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Sample records for littoral cell angioma

  1. Littoral cell angioma: A case report

    PubMed Central

    Bailey, Amanda; Vos, Jeffrey; Cardinal, Jon

    2015-01-01

    Primary splenic lesions are rare entities among which littoral cell angioma (LCA) is a recently described, uncommon vascular lesion that is unique to the spleen. It has heretofore been described primarily in pathologic series and has been found mostly to behave as a benign entity. A few reports of malignant variants have been reported. We present a case report of a solitary LCA discovered after splenectomy for an incidentally discovered splenic lesion, along with a literature review. PMID:26488026

  2. The splenic Littoral cell angioma in China: a case report and review.

    PubMed

    Hu, Zong-Qiang; A, Yong-Jun; Sun, Qiang-Ming; Li, Wen; Li, Li

    2011-01-01

    Littoral cell angioma (LCA) is a rare splenic vascular neoplasm that arises from the cells lining the red pulp sinuses. It is deemed to be a benign and incidental lesion. The earliest literature report of littoral cell angioma has been described by Falk. The examination of samples after splenectomy reveals similar pathological change and its change rule is summarized. However, many recent reports have described it to be a malignant tumor with congenital and immunological associations. Generally speaking, the definitive diagnosis can only be made after histological and immunohistochemical profiles. In this case report, we presented the case of a 48-year-old woman with multiple splenic LCAs. Initially, the patient was characteristics of abdominal distension, weakness and fatigue. Multiple hemangiomas were observed in the spleen through abdominal ultrasonic diagnosis. Computed tomography (CT) scans revealed the splenomegaly with multiple round and hyperdense lesions. The patient subsequently underwent splenectomy. Postoperative histological and immunohistochemical studies confirmed the diagnosis of LCA. Based on the presentation of this case, clinical, radiographic and pathological results of LCA as well as recent advances in our understanding of this uncommon splenic lesion were reviewed. LCA is an uncommon splenic tumor diagnosed in patients with or without abdominal discomfort. Only a few case reports regarding this kind of tumor have been published as inconsistent results. In the present paper, we have reported a case of LCA and reviewed the literature. PMID:22172167

  3. Laparoscopic splenectomy for a littoral cell angioma of the spleen: Case report.

    PubMed

    Marzetti, Alice; Messina, Federico; Prando, Daniela; Verza, Luca A; Vacca, Ugo; Azabdaftari, Alireza; Rubinato, Leonardo; Reale, Domenico; Favat, Massimo; Barbujani, Mario; Agresta, Ferdinando

    2015-11-16

    A littoral cell angioma (LCA) is a primary vascular tumor of the spleen, that can have malignant potential and may present association with other malignancies. This is a case of LCA that was discovered incidentally in a 79-year-old woman who presented with a polycythemia at the time of consultation. The neoplasm was evaluated by ultrasound and computed tomography. The patient underwent a splenectomy that revealed LCA by pathological evaluation. The post-operative outcome was favorable with no complications or recurrent disease. This case presentation, clinical, radiographic, and pathological features of an uncommon splenic tumor can be studied in order to advance our knowledge in our understanding of LCA. PMID:26601099

  4. Laparoscopic splenectomy for a littoral cell angioma of the spleen: Case report

    PubMed Central

    Marzetti, Alice; Messina, Federico; Prando, Daniela; Verza, Luca A; Vacca, Ugo; Azabdaftari, Alireza; Rubinato, Leonardo; Reale, Domenico; Favat, Massimo; Barbujani, Mario; Agresta, Ferdinando

    2015-01-01

    A littoral cell angioma (LCA) is a primary vascular tumor of the spleen, that can have malignant potential and may present association with other malignancies. This is a case of LCA that was discovered incidentally in a 79-year-old woman who presented with a polycythemia at the time of consultation. The neoplasm was evaluated by ultrasound and computed tomography. The patient underwent a splenectomy that revealed LCA by pathological evaluation. The post-operative outcome was favorable with no complications or recurrent disease. This case presentation, clinical, radiographic, and pathological features of an uncommon splenic tumor can be studied in order to advance our knowledge in our understanding of LCA. PMID:26601099

  5. Littoral cell angioma presenting as metastatic thyroid carcinoma to the spleen.

    PubMed

    Mohan, Vineeth; Jones, Ralph C; Drake, Almond J; Daly, Patrick L; Shakir, K M Mohamed

    2005-02-01

    Papillary thyroid carcinoma (PTC) commonly metastasizes to cervical lymph nodes. Distant metastases are unusual with the lungs most frequently involved. Well-differentiated thyroid carcinoma very rarely presents with metastases to the spleen. This is the case of a 25-year-old man with a history of PTC (1.4 cm primary; no capsular invasion and negative lymph node metastases). One year after initial surgery, recurrent disease was found in multiple neck nodes by central neck dissection. Whole body scan (WBS) following a therapeutic ablation dose of 150 mCi I(131) revealed mediastinal metastases. Computerized axial tomography (CT) of the chest one year later showed no gross mediastinal or pulmonary disease. However, multiple large splenic lesions were incidentally noted. Evaluation by ultrasound (US) showed lesions to be solid echogenic masses without remarkable Doppler characteristics to suggest vascular tumors. US-guided percutaneous fine-needle aspiration biopsy (FNAB) of one lesion was nondiagnostic. After withdrawal from Levothyroxine, serum TSH was >100 mU/L with a thyroglobulin of 9.4 ng/mL and negative anti-thyroglobulin antibodies. Diagnostic WBS revealed faint splenic uptake but was otherwise unremarkable. Following treatment with 192 mCi I(131), WBS demonstrated increased activity in the mediastinum as well as in the spleen suggesting mediastinal and splenic metastases. Contrast CT of the abdomen showed multiple low-attenuated heterogeneously enhancing splenic masses, normal liver and no intra-abdominal lymphadenopathy. The largest mass (4.5 x 3.5 cm) was exophytic and in close proximity to the splenic capsule. Despite the serum thyroglobulin of only 9.4 ng/mL, the finding of I(131) accumulation within solid splenic masses led to a preoperative diagnosis of thyroid carcinoma metastases. To establish the diagnosis and to remove the risk for splenic rupture, a laparoscopic splenectomy was performed. Histopathologic analysis showed large littoral cell angiomas

  6. Angioma Alliance

    MedlinePlus

    ... Research Shop to Support Us Our Videos Angioma Alliance Night at the Cincinnati Reds Cavernous Angioma and Children Dr. Issam Awad at the Angioma Alliance Family Conference info@AngiomaAlliance.org | © Angioma Alliance | Disclaimer | ...

  7. Littoral cell angiosarcoma in a dog.

    PubMed

    Gal, A; Yamate, J; Golbar, H M; Spoerer, K; Fredrickson, R

    2013-01-01

    This report describes the microscopical and immunohistochemical characteristics of littoral cell angiosarcoma in a 12-year-old, neutered female, beagle dog. The dog succumbed to metastatic disease 3 months after diagnosis of a mid-splenic mass. The tumour was characterized by two histological patterns: anastomosing microvascular channels and microvascular papillary fronds. The neoplastic cells expressed both endothelial and histiocytic markers and were erythrophagocytic. Immunohistochemical findings consistent with malignancy were CD34 expression and high Ki67 nuclear immunoreactivity. PMID:23453493

  8. About Cavernous Angioma

    MedlinePlus

    ... and School CCM3 Mutation Resources Our Videos Angioma Alliance Night at the Cincinnati Reds Cavernous Angioma and Children Dr. Issam Awad at the Angioma Alliance Family Conference info@AngiomaAlliance.org | © Angioma Alliance | Disclaimer | ...

  9. Littoral transport rates in the Santa Barbara Littoral Cell: a process-based model analysis

    USGS Publications Warehouse

    Elias, E. P. L.; Barnard, Patrick L.; Brocatus, John

    2009-01-01

    Identification of the sediment transport patterns and pathways is essential for sustainable coastal zone management of the heavily modified coastline of Santa Barbara and Ventura County (California, USA). A process-based model application, based on Delft3D Online Morphology, is used to investigate the littoral transport potential along the Santa Barbara Littoral Cell (between Point Conception and Mugu Canyon). An advanced optimalization procedure is applied to enable annual sediment transport computations by reducing the ocean wave climate in 10 wave height - direction classes. Modeled littoral transport rates compare well with observed dredging volumes, and erosion or sedimentation hotspots coincide with the modeled divergence and convergence of the transport gradients. Sediment transport rates are strongly dependent on the alongshore variation in wave height due to wave sheltering, diffraction and focusing by the Northern Channel Islands, and the local orientation of the geologically-controlled coastline. Local transport gradients exceed the net eastward littoral transport, and are considered a primary driver for hot-spot erosion.

  10. Cerebral venous angiomas

    SciTech Connect

    Olson, E.; Gilmor, R.L.; Richmond, B.

    1984-04-01

    Several unusual cases of cerebral venous angiomas as well as some characteristic cases are reported. The characteristic angiographic feature is that of a collection of dilated medullary veins draining into a single large draining vein, which appears first in the early venous phase and persists into the late venous phase of the arteriogram. Computed tomography (CT) was abnormal in 12/13 cases. The draining vein was the most common abnormality identified on CT. Coronal and sagittal reconstruction may be helpful in demonstrating the draining vein. A case of large twin venous angiomas, a case of hemorrhage from a venous angioma, and a case of a venous angioma with an incidentally associated glioblastoma are presented.

  11. Classification of rocky headlands in California with relevance to littoral cell boundary delineation

    USGS Publications Warehouse

    George, David L.; Largier, JL; Storlazzi, Curt; Barnard, Patrick

    2015-01-01

    Despite extensive studies of hydrodynamics and sediment flux along beaches, there is little information on the processes, pathways and timing of water and sediment transport around rocky headlands. In this study, headlands along the California coast are classified to advance understanding of headland dynamics and littoral cell boundaries in support of improved coastal management decisions. Geomorphological parameters for 78 headlands were quantified from geological maps, remote-sensing imagery, navigational charts, and shoreline geospatial databases. K-means cluster analysis grouped the headlands into eight distinct classes based on headland perimeter, bathymetric slope ratio, and the headland apex angle. Wave data were used to investigate the potential for sediment transport around the headland types and determine the efficacy of the headland as a littoral cell boundary. Four classes of headland appear to function well as littoral cell boundaries, with headland size (e.g., perimeter or area) and a marked change in nearshore bathymetry across the headland being relevant attributes. About half of the traditional California littoral cell boundaries align with headland classes that are expected to perform poorly in blocking alongshore sediment transport, calling into question these boundaries. Better definition of these littoral cell boundaries is important for regional sediment management decisions.

  12. Regional Sediment Budget of the Columbia River Littoral Cell, USA

    USGS Publications Warehouse

    Buijsman, Maarten C.; Sherwood, C.R.; Gibbs, A.E.; Gelfenbaum, G.; Kaminsky, G.M.; Ruggiero, P.; Franklin, J.

    2002-01-01

    Summary -- In this Open-File Report we present calculations of changes in bathymetric and topographic volumes for the Grays Harbor, Willapa Bay, and Columbia River entrances and the adjacent coasts of North Beach, Grayland Plains, Long Beach, and Clatsop Plains for four intervals: pre-jetty - 1920s (Interval 1), 1920s - 1950s (Interval 2), 1950s - 1990s (Interval 3), and 1920s 1990s (Interval 4). This analysis is part of the Southwest Washington Coastal Erosion Study (SWCES), the goals of which are to understand and predict the morphologic behavior of the Columbia River littoral cell on a management scale of tens of kilometers and decades. We obtain topographic Light Detection and Ranging (LIDAR) data from a joint project by the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), National Aeronautic and Space Administration (NASA), and the Washington State Department of Ecology (DOE) and bathymetric data from the U.S. Coast and Geodetic Survey (USC&GS), U.S. Army Corps of Engineers (USACE), USGS, and the DOE. Shoreline data are digitized from T-Sheets and aerial photographs from the USC&GS and National Ocean Service (NOS). Instead of uncritically adjusting each survey to NAVD88, a common vertical land-based datum, we adjust some surveys to produce optimal results according to the following criteria. First, we minimize offsets in overlapping surveys within the same era, and second, we minimize bathymetric changes (relative to the 1990s) in deep water, where we assume minimal change has taken place. We grid bathymetric and topographic datasets using kriging and triangulation algorithms, calculate bathymetric-change surfaces for each interval, and calculate volume changes within polygons that are overlaid on the bathymetric-change surfaces. We find similar morphologic changes near the entrances to Grays Harbor and the Columbia River following jetty construction between 1898 and 1916 at the Grays Harbor entrance and between 1885 and

  13. Beach morphology monitoring in the Elwha River Littoral Cell, 2004-2009

    USGS Publications Warehouse

    Warrick, Jonathon A.; George, Douglas A.; Stevens, Andrew W.; Eshleman, Jodi; Gelfenbaum, Guy; Kaminsky, George M.; Schwartz, Andrew K.; Bierne, Matt

    2007-01-01

    This report describes the methods used, data collected, and results of the Beach Morphology Monitoring Program in the Elwha River Littoral Cell, starting in 2004. The U.S. Geological Survey and the Washington State Department of Ecology collaborated in the data collection with the support of the local Lower Elwha Klallam Tribe. Beach monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data by using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). The monitoring program was designed to characterize the littoral system of the Elwha River before the scheduled removal of two large dams in 2012. A primary objective of this work is to quantitatively describe the topography and bathymetry of the Elwha River littoral system so that the effects of dam removal may be quantified. Sediment inputs following dam removal are hypothesized to result in (A) larger amounts of fine sediment grain-sizes entering the littoral system and, (B) a reduction or reversal of coastal erosion.

  14. A rapid compatibility analysis of potential offshore sand sources for beaches of the Santa Barbara Littoral Cell

    USGS Publications Warehouse

    Mustain, N.; Griggs, G.; Barnard, P.L.

    2007-01-01

    The beaches of the Santa Barbara Littoral Cell, which are narrow as a result of either natural and/or anthropogenic factors, may benefit from nourishment. Sand compatibility is fundamental to beach nourishment success and grain size is the parameter often used to evaluate equivalence. Only after understanding which sand sizes naturally compose beaches in a specific cell, especially the smallest size that remains on the beach, can the potential compatibility of source areas, such as offshore borrow sites, be accurately assessed. This study examines sediments on the beach and in the nearshore (5-20m depth) for the entire Santa Barbara Littoral Cell east of Point Conception. A digital bed sediment camera, the Eyeball??, and spatial autocorrelation technique were used to determine sediment grain size. Here we report on whether nearshore sediments are comparable and compatible with beach sands of the Santa Barbara Littoral Cell. ?? 2007 ASCE.

  15. Seasonal to interannual morphodynamics along a high-energy dissipative littoral cell

    USGS Publications Warehouse

    Ruggiero, P.; Kaminsky, G.M.; Gelfenbaum, G.; Voigt, B.

    2005-01-01

    A beach morphology monitoring program was initiated during summer 1997 along the Columbia River littoral cell (CRLC) on the coasts of northwest Oregon and southwest Washington, USA. This field program documents the seasonal through interannual morphological variability of these high-energy dissipative beaches over a variety of spatial scales. Following the installation of a dense network of geodetic control monuments, a nested sampling scheme consisting of cross-shore topographic beach profiles, three-dimensional topographic beach surface maps, nearshore bathymetric surveys, and sediment size distribution analyses was initiated. Beach monitoring is being conducted with state-of-the-art real-time kinematic differential global positioning system survey methods that combine both high accuracy and speed of measurement. Sampling methods resolve variability in beach morphology at alongshore length scales of approximately 10 meters to approximately 100 kilometers and cross-shore length scales of approximately 1 meter to approximately 2 kilometers. During the winter of 1997/1998, coastal change in the US Pacific Northwest was greatly influenced by one of the strongest El Nin??o events on record. Steeper than typical southerly wave angles resulted in alongshore sediment transport gradients and shoreline reorientation on a regional scale. The La Nin??a of 1998/1999, dominated by cross-shore processes associated with the largest recorded wave year in the region, resulted in net beach erosion along much of the littoral cell. The monitoring program successfully documented the morphological response to these interannual forcing anomalies as well as the subsequent beach recovery associated with three consecutive moderate wave years. These morphological observations within the CRLC can be generalized to explain overall system patterns; however, distinct differences in large-scale coastal behavior (e.g., foredune ridge morphology, sandbar morphometrics, and nearshore beach slopes

  16. An application of LIDAR to analyses of El Nino erosion in the Netarts littoral cell, Oregon

    USGS Publications Warehouse

    Revell, D.L.; Komar, P.D.; Sallenger, A.H., Jr.

    2002-01-01

    El Nin??o produces coastal and beach erosion along the West Coast of the USA by elevating mean water levels so that tides are significantly higher than predicted, and by altering the paths of storms that generate large waves. In the past it has been difficult to adequately document the erosion impacts since they are so widespread. This difficulty has been solved through the application of LIDAR, which uses a scanning laser mounted in a small aircraft to rapidly and accurately survey beach elevations. This study uses LIDAR to document the beach changes and shoreline erosion that occurred during the 1997-98 El Nin??o within the Netarts Littoral Cell on the Oregon coast, a 14-km long "pocket beach" between large rocky headlands. The LIDAR surveys demonstrate that sand generally migrated northward within the cell due to the southwest approach of the El Nin??o storm waves, but there was a complex pattern of beach-elevation change due to the superposition of eroded rip-current embayments. The greatest beach erosion occurred near the south end of the cell, where it impacted Cape Lookout State Park, and to the north of the inlet to Netarts Bay where it threatened The Capes, a development of condominiums located on a high bluff. In both cases the LIDAR data proved to be extremely useful in quantifying the erosion, and in providing a better understanding of the erosion processes that occur during an El Nin??o.

  17. Beach morphology monitoring in the Columbia River Littoral Cell: 1997-2005

    USGS Publications Warehouse

    Ruggiero, Peter; Eshleman, Jodi L.; Kingsley, Etienne; Thompson, David M.; Voigt, Brian; Kaminsky, George M.; Gelfenbaum, Guy

    2007-01-01

    This report describes methods used, data collected, and results of the Beach Morphology Monitoring Program in the Columbia River Littoral Cell (CRLC) from 1997 to 2005. A collaborative group primarily consisting of the US Geological Survey and the Washington State Department of Ecology performed this work. Beach Monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). Sediment size distribution data was also collected as part of this effort. The monitoring program was designed to: 1) quantify the short- to medium-term (seasonal to interannual) beach change rates and morphological variability along the CRLC and assess the processes responsible for these changes; 2) collect beach state data (i.e., grain size, beach slope, and dune/sandbar height/position) to enhance the conceptual understanding of CRLC functioning and refine predictions of future coastal change and hazards; 3) compare and contrast the scales of environmental forcing and beach morphodynamics in the CRLC to other coastlines of the world; and 4) provide beach change data in a useful format to land use managers.

  18. Dermoscopy of acral angioma serpiginosum.

    PubMed

    Freites-Martinez, Azael; Martinez-Sanchez, Diego; Tardío, Juan Carlos; Huerta-Brogeras, Maria; Borbujo, Jesús

    2015-02-01

    Angioma serpiginosum (AS) is an unusual vascular disorder that typically affects female patients, begins in childhood and stabilizes in adulthood and not frequently involve acral skin. We herein present a 13 year-old girl with an asymptomatic erythematous punctuate first noticed on the right palm three years ago, with a proximal serpiginous progression up to the forearm. On examination there was a nonblanching erythematous punctuate on the palm and the inner aspect of right hand and forearm. Dermoscopy showed an erythematous parallel ridge pattern with some red globules and dots spreading on a linear arrangement, and the acrosyringia openings were not affected. Histopathological study showed dilated capillaries in the dermal papillae. This feature is consistent with angioma serpiginosum (AS). To the best of our knowledge, this is the first report that shows a dermoscopic image of a palmar AS. The dermoscopic pattern described in this case could aid in the diagnosis of AS and could add a value in the differential diagnosis with vascular lesions on acral skin. PMID:25756486

  19. Cavernous angioma of the pineal region.

    PubMed

    Donati, P; Maiuri, F; Gangemi, M; Gallicchio, B; Sigona, L

    1992-01-01

    The pineal region is one of the most rare localizations of intracranial cavernous angiomas, with only 8 cases reported up today. The Authors report a case of cavernous angioma of such localization and review the pertinent literature. Magnetic resonance allows the correct diagnosis of cavernous malformations on the basis of their typical aspect, even in the absence of histological verification. We suggest that this imaging technique will allow to identify more frequently pineal cavernomas preoperatively, thus avoiding useless irradiation. PMID:1484302

  20. An integrated approach to coastal erosion problems in northern Tuscany (Italy): Littoral morphological evolution and cell distribution

    NASA Astrophysics Data System (ADS)

    Anfuso, G.; Pranzini, E.; Vitale, G.

    2011-06-01

    Occupation of the coast has significantly increased in recent decades, mostly due to a greater demand for recreation and tourism. Today, erosion threatens many human-made structures and activities, requiring an integrated approach for the understanding of coastal dynamics and identification of alternatives to associated problems. This study investigates a 64 km-long coastal physiographic unit in the northern microtidal littoral of Tuscany (Italy). Vertical aerial photographs and direct field surveys were used to retrieve changes in shoreline position over 1938-1997 and 1997-2005 time intervals. Significant beach accretion was observed during the first period updrift of Carrara (84 m) and Viareggio (280 m) harbours and at Marina di Pietrasanta (100 m), whereas severe erosion occurred downcoast of Carrara harbour (- 130 m, at Marina dei Ronchi) and on the northern side of Arno river mouth (- 400 m). Similar trends were observed between 1997 and 2005; beach slope between the 1997 shoreline position and the closure depth correlated well with the distribution of erosion/accretion patterns from the 1938-1997 period (slopes were lower in eroded areas than at sites under accretion). Longshore distribution of erosion/accretion patterns was controlled by coastal compartmentalisation. Three of the main littoral cells were mostly formed by natural limits (i.e., Punta Bianca promontory, Marina di Pietrasanta, the Arno river mouth and the port of Livorno). Several sub-cells were created within these cells due to the introduction of human-made structures (such as Carrara and Viareggio harbours), which formed artificial fixed limits that allowed the transport of sediments (exclusively fines) in one direction only. Results will help improve the understanding of coastal processes and manage littoral sediment transport in a sustainable manner. This will reduce the need for structural interventions, such as breakwaters and groynes, which in the past decades prevented coastal retreat

  1. Beach response dynamics of a littoral cell using a 17-year single-point time series of sand thickness

    USGS Publications Warehouse

    Barnard, P.L.; Hubbard, D.M.; Dugan, J.E.

    2012-01-01

    A 17-year time series of near-daily sand thickness measurements at a single intertidal location was compared with 5. years of semi-annual 3-dimensional beach surveys at the same beach, and at two other beaches within the same littoral cell. The daily single point measurements correlated extremely well with the mean beach elevation and shoreline position of ten high-spatial resolution beach surveys. Correlations were statistically significant at all spatial scales, even for beach surveys 10s of kilometers downcoast, and therefore variability at the single point monitoring site was representative of regional coastal behavior, allowing us to examine nearly two decades of continuous coastal evolution. The annual cycle of beach oscillations dominated the signal, typical of this region, with additional, less intense spectral peaks associated with seasonal wave energy fluctuations (~. 45 to 90. days), as well as full lunar (~. 29. days) and semi-lunar (~. 13. days; spring-neap cycle) tidal cycles. Sand thickness variability was statistically linked to wave energy with a 2. month peak lag, as well as the average of the previous 7-8. months of wave energy. Longer term anomalies in sand thickness were also apparent on time scales up to 15. months. Our analyses suggest that spatially-limited morphological data sets can be extremely valuable (with robust validation) for understanding the details of beach response to wave energy over timescales that are not resolved by typical survey intervals, as well as the regional behavior of coastal systems. ?? 2011.

  2. A case of acquired tufted angioma in adulthood.

    PubMed

    Pesapane, Filippo; Nazzaro, Gianluca; Alberti-Violetti, Silvia; Gianotti, Raffaele

    2015-01-01

    Tufted angioma is a rare vascular tumor whose name derives from its histopathological appearance, characterized by tufts of capillaries within the dermis. Its etiology and pathogenesis are uncertain. Tufted angioma typically occurs during infancy or early childhood and displays various clinical patterns. It may present as a subtle stain-like area that later thickens as a large plaque, infiltrated or dusky blue-purple lesion, or as an exophytic, firm, violaceous, cutaneous nodule. Medical treatment is not necessary for tufted angioma, given its benign nature and slow progression. Only clinical follow-up is therefore recommended. PMID:26312663

  3. An acquired tufted angioma of the nasal cavity.

    PubMed

    Kim, Young Ha; Lee, Guen-Ho; Lee, Su Hyun; Cho, Jin Hee

    2013-12-01

    Tufted angiomas are benign vascular tumors that occur mainly in children younger than 5 years, involving the skin with subcutaneous plaques or in a nodular form. We experienced a rare tufted angioma in the nasal cavity. A 35-year-old woman visited our clinic because of frequent epistaxis. A mass was found in the left posterior nasal cavity, adjacent to the middle turbinate, and attached to the nasal septum. The mass was excised using endoscopy, under local anesthesia. The histopathological examination showed a cannon-ball distribution of the vasculature, compatible with a tufted angioma. This is the first tufted angioma in the English literature found in the nasal mucosa, so we report this case with a literature review. PMID:23518006

  4. Tufted Angioma of Eyelid in an Adult - A Case Report

    PubMed Central

    Singh, Anshul; Misra, Vatsala; Singh, S. P.

    2016-01-01

    Tufted Angiomas also known as angioblastomas /Angioblastoma of Nagakawa are rare vascular neoplasms localised to the skin and subcutaneous tissues with the upper trunk and neck being most common sites. They are mainly seen in children but a few cases in juveniles and adults have been reported. We hereby report this case, a 40-year-old male who presented with a right lower lid, painless, slowly progressive, firm swelling diagnosed as Tufted Angioma on histopathology and immunohistochemistry. PMID:27504301

  5. ACQUIRED MULTIFOCAL TUFTED ANGIOMAS IN AN IMMUNOCOMPETENT YOUNG ADULT

    PubMed Central

    Ghosh, Sudip Kumar; Bandyopadhyay, Debabrata; Ghosh, Arghyaprasun; Biswas, Surajit Kumar; Barma, Kuntal Deb

    2011-01-01

    Tufted angioma (TA) is a rare benign vascular neoplasm, localized to the skin and subcutaneous tissues, occurring primarily on the trunk and extremities of children. The lesions are usually asymptomatic but, rarely, paroxysmal painful episodes may be associated. The occurrence of eruptive TA is still rarer and had been described almost exclusively in association with immunocompromised states. We report here a case of acquired painful multifocal tufted angiomas on the face and neck in an immunocompetent young adult. PMID:21965850

  6. Posterior foss avenous angiomas with drainage through the brain stem

    SciTech Connect

    Damiano, T.R.; Truwit, C.L. ); Dowd, C.F. ); Symonds, D.L. )

    1994-04-01

    To describe 11 cases of posterior fossa venous angiomas with drainage through the brain stem. Eleven cases of posterior fossa venous angioma with drainage through the brain stem were evaluated using MR. Correlation with known routes of venous drainage for the cerebellum and brain stem is made. Six of the 11 venous angiomas were found in the cerebellum, four in the brain stem; one involved both the cerebellum and brain stem. The cerebellar venous angiomas drained to subependymal veins about the fourth ventricle and dorsal pons. These then connected with an enlarged transmesencephalic or transpontine vein, to drain anteriorly to the anterior pontine veins. The brain stem angiomas had variable drainage depending on location. Evidence of hemorrhage was seen in five cases. Cerebellar and brain stem venous angiomas have several potential routes of drainage, including an enlarged vein traversing the pons, midbrain, or medulla. A knowledge of the normal venous anatomy of this region helps to understand the occurrence of these uncommon routes of venous drainage. 15 refs., 8 figs., 1 tab.

  7. Cavernous angioma of the optic chiasm--case report.

    PubMed

    Iwai, Y; Yamanaka, K; Nakajima, H; Miyaura, T

    1999-08-01

    A 31-year-old female presented with cavernous angioma originating from the optic chiasm manifesting as sudden onset of right retroorbital pain and right visual disturbance. She had a psychomotor seizure 10 years ago. Cavernous angioma at the right basal ganglia had been partially removed at that time. After the operation, the patient had left hemiparesis, but gradually improved. Neurological examination revealed decreased right visual acuity, left homonymous hemianopsia, and left hemiparesis. Magnetic resonance imaging revealed a mixed signal intensity mass at the right optic nerve to the optic chiasm with a low signal intensity rim on T2-weighted imaging, situated at the right basal ganglia where the cavernous angioma had been partially resected. Right frontotemporal craniotomy was performed by the pterional approach. A subpial hematoma was situated at the right optic nerve to the optic chiasm. The hematoma with an angiomatous component was completely resected from the surrounding structure. Histological examination of the specimens confirmed cavernous angioma. Postoperatively, her right visual acuity was slightly improved, but the visual field defect was unchanged. We emphasize the importance of correct diagnosis by magnetic resonance imaging and subsequent resection for preserving and improving the visual function of patients with cavernous angiomas of the optic chiasm. PMID:10487042

  8. Treatment of kaposiform hemangioendothelioma and tufted angioma.

    PubMed

    Liu, Xiao Han; Li, Jia Ying; Qu, Xin Hua; Yan, Wei Li; Zhang, Ling; Yang, Chi; Zheng, Jia Wei

    2016-10-01

    This meta-analysis was to evaluate the efficacy of current treatment modalities for kaposiform hemangioendothelioma and tufted angioma. A systematic review was performed using PubMed (Medline), Web of Science and Embase for clinical studies. The outcome was measured by pooled response rate with 95% confidence intervals (CIs), together with heterogeneity, subgroup analysis, sensitivity analysis and publication bias. Fifteen studies with 244 participants were included in this analysis. Vincristine therapy exhibited a relatively higher response rate (0.72; 95%CI, 0.64-0.79) compared with other therapies including systemic corticosteroid (0.27; 95%CI, 0.17-0.36), interferon (0.36; 95%CI, 0.24-0.48), radiotherapy (0.49; 95%CI, 0.26-0.73), embolization (0.66; 95%CI, 0.48-0.83), aspirin/ticlopidine (0.42; 95%CI, 0.06-0.78) and sirolimus (0.57; 95%CI, 0.00-0.10), in treating KHE/TA. Subgroup analysis indicated that the efficacy of systemic corticosteroids therapy was age-related. The pooled response rate was 0.15 (95%CI, 0.08-0.23) for participants 3.5 months of age and older compared with 0.35 (95% CI, 0.26-0.44) for participants less than 3.5 months. Regarding side effects, systemic corticosteroids treatment was 0.32 (95%CI, 0.15-0.50), vincristine modality was 0.16 (95%CI, 0.08-0.24) and interferon therapy was 0.28 (95%CI, 0.13-0.43). In conclusion, as one of the first reviews evaluating the effect of common therapies in the treatment of KHE/TA, our meta-analysis displayed that vincristine was more effective. Thus, vincristine was the most effective, providing evidence supporting the use of vincristine as a first-line therapy for KHE/TA. PMID:27252149

  9. Unilateral Glaucoma Associated with Conjunctival Angioma and Choroidal Thickening without Facial Angioma.

    PubMed

    Saeedi, Osamah J; Chang, Luke Y; Arora, Karun S; Jampel, Henry D; Quigley, Harry A

    2016-01-01

    We report a case of a suspected Sturge-Weber syndrome variant diagnosed at the age of 58 with the help of enhanced depth imaging spectral-domain ocular coherence tomography (EDI-SDOCT). A 58-year-old female with unilateral glaucoma was suspected to have choroidal vascular lesion, conjunctival angioma, and no facial port-wine stain who presented to the clinic with bleb dysesthesia many years after trabeculectomy. EDI-SDOCT was performed and revealed markedly increased choroidal thickness in the affected eye. EDI-SDOCT may be helpful in diagnosing Sturge-Weber variants without facial involvement and may aid in the investigation of the pathogenesis of this disease. PMID:27555719

  10. Unilateral Glaucoma Associated with Conjunctival Angioma and Choroidal Thickening without Facial Angioma

    PubMed Central

    Saeedi, Osamah J.; Chang, Luke Y.; Arora, Karun S.; Jampel, Henry D.; Quigley, Harry A.

    2016-01-01

    We report a case of a suspected Sturge–Weber syndrome variant diagnosed at the age of 58 with the help of enhanced depth imaging spectral-domain ocular coherence tomography (EDI-SDOCT). A 58-year-old female with unilateral glaucoma was suspected to have choroidal vascular lesion, conjunctival angioma, and no facial port-wine stain who presented to the clinic with bleb dysesthesia many years after trabeculectomy. EDI-SDOCT was performed and revealed markedly increased choroidal thickness in the affected eye. EDI-SDOCT may be helpful in diagnosing Sturge–Weber variants without facial involvement and may aid in the investigation of the pathogenesis of this disease. PMID:27555719

  11. Cavernous angioma with olivary hypertrophy and contralateral cerebellar diaschisis.

    PubMed

    Komaba, Y; Nomoto, T; Kitamura, S; Terashi, A

    1997-07-01

    We describe a 66-year-old man with a 20-year history of ataxic gait who suddenly developed diplopia on rightward gaze. Neurologic examination revealed right hemi-ataxia and hemi-hypesthesia, and left internuclear ophthalmoplegia. MRI showed a cavernous angioma in the left tectum, mild right cerebellar atrophy, and left interior olivary hypertrophy. Single photon emission computed tomography (SPECT) imaging demonstrated contralateral cerebellar diaschisis. We discuss the findings and review the literature concerning contralateral cerebellar diaschisis. PMID:9240502

  12. Cavernous angioma of the cauda equina: a case report and systematic review of the literature.

    PubMed

    Nie, Q-B; Chen, Z; Jian, F-Z; Wu, H; Ling, F

    2012-01-01

    Cavernous angioma is an uncommon vascular malformation of the central nervous system with a tumoural aspect. Spinal cavernous angioma mainly occurs within vertebral bodies; only 3-5% of tumours are located entirely in the vertebral canal. This case report describes a case of cavernous angioma, originating from the nerve roots of the cauda equina at the L1 level, in a 57-year-old woman presenting with acute lower back pain. The lesion was surgically resected 6 months after symptom onset and the structural integrity of the nerve root was maintained. Histopathological examination confirmed the diagnosis of cavernous angioma. The patient experienced no postoperative neurological deficit or recurrence. The diagnosis, histopathological features and surgical treatment of this case are presented, together with a literature review of clinical details and surgical procedures undertaken in cases of cavernous angioma of the cauda equina. PMID:23206484

  13. Tufted Angioma in Children: Report of Two Cases and a Review of the Literature

    PubMed Central

    da Silva, Alessandra Dutra; Ramos, Grasieli de Oliveira; Gomes, Rita Fabiane Teixeira; Martins, Marco Antônio Trevizani; Lamers, Marcelo Lazzaron; Santa'Ana Filho, Manoel; Rados, Pantelis Varvaki; Hildebrand, Laura de Campos; Visioli, Fernanda

    2014-01-01

    Tufted angioma (TA) is a benign vascular tumor with endothelial origin. It is extremely rare in oral mucosa; only seven cases have been reported in the literature so far. Here, we describe two cases of tufted angioma observed in children and we also present a review of the literature about this pathology, concerning the differential diagnosis and management of this lesion in children. PMID:25436158

  14. A field study of littoral processes in Estero Bay, California

    USGS Publications Warehouse

    Dingler, J.R.; Anima, R.J.; Molzan, D.E.; Luepke, Gretchen; Peterson, C.L.

    1982-01-01

    Estero Bay, which lies on the central California coast, has rocky headlands at both ends and sandy beaches within it. The shoreline of the bay has adjusted to be in equilibrium with the predominant wave climate, which is from the northwest. Because of its present shoreline configuration, the net southward littoral transport found along much of the California coast does not occur within Estero Bay. Instead, the sand primarily moves on- and offshore with a reversing longshore component. This sand transport pattern produces a littoral cell within Estero Bay even though there is no submarine canyon in the area. The primary sand sinks for this cell appear to be the sand spit south of Morro Rock and the entrance to Morro Bay itself, although this opinion was not experimentally verified. Field work during one summer (1978) and the following winter (1979) produced baseline data on the profile of and grain-size distribution across the littoral zone. In the offshore part of the littoral zone we also studied ripple size and type, internal structure, depth of erosion, and mineralogy. Although these data, which were collected along nine transects spaced 2 km apart, are inadequate to yield transport and energy rates, they indicate a northward decrease in wave energy within Estero Bay and a mixing of the sediments in the offshore. Box core and rod height data from grid points in seven meters of water showed that on the order of a meter of erosion occurred in the central part of the bay between the two sampling periods. Offshore, the data were incomplete, but at one station, in 17 m of water, at least 20 cm of erosion occurred.

  15. The clinical spectrum of kaposiform hemangioendothelioma and tufted angioma.

    PubMed

    Croteau, Stacy E; Gupta, Deepti

    2016-03-01

    Kasposiform hemoangioendothelioma (KHE) and tufted angioma (TA) are classifed as vascular tumors with locally aggressive and benign growth potential, respectively, within the classification schema proposed by the International Society for the Study of Vascular Anomalies. A unique feature of these vascular tumors is the risk of Kasabach-Merritt phenomenon (KMP), a severe thrombocytopenia with mild to moderate coagulopathy resulting from intralesional platelet trapping. As with many vascular anomalies, accurate description of clinical course, responses to therapy, and long-term outcomes have been hindered by lesion misidentification, imprecise nomenclature, and lack of prospective, randomized clinical trials to assess therapeutic efficacy. The classic dermatologic features of these lesions can facilitate diagnosis for the astute provider; however, the absence of or unusual integumentary involvement or presentation in a less common age group (adolescents/adults) poses a diagnostic challenge. Current approaches to the management of KHE/TA are often informed by lesion features such as presence of KMP, extent and location of the tumor, and symptomatology. Evidence-based treatment guidelines are limited. Corticosteroids, vincristine, interferon, multi-agent regimens and newer therapies, such as sirolimus, have demonstrated efficacy in patient series. The use of surgical excision and interventional radiology guided therapies have been described with mixed clinical benefit. Collaboration among emerging vascular anomaly centers and an increasing number of providers across subspecialties with interest in this field are facilitating the development of standardized approaches to diagnosis and management. The rarity of KHE-spectrum lesions and the heterogeneity of clinical manifestations necessitate rationally designed, multisite clinical trials to investigate risk stratification schemas and formally evaluate the short and long-term efficacy of available and novel therapies

  16. Venous angioma may be associated with epilepsy in children

    PubMed Central

    Kim, Bo Ryung; Lee, Yun Jin; Nam, Sang Ook

    2016-01-01

    Purpose Venous angioma (VA) is the most common congenital abnormality of the intracranial vasculature. This study aimed to investigate the relationship between VA and epilepsy and to identify the characteristics of children with VA and epilepsy. Methods The records of all patients aged less than 18 years who underwent brain magnetic resonance imaging (MRI) at Pusan National University Hospital were retrospectively reviewed. Patients with isolated VA and patients with normal MRI were compared in terms of the prevalence of epilepsy. Results In total, 2,385 pediatric patients who underwent brain MRI were enrolled. Isolated VA was identified in 26 patients (VA group). Among the patients with normal MRI findings, 225 age- and sex-matched patients to the VA-group were assigned to the control group. Nine patients in the VA group (9 of 26, 34.6%) and 27 patients in the control group (26 of 225, 11.5%; P<0.001) had epilepsy. In the VA group, 20 patients (76.9%) had the VA in the cerebral hemispheres, and 6 patients (23.1%) had the VA in the brainstem and cerebellum. The latter showed a higher prevalence of epilepsy (5 of 6, 83.3%) than the former (4 of 20, 20.0%; P=0.004). Among the nine patients who had epilepsy with VA, patients whose VA involved the brainstem and cerebellum showed a significantly higher frequency of abnormal Electroencephalographic findings than patients whose VA involved the cerebral hemispheres (P=0.016). Conclusion VA, especially in the brainstem and cerebellum, might be associated with epilepsy. PMID:27610183

  17. Holocene coastal dune fields used as indicators of net littoral transport: West Coast, USA

    USGS Publications Warehouse

    Peterson, C.D.; Stock, E.; Hart, R.; Percy, D.; Hostetler, S.W.; Knott, J.R.

    2010-01-01

    Between Point Grenville, Washington, and Point Conception, California (1500 km distance) 21 dune fields record longshore transport in 20 littoral cells during the late Holocene. The direction of predominant littoral transport is established by relative positions of dune fields (north, central, or south) in 17 representative littoral cells. Dune field position is north of cell midpoints in northernmost Oregon and Washington, but is south of cell midpoints in southern Oregon and California. Downdrift sand trapping occurs at significant changes in shoreline angle and/or at bounding headlands that project at least 2.5 km seaward from the general coastal trend. Sand bypassing occurs around small headlands of less than 0.5 km in projection distance. A northward shift of the winter low-pressure center in the northeast Pacific Ocean is modeled from 11 ka to 0 ka. Nearshore current forcing in southern Oregon and northern California switched from northward in earliest Holocene time to southward in late Holocene time. The late Holocene (5-0 ka) is generally characterized by net northward littoral drift in northernmost Oregon and Washington and by net southward littoral drift in southernmost Oregon and California. A regional divergence of net transport direction in central Oregon, i.e. no net drift, is consistent with modeled wind and wave forcing at the present time (0 ka). ?? 2009 Elsevier B.V.

  18. Tufted angioma of the maxilla: a rare case with unique clinical presentation.

    PubMed

    Katsoulas, Nikolaos; Nikitakis, Nikolaos; Theologie-Lygidakis, Nadia; Lianou, Violetta; Tsiklakis, Konstantinos; Iatrou, Ioannis; Sklavounou-Andrikopoulou, Alexandra

    2016-09-01

    Tufted angioma is an uncommon benign vascular tumor usually presenting in early childhood and affecting mainly the skin. It has been associated with Kasabach-Merritt syndrome, a severe coagulopathy of poor prognosis. There have been very few published cases of oral tufted angiomas, and maxillary bone involvement has not been hitherto reported. We present a case of a 10-year-old Caucasian boy with an erythematous left maxillary gingival mass accompanied by subjacent hard tissue swelling. Radiologic evaluation revealed an irregular mixed radiolucent and radiopaque area in the left maxilla, accompanied by alveolar ridge erosion, cortical plate expansion, and displacement and divergence of the premolars. The histopathologic examination showed scattered irregular tufted lobules of variably sized vascular spaces inside the subepithelial connective tissue and among the underlying bone trabeculae, exhibiting a "cannonball" appearance. Immunohistochemical evaluation found positivity for CD31, CD34, and smooth muscle actin, and a final diagnosis of tufted angioma with osseous involvement was rendered. A thorough review of the pertinent literature revealed only 9 previously published intraoral tufted angioma cases, the salient demographic and clinicopathologic features of which are summarized. PMID:26896438

  19. Does littoral sand bypass the head of Mugu Submarine Canyon? - a modeling study

    USGS Publications Warehouse

    Xu, Jingping; Elias, Edwin; Kinsman, Nicole

    2011-01-01

    A newly developed sand-tracer code for the process-based model Delft3D (Deltares, The Netherlands) was used to simulate the littoral transport near the head of the Mugu Submarine Canyon in California, USA. For westerly swells, which account for more than 90% of the wave conditions in the region, the sand tracers in the downcoast littoral drift were unable to bypass the canyon head. A flow convergence near the upcoast rim of the canyon intercepts the tracers and moves them either offshore onto the shelf just west of the canyon rim (low wave height conditions) or into the canyon head (storm wave conditions). This finding supports the notion that Mugu Canyon is the true terminus of the Santa Barbara Littoral Cell.

  20. [Recurrent bleeding of thalamic cavernous angioma under hormonal treatment. A case report].

    PubMed

    Gazzaz, M; Sichez, J; Capelle, L; Fohanno, D

    1999-12-01

    A case of recurrent bleeding from a probable left thalamic cavernoma in a 26 year old woman taking hormonal treatment is reported. Four episodes of bleeding were clinically and radiologically documented, prior to her referral to our institution. Interestingly, each episode occurred three weeks after starting hormonal treatment, dydrogesterone, desogestrel ethinylestradiol, chlormadin, nomegestrel acetate). The patient was not operated because of the deep situation of the cavernoma which was remote from the thalamic surface within the third ventricle. There was no recurrent bleeding after the onset hormonal treatment was discontinued. Although no similar case has been found in the literature, we believe that this case gives further argumentation in favor of a role of hormonal factors influencing the biological behavior of cavernous angiomas which has been previously suggested in pregnant females with bleeding cavernous angiomas. PMID:10717593

  1. Endoscopic transnasal septotomy for contralateral orbital apex venous angioma resection and decompression.

    PubMed

    Murray, Kim P; Mirani, Neena M; Langer, Paul D; Liu, James K; Eloy, Jean Anderson

    2013-02-01

    Tumors of the orbital apex region are traditionally difficult to approach surgically due to key anatomic structures found in this highly crowded region. We present a case of progressively enlarging orbital apex venous angioma treated with a novel endoscopic transnasal septotomy technique. We highlight the key steps to this approach, as well as specific landmarks necessary to achieve a safe and successful outcome. PMID:23347193

  2. Biological warfare in the littorals. Final report

    SciTech Connect

    Larsen, R.W.

    1997-05-01

    Biological warfare (BW) has emerged as a significant threat to military operations and is particularly challenging at the operational level of warfare in a littoral environment. There are compelling reasons why an operational commander should be concerned about BW: global proliferation of biotechnology and biological weapons capabilities; suitability of BW for disrupting force projection across the littorals; and the vulnerability of American, allied and coalition forces to BW. The threat of facing an adversary capable and willing to use biological weapons will influence the commander`s application of the operational art across the six operational functions. Degradation of operational tempo, effects of psychological responses among the force, and stress on the organizational structure may challenge the command and control process. Operational intelligence will demand robust integration of technical analysis, intentions and warnings, meteorological information, and medical intelligence. The maneuver and movement processes will be taxed to function effectively when ports and airfields offer such lucrative BW targets. Biological weapons may dictate the location of operational fires assets as well as the make-up of the target lists. Operational logistics assumes great importance in the medical functions, decontamination processes, and troop replacement and unit reconstitution. Operational protection encompasses nearly every aspect of BW defense and will demand a balance between what is necessary and what is possible to protect. As daunting as the challenges appear, the operational-level commander has at his disposal many tools necessary to prepare for biological warfare in the littorals. Ultimately, the commander must convince his force, his allies, and his enemies that the command can fight effectively in a BW environment, on land and sea.

  3. [Role of cryotherapy in the treatment of small angiomas of the oral cavity].

    PubMed

    Ragot, J P; Szpirglas, H; Vaillant, J M

    1984-01-01

    Operative difficulties when attempting to treat oral cavity angiomas suggested the use, of cryotherapy for limited lesions. The technique is simple in use non-aggressive and has few after effects. The principle of cryotherapy has been known for a long time, but it was only in the 60's that it was applied in ophthalmology, neurology, dermatology, gynecology and the treatment of hemorrhoids, as a result of the availability of new products: Freon, liquid nitrogen. Conclusions as to the value of cryotherapy are drawn from results obtained in buccal mucosa affections treated by this method over the last four years. PMID:6534251

  4. A Novel MGC4607/CCM2 Gene Mutation Associated with Cerebral Spinal and Cutaneous Cavernous Angiomas.

    PubMed

    Cigoli, M S; De Benedetti, S; Marocchi, A; Bacigaluppi, S; Primignani, P; Gesu, G; Citterio, A; Tassi, L; Mecarelli, O; Pulitano, P; Penco, S

    2015-07-01

    Cerebral cavernous malformations (CCMs) are vascular abnormalities that may cause seizures, headaches, intracerebral hemorrhages, and focal neurological deficits; they can also be clinically silent and occur as a sporadic or an autosomal dominant condition. Three genes have been identified as causing familial CCM: KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3, mapping, respectively, on chromosomes 7q, 7p, and 3q. Here, we report an Italian family affected by CCM due to a MGC4607 gene mutation, on exon 4. All the affected subjects suffered from seizures, and some of them underwent surgery for removal of a cavernous angioma. Brain MRI showed multiple lesions consistent with CCMs in all patients. Spinal and cutaneous cavernous angiomas were present too. This report underlines the need for a careful interdisciplinarity among neurologists, neuroradiologists, neurosurgeons, geneticists, ophthalmologists, and dermatologists for a total evaluation of the different manifestations of familial CCM. This points out that only referral centers are organized to offer a multidisciplinary management of this disease. PMID:25869611

  5. [A Case Report of Stereotactic Craniotomy for the Cerebral Cavernous Angioma].

    PubMed

    Ota, Yuichiro; Araki, Osamu; Oki, Shuichi; Inagawa, Tetsuji; Emoto, Katsuya; Shibukawa, Masaaki; Yamasaki, Hiroyuki; Kano, Yukari; Tani, Itaru

    2016-02-01

    A 59-year-old woman presented with right sensory loss and right hemiparesis. In February 2013, she was admitted to Araki Neurosurgical Hospital. A magnetic resonance imaging was performed that revealed a left temporal lobe hemorrhage. The image also showed a chronic stereotype hematoma. After 14 days of hospitalization, she underwent a stereotactic craniotomy. Subsequently, by postoperative pathological evaluation, the hematoma was diagnosed as a cavernous angioma. She had no postoperative complications. She was provided rehabilitation support and was discharged 28 days after the admission following which she rejoined work. A stereotactic craniotomy device is very useful in surgeries involving deep lesions. We present a case of stereotactic craniotomy and a few investigation reports. PMID:26856269

  6. Spider Angioma

    MedlinePlus

    ... Notice This Site and third parties who place advertisements on this Site may collect and use information ... Site and other websites in order to provide advertisements about goods and services of interest to you. ...

  7. EO system concepts in the littoral

    NASA Astrophysics Data System (ADS)

    Schwering, Piet B. W.; van den Broek, Sebastiaan P.; van Iersel, Miranda

    2007-04-01

    In recent years, operations executed by naval forces have taken place at many different locations. At present, operations against international terrorism and asymmetric warfare in coastal environments are of major concern. In these scenarios, the threat caused by pirates on-board of small surface targets, such as jetskis and fast inshore attack crafts, is increasing. In the littoral environment, the understanding of its complexity and the efficient use of the limited reaction time, are essential for successful operations. Present-day electro-optical sensor suites, also incorporating Infrared Search and Track systems, can be used for varying tasks as detection, classification and identification. By means of passive electro-optical systems, infrared and visible light sensors, improved situational awareness can be achieved. For long range capability, elevated sensor masts and flying platforms are ideally suited for the surveillance task and improve situational awareness. A primary issue is how to incorporate new electro-optical technology and signal processing into the new sensor concepts, to improve system performance. It is essential to derive accurate information from the high spatial-resolution imagery created by the EO sensors. As electro-optical sensors do not have all-weather capability, the performance degradation in adverse scenarios must be understood, in order to support the operational use of adaptive sensor management techniques. In this paper we discuss the approach taken at TNO in the design and assessment of system concepts for future IRST development. An overview of our maritime programme in future IRST and EO system concepts including signal processing is presented.

  8. Eruptive cherry angiomas and irritant symptoms after one acute exposure to the glycol ether solvent 2-butoxyethanol.

    PubMed

    Raymond, L W; Williford, L S; Burke, W A

    1998-12-01

    Seven clerical workers were evaluated in 1993, 8 months after exposure to vaporized 2-butoxyethanol (2-BE; also called butyl cellosolve or ethylene glycol monobutyl ether [EGMBE or EGBE]), which had been applied overnight to strip the floor of their file room. At the time of exposure, they had noted intense eye and respiratory irritation, marked dyspnea, nausea, and faintness, suggesting a concentration of 2-BE in the air of 200-300 parts per million (ppm). All seven workers later experienced recurrent eye and respiratory irritation, dry cough, and headache. Four months after the exposure, cherry angiomas began to appear on the arms, trunk, and thighs of six workers, who voiced concerns about the possibility of cancer. Our evaluation found no evidence of hematologic, liver, lung, or renal toxicity, but elevations in the erythrocyte sedimentation rate and blood pressure of each subject were found. Workplace air sampling found no detectable 2-BE, but traces (0.1-0.2 ppm) of formaldehyde were identified. Irritant symptoms abated after the group was moved to a room with better ventilation, and the mild hypertension gradually cleared, but new cherry angiomas have continued to appear 5 years after the acute exposure, as the initial ones persisted. These angiomas occur in healthy persons as they age but in this instance appear to have resulted from a single overexposure to 2-BE. We felt confident in reassuring the workers that they would suffer no serious consequences from this exposure. PMID:9871882

  9. Lake shoreline and littoral physical habitat structure in a national lakes assessment

    EPA Science Inventory

    Riparian and littoral habitat components are important to lake biological assemblages, providing refuge from predation, living and egg-laying substrates, and food. Shoreline structure also affects nutrient cycling, littoral production, and sedimentation rates. Measures of ripar...

  10. LETHALITY AND BIOACCUMULATION OF 4-NONYLPHENOL IN BLUEGILL SUNFISH IN LITTORAL ENCLOSURES

    EPA Science Inventory

    A comprehensive littoral enclosure study was conducted to assess the persistence and distribution of 4-nonylphenol (NP) om a littoral ecosystem and to evaluate the compound's effect on resident aquatic biota.

  11. Clinical Outcomes for Systemic Corticosteroids Versus Vincristine in Treating Kaposiform Hemangioendothelioma and Tufted Angioma

    PubMed Central

    Liu, Xiaohan; Li, Jiaying; Qu, Xinhua; Yan, Weili; Zhang, Ling; Zhang, Shanyong; Yang, Chi; Zheng, Jiawei

    2016-01-01

    Abstract A meta-analysis was performed to evaluate the efficacy and safety of systemic corticosteroids versus those of vincristine in the treatment of kaposiform hemangioendothelioma (KHE) and tufted angioma (TA). A literature search of PubMed, Embase, and Web of Science was performed for clinical studies on systemic corticosteroid versus vincristine therapies in treating KHE/TA. Pooled relative risks (RRs) and response rate with 95% confidence intervals (CIs) were used to measure outcomes. Heterogeneity, subgroup analysis, sensitivity analysis, and publication bias analysis were performed for result evaluation. Thirteen studies, comprising 344 participants, were used in the analysis. Vincristine therapy was found to be relatively more effective than systemic corticosteroids (RRs = 0.45, 95%CI: 0.35–0.58). The result of pooled adverse reactions response rate for systemic corticosteroids was 0.31 (95%CI, 0.18–0.43), significantly higher than that for vincristine, which was 0.12 (95%CI, 0.06–0.19). In subgroup analyses, factors including mean age and race of patients, and period of follow-up were examined as possible sources of heterogeneity. This is the first meta-analysis estimating the clinical outcomes of systemic corticosteroids in comparison with those of vincristine in the treatment of KHE/TA. The results showed that vincristine was considerably more effective with lower complication rates than systemic corticosteroids; thus, vincristine could be suggested as the first-line therapy for KHE/TA. PMID:27196448

  12. [How reliable is the diagnosis of spinal angiomas in the myelogram?].

    PubMed

    Thron, A; Mironov, A; Voigt, K

    1983-10-01

    Using water-soluble contrast media for thoracic myelography vascular structures can be outlined within the subarachnoid space in about 30% as distinct and in another 30% as faint contrast filling defects. The localization corresponds to the results of anatomical studies demonstrating the largest vessels in the lower thoracic region and at the lumbar enlargement. The extreme variability of size and course of spinal cord vessels can cause difficulties in separating normal and angioma-like vascular pattern in myelographic examinations. Out of 100 unselected cervico-thoracic myelographies, examples of normal vascular patterns are given and compared to pathological findings of angiographically verified angiomatous malformations. The limitations of diagnostic reliability are given by anatomical factors like variability of vessel size or width of the subarachnoid space, by secondary spinal arachnitis or by the differentiation of cord tumours with vascular congestion. Furthermore, inadequate angiographic studies can result in misinterpretation of myelograms. In cases of negative arteriograms other affections leading to raised pressure in the azygos- or caval vein should be considered. PMID:6647829

  13. EFFECTS OF CHLORPYRIOS ON MACROINVERTEBRATES IN LITTORAL ENCLOSURES

    EPA Science Inventory

    Aquatic enclosures constructed in the littoral zone of a 0.72 ha pond in central Minnesota, were used to evaluate the impact of a mosquito larvicide chlorpyrifos on endemic macroinvertebrate communities. Chlorpyrifos was acutely toxic to several macroinvertebrates at a peak conce...

  14. Microsurgical resection of a cavernous angioma that involves the optic pathway using a pterional approach: a case report and literature review.

    PubMed

    Sun, Xi-Yan; Yu, Feng

    2012-12-01

    Cavernous angiomas affecting the optic pathway are rare. This report describes the case of a 12-year-old girl who presented with a 10-month history of right-sided blurred vision caused by a cavernous angioma affecting the right side of the optic chiasm. The computed tomography (CT) scan demonstrated a hyperdense image with calcifications. T1-weighted magnetic resonance imaging (MRI) showed a sellar mass with uneven isointensities and hyperintensities, while T2-weighted showing a heterogeneous signal, which was initially misdiagnosed as a craniopharyngioma. The patient underwent complete resection of the mass using a pterional approach, which rapidly decompresses and protects the optic nerve function, rather than conservative treatment or cranial irradiation. Postoperative histopathology confirmed the diagnosis of a cavernous angioma. PMID:22577850

  15. Intralesional hemorrhage and thrombosis without rupture in a pure spinal epidural cavernous angioma: a rare cause of acute lumbal radiculopathy.

    PubMed

    Floeth, Frank; Riemenschneider, Markus; Herdmann, Jörg

    2010-07-01

    Pure spinal epidural cavernous angiomas are extremely rare lesions, and their normal shape is that of a fusiform mass in the dorsal aspects of the spinal canal. We report a case of a lumbo-sacral epidural cavernous vascular malformation presenting with acute onset of right-sided S1 radiculopathy. Clinical aspects, imaging, intraoperative findings, and histology are demonstrated. The patient, a 27-year-old man presented with acute onset of pain, paraesthesia, and numbness within the right leg corresponding to the S1 segment. An acute lumbosacral disc herniation was suspected, but MRI revealed a cystic lesion with the shape of a balloon, a fluid level and a thickened contrast-enhancing wall. Intraoperatively, a purple-blue tumor with fibrous adhesions was located between the right S1 and S2 nerve roots. Macroscopically, no signs of epidural bleedings could be denoted. After coagulation of a reticular venous feeder network and dissection of the adhesions the rubber ball-like lesion was resected in total. Histology revealed a prominent venous vessel with a pathologically thickened, amuscular wall surrounded by smaller, hyalinized, venous vessels arranged in a back-to-back position typical for the diagnosis of a cavernous angioma. Lumina were partially occluded by thrombi. The surrounding fibrotic tissue showed signs of recurrent bleedings. There was no obvious mass hemorrhage into the surrounding tissue. In this unique case, the pathologic mechanism was not the usual rupture of the cavernous angioma with subsequent intraspinal hemorrhage, but acute mass effect by intralesional bleedings and thrombosis with subsequent increase of volume leading to nerve root compression. Thus, even without a sudden intraspinal hemorrhage a spinal cavernous malformation can cause acute symptoms identical to the clinical features of a soft disc herniation. PMID:20213297

  16. Emergent littoral deposits in the eastern Canary Islands

    NASA Astrophysics Data System (ADS)

    Meco, Joaquin; Stearns, Charles E.

    1981-03-01

    K-Ar ages ( A. Abdel-Monem, P. D. Watkins, and P. W. Gast, 1971, American Journal of Science271, 490-521; this paper) and revised paleontological determinations ( J. Meco, 1977, "Los Strombus neogenos y cuatenarios del Atlantico euroafricano", Las Palmas, Ediciones del Excmo. Cabildo Insular de Gran Canaria) show that "Quaternary" ( R. Crofts, 1967, Quaternaria 9, 247-260; G. Lecointre, K. J. Tinkler, and G. Richards, 1967, Academy of Natural Science of Philadelphia Proceedings119, 325-344) littoral deposits on Lanzarote and Fuerteventura are early Pliocene and late Pleistocene. Early and middle Pleistocene strand lines are not represented. Early Pliocene littoral and marine deposits contain a characteristic fossil assemblage: Strombus coronatus, Nerità emiliana, Gryphaea virleti, Patella cf. intermedia, and Rothpletzia rudista. Differences in elevation record differential post-Pliocene uplift of the coastal platforms on which they lie. Late Pleistocene beach deposits at low elevations belong to two groups, an older with Strombus bubonius and a younger without. Differences in elevation of early Pliocene littoral deposits are reflected by differences in elevation of late Pleistocene beach deposits nearby.

  17. Developmental venous anomalies and cavernous angiomas: a review of the concurrence, imaging, and treatment of these vascular malformations.

    PubMed

    Beall, Douglas P; Bell, Jayson P; Webb, James R; Fish, Jon R

    2005-11-01

    Deep venous anomalies and cavernous angiomas are two distinct intracranial lesions. Although these lesions can be found in association with each other, they have different pathologic characteristics and developmental mechanisms. These lesions can produce a variety of clinical symptoms or in some cases can be asymptomatic. The management of these anomalies can include conservative measures in some cases and aggressive intervention in others. Several imaging modalities can be used to evaluate these distinct lesions and often more than one are needed for a prompt and reliable diagnosis. Because of the tendency of these lesions to occur simultaneously, thorough evaluation of these anomalies and their surrounding tissues is critical in their clinical management. In this review, the characteristics and radiographic evaluation of these lesions will be presented and the therapeutic options for these anomalies will be discussed. PMID:16379482

  18. Littoral processes: US Coast Guard Station, Fort Point, San Francisco

    SciTech Connect

    Ecker, R.M.; Whelan, G.

    1983-10-01

    The US Coast Guard Station, Fort Point is located three-quarters of a nautical mile southeast of the Golden Gate Strait, the entrance to San Francisco Bay. The existing storm wave conditions at Fort Point Station pier make it extremely dangerous for the SAR crews to get on and off the Motor Life Boats at times requiring the vessels to be moored at the San Francisco Yacht Harbor about 1.5 miles east of the Fort Point Station. To mitigate these harsh working conditions the US Coast Guard is considering the feasibility of constructing suitable all-weather moorings for the three Motor Life Boats at the Fort Point Station to enable unimpeded SAR operations, to provide safe working conditions for Coast Guard small boat crews, and to improve small boat maintenance conditions at Fort Point Station. The purpose of this report is to identify, analyze and evaluate physical environmental factors that could affect all-weather moorings siting, configuration and entrance location, as well as potential post construction alterations to littoral conditions and processes. This report includes a description of the site, description of pertinent littoral processes, evaluation of how these processes could affect construction of all-weather moorings, and discussion of design considerations, as well as mitigation measures to minimize potential adverse effects to the physical environment. 19 references, 27 figures, 26 tables.

  19. Littoral environmental reconnaissance using tactical imagery from unmanned aircraft systems

    NASA Astrophysics Data System (ADS)

    Holland, K. Todd; Lalejini, David M.; Spansel, Steven D.; Holman, Robert A.

    2010-04-01

    The dynamic nature of littoral regions requires a reconnaissance approach that can rapidly quantify environmental conditions. Inadequate estimation of these conditions can have substantial impacts on the performance of Naval systems. Given that expeditionary warfare operations can occur over timescales on the order of hours, exploitation of video imagery from tactical vehicles such as Unmanned Aircraft Systems (UAS) has proved to be a reliable and adaptive solution. Tactical littoral products that can be created by exploiting UAS imagery include estimates of surf conditions, dominant wave period, wave direction, nearshore currents, and bathymetry. These vehicles can fly for durations of 1-2 hours at altitudes of less than 1000 m (beneath typical cloud cover) to obtain imagery at pixel resolutions better than 1 m. The main advantage of using imaging sensors carried by these vehicles is that the data is available in the region of operational interest where other data collection approaches would be difficult or impossible to employ. The through-the-sensor exploitation technique we have developed operates in two phases. The first step is to align individual image frames to a common reference and then georegister the alignment into a mapped image sequence. The second phase involves signal processing of pixel intensity time series (virtual sensors) to determine spatial relationships over time. Geophysical relationships, such as linear wave dispersion, can then be applied to these processed data to invert for environmental parameters such as bathymetry.

  20. Littoral lichens as a novel source of potentially bioactive Actinobacteria

    PubMed Central

    Parrot, Delphine; Antony-Babu, Sanjay; Intertaglia, Laurent; Grube, Martin; Tomasi, Sophie; Suzuki, Marcelino T.

    2015-01-01

    Cultivable Actinobacteria are the largest source of microbially derived bioactive molecules. The high demand for novel antibiotics highlights the need for exploring novel sources of these bacteria. Microbial symbioses with sessile macro-organisms, known to contain bioactive compounds likely of bacterial origin, represent an interesting and underexplored source of Actinobacteria. We studied the diversity and potential for bioactive-metabolite production of Actinobacteria associated with two marine lichens (Lichina confinis and L. pygmaea; from intertidal and subtidal zones) and one littoral lichen (Roccella fuciformis; from supratidal zone) from the Brittany coast (France), as well as the terrestrial lichen Collema auriforme (from a riparian zone, Austria). A total of 247 bacterial strains were isolated using two selective media. Isolates were identified and clustered into 101 OTUs (98% identity) including 51 actinobacterial OTUs. The actinobacterial families observed were: Brevibacteriaceae, Cellulomonadaceae, Gordoniaceae, Micrococcaceae, Mycobacteriaceae, Nocardioidaceae, Promicromonosporaceae, Pseudonocardiaceae, Sanguibacteraceae and Streptomycetaceae. Interestingly, the diversity was most influenced by the selective media rather than lichen species or the level of lichen thallus association. The potential for bioactive-metabolite biosynthesis of the isolates was confirmed by screening genes coding for polyketide synthases types I and II. These results show that littoral lichens are a source of diverse potentially bioactive Actinobacteria. PMID:26514347

  1. Littoral lichens as a novel source of potentially bioactive Actinobacteria.

    PubMed

    Parrot, Delphine; Antony-Babu, Sanjay; Intertaglia, Laurent; Grube, Martin; Tomasi, Sophie; Suzuki, Marcelino T

    2015-01-01

    Cultivable Actinobacteria are the largest source of microbially derived bioactive molecules. The high demand for novel antibiotics highlights the need for exploring novel sources of these bacteria. Microbial symbioses with sessile macro-organisms, known to contain bioactive compounds likely of bacterial origin, represent an interesting and underexplored source of Actinobacteria. We studied the diversity and potential for bioactive-metabolite production of Actinobacteria associated with two marine lichens (Lichina confinis and L. pygmaea; from intertidal and subtidal zones) and one littoral lichen (Roccella fuciformis; from supratidal zone) from the Brittany coast (France), as well as the terrestrial lichen Collema auriforme (from a riparian zone, Austria). A total of 247 bacterial strains were isolated using two selective media. Isolates were identified and clustered into 101 OTUs (98% identity) including 51 actinobacterial OTUs. The actinobacterial families observed were: Brevibacteriaceae, Cellulomonadaceae, Gordoniaceae, Micrococcaceae, Mycobacteriaceae, Nocardioidaceae, Promicromonosporaceae, Pseudonocardiaceae, Sanguibacteraceae and Streptomycetaceae. Interestingly, the diversity was most influenced by the selective media rather than lichen species or the level of lichen thallus association. The potential for bioactive-metabolite biosynthesis of the isolates was confirmed by screening genes coding for polyketide synthases types I and II. These results show that littoral lichens are a source of diverse potentially bioactive Actinobacteria. PMID:26514347

  2. Toxic effects of decomposing red algae on littoral organisms

    NASA Astrophysics Data System (ADS)

    Eklund, Britta; Svensson, Andreas P.; Jonsson, Conny; Malm, Torleif

    2005-03-01

    Large masses of filamentous red algae of the genera Polysiphonia, Rhodomela, and Ceramium are regularly washed up on beaches of the central Baltic Sea. As the algal masses start to decay, red coloured effluents leak into the water, and this tinge may be traced several hundred meters off shore. In this study, possible toxic effects of these effluents were tested on littoral organisms from different trophic levels. Effects on fertilisation, germination and juvenile survival of the brown seaweed Fucus vesiculosus were investigated, and mortality tests were performed on the crustaceans Artemia salina and Idotea baltica, as well as on larvae and adults of the fish Pomatoschistus microps. Fucus vesiculosus was the most sensitive species of the tested organisms to the red algal extract. The survival of F. vesiculosus recruits was reduced with 50% (LC50) when exposed to a concentration corresponding to 1.7 g l -1 dw red algae. The lethal concentration for I. baltica, A. salina and P. microps were approximately ten times higher. The toxicity to A. salina was reduced if the algal extract was left to decompose during two weeks but the decline in toxicity was not affected by different light or temperature conditions. This study indicates that the filamentous red algae in the central Baltic Sea may produce and release compounds with negative effects on the littoral ecosystem. The effects may be particularly serious for the key species F. vesiculosus, which reproduce in autumn when filamentous red algal blooms are most severe.

  3. Edge detection of red hind grouper vocalizations in the littorals

    NASA Astrophysics Data System (ADS)

    Matthews, Cameron A.; Beaujean, Pierre-Philippe

    2016-05-01

    Littoral regions typically present to passive sensors as a high noise acoustic environment, particularly with respect to port and harbor regions where tidal variation, often characterized as pink, mixes with reverberation from on-shore business and commercial shipping, often characterized as white. Some fish in these regions, in particular epiphenalius Guttatus or more commonly the red hind grouper, emit relatively narrowband tones in low frequencies to communicate with other fish in such regions. The impact of anthropogenic noise sources on the red Hind and other fish is a topical area of interest for wildlife fisheries, private sportsmen and military offices that is not considered here; the fact that fish species continue to populate and communicate in these regions in the presence of high noise content lends some study to the signal content and modeling of a potential biologically inspired receiver structure.

  4. Physical habitat structure of the lake shoreline and littoral zone -- How important is it?

    EPA Science Inventory

    The recent National Lakes Assessment (NLA) included the first national assessment of littoral and lakeshore physical habitat. It quantified water depth, surface characteristics, bank morphology, lake level fluctuations, substrate, fish concealment features, aquatic macrophytes, l...

  5. AN INTEGRATED EVALUATION OF THE PERSISTENCE AND EFFECTS OF 4-NONYLPHENOL IN AN EXPERIMENTAL LITTORAL ECOSYSTEM

    EPA Science Inventory

    Toxicity and bioaccumulation in bluegill sunfish (Lepomis macrochirus) of 4-nonphenyol (NP), a common precursor and degradation intermediate of certain nonionic surfactants, were evaluated in a set of 18 aquatic mesocosms (littoral enclosures) in northeastern Minnesota. Nonylphe...

  6. Small lakes in big landscape: Multi-scale drivers of littoral ecosystem in alpine lakes.

    PubMed

    Zaharescu, Dragos G; Burghelea, Carmen I; Hooda, Peter S; Lester, Richard N; Palanca-Soler, Antonio

    2016-05-01

    In low nutrient alpine lakes, the littoral zone is the most productive part of the ecosystem, and it is a biodiversity hotspot. It is not entirely clear how the scale and physical heterogeneity of surrounding catchment, its ecological composition, and larger landscape gradients work together to sustain littoral communities. A total of 113 alpine lakes from the central Pyrenees were surveyed to evaluate the functional connectivity between littoral zoobenthos and landscape physical and ecological elements at geographical, catchment and local scales, and to ascertain how they affect the formation of littoral communities. At each lake, the zoobenthic composition was assessed together with geolocation, catchment hydrodynamics, geomorphology and topography, riparian vegetation composition, the presence of trout and frogs, water pH and conductivity. Multidimensional fuzzy set models integrating benthic biota and environmental variables revealed that at geographical scale, longitude unexpectedly surpassed altitude and latitude in its effect on littoral ecosystem. This reflects a sharp transition between Atlantic and Mediterranean climates and suggests a potentially high horizontal vulnerability to climate change. Topography (controlling catchment type, snow coverage and lakes connectivity) was the most influential catchment-scale driver, followed by hydrodynamics (waterbody size, type and volume of inflow/outflow). Locally, riparian plant composition significantly related to littoral community structure, richness and diversity. These variables, directly and indirectly, create habitats for aquatic and terrestrial stages of invertebrates, and control nutrient and water cycles. Three benthic associations characterised distinct lakes. Vertebrate predation, water conductivity and pH had no major influence on littoral taxa. This work provides exhaustive information from relatively pristine sites, and unveils a strong connection between littoral ecosystem and catchment

  7. Primary and secondary neoplasms of the spleen

    PubMed Central

    Azar, S.; Al-Hawary, M.M.; Francis, I.R.

    2010-01-01

    Abstract With the exception of lymphoma involving the spleen, other primary and secondary neoplasms are rare and infrequently encountered. Primary malignant neoplasms involving the spleen are lymphoma and angiosarcoma. Primary benign neoplasms involving the spleen include hemangioma, lymphangioma, littoral cell angioma and splenic cyst and solid lesions such as hamartoma and inflammatory pseudotumor. PMID:20713317

  8. DARLA: Data Assimilation and Remote Sensing for Littoral Applications

    NASA Astrophysics Data System (ADS)

    Jessup, A.; Holman, R. A.; Chickadel, C.; Elgar, S.; Farquharson, G.; Haller, M. C.; Kurapov, A. L.; Özkan-Haller, H. T.; Raubenheimer, B.; Thomson, J. M.

    2012-12-01

    DARLA is 5-year collaborative project that couples state-of-the-art remote sensing and in situ measurements with advanced data assimilation (DA) modeling to (a) evaluate and improve remote sensing retrieval algorithms for environmental parameters, (b) determine the extent to which remote sensing data can be used in place of in situ data in models, and (c) infer bathymetry for littoral environments by combining remotely-sensed parameters and data assimilation models. The project uses microwave, electro-optical, and infrared techniques to characterize the littoral ocean with a focus on wave and current parameters required for DA modeling. In conjunction with the RIVET (River and Inlets) Project, extensive in situ measurements provide ground truth for both the remote sensing retrieval algorithms and the DA modeling. Our goal is to use remote sensing to constrain data assimilation models of wave and circulation dynamics in a tidal inlet and surrounding beaches. We seek to improve environmental parameter estimation via remote sensing fusion, determine the success of using remote sensing data to drive DA models, and produce a dynamically consistent representation of the wave, circulation, and bathymetry fields in complex environments. The objectives are to test the following three hypotheses: 1. Environmental parameter estimation using remote sensing techniques can be significantly improved by fusion of multiple sensor products. 2. Data assimilation models can be adequately constrained (i.e., forced or guided) with environmental parameters derived from remote sensing measurements. 3. Bathymetry on open beaches, river mouths, and at tidal inlets can be inferred from a combination of remotely-sensed parameters and data assimilation models. Our approach is to conduct a series of field experiments combining remote sensing and in situ measurements to investigate signature physics and to gather data for developing and testing DA models. A preliminary experiment conducted at

  9. High methane emissions from a littoral zone on the Qinghai-Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Chen, Huai; Wu, Ning; Yao, Shouping; Gao, Yongheng; Zhu, Dan; Wang, Yanfen; Xiong, Wan; Yuan, Xingzhong

    The littoral zones of lakes have been regarded as hotspots of methane (CH 4) fluxes through several studies. In the present study, we measured CH 4 fluxes in six kinds of littoral zones of Huahu Lake on the Qinghai-Tibetan Plateau in the peak growing season of 2006 and 2007. We found that CH 4 efflux (ranging from -0.1 to 90 mg CH 4 m -2 h -1) from the littoral zones of this lake was relatively high among those of boreal and temperate lakes. Our results also showed that emergent plant zones ( Hippuris vulgaris and Glyceria maxima stands) recorded the highest CH 4 flux rate. The CH 4 flux in the floating mat zone of Carex muliensis was significantly lower than those of the emergent plant zones. CH 4 fluxes in the floating-leaved zone of Polygonum amphibium and bare lakeshore showed no significant difference and ranked last but one, only higher than that of the littoral meadow ( Kobresia tibetica). Plant biomass and standing water depths were important factors to explain such spatial variations in CH 4 fluxes. No significant temporal variations in CH 4 fluxes were found due to the insignificant variations of physical factors in the peak growing season. These results may help in our understanding of the importance of the littoral zone of lakes, especially the emergent plant zone, as a hotspot of CH 4 emission.

  10. Modeling the effects of wave skewness and beach cusps on littoral sand transport

    USGS Publications Warehouse

    Haas, K.A.; Check, L.A.; Hanes, D.M.

    2008-01-01

    A process-based numerical modeling system is utilized for predicting littoral sand transport. The intent is to examine conditions slightly more complex than linear waves impinging upon a plane beach. Two factors that we examine are wave skewness and longshore varying bathymetry. An empirical model is used for calculating the skewed bottom wave orbital velocity. The advection of sediment due to the skewed wave velocity is larger and in the direction of the waves, opposite to the results with sinusoidal wave velocities, due to the increase in the bottom shear stress under the wave crests. The model system is also applied to bathymetry containing beach cusps. When the wave field has relatively weak longshore wave power, the currents and the littoral transport exhibit significant longshore variability, thereby altering the overall mean littoral transport.

  11. Development of a regional littoral benthic macroinvertebrate multi-metric index (MMI) for lakes from the National Lakes Assessment

    EPA Science Inventory

    During the 2007 National Lakes Assessment (NLA) benthic macroinvertebrate samples were collected from the lake littoral zone. The purpose of the sampling was to assess the feasibility of a multi-metric index (MMI) to assess the condition of the littoral benthic macroinvertebrate...

  12. Wide-area littoral discreet observation: success at the tactical edge

    NASA Astrophysics Data System (ADS)

    Toth, Susan; Hughes, William; Ladas, Andrew

    2012-06-01

    In June 2011, the United States Army Research Laboratory (ARL) participated in Empire Challenge 2011 (EC-11). EC-11 was United States Joint Forces Command's (USJFCOM) annual live, joint and coalition intelligence, surveillance and reconnaissance (ISR) interoperability demonstration under the sponsorship of the Under Secretary of Defense for Intelligence (USD/I). EC-11 consisted of a series of ISR interoperability events, using a combination of modeling & simulation, laboratory and live-fly events. Wide-area Littoral Discreet Observation (WALDO) was ARL's maritime/littoral capability. WALDO met a USD(I) directive that EC-11 have a maritime component and WALDO was the primary player in the maritime scenario conducted at Camp Lejeune, North Carolina. The WALDO effort demonstrated the utility of a networked layered sensor array deployed in a maritime littoral environment, focusing on maritime surveillance targeting counter-drug, counter-piracy and suspect activity in a littoral or riverine environment. In addition to an embedded analytical capability, the sensor array and control infrastructure consisted of the Oriole acoustic sensor, iScout unattended ground sensor (UGS), OmniSense UGS, the Compact Radar and the Universal Distributed Management System (UDMS), which included the Proxy Skyraider, an optionally manned aircraft mounting both wide and narrow FOV EO/IR imaging sensors. The capability seeded a littoral area with riverine and unattended sensors in order to demonstrate the utility of a Wide Area Sensor (WAS) capability in a littoral environment focused on maritime surveillance activities. The sensors provided a cue for WAS placement/orbit. A narrow field of view sensor would be used to focus on more discreet activities within the WAS footprint. Additionally, the capability experimented with novel WAS orbits to determine if there are more optimal orbits for WAS collection in a littoral environment. The demonstration objectives for WALDO at EC-11 were

  13. [Selective photothermolysis: contribution to the treatment of flat angiomas (port wine stains) by laser].

    PubMed

    Polla, L L; Jacques, S L; Margolis, R J; Prince, M R; Anderson, R R; Parrish, J A; Tan, O T

    1987-01-01

    Since 1962, lasers have been used in dermatology and have become the first choice in the treatment of superficial, vascular ectasia. Lasers are unique sources of light; they are coherent, monochromatic, collimated and intense. By careful selection of wavelength, pulse duration, and intensity, it is often possible to selectively confine a laser effect to a specific histologic structure in tissue, depending upon the tissue properties. The ideal treatment of Port Wine Stains (PWS) should irreversibly damage the ectatic vessels but minimize heating of the epidermis and superficial dermis. A theory, called selective photothermolysis, predicts the optimal combination of laser parameters of achieving this ideal treatment of PWS to be a wavelength of 577 nm, a pulse duration of 0.35-10 msec, and an energy per surface area of about 7-8 J/cm2. Laser wavelength: The wavelength of 577 nm is preferred because it: maximizes the selective absorption by hemoglobin, minimizes absorption by epidermal melanin, provides sufficient depth of penetration in the blood to coagulate 0.1 mm vessels allows penetration of light into dermis up to 1 mm. Laser pulse duration: A pulse-width in the range of 0.35-10 msec allows the temperature elevation to be uniform inside the vessel and to be confined to the vessel area. Shorter pulses superheat the red blood cells causing explosive boiling and hemorrhage. Longer pulses allow heat to diffuse away from vessels, requiring greater energies per pulse to achieve vessel damage. An increased energy per pulse increases the risk of excessive damage to surrounding tissue.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3619296

  14. Littoral assessment of mine burial signatures (LAMBS): buried-landmine hyperspectral data collections

    NASA Astrophysics Data System (ADS)

    Kenton, Arthur C.; Geci, Duane M.; McDonald, James A.; Ray, Kristofer J.; Thomas, Clayton M.; Holloway, John H., Jr.; Petee, Danny A.; Witherspoon, Ned H.

    2003-09-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies project's Littoral Assessment of Mine Burial Signatures (LAMBS) contract is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines located in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. The LAMBS program further expands the hyperspectral database previously collected and analyzed on the U.S. Army's Hyperspectral Mine Detection Phenomenology program [see "Detection of Land Mines with Hyperspectral Data," and "Hyperspectral Mine Detection Phenomenology Program," Proc. SPIE Vol. 3710, pp 917-928 and 819-829, AeroSense April 1999] to littoral areas where tidal, surf, and wind action can additionally modify spectral signatures. This work summarizes the LAMBS buried mine collections conducted at three beach sites - an inland bay beach site (Eglin AFB, FL, Site A-22), an Atlantic beach site (Duck, NC), and a Gulf beach site (Eglin AFB, FL, Site A-15). Characteristics of the spectral signatures of the various dry and damp beach sands are presented. These are then compared to buried land mine signatures observed for the tested background types, burial ages, and environmental conditions experienced.

  15. A comparison of shoreline seines with fyke nets for sampling littoral fish communities in floodplain lakes

    USGS Publications Warehouse

    Clark, S.J.; Jackson, J.R.; Lochmann, S.E.

    2007-01-01

    We compared shoreline seines with fyke nets in terms of their ability to sample fish species in the littoral zone of 22 floodplain lakes of the White River, Arkansas. Lakes ranged in size from less than 0.5 to 51.0 ha. Most contained large amounts of coarse woody debris within the littoral zone, thus making seining in shallow areas difficult. We sampled large lakes (>2 ha) using three fyke nets; small lakes (<2 ha) were sampled using two fyke nets. Fyke nets were set for 24 h. Large lakes were sampled with an average of 11 seine hauls/ lake and small lakes were sampled with an average of 3 seine hauls/lake, but exact shoreline seining effort varied among lakes depending on the amount of open shoreline. Fyke nets collected more fish and produced greater species richness and diversity measures than did seining. Species evenness was similar for the two gear types. Two species were unique to seine samples, whereas 13 species and 3 families were unique to fyke-net samples. Although fyke nets collected more fish and more species than did shoreline seines, neither gear collected all the species present in the littoral zone of floodplain lakes. These results confirm the need for a multiple-gear approach to fully characterize the littoral fish assemblages in floodplain lakes. ?? Copyright by the American Fisheries Society 2007.

  16. Littoral and Shoreline Wood in Mid-continent Great Rivers (USA)

    EPA Science Inventory

    Less is known about the ecology of wood in great rivers than in smaller lotic systems. We used a probability survey to estimate the abundance of littoral and shoreline wood along the mid-continent great rivers of the United States: the Missouri, Upper Mississippi, and the Ohio Ri...

  17. Life on the boundary: Environmental factors as drivers of habitat distribution in the littoral zone

    NASA Astrophysics Data System (ADS)

    Cefalì, Maria Elena; Cebrian, Emma; Chappuis, Eglantine; Pinedo, Susana; Terradas, Marc; Mariani, Simone; Ballesteros, Enric

    2016-04-01

    The boundary between land and sea, i.e. the littoral zone, is home to a large number of habitats whose distribution is primarily driven by the distance to the sea level but also by other environmental factors such as littoral's geomorphological features, wave exposure, water temperature or orientation. Here we explore the relative importance of those major environmental factors that drive the presence of littoral rocky habitats along 1100 Km of Catalonia's shoreline (Spain, NW Mediterranean) by using Geographic Information Systems and Generalized Linear Models. The distribution of mediolittoral and upper infralittoral habitats responded to different environmental factors. Mediolittoral habitats showed regional differences drawn by sea-water temperature and substrate type. Wave exposure (hydrodynamism), slope and geological features were only relevant to those mediolittoral habitats with specific environmental needs. We did not find any regional pattern of distribution in upper infralittoral habitats, and selected factors only played a moderate role in habitat distribution at the local scale. This study shows for the first time that environmental factors determining habitat distribution differ within the mediolittoral and the upper infralittoral zones and provides the basis for further development of models oriented at predicting the distribution of littoral marine habitats.

  18. SAMPLING LARVAL FISH IN THE LITTORAL ZONE OF WESTERN LAKE ERIE

    EPA Science Inventory

    Sampling techniques for larval fish were evaluated in the littoral zone (1- to 6-m deep) of western Lake Erie in 1975 and 1976. Catch rates were compared using slow-speed, 1-m-diameter plankton nets in daytime and nighttime oblique and stratified tows above bottom and in daytime ...

  19. Brainstem Cavernous Angioma

    MedlinePlus

    ... through the floor of this ventricle. Stereotactic radiosurgery (“gamma knife”) is generally not an accepted method of treatment ... Nakagawara J, Suematsu K, Nakamura J, Nagashima K. Gamma Knife surgery for angiographically occult vascular malformations. Stereotact Funct ...

  20. Cavernous Angioma and Children

    MedlinePlus

    ... neurologist to see if there might be an alternative medication. Children with even mild muscle weakness or decreased coordination resulting from a cavernous malformation bleed often have reduced physical stamina. It simply requires more energy to use legs that feel heavy or that ...

  1. Suitability of Taxodium distichum for Afforesting the Littoral Zone of the Three Gorges Reservoir

    PubMed Central

    Li, Bo; Du, Chunlan; Yuan, Xingzhong; Willison, J. H. Martin; Xiao, Hongyan

    2016-01-01

    The littoral zone ecosystem of the Three Gorges Reservoir (TGR) has become significantly degraded by annual cycles of prolonged winter flooding and summer drought. For purposes of flood control and sediment management, the water level in the reservoir is lowered by 30 m during the summer monsoon season and raised again to 175 m above sea level each year at the end of the monsoon period. To explore an effective way to promote biodiversity and associated ecosystem services, we examined Taxodium distichum as a species for afforesting the littoral zone. Sapling growth variations were measured after two rounds of winter flooding. Dominant influence factors were determined by redundancy analysis. Herb community similarities between the experimental afforested areas and nearby control areas were assessed to detect the ecosystem influence of the experimental afforestation. 94.5% of saplings planted at elevations above 168 m survived. All measured growth indices (tree height, diameter at breast height, crown width and foliage density) decreased as the flood depth increased. Completely submerged saplings had a mean dieback height of -0.65 m. Greater initial foliage density led to increased tree height and stem diameter. Shannon-Wiener indices were not significantly different between plots in experimental and control areas, but the low similarity of herb communities between experimental and control areas (0.242 on average) suggested that afforestation would enrich plant community structure and improve littoral zone ecosystem stability. Because littoral zone afforestation provides several ecosystem services (habitat, carbon sink, water purification and landscaping), it is a promising revegetation model for the TGR. PMID:26771509

  2. Suitability of Taxodium distichum for Afforesting the Littoral Zone of the Three Gorges Reservoir.

    PubMed

    Li, Bo; Du, Chunlan; Yuan, Xingzhong; Willison, J H Martin; Xiao, Hongyan

    2016-01-01

    The littoral zone ecosystem of the Three Gorges Reservoir (TGR) has become significantly degraded by annual cycles of prolonged winter flooding and summer drought. For purposes of flood control and sediment management, the water level in the reservoir is lowered by 30 m during the summer monsoon season and raised again to 175 m above sea level each year at the end of the monsoon period. To explore an effective way to promote biodiversity and associated ecosystem services, we examined Taxodium distichum as a species for afforesting the littoral zone. Sapling growth variations were measured after two rounds of winter flooding. Dominant influence factors were determined by redundancy analysis. Herb community similarities between the experimental afforested areas and nearby control areas were assessed to detect the ecosystem influence of the experimental afforestation. 94.5% of saplings planted at elevations above 168 m survived. All measured growth indices (tree height, diameter at breast height, crown width and foliage density) decreased as the flood depth increased. Completely submerged saplings had a mean dieback height of -0.65 m. Greater initial foliage density led to increased tree height and stem diameter. Shannon-Wiener indices were not significantly different between plots in experimental and control areas, but the low similarity of herb communities between experimental and control areas (0.242 on average) suggested that afforestation would enrich plant community structure and improve littoral zone ecosystem stability. Because littoral zone afforestation provides several ecosystem services (habitat, carbon sink, water purification and landscaping), it is a promising revegetation model for the TGR. PMID:26771509

  3. Carbon dioxide and methane fluxes in the littoral zones of two lakes, east Antarctica

    NASA Astrophysics Data System (ADS)

    Zhu, Renbin; Liu, Yashu; Xu, Hua; Huang, Tao; Sun, Jianjun; Ma, Erdeng; Sun, Liguang

    2010-01-01

    During the summertime of 2007/2008, carbon dioxide (CO 2) and methane (CH 4) fluxes across air-water interface were investigated in the littoral zones of Lake Mochou and Lake Tuanjie, east Antarctica, using a static chamber technique. The mean fluxes of CO 2 and CH 4 were -70.8 mgCO 2 m -2 h -1 and 144.6 μgCH 4 m -2 h -1, respectively, in the littoral zone of Lake Mochou; The mean fluxes were -36.9 mgCO 2 m -2 h -1 and 109.8 μgCH 4 m -2 h -1, respectively, in the littoral zone of Lake Tuanjie. Their fluxes showed large temporal and spatial dynamics. The CO 2 fluxes showed a significantly negative correlation with daily total radiation (DTR) and a weakly negative correlation with air temperature and water temperature, indicating that sunlight intensity controlled the magnitude of CO 2 fluxes from the open lakes. The CH 4 fluxes significantly correlated with local air temperature, water table and total dissolved solids (TDS), indicating that they were the predominant factors influencing CH 4 fluxes. Summertime CO 2 budgets in the littoral zones of Lake Mochou and Lake Tuanjie were estimated to be -152.9 gCO 2 m -2 and -79.7 gCO 2 m -2, respectively, and net CH 4 emissions were estimated to be 312.3 mgCH 4 m -2 and 237.2 mgCH 4 m -2, respectively. Our results show that shallow, open, alga-rich lakes might be strong summertime CO 2 absorbers and small CH 4 emitters during the open water in coastal Antarctica.

  4. Littoral assessment of mine burial signatures (LAMBS): buried landmine/background spectral-signature analyses

    NASA Astrophysics Data System (ADS)

    Kenton, Arthur C.; Geci, Duane M.; Ray, Kristofer J.; Thomas, Clayton M.; Salisbury, John W.; Mars, John C.; Crowley, James K.; Witherspoon, Ned H.; Holloway, John H., Jr.

    2004-09-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 μm) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites. We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

  5. Between tide and wave marks: a unifying model of physical zonation on littoral shores

    PubMed Central

    Bird, Christopher E.; Franklin, Erik C.; Smith, Celia M.

    2013-01-01

    The effects of tides on littoral marine habitats are so ubiquitous that shorelines are commonly described as ‘intertidal’, whereas waves are considered a secondary factor that simply modifies the intertidal habitat. However mean significant wave height exceeds tidal range at many locations worldwide. Here we construct a simple sinusoidal model of coastal water level based on both tidal range and wave height. From the patterns of emergence and submergence predicted by the model, we derive four vertical shoreline benchmarks which bracket up to three novel, spatially distinct, and physically defined zones. The (1) emergent tidal zone is characterized by tidally driven emergence in air; the (2) wave zone is characterized by constant (not periodic) wave wash; and the (3) submergent tidal zone is characterized by tidally driven submergence. The decoupling of tidally driven emergence and submergence made possible by wave action is a critical prediction of the model. On wave-dominated shores (wave height ≫ tidal range), all three zones are predicted to exist separately, but on tide-dominated shores (tidal range ≫ wave height) the wave zone is absent and the emergent and submergent tidal zones overlap substantially, forming the traditional “intertidal zone”. We conclude by incorporating time and space in the model to illustrate variability in the physical conditions and zonation on littoral shores. The wave:tide physical zonation model is a unifying framework that can facilitate our understanding of physical conditions on littoral shores whether tropical or temperate, marine or lentic. PMID:24109544

  6. Trophic niche partitioning of littoral fish species from the rocky intertidal of Helgoland, Germany

    NASA Astrophysics Data System (ADS)

    Hielscher, N. N.; Malzahn, A. M.; Diekmann, R.; Aberle, N.

    2015-12-01

    During a 3-year field study, interspecific and interannual differences in the trophic ecology of littoral fish species were investigated in the rocky intertidal of Helgoland island (North Sea). We investigated trophic niche partitioning of common coexisting littoral fish species based on a multi-tracer approach using stable isotope and fatty acids in order to show differences and similarities in resource use and feeding modes. The results of the dual-tracer approach showed clear trophic niche partitioning of the five target fish species, the goldsinny wrasse Ctenolabrus rupestris, the sand goby Pomatoschistus minutus, the painted goby Pomatoschistus pictus, the short-spined sea scorpion Myoxocephalus scorpius and the long-spined sea scorpion Taurulus bubalis. Both stable isotopes and fatty acids showed distinct differences in the trophic ecology of the studied fish species. However, the combined use of the two techniques added an additional resolution on the interannual scale. The sand goby P. minutus showed the largest trophic plasticity with a pronounced variability between years. The present data analysis provides valuable information on trophic niche partitioning of fish species in the littoral zones of Helgoland and on complex benthic food webs in general.

  7. Littoral Assessment of Mine Burial Signatures (LAMBS) buried land mine/background spectral signature analyses

    USGS Publications Warehouse

    Kenton, A.C.; Geci, D.M.; Ray, K.J.; Thomas, C.M.; Salisbury, J.W.; Mars, J.C.; Crowley, J.K.; Witherspoon, N.H.; Holloway, J.H., Jr.

    2004-01-01

    The objective of the Office of Naval Research (ONR) Rapid Overt Reconnaissance (ROR) program and the Airborne Littoral Reconnaissance Technologies (ALRT) project's LAMBS effort is to determine if electro-optical spectral discriminants exist that are useful for the detection of land mines in littoral regions. Statistically significant buried mine overburden and background signature data were collected over a wide spectral range (0.35 to 14 ??m) to identify robust spectral features that might serve as discriminants for new airborne sensor concepts. LAMBS has expanded previously collected databases to littoral areas - primarily dry and wet sandy soils - where tidal, surf, and wind conditions can severely modify spectral signatures. At AeroSense 2003, we reported completion of three buried mine collections at an inland bay, Atlantic and Gulf of Mexico beach sites.1 We now report LAMBS spectral database analyses results using metrics which characterize the detection performance of general types of spectral detection algorithms. These metrics include mean contrast, spectral signal-to-clutter, covariance, information content, and spectral matched filter analyses. Detection performance of the buried land mines was analyzed with regard to burial age, background type, and environmental conditions. These analyses considered features observed due to particle size differences, surface roughness, surface moisture, and compositional differences.

  8. Monitoring coastal evolution and associated littoral hazards of French Guiana shoreline with radar images

    NASA Astrophysics Data System (ADS)

    Trebossen, Hervé; Deffontaines, Benoît; Classeau, Nicolas; Kouame, Jacob; Rudant, Jean-Paul

    2005-09-01

    This paper aims at illustrating different case examples of monitoring active coastal evolutions using remote sensing synthetic aperture radar images (ERS 1-2 and Envisat) in humid tropical areas. Effectively, the radar satellite images may be acquired under most climate conditions, especially in cloudy tropical areas. As case examples, we studied herein French Guiana shoreline and its fast evolution under the combined influences of sea currents, sediments and swells. We focused on two aspects of French Guiana littoral evolution: (1) sedimentation and erosion processes linked to mud banks displacements around Kourou City, and (2) around Iracoubo village. Lastly, we compared this short-term sedimentation balance with long-term data showing the discrepancies of short- and long-term littoral evolutions on whole French Guiana. To conclude, this work demonstrates the importance of SAR imagery to provide high-quality and high-frequency update geographic information for coastal management and littoral hazards especially in such tropical humid and cloudy areas. To cite this article: H. Trebossen et al., C. R. Geoscience 337 (2005).

  9. Impacts to Dungeness Crab from the Southwest Washington Littoral Drift Restoration Project

    SciTech Connect

    Williams, Greg D.; Kohn, Nancy P.; Pearson, Walter H.; Skalski, J R.

    2005-11-09

    The Benson Beach littoral drift restoration project is a demonstration project that will replenish sand on Benson Beach, the public beach north of the North Jetty at the mouth of the Columbia River (MCR), using material dredged from the river during normal maintenance dredging of the navigational channel. A U.S. Army Corps of Engineers (Corps) proposal involves pumping the material from a sump area on the south side of the jetty to Benson Beach using a cutter suction dredge, also known as a pipeline dredge. If this one-time demonstration project proves feasible and successful, up to a million cubic yards of sediment could be used to replenish the outer coast littoral drift system in successive years by the same process. The primary goal of this study was to assess the potential risk of impacts to Dungeness crab from the proposed Benson Beach littoral drift restoration process of using the cutter suction dredge to move sediment from the proposed sump area on one side of the North Jetty to the beach on the other side of the jetty. Because there are no direct measurements of crab entrainment by pipeline dredge operating outside of the lower Columbia River navigation channel, dredge impacts for the proposed demonstration project were estimated using a modification of the dredge impact model (DIM) of Armstrong et al. (1987). The model estimates adult equivalent loss (AEL) of crabs using crab population density from trawl surveys, dredge project information (gear type, season, location, volume), and an entrainment function relating crab population density to entrainment by the dredge. The input used in applying the DIM to the Benson Beach littoral drift restoration included the specific dredging scenario provided by the Corps, existing data on crab density in previously proposed sump areas, and a series of entrainment functions. A total of fourteen scenarios were modeled and the outcomes compared with six reference scenarios intended to represent realistic to worst cases

  10. Polyketides from the littoral plant associated fungus Pseudallescheria boydii.

    PubMed

    Chang, Ya-Chih; Deng, Tzu-Shing; Pang, Ka-Lai; Hsiao, Che-Jen; Chen, Yi-Ying; Tang, Shye-Jye; Lee, Tzong-Huei

    2013-09-27

    Four previously unreported chemical entities, boydone A (1), boydone B (2), botryorhodine F (3), and botryorhodine G (4), along with five known compounds, fusidilactone A (5), (R)-(-)-mevalonolactone (6), (R)-(-)-lactic acid (7), ovalicin (8), and botryorhodine C (9), were isolated from the ethyl acetate extracts of the fermented broths of the fungal strain Pseudallescheria boydii NTOU2362. The structures of 1-9 were characterized on the basis of their spectroscopic data analyses. The absolute configurations of 1 and 2 were established by comparison with the literature and the modified Mosher's method. The growth inhibitory activities of 1-9 against the A549 non-small-cell lung cancer cell line were evaluated, and 2 and 8 exhibited moderate to potent bioactivities with GI₅₀ values of 41.3 and 4.1 μM, respectively, in comparison with fluorouracil (GI₅₀ = 3.6 μM). PMID:23964677

  11. Zonation and spatial distribution of littoral fish communities from the southwestern Finnish coast (Archipelago and Bothnian Sea, Northern Baltic Sea)

    NASA Astrophysics Data System (ADS)

    Vahteri, Petri; O'Brien, Kevin; Vuorinen, Ilppo

    2009-03-01

    The aim of our study was to test whether the distribution of littoral fish assemblages would reflect both their immediate environment with reference to local underwater vegetation, including larger scale geographic archipelagial zonation. A total of 62 locations were sampled using beach seine and underwater video along the southwestern Finnish coastline in summer 2001. At all locations, water temperature, water transparency and benthic vegetation patterns (depth ranges of plant species or taxa) were recorded. Using correspondence analysis, our results showed a clear division of the Archipelago Sea into three separate zones based on littoral fish species assemblages. Overall, fish assemblages formed three distinct site groups, being dominated by pike and cyprinids, by percids and gobies, or by gasterosteids, and showed clear inner, middle and outer archipelago zones respectively, within the study area. Our results suggest that while vegetation in the study sites was diverse, it failed to express the zonation reflected by the littoral fish assemblages, which showed a definite zonation pattern which broadly reflected previous reports using both physical and biological parameters. We interpret our results to show that littoral vegetation is better in expressing small-scale differences between study sites, while littoral fish communities are more robust in detecting changes over a larger geographical scale.

  12. Using catenas for GIS-based mapping of NW Mediterranean littoral habitats

    NASA Astrophysics Data System (ADS)

    Mariani, Simone; Cefalì, Maria Elena; Terradas, Marc; Chappuis, Eglantine; Ballesteros, Enric

    2014-06-01

    Studies aimed at describing habitats and mapping their distributions are pivotal to implementing management plans and to effectively guide conservation measures. We developed a novel approach of data collection and entry (CAT-LIT) to establish a detailed cartography of the littoral habitats found along the Catalan coast (Spain). Field data were recorded using coded, two-digit hierarchical lists (e.g. Aa, Ab, etc.) of horizons found at each point along the coast, called catenas. The horizons were either dominated by species (on the rocky bottoms) or sediment types (on the beaches) and corresponded to LPRE, EUNIS and CORINE habitats. Catenas were transferred into a database and calculations about the extent of bottom types, habitats, and catenas themselves along the coast were carried out with GIS tools. In addition, habitat link richness was calculated and represented using network analysis programs. The application of CAT-LIT to the Catalan coast showed that the habitats dominated by the lichen Verrucaria amphibia and the flattened barnacle Euraphia depressa and those dominated by the barnacle Chthamalus spp. were almost ubiquitous. Those dominated by the red alga Corallina elongata, the mussel Mytilus galloprovincialis and the red alga Rissoella verruculosa were also common. Because of the frequency of their connections, those habitats formed a huge hub of links in the networks. By using catenas, the habitats can be viewed using GIS based programs keeping the catena as the main informational and ecological unit. The catenas allow maximum compactness when vertically distributed habitats are to be shown on a 2D map. The complete cartography and dataset on the spatial distribution of the littoral habitats from Catalonia is valuable for coastal management and conservation to study changes in the habitat distribution and relate such changes to anthropogenic pressures. Furthermore, the CAT-LIT can be easily adapted to shores of other seas and oceans to obtain accurate

  13. Nitrous oxide fluxes from the littoral zone of a lake on the Qinghai-Tibetan Plateau.

    PubMed

    Chen, Huai; Wang, Meng; Wu, Ning; Wang, Yanfen; Zhu, Dan; Gao, Yongheng; Peng, Changhui

    2011-11-01

    Nitrous oxide (N(2)O) fluxes were measured in six littoral mirco-zones of Lake Huahu on Qinghai-Tibetan Plateau in the peak growing season of years of 2006 and 2007. The weighted mean N(2)O flux rate was 0.08 mg N m(-2) h(-1) (ranged from -0.07 to 0.35 mg N m(-2) h(-1)). The result was relatively high in the scope of N(2)O fluxes from boreal and temperate lakes. Emergent plant zones (Hippuris vulgaris and Glyceria maxima stands) recorded the highest N(2)O flux rate (0.11 ± 0.24 and 0.08 ± 0.17 mg N m(-2) h(-1), respectively). Non-vegetated lakeshore recorded the lowest N(2)O flux (0.03 ± 0.11 mg N m(-2) h(-1)), lower than that from the floating mat zone of Carex muliensis (0.05 ± 0.18 mg N m(-2) h(-1)), the floating-leaved plant zone of Polygonum amphibium (0.07 ± 0.11 mg N m(-2) h(-1)), and the wet meadow (0.07 ± 0.15 mg N m(-2) h(-1)). Standing water depths were important factors to explain such spatial variations in N(2)O fluxes. Significant temporal variations in N(2)O fluxes were also found. Such temporal variation in N(2)O flux in the littoral zone may be dependent on the interaction of water regime and thermal conditions, instead of the latter solely. These results showed the importance of the littoral zone of lake, especially the emergent plant zone, as a hotspot of N(2)O fluxes in such grazing meadows. PMID:21327481

  14. Habitat Degradation and Seasonality Affect Physiological Stress Levels of Eulemur collaris in Littoral Forest Fragments

    PubMed Central

    Balestri, Michela; Barresi, Marta; Campera, Marco; Serra, Valentina; Ramanamanjato, Jean Baptiste; Heistermann, Michael; Donati, Giuseppe

    2014-01-01

    The littoral forest on sandy soil is among the most threatened habitats in Madagascar and, as such, it represents a hot-spot within a conservation hot-spot. Assessing the health of the resident lemur fauna is not only critical for the long-term viability of these populations, but also necessary for the future re-habilitation of this unique habitat. Since the Endangered collared brown lemur, Eulemur collaris, is the largest seed disperser of the Malagasy south-eastern littoral forest its survival in this habitat is crucial. In this study we compared fecal glucocorticoid metabolite (fGCM) levels, a measure of physiological stress and potential early indicator of population health, between groups of collared brown lemurs living in a degraded forest fragment and groups occurring in a more preserved area. For this, we analysed 279 fecal samples collected year-round from 4 groups of collared brown lemurs using a validated 11-oxoetiocholanolone enzyme immunoassay and tested if fGCM levels were influenced by reproductive stages, phenological seasons, sex, and habitat degradation. The lemurs living in the degraded forest had significantly higher fGCM levels than those living in the more preserved area. In particular, the highest fGCM levels were found during the mating season in all animals and in females during gestation in the degraded forest. Since mating and gestation are both occurring during the lean season in the littoral forest, these results likely reflect a combination of ecological and reproductive pressures. Our findings provide a clear indication that habitat degradation has additive effects to the challenges found in the natural habitat. Since increased stress hormone output may have long-term negative effects on population health and reproduction, our data emphasize the need for and may add to the development of effective conservation plans for the species. PMID:25229944

  15. Coarse fragmental material of the littoral zones on the Murmansk and Carelian coasts

    NASA Astrophysics Data System (ADS)

    Mityaev, M. V.; Gerasimova, M. V.

    2010-04-01

    A three-year study of the abrasion of coarse fragmental material on the Murmansk coast has been carried out. According to the researchers, the average rate of the abrasion of the coarse-fragmental material of granitoid composition on the Murmansk coast has been determined. It was revealed that the rate of the destruction of the blocks increases from the lower littoral zone to the upper one. The estimation of the quantity of sedimentary material coming to the sedimentation basin as a result of the abrasion of coarse-fragmental material has been carried out.

  16. Unravelling the nocturnal appearance of bogue Boops boops shoals in the anthropogenically modified shallow littoral.

    PubMed

    Mavraki, N; Georgiadis, M; Koutsikopoulos, C; Tzanatos, E

    2016-05-01

    In the present study the role of the nocturnal migration of bogue Boops boops shoals to anthropogenically modified shallow littoral locations was examined, evaluating four alternative hypotheses: (1) feeding, (2) reproduction, (3) attraction of B. boops to artificial light and (4) concealment in the darkness related to predation avoidance. All hypotheses apart from predation avoidance were rejected, as B. boops tended to concentrate in shaded locations of wider illuminated areas, a finding not only important concerning fish behaviour, but also with significant management implications. PMID:27094613

  17. Environmental assessment of the Alaskan continental shelf: reports of principal investigators. Volume 1: reactors - birds, plankton, littoral, benthos

    SciTech Connect

    Not Available

    1980-01-01

    Simulation modeling of marine bird population energetics, food consumption, and sensitivity to perturbation was performed. Shorebird dependence on Arctic: littoral habitats was studied as well as the distribution, abundance, and feeding ecology of birds associated with pack ice. A study of the population numbers and productivity of colonial seabirds is included. Plankton studies in the Bering Sea and an environmental assessment of selected habitats in the Arctic littoral system are also included. The distribution, abundance, community structure, and trophic relationships of the benthos of the Northeastern Gulf of Alaskan from Yakutat Bay to Cross Sound and the distribution, abundance, diversity, and productivity of the Western Sea benthos were studied.

  18. Discontinuities in the recent and Quaternary margino-littoral sedimentation of Benin (humid tropical zone)

    NASA Astrophysics Data System (ADS)

    Lang, J.; Oyéde, M.

    In the first part of this paper, factors involved in the present margino-littoral sedimentary dynamics are reviewed, with the ≪normal≫ biosedimentary phenomena or "background noise" on a daily and seasonal scale. The breaks in sedimentary and environmental equilibria which generate sedimentary discontinuities and major facies variations are then analyzed. Within the Quaternary sequences, beside the breaks in sedimentary and environmental equilibria which act on a daily or seasonal time-scale (e.g. hurricanes, floods), it is possible to observe slower phenomena lasting over a hundred or a thousand years (sea-level oscillations, epirogenic and neotectonical movements, palaeoclimatic changes, streams wanderings). The recent margino-littoral domain of Benin, with alternating wet and dry seasons, adding their effects to those of saline intrusions, is a very favourable environment where biosedimentary phenomena, ≪normal≫ as well as ≪exceptional≫, on various time scales, can be recorded. The aim of this paper is to recover the information "recorded" from these "recordable" biosedimentary phenomena, more or less magnified or dampened by the "recording" environment, in the Upper Quaternary sequences of Benin (peat layers, mollusc thanatocoenoses, coprolites, facies variations, clays and heavy-mineral assemblages). These phenomena may appear either as short-lived events ( "crises") or as critical events such as palaeogeographical events (40 000 to 39 000 years B.P., 6000 to 5000 years B.P.) or palaeoclimatic events (18 000 years B.P.).

  19. Influence of nutrient additions on cadmium bioaccumulation by aquatic invertebrates in littoral enclosures

    SciTech Connect

    Currie, R.S.; Muir, D.C.G.; Fairchild, W.L.; Holoka, M.H.; Hecky, R.E.

    1998-12-01

    Cadmium distribution and bioaccumulation were examined over a 2-year period (1991--1992) in two nutrient-enriched and two control littoral enclosures and in the littoral zone in Lake 382 (L382). Lake 382, a small oligotrophic lake, is located within the Experimental Lakes Area in northwestern Ontario, Canada, and received experimental Cd additions from 1987 to 1992. In the second year of this study, chlorophyll a and suspended C concentrations in the nutrient-enriched enclosures increased by 6.6 and 3.4 times, respectively, compared to the controls. As a result of increased particulate produced by the nutrient additions, Cd concentrations in water from the nutrient-enriched enclosures were higher compared to the controls. Estimated Cd/C concentrations in water were lower in the nutrient-enriched enclosures relative to the controls because of higher particle concentrations. Effects on Cd bioaccumulation were limited even though mesotrophic to eutrophic conditions were reached in the nutrient-enriched enclosures had consistently higher Cd concentrations compared to the controls, but significant differences were not detected. Enhanced accumulation of Cd-rich particulate matter by these organisms may account for this trend. Mussels and crayfish accumulated significantly more Cd when exposed in the lake compared to the enclosures. This observation is due to elevated Cd water concentrations in the lake compared to the enclosures because of continued Cd additions to the lake. These results suggest that the water route of exposure is an important pathway for Cd accumulation by these organisms.

  20. Spatial variation in the littoral vertebrate community of a reservoir relative to physical and biological gradients

    PubMed Central

    Soski, Jessica J.; Roosenburg, Willem M.

    2014-01-01

    Reservoirs possess gradients in conditions and resources along their long (deep-shallow) axis, but the response of littoral vertebrates (fish and turtles) to these gradients is poorly understood. We have quantified the littoral vertebrate communities throughout a small reservoir in Southeastern Ohio during July and August using traps, and related community composition to environmental variables using NMDS ordination. Ordination revealed that fish and turtles were broadly separated in ordination space, and three distinctly different environmental gradients were significantly associated with the underlying observed species abundances. Observed turtle abundance was explained by measurements of bathymetry, turbidity, and benthic resources, but none of these environmental variables were a reliable predictor of observed fish abundance. Temperature was a poor predictor of observed abundance for both fish and turtles independently, but when fish and turtles were considered together, it became apparent that there were cold areas of the reservoir where observed fish and turtle abundances were different than in other areas of the reservoir. These results suggest that the predictor (environmental) variables we used were appropriate for investigating turtle ecology in reservoirs, but that observed fish abundance is mediated by factors that were not modeled. The efficacy of using traps, the ecological implications of considering fish and turtles together as sympatric and potentially competing species, and directions for future study are discussed. PMID:25538870

  1. Use and occupation of Olinda littoral (NE, Brazil): guidelines for an integrated coastal management.

    PubMed

    Pereira, Luci Cajueiro Carneiro; Jiménez, José A; Medeiros, Carmen; da Costa, Rauquírio Marinho

    2007-08-01

    Located on the northeast Brazilian coast, Olinda is one of UNESCO's World Heritage Sites, which is economically dependent on tourism, commerce, industry, and the informal economy. Despite its environmental and socioeconomic importance, the city of Olinda (understanding the coast as part of it) has suffered several environmental and human disturbances over the last decades. This work describes the environmental and social status of Olinda's beaches and makes recommendations concerning the development of an Integrated Coastal Management Plan for this coastal zone of the Brazilian littoral. The methodology adopted in this study is based on field campaigns (social, physical, chemical, and biological data collection), local observations, and the collection of sea contention building project data from city hall. The results showed that along the seven studied beaches, the main problems were related to the: (i) building of coastal protections, (ii) inefficient sewage disposal systems, (iii) inefficient urban management, and (iv) natural events (equinoctial spring tides and precipitation/evaporation rates). Casa Caiada beach showed the best hydrologic conditions as a consequence of its morphology and it presents facilities that attract housing and recreation investments (by private and public sectors) valuing and improving local use conditions. The obtained data showed that the studied beaches need an urgent action plan to minimize the environmental degradation of Olinda's littoral and to promote sustainable development of the local coastal environments. PMID:17602259

  2. Population dynamics of shrimps in littoral marine waters of the Mekong Delta, south of Viet Nam.

    PubMed

    Dinh, T D; Moreau, J; Van, M V; Phuong, N T; Toan, V T

    2010-07-15

    The population dynamics of eight commercial species of shrimp (Haliporoides sibogae, Harpiosquilla harpax, Metapenaeus affinis, Metapenaeus brevicornis, Metapenaeus tenuipes, Parapenaeopsis cultrirostris, Parapenaeopsis gracillima and Parapenaeus maxilipedo) distributed in littoral marine zone of the Mekong Delta were investigated. Length-based stock assessment using FiSAT II software package was used to assess the growth and mortality parameters: Asymptotic size (L8), growth coefficient (K), total (Z) and natural (M) mortality, exploitation rate (E), recruitment pattern, current probability of capture and selectivity of fishing gears. Yield-per-recruit analyses were carried out showing different levels of the exploitation. Results showed that the maximum sustainable yield would be reached for an exploitation rate higher than the current one for each population. However, the size of first capture should be increased for every population. The findings indicated that the current exploitations of shrimp populations distributed in littoral marine zone of the Mekong Delta are under exploitation level for maximum sustainable yield; however, all the shrimp populations are subject to growth over-exploitation. PMID:21848060

  3. Littoral microcrustacean (Cladocera and Copepoda) indicators of acidification in Canadian Shield lakes.

    PubMed

    Walseng, Bjørn; Yan, Norman D; Schartau, Ann Kristin

    2003-04-01

    We identify littoral microcrustacean indicators of acidification in 2 surveys of Canadian Shield lakes conducted 10 years apart. We found a total of 90 cladoceran and copepod species with richness increasing severalfold from acidic to nonacidic lakes. The fauna of the nonacidic lakes differed between the surveys. The 1987 survey employed activity traps, and caught more littoral taxa than the more recent, net-haul-based survey. Similar faunas were identified in the acidified lakes in both surveys, and several good indicator species were identified. For example, Acanthocycops vernalis was restricted to lakes with pH < 6. Sinobosmina sp. was very common but only in lakes with pH > 4.8. Tropocyclops extensus, Mesocyclops edax, and Sida crystallina were commonly found but only at pH > 5, and Chydorus faviformis only at pH > 5.9. These indicators showed promise in gauging the early stages of recovery from acidification in 3 lakes that were included in both surveys. PMID:12839197

  4. Littoral and Coastal Management in Supporting Maritime Security for Realizing Indonesia as World Maritime Axis

    NASA Astrophysics Data System (ADS)

    Brotosusilo, Agus; Wayan Agus Apriana, I.; Agung Satria, Afrizal; Jokopitoyo, Trisasono

    2016-02-01

    The Indonesian under President Joko Widodo has new goal to make Indonesia as the world maritime axis. This is supported by the geographic of Indonesia as the largest archipelagic country where the sea is two-thirds wide among the whole spacious. Indonesia is the world largest archipelagic state. More than two-third of its territory consist of seas. The ecosystem of littoral and coastal has correlative relationship with country development. There is no doubt of physically facts that Indonesian littoral and coastal with total wide of 5.8 million km2 is rich with various natural resources. Therefore, the condition of Indonesia with its world second longest coastline has several comparative advantages. Not only the country has an abundant natural resources, but it also blessed by demographic bonus advantage. The population of Indonesian is the fifth largest in the world which approximately 220 million people and approximately 60 percent among them live at coastal areas. The people in coastal area relies their live from its surrounding natural resource. Hence, most of their life and daily activity is related with the presence of natural resources. The dealing of conflict potential and attention to maritime security are important to be studied as a reference in preparing and facing the government policies that will lead to the development of maritime.

  5. An iso-deviant approach for acoustic computations using efficient adaptive gridder for littoral environments

    NASA Astrophysics Data System (ADS)

    Rike, Erik R.; Delbalzo, Donald R.

    2005-04-01

    Transmission Loss (TL) computations in littoral areas require a dense spatial and azimuthal grid to achieve acceptable accuracy and detail. The computational cost of accurate predictions led to a new concept, OGRES (Objective Grid/Radials using Environmentally-sensitive Selection), which produces sparse, irregular acoustic grids, with controlled accuracy. Recent work to further increase accuracy and efficiency with better metrics and interpolation led to EAGLE (Efficient Adaptive Gridder for Littoral Environments). On each iteration, EAGLE produces grids with approximately constant spatial uncertainty (hence, iso-deviance), yielding predictions with ever-increasing resolution and accuracy. The EAGLE point-selection mechanism is tested using the predictive error metric and 1-D synthetic data-sets created from combinations of simple signal functions (e.g., polynomials, sines, cosines, exponentials), along with white and chromatic noise. The speed, efficiency, fidelity, and iso-deviance of EAGLE are determined for each combination of signal, noise, and interpolator. The results show significant efficiency enhancements compared to uniform grids of the same accuracy. [Work sponsored by ONR under the LADC project.

  6. Iso-deviant 2D gridding with efficient adaptive gridder for littoral environments (EAGLE)

    NASA Astrophysics Data System (ADS)

    Rike, Erik R.; Delbalzo, Donald R.

    2005-09-01

    Transmission loss (TL) computations in littoral areas require a dense spatial and azimuthal grid to achieve acceptable accuracy and detail. The computational cost of accurate predictions led to a new concept, OGRES (Objective Grid/Radials using Environmentally-sensitive Selection), which produces sparse, irregular acoustic grids, with controlled accuracy. Recent work to further increase accuracy and efficiency with better metrics and interpolation led to EAGLE (Efficient Adaptive Gridder for Littoral Environments). On each iteration, EAGLE produces grids with approximately constant spatial uncertainty (hence, iso-deviance), yielding predictions with ever-increasing resolution and accuracy. The EAGLE point-selection mechanism is tested using the predictive error metric and 2D synthetic data sets created from combinations of simple signal functions (e.g., polynomials, sines, cosines, exponentials), along with white and chromatic noise. The speed, efficiency, fidelity, and iso-deviance of EAGLE are determined for each combination of signal, noise, and interpolator. The results show significant efficiency enhancements compared to uniform grids of the same accuracy. [Work sponsored by NAVAIR.

  7. Littoral hydrovolcanic explosions: a case study of lava seawater interaction at Kilauea Volcano

    NASA Astrophysics Data System (ADS)

    Mattox, Tari N.; Mangan, Margaret T.

    1997-01-01

    A variety of hydrovolcanic explosions may occur as basaltic lava flows into the ocean. Observations and measurements were made during a two-year span of unusually explosive littoral activity as tube-fed pahoehoe from Kilauea Volcano inundated the southeast coastline of the island of Hawai`i. Our observations suggest that explosive interactions require high entrance fluxes (≥4 m 3/s) and are most often initiated by collapse of a developing lava delta. Two types of interactions were observed. "Open mixing" of lava and seawater occurred when delta collapse exposed the mouth of a severed lava tube or incandescent fault scarp to wave action. The ensuing explosions produced unconsolidated deposits of glassy lava fragments or lithic debris. Interactions under "confined mixing" conditions occurred when a lava tube situated at or below sea level fractured. Explosions ruptured the roof of the tube and produced circular mounds of welded spatter. We estimate a water/rock mass ratio of 0.15 for the most common type of littoral explosion and a kinetic energy release of 0.07-1.3 kJ/kg for the range of events witnessed.

  8. Dominant species of the gastropod fauna from the littoral region in Lake Ohrid of R. Macedonia.

    PubMed

    Smiljkov, S; Budzakoska-Gjoreska, B; Sapkarev, J; Trajanovski, S

    2007-07-01

    The class of Gastropoda is one of the Lake Ohrid' macrozoobenthic groups, which characterize highest level of endemism. Since the first published references until now, studying the Lake Ohrid's snail fauna represents huge scientific challenge for many malacologists from the world. The high percent of endemic as well as relic forms among the lake's gastropods could be explained by the processes of intralacustric speciation during the history and evolution of this aquatic ecosystem. These processes no doubt have been enabled by the complexity and stability of the Lake's basin. This work represents the results of the dominant species, from both qualitative and quantitative sense of the gastropod fauna from 19 investigated littoral localities of Lake Ohrid. The results from the investigations on gastropod fauna has shown that following species: Chilopyrgula sturanyi, Radix relicta and Valvata stenotrema quailtatively predominates in the samples from the littoral region of the Macedonian part of Lake Ohrid. The quantitative analyses (according to their presence on m2), has shown that the following species predominate: Chilopyrgula sturanyi (6879 No x m2), Theodoxus fluviatilis dalmaticus (6412 No x m2), Pyrgohydrobia grochmalickii (5504 No x m2) and Valvata stenotrema (5009 No x m2). PMID:17921924

  9. Ecological speciation in postglacial European whitefish: rapid adaptive radiations into the littoral, pelagic, and profundal lake habitats.

    PubMed

    Præbel, Kim; Knudsen, Rune; Siwertsson, Anna; Karhunen, Markku; Kahilainen, Kimmo K; Ovaskainen, Otso; Ostbye, Kjartan; Peruzzi, Stefano; Fevolden, Svein-Erik; Amundsen, Per-Arne

    2013-12-01

    Understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. Postglacial fishes are excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete environments with variation in available niches. Here, we combine data of niche utilization, trophic morphology, and 17 microsatellite loci to investigate the diversification process of three sympatric European whitefish morphs from three northern Fennoscandian lakes. The morphological divergence in the gill raker number among the whitefish morphs was related to the utilization of different trophic niches and was associated with reproductive isolation within and across lakes. The intralacustrine comparison of whitefish morphs showed that these systems represent two levels of adaptive divergence: (1) a consistent littoral-pelagic resource axis; and (2) a more variable littoral-profundal resource axis. The results also indicate that the profundal whitefish morph has diverged repeatedly from the ancestral littoral whitefish morph in sympatry in two different watercourses. In contrast, all the analyses performed revealed clustering of the pelagic whitefish morphs across lakes suggesting parallel postglacial immigration with the littoral whitefish morph into each lake. Finally, the analyses strongly suggested that the trophic adaptive trait, number of gill rakers, was under diversifying selection in the different whitefish morphs. Together, the results support a complex evolutionary scenario where ecological speciation acts, but where both allopatric (colonization history) and sympatric (within watercourse divergence) processes are involved. PMID:24455129

  10. The littoral zone in the Three Gorges Reservoir, China: challenges and opportunities.

    PubMed

    Yuan, Xing-zhong; Zhang, Yue-wei; Liu, Hong; Xiong, Sen; Li, Bo; Deng, Wei

    2013-10-01

    For flood control purpose, the water level of the Three Gorges Reservoir (TGR) varies significantly. The annual reservoir surface elevation amplitude is about 30 m behind the dam. Filling of the reservoir has created about 349 km(2) of newly flooded riparian zone. The average flooding period lasts for more than 6 months, from mid-October to late April. The dam and its associated reservoir provide flood control, power generation, and navigation, but there are also many environmental challenges. The littoral zone is the important part of the TGR, once its eco-health and stability are damaged,which will directly endanger the ecological safety of the whole reservoir area and even the Yangtze River Basin. So, understanding the great ecological opportunities which are hidden in littoral zone of TGR (LZTGR) and putting forward approaches to solve the environmental problems are very important. LZTGR involves a wide field of problems, such as the landslides, potential water pollution, soil erosion, biodiversity loss, land cover changes, and other issues. The Three Gorges dam (TGD) is a major trigger of environmental change in the Yangtze River. The landslides, water quality, soil erosion, loss of biodiversity, dam operation, and challenge for land use are closely interrelated across spatial and temporal scales. Therefore, the ecological and environmental impacts caused by TGD are necessarily complex and uncertain. LZTGR is not only a great environmental challenge but also an ecological opportunity for us. In fact, LZTGR is an important structural unit of TGR ecosystem and has special ecosystem services function. Vegetation growing in LZTGR is therefore a valuable resource due to accumulation of carbon and nutrients. Everyone thinks that the ecological approach to the problem is needed. If properly designed, dike-pond systems, littoral woods systems, and re-created waterfowl habitats will have the capacity to capture nutrients from uplands and obstruct soil erosion

  11. Effect of metals on Daphnia magna and cladocerans representatives of the Argentinean fluvial littoral.

    PubMed

    Luciana, Regaldo; Reno, Ulises; Gervasio, Susana; Horacio, Troiani; Gagneten, Ana María

    2014-07-01

    Chronic toxicity tests were conducted to assess the effect of Cu, Cr and Pb on Moinodaphnia macleayi and Ceriodaphnia dubia -two cladoceran species from the Argentinian Fluvial Littoral Zone (AFLZ)- and Daphnia magna -an holarctic species-. The specimens were exposed to three concentrations of each metal. As endpoints, the number of living and dead organisms, molts, neonates released, and the age of first reproduction were recorded. Chronic assays showed that Cu significantly affected the analyzed life history traits in the three species. The lowest Pb and Cr concentrations did not affect survival, molting or fecundity in D. magna. Conversely, in M. macleayi and C. dubia, survival, molting and fecundity showed highly significant differences in all the concentrations tested compared to control assay. The present study stresses the importance of using biological parameters as bioindicators, as well as the study species from the Southern Hemisphere to assess metal pollution. PMID:25004754

  12. Oesophageal Cancer Studies in the Caspian Littoral of Iran: The Caspian Cancer Registry

    PubMed Central

    Mahboubi, E.; Kmet, J.; Cook, P. J.; Day, N. E.; Ghadirian, P.; Salmasizadeh, S.

    1973-01-01

    The results of the first 3 years of cancer registration on the Caspian Littoral are described. The main finding, confirming previous reports, is a very large variation within the region of the incidence of oesophageal cancer. Possible sources of bias are considered and shown to contribute little to the pattern of incidence. Among women there is a thirty-fold variation in the incidence across the regions; among men a ten-fold variation. In the north-east of the region the tumour is at least as common in women as in men, and is more common than almost any tumour anywhere in the world. Among other tumours, stomach cancer has a strikingly uniform incidence by comparison; breast cancer shows an incidence gradient of opposite slope. PMID:4743904

  13. The FRALIT teledetection program, using the ERTS-A satellite, for the oceanic littoral of France

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator); Cazabat, C.; Demathieu, P.; Dupuis, J.

    1972-01-01

    There are no author-identified significant results in this report. The French Atlantic Littoral program, utilizing data from the ERTS-1 satellite, is considered. It involves teledetection of the French shoreline along the Atlantic Ocean and English Channel. A description is given of the ERTS-1 orbit and the satellite itself, including the attitude control system, and the data acquisition and transmission equipment. The geographic extent of the area covered by the program is delineated and the subjects studied are enumerated. These include the geomorphology, pedology, hydrology, and vegetation of the maritime marshes; sedimentology, morphology, and hydrology of the intertidal zones; and transport of material in suspension to the mouths of the Seine, the Loire, and the Gironde as a part of the coastal waters study.

  14. Sediment fluxes and the littoral drift along northeast Andhra Pradesh Coast, India: estimation by remote sensing.

    PubMed

    Kunte, Pravin D; Alagarsamy, R; Hursthouse, A S

    2013-06-01

    The littoral drift regime along the northeastern coast of India was investigated by analyzing coastal drift indicators and shoreline changes based on multitemporal satellite images. The study of offshore turbidity patterns and quantitative estimation of suspended sediments was undertaken to understand the magnitude and direction of movement of sediment fluxes. The study revealed that: (1) the character of coastal landforms and sedimentation processes indicate that the sediment transport is bidirectional and monsoon dependent; (2) multidate, multitemporal analysis of satellite images helps to show the nature of sediment transport along the coast. The dominant net sediment transport is in a NE direction along the eastern coast of India. Finally, this assessment demonstrates the potential of remote sensing technology in understanding the coastal morphometric changes, long-term sediment transport, shoreline changes, and offshore turbidity distribution pattern and the implications for the transport of sediment-associated pollutants. PMID:23064851

  15. Dioctophyme renale in Vulpes vulpes from the Caspian Sea littoral of Iran

    PubMed Central

    HAJIALILO, Elham; MOBEDI, Iraj; MASOUD, Jafar; HASANPOUR, Hamid; MOWLAVI, Gholamreza

    2015-01-01

    During a long term of road survey for detection of the zoonotic helminthes in carnivores, a male Vulpes vulpes was naturally found infected by Dioctophyme renale in Caspian Sea littoral in Iran. Since the parasite transmission usually occurs through consumption of fish and other accidental food items, investigation of the worm amongst fish-eating animals in the areas with potential circulation of the helminth life cycle, has been regarded as a public health importance so far. Concerning the rout of parasite transmission to humans, different epidemiological aspects should be studied in the country. Present paper describes a destructive lesion of the kidney in the fox due to D. renale after almost a decade of monitoring for the parasite reservoirs in the region. PMID:26284212

  16. Low-cost acoustic sensors for littoral anti-submarine warfare (ASW)

    NASA Astrophysics Data System (ADS)

    Towle, Jonathan P.; Herold, David; Johnson, Ryan; Vincent, Harold

    2007-04-01

    Detecting modern diesel-electric submarines operating on batteries in littoral waters is very difficult using traditional sonar technology due in large part to the noisy and reverberant acoustic environment. To address this issue, SI2 Technologies Inc. (SI2) has developed a small, low cost, short range, dual mode acoustic sensor. The sensors can be deployed in large numbers (hundreds or thousands) to provide a high density sensor field depending upon the application of interest. SI2's low cost sensors have a short detection range and therefore are far less susceptible to multi-path reverberations and other acoustic artifacts. Simulation results will be presented showing that high probabilities of detection (P D) can be achieved with low false alarm rates (FAR) using a field of a few hundred of these low cost sensors.

  17. Guide to the littoral zone vascular flora of Carolina bay lakes (U.S.A.)

    PubMed Central

    Howell, Nathan; Braham, Richard R

    2016-01-01

    Abstract Background Carolina bays are elliptic, directionally aligned basins of disputed origin that occur on the Atlantic Coastal Plain from the Delmarva Peninsula to southern Georgia. In southeastern North Carolina, several large, natural, lacustrine systems (i.e., Carolina bay lakes) exist within the geomorphological features known as Carolina bays. Within the current distribution of Carolina bays, Bladen and Columbus counties (North Carolina) contain the only known examples of Carolina bay lakes. The Carolina bay lakes can be split into two major divisions, the “Bladen Lakes Group” which is characterized as being relatively unproductive (dystrophic – oligotrophic), and Lake Waccamaw, which stands alone in Columbus County and is known for its high productivity and species richness. Although there have been several studies conducted on these unique lentic systems, none have documented the flora comprehensively. New information Over the 2013−2014 growing seasons, the littoral zone flora of Carolina bay lakes was surveyed and vouchered. Literature reviews and herbarium crawls complemented this fieldwork to produce an inventory of the vascular plant species. This survey detected 205 taxa (species/subspecies and varieties) in 136 genera and 80 vascular plant families. Thirty-one species (15.2%) are of conservation concern. Lake Waccamaw exhibited the highest species richness with 145 catalogued taxa and 26 species of conservation concern. Across all sites, the Cyperaceae (25 spp.), Poaceae (21 spp.), Asteraceae (13 spp.), Ericaceae (8 spp.), Juncaceae (8 spp.), and Lentibulariaceae (6 spp.) were the six most species-rich vascular plant families encountered. A guide to the littoral zone flora of Carolina bay lakes is presented herein, including dichotomous keys, species accounts (including abundance, habitat, phenology, and exsiccatae), as well as images of living species and vouchered specimens. PMID:27350764

  18. N2O fluxes from the littoral zone of a Chinese reservoir

    NASA Astrophysics Data System (ADS)

    Yang, M.; Geng, X. M.; Grace, J.; Jia, Y. F.; Liu, Y. Z.; Jiao, S. W.; Shi, L. L.; Lu, C.; Zhou, Y.; Lei, G. C.

    2015-08-01

    There have been few studies of greenhouse gas emissions from reservoirs, despite the remarkable growth in the number of reservoirs in developing countries. We report a case study that focuses on the littoral zone of a major Chinese reservoir, where we established measurements of N2O fluxes using the static chamber technique at five different water levels (deep water, shallow water, seasonally flooded, control for seasonally flooded, and non-flooded). The "control for seasonal flooded" had similar vegetation to the "seasonally flooded" but was not actually flooded as it was on a higher piece of land. Seasonal, diurnal and spatial variations of N2O flux and environmental factors were monitored throughout the growing season which included a flood event during summer rains. The N2O flux ranged from -136.6 to 381.8 μg m-2 h-1 averaging 6.8 μg m-2 h-1. Seasonal and spatial variation was significant but diurnal variation was not. Non-flooded dry land emitted more N2O than flooded land, no matter whether it was permanently or seasonally flooded. Piecewise correlation was found between N2O flux, air temperature and soil nitrate concentration. Positive correlation was shown between N2O flux and dissolved oxygen in water. There were significantly higher emissions from farmland. We compared these results with our recently published study of CH4 emissions, carried out simultaneously at the same site as those in the present study. Completely different patterns between the two gases are demonstrated. We conclude that the littoral zone is a hotspot for N2O emissions in the summer, especially when the shores of the lake are used for the farming of maize. But in terms of the overall greenhouse gas budget, the fluxes of N2O are not as important as those of CH4.

  19. A quantitative evaluation of the effects of Ascophyllum harvesting on the littoral ecosystem

    NASA Astrophysics Data System (ADS)

    Boaden, P. J. S.; Dring, M. T.

    1980-03-01

    Little is known of the ecological effects of harvesting littoral algae although this is a worldwide commercial activity. In 1976 an attempt to establish harvesting in Strangford Lough, Northern Ireland, was opposed on mainly theoretical conservation grounds. The attempt began and stopped within a single small bay leaving a sharp boundary between cut and uncut areas. A subjective survey apparently confirmed the predicted loss of cryptic fauna, decline through predation and the resorting of interboulder sediment. In April 1979 the cut and uncut areas were examined in detail to determine whether any of these effects had persisted and were demonstrable scientifically. Beach and boulder transects and various other studies showed some increases in the cut area. There was significantly more Fucus, Enteromorpha and Ulva; Cirratulus (inhabiting Rhodochorton-bound sediment on boulder surfaces) had a greater biomass. Some changes in Littorina colour morphs were apparent. Sediment in the cut area was coarser and had significantly more crustacean meiofauna. Ascophyllum internodal length and lateral branching were increased but it still provided 20% less shore cover than in the uncut area. There were significant decreases in the cover of Cladophora on the sides of boulders and of Halichondria, Hymeniacodon and Balanus on undersurfaces. Indeed on the habitable underside of boulders total animal cover had been reduced by nearly two-thirds and the average number of species per boulder by one-third. It is concluded that Ascophyllum harvesting has a significant and persistent effect on shore ecology. Littoral algae are a valuable commercial asset but it is important that some fairly large intertidal areas should be left unharvested for general conservation purposes.

  20. A field proof-of-concept of tomographic slug tests in an anisotropic littoral aquifer

    NASA Astrophysics Data System (ADS)

    Paradis, Daniel; Gloaguen, Erwan; Lefebvre, René; Giroux, Bernard

    2016-05-01

    Hydraulic tomography is increasingly recognized as a characterization approach that can image pathways or barriers to flow as well as their connectivity. In this study, we assess the performance of a transient analysis of tomographic slug test head data in estimating heterogeneity in horizontal hydraulic conductivity (Kh), hydraulic conductivity anisotropy (the ratio between vertical and horizontal hydraulic conductivity - Kv/Kh) and specific storage (Ss) under actual field conditions. The tomographic experiment was carried out between two wells in a moderately heterogeneous and highly anisotropic silt and sand littoral aquifer. In this field proof-of-concept, the inversion of the two-dimensional (2D) head dataset was computed with a 2D radial flow algorithm that considers Kh, Kv/Kh, Ss and wellbore storage effects. This study demonstrated that a transient analysis of tomographic slug tests is able to capture the key features of the littoral environment of the test: the vertical profiles of Kh and Kv are indeed in agreement with those from other field and laboratory tests, and Ss values exhibit physically plausible profiles. Furthermore, the simulation of independent inter-well hydraulic tests (slug and pumping tests screened over the entire aquifer) using resolved Kh, Kv/Kh and Ss tomograms produce responses very close to field observations. This study demonstrates that the effects of fine scale heterogeneity that induces K-anisotropy at larger scales can be captured through a transient analysis of tomographic slug tests, which are very difficult to quantify otherwise with conventional hydraulic tests, thus allowing a better representation of properties controlling flow and transport in aquifer systems.

  1. Better Few than Hungry: Flexible Feeding Ecology of Collared Lemurs Eulemur collaris in Littoral Forest Fragments

    PubMed Central

    Donati, Giuseppe; Kesch, Kristina; Ndremifidy, Kelard; Schmidt, Stacey L.; Ramanamanjato, Jean-Baptiste; Borgognini-Tarli, Silvana M.; Ganzhorn, Joerg U.

    2011-01-01

    Background Frugivorous primates are known to encounter many problems to cope with habitat degradation, due to the fluctuating spatial and temporal distribution of their food resources. Since lemur communities evolved strategies to deal with periods of food scarcity, these primates are expected to be naturally adapted to fluctuating ecological conditions and to tolerate a certain degree of habitat changes. However, behavioral and ecological strategies adopted by frugivorous lemurs to survive in secondary habitats have been little investigated. Here, we compared the behavioral ecology of collared lemurs (Eulemur collaris) in a degraded fragment of littoral forest of south-east Madagascar, Mandena, with that of their conspecifics in a more intact habitat, Sainte Luce. Methodology/Principal Findings Lemur groups in Mandena and in Sainte Luce were censused in 2004/2007 and in 2000, respectively. Data were collected via instantaneous sampling on five lemur groups totaling 1,698 observation hours. The Shannon index was used to determine dietary diversity and nutritional analyses were conducted to assess food quality. All feeding trees were identified and measured, and ranging areas determined via the minimum convex polygon. In the degraded area lemurs were able to modify several aspects of their feeding strategies by decreasing group size and by increasing feeding time, ranging areas, and number of feeding trees. The above strategies were apparently able to counteract a clear reduction in both food quality and size of feeding trees. Conclusions/Significance Our findings indicate that collared lemurs in littoral forest fragments modified their behavior to cope with the pressures of fluctuating resource availability. The observed flexibility is likely to be an adaptation to Malagasy rainforests, which are known to undergo periods of fruit scarcity and low productivity. These results should be carefully considered when relocating lemurs or when selecting suitable areas for

  2. Historical changes in the shoreline and littoral processes on a headland bay beach in central Chile

    NASA Astrophysics Data System (ADS)

    Martínez, Carolina; Quezada, Matías; Rubio, Patricio

    2011-12-01

    We applied parabolic and logarithmic adjustments and methods of cartographic overlay to the sandy littoral of Concón bay (Central Chile) to determine the changes associated with the shoreline and their relation with littoral processes, in a typical bay on an active continental margin and with a microtidal regime. A set of historical reference points was built by means of aerial photographs and topographies for the period 1945-2008. Given the form of the shoreline, to the southern section of the bay we applied the classical logarithmic formula of Yasso (1965) and the functions incorporated in the Coastal Modeling System (Sistema de Modelamiento Costero, SMC) of the Universidad de Cantabria. In the northern section a method of map overlay was applied. The Oluca-SP model of the SMC was used to determine the influence of waves (refraction) on the types of changes of the shoreline. Information on waves (1985-2006), mean sea level (2001-2006) and variations in the mean size of beach sediment were used to relate the changes in the plan form of the bay. There has been little spatio-temporal variability in the shoreline of the bay over the last 65 years. The southern section had a mean shoreline retreat rate of - 0.55 m/year (1945-2008) in spite of the large variability produced in an estuary dominated by waves. The best adjustment was obtained with the logarithmic function. In the northern section the mean accretion rate was 0.39 m/year (1954-2008). The plan form and the historical changes of the shoreline are closely associated with the seasonal changes of the waves and the presence of rocky thresholds in the area. The mean sea level did not produce important effects in the types of change.

  3. Microbial Iron(II) Oxidation in Littoral Freshwater Lake Sediment: The Potential for Competition between Phototrophic vs. Nitrate-Reducing Iron(II)-Oxidizers

    PubMed Central

    Melton, E. D.; Schmidt, C.; Kappler, A.

    2012-01-01

    The distribution of neutrophilic microbial iron oxidation is mainly determined by local gradients of oxygen, light, nitrate and ferrous iron. In the anoxic top part of littoral freshwater lake sediment, nitrate-reducing and phototrophic Fe(II)-oxidizers compete for the same e− donor; reduced iron. It is not yet understood how these microbes co-exist in the sediment and what role they play in the Fe cycle. We show that both metabolic types of anaerobic Fe(II)-oxidizing microorganisms are present in the same sediment layer directly beneath the oxic-anoxic sediment interface. The photoferrotrophic most probable number counted 3.4·105 cells·g−1 and the autotrophic and mixotrophic nitrate-reducing Fe(II)-oxidizers totaled 1.8·104 and 4.5·104 cells·g−1 dry weight sediment, respectively. To distinguish between the two microbial Fe(II) oxidation processes and assess their individual contribution to the sedimentary Fe cycle, littoral lake sediment was incubated in microcosm experiments. Nitrate-reducing Fe(II)-oxidizing bacteria exhibited a higher maximum Fe(II) oxidation rate per cell, in both pure cultures and microcosms, than photoferrotrophs. In microcosms, photoferrotrophs instantly started oxidizing Fe(II), whilst nitrate-reducing Fe(II)-oxidizers showed a significant lag-phase during which they probably use organics as e− donor before initiating Fe(II) oxidation. This suggests that they will be outcompeted by phototrophic Fe(II)-oxidizers during optimal light conditions; as phototrophs deplete Fe(II) before nitrate-reducing Fe(II)-oxidizers start Fe(II) oxidation. Thus, the co-existence of the two anaerobic Fe(II)-oxidizers may be possible due to a niche space separation in time by the day-night cycle, where nitrate-reducing Fe(II)-oxidizers oxidize Fe(II) during darkness and phototrophs play a dominant role in Fe(II) oxidation during daylight. Furthermore, metabolic flexibility of Fe(II)-oxidizing microbes may play a paramount role in the

  4. Invasive Mussels Alter the Littoral Food Web of a Large Lake: Stable Isotopes Reveal Drastic Shifts in Sources and Flow of Energy

    PubMed Central

    Ozersky, Ted; Evans, David O.; Barton, David R.

    2012-01-01

    We investigated how establishment of invasive dreissenid mussels impacted the structure and energy sources of the littoral benthic food web of a large temperate lake. We combined information about pre- and postdreissenid abundance, biomass, and secondary production of the littoral benthos with results of carbon and nitrogen stable isotope analysis of archival (predreissenid) and recent (postdreissenid) samples of all common benthic taxa. This approach enabled us to determine the importance of benthic and sestonic carbon to the littoral food web before, and more than a decade after dreissenid establishment. Long term dreissenid presence was associated with a 32-fold increase in abundance, 6-fold increase in biomass, and 14-fold increase in secondary production of the littoral benthos. Dreissenids comprised a large portion of the post-invasion benthos, making up 13, 38, and 56% of total abundance, biomass, and secondary production, respectively. The predreissenid food web was supported primarily by benthic primary production, while sestonic material was relatively more important to the postdreissenid food web. The absolute importance of both sestonic material and benthic primary production to the littoral benthos increased considerably following dreissenid establishment. Our results show drastic alterations to food web structure and suggest that dreissenid mussels redirect energy and material from the water column to the littoral benthos both through biodeposition of sestonic material as well as stimulation of benthic primary production. PMID:23284673

  5. Pb isotopic study on soils from Domizio-Flegreo Littoral area, Napoli, Italy

    NASA Astrophysics Data System (ADS)

    Grezzi, G.; Ayuso, R. A.; Lima, A.; Albanese, S.; de Vivo, B.

    2009-04-01

    The Domizio - Flegreo Littoral area, together with the Agro Aversano area, are part of a Site of National Interest for pollution assessment. This area is located along the north coastal zone of the Campania region (Italy) and has an extension of about 855 Km2. We analyzed soils for heavy metal content in order to study and discriminate the impact of natural and anthropogenic sources. We collected 292 soil surface samples (5-15 cm depth) and produced maps showing the distribution of heavy metals in the soils. On the basis of the geographic distribution of heavy metals, 9 soil profiles were also collected for detailed examination (1 meter from surface). From each soil profile, we collected 10 soil samples (1/10 cm) in the urban and suburban areas of the littoral area. Also, we collected 8 groundwater samples likely associated with the soils. Pb isotope compositions of these soils and waters help to constrain the impact of anthropogenic and natural components on the soil profiles. Possible anthropogenic end-members include pesticides used in the area. Lead isotope compositions of soils known to contain anomalously high values of heavy metals were measured in order to determine the sources of the Pb and, by inference, sources of other metals that are likely to share similar geochemical behaviour in the surface environment (e.g., As). Acid-leach compositions of the soils represent Pb that is adsorbed to mineral surfaces, whereas residue compositions may reflect bedrock. Labile Pb (acid-leach fractions) from the soils shows a range in compositions of 207Pb/206Pb = 0.8275 to 0.8486, and 208Pb/206Pb = 2.0488 to 2.0873. The isotope values vary and decrease with depth. The Pb isotope ratios obtained on groundwater samples range from about 207Pb/206Pb = 0.8516 to 0.8636, 208Pb/206Pb = 2.0706 to 2.1064. The Pb isotope ratios in the soil profiles and groundwater are generally consistent with multiple sources that include anthropogenic Pb. Surface soil samples from Giugliano

  6. The utilization of ERTS-1 data for the study of the French Atlantic Littoral. [coastal water and geomorphology

    NASA Technical Reports Server (NTRS)

    Demathieu, P. G.; Verger, F. H.

    1974-01-01

    The French Atlantic Littoral (FRALIT) program uses ERTS-1 data to study coastal geomorphology and waters. ERTS-1 gives an overall picture of the phenomena for the first time due mainly to channel 4 data, but the other channels also contribute valuable complementary data on superficial waters. These studies have already resulted in accurate maps of the mud transported south-westwards from the mouth of the River Loire.

  7. An integrated evaluation of the persistence and effects of 4-nonylphenol in an experimental littoral ecosystem

    SciTech Connect

    Liber, K.; Knuth, M.L.; Stay, F.S.

    1999-03-01

    A comprehensive littoral enclosure study was conducted to assess the persistence and distribution of 4-nonylphenol (NP) in a littoral ecosystem, and to evaluate the compound`s effects on resident aquatic biota. Enclosures with a mean ({+-} SD) surface area and volume of 31.4 {+-} 3.3 m{sup 2} and 32.0 {+-} 6.4 m{sup 3}, respectively, received eleven applications at 48-h intervals with one of four different rates of NP. This created a 20-d application period which was followed by a three to fourteen month observation period, depending on the endpoint measured. Mean {+-} SD NP concentrations in the water column measured 2 h after each application averaged 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L at nominal treatments of 3, 30, 100, and 300 {micro}g/L, respectively. Persistence in the water column was relatively short, with a dissipation half-life estimated at {le} 1.2 d. Persistence of NP in sediment and on macrophytes was substantially longer, with estimated half-lives of 28 to 104 d and 8 to 13 d, respectively. Zooplankton was the most sensitive group of organisms evaluated, with significant reductions in population abundances of some copepod taxa observed at the 23 {+-} 11-{micro}g/L treatment. Fish survival was affected at 243 {+-} 41 {micro}g/L. The most sensitive benthic macroinvertebrate taxon, Pisidium (Bivalvia) was affected at 76 {+-} 21 {micro}g/L, but most taxa were only affected at the 243 {+-} 41-{micro}g/L treatment. None of the assessed populations were affected at the 5 {+-} 4-{micro}g/L treatment. Macrophytes and periphyton were not adversely affected by any of the treatments. Overall community composition, assessed at the family level or higher, was not affected at or below the 23 {+-} 11-{micro}g/L treatment, but did exhibit substantial changes at the 243 {+-} 41-{micro}g/L treatment. Some minor changes were observed at the 76 {+-} 21-{micro}g/L treatment. The maximum acceptable toxicant concentration in the water column, based

  8. Shoreline variations and coastal dynamics: A space-time data analysis of the Jonian littoral, Italy

    NASA Astrophysics Data System (ADS)

    Aiello, Antonello; Canora, Filomena; Pasquariello, Guido; Spilotro, Giuseppe

    2013-09-01

    Morphological variations of coastlines are caused by several key processes that are influenced by climate conditions, sea level variations, wave energy, tectonics and human-induced phenomena. These processes affect the dynamics of catchment basins and the coastal environment. Since the second half of the 20th century, the Jonian coast of the Basilicata Region (Italy) has witnessed a widespread retreating phenomenon, predominantly due to anthropogenic causes affecting transport processes along the riverbeds and causing reductions in the sediment supply to the coast. The disturbance in the balance between sediment transport carried out by the sea and the sediment supply performed by rivers has led to a deficit in the sediment budget. To understand the morphological dynamics of the littoral environment and quantify the amount of coastal erosion, an analysis of coastline change has been carried out using various data sources: historical cartography, aerial photographs and GPS surveys. Between 1870 and 1954, the 32-km-long Jonian littoral under examination showed an accretion trend, while the loss in beach surface steadily increased between 1954 and 2005. The average change in beach surface has been calculated as about +55,000 m2/yr (accretion) between 1870 and 1954 and -16,500 m2/yr (erosion) between 1954 and 2005. Overall, 640,000 m2 of sandy beaches were lost along the entire Jonian coast of the Basilicata Region between 1954 and 2005. Comparing the shoreline between 1870 and 1954, the average net shoreline movement (NSM) is +110 m vs. -30 m between 1954 and 2005. This analysis approach has proven to be effective in quantifying the erosion phenomenon and its effects, despite the lack of homogeneous data series and the variety of spatial and temporal scales over which coastal evolution occurs. The study represents an important step in understanding coastal dynamics in this region. As coastal areas are being affected by an increasing number of population and socio

  9. Habitat selection by three littoral zone fishes: effects of predation pressure, plant density and macrophyte type

    USGS Publications Warehouse

    Chick, J.H.; McIvor, C.C.

    1997-01-01

    We conducted laboratory experiments which demonstrated that three littoral zone fishes differentially selected among three macrophytes when seeking refuge from predation. In the presence of a predator (a juvenile Micropterus salmoides), mosquitofish (Gambusia holbrooki), sailfin mollies (Poecilia latipinna). and dollar sunfish (Lepomis marginatus) displayed ferential use of four tank areas containing patches of either Hydrilla verticillata, Potamogeton illinoensis, Panicum hemitomon, or no plants. Patterns habitat selection, and the consistency of these patterns among replicates, differed among the three fishes and among three plant-density treatments - natural (each macrophyte presented at its mean field density), equal (all three macrophytes at the same density), and control (no plants). Selection for H. verticillata by mosquitofish was significant for both the equal and natural treatments, and thus was not caused by differences in plant density alone. Sailfin mollies displayed significant selection for H. verticillata only in the natural plant-density treatments. Dollar sunfish showed less consistent habitat selection than either mosquitofish or sailfin mollies. Significant habitat selection was not found in the absence of a predator, and there was no evidence for lection among the tank areas in control treatments. Patterns of habitat selection by the three fishes in our laboratory study corresponded to observed habitat use in Lake Okeechobee.

  10. [Taxonomic composition and distribution of the echinoderms associations in the littoral ecosystems from the Colombian Pacific].

    PubMed

    Neira, Raúl; Cantera, Jaime R

    2005-12-01

    This paper examines published information and gray literature about taxonomy and ecology of echinoderm species of the Colombian Pacific Coast. Unpublished collection data of specimens kept in the Marine Sciences Museum of the University of Valle are also considered. Sixty-six species are found in coastal ecosystems and shallow bottoms of ten geographical, coastal and insular localities of the Pacific coast of Colombia. Main habitats having echinoderms are: rocky cliffs and shores, coral reefs, sand beaches, mud substrates, mangroves, and shallow bottoms of mud, sand, gravel and rocks. Regular Echinoidea and Asteroidea are the most diverse and abundant groups, mainly in subtidal rocky shallow bottoms and coral reefs. Ophiuroidea are abundant below rocky boulders. Irregular Echinoidea are abundant on sand beaches. The relatively high number of species shows that this geographical area presents a high diversity of echinoderms compared with other tropical shallow and littoral zones of the world. Rocky substrates and coral reefs are the ecosystems with the highest numbers of echinoderm species and individuals. A conservation status assessment is difficult because the lack of periodical sampling and few data about deep zones. In general, the species reported in the last 25 years, have not experimented important changes in their populations, although in some specific places, populations may decrease because human activities in coastal areas increase sedimentation rates change some rocky substrates to mud or sand. PMID:17471612

  11. Comparative diversity analysis in sandy littoral ecosystems of the western Mediterranean

    NASA Astrophysics Data System (ADS)

    Colombini, I.; Fallaci, M.; Milanesi, F.; Scapini, F.; Chelazzi, L.

    2003-10-01

    A comparative faunal analysis was carried out in sandy littoral localities differing both morphologically and in human impact. The study sites were located in the western Mediterranean basin along the coasts of Morocco, Tunisia, the Maltese Islands and Italy. These were typical beach-dune ecosystems more (Smir, Morocco; Zouara, Tunisia; Burano, Italy) or less (Ir-Ramla tat-Torri, Malta and Ir-Ramla l-Hamra, Gozo) structurally developed accordingly. Species richness was evaluated using standard trapping techniques with pitfall traps along the transects perpendicular to the shoreline. Only isopods and coleopterans were used in the analysis. In each locality, an analysis was conducted on both the beach and the dune separately, and on the entire ecosystem in the two seasons (spring and autumn). Species were studied both quantitatively and qualitatively using ecological coefficients (relative abundance) and Fisher's diversity index. To evaluate the evenness of the community, Shannon-Weaver index was calculated and compared with Brillouin index. For both indices, the maximum values were computed and were used to obtain the evenness of the community through Pielou index. In addition, Simpson's dominance index was considered. Percentages of similarities between localities were analysed in the two seasons and in total using the Renkonen index. The overall analysis showed that general trends could be found for both orders that were studied and gave indications on habitat quality. The study showed that when monitoring was carried out systematically both in space and time, arthropods could be used as important tool to assess beach health.

  12. Applying a reservoir functional-zone paradigm to littoral bluegills: differences in length and catch frequency?

    PubMed Central

    DeAngelis, Holly; Crosby, Abigale M.; Roosenburg, Willem M.

    2014-01-01

    Reservoirs exhibit gradients in conditions and resources along the transition from lotic to lentic habitat that may be important to bluegill ecology. The lotic–lentic gradient can be partitioned into three functional zones: the riverine, transitional, and lacustrine zones. We measured catch frequency and length of bluegills (Lepomis macrochirus) captured along the periphery of these areas (i.e., in the littoral zone of each functional zone) for four small reservoirs in Southeastern Ohio during the summer months of three years. Catch frequency differed between zones for two reservoirs, but these differences were not observed in other years. There was no relationship between reservoir zone and either standard length or catch frequency when the data for all reservoirs were pooled, but we did observe a bimodal length distribution in all reservoirs. A combination of ecological factors including inter and intraspecific competition, predation intensity, management practices, limnology, and assemblage complexity may be mitigating bluegill distribution and abundance in reservoirs. Therefore, a functional zone (categorical) approach to understanding bluegill ecology in reservoirs may not be appropriate. PMID:25177535

  13. Restoring ecosystem services to littoral zones of rivers in the urban core of Chongqing, China.

    PubMed

    Xian, Xu-Dong; Feng, Yi-Long; Willison, J H Martin; Ai, Li-Jiao; Wang, Ping; Wu, Zhi-Neng

    2015-08-01

    Two examples of the creation of naturalized areas in the littoral zone of the Three Gorges Reservoir in the urban core of Chongqing City, China, are described. The areas were created for the purpose of restoring ecological functions and services. Plants were selected based on surveys of natural wetland vegetation in the region, and experiments were conducted to discover the capacity of species of interest to survive the sometimes extreme hydrological regimes at the sites. Novel methods were developed to stabilize the plants against the rigors of extreme summer floods and constant swash, notably zigzag berms of rocks wrapped in iron mesh. The areas include native reeds, grasses, shrubs, and trees. Plant communities in the areas are zoned according to flooding stress, and their structure is less stable at lower elevations that are subjected to greater stress. The tall grass Saccharum spontaneum (widespread in Southern Asia) and the tree Pterocarya stenoptera (native to Southwest China) are notable for their utility at these sites in the center of a large city. Communities of tall reeds and grasses have become so dense and stable that they now provide the ecosystem services of capturing river sediments and resisting erosion of the river banks. It is recommended that extensive greening of the riparian zones in urban areas of the Three Gorges Reservoir be conducted for the purpose of providing ecosystem services, based in part on the experiences described here. PMID:25907628

  14. Effects of 4-nonylphenol on the biota in a littoral pond ecosystem

    SciTech Connect

    Liber, K.; Schmude, K.; O`Halloran, S.; Corry, T.; Gangl, J.; Stay, F.

    1994-12-31

    National water quality criteria for 4-nonylphenol, a surfactant precursor and metabolite, are currently being developed by the US EPA. Preliminary data from laboratory tests indicate that the criterion maximum concentration may be as low as 3--10 {mu}g/L; field data on biological effects are rare. The study presented here was designed to assess the effects of 4-nonylphenol on a natural aquatic community using a set of 18 littoral enclosures (average volume 33 m{sup 3}). The common occurrence of 4-nonylphenol in municipal and industrial discharges dictated the use of a ``chronic`` exposure scenario for this study. Test concentrations ranged from 3 to 300 {mu}g/L, with applications every 48 hours for a 20 day period. This ensured a 21-day ``chronic`` exposure period and allowed sediment concentration of 4-nonylphenol to steadily increase. Survival of juvenile bluegill sunfish was reduced at 300 {mu}g/L, but not at 100, {mu}g/L; no effects on growth were noted over the 68-day assessment period. Abundance of Cladocera and Copepoda were also reduced at 300 {mu}g/L, with recovery observed within 2--4 weeks after the last nonylphenol application. Benthic macroinvertebrates, including Chironomidae, Oligochaeta, and Mollusca, were affected at 100--300 {mu}g/L, with impacts persisting for several months. The slow recovery of benthic macroinvertebrates was partially attributed to their prolonged exposure to sediment associated nonylphenol residues.

  15. Comparison of species composition and richness of fish assemblages in altered and unaltered littoral habitats

    USGS Publications Warehouse

    Poe, T.P.; Hatcher, C.O.; Brown, C.L.; Schloesser, D.W.

    1986-01-01

    Species composition and richness of fish assemblages in altered and unaltered littoral habitats in Lake St. Clair, Michigan, differed between areas. A percid-cyprinid-cyprinodontid assemblage dominated in the unaltered area, Muscamoot Bay, which has a natural shoreline (with almost no alteration due to dredging or bulkheading), high water quality, and high species richness of aquatic macrophytes. A centrarchid assemblage dominated in the altered area, Belvidere Bay, which has a bulkheaded shoreline, many dredged areas, reduced water quality due to inputs of nutrients from a nearby river, and relatively low species richness of aquatic macrophytes. Habitat factors, species richness and abundance of aquatic macrophytes, had the most influence on fish community structure in both areas. The percid-cyprinid-cyprinodontid assemblage was significantly correlated with six species of macrophytes whereas the centrarchid assemblage was significantly correlated with only four. These patterns suggest that preference for diverse habitats was higher, and tolerance to habitat alteration lower, in percid-cyprinid-cyprinodontid assemblages than in centrarchid assemblages.

  16. Spectral identification of sperm whales from Littoral Acoustic Demonstration Center passive acoustic recordings

    NASA Astrophysics Data System (ADS)

    Sidorovskaia, Natalia A.; Richard, Blake; Ioup, George E.; Ioup, Juliette W.

    2005-09-01

    The Littoral Acoustic Demonstration Center (LADC) made a series of passive broadband acoustic recordings in the Gulf of Mexico and Ligurian Sea to study noise and marine mammal phonations. The collected data contain a large amount of various types of sperm whale phonations, such as isolated clicks and communication codas. It was previously reported that the spectrograms of the extracted clicks and codas contain well-defined null patterns that seem to be unique for individuals. The null pattern is formed due to individual features of the sound production organs of an animal. These observations motivated the present studies of adapting human speech identification techniques for deep-diving marine mammal phonations. A three-state trained hidden Markov model (HMM) was used with the phonation spectra of sperm whales. The HHM-algorithm gave 75% accuracy in identifying individuals when it had been initially tested for the acoustic data set correlated with visual observations of sperm whales. A comparison of the identification accuracy based on null-pattern similarity analysis and the HMM-algorithm is presented. The results can establish the foundation for developing an acoustic identification database for sperm whales and possibly other deep-diving marine mammals that would be difficult to observe visually. [Research supported by ONR.

  17. Treatment of angiomas and telangiectasias

    NASA Astrophysics Data System (ADS)

    Kubota, Junichiro

    2003-12-01

    Background Vascular lesions still present a major problem, and the search for a good treatment continues. The use of inappropriate treatment methods, can occasionally cause unwanted side effects. Even when the method used is appropriate, the result can be disappointing. It is important to choose an appropriate laser, and where laser treatment is not effective, we must select the most appropriate conventional treatment or combination of treatments. My treatment program is as follows; a 532 nm diode laser is the first choice for telangiectasias; the flashlamp-pumped dye laser for port wine stains and strawberry marks; and the Nd:YAG laser with a cooling device for 1 - 3 mm leg veins of the reticular and web type. For leg veins over 3 mm, surgery is required. The diode pumped 532 nm laser is excellent for superficial telangiectasias. Good effects with the pulsed dye laser are limited to vessels in the upper layers of the dermis, thus the penetration depth of the laser must thus be optimized combined with epidermal cooling. We must always avoid side effects in laser treatment of vascular lesions. Development of new wavelengths and adaptation of existing wavelengths are currently being investigated.

  18. Southwest Washington Littoral Drift Restoration Project: Beach and Nearshore Morphological Monitoring

    NASA Astrophysics Data System (ADS)

    Gelfenbaum, G. R.; Stevens, A. W.; Ruggiero, P.; Kaminsky, G. M.

    2010-12-01

    Shoreline change along the southwest Washington and northwest Oregon coast responds to both natural and anthropogenic drivers at a range of temporal and spatial scales. Within the last century, human interventions, primarily the construction of large jetties at the entrance to the Columbia River, have been the dominant driver of nearshore morphology and shoreline change in this area. These jetties caused the inlet to narrow and deepen, the ebb-tidal delta to migrate offshore into deeper water, and adjacent shorelines to first accrete then erode over distances of tens of kilometers and time scales of decades. Shoreline change modeling suggests that reduced local sediment supply owing to these morphological changes is causing a deficit of sand feeding the shoreline, especially in the region of Benson Beach, just north of the mouth of the Columbia River. One of the goals of the Southwest Washington Littoral Drift Restoration (SW LDR) project is to assess the long-term viability of placing dredged material from the mouth of the Columbia River (MCR) directly on Benson Beach to supplement the littoral sediment budget. The SW LDR will be one of the largest beach nourishment projects in the Pacific Northwest, with approximately 200,000 - 400,000 m3 of dredged material being placed on Benson Beach during the summer of 2010. Extensive monitoring and modeling efforts are underway to evaluate the effectiveness of the project and to develop morphodynamic modeling tools to inform future Regional Sediment Management decisions. Overall project components include Argus beach monitoring, measurements of nearshore waves and currents, deployment of a sand tracer, morphodynamic modeling, and a morphological monitoring program. The primary purpose of the morphological monitoring program, and the focus for this presentation, is to track the response of beach and nearshore areas during and after the sand placement. Bathymetric data, collected using Personal Watercraft (PWCs) equipped with

  19. Strategies of zooplanktivory shape the dynamics and diversity of littoral plankton communities: a mesocosm approach.

    PubMed

    Helenius, Laura K; Aymà Padrós, Anna; Leskinen, Elina; Lehtonen, Hannu; Nurminen, Leena

    2015-05-01

    Planktivorous fish can exert strong top-down control on zooplankton communities. By incorporating different feeding strategies, from selective particulate feeding to cruising filter feeding, fish species target distinct prey. In this study, we investigated the effects of two species with different feeding strategies, the three-spined stickleback (Gasterosteus aculeatus (L.)) and roach (Rutilus rutilus (L.)), on a low-diversity brackish water zooplankton community using a 16-day mesocosm experiment. The experiment was conducted on a small-bodied spring zooplankton community in high-nutrient conditions, as well as a large-bodied summer community in low-nutrient conditions. Effects were highly dependent on the initial zooplankton community structure and hence seasonal variation. In a small-bodied community with high predation pressure and no dispersal or migration, the selective particulate-feeding stickleback depleted the zooplankton community and decreased its diversity more radically than the cruising filter-feeding roach. Cladocerans rather than copepods were efficiently removed by predation, and their removal caused altered patterns in rotifer abundance. In a large-bodied summer community with initial high taxonomic and functional diversity, predation pressure was lower and resource availability was high for omnivorous crustaceans preying on other zooplankton. In this community, predation maintained diversity, regardless of predator species. During both experimental periods, predation influenced the competitive relationship between the dominant calanoid copepods, and altered species composition and size structure of the zooplankton community. Changes also occurred to an extent at the level of nontarget prey, such as microzooplankton and rotifers, emphasizing the importance of subtle predation effects. We discuss our results in the context of the adaptive foraging mechanism and relate them to the natural littoral community. PMID:26045953

  20. Integrative assessment of sediment quality in two littoral ecosystems from the Gulf of Cadiz, Spain

    SciTech Connect

    DelValls, T.A.; Forja, J.M.; Gomez-Parra, A. |

    1998-06-01

    To evaluate sediment marine environmental quality in the Gulf of Cadiz, an integrative assessment approach was used--the sediment quality triad (SQT). Sediment samples were collected at seven stations in two littoral ecosystems and subjected to six separate, replicated sediment toxicity tests, comprehensive sediment chemistry analyses, and replicated benthic infaunal analyses. Chemistry analyses indicated that different contamination sources were associated with sediments highly contaminated with linear alkylbenzenesulfonates and some heavy metals associated with sewage discharges (Pb, and Ag), sediments with moderate levels of heavy metals associated with industrial activities (Hg, Cr, and As), and other sediments with slight or no contamination. Toxicity tests indicated that sediments close to the sewage discharges were most toxic, those associated with slight or no contamination were not toxic, and those associated with both sewage discharges and industrial sources of contamination were intermediate. Infaunal analyses indicated that communities at the salt-marsh of the Barbate River stations and CB2 station in the Bay of Cadiz were the most altered, whereas those at CB5 and CB3 in the Bay of Cadiz were slightly altered, relative to stations CB1 and CB4 in the Bay of Cadiz. A different methodology to calculate the ratio-to-reference and each composite SQT index value is proposed by adding to the classical normalization by using the reference clean station as a new normalization that includes a reference polluted station to establish a between-the-maximum and minimum level obtained in the area studied. The authors propose this new methodology to calculate weighted results based on the fact that they are obtained using two points of reference for comparison. The results show that sediment pollution is restricted to the vicinity of one untreated sewage discharge in the Bay of Cadiz.

  1. Strategies of zooplanktivory shape the dynamics and diversity of littoral plankton communities: a mesocosm approach

    PubMed Central

    Helenius, Laura K; Aymà Padrós, Anna; Leskinen, Elina; Lehtonen, Hannu; Nurminen, Leena

    2015-01-01

    Planktivorous fish can exert strong top-down control on zooplankton communities. By incorporating different feeding strategies, from selective particulate feeding to cruising filter feeding, fish species target distinct prey. In this study, we investigated the effects of two species with different feeding strategies, the three-spined stickleback (Gasterosteus aculeatus (L.)) and roach (Rutilus rutilus (L.)), on a low-diversity brackish water zooplankton community using a 16-day mesocosm experiment. The experiment was conducted on a small-bodied spring zooplankton community in high-nutrient conditions, as well as a large-bodied summer community in low-nutrient conditions. Effects were highly dependent on the initial zooplankton community structure and hence seasonal variation. In a small-bodied community with high predation pressure and no dispersal or migration, the selective particulate-feeding stickleback depleted the zooplankton community and decreased its diversity more radically than the cruising filter-feeding roach. Cladocerans rather than copepods were efficiently removed by predation, and their removal caused altered patterns in rotifer abundance. In a large-bodied summer community with initial high taxonomic and functional diversity, predation pressure was lower and resource availability was high for omnivorous crustaceans preying on other zooplankton. In this community, predation maintained diversity, regardless of predator species. During both experimental periods, predation influenced the competitive relationship between the dominant calanoid copepods, and altered species composition and size structure of the zooplankton community. Changes also occurred to an extent at the level of nontarget prey, such as microzooplankton and rotifers, emphasizing the importance of subtle predation effects. We discuss our results in the context of the adaptive foraging mechanism and relate them to the natural littoral community. PMID:26045953

  2. Discontinuous ammonia excretion and glutamine storage in littoral Oniscidea (Crustacea: Isopoda): testing tidal and circadian models.

    PubMed

    Nakamura, Maya; Wright, Jonathan C

    2013-01-01

    A key evolutionary development facilitating land colonization in terrestrial isopods (Isopoda: Oniscidea) is the intermittent liberation of waste nitrogen as volatile ammonia. Intermittent ammonia release exploits glutamine (Gln) as an intermediary nitrogen store. Here, we explore the relationship between temporal patterns of ammonia release and Gln accumulation in three littoral oniscideans from Southern California. Results are interpreted in terms of water availability, habitat, activity patterns, and ancestry. A two-way experimental design was used to test whether ammonia excretion and Gln accumulation follow a tidal or diel periodicity. Ammonia excretion was studied in the laboratory using chambers with or without available seawater and using an acid trap to collect volatile ammonia. Ligia occidentalis releases ammonia directly into seawater and accumulates Gln during low tide (48.9 ± 6.5 μmol g⁻¹ at low tide, 24.1 ± 3.0 μmol g⁻¹ at high tide), indicating that excretion is tidally constrained. Alloniscus perconvexus and Tylos punctatus can excrete ammonia directly into seawater or utilize volatilization. Both species burrow in sand by day and show a diel excretory pattern, accumulating Gln nocturnally (31.8 ± 2.7 μmol g⁻¹ at dawn and 21.8 ± 2.3 μmol g⁻¹ at dusk for A. perconvexus; 85.7 ± 15.1 μmol g⁻¹ at dawn and 25.4 ± 2.9 μmol g⁻¹ at dusk for T. punctatus) and liberating ammonia diurnally. Glutaminase shows higher activity in terrestrial (0.54-0.86 U g⁻¹) compared to intertidal (0.25-0.31 U g⁻¹) species, consistent with the need to generate high PNH₃ for volatilization. The predominant isoform in Armadillidium vulgare is phosphate dependent and maleate independent; phosphate is a plausible regulator in vivo. PMID:22836297

  3. Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar)

    PubMed Central

    2013-01-01

    Background The country of Madagascar is renowned for its high level of biodiversity and endemism, as well as the overwhelming pressures and threats placed on the natural resources by a growing population and climate change. Traditional medicine plays an important role in the daily lives of the Malagasy for various reasons including limited access to healthcare, limited markets and traditional values. The objective of this study was to assess the modern utitilization of the Agnalazaha Forest by the local population in Mahabo-Mananivo, Madagascar, for medicinal plants used by women, and to establish a list of medicinal plants used by women sourced from Agnalazaha Forest. Methods Ethnobotanical studies were conducted over a period of five months in 2010 to determine the diversity of medicinal plants used by women in the commune of Mahabo-Mananivo. In all, 498 people were interviewed, both male and female ranging age from 15 to over 60 years old. Results 152 medicinal plants used by local people were collected during the ethnobotanical studies. Among the recorded species, eight native species are widely used by women. These species are known for their therapeutic properties in treating placental apposition and complications during childbirth as well as tropical illnesses such as malaria, filariasis, and sexual diseases like gonorrhea and syphilis. Conclusions Littoral forests are rare ecosystems that are highly threatened on the island nation of Madagascar. Our investigation into the use of medicinal plants sourced from and around the Agnalazaha Forest by the women of Mahabo-Mananivo reinforces the need for this natural resource as a first line of health care for rural families. PMID:24188563

  4. Survey of pesticide application on vegetables in the Littoral area of Togo.

    PubMed

    Adjrah, Yao; Dovlo, Agbéko; Karou, Simplice D; Eklu-Gadegbeku, Kwashie; Agbonon, Amégnona; de Souza, Comlan; Gbeassor, Messanvi

    2013-01-01

    Vegetable production in Togo is seriously affected by pests attack. To reduce damage, farmers indiscriminately use pesticides. Various studies have reported high concentrations of pesticide residues more than acceptable limits in vegetables and other edible food. The aim of the presented study is to study the attitudes and practices developed by vegetable growers about pesticides applications. A standardized questionnaires which included socio-professional factors, provisions and operations concerning the use of varieties of pesticides were addressed to 150 growers in vegetable farms along the Littoral of Togo. In order to complete data concerning pesticides, seven runoff private companies and agents of the 'Direction de la Protection des Végétaux' were interviewed. Data were statistical treated using Sphinx Plus. The survey showed that vegetable growers have an acceptable educational level (36% have more than 7 years of formal education) to exploit instructions concerning pesticide use, but more than 97% do not use recommended tools. Only 21% of them received training for pesticide use. Moreover, 84% of them did not usually wear gloves, and less than 30% used oro-nasal masks. Failure to observe minimum intervals between pesticide application and sale is worrying because extremely hazardous (Carbofuran and Cadusaphos) or moderately toxic (Cypermethrin, Dimethoate, Endosulfan, Chlorpyrifos-ethyl, Fipronil) are the products currently used. The presented study indicates that pesticides application in the survey area represents a potential risk for the environment, farmers and consumers. More investigations are needed to quantify pesticides residues on the vegetables currently con,umed and moreover, to determine the potential effect of those products on human and animals health. PMID:24364441

  5. Exposure of juvenile green frogs (Lithobates clamitans) in littoral enclosures to a glyphosate-based herbicide.

    PubMed

    Edge, Christopher B; Gahl, Megan K; Pauli, Bruce D; Thompson, Dean G; Houlahan, Jeff E

    2011-07-01

    The majority of studies on the toxicity of glyphosate-based herbicides to amphibians have focused on larval life stages exposed in aqueous media. However, adult and juvenile amphibians may also be exposed directly or indirectly to herbicides. The potential for such exposures is of particular interest in the littoral zone surrounding wetlands as this is preferred habitat for many amphibian species. Moreover, it may be argued that potential herbicide effects on juvenile or adult amphibians could have comparatively greater influence on overall recruitment, reproductive potential and thus stability of local populations than effects on larvae. In this experiment, juvenile green frogs (Lithobates clamitans) were exposed to two concentrations (2.16 and 4.27 kg a.e./ha) of a glyphosate-based herbicide formulation (VisionMax®), which were based on typical application scenarios in Canadian forestry. The experimental design employed frogs inhabiting in situ enclosures established at the edge of small naturalized wetlands that were split in half using an impermeable plastic barrier. When analyzed using nominal target application rates, exposure to the glyphosate-based herbicide had no significant effect on survival, body condition, liver somatic index or the observed rate of Batrachochytrium dendrobatidis infection. However, there were marginal trends in both ANOVA analysis and post-hoc regressions regarding B. dendrobatidis infection rates and liver somatic index in relation to measured exposure estimates. Results from this study highlight the importance of field research and the need to include multiple endpoints when examining potential effects of a contaminant on non-target organisms. PMID:21536331

  6. Effects of littoral habitat complexity and sunfish composition on fish production

    USGS Publications Warehouse

    Carey, M.P.; Maloney, K.O.; Chipps, S.R.; Wahl, David H.

    2010-01-01

    Habitat complexity is a key driver of food web dynamics because physical structure dictates resource availability to a community. Changes in fish diversity can also alter trophic interactions and energy pathways in food webs. Few studies have examined the direct, indirect, and interactive effects of biodiversity and habitat complexity on fish production. We explored the effects of habitat complexity (simulated vegetation), sunfish diversity (intra- vs. inter-specific sunfish), and their interaction using a mesocosm experiment. Total fish production was examined across two levels of habitat complexity (low: 161 strands m-2 and high: 714 strands m-2) and two sunfish diversity treatments: bluegill only (Lepomis macrochirus) and bluegill, redear sunfish (Lepomis microlophus), and green sunfish (Lepomis cyanellus) combination. We also measured changes in total phosphorus, phytoplankton, periphyton, and invertebrates to explain patterns in fish production. Bluegill and total fish production were unaffected by the sunfish treatments. Habitat complexity had a large influence on food web structure by shifting primary productivity from pelagic to a more littoral pathway in the high habitat treatments. Periphyton was higher with dense vegetation, leading to reductions in total phosphorus, phytoplankton, cladoceran abundance and fish biomass. In tanks with low vegetation, bluegill exhibited increased growth. Habitat complexity can alter energy flow through food webs ultimately influencing higher trophic levels. The lack of an effect of sunfish diversity on fish production does not imply that conserving biodiversity is unimportant; rather, we suggest that understanding the context in which biodiversity is important to food web dynamics is critical to conservation planning. ?? 2010 John Wiley & Sons A/S.

  7. Effects of 4-nonylphenol on benthic macroinvertebrates and insect emergence in littoral enclosures

    SciTech Connect

    Schmude, K.L.; Liber, K.; Corry, T.D.; Stay, F.S.

    1999-03-01

    The effect of 4-nonylphenol (NP) on benthic, freshwater macroinvertebrates in littoral enclosures was evaluated over a 2-year period. Enclosures received 11 NP applications, 48 h apart, with nominal rates of 3, 30, 100, and 300 {micro}g/L. Mean measured peak concentrations in integrated water column samples over the 20-d application period were 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L NP. Concentrations of NP in the water column decreased rapidly after the last application. Maximum NP concentrations measured in sediments, pore water, and macrophytes of a 300-{micro}g/L enclosure were 27.4 mg/kg, 29.9 {micro}g/L, and 89.6 mg/kg, respectively. The most abundant macroinvertebrate groups, Chironomidae, Oligochaeta, and Mollusca, decreased in abundance after application. Effects on Mollusca were the most severe. Their numbers were significantly reduced at the highest treatment throughout most of the study. Oligochaetes and chironomids were also significantly reduced at the highest treatment, but populations recovered within 6 weeks. Snails and naidid oligochaetes were slightly affected at the second highest treatment (76 {+-} 21 {micro}g/L NP). Insect emergence was reduced during and immediately post-application, but the effects were likely caused or compounded by a surfactant sheen on the surface of the water that interfered with emergence and/or oviposition. The observed effects on the benthic community were most likely due to exposure from the water, although more persistent macrophyte-associated residues may have contributed to effects on Gastropoda, Naididae, and Tanytarsini. Macrophyte-associated NP residues may pose a small risk to benthic organisms, but it is probably minor compared to water exposures. The no-observed and lowest-observed-effect concentration for the benthic community was 23 {+-} 11 and 76 {+-} 21 {micro}g/L NP, respectively.

  8. Strong influence of the littoral zone on sedimentary lipid biomarkers in a meromictic lake.

    PubMed

    Bovee, R J; Pearson, A

    2014-11-01

    Planktonic sulfur bacteria growing in zones of photic zone euxinia (PZE) are important primary producers in stratified, sulfur-rich environments. The potential for export and burial of microbial biomass from anoxic photic zones remains relatively understudied, despite being of fundamental importance to interpreting the geologic record of bulk total organic carbon (TOC) and individual lipid biomarkers. Here we report the relative concentrations and carbon isotope ratios of lipid biomarkers from the water column and sediments of meromictic Mahoney Lake. The data show that organic matter in the central basin sediments is indistinguishable from material at the lake shoreline in both its lipid and carbon isotopic compositions. However, this material is not consistent with either the lipid profile or carbon isotope composition of biomass obtained directly from the region of PZE. Due to the strong density stratification and the intensive carbon and sulfur recycling pathways in the water column, there appears to be minimal direct export of the sulfur-oxidizing planktonic community to depth. The results instead suggest that basinal sediments are sourced via the littoral environment, a system that integrates an indigenous shoreline microbial community, the degraded remains of laterally rafted biomass from the PZE community, and detrital remains of terrigenous higher plants. Material from the lake margins appears to travel downslope, traverse the strong density gradient, and become deposited in the deep basin; its final composition may be largely heterotrophic in origin. This suggests an important role for clastic and/or authigenic minerals in aiding the burial of terrigenous and mat-derived organic matter in euxinic systems. Downslope or mineral-aided transport of anoxygenic, photoautotrophic microbial mats may have been a significant sedimentation process in early Earth history. PMID:25201322

  9. Lethality and bioaccumulation of 4-nonylphenol in bluegill sunfish in littoral enclosures

    SciTech Connect

    Liber, K.; Gangl, J.A.; Corry, T.D.; Heinis, L.J.; Stay, F.S.

    1999-03-01

    Toxicity and bioaccumulation in bluegill sunfish (Lepomis macrochirus) of 4-nonylphenol (NP), a common precursor and degradation intermediate of certain nonionic surfactants, were evaluated in a set of 18 aquatic mesocosms (littoral enclosures) in northeastern Minnesota. Nonylphenol was applied to enclosures every 48 h over a 20-d period (11 applications) at rates of 3, 30, 100, and 300 {micro}g/L. Additional enclosures served as untreated controls. Maximum NP levels in the integrated water column 2 h after each application averaged 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L over the 11 applications at the 3-, 30-, 100-, and 300-{micro}g/L treatments, respectively. Sixty-one percent of the NP dissipated from the water column within {approximately} 39 h of each application. Estimated survival of stocked juvenile bluegills was significantly reduced at the 300-{micro}g/L NP treatment. No significant effects were noted at the other NP treatments; however, the 100-{micro}g/L enclosure with the highest mean NP concentration (93 {+-} 39 {micro}g/L) within that treatment had four to nine times more dead bluegills and four to six times fewer bluegills captured at the end of the season than the other two 100-{micro}g/L enclosures (64 {+-} 23 and 71 {+-} 32 {micro}g/L) and the controls, suggesting increased mortality in this enclosure. Nonylphenol tissue concentrations in juvenile bluegills collected from enclosures treated with 3 and 30 {micro}g/L NP ranged from 0.01 to 2.94 {micro}g/g wet weight and showed a significant positive relationship with the average measured NP concentration in the water. The mean wet weight nonequilibrium NP bioaccumulation factor was 87 {+-} 124. There was no relationship between fish lipid content and NP tissue concentration.

  10. Distribution of living larger benthic foraminifera in littoral environments of the United Arab Emirates

    NASA Astrophysics Data System (ADS)

    Fiorini, Flavia; Lokier, Stephen W.

    2015-04-01

    The distribution of larger benthic foraminifera in Recent littoral environment of the United Arab Emirates (Abu Dhabi and Western regions) was investigated with the aim of understanding the response of those foraminifera to an increase in water salinity. For this purpose, 100 sediment samples from nearshore shelf, beach-front, channel, lagoon, and intertidal environment were collected. Sampling was undertaken at a water depth shallower than 15 m in water with a temperature of 22 to 35˚C, a salinity ranging from 40 to 60‰ and a pH of 8. Samples were stained with rose Bengal at the moment of sample collection in order to identify living specimens. The most abundant epiphytic larger benthic foraminifera in the studied area were Peneroplis pertusus and P. planatus with less common Spirolina areatina, S. aciculate and Sorites marginalis. The living specimens of the above mentioned species with normal test growing were particularly abundant in the nearshore shelf and lagoonal samples collected on seaweed. Dead specimens were concentrated in the coarser sediments of the beach-front, probably transported from nearby environments. Shallow coastal ponds are located in the upper intertidal zone and have a maximum salinity of 60‰ and contain abundant detached seagrass. Samples collected from these ponds possess a living foraminifera assemblage dominated by Peneroplis pertusus and P. planatus. High percentages (up to 50% of the stained assemblage) of Peneroplis presented abnormality in test growth, such as the presence of multiple apertures with reduced size, deformation in the general shape of the test, irregular suture lines and abnormal coiling. The high percentage of abnormal tests reflects natural environmental stress mainly caused by high and variable salinity. The unique presence of living epiphytic species, suggests that epiphytic foraminifera may be transported into the pond together with seagrass and continued to live in the pond. This hypothesis is supported by

  11. Seasonal variations in pore water and sediment geochemistry of littoral lake sediments (Asylum Lake, MI, USA)

    PubMed Central

    Koretsky, Carla M; Haas, Johnson R; Miller, Douglas; Ndenga, Noah T

    2006-01-01

    Background Seasonal changes in pore water and sediment redox geochemistry have been observed in many near-surface sediments. Such changes have the potential to strongly influence trace metal distribution and thus create seasonal fluctuations in metal mobility and bioavailability. Results Seasonal trends in pore water and sediment geochemistry are assessed in the upper 50 cm of littoral kettle lake sediments. Pore waters are always redox stratified, with the least compressed redox stratification observed during fall and the most compressed redox stratification observed during summer. A 2-step sequential sediment extraction yields much more Fe in the first step, targeted at amorphous Fe(III) (hydr)oxides (AEF), then in the second step, which targets Fe(II) monosulfides. Fe extracted in the second step is relatively invariant with depth or season. In contrast, AEF decreases with sediment depth, and is seasonally variable, in agreement with changes in redox stratification inferred from pore water profiles. A 5-step Tessier extraction scheme was used to assess metal association with operationally-defined exchangeable, carbonate, iron and manganese oxide (FMO), organic/sulfide and microwave-digestible residual fractions in cores collected during winter and spring. Distribution of metals in these two seasons is similar. Co, As, Cd, and U concentrations approach detection limits. Fe, Cu and Pb are mostly associated with the organics/sulfides fraction. Cr and Zn are mostly associated with FMO. Mn is primarily associated with carbonates, and Co is nearly equally distributed between the FMO and organics/sulfide fractions. Conclusion This study clearly demonstrates that near-surface lake sediment pore water redox stratification and associated solid phase geochemistry vary significantly with season. This has important ramifications for seasonal changes in the bioavailability and mobility of trace elements. Without rate measurements, it is not possible to quantify the

  12. Ecological speciation in postglacial European whitefish: rapid adaptive radiations into the littoral, pelagic, and profundal lake habitats

    PubMed Central

    Præbel, Kim; Knudsen, Rune; Siwertsson, Anna; Karhunen, Markku; Kahilainen, Kimmo K; Ovaskainen, Otso; Østbye, Kjartan; Peruzzi, Stefano; Fevolden, Svein-Erik; Amundsen, Per-Arne

    2013-01-01

    Understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. Postglacial fishes are excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete environments with variation in available niches. Here, we combine data of niche utilization, trophic morphology, and 17 microsatellite loci to investigate the diversification process of three sympatric European whitefish morphs from three northern Fennoscandian lakes. The morphological divergence in the gill raker number among the whitefish morphs was related to the utilization of different trophic niches and was associated with reproductive isolation within and across lakes. The intralacustrine comparison of whitefish morphs showed that these systems represent two levels of adaptive divergence: (1) a consistent littoral–pelagic resource axis; and (2) a more variable littoral–profundal resource axis. The results also indicate that the profundal whitefish morph has diverged repeatedly from the ancestral littoral whitefish morph in sympatry in two different watercourses. In contrast, all the analyses performed revealed clustering of the pelagic whitefish morphs across lakes suggesting parallel postglacial immigration with the littoral whitefish morph into each lake. Finally, the analyses strongly suggested that the trophic adaptive trait, number of gill rakers, was under diversifying selection in the different whitefish morphs. Together, the results support a complex evolutionary scenario where ecological speciation acts, but where both allopatric (colonization history) and sympatric (within watercourse divergence) processes are involved. PMID:24455129

  13. Catastrophic erosion events on a littoral drift shore: development of washover fields and rates of shoreline retreat on the Atlantic side of Jupiter Island, Florida

    SciTech Connect

    Matlack, P.A.

    1985-01-01

    Parts of the eastern shore of Jupiter Island have retreated more than 140m since 1930. Although many of the low profile, dissipative beaches along the Atlantic coast of the Florida peninsula are in a critical state of erosion, the highest rates of shoreline retreat tend to occur less than 2-3 km downdrift from engineering structures used to stabilize tidal inlets. Compared to other eroding shorelines, Jupiter Island is unusual because 2/3 (20 km) of the eastern shore that extends downdrift of the St. Lucie inlet is severely affected. Decadal shoreline retreats in excess of 25m along this section have been punctuated by documented catastrophic episodes in 1960, 1965, and 1984. Because of the lack of hurricane impact for the past two decades, these accelerated erosional events have been associated with the passage of meteorological fronts or interior high pressure systems that bring about strong onshore northeasterly winds. During periods of extreme storm activity (high waves and wind surge), deep overwash penetration occurs. The 1984 Thanksgiving Day storm, for example, caused extensive shoreline erosion when, in the study area, approximately 6.25 million m/sup 3/ of sediment were shifted 100m inland from the foreshore and near-offshore bars. Some of the larger overwash fans were more than 1m in thickness and extended 150m inland. Possible causes of the catastrophic erosion that occurs along this coastal stretch are being investigated in relation to interactions between littoral drift systems, storm surge, sediment cells, bottom configuration, and engineering structures.

  14. Determining littoral sediment transport paths adjacent to an eroding carbonate beach through net sediment grain-size trend analysis: Lanikai Beach, Hawaii.

    NASA Astrophysics Data System (ADS)

    Bochicchio, C. J.; Fletcher, C.; Vitousek, S.; Romine, B.; Smith, T.

    2007-12-01

    Identifying long-term trends of sediment transport in coastal environments is a fundamental goal shared by coastal scientists, engineers, and resource managers. Historical photographic analysis and predictive computer models have served as the primary approaches to charactering long-term trends in sediment flux. Net sediment grain-size trend analysis is an empirical, sedimentologically based technique that uses physical sediment samples to identify long-term sediment transport pathways. Originally developed by McLaren and Bowles (1985), net sediment grain-size trend analysis identifies progressive trends in grain-size parameters (mean size, sorting, and skewness) in sediment samples. Ultimately, the results give an indication of long-shore sediment transport, a visualization of individual littoral cells, and a better understanding of sediment processes in the near- shore region. We applied two methodologies put forth by Gao and Collins (1992) and Roux (1994) to 214 samples collected off Lanikai Beach, Hawaii; an excellent example of a coastal environment with chronic beach erosion. The Gao methodology searches point-to-point search for the two trend types used by McLaren. The Roux methodology simultaneously searches between five adjacent points for four trend types. Despite significant differences, similar trends dominate in both sets of results. The Gao methodology produces generalized trends while the Roux methodology shows finer details of sediment transport. Long-shore transport direction is shown to be northward for the majority of the study area, implying a sediment supply to the south. Therefore erosion is instigated if the sediment supply south of Lanikai Beach is cut off. A strong onshore sediment transport trend fails to accrete a beach in an armored section of the southern Lanikai coastline, demonstrating the erosive effect of increased wave refraction from coastal armoring. Results of the sediment trend analyses agree well with tidal current models

  15. Littoral sedimentation of rift lakes: an illustrated overview from the modern to Pliocene Lake Turkana (East African Rift System, Kenya)

    NASA Astrophysics Data System (ADS)

    Schuster, Mathieu; Nutz, Alexis

    2015-04-01

    Existing depositional models for rift lakes can be summarized as clastics transported by axial and lateral rivers, then distributed by fan-deltas and/or deltas into a standing water body which is dominated by settling of fine particles, and experiencing occasional coarser underflows. Even if known from paleolakes and modern lakes, reworking of clastics by alongshore drift, waves and storms are rarely considered in depositional models. However, if we consider the lake Turkana Basin (East African Rift System, Kenya) it is obvious that this vision is incomplete. Three representative time slices are considered here: the modern Lake Turkana, the Megalake Turkana which developed thanks to the African Humid Period (Holocene), and the Plio-Pleistocene highstand episodes of paleolake Turkana (Nachukui, Shungura and Koobi Fora Formations, Omo Group). First, remarkable clastic morphosedimentary structures such as beach ridges, spits, washover fans, lagoons, or wave-dominated deltas are very well developed along the shoreline of modern lake Turkana, suggesting strong hydrodynamics responsible for a major reworking of the fluvial-derived clastics all along the littoral zone (longshore and cross-shore transport) of the lake. Similarly, past hydrodynamics are recorded from prominent raised beach ridges and spits, well-preserved all around the lake, above its present water-level (~360 m asl) and up to ~455 m. These large-scale clastic morphosedimentary structures also record the maximum extent of Megalake Turkana during the African Humid Period, as well as its subsequent regression forced by the end of the Holocene climatic optimum. Several hundreds of meters of fluvial-deltaic-lacustrine deposits spanning the Pliocene-Pleistocene are exposed in the Turkana basin thanks to tectonic faulting. These deposits are world famous for their paleontological and archeological content that documents the very early story of Mankind. They also preserve several paleolake highstand episodes with

  16. High Temperature Superconducting Degaussing-Cooling Two Hts Coils with One Cryocooler for the Littoral Combat Ship

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, B. K.; Golda, E. M.; Kephart, J. T.

    2008-03-01

    The concept of creating a high temperature superconducting degaussing system has previously been studied by the Navy and shown to provide significant weight savings over conventional copper based degaussing systems. Modeling efforts have shown that in a HTS Degaussing System (HTSDG) for the Littoral Combat Ship, the dominant costs are cryocoolers. In an effort to minimize the number of cryocoolers, a two coil demonstrator cooled by one cryocooler has been constructed at NSWCCD Philadelphia. The demonstration consists of two 22 m long sections of flexible cryostat that are electrically isolated but connected in series through two junction boxes for serial gas flow. Within each cryostat section, 12 turns of HTS represent a vertical and horizontal degaussing coil. Use of Helium as the working fluid reduces safety impacts and allows higher current density in the HTS conductor due to lower temperature operation. Design, testing results, and lessons learned from the installation and operation of this cable are presented in this paper.

  17. Distribution and Ecology of Cyanobacteria in the Rocky Littoral of an English Lake District Water Body, Devoke Water

    PubMed Central

    Pentecost, Allan

    2014-01-01

    Cyanobacteria were sampled along two vertical and two horizontal transects in the littoral of Devoke Water, English Lake District. Profiles of cyanobacterium diversity and abundance showed that both attained a maximum close to the water line, but declined rapidly 20–40 cm above it. The distribution of individual species with height together with species and site ordinations showed that several taxa occurred in well-defined zones. A narrow “black zone” in the supralittoral was colonised mainly by species of Calothrix, Dichothrix and Gloeocapsa with pigmented sheaths. There was no evidence of lateral variation of species around the lake, but the height of the black zone correlated positively with wind exposure. The flora of Devoke Water is that of a base-poor mountain lake with some elements of a lowland, more alkaline water-body. PMID:25522253

  18. Vertical zonation is the main distribution pattern of littoral assemblages on rocky shores at a regional scale

    NASA Astrophysics Data System (ADS)

    Chappuis, Eglantine; Terradas, Marc; Cefalì, Maria Elena; Mariani, Simone; Ballesteros, Enric

    2014-06-01

    Vertical variation in the distribution of rocky shore assemblages is greater than horizontal variation, as shown by univariate and multivariate analysis performed with data obtained along 1000 km of shoreline and covering from the upper supralittoral to the upper infralittoral zone (-1 m). Consequently, vertical littoral zonation is a consistent pattern at a regional scale within the same biogeographical zone. While their distribution varies at the same shore height, marine species and assemblages from rocky shores show a specific vertical sequence known as zonation. A key question in ecology is how consistent is zonation along large spatial scales. The aim of this study is to show distribution patterns of littoral assemblages at a regional scale and to identify the most relevant abiotic factors associated to such patterns. The study is based on a detailed and extensive survey at a regional scale on a tideless rocky shore. Benthic macroflora and macrofauna of 750 relevés were described along the vertical axis of 143 transects distributed across the shoreline of Catalonia (NW Mediterranean). The Detrended Correspondence Analysis (DCA) first axis is highly related to the height on the shore: species, relevés, and assemblages grade from lower to upper height (infralittoral to supralittoral). As observed in nature, different assemblages co-occur at the same height at different sites, which is shown along DCA second axis. The abiotic variables that best explain the assemblage distribution patterns are: height (75% of the model inertia), longitude (14.6%), latitude (7.2%) and transect slope (2.9%). The Canonical Correspondence Analysis (CCA) first axis is related to height on the shore and explains four times more variance than CCA second axis, which is related to the horizontal gradient. Generalized Lineal Model (GLM) results show that height on the shore is the factor explaining most of the variance in species presence. Most studied species show distribution patterns

  19. Influence of abiotic factors on cathemeral activity: the case of Eulemur fulvus collaris in the littoral forest of Madagascar.

    PubMed

    Donati, Giuseppe; Borgognini-Tarli, Silvana M

    2006-01-01

    The role environmental factors play in influencing circadian rhythms in natural habitats is still poorly described in primates, especially for those taxa with an activity cycle extended over the 24-hour cycle. In this paper, we elucidate the importance of abiotic factors in entraining the activity of cathemeral primates, focussing on results from a long-term study of Eulemur fulvus collaris (collared brown lemur) in south-eastern Malagasy littoral forest. Two groups of lemurs were followed for 60 whole-day and 59 whole-night observation periods over 14 months. Diurnal and nocturnal observations were equally distributed among moon phases and seasons. Temperature and humidity were recorded hourly by automatic data loggers. The littoral forest has a climatic environment where rainfall and humidity are uncorrelated with temperature and photoperiod. Diurnal and nocturnal activity varied seasonally, with the former increasing significantly with extended day length and the latter increasing significantly with shortened day length. Dusk seemed to act as a primary zeitgeber for these lemurs, coordinating the onset of evening activity throughout the entire year. Lunar phase and the nocturnal luminosity index correlated positively with the duration of nocturnal activity and negatively with the length of diurnal activity. Temperature was positively associated with diurnal activity but did not seem to influence lemur rhythms at night. Finally, lemur nocturnal activity significantly decreased when levels of humidity and rainfall were high. Cathemeral biorhythm is triggered by zeitgebers and influenced by masking factors. The activity of collared brown lemurs appears to be seasonally influenced by photoperiod and directly modulated by nocturnal ambient luminosity. These results are discussed by comparing data from other cathemeral species living in various climatic situations. PMID:16415580

  20. From Kings Peak to the Delgado submarine canyon: Tracking littoral inputs to the deep sea at the Mendocino Triple Junction, California

    NASA Astrophysics Data System (ADS)

    Davidson, C. J.; Di Fiori, R. V.; Smith, M. E.; Mueller, E. R.

    2011-12-01

    Gravel coarse enough to overcome viscous damping and impact bedrock underwater is thought prerequisite for incision of submarine canyons, yet with few exceptions, canyons off the California coast have headwalls >2 km offshore at the shelf edge and below storm wave base. This suggests effective disconnection from modern coarse littoral sediment fluxes, and implies they are relict Pleistocene features only actively incised during glacial periods. North of the Transverse Ranges only five submarine canyons approach shore closer than 500 m, and are coincident areas of rapid uplift. Although canyons occur adjacent to major upland-draining streams that transport coarse sediment, submarine canyon headwalls are often laterally offset from stream mouths by ~1-2 km. Coarse stream sediment thus requires littoral transport to enter canyon heads and induce incision. To better understand the evolution of coarse sediment through the littoral system, we measured the texture and composition of coarse sediment in streams and beaches directly onshore of the Delgado submarine canyon, which lies offshore of the fastest uplifting segment of the King Range and onshore the Mendocino Triple Junction. Adjacent to the Delgado Canyon inlet, coarse (d50 > 360 mm) sediment enters the littoral zone from three streams, and is transported alongshore in a predominantly southeast direction. Stream-derived alluvium is comprised of a poorly to moderately sorted mixture of angular to subrounded clasts of well-cemented sandstone (d50 = 256-725 mm) and fissile siliciclastic mudstone (d50 = 90-256 mm). Well sorted and rounded beach gravels adjacent to stream mouths are similarly coarse, and clasts larger than 1 m diameter extend 200-400 meters eastward from stream mouths. In contrast, sediment entering the littoral zone from hillslope erosion between streams is finer (d50 ~16 mm) and is exclusively comprised of pervasively-folded siliciclastic mudstone. Immediately adjacent the Delgado canyon headwall

  1. Spatial and Seasonal CH4 Flux in the Littoral Zone of Miyun Reservoir near Beijing: The Effects of Water Level and Its Fluctuation

    PubMed Central

    Yang, Meng; Geng, Xuemeng; Grace, John; Lu, Cai; Zhu, Yi; Zhou, Yan; Lei, Guangchun

    2014-01-01

    Wetlands, and especially their littoral zones, are considered to be CH4 emissions hotspots. The recent creation of reservoirs has caused a rapid increase in the area of the world’s littoral zones. To investigate the effects of water depth and water level fluctuation on CH4 fluxes, and how these are coupled with vegetation and nutrients, we used static closed chamber and gas chromatography techniques to measure CH4 fluxes in the littoral zone of a large reservoir near Beijing, China, from November 2011 to October 2012. We found that CH4 flux decreased significantly along a transect from open water to dry land, from 3.1 mg m−2 h−1 at the deep water site to approximately 1.3 mg m−2 h−1 at the shallow water site, and less than 0.01 mg m−2 h−1 in the non-flooded area. Water level influenced CH4 flux by affecting soil properties including soil redox potential, soil carbon and nitrogen, and bulk density. The largest emission of all was from the seasonally flooded site after a flooding event (up to 21.1 mg m−2 h−1), which may have been caused by vegetation decomposition. Submerged sites had greater emissions, while the driest site had lower emissions. Immediately after the monthly measurements had been made, we removed the aboveground vegetation to enable an assessment of the gas transportation per unit of biomass. Removal of biomass decreased emissions by up to 53%. These results indicated the dominant effect of water depth on CH4 flux through effects of soil conditions, plant species composition and distribution. This study suggests that temporally flooded wetlands, including littoral zones, contribute significantly to the global CH4 burden. However, the current challenge is to capture their spatial extent and temporal variation in the fluxes. PMID:24710279

  2. Spatial and seasonal CH4 flux in the littoral zone of Miyun Reservoir near Beijing: the effects of water level and its fluctuation.

    PubMed

    Yang, Meng; Geng, Xuemeng; Grace, John; Lu, Cai; Zhu, Yi; Zhou, Yan; Lei, Guangchun

    2014-01-01

    Wetlands, and especially their littoral zones, are considered to be CH4 emissions hotspots. The recent creation of reservoirs has caused a rapid increase in the area of the world's littoral zones. To investigate the effects of water depth and water level fluctuation on CH4 fluxes, and how these are coupled with vegetation and nutrients, we used static closed chamber and gas chromatography techniques to measure CH4 fluxes in the littoral zone of a large reservoir near Beijing, China, from November 2011 to October 2012. We found that CH4 flux decreased significantly along a transect from open water to dry land, from 3.1 mg m(-2) h(-1) at the deep water site to approximately 1.3 mg m(-2) h(-1) at the shallow water site, and less than 0.01 mg m(-2) h(-1) in the non-flooded area. Water level influenced CH4 flux by affecting soil properties including soil redox potential, soil carbon and nitrogen, and bulk density. The largest emission of all was from the seasonally flooded site after a flooding event (up to 21.1 mg m(-2) h(-1)), which may have been caused by vegetation decomposition. Submerged sites had greater emissions, while the driest site had lower emissions. Immediately after the monthly measurements had been made, we removed the aboveground vegetation to enable an assessment of the gas transportation per unit of biomass. Removal of biomass decreased emissions by up to 53%. These results indicated the dominant effect of water depth on CH4 flux through effects of soil conditions, plant species composition and distribution. This study suggests that temporally flooded wetlands, including littoral zones, contribute significantly to the global CH4 burden. However, the current challenge is to capture their spatial extent and temporal variation in the fluxes. PMID:24710279

  3. Responses of N2O flux to water level fluctuation and other environmental factors at littoral zone of Miyun Reservoir: a comparison with CH4 fluxes

    NASA Astrophysics Data System (ADS)

    Yang, M.; Geng, X. M.; Grace, J.; Jia, Y. F.; Liu, Y. Z.; Jiao, S. W.; Shi, L. L.; Lu, C.; Zhou, Y.; Lei, G. C.

    2015-04-01

    There have been only a few studies that allow us to estimate the contribution of newly-created reservoirs to greenhouse gas budgets. In particular, information is limited for understanding the spatiotemporal variation of N2O flux and the underlying mechanisms in the littoral zone where complex biochemical processes are induced by water level fluctuations. A study was carried out at five different water levels (deep water area, shallow water area, seasonally flooded area, control site for seasonally flooded area and non-flooded area) at the littoral zone of a temperate reservoir using the static chamber technique. Seasonal and spatial variations of N2O flux and environmental factors were monitored throughout the growing season including a flood event during summer rains. The N2O flux ranged from -2.29 to 182.47 μg m-2 h-1. Non-flooded dry land emitted more N2O than flooded land, no matter whether it was permanently or seasonally flooded. However, no significant difference was observed between seasonally flooded sites and their control sites. Wind speed, air temperature, soil water content, dissolved oxygen in water and soil nitrate influenced N2O flux significantly. In order to know the contrasting characteristics of N2O and CH4 fluxes in the littoral zone of the reservoir, results were compared with a previous study on CH4 emission carried out at the same sites and time with comparable methods. It showed that N2O flux and CH4 flux was influenced by distinct factors and in differing ways. This work highlights the complexity of N2O flux at the littoral zone. The different response ways of N2O and CH4 to environments implies the big challenge of greenhouse gas emission control through ecosystem management.

  4. Methane and nitrous oxide emissions in the littoral zone of a Chinese reservoir: environmental controls and implications for future designs

    NASA Astrophysics Data System (ADS)

    Yang, Meng; Lei, Guangchun; Grace, John; Geng, Xuemeng; Lu, Cai; Zhou, Yan; Zhu, Yi

    2015-04-01

    We report fluxes of CH4 and N2O using the static closed chamber and gas chromatography techniques from the littoral zone of Miyun Reservoir, a large reservoir providing water for Beijing. Seasonal and spatial variations of CH4 and N2O flux and environmental factors were monitored throughout the growing season including a flood event during summer rains. The littoral zone was divided into five areas based on water level. Sites were selected ranging from locations in open water to the dry area on higher ground, to provide five contrasting environments: deep water area, shallow water area, seasonal flooded area, 'seasonally flooded control' area and permanent non-flooded area. Our results showed that flooding increased CH4 emission sharply but did not influence N2O emission significantly. CH4 flux decreased along a transect from open water to dry land, from 3.1 mg m-2 h-1 at the deep water site to approximately 1.3 mg m-2 h-1 at the shallow water site, and less than 0.01 mg m-2 h-1 in the non-flooded area. The largest emission of all was from the seasonally flooded site after the flooding event (up to 21.1 mg m-2 h-1). N2O flux ranged from -2.97 μg m-2 h-1 to 180.06 μg m-2 h-1. Non flooded dry land emitted more N2O than flooded land, no matter whether it was permanently or seasonally flooded. No significant difference was observed between seasonally flooded sites (3.56±0.86 μg m-2 h-1) and their control sites (3.68±0.59 μg m-2 h-1). CH4 fluxes were correlated with air temperature, water depth, water dissolved oxygen, biomass and soil parameters including soil water content, bulk density, pH, total carbon, total nitrogen and NH4+. N2O fluxes were correlated with wind speed, air temperature, water dissolved oxygen, soil water content and soil NO3-. Thus the emissions of the two gases are controlled in different ways, and we discuss the possibilities of developing a spatio-temporal model to assist in the design and management of future reservoirs under a changing

  5. Subsurface Observations in a Wind-Driven Flow in Littoral Waters off the East Coast of Florida

    NASA Astrophysics Data System (ADS)

    Chernys, M.; Dhanak, M.

    2001-12-01

    Observations of distribution of currents, temperature, salinity and density over a 1km by 0.5km spatial region in littoral waters (~20m deep) off the east coast of Florida during a passage of a low-pressure atmospheric front will be described. Meteorological and ocean surface current radar (OSCR) observations clearly show the passage of a low pressure front, during April 8-9, 2000, involving a period of warm onshore winds (~10m/s) followed by one of cold offshore winds (~14m/s) over a period of around 40 hours. Subsurface current observations from a bottom-mounted acoustic Doppler current profiler (ADCP) and from an autonomous underwater vehicle (AUV) over an 18-hour period show almost co-incident shift in current direction with the corresponding shift in the wind direction, suggesting that the currents were dominantly wind driven. Dominant currents were approximately 30 degrees to the right of the wind direction, consistent with Ekman flow. The associated magnitude of the depth of the Ekman layer and supporting temperature, salinity and water density observations from the AUV and ship-based casts will be presented. Acknowledgements: The work is part of an on-going effort, supported by ONR (Program Manager: Dr Thomas Curtin), involving AUV-based subsurface observations during adverse atmospheric conditions. Other observation elements (OSCR, bottom-mounted ADCP, moored buoys) are supported by University of Miami, NSWC, Nova Southeastern University, University of South Florida and other partners of the South Florida Ocean Measurement Center.

  6. Integrated Observations From Fixed and AUV Platforms in the Littoral Zone at the SFOMC Coastal Ocean Observatory

    NASA Astrophysics Data System (ADS)

    Dhanak, M. R.

    2001-12-01

    A 12-hour survey of the coastal waters off the east coast of Florida at the South Florida Ocean Measurement Center (SFOMC) coastal ocean observatory, during summer 1999, is described to illustrate the observatory's capabilities for ocean observation. The facility is located close to the Gulf Stream, the continental shelf break being only 3 miles from shore and is therefore influenced by the Gulf Stream meanders and the instability of the horizontal shear layer at its edge. As a result, both cross-shelf and along-shelf components of currents in the littoral zone can undergo dramatic +/- 0.5 m/s oscillations. Observations of surface currents from an OSCR, and of subsurface structure from an autonomous underwater vehicle (AUV) platform, a bottom-mounted ADCP and CT-chain arrays during the survey will be described and compared. The AUV on-board sensors included upward and downward looking 1200kHz ADCP, a CTD package and a small-scale turbulence package, consisting of two shear probes and a fast-response thermistor. Prevailing atmospheric conditions were recorded at an on-site buoy. The combined observations depict flows over a range of scales. Acknowledgements: The observations from the OSCR are due to Nick Shay and Tom Cook (University of Miami), and from the bottom-mounted ADCP, CT chain arrays and the surface buoy are due to Alex Soloviev (Nova Southeastern University) and Mark Luther and Bob Weisberg (University of South Florida).

  7. Comparative ecotoxicity of interstitial waters in littoral ecosystems using Microtox{reg_sign} and the rotifer Brachionus plicatilis

    SciTech Connect

    Valls, T.A. Del; Forja, J.M.; Lubian, L.M.; Gomez-Parra, A.

    1997-11-01

    The toxic effects of sediment interstitial waters collected from seven littoral sites in the Gulf of Cadiz were tested with the Microtox assay and a 7-d Brachionus plicatilis (Rotifera) decline test. Dissolved organic carbon (DOC), nutrients (ammonia, phosphate, nitrate, nitrite, and silicate), the heavy metals (Fe, Mn, Zn, Cu, Pb, Cr, and Cd), and the linear alkylbenzensulfonate (LAS) concentrations in the interstitial water were measured. The results of assays were compared in a dose-response relationship between sites. This comparison has demonstrated a general agreement between toxicity values determined by Brachionus plicatilis and Photobacterium phosphoreum, except in the case of interstitial water toxicity from mixtures of heavy metals. Data derived from interstitial water chemistry and bioassays were assembled by multivariate statistical techniques (principal components analysis). Positive prevalence of these components in cases studied was used to establish those ranges in chemical concentrations associated with adverse effects. The interstitial water guidelines, in terms of concentrations at or below which biological effects have been shown to be minimal (mg/L), are: DOC, 12.8; phosphate, 0.28; LAS, 80.4; ammonia, 12.1: chromium, 0.0045.

  8. Estimation of canine Leishmania infection prevalence in six cities of the Algerian littoral zone using a Bayesian approach.

    PubMed

    Adel, Amel; Abatih, Emmanuel; Speybroeck, Niko; Soukehal, Abdelkrim; Bouguedour, Rachid; Boughalem, Karim; Bouhbal, Abdelmalek; Djerbal, Mouloud; Saegerman, Claude; Berkvens, Dirk

    2015-01-01

    A large-scale study on canine Leishmania infection (CanL) was conducted in six localities along a west-east transect in the Algerian littoral zone (Tlemcen, Mostaganem, Tipaza, Boumerdes, Bejaia, Jijel) and covering two sampling periods. In total 2,184 dogs were tested with an indirect fluorescent antibody test (IFAT) and a direct agglutination test (DAT). Combined multiple-testing and several statistical methods were compared to estimate the CanL true prevalence and tests characteristics (sensitivity and specificity). The Bayesian full model showed the best fit and yielded prevalence estimates between 11% (Mostaganem, first period) and 38% (Bejaia, second period). Sensitivity of IFAT varied (in function of locality) between 86% and 88% while its specificity varied between 65% and 87%. DAT was less sensitive than IFAT but showed a higher specificity (between 80% and 95% in function of locality or/and season). A general increasing trend of the CanL prevalence was noted from west to east. A concordance between the present results and the incidence of human cases of visceral leishmaniasis was observed, where also a maximum was recorded for Bejaia. The results of the present study highlight the dangers when using IFAT as a gold standard. PMID:25793942

  9. Estimation of Canine Leishmania Infection Prevalence in Six Cities of the Algerian Littoral Zone Using a Bayesian Approach

    PubMed Central

    Adel, Amel; Abatih, Emmanuel; Speybroeck, Niko; Soukehal, Abdelkrim; Bouguedour, Rachid; Boughalem, Karim; Bouhbal, Abdelmalek; Djerbal, Mouloud; Saegerman, Claude; Berkvens, Dirk

    2015-01-01

    A large-scale study on canine Leishmania infection (CanL) was conducted in six localities along a west-east transect in the Algerian littoral zone (Tlemcen, Mostaganem, Tipaza, Boumerdes, Bejaia, Jijel) and covering two sampling periods. In total 2,184 dogs were tested with an indirect fluorescent antibody test (IFAT) and a direct agglutination test (DAT). Combined multiple-testing and several statistical methods were compared to estimate the CanL true prevalence and tests characteristics (sensitivity and specificity). The Bayesian full model showed the best fit and yielded prevalence estimates between 11% (Mostaganem, first period) and 38% (Bejaia, second period). Sensitivity of IFAT varied (in function of locality) between 86% and 88% while its specificity varied between 65% and 87%. DAT was less sensitive than IFAT but showed a higher specificity (between 80% and 95% in function of locality or/and season). A general increasing trend of the CanL prevalence was noted from west to east. A concordance between the present results and the incidence of human cases of visceral leishmaniasis was observed, where also a maximum was recorded for Bejaia. The results of the present study highlight the dangers when using IFAT as a gold standard. PMID:25793942

  10. The influence of oceanographic fronts and early-life-history traits on connectivity among littoral fish species

    PubMed Central

    Galarza, Juan A.; Carreras-Carbonell, Josep; Macpherson, Enrique; Pascual, Marta; Roques, Severine; Turner, George F.; Rico, Ciro

    2009-01-01

    The spatial distribution of neutral genetic diversity is mainly influenced by barriers to dispersal. The nature of such barriers varies according to the dispersal means and capabilities of the organisms concerned. Although these barriers are often obvious on land, in the ocean they can be more difficult to identify. Determining the relative influence of physical and biotic factors on genetic connectivity remains a major challenge for marine ecologists. Here, we compare gene flow patterns of 7 littoral fish species from 6 families with a range of early-life-history traits sampled at the same geographic locations across common environmental discontinuities in the form of oceanic fronts in the Western Mediterranean. We show that these fronts represent major barriers to gene flow and have a strong influence on the population genetic structure of some fish species. We also found no significant relation between the early-life-history traits most commonly investigated (egg type, pelagic larval duration, and inshore-offshore spawning) and gene flow patterns, suggesting that other life-history factors should deserve attention. The fronts analyzed and the underlying physical mechanisms are not site-specific but common among the oceans, suggesting the generality of our findings. PMID:19164518

  11. Long-term fate and bioavailability of sediment associated 2,3,7,8-tetrachlorodibenzofuran in littoral enclosures

    SciTech Connect

    Currie, R.S.; Fairchild, W.L.; Holoka, M.H.; Muir, D.C.G.

    2000-06-01

    the fate and bioavailability of 2,3,7,8-tetrachlorodibenzofuran (TCDF; 4,6-tritium labeled) was examined over a 3-year period in littoral enclosures in a small oligotrophic lake in the Experimental Lakes Area. Tetrachlorodibenzofuran was added as a single dose or as five small multiple additions over a 5-d period in a sediment slurry. Tetrachlorodibenzofuran was rapidly redistributed, mainly to bottom sediments reflecting removal on settling particles. Between 0 and 120 d. 80 to 90% of TCDF in the water column was associated with particles (>1 {micro}m). The highest concentration of TCDF in suspended particles was consistently observed in the smallest size fraction (0.22--1 {micro}m) at 326 to 464 d post treatment. Mode of addition had no effect on TCDF concentrations in water or surficial sediments or pore waters throughout the experiment. Mean TCDF concentrations in surficial sediment were 1.830 {+-} 1.180 pg/g whereas they averaged 1.260 {+-} 596 pg/g OC from 318 to 851 d post treatment. Increasing concentrations of TCDE in lower sediment layers at 952 d suggests that TCDF was either diffusing into the sediment or undergoing burial. Fugacity (f) calculations indicated that the TCDF in enclosures shifted from disequilibrium favoring the water column to a disequilibrium with respect to bottom sediments from day 21 onward. Initially, TCDF was more bioavailable to filtering and deposit feeders (mussels, Chironomidae, Hexagenia sp., and zooplankton) in enclosures receiving multiple additions; however, differences were rarely statistically significant. Concentrations of TCDF in all organisms were initially high, and they decreased in later sampling periods. Biota--sediment-accumulation factors (BSAFs) in mussels and crayfish were >1 in the early sampling periods, which reflected greater bioavailability of the added particle-borne TCDF. By 851 d, BSAFs had declined to 0.02 to 0.04, reflecting removal of TCDF from the water column and from surficial sediments.

  12. [The determinants of the low case fatality rate of the cholera epidemic in the Littoral department of Benin in 2008].

    PubMed

    Gbary, Akpa Raphaël; Sossou, Roch Aristide; Dossou, Jean-Paul; Mongbo, Virginie; Massougbodji, Achille

    2011-01-01

    The 2008 cholera outbreak in Benin was characterized by a low case fatality rate (0.39 p.100) in the Littoral department, where 502 cases were recorded between July and December. The aim of this study was to identify the key factors associated with the low case fatality rate within the department. The cross-sectional, descriptive and analytical study conducted as part of this research used 404 patient records, focus group discussions with ten former patients, in-depth interviews with 8 health authorities involved in the response and structured face-to-face interviews with 12 health personnel involved in the treatment of patients. The data were analyzed using qualitative and quantitative content analysis based on EPIINFO 3.3.2 and EXCEL 2007 software. The results from several sources were cross-checked through triangulation. The mean age of patients was 23.72 ± 14.8 years. 39.35% patients were admitted with severe dehydration. Oral rehydration, intravenous rehydration and antibiotic therapy were given to 99.5%, 85% and 97.77% of patients, respectively. Only one hospital death was noted. The low case fatality rate was mainly due to the following factors: the high quality of care provided in a center with qualified personnel and available and free of charge treatment kits, protocols based on massive rehydration and appropriate hygiene measures, and patient compliance with the treatment plan. The response was also characterized by good coordination, wide mass and local health promotion, and selective antibiotic prophylaxis, which contributed significantly to reducing the spread of the infection. PMID:22177702

  13. Diversity of larvae of littoral Chironomidae (Diptera: Insecta) and their role as bioindicators in urban reservoirs of different trophic levels.

    PubMed

    Morais, S S; Molozzi, J; Viana, A L; Viana, T H; Callisto, M

    2010-11-01

    The Chironomidae (Diptera: Insecta) have a high species richness, with species adapted to live under widely different environmental conditions. The study of the taxonomic composition of chironomid larvae and the percentage of occurrence of deformities in mouthparts, mainly in the mentum, are used in biomonitoring programmes in order to obtain information on the levels of organic and chemical pollution of aquatic ecosystems. The objective of this study was to evaluate the abundance of chironomid larvae and to quantify the occurrence of mentum deformities in the specimens collected in three urban reservoirs with different trophic levels. The reservoirs are located in the hydrographic basin of the Paraopeba River, an affluent of the São Francisco River basin (Minas Gerais State, southeastern Brazil). The Serra Azul Reservoir is oligotrophic, the Vargem das Flores Reservoir is mesotrophic, and the Ibirité Reservoir is eutrophic. Along the littoral zone of each reservoir, 30 samples were collected during each sampling campaign. Sampling was carried out every three months for one year, with two sampling campaigns during the wet season and two during the dry season in 2008. Physical and chemical parameters measured in the water column included the water depth, Secchi depth, air and water temperature, electrical conductivity, total dissolved solids, redox potential, dissolved oxygen, pH, turbidity, Total-N, Total-P, P-ortho, and chlorophyll-a. The chironomid larvae were identified to the genus level. The structure of the chironomid assemblages was evaluated based on taxonomic richness (24 genera), density, equitability, and diversity. The potential indicator taxa for each reservoir were established through an Indicator Species Analysis. The values for taxonomic richness (20 taxa), equitability (0.737), and Shannon-Wiener diversity (2.215) were highest in the Serra Azul Reservoir. Fissimentum was the indicator taxon in Serra Azul, the oligotrophic reservoir; whereas

  14. Mavale project: Sensor techniques applied to macrozoning of the Paraiba Valley and littoral north of the State of Sao Paulo

    NASA Astrophysics Data System (ADS)

    1991-04-01

    This project was designed with two basic objectives in mind. The first is to support the Consortium for Integrated Development of the Paraiba Valley and the Northern Littoral (CODIVAP) for preparation of regulatory guidelines for use of the regional lands. The second is to place at the disposal of the country's technical/scientific community a regional planning method based on the use of Remote Orbital Sensor data. This project involved studies on the following areas: maps - geological, pedological, geomorphological, ground cover, land use, urban area and urban expansion in the last decade, areas favorable for replenishment and concentration of ground water; compartmentation of the region into sub-basins and study of the relationships of land use to surface water quality; generation of a map indicating the suitability of land for civil engineering and urban expansion projects and projects subject to geological risk; preparation of a map showing suitability for agricultural use of the land; and social/economic/demographic analysis. The region of the study encompasses 40 municipalities and portions of 4 others, in an overall region of 18.111 sq. km. Imagery from MSS/Landsat, TM/Landsat, and HRV/SPOT was interpreted, exploring the multispectral, multitemporal, synoptic characteristics as well as the detail (compatible with spatial resolutions of the sensor systems). As a function of the objectives of the different thematic studies involved in the environmental and physical diagnostics, images were interpreted visually or processed digitally in alternate scales of 1:250,000, 1:100,000, or 1:50,000. These studies were complemented with pre-existing bibliographical and cartographic information, and the final mapping products are presented to the scale of 1:250,000, compatible with decisions at the regional level. Thematic studies relative to the physical/territorial, and social/economical reality were integrated in the search for holistic understanding of the region and

  15. Lead isotopes in soils and groundwaters as tracers of the impact of human activities on the surface environment: The Domizio-Flegreo Littoral (Italy) case study

    USGS Publications Warehouse

    Grezzi, G.; Ayuso, R.A.; de Vivo, B.; Lima, A.; Albanese, S.

    2011-01-01

    The isotopic signature of geogenic and anthropogenic materials, in combination with concentration data for pollutants, can help trace the origin and the extent of contamination in the environment. This approach is particularly effective if naturally occurring and anthropogenically introduced metals have different isotopic ratios. Lead isotope analysis on soils from 7 profiles (1. m depth) and on groundwaters from 8 wells have been used to determine the impact of human activities on the surface environment of Domizio-Flegreo Littoral. Result obtained show that in sub-rural areas the isotopic composition of the samples collected along the soil profiles of Domizio-Flegreo Littoral is likely mostly controlled by the nature of the parent geologic material (natural) while in more urbanized areas (Giugliano) Pb isotopic composition in superficial soils is mostly influenced by anthropic sources such as motor vehicles. Lead isotopic ratios in groundwaters also show that the use of pesticides and, probably, the influence of aerosols and the presence of illegal waste disposal can influence water quality. ?? 2010 Elsevier B.V.

  16. Influence of the very polluted inputs of the Tinto-Odiel system on the adjacent littoral sediments of southwestern Spain: a statistical approach.

    PubMed

    Sainz, A; Ruiz, F

    2006-03-01

    A spatial and temporal analysis (period 1990-2003) of 15 sampling points distributed along the southwestern Spanish coast permits to delimitate the influence area of the extremely polluted discharges coming from the Tinto-Odiel system in the bottom sediments of the adjacent littoral area. As, Cu, Pb and Zn are the main heavy metals transported by the freshwater runoffs toward the shallow shelf and present very high negative (r < -0.7) and significant (p < 0.001) correlations with the distance to the estuarine mouth. The statistical analysis (index of geoaccumulation, Pearson correlation matrix, cluster analysis) of their concentrations in the littoral sediments located between the Guadiana and Guadalquivir mouths delimitates three zones: (a) Zone 1 (from the estuarine mouth to 6 km to the east), characterized by moderate to strongly polluted bottom sediments and main responsible of the mean annual variations of the former heavy metals in the area studied; (b) Zone 2 (from 21.2 km to the west to 29 km to the east), characterized by moderate pollution levels; and (c) Zone 3, located near the Guadiana and Guadalquivir mouths, with very low As-Cu-Pb contents and unpolluted to moderately levels of Zn due to urban sewages or the presence of local low mobility areas for this element. PMID:16122777

  17. Diurnal behavior of the carbon dioxide flux and change in the isotopic ratio δ13C in surface and near-bottom water in littoral of Lake Baikal

    NASA Astrophysics Data System (ADS)

    Panchenko, Mikhail V.; Domysheva, Valentina M.; Padalko, Natalia L.; Chernikov, Eugenii V.; Prazdnichnykh, Maxim I.; Tumakov, Alexander G.; Pestunov, Dmitrii A.

    2014-11-01

    Lake Baikal is one of the unique natural environments in Siberia which, to a large extent, affects the state of the nature in this region. The processes of gas exchange in the "water-atmosphere" system have been studied in Lake Baikal since 2002. The main purpose of the integrated investigations of exchange of carbon-containing gases in the water-atmosphere system in Lake Baikal is to study the contribution of physical, chemical, and biological components of the process and their interrelation with the intensity and rhythms of the fluxes. In 2013, the integrated measurements in the littoral area of Baikal were complemented with studies of the diurnal dynamics of isotopic ratio δ 13C in the surface and near-bottom water, which were not yet performed in Baikal before. In this work, we analyze first results of the joint analysis of RO2 fluxes in the "atmosphere - water surface" system and δ 13C, obtained in August 2013 in the littoral area of South Baikal. It is shown that d13C markedly increases in the surface waters at daylight time. In nighttime period, there takes place a reverse process, when δ 13C of the surface water approaches δ 13C, which is recorded for near-bottom water.

  18. The remote sensing of aquatic macrophytes Part 1: Color-infrared aerial photography as a tool for identification and mapping of littoral vegetation. Part 2: Aerial photography as a quantitative tool for the investigation of aquatic ecosystems. [Lake Wingra, Wisconsin

    NASA Technical Reports Server (NTRS)

    Gustafson, T. D.; Adams, M. S.

    1973-01-01

    Research was initiated to use aerial photography as an investigative tool in studies that are part of an intensive aquatic ecosystem research effort at Lake Wingra, Madison, Wisconsin. It is anticipated that photographic techniques would supply information about the growth and distribution of littoral macrophytes with efficiency and accuracy greater than conventional methods.

  19. Characterization of lake water and ground water movement in the littoral zone of Williams Lake, a closed-basin lake in North central Minnesota

    USGS Publications Warehouse

    Schuster, P.F.; Reddy, M.M.; LaBaugh, J.W.; Parkhurst, R.S.; Rosenberry, D.O.; Winter, T.C.; Antweiler, R.C.; Dean, W.E.

    2003-01-01

    Williams Lake, Minnesota is a closed-basin lake that is a flow-through system with respect to ground water. Ground-water input represents half of the annual water input and most of the chemical input to the lake. Chemical budgets indicate that the lake is a sink for calcium, yet surficial sediments contain little calcium carbonate. Sediment pore-water samplers (peepers) were used to characterize solute fluxes at the lake-water-ground-water interface in the littoral zone and resolve the apparent disparity between the chemical budget and sediment data. Pore-water depth profiles of the stable isotopes ??18O and ??2H were non-linear where ground water seeped into the lake, with a sharp transition from lake-water values to ground-water values in the top 10 cm of sediment. These data indicate that advective inflow to the lake is the primary mechanism for solute flux from ground water. Linear interstitial velocities determined from ??2H profiles (316 to 528 cm/yr) were consistent with velocities determined independently from water budget data and sediment porosity (366 cm/yr). Stable isotope profiles were generally linear where water flowed out of the lake into ground water. However, calcium profiles were not linear in the same area and varied in response to input of calcium carbonate from the littoral zone and subsequent dissolution. The comparison of pore-water calcium profiles to pore-water stable isotope profiles indicate calcium is not conservative. Based on the previous understanding that 40-50 % of the calcium in Williams Lake is retained, the pore-water profiles indicate aquatic plants in the littoral zone are recycling the retained portion of calcium. The difference between the pore-water depth profiles of calcium and ??18O and ??2H demonstrate the importance of using stable isotopes to evaluate flow direction and source through the lake-water-ground-water interface and evaluate mechanisms controlling the chemical balance of lakes. Published in 2003 by John Wiley

  20. Influence of the parameters of sweet-water flow in littoral sea zones on the dimensions of a saline-water tongue

    NASA Astrophysics Data System (ADS)

    Bereslavskii, É. N.

    2008-05-01

    Consideration is given to the model of motion of sweet groundwater in a trapezoidal pressure water-bearing stratum to a sea with saline water. For studying this model, a mixed multiparametric boundary-value problem of the theory of analytical functions is formulated and solved using the P. Ya. Polubarinova-Kochina method. The algorithm of calculation of the intrusion of seawater into the sweet-water layer in the case where its right-hand boundary modeling the littoral zone of the sea floor makes an arbitrary angle with the horizon is developed based on this scheme. The characteristic features of the modeled process and the influence of all determining physical parameters on the character and degree of intrusion are analyzed using the exact analytical dependences obtained and numerical calculations.

  1. Littoral fish assemblages of the alien-dominated Sacramento-San Joaquin Delta, California, 1980-1983 and 2001-2003

    USGS Publications Warehouse

    Brown, L.R.; Michniuk, D.

    2007-01-01

    We analyzed monthly boat electrofishing data to characterize the littoral fish assemblages of five regions of the Sacramento-San Joaquin Delta (northern, southern, eastern, western, and central), California, during two sampling periods, 1980-1983 (1980s) and 2001-2003 (2000s), to provide information pertinent to the restoration of fish populations in this highly altered estuary. During the 1980s, almost 11,000 fish were captured, including 13 native species and 24 alien species. During the 2000s, just over 39,000 fish were captured, including 15 native species and 24 alien species. Catch per unit effort (CPUE) of total fish, alien fish, and centrarchid fish were greater in the 2000s compared with the 1980s, largely because of increased centrarchid fish CPUE. These differences in CPUE were associated with the spread of submerged aquatic vegetation (SAV), particularly an alien aquatic macrophyte Egeria densa. Native fish CPUE declined from the 1980s to the 2000s, but there was no single factor that could explain the decline. Native fish were most abundant in the northern region during both sampling periods. Nonmetric multidimensional scaling indicated similar patterns of fish assemblage composition during the two sampling periods, with the northern and western regions characterized by the presence of native species. The separation of the northern and western regions from the other regions was most distinct in the 2000s. Our results suggest that native fish restoration efforts will be most successful in the northern portion of the Delta. Management decisions on the Delta should include consideration of possible effects on SAV in littoral habitats and the associated fish assemblages and ecological processes. ?? 2007 Estuarine Research Federation.

  2. Aspects histo-épidémiologiques des cancers génitaux de la femme dans la région du Littoral, Cameroun

    PubMed Central

    Engbang, Jean Paul Ndamba; Koh, Valère Mve; Tchente, Charlotte Nguefack; Fewou, Amadou

    2015-01-01

    Décrire les caractéristiques épidémiologiques et histopathologiques des tumeurs malignes génitales de la femme dans la région du littoral du Cameroun. Il s'agissait d'une étude rétrospective descriptive et analytique portant sur les cancers des organes génitaux de la femme, histologiquement prouvés pendant une période de 10 ans (2004-2013), répertoriés dans les registres des trois laboratoires d'anatomopathologie de la région (Hôpital Laquintinie de Douala, Hôpital Général de Douala, laboratoire Anapathos) et des services d'oncologie de ces hôpitaux. Les variables étudiées étaient: la fréquence, l’âge, le sexe, la localisation de la tumeur et le type histopathologique. Au total, 802 cas de cancers génitaux de la femme ont été recensés, soit une fréquence annuelle de 80,2 cas en moyenne. Le col utérin avec 580 cas (72,32%) a été la localisation la plus fréquente; suivi de l'endomètre (corps utérin) avec 93 cas (11,60%), puis des ovaires 91 cas (11,35%). L’âge moyen des patientes était de 50, 30±12,67 ans, avec les extrêmes allant de 14 à 85 ans. Selon le type histologique, les tumeurs épithéliales ont été les plus fréquemment rencontrées, soit 758 patientes (94,51%), les lymphomes venaient en seconde position avec 29 cas (3, 62%), les autres variétés histologiques (sarcomes, tumeurs germinales, tumeurs du mésenchyme et du cordon) représentant moins chacune de 1%. Les tumeurs malignes des organes génitaux féminins sont fréquentes dans la région du littoral du Cameroun, elles sont dominées essentiellement par le cancer du col utérin. Les tumeurs épithéliales sont le type histologique le plus fréquent. PMID:26327953

  3. The influence of a toxic cyanobacterial bloom and water hydrology on algal populations and macroinvertebrate abundance in the upper littoral zone of Lake Krugersdrift, South Africa.

    PubMed

    Oberholster, Paul J; Botha, Anna-Maria; Ashton, Peter J

    2009-01-01

    The biological interactions and the physical and chemical properties of the littoral zone of Lake Krugersdrift were studied for a 4-month period when a dense, toxic cyanobacterial bloom dominated by Microcystis aeruginosa was present in the main lake basin. The presence of a toxic strain of M. aeruginosa was confirmed through the use of ELISA and molecular markers that detect the presence of the mcyB and mcyD genes of the mcy gene cluster that synthesizes microcystin. An increase in Microcystis toxicity at sites dominated by the cyanobacterial scum was accompanied by an increase in total abundance of the macroinvertebrate families Hirudinae, Chironomidae, and Tubificidae. Sites located away from the cyanobacterial scum had a lower abundance but a higher diversity of macroinvertebrates. The water quality under the Microcystis scum was characterized by low pH values, low concentrations of dissolved oxygen, and lower total alkalinity values. The periphytic alga Ulothrix zonata was absent in areas dominated by the cyanobacterial scum, possibly as a result of overshadowing by the scum or direct toxic allelopathic effects on growth and photosynthesis. The diatom Diatoma vulgare dominated the benthic algal flora beneath the cyanobacterial scum. PMID:18802748

  4. Toxic metal (Pb, Cd, Cr, and Hg) levels in Rapana venosa (Valenciennes, 1846), Eriphia verrucosa (Forskal, 1775), and sediment samples from the Black Sea littoral (Thrace, Turkey).

    PubMed

    Mülayim, A; Balkıs, H

    2015-06-15

    Rapana venosa (Valenciennes, 1846) and Eriphia verrucosa (Forskal, 1775) are the dominant benthic invertebrate species along the Thrace Coast of the western Black Sea. The aim of this study was to determine toxic metal (Hg, Cr, Cd, and Pb) accumulation levels in these species, as well as within littoral sediments from this area. Our results showed that all of the metals, except for Cd, were below that in average shale. The measured accumulation levels were mostly within the range of what is naturally found within the earth's crust. However, some study stations did have increased concentrations, indicating anthropogenic pollution in these areas. The Cd contents of E. verrucosa collected from all our study stations were well above the limits set by the Turkish Food Codex, especially in Kıyıköy, whereas Pb content was close to the limit at all stations and exceeded the limit in Kıyıköy, but Hg content was below the limit at all stations. Cd content of R. venosa exceeded the limit only in Kumköy. Pb content was below the limit, and Hg was at or slightly above the limit at all stations. PMID:25913797

  5. Neural organization of first optic neuropils in the littoral crab Hemigrapsus oregonensis and the semiterrestrial species Chasmagnathus granulatus

    PubMed Central

    Sztarker, Julieta; Strausfeld, Nicholas; Andrew, David; Tomsic, Daniel

    2014-01-01

    Crustaceans are among the most extensively distributed arthropods, occupying many ecologies and manifesting a great variety of compound eye optics; but in comparison with insects, relatively little is known about the organization and neuronal morphologies of their underlying optic neuropils. Most studies, which have been limited to descriptions of the first neuropil - the lamina - suggest that different species have approximately comparable cell types. However, such studies have been limited with regard to the types of neurons they identify and most omit their topographic relationships. It is also uncertain whether similarities, such as they are, are independent of visual ecologies. The present account describes and compares the morphologies and dispositions of monopolar and other efferent neurons as well as the organization of tangential and smaller centrifugal neurons in two grapsoid crabs, one from the S. Atlantic, the other from the N. Pacific. Because these species occupy significantly disparate ecologies we ask whether this might be reflected in differences of cell arrangements within the most peripheral levels of the visual system. The present study identifies such differences with respect to the organization of centrifugal neurons to the lamina. We also identify in both species neurons in the lamina that have hitherto not been identified in crustaceans and we draw specific comparisons between the layered organization of the grapsoid lamina and layered laminas of insects. PMID:19123235

  6. Repeated landmass reformation limits diversification in the widespread littoral zone mosquito Anopheles sundaicus sensu lato in the Indo-Oriental Region.

    PubMed

    Zarowiecki, Magdalena; Linton, Yvonne-Marie; Post, Rory J; Bangs, Michael J; Htun, Pe Than; Hlaing, Thaung; Seng, Chang Moh; Baimai, Visut; Ding, Trung Ho; Sochantha, Tho; Walton, Catherine

    2014-05-01

    Southeast Asia harbours abundant biodiversity, hypothesized to have been generated by Pliocene and Pleistocene climatic and environmental change. Vicariance between the island of Borneo, the remaining Indonesian archipelago and mainland Southeast Asia caused by elevated sea levels during interglacial periods has been proposed to lead to diversification in the littoral zone mosquito Anopheles (Cellia) sundaicus (Rodenwaldt) sensu lato. To test this biogeographical hypothesis, we inferred the population history and assessed gene flow of A. sundaicus s.l. sampled from 18 populations across its pan-Asian species range, using sequences from mitochondrial cytochrome c oxidase subunit 1 (CO1), the internal transcribed spacer 2 (ITS2) and the mannose phosphate isomerase (Mpi) gene. A hypothesis of ecological speciation for A. sundaicus involving divergent adaptation to brackish and freshwater larval habitats was also previously proposed, based on a deficiency of heterozygotes for Mpi allozyme alleles in sympatry. This hypothesis was not supported by Mpi sequence data, which exhibited no fixed differences between brackish and freshwater larval habitats. Mpi and CO1 supported the presence of up to eight genetically distinct population groupings. Counter to the hypothesis of three allopatric species, divergence was often no greater between Borneo, Sumatra/Java and the Southeast Asian mainland than it was between genetic groupings within these landmasses. An isolation-with-migration (IM) model indicates recurrent gene flow between the current major landmasses. Such gene flow would have been possible during glacial periods when the current landmasses merged, presenting opportunities for dispersal along expanding and contracting coastlines. Consequently, Pleistocene climatic variation has proved a homogenizing, rather than diversifying, force for A. sundaicus diversity. PMID:24750501

  7. Geochemical distribution of harmful elements in top soils of an Italian National Interest Area (S.I.N.): the Domizio-Flegreo Littoral and Agro Aversano case study

    NASA Astrophysics Data System (ADS)

    Bove, M.; Grezzi, G.; Albanese, S.; de Vivo, B.; Lima, A.

    2009-04-01

    The Domizio-Flegreo Littoral and Agro Aversano area has been classified by the Italian Ministry of Environment (Italian Ministero dell'Ambiente e della Tutela del Territorio e del Mare) as a S.I.N. (Sito di Interesse Nazionale, L. 426/98 - Decreto 10 Gennaio 2000 - G.U. 29/5/01). In this category have been included all those contaminated lands that, both for their extension and their historical and present land use, are considered to be particularly harmful for human health. In Italy have been selected a total of 54 S.I.N.; among all of these, the Domizio-Flegreo Littoral and Agro Aversano S.I.N. is one of the widest (1564 Km2). The study area is located in north-western Campania region, from the Avella Mountain to the coastline, and from the Campi Flegrei area to the northern boundaries between Campania and Latium Regions. It includes a total of 77 towns from both Naples and Caserta provinces. The Domizio-Flegreo Littoral and Agro Aversano S.I.N. is characterized by a strongly urbanization in its internal portions, and by intensive agricultural activities in its northern and coastal portions. During past years this wide area has been the set of an unknown number of illegal activities controlled by the organized crime, including toxic waste disposal of unknown sources from different Regions of Italy, unauthorized building, intensive uncontrolled agricultural practices and so on. Part of these environmental crimes have been and are under investigations by Italian Authorities. For a geochemical characterization of this contaminated land, between May 2006 and January 2008, a total of 292 (179 in the Litorale Domizio-Flegreo and 113 in the Agro Aversano) top soils (5-15 cm depth) have been collected, with a sampling density of about 1 sample/5 Km2. The <100 mesh soil fraction has been analyzed with ICP-MS to determine the concentration of the 39 elements: Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sn

  8. A Description of Biremis panamae sp. nov., a New Diatom Species from the Marine Littoral, with an Account of the Phylogenetic Position of Biremis D.G. Mann et E.J. Cox (Bacillariophyceae)

    PubMed Central

    Witkowski, Andrzej; Barka, Frederik; Mann, David G.; Li, Chunlian; Weisenborn, Jascha L. F.; Ashworth, Matt P.; Kurzydłowski, Krzysztof J.; Zgłobicka, Izabela; Dobosz, Sławomir

    2014-01-01

    Here we present a formal description of Biremis panamae Barka, Witkowski et Weisenborn sp. nov., which was isolated from the marine littoral environment of the Pacific Ocean coast of Panama. The description is based on morphology (light and electron microscopy) and the rbcL, psbC and SSU sequences of one clone of this species. The new species is included in Biremis due to its morphological features; i.e. two marginal rows of foramina, chambered striae, and girdle composed of numerous punctate copulae. The new species also possesses a striated valve face which is not seen in most known representatives of marine littoral Biremis species. In this study we also present the relationship of Biremis to other taxa using morphology, DNA sequence data and observations of auxosporulation. Our results based on these three sources point to an evolutionary relationship between Biremis, Neidium and Scoliopleura. The unusual silicified incunabular caps present in them are known otherwise only in Muelleria, which is probably related to the Neidiaceae and Scoliotropidaceae. We also discuss the relationship between Biremis and the recently described Labellicula and Olifantiella. PMID:25494095

  9. Testing compound-specific δ13C of amino acids in mussels as a new approach to determine the average 13C values of primary production in littoral ecosystems

    NASA Astrophysics Data System (ADS)

    Vokhshoori, N. L.; Larsen, T.; McCarthy, M.

    2012-12-01

    Compound-specific isotope analysis of amino acids (CSI-AA) is a technique used to decouple trophic enrichment patterns from source changes at the base of the food web. With this new emerging tool, it is possible to precisely determine both trophic position and δ15N or δ13C source values in higher feeding organisms. While most work to date has focused on nitrogen (N) isotopic values, early work has suggested that δ13C CSI-AA has great potential as a new tracer both to a record δ13C values of primary production (unaltered by trophic transfers), and also to "fingerprint" specific carbon source organisms. Since essential amino acids (EAA) cannot be made de novo in metazoans but must be obtained from diet, the δ13C value of the primary producer is preserved through the food web. Therefore, the δ13C values of EAAs act as a unique signature of different primary producers and can be used to fingerprint the dominant carbon (C) source driving primary production at the base of the food web. In littoral ecosystems, such as the California Upwelling System (CUS), the likely dominant C sources of suspended particulate organic matter (POM) pool are kelp, upwelling phytoplankton or estuarine phytoplankton. While bulk isotopes of C and N are used extensively to resolve relative consumer hierarchy or shifting diet in a food web, we found that the δ13C bulk values in mussels cannot distinguish exact source in littoral ecosystems. Here we show 15 sites within the CUS, between Cape Blanco, OR and La Jolla, CA where mussels were sampled and analyzed for both bulk δ13C and CSI-AA. We found no latitudinal trends, but rather average bulk δ13C values for the entire coastal record were highly consistent (-15.7 ± 0.9‰). The bulk record would suggest either nutrient provisioning from kelp or upwelled phytoplankton, but 13C-AA fingerprinting confines these two sources to upwelling. This suggests that mussels are recording integrated coastal phytoplankton values, with the enriched

  10. Optic chiasmal cavernous angioma: A rare suprasellar vascular malformation

    PubMed Central

    Abou-Al-Shaar, Hussam; Bahatheq, Ayman; Takroni, Radwan; Al-Thubaiti, Ibrahim

    2016-01-01

    Background: Suprasellar cavernous malformation in the optic pathway is not commonly encountered. To date, there are only few reports present in the literature. Case Description: The authors report a rare case of suprasellar optic pathway cavernous malformation in a 33-year-old female who presented with progressive visual loss. Her imaging revealed a large heterogeneous, hyperintense, hemorrhagic right suprasellar extra-axial complex cystic structure, causing mass effect on the adjacent hypothalamus and third ventricle displacing these structures. Gross total resection of the lesion was achieved utilizing a right frontal craniotomy approach. Histopathological examination confirmed the diagnosis of suprasellar chiasmal cavernous malformation. Conclusion: Although visual pathway cavernous malformation is a rare event, it should be included in the differential diagnosis of lesions occurring suprasellarly in the visual pathway and hypothalamus. PMID:27583178

  11. Spatio-temporal distribution of cell-bound and dissolved geosmin in Wahnbach Reservoir: Causes and potential odour nuisances in raw water.

    PubMed

    Jähnichen, Sabine; Jäschke, Kathrin; Wieland, Falk; Packroff, Gabriele; Benndorf, Jürgen

    2011-10-15

    In many lakes and reservoirs, problems caused by off-flavours are known to be particularly associated with the occurrence of planktonic and benthic cyanobacteria. Frequently observed objectionable taste and odorous products of cyanobacteria are geosmin and 2-methylisoborneol. Investigations focused on the littoral zone of Wahnbach Reservoir (Germany) revealed that benthic cyanobacteria were present in this oligotrophic drinking water reservoir. Benthic cyanobacteria were found in the depth horizon between 1.75 m and 11 m, particularly on south-exposed slopes. This spatial distribution indicates a possible key role of the underwater light climate. Moreover, cell-bound and dissolved geosmin were detected in corresponding littoral samples. Both fractions were subjected to spatial and primarily temporal variations with maximum concentrations at the end of summer. However, a substantial lowering of the water level caused a diminution of cyanobacterial growth. Due to the drawdown of the water level concentrations of cell-bound geosmin and pigments (as a proxy of cyanobacterial biomass) were remarkably reduced, and dissolved geosmin was never detected during this phase. Except for the influence of water level fluctuation no other abiotic variables had a significant influence on pigment and geosmin concentrations. From geosmin concentrations detected in the littoral zone, the probability of serious episodes of odour events in the raw water of the Wahnbach Reservoir was estimated. Hence, the probability that the raw water was affected by geosmin was minor, which was supported by routine flavour profiles. Nevertheless, the study shows that odorous episodes caused by benthic cyanobacteria are likely to develop even in an oligotrophic lake or reservoir when these cyanobacteria, and consequently odorous production, proliferate. In principle, such a proliferation cannot be excluded as nutrients are available from the sediment pore water, and underwater light at the sediment

  12. Transplantation of modified human adipose derived stromal cells expressing VEGF165 results in more efficient angiogenic response in ischemic skeletal muscle

    PubMed Central

    2013-01-01

    Background Modified cell-based angiogenic therapy has become a promising novel strategy for ischemic heart and limb diseases. Most studies focused on myoblast, endothelial cell progenitors or bone marrow mesenchymal stromal cells transplantation. Yet adipose-derived stromal cells (in contrast to bone marrow) are abundantly available and can be easily harvested during surgery or liposuction. Due to high paracrine activity and availability ADSCs appear to be a preferable cell type for cardiovascular therapy. Still neither genetic modification of human ADSC nor in vivo therapeutic potential of modified ADSC have been thoroughly studied. Presented work is sought to evaluate angiogenic efficacy of modified ADSCs transplantation to ischemic tissue. Materials and methods Human ADSCs were transduced using recombinant adeno-associated virus (rAAV) serotype 2 encoding human VEGF165. The influence of genetic modification on functional properties of ADSCs and their angiogenic potential in animal models were studied. Results We obtained AAV-modified ADSC with substantially increased secretion of VEGF (VEGF-ADSCs). Transduced ADSCs retained their adipogenic and osteogenic differentiation capacities and adhesion properties. The level of angiopoetin-1 mRNA was significantly increased in VEGF-ADSC compared to unmodified cells yet expression of FGF-2, HGF and urokinase did not change. Using matrigel implant model in mice it was shown that VEGF-ADSC substantially stimulated implant vascularization with paralleling increase of capillaries and arterioles. In murine hind limb ischemia test we found significant reperfusion and revascularization after intramuscular transplantation of VEGF-ADSC compared to controls with no evidence of angioma formation. Conclusions Transplantation of AAV-VEGF- gene modified hADSC resulted in stronger therapeutic effects in the ischemic skeletal muscle and may be a promising clinical treatment for therapeutic angiogenesis. PMID:23742074

  13. Germ-Line Mutations in the von Hippel–Lindau Tumor-Suppressor Gene Are Similar to Somatic von Hippel–Lindau Aberrations in Sporadic Renal Cell Carcinoma

    PubMed Central

    Whaley, Jean M.; Naglich, Joseph; Gelbert, Lawrence; Hsia, Y. Edward; Lamiell, James M.; Green, Jane S.; Collins, Debra; Neumann, Hartmut P. H.; Laidlaw, Jana; Li, Fred P.; Klein-Szanto, Andres J. P.; Seizinger, Bernd R.; Kley, Nikolai

    1994-01-01

    von Hippel–Lindau (VHL) disease is a hereditary tumor syndrome predisposing to multifocal bilateral renal cell carcinomas (RCCs), pheochromocytomas, and pancreatic tumors, as well as angiomas and hemangioblastomas of the CNS. A candidate gene for VHL was recently identified, which led to the isolation of a partial cDNA clone with extended open reading frame, without significant homology to known genes or obvious functional motifs, except for an acidic pentamer repeat domain. To further characterize the functional domains of the VHL gene and assess its involvement in hereditary and nonhereditary tumors, we performed mutation analyses and studied its expression in normal and tumor tissue. We identified germ-line mutations in 39% of VHL disease families. Moreover, 33% of sporadic RCCs and all (6/6) sporadic RCC cell lines analyzed showed mutations within the VHL gene. Both germ-line and somatic mutations included deletions, insertions, splice-site mutations, and missense and nonsense mutations, all of which clustered at the 3' end of the corresponding partial VHL cDNA open reading frame, including an alternatively spliced exon 123 nt in length, suggesting functionally important domains encoded by the VHL gene in this region. Over 180 sporadic tumors of other types have shown no detectable base changes within the presumed coding sequence of the VHL gene to date. We conclude that the gene causing VHL has an important and specific role in the etiology of sporadic RCCs, acts as a recessive tumor-suppressor gene, and appears to encode important functional domains within the 3' end of the known open reading frame. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:7977367

  14. Ecological state of the Romanian Black Sea littoral lacustrine ecosystems

    NASA Astrophysics Data System (ADS)

    Gomoiu, M.-T.

    2009-04-01

    The author uses the results of his own researches as well as data from specialty literature to assess the ecological state of some typical lacustrine ecosystems considered, about 50 years ago, of major importance by their functions, services and researches, for the human populations in the settlements nearby. Based on this assessment the author recommends a few criteria which can be taken into account when programs of integrated management of these coastal ecosystems are initiated. The paper focuses on the study cases regarding the following major ecosystems: 1. Razelm-Sinoie Lagoon Complex - tightly linked to the Danube River and Delta systems, 2. Taşaul Lake - interfered in the last two decades by a branch of the DanubeRiver - Black Sea Canal and 3. Techirghiol Lake - for a long time under the sea level, a hyperhaline lake with therapeutic, sapropelic mud, disturbed by huge quantities of freshwaters infiltrated from the irrigation system. At present, the state of the lacustrine ecosystems at the Romanian Black Sea Coast can be characterized, mainly, by the following aspects: · Increase in the quantities of nutrients and chemical toxicants; · Rise in the level and frequency of eutrophication and pollution phenomena; · Drastic reduction of specific diversity; · Simplification of communities' structure - biocoenosis homogeneity; · Decrease in numerical abundance and biomass of benthic populations and consequently, low biofilter power by the decrease of the filter-feeder populations; · Worsening of the qualitative and the quantitative state of the biological benthic resources; · Thriving opportunistic forms (e.g. the worms causing sediment bioturbation); · Invasion by some exotic species, with harmful, unexpected consequences; · All populations undergo quantitative fluctuations; · Decrease in the fish population and in the use values of lacustrine assets, with strong impact on the welfare of the human society. Almost all pressure forms associated with the relationship between the socio-economic systems and the other components of the hierarchy of ecological systems also existed, without exception, in the Romanian coastal part of the Black Sea causing manifest ecological effects on various types of para-marine lacustrine ecosystems. Generally, we consider that the following set of effects is typical of the ecological impact resulted from the dynamics of the socio-economic systems at different time and space scales: · Erosion of diversity as a result of the loss of species or reduction in the species abundance in the local ecosystems and complex of ecosystems or because of the habitat fragmentation, isolation of valuable natural systems, to which other causes may be added such as desertification and salinization or water freshening; · Erosion of biological diversity caused by: extinction of higher species and taxa, loss of genetic resources, increase in the number of rare species threatened with extinction and significant reduction in the ethno-cultural diversity; · Depletion or reduction in the stocks of renewable and non-renewable natural resources; · Changes in the biogeochemical cycles and in the climatic system, caused by the overloading of the surface waters and soils with nutrients, heavy metals, radio-nuclides, greenhouse gases, particulate or dissolved organic matter and by deterioration of other factors. These changes cause, in their turn, a series of processes similar to chain reactions, which lead to an increasing risk of natural disasters; · Decrease in the productive and supportive capacity of components which form the foundation of the socio-economic system in the reference zone. · An alarming increase in the „environmental debt" which endangers the chances of short-term and, especially, long-term development. The author recommends some solutions in solving the conflict of interest, which consist in a set of measures and actions, as follows: · identifying synergies or contradictions between actions resulting from various policies; · improving coordination, cooperation and consulta

  15. Seabird guano fertilizes Baltic Sea littoral food webs.

    PubMed

    Gagnon, Karine; Rothäusler, Eva; Syrjänen, Anneli; Yli-Renko, Maria; Jormalainen, Veijo

    2013-01-01

    Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis) has increased nearly exponentially since the mid-1990 s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable isotope analyses and diet mixing models to determine the extent of nitrogen enrichment from cormorant colonies, as well as to examine any possible changes in herbivore diet preferences due to enrichment. We found significantly higher levels of δ(15)N in samples from colony islands than control islands for producers (the dominant macroalga Fucus vesiculosus, filamentous algae, and periphyton) and herbivores, as well as a positive correlation between enrichment and nest density in colony sites. We also found that enrichment increased over the breeding season of the cormorants, with higher enrichment in late summer than early summer. While the amount of total nitrogen did not differ between colony and control sites, the amount of guano-based nitrogen in algae was >50% in most sites, indicating high nitrogen enrichment from colonies. Herbivores (the isopod Idotea balthica and the gastropod Theodoxus fluviatilis) preferred feeding upon the dominant macroalga Fucus vesiculosus rather than on filamentous algae or periphyton in both control and colony, and there was a significant increase in periphyton consumption near colony sites. Overall, guano from cormorant colonies seems to have effects on both producers and herbivores, as well as the potential to modify algae-herbivore interactions. PMID:23593452

  16. Marshes and turbid waters in the French Atlantic littoral

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. The multispectral information provided by ERTS-1 is very rich for the coastal regions but the cloud cover, even when only partial, often cuts up the data, and lessens its practical value. The research by densitometric methods has thus far been the most fruitful. It consists of measuring densities along preferential axes. This method has enabled the investigators to perfect a system of computer cartography for the best image. Comparative study of microdensitometric transects in four MSS bands for carefully dilimited profiles on the ground, makes it possible to isolate and recognize various types of countryside: (1) countryside of coastal plains; (2) countryside of coastal sand dunes and beaches; and (3) forms and processes of offshore domains. This study shows the usefulness of the ERTS program in establishing a rapid cartography of the physiographic units of the coastal plains in the interest of a rational program of exploitation and development.

  17. High Resolution Marine Magnetic Survey of Shallow Water Littoral Area

    PubMed Central

    Ginzburg, Boris; Cohen, Tsuriel Ram; Zafrir, Hovav; Alimi, Roger; Salomonski, Nizan; Sharvit, Jacob

    2007-01-01

    The purpose of this paper is to present a system developed for detection and accurate mapping of ferro-metallic objects buried below the seabed in shallow waters. The system comprises a precise magnetic gradiometer and navigation subsystem, both installed on a non-magnetic catamaran towed by a low-magnetic interfering boat. In addition we present the results of a marine survey of a near-shore area in the vicinity of Atlit, a town situated on the Mediterranean coast of Israel, about 15 km south of Haifa. The primary purpose of the survey was to search for a Harvard airplane that crashed into the sea in 1960. A magnetic map of the survey area (3.5 km2 on a 0.5 m grid) was created revealing the anomalies at sub-meter accuracy. For each investigated target location a corresponding ferro-metallic item was dug out, one of which turned to be very similar to a part of the crashed airplane. The accuracy of location was confirmed by matching the position of the actual dug artifacts with the magnetic map within a range of ± 1 m, in a water depth of 9 m.

  18. Ecological state of the Romanian Black Sea littoral lacustrine ecosystems

    NASA Astrophysics Data System (ADS)

    Gomoiu, M.-T.

    2009-04-01

    The author uses the results of his own researches as well as data from specialty literature to assess the ecological state of some typical lacustrine ecosystems considered, about 50 years ago, of major importance by their functions, services and researches, for the human populations in the settlements nearby. Based on this assessment the author recommends a few criteria which can be taken into account when programs of integrated management of these coastal ecosystems are initiated. The paper focuses on the study cases regarding the following major ecosystems: 1. Razelm-Sinoie Lagoon Complex - tightly linked to the Danube River and Delta systems, 2. Taşaul Lake - interfered in the last two decades by a branch of the DanubeRiver - Black Sea Canal and 3. Techirghiol Lake - for a long time under the sea level, a hyperhaline lake with therapeutic, sapropelic mud, disturbed by huge quantities of freshwaters infiltrated from the irrigation system. At present, the state of the lacustrine ecosystems at the Romanian Black Sea Coast can be characterized, mainly, by the following aspects: · Increase in the quantities of nutrients and chemical toxicants; · Rise in the level and frequency of eutrophication and pollution phenomena; · Drastic reduction of specific diversity; · Simplification of communities' structure - biocoenosis homogeneity; · Decrease in numerical abundance and biomass of benthic populations and consequently, low biofilter power by the decrease of the filter-feeder populations; · Worsening of the qualitative and the quantitative state of the biological benthic resources; · Thriving opportunistic forms (e.g. the worms causing sediment bioturbation); · Invasion by some exotic species, with harmful, unexpected consequences; · All populations undergo quantitative fluctuations; · Decrease in the fish population and in the use values of lacustrine assets, with strong impact on the welfare of the human society. Almost all pressure forms associated with the relationship between the socio-economic systems and the other components of the hierarchy of ecological systems also existed, without exception, in the Romanian coastal part of the Black Sea causing manifest ecological effects on various types of para-marine lacustrine ecosystems. Generally, we consider that the following set of effects is typical of the ecological impact resulted from the dynamics of the socio-economic systems at different time and space scales: · Erosion of diversity as a result of the loss of species or reduction in the species abundance in the local ecosystems and complex of ecosystems or because of the habitat fragmentation, isolation of valuable natural systems, to which other causes may be added such as desertification and salinization or water freshening; · Erosion of biological diversity caused by: extinction of higher species and taxa, loss of genetic resources, increase in the number of rare species threatened with extinction and significant reduction in the ethno-cultural diversity; · Depletion or reduction in the stocks of renewable and non-renewable natural resources; · Changes in the biogeochemical cycles and in the climatic system, caused by the overloading of the surface waters and soils with nutrients, heavy metals, radio-nuclides, greenhouse gases, particulate or dissolved organic matter and by deterioration of other factors. These changes cause, in their turn, a series of processes similar to chain reactions, which lead to an increasing risk of natural disasters; · Decrease in the productive and supportive capacity of components which form the foundation of the socio-economic system in the reference zone. · An alarming increase in the „environmental debt" which endangers the chances of short-term and, especially, long-term development. The author recommends some solutions in solving the conflict of interest, which consist in a set of measures and actions, as follows: · identifying synergies or contradictions between actions resulting from various policies; · improving coordination, cooperation and consultation between all concerned as the basis for sustainable development; · applying locally the principles of subsidiarity and integration, which underlie European environment and regional planning activities; · approaching the concept of "ecosystem management", that is 1. input from all levels; 2. decentralized, with feedbacks; 3. risk-taking; 4. willingness to revisit, revise and admit error; 5. shared vision; 6. across administrative boundary, and 7. partnerships). · Adopting demonstration projects to ensure good cooperation between the various planning authorities, from local to community level.

  19. The French Atlantic littoral and the Massif Armoricain, part 3

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator); Scanvic, J. Y.; Monget, J. M.

    1977-01-01

    The author has identified the following significant results: (1) An original map of lineaments of the Armorican Massif and the Vendean platform was prepared. (2) Validity of spatial information through comparison with maps of various kinds, such as geological, geophysical, morphological, etc., was verified. (3) It was confirmed that LANDSAT images, in many cases, reflect data on deep phenomena which were only accessible geophysically and by means of borings. Tectonic domains were outlined, and known lineaments were extended.

  20. Phylogeographical disjunction in abundant high-dispersal littoral gastropods.

    PubMed

    Waters, J M; King, T M; O'Loughlin, P M; Spencer, H G

    2005-08-01

    Abstract Phylogeographical disjunctions in high-dispersal marine taxa are variously ascribed to palaeogeographical conditions or contemporary ecological factors. Associated biogeographical studies, however, seldom incorporate the sampling design required to confidently discriminate among such competing hypotheses. In the current study, over 7800 gastropod specimens were examined for operculum colour, and 129 specimens genetically, to test ecological and historical biogeographical hypotheses relating to biogeographical disjunction in the Southern Hemisphere, and to southern Australia in particular. Mitochondrial DNA sequence analysis of the high-dispersal intertidal gastropod Nerita atramentosa in southern Australia (88 specimens; 18 localities) revealed an east-west phylogeographical split involving two highly divergent clades (26.0 +/- 1.9%) exhibiting minimal geographical overlap in the southeast. The eastern clade of Nerita atramentosa is also widespread in northern New Zealand (43 specimens, 10 localities), but no significant genetic differentiation is explained by the Tasman Sea, a 2000-km-wide oceanic barrier. Spatial genetic structure was not detected within either clade, consistent with the species' dispersive planktotrophic phase lasting for 5-6 months. Digital analysis of operculum colouration revealed substantial differences between eastern (tan) and western (black) specimens. Genetic analysis and visual inspection of 88 Australian specimens revealed a completely nonrandom association between mtDNA data and operculum colouration. Independent examination of a further 7822 specimens from 14 sites in southern Australia revealed both colour morphs at all localities, but reinforced the phylogeographical data by indicating a marked turnover in colour morph abundance associated with a palaeogeographical barrier: Wilsons Promontory. This sharp biogeographical disjunction is in marked contrast to the species' high dispersal abilities. The genetic similarity of Nerita morio (Easter Island) and the eastern Australian + New Zealand lineage (1.1 +/- 0.3%) provides further evidence of long-distance dispersal in southern Nerita. Phylogenetic relationships of nine species (four genera) of Neritidae, an almost exclusively tropical gastropod family, are consistent with the hypothesis that southern temperate black nerites comprise a monophyletic radiation. PMID:16029478

  1. The French Atlantic Littoral and the Massif Armoricain

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator); Monget, J. M.; Scanvic, J. Y.

    1976-01-01

    The author has identified the following significant results. Diachronic use of LANDSAT data time series will in time allow statistical study of submersion frequencies in tidal areas. This is an essential element of coastal geomorphology and of coastal zone management being particularly useful in siting shellfish farms. Maps are being obtained at useable scales and simple, user oriented legends which can be used for coastal planning.

  2. Removal of cholesteryl ester from hepatic reticuloendothelial cells in vivo is not enhanced by plasma cholesteryl ester transfer protein.

    PubMed

    Stein, O; Dabach, Y; Hollander, G; Stein, Y

    1991-01-28

    The putative role of cholesteryl ester transfer protein (CETP) in the removal of cholesteryl ester from hepatic reticuloendothelial cells in vivo was studied in hamsters. The parameter tested was retention of [3H]cholesteryl linoleyl ether ([3H]CLE), a nonhydrolysable analog of cholesteryl ester, in the liver after injection of [3H]CLE labeled acetylated LDL, which is targetted to nonparenchymatous littoral cells. In hamsters fed laboratory chow, plasma cholesteryl ester transfer activity (CETA) was 10.6 +/- 0.9 units and the retention of [3H]CLE in the liver 28 days after injection was 86% of the 4 h value. It was about 55% in rats fed the same diet, in which CETA was not detectable. When the diet was supplemented with 2% cholesterol and 15% margarine, CETA activity in hamsters increased 2-fold, yet no change in retention of [3H]CLE in liver was seen after 28 days. In rats, the retention of [3H]CLE in the liver was also not changed by the dietary fat supplementation. These results do not support the role of CETP in vivo in removal of cholesteryl ester from intact reticuloendothelial cells. PMID:1998742

  3. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  4. Cell Structure

    MedlinePlus

    ... Cells, Tissues, & Membranes Cell Structure & Function Cell Structure Cell Function Body Tissues Epithelial Tissue Connective Tissue Muscle Tissue ... apparatus , and lysosomes . « Previous (Cell Structure & Function) Next (Cell Function) » Contact Us | Privacy Policy | Accessibility | FOIA | File Formats ...

  5. Stem Cells

    MedlinePlus

    Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  6. T Cells

    MedlinePlus

    ... or turn off the immune response. Cytotoxic or “killer” T cells directly attack and destroy cells bearing ... involve selective activation of helper T cells and killer T cells, with a corresponding decrease in regulatory ...

  7. Cell division

    MedlinePlus Videos and Cool Tools

    ... hours after conception, the fertilized egg cell remains a single cell. After approximately 30 hours, it divides ... 3 days, the fertilized egg cell has become a berry-like structure made up of 16 cells. ...

  8. Cell counting.

    PubMed

    Phelan, M C; Lawler, G

    2001-05-01

    This unit presents protocols for counting cells using either a hemacytometer or electronically using a Coulter counter. Cell counting with a hemacytometer permits effective discrimination of live from dead cells using trypan blue exclusion. In addition, the procedure is less subject to errors arising from cell clumping or size heterogeneity. Counting cells is more quickly and easily performed using an electronic counter, but live-dead discrimination is unreliable. Cell populations containing large numbers of dead cells and/or cell clumps are difficult to count accurately. In addition, electronic counting requires resetting of the instrument for cell populations of different sizes; heterogeneous populations can give rise to inaccurate counts, and resting and activated cells may require counting at separate settings. In general, electronic cell counting is best performed on fresh peripheral blood cells. PMID:18770655

  9. Galvanic Cells

    ERIC Educational Resources Information Center

    Young, I. G.

    1973-01-01

    Many standard physical chemistry textbooks contain ambiguities which lead to confusion about standard electrode potentials, calculating cell voltages, and writing reactions for galvanic cells. This article shows how standard electrode potentials can be used to calculate cell voltages and deduce cell reactions. (Author/RH)

  10. Cell Biochips

    NASA Astrophysics Data System (ADS)

    Pioufle, B. Le; Picollet-D'Hahan, N.

    A cell biochip is a microsystem, equipped with electronic and microfluidic functions, designed to manipulate or analyse living cells. The first publications in this emerging area of research appeared toward the end of the 1980s. In 1989 Washizu described a biochip designed to fuse two cells by electropermeabilisation of the cytoplasmic membrane [1]. Research centers have devised a whole range of cell chip structures, for simultaneous or sequential analysis of single cells, cell groups, or cell tissues reconstituted on the chip. The cells are arranged in a square array on a parallel cell chip for parallel analysis, while they are examined and processed one by one in a microchannel in the case of a series cell chip. In contrast to these biochips for high-throughput analysis of a large number of cells, single-cell chips focus on the analysis of a single isolated cell. As in DNA microarrays, where a large number of oligonucleotides are ordered in a matrix array, parallel cell chips order living cells in a similar way. At each point of the array, the cells can be isolated, provided that the cell type allows this, e.g., blood cells, or cultivated in groups (most adhesion cells can only survive in groups). The aim is to allow massively parallel analysis or processing. Le Pioufle et al. describe a microdevice for the culture of single cells or small groups of cells in a micropit array [2]. Each pit is equipped to stimulate the cell or group of cells either electrically or fluidically. Among the applications envisaged are gene transfer, cell sorting, and screening in pharmacology. A complementary approach, combining the DNA microarray and cell biochip ideas, has been put forward by Bailey et al. [3]. Genes previously arrayed on the chip transfect the cultured cells on the substrate depending on their position in the array (see Fig. 19.1). This way of achieving differential lipofection on a chip was then taken up again by Yoshikawa et al. [4] with primary cells, more

  11. Cell division

    MedlinePlus Videos and Cool Tools

    ... structure made up of 16 cells. This structure is called a morula, which is Latin for mulberry. The cells continue to divide ... days following conception into a blastocyst. Although it is only the size of a pinhead, the blastocyst ...

  12. Solar cells

    NASA Astrophysics Data System (ADS)

    Cuquel, A.; Roussel, M.

    The physical and electronic characteristics of solar cells are discussed in terms of space applications. The principles underlying the photovoltaic effect are reviewed, including an analytic model for predicting the performance of individual cells and arrays of cells. Attention is given to the effects of electromagnetic and ionizing radiation, micrometeors, thermal and mechanical stresses, pollution and degassing encountered in space. The responses of different types of solar cells to the various performance-degrading agents are examined, with emphasis on techniques for quality assurance in the manufacture and mounting of Si cells.

  13. Types of Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  14. Electrolytic cell

    NASA Astrophysics Data System (ADS)

    Bullock, J. S.; Hale, B. D.

    1984-09-01

    An apparatus is described for the separation of the anolyte and the catholyte during electrolysis. The electrolyte flows through an electrolytic cell between the oppositely charged electrodes. The cell is equipped with a wedge-shaped device, the tapered end is located between the electrodes on the effluent side of the cell. The wedge diverts the flow of the electrolyte to either side of the wedge, substantially separating the anolyte and the catholyte.

  15. Cell Chauvinism

    ERIC Educational Resources Information Center

    Keller, Dolores Elaine

    1972-01-01

    Indicates that biological terminology, such as mother cell'' and labels of sex factors in bacteria, reflect discrimination against females by reinforcing perpetuation of stereotyped gender roles. (AL)

  16. Cell migration.

    PubMed

    Trepat, Xavier; Chen, Zaozao; Jacobson, Ken

    2012-10-01

    Cell migration is fundamental to establishing and maintaining the proper organization of multicellular organisms. Morphogenesis can be viewed as a consequence, in part, of cell locomotion, from large-scale migrations of epithelial sheets during gastrulation, to the movement of individual cells during development of the nervous system. In an adult organism, cell migration is essential for proper immune response, wound repair, and tissue homeostasis, while aberrant cell migration is found in various pathologies. Indeed, as our knowledge of migration increases, we can look forward to, for example, abating the spread of highly malignant cancer cells, retarding the invasion of white cells in the inflammatory process, or enhancing the healing of wounds. This article is organized in two main sections. The first section is devoted to the single-cell migrating in isolation such as occurs when leukocytes migrate during the immune response or when fibroblasts squeeze through connective tissue. The second section is devoted to cells collectively migrating as part of multicellular clusters or sheets. This second type of migration is prevalent in development, wound healing, and in some forms of cancer metastasis. PMID:23720251

  17. Cell Migration

    PubMed Central

    Trepat, Xavier; Chen, Zaozao; Jacobson, Ken

    2015-01-01

    Cell migration is fundamental to establishing and maintaining the proper organization of multicellular organisms. Morphogenesis can be viewed as a consequence, in part, of cell locomotion, from large-scale migrations of epithelial sheets during gastrulation, to the movement of individual cells during development of the nervous system. In an adult organism, cell migration is essential for proper immune response, wound repair, and tissue homeostasis, while aberrant cell migration is found in various pathologies. Indeed, as our knowledge of migration increases, we can look forward to, for example, abating the spread of highly malignant cancer cells, retarding the invasion of white cells in the inflammatory process, or enhancing the healing of wounds. This article is organized in two main sections. The first section is devoted to the single-cell migrating in isolation such as occurs when leukocytes migrate during the immune response or when fibroblasts squeeze through connective tissue. The second section is devoted to cells collectively migrating as part of multicellular clusters or sheets. This second type of migration is prevalent in development, wound healing, and in some forms of cancer metastasis. PMID:23720251

  18. Cell Trivision of Hyperploid Cells

    PubMed Central

    Nagy, Gabor; Kiraly, Gabor; Turani, Melinda

    2013-01-01

    Malignant transformation is likely to render cells hyperploid, primarily tetraploid. We have measured the frequency of division into three rather than two daughter cells as a function of ploidy. Such trivisions were followed in near-tetraploid uveal melanoma (UM), hypotetraploid HaCaT (<4 N), hypertriploid HeLa (>3 N), and in near-diploid (∼2 N) lung epithelial cell lines by time-lapse image analyses. A stepwise analysis of cytokinesis revealed higher frequency of cell trivisions relative to divisions in hyperploid HeLa (1:24, 4%), HaCaT (1:126, 8%), and UM (1:186, 0.5%) cells. The occurrence of trivision was significantly lower in near-diploid endothelial cells (1:1400, 0.07%). We have previously observed the phenomenon of trivision in HaCaT cells treated with heavy metal lead, and here we describe that trivision is a spontaneous process taking place without genotoxic treatment. Beside re-diploidization by trivision, the hyperploid state decreases the cell size of the daughter cells and is likely to increase the time of cytokinesis. On the basis of the results, it is hypothesized that among other cancer-related causes, hyperploidy could be related to cell trivision, could cause random aneuploidy, and could generate new cancer-specific karyotypes. PMID:24093497

  19. Photovoltaic cell

    SciTech Connect

    Bronstein-Bonte, I.Y.; Fischer, A.B.

    1986-12-16

    This patent describes a product comprising a photovoltaic cell including a luminescent dye which will absorb radiation at a wavelength to which the cell is not significantly responsive and emit radiation at a higher wavelength at which it is responsive. The improvement described here is wherein the dye comprises a lepidopterene.

  20. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  1. Cell Lines

    PubMed Central

    Cherbas, Lucy; Gong, Lei

    2014-01-01

    We review the properties and uses of cell lines in Drosophila research, emphasizing the variety of lines, the large body of genomic and transcriptional data available for many of the lines, and the variety of ways the lines have been used to provide tools for and insights into the developmental, molecular, and cell biology of Drosophila and mammals. PMID:24434506

  2. Host cells and cell banking.

    PubMed

    Stacey, Glyn N; Merten, Otto-Wilhelm

    2011-01-01

    Gene therapy based on the use of viral vectors is entirely dependent on the use of animal cell lines, mainly of mammalian origin, but also of insect origin. As for any biotechnology product for clinical use, viral -vectors have to be produced with cells derived from an extensively characterized cell bank to maintain the appropriate standard for assuring the lowest risk for the patients to be treated. Although many different cell types and lines have been used for the production of viral vectors, HEK293 cells or their derivatives have been extensively used for production of different vector types: adenovirus, oncorectrovirus, lentivirus, and AAV vectors, because of their easy handling and the possibility to grow them adherently in serum-containing medium as well as in suspension in serum-free culture medium. Despite this, these cells are not necessarily the best for the production of a given viral vector, and there are many other cell lines with significant advantages including superior growth and/or production characteristics, which have been tested and also used for the production of clinical vector batches. This chapter presents basic -considerations concerning the characterization of cell banks, in the first part, and, in the second part, practically all cell lines (at least when public information was available) established and developed for the production of the most important viral vectors (adenoviral, oncoretroviral, lentiviral, AAV, baculovirus). PMID:21590393

  3. Fuel cells 101

    SciTech Connect

    Hirschenhofer, J.H.

    1999-07-01

    This paper discusses the various types of fuel cells, the importance of cell voltage, fuel processing for natural gas, cell stacking, fuel cell plant description, advantages and disadvantages of the types of fuel cells, and applications. The types covered include: polymer electrolyte fuel cell, alkaline fuel cell, phosphoric acid fuel cell; molten carbonate fuel cell, and solid oxide fuel cell.

  4. Cell polarity

    PubMed Central

    Romereim, Sarah M

    2011-01-01

    Despite extensive genetic analysis of the dynamic multi-phase process that transforms a small population of lateral plate mesoderm into the mature limb skeleton, the mechanisms by which signaling pathways regulate cellular behaviors to generate morphogenetic forces are not known. Recently, a series of papers have offered the intriguing possibility that regulated cell polarity fine-tunes the morphogenetic process via orienting cell axes, division planes and cell movements. Wnt5a-mediated non-canonical signaling, which may include planar cell polarity, has emerged as a common thread in the otherwise distinct signaling networks that regulate morphogenesis in each phase of limb development. These findings position the limb as a key model to elucidate how global tissue patterning pathways direct local differences in cell behavior that, in turn, generate growth and form. PMID:22064549

  5. 9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. ENGINE TEST CELL BUILDING INTERIOR. CELL ACCESS ELEVATOR, CELLS 2 AND 4, BASEMENT LEVEL. LOOKING SOUTHEAST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA

  6. Squamous cell skin cancer

    MedlinePlus

    ... cell; NMSC - squamous cell; Squamous cell skin cancer; Squamous cell carcinoma of the skin ... squamous cell cancer is called Bowen disease (or squamous cell carcinoma in situ). This type does not spread to ...

  7. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1996-07-16

    An electrochemical cell is described having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm{sup 3}; the cell can be 90% recharged in three hours and can operate at temperatures below 160 C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6{times}10{sup 4}cm{sup 2}/g of Ni. 6 figs.

  8. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1994-01-01

    An electrochemical cell having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm.sup.3 ; the cell can be 90% recharged in three hours and can operate at temperatures below 160.degree. C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6.times.10.sup.4 cm.sup.2 /g of Ni.

  9. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1996-01-01

    An electrochemical cell having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm.sup.3 ; the cell can be 90% recharged in three hours and can operate at temperatures below 160.degree. C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6.times.10.sup.4 cm.sup.2 /g of Ni.

  10. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1994-02-01

    An electrochemical cell is described having a bimodal positive electrode, a negative electrode of an alkali metal, and a compatible electrolyte including an alkali metal salt molten at the cell operating temperature. The positive electrode has an electrochemically active layer of at least one transition metal chloride at least partially present as a charging product, and additives of bromide and/or iodide and sulfur in the positive electrode or the electrolyte. Electrode volumetric capacity is in excess of 400 Ah/cm[sup 3]; the cell can be 90% recharged in three hours and can operate at temperatures below 160 C. There is also disclosed a method of reducing the operating temperature and improving the overall volumetric capacity of an electrochemical cell and for producing a positive electrode having a BET area greater than 6[times]10[sup 4] cm[sup 2]/g of Ni. 8 figures.

  11. Dry cell battery poisoning

    MedlinePlus

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  12. Load cell

    DOEpatents

    Spletzer, Barry L.

    2001-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs which can be combined to determine any one of the six general load components.

  13. Load cell

    DOEpatents

    Spletzer, B.L.

    1998-12-15

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components. 16 figs.

  14. Load cell

    DOEpatents

    Spletzer, Barry L.

    1998-01-01

    A load cell combines the outputs of a plurality of strain gauges to measure components of an applied load. Combination of strain gauge outputs allows measurement of any of six load components without requiring complex machining or mechanical linkages to isolate load components. An example six axis load cell produces six independent analog outputs, each directly proportional to one of the six general load components.

  15. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1994-01-01

    An electrochemical cell having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a .beta." alumina electrolyte and NaAlCl.sub.4 or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose.

  16. Cell sealant

    SciTech Connect

    Markin, C.; Book, R.J.; James, D.A.

    1988-04-26

    An electrochemical cell is described comprising an anode, a cathode and an electrolyte disposed within an open ended cylindrical metallic cell container, with an insulative cell top member being positioned within the open end of a sealant at the interface between the cell top member and the metallic cell container. The sealant is a mixture of a Type 2 BUR asphalt and an elastomeric material selected from the group consisting of (cis-1,4-polyisoprene), styrene-butadiene copolymer (SBR), cis-1,4-polybutadiene and styrene butadiene styrene (SBS), styrene isoprene styrene (SIS), neoprene (poly-chloprene), acrylonitrile-butadiene copolymer (NBR), ethylene-propylene elastomers (EPR), butyl rubber (copolymers of isobutylene), urethane, nitrile (polymers of butadiene and acrylonitrile), polysulfide, polyacrylate, silicone, chlorosulfonated polyethylene, and EPDM (terpolymers of ethylene, propylene and diene monomers), and mixtures thereof, and wherein the elastomeric material is substantially inert to the electrolyte and is present in an amount between 0.5% to 10% by weight of the asphalt.

  17. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Myles, Kevin M.; Vissers, Donald R.; Prakash, Jai

    1996-01-01

    An electrochemical cell with a positive electrode having an electrochemically active layer of at least one transition metal chloride. A negative electrode of an alkali metal and a compatible electrolyte including an alkali metal salt molten at cell operating temperature is included in the cell. The electrolyte is present at least partially as a corrugated .beta." alumina tube surrounding the negative electrode interior to the positive electrode. The ratio of the volume of liquid electrolyte to the volume of the positive electrode is in the range of from about 0.1 to about 3. A plurality of stacked electrochemical cells is disclosed each having a positive electrode, a negative electrode of an alkali metal molten at cell operating temperature, and a compatible electrolyte. The electrolyte is at least partially present as a corrugated .beta." alumina sheet separating the negative electrode and interior to the positive electrodes. The alkali metal is retained in a porous electrically conductive ceramic, and seals for sealing the junctures of the electrolyte and the adjacent electrodes at the peripheries thereof.

  18. Electrochemical cell

    DOEpatents

    Redey, L.I.; Myles, K.M.; Vissers, D.R.; Prakash, J.

    1996-07-02

    An electrochemical cell is described with a positive electrode having an electrochemically active layer of at least one transition metal chloride. A negative electrode of an alkali metal and a compatible electrolyte including an alkali metal salt molten at cell operating temperature is included in the cell. The electrolyte is present at least partially as a corrugated {beta}{double_prime} alumina tube surrounding the negative electrode interior to the positive electrode. The ratio of the volume of liquid electrolyte to the volume of the positive electrode is in the range of from about 0.1 to about 3. A plurality of stacked electrochemical cells is disclosed each having a positive electrode, a negative electrode of an alkali metal molten at cell operating temperature, and a compatible electrolyte. The electrolyte is at least partially present as a corrugated {beta}{double_prime} alumina sheet separating the negative electrode and interior to the positive electrodes. The alkali metal is retained in a porous electrically conductive ceramic, and seals for sealing the junctures of the electrolyte and the adjacent electrodes at the peripheries thereof. 8 figs.

  19. Electrochemical cell

    DOEpatents

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  20. Electrochemical cell

    DOEpatents

    Nagy, Z.; Yonco, R.M.; You, H.; Melendres, C.A.

    1992-08-25

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90[degree] in either direction while maintaining the working and counter electrodes submerged in the electrolyte. 5 figs.

  1. Cell Phones

    PubMed Central

    Sansone, Lori A.

    2013-01-01

    Cell phones are a relatively novel and evolving technology. While the potential benefits of this technology continue to emerge, so do the potential psychosocial risks. For example, one psychosocial risk is user stress, which appears to be related to feeling compelled to promptly respond to cell-phone activity in order to maintain spontaneity and access with others. Other potential psychosocial risks include disruptions in sleep; the user’s risk of exposure to cyberbullying, particularly the unwanted exposure of photographs and/or videos of the victim; and overuse, particularly among adolescents. With regard to the latter phenomenon, the boundaries among overuse, misuse, dependence, and addiction are not scientifically clear. Therefore, while cell phones are a convenient and expedient technology, they are not without their potential psychosocial hazards. PMID:23439568

  2. Solar cells

    NASA Astrophysics Data System (ADS)

    Treble, F. C.

    1980-11-01

    The history, state of the art, and future prospects of solar cells are reviewed. Solar cells are already competitive in a wide range of low-power applications, and during the 1980's they are expected to become cheaper to run than diesel or gasoline generators, the present mainstay of isolated communities. At this stage they will become attractive for water pumping, irrigation, and rural electrification, particularly in developing countries. With further cost reduction, they may be used to augment grid supplies in domestic, commercial, institutional, and industrial premises. Cost reduction to the stage where photovoltaics becomes economic for large-scale power generation in central stations depends on a technological breakthrough in the development of thin-film cells. DOE aims to reach this goal by 1990, so that by the end of the century about 20% of the estimated annual additions to their electrical generating capacity will be photovoltaic.

  3. Electrochemical cell

    DOEpatents

    Kaun, T.D.

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5 to 1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1 to 10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  4. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1994-08-23

    An electrochemical cell is described having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a [beta] alumina electrolyte and NaAlCl[sub 4] or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose. 6 figs.

  5. Cell Libraries

    NASA Technical Reports Server (NTRS)

    1994-01-01

    A NASA contract led to the development of faster and more energy efficient semiconductor materials for digital integrated circuits. Gallium arsenide (GaAs) conducts electrons 4-6 times faster than silicon and uses less power at frequencies above 100-150 megahertz. However, the material is expensive, brittle, fragile and has lacked computer automated engineering tools to solve this problem. Systems & Processes Engineering Corporation (SPEC) developed a series of GaAs cell libraries for cell layout, design rule checking, logic synthesis, placement and routing, simulation and chip assembly. The system is marketed by Compare Design Automation.

  6. Electrochemical cell

    DOEpatents

    Kaun, Thomas D.

    1984-01-01

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5-1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1-10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  7. Stem Cell Basics

    MedlinePlus

    ... stem cells? What are the potential uses of human stem cells and the obstacles that must be overcome before ... two kinds of stem cells from animals and humans: embryonic stem cells and non-embryonic "somatic" or "adult" stem cells . ...

  8. Stem Cell Information: Glossary

    MedlinePlus

    ... based therapies Cell culture Cell division Chromosome Clone Cloning Cord blood stem cells Culture medium Differentiation Directed ... Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) ...

  9. Learn About Stem Cells

    MedlinePlus

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  10. Photoelectrodialytic cell

    DOEpatents

    Murphy, G.W.

    1983-09-13

    A multicompartment photoelectrodialytic demineralization cell is provided with a buffer compartment interposed between the product compartment and a compartment containing an electrolyte solution. Semipermeable membranes separate the buffer compartment from the product and electrolyte compartments. The buffer compartment is flushed to prevent leakage of the electrolyte compartment from entering the product compartment. 3 figs.

  11. Photovoltaic cell

    DOEpatents

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  12. Nonaqueous cell

    SciTech Connect

    Kalnoki-kis, T.

    1981-07-07

    A nonaqueous cell is disclosed that utlizes an active metal anode, such as lithium, a cathode collector and an ionically conductive cathode electrolyte comprising a solute dissolved in a liquid cathode, such as an oxyhalide, and wherein a vinyl polymer is dissolved in the cathode-electrolyte.

  13. Potent Cells

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  14. 19. Oblique, typical cell (south cells) from rear of cell; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Oblique, typical cell (south cells) from rear of cell; view to north, 65mm lens with electronic flash illumination. - Tule Lake Project Jail, Post Mile 44.85, State Route 139, Newell, Modoc County, CA

  15. Fiber-optic hydrophone array for acoustic surveillance in the littoral

    NASA Astrophysics Data System (ADS)

    Hill, David; Nash, Phillip

    2005-05-01

    We describe a fibre-optic hydrophone array system architecture that can be tailored to meet the underwater acoustic surveillance requirements of the military, counter terrorist and customs authorities in protecting ports and harbours, offshore production facilities or coastal approaches. Physically the fibre-optic hydrophone array is in the form of a lightweight cable, enabling rapid deployment from a small vessel. Based upon an optical architecture of time and wavelength multiplexed interferometric hydrophones, the array is comprised of a series of hydrophone sub-arrays. Using multiple sub-arrays, extended perimeters many tens of kilometres in length can be monitored. Interrogated via a long (~50km) optical fibre data link, the acoustic date is processed using the latest open architecture sonar processing platform, ensuring that acoustic targets below, on and above the surface are detected, tracked and classified. Results obtained from an at sea trial of a 96-channel hydrophone array are given, showing the passive detection and tracking of a diver, small surface craft and big ocean going ships beyond the horizon. Furthermore, we describe how the OptaMarine fibre-optic hydrophone array fits into an integrated multi-layered approach to port and harbour security consisting of active sonar for diver detection and hull imaging, as well as thermal imaging and CCTV for surface monitoring. Finally, we briefly describe a complimentary land perimeter intruder detection system consisting of an array of fibre optic accelerometers.

  16. Temporal asymmetries in the feeding patterns along the tidal cycle in two sympatric littoral blennies

    NASA Astrophysics Data System (ADS)

    Faria, C.; Almada, V. C.

    2008-09-01

    The temporal patterns of feeding activity of Lipophrys pholis and Coryphoblennius galerita were studied by snorkelling dives during high-waters. The feeding activity was especially intense during the rising-tide when compared to the ebbing-tide. The relative abundances of C. galerita and small L. pholis observed on rock-walls were higher during the rising- and high-tide. However, L. pholis larger than 7-8 cm showed higher relative abundance on rock-walls during the ebbing phase, apparently because they move up and down with the tide, and many individuals were in their downward movements as the tide ebbs. It is hypothesized that the asymmetry in feeding pattern observed in both species reflects a trade off between two conflicting needs, maximizing feeding time and reaching their low-tide shelters in time, avoiding the risk of getting stranded in unsuitable locations.

  17. Evidence for long-term uplift on the Canary Islands from emergent Mio Pliocene littoral deposits

    NASA Astrophysics Data System (ADS)

    Meco, Joaquín; Scaillet, Stéphane; Guillou, Hervé; Lomoschitz, Alejandro; Carlos Carracedo, Juan; Ballester, Javier; Betancort, Juan-Francisco; Cilleros, Antonio

    2007-06-01

    Several islands in the Canarian archipelago show marine deposits with identical fossil faunas, which are generally assigned to different glacioeustatic marine episodes: mainly Pleistocene episodes in Lanzarote and Fuerteventura, and Mio-Pliocene ones in Gran Canaria. Three fossil species ( Saccostrea chili, Nerita emiliana and Strombus coronatus) characterize all the marine deposits from southern Lanzarote, to the west and south of Fuerteventura and northeast of Gran Canaria. Three other species ( Ancilla glandiformis, Rothpletzia rudista and Siderastraea miocenica) confirm the chronostratigraphic attribution of these deposits. Other more occasional fossils (as Chlamys latissima, Isognomon soldanii and Clypeaster aegyptiacus) fit an upper Miocene and lower Pliocene age. This agrees with new K/Ar ages obtained from pillow lavas emplaced into the marine deposits (ca. 4.1 Ma in Gran Canaria, ca. 4.8 Ma in Fuerteventura) and from underlying (ca. 9.3 Ma in Gran Canaria) or overlying (ca. 9.8 Ma in Lanzarote) lava flows. The marine deposits are eroded but large continuous segments are preserved sloping gently towards the coast. Variations in the highest and the lowest elevations of the deposits apsl (above present sea level) indicate post-depositional uplift movements. Glacioeustatic causes are unlikely to be responsible for these variations on the basis of the coastal location of the deposits and their equatorial fauna characteristic of Mio-Pliocene corals. Differential uplift of the deposits across the archipelago is argued to result from the progressive seaward tilting of the islands along the insular volcanic trail marking the westward migration of hot spot head since 20 Ma. Successive westward accretion of younger volcanic edifices resulted in increasing lithostatic load of the crust with progressive (diachronous) tilting of the older edifices and their palaeo-shorelines marked by past coastal deposits.

  18. Functional Changes in Littoral Macroinvertebrate Communities in Response to Watershed-Level Anthropogenic Stress

    PubMed Central

    Kovalenko, Katya E.; Brady, Valerie J.; Ciborowski, Jan J. H.; Ilyushkin, Sergey; Johnson, Lucinda B.

    2014-01-01

    Watershed-scale anthropogenic stressors have profound effects on aquatic communities. Although several functional traits of stream macroinvertebrates change predictably in response to land development and urbanization, little is known about macroinvertebrate functional responses in lakes. We assessed functional community structure, functional diversity (Rao’s quadratic entropy) and voltinism in macroinvertebrate communities sampled across the full gradient of anthropogenic stress in Laurentian Great Lakes coastal wetlands. Functional diversity and voltinism significantly decreased with increasing development, whereas agriculture had smaller or non-significant effects. Functional community structure was affected by watershed-scale development, as demonstrated by an ordination analysis followed by regression. Because functional community structure affects energy flow and ecosystem function, and functional diversity is known to have important implications for ecosystem resilience to further environmental change, these results highlight the necessity of finding ways to remediate or at least ameliorate these effects. PMID:25006811

  19. Analysis of the recent storm record in the southwestern Spanish coast: implications for littoral management.

    PubMed

    Rodríguez-Ramírez, A; Ruiz, F; Cáceres, L M; Rodríguez Vidal, J; Pino, R; Muñoz, J M

    2003-03-01

    This work compares the geomorphologic evolution of the Huelva coast (SW Spain), some climatic-oceanographic data of the Cádiz Gulf and the recent storm record of this zone, covering the last 4 decades (1956-1996). An interesting correlation was found between the southwestern wind periodicity, the number of storm periods and the beach ridges observed in the main spits (El Rompido and Doñana). The spectral analysis of the wind time series permits to establish two most probable levels of periodicity: 6 and 9-10 years. Both periods coincide with the storm record and the creation of new beach ridges after a high-energy period. Beach damage, another storm-induced effect, was analysed by deducing different implications for the future management of tourist localities. PMID:12606159

  20. Biological structure and dynamics of littoral fish assemblages in the eastern Finger Lakes

    USGS Publications Warehouse

    McKenna, James E., Jr.

    2001-01-01

    Fish assemblages from three of the New York Finger Lakes were examined for structure within and between lakes and over time. Species-area relationships indicated that local fish assemblages are the result of recent, lake-specific events that altered the regional species pool. Fish assemblages varied among seasons and those occupying eutrophic waters had different characteristics from those in oligotrophic waters. Bluntnose minnows (Pimephales notatus) were a persistent and important component of most assemblages, but abundance of bluegill (Lepomis macrochirus) was the most distinguishing feature. Species associations indicated that interactions among the fishes had little influence on assemblage structure. Correlations between community structure and abiotic factors were identified. Ten abiotic variables were strongly associated with the species assemblages, but could not fully explain differences between assemblages. Results indicate that the abundance and diversity of water column feeders was related to productivity of lake habitat. In general, fish populations were smaller in oligotrophic waters and water column feeders were poorly represented in those assemblages. Productivity at various trophic levels was implicated as a major factor determining lake fish assemblage structure.

  1. Vitamin D Status among Older Adults Residing in the Littoral and Andes Mountains in Ecuador

    PubMed Central

    Orces, Carlos H.

    2015-01-01

    Objectives. To estimate the prevalence of 25-hydroxyvitamin D (25(OH)D) deficiency and its determinants among older adults in Ecuador. Methods. 25(OH)D deficiency and insufficiency prevalence rates were examined among participants in the National Survey of Health, Wellbeing, and Aging. Logistic regression models were used to evaluate demographic characteristics associated with 25(OH)D deficiency. Results. Of 2,374 participants with a mean age of 71.0 (8.3) years, 25(OH)D insufficiency and deficiency were present in 67.8% (95% CI, 65.3–70.2) and 21.6% (95% CI, 19.5–23.7) of older adults in Ecuador, respectively. Women (OR, 3.19; 95% CI, 3.15–3.22), self-reported race as Indigenous (OR, 2.75; 95% CI, 2.70–2.80), and residents in rural (OR, 4.49; 95% CI, 4.40–4.58) and urban (OR, 2.74; 95% CI, 2.69–2.80) areas of the Andes Mountains region were variables significantly associated with 25(OH)D deficiency among older adults. Conclusions. Despite abundant sunlight throughout the year in Ecuador, 25(OH)D deficiency was significantly prevalent among older women, Indigenous subjects, and subjects residing in the Andes Mountains region of the country. The present findings may assist public health authorities to implement policies of vitamin D supplementation among older adults at risk for this condition. PMID:26301259

  2. WaveQ3D: Fast and accurate acoustic transmission loss (TL) eigenrays, in littoral environments

    NASA Astrophysics Data System (ADS)

    Reilly, Sean M.

    This study defines a new 3D Gaussian ray bundling acoustic transmission loss model in geodetic coordinates: latitude, longitude, and altitude. This approach is designed to lower the computation burden of computing accurate environmental effects in sonar training application by eliminating the need to transform the ocean environment into a collection of Nx2D Cartesian radials. This approach also improves model accuracy by incorporating real world 3D effects, like horizontal refraction, into the model. This study starts with derivations for a 3D variant of Gaussian ray bundles in this coordinate system. To verify the accuracy of this approach, acoustic propagation predictions of transmission loss, time of arrival, and propagation direction are compared to analytic solutions and other models. To validate the model's ability to predict real world phenomena, predictions of transmission loss and propagation direction are compared to at-sea measurements, in an environment where strong horizontal refraction effect have been observed. This model has been integrated into U.S. Navy active sonar training system applications, where testing has demonstrated its ability to improve transmission loss calculation speed without sacrificing accuracy.

  3. Mussels as ecosystem engineers: Their contribution to species richness in a rocky littoral community

    NASA Astrophysics Data System (ADS)

    Borthagaray, Ana Inés; Carranza, Alvar

    Mussels are important ecosystem engineers in marine benthic systems because they aggregate into beds, thus modifying the nature and complexity of the substrate. In this study, we evaluated the contribution of mussels ( Brachidontes rodriguezii, Mytilus edulis platensis, and Perna perna) to the benthic species richness of intertidal and shallow subtidal communities at Cerro Verde (Uruguay). We compared the richness of macro-benthic species between mussel-engineered patches and patches without mussels but dominated by algae or barnacles at a landscape scale (all samples), between tidal levels, and between sites distributed along a wave exposition gradient. Overall, we found a net increase in species richness in samples with mussels (35 species), in contrast to samples where mussels were naturally absent or scarce (27 species). The positive trend of the effect did not depend upon tidal level or wave exposition, but its magnitude varied between sites. Within sites, a significant positive effect was detected only at the protected site. Within the mussel-engineered patches, the richness of all macro-faunal groups (total, sessile and mobile) was positively correlated with mussel abundance. This evidence indicates that the mussel beds studied here were important in maintaining species richness at the landscape-level, and highlights that beds of shelled bivalves should not be neglected as conservation targets in marine benthic environments.

  4. The French Atlantic Littoral and the Massif Armoricain. [Bay of Biscay, France and Spain

    NASA Technical Reports Server (NTRS)

    Verger, F. (Principal Investigator); Monget, J. M.; Scanvic, J. Y.

    1976-01-01

    The author has identified the following significant results. Diachronic use of LANDSAT data time series will in time allow study of statistically submerged frequencies in tidal areas. This is an essential element of coastal geomorphology and of coastal zone management, being particularly useful in siting shellfish farms. Maps at useable scales and simple user oriented legends should become an essential document for coastal planning agencies.

  5. ECOLOGICAL ASSESSMENT OF GENERALIZED LITTORAL ENVIRONMENTS DECISION-SUPPORT SYSTEM (EAGLE/OS)

    EPA Science Inventory

    The outcomes include an assessment of probabilities of high water quality conditions or risks of extreme water quality degradation due to synergistic forcing functions, a decision-support system that integrates available real-time or near-real-time environmental and satelli...

  6. Synoptic patterns of meiofaunal and macrofaunal abundances and specific composition in littoral sediments

    NASA Astrophysics Data System (ADS)

    Armonies, Werner; Hellwig-Armonies, Monika

    1987-03-01

    During recent years, many investigations on small zoobenthos have been performed at the island of Sylt. As these studies were carried out sporadically over many years and as different extraction methods were used, comparisons of the results have been hampered. Therefore, in August/September 1986, 24 sites were sampled and evaluated using one quantitative method throughout. Sites range from mud to exposed sand and from the sublittoral to the supralittoral. Macrofauna and the taxa Plathelminthes, Polychaeta, and Oligochaeta are determined to species level. Macrofaunal (>0.5 mm) abundance is highest in mud and continuously decreases with increasing exposure to wave action. Meiofaunal (<0.5 mm) abundance is less variable. Nematoda dominate in mud and muddy sand, Copepoda in sheltered and exposed sand, other taxa only intermittently. Related to surface area, no correlation between macro-and meiofaunal abundance is apparent. Plathelminthes and Copepoda reach highest abundance per surface area in sand but their per volume density is higher in mud and muddy sand. Related to sediment volume instead of surface area, the meiofaunal abundance pattern is very similar to the macrofaunal pattern. The faunal composition changes gradually along the tidal gradient without general faunal boundaries. On an averange, the faunal similarity of neighbouring sites is highest in Oligochaeta and lowest in Plathelminthes. Presumably, Oligochaeta tolerate wider ranges of environmental factors. This may explain the low number of oligochaete species. On the other hand, Plathelminthes seem to adapt to relatively narrow ranges of factors and their species richness is highest. Because of macrofaunameiofauna interaction it is suggested that the meiofaunal assemblage will be least stable in mud and muddy sand, and most stable in exposed sand.

  7. Effects of beach cast cleaning on beach quality, microbial food web, and littoral macrofaunal biodiversity

    NASA Astrophysics Data System (ADS)

    Malm, Torleif; Råberg, Sonja; Fell, Sabine; Carlsson, Per

    2004-06-01

    At the end of the summer, drifting filamentous red algae cover shallow bottoms and accumulate in huge cast walls on the open shores of the non-tidal central Baltic Sea. The hypotheses that beach cleaning increases water clarity, decreases the organic content of the sand, and increases the species diversity in the shallow zone closest to the shore, were tested through field investigations and experiments. Cleaned shorelines were compared with un-cleaned shorelines at two sites with different intensity of beach cleaning in a rural area of SE Sweden. The results show that water clarity was significantly increased off the intensively cleaned beach but not off the moderately cleaned one. Similarly, the total leakage of nitrogenous compounds decreased off the intensively cleaned beach, but not off the moderately cleaned. The organic content of the sand was lower on both cleaned beaches compared with nearby un-cleaned beaches. The total animal biomass was significantly lower on the intensively cleaned beach compared with the un-cleaned beach, but the moderately cleaned beach gave no such effect. The difference in biodiversity and community structure between cleaned and un-cleaned beaches was insignificant. The most obvious difference in species composition was a much higher number of planktivore opossum shrimps of the genus Mysis and Praunus on the un-cleaned beaches. The bacterial production and the amount of ciliates larger than 20 mm were also higher on un-cleaned beaches, indicating that the microbial food web off the un-cleaned beaches is stimulated by the discharge of decomposing algal material. The conclusion of the study is that mechanical cleaning reduces the organic content of the beach sand and may change the water quality and microbial production, but the effect on the macrofaunal biodiversity is insignificant.

  8. Southwest Washington littoral drift restoration—Beach and nearshore morphological monitoring

    USGS Publications Warehouse

    Stevens, Andrew W.; Gelfenbaum, Guy; Ruggiero, Peter; Kaminsky, George M.

    2012-01-01

    A morphological monitoring program has documented the placement and initial dispersal of beach nourishment material (280,000 m3) placed between the Mouth of the Columbia River (MCR) North Jetty and North Head, at the southern end of the Long Beach Peninsula in southwestern Washington State. A total of 21 topographic surveys and 8 nearshore bathymetric surveys were performed between July 11, 2010, and November 4, 2011. During placement, southerly alongshore transport resulted in movement of nourishment material to the south towards the MCR North Jetty. Moderate wave conditions (significant wave height around 4 m) following the completion of the nourishment resulted in cross-shore sediment transport, with most of the nourishment material transported into the nearshore bars. The nourishment acted as a buffer to the more severe erosion, including dune overtopping and retreat, that was observed at the northern end of the study area throughout the winter. One year after placement of the nourishment, onshore transport and beach recovery were most pronounced within the permit area and to the south toward the MCR North Jetty. This suggests that there is some long-term benefit of the nourishment for reducing erosion rates locally, although the enhanced recovery also could be due to natural gradients in alongshore transport causing net movement of the sediment from north to south. Measurements made during the morphological monitoring program documented the seasonal movement and decay of nearshore sand bars. Low-energy conditions in late summer resulted in onshore bar migration early in the monitoring program. Moderate wave conditions in the autumn resulted in offshore movement of the middle bar and continued onshore migration of the outer bar. High-energy wave conditions early in the winter resulted in strong cross-shore transport and creation of a 3-bar system along portions of the coast. More southerly wave events occurred later in the winter and early spring and coincided with the complete loss of the outer bar and net loss of sediment from the study area. These data suggest that bar decay may be an important mechanism for exporting sediment from Benson Beach north to the Long Beach Peninsula. The measurements presented in this report represent one component of a broader monitoring program designed to track the movement of nourishment material on the beach and shoreface at this location, including continuous video monitoring (Argus), in situu measurements of hydrodynamics, and a physical tracer experiment. Field data from the monitoring program will be used to test numerical models of hydrodynamics and sediment transport and to improve the capability of numerical models to support regional sediment management.

  9. Calcite-impregnated defluidization structures in littoral sands of mono lake, california.

    PubMed

    Cloud, P; Lajoie, K R

    1980-11-28

    Associated locally with well-known tufa mounds and towers of Mono Lake, California, are subvertical, concretionary sand structures through which fresh calcium-containing artesian waters moved up to sites of calcium carbonate precipitation beneath and adjacent to the lake. The structures include closely spaced calcite-impregnated columns, tubes, and other configurations with subcylindrical to bizarre cross sections and predominantly vertical orientation in coarse, barely coherent pumice sands along the south shore of the lake. Many structures terminate upward in extensive calcareous layers of caliche and tufa. Locally they enter the bases of tufa mounds and towers. A common form superficially resembles root casts and animal burrows except that branching is mostly up instead of down. Similar defluidization structures in ancient sedimentary rocks have been mistakenly interpreted as fossil burrows. PMID:17797491

  10. Functional changes in littoral macroinvertebrate communities in response to watershed-level anthropogenic stress.

    PubMed

    Kovalenko, Katya E; Brady, Valerie J; Ciborowski, Jan J H; Ilyushkin, Sergey; Johnson, Lucinda B

    2014-01-01

    Watershed-scale anthropogenic stressors have profound effects on aquatic communities. Although several functional traits of stream macroinvertebrates change predictably in response to land development and urbanization, little is known about macroinvertebrate functional responses in lakes. We assessed functional community structure, functional diversity (Rao's quadratic entropy) and voltinism in macroinvertebrate communities sampled across the full gradient of anthropogenic stress in Laurentian Great Lakes coastal wetlands. Functional diversity and voltinism significantly decreased with increasing development, whereas agriculture had smaller or non-significant effects. Functional community structure was affected by watershed-scale development, as demonstrated by an ordination analysis followed by regression. Because functional community structure affects energy flow and ecosystem function, and functional diversity is known to have important implications for ecosystem resilience to further environmental change, these results highlight the necessity of finding ways to remediate or at least ameliorate these effects. PMID:25006811

  11. Lake shore and littoral habitat structure: a field survey method and its precision

    EPA Science Inventory

    Until recently, lake physical habitat assessment has been and underemployed tool for assessing lake and reservoir ecological condition. Herein, we outline and evaluate a rapid (2 persons: 1.5-3.5 h) field sampling and analytical approach for quantifying near-shore physical habit...

  12. Lake Shore and Littoral Habitat Structure: Precision and biological Relevance of a Field Survey Method.

    EPA Science Inventory

    Until recently, lake physical habitat assessment has been an underemployed tool for assessing lake and reservoir ecological condition. We outline and evaluate a rapid field sampling and analytical approach for quantifying near-shore physical habitat. We quantified the repeatabil...

  13. Biocenotic composition of the macrozoobenthos on different habitats from the littoral region of Lake Ohrid.

    PubMed

    Smiljkov, Stoe; Trajanovski, Saso; Budzakoska-Goreska, Biljana

    2005-12-01

    Biocenotic research on the benthic fauna from the northwestern part of Lake Ohrid, has shown that different habitats characterize different qualitative compositions of the benthic fauna. The affinity of the macrozoobenthic communities to populate different habitats was investigated in 5 different localities from the northwestern part of Lake Ohrid. Among the five different types of habitats such as stony bottom, sandy bottom, sandy-muddy bottom and muddy bottom mostly covered with mollusc shells, it was found that from the qualitative point of view, the sandy-muddy bottom covered with vascular macrophytes is characterized with highest biodiversity of benthic fauna. In all localities, with the exclusion of the locality As (where the macrophytic vegetation is not well developed), the maximum number of species was recorded between depth points from 3 to 11 m. In the Radozda locality, the maximum number of species (11 species) was recorded at a depth point of 6m., on a bottom covered with sandy mud. In the Livadishte locality, the highest biodiversity (13 species) was recorded at a depth points of 5 and 11 m., on bottom covered with sandy mud with well developed macrophytic vegetation. The localities Kalista and Struga, the maximum number of species (14 in Kalista and 11 in Struga) was also recorded in the same type of habitat, a sandy-muddy bottom with well developed macrophytic vegetation. PMID:16400236

  14. Evaluating long-term trends in littoral benthic macroinvertebrate communities of lakes recovering from acid deposition.

    PubMed

    Lento, Jennifer; Dillon, Peter J; Somers, Keith M

    2012-12-01

    The Mann-Kendall test has been proposed as a nonparametric method to evaluate trends in long-term water quality datasets with missing values, serial correlation, and non-normality. However, this test has rarely been used to evaluate long-term trends in biological data. In this study, we used the Mann-Kendall test to evaluate trends in 15 years of data on benthic macroinvertebrate communities from 17 Precambrian Shield lakes. We also used the van Belle and Hughes test of trend homogeneity to assess whether common among-lake temporal trends existed. We assumed that evidence of a common regional trend among lakes would support the hypothesis of long-term biological recovery from past acidification. We found decreasing proportions of Chironomidae and increasing proportions of Ephemeroptera, Plecoptera, and Trichoptera (EPT) in both single-lake and multi-lake trend analysis. Moreover, six of the nine lakes with significant trends in more than one benthos metric displayed a significant decrease in Chironomidae and increase in EPT concurrently, indicating a shift towards more acid-sensitive taxa. Weak trends in several of the biological metrics indicated that recovery in these lakes has been impeded. Results of this study indicate that the Mann-Kendall and van Belle and Hughes trend tests are useful statistical tools to evaluate long-term patterns in biological data. PMID:22193633

  15. Tide-associated biological rhythms of some white sea littoral invertebrates.

    NASA Astrophysics Data System (ADS)

    Gusev, O. A.; Golubev, A. I.

    2001-01-01

    We report the results from two years of laboratory observations of the tide-associated rhythms of activity of White Sea intertidal invertebrates, Mya arenaria (Bivalvia) and Gammarus finmarchicus (Amphipoda). The tidal associated activity of these invertebrates could not be estimate as a clear circatidal clock. Gammarus activity could be phase shifted by a 0.5 h exposure to turbulent water twice a day for 2-3 days. Mya's rhythm could be changed by a single drainage of aquariums lasting about 15 min. This kind of timing system may be a relatively primitive evolution feature.

  16. Marine litter in Mediterranean sandy littorals: Spatial distribution patterns along central Italy coastal dunes.

    PubMed

    Poeta, Gianluca; Battisti, Corrado; Acosta, Alicia T R

    2014-12-15

    Sandy shores are generally considered important sinks for marine litter and the presence of this litter may represent a serious threat to biotic communities and dune integrity mostly due to cleaning activities carried out through mechanical equipment. In spring (April-May) 2012 we sampled 153 2×2m random plots to assess the spatial distribution patterns of litter on Central Italy sandy shores. We analysed the relationship between the presence of litter and coastal dune habitats along the sea-inland gradient. Our results showed that the most frequent litter items were plastic and polystyrene. Differences of marine litter spatial distribution were found between upper beach and fore dune habitats and fixed dune habitats: embryo dune and mobile dune habitats show the highest frequency of litter, but, surprisingly, marine litter did not impact fixed dune habitats, these possibly acting as a natural barrier protecting the inner part of the coast from marine litter dispersion. PMID:25455823

  17. Calcite-impregnated defluidization structures in littoral sands of Mono Lake, California

    USGS Publications Warehouse

    Cloud, P.; Lajoie, K.R.

    1980-01-01

    Associated locally with well-known tufa mounds and towers of Mono Lake, California, are subvertical, concretionary sand structures through which fresh calcium-containing artesian waters moved up to sites of calcium carbonate precipitation beneath and adjacent to the lake. The structures include closely spaced calcite-impregnated columns, tubes, and other configurations with subcylindrical to bizarre cross sections and predominantly vertical orientation in coarse, barely coherent pumice sands along the south shore of the lake. Many structures terminate upward in extensive calcareous layers of caliche and tufa. Locally they enter the bases of tufa mounds and towers. A common form superficially resembles root casts and animal burrows except that branching is mostly up instead of down. Similar defluidization structures in ancient sedimentary rocks have been mistakenly interpreted as fossil burrows.

  18. Littoral transport in the surf zone elucidated by an Eulerian sediment tracer.

    USGS Publications Warehouse

    Duane, D.B.; James, W.R.

    1980-01-01

    An Eulerian, or time integration, sand tracer experiment was designed and carried out in the surf zone near Pt. Mugu, California on April 19, 1972. Data indicate that conditions of stationarity and finite boundaries required for proper application of Eulerian tracer theory exist for short time periods in the surf zone. Grain counts suggest time required for tracer sand to attain equilibrium concentration is on the order of 30-60 minutes. Grain counts also indicate transport (discharge) was strongly dependent upon grain size, with the maximum rate occurring in the size 2.5-2.75 phi, decreasing to both finer and coarser sizes. The measured instantaneous transport was at the annual rate of 2.4 x 106 m3/yr.- Authors

  19. Trophic interactions between native and introduced fish species in a littoral fish community.

    PubMed

    Monroy, M; Maceda-Veiga, A; Caiola, N; De Sostoa, A

    2014-11-01

    The trophic interactions between 15 native and two introduced fish species, silverside Odontesthes bonariensis and rainbow trout Oncorhynchus mykiss, collected in a major fishery area at Lake Titicaca were explored by integrating traditional ecological knowledge and stable-isotope analyses (SIA). SIA suggested the existence of six trophic groups in this fish community based on δ(13)C and δ(15)N signatures. This was supported by ecological evidence illustrating marked spatial segregation between groups, but a similar trophic level for most of the native groups. Based on Bayesian ellipse analyses, niche overlap appeared to occur between small O. bonariensis (<90 mm) and benthopelagic native species (31.6%), and between the native pelagic killifish Orestias ispi and large O. bonariensis (39%) or O. mykiss (19.7%). In addition, Bayesian mixing models suggested that O. ispi and epipelagic species are likely to be the main prey items for the two introduced fish species. This study reveals a trophic link between native and introduced fish species, and demonstrates the utility of combining both SIA and traditional ecological knowledge to understand trophic relationships between fish species with similar feeding habits. PMID:25263642

  20. Reprogrammed pluripotent stem cells from somatic cells.

    PubMed

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-06-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-like pluripotency by transferring somatic cell nuclei into oocytes, by cell fusion with pluripotent cells. Retroviral-mediated introduction of four factors, Oct4, Sox2, Klf4 and c-Myc can successfully reprogram somatic cells into ES cell-like pluripotent stem cells, known as induced pluripotent stem (iPS) cells. These cells closely resemble ES cells in gene expression pattern, cell biologic and phenotypic characteristics. However, to reach the eventual goal of clinical application, it is necessary to overcome the major drawbacks such as low reprogramming efficiency and genomic alterations due to viral integration. In this review, we discuss the current reprogramming techniques and mechanisms of nuclear reprogramming induced by transcription factor transduction. PMID:24298328

  1. Ghost cell lesions

    PubMed Central

    Rajesh, E.; Jimson, Sudha; Masthan, K. M. K.; Balachander, N.

    2015-01-01

    Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms. PMID:26015694

  2. Crystalline Silicon Solar Cells

    NASA Astrophysics Data System (ADS)

    Green, Martin A.

    2015-10-01

    The following sections are included: * Overview * Silicon cell development * Substrate production * Cell processing * Cell costs * Opportunities for improvement * Silicon-supported thin films * Summary * Acknowledgement * References

  3. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). ... abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  4. Red blood cells, sickle cells (image)

    MedlinePlus

    These crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out clearly against the normal round RBCs. These abnormally shaped cells may become entangled and ...

  5. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). The abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  6. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  7. Robotic adherent cell injection for characterizing cell-cell communication.

    PubMed

    Liu, Jun; Siragam, Vinayakumar; Gong, Zheng; Chen, Jun; Fridman, Michael D; Leung, Clement; Lu, Zhe; Ru, Changhai; Xie, Shaorong; Luo, Jun; Hamilton, Robert M; Sun, Yu

    2015-01-01

    Compared to robotic injection of suspended cells (e.g., embryos and oocytes), fewer attempts were made to automate the injection of adherent cells (e.g., cancer cells and cardiomyocytes) due to their smaller size, highly irregular morphology, small thickness (a few micrometers thick), and large variations in thickness across cells. This paper presents a robotic system for automated microinjection of adherent cells. The system is embedded with several new capabilities: automatically locating micropipette tips; robustly detecting the contact of micropipette tip with cell culturing surface and directly with cell membrane; and precisely compensating for accumulative positioning errors. These new capabilities make it practical to perform adherent cell microinjection truly via computer mouse clicking in front of a computer monitor, on hundreds and thousands of cells per experiment (versus a few to tens of cells as state of the art). System operation speed, success rate, and cell viability rate were quantitatively evaluated based on robotic microinjection of over 4000 cells. This paper also reports the use of the new robotic system to perform cell-cell communication studies using large sample sizes. The gap junction function in a cardiac muscle cell line (HL-1 cells), for the first time, was quantified with the system. PMID:25073160

  8. Sickle cell test

    MedlinePlus

    The sickle cell test looks for the abnormal hemoglobin in the blood that causes the disease sickle cell anemia . ... if a person has abnormal hemoglobin that causes sickle cell disease and sickle cell trait. Hemoglobin is a ...

  9. Sickle cell anemia

    MedlinePlus

    Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease ... Sickle cell anemia is caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin is a protein inside red blood cells ...

  10. Stem cell glycolipids.

    PubMed

    Yanagisawa, Makoto

    2011-09-01

    Glycolipids are compounds containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety. Because of their expression patterns and the intracellular localization patterns, glycolipids, including stage-specific embryonic antigens (SSEA-3, SSEA-4, and possibly SSEA-1) and gangliosides (e.g., GD3, GD2, and A2B5 antigens), have been used as marker molecules of stem cells. In this review, I will introduce glycolipids expressed in pluripotent stem cells (embryonic stem cells, induced pluripotent stem cells, very small embryonic-like stem cells, amniotic stem cells, and multilineage-differentiating stress enduring cells), multipotent stem cells (neural stem cells, mesenchymal stem cells, fetal liver multipotent progenitor cells, and hematopoietic stem cells), and cancer stem cells (brain cancer stem cells and breast cancer stem cells), and discuss their availability as biomarkers for identifying and isolating stem cells. PMID:21161592

  11. Murine Mueller cells are progenitor cells for neuronal cells and fibrous tissue cells

    SciTech Connect

    Florian, Christian; Langmann, Thomas; Weber, Bernhard H.F.; Morsczeck, Christian

    2008-09-19

    Mammalian Mueller cells have been reported to possess retinal progenitor cell properties and generate new neurons after injury. This study investigates murine Mueller cells under in vitro conditions for their capability of dedifferentiation into retinal progenitor cells. Mueller cells were isolated from mouse retina, and proliferating cells were expanded in serum-containing medium. For dedifferentiation, the cultured cells were transferred to serum-replacement medium (SRM) at different points in time after their isolation. Interestingly, early cell passages produced fibrous tissue in which extracellular matrix proteins and connective tissue markers were differentially expressed. In contrast, aged Mueller cell cultures formed neurospheres in SRM that are characteristic for neuronal progenitor cells. These neurospheres differentiated into neuron-like cells after cultivation on laminin/ornithine cell culture substrate. Here, we report for the first time that murine Mueller cells can be progenitors for both, fibrous tissue cells and neuronal cells, depending on the age of the cell culture.

  12. Electrorefining cell evaluation

    SciTech Connect

    Bronson, M.C.; Thomas, R.L.

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  13. Leydig cells: From stem cells to aging.

    PubMed

    Chen, Haolin; Ge, Ren-Shan; Zirkin, Barry R

    2009-07-10

    Leydig cells are the testosterone-producing cells of the testis. The adult Leydig cell population ultimately develops from undifferentiated mesenchymal-like stem cells present in the interstitial compartment of the neonatal testis. Four distinct stages of adult Leydig cell development have been identified and characterized: stem Leydig cells, progenitor Leydig cells, immature Leydig cells and adult Leydig cells. The stem Leydig cells are undifferentiated cells that are capable of indefinite self-renewal, differentiation, and replenishment of the Leydig cell niche. Progenitor Leydig cells are derived from the stem Leydig cells. These spindle-shaped cells are luteinizing hormone (LH) receptor positive, have high mitotic activity, and produce little testosterone but rather testosterone metabolites. The progenitor Leydig cells give rise to immature Leydig cells which are round, contain large amounts of smooth endoplasmic reticulum, and produce some testosterone but also very high levels of testosterone metabolites. A single division of these cells produces adult Leydig cells, which are terminally differentiated cells that produce high levels of testosterone. As men age, serum testosterone levels decline, and this is associated with alterations in body composition, energy level, muscle strength, physical, sexual and cognitive functions, and mood. In the Brown Norway rat, used extensively as a model for male reproductive aging, age-related reductions in serum testosterone result from significant decline in the ability of aged Leydig cells to produce testosterone in response to LH stimulation. This review describes Leydig cell development and aging. Additionally, the molecular mechanisms by which testosterone synthesis declines with aging are discussed. PMID:19481681

  14. Fuel cells: A handbook

    NASA Astrophysics Data System (ADS)

    Kinoshita, K.; McLarnon, F. R.; Cairns, E. J.

    1988-05-01

    The purpose of this handbook is to present information describing fuel cells that is helpful to scientists, engineers, and technical managers who are not experienced in this technology, as well as to provide an update on the current technical status of the various types of fuel cells. Following the introduction, contents of this handbook are: fuel cell performance variables; phosphoric acid fuel cell; molten carbonate fuel cell; solid oxide fuel cell; alternative fuel cell technologies; fuel cell systems; and concluding remarks.

  15. CORONAL CELLS

    SciTech Connect

    Sheeley, N. R. Jr.; Warren, H. P. E-mail: harry.warren@nrl.navy.mil

    2012-04-10

    We have recently noticed cellular features in Fe XII 193 A images of the 1.2 MK corona. They occur in regions bounded by a coronal hole and a filament channel, and are centered on flux elements of the photospheric magnetic network. Like their neighboring coronal holes, these regions have minority-polarity flux that is {approx}0.1-0.3 times their flux of majority polarity. Consequently, the minority-polarity flux is 'grabbed' by the majority-polarity flux to form low-lying loops, and the remainder of the network flux escapes to connect with its opposite-polarity counterpart in distant active regions of the Sun. As these regions are carried toward the limb by solar rotation, the cells disappear and are replaced by linear plumes projecting toward the limb. In simultaneous views from the Solar Terrestrial Relations Observatory and Solar Dynamics Observatory spacecraft, these plumes project in opposite directions, extending away from the coronal hole in one view and toward the hole in the other view, suggesting that they are sky-plane projections of the same radial structures. We conclude that these regions are composed of closely spaced radial plumes, extending upward like candles on a birthday cake and visible as cells when seen from above. We suppose that a coronal hole has this same discrete, cellular magnetic structure, but that it is not seen until the encroachment of opposite-polarity flux closes part or all of the hole.

  16. Molluscan cells in culture: primary cell cultures and cell lines

    PubMed Central

    Yoshino, T. P.; Bickham, U.; Bayne, C. J.

    2013-01-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome. PMID:24198436

  17. Indium phosphide solar cells

    NASA Technical Reports Server (NTRS)

    Weinberg, Irving

    1991-01-01

    The direction for InP solar cell research; reduction of cell cost; increase of cell efficiency; measurements needed to better understand cell performance; n/p versus p/n; radiation effects; major problems in cell contacting; and whether the present level of InP solar cell research in the USA should be maintained, decreased, or increased were considered.

  18. Endothelial cell Ca2+ increases upon tumor cell contact and modulates cell-cell adhesion.

    PubMed Central

    Pili, R; Corda, S; Passaniti, A; Ziegelstein, R C; Heldman, A W; Capogrossi, M C

    1993-01-01

    The signal transduction mechanisms involved in tumor cell adhesion to endothelial cells are still largely undefined. The effect of metastatic murine melanoma cell and human prostate carcinoma cell contact on cytosolic [Ca2+] of bovine artery endothelial cells was examined in indo-1-loaded endothelial cell monolayers. A rapid increase in endothelial cell [Ca2+] occurred on contact with tumor cells, but not on contact with 8-microns inert beads. A similar increase in endothelial cell [Ca2+] was observed with human neutrophils or monocyte-like lymphoma cells, but not with endothelial cells, red blood cells, and melanoma cell-conditioned medium. The increase in endothelial cell [Ca2+] was not inhibited by extracellular Ca2+ removal. In contrast, endothelial cell pretreatment with thapsigargin, which releases endoplasmic reticulum Ca2+ into the cytosol and depletes this Ca2+ store site, abolished the cytosolic [Ca2+] rise upon melanoma cell contact. Endothelial cell pretreatment with the membrane-permeant form of the Ca2+ chelator bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid blocked the increase in cytosolic [Ca2+]. Under static and dynamic flow conditions (0.46 dyn/cm2) bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid pretreatment of bovine pulmonary artery endothelial cell monolayers inhibited melanoma cell adhesion to the endothelial cells. Thus, tumor cell contact with endothelial cells induces a rapid Ca2+ release from endothelial intracellular stores, which has a functional role in enhancing cell-cell adhesion. Images PMID:8254056

  19. DNA-cell conjugates

    DOEpatents

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  20. Cell-cell interactions on solid matrices.

    PubMed

    Louis, Nancy A; Daniels, Dionne; Colgan, Sean P

    2006-01-01

    Models to study molecular, biochemical, and functional responses in vitro generally incorporate an individual cell type or group of cells organized in a random fashion. Normal physiological responses in vivo require that individual cell types be oriented in an organized fashion with three-dimensional architecture and appropriately positioned cellular interfaces. Much recent progress has been made in the development and implementation of models to study cell-cell contact using substrate grown cells. Here, we summarize the use of membrane permeable supports to study functional responses in appropriately positioned cell types. These models incorporate two or more different cells cultured in physiologically positioned locales on solid substrates. Models incorporating nonadherent cells (e.g., leukocytes) in co-culture with such models also are discussed. Such models have been used extensively to discovery both cell-bound as well as soluble mediators of physiological and pathophysiological processes. PMID:16799188

  1. Photovoltaic cell

    SciTech Connect

    Jordan, J.F.; Lampkin, C.M.

    1981-12-08

    A photovoltaic cell has: an electrically conductive substrate, which may be glass having a film of conductive tin oxide; a first layer containing a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure; a second layer forming a heterojunction with the first layer; and suitable electrodes where the heterojunction is formed from a solution containing copper, the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amporphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  2. Photoelectrochemical cell

    DOEpatents

    Rauh, R. David; Boudreau, Robert A.

    1983-06-14

    A photoelectrochemical cell comprising a sealed container having a light-transmitting window for admitting light into the container across a light-admitting plane, an electrolyte in the container, a photoelectrode in the container having a light-absorbing surface arranged to receive light from the window and in contact with the electrolyte, the surface having a plurality of spaced portions oblique to the plane, each portion having dimensions at least an order of magnitude larger than the maximum wavelength of incident sunlight, the total surface area of the surface being larger than the area of the plane bounded by the container, and a counter electrode in the container in contact with the electrolyte.

  3. Integrated circuit cell library

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor)

    2005-01-01

    According to the invention, an ASIC cell library for use in creation of custom integrated circuits is disclosed. The ASIC cell library includes some first cells and some second cells. Each of the second cells includes two or more kernel cells. The ASIC cell library is at least 5% comprised of second cells. In various embodiments, the ASIC cell library could be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more comprised of second cells.

  4. Monitoring cell growth.

    PubMed

    Strober, W

    2001-05-01

    This appendix provides two protocols for monitoring cell growth. Counting cells using a hemacytometer is tedious but it allows one to effectively distinguish live cells from dead cells (using Trypan Blue exclusion). In addition, this procedure is less subject to errors due to cell clumping or heterogeneity of cell size. The use of an electronic cell counter is quicker and easier than counting cells using a hemacytometer. However, an electronic cell counter as currently constructed does not distinguish live from dead cells in a reliable fashion and is subject to error due to the presence of cell clumps. Overall, the electronic cell counter is best reserved for repetitive and rapid counting of fresh peripheral blood cells and should be used with caution when counting cell populations derived from tissues. PMID:18432653

  5. Automated Cell-Cutting for Cell Cloning

    NASA Astrophysics Data System (ADS)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  6. Eukaryotic Cells and their Cell Bodies: Cell Theory Revised

    PubMed Central

    BALUŠKA, FRANTIŠEK; VOLKMANN, DIETER; BARLOW, PETER W.

    2004-01-01

    • Background Cell Theory, also known as cell doctrine, states that all eukaryotic organisms are composed of cells, and that cells are the smallest independent units of life. This Cell Theory has been influential in shaping the biological sciences ever since, in 1838/1839, the botanist Matthias Schleiden and the zoologist Theodore Schwann stated the principle that cells represent the elements from which all plant and animal tissues are constructed. Some 20 years later, in a famous aphorism Omnis cellula e cellula, Rudolf Virchow annunciated that all cells arise only from pre‐existing cells. General acceptance of Cell Theory was finally possible only when the cellular nature of brain tissues was confirmed at the end of the 20th century. Cell Theory then rapidly turned into a more dogmatic cell doctrine, and in this form survives up to the present day. In its current version, however, the generalized Cell Theory developed for both animals and plants is unable to accommodate the supracellular nature of higher plants, which is founded upon a super‐symplasm of interconnected cells into which is woven apoplasm, symplasm and super‐apoplasm. Furthermore, there are numerous examples of multinucleate coenocytes and syncytia found throughout the eukaryote superkingdom posing serious problems for the current version of Cell Theory. • Scope To cope with these problems, we here review data which conform to the original proposal of Daniel Mazia that the eukaryotic cell is composed of an elemental Cell Body whose structure is smaller than the cell and which is endowed with all the basic attributes of a living entity. A complement to the Cell Body is the Cell Periphery Apparatus, which consists of the plasma membrane associated with other periphery structures. Importantly, boundary stuctures of the Cell Periphery Apparatus, although capable of some self‐assembly, are largely produced and maintained by Cell Body activities and can be produced from it de novo. These

  7. Photovoltaic cell

    SciTech Connect

    Jordan, J. F.; Lampkin, C. M.

    1981-02-03

    A photovoltaic cell is disclosed having an electrically conductive substrate, which may be glass having a film of conductive tin oxide. A first layer contains a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure a second layer forms a heterojunction with the first layer suitable electrodes are provided where the heterojunction is formed from a solution containing copper, and the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amorphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  8. Fuel cell arrangement

    DOEpatents

    Isenberg, Arnold O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber.

  9. Fuel cell arrangement

    DOEpatents

    Isenberg, A.O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber. 3 figs.

  10. Squamous cell carcinoma —

    Cancer.gov

    The hallmarks of squamous cell carcinoma are the differentiation features of the squamous epithelium: keratinization and intercellular bridges. Large central masses of keratin, individual cell keratinization, and/or keratin pearls may form. Necrosis of tumor cell nests and accumulation of acute inflammatory cells are frequent features of poorly differentiated squamous cell carcinoma.

  11. Sickle Cell Anemia

    MedlinePlus

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They don' ... problem causes sickle cell anemia. People with the disease are born with two sickle cell genes, one ...

  12. Sickle Cell Anemia

    MedlinePlus

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They ... last as long as normal, round red blood cells. This leads to anemia. The sickle cells also ...

  13. Virus Cell-to-Cell Transmission▿

    PubMed Central

    Mothes, Walther; Sherer, Nathan M.; Jin, Jing; Zhong, Peng

    2010-01-01

    Viral infections spread based on the ability of viruses to overcome multiple barriers and move from cell to cell, tissue to tissue, and person to person and even across species. While there are fundamental differences between these types of transmissions, it has emerged that the ability of viruses to utilize and manipulate cell-cell contact contributes to the success of viral infections. Central to the excitement in the field of virus cell-to-cell transmission is the idea that cell-to-cell spread is more than the sum of the processes of virus release and entry. This implies that virus release and entry are efficiently coordinated to sites of cell-cell contact, resulting in a process that is distinct from its individual components. In this review, we will present support for this model, illustrate the ability of viruses to utilize and manipulate cell adhesion molecules, and discuss the mechanism and driving forces of directional spreading. An understanding of viral cell-to-cell spreading will enhance our ability to intervene in the efficient spreading of viral infections. PMID:20375157

  14. Cell culture purity issues and DFAT cells

    SciTech Connect

    Wei, Shengjuan; Bergen, Werner G.; Zan, Linsen; Dodson, Michael V.

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  15. Deformability of Tumor Cells versus Blood Cells.

    PubMed

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T; Hecht, Vivian C; Maheswaran, Shyamala; Stott, Shannon L; Toner, Mehmet; Hynes, Richard O; Manalis, Scott R

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  16. Deformability of Tumor Cells versus Blood Cells

    PubMed Central

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T.; Hecht, Vivian C.; Maheswaran, Shyamala; Stott, Shannon L.; Toner, Mehmet; Hynes, Richard O.; Manalis, Scott R.

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  17. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    ... inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  18. Fuel cell-fuel cell hybrid system

    DOEpatents

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  19. Cell Membrane Softening in Cancer Cells

    NASA Astrophysics Data System (ADS)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  20. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1980-01-01

    The following aspects of kidney cell electrophoresis are discussed: (1) the development and testing of electrophoresis solutions; (2) optimization of freezing and thawing; (3) procedures for evaluation of separated kidney cells; and (4) electrophoretic mobility characterization of kidney cells.

  1. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1979-01-01

    A kidney cell electrophoresis technique is described in four parts: (1) the development and testing of electrophoresis solutions; (2) optimization of freezing and thawing; (3) procedures for evaluation of separated kidney cells; and (4) electrophoretic mobility characteristics of kidney cells.

  2. Lung cancer - small cell

    MedlinePlus

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC ...

  3. Sickle Cell Information Center

    MedlinePlus

    ... change Sickle Cell News from Around the Web Google Custom Search – sickle cell Our healthcare system abandons ... professor of ... NYT, Nature, Wash Post, SciAm, CNN - Google Custom Search Sickle Cell Anemia News -- ScienceDaily January ...

  4. Lung cancer - small cell

    MedlinePlus

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  5. Fuel cells: A survey

    NASA Technical Reports Server (NTRS)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  6. Advances in cell culture

    SciTech Connect

    Maramorosch, K. )

    1987-01-01

    This book presents papers on advances in cell culture. Topics covered include: Genetic changes in the influenza viruses during growth in cultured cells; The biochemistry and genetics of mosquito cells in culture; and Tree tissue culture applications.

  7. Sickle cell anemia - resources

    MedlinePlus

    Resources - sickle cell anemia ... The following organizations are good resources for information on sickle cell anemia : American Sickle Cell Anemia Association -- www.ascaa.org National Heart, Blood, and Lung Institute -- www. ...

  8. Reprogramming of somatic cells.

    PubMed

    Rajasingh, Johnson

    2012-01-01

    Reprogramming of adult somatic cells into pluripotent stem cells may provide an attractive source of stem cells for regenerative medicine. It has emerged as an invaluable method for generating patient-specific stem cells of any cell lineage without the use of embryonic stem cells. A revolutionary study in 2006 showed that it is possible to convert adult somatic cells directly into pluripotent stem cells by using a limited number of pluripotent transcription factors and is called as iPS cells. Currently, both genomic integrating viral and nonintegrating nonviral methods are used to generate iPS cells. However, the viral-based technology poses increased risk of safety, and more studies are now focused on nonviral-based technology to obtain autologous stem cells for clinical therapy. In this review, the pros and cons of the present iPS cell technology and the future direction for the successful translation of this technology into the clinic are discussed. PMID:22917226

  9. Inside the Cell

    MedlinePlus

    ... Business Basics Describes functions shared by virtually all cells: making fuel and proteins, transporting materials and disposing of wastes. » more Chapter 3: On the Job: Cellular Specialties Explains how cells specialize. Features a number of cell types: nerves, ...

  10. Closed Large Cell Clouds

    Atmospheric Science Data Center

    2013-04-19

    article title:  Closed Large Cell Clouds in the South Pacific     ... unperturbed by cyclonic or frontal activity. When the cell centers are cloudy and the main sinking motion is concentrated at cell ...

  11. Pancreatic islet cell tumor

    MedlinePlus

    Islet cell tumors; Islet of Langerhans tumor; Neuroendocrine tumors ... In the healthy pancreas, cells called islet cells produce hormones that regulate a several bodily functions. These include blood sugar level and the production of ...

  12. Sickle Cell Disease Quiz

    MedlinePlus

    ... False: People with sickle cell disease cannot get malaria. A True B False 4. True or False: ... False: People with sickle cell disease cannot get malaria. False People with sickle cell disease can get ...

  13. Glial cells: Old cells with new twists

    PubMed Central

    Ndubaku, Ugo; de Bellard, Maria Elena

    2008-01-01

    Summary Based on their characteristics and function – migration, neural protection, proliferation, axonal guidance and trophic effects – glial cells may be regarded as probably the most versatile cells in our body. For many years, these cells were considered as simply support cells for neurons. Recently, it has been shown that they are more versatile than previously believed – as true stem cells in the nervous system – and are important players in neural function and development. There are several glial cell types in the nervous system: the two most abundant are oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system. Although both of these cells are responsible for myelination, their developmental origins are quite different. Oligodendrocytes originate from small niche populations from different regions of the central nervous system, while Schwann cells develop from a stem cell population (the neural crest) that gives rise to many cell derivatives besides glia and which is a highly migratory group of cells. PMID:18068219

  14. CellFinder: a cell data repository

    PubMed Central

    Stachelscheid, Harald; Seltmann, Stefanie; Lekschas, Fritz; Fontaine, Jean-Fred; Mah, Nancy; Neves, Mariana; Andrade-Navarro, Miguel A.; Leser, Ulf; Kurtz, Andreas

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue types from RNA-seq and microarrays and 553 905 protein expressions for 535 cells/tissues. Text mining of a corpus of >2000 publications followed by manual curation confirmed expression information on ∼900 proteins and genes. CellFinder’s data model is capable to seamlessly represent entities from single cells to the organ level, to incorporate mappings between homologous entities in different species and to describe processes of cell development and differentiation. Its ontological backbone currently consists of 204 741 ontology terms incorporated from 10 different ontologies unified under the novel CELDA ontology. CellFinder’s web portal allows searching, browsing and comparing the stored data, interactive construction of developmental trees and navigating the partonomic hierarchy of cells and tissues through a unique body browser designed for life scientists and clinicians. PMID:24304896

  15. Snail modulates cell metabolism in MDCK cells

    SciTech Connect

    Haraguchi, Misako; Indo, Hiroko P.; Iwasaki, Yasumasa; Iwashita, Yoichiro; Fukushige, Tomoko; Majima, Hideyuki J.; Izumo, Kimiko; Horiuchi, Masahisa; Kanekura, Takuro; Furukawa, Tatsuhiko; Ozawa, Masayuki

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  16. Sertoli cells as biochambers

    NASA Technical Reports Server (NTRS)

    Cameron, Don F. (Inventor); Sanberg, Paul R. (Inventor); Saporta, Samuel (Inventor); Hushen, Joelle J. (Inventor)

    2004-01-01

    According to the present invention, there is provided a biological chamber system having a biochamber defined by outer walls of Sertoli cells. Also provided is a transplantation facilitator including a biochamber. A method of making biochambers by co-culturing facilitator cells and therapeutic cells and then aggregating the facilitator celes is also provided. Also provided is a method of transplanting cells by incorporating transplant cells into a biochamber and transplanting the biochamber containing the transplant cells.

  17. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2009-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  18. Heterostructure solar cells

    NASA Technical Reports Server (NTRS)

    Chang, K. I.; Yeh, Y. C. M.; Iles, P. A.; Morris, R. K.

    1987-01-01

    The performance of gallium arsenide solar cells grown on Ge substrates is discussed. In some cases the substrate was thinned to reduce overall cell weight with good ruggedness. The conversion efficiency of 2 by 2 cm cells under AMO reached 17.1 percent with a cell thickness of 6 mils. The work described forms the basis for future cascade cell structures, where similar interconnecting problems between the top cell and the bottom cell must be solved. Applications of the GaAs/Ge solar cell in space and the expected payoffs are discussed.

  19. Stem Cell Research

    SciTech Connect

    Verfaillie, Catherine

    2002-01-23

    We have identified a population of primitive cells in normal human post-natal bone marrow that can, at the single cell level, differentiate in many ways and also proliferate extensively. These cells can differentiate in vitro into most mesodermal cell types (for example, bone cells, and others), as well as cells into cells of the nervous system. The finding that stem cells exist in post-natal tissues with previously unknown proliferation and differentiation potential opens up the possibility of using them to treat a host of degenerative, traumatic or congenital diseases.

  20. Gaucher cell, photomicrograph (image)

    MedlinePlus

    Gaucher's disease is called a "lipid storage disease" where abnormal amounts of lipids called "glycosphingolipids" are stored in special cells called reticuloendothelial cells. Classically, the nucleus is ...

  1. Cell heterogeneity during the cell cycle

    SciTech Connect

    Darzynkiewicz, Z.; Crissman, H.; Traganos, F.; Steinkamp, J.

    1982-12-01

    Using flow cytometry, populations of Chinese hamster ovary cells, asynchronous and synchronized in the cycle, were measured with respect to cellular RNA- and protein-content, as well as cell light scatter properties. Heterogeneities of cell populations were expressed as coefficients of variation (c.v.) in percent of the respective mean values. Populations of cells immediately after mitosis have about 15% higher c.v. than mitotic cell populations, regardless of whether RNA, proteins, or light scatter are measured. These data indicate that cytoplasmic constituents are unequally distributed into the daughter cells during cytokinesis and that unequal cytokinesis generates intercellular metabolic variability during the cycle. An additional increase in heterogeneity, although of smaller degree, occurs during G/sub 2/ phase. Populations of S-phase cells are the most uniform, having 20-30% lower c.v. than the postmitotic cells. Cell progression through S does not involve any significant increase in intercellular variability with respect to RNA or protein content. In unperturbed exponentially growing cultures a critical RNA content is required for G/sub 1/ cells prior to their entrance into S. The cell residence times in the equalization compartments are exponentially distributed, which may reflect the randomness generated by the uneven division of metabolic constituents to daughter cells during cytokinesis. The cell heterogeneities were presently estimated at two metabolic levels, transcription (RNA content) and translation (proteins). The most uniform were populations stained for RNA and the highest variability was observed after staining of proteins. This suggests that the regulatory mechanisms equalizing cells in the cell cycle may operate primarily at the level of DNA transcription.

  2. Stem cells supporting other stem cells

    PubMed Central

    Leatherman, Judith

    2013-01-01

    Adult stem cell therapies are increasingly prevalent for the treatment of damaged or diseased tissues, but most of the improvements observed to date are attributed to the ability of stem cells to produce paracrine factors that have a trophic effect on existing tissue cells, improving their functional capacity. It is now clear that this ability to produce trophic factors is a normal and necessary function for some stem cell populations. In vivo adult stem cells are thought to self-renew due to local signals from the microenvironment where they live, the niche. Several niches have now been identified which harbor multiple stem cell populations. In three of these niches – the Drosophila testis, the bulge of the mammalian hair follicle, and the mammalian bone marrow – one type of stem cell has been found to produce factors that contribute to the maintenance of a second stem cell population in the shared niche. In this review, I will examine the architecture of these three niches and discuss the molecular signals involved. Together, these examples establish a new paradigm for stem cell behavior, that stem cells can promote the maintenance of other stem cells. PMID:24348512

  3. Cell and tissue mechanics in cell migration

    PubMed Central

    Lange, Janina R.; Fabry, Ben

    2013-01-01

    Migrating cells generate traction forces to counteract the movement-resisting forces arising from cell-internal stresses and matrix adhesions. In the case of collective migration in a cell colony, or in the case of 3-dimensional migration through connective tissue, movement-resisting forces arise also from external stresses. Although the deformation of a stiffer cell or matrix causes larger movement-resisting forces, at the same time a larger stiffness can also promote cell migration due to a feedback between forces, deformations, and deformation speed that is mediated by the acto-myosin contractile machinery of cells. This mechanical feedback is also important for stiffness sensing, durotaxis, plithotaxis, and collective migration in cell colonies. PMID:23664834

  4. Cell and tissue mechanics in cell migration.

    PubMed

    Lange, Janina R; Fabry, Ben

    2013-10-01

    Migrating cells generate traction forces to counteract the movement-resisting forces arising from cell-internal stresses and matrix adhesions. In the case of collective migration in a cell colony, or in the case of 3-dimensional migration through connective tissue, movement-resisting forces arise also from external stresses. Although the deformation of a stiffer cell or matrix causes larger movement-resisting forces, at the same time a larger stiffness can also promote cell migration due to a feedback between forces, deformations, and deformation speed that is mediated by the acto-myosin contractile machinery of cells. This mechanical feedback is also important for stiffness sensing, durotaxis, plithotaxis, and collective migration in cell colonies. PMID:23664834

  5. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    SciTech Connect

    Felthaus, O.; Ettl, T.; Gosau, M.; Driemel, O.; Brockhoff, G.; Reck, A.; Zeitler, K.; Hautmann, M.; Reichert, T.E.; Schmalz, G.; Morsczeck, C.

    2011-04-01

    Research highlights: {yields} Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). {yields} Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. {yields} Monoclonal cell lines showed reduced sensitivity for Paclitaxel. {yields} In situ CD133{sup +} cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. {yields} CD133{sup +} and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133{sup +} cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  6. The offshore export of sand during exceptional discharge from California rivers

    USGS Publications Warehouse

    Warrick, Jonathan A.; Barnard, Patrick L.

    2012-01-01

    Littoral cells along active tectonic margins receive large inputs of sand and gravel from coastal watersheds and commonly lose this sediment to submarine canyons. One hypothesis is that the majority of coarse (sand and gravel) river sediment discharge will be emplaced within and immediately “resupply” local littoral cells. A competing hypothesis is that the infrequent, large floods that supply the majority of littoral sediment may discharge water-sediment mixtures within negatively buoyant hyperpycnal plumes that transport sediment offshore of the littoral cell. Here we summarize pre- and post-flood surveys of two wave-dominated California (United States) river deltas during record to near-record floods to help evaluate these hypotheses: the 1982–1983 delta at the San Lorenzo River mouth and the 2005 delta at the Santa Clara River mouth. Flood sedimentation at both deltas resulted in several meters of aggradation and hundreds of meters of offshore displacement of isobaths. One substantial difference between these deltas was the thick (>2 m) aggradation of sand on the inner shelf of the Santa Clara River delta that contained substantial amounts (∼50%) of littoral-grade sediment. Once deposited on the inner shelf, only a fraction (∼20%) of this river sand was observed to migrate toward the beach over the following 5 yr. Furthermore, simple hypopycnal plume behavior could not explain deposition of this sand on the inner shelf. Thus, during an exceptional flood a substantial amount of littoral-grade sand was exported offshore of the littoral system at the Santa Clara River mouth—likely from hyperpycnal plume processes—and was deposited on the inner shelf.

  7. Specific cell cycle synchronization with butyrate and cell cycle analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synchronized cells have been invaluable for many kinds of cell cycle and cell proliferation studies. Butyrate induces cell cycle arrest and apoptosis in MDBK cells. To explore the possibility of using butyrate-blocked cells to obtain synchronized cells, we investigated the property of the cell cyc...

  8. Stem cell therapy without the cells

    PubMed Central

    Maguire, Greg

    2013-01-01

    As an example of the burgeoning importance of stem cell therapy, this past month the California Institute for Regenerative Medicine (CIRM) has approved $70 million to create a new network of stem cell clinical trial centers. Much work in the last decade has been devoted to developing the use of autologous and allogeneic adult stem cell transplants to treat a number of conditions, including heart attack, dementia, wounds, and immune system-related diseases. The standard model teaches us that adult stem cells exists throughout most of the body and provide a means to regenerate and repair most tissues through replication and differentiation. Although we have often witnessed the medical cart placed in front of the scientific horse in the development of stem cell therapies outside of academic circles, great strides have been made, such as the use of purified stem cells1 instead of whole bone marrow transplants in cancer patients, where physicians avoid re-injecting the patients with their own cancer cells.2 We most often think of stem cell therapy acting to regenerate tissue through replication and then differentiation, but recent studies point to the dramatic effects adult stem cells exert in the repair of various tissues through the release of paracrine and autocrine substances, and not simply through differentiation. Indeed, up to 80% of the therapeutic effect of adult stem cells has been shown to be through paracrine mediated actions.3 That is, the collected types of molecules released by the stem cells, called the secretome, or stem cell released molecules (SRM), number in the 100s, including proteins, microRNA, growth factors, antioxidants, proteasomes, and exosomes, and target a multitude of biological pathways through paracrine actions. The composition of the different molecule types in SRM is state dependent, and varies with cell type and conditions such as age and environment. PMID:24567776

  9. Sickle Cell Disease

    MedlinePlus

    ... sickle cell disease? Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... or blocks blood and oxygen reaching nearby tissues. Sickle cell disease ... the whites of the eyes) Anemia (the decreased ability of the blood to carry ...

  10. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    SciTech Connect

    Varga, Nora; Vereb, Zoltan; Rajnavoelgyi, Eva; Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs; Apati, Agota

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  11. SMOOTH MUSCLE STEM CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  12. Nanocomposite Photoelectrochemical Cells

    NASA Technical Reports Server (NTRS)

    Narayan, Sri R.; Kindler, Andrew; Whitacre, Jay F.

    2007-01-01

    Improved, solid-state photoelectrochemical cells for converting solar radiation to electricity have been proposed. (In general, photoelectrochemical cells convert incident light to electricity through electrochemical reactions.) It is predicted that in comparison with state-of-the-art photoelectrochemical cells, these cells will be found to operate with greater solar-to-electric energy-conversion efficiencies.

  13. Fluorescence activated cell sorting.

    NASA Technical Reports Server (NTRS)

    Bonner, W. A.; Hulett, H. R.; Sweet, R. G.; Herzenberg, L. A.

    1972-01-01

    An instrument has been developed for sorting biological cells. The cells are rendered differentially fluorescent and incorporated into a small liquid stream illuminated by a laser beam. The cells pass sequentially through the beam, and fluorescent light from the cells gives rise to electrical signals. The stream is broken into a series of uniform size drops downstream of the laser. The cell signals are used to give appropriate electrostatic charges to drops containing the cells. The drops then pass between two charged plates and are deflected to appropriate containers. The system has proved capable of providing fractions containing large numbers of viable cells highly enriched in a particular functional type.

  14. Molten carbonate fuel cell

    DOEpatents

    Kaun, T.D.; Smith, J.L.

    1986-07-08

    A molten electrolyte fuel cell is disclosed with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas. The cell enclosures collectively provide an enclosure for the array and effectively avoid the problems of electrolyte migration and the previous need for compression of stack components. The fuel cell further includes an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  15. Molten carbonate fuel cell

    DOEpatents

    Kaun, Thomas D.; Smith, James L.

    1987-01-01

    A molten electrolyte fuel cell with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas, the cell enclosures collectively providing an enclosure for the array and effectively avoiding the problems of electrolyte migration and the previous need for compression of stack components, the fuel cell further including an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  16. Jameson cell coal flotation

    SciTech Connect

    Manlapig, E.V.; Jackson, B.R.; Harbort, G.J.; Cheng, C.Y.

    1993-12-31

    Jameson cells have been applied to coal flotation recent years. Some coal mines have Jameson cells in operation, some are having Jameson cells installed and others are considering to use Jameson cells in their flotation circuits. As an example, the application of Jameson cells in Newlands Coal Mine is described and the performance of the Jameson Cell is summarized. It has been demonstrated that the Jameson Cell performs well with minimum supervision and maintenance. The test work conducted at the University of Queensland and Blackwater Coal Mine has showed that the Jameson Cell performed consistently well at all testing conditions. The parallel tests have demonstrated that the Jameson Cell is superior over the conventional cells.

  17. Modeling collective cell motility

    NASA Astrophysics Data System (ADS)

    Rappel, Wouter-Jan

    Eukaryotic cells often move in groups, a critical aspect of many biological and medical processes including wound healing, morphogenesis and cancer metastasis. Modeling can provide useful insights into the fundamental mechanisms of collective cell motility. Constructing models that incorporate the physical properties of the cells, however, is challenging. Here, I discuss our efforts to build a comprehensive cell motility model that includes cell membrane properties, cell-substrate interactions, cell polarity, and cell-cell interaction. The model will be applied to a variety of systems, including motion on micropatterned substrates and the migration of border cells in Drosophila. This work was supported by NIH Grant No. P01 GM078586 and NSF Grant No. 1068869.

  18. Fuel cells seminar

    SciTech Connect

    1996-12-01

    This year`s meeting highlights the fact that fuel cells for both stationary and transportation applications have reached the dawn of commercialization. Sales of stationary fuel cells have grown steadily over the past 2 years. Phosphoric acid fuel cell buses have been demonstrated in urban areas. Proton-exchange membrane fuel cells are on the verge of revolutionizing the transportation industry. These activities and many more are discussed during this seminar, which provides a forum for people from the international fuel cell community engaged in a wide spectrum of fuel cell activities. Discussions addressing R&D of fuel cell technologies, manufacturing and marketing of fuel cells, and experiences of fuel cell users took place through oral and poster presentations. For the first time, the seminar included commercial exhibits, further evidence that commercial fuel cell technology has arrived. A total of 205 papers is included in this volume.

  19. Kidney cell electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P. W.

    1985-01-01

    Tasks were undertaken in support of two objectives. They are: (1) to carry out electrophoresis experiments on cells in microgravity; and (2) assess the feasibility of using purified kidney cells from embryonic kidney cultures as a source of important cell products. Investigations were carried out in the following areas: (1) ground based electrophoresis technology; (2) cell culture technology; (3) electrophoresis of cells; (4) urokinase assay research; (5) zero-g electrophoresis; and (6) flow cytometry.

  20. Stem cell biobanks.

    PubMed

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment. PMID:20560026

  1. Technology Status: Fuel Cells and Electrolysis Cells

    NASA Technical Reports Server (NTRS)

    Mcbryar, H.

    1978-01-01

    The status of the baselined shuttle fuel cell as well as the acid membrane fuel cell and space-oriented water electrolysis technologies are presented. The more recent advances in the alkaline fuel cell technology area are the subject of a companion paper. A preliminary plan for the focusing of these technologies towards regenerative energy storage applications in the multi-hundred kilowatt range is also discussed.

  2. Screening of solar cells

    NASA Technical Reports Server (NTRS)

    Appelbaum, J.; Chait, A.; Thompson, D. A.

    1993-01-01

    Because solar cells in a production batch are not identical, screening is performed to obtain similar cells for aggregation into arrays. A common technique for screening is based on a single operating point of the I-V characteristic of the cell, usually the maximum power point. As a result, inferior cell matching may occur at the actual operating points. Screening solar cells based on the entire I-V characteristic will inherently result in more similar cells in the array. An array consisting of more similar cells is likely to have better overall characteristics and more predictable performance. Solar cell screening methods and cell ranking are discussed. The concept of a mean cell is defined as a cell 'best' representing all the cells in the production batch. The screening and ranking of all cells are performed with respect to the mean cell. The comparative results of different screening methods are illustrated on a batch of 50 silicon cells of the Space Station Freedom.

  3. Optimizing stem cell culture.

    PubMed

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-11-01

    Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane. PMID:20803548

  4. Screening of solar cells

    SciTech Connect

    Appelbaum, J.; Chait, A.; Thompson, D.A.

    1993-07-01

    Because solar cells in a production batch are not identical, screening is performed to obtain similar cells for aggregation into arrays. A common technique for screening is based on a single operating point of the I-V characteristic of the cell, usually the maximum power point. As a result, inferior cell matching may occur at the actual operating points. Screening solar cells based on the entire I-V characteristic will inherently result in more similar cells in the array. An array consisting of more similar cells is likely to have better overall characteristics and more predictable performance. Solar cell screening methods and cell ranking are discussed. The concept of a mean cell is defined as a cell 'best' representing all the cells in the production batch. The screening and ranking of all cells are performed with respect to the mean cell. The comparative results of different screening methods are illustrated on a batch of 50 silicon cells of the Space Station Freedom.

  5. Analytical pyrolysis of cells and cell fragments

    SciTech Connect

    Faix, O.; Bertelt, E.

    1995-12-01

    Wood of spruce, beech and birch was disintegrated without chemical pretreatment after 10 minutes of steaming at 110{degrees}C in a laboratory defibrator. Fibers, vessels, and fragments of secondary wall were separated by wet screening. A hydrocylon was used for separation of middle lamellae. By using analytical pyrolysis-GC/MS, parenchymatic cells were found to be richer in lignin than the other cells. The lignin content of middle lamellae was 35% (beech, spruce) and 39% (birch). In agreement with the literature, the S/G ratios of the vessels and middle lamellae was lower than those of the other cells and cell fragments.

  6. The cell biology of planar cell polarity

    PubMed Central

    2014-01-01

    Planar cell polarity (PCP) refers to the coordinated alignment of cell polarity across the tissue plane. Key to the establishment of PCP is asymmetric partitioning of cortical PCP components and intercellular communication to coordinate polarity between neighboring cells. Recent progress has been made toward understanding how protein transport, endocytosis, and intercellular interactions contribute to asymmetric PCP protein localization. Additionally, the functions of gradients and mechanical forces as global cues that bias PCP orientation are beginning to be elucidated. Together, these findings are shedding light on how global cues integrate with local cell interactions to organize cellular polarity at the tissue level. PMID:25349257

  7. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    NASA Astrophysics Data System (ADS)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  8. AB241. Cancer stem cell-like side population cells in clear cell renal cell carcinoma cell line 769P

    PubMed Central

    Huang, Bin; Wang, Dao-Hu; Chen, Jun-Xing; Qiu, Shao-Peng

    2016-01-01

    Background Although cancers are widely considered to be maintained by stem cells, the existence of stem cells in renal cell carcinoma (RCC) has seldom been reported, in part due to the lack of unique surface markers. We here identified cancer stem cell-like cells with side population (SP) phenotype in five human RCC cell lines. Methods We here identified cancer stem cell-like cells with side population (SP) phenotype in five human RCC cell lines. Results Flow cytometry analysis revealed that 769P, a human clear cell RCC cell line, contained the largest amount of SP cells among five cell lines. These 769P SP cells possessed characteristics of proliferation, self-renewal, and differentiation, as well as strong resistance to chemotherapy and radiotherapy that were possibly related to the ABCB1 transporter. In vivo experiments with serial tumor transplantation in mice also showed that 769P SP cells formed tumors in NOD/SCID mice. Conclusions Taken together, these results indicate that 769P SP cells have the properties of cancer stem cells, which may play important roles in tumorigenesis and therapy-resistance of RCC.

  9. Single cell mechanics of keratinocyte cells.

    PubMed

    Lulevich, Valentin; Yang, Hsin-ya; Isseroff, R Rivkah; Liu, Gang-yu

    2010-11-01

    Keratinocytes represent the major cell type of the uppermost layer of human skin, the epidermis. Using AFM-based single cell compression, the ability of individual keratinocytes to resist external pressure and global rupturing forces is investigated and compared with various cell types. Keratinocytes are found to be 6-70 times stiffer than other cell types, such as white blood, breast epithelial, fibroblast, or neuronal cells, and in contrast to other cell types they retain high mechanic strength even after the cell's death. The absence of membrane rupturing peaks in the force-deformation profiles of keratinocytes and their high stiffness during a second load cycle suggests that their unique mechanical resistance is dictated by the cytoskeleton. A simple analytical model enables the quantification of Young's modulus of keratinocyte cytoskeleton, as high as 120-340 Pa. Selective disruption of the two major cytoskeletal networks, actin filaments and microtubules, does not significantly affect keratinocyte mechanics. F-actin is found to impact cell deformation under pressure. During keratinocyte compression, the plasma membrane stretches to form peripheral blebs. Instead of blebbing, cells with depolymerized F-actin respond to pressure by detaching the plasma membrane from the cytoskeleton underneath. On the other hand, the compression force of keratinocytes expressing a mutated keratin (cell line, KEB-7) is 1.6-2.2 times less than that for the control cell line that has normal keratin networks. Therefore, we infer that the keratin intermediate filament network is responsible for the extremely high keratinocyte stiffness and resilience. This could manifest into the rugged protective nature of the human epidermis. PMID:20728993

  10. Plant stem cell niches.

    PubMed

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis. PMID:22404469

  11. Microscale Fuel Cells

    SciTech Connect

    Holladay, Jamie D.; Viswanathan, Vish V.

    2005-11-03

    Perhaprs some of the most innovative work on fuel cells has been the research dedicated to applying silicon fabrication techniques to fuel cells technology creating low power microscale fuel cells applicable to microelectro mechanical systems (MEMS), microsensors, cell phones, PDA’s, and other low power (0.001 to 5 We) applications. In this small power range, fuel cells offer the decoupling of the energy converter from the energy storage which may enable longer operating times and instant or near instant charging. To date, most of the microscale fuel cells being developed have been based on proton exchange membrane fuel cell technology (PEMFC) or direct methanol fuel cell (DMFC) technology. This section will discuss requirements and considerations that need to be addressed in the development of microscale fuel cells, as well as some proposed designs and fabrication strategies.

  12. Tetraspanins in Cell Migration

    PubMed Central

    Jiang, Xupin; Zhang, Jiaping; Huang, Yuesheng

    2015-01-01

    Tetraspanins are a superfamily of small transmembrane proteins that are expressed in almost all eukaryotic cells. Through interacting with one another and with other membrane and intracellular proteins, tetraspanins regulate a wide range of proteins such as integrins, cell surface receptors, and signaling molecules, and thereby engage in diverse cellular processes ranging from cell adhesion and migration to proliferation and differentiation. In particular, tetraspanins modulate the function of proteins involved in all determining factors of cell migration including cell–cell adhesion, cell–ECM adhesion, cytoskeletal protrusion/contraction, and proteolytic ECM remodeling. We herein provide a brief overview of collective in vitro and in vivo studies of tetraspanins to illustrate their regulatory functions in the migration and trafficking of cancer cells, vascular endothelial cells, skin cells (keratinocytes and fibroblasts), and leukocytes. We also discuss the involvement of tetraspanins in various pathologic and remedial processes that rely on cell migration and their potential value as targets for therapeutic intervention. PMID:26091149

  13. Bacterial Cell Wall Components

    NASA Astrophysics Data System (ADS)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  14. Aquaporins and cell migration.

    PubMed

    Papadopoulos, M C; Saadoun, S; Verkman, A S

    2008-07-01

    Aquaporin (AQP) water channels are expressed primarily in cell plasma membranes. In this paper, we review recent evidence that AQPs facilitate cell migration. AQP-dependent cell migration has been found in a variety of cell types in vitro and in mice in vivo. AQP1 deletion reduces endothelial cell migration, limiting tumor angiogenesis and growth. AQP4 deletion slows the migration of reactive astrocytes, impairing glial scarring after brain stab injury. AQP1-expressing tumor cells have enhanced metastatic potential and local infiltration. Impaired cell migration has also been seen in AQP1-deficient proximal tubule epithelial cells, and AQP3-deficient corneal epithelial cells, enterocytes, and skin keratinocytes. The mechanisms by which AQPs enhance cell migration are under investigation. We propose that, as a consequence of actin polymerization/depolymerization and transmembrane ionic fluxes, the cytoplasm adjacent to the leading edge of migrating cells undergoes rapid changes in osmolality. AQPs could thus facilitate osmotic water flow across the plasma membrane in cell protrusions that form during migration. AQP-dependent cell migration has potentially broad implications in angiogenesis, tumor metastasis, wound healing, glial scarring, and other events requiring rapid, directed cell movement. AQP inhibitors may thus have therapeutic potential in modulating these events, such as slowing tumor growth and spread, and reducing glial scarring after injury to allow neuronal regeneration. PMID:17968585

  15. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    PubMed Central

    Liu, Quanwen; Shen, Yi; Chen, Jiarong; Ding, Jie; Tang, Zihua; Zhang, Cui; Chen, Jianling; Li, Liang; Chen, Ping; Wang, Jinfu

    2016-01-01

    In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment. PMID:27057177

  16. Lithium cell test results

    NASA Technical Reports Server (NTRS)

    Bragg, B. J.

    1977-01-01

    Three lithium SO2 cells, two lithium CF cells, and a vinyl chloride cell, all with crimped seals, and all strictly experimental, were independently discharged on resistors. Three temperatures were used and several different storage temperatures. Discharge rate generally on the nominal discharges were 0.1 amp, 0.5 amp, and 1 amp. Tests results show that the crimp seals are inadequate, especially for the SO2 cells. Normal discharges present no hazards. All cells discharge to zero. The problem of lithium cell explosions, such as occurred during off-limits testing, is discussed.

  17. Cell adhesion force microscopy

    PubMed Central

    Sagvolden, G.; Giaever, I.; Pettersen, E. O.; Feder, J.

    1999-01-01

    The adhesion forces of cervical carcinoma cells in tissue culture were measured by using the manipulation force microscope, a novel atomic force microscope. The forces were studied as a function of time and temperature for cells cultured on hydrophilic and hydrophobic polystyrene substrates with preadsorbed proteins. The cells attached faster and stronger at 37°C than at 23°C and better on hydrophilic than on hydrophobic substrates, even though proteins adsorb much better to the hydrophobic substrates. Because cell adhesion serves to control several stages in the cell cycle, we anticipate that the manipulation force microscope can help clarify some cell-adhesion related issues. PMID:9892657

  18. Hydrogen/bromine cell

    SciTech Connect

    Hohne, K.; Starbeck, G.

    1985-05-28

    Described herein is an energy storage device which utilizes a hydrogen/bromine cell. The cell includes a bromine electrode and a hydrogen electrode. The cell is light weight, resists corrosion caused by bromine or hydrobromic acid and uses both an electrolysis and a fuel cell reaction to store or discharge electrical energy. The cell frame is made of graphite and has a pyrographite coating on at least the portion facing the bromine electrode. This cell is therefore very useful in matching varying energy supplies with varying energy demands and allows for decentralization of energy storage.

  19. On cells and size

    NASA Astrophysics Data System (ADS)

    Boudaoud, Arezki

    2002-03-01

    The growth of isolated cells is studied. They are modeled as growing elastic shells submitted to an internal pressure. A scaling law for a preferred radius of curvature is derived. It is in agreement with compiled experimental data over more than orders of magnitude in cell radia (for elongated cells from bacteria to giant algae cells). The physical picture is that a cell grow spherically until the preferred radius and then elongate into a cylindrical tube to keep the preferred curvature, except if a cell division occurs. A simplification of the model is investigated more quantitavely.

  20. Solar cell activation system

    SciTech Connect

    Apelian, L.

    1983-07-05

    A system for activating solar cells involves the use of phosphorescent paint, the light from which is amplified by a thin magnifying lens and used to activate solar cells. In a typical system, a member painted with phosphorescent paint is mounted adjacent a thin magnifying lens which focuses the light on a predetermined array of sensitive cells such as selenium, cadmium or silicon, mounted on a plastic board. A one-sided mirror is mounted adjacent the cells to reflect the light back onto said cells for purposes of further intensification. The cells may be coupled to rechargeable batteries or used to directly power a small radio or watch.

  1. Assessment of pancreas cells

    NASA Technical Reports Server (NTRS)

    Vanoss, C. J.

    1978-01-01

    Pancreatic islets were obtained from guinea pig pancreas by the collagenase method and kept alive in tissue culture prior to further studies. Pancreas cell morphology was studied by standard histochemical techniques using light microscopy. Preparative vertical electrophoresis-levitation of dispersed fetal guinea pig pancreas cells was conducted in phosphate buffer containing a heavy water (D20) gradient which does not cause clumping of cells or alter the osmolarity of the buffers. The faster migrating fractions tended to be enriched in beta-cell content. Alpha and delta cells were found to some degree in most fractions. A histogram showing the cell count distribution is included.

  2. Are mesenchymal stromal cells immune cells?

    PubMed

    Hoogduijn, Martin J

    2015-01-01

    Mesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities. Pre-clinical models have shown beneficial effects of MSCs in multiple immunological diseases and a number of phase 1/2 clinical trials carried out so far have reported signs of immune modulation after MSC infusion. These data indicate that MSCs play a central role in the immune response. This raises the academic question whether MSCs are immune cells or whether they are tissue precursor cells with immunoregulatory capacity. Correct understanding of the immunological properties and origin of MSCs will aid in the appropriate and safe use of the cells for clinical therapy. In this review the whole spectrum of immunological properties of MSCs is discussed with the aim of determining the position of MSCs in the immune system. PMID:25880839

  3. Germ cell binding to rat Sertoli cells in vitro

    SciTech Connect

    DePhilip, R.M.; Danahey, D.G.

    1987-12-01

    The interaction between male germ cells and Sertoli cells was studied in vitro by co-incubation experiments using isolated rat germ cells and primary cultures of Sertoli cells made germ cell-free by the differential sensitivity of germ cells to hypotonic shock. The germ cell/Sertoli cell interaction was examined morphologically with phase-contrast and scanning electron microscopy and then quantified by measuring radioactivity bound to Sertoli cell cultures after co-incubation with added (/sup 3/H)leucine-labeled germ cells. Germ cell binding to Sertoli cell cultures was the result of specific adhesion between these two cell types, and several features of this specific adhesion were observed. First, germ cells adhered to Sertoli cell cultures under conditions during which spleen cells and red blood cells did not. Second, germ cells had a greater affinity for Sertoli cell cultures than they had for cultures of testicular peritubular cells or cerebellar astrocytes. Third, germ cells fixed with paraformaldehyde adhered to live Sertoli cultures while similarly fixed spleen cells adhered less tightly. Neither live nor paraformaldehyde-fixed germ cells adhered to fixed Sertoli cell cultures. Fourth, germ cell binding to Sertoli cell cultures was not immediate but increased steadily and approached a maximum at 4 h of co-incubation. Saturation of germ cell binding to Sertoli cell cultures occurred when more than 4200 germ cells were added per mm2 of Sertoli cell culture surface. Finally, germ cell binding to Sertoli cell cultures was eliminated when co-incubation was performed on ice. Based on these observations, we concluded that germ cell adhesion to Sertoli cells was specific, temperature-dependent, and required a viable Sertoli cell but not necessarily a viable germ cell.

  4. A case of von Hippel-Lindau disease with exudative maculopathy.

    PubMed

    Ba Arah, Basel T

    2009-05-01

    Von Hippel-Lindau (VHL) disease is a rare multisystem familial tumor syndrome of autosomal dominant inheritance. Hallmark lesions include retinal, cerebellum and spinal cord hemangioblastomas, renal cell carcinomas, adrenal pheochromocytomas, angiomatous or cystic lesions of the kidneys, pancreas, and epididymis. We report a case of VHL disease in a 26-year-old patient who presented with exudative macular edema. Ocular and systemic studies revealed the presence of retinal and central nervous system hemangioblastomas, adrenal pheochromocytoma, multiple pancreatic, and kidney cysts. The retinal angiomas were successfully treated with argon laser photocoagulation and cryotherapy. PMID:20671835

  5. Single-cell growth analysis in a mixed cell culture

    NASA Astrophysics Data System (ADS)

    Ando, Jun; Bato, Mary Grace P.; Daria, Vincent Ricardo

    2008-06-01

    We perform single cell analysis of cell growth in a mixed cell culture. Two species of yeast cells: Saccharomyces cerevisiae and Candida albicans, are optically trapped using focused continuous-wave near infrared laser. Cell growth for both cells is inhibited only when the two species of cells are in contact with each other. This indicates cell-cell interaction mediated cell growth inhibition mechanism. Single cell level analysis of cell growth studied here contributes to the further understanding of yeast growth arrest in a mixed yeast culture.

  6. Mesenchymal stem cells for cardiac cell therapy.

    PubMed

    Choi, Yeong-Hoon; Kurtz, Andreas; Stamm, Christof

    2011-01-01

    Despite refinements of medical and surgical therapies, heart failure remains a fatal disease. Myocardial infarction is the most common cause of heart failure, and only palliative measures are available to relieve symptoms and prolong the patient's life span. Because mammalian cardiomyocytes irreversibly exit the cell cycle at about the time of birth, the heart has traditionally been considered to lack any regenerative capacity. This paradigm, however, is currently shifting, and the cellular composition of the myocardium is being targeted by various regeneration strategies. Adult progenitor and stem cell treatment of diseased human myocardium has been carried out for more than 10 years (Menasche et al., 2001; Stamm et al., 2003), and it has become clear that, in humans, the regenerative capacity of hematopoietic stem cells and endothelial progenitor cells, despite potent proangiogenic effects, is limited (Stamm et al., 2009). More recently, mesenchymal stem cells (MSCs) and related cell types are being evaluated in preclinical models of heart disease as well as in clinical trials (see Published Clinical Trials, below). MSCs have the capacity to self-renew and to differentiate into lineages that normally originate from the embryonic mesenchyme (connective tissues, blood vessels, blood-related organs) (Caplan, 1991; Prockop, 1997; Pittenger et al., 1999). The current definition of MSCs includes plastic adherence in cell culture, specific surface antigen expression (CD105(+)/CD90(+)/CD73(+), CD34(-)/CD45(-)/CD11b(-) or CD14(-)/CD19(-) or CD79α(-)/HLA-DR1(-)), and multilineage in vitro differentiation potential (osteogenic, chondrogenic, and adipogenic) (Dominici et al., 2006 ). If those criteria are not met completely, the term "mesenchymal stromal cells" should be used for marrow-derived adherent cells, or other terms for MSC-like cells of different origin. For the purpose of this review, MSCs and related cells are discussed in general, and cell type

  7. What Are Islet Cells?

    MedlinePlus

    ... Derived Stem Cells MichCanSka 2010 Benefits DRI Wounded Soldier Gets Standing Ovation Video New Website Launches Journal ... Derived Stem Cells MichCanSka 2010 Benefits DRI Wounded Soldier Gets Standing Ovation Video New Website Launches Journal ...

  8. Fluorescence Live Cell Imaging

    PubMed Central

    Ettinger, Andreas

    2014-01-01

    Fluorescence microscopy of live cells has become an integral part of modern cell biology. Fluorescent protein tags, live cell dyes, and other methods to fluorescently label proteins of interest provide a range of tools to investigate virtually any cellular process under the microscope. The two main experimental challenges in collecting meaningful live cell microscopy data are to minimize photodamage while retaining a useful signal-to-noise ratio, and to provide a suitable environment for cells or tissues to replicate physiological cell dynamics. This chapter aims to give a general overview on microscope design choices critical for fluorescence live cell imaging that apply to most fluorescence microscopy modalities, and on environmental control with a focus on mammalian tissue culture cells. In addition, we provide guidance on how to design and evaluate fluorescent protein constructs by spinning disk confocal microscopy. PMID:24974023

  9. Sickle Cell Trait

    MedlinePlus

    ... About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  10. Toward 'SMART' stem cells.

    PubMed

    Cheng, T

    2008-01-01

    Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically acceptable stem cells? In this editorial review, I will briefly discuss these superficially simple but actually rather complex issues that surround this fascinating cell type. The goal of this special issue on stem cells in Gene Therapy is to review some fundamental and critical aspects of current stem cell research that have translational potential. PMID:18046429

  11. Antiparietal cell antibody test

    MedlinePlus

    ... Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; Vitamin B12 - anti- ... may use this test to help diagnose pernicious anemia. Pernicious anemia is a decrease in red blood ...

  12. Cell-SELEX Technology.

    PubMed

    Ohuchi, Shoji

    2012-12-01

    Aptamers are molecules identified from large combinatorial nucleic acid libraries by their high affinity to target molecules. Due to a variety of desired properties, aptamers are attractive alternatives to antibodies in molecular biology and medical applications. Aptamers are identified through an iterative selection-amplification process known as systematic evolution of ligands by exponential enrichment (SELEX). Although SELEX is typically carried out using purified target molecules, whole live cells are also employable as selection targets. This technology, Cell-SELEX, has several advantages. For example, generated aptamers are functional with a native conformation of the target molecule on live cells, and thus, cell surface transmembrane proteins would be targets even when their purifications in native conformations are difficult. In addition, cell-specific aptamers can be obtained without any knowledge about cell surface molecules on the target cells. Here, I review the progress of Cell-SELEX technology and discuss advantages of the technology. PMID:23515081

  13. Squamous Cell Carcinoma (SCC)

    MedlinePlus

    ... A A Squamous cell carcinoma typically develops in sun-damaged skin in fair-skinned patients. Overview Squamous ... skin cancer. Squamous cell carcinoma usually occurs on sun-damaged skin, especially in light-skinned individuals with ...

  14. Sickle Cell Disease

    MedlinePlus

    ... Overview of CDC’s work. Advancements in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement ...

  15. White Blood Cell Count

    MedlinePlus

    ... Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? Also ... Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , White ...

  16. Basal Cell Carcinoma (BCC)

    MedlinePlus

    ... carcinomas: Infiltrating basal cell carcinomas can be more aggressive and locally destructive than other types of basal ... to treat them early and with slightly more aggressive techniques. Excision – The basal cell carcinoma is cut ...

  17. Giant Cell Arteritis

    MedlinePlus

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  18. Closed Small Cell Clouds

    Atmospheric Science Data Center

    2013-04-19

    article title:  Closed Small Cell Clouds in the South Pacific     ... the Multi-angle Imaging SpectroRadiometer (MISR). Closed cell clouds are formed under conditions of widespread sinking of the air above. ...

  19. Kidney Cell Electrophoresis

    NASA Technical Reports Server (NTRS)

    Todd, P.

    1985-01-01

    Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

  20. Increased voltage photovoltaic cell

    NASA Technical Reports Server (NTRS)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  1. [Hairy cell leukemia].

    PubMed

    Dietrich, S; Andrulis, M; Zenz, T

    2015-04-01

    Hairy cell leukemia was initially described as a distinct entity in 1958. It is rare B-cell malignancy characterized by an indolent course. Advances in the treatment and understanding of the biology of hairy cell leukemia have made the disease exquisitely amenable to treatment. This review summarizes the present understanding of hairy cell leukemia with a particular focus on the development of novel and targeted approaches to treatment. PMID:25787322

  2. Regenerative fuel cells

    NASA Technical Reports Server (NTRS)

    Swette, Larry L.; Kackley, Nancy D.; Laconti, Anthony B.

    1992-01-01

    A development status evaluation is presented for moderate-temperature, single-unit, regenerative fuel cells using either alkaline or solid polymer proton-exchange membrane (PEM) electrolytes. Attention is given to the results thus far obtained for Pt, Ir, Rh, and Na(x)Pt3O4 catalysts. Alkaline electrolyte tests have been performed on a half-cell basis with a floating-electrode cell; PEM testing has been with complete fuel cells, using Nafion 117.

  3. Fuel cells feasibility

    NASA Technical Reports Server (NTRS)

    Schonfeld, D.; Charng, T.

    1981-01-01

    The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.

  4. Stem Cell Research.

    PubMed

    Trounson, Alan; Kolaja, Kyle; Petersen, Thomas; Weber, Klaus; McVean, Maralee; Funk, Kathleen A

    2015-01-01

    Stem cells have great potential in basic research and are being slowly integrated into toxicological research. This symposium provided an overview of the state of the field, stem cell models, described allogenic stem cell treatments and issues of immunogenicity associated with protein therapeutics, and tehn concentrated on stem cell uses in regenerative medicine focusing on lung and testing strategies on engineered tissues from a pathologist's perspective. PMID:25899720

  5. Diagram of Cell to Cell Communication

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  6. Endothelial cells enhance migration of meniscus cells

    PubMed Central

    Yuan, Xiaoning; Eng, George M.; Arkonac, Derya E.; Chao, Pen-hsiu Grace; Vunjak-Novakovic, Gordana

    2014-01-01

    Objective To study the interactions between vascular endothelial cells and meniscal fibrochondrocytes from the inner avascular and outer vascular regions of the meniscus, and identify angiogenic factors that enhance cell migration and integrative repair. Methods Bovine meniscal fibrochondrocytes (bMFCs) from the inner and outer regions of meniscus were cultured for seven days with and without human umbilical vein endothelial cells (HUVECs) in a micropatterned three-dimensional hydrogel system for cell migration. Angiogenic factors secreted by HUVECs were probed for their role in paracrine mechanisms governing bMFC migration, and applied to a full-thickness defect model of meniscal repair in explants from the inner and outer regions over four weeks. Results Endothelial cells enhanced migration of inner and outer bMFCs in the micropatterned system via endothelin-1 (ET-1) signaling. Supplementation of ET-1 significantly enhanced integration strength of full-thickness defects in inner and outer explants, and cell migration at the macro-scale, compared to controls without ET-1 treatment. Conclusion We report for the first time that bMFCs from both the avascular and vascular regions respond to the presence of endothelial cells with increased migration. Paracrine signaling by endothelial cells regulates the bMFCs differentially by region, but we identify ET-1 as an angiogenic factor that stimulates migration of inner and outer cells at the micro-scale, and integrative repair of inner and outer explants at the macro-scale. These findings reveal the regional interactions between vasculature and MFCs, and suggest ET-1 as a potential new treatment modality for avascular meniscal injuries, in order to prevent the development of osteoarthritis. PMID:25307081

  7. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    PubMed Central

    Gross, Christine; Thoma-Kress, Andrea K.

    2016-01-01

    The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1), a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1) polarized budding of HTLV-1 into synaptic clefts; and (2) cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation. PMID:27005656

  8. Cell phones and cancer

    MedlinePlus

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of exposure ...

  9. Biomarkers of cell senescence

    DOEpatents

    Dimri, G.P.; Campisi, J.; Peacocke, M.

    1998-08-18

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, {beta}-galactosidase activity is utilized as a means by which cell senescence may be assessed either in vitro cell cultures or in vivo. 1 fig.

  10. Biomarkers of cell senescence

    DOEpatents

    Dirmi, G.P.; Campisi, J.; Peacocke, M.

    1996-02-13

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, {beta}-galactosidase activity is utilized as a means by which cell senescence may be assessed either in in vitro cell cultures or in vivo. 1 fig.

  11. Mammalian Cell Culture Simplified.

    ERIC Educational Resources Information Center

    Moss, Robert; Solomon, Sondra

    1991-01-01

    A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

  12. Plasma Cell Disorders

    MedlinePlus

    ... microorganisms to which the body is exposed. In plasma cell disorders, one clone of plasma cells multiplies uncontrollably. As a result, this clone ... a light chain and heavy chain). These abnormal plasma cells and the ... produce are limited to one type, and levels of other types of antibodies ...

  13. Solar Photovoltaic Cells.

    ERIC Educational Resources Information Center

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  14. Pancreas Cell Fate

    PubMed Central

    Guney, Michelle A.; Gannon, Maureen

    2009-01-01

    Diabetes is characterized by decreased function of insulin-producing insulin β cells and insufficient insulin output resulting from an absolute (Type 1) or relative (Type 2) inadequate functional β cell mass. Both forms of the disease would greatly benefit from treatment strategies that could enhance β cell regeneration and/or function. Successful and reliable methods of generatingβ cells or whole islets from progenitor cells in vivo or in vitro could lead to restoration of β cell mass in individuals with Type 1 diabetes and enhanced β cell compensation in Type 2 patients. A thorough understanding of the normal developmental processes that occur during pancreatic organogenesis, e.g., transcription factors, cell signaling molecules, and cell-cell interactions that regulate endocrine differentiation from the embryonic pancreatic epithelium, is required in order to successfully reach these goals. This review summarizes our current understanding of pancreas development, with particular emphasis on factors intrinsic or extrinsic to the pancreatic epithelium that are involved in regulating the development and differentiation of the various pancreatic cell types. We also discuss the recent progress in generating insulin-producing cells from progenitor sources. PMID:19750517

  15. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  16. Photoelectrochemical Solar Cells.

    ERIC Educational Resources Information Center

    McDevitt, John T.

    1984-01-01

    This introduction to photoelectrochemical (PEC) cells reviews topics pertaining to solar energy conversion and demonstrates the ease with which a working PEC cell can be prepared with n-type silicon as the photoanode and a platinum counter electrode (both immersed in ethanolic ferrocene/ferricenium solutions). Experiments using the cell are…

  17. Solar cell device

    SciTech Connect

    Nishiura, M.; Haruki, H.; Miyagi, M.; Sakai, H.; Uchida, Y.

    1984-06-26

    A solar cell array is equipped with serially or parallel connected reverse polarity diodes formed simultaneously with the array. The diodes are constituted by one or more solar cells of the array which may be shaded to prevent photoelectric conversion, and which are electrically connected in reverse polarity with respect to the remaining cells.

  18. Biomarkers of cell senescence

    DOEpatents

    Dirmi, Goberdhan P.; Campisi, Judith; Peacocke, Monica

    1996-01-01

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, .beta.-galactosidase activity is utilized as a means by which cell senescence may be assessed either in in vitro cell cultures or in vivo.

  19. Biomarkers of cell senescence

    DOEpatents

    Dimri, Goberdhan P.; Campisi, Judith; Peacocke, Monica

    1998-01-01

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, .beta.-galactosidase activity is utilized as a means by which cell senescence may be assessed either in vitro cell cultures or in vivo.

  20. Cell Culture Made Easy.

    ERIC Educational Resources Information Center

    Dye, Frank J.

    1985-01-01

    Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

  1. Mast cells and inflammation.

    PubMed

    Theoharides, Theoharis C; Alysandratos, Konstantinos-Dionysios; Angelidou, Asimenia; Delivanis, Danae-Anastasia; Sismanopoulos, Nikolaos; Zhang, Bodi; Asadi, Shahrzad; Vasiadi, Magdalini; Weng, Zuyi; Miniati, Alexandra; Kalogeromitros, Dimitrios

    2012-01-01

    Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33 and neurotensin. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. This article is part of a Special Issue entitled: Mast cells in inflammation. PMID:21185371

  2. Cell phones and cancer

    MedlinePlus

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  3. Adventures with Cell Phones

    ERIC Educational Resources Information Center

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  4. Stochastic elimination of cancer cells.

    PubMed Central

    Michor, Franziska; Nowak, Martin A; Frank, Steven A; Iwasa, Yoh

    2003-01-01

    Tissues of multicellular organisms consist of stem cells and differentiated cells. Stem cells divide to produce new stem cells or differentiated cells. Differentiated cells divide to produce new differentiated cells. We show that such a tissue design can reduce the rate of fixation of mutations that increase the net proliferation rate of cells. It has, however, no consequence for the rate of fixation of neutral mutations. We calculate the optimum relative abundance of stem cells that minimizes the rate of generating cancer cells. There is a critical fraction of stem cell divisions that is required for a stochastic elimination ('wash out') of cancer cells. PMID:14561289

  5. Microfluidic fuel cells

    NASA Astrophysics Data System (ADS)

    Kjeang, Erik

    Microfluidic fuel cell architectures are presented in this thesis. This work represents the mechanical and microfluidic portion of a microfluidic biofuel cell project. While the microfluidic fuel cells developed here are targeted to eventual integration with biocatalysts, the contributions of this thesis have more general applicability. The cell architectures are developed and evaluated based on conventional non-biological electrocatalysts. The fuel cells employ co-laminar flow of fuel and oxidant streams that do not require a membrane for physical separation, and comprise carbon or gold electrodes compatible with most enzyme immobilization schemes developed to date. The demonstrated microfluidic fuel cell architectures include the following: a single cell with planar gold electrodes and a grooved channel architecture that accommodates gaseous product evolution while preventing crossover effects; a single cell with planar carbon electrodes based on graphite rods; a three-dimensional hexagonal array cell based on multiple graphite rod electrodes with unique scale-up opportunities; a single cell with porous carbon electrodes that provides enhanced power output mainly attributed to the increased active area; a single cell with flow-through porous carbon electrodes that provides improved performance and overall energy conversion efficiency; and a single cell with flow-through porous gold electrodes with similar capabilities and reduced ohmic resistance. As compared to previous results, the microfluidic fuel cells developed in this work show improved fuel cell performance (both in terms of power density and efficiency). In addition, this dissertation includes the development of an integrated electrochemical velocimetry approach for microfluidic devices, and a computational modeling study of strategic enzyme patterning for microfluidic biofuel cells with consecutive reactions.

  6. Cell adhesion molecules involved in intrathymic T cell development.

    PubMed

    Patel, D D; Haynes, B F

    1993-08-01

    During stem cell migration to the thymus, intrathymic maturation of T cells, and emigration of mature T cells out of the thymus, intercellular interactions of developing T cells with a myriad of cell types are required for normal T cell development. Intercellular interactions of T cell precursors with endothelial cells, thymic epithelial cells, fibroblasts, thymic macrophages and dendritic cells are all mediated by adhesion molecules on immature T cells binding to ligands on thymic microenvironment cells. While many receptor-ligand interactions that are important in intrathymic T cell development are known, the adhesion molecules that are important for migration of T cell precursors to the thymus and for emigration of mature thymocytes from the thymus are poorly understood. An emerging concept is that select adhesion molecules at discrete stages of T cell maturation participate in and regulate the complex processes of T cell development. PMID:7693023

  7. Regulation of Th2 Cell Immunity by Dendritic Cells

    PubMed Central

    Na, Hyeongjin

    2016-01-01

    Th2 cell immunity is required for host defense against helminths, but it is detrimental in allergic diseases in humans. Unlike Th1 cell and Th17 cell subsets, the mechanism by which dendritic cells modulate Th2 cell responses has been obscure, in part because of the inability of dendritic cells to provide IL-4, which is indispensable for Th2 cell lineage commitment. In this regard, immune cells other than dendritic cells, such as basophils and innate lymphoid cells, have been suggested as Th2 cell inducers. More recently, multiple independent researchers have shown that specialized subsets of dendritic cells mediate Th2 cell responses. This review will discuss the current understanding related to the regulation of Th2 cell responses by dendritic cells and other immune cells. PMID:26937227

  8. Leukemia - B-Cell Prolymphocytic Leukemia and Hairy Cell Leukemia

    MedlinePlus

    ... Leukemia: Introduction Request Permissions Print to PDF Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia: Introduction ... Research and Advocacy Survivorship Blog About Us Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia Guide ...

  9. Fuel Cell Handbook update

    SciTech Connect

    Owens, W.R.; Hirschenhofer, J.H.; Engleman, R.R. Jr.; Stauffer, D.B.

    1993-11-01

    The objective of this work was to update the 1988 version of DOE`s Fuel Cell Handbook. Significant developments in the various fuel cell technologies required revisions to reflect state-of-the-art configurations and performance. The theoretical presentation was refined in order to make the handbook more useful to both the casual reader and fuel cell or systems analyst. In order to further emphasize the practical application of fuel cell technologies, the system integration information was expanded. In addition, practical elements, such as suggestions and guidelines to approximate fuel cell performance, were provided.

  10. Skeletal muscle satellite cells

    NASA Technical Reports Server (NTRS)

    Schultz, E.; McCormick, K. M.

    1994-01-01

    Evidence now suggests that satellite cells constitute a class of myogenic cells that differ distinctly from other embryonic myoblasts. Satellite cells arise from somites and first appear as a distinct myoblast type well before birth. Satellite cells from different muscles cannot be functionally distinguished from one another and are able to provide nuclei to all fibers without regard to phenotype. Thus, it is difficult to ascribe any significant function to establishing or stabilizing fiber type, even during regeneration. Within a muscle, satellite cells exhibit marked heterogeneity with respect to their proliferative behavior. The satellite cell population on a fiber can be partitioned into those that function as stem cells and those which are readily available for fusion. Recent studies have shown that the cells are not simply spindle shaped, but are very diverse in their morphology and have multiple branches emanating from the poles of the cells. This finding is consistent with other studies indicating that the cells have the capacity for extensive migration within, and perhaps between, muscles. Complexity of cell shape usually reflects increased cytoplasmic volume and organelles including a well developed Golgi, and is usually associated with growing postnatal muscle or muscles undergoing some form of induced adaptive change or repair. The appearance of activated satellite cells suggests some function of the cells in the adaptive process through elaboration and secretion of a product. Significant advances have been made in determining the potential secretion products that satellite cells make. The manner in which satellite cell proliferative and fusion behavior is controlled has also been studied. There seems to be little doubt that cellcell coupling is not how satellite cells and myofibers communicate. Rather satellite cell regulation is through a number of potential growth factors that arise from a number of sources. Critical to the understanding of this form

  11. Making Ultrathin Solar Cells

    NASA Technical Reports Server (NTRS)

    Cogan, George W.; Christel, Lee A.; Merchant, J. Thomas; Gibbons, James F.

    1991-01-01

    Process produces extremely thin silicon solar cells - only 50 micrometers or less in thickness. Electrons and holes have less opportunity to recombine before collected at cell surfaces. Efficiency higher and because volume of silicon small, less chance of radiation damage in new cells. Initial steps carried out at normal thickness to reduce breakage and avoid extra cost of special handling. Cells then thinned mechanically and chemically. Final cell includes reflective layer on back surface. Layer bounces unabsorbed light back into bulk silicon so it absorbs and produces useful electrical output.

  12. Transparent ultraviolet photovoltaic cells.

    PubMed

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future. PMID:26872163

  13. Fuel Cell Handbook update

    NASA Astrophysics Data System (ADS)

    Owens, W. R.; Hirschenhofer, J. H.; Engleman, R. R., Jr.; Stauffer, D. B.

    The objective of this work was to update the 1988 version of DOE's Fuel Cell Handbook. Significant developments in the various fuel cell technologies required revisions to reflect state-of-the-art configurations and performance. The theoretical presentation was refined in order to make the handbook more useful to both the casual reader and fuel cell or systems analyst. In order to further emphasize the practical application of fuel cell technologies, the system integration information was expanded. In addition, practical elements, such as suggestions and guidelines to approximate fuel cell performance, were provided.

  14. Place Cells, Grid Cells, Attractors, and Remapping

    PubMed Central

    Jeffery, Kathryn J.

    2011-01-01

    Place and grid cells are thought to use a mixture of external sensory information and internal attractor dynamics to organize their activity. Attractor dynamics may explain both why neurons react coherently following sufficiently large changes to the environment (discrete attractors) and how firing patterns move smoothly from one representation to the next as an animal moves through space (continuous attractors). However, some features of place cell behavior, such as the sometimes independent responsiveness of place cells to environmental change (called “remapping”), seem hard to reconcile with attractor dynamics. This paper suggests that the explanation may be found in an anatomical separation of the two attractor systems coupled with a dynamic contextual modulation of the connection matrix between the two systems, with new learning being back-propagated into the matrix. Such a scheme could explain how place cells sometimes behave coherently and sometimes independently. PMID:22135756

  15. Fuel Cell/Electrochemical Cell Voltage Monitor

    NASA Technical Reports Server (NTRS)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  16. Mast cells and inflammation

    PubMed Central

    Theoharides, Theoharis C.; Alysandratos, Konstantinos-Dionysios; Angelidou, Asimenia; Delivanis, Danae-Anastasia; Sismanopoulos, Nikolaos; Zhang, Bodi; Asadi, Shahrzad; Vasiadi, Magdalini; Weng, Zuyi; Miniati, Alexandra; Kalogeromitros, Dimitrios

    2012-01-01

    Mast cells are well known for their role in allergic and anaphylactic reactions, as well as their involvement in acquired and innate immunity. Increasing evidence now implicates mast cells in inflammatory diseases where they are activated by non-allergic triggers, such as neuropeptides and cytokines, often exerting synergistic effects as in the case of IL-33. Mast cells can also release pro-inflammatory mediators selectively without degranulation. In particular, IL-1 induces selective release of IL-6, while corticotropin-releasing hormone secreted under stress induces the release of vascular endothelial growth factor. Many inflammatory diseases involve mast cells in cross-talk with T cells, such as atopic dermatitis, psoriasis and multiple sclerosis, which all worsen by stress. How mast cell differential responses are regulated is still unresolved. Preliminary evidence suggests that mitochondrial function and dynamics control mast cell degranulation, but not selective release. Recent findings also indicate that mast cells have immunomodulatory properties. Understanding selective release of mediators could explain how mast cells participate in numerous diverse biologic processes, and how they exert both immunostimulatory and immunosuppressive actions. Unraveling selective mast cell secretion could also help develop unique mast cell inhibitors with novel therapeutic applications. PMID:21185371

  17. Parameterization of solar cells

    NASA Astrophysics Data System (ADS)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-10-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  18. Electroporation of cell membranes.

    PubMed

    Tsong, T Y

    1991-08-01

    Electric pulses of intensity in kilovolts per centimeter and of duration in microseconds to milliseconds cause a temporary loss of the semipermeability of cell membranes, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. A generally accepted term describing this phenomenon is "electroporation." Other effects of a high-intensity electric field on cell membranes include membrane fusions, bleb formation, cell lysis... etc. Electroporation and its related phenomena reflect the basic bioelectrochemistry of cell membranes and are thus important for the study of membrane structure and function. These phenomena also occur in such events as electric injury, electrocution, and cardiac procedures involving electric shocks. Electroporation has found applications in: (a) introduction of plasmids or foreign DNA into living cells for gene transfections, (b) fusion of cells to prepare heterokaryons, hybridoma, hybrid embryos... etc., (c) insertion of proteins into cell membranes, (d) improving drug delivery and hence effectiveness in chemotherapy of cancerous cells, (e) constructing animal model by fusing human cells with animal tissues, (f) activation of membrane transporters and enzymes, and (g) alteration of genetic expression in living cells. A brief review of mechanistic studies of electroporation is given. PMID:1912274

  19. Electroporation of cell membranes.

    PubMed Central

    Tsong, T Y

    1991-01-01

    Electric pulses of intensity in kilovolts per centimeter and of duration in microseconds to milliseconds cause a temporary loss of the semipermeability of cell membranes, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. A generally accepted term describing this phenomenon is "electroporation." Other effects of a high-intensity electric field on cell membranes include membrane fusions, bleb formation, cell lysis... etc. Electroporation and its related phenomena reflect the basic bioelectrochemistry of cell membranes and are thus important for the study of membrane structure and function. These phenomena also occur in such events as electric injury, electrocution, and cardiac procedures involving electric shocks. Electroporation has found applications in: (a) introduction of plasmids or foreign DNA into living cells for gene transfections, (b) fusion of cells to prepare heterokaryons, hybridoma, hybrid embryos... etc., (c) insertion of proteins into cell membranes, (d) improving drug delivery and hence effectiveness in chemotherapy of cancerous cells, (e) constructing animal model by fusing human cells with animal tissues, (f) activation of membrane transporters and enzymes, and (g) alteration of genetic expression in living cells. A brief review of mechanistic studies of electroporation is given. PMID:1912274

  20. Stress and stem cells.

    PubMed

    Tower, John

    2012-01-01

    The unique properties and functions of stem cells make them particularly susceptible to stresses and also lead to their regulation by stress. Stem cell division must respond to the demand to replenish cells during normal tissue turnover as well as in response to damage. Oxidative stress, mechanical stress, growth factors, and cytokines signal stem cell division and differentiation. Many of the conserved pathways regulating stem cell self-renewal and differentiation are also stress-response pathways. The long life span and division potential of stem cells create a propensity for transformation (cancer) and specific stress responses such as apoptosis and senescence act as antitumor mechanisms. Quiescence regulated by CDK inhibitors and a hypoxic niche regulated by FOXO transcription factor function to reduce stress for several types of stem cells to facilitate long-term maintenance. Aging is a particularly relevant stress for stem cells, because repeated demands on stem cell function over the life span can have cumulative cell-autonomous effects including epigenetic dysregulation, mutations, and telomere erosion. In addition, aging of the organism impairs function of the stem cell niche and systemic signals, including chronic inflammation and oxidative stress. PMID:23799624

  1. Follicular Helper T Cells.

    PubMed

    Vinuesa, Carola G; Linterman, Michelle A; Yu, Di; MacLennan, Ian C M

    2016-05-20

    Although T cell help for B cells was described several decades ago, it was the identification of CXCR5 expression by B follicular helper T (Tfh) cells and the subsequent discovery of their dependence on BCL6 that led to the recognition of Tfh cells as an independent helper subset and accelerated the pace of discovery. More than 20 transcription factors, together with RNA-binding proteins and microRNAs, control the expression of chemotactic receptors and molecules important for the function and homeostasis of Tfh cells. Tfh cells prime B cells to initiate extrafollicular and germinal center antibody responses and are crucial for affinity maturation and maintenance of humoral memory. In addition to the roles that Tfh cells have in antimicrobial defense, in cancer, and as HIV reservoirs, regulation of these cells is critical to prevent autoimmunity. The realization that follicular T cells are heterogeneous, comprising helper and regulatory subsets, has raised questions regarding a possible division of labor in germinal center B cell selection and elimination. PMID:26907215

  2. Parameterization of solar cells

    NASA Technical Reports Server (NTRS)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-01-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  3. T cell subpopulations.

    PubMed

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  4. Protrusive Activity Guides Changes in Cell-Cell Tension during Epithelial Cell Scattering

    PubMed Central

    Maruthamuthu, Venkat; Gardel, Margaret L.

    2014-01-01

    Knowing how epithelial cells regulate cell-matrix and cell-cell adhesions is essential to understand key events in morphogenesis as well as pathological events such as metastasis. During epithelial cell scattering, epithelial cell islands rupture their cell-cell contacts and migrate away as single cells on the extracellular matrix (ECM) within hours of growth factor stimulation, even as adhesion molecules such as E-cadherin are present at the cell-cell contact. How the stability of cell-cell contacts is modulated to effect such morphological transitions is still unclear. Here, we report that in the absence of ECM, E-cadherin adhesions continue to sustain substantial cell-generated forces upon hepatocyte growth factor (HGF) stimulation, consistent with undiminished adhesion strength. In the presence of focal adhesions, constraints that preclude the spreading and movement of cells at free island edges also prevent HGF-mediated contact rupture. To explore the role of cell motion and cell-cell contact rupture, we examine the biophysical changes that occur during the scattering of cell pairs. We show that the direction of cell movement with respect to the cell-cell contact is correlated with changes in the average intercellular force as well as the initial direction of cell-cell contact rupture. Our results suggest an important role for protrusive activity resulting in cell displacement and force redistribution in guiding cell-cell contact rupture during scattering. PMID:25099795

  5. T Cells Going Innate.

    PubMed

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  6. Microbial sensor cell arrays.

    PubMed

    Melamed, Sahar; Elad, Tal; Belkin, Shimshon

    2012-02-01

    Motivated by the advantages endowed by high-throughput analysis, researchers have succeeded in incorporating multiple reporter cells into a single platform; the technology now allows the simultaneous scrutiny of a large collection of sensor strains. We review current aspects in cell array technology with emphasis on microbial sensor arrays. We consider various techniques for patterning live cells on solid surfaces, describe different array-based applications and devices, and highlight recent efforts for live cell storage. We review mathematical approaches for deciphering the data emanating from bioreporter collections, and discuss the future of single cell arrays. Innovative technologies for cell patterning, preservation and interpretation are continuously being developed; when they all mature, cell arrays may become an efficient analytical tool, in a scope resembling that of DNA microarray biochips. PMID:22176747

  7. Cell Differentiation and Checkpoint

    PubMed Central

    Sancho, Sara Cuesta; Ouchi, Toru

    2015-01-01

    DNA damage is induced in many types of cells by internal and external cell stress. When DNA is damaged, DNA Damage Response (DDR) programs are activated to repair the DNA lesions in order to preserve genomic integrity and suppress subsequent malignant transformation. Among these programs is cell cycle checkpoint that ensures cell cycle arrest and subsequent repair of the damaged DNA, apoptosis and senescence in various phases of the cell cycle. Moreover, recent studies have established the cell differentiation checkpoint, the other type of the checkpoint that is specifically activated in the course of differentiation. We will discuss the evidences that support the link between DNA damage proteins and C2C12 cell differentiation. PMID:26998525

  8. Cell sorting apparatus

    NASA Technical Reports Server (NTRS)

    Yen, Shiao-Ping S. (Inventor); Rembaum, Alan (Inventor); Molday, Robert S. (Inventor)

    1980-01-01

    Polymeric functional microspheres containing metal or metal compounds are formed by addition polymerization of a covalently bondable olefinic monomer such as hydroxyethylmethacrylate in the presence of finely divided metal or metal oxide particles, such as iron, gold, platinum or magnetite, which are embedded in the resulting microspheres. The microspheres can be covalently bonded to chemotherapeutic agents, antibodies, or other proteins providing a means for labeling or separating labeled cells. Labeled cells or microspheres can be concentrated at a specific body location such as in the vicinity of a malignant tumor by applying a magnetic field to the location and then introducing the magnetically attractable microspheres or cells into the circulatory system of the subject. Labeled cells can be separated from a cell mixture by applying a predetermined magnetic field to a tube in which the mixture is flowing. After collection of the labeled cells, the magnetic field is discontinued and the labeled sub-cell population recovered.

  9. Intraoperative Stem Cell Therapy

    PubMed Central

    Coelho, Mónica Beato; Cabral, Joaquim M.S.; Karp, Jeffrey M.

    2013-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the potential regenerative mechanisms and the roles of different cell populations in the regeneration process are discussed. Although intraoperative stem cell therapies have been shown to be safe and effective for several indications, there are still critical challenges to be tackled prior to adoption into the standard surgical armamentarium. PMID:22809140

  10. Natural killer cell deficiency

    PubMed Central

    Orange, Jordan S.

    2013-01-01

    Natural killer (NK) cells are part of the innate immune defense against infection and cancer, and are especially useful in combating certain viral pathogens. The utility of NK cells in human health has been underscored by a growing number of individuals who are deficient in NK cells and/or their functions. This can be in the context of a broader genetically-defined congenital immunodeficiency of which there are over forty presently known to impair NK cells. The abnormality of NK cells, however, in certain cases represents the majority immunological defect. In aggregate, these conditions are termed NK cell deficiency. Recent advances have added clarity to this diagnosis and identified defects in three different genes that can cause NK cell deficiency as well as some of the underlying biology. Appropriate consideration of these diagnoses and patients raises the potential for rational therapeutic options and further innovation. PMID:23993353

  11. Cell wall integrity

    PubMed Central

    Pogorelko, Gennady; Lionetti, Vincenzo; Bellincampi, Daniela; Zabotina, Olga

    2013-01-01

    The plant cell wall, a dynamic network of polysaccharides and glycoproteins of significant compositional and structural complexity, functions in plant growth, development and stress responses. In recent years, the existence of plant cell wall integrity (CWI) maintenance mechanisms has been demonstrated, but little is known about the signaling pathways involved, or their components. Examination of key mutants has shed light on the relationships between cell wall remodeling and plant cell responses, indicating a central role for the regulatory network that monitors and controls cell wall performance and integrity. In this review, we present a short overview of cell wall composition and discuss post-synthetic cell wall modification as a valuable approach for studying CWI perception and signaling pathways. PMID:23857352

  12. Tuning cell fate

    PubMed Central

    Kami, Daisuke; Gojo, Satoshi

    2014-01-01

    Epigenetic interventions are required to induce reprogramming from one cell type to another. At present, various cellular reprogramming methods such as somatic cell nuclear transfer, cell fusion, and direct reprogramming using transcription factors have been reported. In particular, direct reprogramming from somatic cells to induced pluripotent stem cells (iPSCs) has been achieved using defined factors that play important epigenetic roles. Although the mechanisms underlying cellular reprogramming and vertebrate regeneration, including appendage regeneration, remain unknown, dedifferentiation occurs at an early phase in both the events, and both events are contrasting with regard to cell death. We compared the current status of changes in cell fate of iPSCs with that of vertebrate regeneration and suggested that substantial insights into vertebrate regeneration should be helpful for safe applications of iPSCs to medicine. PMID:24736602

  13. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation

    PubMed Central

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells) are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation. PMID:26635851

  14. Sickle Cell Crisis (Pain Crisis)

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Sickle Cell Crisis (Pain Crisis) KidsHealth > For Teens > Sickle Cell ... A A A Text Size What Is a Sickle Cell Crisis? Sickle cell disease changes the shape of ...

  15. Membrane Cells for Brine Electrolysis.

    ERIC Educational Resources Information Center

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  16. Information on Stem Cell Research

    MedlinePlus

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  17. Nestin(+) cells direct inflammatory cell migration in atherosclerosis.

    PubMed

    Del Toro, Raquel; Chèvre, Raphael; Rodríguez, Cristina; Ordóñez, Antonio; Martínez-González, José; Andrés, Vicente; Méndez-Ferrer, Simón

    2016-01-01

    Atherosclerosis is a leading death cause. Endothelial and smooth muscle cells participate in atherogenesis, but it is unclear whether other mesenchymal cells contribute to this process. Bone marrow (BM) nestin(+) cells cooperate with endothelial cells in directing monocyte egress to bloodstream in response to infections. However, it remains unknown whether nestin(+) cells regulate inflammatory cells in chronic inflammatory diseases, such as atherosclerosis. Here, we show that nestin(+) cells direct inflammatory cell migration during chronic inflammation. In Apolipoprotein E (ApoE) knockout mice fed with high-fat diet, BM nestin(+) cells regulate the egress of inflammatory monocytes and neutrophils. In the aorta, nestin(+) stromal cells increase ∼30 times and contribute to the atheroma plaque. Mcp1 deletion in nestin(+) cells-but not in endothelial cells only- increases circulating inflammatory cells, but decreases their aortic infiltration, delaying atheroma plaque formation and aortic valve calcification. Therefore, nestin expression marks cells that regulate inflammatory cell migration during atherosclerosis. PMID:27586429

  18. Functional interplay between the cell cycle and cell phenotypes.

    PubMed

    Chen, Wei-Chiang; Wu, Pei-Hsun; Phillip, Jude M; Khatau, Shyam B; Choi, Jae Min; Dallas, Matthew R; Konstantopoulos, Konstantinos; Sun, Sean X; Lee, Jerry S H; Hodzic, Didier; Wirtz, Denis

    2013-03-01

    Cell cycle distribution of adherent cells is typically assessed using flow cytometry, which precludes the measurements of many cell properties and their cycle phase in the same environment. Here we develop and validate a microscopy system to quantitatively analyze the cell-cycle phase of thousands of adherent cells and their associated cell properties simultaneously. This assay demonstrates that population-averaged cell phenotypes can be written as a linear combination of cell-cycle fractions and phase-dependent phenotypes. By perturbing the cell cycle through inhibition of cell-cycle regulators or changing nuclear morphology by depletion of structural proteins, our results reveal that cell cycle regulators and structural proteins can significantly interfere with each other's prima facie functions. This study introduces a high-throughput method to simultaneously measure the cell cycle and phenotypes at single-cell resolution, which reveals a complex functional interplay between the cell cycle and cell phenotypes. PMID:23319145

  19. Fragmentation of cancer cells

    NASA Astrophysics Data System (ADS)

    Vanapalli, Siva; Kamyabi, Nabiollah

    Tumor cells have to travel through blood capillaries to be able to metastasize and colonize in distant organs. Among the numerous cells that are shed by the primary tumor, very few survive in circulation. In vivo studies have shown that tumor cells can undergo breakup at microcapillary junctions affecting their survival. It is currently unclear what hydrodynamic and biomechanical factors contribute to fragmentation and moreover how different are the breakup dynamics of highly and weakly metastatic cells. In this study, we use microfluidics to investigate flow-induced breakup of prostate and breast cancer cells. We observe several different modes of breakup of cancer cells, which have striking similarities with breakup of viscous drops. We quantify the breakup time and find that highly metastatic cancer cells take longer to breakup than lowly metastatic cells suggesting that tumor cells may dynamically modify their deformability to avoid fragmentation. We also identify the role that cytoskeleton and membrane plays in the breakup process. Our study highlights the important role that tumor cell fragmentation plays in cancer metastasis. Cancer Prevention and Research Institute of Texas.

  20. T Cells in Fish

    PubMed Central

    Nakanishi, Teruyuki; Shibasaki, Yasuhiro; Matsuura, Yuta

    2015-01-01

    Cartilaginous and bony fish are the most primitive vertebrates with a thymus, and possess T cells equivalent to those in mammals. There are a number of studies in fish demonstrating that the thymus is the essential organ for development of T lymphocytes from early thymocyte progenitors to functionally competent T cells. A high number of T cells in the intestine and gills has been reported in several fish species. Involvement of CD4+ and CD8α+ T cells in allograft rejection and graft-versus-host reaction (GVHR) has been demonstrated using monoclonal antibodies. Conservation of CD4+ helper T cell functions among teleost fishes has been suggested in a number studies employing mixed leukocyte culture (MLC) and hapten/carrier effect. Alloantigen- and virus-specific cytotoxicity has also been demonstrated in ginbuna and rainbow trout. Furthermore, the important role of cell-mediated immunity rather than humoral immunity has been reported in the protection against intracellular bacterial infection. Recently, the direct antibacterial activity of CD8α+, CD4+ T-cells and sIgM+ cells in fish has been reported. In this review, we summarize the recent progress in T cell research focusing on the tissue distribution and function of fish T cells. PMID:26426066

  1. Brain tumor stem cells.

    PubMed

    Palm, Thomas; Schwamborn, Jens C

    2010-06-01

    Since the end of the 'no-new-neuron' theory, emerging evidence from multiple studies has supported the existence of stem cells in neurogenic areas of the adult brain. Along with this discovery, neural stem cells became candidate cells being at the origin of brain tumors. In fact, it has been demonstrated that molecular mechanisms controlling self-renewal and differentiation are shared between brain tumor stem cells and neural stem cells and that corruption of genes implicated in these pathways can direct tumor growth. In this regard, future anticancer approaches could be inspired by uncovering such redundancies and setting up treatments leading to exhaustion of the cancer stem cell pool. However, deleterious effects on (normal) neural stem cells should be minimized. Such therapeutic models underline the importance to study the cellular mechanisms implicated in fate decisions of neural stem cells and the oncogenic derivation of adult brain cells. In this review, we discuss the putative origins of brain tumor stem cells and their possible implications on future therapies. PMID:20370314

  2. Simple Cell Balance Circuit

    NASA Technical Reports Server (NTRS)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  3. The leukemic stem cell

    PubMed Central

    Jordan, Craig T.

    2007-01-01

    Malignant stem cells have recently been described as the source of several types of human cancer. These unique cell types are typically rare and possess properties that are distinct from most other tumor cells. The properties of leukemic stem cells indicate that current chemotherapy drugs will not be effective. The use of current cytotoxic agents is not effective in leukemia because the agents target both the leukemic and normal stem cell populations. Consequently, new strategies are required that specifically and preferentially target the malignant stem cell population, while sparing normal stem cells. Several well known agents are lethal for the leukemic stem cell in preclinical testing. They include parthenolide, commonly known as feverfew, and TDZD-8. They have undergone various levels of preclinical development, but have not been used in patients as yet in the cancer setting. These drugs and combinations of existing therapies that target the leukemic stem cell population may provide a cure in this disease. This article summarizes recent findings in the leukemic stem cell field and discusses new directions for therapy. PMID:17336250

  4. Stem Cell Separation Technologies

    PubMed Central

    Zhu, Beili; Murthy, Shashi K.

    2012-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell sorting (FACS), Magnet-activated cell sorting (MACS), pre-plating, conditioned expansion media, density gradient centrifugation, field flow fractionation (FFF), and dielectrophoresis (DEP). Next, we will introduce emerging novel methods that are currently under development. These methods include improved aqueous two-phase system, systematic evolution of ligands by exponential enrichment (SELEX), and various types of microfluidic platforms. Finally, we will discuss the challenges and directions towards future breakthroughs for stem cell isolation. Advancing stem cell separation techniques will be essential for clinical and research applications of stem cells. PMID:23505616

  5. T follicular regulatory cells.

    PubMed

    Sage, Peter T; Sharpe, Arlene H

    2016-05-01

    Pathogen exposure elicits production of high-affinity antibodies stimulated by T follicular helper (Tfh) cells in the germinal center reaction. Tfh cells provide both costimulation and stimulatory cytokines to B cells to facilitate affinity maturation, class switch recombination, and plasma cell differentiation within the germinal center. Under normal circumstances, the germinal center reaction results in antibodies that precisely target foreign pathogens while limiting autoimmunity and excessive inflammation. In order to have this degree of control, the immune system ensures Tfh-mediated B-cell help is regulated locally in the germinal center. The recently identified T follicular regulatory (Tfr) cell subset can migrate to the germinal center and inhibit Tfh-mediated B-cell activation and antibody production. Although many aspects of Tfr cell biology are still unclear, recent data have begun to delineate the specialized roles of Tfr cells in controlling the germinal center reaction. Here we discuss the current understanding of Tfr-cell differentiation and function and how this knowledge is providing new insights into the dynamic regulation of germinal centers, and suggesting more efficacious vaccine strategies and ways to treat antibody-mediated diseases. PMID:27088919

  6. Epithelial Cell Adhesion Molecule

    PubMed Central

    Trzpis, Monika; McLaughlin, Pamela M.J.; de Leij, Lou M.F.H.; Harmsen, Martin C.

    2007-01-01

    The epithelial cell adhesion molecule (EpCAM, CD326) is a glycoprotein of ∼40 kd that was originally identified as a marker for carcinoma, attributable to its high expression on rapidly proliferating tumors of epithelial origin. Normal epithelia express EpCAM at a variable but generally lower level than carcinoma cells. In early studies, EpCAM was proposed to be a cell-cell adhesion molecule. However, recent insights revealed a more versatile role for EpCAM that is not limited only to cell adhesion but includes diverse processes such as signaling, cell migration, proliferation, and differentiation. Cell surface expression of EpCAM may actually prevent cell-cell adhesion. Here, we provide a comprehensive review of the current knowledge on EpCAM biology in relation to other cell adhesion molecules. We discuss the implications of the newly identified functions of EpCAM in view of its prognostic relevance in carcinoma, inflammatory pathophysiology, and tissue development and regeneration as well as its role in normal epithelial homeostasis. PMID:17600130

  7. Single cell wound repair

    PubMed Central

    Abreu-Blanco, Maria Teresa; Verboon, Jeffrey M

    2011-01-01

    Cell wounding is a common event in the life of many cell types, and the capacity of the cell to repair day-to-day wear-and-tear injuries, as well as traumatic ones, is fundamental for maintaining tissue integrity. Cell wounding is most frequent in tissues exposed to high levels of stress. Survival of such plasma membrane disruptions requires rapid resealing to prevent the loss of cytosolic components, to block Ca2+ influx and to avoid cell death. In addition to patching the torn membrane, plasma membrane and cortical cytoskeleton remodeling are required to restore cell function. Although a general understanding of the cell wound repair process is in place, the underlying mechanisms of each step of this response are not yet known. We have developed a model to study single cell wound repair using the early Drosophila embryo. Our system combines genetics and live imaging tools, allowing us to dissect in vivo the dynamics of the single cell wound response. We have shown that cell wound repair in Drosophila requires the coordinated activities of plasma membrane and cytoskeleton components. Furthermore, we identified an unexpected role for E-cadherin as a link between the contractile actomyosin ring and the newly formed plasma membrane plug. PMID:21922041

  8. Mast Cell Function

    PubMed Central

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

  9. Cell to substratum and cell to cell interactions of microalgae.

    PubMed

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems. PMID:24004676

  10. Lung Cell Oxidant Injury

    PubMed Central

    Suttorp, Norbert; Simon, Lawrence M.

    1982-01-01

    The oxidant damage of lung tissue during in vivo hyperoxic exposure appears to be amplified by neutrophils that release toxic amounts of oxygen metabolites. In our studies cloned lung epithelial cells (L2 cells), lung fibroblasts, and pulmonary artery endothelial cells were cultured under either ambient (Po2 ∼ 140 torr) or hyperoxic (Po2 ∼ 630 torr) conditions for 48 h (24 h for endothelial cells). After cultivation, phorbol myristate acetate- or opsonized zymosan-stimulated neutrophils were added to the cultivated monolayers for 4 h, and lung cell damage was quantitated using 51Cr release as an index. The data show that stimulated neutrophils are able to injure the three lung cell lines tested, with endothelial cells being highly susceptible to this injury and L2 cells being slightly more susceptible than lung fibroblasts. The studies also demonstrate that all three lung cell lines exposed to sustained hyperoxia are more susceptible to neutrophil-mediated cytotoxicity than their time-matched air controls. Hydrogen peroxide was the main toxic oxygen metabolite because catalase (2,500 U/ml) completely protected the target cells. Equivalent quantities of hydrogen peroxide generated by glucose oxidase instead of by neutrophils gave a similar degree of target cell injury. Superoxide dismutase at high concentrations (250 μg/ml) provided some protection. Other systems that detoxify oxygen metabolites were without protective effect. These findings indicate that the increase in susceptibility of lung cells to neutrophil-mediated oxidant damage is a toxic effect of hyperoxia on lung cells. This specific manifestation of oxygen damage provides insight into the integration between primary mechanisms (oxygen exposure) and secondary mechanisms (release of oxygen metabolites by neutrophils) with respect to the cellular basis for pulmonary oxygen toxicity. PMID:6284800

  11. The Chlamydomonas Cell Cycle

    PubMed Central

    Cross, Frederick R.; Umen, James G.

    2015-01-01

    The position of Chlamydomonas within the eukaryotic phylogeny makes it a unique model in at least two important ways: as a representative of the critically important, early-diverging lineage leading to plants, and as a microbe retaining important features of the last eukaryotic common ancestor (LECA) that have been lost in the highly studied yeast lineages. Its cell biology has been studied for many decades, and it has well-developed experimental genetic tools, both classical (Mendelian) and molecular. Unlike land plants, it is a haploid with very few gene duplicates, making it ideal for loss-of-function genetic studies. The Chlamydomonas cell cycle has a striking temporal and functional separation between cell growth and rapid cell divisions, probably connected to the interplay between diurnal cycles that drive photosynthetic cell growth with the cell division cycle; it also exhibits a highly choreographed interaction between the cell cycle and its centriole/basal body/flagellar cycle. Here we review the current status of studies of the Chlamydomonas cell cycle. We begin with an overview of cell cycle control in the well-studied yeast and animal systems, which has yielded a canonical, well-supported model. We discuss briefly what is known about similarities and differences in plant cell cycle control compared to this model. We next review the cytology and cell biology of the multiple fission cell cycle of Chlamydomonas. Lastly we review recent genetic approaches and insights into Chlamydomonas cell cycle regulation that have been enabled by a new generation of genomics-based tools. PMID:25690512

  12. Successful differentiation to T cells, but unsuccessful B-cell generation, from B-cell-derived induced pluripotent stem cells.

    PubMed

    Wada, Haruka; Kojo, Satoshi; Kusama, Chie; Okamoto, Naoki; Sato, Yorino; Ishizuka, Bunpei; Seino, Ken-ichiro

    2011-01-01

    Forced expression of certain transcription factors in somatic cells results in generation of induced pluripotent stem (iPS) cells, which differentiate into various cell types. We investigated T-cell and B-cell lineage differentiation from iPS cells in vitro. To evaluate the impact of iPS cell source, murine splenic B-cell-derived iPS (B-iPS) cells were generated after retroviral transduction of four transcription factors (Oct4, Sox2, Klf4 and c-Myc). B-iPS cells were identical to embryonic stem (ES) cells and mouse embryonic fibroblast (MEF)-derived iPS cells in morphology, ES cell marker expression as well as teratoma and chimera mouse formation. Both B-iPS and MEF-derived iPS cells differentiated into lymphocytes in OP9 co-culture systems. Both efficiently differentiated into T-cell lineage that produced IFN-γ on T-cell receptor stimulation. However, iPS cells including B-iPS cells were relatively resistant to B-cell lineage differentiation. One of the reasons of the failure of B-cell lineage differentiation seemed due to a defect of Pax5 expression in the differentiated cells. Therefore, current in vitro differentiation systems using iPS cells are sufficient for inducing T-cell but not B-cell lineage. PMID:21135032

  13. Cell adhesion in regulation of asymmetric stem cell division

    PubMed Central

    Yamashita, Yukiko M.

    2010-01-01

    Adult stem cells inevitably communicate with their cellular neighbors within the tissues they sustain. Indeed, such communication, particularly with components of the stem cell niche, is essential for many aspects of stem cell behavior, including the maintenance of stem cell identity and asymmetric cell division. Cell adhesion mediates this communication by placing stem cells in close proximity to the signaling source and by providing a polarity cue that orients stem cells. Here, I review the recent discovery that cell adhesion molecules govern the behavior of stem cells. PMID:20724132

  14. New cell sources for T cell engineering and adoptive immunotherapy.

    PubMed

    Themeli, Maria; Rivière, Isabelle; Sadelain, Michel

    2015-04-01

    The promising clinical results obtained with engineered T cells, including chimeric antigen receptor (CAR) therapy, call for further advancements to facilitate and broaden their applicability. One potentially beneficial innovation is to exploit new T cell sources that reduce the need for autologous cell manufacturing and enable cell transfer across histocompatibility barriers. Here we review emerging T cell engineering approaches that utilize alternative T cell sources, which include virus-specific or T cell receptor-less allogeneic T cells, expanded lymphoid progenitors, and induced pluripotent stem cell (iPSC)-derived T lymphocytes. The latter offer the prospect for true off-the-shelf, genetically enhanced, histocompatible cell therapy products. PMID:25842976

  15. Oral Rigosertib for Squamous Cell Carcinoma

    ClinicalTrials.gov

    2016-05-18

    Head and Neck Squamous Cell Carcinoma; Anal Squamous Cell Carcinoma; Lung Squamous Cell Carcinoma; Cervical Squamous Cell Carcinoma; Esophageal Squamous Cell Carcinoma; Skin Squamous Cell Carcinoma; Penile Squamous Cell Carcinoma

  16. Cell-Substrate Adhesion by Amoeboid Cells

    NASA Astrophysics Data System (ADS)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  17. Cell Therapy in Dermatology

    PubMed Central

    Petrof, Gabriela; Abdul-Wahab, Alya; McGrath, John A.

    2014-01-01

    Harnessing the regenerative capacity of keratinocytes and fibroblasts from human skin has created new opportunities to develop cell-based therapies for patients. Cultured cells and bioengineered skin products are being used to treat patients with inherited and acquired skin disorders associated with defective skin, and further clinical trials of new products are in progress. The capacity of extracutaneous sources of cells such as bone marrow is also being investigated for its plasticity in regenerating skin, and new strategies, such as the derivation of inducible pluripotent stem cells, also hold great promise for future cell therapies in dermatology. This article reviews some of the preclinical and clinical studies and future directions relating to cell therapy in dermatology, particularly for inherited skin diseases associated with fragile skin and poor wound healing. PMID:24890834

  18. Concentrator silicon cell research

    SciTech Connect

    Green, M.A.; Wenham, S.R.; Zhang, F.; Zhao, J.; Wang, A.

    1992-04-01

    This project continued the developments of high-efficiency silicon concentrator solar cells with the goal of achieving a cell efficiency in the 26 to 27 percent range at a concentration level of 150 suns of greater. The target efficiency was achieved with the new PERL (passivated emitter, rear locally diffused) cell structure, but only at low concentration levels around 20 suns. The PERL structure combines oxide passivation of both top and rear surfaces of the cells with small area contact to heavily doped regions on the top and rear surfaces. Efficiency in the 22 to 23 percent range was also demonstrated for large-area concentrator cells fabricated with the buried contact solar cell processing sequence, either when combined with prismatic covers or with other innovative approaches to reduce top contact shadowing. 19 refs.

  19. Aneuploidy in stem cells

    PubMed Central

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to reality. However, as somatic cells might have accumulated various chromosomal abnormalities, including aneuploidies throughout their lives, the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated, or worse, become at risk of adopting a malignant fate. In this review, we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore, we review the differences between how somatic cells and stem cells respond to aneuploidy. PMID:27354891

  20. Solar cell shingle

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G. (Inventor)

    1977-01-01

    A solar cell shingle was made of an array of solar cells on a lower portion of a substantially rectangular shingle substrate made of fiberglass cloth or the like. The solar cells may be encapsulated in flourinated ethylene propylene or some other weatherproof translucent or transparent encapsulant to form a combined electrical module and a roof shingle. The interconnected solar cells were connected to connectors at the edge of the substrate through a connection to a common electrical bus or busses. An overlap area was arranged to receive the overlap of a cooperating similar shingle so that the cell portion of the cooperating shingle may overlie the overlap area of the roof shingle. Accordingly, the same shingle serves the double function of an ordinary roof shingle which may be applied in the usual way and an array of cooperating solar cells from which electrical energy may be collected.

  1. Cell Salvage in Obstetrics.

    PubMed

    Goucher, Haley; Wong, Cynthia A; Patel, Samir K; Toledo, Paloma

    2015-08-01

    Intraoperative cell salvage is a strategy to decrease the need for allogeneic blood transfusion. Traditionally, cell salvage has been avoided in the obstetric population because of the perceived risk of amniotic fluid embolism or induction of maternal alloimmunization. With advances in cell salvage technology, the risks of cell salvage in the obstetric population parallel those in the general population. Levels of fetal squamous cells in salvaged blood are comparable to those in maternal venous blood at the time of placental separation. No definite cases of amniotic fluid embolism have been reported and appear unlikely with modern equipment. Cell salvage is cost-effective in patients with predictably high rates of transfusion, such as parturients with abnormal placentation. PMID:26197375

  2. Traction in smooth muscle cells varies with cell spreading

    NASA Technical Reports Server (NTRS)

    Tolic-Norrelykke, Iva Marija; Wang, Ning

    2005-01-01

    Changes in cell shape regulate cell growth, differentiation, and apoptosis. It has been suggested that the regulation of cell function by the cell shape is a result of the tension in the cytoskeleton and the distortion of the cell. Here we explore the association between cell-generated mechanical forces and the cell morphology. We hypothesized that the cell contractile force is associated with the degree of cell spreading, in particular with the cell length. We measured traction fields of single human airway smooth muscle cells plated on a polyacrylamide gel, in which fluorescent microbeads were embedded to serve as markers of gel deformation. The traction exerted by the cells at the cell-substrate interface was determined from the measured deformation of the gel. The traction was measured before and after treatment with the contractile agonist histamine, or the relaxing agonist isoproterenol. The relative increase in traction induced by histamine was negatively correlated with the baseline traction. On the contrary, the relative decrease in traction due to isoproterenol was independent of the baseline traction, but it was associated with cell shape: traction decreased more in elongated than in round cells. Maximum cell width, mean cell width, and projected area of the cell were the parameters most tightly coupled to both baseline and histamine-induced traction in this study. Wide and well-spread cells exerted larger traction than slim cells. These results suggest that cell contractility is controlled by cell spreading.

  3. Entosis and Related Forms of Cell Death within Cells.

    PubMed

    Wang, Y; Wang, X-D

    2015-01-01

    By eliminating the unneeded or mutant cells, programmed cell death actively participates in a wide range of biological processes from embryonic development to homeostasis maintenance in adult. Continuing efforts have identified multiple cell death pathways, with apoptosis, necrosis and autophage the mostly studied. Recently a unique cell death pathway called "cell-in-cell death" has been defined. Unlike traditional cell death pathways, cell-in-cell death, characterized by cell death within another cell, is triggered by the invasion of one cell into its neighbor and executed by either lysosome-dependent degradation or caspase-dependent apoptosis. With remarkable progresses on cell-in-cell over past few years, multiple mechanisms, including entosis, cannibalism and emperitosis, are found to be responsible for cell-in-cell death. Some key questions, such as specific biochemical markers to distinguish precisely the properties of different cell-in-cell structures and the physiological and pathological relevance, remain to be addressed. In light of this situation and a surge of interests, leading scientists in this field intend to share with readers current research progresses on cell-in-cell structures from different model systems through this special edition on cell-in-cell. The mechanistic advances will be highlighted while the future researches be speculated. PMID:26511710

  4. Quantitative methods for analyzing cell-cell adhesion in development.

    PubMed

    Kashef, Jubin; Franz, Clemens M

    2015-05-01

    During development cell-cell adhesion is not only crucial to maintain tissue morphogenesis and homeostasis, it also activates signalling pathways important for the regulation of different cellular processes including cell survival, gene expression, collective cell migration and differentiation. Importantly, gene mutations of adhesion receptors can cause developmental disorders and different diseases. Quantitative methods to measure cell adhesion are therefore necessary to understand how cells regulate cell-cell adhesion during development and how aberrations in cell-cell adhesion contribute to disease. Different in vitro adhesion assays have been developed in the past, but not all of them are suitable to study developmentally-related cell-cell adhesion processes, which usually requires working with low numbers of primary cells. In this review, we provide an overview of different in vitro techniques to study cell-cell adhesion during development, including a semi-quantitative cell flipping assay, and quantitative single-cell methods based on atomic force microscopy (AFM)-based single-cell force spectroscopy (SCFS) or dual micropipette aspiration (DPA). Furthermore, we review applications of Förster resonance energy transfer (FRET)-based molecular tension sensors to visualize intracellular mechanical forces acting on cell adhesion sites. Finally, we describe a recently introduced method to quantitate cell-generated forces directly in living tissues based on the deformation of oil microdroplets functionalized with adhesion receptor ligands. Together, these techniques provide a comprehensive toolbox to characterize different cell-cell adhesion phenomena during development. PMID:25448695

  5. Improving Cell Engraftment in Cardiac Stem Cell Therapy

    PubMed Central

    Xie, Xiaoyun

    2016-01-01

    Myocardial infarction (MI) affects millions of people worldwide. MI causes massive cardiac cell death and heart function decrease. However, heart tissue cannot effectively regenerate by itself. While stem cell therapy has been considered an effective approach for regeneration, the efficacy of cardiac stem cell therapy remains low due to inferior cell engraftment in the infarcted region. This is mainly a result of low cell retention in the tissue and poor cell survival under ischemic, immune rejection and inflammatory conditions. Various approaches have been explored to improve cell engraftment: increase of cell retention using biomaterials as cell carriers; augmentation of cell survival under ischemic conditions by preconditioning cells, genetic modification of cells, and controlled release of growth factors and oxygen; and enhancement of cell survival by protecting cells from excessive inflammation and immune surveillance. In this paper, we review current progress, advantages, disadvantages, and potential solutions of these approaches. PMID:26783405

  6. Impacts of fishing and environmental factors driving changes on littoral fish assemblages in a subtropical oceanic island

    NASA Astrophysics Data System (ADS)

    Sangil, Carlos; Martín-García, Laura; Hernández, José Carlos; Concepción, Laura; Fernández, Raúl; Clemente, Sabrina

    2013-08-01

    The structure of demersal fish assemblages of commercial interest was studied at 51 sites on La Palma Island (Canary Islands, northeastern Atlantic). On this island, demersal fish populations are limited and independent from other islands. As deep water separates the islands and the shallow sublittoral platforms are not continuous, adult inter-island migrations are not possible except between the islands of Lanzarote and Fuerteventura. Otherwise, each island functions as a closed system, and the status of an island fish assemblage depends on local environmental conditions and activities performed in situ by the islanders. These circumstances provide a unique opportunity to test the intrainsular variability of fish assemblages. With this background, environmental parameters, fishing pressure and distance to the MPA were considered to identify the main factors explaining the spatial variation of fish assemblages off La Palma Island. Twenty-six fish species were recorded, but 60% of the total fish biomass was represented by only five species (Sparisoma cretense, Pomadasys incisus, Canthidermis sufflamen, Diplodus cervinus cervinus and Bodianus scrofa). However, the structure of assemblages was heterogeneous in response to different variables and showed substantial spatial variation. The assemblages were strongly modified by the presence of upright seaweed cover, fishing activities, and certain environmental variables. Differences were more pronounced in species that occupied the higher trophic levels. The most disturbed assemblages were those located in areas with lower upright seaweed cover and with higher fishing pressure, whereas the best-preserved assemblages corresponded to sites with controlled fishing activities, located within the MPA.

  7. Synthesis of the quaternary in the almeria littoral neotectonic activity and its morphologic features, western betics, Spain

    NASA Astrophysics Data System (ADS)

    Goy, J. L.; Zazo, C.

    1986-11-01

    A sequence of marine and continental Quaternary episodes is established, as are their interrelationships. The zone's tectonics have, in most cases, remained active to the present and control the factors All the Tyrrhenian levels containing Strombus bubonius are affected by the many faults that cross the lateral fringe and continue onto the shelf. Among these are: the Loma del Viento Fault, (N120°E. a normal fault with certain leftward characteristics): the El Alquian faults (N140°, 160°E, which coincide, according to several authors (Bousquet, 1979), with the surface feature of a great dextral deep accident); and the Carboneras Fault, or the Serrata Fault, (N40°, 45°E, left strike-slip fault). Given the varying behaviour of the shoreline, we have chosen to divide it into four sectors: Campo de Dalias, El-Alquian-Cabo de Gata, Mojacar—Garrucha. and Campo de Nijar-Serrata. Due to its geographical location, no marine-continental relationships exist in the latter. A chart has been made in an attempt to synthesize the most significant stratigraphic, genetic and tectonic characteristics of each sector. Lastly, the influence of tectonics on the distribution and heights of the Quaternary shorelines is clearly shown in a chart of the transgressive maxima of the Tyrrhenian episodes.

  8. [Nutrient Characteristics and Nitrogen Forms of Rhizosphere Soils Under Four Typical Plants in the Littoral Zone of TGR].

    PubMed

    Wang, Xiao-feng; Yuan, Xing-zhong; Liu, Hong; Zhang, Lei; Yu, Jian-jun; Yue, Jun-sheng

    2015-10-01

    The Three Gorges Reservoir (TGR), which is the largest water conservancy project ever built in tne world, produced a drawdown area of about 348.93 km2 because of water level control. The biological geochemical cycle of the soil in the drawdown zone has been changed as the result of long-term winter flooding and summer drought and vegetation covering. The loss of soil nitrogen in the drawdown zone poses a threat to the water environmental in TGR. Pengxi river, is an important anabranch, which has the largest drawdown area has been selected in the present study. The four typical vegetation, contained Cynodon dactylon, Cyperus rotundus, Anthium sibiricum and Zea mays L. as the control, were studied to measure nutrient characteristics and nitrogen forms of rhizosphere and non-rhizosphere soils in three distribution areas with different soil types (paddy soil, purple soil and fluvo-aquic soils). The variables measured included organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), hydrolysis N, available P and available K, pH, ion-exchangeable N (IEE-N), weak acid extractable N (CF-N) , iron-manganese oxides N (IMOF-N), organic matter sulfide N (OSF-N), added up four N forms for total transferable N (TF-N) and TN minus TF-N for non-transferable N (NTF-N). The results showed: (1) pH of rhizosphere soil was generally lower than that of non-rhizosphere soil under different vegetation in different type soils because the possible organic acid and H+ released form plant roots and cation absorption differences, and the OM, TP, TN and hydrolysis N of rhizosphere soil were generally higher than those of non-rhizosphere soil, and that the enrichment ratio (ER) of all the four nutrient indicators showed Cyperus rotundus > Cynodon dactylon > Zea mays L. > Anthium sibiricum. Available P showed enrichment in the rhizosphere of three natural vegetations but lose under corn, and available K, TK showed different ER in different conditions. (2) IEF-N CF-N, IMOF-N, OSF-N and TF-N of rhizosphere soil were generally higher than those of non-rhizosphere soil, but the TF-N to TN ratio in rhizosphere of Cyperus rotundus and Cynodon dactylon were lower than those of non-rhizosphere soil, and in rhizosphere of Anthium sibiricum and Zea mays L. were higher, the rhizosphere effect of different vegetations on the N cycle was significant difference. (3) the correlation between nutrient characteristics and nitrogen forms was evaluated to explore the influence factor for the N forms changing. There was a significant correlation between soil OM and four N forms, TP was significantly correlated with CF-N, OSF-N, TF-N, and soil available P content was significantly negatively correlated with IMOF-N, OSF-N, TF-N and TN. Our research could provide that the drawdown zone covered with Cyperus rotundus and Cynodon dactylon was better than Anthium sibiricum and Zea mays L. to improve soil N holding and fixation. The vegetation recovery in the drawdown zone should consider the rhizosphere effect of different vegetations on N cycle. PMID:26841597

  9. Unattended wireless proximity sensor networks for counterterrorism, force protection, littoral environments, PHM, and tamper monitoring ground applications

    NASA Astrophysics Data System (ADS)

    Forcier, Bob

    2003-09-01

    This paper describes a digital-ultrasonic ground network, which forms an unique "unattended mote sensor system" for monitoring the environment, personnel, facilities, vehicles, power generation systems or aircraft in Counter-Terrorism, Force Protection, Prognostic Health Monitoring (PHM) and other ground applications. Unattended wireless smart sensor/tags continuously monitor the environment and provide alerts upon changes or disruptions to the environment. These wireless smart sensor/tags are networked utilizing ultrasonic wireless motes, hybrid RF/Ultrasonic Network Nodes and Base Stations. The network is monitored continuously with a 24/7 remote and secure monitoring system. This system utilizes physical objects such as a vehicle"s structure or a building to provide the media for two way secure communication of key metrics and sensor data and eliminates the "blind spots" that are common in RF solutions because of structural elements of buildings, etc. The digital-ultrasonic sensors have networking capability and a 32-bit identifier, which provide a platform for a robust data acquisition (DAQ) for a large amount of sensors. In addition, the network applies a unique "signature" of the environment by comparing sensor-to-sensor data to pick up on minute changes, which would signal an invasion of unknown elements or signal a potential tampering in equipment or facilities. The system accommodates satellite and other secure network uplinks in either RF or UWB protocols. The wireless sensors can be dispersed by ground or air maneuvers. In addition, the sensors can be incorporated into the structure or surfaces of vehicles, buildings, or clothing of field personnel.

  10. Performance analysis of a multispectral framing camera for detecting mines in the littoral zone and beach zone

    NASA Astrophysics Data System (ADS)

    Louchard, Eric; Farm, Brian; Acker, Andrew

    2008-04-01

    BAE Systems Sensor Systems Identification & Surveillance (IS) has developed, under contract with the Office of Naval Research, a multispectral airborne sensor system and processing algorithms capable of detecting mine-like objects in the surf zone and land mines in the beach zone. BAE Systems has used this system in a blind test at a test range established by the Naval Surface Warfare Center - Panama City Division (NSWC-PCD) at Eglin Air Force Base. The airborne and ground subsystems used in this test are described, with graphical illustrations of the detection algorithms. We report on the performance of the system configured to operate with a human operator analyzing data on a ground station. A subsurface (underwater bottom proud mine in the surf zone and moored mine in shallow water) mine detection capability is demonstrated in the surf zone. Surface float detection and proud land mine detection capability is also demonstrated. Our analysis shows that this BAE Systems-developed multispectral airborne sensor provides a robust technical foundation for a viable system for mine counter-measures, and would be a valuable asset for use prior to an amphibious assault.

  11. Trophic structure of macrobenthic communities on the Portuguese coast. A review of lagoonal, estuarine and rocky littoral habitats

    NASA Astrophysics Data System (ADS)

    Boaventura, Diana; Cancela da Fonseca, Luís; Teles-Ferreira, Carla

    1999-07-01

    This work is based on a compilation and treatment of data obtained on several studies regarding the macrobenthos trophic structure, carried out in different habitats of the Portuguese coast: a lagoon, rocky subtidal shores and estuarine eelgrass beds. Macrobenthic organisms were assigned to four distinct trophic groups (filter feeders, detritivores, herbivores and carnivores). Detritivores were the dominant trophic group in soft-bottom communities. Filter feeders dominated in subtidal rocky shores while eelgrass communities were equally represented by detritivores and herbivores. Current intensity and sediment deposition are discussed as factors affecting the observed distribution. Nevertheless, different sampling methods used in these studies and the lack of information on feeding habits of some species can also influence the results obtained.

  12. New Acotylea (Polycladida, Platyhelminthes) from the east coast of the North Atlantic Ocean with special mention of the Iberian littoral.

    PubMed

    Noreña, Carolina; Rodríguez, Jorge; Pérez, Jacinto; Almon, Bruno

    2015-01-01

    Polyclad species diversity, although generally well known for European North Atlantic waters, is nearly unknown for the Iberian Peninsula. The "Ría de Arousa", located on the Atlantic coast of Galicia (Spain), is a place where many positive biological factors for species biodiversity converge. Therefore, it is an ideal location to study polyclad diversity. This research, which describes new records and new species, contributes to the knowledge of the distribution of Polycladida (Platyhelminthes), particularly of the suborder Acotylea, in the Atlantic waters of the Iberian Peninsula. The new records include the re-descriptions of Cryptocelis compacta Lang, 1884, Stylochus neapolitanus (Delle Chiaje, 1841-1844) and Discocelis tigrina (Blanchard, 1847), while the two newly described species are Hoploplana elisabelloi n. sp. and Armatoplana celta n. sp. PMID:26624472

  13. Long-term measurements of atmospheric point-spread functions over littoral waters as determined by atmospheric turbulence

    NASA Astrophysics Data System (ADS)

    de Jong, Arie N.; Schwering, Piet B. W.; Benoist, Koen W.; Gunter, Willem H.; Vrahimis, George; October, Faith J.

    2012-06-01

    During the FATMOSE trial, held over the False Bay, South Africa) from November 2009 until October 2010, day and night (24/7) high resolution images were collected of point sources at a range of 15.7 km. Simultaneously, data were collected on atmospheric parameters, as relevant for the turbulence conditions: air- and sea temperature, windspeed, relative humidity and the structure parameter for refractive index: Cn 2. The data provide statistical information on the mean value and the variance of the atmospheric point spread function and the associated modulation transfer function during series of consecutive frames. This information allows the prediction of the range performance for a given sensor, target and atmospheric condition, which is of great importance for the user of optical sensors in related operational areas and for the developers of image processing algorithms. In addition the occurrence of "lucky shots" in series of frames is investigated: occasional frames with locally small blur spots. The simultaneously measured short exposure blur and the beam wander are compared with simultaneously collected scintillation data along the same path and the Cn 2 data from a locally installed scintillometer. By using two vertically separated sources, the correlation is determined between the beam wander in their images, providing information on the spatial extension of the atmospheric turbulence (eddy size). Examples are shown of the appearance of the blur spot, including skewness and astigmatism effects, which manifest themselves in the third moment of the spot and its distortion. An example is given of an experiment for determining the range performance for a given camera and a bar target on an outgoing boat in the False Bay.

  14. EXPANSION RATES AND RECRUITMENT FREQUENCY OF EXOTIC SMOOTH CORDGRASS, SPARTINA ALTERNIFLORA (LOISEL), COLONIZING UNVEGETATED LITTORAL FLATS IN WILLAPA BAY, WASHINGTON

    EPA Science Inventory

    We estimated lateral growth rates of nonindigenous Spartina alerniflora patches in Willapa Bay, Washington, over three intervals between 1970 and 1990, to reconstruct recruitment frequency since S. alterniflora was initially introduced c.l890. Black and white aerial photographs ...

  15. Influence of bioturbation on the biogeochemistry of littoral sediments of an acidic post-mining pit lake

    NASA Astrophysics Data System (ADS)

    Lagauzère, S.; Moreira, S.; Koschorreck, M.

    2011-02-01

    In the last decades, the mining exploitation of large areas in Lusatia (Eastern Germany) but also in other mining areas worldwide has led to the formation of hundreds of pit lakes. Pyrite oxidation in the surrounding dumps makes many such lakes extremely acidic (pH < 3). The biogeochemical functioning of these lakes is mainly governed by cycling of iron. This represents a relevant ecological problem and intensive research has been conducted to understand the involved biogeochemical processes and develop bioremediation strategies. Despite some studies reporting the presence of living organisms (mostly bacteria, algae, and macro-invertebrates) under such acidic conditions, and their trophic interactions, their potential impact on the ecosystem functioning was poorly investigated. The present study aimed to assess the influence of chironomid larvae on oxygen dynamics and iron cycle in the sediment of acidic pit lakes. In the Mining Lake 111, used as a study case since 1996, Chironomus crassimanus (Insecta, Diptera) is the dominant benthic macro-invertebrate species and occurs at relatively high abundances in shallow water. A 16-day laboratory experiment using microcosms combined with high resolution measurements (DET gel probes and O2 microsensors) was carried out. The burrowing activity of C. crassimanus larvae induced a 3-fold increase of the diffusive oxygen uptake by sediment, indicating a stimulation of the mineralization of organic matter in the upper layers of the sediment. The iron cycle was also impacted (e.g. lower rates of reduction and oxidation, increase of iron-oxidizing bacteria abundance, stimulation of mineral formation) but with no significant effect on the iron flux at the sediment-water interface, and thus on the water acidity budget. This work provides the first assessment of bioturbation in an acidic mining lake and shows that its influence on biogeochemistry cannot be neglected.

  16. Influence of bioturbation on the biogeochemistry of the sediment in the littoral zone of an acidic mine pit lake

    NASA Astrophysics Data System (ADS)

    Lagauzère, S.; Moreira, S.; Koschorreck, M.

    2010-10-01

    In the last decades, the mining exploitation of large areas in Lusatia (South-eastern Germany) but also in other mining areas worldwide has led to the formation of hundreds of pit lakes. Pyrite oxidation in the surrounding dumps makes many such lakes extremely acidic (pH < 3). The biogeochemical functioning of these lakes is mainly governed by cycling of iron. This represents a relevant ecological problem and intensive research has been conducted to understand the involved biogeochemical processes and develop bioremediation strategies. Despite some studies reporting the presence of living organisms (mostly bacteria, algae, and macro-invertebrates) under such acidic conditions, and their trophic interactions, their potential impact on the ecosystem functioning was poorly investigated. The present study aimed to assess the influence of chironomid larvae on oxygen dynamics and iron cycle in the sediment of acidic pit lakes. In the Mining Lake 111, used as a study case since 1996, Chironomus crassimanus (Insecta, Diptera) is the dominant benthic macro-invertebrate species and occurs at relatively high abundances in shallow water. A 16-day laboratory experiment using microcosms combined with high resolution measurements (DET gel probes and O2 microsensors) was carried out. The burrowing activity of C. crassimanus larvae induced a 3-fold increase of the oxygen consumption by sediment, and stimulated the mineralization of organic matter in the upper layers of the sediment. The iron cycle was also impacted (e.g. lower rates of reduction and oxidation, increase of iron-oxidizing bacteria abundance, stimulation of mineral formation) but with no significant effect on the iron flux at the sediment-water interface, and thus on the water acidity budget. This work provides the first assessment of bioturbation in an acidic mining lake and shows that its influence on biogeochemistry cannot be neglected.

  17. Nationally consistent and easily-implemented approach to evaluate littoral-riparian habitat quality in lakes and reservoirs

    EPA Science Inventory

    The National Lakes Assessment (NLA) and other lake survey and monitoring efforts increasingly rely upon biological assemblage data to define lake condition. Information concerning the multiple dimensions of physical and chemical habitat is necessary to interpret this biological ...

  18. Characterization of Amniotic Stem Cells

    PubMed Central

    Koike, Chika; Zhou, Kaixuan; Takeda, Yuji; Fathy, Moustafa; Okabe, Motonori; Yoshida, Toshiko; Nakamura, Yukio; Kato, Yukio

    2014-01-01

    Abstract The amnion membrane is developed from embryo-derived cells, and amniotic cells have been shown to exhibit multidifferentiation potential. These cells represent a desirable source for stem cells for a variety of reasons. However, to date very few molecular analyses of amnion-derived cells have been reported, and efficient markers for isolating the stem cells remain unclear. This paper assesses the characterization of amnion-derived cells as stem cells by examining stemness marker expressions for amnion-derived epithelial cells and mesenchymal cells by flow cytometry, immunocytochemistry, and quantitative PCR. Flow cytometry revealed that amnion epithelial cells expressed CD133, CD 271, and TRA-1-60, whereas mecenchymal cells expressed CD44, CD73, CD90, and CD105. Immunohistochemistry showed that both cells expressed the stemness markers Oct3/4, Sox2, Klf4, and SSEA4. Stemness genes' expression in amnion epithelial cells, mesenchymal cells, fibroblast, bone marrow–derived mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) was compared by quantitative reverse-transcription polymerase chain reaction (RT-PCR). Amnion-derived epithelial cells and mesenchymal cells expressed Oct3/4, Nanog, and Klf4 more than bone marrow–derived MSCs. The sorted TRA1-60–positive cells expressed Oct3/4, Nanog, and Klf4 more than unsorted cells or TRA1-60–negative cells. TRA1-60 can be a marker for isolating amnion epithelial stem cells. PMID:25068631

  19. Paratesticular Spindle Cell Rhabdomyosarcoma

    PubMed Central

    Dey, Biswajit; Bharti, Jyotsna Naresh; Dange, Prasad; Desai, Parth Anil; Khurana, Nita; Chander, Jagdish

    2015-01-01

    Spindle cell rhabdomyosarcoma is a rare variant of embryonal rhabdomyosarcoma that affects young males and most commonly involves the paratesticular region. We report a case of paratesticular spindle cell rhabdomyosarcoma in a 14-year-old boy, who presented with a painless scrotal mass. Left inguinal orchidectomy was performed. Histopathological and immunohistochemical examination of the mass revealed spindle cell rhabdomyosarcoma of the paratesticular region. PMID:26500726

  20. Rechargeable Magnesium Power Cells

    NASA Technical Reports Server (NTRS)

    Koch, Victor R.; Nanjundiah, Chenniah; Orsini, Michael

    1995-01-01

    Rechargeable power cells based on magnesium anodes developed as safer alternatives to high-energy-density cells like those based on lithium and sodium anodes. At cost of some reduction in energy density, magnesium-based cells safer because less susceptible to catastrophic meltdown followed by flames and venting of toxic fumes. Other advantages include ease of handling, machining, and disposal, and relatively low cost.