of radionuclides. Penetration depths of Cs and Sr were about the same for filled and unfilled samples

Fissure sealants: in vitro evaluation of abrasion wear and superficial roughness

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Vanessa Pardi

2008-06-01

Full Text Available The aim of this study was to compare the in vitro wear and superficial roughness of four materials (Delton Dyract Flow, Dentsply; Filtek Flow, Vitremer, 3M ESPE used as fissure sealant in 32 extracted human molars divided in four groups (n = 8 after abrasion with toothbrush/dentifrice. Impressions of each occlusal surface were made to analyze wear and circular specimens were prepared to analyze the roughness. Teeth and specimens were mounted in a toothbrushing machine. The replicas were observed using a SEM to determine the superficial wear. Wear: there were no statistically significant differences either between Delton and Filtek Flow or between Dyract Flow and Vitremer. Roughness: there were no statistical differences between Filtek Flow and Dyract Flow, Dyract Flow and Vitremer, Vitremer and Delton., Considering the clinical practice, if caries activity is present the use of Vitremer is suggested not only for its well known fluoride release, but it presented good roughness results.

Fractionation of rare earths elements in weathering profiles on phonolites in area of Lages, Santa Catarina, Brazil

International Nuclear Information System (INIS)

Formoso, M.L.L.; Valeton, J.; Retzmann, R.

1989-01-01

Niobium and rare earth elements are associated with alkaline intrusions, especially in sequences containing carbonatites. During deep ferralitic weathering on the Lower Tertiary peneplanation plain REE are mobilized and depleted as well in the lower saprolite as in the upper ferralite, except Cerium which shows a positive anormaly. Triangular diagrams of Ce, Nd, La represent a relative enrichment of La, whereas comparing Ce, La and Nb, the increase of Niobium is strongest with rising weathering. After intersection of the landscape into inselbergs and lowering of the aquifers a later period of mobilization and migration of the REE together with manganese, aluminium and silica took place in descending direction. Their absolute enrichment by precipitation is concentrated in fissure fillings and porespaces in the lowermost part of the profiles. Main minerals are lithiophorite and halloysite. (author) [pt

Inorganic carbon cycle in soil-rock-groundwater system in karst and fissured aquifers

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Ajda Koceli

2013-12-01

Full Text Available The paper presents a systematic analysis of the isotopic composition of carbon (δ13CCaCO3 in carbonate rocks in central Slovenia, representing karst and fissured aquifers, and share of carbon contributions from carbonate dissolution and degradation of organic matter in aquifers, calculated from the mass balance equation. 59 samples of rocks (mainly dolomites from Upper Permian to Upper Triassic age were analyzed. Samples of carbonate rocks were pulverized and ground to fraction of 45 μm and for determination of δ13CCaCO3 analyzed with mass spectrometer for analyses of stable isotopes of light elements-IRMS. The same method was used for determination of isotopic composition of dissolved inorganic carbon (δ13CDIC in groundwater for 54 of 59 locations. Values of δ13CCaCO3 are in the range from -2.0 ‰ to +4.1 ‰, with an average δ13CCaCO3 value of +2.2 ‰. These values are typical for marine carbonates with δ13CCaCO3 around 0 ‰, although δ13CCaCO3 values differ between groups depending on the origin and age. Early diagenetic dolomites have relatively higher values of δ13CCaCO3 compared to other analyzed samples. The lowest values of δ13CCaCO3 were observed in Cordevolian and Bača dolomite, probably due to late diagenesis, during which meteoric water with lower isotopic carbon composition circulated in the process of sedimentation. Values of δ13CDIC range from -14.6 ‰ to -8.2 ‰. Higher δ13CDIC values (-8.2 ‰ indicate a low proportion of soil CO2 in the aquifer and rapid infiltration, while lower values (-14.6 ‰ indicate higher proportion of soil CO2 in the aquifer and slower infiltration. Calculated contributions of carbon from organic matter / dissolution of carbonates in the karstic and fissured aquifers s how a similar proportion (50 % : 50 %.

Results of the study of a new Groznensky Field with fissured reservoir rocks

Energy Technology Data Exchange (ETDEWEB)

Lebedinets, N P; Merkulov, A V; Pristanskii, G T; Postash, M F

1970-06-01

Geological information on the Eldarovsky field, situated in the central part of Tersky anticlinal zone and discovered in 1964, is given. Commercial quantities of oil were discovered in the foraminifera (thickness 40 to 70 m) and Upper Cretaceous (305 to 330 m thickness) deposits, consisting of fissured limestones and marls. Both the foraminifera and Upper Cretaceous deposits are divided into various zones which are hydrodynamically connected with each other and constitute a single pool. No hydrodynamical connection was observed between the Eldarovsky pools and surrounding oil fields. The secondary porosity of the Upper Cretaceous and forammifera deposits is 0.49% and 0.2%, respectively, and is responsible for most of the oil reserves. The analysis of the pressure buildup curves shows that the field has an elastic water drive.

The temporal requirement for vitamin A in the developing eye: mechanism of action in optic fissure closure and new roles for the vitamin in regulating cell proliferation and adhesion in the embryonic retina.

Science.gov (United States)

See, Angela Wai-Man; Clagett-Dame, Margaret

2009-01-01

Mammalian eye development requires vitamin A (retinol, ROL). The role of vitamin A at specific times during eye development was studied in rat fetuses made vitamin A deficient (VAD) after embryonic day (E) 10.5 (late VAD). The optic fissure does not close in late VAD embryos, and severe folding and collapse of the retina is observed at E18.5. Pitx2, a gene required for normal optic fissure closure, is dramatically downregulated in the periocular mesenchyme in late VAD embryos, and dissolution of the basal lamina does not occur at the optic fissure margin. The addition of ROL to late VAD embryos by E12.5 restores Pitx2 expression, supports dissolution of the basal lamina, and prevents coloboma, whereas supplementation at E13.5 does not. Surprisingly, ROL given as late as E13.5 completely prevents folding of the retina despite the presence of an open fetal fissure, showing that coloboma and retinal folding represent distinct VAD-dependent defects. Retinal folding due to VAD is preceded by an overall reduction in the percentage of cyclin D1 positive cells in the developing retina, (initially resulting in retinal thinning), as well as a dramatic reduction in the cell adhesion-related molecules, N-cadherin and beta-catenin. Reduction of retinal cell number combined with a loss of the normal cell-cell adhesion proteins may contribute to the collapse and folding of the retina that occurs in late VAD fetuses.

Geologic and geotechnical investigation of the Windsor Park subdivision North Las Vegas, Nevada

International Nuclear Information System (INIS)

Linnert, L.M.; Werle, J.L.; Stilley, A.N.; Olsen, B.L.

1994-01-01

The Windsor Park subdivision in North Las Vegas, Nevada has received widespread attention for damage to the homes and infrastructure from fissures, land subsidence and adverse soil conditions. Between March and July, 1992, Converse Consultants Southwest, Inc. conducted a geologic and geotechnical investigation for the Windsor Park Revitalization Project. The purpose of the work was to investigate the probable factors contributing to the reported damage and distress in the area, evaluate the potential for future damage, and assess the feasibility of possible mitigation and repair. The site is constructed on the juncture of at least two subsidence-related fault scarps, and earth fissures have been extensively mapped in the Windsor Park and surrounding area. A total of twenty-one trenches and fifteen borings were located within the subdivision and around the perimeter to observe subsurface geologic features and to collect samples for laboratory testing. The primary causes of damage within the development were found to be (1) earth fissuring and (2) expansive clays. The risk of future damage to structures at the Windsor Park site was also evaluated. A high potential for fissuring was found at the site, and future structural distress in the area will likely be similar to past damage. Although engineering upgrades will reduce the risk posed by underlying expansive clays, they cannot totally eliminate the risk from fissuring. 10 refs., 8 figs., 1 tab

Influence of Fissure Number on the Mechanical Properties of Layer-Crack Rock Models under Uniaxial Compression

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Yun-liang Tan

2018-01-01

Full Text Available Many case studies have revealed that rock bursts generally occur in the high stress concentration area where layer-crack structures often exist, especially for brittle coal or rock masses. Understanding the mechanical properties of layer-crack rock models is beneficial for rational design and stability analysis of rock engineering project and rock burst prevention. This study experimentally investigated the influence of fissure number on the mechanical properties of layer-crack rock models through uniaxial compression tests. The digital speckle correlation method (DSCM and acoustic emission (AE techniques were applied to record and analyze the information of deformation and failure processes. Test results show the following: the bearing capacity of layer-crack specimen decreases compared with intact specimen, but their failure modes are similar, which are the splitting failure accompanied with local shear failure; the nonuniform deformation phenomenon begins to appear at the elastic deformation stage for layer-crack specimens; the AE behavior of intact specimens consists of three stages, that is, active stage, quiet stage, and major active stage, but for layer-crack specimens, it is characteristic by three peaks without quiet stage. In addition, as the fissure number of layer-crack specimens increases, the bearing capacity of specimens decreases, the appearing time of nonuniform deformation phenomenon in the specimen surface decreases, the AE events are denser and denser in each peak stage, and the risk of dynamic instability of layer-crack structure increases. At last, the failure mechanism of layer-crack structure and the related mitigation advices were discussed based on the test results. In general, the novelty is that this paper focuses on the failure mechanism of layer-crack structure directly.

Results from impression packer technique for location of fissures in boreholes in white chalk, Mors, Denmark

International Nuclear Information System (INIS)

Andersen, L.J.; Byrne, L.; Frykman, P.

1981-01-01

In connection with site investigations to evaluate the possibility of geological disposal of radioactive waste in a salt dome a Hydrogeological Programme was carried out. A number of bore holes were drilled to depths of 550 m. Geological and hydrogeological investigations were performed. The hydrogeological tests were carried out as packer tests, bottomhole tests using one packer, or straddle-packer test using two packers. In connection with these tests a rubber sleeve was installed over the packer and sidewall impressions of the hole were taken. Irregularities such as faults and fissures and possibly solution features were localized. The paper describes the method, procedure, equipment and the results achieved

Automatic classification of pulmonary peri-fissural nodules in computed tomography using an ensemble of 2D views and a convolutional neural network out-of-the-box

NARCIS (Netherlands)

Ciompi, Francesco; de Hoop, Bartjan; van Riel, Sarah J.; Chung, Kaman; Scholten, Ernst Th.; Oudkerk, Matthijs; de Jong, Pim A.; Prokop, Mathias; van Ginneken, Bram

2015-01-01

In this paper, we tackle the problem of automatic classification of pulmonary peri-fissural nodules (PFNs). The classification problem is formulated as a machine learning approach, where detected nodule candidates are classified as PFNs or non-PFNs. Supervised learning is used, where a classifier is

Micromorphological features of the fine earth and skeletal fractions of soils of West Antarctica in the areas of Russian Antarctic stations

Science.gov (United States)

Abakumov, E. V.; Gagarina, E. I.; Sapega, V. F.; Vlasov, D. Yu.

2013-12-01

Micromorphological features of the fine earth and skeletal fractions of soils of West Antarctica forming under different conditions of pedogenesis have been studied in the areas of Russian Antarctic stations. The processes of mineral weathering and alteration of rock fragments are more pronounced in the Subantarctic soils with better developed humification and immobilization of iron compounds under conditions of surface overmoistening. The biogenic accumulative processes in the soils of King George Island result in the appearance of initial forms of humic plasma that have not been detected in the Antarctic soils in the areas of the Russkaya and Leningradskaya stations. Humus films on mineral grains are present in the soils of King George Island, and organic plasmic material is present in the ornithogenic soils under penguin guano on Lindsey Island. High-latitude Antarctic soils may contain surface concentrations of organic matter; rock fragments are covered by iron oxides and soluble salts. The formation of amorphous organic plasma takes place in the ornithogenic soils of Lindsey Island. The microprobe analysis indicates the presence of local concentrations of organic matter and pedogenic compounds not only on the surface of rock fragments but also in the fissures inside them. This analysis has also proved the translocation of guano-derived organic substances inside rock fragments through a system of fissures in the soils of Lindsey Island and the development of a network of pores inside rock fragments in the soils of King George Island.

Knowledge, value, opinion and practice about usage of pit and fissure sealant among dental professionals in Chennai, Tamil Nadu, India.

Science.gov (United States)

Nagappan, N; Dhamodhar, M Dinesh; Nithin, M G; Kumar, E Senthil

2015-12-01

A study was aimed to assess the knowledge, value, opinion, and practice regarding the use of dental sealants among private dental practitioners in Chennai, Tamil Nadu, India. A self-administrated questionnaire were distributed to 192 private dental practitioners in Chennai, Tamil Nadu, India by using simple random sampling. A convenience sampling technique was employed. The questionnaire consisted of 28 items, which included information about knowledge, value, opinion, and practice regarding dental sealants. The questionnaire was obtained from the study by San Martin et al. 2013 and Kailash Asawa et al. 2014. Frequency distribution was tabulated. For frequency distribution strongly, strongly agree, and agree were combined as "agree" and strongly disagree and disagree were combined as "disagree." There were no changes in "neutral." Among the 196 study subjects 56.2% were males and 43.8% were females with their clinical experience of 52.1% for 15 years. The mean scores for knowledge, value, opinion, and practice were 41.8 ± 3.7, 18.7 ± 2.8, 18.1 ± 1.4, and 12.9 ± 2.3, respectively. The results suggest that dental practitioners had satisfactory knowledge about pit and fissure sealant and had neutral attitudes about sealants being effective. Dental practitioners adequately used the pit and fissure sealants but they did not follow the standardized procedures and specific guidelines.

Earth fissures in Qinglong Graben in Yuncheng Basin, China

Indian Academy of Sciences (India)

Jianwei Qiao

2018-02-14

Feb 14, 2018 ... Key Laboratory of Western China Mineral Resources and Geological Engineering, Xi'an 710 054, Shaanxi, China. *Corresponding .... first to appear in edge and then extended to the center. ..... Miao D Y, Li Y L, Lv S H, Tian J M, Wang Y R and Si ... Wang J M, Wang C M and Liu K 2001 Progress in ground.

D/N and /sup 18/O//sup 16/O in magmatic waters and gases of the Great Tolbachik fissure eruption, Kamchatka

Energy Technology Data Exchange (ETDEWEB)

Menyailov, I A; Vetshtein, V E; Nikitina, L P; Artemchuk, V G [AN SSSR, Petropavlovsk-Kamchatskii. Inst. Vulkanologii; AN Ukrainskoj SSR, Kiev. Inst. Geokhimii i Fiziki Mineralov)

1981-01-01

Isotope content of magmatic gases and their condensates (magmatic waters) is studied on the basis of the Great Tolbachik fissure eruption, Kamchatka. The phenomenon of regular increase of deuterium content in magmatic water and protium content in gases is found out. It is supposed that this fact is conditioned by isotope fractionation during phase transitions in liquid-steam-gas system in the process of the formation of magmatic hearth and gas release from magma during eruption.

Filaggrin loss-of-function mutation R501X and 2282del4 carrier status is associated with fissured skin on the hands: results from a cross-sectional population study

DEFF Research Database (Denmark)

Thyssen, J P; Ross-Hansen, K; Johansen, J D

2012-01-01

Background: Filaggrin metabolites act as osmolytes and are important for skin hydration. Carriers of filaggrin loss-of-function mutations have a higher prevalence of atopic dermatitis and dry skin. There is also evidence to suggest that filaggrin mutations increase the risk of hand eczema in atopic...... whether filaggrin loss-of-function mutations are associated with skin fissures on the hands and/or fingers in the general population. Design: Participants of a population based study were questioned about skin symptom and genotyped for filaggrin mutation, patch tested for nickel allergy and skin prick...... tested. Results: In an adjusted logistic regression analysis, filaggrin mutation status was significantly associated with fissured skin on the hands and/or fingers in adults (OR=1.93; CI95%=1.05-3.55) and a near significant negative interaction with atopic dermatitis (p=0.055), suggesting the effect...

Retalhos de avanço no tratamento da fissura anal crônica: experiência inicial Advancement flap in the treatment of chronic anal fissure: inicial experience

Directory of Open Access Journals (Sweden)

Maria Auxiliadora Prolungatti Cesar

2009-12-01

Full Text Available A fissura anal é uma laceração do canal anal relacionada ao trauma, hipertonia esfincteriana e isquemia. A maioria cicatriza espontaneamente ou com tratamento conservador, e poucas requerem tratamento cirúrgico. O objetivo deste trabalho é verificar os resultados clínicos e alterações manométricas de pacientes submetidos ao tratamento cirúrgico da fissura anal com avançamento de retalhos em v-y. Métodos: Estudo prospectivo, realizado nos anos de 2007, 2008 e 2009, que abrangeu nove pacientes portadores de fissura anal crônica submetidos ao avançamento de retalho anal. Foram avaliadas as pressões do canal anal ao repouso, contração e esforço evacuatório; no pré e pós-operatório. Resultados: Na amostra, todos os pacientes apresentaram hipertonia esfincteriana prévia. seis (66,6% obtiveram resolução total dos sintomas e das lesões. Um (11,11% sofreu deiscência parcial do retalho, sem sintomas clínicos; e outros dois (22,22%, infecção com perda dos mesmos e persistência da fissura. A análise manométrica das pressões de repouso, contração e evacuação nos grupos não mostrou alteração estatisticamente significativa (p>0,05, o que comprova que a cirurgia não incluiu manipulação dos esfíncteres. Conclusão: Os retalhos anais mostraram-se efetivos no tratamento da fissura anal, com cicatrização da lesão, sem que ocorram alterações nas pressões anais desses pacientes.The anal fissure is a laceration of the anal canal related to trauma, hypertonic sphincter and ischemia. The majority heals spontaneously or with conservative treatment and only a few requires surgical treatment. The objective of this study is to verify the clinical results and manometric alterations of patients submitted to the surgical treatment of the anal fissure with advance of v-y skin flaps. Methods: Prospective study, accomplished in 2007,2008 and 2009, in witch nine patients with chronic anal fissure were submitted to v-y advance. The

Sylvian Fissure and Parietal Anatomy in Children with Autism Spectrum Disorder

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Tracey A. Knaus

2012-01-01

Full Text Available Autism spectrum disorder (ASD is characterized by deficits in social functioning and language and communication, with restricted interests or stereotyped behaviors. Anatomical differences have been found in the parietal cortex in children with ASD, but parietal subregions and associations between Sylvian fissure (SF and parietal anatomy have not been explored. In this study, SF length and anterior and posterior parietal volumes were measured on MRI in 30 right-handed boys with ASD and 30 right-handed typically developing boys (7–14 years, matched on age and non-verbal IQ. There was leftward SF and anterior parietal asymmetry, and rightward posterior parietal asymmetry, across groups. There were associations between SF and parietal asymmetries, with slight group differences. Typical SF asymmetry was associated with typical anterior and posterior parietal asymmetry, in both groups. In the atypical SF asymmetry group, controls had atypical parietal asymmetry, whereas in ASD there were more equal numbers of individuals with typical as atypical anterior parietal asymmetry. We did not find significant anatomical-behavioral associations. Our findings of more individuals in the ASD group having a dissociation between cortical asymmetries warrants further investigation of these subgroups and emphasizes the importance of investigating anatomical relationships in addition to group differences in individual regions.

Hypoplasia of the basi-occipital bone and persistance of the spheno-occipital synchondrosis in a patient with transitory supplementary fissure of the basi-occipital

International Nuclear Information System (INIS)

Wackenheim, A.

1985-01-01

The author had the opportunity to observe the progressive development of a special form of basilar impression characterized by transitory supplementary fissure of the basi-occipital bone, persistance of the spheno-occipital synchondrosis and hypoplasia of the basi-occipital. He proposes to dissociate the general concept of basilar impression and to consider anatomo-clinical entities such as the example described in this paper. (orig.)

Comparison of six different methods of cleaning and preparing occlusal fissure surface before placement of pit and fissure sealant: An in vitro study

Directory of Open Access Journals (Sweden)

A Agrawal

2012-01-01

Full Text Available Aim & Objectives : The purpose of this in vitro study was to evaluate and compare the microleakage of pit and fissure sealants after using six different preparation techniques: (a brush, (b pumice slurry application, (c bur, (d air polishing, (e air abrasion, and (f longer etching time. Material & Method : The study was conducted on 60 caries-free first premolars extracted for orthodontic purpose. These teeth were randomly assigned to six groups of 10 teeth each. Teeth were prepared using one of six occlusal surface treatments prior to placement of Clinpro" 3M ESPE light-cured sealant. The teeth were thermocycled for 500 cycles and stored in 0.9% normal saline. Teeth were sealed apically and coated with nail varnish 1 mm from the margin and stained in 1% methylene blue for 24 hours. Each tooth was divided buccolingually parallel to the long axis of the tooth, yielding two sections per tooth for analysis. The surfaces were scored from 0 to 2 for the extent of microleakage. Statistical Analysis : Results obtained for microleakage were analyzed by using t-tests at sectional level and chi-square test and analysis of variance (ANOVA at the group level. Results : The results of round bur group were significantly superior when compared to all other groups. The application of air polishing and air abrasion showed better results than pumice slurry, bristle brush, and longer etching time. Round bur group was the most successful cleaning and preparing technique. Air polishing and air abrasion produced significantly less microleakage than traditional pumice slurry, bristle brush, and longer etching time.

Acid neutralizing, mechanical and physical properties of pit and fissure sealants containing melt-derived 45S5 bioactive glass.

Science.gov (United States)

Yang, Song-Yi; Piao, Yin-Zhu; Kim, Sung-Min; Lee, Yong-Keun; Kim, Kyoung-Nam; Kim, Kwang-Mahn

2013-12-01

The aim of this study was to examine the effects of 45S5 bioactive glass (BAG) on the acid neutralizing, mechanical and physical properties of pit and fissure sealants. 45S5BAG (glass (180 ± 30 nm) and added into a resin matrix [Bis-GMA/TEGDMA 50/50 (wt%) containing 1% of DMAEMA/CQ 2:1 (wt%)] with varying filler proportions; 0% 45S5BAG+50% glass (BAG0); 12.5% 45S5BAG+37.5% glass (BAG12.5); 25% 45S5BAG+25% glass (BAG25); 37.5% 45S5BAG+12.5% glass (BAG37.5); and 50% 45S5BAG+0% glass (BAG50). To evaluate the acid neutralizing properties, specimens were immersed in lactic acid solution (pH 4.0). Then, the change in pH and the time required to raise the pH from 4.0 to 5.5 were measured. In addition, flexural strength, water sorption and solubility were analyzed. The acid neutralizing properties of each group exhibited increasing pH values as more 45S5BAG was added, and the time required to raise the pH from 4.0 to 5.5 became shorter as the proportion of 45S5BAG increased (P0.05), except for BAG50. The novel pit and fissure sealants neutralized the acid solution (pH 4.0) and exhibited appropriate mechanical and physical properties. Therefore, these compounds are suitable candidates for caries-inhibiting dental materials. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

The effect of a chlorhexidine-fluoride varnish on mutans streptococci counts and laser fluorescence readings in occlusal fissures of permanent teeth

DEFF Research Database (Denmark)

Lipták, Lídia; Bársony, Nóra; Twetman, Svante

2016-01-01

Objective: To evaluate the effect of a new chlorhexidinefluor ide varnish on mutans streptococci (MS) counts and laser fluorescence (LF) readings in fissures of permanent molars. Method and Materials: The study group consisted of 57 healthy schoolchildren (7 to 14 yrs) that volunteered after...... informed consent. A double-blind split-mouth design was employed and 87 pairs of non-cavitated permanent molars were randomly assigned to treatments with either chlorhexidine- fluoride varnish (CHX-F) or chlorhexidine-thymol varnish (CHX-T, Cervitec Plus) as active control. The varnishes were topically...

Some unique surface patterns on ignimbrites on Earth: A "bird's eye" view as a guide for planetary mappers

Science.gov (United States)

de Silva, Shanaka L.; Bailey, John E.

2017-08-01

Observations of terrestrial analogs are critical to aiding planetary mappers in interpreting surface lithologies on other planets. For instance, the presence of ignimbrites on Mars has been debated for over three decades and is supported by analogy with deposits on Earth. Critical evidence includes the geomorphic and surface expression of the deposits, and those in the Central Andes of South America are amongst the most-cited analogs. Herein we describe some prominent surface textures and patterns seen in ignimbrites on the scale of high-resolution remotely sensed data (10-1 m per pixel). These include pervasive joints and fractures that contribute to yardang form and development as well as prominent mounds, fissures, and fracture networks ("spiders", "bugs", "boxworks") on ignimbrite surfaces. While all these features are related to intrinsic cooling and degassing processes, the involvement of external water buried by hot pyroclastic flows enhances fumarolic activity, advective cooling, and joint development. Observations of these geomorphic expressions using remote sensing are only possible with the highest resolution data and limited surface erosion. For Mars, where similarly high resolution datasets are available (for example, the High Resolution Imaging Sensor Experiment or HiRISE) extensive dust cover may limit the recognition of similar features there. However significant relief on some of these features on Earth indicate they might still be detectable on Mars.

Short-time variations of the ground water level

International Nuclear Information System (INIS)

Nilsson, Lars Y.

1977-09-01

Investigations have demonstrated that the ground water level of aquifers in the Swedish bedrock shows shorttime variations without changing their water content. The ground water level is among other things affected by regular tidal movements occuring in the ''solid'' crust of the earth variations in the atmospheric pressure strong earthquakes occuring in different parts of the world These effects proves that the system of fissures in the bedrock are not stable and that the ground water flow is influenced by both water- and airfilled fissures

Dispersion and concentration of elements in the Earth's crust an overview

International Nuclear Information System (INIS)

Iiyama, J.T.

1991-01-01

During the Earth's history of 4,500 x 10 6 years, the distribution of elements in its crust is strongly modified from the initial pattern. The paper overlooks at first how and to what extent this modification could be take place. It is emphasized that water in deep as well as in shallow parts of the crust plays an essential role in the transportation of elements. Whether a particular element thus transported by water are concentrated in particular places or diluted and dispersed in the crust or brought to the surface and join into the surface water depends on the geological and geochemical condition of the passages of these waters acting as transporter of the elements. If there was no preferential passages for water, these elements and water will diffuse into the surroundings and no particular concentration of elements will be resulted. On the contrary, the presence of preferential conduit (such as fissure or faults) will offer the places adequate for this concentration provided that a favorable physical and chemical conditions are present. The review thus intends to point out the importance of the tectono-geochemical conditions to be taken into consideration for the planning of the nuclear wastes disposal and of the environmental protection. (author)

Earth mortars and earth-lime renders

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Maria Fernandes

2008-01-01

Full Text Available Earth surface coatings play a decorative architectural role, apart from their function as wall protection. In Portuguese vernacular architecture, earth mortars were usually applied on stone masonry, while earth renders and plasters were used on indoors surface coatings. Limestone exists only in certain areas of the country and consequently lime was not easily available everywhere, especially on granite and schist regions where stone masonry was a current building technique. In the central west coast of Portugal, the lime slaking procedure entailed slaking the quicklime mixed with earth (sandy soil, in a pit; the resulting mixture would then be combined in a mortar or plaster. This was also the procedure for manufactured adobes stabilized with lime. Adobe buildings with earth-lime renderings and plasters were also traditional in the same region, using lime putty and lime wash for final coat and decoration. Classic decoration on earth architecture from the 18th-19th century was in many countries a consequence of the François Cointeraux (1740-1830 manuals - Les Cahiers d'Architecture Rurale" (1793 - a French guide for earth architecture and building construction. This manual arrived to Portugal in the beginning of XIX century, but was never translated to Portuguese. References about decoration for earth houses were explained on this manual, as well as procedures about earth-lime renders and ornamentation of earth walls; in fact, these procedures are exactly the same as the ones used in adobe buildings in this Portuguese region. The specific purpose of the present paper is to show some cases of earth mortars, renders and plasters on stone buildings in Portugal and to explain the methods of producing earth-lime renders, and also to show some examples of rendering and coating with earth-lime in Portuguese adobe vernacular architecture.

Three-armed rifts or masked radial pattern of eruptive fissures? The intriguing case of El Hierro volcano (Canary Islands)

Science.gov (United States)

Becerril, L.; Galindo, I.; Martí, J.; Gudmundsson, A.

2015-04-01

Using new surface structural data as well as subsurface structural data obtained from seventeen water galleries, we provide a comprehensive model of the volcano-tectonic evolution of El Hierro (Canary Islands). We have identified, measured and analysed more than 1700 volcano-structural elements including vents, eruptive fissures, dykes and faults. The new data provide important information on the main structural patterns of the island and on its stress and strain fields, all of which are crucial for reliable hazard assessments. We conducted temporal and spatial analyses of the main structural elements, focusing on their relative age and association with the three main cycles in the construction of the island: the Tiñor Edifice, the El Golfo-Las Playas Edifice, and the Rift Volcanism. A radial strike distribution, which can be related to constructive episodes, is observed in the on-land structures. A similar strike distribution is seen in the submarine eruptive fissures, which are radial with respect to the centre of the island. However, the volcano-structural elements identified onshore and reflecting the entire volcano-tectonic evolution of the island also show a predominant NE-SW strike, which coincides with the main regional trend of the Canary archipelago as a whole. Two other dominant directions of structural elements, N-S and WNW-ESE, are evident from the establishment of the El Golfo-Las Playas edifice, during the second constructive cycle. We suggest that the radial-striking structures reflect comparatively uniform stress fields during the constructive episodes, mainly conditioned by the combination of overburden pressure, gravitational spreading, and magma-induced stresses in each of the volcanic edifices. By contrast, in the shallower parts of the edifice the NE-SW, N-S and WNW-ESE-striking structures reflect local stress fields related to the formation of mega-landslides and masking the general and regional radial patterns.

Hawaiian fissure fountains: Quantifying vent and shallow conduit geometry, episode 1 of the 1969-1974 Mauna Ulu eruption: Chapter 17

Science.gov (United States)

Parcheta, Carolyn; Fagents, Sarah; Swanson, Donald A.; Houghton, Bruce F.; Ericksen, Todd; Carey, Rebecca; Cayol, Valérie; Poland, Michael P.; Weis, Dominique

2015-01-01

Geometries of shallow magmatic pathways feeding volcanic eruptions are poorly constrained, yet many key interpretations about eruption dynamics depend on knowledge of these geometries. Direct quantification is difficult because vents typically become blocked with lava at the end of eruptions. Indirect geophysical techniques have shed light on some volcanic conduit geometries, but the scales are too coarse to resolve narrow fissures (widths typically 1 m). Kīlauea's Mauna Ulu eruption, which started with 30 m. Direct measurements at the ground surface were augmented by tripod-mounted lidar measurements to quantify the shallow conduit geometry for three vents at a resolution eruptive behavior, especially if incorporated into computer models.

Geographic Tongue and Fissured Tongue in 348 Patients with Psoriasis: Correlation with Disease Severity

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Bruna L. S. Picciani

2015-01-01

Full Text Available Geographic tongue (GT and fissured tongue (FT are the more frequent oral lesions in patients with psoriasis. The aims of this study were to compare the prevalence of GT/FT between psoriasis group (PG and healthy controls (HC and investigate the correlation between GT/FT and psoriasis severity using the PASI and age of psoriasis onset. Three hundred and forty-eight PG and 348 HC were selected. According to the age of psoriasis onset, the individuals were classified as having early psoriasis and late psoriasis. The severity of vulgaris psoriasis was determined according to PASI. A follow-up was conducted in patients with psoriasis vulgaris (PV with GT to evaluate the progression of oral and cutaneous lesions. The FT and GT were more frequent in PG than in HC. The incidence of GT was higher in patients with early psoriasis and that of FT in late-psoriasis. There is association between psoriasis intensity and GT; and a higher monthly decrease of PASI score in patients without GT. The presence of GT and FT is higher in PG than in the HC. GT is associated with disease severity and may be a marker of the psoriasis severity.

Effect of artificial aging on the bond durability of fissure sealants.

Science.gov (United States)

Yun, Xiaofei; Li, Wei; Ling, Chen; Fok, Alex

2013-06-01

To evaluate the effect of artificial aging on the bond durability of fissure sealants in vitro. Twenty bovine incisors received 4 different sealant treatments and were divided into four groups: 1. Ultraseal XT plus (UX); 2. Enamel Loc (EL); 3. 35% phosphoric acid plus Enamel Loc (PEL); 4. Adper Prompt L-Pop plus Clinpro (PPC). Beam-shaped specimens were prepared and randomly divided into three subgroups. One subgroup underwent the microtensile bond strength (µTBS) test after 24-h storage in 37°C water. The other two subgroups were also subjected to the microtensile bond strength test after 5000 and 10,000 thermal cycles, respectively. Another twelve intact human third molars were sealed using 1 of 3 methods and were divided into 3 groups of 4 each: 1. Ultraseal XT plus; 2. Adper Prompt L-Pop plus Clinpro; and 3. Enamel Loc. Two specimens from each group were immersed in a 50% silver nitrate solution for 24 h, followed by exposure to fluorescent light for 8 h, before being scanned in a micro-CT (microcomputer tomography) machine. The other two were handled in the same way after undergoing 10,000 thermal cycles. The CT images obtained were evaluated. All samples from the EL group were broken during preparation, so no µTBS results were available. After 5000 thermal cycles, the bond strengths of the three other groups (UX, PEL, PPC) decreased significantly (p artificial aging. Micro-CT, a nondestructive analytical tool, may be used to evaluate the sealant/enamel interface effectively.

Effect of occlusal calculus utilized as a potential "biological sealant" in special needs patients with gastric feeding tubes: a qualitative in vitro contrast to pit and fissure sealant restorations.

Science.gov (United States)

Owens, Barry M; Sharp, Harry K; Fourmy, Emily E; Phebus, Jeffrey G

2016-01-01

The aim of this case report and in vitro investigation was to evaluate the marginal microleakage of intact occlusal calculus of primary molars extracted from a special needs patient who received nutrition via a gastric feeding tube. An adolescent with a history of developmental disturbance presented for routine dental care in a hospital facility. Prophylaxis was performed, and 2 mandibular permanent molars were restored. Five primary molars were extracted due to mobility and delayed retention. Heavy deposits of intact calculus were present on the occlusal surfaces of the primary teeth. The extracted teeth were immersed in methylene blue dye solution, invested in acrylic resin, sectioned into blocks, and photographed at 20× and 40× magnification. Previously photographed calculus-free molars with pit and fissure sealants were reviewed and served as contrasting "restorations." The occlusal calculus on the primary teeth extracted from the patient absorbed the dye, while the comparison teeth containing pit and fissure sealants exhibited varying degrees of marginal dye penetration (microleakage). No marginal microleakage was noted in the calculus specimens, indicating that this substrate may serve as a "natural" occlusal surface sealant and that its removal from occlusal surfaces during routine oral prophylaxis may be unnecessary.

Estudo comparativo das medidas manual e digital da fenda palpebral A comparative study of the manual and digital measurements of the palpebral fissure

Directory of Open Access Journals (Sweden)

Tânia Pereira Nunes

2005-12-01

Full Text Available OBJETIVO: Comparar a medida manual do comprimento vertical da fenda palpebral e sua medida obtida por meio de processamento computadorizado de imagens de indivíduos sem alterações palpebrais. MÉTODOS: Foram analisadas 102 fendas palpebrais de 51 indivíduos normais. A faixa etária variou entre 17 e 84 anos, sendo 25 (49% do sexo masculino e 26 (51% do sexo feminino. RESULTADOS: Não houve diferença estatisticamente significativa entre as medidas manuais da fenda palpebral e as obtidas por meio de processamento computadorizado de imagens. Também não se observou diferença entre ambos os sexos e a faixa etária. CONCLUSÕES: Os resultados obtidos com estes dois métodos podem ser comparados entre si devida à equivalência estatística das medidas.PURPOSE: To compare the measurement of the palpebral fissure done either manually and by computer analysis of image of individuals without lid alterations. METHODS: One hundred two palpebral fissures from 51 normal subjects have been analyzed. The patients' age ranged from 17 to 84 years, with 25 (49% males and 26 (51% females. RESULTS: There was no statistically significant difference between the measurements done either manually or by computer analysis of images, neither, when we grouped the patients by sex or age. Also we did not observe difference between males and females, and regarding age. CONCLUSIONS: The results obtained by both methods are comparable and reliable due to the statistical equivalence of the obtained measurements.

An Earth-sized planet with an Earth-like density.

Science.gov (United States)

Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

2013-11-21

Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

Towards earth AntineutRino TomograpHy (EARTH)

NARCIS (Netherlands)

De Meijer, R. J.; Smit, F. D.; Brooks, F. D.; Fearick, R. W.; Wortche, H. J.; Mantovani, F.

2006-01-01

The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection.

Genetic Susceptibility to Dental Caries on Pit and Fissure and Smooth Surfaces

Science.gov (United States)

Shaffer, J.R.; Wang, X.; DeSensi, R.S.; Wendell, S.; Weyant, R.J.; Cuenco, K.T.; Crout, R.; McNeil, D.W.; Marazita, M.L.

2012-01-01

Carious lesions are distributed nonuniformly across tooth surfaces of the complete dentition, suggesting that the effects of risk factors may be surface-specific. Whether genes differentially affect caries risk across tooth surfaces is unknown. We investigated the role of genetics on two classes of tooth surfaces, pit and fissure surfaces (PFS) and smooth surfaces (SMS), in more than 2,600 subjects from 740 families. Participants were examined for surface-level evidence of dental caries, and caries scores for permanent and/or primary teeth were generated separately for PFS and SMS. Heritability estimates (h2, i.e. the proportion of trait variation due to genes) of PFS and SMS caries scores were obtained using likelihood methods. The genetic correlations between PFS and SMS caries scores were calculated to assess the degree to which traits covary due to common genetic effects. Overall, the heritability of caries scores was similar for PFS (h2 = 19–53%; p caries scores for both PFS and SMS in the primary dentition was greater than in the permanent dentition and total dentition. With one exception, the genetic correlation between PFS and SMS caries scores was not significantly different from 100%, indicating that (mostly) common genes are involved in the risk of caries for both surface types. Genetic correlation for the primary dentition dfs (decay + filled surfaces) was significantly less than 100% (p caries risk in PFS versus SMS in the primary dentition. PMID:22286298

Rare earth metals, rare earth hydrides, and rare earth oxides as thin films

International Nuclear Information System (INIS)

Gasgnier, M.

1980-01-01

The review deals with pure rare earth materials such as rare earth metals, rare earth hydrides, and rare earth oxides as thin films. Several preparation techniques, control methods, and nature of possible contaminations of thin films are described. These films can now be produced in an extremely well-known state concerning chemical composition, structure and texture. Structural, electric, magnetic, and optical properties of thin films are studied and discussed in comparison with the bulk state. The greatest contamination of metallic rare earth thin films is caused by reaction with hydrogen or with water vapour. The compound with an f.c.c. structure is the dihydride LnH 2 (Ln = lanthanides). The oxygen contamination takes place after annealing at higher temperatures. Then there appears a compound with a b.c.c. structure which is the C-type sesquioxide C-Ln 2 O 3 . At room atmosphere dihydride light rare earth thin films are converted to hydroxide Ln(OH) 3 . For heavy rare earth thin films the oxinitride LnNsub(x)Osub(y) is observed. The LnO-type compound was never seen. The present review tries to set the stage anew for the investigations to be undertaken in the future especially through the new generations of electron microscopes

An Experimental Study of the Fracture Coalescence Behaviour of Brittle Sandstone Specimens Containing Three Fissures

Science.gov (United States)

Yang, S. Q.; Yang, D. S.; Jing, H. W.; Li, Y. H.; Wang, S. Y.

2012-07-01

To analyse the fracture coalescence behaviour of rock, rectangular prismatic sandstone specimens (80 × 160 × 30 mm in size) containing three fissures were tested under uniaxial compression. The strength and deformation behaviours of the specimens are first analysed by investigating the effects of the ligament angle β2 on the peak strength, peak strain and crack initiation stress of the specimens. To confirm the sequence of crack coalescence, a photographic monitoring technique is used throughout the entire period of deformation. Based on the results, the relationship between the real-time crack coalescence process and the axial stress-strain curve of brittle sandstone specimens is also developed, and this relationship can be used to evaluate the macroscopic deformation characteristics of pre-cracked rock. The equivalent strain evolution fields of the specimen, with α = β1 = 45° and β2 = 90°, are obtained using the digital image correlation technique and show good agreement with the experimental results of pre-cracked brittle sandstone. These experimental results are expected to improve the understanding of fracture mechanisms and be used in rock engineering with intermittent structures, such as deep underground excavated tunnels.

Analyse des propriétés hydrodynamiques des aquifères fissurés de la région de San-Pedro (Sud-Ouest de la Côte d’Ivoire

Directory of Open Access Journals (Sweden)

De-Lasme, O. Z.

2012-12-01

Full Text Available San-Pedro area is localized in south-western Côte d’Ivoire and covers a surface of 6912 km². Wa t e r resources exploited in this area are constituted of surface waters and groundwater of weathered and fissured aquifers. The aims of this study are to analyze hydrodynamic properties of fissured aquifers of San-Pedro on statistical and geostatistical viewpoints for a better knowledge and management of groundwater resources. Data base includes 110 drillings tapping fissured aquifers. Transmissivity was calculated by interpreting of pumping tests with classical methods. Specific capacity was calculated at the end of the third step for all drillings after correction of drawdowns. Transmissivity and specific capacity values oscillate between 1,27.10^-6 and 8,59.10-⁴ m².s^-1 and between 1,09.10^-2 m².h^-1 et 13,2 m².h^-1, respectively. These two parameters span three orders of magnitude showing the strong heterogeneity of the medium. An empirical relationship was established between transmissivity and specific capacity of San-Pedro area. This relationship can be used to determine transmissivity in the sectors where this data is lacking. Variogram of transmissivity is characterized by a double structuring. Transmissivity assessment by kriging is satisfactory, observed and estimated values are comparable. The findings obtained in this study lead to a better understanding of hydrogeological properties of south-western Côte d’Ivoire.

[fr] La région de San-Pedro est localisée dans le sud-ouest de la Côte d’Ivoire et couvre une superficie de 6912 km². Les ressources en eau exploitées dans cette région sont constituées des eaux de surface et des eaux souterraines des aquifères des altérites et de fissures du socle précambrien. La présente étude a pour objectif d’analyser les propriétés hydrodynamiques des aquif

The clayey fissural fillings associated with N100º-110ºE fractures at the El Berrocal uranium mine (Sierra de Gredos, Spain: characterization, genesis and retention capacity of radioactive and other elements

Directory of Open Access Journals (Sweden)

Pérez del Villar, L.

1993-08-01

Full Text Available The clayey fissural fillings (18O data obtained from the quartz vein and the 2++ phosphate precipitation. The high organic C content in the clay fractions could be due to present biological activity in the clayey fissural filling or to organic acids transported from the topographic surface by the percolating water. In this last case, organie-clay complexes would probbly be formed.En relación con los procesos de migración/retención de los radionucleidos naturales en un medio granítico fisurado se han estudiado los rellenos fisurales arcillosos (18O obtenidos del cuarzo filoniano y de la fracción 2++. El alto contenido en C orgánico de la fracción arcilla de las muestras puede explicarse por la actividad bacteriana actual observada en los rellenos fisurales, o por la presencia de ácidos orgánicos, transportados por las aguas percolantes desde la superficie topográfica. En este último caso, han podido formarse complejos orgánico-arcillosos.

Capturing near-Earth asteroids around Earth

Science.gov (United States)

Hasnain, Zaki; Lamb, Christopher A.; Ross, Shane D.

2012-12-01

The list of detected near-Earth asteroids (NEAs) is constantly growing. NEAs are likely targets for resources to support space industrialization, as they may be the least expensive source of certain needed raw materials. The limited supply of precious metals and semiconducting elements on Earth may be supplemented or even replaced by the reserves floating in the form of asteroids around the solar system. Precious metals make up a significant fraction NEAs by mass, and even one metallic asteroid of ˜1km size and fair enrichment in platinum-group metals would contain twice the tonnage of such metals already harvested on Earth. There are ˜1000 NEAs with a diameter of greater than 1 km. Capturing these asteroids around the Earth would expand the mining industry into an entirely new dimension. Having such resources within easy reach in Earth's orbit could provide an off-world environmentally friendly remedy for impending terrestrial shortages, especially given the need for raw materials in developing nations. In this paper, we develop and implement a conceptually simple algorithm to determine trajectory characteristics necessary to move NEAs into capture orbits around the Earth. Altered trajectories of asteroids are calculated using an ephemeris model. Only asteroids of eccentricity less than 0.1 have been studied and the model is restricted to the ecliptic plane for simplicity. We constrain the time of retrieval to be 10 years or less, based on considerations of the time to return on investment. For the heliocentric phase, constant acceleration is assumed. The acceleration required for transporting these asteroids from their undisturbed orbits to the sphere of influence of the Earth is the primary output, along with the impulse or acceleration necessary to effect capture to a bound orbit once the Earth's sphere of influence is reached. The initial guess for the constant acceleration is provided by a new estimation method, similar in spirit to Edelbaum's. Based on the

Optimal Safety Earthing – Earth Electrode Sizing Using A ...

African Journals Online (AJOL)

In this paper a deterministic approach in the sizing of earth electrode using the permissible touch voltage criteria is presented. The deterministic approach is effectively applied in the sizing of the length of earth rod required for the safe earthing of residential and facility buildings. This approach ensures that the earthing ...

Modeling Earth Albedo for Satellites in Earth Orbit

DEFF Research Database (Denmark)

Bhanderi, Dan; Bak, Thomas

2005-01-01

Many satellite are influences by the Earthøs albedo, though very few model schemes exist.in order to predict this phenomenon. Earth albedo is often treated as noise, or ignored completely. When applying solar cells in the attitude hardware, Earth albedo can cause the attitude estimate to deviate...... with as much as 20 deg. Digital Sun sensors with Earth albedo correction in hardware exist, but are expensive. In addition, albedo estimates are necessary in thermal calculations and power budgets. We present a modeling scheme base4d on Eartht reflectance, measured by NASA's Total Ozone Mapping Spectrometer......, in which the Earth Probe Satellite has recorded reflectivity data daily since mid 1996. The mean of these data can be used to calculate the Earth albedo given the positions of the satellite and the Sun. Our results show that the albedo varies highly with the solar angle to the satellite's field of view...

Earth as an extrasolar planet: Earth model validation using EPOXI earth observations.

Science.gov (United States)

Robinson, Tyler D; Meadows, Victoria S; Crisp, David; Deming, Drake; A'hearn, Michael F; Charbonneau, David; Livengood, Timothy A; Seager, Sara; Barry, Richard K; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Wellnitz, Dennis D

2011-06-01

The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward model can be

Digital Earth - A sustainable Earth

Science.gov (United States)

Mahavir

2014-02-01

All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth.

Low-energy near Earth asteroid capture using Earth flybys and aerobraking

Science.gov (United States)

Tan, Minghu; McInnes, Colin; Ceriotti, Matteo

2018-04-01

Since the Sun-Earth libration points L1 and L2 are regarded as ideal locations for space science missions and candidate gateways for future crewed interplanetary missions, capturing near-Earth asteroids (NEAs) around the Sun-Earth L1/L2 points has generated significant interest. Therefore, this paper proposes the concept of coupling together a flyby of the Earth and then capturing small NEAs onto Sun-Earth L1/L2 periodic orbits. In this capture strategy, the Sun-Earth circular restricted three-body problem (CRTBP) is used to calculate target Lypaunov orbits and their invariant manifolds. A periapsis map is then employed to determine the required perigee of the Earth flyby. Moreover, depending on the perigee distance of the flyby, Earth flybys with and without aerobraking are investigated to design a transfer trajectory capturing a small NEA from its initial orbit to the stable manifolds associated with Sun-Earth L1/L2 periodic orbits. Finally, a global optimization is carried out, based on a detailed design procedure for NEA capture using an Earth flyby. Results show that the NEA capture strategies using an Earth flyby with and without aerobraking both have the potential to be of lower cost in terms of energy requirements than a direct NEA capture strategy without the Earth flyby. Moreover, NEA capture with an Earth flyby also has the potential for a shorter flight time compared to the NEA capture strategy without the Earth flyby.

Tectono-volcanic control of fissure type vents for the 28 Ma Panalillo ignimbrite in the Villa de Reyes Graben, San Luis PotosI, Mexico

International Nuclear Information System (INIS)

Tristan-Gonzalez, Margarito; Labarthe-Hernandez, Guillermo; Aguillon-Robles, Alfredo; Aguirre-DIaz, Gerardo J

2008-01-01

The volcano-tectonic events at the Villa de Reyes Graben (VRG), in the southern Sierra Madre Occidental, Mexico, include 1) a regional NNE fault system developed before 32 Ma, 2) this pre-32 Ma faulting controlled the emplacement of 31.5 Ma dacitic domes, 3) NE faulting at 28 Ma that displaced the 31.5 Ma dacitic domes and formed the VRG, as well as the oblique grabens of Bledos and Enramadas oriented NW, 4) emplacement of Panalillo ignimbrite at 28 Ma filling the VRG and erupting from fissures related to the oblique grabens, and eruption of Placa basalt apparently also from fault-controlled vents.

Tectono-volcanic control of fissure type vents for the 28 Ma Panalillo ignimbrite in the Villa de Reyes Graben, San Luis PotosI, Mexico

Energy Technology Data Exchange (ETDEWEB)

Tristan-Gonzalez, Margarito; Labarthe-Hernandez, Guillermo; Aguillon-Robles, Alfredo [Instituto de Geologia/DES IngenierIa, UASLP, Av. Dr. Manuel Nava 5, Zona Universitaria, C.P. 78240, San Luis PotosI, S.L.P. (Mexico); Aguirre-DIaz, Gerardo J [Centro de Geociencias, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, 76230 (Mexico)], E-mail: mtiistan@uasln.mx, E-mail: ger@geociencias.unam.mx

2008-10-01

The volcano-tectonic events at the Villa de Reyes Graben (VRG), in the southern Sierra Madre Occidental, Mexico, include 1) a regional NNE fault system developed before 32 Ma, 2) this pre-32 Ma faulting controlled the emplacement of 31.5 Ma dacitic domes, 3) NE faulting at 28 Ma that displaced the 31.5 Ma dacitic domes and formed the VRG, as well as the oblique grabens of Bledos and Enramadas oriented NW, 4) emplacement of Panalillo ignimbrite at 28 Ma filling the VRG and erupting from fissures related to the oblique grabens, and eruption of Placa basalt apparently also from fault-controlled vents.

Rare earths

Energy Technology Data Exchange (ETDEWEB)

Cranstone, D A

1979-01-01

Rare earth elements are commonly extracted from the minerals monazite, bastnaesite, and xenotine. New uses for these elements are constantly developing; they have found applications in glass polishing, television tube phosphors, high-strength low-alloy steels, magnets, catalysts, refractory ceramics, and hydrogen sponge alloys. In Canada, rare earths have been produced as byproducts of the uranium mining industry, but there was no production of rare earths in 1978 or 1979. The world sources of and markets for the rare earth elements are discussed.

Evaluation of a fissure sealant program as part of community-based teaching and training.

Science.gov (United States)

van Wyk, Philippus J; Kroon, Jeroen; White, John G

2004-01-01

Since 1995 the Department of Community Dentistry of the University of Pretoria has been involved in the rendering of mobile primary oral health care services to children in the Hammanskraal area of Gauteng, South Africa, as part of their students' community-based training. Mokonyama Primary School was identified as the first school where a primary oral health care service could be rendered. The objective of this study was to evaluate the impact (outcomes) of a fissure sealant program on the dentition status of the school children. Seven years after the implementation of the program, the dentition status of children at Mokonyama was compared with that of a comparable group of children from the same area who were not exposed to the program. The results showed that the decayed, missing, and filled teeth in the primary dentition (dmft) in the six-year-old group in Mokonyama (1.74) did not differ significantly from the dmft (1.43) of the control group (p = 0.49). The decayed, missing, and filled teeth in the permanent dentition (DMFT) of 0.59 for the fifteen-year-old group in Mokonyama, however, differed significantly (p = 0.0001) from the DMFT of the control group (2.38). Fifteen-year-old children in Mokonyama had 75.2 percent fewer caries than their counterparts in the control group.

Stress and psychopathology and its impact on quality of life in chronic anal fissure (CAF) patients.

Science.gov (United States)

Arısoy, Özden; Şengül, Neriman; Çakir, Affan

2017-06-01

Chronic anal fissure (CAF) onset, exacerbation, and impact on quality of life are influenced by a host of psychological, physiological, and social factors. We aimed to investigate the difference in psychopathology and stress between normal and CAF groups. Thirty CAF patients and 20 age-sex matched healthy controls were evaluated for Axis I psychopathology, depression, anxiety, and stress with Hamilton and Hospital Depression-Anxiety Scales, Perceived Stress Scale, and SF-36. With a mean age of 39.47, 83.3% of CAF patients were female. Anxiety-depression and stress scores were all significantly higher and functionality was lower in the CAF group compared to controls (p psychopathology while 50% had a previous psychopathology. Pain (96.7% had pain (VAS = 6.55)) and bleeding (83.3% had bleeding (VAS = 4.14)) severity showed a negative impact on bodily pain and role limitations emotional subscales of SF36. There is a high comorbidity of psychopathology in the CAF patients and depression and anxiety severities show a negative impact on the quality of life. Stress acts as both a triggering and an exacerbating factor in CAF.

Assessment of effectiveness of geologic isolation systems. Analytic modeling of flow in a permeable fissured medium

International Nuclear Information System (INIS)

Strack, O.D.L.

1982-02-01

An analytic model has been developed for two dimensional steady flow through infinite fissured porous media, and is implemented in a computer program. The model is the first, and major, step toward the development of a model with finite boundaries, intended for use as a tool for numerical experiments. These experiments may serve to verify some of the simplifying assumptions made in continuum models and to gain insight in the mechanics of the flow. The model is formulated in terms of complex variables and the analytic functions presented are closed-form expressions obtained from singular Cauchy integrals. An exact solution is given for the case of a single crack in an infinite porous medium. The exact solution is compared with the result obtained by the use of an independent method, which assumes Darcian flow in the crack and models the crack as an inhomogeneity in the permeability, in order to verify the simplifying assumptions. The approximate model is compared with solutions obtained from the above independent method for some cases of intersecting cracks. The agreement is good, provided that a sufficient number of elements are used to model the cracks

ISS EarthKam: Taking Photos of the Earth from Space

Science.gov (United States)

Haste, Turtle

2008-01-01

NASA is involved in a project involving the International Space Station (ISS) and an Earth-focused camera called EarthKam, where schools, and ultimately students, are allowed to remotely program the EarthKAM to take images. Here the author describes how EarthKam was used to help middle school students learn about biomes and develop their…

Rare earth germanates

International Nuclear Information System (INIS)

Bondar', I.A.; Vinogradova, N.V.; Dem'yanets, L.N.

1983-01-01

Rare earth germanates attract close attention both as an independent class of compounds and analogues of a widely spread class of natural and synthetic minerals. The methods of rare earth germanate synthesis (solid-phase, hydrothermal) are considered. Systems on the basis of germanium and rare earth oxides, phase diagrams, phase transformations are studied. Using different chemical analysese the processes of rare earth germanate formation are investigated. IR spectra of alkali and rare earth metal germanates are presented, their comparative analysis being carried out. Crystal structures of the compounds, lattice parameters are studied. Fields of possible application of rare earth germanates are shown

Rare earth sulfates

International Nuclear Information System (INIS)

Komissarova, L.N.; Shatskij, V.M.; Pokrovskij, A.N.; Chizhov, S.M.; Bal'kina, T.I.; Suponitskij, Yu.L.

1986-01-01

Results of experimental works on the study of synthesis conditions, structure and physico-chemical properties of rare earth, scandium and yttrium sulfates, have been generalized. Phase diagrams of solubility and fusibility, thermodynamic and crystallochemical characteristics, thermal stability of hydrates and anhydrous sulfates of rare earths, including normal, double (with cations of alkali and alkaline-earth metals), ternary and anion-mixed sulfates of rare earths, as well as their adducts, are considered. The state of ions of rare earths, scandium and yttrium in aqueous sulfuric acid solutions is discussed. Data on the use of rare earth sulfates are given

Digital Earth – A sustainable Earth

International Nuclear Information System (INIS)

Mahavir

2014-01-01

All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth

Why Earth Science?

Science.gov (United States)

Smith, Michael J.

2004-01-01

This article briefly describes Earth science. The study of Earth science provides the foundation for an understanding of the Earth, its processes, its resources, and its environment. Earth science is the study of the planet in its entirety, how its lithosphere, atmosphere, hydrosphere, and biosphere work together as systems and how they affect…

Earth observation from the manned low Earth orbit platforms

Science.gov (United States)

Guo, Huadong; Dou, Changyong; Zhang, Xiaodong; Han, Chunming; Yue, Xijuan

2016-05-01

The manned low Earth orbit platforms (MLEOPs), e.g., the U.S. and Russia's human space vehicles, the International Space Station (ISS) and Chinese Tiangong-1 experimental space laboratory not only provide laboratories for scientific experiments in a wide range of disciplines, but also serve as exceptional platforms for remote observation of the Earth, astronomical objects and space environment. As the early orbiting platforms, the MLEOPs provide humans with revolutionary accessibility to the regions on Earth never seen before. Earth observation from MLEOPs began in early 1960s, as a part of manned space flight programs, and will continue with the ISS and upcoming Chinese Space Station. Through a series of flight missions, various and a large amount of Earth observing datasets have been acquired using handheld cameras by crewmembers as well as automated sophisticated sensors onboard these space vehicles. Utilizing these datasets many researches have been conducted, demonstrating the importance and uniqueness of studying Earth from a vantage point of MLEOPs. For example, the first, near-global scale digital elevation model (DEM) was developed from data obtained during the shuttle radar topography mission (SRTM). This review intends to provide an overview of Earth observations from MLEOPs and present applications conducted by the datasets collected by these missions. As the ISS is the most typical representative of MLEOPs, an introduction to it, including orbital characteristics, payload accommodations, and current and proposed sensors, is emphasized. The advantages and challenges of Earth observation from MLEOPs, using the ISS as an example, is also addressed. At last, a conclusive note is drawn.

Earth Rotation

Science.gov (United States)

Dickey, Jean O.

1995-01-01

The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

Fissure zeolite mineralization of the intermediate rocks of Central Slovakian neovolcanites; Puklinova zeolitova mineralizacia intermediarnych hornin stredoslovenskych neovulkanitov

Energy Technology Data Exchange (ETDEWEB)

Smal, P [Univerzita Komenskeho v Bratislave, Prirodovedecka fakulta, Katedra mineralogie a petrologie, 84215 Bratislava (Slovakia)

2012-04-25

This contribution summarizes the results of the study of fissure zeolite mineralization at several locations in the intermediate rocks of the Central Slovakian neovolcanites. These locations were monitored: Kremnica, Pila by Zarnovica, Sklene Teplice, Takyl, Banska Stiavnica, Hodrusa-Hamre, Prencov and Brehy by Nova Bana, Biely Vrch and Slatinske Lazy. Zeolites have been identified as follows: laumontite, chabazite, heulandite, stilbite, natrolite and thomsonite. They occurred in simple associations - mainly laumontite with calcite and stilbite from Pila, or natrolite with thomsonit from Kremnica. From the morphological point of view laumontite formed prismatic needle crystals and adhesions according to (100) or it was massive. Chabazite was formed as pseudo-cubic and in a form of interpenetration adhesions. Heulandite featured druses with crystal size up to 4 mm. Analyses focused on crystallo-chemical study to find out the contents of exchangeable cations or of water and try to interpret their influence on the crystal structure. Ca was a dominant cation in all the zeolites except natrolite. Influence of K and of a ratio of Si / Al on structure of laumontite was proved. (author)

Macroanatomical Landmarks Featuring Junctions of Major Sulci and Fissures and Scalp Landmarks Based on the International 10–10 System for Analyzing Lateral Cortical Development of Infants

Directory of Open Access Journals (Sweden)

Daisuke Tsuzuki

2017-07-01

Full Text Available The topographic relationships between the macroanatomical structure of the lateral cortex, including sulci and fissures, and anatomical landmarks on the external surface of the head are known to be consistent. This allows the coregistration of EEG electrodes or functional near-infrared spectroscopy over the scalp with underlying cortical regions. However, limited information is available as to whether the topographic relationships are maintained in rapidly developing infants, whose brains and heads exhibit drastic growth. We used MRIs of infants ranging in age from 3 to 22 months old, and identified 20 macroanatomical landmarks, featuring the junctions of major sulci and fissures, as well as cranial landmarks and virtually determined positions of the international 10-20 and 10-10 systems. A Procrustes analysis revealed developmental trends in changes of shape in both the cortex and head. An analysis of Euclidian distances between selected pairs of cortical landmarks at standard stereotactic coordinates showed anterior shifts of the relative positions of the premotor and parietal cortices with age. Finally, cortical landmark positions and their spatial variability were compared with 10-10 landmark positions. The results indicate that variability in the distribution of each macroanatomical landmark was much smaller than the pitch of the 10-10 landmarks. This study demonstrates that the scalp-based 10-10 system serves as a good frame of reference in infants not only for assessing the development of the macroanatomy of the lateral cortical structure, but also for functional studies of cortical development using transcranial modalities such as EEG and fNIRS.

An Earth-sized planet with an Earth-like density

DEFF Research Database (Denmark)

Pepe, Francesco; Cameron, Andrew Collier; Latham, David W.

2013-01-01

significantly larger than the Earth. Recently, the planet Kepler-78b was discovered(8) and found to have a radius of only 1.16R(circle plus). Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth...

Transection of inferior orbital fissure contents for improved access and visibility in orbital surgery.

Science.gov (United States)

Ricketts, Sophie; Chew, Hall F; Sunderland, Ian R P; Kiss, Alex; Fialkov, Jeffrey A

2014-03-01

Selective inferior orbital fissure (IOF) content transection for the purpose of surgical access to the posterior orbital floor is a technique that facilitates visualization of the posterior bony ledges of traumatic orbital floor defects. It also has potential advantages in achieving stable placement of reconstructive materials. Although not new, the surgical technique has not yet been described, and the morbidity of the technique has not been quantified. This article describes the procedure and assesses the morbidity specific to the division of related neural structures. The technique and surgical anatomy are described and illustrated with intraoperative photographs. Postoperative assessment of neural structures relevant to the division of IOF contents is performed. These values are compared with the nonoperated side to evaluate the morbidity of the technique. The technique, which is consistently used by the senior author in the repair of orbital floor defects with very small posterior ledges or which extend to and involve the IOF, facilitates better visualization of the posterior ledge and posterolateral ledge in such cases. Surgical outcomes including facial sensation and lacrimal function on the operated side remain within the reference range and are not significantly different when compared with the contralateral nonoperated side. Selective IOF transection aids in the direct visualization of the posterior bony ledges in the repair of posterior orbital floor defects. It therefore may facilitate the placement of reconstructive materials on bony ledges circumferentially, providing stable reconstruction, potentially reducing implant-related complications without causing increased morbidity.

EarthLabs - Investigating Hurricanes: Earth's Meteorological Monsters

Science.gov (United States)

McDaris, J. R.; Dahlman, L.; Barstow, D.

2007-12-01

Earth science is one of the most important tools that the global community needs to address the pressing environmental, social, and economic issues of our time. While, at times considered a second-rate science at the high school level, it is currently undergoing a major revolution in the depth of content and pedagogical vitality. As part of this revolution, labs in Earth science courses need to shift their focus from cookbook-like activities with known outcomes to open-ended investigations that challenge students to think, explore and apply their learning. We need to establish a new model for Earth science as a rigorous lab science in policy, perception, and reality. As a concerted response to this need, five states, a coalition of scientists and educators, and an experienced curriculum team are creating a national model for a lab-based high school Earth science course named EarthLabs. This lab course will comply with the National Science Education Standards as well as the states' curriculum frameworks. The content will focus on Earth system science and environmental literacy. The lab experiences will feature a combination of field work, classroom experiments, and computer access to data and visualizations, and demonstrate the rigor and depth of a true lab course. The effort is being funded by NOAA's Environmental Literacy program. One of the prototype units of the course is Investigating Hurricanes. Hurricanes are phenomena which have tremendous impact on humanity and the resources we use. They are also the result of complex interacting Earth systems, making them perfect objects for rigorous investigation of many concepts commonly covered in Earth science courses, such as meteorology, climate, and global wind circulation. Students are able to use the same data sets, analysis tools, and research techniques that scientists employ in their research, yielding truly authentic learning opportunities. This month-long integrated unit uses hurricanes as the story line by

Red-emitting alkaline-earth rare-earth pentaoxometallates powders ...

Indian Academy of Sciences (India)

Moisture-insensitive metal carboxylates that are mostly liquids at room temperature have been first applied to ... alkaline-earth ion, or possibly even a rare-earth ion and alkali metal ... sion spectra of the powders were recorded on a fluorescent.

Earth - South America (first frame of Earth Spin Movie)

Science.gov (United States)

1990-01-01

This color image of the Earth was obtained by Galileo at about 6:10 a.m. Pacific Standard Time on Dec. 11, 1990, when the spacecraft was about 1.3 million miles from the planet during the first of two Earth flybys on its way to Jupiter. The color composite used images taken through the red, green and violet filters. South America is near the center of the picture, and the white, sunlit continent of Antarctica is below. Picturesque weather fronts are visible in the South Atlantic, lower right. This is the first frame of the Galileo Earth spin movie, a 500- frame time-lapse motion picture showing a 25-hour period of Earth's rotation and atmospheric dynamics.

Building a Dashboard of the Planet with Google Earth and Earth Engine

Science.gov (United States)

Moore, R. T.; Hancher, M.

2016-12-01

In 2005 Google Earth, a popular 3-D virtual globe, was first released. Scientists immediately recognized how it could be used to tell stories about the Earth. From 2006 to 2009, the "Virtual Globes" sessions of AGU included innovative examples of scientists and educators using Google Earth, and since that time it has become a commonplace tool for communicating scientific results. In 2009 Google Earth Engine, a cloud-based platform for planetary-scale geospatial analysis, was first announced. Earth Engine was initially used to extract information about the world's forests from raw Landsat data. Since then, the platform has proven highly effective for general analysis of georeferenced data, and users have expanded the list of use cases to include high-impact societal issues such as conservation, drought, disease, food security, water management, climate change and environmental monitoring. To support these use cases, the platform has continuously evolved with new datasets, analysis functions, and user interface tools. This talk will give an overview of the latest Google Earth and Earth Engine functionality that allow partners to understand, monitor and tell stories about of our living, breathing Earth. https://earth.google.com https://earthengine.google.com

Inaugeral lecture - Meteorite impacts on Earth and on the Earth ...

African Journals Online (AJOL)

There is some controversial evidence for the theory that the first life on Earth itself may have been transported here on meteorites from Mars. The possibility of a major meteorite impact on Earth in the near future emphasizes the dramatic nature of these recent discoveries, which are having deep impacts in the Earth sciences ...

The sealing of second mandibular temporary molar pits and fissure with the laser of Nd: YAG, phosphoric acid and the glass ionomer cement

International Nuclear Information System (INIS)

Toda, Maria Aparecida

2003-01-01

The main of our study was to check the sealing of second mandibular temporary molar pits and fissure, in vitro, with the laser of Nd: YAG, phosphoric acid at 37% and the glass ionomer cement (CIV, Fuji IX GC).The proposal was to check the structural morphologic changes in the laser irradiation upon the enamel surface to watch the pits and fissure sealing with the glass ionomer cement use after the laser irradiation and to verify the efficiency of the 'double conditioning' (phosphoric acid + Nd: YAG). At the same time we watch the evolution of the temperature in the pulp chamber's inside. Our desire was to achieve a therapeutic alternative technic to prevent the dental caries. The Nd: YAG laser parameters were the same: 79 mJ of energy per pulse; frequency of 5 Hz; mean power of 0,4 W; optical fiber on contact of 320 μm diameter; fluency of 99,52 J/ cm 2 , assuming that the only differential was the time of the laser application on the enamel surface. The samples were prepared with this way: Laser Nd: YAG (53 second) + acid + CIV (Fuji IX); Laser Nd: YAG (53 s); Laser Nd: YAG (20 s + 20 s) + acid + CIV; Laser Nd: YAG (20 s + 20 s); Acid + CIV; Control. Through the scanning electron microscopy (MEV) we noticed fusion and resolidification regions due to the laser irradiation and a better adaptation of the glass ionomer cement when we did the 'double conditioning'. Concerning the temperature increase we can conclude that the echeloned period was the best recommended because the temperature was found in a pattern that would not cause any damage to the dental pulp. For future studies we suggest a longer relaxing time between the laser irradiation, a comparative study of this method with other lasers, the use of other sealing materials and the study with the permanent teeth. (author)

Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

Science.gov (United States)

West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID

2011-09-27

Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.

The Lifeworld Earth and a Modelled Earth

Science.gov (United States)

Juuti, Kalle

2014-01-01

The goal of this paper is to study the question of whether a phenomenological view of the Earth could be empirically endorsed. The phenomenological way of thinking considers the Earth as a material entity, but not as an object as viewed in science. In the learning science tradition, tracking the process of the conceptual change of the shape of the…

Characterization and modelling of fluid flows in fissured and fractured media. relation with hydrothermal alterations and paleo-stress quantification; Caracterisation et modelisation des ecoulements fluides en milieu fissure. relation avec les alterations hydrothermales et quantification des paleocontraintes

Energy Technology Data Exchange (ETDEWEB)

Sausse, J.

1998-10-15

In all materials (rocks, concretes, ceramics,...), the presence of fractures at different scales implies high permeability and often oriented fluid flows. These fluid circulations in fractures induce more or less intense fluid-rock interactions with mineral crystallisation and/or dissolution. These phenomena directly depend on the nature of the fluids and the rocks, the physical and chemical properties of the media and the rate of fluid renewal (permeabilities). Usually, the development of such alterations leads to a massive sealing of the fractures (vein alterations) and of the fissures (fluid inclusion planes and microcracks, pervasive alteration). Therefore, their study brings us precious indications for the understanding of the mechanisms of fluid migrations in fossil systems. A geometrical study of the fracture systems at micro or macroscopic scales, based on the spatial distribution of sealing minerals, is applied to two different granites: the Soultz-sous-Foret granite (Bas-Rhin, France) and the Brezouard granite (Vosges, France). At the macroscopic scale, a new graphical method is proposed in order to study drilling data (Soultz granite). It allows to identify the presence of three independent mineral associations (quartz - illite, calcite-chlorite and hematite) in independent fracture systems characterised by a specific 3D geometry and hydraulic properties. These three types of vein alteration correspond to distinct and non contemporaneous fluid percolations. At the microscopic scale, the reconstitution of crack opening - fluid percolation - crack sealing stages is delicate. However, the study of their geometrical characteristics (orientations, radius, volume densities) and thereby the quantification of their porosities, exchange surfaces and permeabilities, allow to identify their respective roles in the fluid propagation. These microstructures, which are very numerous in granites, imply high but variable matrix permeabilities. This has been confirmed by

Atmospheric acceleration and Earth-expansion deceleration of the Earth rotation

Directory of Open Access Journals (Sweden)

Wenbin Shen

2017-11-01

Full Text Available Previous studies suggest that tidal friction gives rise to the secular deceleration of the Earth rotation by a quantity of about 2.25 ms/cy. Here we just consider additional contributions to the secular Earth rotation deceleration. Atmospheric solar semi-diurnal tide has a small amplitude and certain amount of phase lead. This periodic global air-mass excess distribution exerts a quasi-constant torque to accelerate the Earth's spin rotation. Using an updated atmospheric tide model, we re-estimate the amounts of this atmospheric acceleration torque and corresponding energy input, of which the associated change rate in LOD (length of day is −0.1 ms/cy. In another aspect, evidences from space-geodesy and sea level rise observations suggest that Earth expands at a rate of 0.35 mm/yr in recent decades, which gives rise to the increase of LOD at rate of 1.0 ms/cy. Hence, if the previous estimate due to the tidal friction is correct, the secular Earth rotation deceleration due to tidal friction and Earth expansion should be 3.15 ms/cy.

Rare earths

International Nuclear Information System (INIS)

1984-01-01

The conference was held from September 12 to 13, 1984 in Jetrichovice, Czechoslovakia. The participants heard 16 papers of which 4 were inputted in INIS. These papers dealt with industrial separation processes of rare earths, the use of chemical methods of separation from the concentrate of apatite and bastnesite, the effect of the relative permittivity of solvents in the elution of rare earth elements from a cation exchanger, and the determination of the content of different rare earth elements using X-ray fluorescence analysis and atomic absorption spectroscopy. (E.S.)

Early Earth(s) Across Time and Space

Science.gov (United States)

Mojzsis, S.

2014-04-01

The geochemical and cosmochemical record of our solar system is the baseline for exploring the question: "when could life appear on a world similar to our own?" Data arising from direct analysis of the oldest terrestrial rocks and minerals from the first 500 Myr of Earth history - termed the Hadean Eon - inform us about the timing for the establishment of a habitable silicate world. Liquid water is the key medium for life. The origin of water, and its interaction with the crust as revealed in the geologic record, guides our exploration for a cosmochemically Earth-like planets. From the time of primary planetary accretion to the start of the continuous rock record on Earth at ca. 3850 million years ago, our planet experienced a waning bolide flux that partially or entirely wiped out surface rocks, vaporized oceans, and created transient serpentinizing atmospheres. Arguably, "Early Earths" across the galaxy may start off as ice planets due to feeble insolation from their young stars, occasionally punctuated by steam atmospheres generated by cataclysmic impacts. Alternatively, early global environments conducive to life spanned from a benign surface zone to deep into crustal rocks and sediments. In some scenarios, nascent biospheres benefit from the exogenous delivery of essential bio-elements via leftovers of accretion, and the subsequent establishment of planetary-scale hydrothermal systems. If what is now known about the early dynamical regime of the Earth serves as any measure of the potential habitability of worlds across space and time, several key boundary conditions emerge. These are: (i) availability and long-term stability of liquid water; (ii) presence of energy resources; (iii) accessibility of organic raw materials; (iv) adequate inventory of radioisotopes to drive internal heating; (v) gross compositional parameters such as mantle/core mass ratio, and (vi) P-T conditions at or near the surface suitable for sustaining biological activity. Life could

Approche numérique et quantitative de l'étude sur clichés aériens de la fracturation des réservoirs en roches fissurées Numerical and Quantitative Approach to Investigating Fracture Maps of Fissured Reservoirs from Airphotos

Directory of Open Access Journals (Sweden)

Razack M.

2006-11-01

Full Text Available Dans le cadre de la détermination de la structure des réservoirs en roches fissurées, une méthodologie de traitement numérique et quantitative de la fractu-ration relevée sur clichés aériens a été mise au point. La numérisation du relevé est obtenue par digitalisation sur un lecteur de courbes. Cette information est ensuite traitée à l'aide d'un algorithme (programme RAFRAC qui permet d'identifier numériquement la fracturation par un ensemble de para-mètres élémentaires (orientation, longueur , densité... à partir desquels il devient possible de procéder à une analyse approfondie du champ de fractures considéré. Un exemple d'application est présenté à propos de l'étude de la fracturation d'une zone à structure tabulaire (Causse du Larzac. Ces premiers résultats tendent à mettre en évidence une double nature mathématique de l'information analysée aléatoire d'une part, déterministe d'autre part. On montre également, à partir de la théorie desvariables régionalisées, que la fracturation suit une certaine logique dans sa répartition spatiale. Par ailleurs une organisation des familles de fractures a pu être mise en évidence, sur laquelle la structure géométrique du réservoir sous-jacent s'ajuste de façon très proche. As part of efforts ta determine the structure of reservoirs in fissured rocks, a numerical and quantitative processing methodology has been developed for mapping fractures with airphotos. The survey is digitized on a curve reader. This data is then processed by means of an algorithm (RAFRAC program sa as ta numerically identify fracturing by a set of elementary parameters (direction, length, density, etc. which con be used ta make an in-depth analysis of the fracture field being considered. A sample application is described having ta do with the surveying of the fracturing in a tabular structure (Causse plateau of Larzac. These initial results tend to reveol a dual mathematical nature

Rare earths and rare earth alloys electrolytic preparation process and device for this process

International Nuclear Information System (INIS)

Seon, F.; Barthole, G.

1986-01-01

Electrolysis of a molten salt of rare earth or rare earth alloy for preparation of the metal or alloy is described. The molten salt bath comprises at least a rare earth chloride, at least an alkaline or alkaline earth chloride and at least an alkaline or alkaline earth fluoride [fr

Genome-wide association studies of pit-and-fissure- and smooth-surface caries in permanent dentition.

Science.gov (United States)

Zeng, Z; Shaffer, J R; Wang, X; Feingold, E; Weeks, D E; Lee, M; Cuenco, K T; Wendell, S K; Weyant, R J; Crout, R; McNeil, D W; Marazita, M L

2013-05-01

While genetics clearly influences dental caries risk, few caries genes have been discovered and validated. Recent studies have suggested differential genetic factors for primary dentition caries and permanent dentition caries, as well as for pit-and-fissure- (PF) and smooth- (SM) surface caries. We performed separate GWAS for caries in permanent-dentition PF surfaces (1,017 participants, adjusted for age, sex, and the presence of Streptococcus mutans) and SM surfaces (1,004 participants, adjusted for age, education group, and the presence of Streptococcus mutans) in self-reported whites (ages 14 to 56 yrs). Caries scores were derived based on visual assessment of each surface of each tooth; more than 1.2 million SNPs were either successfully genotyped or imputed and were tested for association. Two homologous genes were suggestively associated: BCOR (Xp11.4) in PF-surface caries (p value = 1.8E-7), and BCORL1 (Xq26.1) in SM-surface caries (p value = 1.0E-5). BCOR mutations cause oculofaciocardiodental syndrome, a Mendelian disease involving multiple dental anomalies. Associations of other plausible cariogenesis genes were also observed for PF-surface caries (e.g., INHBA, p value = 6.5E-6) and for SM-surface caries (e.g., CXCR1 and CXCR2, p value = 1.9E-6). This study supports the notion that genes differentially affect cariogenesis across the surfaces of the permanent dentition, and nominates several novel genes for investigation.

Does the high-intensity zone (HIZ) of lumbar Intervertebral discs always represent an annular fissure?

Energy Technology Data Exchange (ETDEWEB)

Shan, Zhi; Chen, Huanhuan; Liu, Junhui; Ren, Hong; Zhang, Xuyang; Zhao, Fengdong [Zhejiang University, Department of Orthopaedics, Sir Run Run Shaw Hospital, School of Medicine, Hangzhou (China)

2017-03-15

The aim of this study was to examine high-intensity zone (HIZ) characteristics on both T1- and T2-weighted sagittal magnetic resonance (MR) images, and to reveal their exact nature. Seventy-three patients with low back pain and HIZs (identified on T2-weighted images) were included. Patients, aged 25-80 years (mean 51), were divided into two groups: the 'single-HIZ' group exhibited HIZs only on T2-weighted images, while the 'dual-HIZ' group exhibited HIZs on both T2-weighted and T1-weighted images. Tissue corresponding to the HIZ was harvested from surgery for analysis. Eighty-two discs were studied, from 39 patients with single HIZs, 30 with dual HIZs, and four with both in the posterior annulus. HIZ volume, volume ratio, and signal intensity on T2-weighted images from the dual-HIZ group were significantly greater. Surgery was able to successfully restore patients' ability in both groups, while conservative treatments were less effective for patients with dual HIZs. Histology revealed outer annular fissures invaded by granulation tissue in the single-HIZ group. In dual-HIZ discs, Von Kossa staining and CT scans showed more calcified or ossified lesions (94.1 vs. 0 %, P<0.001), and chemical analysis showed significantly higher calcium content. HIZs on both T2- and T1-weighted images represent calcified tissue, possibly from a vertebral endplate. A new concept of dual HIZ should be defined. (orig.)

The "Earth Physics" Workshops Offered by the Earth Science Education Unit

Science.gov (United States)

Davies, Stephen

2012-01-01

Earth science has a part to play in broadening students' learning experience in physics. The Earth Science Education Unit presents a range of (free) workshops to teachers and trainee teachers, suggesting how Earth-based science activities, which show how we understand and use the planet we live on, can easily be slotted into normal science…

Modeling of the Earth's gravity field using the New Global Earth Model (NEWGEM)

Science.gov (United States)

Kim, Yeong E.; Braswell, W. Danny

1989-01-01

Traditionally, the global gravity field was described by representations based on the spherical harmonics (SH) expansion of the geopotential. The SH expansion coefficients were determined by fitting the Earth's gravity data as measured by many different methods including the use of artificial satellites. As gravity data have accumulated with increasingly better accuracies, more of the higher order SH expansion coefficients were determined. The SH representation is useful for describing the gravity field exterior to the Earth but is theoretically invalid on the Earth's surface and in the Earth's interior. A new global Earth model (NEWGEM) (KIM, 1987 and 1988a) was recently proposed to provide a unified description of the Earth's gravity field inside, on, and outside the Earth's surface using the Earth's mass density profile as deduced from seismic studies, elevation and bathymetric information, and local and global gravity data. Using NEWGEM, it is possible to determine the constraints on the mass distribution of the Earth imposed by gravity, topography, and seismic data. NEWGEM is useful in investigating a variety of geophysical phenomena. It is currently being utilized to develop a geophysical interpretation of Kaula's rule. The zeroth order NEWGEM is being used to numerically integrate spherical harmonic expansion coefficients and simultaneously determine the contribution of each layer in the model to a given coefficient. The numerically determined SH expansion coefficients are also being used to test the validity of SH expansions at the surface of the Earth by comparing the resulting SH expansion gravity model with exact calculations of the gravity at the Earth's surface.

Beautiful Earth: Inspiring Native American students in Earth Science through Music, Art and Science

Science.gov (United States)

Casasanto, V.; Rock, J.; Hallowell, R.; Williams, K.; Angell, D.; Beautiful Earth

2011-12-01

The Beautiful Earth program, awarded by NASA's Competitive Opportunities in Education and Public Outreach for Earth and Space Science (EPOESS), is a live multi-media performance at partner science centers linked with hands-on workshops featuring Earth scientists and Native American experts. It aims to inspire, engage and educate diverse students in Earth science through an experience of viewing the Earth from space as one interconnected whole, as seen through the eyes of astronauts. The informal education program is an outgrowth of Kenji Williams' BELLA GAIA Living Atlas Experience (www.bellagaia.com) performed across the globe since 2008 and following the successful Earth Day education events in 2009 and 2010 with NASA's DLN (Digital Learning Network) http://tinyurl.com/2ckg2rh. Beautiful Earth takes a new approach to teaching, by combining live music and data visualizations, Earth Science with indigenous perspectives of the Earth, and hands-on interactive workshops. The program will utilize the emotionally inspiring multi-media show as a springboard to inspire participants to learn more about Earth systems and science. Native Earth Ways (NEW) will be the first module in a series of three "Beautiful Earth" experiences, that will launch the national tour at a presentation in October 2011 at the MOST science museum in collaboration with the Onandaga Nation School in Syracuse, New York. The NEW Module will include Native American experts to explain how they study and conserve the Earth in their own unique ways along with hands-on activities to convey the science which was seen in the show. In this first pilot run of the module, 110 K-12 students with faculty and family members of the Onandaga Nations School will take part. The goal of the program is to introduce Native American students to Earth Sciences and STEM careers, and encourage them to study these sciences and become responsible stewards of the Earth. The second workshop presented to participants will be the

Raising awareness for research on earth walls, and earth scientific aspects

Science.gov (United States)

van den Ancker, Hanneke; Jungerius, Pieter Dirk; Baas, Henk; Groenewoudt, Bert; Peen, Charlotte

2013-04-01

A conference to raise awareness In the Netherlands, little research on earth walls has been done. To improve attention for earth walls, a number of organisations, including Geoheritage NL, organized a conference at the RCE, the Cultural Heritage Agency of the Netherlands. The conference* presented a state-of-the-art of research done. The book with the presentations, and extra case studies added, was published in December 2012. The book concludes with a research action list, including earth science research, and can be downloaded freely from the internet. It has English summaries. The earth science aspects Historical earth walls do not only add cultural value to a landscape, but also geodiversity value. Apart from geomorphological aspects, the walls contain information about past land- and climate conditions: - They cover up a former topography, a past landscape. A relevant source of scientific information where lands are levelled, as is the case in many parts of The Netherlands; - The soil formation under the earth wall is a reference soil. The soil formation in the top of the wall gives insight in the rate of soil formation in relationship with the age and parent material of the wall; - The soil profiles of different age have ecological significance. Older walls with a more pronounced soil formation often hold forest flora that has disappeared from the surrounding environment, such as historical bush or tree species, autogenetic DNA material or a specific soil fauna; - The materials in the earth walls tell about the process of wall-building. Paleosols and sedimentary structures in the earth walls, in the gullies and colluvial fans along the walls contain information about past land management and climate. - The eroded appearance of the earth walls is part of their history, and contain information about past management and land conditions, has ecological relevance, for example for insects, and is often visually more interesting. Insight in the rates of erosion are

Extraction of rare earths from iron-rich rare earth deposits

OpenAIRE

Bisaka, K.; Thobadi, I.C.; Pawlik, C.

2017-01-01

Rare earth metals are classified as critical metals by the United Nations, as they have found wide application in the fabrication of magnets, particularly those used in green energy technologies which mitigate global warming. Processing of ores containing rare earth elements is complex, and differs according to the nature of each ore. In the conventional process, run of mine (ROM) ores are processed in a physical separation plant to produce a concentrate from which rare earth elements are ext...

China's rare-earth industry

Science.gov (United States)

Tse, Pui-Kwan

2011-01-01

Introduction China's dominant position as the producer of over 95 percent of the world output of rare-earth minerals and rapid increases in the consumption of rare earths owing to the emergence of new clean-energy and defense-related technologies, combined with China's decisions to restrict exports of rare earths, have resulted in heightened concerns about the future availability of rare earths. As a result, industrial countries such as Japan, the United States, and countries of the European Union face tighter supplies and higher prices for rare earths. This paper briefly reviews China's rare-earth production, consumption, and reserves and the important policies and regulations regarding the production and trade of rare earths, including recently announced export quotas. The 15 lanthanide elements-lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium (atomic numbers 57-71)-were originally known as the rare earths from their occurrence in oxides mixtures. Recently, some researchers have included two other elements-scandium and yttrium-in their discussion of rare earths. Yttrium (atomic number 39), which lies above lanthanum in transition group III of the periodic table and has a similar 3+ ion with a noble gas core, has both atomic and ionic radii similar in size to those of terbium and dysprosium and is generally found in nature with lanthanides. Scandium (atomic number 21) has a smaller ionic radius than yttrium and the lanthanides, and its chemical behavior is intermediate between that of aluminum and the lanthanides. It is found in nature with the lanthanides and yttrium. Rare earths are used widely in high-technology and clean-energy products because they impart special properties of magnetism, luminescence, and strength. Rare earths are also used in weapon systems to obtain the same properties.

Mission to Planet Earth

International Nuclear Information System (INIS)

Wilson, G.S.; Backlund, P.W.

1992-01-01

Mission to Planet Earth (MTPE) is NASA's concept for an international science program to produce the understanding needed to predict changes in the earth's environment. NASA and its interagency and international partners will place satellites carrying advanced sensors in strategic earth orbits to gather multidisciplinary data. A sophisticated data system will process and archive an unprecedented amount of information about the earth and how it works as a system. Increased understanding of the earth system is a basic human responsibility, a prerequisite to informed management of the planet's resources and to the preservation of the global environment. 8 refs

Mission to Planet Earth

Science.gov (United States)

Tilford, Shelby G.; Asrar, Ghassem; Backlund, Peter W.

1994-01-01

Mission to Planet Earth (MTPE) is NASA's concept for an international science program to produce the understanding needed to predict changes in the Earth's environment. NASA and its interagency and international partners will place satellites carrying advanced sensors in strategic Earth orbits to gather multidisciplinary data. A sophisticated data system will process and archive an unprecedented amount of information about the Earth and how it works as a system. Increased understanding of the Earth system is a basic human responsibility, a prerequisite to informed management of the planet's resources and to the preservation of the global environment.

EarthServer: Cross-Disciplinary Earth Science Through Data Cube Analytics

Science.gov (United States)

Baumann, P.; Rossi, A. P.

2016-12-01

The unprecedented increase of imagery, in-situ measurements, and simulation data produced by Earth (and Planetary) Science observations missions bears a rich, yet not leveraged potential for getting insights from integrating such diverse datasets and transform scientific questions into actual queries to data, formulated in a standardized way.The intercontinental EarthServer [1] initiative is demonstrating new directions for flexible, scalable Earth Science services based on innovative NoSQL technology. Researchers from Europe, the US and Australia have teamed up to rigorously implement the concept of the datacube. Such a datacube may have spatial and temporal dimensions (such as a satellite image time series) and may unite an unlimited number of scenes. Independently from whatever efficient data structuring a server network may perform internally, users (scientist, planners, decision makers) will always see just a few datacubes they can slice and dice.EarthServer has established client [2] and server technology for such spatio-temporal datacubes. The underlying scalable array engine, rasdaman [3,4], enables direct interaction, including 3-D visualization, common EO data processing, and general analytics. Services exclusively rely on the open OGC "Big Geo Data" standards suite, the Web Coverage Service (WCS). Conversely, EarthServer has shaped and advanced WCS based on the experience gained. The first phase of EarthServer has advanced scalable array database technology into 150+ TB services. Currently, Petabyte datacubes are being built for ad-hoc and cross-disciplinary querying, e.g. using climate, Earth observation and ocean data.We will present the EarthServer approach, its impact on OGC / ISO / INSPIRE standardization, and its platform technology, rasdaman.References: [1] Baumann, et al. (2015) DOI: 10.1080/17538947.2014.1003106 [2] Hogan, P., (2011) NASA World Wind, Proceedings of the 2nd International Conference on Computing for Geospatial Research

Towards Big Earth Data Analytics: The EarthServer Approach

Science.gov (United States)

Baumann, Peter

2013-04-01

Big Data in the Earth sciences, the Tera- to Exabyte archives, mostly are made up from coverage data whereby the term "coverage", according to ISO and OGC, is defined as the digital representation of some space-time varying phenomenon. Common examples include 1-D sensor timeseries, 2-D remote sensing imagery, 3D x/y/t image timeseries and x/y/z geology data, and 4-D x/y/z/t atmosphere and ocean data. Analytics on such data requires on-demand processing of sometimes significant complexity, such as getting the Fourier transform of satellite images. As network bandwidth limits prohibit transfer of such Big Data it is indispensable to devise protocols allowing clients to task flexible and fast processing on the server. The EarthServer initiative, funded by EU FP7 eInfrastructures, unites 11 partners from computer and earth sciences to establish Big Earth Data Analytics. One key ingredient is flexibility for users to ask what they want, not impeded and complicated by system internals. The EarthServer answer to this is to use high-level query languages; these have proven tremendously successful on tabular and XML data, and we extend them with a central geo data structure, multi-dimensional arrays. A second key ingredient is scalability. Without any doubt, scalability ultimately can only be achieved through parallelization. In the past, parallelizing code has been done at compile time and usually with manual intervention. The EarthServer approach is to perform a samentic-based dynamic distribution of queries fragments based on networks optimization and further criteria. The EarthServer platform is comprised by rasdaman, an Array DBMS enabling efficient storage and retrieval of any-size, any-type multi-dimensional raster data. In the project, rasdaman is being extended with several functionality and scalability features, including: support for irregular grids and general meshes; in-situ retrieval (evaluation of database queries on existing archive structures, avoiding data

Earth

CERN Document Server

Carter, Jason

2017-01-01

This curriculum-based, easy-to-follow book teaches young readers about Earth as one of the eight planets in our solar system in astronomical terms. With accessible text, it provides the fundamental information any student needs to begin their studies in astronomy, such as how Earth spins and revolves around the Sun, why it's uniquely suitable for life, its physical features, atmosphere, biosphere, moon, its past, future, and more. To enhance the learning experience, many of the images come directly from NASA. This straightforward title offers the fundamental information any student needs to sp

Normal Fault and Tensile Fissure Network Development Around an Off-Axis Silica-Rich Volcanic Dome of the Alarcon Rise, Southern Gulf of California

Science.gov (United States)

Contreras, J.; Vega-Ramirez, L. A.; Spelz, R. M.; Portner, R. A.; Clague, D. A.

2017-12-01

The Monterey Bay Aquarium Research Institute collected in 2012 and 2015 high-resolution (1 m horizontal/0.2 m vertical) bathymetry data in the southern Gulf of California using an autonomous underwater vehicle (AUV) that bring to light an extensive array of normal faults and fissures cutting lava domes and smaller volcanic cones, pillow mounds and lava sheet flows of variable compositions along the Alarcon rise. Active faulting and fissure growth in the transition between the neovolcanic zone and adjacent axial summit trough, in a 6.9 x 1.5 km2 area at the NE segment of the rise, developed at some point between 6 Ka B.P. (14C) and the present time. We performed a population analysis of fracture networks imaged by the AUV that reveal contrasting scaling attributes between mode I (opening) and mode III (shearing) extensional structures. Opening-mode fractures are spatially constrained to narrow bands 400 m wide. The youngest set developed on pillow lavas 800 yr old (14C) of the neovolcanic zone. Regions of normal fault propagation by anti-plane shearing alternate with the tensile-fracture growth areas. This provides evidence for permutations in space of the stress field across the ridge axis. Moreover, fault-length frequency plots for both fracture networks show that opening-mode fractures are best fit using an exponential relationship whereas normal faults are best fit using a power-law relationship. These size distributions indicate tensile fractures rapidly reached a saturated state in which large fractures (102 m) accommodate most of the strain and appear to be constrained to a thin mechanical/thermal layer. Faults, by contrast, have slowly evolved to a state of self-organization characterized by growth by linkage with neighboring faults in the strike direction forming fault arrays with a maximum length of 2km. We also analyzed the development of faults in the vicinity of an off-axis rhyolitic dome. We find that faults have asymmetric, half-restricted slip

Influence of slip-surface geometry on earth-flow deformation, Montaguto earth flow, southern Italy

Science.gov (United States)

Guerriero, L.; Coe, Jeffrey A.; Revellio, P.; Grelle, G.; Pinto, F.; Guadagno, F.

2016-01-01

We investigated relations between slip-surface geometry and deformational structures and hydrologic features at the Montaguto earth flow in southern Italy between 1954 and 2010. We used 25 boreholes, 15 static cone-penetration tests, and 22 shallow-seismic profiles to define the geometry of basal- and lateral-slip surfaces; and 9 multitemporal maps to quantify the spatial and temporal distribution of normal faults, thrust faults, back-tilted surfaces, strike-slip faults, flank ridges, folds, ponds, and springs. We infer that the slip surface is a repeating series of steeply sloping surfaces (risers) and gently sloping surfaces (treads). Stretching of earth-flow material created normal faults at risers, and shortening of earth-flow material created thrust faults, back-tilted surfaces, and ponds at treads. Individual pairs of risers and treads formed quasi-discrete kinematic zones within the earth flow that operated in unison to transmit pulses of sediment along the length of the flow. The locations of strike-slip faults, flank ridges, and folds were not controlled by basal-slip surface topography but were instead dependent on earth-flow volume and lateral changes in the direction of the earth-flow travel path. The earth-flow travel path was strongly influenced by inactive earth-flow deposits and pre-earth-flow drainages whose positions were determined by tectonic structures. The implications of our results that may be applicable to other earth flows are that structures with strikes normal to the direction of earth-flow motion (e.g., normal faults and thrust faults) can be used as a guide to the geometry of basal-slip surfaces, but that depths to the slip surface (i.e., the thickness of an earth flow) will vary as sediment pulses are transmitted through a flow.

Rare earth octacyanomolybdates(4)

International Nuclear Information System (INIS)

Zubritskaya, D.I.; Sergeeva, A.N.; Pisak, Yu.V.

1980-01-01

Optimal conditions for synthesis of rare-earth octacyanomolybdates(4) of the Ln 4 [Mo(CN) 8 ] 3 xnH 2 O composition (where Ln is a rare-earth element, other than Pr, Pm, Lu, Tb) have been worked out. The synthesis has been accomplished by neutralization with octacianomolybdic acid with rare-earth carbonates. The composition and structure of the compounds synthesized have been studied by infrared-spectroscopy. It has been established that rare-earth octacyanomolybdates(4) form three isostructural groups

Rare earths as a future resource

International Nuclear Information System (INIS)

Cornell, D.H.

1988-01-01

The fourteen rare earth or lanthanide elements have recently emerged as an important natural resource because of the rapidly growing demand in the electronic, chemical and metallurgical industries. The Symposium on rare earth elements as a future resource presented a multidisciplinary review of rare earth chemistry, geology, beneficiation, industrial applications and marketing. Papers by experts in many fields were presented on the following topics: chemical properties of the rare earth elements; the analysis of rare earth elements and minerals; beneficiation and extraction of rare earth elements; economic geochemistry and mineralogy of rare earths; present industrial uses of rare earth elements; the role of rare earth elements in high-temperature superconductors; the technical application of high-temperature superconductors; supply and demand for rare earth products - now and in the future, and the geology of rare earth deposits

Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons

International Nuclear Information System (INIS)

Chevalier, G.; Chevalier, G.; Sinatra, S.T.; Oschman, J.L.; Sokal, K.; Sokal, P.

2012-01-01

Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and un wellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits including better sleep and reduced pain from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance

Next-generation Digital Earth.

Science.gov (United States)

Goodchild, Michael F; Guo, Huadong; Annoni, Alessandro; Bian, Ling; de Bie, Kees; Campbell, Frederick; Craglia, Max; Ehlers, Manfred; van Genderen, John; Jackson, Davina; Lewis, Anthony J; Pesaresi, Martino; Remetey-Fülöpp, Gábor; Simpson, Richard; Skidmore, Andrew; Wang, Changlin; Woodgate, Peter

2012-07-10

A speech of then-Vice President Al Gore in 1998 created a vision for a Digital Earth, and played a role in stimulating the development of a first generation of virtual globes, typified by Google Earth, that achieved many but not all the elements of this vision. The technical achievements of Google Earth, and the functionality of this first generation of virtual globes, are reviewed against the Gore vision. Meanwhile, developments in technology continue, the era of "big data" has arrived, the general public is more and more engaged with technology through citizen science and crowd-sourcing, and advances have been made in our scientific understanding of the Earth system. However, although Google Earth stimulated progress in communicating the results of science, there continue to be substantial barriers in the public's access to science. All these factors prompt a reexamination of the initial vision of Digital Earth, and a discussion of the major elements that should be part of a next generation.

EarthN: A new Earth System Nitrogen Model

OpenAIRE

Johnson, Benjamin W.; Goldblatt, Colin

2018-01-01

The amount of nitrogen in the atmosphere, oceans, crust, and mantle have important ramifications for Earth's biologic and geologic history. Despite this importance, the history and cycling of nitrogen in the Earth system is poorly constrained over time. For example, various models and proxies contrastingly support atmospheric mass stasis, net outgassing, or net ingassing over time. In addition, the amount available to and processing of nitrogen by organisms is intricately linked with and prov...

Earth's variable rotation

Science.gov (United States)

Hide, Raymond; Dickey, Jean O.

1991-01-01

Recent improvements in geodetic data and practical meteorology have advanced research on fluctuations in the earth's rotation. The interpretation of these fluctuations is inextricably linked with studies of the dynamics of the earth-moon system and dynamical processes in the liquid metallic core of the earth (where the geomagnetic field originates), other parts of the earth's interior, and the hydrosphere and atmosphere. Fluctuations in the length of the day occurring on decadal time scales have implications for the topographay of the core-mantle boundary and the electrical, magnetic, ande other properties of the core and lower mantle. Investigations of more rapid fluctuations bear on meteorological studies of interannual, seasonal, and intraseasonal variations in the general circulation of the atmosphere and the response of the oceans to such variations.

Melting in super-earths.

Science.gov (United States)

Stixrude, Lars

2014-04-28

We examine the possible extent of melting in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and core formation, the timescale of cooling and its dependence on viscosity and partial melting, thermal regulation via the temperature dependence of viscosity, and the melting curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and core formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate melting. We estimate melting curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the core-mantle boundary and at the surface to the local silicate melting temperature. We find that ancient (∼4 Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses.

Project Earth Science

CERN Document Server

Holt, Geoff

2011-01-01

Project Earth Science: Astronomy, Revised 2nd Edition, involves students in activities that focus on Earth's position in our solar system. How do we measure astronomical distances? How can we look back in time as we gaze across vast distances in space? How would our planet be different without its particular atmosphere and distance to our star? What are the geometries among Earth, the Moon, and the Sun that yield lunar phases and seasons? Students explore these concepts and others in 11 teacher-tested activities.

Studies with the EC-Earth seamless Earth system prediction model

NARCIS (Netherlands)

Hazeleger, W.; Bintanja, R.

2012-01-01

EC-Earth is a new Earth System Model (ESM) based on the operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts (ECMWF). Climate and weather forecasting applications share a common ancestry and are build on the same physical principles. The emerging concept of

Earth Science Informatics - Overview

Science.gov (United States)

Ramapriyan, H. K.

2017-01-01

Over the last 10-15 years, significant advances have been made in information management, there are an increasing number of individuals entering the field of information management as it applies to Geoscience and Remote Sensing data, and the field of informatics has come to its own. Informatics is the science and technology of applying computers and computational methods to the systematic analysis, management, interchange, and representation of science data, information, and knowledge. Informatics also includes the use of computers and computational methods to support decision making and applications. Earth Science Informatics (ESI, a.k.a. geoinformatics) is the application of informatics in the Earth science domain. ESI is a rapidly developing discipline integrating computer science, information science, and Earth science. Major national and international research and infrastructure projects in ESI have been carried out or are on-going. Notable among these are: the Global Earth Observation System of Systems (GEOSS), the European Commissions INSPIRE, the U.S. NSDI and Geospatial One-Stop, the NASA EOSDIS, and the NSF DataONE, EarthCube and Cyberinfrastructure for Geoinformatics. More than 18 departments and agencies in the U.S. federal government have been active in Earth science informatics. All major space agencies in the world, have been involved in ESI research and application activities. In the United States, the Federation of Earth Science Information Partners (ESIP), whose membership includes over 180 organizations (government, academic and commercial) dedicated to managing, delivering and applying Earth science data, has been working on many ESI topics since 1998. The Committee on Earth Observation Satellites (CEOS)s Working Group on Information Systems and Services (WGISS) has been actively coordinating the ESI activities among the space agencies.The talk will present an overview of current efforts in ESI, the role members of IEEE GRSS play, and discuss

The International Year of Planet Earth (2007-2009):Earth Sciences for Society

Institute of Scientific and Technical Information of China (English)

Eduardo F.J.de Mulder; Ted Nield; Edward Derbyshire

2006-01-01

Natural disasters like the 2004 tsunami bear graphic testimony to the Earth's incredible power. More effective use of geoscientific knowledge can save lives and protect property. Such knowledge also enables us to satisfy, in a sustainable manner,the growing need for Earth's resources by an expanding human population. Such knowledge is readily available in the practical experience and publications of some half a million Earth scientists all over the world, a professional community that is ready and willing to contribute to a safer, healthier and wealthier society if called upon by politicians and decision makers. Professional guidance by Earth scientists is available in many aspects of everyday life including, for example, identification of the best areas for urban expansion, sites to avoid for waste disposal, the location of new underground fresh water resources, and where certain toxic agents implicated in Earth-related diseases may be located, etc.The International Year of Planet Earth (2007-2009) aims to build on existing knowledge and make it more available for the improvement of everyday life, especially in the less developed countries, as expressed in the Year's subtitle: Earth sciences for Society. Ambitious outreach and science programmes constitute the backbone of the International Year, now politically endorsed by all 191 member states of the United Nations Organisation which has proclaimed 2008, the central year of the triennium, as the UN Year of Planet Earth. This paper describes who is behind the initiative,how it will work, and how the political process leading to United Nations proclamation proceeded. It also describes the financial and organisational aspects of the International Year, sets out the commitments necessary for the realization of the Year's ambitions by all nations, and explains how the raising of US$ 20 million will be approached.

OpenEarth : Using Google Earth as outreach for NCK's data

NARCIS (Netherlands)

de Boer, G.J.; Baart, F.; Bruens, A.; Damsma, T.; van Geer, P.; Grasmeijer, B.; den Heijer, C.; van Koningsveld, M.; Santinelli, G.

2012-01-01

In 2003 various projects at Deltares and the TU-Delft merged their toolboxes for marine and coastal science and engineering into one toolbox, culminating in 2008 in an open source release, known as OpenEarthTools (OET). OpenEarth adopts the wikipedia approach to growth: web 2.0 crowd sourcing. All

Rare earths: occurrence, production and applications

International Nuclear Information System (INIS)

Murthy, T.K.S.; Mukherjee, T.K.

2002-01-01

The mining and processing of rare earth minerals, particularly of monazite, began in a modest way in 1880s for commercialized production of mantle for gas lighting. For all major applications up to mid-twentieth century- production of lighter flints, misch metal as a metallurgical alloying agent, colouring, decolourizing and polishing agents for glass, petroleum cracking catalysts and arc-carbons, unseparated or partially separated rare earths were adequate. These applications continue till today. With the development and industrial application of powerful techniques like ion exchange and solvent extraction for the separation of rare earths, the decades after 1960 saw increasing utilization of the specific properties of the individual rare earths. Some of these advanced technological applications include: special glass for optical systems including camera lenses, phosphors for colour television, cathode ray tubes and fluorescent lighting, X-ray intensification screens, high intensity permanent magnets, electro optical devices, lasers, hydrogen storage materials, hydride rechargeable batteries, photomagnetic data storage systems, autoexhaust catalysts, special ceramics of unusual toughness, artificial diamonds and nonpoisonous plastic colorants. The topics covered in the book include rare earths: their story identity, rare earth resources, processing of ores and recovery of mixed rare earths products, separation and purification of rare earths, nonmetallic applications of rare earths, rare earth metals: production and applications, rare earth alloys and their applications, analysis of rare earth, processing of rare earth resources in India by Indian Rare Earth Ltd. and availability and market conditions

The earth's gravitational field

Digital Repository Service at National Institute of Oceanography (India)

Ramprasad, T.

. But to say that gravity acts downwards is not correct. Gravity acts down, no matter where you stand on the Earth. It is better to say that on Earth gravity pulls objects towards the centre of the Earth. So no matter where you are on Earth all objects fall... pull than objects at the poles. In combination, the equatorial bulge and the effects of centrifugal force mean that sea-level gravitational acceleration increases from about 9.780 m/s² at the equator to about 9.832 m/s² at the poles, so an object...

Rare earths 1998 market update

International Nuclear Information System (INIS)

Tourre, J.M.

1998-01-01

The rare earth industry has always been a world of rapid change with the emergence of new markets, new ores and new players, as well as the disappearance of old applications. Rare earth based products are used in a great diversity of applications such as hard disk drives, CD drives, batteries, capacitors, pigments, ceramics, polishing powders, fuel cells, flints, catalyst converter, fluid cracking catalysts, etc. South East Asia holds the largest share of the known reserve of rare earth ores and is one of the major markets for rare earth compounds; in the last ten years, China has become the largest producer of rare earth intermediates as well as an important exporter of separated rare earth elements. Today, China has approximately 150 factories producing rare earth compounds, most of which are experiencing financial difficulties due to the lack of knowledge of true market needs, lack of control of their distribution channels and production over-capacity. Recently the Chinese rare earth producers have recognized the situation and efforts are underway to rationalize rare earth production. Japan has dominated many of the major application markets, and is by far the largest market for metal and alloy products. This will remain the case for the next five years; however, new countries are emerging as significant users of rare earth products such as Korea, Taiwan and Malaysia. During the last ten years rare earth producers adjusted to several radical changes that affected the raw materials, the application mix and the price structure. New producers have emerged, especially from China; some have subsequently stopped their activities while others have focused their efforts in a specific market segment

Sun-Earth Scientists and Native Americans Collaborate on Sun-Earth Day

Science.gov (United States)

Ng, C. Y.; Lopez, R. E.; Hawkins, I.

2004-12-01

Sun-Earth Connection scientists have established partnerships with several minority professional societies to reach out to the blacks, Hispanics and Native American students. Working with NSBP, SACNAS, AISES and NSHP, SEC scientists were able to speak in their board meetings and national conferences, to network with minority scientists, and to engage them in Sun-Earth Day. Through these opportunities and programs, scientists have introduced NASA research results as well indigenous views of science. They also serve as role models in various communities. Since the theme for Sun-Earth Day 2005 is Ancient Observatories: Timeless Knowledge, scientists and education specialists are hopeful to excite many with diverse backgrounds. Sun-Earth Day is a highly visible annual program since 2001 that touches millions of students and the general public. Interviews, classroom activities and other education resources are available on the web at sunearthday.nasa.gov.

Earth and Universe

Energy Technology Data Exchange (ETDEWEB)

Kosygin, Yu A

1986-12-01

Rocks, the age of which according to certain data exceeds considerably the recognized age of the Earth and approximates the age of the Universe, have been detected on the Earth. There is a necessity to coordinate the geological data with cosmological structures.

Baltic Earth - Earth System Science for the Baltic Sea Region

Science.gov (United States)

Meier, Markus; Rutgersson, Anna; Lehmann, Andreas; Reckermann, Marcus

2014-05-01

The Baltic Sea region, defined as its river catchment basin, spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It encompasses most of the Scandinavian Peninsula in the west; most of Finland and parts of Russia, Belarus, and the Baltic states in the east; and Poland and small parts of Germany and Denmark in the south. The region represents an old cultural landscape, and the Baltic Sea itself is among the most studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. Preliminary grand challenges and topics for which Working Groups have been installed include: • Salinity dynamics in the Baltic Sea • Land-Sea biogeochemical feedbacks in the Baltic Sea region • Natural hazards and extreme events in the Baltic Sea region • Understanding sea level dynamics in the Baltic Sea • Understanding regional variability of water and energy exchange • Utility of Regional Climate Models • Assessment of Scenario Simulations

Near Earth Objects

DEFF Research Database (Denmark)

Wolff, Stefan

2006-01-01

, Near Earth Objects: Asteroids and comets following paths that bring them near the Earth. NEOs have collided with the Earth since its formation, some causing local devastation, some causing global climate changes, yet the threat from a collision with a near Earth object has only recently been recognised...... and accepted. The European Space Agency mission Gaia is a proposed space observatory, designed to perform a highly accurate census of our galaxy, the Milky Way, and beyond. Through accurate measurement of star positions, Gaia is expected to discover thousands of extra-solar planets and follow the bending...... of starlight by the Sun, and therefore directly observe the structure of space-time. This thesis explores several aspects of the observation of NEOs with Gaia, emphasising detection of NEOs and the quality of orbits computed from Gaia observations. The main contribution is the work on motion detection...

Earth's electric field

International Nuclear Information System (INIS)

Kelley, M.C.

1978-01-01

The earth becomes charged during thunderstorm activity and discharges through the weak conducting atmosphere. Balloon and rocket studies infer that a high altitude electric field penetrates virtually unattenuated through the atmosphere, at least as far as balloon heights. The field has two primary sources. At low and mid latitudes, interaction between the earth's magnetic field and the neutral wind creates electric fields. At latitudes above 60 0 , the high altitude electrical structure is dominated by the interaction between the solar wind and the earth's magnetic field. The auroral light is emitted by atmospheric atoms and molecules excited by electrons with potentials of many thousands volts. The potentials are induced by the solar wind. Recent satellite data shows that the electrons get this energy by passing through a localized electric field about 6000 km above the auroral zone. Several rocket and satellite experiments used to study the earth's electric field are discussed

The Chinese Society of Rare Earth is Studying The Feasibility of Marketing Rare Earth Futures

Institute of Scientific and Technical Information of China (English)

2015-01-01

Lin Donglu,secretary-general of the Chinese Society of Rare Earth recently said,the Chinese Society of Rare Earth undertook the research on subject of the National Social Science Fund Foundation on the reform of Chinese rare earth trading pricing mechanism on promoting RMB globalization,and is focusing on studying the feasibility of marketing rare earth futures variety.

Rare earth germanates

International Nuclear Information System (INIS)

Bondar', I.A.; Vinogradova, N.V.; Dem'yanets, L.N.

1983-01-01

From the viewpoint of structural chemistry and general regularities controlling formation reactions of compounds and phases in melts, solid and gaseous states, recent achievements in the chemistry of rare earth germanates are generalized. Methods of synthesizing germanates, systems on the base of germanium oxides and rare earths are considered. The data on crystallochemical characteristics are tabulated. Individual compounds of scandium germanate are also characterized. Processes of germanate formation using the data of IR-spectroscopy, X-ray phase analysis are studied. The structure and morphotropic series of rare earth germanates and silicates are determined. Fields of their present and possible future application are considered

Rotation of a Moonless Earth

Science.gov (United States)

Lissauer, Jack J.; Barnes, Jason W.; Chambers, John E.

2013-01-01

We numerically explore the obliquity (axial tilt) variations of a hypothetical moonless Earth. Previous work has shown that the Earth's Moon stabilizes Earth's obliquity such that it remains within a narrow range, between 22.1 deg and 24.5 deg. Without lunar influence, a frequency-map analysis by Laskar et al. showed that the obliquity could vary between 0 deg. and 85 deg. This has left an impression in the astrobiology community that a large moon is necessary to maintain a habitable climate on an Earth-like planet. Using a modified version of the orbital integrator mercury, we calculate the obliquity evolution for moonless Earths with various initial conditions for up to 4 Gyr. We find that while obliquity varies significantly more than that of the actual Earth over 100,000 year timescales, the obliquity remains within a constrained range, typically 20-25 deg. in extent, for timescales of hundreds of millions of years. None of our Solar System integrations in which planetary orbits behave in a typical manner show obliquity accessing more than 65% of the full range allowed by frequency-map analysis. The obliquities of moonless Earths that rotate in the retrograde direction are more stable than those of pro-grade rotators. The total obliquity range explored for moonless Earths with rotation periods shorter than 12 h is much less than that for slower-rotating moonless Earths. A large moon thus does not seem to be needed to stabilize the obliquity of an Earth-like planet on timescales relevant to the development of advanced life.

Effect of irradiation times on the polymerization depth of contemporary fissure sealants with different opacities

Directory of Open Access Journals (Sweden)

Boniek Castillo Dutra Borges

2011-04-01

Full Text Available The aim of this study was to evaluate the depth of curing of 10 contemporary blue light-activated dental flowable materials at several opacities, influenced by different irradiation times using FT-IR spectroscopy. Fifty-five specimens (n = 5 with a 5-mm diameter and 1-mm thickness of translucent (Opallis Flow T, yellowed (Master Flow A2; Opallis Flow A2; Natural Flow A2; Fluroshield Yellowed, and opaque materials (Master Flow OA2; Natural Flow O; Opallis Flow OA3.5; Opallis Flow OP; Fluroshield White were obtained at six curing times (10s, 20s, 30s, 40s, 50s, and 60s using a high-intensity LED (Coltolux, Coltène/Whaledent. The degree of conversion (DC (% was obtained using the Nexus 470 FTIR Spectrometer (Nicolet Instruments, USA. The FTIR-ATR spectra for uncured and cured samples were analyzed using a ZnSe crystal. The top and bottom surfaces of the cured specimens were analyzed to obtain the depth of curing. Two-way ANOVA was used to analyze the data. The highest curing depth was obtained by Natural Flow OA2, while the lowest was shown by Master Flow OA2. The shortest curing time generated similar depths of cure in comparison with the most extensive for Opallis Flow A2 and Fluroshield Yellowed. Therefore, depth of curing, influenced by the irradiation time, was dependent on the materials. Using the Natural Flow OA2 opaque sealant and the 10-s curing time for Opallis Flow A2 and Fluroshield Yellowed may represent alternative approaches to sealing tooth fissures.

Geomagnetic field of earth

International Nuclear Information System (INIS)

Delipetrev, Marjan; Delipetrev, Blagoj; Panovska, Sanja

2008-01-01

In this paper is introduced the theory of geomagnetic field of the Earth. A homogenous and isotropic sphere is taken for a model of Earth with a bar magnet at its center as a magnetic potential. The understanding of the real origin of geomagnetic field produced from differential rotation of inner core with respect to the outer core of Earth is here presented. Special attention is given to the latest observed data of the established net of geomagnetic repeat stations in the Republic of Macedonia. Finally, the maps of elements of geomagnetic field and the equation for calculation of normal magnetic field of Earth are provided. (Author)

Magnetic field of the Earth

Science.gov (United States)

Popov, Aleksey

2013-04-01

The magnetic field of the Earth has global meaning for a life on the Earth. The world geophysical science explains: - occurrence of a magnetic field of the Earth it is transformation of kinetic energy of movements of the fused iron in the liquid core of Earth - into the magnetic energy; - the warming up of a kernel of the Earth occurs due to radioactive disintegration of elements, with excretion of thermal energy. The world science does not define the reasons: - drift of a magnetic dipole on 0,2 a year to the West; - drift of lithospheric slabs and continents. The author offers: an alternative variant existing in a world science the theories "Geodynamo" - it is the theory « the Magnetic field of the Earth », created on the basis of physical laws. Education of a magnetic field of the Earth occurs at moving the electric charge located in a liquid kernel, at rotation of the Earth. At calculation of a magnetic field is used law the Bio Savara for a ring electric current: dB = . Magnetic induction in a kernel of the Earth: B = 2,58 Gs. According to the law of electromagnetic induction the Faradey, rotation of a iron kernel of the Earth in magnetic field causes occurrence of an electric field Emf which moves electrons from the center of a kernel towards the mantle. So of arise the radial electric currents. The magnetic field amplifies the iron of mantle and a kernel of the Earth. As a result of action of a radial electric field the electrons will flow from the center of a kernel in a layer of an electric charge. The central part of a kernel represents the field with a positive electric charge, which creates inverse magnetic field Binv and Emfinv When ?mfinv = ?mf ; ?inv = B, there will be an inversion a magnetic field of the Earth. It is a fact: drift of a magnetic dipole of the Earth in the western direction approximately 0,2 longitude, into a year. Radial electric currents a actions with the basic magnetic field of a Earth - it turn a kernel. It coincides with laws

Safety aspects in rare earths recovery

International Nuclear Information System (INIS)

Bhattacharya, R.

2014-01-01

Recovery of rare earths involves mining of beach sands, mineral separation to obtain monazite and its chemical processing to obtain rare earth composites. The composites are then subjected to further chemical treatment to obtain individual rare earths. Although the separated out rare earths are not radioactive, the process for recovery of rare earths involve both radiological as well as conventional hazards. This paper highlights the safety aspects in the mining, mineral separation and chemical processing of monazite to obtain rare earths

Our Mission to Planet Earth: A guide to teaching Earth system science

Science.gov (United States)

1994-01-01

Volcanic eruptions, hurricanes, floods, and El Nino are naturally occurring events over which humans have no control. But can human activities cause additional environmental change? Can scientists predict the global impacts of increased levels of pollutants in the atmosphere? Will the planet warm because increased levels of greenhouse gases, produced by the burning of fossil fuels, trap heat and prevent it from being radiated back into space? Will the polar ice cap melt, causing massive coastal flooding? Have humans initiated wholesale climatic change? These are difficult questions, with grave implications. Predicting global change and understanding the relationships among earth's components have increased in priority for the nation. The National Aeronautics and Space Administration (NASA), along with many other government agencies, has initiated long-term studies of earth's atmosphere, oceans, and land masses using observations from satellite, balloon, and aircraft-borne instruments. NASA calls its research program Mission to Planet Earth. Because NASA can place scientific instruments far above earth's surface, the program allows scientists to explore earth's components and their interactions on a global scale.

Moving Closer to EarthScope: A Major New Initiative for the Earth Sciences*

Science.gov (United States)

Simpson, D.; Blewitt, G.; Ekstrom, G.; Henyey, T.; Hickman, S.; Prescott, W.; Zoback, M.

2002-12-01

EarthScope is a scientific research and infrastructure initiative designed to provide a suite of new observational facilities to address fundamental questions about the evolution of continents and the processes responsible for earthquakes and volcanic eruptions. The integrated observing systems that will comprise EarthScope capitalize on recent developments in sensor technology and communications to provide Earth scientists with synoptic and high-resolution data derived from a variety of geophysical sensors. An array of 400 broadband seismometers will spend more than ten years crossing the contiguous 48 states and Alaska to image features that make up the internal structure of the continent and underlying mantle. Additional seismic and electromagnetic instrumentation will be available for high resolution imaging of geological targets of special interest. A network of continuously recording Global Positioning System (GPS) receivers and sensitive borehole strainmeters will be installed along the western U.S. plate boundary. These sensors will measure how western North America is deforming, what motions occur along faults, how earthquakes start, and how magma flows beneath active volcanoes. A four-kilometer deep observatory bored directly into the San Andreas fault will provide the first opportunity to observe directly the conditions under which earthquakes occur, to collect fault rocks and fluids for laboratory study, and to monitor continuously an active fault zone at depth. All data from the EarthScope facilities will be openly available in real-time to maximize participation from the scientific community and to provide on-going educational outreach to students and the public. EarthScope's sensors will revolutionize observational Earth science in terms of the quantity, quality and spatial extent of the data they provide. Turning these data into exciting scientific discovery will require new modes of experimentation and interdisciplinary cooperation from the Earth

Earth science big data at users' fingertips: the EarthServer Science Gateway Mobile

Science.gov (United States)

Barbera, Roberto; Bruno, Riccardo; Calanducci, Antonio; Fargetta, Marco; Pappalardo, Marco; Rundo, Francesco

2014-05-01

The EarthServer project (www.earthserver.eu), funded by the European Commission under its Seventh Framework Program, aims at establishing open access and ad-hoc analytics on extreme-size Earth Science data, based on and extending leading-edge Array Database technology. The core idea is to use database query languages as client/server interface to achieve barrier-free "mix & match" access to multi-source, any-size, multi-dimensional space-time data -- in short: "Big Earth Data Analytics" - based on the open standards of the Open Geospatial Consortium Web Coverage Processing Service (OGC WCPS) and the W3C XQuery. EarthServer combines both, thereby achieving a tight data/metadata integration. Further, the rasdaman Array Database System (www.rasdaman.com) is extended with further space-time coverage data types. On server side, highly effective optimizations - such as parallel and distributed query processing - ensure scalability to Exabyte volumes. In this contribution we will report on the EarthServer Science Gateway Mobile, an app for both iOS and Android-based devices that allows users to seamlessly access some of the EarthServer applications using SAML-based federated authentication and fine-grained authorisation mechanisms.

Seismological evidence for a localized mushy zone at the Earth?s inner core boundary

OpenAIRE

Tian, Dongdong; Wen, Lianxing

2017-01-01

Although existence of a mushy zone in the Earth?s inner core has been hypothesized several decades ago, no seismic evidence has ever been reported. Based on waveform modeling of seismic compressional waves that are reflected off the Earth?s inner core boundary, here we present seismic evidence for a localized 4?8?km thick zone across the inner core boundary beneath southwest Okhotsk Sea with seismic properties intermediate between those of the inner and outer core and of a mushy zone. Such a ...

The Earth Information Exchange: A Portal for Earth Science From the ESIP Federation

Science.gov (United States)

Wertz, R.; Hutchinson, C.; Hardin, D.

2006-12-01

The Federation of Earth Science Information Partners is a unique consortium of more than 90 organizations that collect, interpret and develop applications for remotely sensed Earth Observation Information. Included in the ESIP network are NASA, NOAA and USGS data centers, research universities, government research laboratories, supercomputer facilities, education resource providers, information technology innovators, nonprofit organizations and commercial enterprises. The consortium's work is dedicated to providing the most up-to-date, science-based information to researchers and decision-makers who are working to understand and address the environmental, economic and social challenges facing our planet. By increasing the use and usability of Earth observation data and linking it with decision-making tools, the Federation partners leverage the value of these important data resources for the betterment of society and our planet. To further the dissemination of Earth Science data, the Federation is developing the Earth Information Exchange (EIE). The EIE is a portal that will provide access to the vast information holdings of the members' organizations in one web-based location and will provides a robust marketplace in which the products and services needed to use and understand this information can be readily acquired. Since the Federation membership includes the federal government's Earth observing data centers, we believe that the impact of the EIE on Earth science research and education and environmental policy making will be profound. In the EIE, Earth observation data, products and services, are organized by the societal benefits categories defined by the international working group developing the Global Earth Observation System of Systems (GEOSS). The quality of the information is ensured in each of the Exchange's issue areas by maintaining working groups of issue area researchers and practitioners who serve as stewards for their respective communities. The

Rare earths and actinides

International Nuclear Information System (INIS)

Coqblin, B.

1982-01-01

This paper reviews the different properties of rare-earths and actinides, either as pure metals or as in alloys or compounds. Three different cases are considered: (i) First, in the case of 'normal' rare-earths which are characterized by a valence of 3, we discuss essentially the magnetic ordering, the coexistence between superconductivity and magnetism and the properties of amorphous rare-earth systems. (ii) Second, in the case of 'anomalous' rare-earths, we distinguish between either 'intermediate-valence' systems or 'Kondo' systems. Special emphasis is given to the problems of the 'Kondo lattice' (for compounds such as CeAl 2 ,CeAl 3 or CeB 6 ) or the 'Anderson lattice' (for compounds such as TmSe). The problem of neutron diffraction in these systems is also discussed. (iii) Third, in the case of actinides, we can separate between the d-f hybridized and almost magnetic metals at the beginning of the series and the rare-earth like the metals after americium. (orig.)

Flooding Effect on Earth Walls

Directory of Open Access Journals (Sweden)

Meysam Banimahd

2010-12-01

Full Text Available Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.

Earth before life.

Science.gov (United States)

Marzban, Caren; Viswanathan, Raju; Yurtsever, Ulvi

2014-01-09

A recent study argued, based on data on functional genome size of major phyla, that there is evidence life may have originated significantly prior to the formation of the Earth. Here a more refined regression analysis is performed in which 1) measurement error is systematically taken into account, and 2) interval estimates (e.g., confidence or prediction intervals) are produced. It is shown that such models for which the interval estimate for the time origin of the genome includes the age of the Earth are consistent with observed data. The appearance of life after the formation of the Earth is consistent with the data set under examination.

Development of an earth pressure model for design of earth retaining structures in piedmont soil.

Science.gov (United States)

2008-10-01

Anecdotal evidence suggests that earth pressure in Piedmont residual soils is typically over estimated. Such estimates of earth pressure impact the design of earth retaining structures used on highway projects. Thus, the development of an appropriate...

Earth as art three

Science.gov (United States)

,

2010-01-01

For most of us, deserts, mountains, river valleys, coastlines even dry lakebeds are relatively familiar features of the Earth's terrestrial environment. For earth scientists, they are the focus of considerable scientific research. Viewed from a unique and unconventional perspective, Earth's geographic attributes can also be a surprising source of awe-inspiring art. That unique perspective is space. The artists for the Earth as Art Three exhibit are the Landsat 5 and Landsat 7 satellites, which orbit approximately 705 kilometers (438 miles) above the Earth's surface. While studying the images these satellites beam down daily, researchers are often struck by the sheer beauty of the scenes. Such images inspire the imagination and go beyond scientific value to remind us how stunning, intricate, and simply amazing our planet's features can be. Instead of paint, the medium for these works of art is light. But Landsat satellite sensors don't see light as human eyes do; instead, they see radiant energy reflected from Earth's surface in certain wavelengths, or bands, of red, green, blue, and infrared light. When these different bands are combined into a single image, remarkable patterns, colors, and shapes emerge. The Earth as Art Three exhibit provides fresh and inspiring glimpses of different parts of our planet's complex surface. The images in this collection were chosen solely based on their aesthetic appeal. Many of the images have been manipulated to enhance color variations or details. They are not intended for scientific interpretation only for your viewing pleasure. Enjoy!

PREFACE: The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014)

Science.gov (United States)

Lumban Gaol, Ford; Soewito, Benfano

2015-01-01

The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014), was held at Discovery Kartika Plaza Hotel, Kuta, Bali, Indonesia during 11 - 12 October 2014. The AeroEarth 2014 conference aims to bring together researchers and engineers from around the world. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 98 papers and after rigorous review, 17 papers were accepted. The participants come from eight countries. There are four Parallel Sessions and two invited Speakers. It is an honour to present this volume of IOP Conference Series: Earth and Environmental Science (EES) and we deeply thank the authors for their enthusiastic and high-grade contributions. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee

COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)

Science.gov (United States)

Oleson, Steven R.; McGuire, Melissa L.

2009-01-01

In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.

NASA Earth Exchange (NEX)

Data.gov (United States)

National Aeronautics and Space Administration — The NASA Earth Exchange (NEX) represents a new platform for the Earth science community that provides a mechanism for scientific collaboration and knowledge sharing....

Earth Science Enterprise Technology Strategy

Science.gov (United States)

1999-01-01

NASA's Earth Science Enterprise (ESE) is dedicated to understanding the total Earth system and the effects of natural and human-induced changes on the global environment. The goals of ESE are: (1) Expand scientific knowledge of the Earth system using NASA's unique vantage points of space, aircraft, and in situ platforms; (2) Disseminate information about the Earth system; and (3) Enable the productive use of ESE science and technology in the public and private sectors. ESE has embraced the NASA Administrator's better, faster, cheaper paradigm for Earth observing missions. We are committed to launch the next generation of Earth Observing System (EOS) missions at a substantially lower cost than the EOS first series. Strategic investment in advanced instrument, spacecraft, and information system technologies is essential to accomplishing ESE's research goals in the coming decades. Advanced technology will play a major role in shaping the ESE fundamental and applied research program of the future. ESE has established an Earth science technology development program with the following objectives: (1) To accomplish ESE space-based and land-based program elements effectively and efficiently; and (2) To enable ESE's fundamental and applied research programs goals as stated in the NASA Strategic Plan.

Using EarthLabs to Enhance Earth Science Curriculum in Texas

Science.gov (United States)

Chegwidden, D. M.; Ellins, K. K.; Haddad, N.; Ledley, T. S.

2012-12-01

As an educator in Texas, a state that values and supports an Earth Science curriculum, I find it essential to educate my students who are our future voting citizens and tax payers. It is important to equip them with tools to understand and solve the challenges of solving of climate change. As informed citizens, students can help to educate others in the community with basic knowledge of weather and climate. They can also help to dispose of the many misconceptions that surround the climate change, which is perceived as a controversial topic. As a participant in a NSF-sponsored Texas Earth and Space (TXESS) Revolution teacher professional development program, I was selected to participate in a curriculum development project led by TERC to develop and test education resources for the EarthLabs climate literacy collection. I am involved in the multiple phases of the project, including reviewing labs that comprise the Climate, Weather and Biosphere module during the development phase, pilot teaching the module with my students, participating in research, and delivering professional development to other Texas teachers to expose them to the content found in the module and to encourage them to incorporate it into their teaching. The Climate, Weather and the Biosphere module emphasizes different forms of evidence and requires that learners apply different inquiry-based approaches to build the knowledge they need to develop as climate literate citizens. My involvement with the EarthLabs project has strengthened my overall knowledge and confidence to teach about Earth's climate system and climate change. In addition, the project has produced vigorous classroom discussion among my students as well as encouraged me to collaborate with other educators through our delivery of professional development to other teachers. In my poster, I will share my experiences, describe the impact the curriculum has made on my students, and report on challenges and valuable lessons gained by

Evidence for triple-junction rifting focussed on local magmatic centres along Parga Chasma, Venus

Science.gov (United States)

Graff, J. R.; Ernst, R. E.; Samson, C.

2018-05-01

Parga Chasma is a discontinuous rift system marking the southern boundary of the Beta-Atla-Themis (BAT) region on Venus. Along a 1500 km section of Parga Chasma, detailed mapping of Magellan Synthetic Aperture Radar images has revealed 5 coronae, 11 local rift zones distinct from a regional extension pattern, and 47 graben-fissure systems with radiating (28), linear (12) and circumferential (7) geometries. The magmatic centres of these graben-fissure systems typically coincide with coronae or large volcanoes, although a few lack any central magmatic or tectonic feature (i.e. are cryptic). Some of the magmatic centres are interpreted as the foci of triple-junction rifting that form the 11 local rift zones. Cross-cutting relationships between graben-fissure systems and local rift faults reveal synchronous formation, implying a genetic association. Additionally, cross-cutting relationships show that local rifting events postdate the regional extension along Parga Chasma, further indicating multiple stages of rifting. Evidence for multiple centres of younger magmatism and local rifting against a background of regional extension provides an explanation for the discontinuous morphology of Parga Chasma. Examination of the Atlantic Rift System (prior to ocean opening) on Earth provides an analogue to the rift morphologies observed on Venus.

The Earth is a Planet Too!

Science.gov (United States)

Cairns, Brian

2014-01-01

When the solar system formed, the sun was 30 dimmer than today and Venus had an ocean. As the sun brightened, a runaway greenhouse effect caused the Venus ocean to boil away. At times when Earth was younger, the sun less bright, and atmospheric CO2 less, Earth froze over (snowball Earth). Earth is in the sweet spot today. Venus is closer to sun than Earth is, but cloud-covered Venus absorbs only 25 of incident sunlight, while Earth absorbs 70. Venus is warmer because it has a thick carbon dioxide atmosphere causing a greenhouse effect of several hundred degrees. Earth is Goldilocks choice among the planets, the one that is just right for life to exist. Not too hot. Not too cold. How does the Earth manage to stay in this habitable range? Is there a Gaia phenomenon keeping the climate in bounds? A nice idea, but it doesnt work. Today, greenhouse gas levels are unprecedented compared to the last 450,000 years.

Modeling the earth system

Energy Technology Data Exchange (ETDEWEB)

Ojima, D. [ed.

1992-12-31

The 1990 Global Change Institute (GCI) on Earth System Modeling is the third of a series organized by the Office for Interdisciplinary Earth Studies to look in depth at particular issues critical to developing a better understanding of the earth system. The 1990 GCI on Earth System Modeling was organized around three themes: defining critical gaps in the knowledge of the earth system, developing simplified working models, and validating comprehensive system models. This book is divided into three sections that reflect these themes. Each section begins with a set of background papers offering a brief tutorial on the subject, followed by working group reports developed during the institute. These reports summarize the joint ideas and recommendations of the participants and bring to bear the interdisciplinary perspective that imbued the institute. Since the conclusion of the 1990 Global Change Institute, research programs, nationally and internationally, have moved forward to implement a number of the recommendations made at the institute, and many of the participants have maintained collegial interactions to develop research projects addressing the needs identified during the two weeks in Snowmass.

The earth's hydrological cycle

CERN Document Server

Bonnet, R-M; Calisto, M; Destouni, G; Gurney, R; Johannessen, J; Kerr, Y; Lahoz, WA; Rast, M

2014-01-01

This book gives a comprehensive presentation of our present understanding of the Earth's Hydrological cycle and the problems, consequences and impacts that go with this topic. Water is a central component in the Earth's system. It is indispensable for life on Earth in its present form and influences virtually every aspect of our planet's life support system. On relatively short time scales, atmospheric water vapor interacts with the atmospheric circulation and is crucial in forming the Earth's climate zones. Water vapor is the most powerful of the greenhouse gases and serves to enhance the tropospheric temperature. The dominant part of available water on Earth resides in the oceans. Parts are locked up in the land ice on Greenland and Antarctica and a smaller part is estimated to exist as groundwater. If all the ice over the land and all the glaciers were to melt, the sea level would rise by some 80 m. In comparison, the total amount of water vapor in the atmosphere is small; it amounts to ~ 25 kg/m2, or the ...

The Earth System Model

Science.gov (United States)

Schoeberl, Mark; Rood, Richard B.; Hildebrand, Peter; Raymond, Carol

2003-01-01

The Earth System Model is the natural evolution of current climate models and will be the ultimate embodiment of our geophysical understanding of the planet. These models are constructed from components - atmosphere, ocean, ice, land, chemistry, solid earth, etc. models and merged together through a coupling program which is responsible for the exchange of data from the components. Climate models and future earth system models will have standardized modules, and these standards are now being developed by the ESMF project funded by NASA. The Earth System Model will have a variety of uses beyond climate prediction. The model can be used to build climate data records making it the core of an assimilation system, and it can be used in OSSE experiments to evaluate. The computing and storage requirements for the ESM appear to be daunting. However, the Japanese ES theoretical computing capability is already within 20% of the minimum requirements needed for some 2010 climate model applications. Thus it seems very possible that a focused effort to build an Earth System Model will achieve succcss.

A high-orbit collimating infrared earth simulator

International Nuclear Information System (INIS)

Zhang Guoyu; Jiang Huilin; Fang Yang; Yu Huadong; Xu Xiping; Wang, Lingyun; Liu Xuli; Huang Lan; Yue Shixin; Peng Hui

2007-01-01

The earth simulator is the most important testing equipment ground-based for the infrared earth sensor, and it is also a key component in the satellite controlling system. for three orbit heights 18000Km, 35786Km and 42000Km, in this paper we adopt a project of collimation and replaceable earth diaphragm and develop a high orbit collimation earth simulator. This simulator can afford three angles 15.19 0 , 17.46 0 and 30.42 0 , resulting simulating the earth on the ground which can be seen in out space by the satellite. In this paper we introduce the components, integer structure, and the earth's field angles testing method of the earth simulator in detail. Germanium collimation lens is the most important component in the earth simulator. According to the optical configuration parameter of Germanium collimation lens, we find the location and size of the earth diaphragm and the hot earth by theoretical analyses and optics calculation, which offer foundation of design in the study of the earth simulator. The earth angle is the index to scale the precision of earth simulator. We test the three angles by experiment and the results indicate that three angles errors are all less than ±0.05 0

Raman scattering of rare earth hexaborides

International Nuclear Information System (INIS)

Ogita, Norio; Hasegawa, Takumi; Udagawa, Masayuki; Iga, Fumitoshi; Kunii, Satoru

2009-01-01

Raman scattering spectra were measured for the rare-earth hexaborides RB 6 (R = Ce, Gd, or Dy). All Raman-active phonons due to B 6 vibrations were observed in the range 600 - 1400 cm -1 . Anomalous peaks were detected below 200 cm -1 , which correspond to vibrations of rare-earth ion excited by second-order Raman scattering process. The intensity and energy of the rare-earth mode decrease with decreasing temperature. This suggests that the rare-earth ion vibrates in a shallow and anharmonic potential due to the boron cage. Using the reported values of mean square displacement of rare-earth ion, we estimated the anharmonic contribution for the rare-earth vibrations.

The Earth's Plasmasphere

Science.gov (United States)

Gallagher, D. L.

2015-01-01

The Earth's plasmasphere is an inner part of the magneteosphere. It is located just outside the upper ionosphere located in Earth's atmosphere. It is a region of dense, cold plasma that surrounds the Earth. Although plasma is found throughout the magnetosphere, the plasmasphere usually contains the coldest plasma. Here's how it works: The upper reaches of our planet's atmosphere are exposed to ultraviolet light from the Sun, and they are ionized with electrons that are freed from neutral atmospheric particles. The results are electrically charged negative and positive particles. The negative particles are electrons, and the positive particles are now called ions (formerly atoms and molecules). If the density of these particles is low enough, this electrically charged gas behaves differently than it would if it were neutral. Now this gas is called plasma. The atmospheric gas density becomes low enough to support the conditions for a plasma around earth at about 90 kilometers above Earth's surface. The electrons in plasma gain more energy, and they are very low in mass. They move along Earth's magnetic field lines and their increased energy is enough to escape Earth's gravity. Because electrons are very light, they don't have to gain too much kinetic energy from the Sun's ultraviolet light before gravity loses its grip on them. Gravity is not all that holds them back, however. As more and more electrons begin to escape outward, they leave behind a growing net positive electric charge in the ionosphere and create a growing net negative electric charge above the ionosphere; an electric field begins to develop (the Pannekoek-Rosseland E-field). Thus, these different interacting charges result in a positively charged ionosphere and negatively charged region of space above it. Very quickly this resulting electric field opposed upward movement of the electrons out of the ionosphere. The electrons still have this increased energy, however, so the electric field doesn't just

Earth formation porosity log

International Nuclear Information System (INIS)

Smith, H.D.; Smith, M.P.; Schultz, W.E.

1977-01-01

A method for determining the porosity of earth formations in the vicinity of a cased well borehole is described, comprising the steps of: irradiating the earth formations in the vicinity of the cased well borehole with fast neutrons from a source of fast neutrons passed into the borehole; and generating a signal representative of the fast neutron population present in the well borehole at a location in the borehole, the signal is functionally related to the porosity of the earth formations in the vicinity of the borehole

Origin of the earth and moon

International Nuclear Information System (INIS)

Ringwood, A.E.

1981-01-01

The composition of the Earth's interior and its bearing on the Earth's origin are discussed. It seems likely that the terrestrial planets formed by the accretion of solid planetisimals from the nebula of dust and gas left behind during the formation of the Sun. The scenario proposed is simpler than others. New evidence based upon a comparison of siderophile element abundances in the Earth's mantle and in the Moon imply that the Moon was derived from the Earth's mantle after the Earth's core had segregated

Factors Affecting Student Success with a Google Earth-Based Earth Science Curriculum

Science.gov (United States)

Blank, Lisa M.; Almquist, Heather; Estrada, Jen; Crews, Jeff

2016-01-01

This study investigated to what extent the implementation of a Google Earth (GE)-based earth science curriculum increased students' understanding of volcanoes, earthquakes, plate tectonics, scientific reasoning abilities, and science identity. Nine science classrooms participated in the study. In eight of the classrooms, pre- and post-assessments…

STS-39 Earth observation of Earth's limb at sunset shows atmospheric layers

Science.gov (United States)

1991-01-01

STS-39 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, shows the Earth's limb at sunset with numerous atmospheric scattering layers highlighted. The layers consist of fine particles suspended in very stable layers of the atmosphere. The layers act as a prism for the sunlight.

Unique Non-Keplerian Orbit Vantage Locations for Sun-Earth Connection and Earth Science Vision Roadmaps

Science.gov (United States)

Folta, David; Young, Corissa; Ross, Adam

2001-01-01

The purpose of this investigation is to determine the feasibility of attaining and maintaining unique non-Keplerian orbit vantage locations in the Earth/Moon environment in order to obtain continuous scientific measurements. The principal difficulty associated with obtaining continuous measurements is the temporal nature of astrodynamics, i.e., classical orbits. This investigation demonstrates advanced trajectory designs to meet demanding science requirements which cannot be met following traditional orbital mechanic logic. Examples of continuous observer missions addressed include Earth pole-sitters and unique vertical libration orbits that address Sun-Earth Connection and Earth Science Vision roadmaps.

Earth and planetary sciences

International Nuclear Information System (INIS)

Wetherill, G.W.; Drake, C.L.

1980-01-01

The earth is a dynamic body. The major surface manifestation of this dynamism has been fragmentation of the earth's outer shell and subsequent relative movement of the pieces on a large scale. Evidence for continental movement came from studies of geomagnetism. As the sea floor spreads and new crust is formed, it is magnetized with the polarity of the field at the time of its formation. The plate tectonics model explains the history, nature, and topography of the oceanic crust. When a lithospheric plate surmounted by continental crust collides with an oceanic lithosphere, it is the denser oceanic lithosphere that is subducted. Hence the ancient oceans have vanished and the knowledge of ancient earth will require deciphering the complex continental geological record. Geochemical investigation shows that the source region of continental rocks is not simply the depleted mantle that is characteristic of the source region of basalts produced at the oceanic ridges. The driving force of plate tectonics is convection within the earth, but much remains to be learned about the convection and interior of the earth. A brief discussion of planetary exploration is given

The radioactive earth

International Nuclear Information System (INIS)

Plant, J.A.; Saunders, A.D.

1996-01-01

Uranium, thorium and potassium are the main elements contributing to natural terrestrial radioactivity. The isotopes 238 U, 235 U, 232 Th and 40 K decay with half-lives so long that significant amounts remain in the earth, providing a continuing source of heat. The slow decay of these isotopes also provides the basis for radiometric age dating and isotopic modelling of the evolution of the earth and its crust. There is a complex interplay between their heat production and the processes involved in crust formation. Phenomena such as volcanism, earthquakes, and large-scale hydrothermal activity associated with ore deposition reflect the dissipation of heat energy from the earth, much of which is derived from natural radioactivity. The higher levels of radioactive elements during the early history of the earth resulted in higher heat flow. All three of the radioactive elements are strongly partitioned into the continental crust, but within the crust their distribution is determined by their different chemical properties. The behaviour of U, which has two commonly occurring oxidation states, is more complex than that of Th and K. Uranium deposits are diverse, and are mostly associated with granites, acid volcanics, or detrital sedimentary rocks. The most important U deposits economically are unconformity-type ores of Proterozoic age, in which U is enriched by up to 5 x 10 6 with respect to bulk earth values. In some cases natural radioactivity can be of environmental concern. The most significant risk is posed by accumulations of radon, the gaseous daughter product of U. (author)

Geohistory. Global evolution of the earth

Energy Technology Data Exchange (ETDEWEB)

Ozima, Minoru

1987-01-01

A full understanding of the earth's evolution can be achieved only by considering it as a continuous process starting with the birth of the solar system. This book traces the evolution of the earth, mainly on the basis of radiogenic isotopes from long half-life parent elements, and discusses it in terms of the latest developments in astrophysical theory, which impose unique constraints on the earth's origin and early evolution. By its 'historical' nature, geohistorical study also offers a unique approach to forecasting the future of the earth, yielding useful clues for the understanding of environmental problems, such as radioactive waste disposal. This book aims to provide an outline of global evolution of the planet earth for students of general science and for earth scientists.

What can earth tide measurements tell us about ocean tides or earth structure?

Science.gov (United States)

Baker, T. F.

1978-01-01

Current experimental problems in Earth tides are reviewed using comparisons of tidal gravity and tilt measurements in Europe with loading calculations are examples. The limitations of present day instrumentation and installation techniques are shown as well as some of the ways in which they can be improved. Many of the geophysical and oceanographic investigations that are possible with Earth tide measurements are discussed with emphasis on the percentage accuracies required in the measurements in order to obtain new information about Earth or its oceans.

EARTH FROM SPACE

Indian Academy of Sciences (India)

Table of contents. EARTH FROM SPACE · Slide 2 · Earth System · Slide 4 · Global water cycle · Slide 6 · Slide 7 · Direct Observations of Recent Climate Change · Slide 9 · Slide 10 · Snow cover and Arctic sea ice are decreasing · Polar Melting & Global Heat Transport · Antarctica: Melting and Thickening · Slide 14 · Slide 15.

Visualizing Earth Materials

Science.gov (United States)

Cashman, K. V.; Rust, A.; Stibbon, E.; Harris, R.

2016-12-01

Earth materials are fundamental to art. They are pigments, they are clay, they provide form and color. Earth scientists, however, rarely attempt to make the physical properties of Earth materials visible through art, and similarly many artists use Earth materials without fully understanding their physical and chemical properties. Here we explore the intersection between art and science through study of the physical properties of Earth materials as characterized in the laboratory, and as transferred to paper using different techniques and suspending media. One focus of this collaboration is volcanic ash. Ash is interesting scientifically because its form provides information on the fundamental processes that drive volcanic eruptions, and determines its transport properties, and thus its potential to affect populations far downwind of the volcano. Ash properties also affect its behavior as an art material. From an aesthetic point of view, ash lends a granular surface to the image; it is also uncontrollable, and thus requires engagement between artist and medium. More fundamentally, using ash in art creates an exchange between the medium and the subject matter, and imparts something of the physical, visceral experience of volcanic landscapes to the viewer. Another component of this work uses powdered rock as a printing medium for geologic maps. Because different types of rock create powders with different properties (grain size distributions and shapes), the geology is communicated not only as color, but also by the physical characteristics of the material as it interacts with the paper. More importantly, the use of actual rocks samples as printing material for geologic maps not only makes a direct connection between the map and the material it represents, but also provides an emotional connection between the map, the viewer and the landscape, its colors, textures and geological juxtapositions. Both case studies provide examples not only of ways in which artists can

Earth's Trojan asteroid.

Science.gov (United States)

Connors, Martin; Wiegert, Paul; Veillet, Christian

2011-07-27

It was realized in 1772 that small bodies can stably share the same orbit as a planet if they remain near 'triangular points' 60° ahead of or behind it in the orbit. Such 'Trojan asteroids' have been found co-orbiting with Jupiter, Mars and Neptune. They have not hitherto been found associated with Earth, where the viewing geometry poses difficulties for their detection, although other kinds of co-orbital asteroid (horseshoe orbiters and quasi-satellites) have been observed. Here we report an archival search of infrared data for possible Earth Trojans, producing the candidate 2010 TK(7). We subsequently made optical observations which established that 2010 TK(7) is a Trojan companion of Earth, librating around the leading Lagrange triangular point, L(4). Its orbit is stable over at least ten thousand years.

Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites

Science.gov (United States)

Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus

2017-04-01

The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.

HABEBEE: habitability of eyeball-exo-Earths.

Science.gov (United States)

Angerhausen, Daniel; Sapers, Haley; Citron, Robert; Bergantini, Alexandre; Lutz, Stefanie; Queiroz, Luciano Lopes; da Rosa Alexandre, Marcelo; Araujo, Ana Carolina Vieira

2013-03-01

Extrasolar Earth and super-Earth planets orbiting within the habitable zone of M dwarf host stars may play a significant role in the discovery of habitable environments beyond Earth. Spectroscopic characterization of these exoplanets with respect to habitability requires the determination of habitability parameters with respect to remote sensing. The habitable zone of dwarf stars is located in close proximity to the host star, such that exoplanets orbiting within this zone will likely be tidally locked. On terrestrial planets with an icy shell, this may produce a liquid water ocean at the substellar point, one particular "Eyeball Earth" state. In this research proposal, HABEBEE: exploring the HABitability of Eyeball-Exo-Earths, we define the parameters necessary to achieve a stable icy Eyeball Earth capable of supporting life. Astronomical and geochemical research will define parameters needed to simulate potentially habitable environments on an icy Eyeball Earth planet. Biological requirements will be based on detailed studies of microbial communities within Earth analog environments. Using the interdisciplinary results of both the physical and biological teams, we will set up a simulation chamber to expose a cold- and UV-tolerant microbial community to the theoretically derived Eyeball Earth climate states, simulating the composition, atmosphere, physical parameters, and stellar irradiation. Combining the results of both studies will enable us to derive observable parameters as well as target decision guidance and feasibility analysis for upcoming astronomical platforms.

Pull vs. Push: How OmniEarth Delivers Better Earth Observation Information to Subscribers

Science.gov (United States)

Fish, C.; Slagowski, S.; Dyrud, L.; Fentzke, J.; Hargis, B.; Steerman, M.

2015-04-01

Until very recently, the commercialization of Earth observation systems has largely occurred in two ways: either through the detuning of government satellites or the repurposing of NASA (or other science) data for commercial use. However, the convergence of cloud computing and low-cost satellites is enabling Earth observation companies to tailor observation data to specific markets. Now, underserved constituencies, such as agriculture and energy, can tap into Earth observation data that is provided at a cadence, resolution and cost that can have a real impact to their bottom line. To connect with these markets, OmniEarth fuses data from a variety of sources, synthesizes it into useful and valuable business information, and delivers it to customers via web or mobile interfaces. The "secret sauce" is no longer about having the highest resolution imagery, but rather it is about using that imagery - in conjunction with a number of other sources - to solve complex problems that require timely and contextual information about our dynamic and changing planet. OmniEarth improves subscribers' ability to visualize the world around them by enhancing their ability to see, analyze, and react to change in real time through a solutions-as-a-service platform.

Connecting Earth Systems: Developing Holistic Understanding through the Earth-System-Science Model

Science.gov (United States)

Gagnon, Valoree; Bradway, Heather

2012-01-01

For many years, Earth science concepts have been taught as thematic units with lessons in nice, neat chapter packages complete with labs and notes. But compartmentalized Earth science no longer exists, and implementing teaching methods that support student development of holistic understandings can be a time-consuming and difficult task. While…

Metallothermic reduction of rare earth oxides

International Nuclear Information System (INIS)

Sharma, R.A.

1986-01-01

Rare earth oxides can be reduced to rare earth metals by a novel, high yield, metallothermic process. The oxides are dispersed in a suitable, molten, calcium chloride bath along with sodium metal. The sodium reacts with the calcium chloride to produce calcium metal which reduces the rare earth oxides to rare earth metals. The metals are collected in a discrete layer in the reaction vessel

Earthing the human body influences physiologic processes.

Science.gov (United States)

Sokal, Karol; Sokal, Pawel

2011-04-01

This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

Rare earth industries: Strategies for Malaysia

International Nuclear Information System (INIS)

2011-01-01

Evidently, many reports cite Malaysia as having reasonably substantial amounts of rare earths elements. In fact, based on the rare earths found in the residual tin deposits alone, Malaysia has about 30,000 tonnes. This does not take into account unmapped deposits which experts believe may offer more tonnages of rare earths. Brazil which is reported to have about 48,000 tonnes has announced plans to invest aggressively in the rare earths business. China has on record the largest reserves with about 36 million tonnes. This explains why China has invested heavily in the entire value chain of the rare earths business. Chinas committed investment in rare earths started many years ago when the country's foremost leaders proclaimed the strategic position of rare earths in the world economy. That forecast is now a reality where the rise in the green high-tech economy is seen driving global demand for rare earths in a big way. Malaysia needs to discover and venture into new economic growth areas. This will help fuel the country's drive to achieve a high income status by 2020 as articulated in the New Economic Model (NEM) and the many supporting Economic Transformation Plans that the Government has recently launched. Rare earths may be the new growth area for Malaysia. However, the business opportunities should not just be confined to the mining, extraction and production of rare earths elements alone if Malaysia is to maximise benefits from this industry. The industry's gold mine is in the downstream products. This is also the sector that China wants to expand. Japan which now controls about 50 % of the global market for downstream rare earths-based high-tech components is desperately looking for partners to grow their stake in the business. Malaysia needs to embark on the right strategies in order to build the rare earths industry in the country. What are the strategies? (author)

The Australian Computational Earth Systems Simulator

Science.gov (United States)

Mora, P.; Muhlhaus, H.; Lister, G.; Dyskin, A.; Place, D.; Appelbe, B.; Nimmervoll, N.; Abramson, D.

2001-12-01

Numerical simulation of the physics and dynamics of the entire earth system offers an outstanding opportunity for advancing earth system science and technology but represents a major challenge due to the range of scales and physical processes involved, as well as the magnitude of the software engineering effort required. However, new simulation and computer technologies are bringing this objective within reach. Under a special competitive national funding scheme to establish new Major National Research Facilities (MNRF), the Australian government together with a consortium of Universities and research institutions have funded construction of the Australian Computational Earth Systems Simulator (ACcESS). The Simulator or computational virtual earth will provide the research infrastructure to the Australian earth systems science community required for simulations of dynamical earth processes at scales ranging from microscopic to global. It will consist of thematic supercomputer infrastructure and an earth systems simulation software system. The Simulator models and software will be constructed over a five year period by a multi-disciplinary team of computational scientists, mathematicians, earth scientists, civil engineers and software engineers. The construction team will integrate numerical simulation models (3D discrete elements/lattice solid model, particle-in-cell large deformation finite-element method, stress reconstruction models, multi-scale continuum models etc) with geophysical, geological and tectonic models, through advanced software engineering and visualization technologies. When fully constructed, the Simulator aims to provide the software and hardware infrastructure needed to model solid earth phenomena including global scale dynamics and mineralisation processes, crustal scale processes including plate tectonics, mountain building, interacting fault system dynamics, and micro-scale processes that control the geological, physical and dynamic

Who Uses Earth Observations? User Types in Group on Earth Observations

Science.gov (United States)

Fontaine, K. S.

2011-12-01

How can we communicate concepts in the physical sciences unless we know our audience? The Group on Earth Observations (GEO) User Interface Committee (UIC) has a responsibility within GEO to support and advocate for the user community in the development of Global Earth Observations System of Systems (GEOSS) and related work. As part of its efforts, the UIC has been working on developing a taxonomy that can be used to characterize the broad spectrum of users of GEOSS and its data, services, and applications. The user type taxonomy is designed to be broad and flexible but aims at describing the needs of the users GEOSS is going to serve. These user types represent a continuum of users of Earth observations from research through to decision support activities, and it includes organizations that use GEOSS as a tool to provide data and services for customers and consumers of the information. The classification scheme includes factors about skills and capacity for using Earth observations, sophistication level, spatial resolution, latency, and frequency of data. As part of the effort to develop a set of User Types, the GEO UIC foresees that those inside and outside GEO can use the typologies to understand how to engage users at a more effective level. This talk presents the GEOSS User Type taxonomy, explaining the development and highlights of key feedback. The talk will highlight possible ways to use the User Type taxonomy to communicate concepts and promote the use of Earth observations to a wide variety of users.

Rare earth industries: Downstream business

International Nuclear Information System (INIS)

2011-01-01

The value chain of the rare earths business involves mining, extraction, processing, refining and the manufacture of an extensive range of downstream products which find wide applications in such industries including aerospace, consumer electronics, medical, military, automotive, renewable wind and solar energy and telecommunications. In fact the entire gamut of the high-tech industries depends on a sustainable supply of rare earths elements. The explosive demand in mobile phones is an excellent illustration of the massive potential that the rare earths business offers. In a matter of less than 20 years, the number of cell phones worldwide has reached a staggering 5 billion. Soon, going by the report of their growth in sales, the world demand for cell phones may even exceed the global population. Admittedly, the rare earths business does pose certain risks. Top among the risks are the health and safety risks. The mining, extraction and refining of rare earths produce residues and wastes which carry health and safety risks. The residues from the extraction and refining are radioactive, while their effluent waste streams do pose pollution risks to the receiving rivers and waterways. But, as clearly elaborated in a recent report by IAEA experts, there are technologies and systems available to efficiently mitigate such risks. The risks are Rare Earth manageable. However, it is crucial that the risk and waste management procedures are strictly followed and adhered to. This is where effective monitoring and surveillance throughout the life of all such rare earths facilities is crucial. Fortunately, Malaysia's regulatory standards on rare earths follow international standards. In some areas, Malaysia's regulatory regime is even more stringent than the international guidelines. (author)

Learning More About Our Earth: An Exploration of NASA's Contributions to Earth Science Through Remote Sensing Technologies

Science.gov (United States)

Lindsay, Francis

2017-01-01

NASA is commonly known for its pioneering work in space exploration and the technological advancements that made access to space possible. NASA is now increasingly known for the agency's research and technologies that support the Earth sciences. This is a presentation focusing on NASA's Earth science efforts told mostly through the technological innovations NASA uses to achieve a greater understanding of the Earth, making it possible to explore the Earth as a system. Enabling this science is NASA's fleet of over two dozen Earth science spacecraft, supported by aircraft, ships and ground observations. NASA's Earth Observing System (EOS) is a coordinated series of polar-orbiting and low inclination satellites for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans. With the launching of the three flagship satellite missions, Terra, Aqua and Aura, beginning in 1999, NASA's initial Mission to Planet Earth made it possible to measure aspects of the environment that touch the lives of every person around the world. NASA harnessing the unique space-based platform means, fortunately, no planet is better studied than the one we actually live on.

Greenhouse Earth: A Traveling Exhibition

International Nuclear Information System (INIS)

Booth, W.H.; Caesar, S.

1992-09-01

The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a ''demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a ''satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change

The earth and the moon

CERN Document Server

Elkins-Tanton, Linda T

2010-01-01

The moon is the only body in the solar system outside of the Earth that has been visited by humans. More than 440 pounds of lunar material are brought by NASA and Soviet space missions to Earth for study. The information gleaned about the moon from this relatively small pile of rocks is mind-boggling and stands as the greatest proof that Martian planetary science would be greatly enhanced by returning samples to Earth. Compositional studies of lunar rocks show that the moon and the Earth are made of similar material, and because lunar material has not been reworked through erosion and plate te

Rare earth-iron-boron premanent magnets

International Nuclear Information System (INIS)

Ghendehari, M.H.

1988-01-01

This patent describes a method for producing rare earth-iron-boron permanent magnets containing added rare earth oxide, comprising the steps of: (a) mixing a particulate alloy containing at least one rare earth metal, iron, and boron with at least one particulate rare earth oxide; (b) aligning magnetic domains of the mixture in a magnetic field; (c) compacting the aligned mixture to form a shape; and (d) sintering the compacted shape

The industry of metallic rare earths (R.E.)

International Nuclear Information System (INIS)

Poirier, P.

1979-01-01

The following subjects are discussed: rare earths resources (rare earths abondance and world reserves, main ores). Rare earths separation and purification (ionic exchange, solvent extraction). Metallic rare earths and their mixtures, metallothermic reduction of oxides or fluorides (Ca, Mg, Al, Si or rare earth metals), Co-reduction process for intermetallic compounds (SmCo 5 ). Industrial applications of metallic rare earths (traditional applications such as flints, nodular cast iron, steel refining, magnesium industrie, applications under development such as rare earths/cobalt magnets, LaNi 5 for hydrogen storage, special alloys (automotive post combustion), magnetostrictive alloys). Economical problems: rare earth are elements relatively abundant and often at easily accessible prices. However, this group of 15 elements are liable to certain economical restraints. It is difficult to crack ore for only one rare earth. Availability of one given rare earth must be associated with the other corresponding rare earths to absorb all the other rare earths in other applications. Rare-earth industry has a strong expanding rate. 20% per year average for 6 years with Rhone-Poulenc. Thanks to their exceptional, specific characteristics rare earths have a bright future particularly for their metals

Rigidly framed earth retaining structures thermal soil structure interaction of buildings supporting unbalanced lateral earth pressures

CERN Document Server

Aboumoussa, Walid

2014-01-01

Structures placed on hillsides often present a number of challenges and a limited number of economical choices for site design. An option sometimes employed is to use the building frame as a retaining element, comprising a Rigidly Framed Earth Retaining Structure (RFERS). The relationship between temperature and earth pressure acting on RFERS, is explored in this monograph through a 4.5 year monitoring program of a heavily instrumented in service structure. The data indicated that the coefficient of earth pressure behind the monitored RFERS had a strong linear correlation with temperature. The study also revealed that thermal cycles, rather than lateral earth pressure, were the cause of failure in many structural elements. The book demonstrates that depending on the relative stiffness of the retained soil mass and that of the structural frame, the developed lateral earth pressure, during thermal expansion, can reach magnitudes several times larger than those determined using classical earth pressure theories....

Sally Ride EarthKAM - Automated Image Geo-Referencing Using Google Earth Web Plug-In

Science.gov (United States)

Andres, Paul M.; Lazar, Dennis K.; Thames, Robert Q.

2013-01-01

Sally Ride EarthKAM is an educational program funded by NASA that aims to provide the public the ability to picture Earth from the perspective of the International Space Station (ISS). A computer-controlled camera is mounted on the ISS in a nadir-pointing window; however, timing limitations in the system cause inaccurate positional metadata. Manually correcting images within an orbit allows the positional metadata to be improved using mathematical regressions. The manual correction process is time-consuming and thus, unfeasible for a large number of images. The standard Google Earth program allows for the importing of KML (keyhole markup language) files that previously were created. These KML file-based overlays could then be manually manipulated as image overlays, saved, and then uploaded to the project server where they are parsed and the metadata in the database is updated. The new interface eliminates the need to save, download, open, re-save, and upload the KML files. Everything is processed on the Web, and all manipulations go directly into the database. Administrators also have the control to discard any single correction that was made and validate a correction. This program streamlines a process that previously required several critical steps and was probably too complex for the average user to complete successfully. The new process is theoretically simple enough for members of the public to make use of and contribute to the success of the Sally Ride EarthKAM project. Using the Google Earth Web plug-in, EarthKAM images, and associated metadata, this software allows users to interactively manipulate an EarthKAM image overlay, and update and improve the associated metadata. The Web interface uses the Google Earth JavaScript API along with PHP-PostgreSQL to present the user the same interface capabilities without leaving the Web. The simpler graphical user interface will allow the public to participate directly and meaningfully with EarthKAM. The use of

Cosmic rays and Earth's climate

DEFF Research Database (Denmark)

Svensmark, Henrik

2000-01-01

During the last solar cycle the Earth's cloud cover underwent a modulation in phase with the cosmic ray flux. Assuming that there is a causal relationship between the two, it is expected and found that the Earth's temperature follows more closely decade variations in cosmic ray flux than other...... solar activity parameters. If the relationship is real the state of the Heliosphere affects the Earth's climate....

Sun-Earth Day, 2001

Science.gov (United States)

Adams, Mitzi L.; Mortfield, P.; Hathaway, D. H.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

To promote awareness of the Sun-Earth connection, NASA's Marshall Space Flight Center, in collaboration with the Stanford SOLAR Center, sponsored a one-day Sun-Earth Day event on April 27, 2001. Although "celebrated" on only one day, teachers and students from across the nation, prepared for over a month in advance. Workshops were held in March to train teachers. Students performed experiments, results of which were shared through video clips and an internet web cast. Our poster includes highlights from student experiments (grades 2 - 12), lessons learned from the teacher workshops and the event itself, and plans for Sun-Earth Day 2002.

Earthing the Human Body Influences Physiologic Processes

Science.gov (United States)

Sokal, Karol

2011-01-01

Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

The Earth's Biosphere

Science.gov (United States)

2002-01-01

In the last five years, scientists have been able to monitor our changing planet in ways never before possible. The Sea-viewing Wide Field-of-View Sensor (SeaWiFS), aboard the OrbView-2 satellite, has given researchers an unprecedented view of the biological engine that drives life on Earth-the countless forms of plants that cover the land and fill the oceans. 'There is no question the Earth is changing. SeaWiFS has enabled us, for the first time, to monitor the biological consequences of that change-to see how the things we do, as well as natural variability, affect the Earth's ability to support life,' said Gene Carl Feldman, SeaWiFS project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. SeaWiFS data, based on continuous daily global observations, have helped scientists make a more accurate assessment of the oceans' role in the global carbon cycle. The data provide a key parameter in a number of ecological and environmental studies as well as global climate-change modeling. The images of the Earth's changing land, ocean and atmosphere from SeaWiFS have documented many previously unrecognized phenomena. The image above shows the global biosphere from June 2002 measured by SeaWiFS. Data in the oceans is chlorophyll concentration, a measure of the amount of phytoplankton (microscopic plants) living in the ocean. On land SeaWiFS measures Normalized Difference Vegetation Index, an indication of the density of plant growth. For more information and images, read: SeaWiFS Sensor Marks Five Years Documenting Earth'S Dynamic Biosphere Image courtesy SeaWiFS project and copyright Orbimage.

Chemical analysis of rare earth elements

International Nuclear Information System (INIS)

Tsukahara, Ryoichi; Sakoh, Takefumi; Nagai, Iwao

1994-01-01

Recently attention has been paid to ICP-AES or ICP-MS, and the reports on the analysis of rare earth elements by utilizing these methods continue to increase. These reports have become to take about 30% of the reports on rare earth analysis, and this is because these methods are highly sensitive to rare earth elements, and also these methods have spread widely. In ICP-AES and ICP-MS, mostly solution samples are measured, therefore, solids must be made into solution. At the time of quantitatively determining the rare earth elements of low concentration, separation and concentration are necessary. Referring to the literatures reported partially in 1990 and from 1991 to 1993, the progress of ICP-AES and ICP-MS is reported. Rare earth oxides and the alloys containing rare earth elements are easily decomposed with acids, but the decomposition of rocks is difficult, and its method is discussed. The separation of the rare earth elements from others in geochemical samples, cation exchange process is frequently utilized. Also solvent extraction process has been studied. For the separation of rare earth elements mutually, chromatography is used. The spectral interference in spectral analysis was studied. The comparison of these methods with other methods is reported. (K.I)

Ancient and Medieval Earth in Armenia

Science.gov (United States)

Farmanyan, S. V.

2015-07-01

Humankind has always sought to recognize the nature of various sky related phenomena and tried to give them explanations. The purpose of this study is to identify ancient Armenians' pantheistic and cosmological perceptions, world view, notions and beliefs related to the Earth. The paper focuses on the structure of the Earth and many other phenomena of nature that have always been on a major influence on ancient Armenians thinking. In this paper we have compared the term Earth in 31 languages. By discussing and comparing Universe structure in various regional traditions, myths, folk songs and phraseological units we very often came across to "Seven Heavens" (Seven heavens is a part of religious cosmology found in many major religions such as Islam, Judaism, Hinduism and Christianity (namely Catholicism) and "Seven Earths". Armenians in their turn divided Earth and Heavens into seven layers. And in science too, both the Earth and the Heavens have 7 layers. The Seven Heavens refer to the layers of our atmosphere. The Seven Earths refer to the layers of the Earth (from core to crust), as well as seven continents. We conclude that the perception of celestial objects varies from culture to culture and preastronomy had a significant impact on humankind, particularly on cultural diversities.

Radiation environment of the earth

International Nuclear Information System (INIS)

Furukawa, Masahide

2003-01-01

The radiation environment of the earth consists of natural and artificial radiation. This paper explains the distribution and some exposure examples of natural radiation and the relation between life and natural radiation. The earth was born before about 46 hundreds of millions of years. In the present earth, there are some natural radiations with long half-life originated by the earth. They are 232 Th (141 hundreds of millions of years of half-life), 238 U (45 hundreds of millions of years of half-life) and 40 K (13 hundreds of millions of years of half-life). Natural radiation (α-, β-, and γ-ray) from natural radionuclides exists everywhere in the earth. Natural radio nuclides are heat source of the earth, which is about 0.035 μcal/g/y. γ-ray from them is called as ''the earth's crust γ-ray'', which is about 55 nGy/h average of the world and about 50 nGy/h in Japan. The distribution of γ-ray is depended on the kinds of soil and rock. 222 Rn and 230 Rn are rare gases and the concentration of them in a room is larger than outside. Natural radiations originated from the cosmos are proton, ionizing components, neutron component with muon and electron, 3 H, 14 C and 10 Be. Effect of cosmic rays on birth of life, change of temperature, amount of cloud and ultra resistant cell are stated. (S.Y.)

Magnetic Storms at Mars and Earth

DEFF Research Database (Denmark)

Vennerstrøm, Susanne; Falkenberg, Thea Vilstrup

In analogy with magnetic storms at the Earth, periods of significantly enhanced global magnetic activity also exist at Mars. The extensive database of magnetic measurements from Mars Global Surveyor (MGS), covering almost an entire solar cycle, is used in combination with geomagnetic activity...... indices at Earth to compare the occurrence of magnetic storms at Mars and Earth. Based on superposed epochs analysis the time-development of typical magnetic storms at Mars and Earth is described. In contradiction to storms at Earth, most magnetic storms at Mars are found to be associated...... with heliospheric current sheet crossings, where the IMF changes polarity. While most storms at the Earth occur due to significant southward excursions of the IMF associated with CMEs, at Mars most storms seem to be associated with the density enhancement of the heliospheric current sheet. Density enhancements...

Earth as art 4

Science.gov (United States)

,

2016-03-29

Landsat 8 is the latest addition to the long-running series of Earth-observing satellites in the Landsat program that began in 1972. The images featured in this fourth installment of the Earth As Art collection were all acquired by Landsat 8. They show our planet’s diverse landscapes with remarkable clarity.Landsat satellites see the Earth as no human can. Not only do they acquire images from the vantage point of space, but their sensors record infrared as well as visible wavelengths of light. The resulting images often reveal “hidden” details of the Earth’s land surface, making them invaluable for scientific research.As with previous Earth As Art exhibits, these Landsat images were selected solely for their aesthetic appeal. Many of the images have been manipulated to enhance color variations or details. They are not intended for scientific interpretation—only for your viewing pleasure. What do you see in these unique glimpses of the Earth’s continents, islands, and coastlines?

Etude fondamentale de l'imbibition dans un réservoir fissuré Basic Research on Inbibition in a Fractured Reservoir

Directory of Open Access Journals (Sweden)

Iffly R.

2006-11-01

Full Text Available L'efficacité du balayage d'un gisement fissuré par de l'eau d'injection dépend étroitement de l'importance et de la vitesse d'imbibition de l'eau par les blocs matriciels. De nombreuses expériences de laboratoire, réalisées sur des échantillons de roche et avec les fluides provenant d'un gisement exploité par Elf, ont permis de préciser l'influence, sur la récupération de l'huile, de la hauteur et de la perméabilité des blocs, ainsi que des conditions régnant à leurs limites (certaines fissures peuvent contenir, soit de l'eau, soit de l'huile, soit encore être étanches. Les résultats mettent en évidence le rôle essentiel des liaisons physico-chimiques entre l'eau de gisement, l'eau injectée, l'huile et la roche, à tout moment de l'imbibition. De légers écarts dans la composition lithologique de la roche peuvent modifier considérablement les lois de récupération. Par ailleurs, la présence dans les fluides de certaines molécules organiques peut influencer la récupération de l'huile beaucoup plus que ce que l'on pourrait attendre a priori des seules variations du terme a cos 6,. Comme ces liaisons physico-chimiques sont encore mal connues, donc non modélisables, il n'est en général pas légitime de procéder à des expériences d'imbibition avec des fluides et/ou des échantillons de roche ne provenant pas du gisement étudié. Dans ces conditions, les résultats de cette étude sont nécessairement spécifiques du champ considéré. Toutefois, les méthodes utilisées, l'analyse des résultats qui est faite, ainsi que l'influence des principaux paramètres sur ces résultats, présentent un degré de généralité évident. Les mesures de laboratoire, complétées par des simulations numériques, ont conduit à un ensemble cohérent de résultats permettant de comprendre le rôle respectif de la gravité, de la capillarité, des conditions aux limites et des effets d'extrémité, entre autres. Waterflood

Dimension of the Earth's general ellipsoid

Czech Academy of Sciences Publication Activity Database

Burša, Milan; Kenyon, S.; Kouba, J.; Raděj, K.; Šíma, Zdislav; Vatrt, V.; Vojtíšková, M.

2002-01-01

Roč. 91, č. 1 (2002), s. 31-41 ISSN 0167-9295 Institutional research plan: CEZ:AV0Z1003909 Keywords : Earth's dimensions * Earth's ellipsoid * fundamental constants Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 1.364, year: 2002

The international earth observing system: a cultural debate about earth sciences from space

NARCIS (Netherlands)

Menenti, M.

1996-01-01

This paper gives an overview of the International Earth Observing System, i.e. the combined earth observation programmes of space agencies worldwide and of the relevance of advanced space-borne sensor systems to the study and understanding of interactions between land surface and atmosphere. The

Rare earth elements: end use and recyclability

Science.gov (United States)

Goonan, Thomas G.

2011-01-01

Rare earth elements are used in mature markets (such as catalysts, glassmaking, lighting, and metallurgy), which account for 59 percent of the total worldwide consumption of rare earth elements, and in newer, high-growth markets (such as battery alloys, ceramics, and permanent magnets), which account for 41 percent of the total worldwide consumption of rare earth elements. In mature market segments, lanthanum and cerium constitute about 80 percent of rare earth elements used, and in new market segments, dysprosium, neodymium, and praseodymium account for about 85 percent of rare earth elements used. Regardless of the end use, rare earth elements are not recycled in large quantities, but could be if recycling became mandated or very high prices of rare earth elements made recycling feasible.

NASA's Earth Science Data Systems

Science.gov (United States)

Ramapriyan, H. K.

2015-01-01

NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

Detecting Water on Super-Earths Using JAVST

Science.gov (United States)

Deming, D.

2010-01-01

Nearby lower train sequence stars host a class of planets known as Super-Earths, that have no analog in our own solar system. Super-Earths are rocky and/or icy planets with masses up to about 10 Earth masses, They are expected to host atmospheres generated by a number of processes including accretion of chondritic material. Water vapor should be a common constituent of super-Earth atmospheres, and may be detectable in transiting super-Earths using transmission spectroscopy during primar y eclipse, and emission spectroscopy at secondary eclipse. I will discuss the prospects for super-Earth atmospheric measurements using JWST.

How Big is Earth?

Science.gov (United States)

Thurber, Bonnie B.

2015-08-01

How Big is Earth celebrates the Year of Light. Using only the sunlight striking the Earth and a wooden dowel, students meet each other and then measure the circumference of the earth. Eratosthenes did it over 2,000 years ago. In Cosmos, Carl Sagan shared the process by which Eratosthenes measured the angle of the shadow cast at local noon when sunlight strikes a stick positioned perpendicular to the ground. By comparing his measurement to another made a distance away, Eratosthenes was able to calculate the circumference of the earth. How Big is Earth provides an online learning environment where students do science the same way Eratosthenes did. A notable project in which this was done was The Eratosthenes Project, conducted in 2005 as part of the World Year of Physics; in fact, we will be drawing on the teacher's guide developed by that project.How Big Is Earth? expands on the Eratosthenes project by providing an online learning environment provided by the iCollaboratory, www.icollaboratory.org, where teachers and students from Sweden, China, Nepal, Russia, Morocco, and the United States collaborate, share data, and reflect on their learning of science and astronomy. They are sharing their information and discussing their ideas/brainstorming the solutions in a discussion forum. There is an ongoing database of student measurements and another database to collect data on both teacher and student learning from surveys, discussions, and self-reflection done online.We will share our research about the kinds of learning that takes place only in global collaborations.The entrance address for the iCollaboratory is http://www.icollaboratory.org.

Interacting with Petabytes of Earth Science Data using Jupyter Notebooks, IPython Widgets and Google Earth Engine

Science.gov (United States)

Erickson, T. A.; Granger, B.; Grout, J.; Corlay, S.

2017-12-01

The volume of Earth science data gathered from satellites, aircraft, drones, and field instruments continues to increase. For many scientific questions in the Earth sciences, managing this large volume of data is a barrier to progress, as it is difficult to explore and analyze large volumes of data using the traditional paradigm of downloading datasets to a local computer for analysis. Furthermore, methods for communicating Earth science algorithms that operate on large datasets in an easily understandable and reproducible way are needed. Here we describe a system for developing, interacting, and sharing well-documented Earth Science algorithms that combines existing software components: Jupyter Notebook: An open-source, web-based environment that supports documents that combine code and computational results with text narrative, mathematics, images, and other media. These notebooks provide an environment for interactive exploration of data and development of well documented algorithms. Jupyter Widgets / ipyleaflet: An architecture for creating interactive user interface controls (such as sliders, text boxes, etc.) in Jupyter Notebooks that communicate with Python code. This architecture includes a default set of UI controls (sliders, dropboxes, etc.) as well as APIs for building custom UI controls. The ipyleaflet project is one example that offers a custom interactive map control that allows a user to display and manipulate geographic data within the Jupyter Notebook. Google Earth Engine: A cloud-based geospatial analysis platform that provides access to petabytes of Earth science data via a Python API. The combination of Jupyter Notebooks, Jupyter Widgets, ipyleaflet, and Google Earth Engine makes it possible to explore and analyze massive Earth science datasets via a web browser, in an environment suitable for interactive exploration, teaching, and sharing. Using these environments can make Earth science analyses easier to understand and reproducible, which may

Laurel Clark Earth Camp: Building a Framework for Teacher and Student Understanding of Earth Systems

Science.gov (United States)

Colodner, D.; Buxner, S.; Schwartz, K.; Orchard, A.; Titcomb, A.; King, B.; Baldridge, A.; Thomas-Hilburn, H.; Crown, D. A.

2013-04-01

Laurel Clark Earth Camp is designed to inspire teachers and students to study their world through field experiences, remote sensing investigations, and hands on exploration, all of which lend context to scientific inquiry. In three different programs (for middle school students, for high school students, and for teachers) participants are challenged to understand Earth processes from the perspectives of both on-the ground inspection and from examination of satellite images, and use those multiple perspectives to determine best practices on both a societal and individual scale. Earth Camp is a field-based program that takes place both in the “natural” and built environment. Middle School Earth Camp introduces students to a variety of environmental science, engineering, technology, and societal approaches to sustainability. High School Earth Camp explores ecology and water resources from southern Arizona to eastern Utah, including a 5 day rafting trip. In both camps, students compare environmental change observed through repeat photography on the ground to changes observed from space. Students are encouraged to utilize their camp experience in considering their future course of study, career objectives, and lifestyle choices. During Earth Camp for Educators, teachers participate in a series of weekend workshops to explore relevant environmental science practices, including water quality testing, biodiversity surveys, water and light audits, and remote sensing. Teachers engage students, both in school and after school, in scientific investigations with this broad based set of tools. Earth Stories from Space is a website that will assist in developing skills and comfort in analyzing change over time and space using remotely sensed images. Through this three-year NASA funded program, participants will appreciate the importance of scale and perspective in understanding Earth systems and become inspired to make choices that protect the environment.

Hands On Earth Science.

Science.gov (United States)

Weisgarber, Sherry L.; Van Doren, Lisa; Hackathorn, Merrianne; Hannibal, Joseph T.; Hansgen, Richard

This publication is a collection of 13 hands-on activities that focus on earth science-related activities and involve students in learning about growing crystals, tectonics, fossils, rock and minerals, modeling Ohio geology, geologic time, determining true north, and constructing scale-models of the Earth-moon system. Each activity contains…

Recovering heavy rare earth metals from magnet scrap

Science.gov (United States)

Ott, Ryan T.; McCallum, Ralph W.; Jones, Lawrence L.

2017-08-08

A method of treating rare earth metal-bearing permanent magnet scrap, waste or other material in a manner to recover the heavy rare earth metal content separately from the light rare earth metal content. The heavy rare earth metal content can be recovered either as a heavy rare earth metal-enriched iron based alloy or as a heavy rare earth metal based alloy.

Google Earth: A Virtual Globe for Elementary Geography

Science.gov (United States)

Britt, Judy; LaFontaine, Gus

2009-01-01

Originally called Earth Viewer in 2004, Google Earth was the first virtual globe easily available to the ordinary user of the Internet. Google Earth, at earth.google.com, is a free, 3-dimensional computer model of Earth, but that means more than just a large collection of pretty pictures. It allows the viewer to "fly" anywhere on Earth "to view…

Properties of an Earth-like planet orbiting a Sun-like star: Earth observed by the EPOXI mission.

Science.gov (United States)

Livengood, Timothy A; Deming, L Drake; A'hearn, Michael F; Charbonneau, David; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Meadows, Victoria S; Robinson, Tyler D; Seager, Sara; Wellnitz, Dennis D

2011-11-01

NASA's EPOXI mission observed the disc-integrated Earth and Moon to test techniques for reconnoitering extrasolar terrestrial planets, using the Deep Impact flyby spacecraft to observe Earth at the beginning and end of Northern Hemisphere spring, 2008, from a range of ∼1/6 to 1/3 AU. These observations furnish high-precision and high-cadence empirical photometry and spectroscopy of Earth, suitable as "ground truth" for numerically simulating realistic observational scenarios for an Earth-like exoplanet with finite signal-to-noise ratio. Earth was observed at near-equatorial sub-spacecraft latitude on 18-19 March, 28-29 May, and 4-5 June (UT), in the range of 372-4540 nm wavelength with low visible resolving power (λ/Δλ=5-13) and moderate IR resolving power (λ/Δλ=215-730). Spectrophotometry in seven filters yields light curves at ∼372-948 nm filter-averaged wavelength, modulated by Earth's rotation with peak-to-peak amplitude of ≤20%. The spatially resolved Sun glint is a minor contributor to disc-integrated reflectance. Spectroscopy at 1100-4540 nm reveals gaseous water and carbon dioxide, with minor features of molecular oxygen, methane, and nitrous oxide. One-day changes in global cloud cover resulted in differences between the light curve beginning and end of ≤5%. The light curve of a lunar transit of Earth on 29 May is color-dependent due to the Moon's red spectrum partially occulting Earth's relatively blue spectrum. The "vegetation red edge" spectral contrast observed between two long-wavelength visible/near-IR bands is ambiguous, not clearly distinguishing between the verdant Earth diluted by cloud cover versus the desolate mineral regolith of the Moon. Spectrophotometry in at least one other comparison band at short wavelength is required to distinguish between Earth-like and Moon-like surfaces in reconnaissance observations. However, measurements at 850 nm alone, the high-reflectance side of the red edge, could be sufficient to

EOS Reference Handbook 1999: A Guide to NASA's Earth Science Enterprise and the Earth Observing System

Science.gov (United States)

King, M. D. (Editor); Greenstone, R. (Editor)

2000-01-01

The content of this handbook includes Earth Science Enterprise; The Earth Observing System; EOS Data and Information System (EOSDIS); Data and Information Policy; Pathfinder Data Sets; Earth Science Information Partners and the Working Prototype-Federation; EOS Data Quality: Calibration and Validation; Education Programs; International Cooperation; Interagency Coordination; Mission Elements; EOS Instruments; EOS Interdisciplinary Science Investigations; and Points-of-Contact.

Next-generation digital earth

NARCIS (Netherlands)

Goodchild, M.F.; Guo, H.; Annoni, A.; Bian, L.; Bie, de K.; Campbell, F.; Craglia, M.; Ehlers, M.; Genderen, van J.; Skidmore, A.K.; Wang, C.; Woodgate, P.

2012-01-01

A speech of then-Vice President Al Gore in 1998 created a vision for a Digital Earth, and played a role in stimulating the development of a first generation of virtual globes, typified by Google Earth, that achieved many but not all the elements of this vision. The technical achievements of Google

iSTEM: Celebrating Earth Day with Sustainability

Science.gov (United States)

Sibley, Amanda; Kurz, Terri L.

2014-01-01

Earth Day is celebrated annually on April 22. Teachers often commemorate Earth Day with their classes by planting trees, discussing important conservation topics (such as recycling or preventing pollution), and encouraging students to take care of planet Earth. To promote observance of Earth Day in an intermediate elementary school classroom, this…

Earth Institute at Columbia University ADVANCE Program: Addressing Needs for Women in Earth and Environmental Sciences

Science.gov (United States)

Bell, R. E.; Cane, M.; Mutter, J.; Miller, R.; Pfirman, S.; Laird, J.

2004-12-01

The Earth Institute has received a major NSF ADVANCE grant targeted at increasing the participation and advancement of women scientists and engineers in the Academy through institutional transformation. The Earth Institute at Columbia University includes 9 research institutes including Lamont-Doherty Earth Observatory, Center for Environmental Research and Conservation (CERC), Center for International Earth Science Information Network (CIESIN), International Research Institute (IRI) for Climate Prediction, Earth Engineering Center, NASA-Goddard Institute for Space Studies, Center for Risks and Hazards, Center for Globalization and Sustainable Development, and Center for Global Health and Economic Development and six academic departments including Ecology, Evolution and Environmental Biology (E3B, School of Arts and Sciences), Earth and Environmental Engineering (DEEE, School of Engineering and Applied Sciences), Department of Environmental Health (School of Public Health), Department of Earth and Environmental Sciences (DEES, School of Arts and Sciences), Department of International and Public Affairs (School of International and Policy Affairs), and Barnard College Department of Environmental Science. The Earth Institute at Columbia University's ADVANCE program is based both on a study of the status of women at Columbia and research on the progression of women in science elsewhere. The five major targets of the Columbia ADVANCE program are to (1) change the demographics of the faculty through intelligent hiring practices, (2) provide support to women scientists through difficult life transitions including elder care and adoption or birth of a child, (3) enhance mentoring and networking opportunities, (4) implement transparent promotion procedures and policies, and (5) conduct an institutional self study. The Earth Institute ADVANCE program is unique in that it addresses issues that tend to manifest themselves in the earth and environmental fields, such as extended

Defect structure of cubic solid solutions of alkaline earth and rare earth fluorides

NARCIS (Netherlands)

DenHartog, HW

1996-01-01

In this paper we will consider the disorder in some cubic solid solutions consisting of one of the alkaline earth fluorides and one of the rare earth fluorides. This is an attractive group of model materials, because these materials have a rather simple overall cubic structure. We will discuss the

Keeping Earth at work: Using thermodynamics to develop a holistic theory of the Earth system

Science.gov (United States)

Kleidon, Axel

2010-05-01

The Earth system is unique among terrestrial planets in that it is maintained in a state far from thermodynamic equilibrium. Practically all processes are irreversible in their nature, thereby producing entropy, and these would act to destroy this state of disequilibrium. In order to maintain disequilibrium in steady state, driving forces are required that perform the work to maintain the Earth system in a state far from equilibrium. To characterize the functioning of the Earth system and the interactions among its subsystems we need to consider all terms of the first and second law of thermodynamics. While the global energy balance is well established in climatology, the global entropy and work balances receive little, if any, attention. Here I will present first steps in developing a holistic theory of the Earth system including quantifications of the relevant terms that is based on the first and second laws of thermodynamics. This theory allows us to compare the significance of different processes in driving and maintaining disequilibrium, allows us to explore interactions by investigating the role of power transfer among processes, and specifically illustrate the significance of life in driving planetary disequilibrium. Furthermore, the global work balance demonstrates the significant impact of human activity and it provides an estimate for the availability of renewable sources of free energy within the Earth system. Hence, I conclude that a holistic thermodynamic theory of the Earth system is not just some academic exercise of marginal use, but essential for a profound understanding of the Earth system and its response to change.

The Crew Earth Observations Experiment: Earth System Science from the ISS

Science.gov (United States)

Stefanov, William L.; Evans, Cynthia A.; Robinson, Julie A.; Wilkinson, M. Justin

2007-01-01

This viewgraph presentation reviews the use of Astronaut Photography (AP) as taken from the International Space Station (ISS) in Earth System Science (ESS). Included are slides showing basic remote sensing theory, data characteristics of astronaut photography, astronaut training and operations, crew Earth observations group, targeting sites and acquisition, cataloging and database, analysis and applications for ESS, image analysis of particular interest urban areas, megafans, deltas, coral reefs. There are examples of the photographs and the analysis.

Earth System Science Project

Science.gov (United States)

Rutherford, Sandra; Coffman, Margaret

2004-01-01

For several decades, science teachers have used bottles for classroom projects designed to teach students about biology. Bottle projects do not have to just focus on biology, however. These projects can also be used to engage students in Earth science topics. This article describes the Earth System Science Project, which was adapted and developed…

Flexible Description and Adaptive Processing of Earth Observation Data through the BigEarth Platform

Science.gov (United States)

Gorgan, Dorian; Bacu, Victor; Stefanut, Teodor; Nandra, Cosmin; Mihon, Danut

2016-04-01

The Earth Observation data repositories extending periodically by several terabytes become a critical issue for organizations. The management of the storage capacity of such big datasets, accessing policy, data protection, searching, and complex processing require high costs that impose efficient solutions to balance the cost and value of data. Data can create value only when it is used, and the data protection has to be oriented toward allowing innovation that sometimes depends on creative people, which achieve unexpected valuable results through a flexible and adaptive manner. The users need to describe and experiment themselves different complex algorithms through analytics in order to valorize data. The analytics uses descriptive and predictive models to gain valuable knowledge and information from data analysis. Possible solutions for advanced processing of big Earth Observation data are given by the HPC platforms such as cloud. With platforms becoming more complex and heterogeneous, the developing of applications is even harder and the efficient mapping of these applications to a suitable and optimum platform, working on huge distributed data repositories, is challenging and complex as well, even by using specialized software services. From the user point of view, an optimum environment gives acceptable execution times, offers a high level of usability by hiding the complexity of computing infrastructure, and supports an open accessibility and control to application entities and functionality. The BigEarth platform [1] supports the entire flow of flexible description of processing by basic operators and adaptive execution over cloud infrastructure [2]. The basic modules of the pipeline such as the KEOPS [3] set of basic operators, the WorDeL language [4], the Planner for sequential and parallel processing, and the Executor through virtual machines, are detailed as the main components of the BigEarth platform [5]. The presentation exemplifies the development

Comparison of Freshmen's Cognitive Frame about 'Crisis of the Earth' upon Taking the Earth Science 1 in High School

Science.gov (United States)

Chung, Duk Ho; Park, Seon Ok

2016-04-01

The purpose of this study is to demonstrate if freshmen's cognitive frame about 'Crisis of the Earth' upon taking the Earth science 1I in high school reflects the school curriculum. The data was collected from 67 freshmen who'd graduated high school in formal education. They expressed 'Crisis of the Earth' as a painting with explanation and then we extracted units of meaning from paintings, respectively. We analyzed the words and frame using the Semantic Network Analysis. The result is as follows; First, as every participant forms the cognitive frame for the crisis of the Earth, it is shown that they connect each part which that composes the global environment and realize it as the changing relation with interaction. Secondly, forming a cognitive frame regarding crisis of the Earth, both groups connect it with human endeavor. Especially, it seems that the group of participants who finished Earth Science 1 fully reflects the course of the formal education. It is necessary to make the students recognize it from a universal point of view, not only from the Earth. Also, much effort is required in order to enlighten about the appropriateness regarding problem-solving of the Earth and expand their mind as time changes. Keywords : Earth Science 1, cognitive frame, crisis of the earth, semantic network analysis

Discover Earth: an earth system science program for libraries and their communities

Science.gov (United States)

Dusenbery, P.

2011-12-01

The view from space has deepened our understanding of Earth as a global, dynamic system. Instruments on satellites and spacecraft, coupled with advances in ground-based research, have provided us with astonishing new perspectives of our planet. Now more than ever, enhancing the public's understanding of Earth's physical and biological systems is vital to helping citizens make informed policy decisions especially when they are faced with the consequences of global climate change. While the focus for education reform is on school improvement, there is considerable research that supports the role that out-of-school experiences can play in student achievement. Libraries provide an untapped resource for engaging underserved youth and their families in fostering an appreciation and deeper understanding of science and technology topics. The Space Science Institute's National Center for Interactive Learning (NCIL) in partnership with the American Library Association (ALA), the Lunar and Planetary Institute (LPI), and the National Girls Collaborative Project (NGCP) have received funding from NSF to develop a national project called the STAR Library Education Network: a hands-on learning program for libraries and their communities (or STAR-Net for short). STAR stands for Science-Technology, Activities and Resources. STAR-Net includes two exhibitions: Discover Earth and Discover Tech. The Discover Earth exhibition will focus on local earth science topics-such as weather, water cycle, and ecosystem changes-as well as a global view of our changing planet. The main take-away message (or Big Idea) for this exhibition is that the global environment changes - and is changed by - the host community's local environment. The project team is testing whether this approach will be a good strategy for engaging the public, especially in rural America. This presentation will provide an overview of the Discover Earth project and how it is integrating climate change ideas into the exhibit

Modelling ground rupture due to groundwater withdrawal: applications to test cases in China and Mexico

Science.gov (United States)

Franceschini, A.; Teatini, P.; Janna, C.; Ferronato, M.; Gambolati, G.; Ye, S.; Carreón-Freyre, D.

2015-11-01

The stress variation induced by aquifer overdraft in sedimentary basins with shallow bedrock may cause rupture in the form of pre-existing fault activation or earth fissure generation. The process is causing major detrimental effects on a many areas in China and Mexico. Ruptures yield discontinuity in both displacement and stress field that classic continuous finite element (FE) models cannot address. Interface finite elements (IE), typically used in contact mechanics, may be of great help and are implemented herein to simulate the fault geomechanical behaviour. Two main approaches, i.e. Penalty and Lagrangian, are developed to enforce the contact condition on the element interface. The incorporation of IE incorporation into a three-dimensional (3-D) FE geomechanical simulator shows that the Lagrangian approach is numerically more robust and stable than the Penalty, thus providing more reliable solutions. Furthermore, the use of a Newton-Raphson scheme to deal with the non-linear elasto-plastic fault behaviour allows for quadratic convergence. The FE - IE model is applied to investigate the likely ground rupture in realistic 3-D geologic settings. The case studies are representative of the City of Wuxi in the Jiangsu Province (China), and of the City of Queretaro, Mexico, where significant land subsidence has been accompanied by the generation of several earth fissures jeopardizing the stability and integrity of the overland structures and infrastructure.

Subsidence characterization and modeling for engineered facilities in Arizona, USA

Directory of Open Access Journals (Sweden)

M. L. Rucker

2015-11-01

Full Text Available Several engineered facilities located on deep alluvial basins in southern Arizona, including flood retention structures (FRS and a coal ash disposal facility, have been impacted by up to as much as 1.8 m of differential land subsidence and associated earth fissuring. Compressible basin alluvium depths are as deep as about 300 m, and historic groundwater level declines due to pumping range from 60 to more than 100 m at these facilities. Addressing earth fissure-inducing ground strain has required alluvium modulus characterization to support finite element modeling. The authors have developed Percolation Theory-based methodologies to use effective stress and generalized geo-material types to estimate alluvium modulus as a function of alluvium lithology, depth and groundwater level. Alluvial material modulus behavior may be characterized as high modulus gravel-dominated, low modulus sand-dominated, or very low modulus fines-dominated (silts and clays alluvium. Applied at specific aquifer stress points, such as significant pumping wells, this parameter characterization and quantification facilitates subsidence magnitude modeling at its' sources. Modeled subsidence is then propagated over time across the basin from the source(s using a time delay exponential decay function similar to the soil mechanics consolidation coefficient, only applied laterally. This approach has expanded subsidence modeling capabilities on scales of engineered facilities of less than 2 to more than 15 km.

Introducing Earth's Orbital Eccentricity

Science.gov (United States)

Oostra, Benjamin

2015-01-01

Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

NASA's Earth science flight program status

Science.gov (United States)

Neeck, Steven P.; Volz, Stephen M.

2010-10-01

NASA's strategic goal to "advance scientific understanding of the changing Earth system to meet societal needs" continues the agency's legacy of expanding human knowledge of the Earth through space activities, as mandated by the National Aeronautics and Space Act of 1958. Over the past 50 years, NASA has been the world leader in developing space-based Earth observing systems and capabilities that have fundamentally changed our view of our planet and have defined Earth system science. The U.S. National Research Council report "Earth Observations from Space: The First 50 Years of Scientific Achievements" published in 2008 by the National Academy of Sciences articulates those key achievements and the evolution of the space observing capabilities, looking forward to growing potential to address Earth science questions and enable an abundance of practical applications. NASA's Earth science program is an end-to-end one that encompasses the development of observational techniques and the instrument technology needed to implement them. This includes laboratory testing and demonstration from surface, airborne, or space-based platforms; research to increase basic process knowledge; incorporation of results into complex computational models to more fully characterize the present state and future evolution of the Earth system; and development of partnerships with national and international organizations that can use the generated information in environmental forecasting and in policy, business, and management decisions. Currently, NASA's Earth Science Division (ESD) has 14 operating Earth science space missions with 6 in development and 18 under study or in technology risk reduction. Two Tier 2 Decadal Survey climate-focused missions, Active Sensing of CO2 Emissions over Nights, Days and Seasons (ASCENDS) and Surface Water and Ocean Topography (SWOT), have been identified in conjunction with the U.S. Global Change Research Program and initiated for launch in the 2019

Earth-Affecting Solar Causes Observatory (EASCO): a mission at the Sun-Earth L5

DEFF Research Database (Denmark)

Gopalswamy, Nat; Davila, Joseph M.; Auchère, Frédéric

2011-01-01

Observatory (STEREO) missions, but these missions lacked some key measurements: STEREO did not have a magnetograph; SOHO did not have in-situ magnetometer. SOHO and other imagers such as the Solar Mass Ejection Imager (SMEI) located on the Sun-Earth line are also not well-suited to measure Earth-directed CMEs....... The Earth-Affecting Solar Causes Observatory (EASCO) is a proposed mission to be located at the Sun-Earth L5 that overcomes these deficiencies. The mission concept was recently studied at the Mission Design Laboratory (MDL), NASA Goddard Space Flight Center, to see how the mission can be implemented....... The study found that the scientific payload (seven remote-sensing and three in-situ instruments) can be readily accommodated and can be launched using an intermediate size vehicle; a hybrid propulsion system consisting of a Xenon ion thruster and hydrazine has been found to be adequate to place the payload...

Sintered cobalt-rare earth intermetallic product

International Nuclear Information System (INIS)

Benz, M.C.

1975-01-01

A process is described for preparing novel sintered cobalt--rare earth intermetallic products which can be magnetized to form permanent magnets having stable improved magnetic properties. A cobalt--rare earth metal alloy is formed having a composition which at sintering temperature falls outside the composition covered by the single Co 5 R intermetallic phase on the rare earth richer side. The alloy contains a major amount of the Co 5 R intermetallic phase and a second solid CoR phase which is richer in rare earth metal content than the Co 5 R phase. The specific cobalt and rare earth metal content of the alloy is substantially the same as that desired in the sintered product. The alloy, in particulate form, is pressed into compacts and sintered to the desired density. The sintered product is comprised of a major amount of the Co 5 R solid intermetallic phase and up to about 35 percent of the product of the second solid CoR intermetallic phase which is richer in rare earth metal content than the Co 5 R phase

HfO2 - rare earth oxide systems in the region with high content of rare earth oxide

International Nuclear Information System (INIS)

Shevchenko, A.V.; Lopato, L.M.

1982-01-01

Using the methods of annealing and hardenings (10 2 -10 4 deg/s cooling rate) and differential thermal analysis elements of state diagrams of HfO 2 - rare earth oxide (rare earths-La, Pr, Nd, Sm, Gd, Tb, Dy, Y, Er, Yb, Lu, Sc) systems from 1800 deg C up to melting in the range of 60-100 mol% rare earth oxide concentration were constructed. Regularities of HfQ 2 addition effect on high-temperature polymorphic transformations of rare earth oxides were studied. Results of investigation were discussed from viewpoint of crystal chemistry

Behaviour of Rare Earth Elements during the Earth's core formation

Science.gov (United States)

Faure, Pierre; Bouhifd, Mohamed Ali; Boyet, Maud; Hammouda, Tahar; Manthilake, Geeth

2017-04-01

Rare Earth Elements (REE) are classified in the refractory group, which means that they have a high temperature condensation and their volatility-controlled fractionation is limited to high-temperature processes. Anomalies have been measured for Eu, Yb and Sm, which are the REE with the lowest condensation temperatures in CAIs and chondrules (e.g. [1]). REE are particularly abundant in the sulfides of enstatite chondrites, 100 to 1000 times the CI value [e.g. 2,3], proving that these elements are not strictly lithophile under extremely reducing conditions. However by investigating experimentally the impact of Earth's core formation on the behavior of Sm and Nd, we have shown the absence of fractionation between Sm and Nd during the segregation of the metallic phase [4]. Recently, Wohlers and Wood [5] proposed that Nd and Sm could be fractionated in presence of a S-rich alloy phase. However, their results were obtained at pressure and temperature conditions below the plausible conditions of the Earth's core formation. Clearly, large pressure range needs to be covered before well-constrained model can be expected. Furthermore, our preliminary metal-silicate partitioning results show that Ce and Eu have higher metal/silicate partition coefficients than their neighboring elements, and that the presence of sulphur enhances the relative difference between partition coefficients. In this presentation, we will present and discuss new metal-silicate partition coefficients of all REE at a deep magma ocean at pressures ranging from those of the uppermost upper mantle ( 5 GPa) to a maximum pressure expected in the range of 20 GPa, temperatures ranging from 2500 to about 3000 K, and oxygen fugacities within IW-1 to IW-5 (1 to 5 orders of magnitude lower than the iron-wüstite buffer). We will discuss the effect of S, as well as the effect of H2O on the behaviour of REE during the Earth's core formation: recent models suggest that contrary to currently accepted beliefs, the

Production of rare earth-silicon-iron alloys

International Nuclear Information System (INIS)

Mehra, O.K.; Bose, D.K.; Gupta, C.K.

1987-01-01

At Metallurgy Division, BARC, improved procedures for producing rare earth-silicon alloys have been investigated. In these methods, reduction of mixed rare earth oxide by a ferro-silicon and aluminium mixture in combination with CaO-MgO flux/CaO-CaF 2 flux have been tried to prepare an alloy product with a higher rare earth recovery at a higher rare earth content than the present commercial production method. The rare earth recovery using CaO-CaF 2 was 85 per cent while in the case of CaO-MgO flux it was 76 per cent. The corresponding rare earth contents in the alloy correspond to 40 per cent and 55 per cent by weight respectively. (author)

Earth Systems Science: An Analytic Framework

Science.gov (United States)

Finley, Fred N.; Nam, Younkeyong; Oughton, John

2011-01-01

Earth Systems Science (ESS) is emerging rapidly as a discipline and is being used to replace the older earth science education that has been taught as unrelated disciplines--geology, meteorology, astronomy, and oceanography. ESS is complex and is based on the idea that the earth can be understood as a set of interacting natural and social systems.…

Earth Science Literacy: Building Community Consensus

Science.gov (United States)

Wysession, M.; Ladue, N.; Budd, D.; Campbell, K.; Conklin, M.; Lewis, G.; Raynolds, R.; Ridky, R.; Ross, R.; Taber, J.; Tewksbury, B.; Tuddenham, P.

2008-12-01

During 2008, the Earth Sciences Literacy Initiative (ESLI) constructed a framework of earth science "Big Ideas" and "Supporting Concepts". Following the examples of recent literacy efforts in the ocean, atmosphere and climate research communities, ESLI has distilled the fundamental understandings of the earth science community into a document that all members of the community will be able to refer to when working with educators, policy-makers, the press and members of the general public. This document is currently in draft form for review and will be published for public distribution in 2009. ESLI began with the construction of an organizing committee of a dozen people who represent a wide array of earth science backgrounds. This group then organized and ran two workshops in 2008: a 2-week online content workshop and a 3-day intensive writing workshop. For both workshops, participants were chosen so as to cover the full breadth of earth science related to the solid earth, surficial processes, and fresh-water hydrology. The asynchronous online workshop included 350 scientists and educators participating from around the world and was a powerful way to gather ideas and information while retaining a written record of all interactions. The writing workshop included 35 scientists, educators and agency representatives to codify the extensive input of the online workshop. Since September, 2008, drafts of the ESLI literacy framework have been circulated through many different channels to make sure that the document accurately reflects the current understandings of earth scientists and to ensure that it is widely accepted and adopted by the earth science communities.

USGEO Common Framework For Earth Observation Data

Science.gov (United States)

Walter, J.; de la Beaujardiere, J.; Bristol, S.

2015-12-01

The United States Group on Earth Observations (USGEO) Data Management Working Group (DMWG) is an interagency body established by the White House Office of Science and Technology Policy (OSTP). The primary purpose of this group is to foster interagency cooperation and collaboration for improving the life cycle data management practices and interoperability of federally held earth observation data consistent with White House documents including the National Strategy for Civil Earth Observations, the National Plan for Civil Earth Observations, and the May 2013 Executive Order on Open Data (M-13-13). The members of the USGEO DMWG are working on developing a Common Framework for Earth Observation Data that consists of recommended standards and approaches for realizing these goals as well as improving the discoverability, accessibility, and usability of federally held earth observation data. These recommendations will also guide work being performed under the Big Earth Data Initiative (BEDI). This talk will summarize the Common Framework, the philosophy behind it, and next steps forward.

Earth current monitoring circuit for inductive loads

CERN Document Server

Montabonnet, V; Thurel, Y; Cussac, P

2010-01-01

The search for higher magnetic fields in particle accelerators increasingly demands the use of superconducting magnets. This magnet technology has a large amount of magnetic energy storage during operation at relatively high currents. As such, many monitoring and protection systems are required to safely operate the magnet, including the monitoring of any leakage of current to earth in the superconducting magnet that indicates a failure of the insulation to earth. At low amplitude, the earth leakage current affects the magnetic field precision. At a higher level, the earth leakage current can additionally generate local losses which may definitively damage the magnet or its instrumentation. This paper presents an active earth fault current monitoring circuit, widely deployed in the converters for the CERN Large Hadron Collider (LHC) superconducting magnets. The circuit allows the detection of earth faults before energising the circuit as well as limiting any eventual earth fault current. The electrical stress...

Rare earth mobility in hydrothermal ore-forming systems

International Nuclear Information System (INIS)

Cornell, D.H.; Schade, J.; Scheepers, R.; Watkeys, M.K.

1988-01-01

Rocks and ores which form by magmatic processes display a range of chondrite-normalised rare earth profiles. One REE (rare earth elements) profile feature which seems unrelated to magmatic processes is the birdwing profile, in which both heavy and light rare earths are enriched relative to the middle rare earths. Birdwing rare earth profiles are an easily identified geochemical anomaly. It is proposed that rare earth geochemistry could be applied in geochemical prospecting for ore formed by hydrothermal processes. 5 figs

Sc, Y, La-Lu - Rare Earth Elements

International Nuclear Information System (INIS)

Anon.

1987-01-01

At present extensive efforts are being made in completing work on system number Rare Earth Elements. Part A is devoted to the occurrence of these elements on the earth and in the universe. Part B deals with the pure metals; the 7 volumes published cover the description of the separation from the raw materials, the preparation of pure metals,their uses and toxicology, the physical properties of nuclei, atoms, molecules, and isotopes; in addition the behavior of ions in solution and the electrochemical behavior of rare earth elements are described. The compounds are described in Part C. Part D with 6 volumes has been devoted to the description of coordination compounds and is completed. The volume ''Rare Earth Elements C 10'' deals with the rare earth tellurides, oxide tellurides, tellurates, telluride halides, tellurate halides, sulfide tellurides, selenide tellurides, and alkali rare earth tellurates. Another topic of this volume are the compounds of the rare earth elements with polonium. So far as meaningful and in accordance with all earlier volumes of ''Rare Earth Elements'' Series C, comparative data are presented in sections preceding treatment of the individual compounds and systems

Earth thermics

Energy Technology Data Exchange (ETDEWEB)

Ueda, M

1960-01-01

The thermodynamics of the Earth are described, including terrestrial heat flow, internal temperatures and thermal history. The value of the geothermal gradient has been considered to be 3/sup 0/C/100 m but measured values are slightly different. The values of terrestrial heat flow are relatively constant and are calculated be about 2.3 x 10 to the minus 6 cal/cm/sup 2/ sec (2.3 HFU). The Earth's internal temperature can be calculated from the adiabatic temperature gradient of adiabatic expansion. Using Simon's equation No. 9, a value of 2100-2500/sup 0/C is obtained, this is much lower than it was previously thought to be. The value of 2.3 HFU can easily be obtained from this internal temperature figure.

Non-rocket Earth-Moon transport system

Science.gov (United States)

Bolonkin, Alexander

2003-06-01

This paper proposes a new transportation system for travel between Earth and Moon. This transportation system uses mechanical energy transfer and requires only minimal energy, using an engine located on Earth. A cable directly connects a pole of the Earth through a drive station to the lunar surface_ The equation for an optimal equal stress cable for complex gravitational field of Earth-Moon has been derived that allows significantly lower cable masses. The required strength could be provided by cables constructed of carbon nanotubes or carbon whiskers. Some of the constraints on such a system are discussed.

The Earth is flat when personally significant experiences with the sphericity of the Earth are absent.

Science.gov (United States)

Carbon, Claus-Christian

2010-07-01

Participants with personal and without personal experiences with the Earth as a sphere estimated large-scale distances between six cities located on different continents. Cognitive distances were submitted to a specific multidimensional scaling algorithm in the 3D Euclidean space with the constraint that all cities had to lie on the same sphere. A simulation was run that calculated respective 3D configurations of the city positions for a wide range of radii of the proposed sphere. People who had personally experienced the Earth as a sphere, at least once in their lifetime, showed a clear optimal solution of the multidimensional scaling (MDS) routine with a mean radius deviating only 8% from the actual radius of the Earth. In contrast, the calculated configurations for people without any personal experience with the Earth as a sphere were compatible with a cognitive concept of a flat Earth. 2010 Elsevier B.V. All rights reserved.

Sensing Planet Earth - Chalmers' MOOCs on Earth observation

Science.gov (United States)

Hobiger, Thomas; Stöhr, Christian; Murtagh, Donal; Forkman, Peter; Galle, Bo; Mellquist, Johan; Soja, Maciej; Berg, Anders; Carvajal, Gisela; Eriksson, Leif; Haas, Rüdiger

2016-04-01

An increasing number of universities around the globe produce and conduct Massive Open Online Courses (MOOCs). In the beginning of 2016, Chalmers University of Technology ran two MOOCs on the topic of Earth observations on the edX platform. Both four week long courses were at introductory level and covered topics related to solid Earth, atmosphere, biosphere, hydrosphere and cryosphere. It was discussed how one can measure and trace global change and use remote sensing tools for disaster monitoring. Research has attempted to assess the learners' motivations to participate in MOOCs, but there is a need for further case studies about motivations, opportunities and challenges for teachers engaging in MOOC development. In our presentation, we are going to report about the experiences gained from both the MOOC production and the actual course run from the instructors' perspective. After brief introduction to MOOCs in general and at Chalmers in particular, we share experiences and challenges of developing lecture and assessment material, the video production and coordination efforts between and within different actors involved in the production process. Further, we reflect upon the actual run of the course including course statistics and feedback from the learners. We discuss issues such as learner activation and engagement with the material, teacher-learner and student-student interaction as well as the scalability of different learning activities. Finally, we will present our lessons-learned and conclusions on the applicability of MOOCs in the field of Earth science teaching.

External Fuel Tank, Clouds and Earth Limb

Science.gov (United States)

1991-01-01

It's fuel consumed, the expendable external fuel tank was jettisoned moments earlier from the Space Shuttle Atlantis and now begins its plunge back to Earth (20.5N, 36.0W). Backdropped against the void of space and the thin blue line of the Earth's airglow above the Earth Limb, the harshness of the blackness of space is softened by the fleeciness of Earth's cloud cover below.

A model study of the pollution effects of the first 3 months of the Holuhraun volcanic fissure: comparison with observations and air pollution effects

Directory of Open Access Journals (Sweden)

B. M. Steensen

2016-08-01

Full Text Available The volcanic fissure at Holuhraun, Iceland started at the end of August 2014 and continued for 6 months to the end of February 2015, with an extensive lava flow onto the Holuhraun plain. This event was associated with large SO2 emissions, amounting up to approximately 4.5 times the daily anthropogenic SO2 emitted from the 28 European Union countries, Norway, Switzerland and Iceland. In this paper we present results from EMEP/MSC-W model simulations to which we added 750 kg s−1 SO2 emissions at the Holuhraun plain from September to November (SON, testing three different emission heights. The three simulated SO2 concentrations, weighted with the OMI (Ozone Monitoring Instrument satellite averaging kernel, are found to be within 30 % of the satellite-observed SO2 column burden. Constraining the SO2 column burden with the satellite data while using the kernel along with the three simulated height distributions of SO2, we estimate that the median of the daily burdens may have been between 13 and 40 kt in the North Atlantic area under investigation. We suggest this to be the uncertainty in the satellite-derived burdens of SO2, mainly due to the unknown vertical distribution of SO2. Surface observations in Europe outside Iceland showed concentration increases up to > 500 µg m−3 SO2 from volcanic plumes passing. Three well identified episodes, where the plume crossed several countries, are compared in detail to surface measurements. For all events, the general timing of the observed concentration peaks compared quite well to the model results. The overall changes to the European SO2 budget due to the volcanic fissure are estimated. Three-monthly wet deposition (SON of SOx in the 28 European Union countries, Norway and Switzerland is found to be more than 30 % higher in the model simulation with Holuhraun emissions compared to a model simulation with no Holuhraun emissions. The largest increases, apart from extreme values on

A model study of the pollution effects of the first 3 months of the Holuhraun volcanic fissure: comparison with observations and air pollution effects

Science.gov (United States)

Steensen, Birthe Marie; Schulz, Michael; Theys, Nicolas; Fagerli, Hilde

2016-08-01

The volcanic fissure at Holuhraun, Iceland started at the end of August 2014 and continued for 6 months to the end of February 2015, with an extensive lava flow onto the Holuhraun plain. This event was associated with large SO2 emissions, amounting up to approximately 4.5 times the daily anthropogenic SO2 emitted from the 28 European Union countries, Norway, Switzerland and Iceland. In this paper we present results from EMEP/MSC-W model simulations to which we added 750 kg s-1 SO2 emissions at the Holuhraun plain from September to November (SON), testing three different emission heights. The three simulated SO2 concentrations, weighted with the OMI (Ozone Monitoring Instrument) satellite averaging kernel, are found to be within 30 % of the satellite-observed SO2 column burden. Constraining the SO2 column burden with the satellite data while using the kernel along with the three simulated height distributions of SO2, we estimate that the median of the daily burdens may have been between 13 and 40 kt in the North Atlantic area under investigation. We suggest this to be the uncertainty in the satellite-derived burdens of SO2, mainly due to the unknown vertical distribution of SO2. Surface observations in Europe outside Iceland showed concentration increases up to > 500 µg m-3 SO2 from volcanic plumes passing. Three well identified episodes, where the plume crossed several countries, are compared in detail to surface measurements. For all events, the general timing of the observed concentration peaks compared quite well to the model results. The overall changes to the European SO2 budget due to the volcanic fissure are estimated. Three-monthly wet deposition (SON) of SOx in the 28 European Union countries, Norway and Switzerland is found to be more than 30 % higher in the model simulation with Holuhraun emissions compared to a model simulation with no Holuhraun emissions. The largest increases, apart from extreme values on Iceland, are found on the coast of northern

The earth's shape and gravity

CERN Document Server

Garland, G D; Wilson, J T

2013-01-01

The Earth's Shape and Gravity focuses on the progress of the use of geophysical methods in investigating the interior of the earth and its shape. The publication first offers information on gravity, geophysics, geodesy, and geology and gravity measurements. Discussions focus on gravity measurements and reductions, potential and equipotential surfaces, absolute and relative measurements, and gravity networks. The text then elaborates on the shape of the sea-level surface and reduction of gravity observations. The text takes a look at gravity anomalies and structures in the earth's crust; interp

Rare earth elements behavior in Peruibe black mud

International Nuclear Information System (INIS)

Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da

2015-01-01

Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

Rare earth elements behavior in Peruibe black mud

Energy Technology Data Exchange (ETDEWEB)

Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da, E-mail: jeffkoy@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

Introductory mathematics for earth scientists

CERN Document Server

Yang, Xin-She

2009-01-01

Any quantitative work in earth sciences requires mathematical analysis and mathematical methods are essential to the modelling and analysis of the geological, geophysical and environmental processes involved. This book provides an introduction to the fundamental mathematics that all earth scientists need.

A 12-month clinical evaluation of pit-and-fissure sealants placed with and without etch-and-rinse and self-etch adhesive systems in newly-erupted teeth

Directory of Open Access Journals (Sweden)

Maryam Karami Nogourani

2012-06-01

Full Text Available OBJECTIVES: The objective of this one-year clinical study was to investigate the effect of two adhesive systems (Adper Single Bond, a two-step etch-and-rinse and Clearfil SE Bond, a two-step self-etch system on pit-and-fissure sealant retention in newly-erupted teeth. This study compared the success of the sealants in mesial and distopalatal grooves with and without these two adhesive systems. MATERIAL AND METHODS: In a clinical trial, 35 children aged 6-8 years undergoing sealant placement were recruited. This one-year clinical study scored 70 mesial and 70 distopalatal sealants of newly-erupted permanent maxillary first molar, with a split-mouth design. All children received sealant alone in one permanent maxillary molar tooth. Children were randomized into two groups. One group received Self-etch (Se bond plus sealant and the other group received Single Bond plus sealant in another permanent maxillary molar tooth. Clinical evaluation at 3, 6 and 12 months was performed and the retention was studied in terms of the success and failure. RESULTS: The success rate of sealant in the distopalatal groove, using SeB at 3, 6 and 12 months was 93.3% (95% CI: 68.0, 99.8, 73.3% (95% CI: 44.9, 92.2 and 66.7% (95% CI: 38.4, 88.2, respectively. It was greater than that of the distopalatal groove in SB group with a success rate of 62.5% (95% CI: 35.4, 84.8, 31.3% (95% CI: 11.8, 58.7 and 31.3% (95% CI: 11.8, 58.7, at the three evaluation periods. The success rate of sealant in the mesial groove using SeB was 86.6% (95% CI: 59.5, 98.3, 53.3% (95% CI: 26.6, 78.7 and 53.3% (95% CI: 26.6, 78.7, while this was 100% (95% CI: 79.4, 100.0, 81.3% (95% CI: 54.4, 96.0 and 81.3% (95% CI: 54.4, 96.0 using SB, at 3, 6 and 12-month evaluation periods. CONCLUSIONS: These results support the use of these two bonding agents in pit-and-fissure sealants under both isolated and contaminated conditions. Further, Se bond seemed to be less sensitive to moisture contamination.

Immersive Earth: Teaching Earth and Space with inexpensive immersive technology

Science.gov (United States)

Reiff, P. H.; Sumners, C.; Law, C. C.; Handron, K.

2003-12-01

In 1995 we pioneered "Space Update", the Digital Library for the rest of us", software that was so simple that a child could use it without a keyboard and yet would allow one-click updating of the daily earth and space science images without the dangers of having an open web browser on display. Thanks to NASA support, it allowed museums and schools to have a powerful exhibit for a tiny price. Over 40,000 disks in our series have been distributed so far to educators and the public. In 2003, with our partners we are again revolutionizing educational technology with a low-cost hardware and software solution to creating and displaying immersive content. Recently selected for funding as part of the REASoN competition, Immersive Earth is a partnership of scientists, museums, educators, and content providers. The hardware consists of a modest projector with a special fisheye lens to be used in an inflatable dome which many schools already have. This, coupled with a modest personal computer, can now easily project images and movies of earth and space, allows training students in 3-D content at a tiny fraction of the cost of a cave or fullscale dome theater. Another low-cost solution is the "Imove" system, where spherical movies can play on a personal computer, with the user changing the viewing direction with a joystick. We were the first to create immersive earth science shows, remain the leader in creating educational content that people want to see. We encourage people with "allsky" images or movies to bring it and see what it looks like inside a dome! Your content could be in our next show!

The Sun and Earth

Science.gov (United States)

Gopalswamy, Natchimuthuk

2012-01-01

Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

Propagation Velocity of Solid Earth Tides

Science.gov (United States)

Pathak, S.

2017-12-01

One of the significant considerations in most of the geodetic investigations is to take into account the outcome of Solid Earth tides on the location and its consequent impact on the time series of coordinates. In this research work, the propagation velocity resulting from the Solid Earth tides between the Indian stations is computed. Mean daily coordinates for the stations have been computed by applying static precise point positioning technique for a day. The computed coordinates are used as an input for computing the tidal displacements at the stations by Gravity method along three directions at 1-minute interval for 24 hours. Further the baseline distances are computed between four Indian stations. Computation of the propagation velocity for Solid Earth tides can be done by the virtue of study of the concurrent effect of it in-between the stations of identified baseline distance along with the time consumed by the tides for reaching from one station to another. The propagation velocity helps in distinguishing the impact at any station if the consequence at a known station for a specific time-period is known. Thus, with the knowledge of propagation velocity, the spatial and temporal effects of solid earth tides can be estimated with respect to a known station. As theoretically explained, the tides generated are due to the position of celestial bodies rotating about Earth. So the need of study is to observe the correlation of propagation velocity with the rotation speed of the Earth. The propagation velocity of Solid Earth tides comes out to be in the range of 440-470 m/s. This velocity comes out to be in a good agreement with the Earth's rotation speed.

Earth evolution as a thermal system

Science.gov (United States)

Tang, C.

2014-12-01

After fifty years of plate-tectonic theory, the reasons why earth sometime freezed as a snowball or sometime became lethally hot resulting in mass extinction remain enigmatic. This article proposes a new hypothesis on Earth evolution. The unbalance of heat between the input and output is considered as the driving force for the Earth evolution, the lithospheric expansion and associated uplift are the triggers, the self-organized progressive failure leading to collapse of the Earth are the amplifier, and the global scale response in terms of volcanism and magmatism is the globalizer. This shallow process of lithosphere may reach a critical state with a positive feedback loop, and result in the formation of no-plume original Large Igneous Provinces (NPOLIP) in a top-down pattern. Endothermic phase changes during de-compressive melting remove heat from and cool their surroundings, including the upper parts of the lithosphere. The huge loss of Earth's heat during eruption of LIPs, together with the endothermic cooling, may put the thermal cycle to an end and a new start of the cycle initiates. In summary, Earth drives itself to evolve in terms of thermal cycles. Global cooling and warming are the two stages of the many cycles during the Earth evolution. Glaciations are the extreme result of global cooling, whereas the LIPs, sometime accompanied with remarkable sea level dropping, are the extreme result of global warming, with a long recovering age, the interglacialstage, between them. They come and go as thermal cycle evolves, with climate warming, being caused by Earth itself rather than by external forces or human activities, as the most attractive prediction.

Sun-Earth Day Connects History, Culture and Science

Science.gov (United States)

Cline, T.; Thieman, J.

2003-12-01

The NASA Sun-Earth Connection Education forum annually promotes and event called Sun-Earth Day: a national celebration of the Sun, the space around the Earth (geospace), and how all of it affects life on our planet. For the past 3 years this event has provided a venue by which classrooms, museums, planetaria, and at NASA centers have had a sensational time sharing stories, images, and activities related to the Sun-Earth connections and the views o fthe Sun from Earth. Each year we select a different theme by which NASA Space Science can be further related to cross-curricular activities. Sun-Earth Day 2002, "Celebrate the Equinox", drew parallels between Native American Cultures and NASA's Sun-Earth Connection research via cultural stories, interviews, web links, activities and Native American participation. Sun-Earth Day 2003, "Live From the Aurora", shared the beauty of the Aurora through a variety of activities and stories related to perspectives of Northern Peoples. Sun-Earth Day 2004 will share the excitement of the transit of Venus through comparisons of Venus with Earth and Mars, calculations of the distances to nearby stars, and the use of transits to identify extra-solar planets. Finally, Sun-Earth Day 2005 will bring several of these themes together by turning our focus to the history and culture surrounding ancient observatories such as Chaco Canyon, Machu Picchu, and Chichen Itza.

Looking at the earth from space

Science.gov (United States)

Geller, Marvin A.

1988-01-01

Some of the scientific accomplishments attained in observing the earth from space are discussed. A brief overview of findings concerning the atmosphere, the oceans and sea ice, the solid earth, and the terrestrial hydrosphere and biosphere is presented, and six examples are examined in which space data have provided unique information enabling new knowledge concerning the workings of the earth to be derived. These examples concern stratospheric water vapor, hemispheric differences in surface and atmosphere parameters, Seasat altimeter mesoscale variability, variability of Antarctic sea ice, variations in the length of day, and spaceborne radar imaging of ancient rivers. Future space observations of the earth are briefly addressed.

Earth Surface Processes, Landforms and Sediment Deposits

Science.gov (United States)

Bridge, John; Demicco, Robert

Earth surface processes, landforms and sediment deposits are intimately related - involving erosion of rocks, generation of sediment, and transport and deposition of sediment through various Earth surface environments. These processes, and the landforms and deposits that they generate, have a fundamental bearing on engineering, environmental and public safety issues; on recovery of economic resources; and on our understanding of Earth history. This unique textbook brings together the traditional disciplines of sedimentology and geomorphology to explain Earth surface processes, landforms and sediment deposits in a comprehensive and integrated way. It is the ideal resource for a two-semester course in sedimentology, stratigraphy, geomorphology, and Earth surface processes from the intermediate undergraduate to beginning graduate level. The book is also accompanied by a website hosting illustrations and material on field and laboratory methods for measuring, describing and analyzing Earth surface processes, landforms and sediments.

Earth Science Education in Morocco

Science.gov (United States)

Bouabdelli, Mohamed

1999-05-01

The earth sciences are taught in twelve universities in Morocco and in three other institutions. In addition there are three more earth science research institutions. Earth science teaching has been taking place since 1957. The degree system is a four-year degree, split into two two-year blocks and geology is taught within the geology-biology programme for the first part of the degree. 'Classical' geology is taught in most universities, although applied geology degrees are also on offer in some universities. Recently-formed technical universities offer a more innovative approach to Earth Science Education. Teaching is in French, although school education is in Arabic. There is a need for a reform of the curriculum, although a lead is being taken by the technical universities. A new geological mapping programme promises new geological and mining discoveries in the country and prospects of employment for geology graduates.

Perbandingan intensitas warna CPO dengan menggunakan Bleaching Earth (BE) dan Spent Bleaching Earth (SBE) di PT. SMART Tbk.

OpenAIRE

Aritonang, Dwi Christina

2016-01-01

Comparative studies have been conducted on the effect of bleaching earth quality bleachibility power on CPO (crude palm oil). by using the tool Lovibond Tintometer model of F in PT Smart Tbk Medan – Belawan.From experiments obtained initial color with the CPO 20R - 20Y after addition Bleaching Earth and spent bleaching earth with the CPO each - each 10,2R - 20Y and 17.3R - 20Y . The results showed that purification using Bleaching Earth better than the purification of Spent Bleaching Earh ...

Free oscillation of the Earth

Directory of Open Access Journals (Sweden)

Y. Abedini

2000-06-01

Full Text Available   This work is a study of the Earths free oscillations considering a merge of solid and liquid model. At the turn of 19th century Geophysicists presented the theory of the free oscillations for a self-gravitating, isotropic and compressible sphere. Assuming a steel structure for an Earth size sphere, they predicted a period of oscillation of about 1 hour. About 50 years later, the free oscillations of stars was studied by Cowling and others. They classified the oscillation modes of the stars into acoustic and gravity modes on the basis of their driving forces. These are pressure and buoyancy forces respectively. The earliest measurements for the period of the free oscillations of the Earth was made by Benyove from a study of Kamchathca earthquake. Since then, the Geophysicists have been trying to provide a theoretical basis for these measurements. Recently, the theory concerning oscillations of celestial fluids is extended by Sobouti to include the possible oscillations of the Earthlike bodies. Using the same technique, we study the free oscillations of a spherically symmetric, non-rotating and elastic model for the Earth.   We used the actual data of the Earths interior structure in our numerical calculations. Numerical results show that there exist three distinct oscillation modes namely acoustic, gravity and toroidal modes. These modes are driven by pressure, buoyancy and shear forces respectively. The shear force is due to the elastic properties of the solid part of the Earth. Our numerical results are consistent with the seismic data recorded from earthquake measurements.

Student Learning of Complex Earth Systems: Conceptual Frameworks of Earth Systems and Instructional Design

Science.gov (United States)

Scherer, Hannah H.; Holder, Lauren; Herbert, Bruce

2017-01-01

Engaging students in authentic problem solving concerning environmental issues in near-surface complex Earth systems involves both developing student conceptualization of Earth as a system and applying that scientific knowledge using techniques that model those used by professionals. In this first paper of a two-part series, we review the state of…

LIMNOLOGICAL OPTOMETRY: EXAMINING EARTH'S EYE

Science.gov (United States)

In Thoreau's Walden, a lake is described as the landscape's most expressive feature and the earth's eye. Collectively, scientists are charged by society to assess, monitor, and remedy maladies of earth's eye in the same way optometrists maintain the health of the human eye. This ...

Teaching earth science

Science.gov (United States)

Alpha, Tau Rho; Diggles, Michael F.

1998-01-01

This CD-ROM contains 17 teaching tools: 16 interactive HyperCard 'stacks' and a printable model. They are separated into the following categories: Geologic Processes, Earthquakes and Faulting, and Map Projections and Globes. A 'navigation' stack, Earth Science, is provided as a 'launching' place from which to access all of the other stacks. You can also open the HyperCard Stacks folder and launch any of the 16 stacks yourself. In addition, a 17th tool, Earth and Tectonic Globes, is provided as a printable document. Each of the tools can be copied onto a 1.4-MB floppy disk and distributed freely.

The Rare Earth Magnet Industry and Rare Earth Price in China

Directory of Open Access Journals (Sweden)

Ding Kaihong

2014-07-01

Full Text Available In the past four years, the price of rare earth metal fluctuates sharply for many reasons. Currently, it has become more stable and more reasonable. This presentation is focused on the effect about the rare earth metal price. Some motor manufacturers have shifted from rare earth permanent magnet to ferrite magnet. Many motor manufacturers changed the design for the motor cooling system to make the motor function at a lower temperature. Thus the consumption of Dy can be markedly reduced. As for manufacturer of NdFeB magnet, we are also trying to optimize our process to reduce to dependence of HREE such as Dy and Tb. HS process have been introduced to solve the problem. With more and more people focusing and engaging on the REE industry, the price of REE will be more transparent without too many fluctuations. China is considering the problems of balancing the environment, energy sources, and labor sources. The application field about NdFeB such as wind turbine generator, HEV/EV, FA /OA is flourishing.

The Rare Earth Magnet Industry and Rare Earth Price in China

Science.gov (United States)

Ding, Kaihong

2014-07-01

In the past four years, the price of rare earth metal fluctuates sharply for many reasons. Currently, it has become more stable and more reasonable. This presentation is focused on the effect about the rare earth metal price. Some motor manufacturers have shifted from rare earth permanent magnet to ferrite magnet. Many motor manufacturers changed the design for the motor cooling system to make the motor function at a lower temperature. Thus the consumption of Dy can be markedly reduced. As for manufacturer of NdFeB magnet, we are also trying to optimize our process to reduce to dependence of HREE such as Dy and Tb. HS process have been introduced to solve the problem. With more and more people focusing and engaging on the REE industry, the price of REE will be more transparent without too many fluctuations. China is considering the problems of balancing the environment, energy sources, and labor sources. The application field about NdFeB such as wind turbine generator, HEV/EV, FA /OA is flourishing.

Rare Earth Metals: Resourcefulness and Recovery

Science.gov (United States)

Wang, Shijie

2013-10-01

When we appreciate the digital revolution carried over from the twentieth century with mobile communication and the Internet, and when we enjoy our high-tech lifestyle filled with iDevices, hybrid cars, wind turbines, and solar cells in this new century, we should also appreciate that all of these advanced products depend on rare earth metals to function. Although there are only 136,000 tons of annual worldwide demand, (Cho, Rare Earth Metals, Will We Have Enough?)1 rare earth metals are becoming such hot commodities on international markets, due to not only to their increasing uses, including in most critical military hardware, but also to Chinese growth, which accounts for 95% of global rare earth metal production. Hence, the 2013 technical calendar topic, planned by the TMS/Hydrometallurgy and Electrometallurgy Committee, is particularly relevant, with four articles (including this commentary) contributed to the JOM October Issue discussing rare earth metals' resourcefulness and recovery.

ELF-VLF communications through-the-Earth

Science.gov (United States)

Buettner, H. M.; Burke, G. J.; Didwall, E. M.; Holladay, G.; Lytle, R. J.

1985-06-01

We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified Earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-Earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constants of the rock, the noise characteristics, and modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

Preparation of rare earth fluorides from apatite concentrate

International Nuclear Information System (INIS)

Mulyarchuk, I.F.; Voloshchenko, M.V.; Zen'kovich, E.G.; Sumenkova, V.V.; AN Ukrainskoj SSR, Kiev. Inst. Problem Lit'ya)

1980-01-01

The processes of preparation of the rare earths element sum from apatite concentrate of the Khibins, connected with preliminary extraction of rare earth phosphates from nitric acid extract using solvent extraction or direct precipitation from the extract by solution of potassium and ammonium fluorides. The sequence of the processes of the first variant is the following: solvent extraction of rare earths by tributylphosphate from clarified nitric acid extract of apatite with subsequent reextraction of rare earths with water and precipitation of rare earth phosphates from aqueous solution during neutralization by ammonia. In case of fluoride preparation from rare earth phosphate the main attention is paid to precipitation and filtration of fluorides. Technological scheme and cost price of industry for the production of 1800 t of rare earth trifluorides a year are calculated. When taking account of TBP losses according to its solubility the industry cost price is 1O times lower the modern cost of rare earth fluorides

Spheres of Earth: An Introduction to Making Observations of Earth Using an Earth System's Science Approach. Student Guide

Science.gov (United States)

Graff, Paige Valderrama; Baker, Marshalyn (Editor); Graff, Trevor (Editor); Lindgren, Charlie (Editor); Mailhot, Michele (Editor); McCollum, Tim (Editor); Runco, Susan (Editor); Stefanov, William (Editor); Willis, Kim (Editor)

2010-01-01

Scientists from the Image Science and Analysis Laboratory (ISAL) at NASA's Johnson Space Center (JSC) work with astronauts onboard the International Space Station (ISS) who take images of Earth. Astronaut photographs, sometimes referred to as Crew Earth Observations, are taken using hand-held digital cameras onboard the ISS. These digital images allow scientists to study our Earth from the unique perspective of space. Astronauts have taken images of Earth since the 1960s. There is a database of over 900,000 astronaut photographs available at http://eol.jsc.nasa.gov . Images are requested by ISAL scientists at JSC and astronauts in space personally frame and acquire them from the Destiny Laboratory or other windows in the ISS. By having astronauts take images, they can specifically frame them according to a given request and need. For example, they can choose to use different lenses to vary the amount of area (field of view) an image will cover. Images can be taken at different times of the day which allows different lighting conditions to bring out or highlight certain features. The viewing angle at which an image is acquired can also be varied to show the same area from different perspectives. Pointing the camera straight down gives you a nadir shot. Pointing the camera at an angle to get a view across an area would be considered an oblique shot. Being able to change these variables makes astronaut photographs a unique and useful data set. Astronaut photographs are taken from the ISS from altitudes of 300 - 400 km (185 to 250 miles). One of the current cameras being used, the Nikon D3X digital camera, can take images using a 50, 100, 250, 400 or 800mm lens. These different lenses allow for a wider or narrower field of view. The higher the focal length (800mm for example) the narrower the field of view (less area will be covered). Higher focal lengths also show greater detail of the area on the surface being imaged. Scientists from the Image Science and Analysis

Avaliação do tratamento de fissura anal crônica com isossorbida tópica a 1% Evaluation of the treatment of chronic anal fissure with topical isosorbide 1%

Directory of Open Access Journals (Sweden)

Ana Carolina Lisboa Prudente

2010-12-01

Full Text Available INTRODUÇÃO: Fissuras anais crônicas são úlceras benignas, dolorosas, profundas. Ocorrem devido a trauma das fezes, hipertonia esfincteriana e pobre vascularização. Cirurgia é mais efetiva, porém com efeitos adversos (incontinência anal. Terapia conservadora consegue decréscimo transitório da pressão de repouso, cicatrizando muitas lesões, sem dano muscular. MÉTODOS: Objetivando avaliar tratamento de fissuras crônicas com isossorbida (ISO a 1% tópica, foi realizado um ensaio clínico, duplo-cego em pacientes do Serviço de Coloproctologia da Universidade Federal de Sergipe (UFS - Aracaju, Sergipe, durante um ano. Foram estudados 24 pacientes: 14 no Grupo 1 - creme com ISO, e 10 no Grupo 2 - placebo. Avaliaram-se comportamento da pressão de repouso, melhora da dor e grau de cicatrização das feridas com e sem ISO. RESULTADOS: Resultados mostraram que a fissura acometeu mais mulheres, a constipação foi observada em 58,3%. Quanto à dor, obteve-se menor intensidade no Grupo 2, mas sem significância. A cicatrização ao fim de 60 dias foi igual nos dois grupos (50%. Quanto às médias de pressão de repouso com 30 e 60 dias, houve queda no padrão em ambos os grupos, porém sem significância. Observou-se que pacientes curados foram os de maior redução de pressão de repouso. CONCLUSÃO: Concluiu-se que a ISO não modificou o padrão de resposta manométrica; todavia, houve melhora clínica importante nos dois grupos, cuja taxa de cicatrização foi equivalente.INTRODUCTION: Chronic anal fissures are deep, benign and painful ulcers. The involved factors are local trauma, sphinter hypertonia and poor blood flow. Surgery is gold standard treatment, but it causes fecal incontinence. Medical non-surgical therapy gets transitory resting pressure reduction and cure of lesions, without muscular damage. METHODS: In order to evaluate the treatment of chronic anal fissures using topical isossorbide (ISO 1%, a randomizated and double

Beyond seismic interferometry: imaging the earth's interior with virtual sources and receivers inside the earth

Science.gov (United States)

Wapenaar, C. P. A.; Van der Neut, J.; Thorbecke, J.; Broggini, F.; Slob, E. C.; Snieder, R.

2015-12-01

Imagine one could place seismic sources and receivers at any desired position inside the earth. Since the receivers would record the full wave field (direct waves, up- and downward reflections, multiples, etc.), this would give a wealth of information about the local structures, material properties and processes in the earth's interior. Although in reality one cannot place sources and receivers anywhere inside the earth, it appears to be possible to create virtual sources and receivers at any desired position, which accurately mimics the desired situation. The underlying method involves some major steps beyond standard seismic interferometry. With seismic interferometry, virtual sources can be created at the positions of physical receivers, assuming these receivers are illuminated isotropically. Our proposed method does not need physical receivers at the positions of the virtual sources; moreover, it does not require isotropic illumination. To create virtual sources and receivers anywhere inside the earth, it suffices to record the reflection response with physical sources and receivers at the earth's surface. We do not need detailed information about the medium parameters; it suffices to have an estimate of the direct waves between the virtual-source positions and the acquisition surface. With these prerequisites, our method can create virtual sources and receivers, anywhere inside the earth, which record the full wave field. The up- and downward reflections, multiples, etc. in the virtual responses are extracted directly from the reflection response at the surface. The retrieved virtual responses form an ideal starting point for accurate seismic imaging, characterization and monitoring.

Geo-neutrinos and earth's interior

International Nuclear Information System (INIS)

Fiorentini, Gianni; Lissia, Marcello; Mantovani, Fabio

2007-01-01

The deepest hole that has ever been dug is about 12 km deep. Geochemists analyze samples from the Earth's crust and from the top of the mantle. Seismology can reconstruct the density profile throughout all Earth, but not its composition. In this respect, our planet is mainly unexplored. Geo-neutrinos, the antineutrinos from the progenies of U, Th and 40 K decays in the Earth, bring to the surface information from the whole planet, concerning its content of natural radioactive elements. Their detection can shed light on the sources of the terrestrial heat flow, on the present composition, and on the origins of the Earth. Geo-neutrinos represent a new probe of our planet, which can be exploited as a consequence of two fundamental advances that occurred in the last few years: the development of extremely low background neutrino detectors and the progress on understanding neutrino propagation. We review the status and the prospects of the field

A journey through Earth climates

International Nuclear Information System (INIS)

Ramstein, Gilles; Brunet, Michel

2015-01-01

The author proposes a history of climates all along Earth's history, describes how cold and warm periods have been alternating during these billions of years. He also tries to highlight lessons learned from this long evolution of climate in order to better understand the current global warming. He discusses whether this disruption is unique in Earth's history, and how it threatens our environment and therefore our survival. The chapters describe how Earth could escape a global glaciation, the thermal regulation by greenhouse effect gases in a world without oxygen, the empowerment of oxygen and the first thermal accident, a new oxygenated and warm world, the second accident or how Earth entered and escaped from periods of total glaciation, the possible stabilisation, the succession of deregulations, crisis and extinctions, the slow way down to the cold, the various paleo-indicators during the Quaternary, the high frequency oscillations of climate during the last million of years, and the uncertain projections

Retention of fissure sealants using two different methods of application in teeth with hypomineralised molars (MIH): a 4 year clinical study.

Science.gov (United States)

Lygidakis, N A; Dimou, G; Stamataki, E

2009-12-01

This was to evaluate the retention rate of fissure sealants applied to MIH molars with occlusal enamel opacities, using two different application methods after 4 years. 54 children exhibiting molars with MIH aged 6-7 years, participated in the study. presence of at least 2 fully erupted caries-free maxillary or mandibular first permanent molars in the opposite sides of the mouth, both with occlusal enamel opacities without breakdown. Following parental consent, sealants were applied using a half-mouth experimental design. Group A: On a randomly assigned first molar on one side of the mouth sealants Fissurit were placed using a single bottle adhesive system (One-step prior to sealant application. Group B: Sealants were applied on the contra-lateral molar using the conventional etch and seal technique. Children were seen biannually when a preventive program was applied, without replacing any lost sealant. After 4 years, 47 sets of molars (94 teeth) were available for blind evaluation. Teeth in Group A presented a better retention rate; 70.2% were fully sealed, 29.7% partly sealed and none unsealed (lost sealant). Group B revealed 25.5% fully sealed, 44.6% partly sealed and 29.7% unsealed teeth. Differences between groups A and B were statistically significant (p0.01). In hypomineralised molars with occlusal opacities sealants appear to have greater retention when applied using 5th generation adhesive systems prior to sealant.

Process for lead removal from rare earth

International Nuclear Information System (INIS)

Bollat, A.; Sabot, J.L.

1987-01-01

An aqueous solution of rare earth chlorides and lead chlorides, with a chloride concentration of at least 2 moles/liter and a pH between 2 and 4, is extracted by an alkylphosphonic acid ester and rare earth(s) is (are) recovered from the organic phase [fr

Locating center of mass of earth and geostationary satellites

International Nuclear Information System (INIS)

Qureshi, A.; Marvi, M.

2014-01-01

CoM (Center of Mass) of earth is a very important factor which can play a major role in satellite communication and related earth sciences. The CoM of earth is assumed to be around equator due to geometrical shape of earth. However, no technical method is available in the literature which can justify the presence of CoM of earth around equator. Therefore, in this research work the CoM of earth has been located theoretically with the help of mathematical relations. It also presents the mathematical justification against the assumption that equator is the CoM of earth. The effect of calculated CoM of earth on geostationary satellites has also been discussed. The CoM of earth has been found mathematically by using land to ocean ratios and the data is collected from the Google earth software. The final results are accurate with an approximate error of 1%. (author)

The origin of the moon and the early history of the earth - a chemical model. Part 2: The earth

International Nuclear Information System (INIS)

O'Neill, H.St.C.

1991-01-01

The geochemical implications for the earth of a giant impact model for the origin of the earth-moon system are discussed, using a mass balance between three components: the proto-earth, the Impactor, and a late veneer. It is argued that the proto-earth accretes from material resembling a high temperature condensate from the solar nebula. Core formation takes place under very reducing conditions, resulting in the mantle of the proto-earth being completely stripped of all elements more siderophile than Fe, and partly depleted in the barely siderophile elements V, Cr, and perhaps Si. The Impactor then collides with the proto-earth, causing vaporisation of both the Impactor and a substantial portion of the earth's mantle. Most of this material recondenses to the earth, but some forms the moon. The Impactor adds most of the complement of the siderophile elements of the present mantle in an oxidized form. The oxidation state of the mantle is set near to its present, oxidized level. Finally, the addition of a late veneer, of composition similar to that of the H-group ordinary chondrites, accounts for the complement of the highly siderophile elements of the present mantle. The model accounts at least semi-quantitatively for the siderophile element abundances of the present mantle. Implications for the composition of the earth's core are discussed; the model predicts that neither S, O, nor Si should be present in sufficient quantities to provide the required light element in the core, whose identity, therefore, remains enigmatic

Contextualizing Earth Science Professional Development Courses for Geoscience Teachers in Boston: Earth Science II (Solid Earth)

Science.gov (United States)

Pringle, M. S.; Kamerer, B.; Vugrin, M.; Miller, M.

2009-12-01

Earth Science II: The Solid Earth -- Earth History and Planetary Science -- is the second of two Earth Science courses, and one of eleven graduate level science Contextualized Content Courses (CCC), that have been developed by the Boston Science Partnership as part of an NSF-funded Math Science Partnership program. A core goal of these courses is to provide high level science content to middle and high school teachers while modeling good instructional practices directly tied to the Boston Public Schools and Massachusetts science curriculum frameworks. All of these courses emphasize hands-on, lab-based, inquiry-driven, student-centered lessons. The Earth Science II team aimed to strictly adhere to ABC (Activity Before Concept) and 5E/7E models of instruction, and limited lecture or teacher-centered instruction to the later “Explanation” stages of all lessons. We also introduced McNeill and Krajick’s Claim-Evidence-Reasoning (CER) model of scientific explanation for middle school classroom discourse, both as a powerful scaffold leading to higher levels of accountable talk in the classroom, and to model science as a social construct. Daily evaluations, dutifully filled out by the course participants and diligently read by the course instructors, were quite useful in adapting instruction to the needs of the class on a real-time basis. We find the structure of the CCC teaching teams - university-based faculty providing expert content knowledge, K-12-based faculty providing age appropriate pedagogies and specific links to the K-12 curriculum - quite a fruitful, two-way collaboration. From the students’ perspective, one of the most useful takeaways from the university-based faculty was “listening to experts model out loud how they reason,” whereas some of the more practical takeaways (i.e., lesson components directly portable to the classroom?) came from the K-12-based faculty. The main takeaways from the course as a whole were the promise to bring more hands

Earth's earliest biosphere: Its origin and evolution

International Nuclear Information System (INIS)

Schopf, J.W.

1983-01-01

Some of the subjects discussed are related to the early biogeologic history, the nature of the earth prior to the oldest known rock record, the early earth and the Archean rock record, the prebiotic organic syntheses and the origin of life, Precambrian organic geochemistry, the biochemical evolution of anaerobic energy conversion, the isotopic inferences of ancient biochemistries, Archean stromatolites providing evidence of the earth's earliest benthos, Archean microfossils, the geologic evolution of the Archean-Early Proterozoic earth, and the environmental evolution of the Archean-Early Proterozoic earth. Other topics examined are concerned with geochemical evidence bearing on the origin of aerobiosis, biological and biochemical effects of the development of an aerobic environment, Early Proterozoic microfossils, the evolution of earth's earliest ecosystems, and geographic and geologic data for processed rock samples. Attention is given to a processing procedure for abiotic samples and calculation of model atmospheric compositions, and procedures of organic geochemical analysis

NASA'S Earth Science Data Stewardship Activities

Science.gov (United States)

Lowe, Dawn R.; Murphy, Kevin J.; Ramapriyan, Hampapuram

2015-01-01

NASA has been collecting Earth observation data for over 50 years using instruments on board satellites, aircraft and ground-based systems. With the inception of the Earth Observing System (EOS) Program in 1990, NASA established the Earth Science Data and Information System (ESDIS) Project and initiated development of the Earth Observing System Data and Information System (EOSDIS). A set of Distributed Active Archive Centers (DAACs) was established at locations based on science discipline expertise. Today, EOSDIS consists of 12 DAACs and 12 Science Investigator-led Processing Systems (SIPS), processing data from the EOS missions, as well as the Suomi National Polar Orbiting Partnership mission, and other satellite and airborne missions. The DAACs archive and distribute the vast majority of data from NASA’s Earth science missions, with data holdings exceeding 12 petabytes The data held by EOSDIS are available to all users consistent with NASA’s free and open data policy, which has been in effect since 1990. The EOSDIS archives consist of raw instrument data counts (level 0 data), as well as higher level standard products (e.g., geophysical parameters, products mapped to standard spatio-temporal grids, results of Earth system models using multi-instrument observations, and long time series of Earth System Data Records resulting from multiple satellite observations of a given type of phenomenon). EOSDIS data stewardship responsibilities include ensuring that the data and information content are reliable, of high quality, easily accessible, and usable for as long as they are considered to be of value.

Teaching and Learning about the Earth. ERIC Digest.

Science.gov (United States)

Lee, Hyonyong

This ERIC Digest investigates the earth and space science guidelines of the National Science Education Standards. These guidelines are frequently referred to as the earth system and include components such as plate tectonics, the water cycle, and the carbon cycle. This Digest describes the development of earth systems science and earth systems…

Educating the Public about Deep-Earth Science

Science.gov (United States)

Cronin, V. S.

2010-12-01

The nature of Earth’s interior is an active frontier of scientific research. Much of our current understanding of sub-crustal Earth is based on knowledge acquired in the last 2-3 decades, made possible by public funding and by dense seismic arrays, satellite remote sensing, increases in computer power that enable use of enhanced numerical techniques, improved theoretical and experimental knowledge of high PT mineral physics and chemistry, and a vigorous scientific community that has been trained to take advantage of these opportunities. An essential component of science is effective communication; therefore, providing for public education about science is a responsibility of the research community. Current public understanding of Earth’s interior is meager at best. In pre-college texts and in non-technical mass media, Earth's interior is typically visualized as an onion or baseball of concentric different-colored shells along whose upper surface "crustal" plates move like packages on conveyor belts of convecting mantle. Or the crust is thought to float on a molten mantle, as in the 19th century ideas of William Lowthian Green. Misconceptions about Earth that are brought to the undergraduate classroom must be confronted frankly and replaced by current understanding based on good science. Persistent ignorance has consequences. What do we want the public to know? First, the public should understand that knowledge of Earth's interior is important, not irrelevant. The public should know that deep-Earth processes result in Earth's dynamic magnetic field. Deep-Earth processes affect how radiation from the Sun reaches Earth, consequently affecting the atmosphere, the oceans, and the viability of life on Earth. The composition and differentiated structure of Earth's interior is a result of the early accretionary history of Earth and the Earth-Moon system. The public should also know that lithospheric tectonics, with all of its consequences (dynamic topography, volcanoes

Earth Observing System Covariance Realism Updates

Science.gov (United States)

Ojeda Romero, Juan A.; Miguel, Fred

2017-01-01

This presentation will be given at the International Earth Science Constellation Mission Operations Working Group meetings June 13-15, 2017 to discuss the Earth Observing System Covariance Realism updates.

Thermochemistry of rare-earth trifluorides

International Nuclear Information System (INIS)

Kim, K.Y.; Johnson, C.E.

1981-01-01

Using the most recent crystallographic data, the Born-Lande equation was employed to calculate lattice energies of the rare-earth trifluorides. The excellent agreement ( 0 sub(f)(MX 3 ,c,298.15K) can be estimated. The magnitude of the monotonic change of ΔH 0 sub(f)(MX 3 ) for the rare-earth trihalides series (14 4f electrons) is comparable to the energy change between Sc and Ti in which only one 3d electron is added. This energy change is consistent with the chemical evidence that the electrons in the f-orbitals of rare earths contribute negligibly to the bonding. (author)

Near-Earth Objects. Chapter 27

Science.gov (United States)

Harris, Alan W.; Drube, Line; McFadden, Lucy A.; Binzel, Richard P.

2014-01-01

A near-Earth object (NEO) is an asteroid or comet orbiting the Sun with a perihelion distance of less than 1.3 Astronomical Units (AU) (1 AU, an astronomical unit, is the mean distance between the Earth and the Sun, around 150 million kilometers). If the orbit of an NEO can bring it to within 0.05 AU of the Earth's orbit, and it is larger than about 120 meters, it is termed a potentially hazardous object (PHO); an object of this size is likely to survive passage through the atmosphere and cause extensive damage on impact. (The acronyms NEA and PHO are used when referring specifically to asteroids.)

In search of future earths: assessing the possibility of finding Earth analogues in the later stages of their habitable lifetimes.

Science.gov (United States)

O'Malley-James, Jack T; Greaves, Jane S; Raven, John A; Cockell, Charles S

2015-05-01

Earth will become uninhabitable within 2-3 Gyr as a result of the increasing luminosity of the Sun changing the boundaries of the habitable zone (HZ). Predictions about the future of habitable conditions on Earth include declining species diversity and habitat extent, ocean loss, and changes to geochemical cycles. Testing these predictions is difficult, but the discovery of a planet that is an analogue to future Earth could provide the means to test them. This planet would need to have an Earth-like biosphere history and to be approaching the inner edge of the HZ at present. Here, we assess the possibility of finding such a planet and discuss the benefits of analyzing older Earths. Finding an old-Earth analogue in nearby star systems would be ideal, because this would allow for atmospheric characterization. Hence, as an illustrative example, G stars within 10 pc of the Sun are assessed as potential old-Earth-analog hosts. Six of these represent good potential hosts. For each system, a hypothetical Earth analogue is placed at locations within the continuously habitable zone (CHZ) that would allow enough time for Earth-like biosphere development. Surface temperature evolution over the host star's main sequence lifetime (assessed by using a simple climate model) is used to determine whether the planet would be in the right stage of its late-habitable lifetime to exhibit detectable biosignatures. The best candidate, in terms of the chances of planet formation in the CHZ and of biosignature detection, is 61 Virginis. However, planet formation studies suggest that only a small fraction (0.36%) of G stars in the solar neighborhood could host an old-Earth analogue. If the development of Earth-like biospheres is rare, requiring a sequence of low-probability events to occur, biosphere evolution models suggest they are rarer still, with only thousands being present in the Galaxy as a whole.

Common Earth Science Misconceptions in Science Teaching

Science.gov (United States)

King, Chris

2012-01-01

A survey of the Earth science content of science textbooks found a wide range of misconceptions. These are discussed in this article with reference to the published literature on Earth science misconceptions. Most misconceptions occurred in the "sedimentary rocks and processes" and "Earth's structure and plate tectonics"…

New dynamic system suggested for earth expansion

Energy Technology Data Exchange (ETDEWEB)

Fitzpatrick, J [Asuncion Nacional Univ. (Paraguay). Inst. de Ciencias

1972-01-01

It is here suggested that there may have been much more radioactive materials in the deep interior of the earth than bitherto supposed. Trapped heat being generated in the interior would provide a mechanism for earth expansion. An assumption of heat generation in the deep interior of the earth of the order of 0,5 X 10-13 calories per second, per cubic centimeter, would provide sufficient thermal expansion to account for approximately 0.1 mm. change in the radius of the earth per year.

Big Earth Data Initiative: Metadata Improvement: Case Studies

Science.gov (United States)

Kozimor, John; Habermann, Ted; Farley, John

2016-01-01

Big Earth Data Initiative (BEDI) The Big Earth Data Initiative (BEDI) invests in standardizing and optimizing the collection, management and delivery of U.S. Government's civil Earth observation data to improve discovery, access use, and understanding of Earth observations by the broader user community. Complete and consistent standard metadata helps address all three goals.

RoboEarth: connecting robots worldwide

NARCIS (Netherlands)

Zweigle, O.; Molengraft, van de M.J.G.; D'Andrea, R.; Häussermann, K.

2009-01-01

In this paper, we present the core concept and the benefits of an approach called RoboEarth which will be highly beneficial for future robotic applications in science and industry. RoboEarth is a world-wide platform which robots can use to exchange position and map information as well as

Venus and the Archean Earth: Thermal considerations

International Nuclear Information System (INIS)

Sleep, N.H.

1989-01-01

The Archean Era of the Earth is not a direct analog of the present tectonics of Venus. In this regard, it is useful to review the state of the Archean Earth. Most significantly, the temperature of the adiabatic interior of the Earth was 200 to 300 C hotter than the current temperature. Preservation biases limit what can be learned from the Archean record. Archean oceanic crust, most of the planetary surface at any one time, has been nearly all subducted. More speculatively, the core of the Earth has probably cooled more slowly than the mantle. Thus the temperature contrast above the core-mantle boundary and the vigor of mantle plumes has increased with time on the Earth. The most obvious difference between Venus and the present Earth is the high surface temperature and hence a low effective viscosity of the lithosphere. In addition, the temperature contrast between the adiabatic interior and the surface, which drives convection, is less on Venus than on the Earth. It appears that the hot lithosphere enhanced tectonics on the early Venus significantly enough that its interior cooled faster than the Earth's. The best evidence for a cool interior of Venus comes from long wavelength gravity anomalies. The low interior temperatures retard seafloor spreading on Venus. The high surface temperatures on Venus enhance crustal deformation. That is, the lower crust may become ductile enough to permit significant flow between the upper crust and the mantle. There is thus some analogy to modern and ancient areas of high heat flow on the Earth. Archean crustal blocks typically remained stable for long intervals and thus overall are not good analogies to the deformation style on Venus

The ongoing educational anomaly of earth science placement

Science.gov (United States)

Messina, P.; Speranza, P.; Metzger, E.P.; Stoffer, P.

2003-01-01

The geosciences have traditionally been viewed with less "aCademic prTstige" than other science curricula. Among the results of this perception are depressed K-16 enrollments, Earth Science assignments to lower-performing students, and relegation of these classes to sometimes under-qualified educators, all of which serve to confirm the widely-held misconceptions. An Earth Systems course developed at San Jos??e State University demonstrates the difficulty of a standard high school Earth science curriculum, while recognizing the deficiencies in pre-college Earth science education. Restructuring pre-college science curricula so that Earth Science is placed as a capstone course would greatly improve student understanding of the geosciences, while development of Earth systems courses that infuse real-world and hands-on learning at the college level is critical to bridging the information gap for those with no prior exposure to the Earth sciences. Well-crafted workshops for pre-service and inservice teachers of Earth Science can heIp to reverse the trends and unfortunate "sTatus" in geoscience education.

EarthScope Education and Outreach: Accomplishments and Emerging Opportunities

Science.gov (United States)

Robinson, S.; Ellins, K. K.; Semken, S. C.; Arrowsmith, R.

2014-12-01

EarthScope's Education and Outreach (E&O) program aims to increase public awareness of Earth science and enhance geoscience education at the K-12 and college level. The program is distinctive among major geoscience programs in two ways. First, planning for education and public engagement occurred in tandem with planning for the science mission. Second, the NSF EarthScope program includes funding support for education and outreach. In this presentation, we highlight key examples of the program's accomplishments and identify emerging E&O opportunities. E&O efforts have been collaboratively led by the EarthScope National Office (ESNO), IRIS, UNAVCO, the EarthScope Education and Outreach Subcommittee (EEOSC) and PI-driven EarthScope projects. Efforts by the EEOSC, guided by an EarthScope Education and Outreach Implementation Plan that is periodically updated, focus EarthScope E&O. EarthScope demonstrated early success in engaging undergraduate students (and teachers) in its mission through their involvement in siting USArray across the contiguous U.S. Funded E&O programs such as TOTLE, Illinois EarthScope, CEETEP (for K-12), InTeGrate and GETSI (for undergraduates) foster use of freely available EarthScope data and research findings. The Next Generation Science Standards, which stress science and engineering practices, offer an opportunity for alignment with existing EarthScope K-12 educational resources, and the EEOSC recommends focusing efforts on this task. The EEOSC recognizes the rapidly growing use of mobile smart devices by the public and in formal classrooms, which bring new opportunities to connect with the public and students. This will capitalize on EarthScope's already prominent social media presence, an effort that developed to accomplish one of the primary goals of the EarthScope E&O Implementation Plan to "Create a high-profile public identity for EarthScope" and to "Promote science literacy and understanding of EarthScope among all audiences through

Enhanced pinning in mixed rare earth-123 films

Science.gov (United States)

Driscoll, Judith L [Los Alamos, NM; Foltyn, Stephen R [Los Alamos, NM

2009-06-16

An superconductive article and method of forming such an article is disclosed, the article including a substrate and a layer of a rare earth barium cuprate film upon the substrate, the rare earth barium cuprate film including two or more rare earth metals capable of yielding a superconductive composition where ion size variance between the two or more rare earth metals is characterized as greater than zero and less than about 10.times.10.sup.-4, and the rare earth barium cuprate film including two or more rare earth metals is further characterized as having an enhanced critical current density in comparison to a standard YBa.sub.2Cu.sub.3O.sub.y composition under identical testing conditions.

Thermodynamics of rare earths in steelmaking

International Nuclear Information System (INIS)

Vahed, A.; Kay, D.A.R.

1976-01-01

The standard free energies of formation of the oxides, sulfides and oxysulfides of cerium and lanthanum under steelmaking conditions have been calculated and used to predict the behavior of rare earths in steelmaking. Deoxidation and desulfurization constants, expressed in terms of Henrian activities, have been used to construct a precipitation diagram which indicates the sequence of rare earth inclusion formation. An enrichment of lanthanum in (RE)-oxysulfide and cerium in (RE)-sulfide is predicted. It is also predicted that rare earths should be able to reduce the soluble oxygen and sulfur contents of liquid steel well below the contents presently found in most industrial and laboratory practices. A simple method of calculating steelmaking additions for complete rare earth control of inclusion composition is presented

Volatile accretion history of the Earth.

Science.gov (United States)

Wood, B J; Halliday, A N; Rehkämper, M

2010-10-28

It has long been thought that the Earth had a protracted and complex history of volatile accretion and loss. Albarède paints a different picture, proposing that the Earth first formed as a dry planet which, like the Moon, was devoid of volatile constituents. He suggests that the Earth's complement of volatile elements was only established later, by the addition of a small veneer of volatile-rich material at ∼100 Myr (here and elsewhere, ages are relative to the origin of the Solar System). Here we argue that the Earth's mass balance of moderately volatile elements is inconsistent with Albarède's hypothesis but is well explained by the standard model of accretion from partially volatile-depleted material, accompanied by core formation.

Smarter Earth Science Data System

Science.gov (United States)

Huang, Thomas

2013-01-01

The explosive growth in Earth observational data in the recent decade demands a better method of interoperability across heterogeneous systems. The Earth science data system community has mastered the art in storing large volume of observational data, but it is still unclear how this traditional method scale over time as we are entering the age of Big Data. Indexed search solutions such as Apache Solr (Smiley and Pugh, 2011) provides fast, scalable search via keyword or phases without any reasoning or inference. The modern search solutions such as Googles Knowledge Graph (Singhal, 2012) and Microsoft Bing, all utilize semantic reasoning to improve its accuracy in searches. The Earth science user community is demanding for an intelligent solution to help them finding the right data for their researches. The Ontological System for Context Artifacts and Resources (OSCAR) (Huang et al., 2012), was created in response to the DARPA Adaptive Vehicle Make (AVM) programs need for an intelligent context models management system to empower its terrain simulation subsystem. The core component of OSCAR is the Environmental Context Ontology (ECO) is built using the Semantic Web for Earth and Environmental Terminology (SWEET) (Raskin and Pan, 2005). This paper presents the current data archival methodology within a NASA Earth science data centers and discuss using semantic web to improve the way we capture and serve data to our users.

The Sun-earth Imbalance radiometer for a direct measurement of the net heating of the earth

Science.gov (United States)

Dewitte, Steven; Karatekin, Özgür; Chevalier, Andre; Clerbaux, Nicolas; Meftah, Mustapha; Irbah, Abdanour; Delabie, Tjorven

2015-04-01

It is accepted that the climate on earth is changing due to a radiative energy imbalance at the top of the atmosphere, up to now this radiation imbalance has not been measured directly. The measurement is challenging both in terms of space-time sampling of the radiative energy that is leaving the earth and in terms of accuracy. The incoming solar radiation and the outgoing terrestrial radiation are of nearly equal magnitude - of the order of 340 W/m² - resulting in a much smaller difference or imbalance of the order of 1 W/m². The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar and the outgoing terrestrial radiation with the same instrument. Based on our 30 year experience of measuring the Total Solar Irradiance with the Differential Absolute RADiometer (DIARAD) type of instrument and on our 10 year experience of measuring the Earth Radiation Budget with the Geostationary Earth Radiation Budget (GERB) instrument on Meteosat Second Generation, we propose an innovative constellation of Sun-earth IMBAlance (SIMBA) radiometer cubesats with the ultimate goal to measure the Sun-earth radiation imbalance. A first Simba In Orbit Demonstration satellite is scheduled for flight with QB50 in 2015. It is currently being developed as ESA's first cubesat through an ESA GSTP project. In this paper we will give an overview of the Simba science objectives and of the current satellite and payload development status.

A rocky composition for an Earth-sized exoplanet.

Science.gov (United States)

Howard, Andrew W; Sanchis-Ojeda, Roberto; Marcy, Geoffrey W; Johnson, John Asher; Winn, Joshua N; Isaacson, Howard; Fischer, Debra A; Fulton, Benjamin J; Sinukoff, Evan; Fortney, Jonathan J

2013-11-21

Planets with sizes between that of Earth (with radius R Earth symbol) and Neptune (about 4R Earth symbol) are now known to be common around Sun-like stars. Most such planets have been discovered through the transit technique, by which the planet's size can be determined from the fraction of starlight blocked by the planet as it passes in front of its star. Measuring the planet's mass--and hence its density, which is a clue to its composition--is more difficult. Planets of size 2-4R Earth symbol have proved to have a wide range of densities, implying a diversity of compositions, but these measurements did not extend to planets as small as Earth. Here we report Doppler spectroscopic measurements of the mass of the Earth-sized planet Kepler-78b, which orbits its host star every 8.5 hours (ref. 6). Given a radius of 1.20 ± 0.09 R Earth symbol and a mass of 1.69 ± 0.41 R Earth symbol, the planet's mean density of 5.3 ± 1.8 g cm(-3) is similar to Earth's, suggesting a composition of rock and iron.

Cosmology and the expanding Earth hypothesis

International Nuclear Information System (INIS)

Tryon, E.P.

1983-01-01

The standard model of cosmology is briefly presented, together with a recent conjecture that the initial matter in the universe might have been spontaneously created from nothing as a result of relativistic quantum physics. The possibility of Earth expansion from a continuing creation of matter is then considered. A critique is presented of efforts to relate Earth expansion to the Hubble expansion of the universe. Possible changes in Earth radius as a result of diminishing gravity are also discussed

Venus tectonics: another Earth or another Mars

International Nuclear Information System (INIS)

McGill, G.E.

1979-01-01

The presence of presumably primordial large craters has led to the suggestion that Venus may have a thick lithosphere like that of Mars despite its similarities to Earth in size and density. However, crust and upper mantle temperatures on Venus are very likely higher than on Earth so that a dry Venus could have a lithosphere with a thickness similar to that of Earth. If a trace of volatiles is present in the mantle, the lithosphere of Venus could be thinner. Due to the absence of liquid water, erosion and deposition will be much slower on Venus than on Earth, favoring retention of primordial cratered surfaces on portions of the crust that have not been destroyed or buried by tectonic and volcanic activity. Geochemical models of solar system origin and petrological considerations suggest that K is about as abundant in Venus as in Earth. The abundance of 40 Ar in the atmosphere of Venus lies somewhere between the Earth value and one-tenth of the Earth value. Because erosional liberation of 40 Ar on Venus will be relatively inefficient, this range for 40 Ar abundance at least permits an active tectonic history, and if the 40 Ar abundance is towards the high end of the range, it may well require an active tectonic history. Thus we are not constrained to a Mars-like model of Venus tectonics by craters and possible mantle dryness; an Earth-like model is equally probable

Theory of Rare-Earth Alloys

DEFF Research Database (Denmark)

Lindgård, Per-Anker

1977-01-01

A mean-field random alloy theory combined with a simple calculation of the exchange interaction J(c,Q) is shown to quantitatively account for the phase diagrams for alloys of rare-earth metals with Y, Lu, Sc, and other rare-earth metals. A concentration-dependent J(c,Q) explains the empirical 2...

Age of the earth and solar system

International Nuclear Information System (INIS)

Manhes, G.

1977-01-01

The history of chemical element formation and radiochronology is given. The study of Pb isotope composition evolution enables to estimate the age of the earth. A series of galena of known ages was measured. By means of a model, it is possible to determine the initial isotope composition of Pb on the earth and the age of the earth. On the other hand, the analysis of stony meteorites provides a Pb isotope composition higher than the earth value. A comparison of the data shows a fundamental transition at 4.55 10 9 years [fr

Processing of monazite at the rare earth division,Udyogamandal

International Nuclear Information System (INIS)

Narayanan, N.S.; Thulasidoss, S.; Ramachandran, T.V.; Swaminathan, T.V.; Prasad, K.R.

1988-01-01

The processing techniques adopted at the Rare Earth Division of the Indian Rare Earths Limited at Udyogamandal, for the production of rare earth compounds of various compositions and purity grades are reviewed. Over 100 different compounds are produced and marketed, and these include mixed rare earths chloride, crude thorium concentrate, cerium oxide, cerium hydrate, rare earths carbonate, didymium salts and individual rare earth oxides and salts. Also, the trisodium phosphate obtained as byproduct in the processing of monazite, is recovered and marketed. The process scheme for monazite essentially involves alkaline digestion of ground monazite, removal of the by-product trisodium phosphate, separation of thorium through preferential dissolution of rare earths hydroxide in hydrochloric acid under controlled pH and temperature conditions followed by purification, and evaporation of the chloride solution to yield pure rare earths chloride. Part of the chloride is utilised for the production of individual rare earth compounds after separation by solvent extraction and ion exchange processes. Individual rare earth compounds of 99.99 %+ purity are regularly produced to cater to the demand within the country. (author) 8 figs., 1 tab

The population of natural Earth satellites

Science.gov (United States)

Granvik, Mikael; Vaubaillon, Jeremie; Jedicke, Robert

2012-03-01

We have for the first time calculated the population characteristics of the Earth’s irregular natural satellites (NESs) that are temporarily captured from the near-Earth-object (NEO) population. The steady-state NES size-frequency and residence-time distributions were determined under the dynamical influence of all the massive bodies in the Solar System (but mainly the Sun, Earth, and Moon) for NEOs of negligible mass. To this end, we compute the NES capture probability from the NEO population as a function of the latter’s heliocentric orbital elements and combine those results with the current best estimates for the NEO size-frequency and orbital distribution. At any given time there should be at least one NES of 1-m diameter orbiting the Earth. The average temporarily-captured orbiter (TCO; an object that makes at least one revolution around the Earth in a co-rotating coordinate system) completes (2.88 ± 0.82) rev around the Earth during a capture event that lasts (286 ± 18) d. We find a small preference for capture events starting in either January or July. Our results are consistent with the single known natural TCO, 2006 RH120, a few-meter diameter object that was captured for about a year starting in June 2006. We estimate that about 0.1% of all meteors impacting the Earth were TCOs.