Hierarchical den selection of Canada lynx in western Montana

Treesearch

John R. Squires; Nicholas J. Decesare; Jay A. Kolbe; Leonard F. Ruggiero

2008-01-01

We studied den selection of Canada lynx (Lynx canadensis; hereafter lynx) at multiple ecological scales based on 57 dens from 19 females located in western Montana, USA, between 1999 and 2006. We considered 3 spatial scales in this analysis, including den site (11-m-radius circle surrounding dens), den area (100-m-radius circle), and den environ (1-...

Denning of grizzly bears in the Yellowstone National Park area

USGS Publications Warehouse

Judd, Steven L.; Knight, Richard R.; Blanchard, Bonnie M.

1986-01-01

Radiotelemetry was used to locate 101 grizzly bear (Ursus arctos) dens from 1975 to 1980; 35 dens were examined on the ground. Pregnant females denned in late October, and most other bears denned by mid-November. Duration of denning average 113, 132, and 170 days for males, females, and females with new cubs, respectively. Males emerged from mid-February to late March, followed by single females and females with yearlings and 2-year-olds. Females with new cubs emerged from early mid-April. Den sites were associated with moderate tree cover (26%-75% canopy cover) on 30°-60° slopes. Dens occurred on all aspects, although northerly exposures were most common. Grizzly bears usually dug new dens but occasionally used natural cavities or a den from a previous year. Males usually dug larger dens than females with young. Eight excavated and 2 natural dens of the 35 examined dens were used for more than 1 year.

[Education in anatomy initiated by Pompe van Meerdervoort].

PubMed

Koji, Takehiko; Aikawa, Tadaomi

2008-12-01

Pompe van Meerdervoort arrived at Nagasaki port on September 21, 1857 and started his western-style medical education for the first time in the Nishiyakusho of Nagasaki on November 12, 1857. He had 12 students including Ryojun Matsumono. The curriculum was largely based on that of Utrecht Army Medical School, which was re-organized after 1841 and very good in balance of theory and practice. Among subjects, much attention was paid for Anatomy which was quite advancing at the time and in fact the lecture was given on every Tuesday, Thursday and Saturday morning from 1857 to the end of 1859. His lecture note on Anatomy was based on Handboek der Ontleedkunde van den Mensch originally written by C. E. Bock, which was translated into Dutch by P. H. Pool. The note currently available is a copy by the students. In Europe of those days, microscopes were developed and "Histology" had been established as a new science. Therefore, his lecture contained details of histological findings and now we can appreciate his policy to think much of Anatomy in the introduction of western-style medical education.

Detecting denning polar bears with Forward-Looking Infrared (FLIR) imagery

USGS Publications Warehouse

Amstrup, Steven C.; York, G.; McDonald, T.L.; Nielson, R.; Simac, K.

2004-01-01

Polar bears give birth in snow dens in midwinter and remain in dens until early spring. The survival and development of cubs is dependent on a stable environment within the maternal den. To mitigate potential disruption of polar bear denning by existing and proposed petroleum activities, we used forward-looking infrared (FLIR) viewing to try to detect heat rising from dens.We flew transects over dens of radio-collared females with FLIR imager-equipped aircraft, recorded weather conditions at each observation, and noted whether the den was detected.We surveyed 23 dens on 67 occasions (1 to 7 times each). Nine dens were always detected, and 10 dens visited more than once were detected on some flights but not on others. Four dens were never detected (17 percent), but three of those were visited only under marginal conditions. The odds of detecting a den were 4.8 times greater when airborne moisture (snow, blowing snow, fog, etc.) was absent than when it was present, and they increased 3-fold for every 1?C increase in temperature-dew point spread. The estimated probability of detecting dens in sunlight was 0. Data suggested that FLIR surveys conducted during optimal conditions for detection can produce detection rates approaching 90 percent and thus can be an important management and mitigation tool. polar bear, infrared imagery, maternal denning, human impacts, management

American black bear denning behavior: Observations and applications using remote photography

USGS Publications Warehouse

Bridges, A.S.; Fox, J.A.; Olfenbuttel, C.; Vaughan, M.B.

2004-01-01

Researchers examining American black bear (Ursus americanus) denning behavior have relied primarily on den-site visitation and radiotelemetry to gather data. Repeated den-site visits are time-intensive and may disturb denning bears, possibly causing den abandonment, whereas radiotelemetry is sufficient only to provide gross data on den emergence. We used remote cameras to examine black bear denning behavior in the Allegheny Mountains of western Virginia during March-May 2003. We deployed cameras at 10 den sites and used 137 pictures of black bears. Adult female black bears exhibited greater extra-den activity than we expected prior to final den emergence, which occurred between April 12 and May 6, 2003. Our technique provided more accurate den-emergence estimation than previously published methodologies. Additionally, we observed seldom-documented behaviors associated with den exits and estimated cub age at den emergence. Remote cameras can provide unique insights into denning ecology, and we describe their potential application to reproductive, survival, and behavioral research.

Grizzly bear denning chronology and movements in the Greater Yellowstone Ecosystem

USGS Publications Warehouse

Haroldson, Mark A.; Ternent, Mark A.; Gunther, Kerry A.; Schwartz, Charles C.

2002-01-01

Den entrance and emergence dates of grizzly bears (Ursus arctos) in the Greater Yellowstone Ecosystem are important to management agencies that wish to minimize impacts of human activities on bears. Current estimates for grizzly bear denning events use data that were collected from 1975–80. We update these estimates by including data obtained from 1981–99. We used aerial telemetry data to estimate week of den entry and emergence by determining the midpoint between the last known active date and the first known date denned, as well as the last known date denned and the first known active date. We also investigated post emergence movement patterns relative to den locations. Mean earliest and latest week of den entry and emergence were also determined. Den entry for females began during the fourth week in September, with 90% denned by the fourth week of November. Earliest den entry for males occurred during the second week of October, with 90% denned by the second week of December. Mean week of den entry for known pregnant females was earlier than males. Earliest week of den entry for known pregnant females was earlier than other females and males. Earliest den emergence for males occurred during the first week of February, with 90% of males out of dens by the fourth week of April. Earliest den emergence for females occurred during the third week of March; by the first week of May, 90% of females had emerged. Male bears emerged from dens earlier than females. Denning period differed among classes and averaged 171 days for females that emerged from dens with cubs, 151 days for other females, and 131 days for males. Known pregnant females tended to den at higher elevations and, following emergence, remained at higher elevation until late May. Females with cubs remained relatively close (<3 km) to den sites until the last 2 weeks in May. Timing of denning events was similar to previous estimates for this and other grizzly bear populations in the southern Rocky

Genetics Home Reference: bare lymphocyte syndrome type II

MedlinePlus

... 6. Citation on PubMed Gobin SJ, Peijnenburg A, van Eggermond M, van Zutphen M, van den Berg R, van den Elsen PJ. The RFX complex is crucial ... D, Szöllosi J, Jenei A. Bare lymphocyte syndrome: an opportunity to discover our immune system. Immunol Lett. ...

Remote identification of polar bear maternal den habitat in northern Alaska

USGS Publications Warehouse

Durner, George M.; Amstrup, Steven C.; Ambrosius, Ken J.

2001-01-01

Polar bears (Ursus maritimus) give birth in dens of ice and snow to protect their altricial young. During the snow-free season, we visited 25 den sites located previously by radiotelemetry and characterized the den site physiognomy. Seven dens occurred in habitats with minimal relief. Eighteen dens (72%) were in coastal and river banks. These "banks" were identifiable on aerial photographs. We then searched high-resolution aerial photographs (n = 3000) for habitats similar to those of the 18 dens. On aerial photos, we mapped 1782 km of bank habitats suitable for denning. Bank habitats comprised 0.18% of our study area between the Colville River and the Tamayariak River in northern Alaska. The final map, which correctly identified 88% of bank denning habitat in this region, will help minimize the potential for disruptions of maternal dens by winter petroleum exploration activities.

Denning behaviour of non-gravid wolves, Canis lupus

USGS Publications Warehouse

Mech, L.D.; Phillips, M.K.; Smith, D.W.; Kreeger, T.J.

1996-01-01

Wild wolves (Canis lupus) that had produced pups in earlier years but were not currently pregnant, and ovariectomized captive wolves, dug dens during and after the whelping season even though they produced no pups. These observations suggest that den digging is not a function of pregnancy or of ovarian estrogen or progesterone. We hypothesize that increasing prolactin in spring elicits or mediates den-digging behavior.

Selection of den sites by black bears in the southern Appalachians

USGS Publications Warehouse

Reynolds-Hogland, M. J.; Mitchell, M.S.; Powell, R.A.; Brown, D.C.

2007-01-01

We evaluated selection of den sites by American black bears (Ursus americanus) in the Pisgah Bear Sanctuary, western North Carolina, by comparing characteristics of dens at 53 den sites with availability of habitat characteristics in annual home ranges of bears and in the study area. We also tested whether den-site selection differed by sex, age, and reproductive status of bears. In addition, we evaluated whether the den component of an existing habitat model for black bears predicted where bears would select den sites. We found bears selected den sites far from gravel roads, on steep slopes, and at high elevations relative to what was available in both annual home ranges and in the study area. Den-site selection did not differ by sex or age, but it differed by reproductive status. Adult females with cubs preferred to den in areas that were relatively far from gravel roads, but adult females without cubs did not. The habitat model overestimated the value of areas near gravel roads, underestimated the value of moderately steep areas, and did not include elevation as a predictor variable. Our results highlight the importance of evaluating den selection in terms of both use and availability of den characteristics. ?? 2007 American Society of Mammalogists.

Entropy and time: A search for Denning's resting place

NASA Astrophysics Data System (ADS)

Beech, Martin

2013-04-01

The interminable scientific literature reveals William Frederick Denning (1848-1931) as one of the great practitioners of meteor astronomy: he wrote widely on the subject and dedicated innumerable hours to his observations. But who was Denning? What can we learn of his life, living and death. Glimpses of Denning the man do exist, but he is largely a man of translucency and unknowns. The journey recounted here reflects upon a recent search for Denning's final resting place, but, once again, it is found that time and circumstance have erased virtually all of the physical history.

Habitat characteristics of polar bear terrestrial maternal den sites in northern Alaska

USGS Publications Warehouse

Durner, George M.; Amstrup, Steven C.; Fischbach, Anthony S.

2003-01-01

Polar bears (Ursus maritimus) give birth to and nurture their young in dens of ice and snow. During 1999-2001, we measured the structure of 22 dens on the coastal plain of northern Alaska after polar bear families had evacuated their dens in the spring. During the summers of 2001 and 2002, we revisited the sites of 42 maternal and autumn exploratory dens and recorded characteristics of the under-snow habitat. The structure of polar bear snow dens was highly variable. Most were simple chambers with a single entrance/egress tunnel. Others had multiple chambers and additional tunnels. Thickness of snow above and below dens was highly variable, but most dens were overlain by less than 1 m of snow. Dens were located on, or associated with, pronounced landscape features (primarily coastal and river banks, but also a lake shore and an abandoned oil field gravel pad) that are readily distinguished from the surrounding terrain in summer and catch snow in early winter. Although easily identified, den landforms in northern Alaska were more subtle than den habitats in many other parts of the Arctic. The structure of polar bear dens in Alaska was strikingly similar to that of dens elsewhere and has remained largely unchanged in northern Alaska for more than 25 years. Knowledge of den structure and site characteristics will allow resource managers to identify habitats with the greatest probability of holding dens. This information may assist resource managers in preventing negative impacts of mineral exploration and extraction on polar bears.

Geluidsexpositie bij Gebruik van Otoplastieken met Communicatie (Sound Exposure Level of F-16 Crew Chiefs Using Custom Molded Communications Earplugs)

DTIC Science & Technology

2008-10-01

346 35 39 77 lnfo-DenV@tno nl Datum oktober 2008 Auteur (s) dr. ir. MM..I. Houben J.A. Verhave Rubricering rapport Ongerubriceerd Vastgesteld... Auteur (s) dr. ir. M.M.J. Houben J.A. Verhave Rubricering rapport Ongerubriceerd TNO-rapport | TNO-DV 2008 A395 4/19 Summary Sound exposure level...ontwikkeld om de geluidsexpositie van CEPs te bepalen (TNO-project 032.13072, rapport TNO-DV 2008 A054) [1], In theorie kan het totale

Diversity of Tn1546 in vanA-positive Enterococcus faecium clinical isolates with VanA, VanB, and VanD phenotypes and susceptibility to vancomycin.

PubMed

Cha, J O; Yoo, J I; Kim, H K; Kim, H S; Yoo, J S; Lee, Y S; Jung, Y H

2013-10-01

To investigate diversity in the vanA cluster in Enterococcus faecium isolates from nontertiary hospitals. We identified 43 vanA-positive Ent. faecium isolates, including two vancomycin-susceptible isolates, from hospitals between 2003 and 2006. Of these isolates, >85% were resistant to ampicillin, erythromycin and ciprofloxacin. The vanA cluster was classified into six types using overlapping PCR, but the prototype transposon Tn1546 was not found. Most vanA-positive vancomycin-resistant Enterococcus (VRE) carried IS1216V and belonged to Type III (58·1%) or Type II (20·9%). vanY, vanZ and IS1216V were observed in the left and right ends of Type III with long-range PCR. IS1216V was also observed within vanS and vanX in the two vancomycin-susceptible isolates and in two vancomycin-resistant isolates. No VRE isolates with VanB and VanD phenotypes contained point mutations in vanS, unlike in previous reports. Sequence types (STs) of all isolates belonged to clonal complex 17, and ST78 was predominant. Insertion sequences, especially IS1216V, cause structural variation in the vanA cluster. We report the first observation of vanY and vanZ at the left end of Tn1546 in clinical isolates. This is the first report of the frequency of vancomycin resistance and diversity of Tn1546 in vanA-positive Ent. faecium isolates from nontertiary hospitals. © 2013 The Society for Applied Microbiology.

A female black bear denning habitat model using a geographic information system

USGS Publications Warehouse

Clark, J.D.; Hayes, S.G.; Pledger, J.M.

1998-01-01

We used the Mahalanobis distance statistic and a raster geographic information system (GIS) to model potential black bear (Ursus americanus) denning habitat in the Ouachita Mountains of Arkansas. The Mahalanobis distance statistic was used to represent the standard squared distance between sample variates in the GIS database (forest cover type, elevation, slope, aspect, distance to streams, distance to roads, and forest cover richness) and variates at known bear dens. Two models were developed: a generalized model for all den locations and another specific to dens in rock cavities. Differences between habitat at den sites and habitat across the study area were represented in 2 new GIS themes as Mahalanobis distance values. Cells similar to the mean vector derived from the known dens had low Mahalanobis distance values, and dissimilar cells had high values. The reliability of the predictive model was tested by overlaying den locations collected subsequent to original model development on the resultant den habitat themes. Although the generalized model demonstrated poor reliability, the model specific to rock dens had good reliability. Bears were more likely to choose rock den locations with low Mahalanobis distance values and less likely to choose those with high values. The model can be used to plan the timing and extent of management actions (e.g., road building, prescribed fire, timber harvest) most appropriate for those sites with high or low denning potential. 

Den-site characteristics of black bears in Rocky Mountain National Park, Colorado

USGS Publications Warehouse

Baldwin, R.A.; Bender, L.C.

2008-01-01

We compared historic (1985-1992) and contemporary (2003-2006) black bear (Ursus americanus) den locations in Rocky Mountain National Park (RMNP), Colorado, USA, for habitat and physiographic attributes of den sites and used maximum entropy modeling to determine which factors were most influential in predicting den-site locations. We observed variability in the relationship between den locations and distance to trails and elevation over rime. Locations of historic den sites were most associated with slope, elevation, and covertype, whereas contemporary sites were associated with slope, distance to roads, aspect, and canopy height. Although relationships to covariates differed between historic and contemporary periods, preferred den-site characteristics consistently included steep slopes and factors associated with greater snow depth. Distribution of den locations shifted toward areas closer to human developments, indicating little negative influence of this factor on den-site selection by black bears in RMNP.

Presence of the vancomycin resistance gene cluster vanC1, vanXYc, and vanT in Enterococcus casseliflavus.

PubMed

Hölzel, Christina; Bauer, Johann; Stegherr, Eva-Maria; Schwaiger, Karin

2014-04-01

The three chromosomally located clustered genes vanC1, vanXYc, and vanT confer intrinsic resistance to vancomycin and are used for species identification of Enterococcus gallinarum. In this study, 28 strains belonging to the E. gallinarum/casseliflavus group isolated from cloacal swabs from laying hens were screened for the presence of vanC1. As confirmed by species-specific multiplex PCR, 11 vanC1-positive strains were identified as E. gallinarum. Surprisingly, one yellow pigmented strain, verified as E. casseliflavus by species-specific multiplex PCR, was also vanC1 positive; vanXYc and vanT were additionally detectable in this strain. To our knowledge, this is the first report of vanC1, vanXYc, and vanT in E. casseliflavus. The minimum inhibitory concentration of vancomycin was 4 mg/L. Real-time reverse transcription-PCR revealed that none of the clustered genes was expressed in this strain. Even if the genes seem not to be active, there is a certain risk that they will be transferred to other bacteria where they might be functionally expressed. Therefore, it may be advisable to expand the search for vanC1, vanXYc, and vanT from E. gallinarum to other (enterococcal) species. This study confirms that enterococci live up to their name as being reservoir bacteria and should therefore always be closely monitored.

Vector competence of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) for the DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus in Fujian, China.

PubMed

Guo, Xiao-Xia; Li, Chun-Xiao; Zhang, Ying-Mei; Xing, Dan; Dong, Yan-De; Zhang, Heng-Duan; Qin, Cheng-Feng; Zhao, Tong-Yan

2016-09-01

Dengue is an acute, emerging, infectious disease transmitted by Aedes mosquitoes that has become a serious global public health problem. The DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus were originally isolated from the serum of a patient with dengue fever in Fujian Province, China, in 1999. Our data provide the first assessment of the vector competence of Aedes mosquitoes with respect to the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus. There were significant differences in the replication rates of these two viral strains in Aedes albopictus and Aedes aegypti (P<0.05); replication of the DEN2-FJ10 strain was greater in Ae. aegypti than in Ae. albopictus 5 days post infection whereas replication of the DEN2-FJ11 was greater in Ae. albopictus than in Ae. aegypti 7 days post infection. The replicative ability of the DEN2-FJ11 strain was greater than that of the DEN2-FJ10 strain in infected Ae. albopictus. In infected Ae. aegypti, rapid proliferation of the DEN2-FJ10 strain occurred earlier than in the DEN2-FJ11 strain. There were no significant differences in the midgut and salivary gland infection rates of Ae. albopictus and Ae. aegypti with respect to either viral strain. Although the DEN2-FJ10 and DEN2-FJ11 strains differ in their virulence to neonatal rats, there was no significant difference in the ability of either Ae. albopictus or Ae. aegypti to transmit the DEN2-FJ10 and DEN2-FJ10 strains of the dengue 2 virus (P>0.05). In summary, our results indicate that Ae. albopictus and Ae. aegypti mosquitoes are moderately competent vectors of the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus and provide the first evidence of the effect of these two viral strains on the vector competence of mosquitoes in China. Copyright © 2016 Elsevier B.V. All rights reserved.

Post-den emergence behavior of polar bears (Ursus maritimus) in Northern Alaska

USGS Publications Warehouse

Smith, T.S.; Partridge, Steven T.; Amstrup, Steven C.; Schliebe, S.

2007-01-01

We observed polar bear (Ursus maritimus) maternity den sites on Alaska’s North Slope in March 2002 and 2003 in an effort to describe bears’ post-den emergence behavior. During 40 sessions spanning 459 h, we observed 8 adults and 14 dependent cubs outside dens for 37.5 h (8.2% of total observation time). There was no significant difference between den emergence dates in 2002 (mean = 15 Mar ± 4.1 d) and 2003 (mean = 21 Mar ± 2.1 d). Following initial den breakout, polar bears remained at their den sites for 1.5 to 14 days (mean = 8.1 ± 5.1 d). The average length of stay in dens between emergent periods was significantly shorter in 2002 (1.79 h) than in 2003 (4.82 h). While outside, adult bears were inactive 49.5% of the time, whereas cubs were inactive 13.4% of the time. We found no significant relationships between den emergence activity and weather. Adult polar bears at den sites subjected to industrial activity exhibited significantly fewer bouts of vigilance than denned bears in undisturbed areas (t = -5.5164, df = 4, p= 0.00). However, the duration of vigilance behaviors at sites near industrial activity was not significantly shorter than at the other sites studied (t = -1.8902, df = 4, p = 0.07). Results for these bears were within the range of findings in other studies of denned polar bears.

[Identification of Dens Draconis and Os Draconis by XRD method].

PubMed

Chen, Guang-Yun; Wu, Qi-Nan; Shen, Bei; Chen, Rong

2012-04-01

To establish an XRD method for evaluating the quality of Os Draconis and Dens Draconis and applying in judgement of the counterfeit. Dens Draconis, Os Draconis and the counterfeit of Os Draconis were analyzed by XRD. Their diffraction patterns were clustered analysis and evaluated their similarity degree. Established the analytical method of Dens Draconis and Os Draconis basing the features fingerprint information of the 10 common peaks by XRD pattern. Obtained the XRD pattern of the counterfeit of Os Draconis. The similarity degree of separate sources of Dens Draconis was high,while the similarity degree of separate sources of Os Draconis was significant different from each other. This method can be used for identification and evaluation of Os Draconis and Dens Draconis. It also can be used for identification the counterfeit of Os Draconis effectively.

Den use by arctic foxes (Alopex lagopus) in a subarctic region of western Alaska

USGS Publications Warehouse

Anthony, R. Michael

1996-01-01

Distribution, abundance, and use of arctic fox dens located in coastal tundra communities of the Yukon–Kuskokwim delta were determined in studies from 1985 to 1990. Dens were denser and less complex than those described in studies conducted above the Arctic Circle. Eighty-three dens of varying complexity were found in the 52-km2 study area. Nineteen dens were used by arctic foxes for whelping or rearing pups. Three females relocated litters to multiple dens; a maximum of four dens were used concurrently by pups from one litter. Although red foxes (Vulpes vulpes) were common in the region, their use of dens in the study area was minimal. Differences in vegetation at den sites and nearby unoccupied sites were minimal. Furthermore, den sites could not be distinguished from non-den sites during aerial surveys.

Despotism and risk of infanticide influence grizzly bear den-site selection.

PubMed

Libal, Nathan S; Belant, Jerrold L; Leopold, Bruce D; Wang, Guiming; Owen, Patricia A

2011-01-01

Given documented social dominance and intraspecific predation in bear populations, the ideal despotic distribution model and sex hypothesis of sexual segregation predict adult female grizzly bears (Ursus arctos) will avoid areas occupied by adult males to reduce risk of infanticide. Under ideal despotic distribution, juveniles should similarly avoid adult males to reduce predation risk. Den-site selection and use is an important component of grizzly bear ecology and may be influenced by multiple factors, including risk from conspecifics. To test the role of predation risk and the sex hypothesis of sexual segregation, we compared adult female (n = 142), adult male (n = 36), and juvenile (n = 35) den locations in Denali National Park and Preserve, Alaska, USA. We measured elevation, aspect, slope, and dominant land cover for each den site, and used maximum entropy modeling to determine which variables best predicted den sites. We identified the global model as the best-fitting model for adult female (area under curve (AUC) = 0.926) and elevation as the best predictive variable for adult male (AUC = 0.880) den sites. The model containing land cover and elevation best-predicted juvenile (AUC = 0.841) den sites. Adult females spatially segregated from adult males, with dens characterized by higher elevations (mean= 1,412 m, SE = 52) and steeper slopes (mean = 21.9°, SE = 1.1) than adult male (elevation: mean = 1,209 m, SE = 76; slope: mean = 15.6°, SE = 1.9) den sites. Juveniles used a broad range of landscape attributes but did not avoid adult male denning areas. Observed spatial segregation by adult females supports the sex hypothesis of sexual segregation and we suggest is a mechanism to reduce risk of infanticide. Den site selection of adult males is likely related to distribution of food resources during spring.

Polar bear maternal den habitat in the Arctic National Wildlife Refuge, Alaska

USGS Publications Warehouse

Durner, George M.; Amstrup, Steven C.; Ambrosius, Ken J.

2006-01-01

Polar bears (Ursus maritimus) give birth during mid-winter in dens of ice and snow. Denning polar bears subjected to human disturbances may abandon dens before their altricial young can survive the rigors of the Arctic winter. Because the Arctic coastal plain of Alaska is an area of high petroleum potential and contains existing and planned oil field developments, the distribution of polar bear dens on the plain is of interest to land managers. Therefore, as part of a study of denning habitats along the entire Arctic coast of Alaska, we examined high-resolution aerial photographs (n = 1655) of the 7994 km2 coastal plain included in the Arctic National Wildlife Refuge (ANWR) and mapped 3621 km of bank habitat suitable for denning by polar bears. Such habitats were distributed uniformly and comprised 0.29% (23.2 km2) of the coastal plain between the Canning River and the Canadian border. Ground-truth sampling suggested that we had correctly identified 91.5% of bank denning habitats on the ANWR coastal plain. Knowledge of the distribution of these habitats will help facilitate informed management of human activities and minimize disruption of polar bears in maternal dens.

Denning chronology and design of effective bear management units

USGS Publications Warehouse

Inman, R.M.; Costello, C.M.; Jones, D.E.; Inman, K.H.; Thompson, B.C.; Quigley, H.B.

2007-01-01

Reports on the effectiveness of using late fall hunting seasons to reduce the proportion of female black bears (Ursus americanus) in the harvest are limited, and the geographic scale over which the technique functions as intended has not been examined. During 1992-2000, we radio-equipped black bears in New Mexico, USA, obtained estimates of 175 den entry and 137 den emergence dates, and used New Mexico Department of Game and Fish harvest data (1985-2000) to test for differences in proportion of females in the harvest relative to denning chronology. Bears in northern New Mexico entered dens earlier and emerged later than bears in southern New Mexico (P ??? 0.001). In northern New Mexico bears displayed the typical pattern of earlier entry and later emergence by reproductive females, proportion of females in the harvest varied over time as expected, and late fall seasons were effective (P ??? 0.10). In contrast, denning chronology did not differ by sex in southern New Mexico, proportion of females in the harvest did not change over time, and late fall seasons were not effective (P ??? 0.18). Manipulation of hunting season dates to influence female mortality can be an effective tool, however our study provides an example of an area where denning chronology did not differ by sex and late seasons were not effective. We also observed regional differences in timing of entrance and emergence, which suggest that scale of application may be key. In management jurisdictions that encompass ecologically distinct areas, cover a wide range of latitudes, or are mountainous, successful use of the technique may depend on knowledge of denning chronology at multiple locations and appropriate designation of hunting unit boundaries, season dates, and data analysis units.

Den use and selection by northern flying squirrels in fragmented landscapes

Treesearch

Sanjay Pyare; Winston P. Smith; Colin S. Shanley

2010-01-01

We studied den use and den-habitat selection by the Prince of Wales Island flying squirrel (Glaucomys sabrinus griseifrons) at multiple spatial scales in fragmented temperate rain-forest habitats because of the role dens play in the distribution, reproduction, and population density of this endemic subspecies. We observed differences in spatial...

Genetics Home Reference: achromatopsia

MedlinePlus

... NW, Roosing S, van Schooneveld MJ, van Lith-Verhoeven JJ, van Moll-Ramirez N, van den Born LI, ... van Schooneveld MJ, Strom TM, van Lith-Verhoeven JJ, Lotery AJ, van Moll-Ramirez N, Leroy BP, ...

Patterns of den occupation by the spotted hyaena (Crocuta crocuta)

USGS Publications Warehouse

Boydston, E.E.; Kapheim, K.M.; Holekamp, K.E.

2006-01-01

Spotted hyaenas utilize isolated natal dens (NDs) and communal dens (CDs) for rearing their cubs. Here we describe patterns of natal and CD occupation by hyaenas belonging to one well-studied clan in the Maasai Mara National Reserve during a 10-year period. Locations of 98 den sites that were used as natal or CDs by hyaenas in the study clan were digitized in a Geographic Information System, and the duration of use of each den site, frequency of re-use, and distances involved in den moves were quantified. Hyaenas moved their CD monthly on average. Most CD sites were occupied only once during the study, but several sites were used repeatedly. On rare occasions, the movement of hyaenas to a new den site could be attributed to a disturbance event at the CD, but factors regularly prompting hyaenas to move to new CD sites were unclear. High-ranking female hyaenas were more likely to rear their cubs from birth in a CD than low-ranking females. Low-ranking females almost always utilized isolated NDs for the first few weeks of a litter's development, and low-ranking females transferred their cubs over longer distances than did high-ranking females. ?? 2006 East African Wild Life Society.

Developing an Effective and Efficient Real Time Strategy Agent for Use as a Computer Generated Force

DTIC Science & Technology

2010-03-01

Coello, Carlos A., Gary B. Lamont, and David A. Van Veldhuizen . Evolution- ary Algorithms for Solving Multi-Objective Problems (Genetic and...Practice. Oxford Univer- sity Press, 1996. 4. Bakkes, Sander, Philip Kerbusch, Pieter Spronck, and Jaap van den Herik. “Au- tomatically Evaluating...Pieter Spronck, and Jaap van den Herik. “Phase-dependent Evaluation in RTS games”. Proceedings of the 19th Belgian-Dutch Conference on Artificial

Raccoon (Procyon lotor) diurnal den use within an intensively managed forest in central West Virginia

USGS Publications Warehouse

Owen, Sheldon F.; Berl, Jacob L.; Edwards, John W.; Ford, W. Mark; Wood, Petra Bohall

2015-01-01

Intensive forest management may influence the availability of suitable den sites for large den-seeking species, such as Procyon lotor (Raccoon). As part of a Raccoon ecology study on an industrial forest in the Allegheny Mountains of central West Virginia, we radio-tracked 32 Raccoons to 175 diurnal den sites to determine relative use of dens that included cavity trees, rock dens, log piles, slash piles, and exposed limbs. Patterns of den use significantly differed between sexes and among seasons. Overall, we recorded 58 cavity dens in 12 tree species with 7 maternal dens found in 5 tree species. Raccoons selected larger-diameter den trees than available cavity trees and non-cavity trees. Because the abundance of suitable tree cavities is known to influence Raccoon densities and recruitment at fine spatial scales and female Raccoons in this study used tree cavities as maternal den sites, the continued harvest of large-diameter trees (i.e., those capable of developing den cavities) without replacement may impact Raccoon recruitment within intensively managed forests throughout the central Appalachians.

Identification of polar bear den habitat in northern Alaska

USGS Publications Warehouse

Amstrup, Steven C.; Garner, Gerald W.; Derocher, Andrew E.; Garner, Gerald W.; Lunn, Nicholas J.; Wiig, Øystein; Derocher, Andrew E.; Garner, Gerald W.; Lunn, Nicholas J.; Wiig, Øystein

1998-01-01

The goal of this project is to refine the information collected previously on maternal denning, into digital maps that show where polar bears are likely to create future dens in northern Alaska. Such maps will allow a priori recommendations regarding timing and geographic locations of proposed human developments; and hence provide managers with an important mitigation and management tool.

Biomechanics of halo-vest and dens screw fixation for type II odontoid fracture.

PubMed

Ivancic, Paul C; Beauchman, Naseem N; Mo, Fred; Lawrence, Brandon D

2009-03-01

An in vitro biomechanical study of halo-vest and odontoid screw fixation of Type II dens fracture. The objective were to determine upper cervical spine instability due to simulated dens fracture and investigate stability provided by the halo-vest and odontoid screw, applied individually and combined. Previous studies have evaluated posterior fixation techniques for stabilizing dens fracture. No previous biomechanical study has investigated the halo-vest and odontoid screw for stabilizing dens fracture. A biofidelic skull-neck-thorax model was used with 5 osteoligamentous whole cervical spine specimens. Three-dimensional flexibility tests were performed on the specimens while intact, following simulated dens fracture, and following application of the halo-vest alone, odontoid screw alone, and halo-vest and screw combined. Average total neutral zone and total ranges of motion at C0/1 and C1/2 were computed for each experimental condition and statistically compared with physiologic motion limits, obtained from the intact flexibility test. Significance was set at P < 0.05 with a trend toward significance at P < 0.1. Type II dens fracture caused trends toward increased sagittal neutral zone and lateral bending range of motion at C1/2. Spinal motions with the dens screw alone could not be differentiated from physiologic limits. Significant reductions in motion were observed at C0/1 and C1/2 in flexion-extension and axial rotation due to the halo-vest, applied individually or combined with the dens screw. At C1/2, the halo-vest combined with the dens screw generally allowed the smallest average percentages of intact motion: 3% in axial rotation, 17% in flexion-extension, and 18% in lateral bending. The present reduction in C1/2 motion observed, due to the halo-vest and dens screw combined is similar to previously reported immobilization provided by the polyaxial screw/rod system and transarticular screw fixation combined with wiring. The present biomechanical data may be

Geographical Information Extraction With Remote Sensing. Part I - Main Report.

DTIC Science & Technology

1998-08-01

Oude Waalsdorperweg 63 Date P0 Box 96864 2509 JG The Hague August 1998 The Netherlands Author(s) Phone +31 70 374 00 00 Dr A.C. van den Broek Fax +31 70...328 09 61 M. van Persie H.H.S. Noorbergen Dr G.J. Rijckenberg SSponsor HWO-COfHWO-KL N E R Project officer J. Rogge Affiliation KIN/IA - i All...Main report Auteur(s) Dr. A.C. van den Broek, Ir. M. van Persie, Ing. H.H.S. Noorberg~en, Dr. G.J. Rijkenberg Datum augustus 1998 Opdrachtnr

Landward and eastward shift of Alaskan polar bear denning associated with recent sea ice changes

USGS Publications Warehouse

Fischbach, Anthony S.; Amstrup, Steven C.; Douglas, David C.

2007-01-01

Polar bears (Ursus maritimus) in the northern Alaska region den in coastal areas and on offshore drifting ice. We evaluated changes in the distribution of polar bear maternal dens between 1985 and 2005, using satellite telemetry. We determined the distribution of maternal dens occupied by 89 satellite collared female polar bears between 137°W and 167°W longitude. The proportion of dens on pack ice declined from 62% in 1985–1994 to 37% in 1998–2004 (P = 0.044) and among pack ice dens fewer occurred in the western Beaufort Sea after 1998. We evaluated whether hunting, attraction to bowhead whale remains, or changes in sea ice could explain changes in den distribution. We concluded that denning distribution changed in response to reductions in stable old ice, increases in unconsolidated ice, and lengthening of the melt season. In consort, these changes have likely reduced the availability and quality of pack ice denning habitat. Further declines in sea ice availability are predicted. Therefore, we expect the proportion of polar bears denning in coastal areas will continue to increase, until such time as the autumn ice retreats far enough from shore that it precludes offshore pregnant females from reaching the Alaska coast in advance of denning.

Hydrodynamics of the VanA-type VanS histidine kinase: an extended solution conformation and first evidence for interactions with vancomycin

PubMed Central

Phillips-Jones, Mary K.; Channell, Guy; Kelsall, Claire J.; Hughes, Charlotte S.; Ashcroft, Alison E.; Patching, Simon G.; Dinu, Vlad; Gillis, Richard B.; Adams, Gary G.; Harding, Stephen E.

2017-01-01

VanA-type resistance to glycopeptide antibiotics in clinical enterococci is regulated by the VanSARA two-component signal transduction system. The nature of the molecular ligand that is recognised by the VanSA sensory component has not hitherto been identified. Here we employ purified, intact and active VanSA membrane protein (henceforth referred to as VanS) in analytical ultracentrifugation experiments to study VanS oligomeric state and conformation in the absence and presence of vancomycin. A combination of sedimentation velocity and sedimentation equilibrium in the analytical ultracentrifuge (SEDFIT, SEDFIT-MSTAR and MULTISIG analysis) showed that VanS in the absence of the ligand is almost entirely monomeric (molar mass M = 45.7 kDa) in dilute aqueous solution with a trace amount of high molar mass material (M ~ 200 kDa). The sedimentation coefficient s suggests the monomer adopts an extended conformation in aqueous solution with an equivalent aspect ratio of ~(12 ± 2). In the presence of vancomycin over a 33% increase in the sedimentation coefficient is observed with the appearance of additional higher s components, demonstrating an interaction, an observation consistent with our circular dichroism measurements. The two possible causes of this increase in s – either a ligand induced dimerization and/or compaction of the monomer are considered. PMID:28397853

Fox Den Disease: An Interesting Case Following Delayed Diagnosis.

PubMed

Stehr, Ryan C; Kim, Nicholas; LoGiudice, John A; Ludwig, Kirk

2015-06-01

Pyoderma fistulans sinifica, also known as fox den disease, is a rare and poorly understood inflammatory disorder of the skin and subcutaneous tissues. This disorder is often mistaken for other inflammatory skin disorders and treated inappropriately. The authors describe the case of a 53-year-old male who presented to the colorectal surgery service with a longstanding diagnosis of perirectal Crohn's disease. Despite aggressive immunosuppression and numerous surgical procedures, the patient continued to have unrelenting purulent drainage from the skin of his buttocks. Following wide excision of the affected skin and subcutaneous tissues by the colorectal surgeon, the plastic surgery team reconstructed the 30 cm x 55 cm wound using a combination of local flaps and skin grafts. The initial pathology report of the excised specimen confirmed the presence of nonspecific abscesses and inflammation. Upon special request by the plastic surgery team, the sample was resectioned with the specific intent of establishing a diagnosis of fox den disease. The additional slides met the criteria for an unequivocal diagnosis of fox den disease. Immunosuppression was discontinued and the patient healed his wounds without complication. Fox den disease is often overlooked because of the obscurity of the disease and the special histological sectioning needed to establish a diagnosis. In this case, the patient was unnecessarily treated with immunosuppressive drugs for more than 3 decades because of a misdiagnosis. With increased awareness of fox den disease, perhaps its pathophysiology can be better elucidated as more patients are appropriately diagnosed and treated.

Endodontic, surgical and periodontal treatment of dens invaginatus. Case report.

PubMed

Castellarin, M; Demitri, V; Politi, M

2001-01-01

The aim of this paper is to propose a single stage global treatment of endodontic, periapical and periodontal lesions in a lateral maxillary incisor with dens invaginatus. A 24 year-old woman presenting a lateral maxillary incisor with dens invaginatus in association with periapica1 and periodontal lesions underwent simultaneous surgical, endodontic and periodontal regenerative procedures. At 2, 6, 12, 18 months follow-up the radiographic healing appeared to be improved and the periapical lesion healed completely 1 year after surgical intervention. Surgery in association with endodontic and periodontal procedures represents the treatment of choice to maximize long term prognosis in cases of dens invaginatus with chronic periapical and periodontal lesions.

Vegetative characteristics of swift fox denning and foraging sites in southwestern South Dakota

Treesearch

Daniel W. Uresk; Kieth E. Severson; Jody Javersak

2003-01-01

Vegetative characteristics of swift fox (Vulpes velox) denning and foraging habitats were studied in southwestern South Dakota. We followed 14 radio-collared foxes over a two-year period and identified 17 den sites and 82 foraging sites. Height-density of vegetation (visual obstruction reading, VOR) was determined on each den and foraging site and on...

Dragons' Den: promoting healthcare research and innovation.

PubMed

Mazhindu, Deborah; Gregory, Siobhan

2015-07-01

The changing health and social care landscape, and, in particular, the financial challenges affecting the NHS, can present difficulties for staff looking for funding to support innovation and new ways of working. One method of competitive tendering that is becoming more accepted as a way of allocating funds, encouraging staff engagement and developing innovation for research is a format based the BBC television series, Dragons' Den. This article describes how Hounslow and Richmond Community Healthcare NHS Trust, London, has developed a 'Dragons' Den initiative' of annual competitive research funding allocation to ensure that some of the most dynamic practice in the trust is captured.

Co-colonization of vanA and vanB Enterococcus faecium of clonal complex 17 in a patient with bacteremia due to vanA E. faecium.

PubMed

Seol, Chang Ahn; Park, Jeong Su; Sung, Heungsup; Kim, Mi-Na

2014-06-01

A 53-year-old Vietnamese man with liver cirrhosis was transferred from a Vietnamese hospital to our tertiary care hospital in Korea in order to undergo a liver transplantation. Bacteremia due to vanA Enterococcus faecium was diagnosed, and stool surveillance cultures for vancomycin-resistant enterococci (VRE) were positive for both vanA and vanB E. faecium. Pulsed-field gel electrophoresis analysis revealed that the 2 vanA VRE isolates from the blood and stool were clonal, but the vanB VRE was unrelated to the vanA VRE. vanA and vanB VRE were ST64 and ST18, single-allele variations of clonal complex 17, respectively. This is the first case report of vanA VRE bacteremia in a Vietnamese patient and demonstrates the reemergence of vanB VRE since a single outbreak occurred 15years ago in Korea. The reemergence of vanB VRE emphasizes the importance of VRE genotyping to prevent the spread of new VRE strains. Copyright © 2014 Elsevier Inc. All rights reserved.

Dens invaginatus in primary maxillary molar: a rare case report and review of literature.

PubMed

Bansal, Arpana V; Bansal, Abhinav; Kulkarni, Vinaya Kumar; Dhar, Reema Sharma

2012-05-01

Dens invaginatus is a rare developmental anomaly. It is unusual to find this anomaly in primary dentition. Diagnosis of this dens invaginatus is important due to possible pulpal involvement. Not only that, simultaneous presence of other dental anomaly may require long-term treatment planning. Dens invaginatus can be detected clinically in the tooth presenting unusual crown morphology or radiographically as radiopacity within tooth. This article describes one of the first case reports of dens invaginatus in primary maxillary second molar in a 5-year-old female patient. How to cite this article: Bansal AV, Bansal A, Kulkarni VK, Dhar RS. Dens Invaginatus in Primary Maxillary Molar: A Rare Case Report and Review of Literature. Int J Clin Pediatr Dent 2012;5(2):139-141.

View east along Wolf Den Road showing residences on the ...

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

View east along Wolf Den Road showing residences on the north side of the road - Brooklyn Green, North Green, South Green, & West Green, parts of Brown Road, Canterbury Road (Route 169), Hartford Road (Route 6), Hyde Road, Pomfret Road (Route 169), Prince Hill Road, Providence Road (Route 6), Wauregan Road (Routes 169 & 205), & Wolf Den Road, Brooklyn, Windham County, CT

View northwest along Wolf Den Road showing residences on the ...

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

View northwest along Wolf Den Road showing residences on the north side of the road - Brooklyn Green, North Green, South Green, & West Green, parts of Brown Road, Canterbury Road (Route 169), Hartford Road (Route 6), Hyde Road, Pomfret Road (Route 169), Prince Hill Road, Providence Road (Route 6), Wauregan Road (Routes 169 & 205), & Wolf Den Road, Brooklyn, Windham County, CT

Den site activity patterns of adult male and female swift foxes, Vulpes velox, in Northwestern Texas

USGS Publications Warehouse

Lemons, P.R.; Ballard, W.B.; Sullivan, R.M.; Sovada, M.A.

2003-01-01

Activity of Swift Foxes (Vulpes velox) at den sites was studied in northwestern Texas during pup rearing seasons in 2000 and 2001 to determine role of males in parental care. Twenty-four percent of radio-collared females with a potential to breed successfully raised pups to eight weeks of age. We intensively monitored presence and absence of male and female Swift Foxes at two den sites each year. Females were present >2.6 times more at den sites than males during the pup rearing season. Female and male Swift Foxes largely stayed at dens during diurnal hours and were active away from dens during nocturnal and crepuscular hours. Females and males spent 12.4% and 3.0% more time at dens before pups emerged, than after pups emerged, respectively. Following depredation of one male parent, the female spent 29% less time at the den site. Decrease in time spent at the den by the female following loss of her mate suggested that loss of one parent might severely impact recruitment of Swift Foxes. Our observations indicated that intense Coyote (Canis latrans) depredation may severely impact pup-rearing success as well as the parental care within Swift Fox family groups.

Amino acid substitutions in the VanS sensor of the VanA-type vancomycin-resistant Enterococcus strains result in high-level vancomycin resistance and low-level teicoplanin resistance.

PubMed

Hashimoto, Y; Tanimoto, K; Ozawa, Y; Murata, T; Ike, Y

2000-04-15

The vancomycin-resistant enterococci GV1, GV2 and GV3, which were isolated from droppings from broiler farms in Japan have been characterized as VanA-type VRE, which express high-level vancomycin resistance (256 or 512 microg ml(-1), MIC) and low-level teicoplanin resistance (1 or 2 microg ml(-1), MIC). The vancomycin resistances were encoded on plasmids. The vancomycin resistance conjugative plasmid pMG2 was isolated from the GV2 strain. The VanA determinant of pMG2 showed the same genetic organization as that of the VanA genes encoded on the representative transposon Tn1546, which comprises vanRSHAXYZ. The nucleotide sequences of all the genes, except the gene related to the vanS gene on Tn1546, were completely identical to the genes encoded on Tn1546. Three amino acid substitutions in the N-terminal region of the deduced VanS were detected in the nucleotide sequence of vanS encoded on pMG2. There were also three amino acid substitutions in the vanS gene of the GV1 and GV3 strains in the same positions as in the vanS gene of pMG2. Vancomycin induced the increased teicoplanin resistance in these strains.

[Dens invaginatus. Review of the literature and diagnostic and therapeutic guidelines].

PubMed

Baumgart, Manuela; Hänni, Stefan; Suter, Beat; Schaffner, Markus; Lussi, Adrian

2009-01-01

Dens invaginatus is a clinically relevant malformation of teeth resulting from an infolding of enamel and dentine into the dental structure during tooth formation, hence the former denomination "dens in dente". The dens invaginatus shows multiple morphological variations of crown and root formation. This frequently leads to caries, pulpal and periodontal involvement with necrosis and loss of attachment. Therefore, early diagnosis and prevention are of utmost importance. Due to the complexity of the malformation, treatment options in former days were limited. This article presents a profound review of the literature regarding etiology, epidemiology and histology. It discusses clinical appearance and diagnosis and it provides guidelines for decision-making and treatment of invaginated teeth.

Euthanasia for Detainees in Belgium.

PubMed

Devolder, Katrien

2016-07-01

In 2011, Frank Van Den Bleeken became the first detainee to request euthanasia under Belgium's Euthanasia Act of 2002. This article investigates whether it would be lawful and morally permissible for a doctor to accede to this request. Though Van Den Bleeken has not been held accountable for the crimes he committed, he has been detained in an ordinary prison, without appropriate psychiatric care, for more than 30 years. It is first established that Van Den Bleeken's euthanasia request plausibly meets the relevant conditions of the Euthanasia Act and that, consequently, a doctor could lawfully fulfill it. Next, it is argued that autonomy-based reasons for euthanizing him outweigh complicity-based reasons against doing so, and that, therefore, it is also morally permissible for a doctor to carry out the euthanasia request.

19 CFR 10.41a - Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international...

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 1 2011-04-01 2011-04-01 false Lift vans, cargo vans, shipping tanks, skids... Traffic § 10.41a Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international traffic; repair components. (a)(1) Lift vans, cargo vans, shipping tanks, skids, pallets, caul...

19 CFR 10.41a - Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Lift vans, cargo vans, shipping tanks, skids... Traffic § 10.41a Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international traffic; repair components. (a)(1) Lift vans, cargo vans, shipping tanks, skids, pallets, caul...

Atypical den use of Carolina Northern Flying Squirrels (Glaucomys sabrinus coloratus) in the southern Appalachian Mountains

USGS Publications Warehouse

Diggins, Corinne A.; Kelly, Christine A.; Ford, W. Mark

2015-01-01

Glaucomys sabrinus coloratus (Carolina Northern Flying Squirrel) is a federally endangered subspecies that occurs in high elevation forests of the southern Appalachian Mountains. Denning sites may be a limiting factor for this subspecies in areas where cavity trees are not abundant or where interspecific competition from other tree squirrels occurs. This shortage can result in use of unusual denning sites, such as subterranean dens. Herein, we report atypical denning habits of radio-collared Carolina Northern Flying Squirrels in southwestern Virginia and western North Carolina from 2008 to 2011 and 2014. Increased knowledge of denning habitats may be beneficial for conservation and habitat management of this subspecies, particularly in sub-optimal or degraded habitats.

Defending commercial surrogate motherhood against Van Niekerk and Van Zyl.

PubMed Central

McLachlan, H V

1997-01-01

The arguments of Van Niekerk and Van Zyl that, on the grounds that it involves an inappropriate commodification and alienation of women's labour, commercial surrogate motherhood (CSM) is morally suspect are discussed and considered to be defective. In addition, doubt is cast on the notion that CSM should be illegal. PMID:9451602

Hibernacula and summer den sites of pine snakes (Pituophis melanoleucus) in the New Jersey pine barrens

USGS Publications Warehouse

Burger, J.; Zappalorti, R.T.; Gochfeld, M.; Boarman, W.I.; Caffrey, M.; Doig, V.; Garber, S.D.; Lauro, B.; Mikovsky, M.; Safina, C.; Saliva, Jorge

1988-01-01

We examined eight summer dens (used only in summer) and seven hibernacula (occupied both in winter and summer) of the snake Pituophis melanoleucus in the New Jersey Pine Barrens, comparing above ground characteristics of hibernacula and summer dens with characteristics at nearby random points. Temperatures at the soil surface and at 10 cm depth were significantly warmer, and there was less leaf cover around the random points compared to the entrances of the hibernacula and summer dens. Hibernacula had significantly more vegetation cover within 5 m, more leaf cover over the burrow entrance, and were closer to trees than were summer dens. Most hibernacula and summer dens were beside old fallen logs (73%), the entrance tunnels following decaying roots into the soil. Excavation of the hibernacula and summer dens indicated that most hibernacula appeared to be dug by the snakes and had an average of eight side chambers and 642 cm of tunnels, compared to less than one side chamber and 122 cm of tunnels for summer dens. Except for hatchlings, most snakes in hibernacula were located in individual chambers off the main tunnel; all snakes were at depths of 50-111 cm (X̄ = 79 cm). Pine snakes may select optimum hibernation sites which reduce winter mortality.

Space Van system update

NASA Astrophysics Data System (ADS)

Cormier, Len

1992-07-01

The Space Van is a proposed commercial launch vehicle that is designed to carry 1150 kg to a space-station orbit for a price of $1,900,000 per flight in 1992 dollars. This price includes return on preoperational investment. Recurring costs are expected to be about $840,000 per flight. The Space Van is a fully reusable, assisted-single-stage-to orbit system. The most innovative new feature of the Space Van system is the assist-stage concept. The assist stage uses only airbreathing engines for vertical takeoff and vertical landing in the horizontal attitude and for launching the rocket-powered orbiter stage at mach 0.8 and an altitude of about 12 km. The primary version of the orbiter is designed for cargo-only without a crew. However, a passenger version of the Space Van should be able to carry a crew of two plus six passengers to a space-station orbit. Since the Space Van is nearly single-stage, performance to polar orbit drops off significantly. The cargo version should be capable of carrying 350 kg to a 400-km polar orbit. In the passenger version, the Space Van should be able to carry two crew members - or one crew member plus a passenger.

Collar temperature sensor data reveal long-term patterns in southern Beaufort Sea polar bear den distribution on pack ice and land

USGS Publications Warehouse

Olson, Jay W; Rode, Karyn D.; Eggett, Dennis L.; Smith, T.S.; Wilson, R. R.; Durner, George M.; Fischbach, Anthony S.; Atwood, Todd C.; Douglas, David C.

2017-01-01

In response to a changing climate, many species alter habitat use. Polar bears Ursus maritimus in the southern Beaufort Sea have increasingly used land for maternal denning. To aid in detecting denning behavior, we developed an objective method to identify polar bear denning events using temperature sensor data collected by satellite-linked transmitters deployed on adult females between 1985 and 2013. We then applied this method to determine whether southern Beaufort Sea polar bears have continued to increase land denning with recent sea-ice loss and examined whether sea-ice conditions affect the distribution of dens between pack-ice and coastal substrates. Because land use in summer and autumn has also increased, we examined potential associations between summering substrate and denning substrate. Statistical process control methods applied to temperature-sensor data identified denning events with 94.5% accuracy in comparison to direct observations (n = 73) and 95.7% accuracy relative to subjective classifications based on temperature, location, and activity sensor data (n = 116). We found an increase in land-based denning during the study period. The frequency of land denning was directly related to the distance that sea ice retreated from the coast. Among females that denned, all 14 that summered on land subsequently denned there, whereas 29% of the 69 bears summering on ice denned on land. These results suggest that denning on land may continue to increase with further loss of sea ice. While the effects that den substrate have on nutrition, energetics, and reproduction are unclear, more polar bears denning onshore will likely increase human-bear interactions.

Remote identification of maternal polar bear (Ursus maritimus) denning habitat on the Colville River Delta, Alaska

NASA Astrophysics Data System (ADS)

Blank, Justin J.

High resolution digital aerial photographs (1 foot pixel size) of the Colville River Delta, Alaska were examined in 3D, with the use of a digital photogrammetric workstation. Topographic features meeting the criteria required for adequate snow accumulation, and subsequent construction of terrestrial polar bear maternal dens, were identified and digitized into an ArcGIS line shapefile. Effectiveness, efficiency, and accuracy were improved when compared to previous polar bear denning habitat efforts which utilized contact photo prints and a pocket stereoscope in other geographic areas of northern Alaska. Accuracy of photograph interpretation was systematically evaluated visually from the air with the use of a helicopter and physically on the ground. Results show that the mapping efforts were successful in identifying den habitat 91.3% of the time. Knowledge denning habitat can improve and inform decision making by managers and regulators when considering travel and development in the study area. An understanding of polar bear denning habitat extent and location will be a crucial tool for planning activities within the study area in a way that minimizes conflicts with maternal dens.

A mid-holocene fauna from Bear Den Cave, Sequoia National Park, California

USGS Publications Warehouse

Mead, Jim I.; McGinnis, Thomas W.; Keeley, Jon E.

2006-01-01

Test excavation of floor fill deposits in the first room in Bear Den Cave, Sequoia National Park, produced fossiliferous sediments down to at least 40 cm depth. Radiocarbon analysis of charcoal from this layer indicates an early-middle Holocene age of 7220 CAL BP. The fossil accumulation represents prey recovered from generations of ringtail (Bassariscus astutus) dung. Microvertebrate remains include salamanders, lizards, snakes, and mammals. The recovery of Aneides ferreus/vagransfrom early-middle Holocene deposits in Bear Den Cave is a first for this species group. Equally interesting is the recovery of Plethodon sp. Neither taxa live in the Sierra Nevada today. The fossil-rich deposits of Bear Den Cave indicate that future paleoecological studies will be productive in Sequoia National Park.

Heading for the Hills: Risk Avoidance Drives Den Site Selection in African Wild Dogs

PubMed Central

Jackson, Craig R.; Power, R. John; Groom, Rosemary J.; Masenga, Emmanuel H.; Mjingo, Ernest E.; Fyumagwa, Robert D.; Røskaft, Eivin; Davies-Mostert, Harriet

2014-01-01

Compared to their main competitors, African wild dogs (Lycaon pictus) have inferior competitive abilities and interspecific competition is a serious fitness-limiting factor. Lions (Panthera leo) are the dominant large carnivore in African savannah ecosystems and wild dogs avoid them both spatially and temporally. Wild dog young are particularly vulnerable and suffer high rates of mortality from lions. Since lions do not utilize all parts of the landscape with an equal intensity, spatial variation in lion densities can be exploited by wild dogs both during their general ranging behaviour, but more specifically when they are confined to a den with vulnerable young. Since patches of rugged terrain are associated with lower lion densities, we hypothesized that these comparatively safe habitats should be selected by wild dogs for denning. We investigated the relationship between the distribution of 100 wild dog den sites and the occurrence of rugged terrain in four wild dog populations located in Tanzania, Zimbabwe and South Africa. A terrain ruggedness index was derived from a 90 m digital elevation model and used to map terrain ruggedness at each site. We compared characteristics of actual and potential (random) den sites to determine how wild dogs select den sites. The distributions of wild dog dens were strongly associated with rugged terrain and wild dogs actively selected terrain that was more rugged than that available on average. The likelihood of encountering lions is reduced in these habitats, minimizing the risk to both adults and pups. Our findings have important implications for the conservation management of the species, especially when assessing habitat suitability for potential reintroductions. The simple technique used to assess terrain ruggedness may be useful to investigate habitat suitability, and even predict highly suitable denning areas, across large landscapes. PMID:24918935

Heading for the hills: risk avoidance drives den site selection in African wild dogs.

PubMed

Jackson, Craig R; Power, R John; Groom, Rosemary J; Masenga, Emmanuel H; Mjingo, Ernest E; Fyumagwa, Robert D; Røskaft, Eivin; Davies-Mostert, Harriet

2014-01-01

Compared to their main competitors, African wild dogs (Lycaon pictus) have inferior competitive abilities and interspecific competition is a serious fitness-limiting factor. Lions (Panthera leo) are the dominant large carnivore in African savannah ecosystems and wild dogs avoid them both spatially and temporally. Wild dog young are particularly vulnerable and suffer high rates of mortality from lions. Since lions do not utilize all parts of the landscape with an equal intensity, spatial variation in lion densities can be exploited by wild dogs both during their general ranging behaviour, but more specifically when they are confined to a den with vulnerable young. Since patches of rugged terrain are associated with lower lion densities, we hypothesized that these comparatively safe habitats should be selected by wild dogs for denning. We investigated the relationship between the distribution of 100 wild dog den sites and the occurrence of rugged terrain in four wild dog populations located in Tanzania, Zimbabwe and South Africa. A terrain ruggedness index was derived from a 90 m digital elevation model and used to map terrain ruggedness at each site. We compared characteristics of actual and potential (random) den sites to determine how wild dogs select den sites. The distributions of wild dog dens were strongly associated with rugged terrain and wild dogs actively selected terrain that was more rugged than that available on average. The likelihood of encountering lions is reduced in these habitats, minimizing the risk to both adults and pups. Our findings have important implications for the conservation management of the species, especially when assessing habitat suitability for potential reintroductions. The simple technique used to assess terrain ruggedness may be useful to investigate habitat suitability, and even predict highly suitable denning areas, across large landscapes.

Mapping polar bear maternal denning habitat in the National Petroleum Reserve -- Alaska with an IfSAR digital terrain model

USGS Publications Warehouse

Durner, George M.; Simac, Kristin S.; Amstrup, Steven C.

2013-01-01

The National Petroleum Reserve–Alaska (NPR-A) in northeastern Alaska provides winter maternal denning habitat for polar bears (Ursus maritimus) and also has high potential for recoverable hydrocarbons. Denning polar bears exposed to human activities may abandon their dens before their young are able to survive the severity of Arctic winter weather. To ensure that wintertime petroleum activities do not threaten polar bears, managers need to know the distribution of landscape features in which maternal dens are likely to occur. Here, we present a map of potential denning habitat within the NPR-A. We used a fine-grain digital elevation model derived from Interferometric Synthetic Aperture Radar (IfSAR) to generate a map of putative denning habitat. We then tested the map’s ability to identify polar bear denning habitat on the landscape. Our final map correctly identified 82% of denning habitat estimated to be within the NPR-A. Mapped denning habitat comprised 19.7 km2 (0.1% of the study area) and was widely dispersed. Though mapping denning habitat with IfSAR data was as effective as mapping with the photogrammetric methods used for other regions of the Alaskan Arctic coastal plain, the use of GIS to analyze IfSAR data allowed greater objectivity and flexibility with less manual labor. Analytical advantages and performance equivalent to that of manual cartographic methods suggest that the use of IfSAR data to identify polar bear maternal denning habitat is a better management tool in the NPR-A and wherever such data may be available.

Mentale Inzetbaarheid van Teams: Ontwikkeling van een Moden van Teamfunctioneren als Module voor SCOPE (Mental Readiness of Teams - Development of a Team Model as Module for SCOPE)

DTIC Science & Technology

2007-04-01

inzetbaarheid van teams: ontwikkeling van een model van teamfunctioneren als module voor SCOPE Datumn april 2007 Auteur (s) R. de B~ruin C’. Vervvijs A.J...Datum april 2007 Programmaleider Projectleider Auteur (s) dr. W.A. Lotens, TNO Defensie en A.]. van Vijet, TNO Defensie en R. de Bruin Veiligheid...Deelnemers verwachten wel, in lijn met de theorie , dat een lage cohesie samenhangt met een lage effectiviteit. Een hoge cohesie, daarentegen, zou

Mobile Telemetry Van Remote Control Upgrade

DTIC Science & Technology

2012-05-17

Advantages of Remote Control System Upgrade • Summary Overview • Remote control of Telemetry Mobile Ground Support ( TMGS ) Van proposed to allow...NWC) personnel provided valuable data for full-function remote control of telemetry tracking vans Background • TMGS Vans support Flight Test...control capability from main TM site at Building 5790 currently allows support via TMGS Van at nearby C- 15 Site, Plant 42 in Palmdale, and as far

Members of the Genera Paenibacillus and Rhodococcus Harbor Genes Homologous to Enterococcal Glycopeptide Resistance Genes vanA and vanB

PubMed Central

Guardabassi, L.; Christensen, H.; Hasman, H.; Dalsgaard, A.

2004-01-01

Genes homologous to enterococcal glycopeptide resistance genes vanA and vanB were found in glycopeptide-resistant Paenibacillus and Rhodococcus strains from soil. The putative d-Ala:d-Lac ligase genes in Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B were closely related to vanA (92 and 87%) and flanked by genes homologous to vanH and vanX in vanA operons. PMID:15561881

Members of the genera Paenibacillus and Rhodococcus harbor genes homologous to enterococcal glycopeptide resistance genes vanA and vanB.

PubMed

Guardabassi, L; Christensen, H; Hasman, H; Dalsgaard, A

2004-12-01

Genes homologous to enterococcal glycopeptide resistance genes vanA and vanB were found in glycopeptide-resistant Paenibacillus and Rhodococcus strains from soil. The putative D-Ala:D-Lac ligase genes in Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B were closely related to vanA (92 and 87%) and flanked by genes homologous to vanH and vanX in vanA operons.

19 CFR 10.41a - Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international...

Code of Federal Regulations, 2014 CFR

2014-04-01

... for inspection by Customs officials upon reasonable notice. (3) If the container does not exit the U.S... 19 Customs Duties 1 2014-04-01 2014-04-01 false Lift vans, cargo vans, shipping tanks, skids... Traffic § 10.41a Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of...

19 CFR 10.41a - Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international...

Code of Federal Regulations, 2012 CFR

2012-04-01

... for inspection by Customs officials upon reasonable notice. (3) If the container does not exit the U.S... 19 Customs Duties 1 2012-04-01 2012-04-01 false Lift vans, cargo vans, shipping tanks, skids... Traffic § 10.41a Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of...

19 CFR 10.41a - Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of international...

Code of Federal Regulations, 2013 CFR

2013-04-01

... for inspection by Customs officials upon reasonable notice. (3) If the container does not exit the U.S... 19 Customs Duties 1 2013-04-01 2013-04-01 false Lift vans, cargo vans, shipping tanks, skids... Traffic § 10.41a Lift vans, cargo vans, shipping tanks, skids, pallets, and similar instruments of...

Genetics Home Reference: Wagner syndrome

MedlinePlus

... which the part of the retina responsible for sharp central vision is out of place. Additionally, the ... Brouwer AP, van Nouhuys CE, Boon CJ, Perveen R, Zegers HA, Wittebol-Post D, van den Biesen ...

Job Oriented Training Handleiding voor Luchtdoelartillerie (Job Oriented Training: Instructors Manual Air Defense)

DTIC Science & Technology

2008-11-01

luchtdoelartillerie Kampweg 5 Postbus 23 3769 ZG Soesterberg www.tno.nl T +31 346 35 62 11 F +31 346 35 39 77 lnfo-DenV@tno.nl Datum Auteur (s...een hoger begripsniveau getild. Theorie wordt niet van te voren aangeboden door middel van kennisover- dracht, maar wordt gaandeweg opgedaan. De...346 35 39 77 lnfo-DenV@tno.nl TNO-rapportnummer TNO-DV 2008 A394 Opdrachtnummer 851.2116.0152.11 Datum november 2008 Auteur (s) ir. T.J

Arctic foxes as ecosystem engineers: increased soil nutrients lead to increased plant productivity on fox dens

NASA Astrophysics Data System (ADS)

Gharajehdaghipour, Tazarve; Roth, James D.; Fafard, Paul M.; Markham, John H.

2016-04-01

Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ15N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra.

Arctic foxes as ecosystem engineers: increased soil nutrients lead to increased plant productivity on fox dens

PubMed Central

Gharajehdaghipour, Tazarve; Roth, James D.; Fafard, Paul M.; Markham, John H.

2016-01-01

Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ15N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra. PMID:27045973

Arctic foxes as ecosystem engineers: increased soil nutrients lead to increased plant productivity on fox dens.

PubMed

Gharajehdaghipour, Tazarve; Roth, James D; Fafard, Paul M; Markham, John H

2016-04-05

Top predators can provide fundamental ecosystem services such as nutrient cycling, and their impact can be even greater in environments with low nutrients and productivity, such as Arctic tundra. We estimated the effects of Arctic fox (Vulpes lagopus) denning on soil nutrient dynamics and vegetation production near Churchill, Manitoba in June and August 2014. Soils from fox dens contained higher nutrient levels in June (71% more inorganic nitrogen, 1195% more extractable phosphorous) and in August (242% more inorganic nitrogen, 191% more extractable phosphorous) than adjacent control sites. Inorganic nitrogen levels decreased from June to August on both dens and controls, whereas extractable phosphorous increased. Pup production the previous year, which should enhance nutrient deposition (from urine, feces, and decomposing prey), did not affect soil nutrient concentrations, suggesting the impact of Arctic foxes persists >1 year. Dens supported 2.8 times greater vegetation biomass in August, but δ(15)N values in sea lyme grass (Leymus mollis) were unaffected by denning. By concentrating nutrients on dens Arctic foxes enhance nutrient cycling as an ecosystem service and thus engineer Arctic ecosystems on local scales. The enhanced productivity in patches on the landscape could subsequently affect plant diversity and the dispersion of herbivores on the tundra.

Franz Xaver Eder (1914 - 2009) Wanderer zwischen den Welten

NASA Astrophysics Data System (ADS)

Lindner, Sigrid; Hoffmann, Dieter

In seinem Essay "Die Struktur des historischen Universums" vergleicht Siegfried Kracauer die Mikrogeschichte mit den Großaufnahmen etwa von der Hand einer Figur, wie sie in Spielfilmen zwischengeschnitten werden.

Genetics Home Reference: Leber congenital amaurosis

MedlinePlus

... FP, van den Hurk JA, den Hollander AI. Molecular genetics of Leber congenital amaurosis. Hum Mol Genet. 2002 ... J. Leber congenital amaurosis: comprehensive survey of the genetic ... as a strategy for molecular diagnosis. Hum Mutat. 2004 Apr;23(4):306- ...

HyDEn: A Hybrid Steganocryptographic Approach for Data Encryption Using Randomized Error-Correcting DNA Codes

PubMed Central

Regoui, Chaouki; Durand, Guillaume; Belliveau, Luc; Léger, Serge

2013-01-01

This paper presents a novel hybrid DNA encryption (HyDEn) approach that uses randomized assignments of unique error-correcting DNA Hamming code words for single characters in the extended ASCII set. HyDEn relies on custom-built quaternary codes and a private key used in the randomized assignment of code words and the cyclic permutations applied on the encoded message. Along with its ability to detect and correct errors, HyDEn equals or outperforms existing cryptographic methods and represents a promising in silico DNA steganographic approach. PMID:23984392

Crowned dens syndrome diagnosed on ¹⁸F-FDG PET/CT.

PubMed

Monet, Antoine; Massonnat, Richard; Merino, Bertrand; Riviere, Annalisa; Richez, Christophe

2014-12-01

An 87-year-old woman with corticosteroid-resistant polymyalgia rheumatica underwent ¹⁸F-FDG PET/CT for suspected giant cell arteritis or neoplastic disease. FDG uptake in the immediate vicinity of the odontoid process, with a crownlike calcification, was identified on the CT scan on the posterior side of the dens, thus confirming the diagnosis of crowned dens syndrome. Because this rare syndrome is frequently misdiagnosed, nuclear physicians should be aware of the signs and symptoms of this condition, which may call for the use of PET/CT imagery.

A unique Austin Chalk reservoir, Van field, Van Zandt County, Texas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowe, J.T.

1990-09-01

Significant shallow oil production from the Austin Chalk was established in the Van field, Van Zandt County, in East Texas in the late 1980s. The Van field structure is a complexly faulted domal anticline created by salt intrusion. The Woodbine sands, which underlie the Austin Chalk, have been and continue to be the predominant reservoir rocks in the field. Evidence indicates that faults provided vertical conduits for migration of Woodbine oil into the Austin Chalk where it was trapped along the structural crest. The most prolific Austin Chalk production is on the upthrown side of the main field fault, asmore » is the Woodbine. The Austin Chalk is a soft, white to light gray limestone composed mostly of coccoliths with some pelecypods. Unlike the Austin Chalk in the Giddings and Pearsall fields, the chalk at Van was not as deeply buried and therefore did not become brittle and susceptible to tensional or cryptic fracturing. The shallow burial in the Van field was also important in that it allowed the chalk to retain primary microporosity. The production comes entirely from this primary porosity. In addition to the structural position and underlying oil source from the Woodbine, the depositional environment and associated lithofacies are also keys to the reservoir quality in the Van field as demonstrated by cores from the upthrown and downthrown (less productive) sides of the main field fault. It appears that at the time of Austin Chalk deposition, the main field fault was active and caused the upthrown side to be a structural high and a more agreeable environment for benthonic organisms such as pelecypods and worms. The resulting bioturbation enhanced the reservoir's permeability enough to allow migration and entrapment of the oil. Future success in exploration for analogous Austin Chalk reservoirs will require the combination of a favorable environment of deposition, a nearby Woodbine oil source, and a faulted trap that will provide the conduit for migration.« less

Habitat characteristics at den sites of the Point Arena mountain beaver (Aplodontia rufa nigra)

Treesearch

William J. Zielinski; John E. Hunter; Robin Hamlin; Keith M. Slauson; M. J. Mazurek

2010-01-01

The Point Arena mountain beaver (Aplodontia rufa nigra) is a federally listed endangered species, but has been the subject of few studies. Mountain beavers use burrows that include a single subterranean den. Foremost among the information needs for this subspecies is a description of the above-ground habitat features associated with dens. Using...

Motion Sickness When Driving With a Head-Slaved Camera System

DTIC Science & Technology

2003-02-01

YPR-765 under armour (Report TM-97-A026). Soesterberg, The Netherlands: TNO Human Factors Research Institute. Van Erp, J.B.F., Padmos, P. & Tenkink, E...Institute. Van Erp, J.B.F., Van den Dobbelsteen, J.J. & Padmos, P. (1998). Improved camera-monitor system for driving YPR-765 under armour (Report TM-98

Successful Ultra-Conservative Management of a Mandibular Premolar with Dens Invaginatus.

PubMed

Abazarpour, Ramin; Parirokh, Masoud; Farhadi, Aida; Jalali, Zahra; Kheirabadi, Nasir

2017-01-01

Dens invaginatus is one of the most common anomalies of tooth structure. It is caused by the invagination of the crown surface during odontogenesis that enters the pulp chamber of the affected tooth. Depending on the complexity of invagination, the tooth might present with pulp necrosis, open apex and a complicated root canal system. This case report presents an Oehlers' type 2 dens-invaginatus in a mandibular premolar with chronic apical abscess. In most cases, dens invaginatus is removed during treatment. However, in this case report, based on cone-beam computed tomography (CBCT) evaluation, non-surgical treatment and maintenance of the invaginated segment was chosen in order to prevent compromising the tooth structure and its susceptibility to future root fracture. This is a new treatment approach and has not been performed in previous reports. Calcium-enriched mixture (CEM) cement was used as an apical plug followed by gutta-percha in warm vertical compaction for root canal obturation. The case was followed up for 36 months after treatment. This report highlights the importance of selecting the appropriate treatment approach based on CBCT evaluation.

Stirling Powered Van Progam overview

NASA Technical Reports Server (NTRS)

Shaltens, R. K.

1986-01-01

The Stirling Powered Van Program (SPVP) is a multiyear, multiphase program to evaluate the automotive Stirling engine (ASE) in Air Force vans under realistic conditions. The objective of the SPVP is to transfer to manufacturer and end user(s) (i.e., on the path to commercialization) the second-generation Mod 2 ASE upon completion of the Automotive Stirling Engine Program in 1987. In order to meet this objective, the SPVP must establish Stirling performance, integrity, reliability, durability and maintainability. The ASE program background leading to the van program is reviewed and plans for evaluating the kinematic Stirling engine in Air Force vans examined. Also discussed are the NASA technology transfers to industry that have been accomplished and those which are currently being developed.

Lack of gp130 expression in hepatocytes attenuates tumor progression in the DEN model.

PubMed

Hatting, M; Spannbauer, M; Peng, J; Al Masaoudi, M; Sellge, G; Nevzorova, Y A; Gassler, N; Liedtke, C; Cubero, F J; Trautwein, C

2015-03-05

Chronic liver inflammation is a crucial event in the development and growth of hepatocellular carcinoma (HCC). Compelling evidence has shown that interleukin-6 (IL-6)/gp130-dependent signaling has a fundamental role in liver carcinogenesis. Thus, in the present study we aimed to investigate the role of gp130 in hepatocytes for the initiation and progression of HCC. Hepatocyte-specific gp130 knockout mice (gp130(Δhepa)) and control animals (gp130(f/f)) were treated with diethylnitrosamine (DEN). The role of gp130 for acute injury (0-144 h post treatment), tumor initiation (24 weeks) and progression (40 weeks) was analyzed. After acute DEN-induced liver injury we observed a reduction in the inflammatory response in gp130(Δhepa) animals as reflected by decreased levels of IL-6 and oncostatin M. The loss of gp130 slightly attenuated the initiation of HCC 24 weeks after DEN treatment. In contrast, 40 weeks after DEN treatment, male and female gp130(Δhepa) mice showed smaller tumors and reduced tumor burden, indicating a role for hepatocyte-specific gp130 expression during HCC progression. Oxidative stress and DNA damage were substantially and similarly increased by DEN in both gp130(f/f) and gp130(Δhepa) animals. However, gp130(Δhepa) livers revealed aberrant STAT5 activation and decreased levels of transforming growth factor-β (TGFβ), pSMAD2/3 and SMAD2, whereas phosphorylation of STAT3 at Tyr705 and Ser727 was absent. Our results indicate that gp130 deletion in hepatocytes reduces progression, but not HCC initiation in the DEN model. Gp130 deletion resulted in STAT3 inhibition but increased STAT5 activation and diminished TGF-dependent signaling. Hence, blocking gp130 in hepatocytes might be an interesting therapeutic target to inhibit the growth of HCC.

DenTimol as A Dendrimeric Timolol Analogue for Glaucoma Therapy: Synthesis and Preliminary Efficacy and Safety Assessment.

PubMed

Lancina, Michael G; Wang, Juan; Williamson, Geoffrey S; Yang, Hu

2018-05-30

In this work, we report the synthesis and characterization of DenTimol, a dendrimer-based polymeric timolol analog, as a glaucoma medication. A timolol precursor ( S)-4-[4-(oxiranylmethoxy)-1,2,5-thiadiazol-3-yl]morpholine (OTM) was reacted with the heterobifunctional amine polyethylene glycol acetic acid (amine-PEG-acetic acid, M n = 2000 g/mol) via a ring opening reaction of an epoxide by an amine to form the OTM-PEG conjugate. OTM-PEG was then coupled to an ethylenediamine (EDA) core polyamidoamine (PAMAM) dendrimer G3 to generate DenTimol using the N-(3-(dimethylamino)propyl)- N'-ethylcarbodiimide hydrochloride (EDC)/ N-hydroxysuccinimide (NHS) coupling reaction. MALDI mass spectrometry, 1 H NMR spectroscopy, and HPLC were applied to characterize the intermediate and final products. Ex vivo corneal permeation of DenTimol was assessed using the Franz diffusion cell system mounted with freshly extracted rabbit cornea. The cytotoxicity of DenTimol was assessed using the WST-1 assay. Our results show that DenTimol is nontoxic up to an OTM equivalent concentration of 100 μM. DenTimol is efficient at crossing the cornea. About 8% of the dendrimeric drug permeated through the cornea in 4 h. Its IOP-lowering effect was observed in normotensive adult Brown Norway male rats. Compared to the undosed eye, an IOP reduction by an average of 7.3 mmHg (∼30% reduction from baseline) was observed in the eye topically treated with DenTimol (2 × 5 μL, 0.5% w/v timolol equivalent) in less than 30 min. Daily dosing of DenTimol for a week did not cause any irritation or toxicity as confirmed by the histological examination of ocular tissues, including the cornea, ciliary body, and retina.

Catalogue of polar bear (Ursus maritimus) maternal den locations in the Beaufort Sea and neighboring regions, Alaska, 1910-2010

USGS Publications Warehouse

Durner, George M.; Fischbach, Anthony S.; Amstrup, Steven C.; Douglas, David C.

2010-01-01

This report presents data on the approximate locations and methods of discovery of 392 polar bear (Ursus maritimus) maternal dens found in the Beaufort Sea and neighboring regions between 1910 and 2010 that are archived by the U.S. Geological Survey, Alaska Science Center, Anchorage, Alaska. A description of data collection methods, biases associated with collection method, primary time periods, and spatial resolution are provided. Polar bears in the Beaufort Sea and nearby regions den on both the sea ice and on land. Standardized VHF surveys and satellite radio telemetry data provide a general understanding of where polar bears have denned in this region over the past 3 decades. Den observations made during other research activities and anecdotal reports from other government agencies, coastal residents, and industry personnel also are reported. Data on past polar bear maternal den locations are provided to inform the public and to provide information for natural resource agencies in planning activities to avoid or minimize interference with polar bear maternity dens.

Genetics Home Reference: Langerhans cell histiocytosis

MedlinePlus

... Oct;29(5):853-73. doi: 10.1016/j.hoc.2015.06.005. Epub 2015 Aug 18. Review. Citation on PubMed Nelson DS, van Halteren A, Quispel WT, van den Bos C, Bovée JV, Patel B, Badalian-Very G, van Hummelen P, Ducar M, Lin L, MacConaill LE, Egeler RM, ...

vanC Cluster of Vancomycin-Resistant Enterococcus gallinarum BM4174

PubMed Central

Arias, Cesar A.; Courvalin, Patrice; Reynolds, Peter E.

2000-01-01

Glycopeptide-resistant enterococci of the VanC type synthesize UDP-muramyl-pentapeptide[d-Ser] for cell wall assembly and prevent synthesis of peptidoglycan precursors ending in d-Ala. The vanC cluster of Enterococcus gallinarum BM4174 consists of five genes: vanC-1, vanXYC, vanT, vanRC, and vanSC. Three genes are sufficient for resistance: vanC-1 encodes a ligase that synthesizes the dipeptide d-Ala-d-Ser for addition to UDP-MurNAc-tripeptide, vanXYC encodes a d,d-dipeptidase–carboxypeptidase that hydrolyzes d-Ala-d-Ala and removes d-Ala from UDP-MurNAc-pentapeptide[d-Ala], and vanT encodes a membrane-bound serine racemase that provides d-Ser for the synthetic pathway. The three genes are clustered: the start codons of vanXYC and vanT overlap the termination codons of vanC-1 and vanXYC, respectively. Two genes which encode proteins with homology to the VanS-VanR two-component regulatory system were present downstream from the resistance genes. The predicted amino acid sequence of VanRC exhibited 50% identity to VanR and 33% identity to VanRB. VanSC had 40% identity to VanS over a region of 308 amino acids and 24% identity to VanSB over a region of 285 amino acids. All residues with important functions in response regulators and histidine kinases were conserved in VanRC and VanSC, respectively. Induction experiments based on the determination of d,d-carboxypeptidase activity in cytoplasmic extracts confirmed that the genes were expressed constitutively. Using a promoter-probing vector, regions upstream from the resistance and regulatory genes were identified that have promoter activity. PMID:10817725

Remote identification of potential polar bear maternal denning habitat in northern Alaska using airborne LiDAR

NASA Astrophysics Data System (ADS)

Jones, B. M.; Durner, G. M.; Stoker, J.; Shideler, R.; Perham, C.; Liston, G. E.

2013-12-01

Polar bear (Ursus maritimus) populations throughout the Arctic are being threatened by reductions in critical sea ice habitat. Throughout much of their range, polar bears give birth to their young in winter dens that are excavated in snowdrifts. New-born cubs, which are unable to survive exposure to Arctic winter weather, require 2-3 months of the relatively warm, stable, and undisturbed environment of the den for their growth. In the southern Beaufort Sea (BS), polar bears may den on the Alaskan Arctic Coastal Plain (ACP).The proportion of dens occurring on land has increased because of reductions in stable multi-year ice, increases in unconsolidated ice, and lengthening of the fall open-water period. Large portions of the ACP are currently being used for oil and gas activities and proposed projects will likely expand this footprint in the near future. Since petroleum exploration and development activities increase during winter there is the potential for human activities to disturb polar bears in maternal dens. Thus, maps showing the potential distribution of terrestrial denning habitat can help to mitigate negative interactions. Prior remote sensing efforts have consisted of manual interpretation of vertical aerial photography and automated classification of Interferometric Synthetic Aperture (IfSAR) derived digital terrain models (DTM) (5-m spatial resolution) focused on the identification of snowdrift forming landscape features. In this study, we assess the feasibility of airborne Light Detection and Ranging (LiDAR) data (2-m spatial resolution) for the automated classification of potential polar bear maternal denning habitat in a 1,400 km2 area on the central portion of the ACP. The study region spans the BS coast from the Prudhoe Bay oilfield in the west to near Point Thompson in the east and extends inland from 10 to 30 km. Approximately 800 km2 of the study area contains 19 known den locations, 51 field survey sites with information on bank height and

Characterisation of the selective binding of antibiotics vancomycin and teicoplanin by the VanS receptor regulating type A vancomycin resistance in the enterococci.

PubMed

Hughes, C S; Longo, E; Phillips-Jones, M K; Hussain, R

2017-08-01

A-type resistance towards "last-line" glycopeptide antibiotic vancomycin in the leading hospital acquired infectious agent, the enterococci, is the most common in the UK. Resistance is regulated by the VanR A S A two-component system, comprising the histidine sensor kinase VanS A and the partner response regulator VanR A . The nature of the activating ligand for VanS A has not been identified, therefore this work sought to identify and characterise ligand(s) for VanS A . In vitro approaches were used to screen the structural and activity effects of a range of potential ligands with purified VanS A protein. Of the screened ligands (glycopeptide antibiotics vancomycin and teicoplanin, and peptidoglycan components N-acetylmuramic acid, D-Ala-D-Ala and Ala-D-y-Glu-Lys-D-Ala-D-Ala) only glycopeptide antibiotics vancomycin and teicoplanin were found to bind VanS A with different affinities (vancomycin 70μM; teicoplanin 30 and 170μM), and were proposed to bind via exposed aromatic residues tryptophan and tyrosine. Furthermore, binding of the antibiotics induced quicker, longer-lived phosphorylation states for VanS A , proposing them as activators of type A vancomycin resistance in the enterococci. Copyright © 2017 Diamond Light Source Ltd. Published by Elsevier B.V. All rights reserved.

DenHunt - A Comprehensive Database of the Intricate Network of Dengue-Human Interactions

PubMed Central

Arjunan, Selvam; Sastri, Narayan P.; Chandra, Nagasuma

2016-01-01

Dengue virus (DENV) is a human pathogen and its etiology has been widely established. There are many interactions between DENV and human proteins that have been reported in literature. However, no publicly accessible resource for efficiently retrieving the information is yet available. In this study, we mined all publicly available dengue–human interactions that have been reported in the literature into a database called DenHunt. We retrieved 682 direct interactions of human proteins with dengue viral components, 382 indirect interactions and 4120 differentially expressed human genes in dengue infected cell lines and patients. We have illustrated the importance of DenHunt by mapping the dengue–human interactions on to the host interactome and observed that the virus targets multiple host functional complexes of important cellular processes such as metabolism, immune system and signaling pathways suggesting a potential role of these interactions in viral pathogenesis. We also observed that 7 percent of the dengue virus interacting human proteins are also associated with other infectious and non-infectious diseases. Finally, the understanding that comes from such analyses could be used to design better strategies to counteract the diseases caused by dengue virus. The whole dataset has been catalogued in a searchable database, called DenHunt (http://proline.biochem.iisc.ernet.in/DenHunt/). PMID:27618709

DenHunt - A Comprehensive Database of the Intricate Network of Dengue-Human Interactions.

PubMed

Karyala, Prashanthi; Metri, Rahul; Bathula, Christopher; Yelamanchi, Syam K; Sahoo, Lipika; Arjunan, Selvam; Sastri, Narayan P; Chandra, Nagasuma

2016-09-01

Dengue virus (DENV) is a human pathogen and its etiology has been widely established. There are many interactions between DENV and human proteins that have been reported in literature. However, no publicly accessible resource for efficiently retrieving the information is yet available. In this study, we mined all publicly available dengue-human interactions that have been reported in the literature into a database called DenHunt. We retrieved 682 direct interactions of human proteins with dengue viral components, 382 indirect interactions and 4120 differentially expressed human genes in dengue infected cell lines and patients. We have illustrated the importance of DenHunt by mapping the dengue-human interactions on to the host interactome and observed that the virus targets multiple host functional complexes of important cellular processes such as metabolism, immune system and signaling pathways suggesting a potential role of these interactions in viral pathogenesis. We also observed that 7 percent of the dengue virus interacting human proteins are also associated with other infectious and non-infectious diseases. Finally, the understanding that comes from such analyses could be used to design better strategies to counteract the diseases caused by dengue virus. The whole dataset has been catalogued in a searchable database, called DenHunt (http://proline.biochem.iisc.ernet.in/DenHunt/).

Genetics Home Reference: Silver syndrome

MedlinePlus

... PubMed Central Windpassinger C, Auer-Grumbach M, Irobi J, Patel H, Petek E, Hörl G, Malli R, Reed JA, Dierick I, Verpoorten N, Warner TT, Proukakis C, Van den Bergh P, Verellen C, Van Maldergem L, Merlini L, De ...

Technische Systeme für den Herzersatz und die Herzunterstützung

NASA Astrophysics Data System (ADS)

Schöb, Reto; Loree, Howard M.

Herzkrankheiten verursachen allein in den Vereinigten Staaten jährlich mehr als 700’000 Todesfälle. Ungefähr 3 Millionen Patienten in den U.S.A. leiden gemäss der American Heart Association (AHA) und dem National Heart, Lung and Blood Institute (NHLBI) an kongestivem Herzversagen (Congestive Heart Failure, CHF), welches eine chronische, sehr entkräftende und degenerative Krankheit ist: Das Herz ist dabei unfähig, hinreichend Blut zu den Organen des Körpers zu pumpen. Über 400’000 Fälle von CHF werden jedes Jahr diagnostiziert. Ähnliche Zahlen werden für Europa und Japan zusammen geschätzt. Basierend auf Daten vom AHA und NHLBI beträgt die fünfjährige Überlebensrate für CHF-Patienten lediglich etwa 50% [1]. 70’000-120’000 dieser Patienten könnten von einer Herzverpflanzung profitieren. 1999 wurden in den USA aber nur 2185 Herztransplantationen durchgeführt während die Warteliste über 4000 Patienten beträgt [2]. Ein akuter Mangel an Spenderherzen und die enormen Kosten (250’000-400’000 USD pro Patient) sind die begrenzenden Faktoren für Herztransplantationen [3]. Dies bedeutet, dass eine riesige Anzahl von Patienten durch ein zuverlässiges und verschleissfreies, nichtthrombotisches, total implantierbares, künstliches Herz gerettet werden könnten. Bis heute jedoch kein derartiges Implantat kommerziell verfügbar.

Successful Ultra-Conservative Management of a Mandibular Premolar with Dens Invaginatus

PubMed Central

Abazarpour, Ramin; Parirokh, Masoud; Farhadi, Aida; Jalali, Zahra; Kheirabadi, Nasir

2017-01-01

Dens invaginatus is one of the most common anomalies of tooth structure. It is caused by the invagination of the crown surface during odontogenesis that enters the pulp chamber of the affected tooth. Depending on the complexity of invagination, the tooth might present with pulp necrosis, open apex and a complicated root canal system. This case report presents an Oehlers’ type 2 dens-invaginatus in a mandibular premolar with chronic apical abscess. In most cases, dens invaginatus is removed during treatment. However, in this case report, based on cone-beam computed tomography (CBCT) evaluation, non-surgical treatment and maintenance of the invaginated segment was chosen in order to prevent compromising the tooth structure and its susceptibility to future root fracture. This is a new treatment approach and has not been performed in previous reports. Calcium-enriched mixture (CEM) cement was used as an apical plug followed by gutta-percha in warm vertical compaction for root canal obturation. The case was followed up for 36 months after treatment. This report highlights the importance of selecting the appropriate treatment approach based on CBCT evaluation. PMID:28808472

Softwaremodule voor het Simuleren van de Gevolgen van Raketonderschepping (The Dutch Program for the Simulation of Missile Intercept Effects)

DTIC Science & Technology

2007-07-01

effects (Softwaremodule voor het simuleren van de gevolgen van raketonderschepping) 11 . AUTHOR(S) Dr E. Abadjieva, MSc R.P. Sterkenburg, MSc F. Bouquet...Softwaremnodule voor het simuleren van de gevolgen van raketonderschepping D)attini Juli 2007 Auteur(s) dr. F. Abadjicva ir. R.P Sterkenburg ir. F. Bouquet ir...P.W. D)ouip Rubricering rapport O)ngerubri ceerd Vastgesteld door Maj R. 11 . Jongkinid Vastgesteld d.d. 12 juni 2007 (Deze nitining mizil-4 sict

Beslisbevoegdheden en Verantwoordelijkheden van de Uitgestegen Soldaat. Deel A: Verplaatsen van Beslisbevoegdheden (Authority and Responsibility of the Dismounted Soldier. Part A. Empowering the Dismounted Soldier)

DTIC Science & Technology

2007-04-01

en verantwoordelijkheden van de uitgestegen soldaat Deel A: verplaatsen van beslisbevoegdheden Datumn april 2007 Auteur (s) R. de Bruin ITE. van Bernmel...Admiraal, Bureau SMP Auteur (s) R. de Bruin Program maleider Projectleider I.E. van Bemnmel dr. W.A. Lotens, A.J. van Vliet, A.J. van Vijet TNO Defensie en...Leadership Theory en wordt relevant geacht voor de ontvangers van aanvullende beslisbevoegdheden. 2.1.3 Het oogmerk van de hogere commandant Een ander

The phosphotransferase VanU represses expression of four qrr genes antagonizing VanO-mediated quorum-sensing regulation in Vibrio anguillarum

PubMed Central

Weber, Barbara; Lindell, Kristoffer; El Qaidi, Samir; Hjerde, Erik; Willassen, Nils-Peder

2011-01-01

Vibrio anguillarum utilizes quorum sensing to regulate stress responses required for survival in the aquatic environment. Like other Vibrio species, V. anguillarum contains the gene qrr1, which encodes the ancestral quorum regulatory RNA Qrr1, and phosphorelay quorum-sensing systems that modulate the expression of small regulatory RNAs (sRNAs) that destabilize mRNA encoding the transcriptional regulator VanT. In this study, three additional Qrr sRNAs were identified. All four sRNAs were positively regulated by σ54 and the σ54-dependent response regulator VanO, and showed a redundant activity. The Qrr sRNAs, together with the RNA chaperone Hfq, destabilized vanT mRNA and modulated expression of VanT-regulated genes. Unexpectedly, expression of all four qrr genes peaked at high cell density, and exogenously added N-acylhomoserine lactone molecules induced expression of the qrr genes at low cell density. The phosphotransferase VanU, which phosphorylates and activates VanO, repressed expression of the Qrr sRNAs and stabilized vanT mRNA. A model is presented proposing that VanU acts as a branch point, aiding cross-regulation between two independent phosphorelay systems that activate or repress expression of the Qrr sRNAs, giving flexibility and precision in modulating VanT expression and inducing a quorum-sensing response to stresses found in a constantly changing aquatic environment. PMID:21948044

The phosphotransferase VanU represses expression of four qrr genes antagonizing VanO-mediated quorum-sensing regulation in Vibrio anguillarum.

PubMed

Weber, Barbara; Lindell, Kristoffer; El Qaidi, Samir; Hjerde, Erik; Willassen, Nils-Peder; Milton, Debra L

2011-12-01

Vibrio anguillarum utilizes quorum sensing to regulate stress responses required for survival in the aquatic environment. Like other Vibrio species, V. anguillarum contains the gene qrr1, which encodes the ancestral quorum regulatory RNA Qrr1, and phosphorelay quorum-sensing systems that modulate the expression of small regulatory RNAs (sRNAs) that destabilize mRNA encoding the transcriptional regulator VanT. In this study, three additional Qrr sRNAs were identified. All four sRNAs were positively regulated by σ(54) and the σ(54)-dependent response regulator VanO, and showed a redundant activity. The Qrr sRNAs, together with the RNA chaperone Hfq, destabilized vanT mRNA and modulated expression of VanT-regulated genes. Unexpectedly, expression of all four qrr genes peaked at high cell density, and exogenously added N-acylhomoserine lactone molecules induced expression of the qrr genes at low cell density. The phosphotransferase VanU, which phosphorylates and activates VanO, repressed expression of the Qrr sRNAs and stabilized vanT mRNA. A model is presented proposing that VanU acts as a branch point, aiding cross-regulation between two independent phosphorelay systems that activate or repress expression of the Qrr sRNAs, giving flexibility and precision in modulating VanT expression and inducing a quorum-sensing response to stresses found in a constantly changing aquatic environment.

Synthetic Minor NSR Permit: Van Hook Crude Terminal, LLC - Van Hook Crude Terminal/Rail Loading Facility

EPA Pesticide Factsheets

This page contains the current effective synthetic minor NSR permit for the Van Hook Crude Terminal, LLC, Van Hook Crude Terminal/Rail Loading Facility, located on the Fort Berthold Indian Reservation in Mountrail County, ND.

Glycopeptide Resistance vanA Operons in Paenibacillus Strains Isolated from Soil

PubMed Central

Guardabassi, Luca; Perichon, Bruno; van Heijenoort, Jean; Blanot, Didier; Courvalin, Patrice

2005-01-01

The sequence and gene organization of the van operons in vancomycin (MIC of >256 μg/ml)- and teicoplanin (MIC of ≥32 μg/ml)-resistant Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B isolated from soil were determined. Both operons had regulatory (vanR and vanS), resistance (vanH, vanA, and vanX), and accessory (vanY, vanZ, and vanW) genes homologous to the corresponding genes in enterococcal vanA and vanB operons. The vanAPT operon in P. thiaminolyticus PT-2B1 had the same gene organization as that of vanA operons whereas vanAPA in P. apiarius PA-B2B resembled vanB operons due to the presence of vanW upstream from the vanHAX cluster but was closer to vanA operons in sequence. Reference P. apiarius strains NRRL B-4299 and NRRL B-4188 were found to harbor operons indistinguishable from vanAPA by PCR mapping, restriction fragment length polymorphism, and partial sequencing, suggesting that this operon was species specific. As in enterococci, resistance was inducible by glycopeptides and associated with the synthesis of pentadepsipeptide peptidoglycan precursors ending in d-Ala-d-Lac, as demonstrated by d,d-dipeptidase activities, high-pressure liquid chromatography, and mass spectrometry. The precursors differed from those in enterococci by the presence of diaminopimelic acid instead of lysine in the peptide chain. Altogether, the results are compatible with the notion that van operons in soil Paenibacillus strains and in enterococci have evolved from a common ancestor. PMID:16189102

Glycopeptide resistance vanA operons in Paenibacillus strains isolated from soil.

PubMed

Guardabassi, Luca; Perichon, Bruno; van Heijenoort, Jean; Blanot, Didier; Courvalin, Patrice

2005-10-01

The sequence and gene organization of the van operons in vancomycin (MIC of >256 microg/ml)- and teicoplanin (MIC of > or =32 microg/ml)-resistant Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B isolated from soil were determined. Both operons had regulatory (vanR and vanS), resistance (vanH, vanA, and vanX), and accessory (vanY, vanZ, and vanW) genes homologous to the corresponding genes in enterococcal vanA and vanB operons. The vanA(PT) operon in P. thiaminolyticus PT-2B1 had the same gene organization as that of vanA operons whereas vanA(PA) in P. apiarius PA-B2B resembled vanB operons due to the presence of vanW upstream from the vanHAX cluster but was closer to vanA operons in sequence. Reference P. apiarius strains NRRL B-4299 and NRRL B-4188 were found to harbor operons indistinguishable from vanA(PA) by PCR mapping, restriction fragment length polymorphism, and partial sequencing, suggesting that this operon was species specific. As in enterococci, resistance was inducible by glycopeptides and associated with the synthesis of pentadepsipeptide peptidoglycan precursors ending in D-Ala-D-Lac, as demonstrated by D,D-dipeptidase activities, high-pressure liquid chromatography, and mass spectrometry. The precursors differed from those in enterococci by the presence of diaminopimelic acid instead of lysine in the peptide chain. Altogether, the results are compatible with the notion that van operons in soil Paenibacillus strains and in enterococci have evolved from a common ancestor.

Dens of northern flying squirrels in the Pacific Northwest.

Treesearch

A.B. Carey; T.M. Wilson; C.C. Maguire; B.L. Biswell

1997-01-01

Silvicultural prescriptions to enhance northern flying squirrel (Glaucoinys sabrinus) habitat have been suggested as an aid for recovery of the threatened northern spotted owl (Strix occidentalis caurina). Flying squirrels are hypothesized to be limited by den sites (cavities in trees) and by food (truffles). However, no...

Jao Van De Lagemaat | NREL

Science.gov Websites

Jao Van De Lagemaat Photo of Jao Vandelagemaat. Jao Van De Lagemaat Center Director: Chemistry and Lagemaat is currently the Center Director of the Chemistry and Nanoscience Center at NREL. He received his university. Education Ph.D. Physical Chemistry, University of Utrecht Featured Publications View all NREL

Proceedings of the Annual Conference of the International Group for the Psychology of Mathematics Education (9th, Noordwijkerhout, The Netherlands, July 22-29, 1985), Volume 1: Individual Contributions.

ERIC Educational Resources Information Center

Streefland, Leen, Ed.

This proceedings of the annual conference of the International Group for the Psychology of Mathematics Education (PME) includes the following research papers: "Calculators in Primary Education" (van den Brink); "Microworlds and Van Hiele Levels" (Dreyfus, Thompson); "Dynamical Mazes and the Ob-Serving Computer" (Harmegnies, Lowenthal); "Iterative…

Surgical orthodontic treatment of an impacted canine in the presence of dens invaginatus and follicular cyst.

PubMed

Spallarossa, Marialuce; Canevello, Carola; Silvestrini Biavati, Francesca; Laffi, Nicola

2014-01-01

Introduction. "Dens invaginatus" is a dental anomaly which originates from the invagination of the ameloblastic epithelium into the lingual surface of the dental crown during the odontogenesis. It can cause early pulpal necrosis, abscesses, retention or dislocation of contiguous elements, cysts, and internal resorptions. It normally affects the upper lateral incisors. In the following study the authors will discuss the etiology, the physiopathology, and the surgical-orthodontic management of a rare case of impacted canine associated with dens invaginatus and follicular cyst, with the aim of highlighting the importance of taking any therapeutic decision based on the data available in the literature. Case Report. The present study describes a combined surgical-orthodontic treatment of an impacted canine associated with a lateral incisor (2.2) suffering from type III dens invaginatus with radicular cyst, in a 15-year-old patient. Discussion. When treating a dens invaginatus there are different therapeutic solutions: they depend on the gravity of the anomaly and on the association with the retention of a permanent tooth. The aesthetic and functional restoration becomes extremely important when performing a surgical-orthodontic repositioning.

Beta-catenin: A Potential Survival Marker of Breast Cancer Stem Cells

DTIC Science & Technology

2006-09-01

T. C., Alexander, C. M., Georges-Labouesse, E., Van der Neut , R., Kreidberg, J. A., Jones, C. J., Sonnenberg, A. and Streuli, C. H. (2001...de Lau, W., Oving, I., Hurlstone, A., van der Horn, K., Batlle, E., Coudreuse, D., Haramis, A. P., Tjon-Pon-Fong, M., Moerer, P., van den Born, M...Scherer, D. C., Willert, K., Hintz, L., Nusse, R. & Weissman, I. L. (2003) Nature 423, 409-14. 36. van de Wetering, M., Sancho, E., Verweij, C

DEVILS DEN ROADLESS AREA, VERMONT.

USGS Publications Warehouse

Slack, John F.; Sabin, Andrew E.

1984-01-01

A mineral-resource survey was made of the Devils Den Roadless Area, Vermont, Geochemical sampling found traces of gold, copper, barium, lead, molybdenum, silver, tin, and thorium in rocks, stream sediments, and panned concentrates, but not in sufficient quantities to identify any resource potential. The only apparent resources are nonmetallic commodities including abundant rock suitable for crushihg, and very small deposits of sand and gravel and marble; these also occur outside the roadless area. The area was also evaluated for bedrock uranium and thorium deposits, but not anomalously high radioactive bedrock was found. A potential may exist for oil or natural gas at great depth, but this cannot be evaluated by the present study.

First evidence of gregarious denning in opossums (Didelphimorphia, Didelphidae), with notes on their social behaviour

PubMed Central

Astúa, Diego; Carvalho, Rafael A.; Maia, Paula F.; Magalhães, Arthur R.; Loretto, Diogo

2015-01-01

The Didelphidae are considered solitary opossums with few social interactions, usually limited to mating-related or mother–pouch young interactions. Anecdotal reports suggest that additional interactions occur, including den sharing by a few individuals, usually siblings. Here, we report novel observations that indicate opossums are more social than previously thought. These include nest sharing by males and females of Marmosa paraguayana, Gracilinanus microtarsus and Marmosops incanus prior to the onset of the breeding season and without signs of sexual activity; this is taken to indicate early pair-bonding matching and cooperative nest building. We also recorded den sharing among recently weaned siblings of Didelphis aurita and Caluromys philander. In addition, we observed 13 individuals of Didelphis albiventris representing three age classes resting without agonistic interactions in a communal den. These are the first reports of gregarious behaviour involving so many individuals, which are either unrelated or represent siblings from at least two litters, already weaned, sharing the same den with three adults. Sociality in opossums is probably more complex than previously established, and field experimental designs combining the use of artificial nests with camera traps or telemetry may help to gauge the frequency and extent of these phenomena. PMID:26085500

Obituary: James Alfred Van Allen, 1914-2006

NASA Astrophysics Data System (ADS)

Ludwig, George H.; McIlwain, Carl Edwin

2006-12-01

James Alfred Van Allen, world-renowned space scientist, died 9 August 2006 at the age of ninety-one. He succumbed to heart failure after a ten-week period of declining health. Van Allen served for his entire sixty-seven-year professional career as an amazingly productive researcher, space science spokesman, inspired teacher, and valued colleague. The realization by him and his associates that charged particles are trapped by the Earth's magnetic field began a whole new field of research, magnetospheric physics. Following that initial discovery, he and his associates quickly extended their observations, first to the inner planets, and then to the rest of the planets and beyond. During his tenure at Iowa, he and his group flew instruments on more than sixty successful Earth satellites and planetary spacecraft, including the first missions to the planets Venus, Mars, Jupiter, Saturn, Uranus, and Neptune. Van Allen's lifetime publication list numbers more than 275, of which many are widely-cited, seminal papers. He was the sole author of more than 125 of those papers. Beyond the research laboratory, Van Allen worked energetically throughout his career in establishing space research as a new branch of human inquiry. He was among the most sought-after as a committee member and adviser, working at the highest levels of government, including the White House and Congress, and at all levels of the national and international research establishments. Many presentations in the non-scientific arena helped to bring the exciting discoveries and challenges of space research to the attention of the general public. James Van Allen (Van to his many friends and colleagues) was born on 7 September 1914 on a small farm near Mount Pleasant, Iowa, the second of four sons of Alfred Morris Van Allen and Alma Olney Van Allen. After high school in Mount Pleasant, he entered Iowa Wesleyan College, majoring in physics and graduating summa cum laude. While there, he was introduced to geophysics

24. Typical 1bedroom apartment, from entry hall, den (right) bedroom ...

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

24. Typical 1-bedroom apartment, from entry hall, den (right) bedroom (left), and kitchen (not shown) on left. - Techwood Homes, Building No. 5, 467 Techwood Drive & 114-120 Pine Street, Atlanta, Fulton County, GA

A Look at Psychometrics in the Netherlands.

ERIC Educational Resources Information Center

Hambleton, Ronald K.; Swaminathan, H.

Comments are made on the review papers presented by six Dutch psychometricians: Ivo Molenaar, Wim van der Linden, Ed Roskam, Arnold Van den Wollenberg, Gideon Mellenbergh, and Dato de Gruijter. Molenaar has embraced a pragmatic viewpoint on Bayesian methods, using both empirical and pure approaches to solve educational research problems. Molenaar…

21. Typical 2bedroom apartment with entry into den, hallway with ...

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

21. Typical 2-bedroom apartment with entry into den, hallway with bathroom and bedrooms (right). Entry to kitchen (left). - Techwood Homes, Building No. 5, 467 Techwood Drive & 114-120 Pine Street, Atlanta, Fulton County, GA

27. Typical 2bedroom apartment with entry into den, hallway with ...

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

27. Typical 2-bedroom apartment with entry into den, hallway with bathroom and bedrooms (left), entry to kitchen (right) - Techwood Homes, Building No. 6, 465 Techwood Drive & 119-125 Hunnicutt Street, Atlanta, Fulton County, GA

Surgical Orthodontic Treatment of an Impacted Canine in the Presence of Dens Invaginatus and Follicular Cyst

PubMed Central

Canevello, Carola; Laffi, Nicola

2014-01-01

Introduction. “Dens invaginatus” is a dental anomaly which originates from the invagination of the ameloblastic epithelium into the lingual surface of the dental crown during the odontogenesis. It can cause early pulpal necrosis, abscesses, retention or dislocation of contiguous elements, cysts, and internal resorptions. It normally affects the upper lateral incisors. In the following study the authors will discuss the etiology, the physiopathology, and the surgical-orthodontic management of a rare case of impacted canine associated with dens invaginatus and follicular cyst, with the aim of highlighting the importance of taking any therapeutic decision based on the data available in the literature. Case Report. The present study describes a combined surgical-orthodontic treatment of an impacted canine associated with a lateral incisor (2.2) suffering from type III dens invaginatus with radicular cyst, in a 15-year-old patient. Discussion. When treating a dens invaginatus there are different therapeutic solutions: they depend on the gravity of the anomaly and on the association with the retention of a permanent tooth. The aesthetic and functional restoration becomes extremely important when performing a surgical-orthodontic repositioning. PMID:24963421

Consequences of the Introduction of Insensitive Munitions on Safety, Collateral Damage and Operations (consequenties van de invoering van mkm-munitie op veiligheid, gevolgschade en (internationaal) opereren

DTIC Science & Technology

2006-06-01

van de werkzaamheden In dit rapport worden de gevolgen van initiatie van munitie door een ongewilde externe stimulus beschouwd aan de hand van reele...operationele scenario’s. Dit wordt vergeleken met de gevolgen in dezelfde scenario’s, waarin gebruik is gemaakt van Minder Kwetsbare Munitie (MKM). Naast...de historie van MKM wordt uitgelegd wat Inleiding of terroristische activiteiten, maar ook door MKM is. Vervolgens worden de gevolgen Munitie en de

Chlorhexidine Induces VanA-Type Vancomycin Resistance Genes in Enterococci

PubMed Central

Bhardwaj, Pooja; Ziegler, Elizabeth

2016-01-01

Chlorhexidine is a bisbiguanide antiseptic used for infection control. Vancomycin-resistant E. faecium (VREfm) is among the leading causes of hospital-acquired infections. VREfm may be exposed to chlorhexidine at supra- and subinhibitory concentrations as a result of chlorhexidine bathing and chlorhexidine-impregnated central venous catheter use. We used RNA sequencing to investigate how VREfm responds to chlorhexidine gluconate exposure. Among the 35 genes upregulated ≥10-fold after 15 min of exposure to the MIC of chlorhexidine gluconate were those encoding VanA-type vancomycin resistance (vanHAX) and those associated with reduced daptomycin susceptibility (liaXYZ). We confirmed that vanA upregulation was not strain or species specific by querying other VanA-type VRE. VanB-type genes were not induced. The vanH promoter was found to be responsive to subinhibitory chlorhexidine gluconate in VREfm, as was production of the VanX protein. Using vanH reporter experiments with Bacillus subtilis and deletion analysis in VREfm, we found that this phenomenon is VanR dependent. Deletion of vanR did not result in increased chlorhexidine susceptibility, demonstrating that vanHAX induction is not protective against chlorhexidine. As expected, VanA-type VRE is more susceptible to ceftriaxone in the presence of sub-MIC chlorhexidine. Unexpectedly, VREfm is also more susceptible to vancomycin in the presence of subinhibitory chlorhexidine, suggesting that chlorhexidine-induced gene expression changes lead to additional alterations in cell wall synthesis. We conclude that chlorhexidine induces expression of VanA-type vancomycin resistance genes and genes associated with daptomycin nonsusceptibility. Overall, our results indicate that the impacts of subinhibitory chlorhexidine exposure on hospital-associated pathogens should be further investigated in laboratory studies. PMID:26810654

Emergence of vanA Enterococcus faecium in Denmark, 2005-15.

PubMed

Hammerum, Anette M; Baig, Sharmin; Kamel, Yasmin; Roer, Louise; Pinholt, Mette; Gumpert, Heidi; Holzknecht, Barbara; Røder, Bent; Justesen, Ulrik S; Samulioniené, Jurgita; Kjærsgaard, Mona; Østergaard, Claus; Holm, Anette; Dzajic, Esad; Søndergaard, Turid Snekloth; Gaini, Shahin; Edquist, Petra; Alm, Erik; Lilje, Berit; Westh, Henrik; Stegger, Marc; Hasman, Henrik

2017-08-01

To describe the changing epidemiology of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis in clinical samples in Denmark 2005-15 according to species and van type, and, furthermore, to investigate the genetic relatedness of the clinical E. faecium isolates from 2015. During 2005-14, all clinical VRE isolates were tested for the presence of vanA/B/C genes by PCR. In 2015, all clinical VRE isolates were whole-genome sequenced. From the WGS data, the presence of van genes and MLST STs were extracted in silico . Core-genome MLST (cgMLST) analysis was performed for the vancomycin-resistant E. faecium isolates. During 2005-15, 1043 vanA E. faecium , 25 vanB E. faecium , 4 vanA E. faecalis and 28 vanB E. faecalis were detected. The number of VRE was <50 isolates/year until 2012 to > 200 isolates/year in 2013-15. In 2015, 368 vanA E. faecium and 1 vanB E. faecium were detected along with 1 vanA E. faecalis and 1 vanB E. faecalis . cgMLST subdivided the 368 vanA E. faecium isolates into 33 cluster types (CTs), whereas the vanB E. faecium isolate belonged to a different CT. ST203-CT859 was most prevalent (51%), followed by ST80-CT14 (22%), ST117-CT24 (6%), ST80-CT866 (4%) and ST80-CT860 (2%). Comparison with the cgMLST.org database, previous studies and personal communications with neighbouring countries revealed that the novel cluster ST203-CT859 emerged in December 2014 and spread to the south of Sweden and the Faroe Islands during 2015. VRE increased in Denmark during 2005-15 due to the emergence of several vanA E. faecium clones. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A Conversation with William Van Til.

ERIC Educational Resources Information Center

Beineke, John A.

1989-01-01

Reports an interview with William Van Til, Coffman Distinguished Professor Emeritus of Education at Indiana State University (Terre Haute). Van Til reviews his career as a social studies teacher and his writings on curriculum and social foundations. Presents his opinions on progressive education, famous educators, educational history and reform,…

Additional Value from Road Mapping in Defense Policy Making (meerwaarde van roadmapping bij beleidsontwikkeling van de koninklijke landmacht)

DTIC Science & Technology

2006-05-01

van zogonaamde strategische reserves tot bijvaarbeeld lakaal boschikbare gevechtscapacitoit. 9 11 Joint. Do Nederlandse krijgsmacht ontwikkelt zich tot...8 2 W erkwijze van de KL tot nu toe ............................................................................... 9 2.1 O...ntwikkeling visiedocurnent ....................................................................................... 9 2.2 Opzet beleid- en deelstudies

Transient aerodynamic characteristics of vans during the accelerated overtaking process

NASA Astrophysics Data System (ADS)

Liu, Li-ning; Wang, Xing-shen; Du, Guang-sheng; Liu, Zheng-gang; Lei, Li

2018-04-01

This paper studies the influence of the accelerated overtaking process on the vehicles' transient aerodynamic characteristics, through 3-D numerical simulations with dynamic meshes and sliding interface technique. Numerical accuracy is verified by experimental results. The aerodynamic characteristics of vehicles in the uniform overtaking process and the accelerated overtaking process are compared. It is shown that the speed variation of the overtaking van would influence the aerodynamic characteristics of the two vans, with greater influence on the overtaken van than on the overtaking van. The simulations of three different accelerated overtaking processes show that the greater the acceleration of the overtaking van, the larger the aerodynamic coefficients of the overtaken van. When the acceleration of the overtaking van increases by 1 m/s2, the maximum drag force, side force and yawing moment coefficients of the overtaken van all increase by more than 6%, to seriously affect the power performance and the stability of the vehicles. The analysis of the pressure fields under different accelerated conditions reveals the cause of variations of the aerodynamic characteristics of vehicles.

The Dramatic Methods of Hans van Dam.

ERIC Educational Resources Information Center

van de Water, Manon

1994-01-01

Interprets for the American reader the untranslated dramatic methods of Hans van Dam, a leading drama theorist in the Netherlands. Discusses the functions of drama as a method, closed dramatic methods, open dramatic methods, and applying van Dam's methods. (SR)

The Advantages of Hybrid 4DEnVar in the Context of the Forecast Sensitivity to Initial Conditions

NASA Astrophysics Data System (ADS)

Song, Hyo-Jong; Shin, Seoleun; Ha, Ji-Hyun; Lim, Sujeong

2017-11-01

Hybrid four-dimensional ensemble variational data assimilation (hybrid 4DEnVar) is a prospective successor to three-dimensional variational data assimilation (3DVar) in operational weather prediction centers currently developing a new weather prediction model and those that do not operate adjoint models. In experiments using real observations, hybrid 4DEnVar improved Northern Hemisphere (NH; 20°N-90°N) 500 hPa geopotential height forecasts up to 5 days in a NH summer month compared to 3DVar, with statistical significance. This result is verified against ERA-Interim through a Monte Carlo test. By a regression analysis, the sensitivity of 5 day forecast is associated with the quality of the initial condition. The increased analysis skill for midtropospheric midlatitude temperature and subtropical moisture has the most apparent effect on forecast skill in the NH including a typhoon prediction case. Through attributing the analysis improvements by hybrid 4DEnVar separately to the ensemble background error covariance (BEC), its four-dimensional (4-D) extension, and climatological BEC, it is revealed that the ensemble BEC contributes to the subtropical moisture analysis, whereas the 4-D extension does to the midtropospheric midlatitude temperature. This result implies that hourly wind-mass correlation in 6 h analysis window is required to extract the potential of hybrid 4DEnVar for the midlatitude temperature analysis to the maximum. However, the temporal ensemble correlation, in hourly time scale, between moisture and another variable is invalid so that it could not work for improving the hybrid 4DEnVar analysis.

Van der Waals interaction in uniaxial anisotropic media.

PubMed

Kornilovitch, Pavel E

2013-01-23

Van der Waals interactions between flat surfaces in uniaxial anisotropic media are investigated in the nonretarded limit. The main focus is the effect of nonzero tilt between the optical axis and the surface normal on the strength of the van der Waals attraction. General expressions for the van der Waals free energy are derived using the surface mode method and the transfer-matrix formalism. To facilitate numerical calculations a temperature-dependent three-band parameterization of the dielectric tensor of the liquid crystal 5CB is developed. A solid slab immersed in a liquid crystal experiences a van der Waals torque that aligns the surface normal relative to the optical axis of the medium. The preferred orientation is different for different materials. Two solid slabs in close proximity experience a van der Waals attraction that is strongest for homeotropic alignment of the intervening liquid crystal for all the materials studied. The results have implications for the stability of plate-like colloids in liquid crystal hosts.

Margaret Cavendish's materialist critique of van Helmontian chymistry.

PubMed

Clucas, Stephen

2011-03-01

A striking omission in the scholarship on the reception of the chymical philosophy of Jan Baptista van Helmont in England in the seventeenth century is the work of the mid-seventeenth-century natural philosopher Margaret Cavendish, Duchess of Newcastle. In her Philosophical Letters (1664), Cavendish offers an extended critique of Van Helmont's work (whose Ortus Medicince had recently been translated into English by John Sadler). In this paper, I compare Cavendish's criticisms with those of Robert Boyle in his Sceptical Chymist (1661). Both Boyle and Cavendish attacked Van Helmont for the obscurity of his chymical vocabulary and concepts, and attacked his seminalism. Although their critiques had much in common, they diverged in their attitudes to Van Helmont's experiments. As an opponent of the experimental philosophy, Cavendish had little interest in the quality of Van Helmont's experimental claims, whereas Boyle was critical of their unreplicability. I also try to show that the two writers had very different polemical agendas, with Boyle defending his vision of chymistry based on a corpuscularian natural philosophy, and Cavendish being as much concerned with establishing her religious orthodoxy as with defending the truth claims of her own materialist vitalism. For Cavendish, Van Helmont was an example of the dangers of mingling theology and natural philosophy.

Activity rhythms and distribution of natal dens for red foxes

USGS Publications Warehouse

Wenyang, Zhou; Wanhong, Wei; Biggins, Dean E.

1995-01-01

The red fox, Vulpes vulpes, was investigated with snow tracking, radiotracking and directive observation at the Haibei Research Station of Alpine Meadow Ecosystem, Academia Sinica, from March to September 1994. The objectives of this study were to determine the distribution and use of natal dens, activity rhythms, and home range sizes for the foxes.

Van Go: A Labor of Love

ERIC Educational Resources Information Center

Williams, Jennifer

2012-01-01

Like a tapestry woven with one outstanding thread from beginning to end, the author's forty-year tenure as an art educator has its golden thread in her Van Go art outreach project. Quite literally, she takes students in a "van" and they "go," mostly on dirt roads, taking art to rural schools in Idaho, some of which have no more…

Genetics Home Reference: van der Woude syndrome

MedlinePlus

... What is the prognosis of a genetic condition? Genetic and Rare Diseases Information Center Frequency Van der Woude syndrome is believed to occur in 1 in 35,000 to 1 in 100,000 people, based on data from Europe and Asia. Van der Woude syndrome ...

CMMI Roadmaps

DTIC Science & Technology

2008-11-01

Attendees of the SPIder Workshop D. Bierhuizen—Medis Medical Imaging Systems L. Braafhart—LogicaCMG Nederland H.J.J. Cannegieter—SYSQA W. den...Dekker—LogicaCMG Nederland L. Delmelk—LogicaCMG België A.J. Donderman—Transfer Solutions G.H.M. Friedhoff—SYSQA L.L. van der Giessen—ABN AMRO M...Mechelen—Compuware Nederland M.P.H.M. Mermans—Philips Medical Systems C. Michielsen—ITIB N. van Mourik—SYSQA E.M. Oostveen—Advanced M.H.M. van

Enhancement of DEN-induced liver tumorigenesis in heme oxygenase-1 G143H mutant transgenic mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jin, Jianfeng; Wang, Dayong; Xiao, Haifeng

Heme oxygenase (HO) is the rate-limiting enzyme in heme metabolism. HO-1 exhibits anti-oxidative and anti-inflammatory function via the actions of its metabolite, respectively. A growing body of evidence demonstrates that HO-1 is implicated in the pathogenesis and progression of several types of cancer. However, whether HO-1 takes part in healthy-premalignant-malignant transformation is still undefined. In this study, we took advantage of transgenic mice which over-expressed HO-1 dominant negative mutant (HO-1 G143H) and observed its susceptibility to DEN-induced hepatocarcinogenesis. Our results indicate that HO-1 G143H mutant accelerates the progression of tumorigenesis and tumor growth. The mechanism is closely related to enhancementmore » of ROS production which induce more hepatocytes death and secretion of inflammatory cytokines, proliferation of surviving hepatocytes. Our result provides the direct evidence that HO-1 plays an important protective role in liver carcinogenesis. Alternatively, we suggest the possible explanation on effect of HO-1 promoter polymorphism which involved in tumorigenesis. - Highlights: • Enhancement of DEN-induced hepatocarcinogenesis in HO-1 G143H Tg mice. • HO-1G143H mutant enhanced DEN-induced ROS production and liver injury. • HO-1G143H mutant aggravated DEN-induced changes of inflammatory factors and cell proliferation.« less

UPS Hybrid Electric Delivery Van Testing | Transportation Research | NREL

Science.gov Websites

conventional diesel vans. Publications The following documents provide detailed information about the study the conventional vans during the on-road portion of the study. The two vehicle groups switched route assignments during the study period to provide a balanced review of the vans on the same routes. During

Genetics Home Reference: Ellis-van Creveld syndrome

MedlinePlus

... CREVELD SYNDROME Sources for This Page Baujat G, Le Merrer M. Ellis-van Creveld syndrome. Orphanet J Rare Dis. 2007 Jun ... CB, Kochilas L, Schimmenti LA, Moller JH. Ellis-van Creveld syndrome and congenital heart defects: presentation of an additional 32 cases. Pediatr Cardiol. 2011 Oct;32( ...

Psychometric properties of DAPonDEN: definitions, attitudes and practices in relation to diarrhea during enteral nutrition questionnaire.

PubMed

Majid, Hazreen A; Bin Sidek, Muhamad Adam; Chinna, Karuthan

2013-01-01

To investigate the psychometric properties of the developed 21 item questionnaire to measure definitions, attitudes and management practices in relation to diarrhea during enteral nutrition (DAPonDEN). Data were analyzed using exploratory factor analysis from a cross sectional study of 102 nurses aged 18 and over, conducted from December 2011 to February 2012 in Malaysia. Face and content validity of DAPonDEN were first evaluated by few expert panels and patients. For this study, adult nurses were recruited from the adult wards. In the final model, three items in DAPonDEN were dropped. In the exploratory factor analysis, five factors were extracted that explained a total of 55% of the variation in the remaining 18 items. The Kaiser-Meyer-Olkin (KMO) value was 0.723. For definition, there were two underlying factors: 'Key items in defining diarrhea' and 'non-key items in defining diarrhea'. For attitude there was a single factor. For practice, there were two underlying factors: 'enteral nutrition (EN) related' and 'awareness related'. The items in each of the underlying dimensions seem to measure the respective concepts for definition, attitude and practices adequately. The 18-items DAPonDEN instrument can be a suitable education tool to be used in relation to diarrhea during EN. Copyright © 2013 Elsevier Inc. All rights reserved.

Rückwärtsintegration - Zu den Verhältnissen Gymnasium, Hochschule und Arbeitswelt

NASA Astrophysics Data System (ADS)

Schmid, Gerhard; Heppner, Winfried; Focht, Eva

In seiner 2007 erschienen Sammlung von Vorträgen und Essays beschäftigt sich Wolfgang Frühwald, mit der Frage "Wieviel Wissen brauchen wir?“ [1] Die Kernproblematik moderner Wissenschaft und Forschung sieht der Autor, emeritierter Ordinarius für Neuere Deutsche Literaturwissenschaft und von 1992 bis 1997 Präsident der Deutschen Forschungsgemeinschaft, einerseits in der zunehmenden Spezialisierung der Wissenschaftsbereiche, andererseits in der Gefahr der Abkoppelung der Naturwissenschaften von den Geisteswissenschaften. Wiederholt plädiert er dafür, über der rasanten Entwicklung beispielsweise in der Biologie und Physik, die historische, gesellschaftliche und besonders die ethische Dimension der Forschung nicht zu übersehen und fordert eine übergeordnete Theorie der Wissenschaft, die nur im Dialog zwischen den einzelnen Fachgebieten zu entwickeln sei.

CheckDen, a program to compute quantum molecular properties on spatial grids.

PubMed

Pacios, Luis F; Fernandez, Alberto

2009-09-01

CheckDen, a program to compute quantum molecular properties on a variety of spatial grids is presented. The program reads as unique input wavefunction files written by standard quantum packages and calculates the electron density rho(r), promolecule and density difference function, gradient of rho(r), Laplacian of rho(r), information entropy, electrostatic potential, kinetic energy densities G(r) and K(r), electron localization function (ELF), and localized orbital locator (LOL) function. These properties can be calculated on a wide range of one-, two-, and three-dimensional grids that can be processed by widely used graphics programs to render high-resolution images. CheckDen offers also other options as extracting separate atom contributions to the property computed, converting grid output data into CUBE and OpenDX volumetric data formats, and perform arithmetic combinations with grid files in all the recognized formats.

Heath Van Essen

EPA Pesticide Factsheets

The EPA is providing notice of a proposed Administrative Penalty Assessment against Heath Van Essen, Respondent, an individual who owns or operates an animal feeding operation (“Facility”) that is located in Section 27 of Township 98 North, Range 47 West,

Endodontic retreatment of dens invaginatus presenting with gutta-percha overfilling at the attached gingiva and chronic apical periodontitis: unusual clinical report.

PubMed

Robazza, Carlos Roberto Colombo; Alves e Motta, Julio Cesar; de Carli, Marina Lara; de Oliveira Pedreira, Fernanda Rafaelly; Hanemann, Joao Adolfo Costa

2013-05-01

This work describes the retreatment of an unusual case of dens invaginatus with gutta-percha overfilling at the gingival mucosa and chronic apical periodontitis in a 34-year-old woman. Initial periapical radiograph showed the presence of type II dens invaginatus with poor quality obturation, root perforation and chronic apical periodontitis of tooth 22. Dens invaginatus is a tooth malformation caused by infolding of the dental papilla during tooth development. This anomaly has been associated with increased prevalence of pulpal and periapical diseases. Conventional endodontic retreatment was performed using rotary files and calcium hydroxide paste as intracanal dressing. After 7 days, root canal was filled with guttapercha points and Sealapex® sealer. Obturation was radiographically followed and, after 3 years, absence of fistula and periapical radiolucency was observed, thus conventional endodontic therapy proved to be successful. Conventional endodontic retreatment of type II dens invaginatus has been successful for a 3-year period, showing a better treatment alternative. Conservative endodontic retreatment of dens invaginatus should be considered to promote periapical healing with complete reconstitution of bone and periodontal ligament regeneration without signs of recurrence over a period of 3 years. Moreover, it preserves the entire tooth.

Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?

Treesearch

Winston P. Smith; Keith M. Endres

2012-01-01

We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the land-scape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover...

77 FR 14583 - Notice to Manufacturers of Alternative Fuel Vans

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-12

... Alternative Fuel Vans AGENCY: Federal Aviation Administration (FAA), U.S. DOT. ACTION: Notice to Manufacturers of Alternative Fuel Vans. SUMMARY: Projects funded under the Airport Improvement Program (AIP) must... (FAA) is considering issuing waivers to foreign manufacturers of alternative fuel vans. This notice...

Obituary: Thomas C. Van Flandern (1940-2009)

NASA Astrophysics Data System (ADS)

Dunham, David; Slabinski, Victor

2011-12-01

Dr. Thomas Charles Van Flandern, an expert in celestial mechanics and cosmology, died January 9, 2009 in Seattle, Washington, of colon cancer. He was 68. Van Flandern was an astronomer at the U.S. Naval Observatory from 1963 to 1983. He developed software to predict and analyze lunar occultations to improve lunar orbital and fundamental star catalog data. In later years he championed increasingly controversial theories. But his 1978 prediction that some asteroids have natural satellites, which was almost universally rejected, was verified when the Galileo spacecraft photographed Dactyl, a satellite of (243) Ida, during its flyby in 1993. Besides astronomy and computers, he had strong interests in biochemistry and nutrition, and he ran a business selling personal computers in the 1980s. Tom Van Flandern was born June 26, 1940 in Cleveland, Ohio, the first child of Robert F. Van Flandern and Anna Mary Haley. His father, a police officer, left the family when Tom Van Flandern was 5. His mother died when he was 16; he and his siblings then lived with their grandmother, Margery Jobe, until he went to college. Tom Van Flandern became interested in astronomy as a child. He used his first telescope, purchased with newspaper delivery earnings, to observe lunar occultations, and then learned how to predict them, sparking a life-long passion for dynamical astronomy. While attending St. Ignatius High School, Van Flandern and fellow student Thomas Petrie organized the Cleveland Moonwatch team to observe the first artificial satellites, the only team without an adult organizer. In 1958, Tom Van Flandern entered Xavier University where he led the Cincinnati Moonwatch team. He learned computer programming at a summer job with General Electric and wrote software to calculate "look angles" from orbital elements. The Cincinnati team became a top producer of observations using these predictions. Tom obtained a B.S. in mathematics from Xavier in 1962. He spent the next year at

‘Neanderthal bone flutes’: simply products of Ice Age spotted hyena scavenging activities on cave bear cubs in European cave bear dens

PubMed Central

Diedrich, Cajus G.

2015-01-01

Punctured extinct cave bear femora were misidentified in southeastern Europe (Hungary/Slovenia) as ‘Palaeolithic bone flutes’ and the ‘oldest Neanderthal instruments’. These are not instruments, nor human made, but products of the most important cave bear scavengers of Europe, hyenas. Late Middle to Late Pleistocene (Mousterian to Gravettian) Ice Age spotted hyenas of Europe occupied mainly cave entrances as dens (communal/cub raising den types), but went deeper for scavenging into cave bear dens, or used in a few cases branches/diagonal shafts (i.e. prey storage den type). In most of those dens, about 20% of adult to 80% of bear cub remains have large carnivore damage. Hyenas left bones in repeating similar tooth mark and crush damage stages, demonstrating a butchering/bone cracking strategy. The femora of subadult cave bears are intermediate in damage patterns, compared to the adult ones, which were fully crushed to pieces. Hyenas produced round–oval puncture marks in cub femora only by the bone-crushing premolar teeth of both upper and lower jaw. The punctures/tooth impact marks are often present on both sides of the shaft of cave bear cub femora and are simply a result of non-breakage of the slightly calcified shaft compacta. All stages of femur puncturing to crushing are demonstrated herein, especially on a large cave bear population from a German cave bear den. PMID:26064624

Microgravity

NASA Image and Video Library

1992-04-24

Overall view of the Vapor Crystal Growth System (VCGS) Furnace. Used on IML-1 International Microgravity Laboratory Spacelab 3. Principal Investigator and Payload Specialist was Lodewijk van den Berg.

Microgravity

NASA Image and Video Library

1992-04-24

Ampoule view of the Vapor Crystal Growth System (VCGS) Furnace. Used on IML-1 International Microgravity Laboratory Spacelab 3. Prinicipal Investigator and Payload Specialist was Lodewijk van den Berg.

Arnoldus Van Rhijn on aphasia: a forgotten thesis.

PubMed

Eling, Paul

2011-01-01

Aphasia formed a central topic in the discussion on localization of function in the nineteenth century, in particular in France, Germany and Great Brittain. Little is known on contributions from the Netherlands. This paper aims to discuss the contents of Arnoldus Van Rhijn's dissertation on aphasia, written in 1868 and one of the very few Dutch contributions to aphasiology in the nineteenth century. Added to this paper is a translation of the "Physiological Part" of Van Rhijn's dissertation. Van Rhijn discussed three cases with acquired aphasia. He rejected Broca's notion of a cortical center for the articulation of speech and instead regarded the cortex as the site where the will exerted its influence. He argued that there is a certain form of specialization: the will to say something is localized at a different place than the will to write. According to Van Rhijn, the highest motor centers are localized in the subcortical gray areas. Van Rhijn concluded that aphasia may result from lesions to the cortical centers involved in speaking, or from a disconnection of the cortical and subcortical centers. Very little work was done on aphasia in the 19th century in the Netherlands. Van Rhijn's thesis, from an aphasiological point of view of limited value, does show that the notions of "centers", "connections", and "disorders due to disconnections" were generally known before Wernicke, also in the Netherlands. Copyright © 2011 Elsevier Srl. All rights reserved.

Einsteins Spuren in den Archiven der Wissenschaft: Physikgeschichte

NASA Astrophysics Data System (ADS)

Marx, Werner

2005-07-01

Die Erwähnungen und Zitierungen von Einsteins Arbeiten dokumentieren lediglich den quantifizierbaren Anteil von Einsteins Beitrag zur Physik. Gleichwohl belegen sie die außergewöhnliche Resonanz und Langzeitwirkung seiner Arbeiten. Die Häufigkeit der Zitierungen entspricht nicht der allgemeinen Einschätzung ihrer Bedeutung. Insbesondere die Pionierarbeiten werden inzwischen als bekannt vorausgesetzt und nicht mehr explizit zitiert. Interessanterweise ist seine nach 1945 meist zitierte Arbeit nicht eine der Pionierarbeiten zur Quantenphysik oder Relativitätstheorie, sondern jene aus dem Jahr 1935 zum berühmten Einstein-Podolsky-Rosen-Paradoxon.

Moment tensor inversion of recent local moderate sized Van Earthquakes: seismicity and active tectonics of the Van region : Eastern Turkey

NASA Astrophysics Data System (ADS)

Kalafat, D.; Suvarikli, M.; Ogutcu, Z.; Kekovali, K.; Ocal, M. F.; Gunes, Y.; Pinar, A.

2013-12-01

The study area of the present research, the Van Region is located at the norththern end of the collision zone between the Anatolia and Arabian plates. Therefore, the southeast border of the Anatolian plate collides with the Arabian plate along the Bitlis Suture Zone. This zone is formed by collision of Arabian and in large scale Eurasian plates at mid-Miocen age. This type of thrust generation as a result of compressional regime extends east-west. The largest recorded earthquakes have all taken place along Southern Turkey (e.g. Lice, 1971; Varto, 1966; Caldiran, 1976). On the 23th of October 2011, an earthquake shook the Van Lake, Eastern Turkey, following a seismic sequence of more than three months in an unprecedented episode for this region characterized by null or low seismicity. The October 23, 2011 Van-Ercis Earthquake (Mw=7.1) was the most devastating resulting in loss of life and destruction. In order to study the aftershocks' activity of this main event, we installed and kept a seismic network of 10 broad-band (BB) stations in the area for an interval of nearly fifteen months. We characterized the seismogenic structure of the zone by calculating a minimum 1-D local velocity model and obtaining precise hypocentre locations. We also calculated fault plane solutions for more than 200 moderate sized earthquakes based on first motion polarities and commonly Moment Tensor Inversion Methods. The seismogenic zone would be localized at aproximately 10 km depth. Generally, the distribution of the important moderate earthquakes and the aftershock distribution shows that the E-W and NE-SW oriented fault segments cause the earthquake activities. Aftershock events are located along the eastern border of Lake Van and mainly between 5 and 10 km depth and disposed in two alignments: a ~E-W-trending alignment that matches with the trace of the Van Trust fault Zone and a NE-trending which could correspond to an structure not previously seen. Selected focal mechanisms show a

[Implementation of vanA and vanB genes by PCR technique research interest in system (Xpert vanA/vanB CepheidR) closed in a laboratory of microbiology in managing an outbreak to Enterococcus faecium resistant glycopeptide (EfRG)].

PubMed

Dekeyser, S; Beclin, E; Descamps, D

2011-04-01

The closed system PCR for the rapid detection of vanA and vanB genes (Xpert vanA/vanB Cepheid(®)) was evaluated in our laboratory, to improve the rapidity of the response and thus the management of patients and isolation measures during two GRE outbreaks. From March to December2009, 565 samples were analysed by PCR associated to bacterial culture initially for all samples for 2months (n = 75), and thereafter for PCR-positive samples only. In this study, sensitivity and negative predictive values of the PCR were 100%. Specificity was evaluated in the presence and absence of outbreak: 69.3 and 76.8% respectively. The variability of false positive rates between units were lower in nonepidemic than during epidemic phase. The global false positive rate was 23.9%. This easy-to-use technology provides rapid results… four samples are tested in 1h versus 72h for culture. Despite its reagent cost, it represents an important hospital diagnostic tool: improvement of the management of cohorting areas and patient transfer between units, adaptation of isolation measures and treatments. However, culture remains necessary to confirm any positive result obtained by PCR and for epidemiological surveillance. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Home range, den selection and habitat use of Carolina northern flying squirrels (Glaucomys sabrinus coloratus)

USGS Publications Warehouse

Diggins, Corinne A.; Silvis, Alexander; Kelly, Christine A.; Ford, W. Mark

2017-01-01

Context: Understanding habitat selection is important for determining conservation and management strategies for endangered species. The Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus) is an endangered subspecies found in the high-elevation montane forests of the southern Appalachians, USA. The primary use of nest boxes to monitor CNFS has provided biased information on habitat use for this subspecies, as nest boxes are typically placed in suitable denning habitat.Aims: We conducted a radio-telemetry study on CNFS to determine home range, den site selection and habitat use at multiple spatial scales.Methods: We radio-collared 21 CNFS in 2012 and 2014–15. We tracked squirrels to diurnal den sites and during night-time activity.Key results: The MCP (minimum convex polygon) home range at 95% for males was 5.2 ± 1.2 ha and for females was 4.0 ± 0.7. The BRB (biased random bridge) home range at 95% for males was 10.8 ± 3.8 ha and for females was 8.3 ± 2.1. Den site (n = 81) selection occurred more frequently in montane conifer dominate forests (81.4%) vs northern hardwood forests or conifer–northern hardwood forests (9.9% and 8.7%, respectively). We assessed habitat selection using Euclidean distance-based analysis at the 2nd order and 3rd order scale. We found that squirrels were non-randomly selecting for habitat at both 2nd and 3rd order scales.Conclusions: At both spatial scales, CNFS preferentially selected for montane conifer forests more than expected based on availability on the landscape. Squirrels selected neither for nor against northern hardwood forests, regardless of availability on the landscape. Additionally, CNFS denned in montane conifer forests more than other habitat types.Implications: Our results highlight the importance of montane conifer to CNFS in the southern Appalachians. Management and restoration activities that increase the quality, connectivity and extent of this naturally rare forest type may be

Effective field theories for van der Waals interactions

NASA Astrophysics Data System (ADS)

Brambilla, Nora; Shtabovenko, Vladyslav; Tarrús Castellà, Jaume; Vairo, Antonio

2017-06-01

Van der Waals interactions between two neutral but polarizable systems at a separation R much larger than the typical size of the systems are at the core of a broad sweep of contemporary problems in settings ranging from atomic, molecular and condensed matter physics to strong interactions and gravity. In this paper, we reexamine the dispersive van der Waals interactions between two hydrogen atoms. The novelty of the analysis resides in the usage of nonrelativistic effective field theories of quantum electrodynamics. In this framework, the van der Waals potential acquires the meaning of a matching coefficient in an effective field theory, dubbed van der Waals effective field theory, suited to describe the low-energy dynamics of an atom pair. It may be computed systematically as a series in R times some typical atomic scale and in the fine-structure constant α . The van der Waals potential gets short-range contributions and radiative corrections, which we compute in dimensional regularization and renormalize here for the first time. Results are given in d space-time dimensions. One can distinguish among different regimes depending on the relative size between 1 /R and the typical atomic bound-state energy, which is of order m α2. Each regime is characterized by a specific hierarchy of scales and a corresponding tower of effective field theories. The short-distance regime is characterized by 1 /R ≫m α2 and the leading-order van der Waals potential is the London potential. We also compute next-to-next-to-next-to-leading-order corrections. In the long-distance regime we have 1 /R ≪m α2. In this regime, the van der Waals potential contains contact terms, which are parametrically larger than the Casimir-Polder potential that describes the potential at large distances. In the effective field theory, the Casimir-Polder potential counts as a next-to-next-to-next-to-leading-order effect. In the intermediate-distance regime, 1 /R ˜m α2, a significantly more complex

Nonsurgical Management of an Immature Maxillary Central Incisor with Type III Dens Invaginatus Using MTA Plug: A Case Report

PubMed Central

Norouzi, Negar; Kazem, Majid; Gohari, Atefeh

2017-01-01

Dens invaginatus is a developmental anomaly, caused by deepening of the enamel organ into the dental papilla before calcification of the dental tissues. Teeth with dens invagination are susceptible to early caries and pulp necrosis within a few years of eruption or even before root end closure. This article reports two immature maxillary central incisors with type I and III dens invaginatus which had necrotic pulp and a large periradicular lesion, that were treated successfully by nonsurgical root canal treatment. After apical plug placement, the remaining space was backfilled using warm vertical gutta-percha technique and the crowns were restored by composite restoration. At 6 months of follow up the patient was asymptomatic and probing depths were less than 3 mm. In addition, the reduction in the size of apical radiolucencies was observed by radiographic examinations. This case report revealed that even type III des invaginatus with an open apex and large periapical lesion, can be treated non-surgically using MTA as an apical plug. Although this case report presents a favorable result, further studies with long term follow-up periods are encouraged to support the use of nonsurgical endodontic treatment for type III dens invaginatus. PMID:29225653

The Economics of van der Waals Force Engineering

NASA Astrophysics Data System (ADS)

Pinto, Fabrizio

2008-01-01

As micro-electro-mechanical system (MEMS) fabrication continues on an ever-decreasing scale, new technological challenges must be successfully negotiated if Moore's Law is to be an even approximately valid model of the future of device miniaturization. Among the most significant obstacles is the existence of strong surface forces related to quantum mechanical van der Waals interatomic interactions, which rapidly diverge as the distance between any two neutral boundaries decreases. The van der Waals force is a contributing factor in several device failures and limitations, including, for instance, stiction and oscillator non-linearities. In the last decade, however, it has been conclusively shown that van der Waals forces are not just a MEMS limitation but can be engineered in both magnitude and sign so as to enable classes of proprietary inventions which either deliver novel capabilities or improve upon existing ones. The evolution of van der Waals force research from an almost exclusively theoretical field in quantum-electro-dynamics to an enabling nanotechnology discipline represents a useful example of the ongoing paradigm shift from government-centered to private-capital funded R&D in cutting-edge physics leading to potentially profitable products. In this paper, we discuss the reasons van der Waals force engineering may lead to the creation of thriving markets both in the short and medium terms by highlighting technical challenges that can be competitively addressed by this novel approach. We also discuss some notable obstacles to the cultural transformation of the academic research community required for the emergence of a functional van der Waals force engineering industry worldwide.

Arthur van Gehuchten takes neurology to the movies.

PubMed

Aubert, Geneviève

2002-11-26

To present the cinematographic production of Arthur Van Gehuchten (1861-1914) and to put this collection into its medical and sociocultural context. The arrival of Edison's Kinetoscope (1891) and Lumière's Cinématographe (1895) provoked the immediate interest of neurologists who foresaw the potential of motion pictures for illustration, research, and teaching. Arthur Van Gehuchten, professor of anatomy and neurology at the Catholic University of Louvain, was trained as a microscopist and a cytologist. From neuroanatomy, he progressively broadened his interest to neurology. Van Gehuchten was an avant-garde teacher, eager to adopt new visual aids. In 1895, he attended the first cinematographic screenings. Medical cinematography was soon brought into disrepute in European academic circles, when films made by the French surgeon Doyen were copied and shown on fairgrounds. Nevertheless, in 1905, Van Gehuchten began to film neurologic patients. He used this technique extensively to demonstrate clinical signs, to illustrate neurologic diseases, and to document functional evolution following surgery. For decades, these films were screened for medical students by Van Gehuchten's successors to the chair of neurology. The original nitrate films (more than 2 hours) have been recently rediscovered. They have been restored by the Royal Belgian Film Archive, where they are the oldest Belgian films. At the beginning of the 20th century, Van Gehuchten built up a collection of moving pictures for teaching purposes. This was one of the first such undertakings. This unique set of films has miraculously survived, and serves as an important archive of nervous diseases and their manifestations prior to the advent of modern therapies.

Nodal Statistics for the Van Vleck Polynomials

NASA Astrophysics Data System (ADS)

Bourget, Alain

The Van Vleck polynomials naturally arise from the generalized Lamé equation as the polynomials of degree for which Eq. (1) has a polynomial solution of some degree k. In this paper, we compute the limiting distribution, as well as the limiting mean level spacings distribution of the zeros of any Van Vleck polynomial as N --> ∞.

Vehicle test report: Jet Industries Electra Van 600

NASA Technical Reports Server (NTRS)

Price, T. W.; Wirth, V. A., Jr.

1982-01-01

The Electra Van 600, an electric vehicle, was tested. Tests were performed to characterize parameters of the Electra Van 600 and to provide baseline data to be used for comparison of improved batteries and to which will be incorporated into the vehicle. The vehicle tests concentrated on the electrical drive subsystem, the batteries, controller, and motor; coastdowns to characterize the road load and range evaluation for cyclic and constant speed conditions; and qualitative performance was evaluated. It is found that the Electra Van 600 range performance is approximately equal to the majority of the vehicles tested previously.

A Trio of Brownian Donkeys

NASA Astrophysics Data System (ADS)

van den Broeck, C.; Cleuren, B.; Kawai, R.; Kambon, M.

A previously introduced model (B. Cleuren and C. Van den Broeck, Europhys. Lett. 54, 1 (2001)) is studied numerically. Pure negative mobility is found for the minimum number of three interacting walkers.

Scaling laws for van der Waals interactions in nanostructured materials.

PubMed

Gobre, Vivekanand V; Tkatchenko, Alexandre

2013-01-01

Van der Waals interactions have a fundamental role in biology, physics and chemistry, in particular in the self-assembly and the ensuing function of nanostructured materials. Here we utilize an efficient microscopic method to demonstrate that van der Waals interactions in nanomaterials act at distances greater than typically assumed, and can be characterized by different scaling laws depending on the dimensionality and size of the system. Specifically, we study the behaviour of van der Waals interactions in single-layer and multilayer graphene, fullerenes of varying size, single-wall carbon nanotubes and graphene nanoribbons. As a function of nanostructure size, the van der Waals coefficients follow unusual trends for all of the considered systems, and deviate significantly from the conventionally employed pairwise-additive picture. We propose that the peculiar van der Waals interactions in nanostructured materials could be exploited to control their self-assembly.

RpoS induces expression of the Vibrio anguillarum quorum-sensing regulator VanT.

PubMed

Weber, Barbara; Croxatto, Antony; Chen, Chang; Milton, Debra L

2008-03-01

In vibrios, regulation of the Vibrio harveyi-like LuxR transcriptional activators occurs post-transcriptionally via small regulatory RNAs (sRNAs) that destabilize the luxR mRNA at a low cell population, eliminating expression of LuxR. Expression of the sRNAs is modulated by the vibrio quorum-sensing phosphorelay systems. However, vanT mRNA, which encodes a LuxR homologue in Vibrio anguillarum, is abundant at low and high cell density, indicating that VanT expression may be regulated via additional mechanisms. In this study, Western analyses showed that VanT was expressed throughout growth with a peak of expression during late exponential growth. VanO induced partial destabilization of vanT mRNA via activation of at least one Qrr sRNA. Interestingly, the sigma factor RpoS significantly stabilized vanT mRNA and induced VanT expression during late exponential growth. This induction was in part due to RpoS repressing expression of Hfq, an RNA chaperone. RpoS is not part of the quorum-sensing regulatory cascade since RpoS did not regulate expression or activity of VanO, and RpoS was not regulated by VanO or VanT. VanT and RpoS were needed for survival following UV irradiation and for pigment and metalloprotease production, suggesting that RpoS works with the quorum-sensing systems to modulate expression of VanT, which regulates survival and stress responses.

A comparison of photograph-interpreted and IfSAR-derived maps of polar bear denning habitat for the 1002 Area of the Arctic National Wildlife Refuge, Alaska

USGS Publications Warehouse

Durner, George M.; Atwood, Todd C.

2018-05-11

Polar bears (Ursus maritimus) in Alaska use the Arctic National Wildlife Refuge (ANWR) for maternal denning. Pregnant bears den in snow banks for more than 3 months in winter during which they give birth to and nurture young. Denning is one of the most vulnerable times in polar bear life history as the family group cannot simply walk away from a disturbance without jeopardizing survival of newly born cubs. The ANWR includes the “1002 Area”, a region recently opened for oil and gas exploration by the U.S. Department of the Interior (DOI). As a part of its mission, the DOI “… protects and manages the Nation's natural resources …” and is therefore responsible for conserving polar bears and encouraging development of energy potential. Because future industrial activities could overlap habitats used by denning polar bears, identifying these habitats can inform the decisions of resource managers tasked to develop resources and protect polar bears. To help inform these efforts, we qualitatively compared the distribution of denning habitat identified by two different methods: previously published habitat from manual interpretation of aerial photographs, and habitat derived by computer interrogation of interferometric synthetic aperture radar (IfSAR) digital terrain models (DTM). Because photograph-interpreted methods depicted denning habitat as a line and IfSAR-derived methods depicted habitat as a polygon, we assessed agreement between the two methods with distance measurements. We found that 77.5 percent of IfSAR-derived denning habitat (79.6 km2 ; 1.2 percent of the 6,837.0 km2 1002 Area) was within 600 m of photograph-interpreted habitat (3,026.9 km), including 53.9 percent within 200 m. This distribution differed from that of randomly distributed points, as only 49.4 percent of these occurred within 600 m of photograph-interpreted habitat, including 18.3 percent within 200 m. Both methods appear to identify the major physiographic features that polar bears

van Manen's method and reduction in a phenomenological hermeneutic study.

PubMed

Heinonen, Kristiina

2015-03-01

To describe van Manen's method and concept of reduction in a study that used a phenomenological hermeneutic approach. Nurse researchers have used van Manen's method in different ways. Participants' lifeworlds are described in depth, but descriptions of reduction have been brief. The literature and knowledge review and manual search of research articles. Databases Web Science, PubMed, CINAHL and PsycINFO, without applying a time period, to identify uses of van Manen's method. This paper shows how van Manen's method has been used in nursing research and gives some examples of van Manen's reduction. Reduction enables us to conduct in-depth phenomenological hermeneutic research and understand people's lifeworlds. As there are many variations in adapting reduction, it is complex and confusing. This paper contributes to the discussion of phenomenology, hermeneutic study and reduction. It opens up reduction as a method for researchers to exploit.

Genomic and expression analysis of the vanG-like gene cluster of Clostridium difficile.

PubMed

Peltier, Johann; Courtin, Pascal; El Meouche, Imane; Catel-Ferreira, Manuella; Chapot-Chartier, Marie-Pierre; Lemée, Ludovic; Pons, Jean-Louis

2013-07-01

Primary antibiotic treatment of Clostridium difficile intestinal diseases requires metronidazole or vancomycin therapy. A cluster of genes homologous to enterococcal glycopeptides resistance vanG genes was found in the genome of C. difficile 630, although this strain remains sensitive to vancomycin. This vanG-like gene cluster was found to consist of five ORFs: the regulatory region consisting of vanR and vanS and the effector region consisting of vanG, vanXY and vanT. We found that 57 out of 83 C. difficile strains, representative of the main lineages of the species, harbour this vanG-like cluster. The cluster is expressed as an operon and, when present, is found at the same genomic location in all strains. The vanG, vanXY and vanT homologues in C. difficile 630 are co-transcribed and expressed to a low level throughout the growth phases in the absence of vancomycin. Conversely, the expression of these genes is strongly induced in the presence of subinhibitory concentrations of vancomycin, indicating that the vanG-like operon is functional at the transcriptional level in C. difficile. Hydrophilic interaction liquid chromatography (HILIC-HPLC) and MS analysis of cytoplasmic peptidoglycan precursors of C. difficile 630 grown without vancomycin revealed the exclusive presence of a UDP-MurNAc-pentapeptide with an alanine at the C terminus. UDP-MurNAc-pentapeptide [d-Ala] was also the only peptidoglycan precursor detected in C. difficile grown in the presence of vancomycin, corroborating the lack of vancomycin resistance. Peptidoglycan structures of a vanG-like mutant strain and of a strain lacking the vanG-like cluster did not differ from the C. difficile 630 strain, indicating that the vanG-like cluster also has no impact on cell-wall composition.

Van der waals forces on thin liquid films in capillary tubes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herdt, G.C.; Swanson, L.W.

1993-10-01

A theory of the van der Waals attraction between a thin liquid films and a capillary tube is presented assuming the presence of a vapor-liquid interface. The model is based on the surface mode analysis method of van Kampen et al. Values for the van der Waals interaction energy per unit area were calculated for liquid films of pentane on a gold substrate assuming a thin liquid film. Results indicate that the effect of capillary curvature on the van der Waals interaction increases as the ratio of the liquid film thickness to the capillary radius is increased. This trend ismore » consistent with predictions based on the Hamaker theory. Deviations from results based on the Hamaker theory are easily explained in terms of retardation of the van der Waals interaction. Because the effect of capillary curvature increases in the regime where retardation effects become important, curvature effects constitute a small correction to the van der Waals forces in a capillary tube.« less

Martin Van Buren National Historic Site transportation analysis report

DOT National Transportation Integrated Search

2010-10-01

The Volpe Transportation Systems Center (Volpe Center) is providing transportation support to Martin Van Buren National Historic Site's (NHS) first General Management Plan (GMP), which will be complete in 2010 or 2011. Currently, Martin Van Buren NHS...

Coexistence of true talon cusp and double dens invaginatus in a single tooth: a rare case report and review of the literature.

PubMed

Nu Nu Lwin, Hnin; Phyo Kyaw, Pyae; Wai Yan Myint Thu, Sai

2017-12-01

Co-occurrence of a talon cusp and double dens invaginatus is an extremely rare developmental dental anomaly. This case report represents a talon cusp with two dens invaginatus on a maxillary right lateral incisor. Early identification is needed for prevention of potential problems on the affected or opposing tooth.

Where to deliver baits for deworming urban red foxes for Echinococcus multilocularis control: new protocol for micro-habitat modeling of fox denning requirements.

PubMed

Ikeda, Takako; Yoshimura, Masashi; Onoyama, Keiichi; Oku, Yuzaburo; Nonaka, Nariaki; Katakura, Ken

2014-08-06

Deworming wild foxes by baiting with the anthelmintic praziquantel is being established as a preventive technique against environmental contamination with Echinococcus multilocularis eggs. Improvement of the cost-benefit performance of baiting treatment is required urgently to raise and maintain the efficacy of deworming. We established a spatial model of den site selection by urban red foxes, the definitive host, to specify the optimal micro-habitats for delivering baits in a new modeling approach modified for urban fox populations. The model was established for two cities (Obihiro and Sapporo) in Hokkaido, Japan, in which a sylvatic cycle of E. multilocularis is maintained. The two cities have different degrees of urbanization. The modeling process was designed to detect the best combination of key environmental factors and spatial scale that foxes pay attention to most (here named 'heeding range') when they select den sites. All possible models were generated using logistic regression analysis, with "presence" or "absence" of fox den as the objective variable, and nine landscape categories customized for urban environments as predictor variables to detect the best subset of predictors. This procedure was conducted for each of ten sizes of concentric circles from dens and control points to detect the best circle size. Out of all models generated, the most parsimonious model was selected using Akaike's Information Criterion (AIC) inspection. Our models suggest that fox dens in Obihiro are located at the center of a circle with 500 m radius including low percentages of wide roads, narrow roads, and occupied buildings, but high percentages of green covered areas; the dens in Sapporo within 300 m radius with low percentages of wide roads, occupied buildings, but high percentages of riverbeds and green covered areas. The variation of the models suggests the necessity of accumulating models for various types of cities in order to reveal the patterns of the model. Our

A Rare Bilateral Presentation of Multiple Dens Invaginatus, Shovel-Shaped Incisor and Talon Cusp With Mesiodens.

PubMed

Hegde, S; Jain, M; Shubha, A B

2014-01-01

The aim of this paper is to describe a unique and unusual case of concomitant appearance of morphological dental anomalies in the maxillary anterior region, along with its management in a patient with no systemic abnormality. This case report describes the clinical and radiographic features of talon cusp, dens invaginatus, shovel-shaped incisors and a supernumerary tooth occurring in a single patient, which is a rare presentation. All 4 permanent maxillary incisors had dens invaginatus, the permanent maxillary canines showed the presence of talon cusps, the permanent maxillary central incisors were shovel-shaped and an erupted mesiodens was also observed. Treatment included restorative, surgical and orthodontic approaches.

A. E. van Vogt: In Search of Meaning.

ERIC Educational Resources Information Center

Drake, H. L.

A general semantics perspective of science fiction writer A. E. van Vogt is presented in this paper. The first major section of the paper contains a biographical sketch of van Vogt and traces the influence of A. Korzybski's work on general semantics, "Science and Sanity," on his writing, while the second major section provides an…

Alkaptonuria

MedlinePlus

... unable to properly break down certain amino acids (tyrosine and phenylalanine). As a result, a substance called ... Chakrapani A, Gissen P, McKiernan P. Disorders of tyrosine metabolism. In: Saudubray J-M, van den Berghe ...

Status Report on Speech Research. A Report on the Status and Progress of Studies on the Nature of Speech, Instrumentation for Its Investigation, and Practical Applications.

DTIC Science & Technology

1983-01-01

Satoshi Horiguchi 2 Harriet Magen Leonard Katz’ Sharon Manuel J. A. Scott Kelso Richard McGowan Andrea G. Levitt’ Daniel Recasens Isabelle Y... Martinus Nijhoff, 1959. Collier, R., & ’t Hart, J. The perceptual relevance of formant trajectories in diphthongs. In M. van den Broecke & V. van Heuven...Studies in Dutch phonology (Dutch Studies, Vol. 4). The Hague: Martinus Nijhoff, 1980. FOOTNOTES Ipossible occurrences of these diphthongs in Dutch

Van Driest transformation and compressible wall-bounded flows

NASA Technical Reports Server (NTRS)

Huang, P. G.; Coleman, G. N.

1994-01-01

The transformation validity question utilizing resulting data from direct numerical simulations (DNS) of supersonic, isothermal cold wall channel flow was investigated. The DNS results stood for a wide scope of parameter and were suitable for the purpose of examining the generality of Van Driest transformation. The Van Driest law of the wall can be obtained from the inner-layer similarity arguments. It was demonstrated that the Van Driest transformation cannot be incorporated to collapse the sublayer and log-layer velocity profiles simultaneously. Velocity and temperature predictions according to the preceding composite mixing-length model were presented. Despite satisfactory congruity with the DNS data, the model must be perceived as an engineering guide and not as a rigorous analysis.

Alternative Fuels Data Center: Natural Gas Delivery Vans Support McShan

Science.gov Websites

FloristA> Natural Gas Delivery Vans Support McShan Florist to someone by E-mail Share Alternative Natural Gas Delivery Vans Support McShan Florist Watch how a Dallas, Texas, florist reduces emissions and saves money fueling delivery vans with compressed natural gas. For information about this project

Van de Hulst Essay: Light Scattering, Aerosols, Clouds, Climate, Hendrik van de Hulst, and I

DOE PAGES

Chylek, Petr

2017-12-06

It is not often that I have the opportunity to write something that is not a scientific study, and I am thankful for this opportunity to express my thoughts with regard to pursuits that are greater than those of science. In this van de Hulst assay, to honor Hendrik van de Hulst, I briefly summarize a few points from Hendrik's life that I find especially interesting, including his interests in spiritual (or religious) aspects of life, and his decision to avoid involvement in nucleation problems, a critical and basic uncertainty of current climate models. Finally, after that, I present brieflymore » a few episodes from my own experiences as an apprentice of science and life.« less

Van de Hulst Essay: Light Scattering, Aerosols, Clouds, Climate, Hendrik van de Hulst, and I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chylek, Petr

It is not often that I have the opportunity to write something that is not a scientific study, and I am thankful for this opportunity to express my thoughts with regard to pursuits that are greater than those of science. In this van de Hulst assay, to honor Hendrik van de Hulst, I briefly summarize a few points from Hendrik's life that I find especially interesting, including his interests in spiritual (or religious) aspects of life, and his decision to avoid involvement in nucleation problems, a critical and basic uncertainty of current climate models. Finally, after that, I present brieflymore » a few episodes from my own experiences as an apprentice of science and life.« less

Multiple Voices in Charles Van Riper's Desensitization Therapy

ERIC Educational Resources Information Center

Leahy, Margaret M.

2008-01-01

Background: Charles Van Riper (1905-94) author, researcher and practitioner, was one of the major contributors to the field of stuttering in the 20th century. His series of Action Therapy videotapes provide a useful model of how therapy was implemented by a master clinician. Aims: Van Riper's session with a client is analysed to reveal how voices…

The Influence of the Outdoor Environment: Den-Making in Three Different Contexts

ERIC Educational Resources Information Center

Canning, Natalie

2010-01-01

This small-scale research examined den-making in three different settings in the UK. The research consisted of non-participant, narrative observations of children aged between 3- and 5-years and early years practitioners involved in supporting them in their play. Content analysis revealed common themes: the impact of the environment on the way…

Van Gogh from Space

NASA Image and Video Library

2017-12-08

Van Gogh from Space - July 13th, 2005 Description: In the style of Van Gogh's painting "Starry Night," massive congregations of greenish phytoplankton swirl in the dark water around Gotland, a Swedish island in the Baltic Sea. Phytoplankton are microscopic marine plants that form the first link in nearly all ocean food chains. Population explosions, or blooms, of phytoplankton, like the one shown here, occur when deep currents bring nutrients up to sunlit surface waters, fueling the growth and reproduction of these tiny plants. Credit: USGS/NASA/Landsat 7 To learn more about the Landsat satellite go to: landsat.gsfc.nasa.gov/ NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Join us on Facebook

Multilevel population genetic analysis of vanA and vanB Enterococcus faecium causing nosocomial outbreaks in 27 countries (1986-2012).

PubMed

Freitas, Ana R; Tedim, Ana P; Francia, Maria V; Jensen, Lars B; Novais, Carla; Peixe, Luísa; Sánchez-Valenzuela, Antonio; Sundsfjord, Arnfinn; Hegstad, Kristin; Werner, Guido; Sadowy, Ewa; Hammerum, Anette M; Garcia-Migura, Lourdes; Willems, Rob J; Baquero, Fernando; Coque, Teresa M

2016-12-01

Vancomycin-resistant Enterococcus faecium (VREfm) have been increasingly reported since the 1980s. Despite the high number of published studies about VRE epidemiology, the dynamics and evolvability of these microorganisms are still not fully understood. A multilevel population genetic analysis of VREfm outbreak strains since 1986, representing the first comprehensive characterization of plasmid content in E. faecium, was performed to provide a detailed view of potential transmissible units. From a comprehensive MeSH search, we identified VREfm strains causing hospital outbreaks (1986-2012). In total, 53 VanA and 18 VanB isolates (27 countries, 5 continents) were analysed and 82 vancomycin-susceptible E. faecium (VSEfm) were included for comparison. Clonal relatedness was established by PFGE and MLST (goeBURST/Bayesian Analysis of Population Structure, BAPS). Characterization of van transposons (PCR mapping, RFLP, sequencing), plasmids (transfer, ClaI-RFLP, PCR typing of relaxases, replication-initiation proteins and toxin-antitoxin systems, hybridization, sequencing), bacteriocins and virulence determinants (PCR, hybridization, sequencing) was performed. VREfm were mainly associated with major human lineages ST17, ST18 and ST78. VREfm and VSEfm harboured plasmids of different families [RCR, small theta plasmids, RepA_N (pRUM/pLG1) and Inc18] able to yield mosaic elements. Tn1546-vanA was mainly located on pRUM/Axe-Txe (USA) and Inc18-pIP186 (Europe) plasmids. The VanB2 type (Tn5382/Tn1549) was predominant among VanB strains (chromosome and plasmids). Both strains and plasmids contributed to the spread and persistence of vancomycin resistance among E. faecium. Horizontal gene transfer events among genetic elements from different clonal lineages (same or different species) result in chimeras with different stability and host range, complicating the surveillance of epidemic plasmids. © The Author 2016. Published by Oxford University Press on behalf of the British

MATE (Mentale Aspecten van Team Effectiviteit) (MATE (Mental Aspects of Team Effectiveness))

DTIC Science & Technology

2008-05-01

0 Auteur (s) drs. J.P. van Meer drs. MI. 1 ’ IIart0 drs. 1. van der 16. Rubricering rapport Ongerubriceerd Vastgesteld door Ikol drs. L.A. de Vos...team Auteur (s) Teamntraining drs. J.P. van Meer drs. M.H.E. I Hart Programmanummer Projectnummer drs. 1. van der Beijl V406 015.34095 Rubricering...Murphy & Cleveland (1995) geven inzicht in de tearngedragingen die meetbaar zijn en de theorie over Shared Mental Models (Espevik et al, 2006) laat zien

Isotope separation by photodissociation of Van der Waal's molecules

DOEpatents

Lee, Yuan T.

1977-01-01

A method of separating isotopes based on the dissociation of a Van der Waal's complex. A beam of molecules of a Van der Waal's complex containing, as one partner of the complex, a molecular species in which an element is present in a plurality of isotopes is subjected to radiation from a source tuned to a frequency which will selectively excite vibrational motion by a vibrational transition or through electronic transition of those complexed molecules of the molecular species which contain a desired isotope. Since the Van der Waal's binding energy is much smaller than the excitational energy of vibrational motion, the thus excited Van der Waal's complex dissociate into molecular components enriched in the desired isotope. The recoil velocity associated with vibrational to translational and rotational relaxation will send the separated molecules away from the beam whereupon the product enriched in the desired isotope can be separated from the constituents of the beam.

De Ontwikkeling van een PBPK Model voor VX; Stand van Zaken V013-813 en 207C (The Development of a PBPK Model for VX: Status Report)

DTIC Science & Technology

2006-02-01

ing. H.C. Trap, dr. ir. M.J. van der werd zes maal gesproken over de Schans, ing. L.F. Chau, B.). Lander, invulling en de voortgang van het I.A. Cordia ...dr. ir. M.J. van der Schans, ing. L.F. Chau, J.P. Oostdijk, B.J. Lander, l.A. Cordia 25 TNO Defensie en Veiligheid, vestiging Rijswijk, Marketing en

Electrons in the Inner Van Allen Belt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reeves, Geoff

A recent study shows that the inner Van Allen belt has less radiation than previously believed. Observations from NASA’s Van Allen probes show the fastest, most energetic electrons in the inner radiation belt are actually much rarer and harder to find than scientists expected. This is good news for spacecraft that are orbiting in the region and can be damaged by high levels of radiation. The results will also help scientists better understand—and detect—effects from high-altitude nuclear explosions.

SensInDenT-Noncontact Sensors Integrated Into Dental Treatment Units.

PubMed

Teichmann, Daniel; Teichmann, Maren; Weitz, Philippe; Wolfart, Stefan; Leonhardt, Steffen; Walter, Marian

2017-02-01

This paper presents the first system design (SensInDenT) for noncontact cardiorespiratory monitoring during dental treatment. The system is integrated into a dental treatment unit, and combines sensors based on electromagnetic, optical, and mechanical coupling at different sensor locations. The measurement principles and circuits are described and a system overview is presented. Furthermore, a first proof of concept is provided by taking measurements in healthy volunteers under laboratory conditions.

Energy Sources for Soldier Modernisation Programme Systems (Overzicht van Ontwikkelingen op het Gebied van Draagbare Energieopslag en Energieopwekking)

DTIC Science & Technology

1999-12-01

9 . http://home.earthlink.net/-fradella/homepage.htm 10. http ://web.mit.edu/aeroastro/www/labs/GTL/research/micro/micro.html 11 . http://www.ecr.co.il...Meijer 7 LAS/DB&P/BO/OB&T taxv. aooi Jansen 8 LAS/DB&PIBO/OB 9 LAS/DB&P/BO/CIV 10 OGMAN/Externe plannen Infanterie 11 DM/C31 12 DM/COM 13 KPU-bedrijf 14...detailed specifications mentioned before. TNO-rapport TNO-MEP - R 99/490 9 van 51 Samenvatting In dit rapport wordt een eerste globale selectie gemaakt: van

The research contributions of Dr. Paul Van Deusen

Treesearch

Thomas B. Lynch; Francis A. Roesch; John Paul McTague; Jeffrey H. Gove; Gregory A. Reams; Aaron R. Weiskittel

2015-01-01

Dr. Paul Van Deusen’s recent passing concluded a rich 30+-year research career dedicated to development and implementation of quantitative methods for forestry and natural resources. Since the early part of his career as a biometrician with the USDA Forest Service Southern Research Station in the 1980s-1990s and continuing with his later employment at NCASI, Dr. Van...

Mapping Van

NASA Technical Reports Server (NTRS)

1994-01-01

A NASA Center for the Commercial Development of Space (CCDS) - developed system for satellite mapping has been commercialized for the first time. Global Visions, Inc. maps an area while driving along a road in a sophisticated mapping van equipped with satellite signal receivers, video cameras and computer systems for collecting and storing mapping data. Data is fed into a computerized geographic information system (GIS). The resulting amps can be used for tax assessment purposes, emergency dispatch vehicles and fleet delivery companies as well as other applications.

Combination immunotherapy with prostate GVAX and ipilimumab: safety and toxicity.

PubMed

Karan, Dev; Van Veldhuizen, Peter

2012-06-01

Evaluation of: van den Eertwegh AJ, Versluis J, van den Berg HP et al. Combined immunotherapy with granulocyte-macrophage colony-stimulating factor-transduced allogeneic prostate cancer cells and ipilimumab in patients with metastatic castration-resistant prostate cancer: a Phase 1 dose-escalation trial. Lancet Oncol. 13(5), 509 – 517 (2012). A significant interest in the development of therapeutic cancer vaccines over the last decade has led to an improvement in overall survival of cancer patients in several clinical trials. As a result, two active immunotherapy agents, sipuleucel-T and ipilimumab, have been approved by the US FDA for the treatment of prostate cancer and melanoma, respectively. GVAX(®) cellular vaccine (Cell Genesysis, Inc., CA, USA) is another active immunotherapy agent targeting prostate cancer and it has been well studied in various clinical trials. The current publication, by van den Eertwegh et al., demonstrated a combination of two active immunotherapy approaches, using GVAX and ipilimumab for the treatment of metastatic castration-resistant prostate cancer. While GVAX is designed to amplify the antitumor response specific to prostate cancer cells, ipilimumab contributes to T-cell activation. Thus, the authors presented the possibility of augmenting antitumor T-cell activity in two different ways. They successfully demonstrated a tolerable dose and safety profile of ipilimumab in combination with GVAX for patients with metastatic castration-resistant prostate cancer. However, further studies of such immunotherapy combinations and detailed analysis of their immunological effects are needed to observe clinical benefit.

Novel type of VanB2 teicoplanin-resistant hospital-associated Enterococcus faecium.

PubMed

Santona, Antonella; Paglietti, Bianca; Al-Qahtani, Ahmed A; Bohol, Marie Fe F; Senok, Abiola; Deligios, Massimo; Rubino, Salvatore; Al-Ahdal, Mohammed N

2014-08-01

Seven high-risk clones of vancomycin-resistant Enterococcus faecium (VREF) belonging to clonal complex 17 were identified using multilocus sequence typing (MLST) among clinical isolates from Saudi Arabia. Among these isolates, a new hospital-associated sequence type (ST795), VanB(2)-type teicoplanin-resistant strain was detected. Its unusual phenotype resulted from a new combination of mutations in the ddl, vanS and vanW genes, which confirmed the trend of evolution in VanB-type resistance. Furthermore, characteristics of adaptation and persistence in the hospital environment of ST795 were emphasised by the presence of genes and clusters recognised to be specific for hospital-associated VREF. Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Reale Gase, tiefe Temperaturen

NASA Astrophysics Data System (ADS)

Heintze, Joachim

Wir werden uns in diesem Kapitel zunächst mit der van der Waals'schen Zustandsgleichung befassen. In dieser Gleichung wird versucht, die Abweichungen, die reale Gase vom Verhalten idealer Gase zeigen, durch physikalisch motivierte Korrekturterme zu berücksichtigen. Es zeigt sich, dass die van derWaals-Gleichung geeignet ist, nicht nur die Gasphase, sondern auch die Phänomene bei der Verflüssigung von Gasen und den kritischen Punkt zu beschreiben.

Job Oriented Training ’Lessons Learned’

DTIC Science & Technology

2008-11-01

Job Oriented Training ’Lessons Learned’ Job Oriented Training (JOT), een vorm van trainen waarbij de cursist zelfstandig, zonder theorie vooraf...39 77 lnfo-DenV@tno.nl TNO-rapportnummer TNO-DV 2008 A447 Opdrachtnummer Datum november 2008 Auteur (s) drs. H.E. Stubbe dr. A.H. van der...onderlinge discussie over achterliggende overwegingen te stimuleren. Zij hebben op dat moment nog geen theorie aangeboden gekregen en zijn niet op de hoogte

Materials perspective on Casimir and van der Waals interactions

NASA Astrophysics Data System (ADS)

Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.; Rodriguez-Lopez, P.; Rodriguez, A. W.; Podgornik, R.

2016-10-01

Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. Such interactions are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insights into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. This review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. The outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.

Materials perspective on Casimir and van der Waals interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.

Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. In such interactions these are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insightsmore » into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. Our review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. Finally, the outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.« less

Materials perspective on Casimir and van der Waals interactions

DOE PAGES

Woods, L. M.; Dalvit, D. A. R.; Tkatchenko, A.; ...

2016-11-02

Interactions induced by electromagnetic fluctuations, such as van der Waals and Casimir forces, are of universal nature present at any length scale between any types of systems. In such interactions these are important not only for the fundamental science of materials behavior, but also for the design and improvement of micro- and nanostructured devices. In the past decade, many new materials have become available, which has stimulated the need for understanding their dispersive interactions. The field of van der Waals and Casimir forces has experienced an impetus in terms of developing novel theoretical and computational methods to provide new insightsmore » into related phenomena. The understanding of such forces has far reaching consequences as it bridges concepts in materials, atomic and molecular physics, condensed-matter physics, high-energy physics, chemistry, and biology. Our review summarizes major breakthroughs and emphasizes the common origin of van der Waals and Casimir interactions. Progress related to novel ab initio modeling approaches and their application in various systems, interactions in materials with Dirac-like spectra, force manipulations through nontrivial boundary conditions, and applications of van der Waals forces in organic and biological matter are examined. Finally, the outlook of the review is to give the scientific community a materials perspective of van der Waals and Casimir phenomena and stimulate the development of experimental techniques and applications.« less

van der Waals torque

NASA Astrophysics Data System (ADS)

Esquivel-Sirvent, Raul; Schatz, George

2014-03-01

The theory of generalized van der Waals forces by Lifshtz when applied to optically anisotropic media predicts the existence of a torque. In this work we present a theoretical calculation of the van der Waals torque for two systems. First we consider two isotropic parallel plates where the anisotropy is induced using an external magnetic field. The anisotropy will in turn induce a torque. As a case study we consider III-IV semiconductors such as InSb that can support magneto plasmons. The calculations of the torque are done in the Voigt configuration, that occurs when the magnetic field is parallel to the surface of the slabs. The change in the dielectric function as the magnetic field increases has the effect of decreasing the van der Waals force and increasing the torque. Thus, the external magnetic field is used to tune both the force and torque. The second example we present is the use of the torque in the non retarded regime to align arrays of nano particle slabs. The torque is calculated within Barash and Ginzburg formalism in the nonretarded limit, and is quantified by the introduction of a Hamaker torque constant. Calculations are conducted between anisotropic slabs of materials including BaTiO3 and arrays of Ag nano particles. Depending on the shape and arrangement of the Ag nano particles the effective dielectric function of the array can be tuned as to make it more or less anisotropic. We show how this torque can be used in self assembly of arrays of nano particles. ref. R. Esquivel-Sirvent, G. C. Schatz, Phys. Chem C, 117, 5492 (2013). partial support from DGAPA-UNAM.

Structural and Functional Adaptation of Vancomycin Resistance VanT Serine Racemases

PubMed Central

Meziane-Cherif, Djalal; Stogios, Peter J.; Evdokimova, Elena; Egorova, Olga

2015-01-01

ABSTRACT Vancomycin resistance in Gram-positive bacteria results from the replacement of the d-alanyl–d-alanine target of peptidoglycan precursors with d-alanyl–d-lactate or d-alanyl–d-serine (d-Ala-d-Ser), to which vancomycin has low binding affinity. VanT is one of the proteins required for the production of d-Ala-d-Ser-terminating precursors by converting l-Ser to d-Ser. VanT is composed of two domains, an N-terminal membrane-bound domain, likely involved in l-Ser uptake, and a C-terminal cytoplasmic catalytic domain which is related to bacterial alanine racemases. To gain insight into the molecular function of VanT, the crystal structure of the catalytic domain of VanTG from VanG-type resistant Enterococcus faecalis BM4518 was determined. The structure showed significant similarity to type III pyridoxal 5′-phosphate (PLP)-dependent alanine racemases, which are essential for peptidoglycan synthesis. Comparative structural analysis between VanTG and alanine racemases as well as site-directed mutagenesis identified three specific active site positions centered around Asn696 which are responsible for the l-amino acid specificity. This analysis also suggested that VanT racemases evolved from regular alanine racemases by acquiring additional selectivity toward serine while preserving that for alanine. The 4-fold-lower relative catalytic efficiency of VanTG against l-Ser versus l-Ala implied that this enzyme relies on its membrane-bound domain for l-Ser transport to increase the overall rate of d-Ser production. These findings illustrate how vancomycin pressure selected for molecular adaptation of a housekeeping enzyme to a bifunctional enzyme to allow for peptidoglycan remodeling, a strategy increasingly observed in antibiotic-resistant bacteria. PMID:26265719

Structural and functional adaptation of vancomycin resistance VanT serine racemases

DOE PAGES

Meziane-Cherif, Djalal; Stogios, Peter J.; Evdokimova, Elena; ...

2015-08-11

Vancomycin resistance in Gram-positive bacteria results from the replacement of the D-alanyl–D-alanine target of peptidoglycan precursors with D-alanyl–D-lactate or D-alanyl–D-serine (D-Ala-D-Ser), to which vancomycin has low binding affinity. VanT is one of the proteins required for the production of D-Ala-D-Ser-terminating precursors by converting L-Ser to D-Ser. VanT is composed of two domains, an N-terminal membrane-bound domain, likely involved in L-Ser uptake, and a C-terminal cytoplasmic catalytic domain which is related to bacterial alanine racemases. To gain insight into the molecular function of VanT, the crystal structure of the catalytic domain of VanT G from VanG-type resistant Enterococcus faecalis BM4518more » was determined. The structure showed significant similarity to type III pyridoxal 5'-phosphate (PLP)-dependent alanine racemases, which are essential for peptidoglycan synthesis. Comparative structural analysis between VanT G and alanine racemases as well as site-directed mutagenesis identified three specific active site positions centered around Asn 696 which are responsible for theL-amino acid specificity. This analysis also suggested that VanT racemases evolved from regular alanine racemases by acquiring additional selectivity toward serine while preserving that for alanine. The 4-fold-lower relative catalytic efficiency of VanT G against L-Ser versus L-Ala implied that this enzyme relies on its membrane-bound domain for L-Ser transport to increase the overall rate of D-Ser production. These findings illustrate how vancomycin pressure selected for molecular adaptation of a housekeeping enzyme to a bifunctional enzyme to allow for peptidoglycan remodeling, a strategy increasingly observed in antibiotic-resistant bacteria.« less

Evaluation Studies of the DEN-2/S-1 Vaccine.

DTIC Science & Technology

1981-08-01

1.0 3.0, L o 1 .0 I11 125 11111 1.4 n .6_t _ MICROCOPY RESOLUTION TEST CHART NATIONAL WII ALI 0 MF S’ANDAkLT, ,’I, A ;40- AD EVALUATION STUDIES OF THE...monkeys Vaccination DEN-2/S-l Vaccine /AE TlhACT ( i - ,ewr e e1 If .,ceweu7 amd Iderdtlfy by block number) A dengue-2 live virus vaccine was tested in...viremia was detected in control animals. Serological tests were pi.r- formed on sera taken on post infection days 30,56 and 90. HI tests revealed sero

Modified Van der Waals equation and law of corresponding states

NASA Astrophysics Data System (ADS)

Zhong, Wei; Xiao, Changming; Zhu, Yongkai

2017-04-01

It is well known that the Van der Waals equation is a modification of the ideal gas law, yet it can be used to describe both gas and liquid, and some important messages can be obtained from this state equation. However, the Van der Waals equation is not a precise state equation, and it does not give a good description of the law of corresponding states. In this paper, we expand the Van der Waals equation into its Taylor's series form, and then modify the fourth order expansion by changing the constant Virial coefficients into their analogous ones. Via this way, a more precise result about the law of corresponding states has been obtained, and the law of corresponding states can then be expressed as: in terms of the reduced variables, all fluids should obey the same equation with the analogous Virial coefficients. In addition, the system of 3 He with quantum effects has also been taken into consideration with our modified Van der Waals equation, and it is found that, for a normal system without quantum effect, the modification on ideal gas law from the Van der Waals equation is more significant than the real case, however, for a system with quantum effect, this modification is less significant than the real case, thus a factor is introduced in this paper to weaken or strengthen the modification of the Van der Waals equation, respectively.

Huntsville, Alabama, Volunteer Van Demonstration

DOT National Transportation Integrated Search

1988-04-01

The Huntsville Volunteer Van Demonstration, operational since November of 1980, provides transportation service to the traditional transit-dependent community in an unconventional way. The city of Huntsville is not served by a conventional public tra...

The Selection of a Van Lift or a Scooter.

ERIC Educational Resources Information Center

Stevens, John H.

1990-01-01

This newsletter issue describes 3-wheeled scooters and van lifts that can assist a person with a disability to drive independently or have access to transportation. The section on van lifts compares hydraulic lifts and electric lifts, lists manufacturers, and offers an "assessment quiz" outlining factors to consider in selecting a van…

Thickened boundary layer theory for air film drag reduction on a van body surface

NASA Astrophysics Data System (ADS)

Xie, Xiaopeng; Cao, Lifeng; Huang, Heng

2018-05-01

To elucidate drag reduction mechanism on a van body surface under air film condition, a thickened boundary layer theory was proposed and a frictional resistance calculation model of the van body surface was established. The frictional resistance on the van body surface was calculated with different parameters of air film thickness. In addition, the frictional resistance of the van body surface under the air film condition was analyzed by computational fluid dynamics (CFD) simulation and different air film states that influenced the friction resistance on the van body surface were discussed. As supported by the CFD simulation results, the thickened boundary layer theory may provide reference for practical application of air film drag reduction on a van body surface.

A cost-effective traffic data collection system based on the iDEN mobile telecommunication network.

DOT National Transportation Integrated Search

2008-10-01

This report describes a cost-effective data collection system for Caltrans 170 traffic signal : controller. The data collection system is based on TCP/IP communication over existing : low-cost mobile communication networks and Motorola iDEN1 mobile...

Genetics Home Reference: Axenfeld-Rieger syndrome

MedlinePlus

... Claerhout I, Kroes HY, Plomp A, Arens YH, de Ravel T, Casteels I, De Jaegere S, Hooghe S, Wuyts W, van den Ende J, ... Knol HE, Oldenburg RA, Giltay J, Verheij JB, de Faber JT, Menten B, De Paepe A, Kestelyn ...

Pythagoras Meets Van Hiele.

ERIC Educational Resources Information Center

Flores, Alfinio

1993-01-01

Develops the Pythagorean Theorem in the context of the Van Hiele levels by presenting activities appropriate for each level. Activities point to preparatory development (level 0), give 3 different versions of Euclid's proof (levels 1, 2, and 3), give some generalizations of the theorem (level 3), and explore the Pythagorean relationship in other…

Learning mathematics in two dimensions: a review and look ahead at teaching and learning early childhood mathematics with children's literature.

PubMed

Flevares, Lucia M; Schiff, Jamie R

2014-01-01

In the past 25 years an identifiable interest in using children's literature in mathematics learning emerged (Clyne and Griffiths, 1991; Welchman-Tischler, 1992; Hong, 1996; Hellwig etal., 2000; Haury, 2001). We critically review the rationales given for the use of picture books in mathematics learning, with a special focus on geometry due to its underrepresentation in this body of literature and the need for greater focus on this topic. The benefits and effectiveness of using picture books for children's mathematics learning and interest have been documented (Hong, 1996; O'Neill etal., 2004; Young-Loveridge, 2004). For geometry, although much learning of shape ideas should be hands-on, two-dimensional figures are essential to develop children's understanding of plane geometry. Books may effectively engage pre-literate children with plane shapes (van den Heuvel-Panhuizen and van den Boogaard, 2008; Skoumpourdi and Mpakopoulou, 2011) and shapes as gestalt wholes or prototypes (van Hiele, 1986; Clements etal., 1999; Hannibal, 1999). We review several guidelines and evaluative criteria for book selection, including Cianciolo (2000), Schiro (1997), Hunsader (2004), and van den Heuvel-Panhuizen and Elia (2012). Geometry concepts have proven challenging for young students, but their difficulties may stem, in part, from inadequate teacher training and professional development (Clements and Sarama, 2000; Chard etal., 2008) which lead to misconceptions (Oberdorf and Taylor-Cox, 1999; Inan and Dogan-Temur, 2010). Using picture books in teacher training may be an inviting way for early childhood teachers to enhance their own knowledge. We will examine the literature for guidance on incorporating children's literature into teacher training. In closing we will outline a comprehensive, multi-pronged agenda for best instructional practices for selection and use of children's books in mathematics activities and for teacher training.

Learning mathematics in two dimensions: a review and look ahead at teaching and learning early childhood mathematics with children’s literature

PubMed Central

Flevares, Lucia M.; Schiff, Jamie R.

2014-01-01

In the past 25 years an identifiable interest in using children’s literature in mathematics learning emerged (Clyne and Griffiths, 1991; Welchman-Tischler, 1992; Hong, 1996; Hellwig etal., 2000; Haury, 2001). We critically review the rationales given for the use of picture books in mathematics learning, with a special focus on geometry due to its underrepresentation in this body of literature and the need for greater focus on this topic. The benefits and effectiveness of using picture books for children’s mathematics learning and interest have been documented (Hong, 1996; O’Neill etal., 2004; Young-Loveridge, 2004). For geometry, although much learning of shape ideas should be hands-on, two-dimensional figures are essential to develop children’s understanding of plane geometry. Books may effectively engage pre-literate children with plane shapes (van den Heuvel-Panhuizen and van den Boogaard, 2008; Skoumpourdi and Mpakopoulou, 2011) and shapes as gestalt wholes or prototypes (van Hiele, 1986; Clements etal., 1999; Hannibal, 1999). We review several guidelines and evaluative criteria for book selection, including Cianciolo (2000), Schiro (1997), Hunsader (2004), and van den Heuvel-Panhuizen and Elia (2012). Geometry concepts have proven challenging for young students, but their difficulties may stem, in part, from inadequate teacher training and professional development (Clements and Sarama, 2000; Chard etal., 2008) which lead to misconceptions (Oberdorf and Taylor-Cox, 1999; Inan and Dogan-Temur, 2010). Using picture books in teacher training may be an inviting way for early childhood teachers to enhance their own knowledge. We will examine the literature for guidance on incorporating children’s literature into teacher training. In closing we will outline a comprehensive, multi-pronged agenda for best instructional practices for selection and use of children’s books in mathematics activities and for teacher training. PMID:24904475

Wie verstehen Schülerinnen und Schüler den Begriff der Unendlichkeit?

NASA Astrophysics Data System (ADS)

Schimmöller, Tabea

Wie Hilbert bereits feststellte, wirkt die Idee der Unendlichkeit, wie keine andere, schon seit Zeiten sehr anregend und fruchtbar auf den Verstand und bewegt das Gemüt der Menschen. Der Begriff der Unendlichkeit bedarf aber auch, wie kein anderer, der Aufklärung, denn mit ihm eröffnet sich ein weites Feld, welches nicht nur aus vielen verschiedenen Definitionen besteht, sondern auch aus völlig unterschiedlichen Disziplinen. Physiker suchen immer dringender nach einer "Theorie für Alles" oder einer "Weltformel", Kosmologen beschäftigen sich unter anderem mit der Ewigkeit des Universums, Theologen interessiert eher die Unendlichkeit Gottes, Philosophen diskutieren unter anderem Grenzfragen zwischen Naturwissenschaft und Philosophie und die Mathematiker versuchen den Paradoxien des Unendlichen einen Sinn zu geben. Und so wird ersichtlich, dass nichts abstrakter ist als das Unendliche: Obwohl die Unendlichkeit für die unterschiedlichsten Wissenschaften von großer Bedeutung ist, "[ist] in der Wirklichkeit das Unendliche nirgends zu finden, [egal] was für Erfahrungen und Beobachtungen und welcherlei Wissenschaft wir auch heranziehen".

Partial complementation of the UV sensitivity of E. coli and yeast excision repair mutants by the cloned denV gene of bacteriophage T4.

PubMed

Chenevert, J M; Naumovski, L; Schultz, R A; Friedberg, E C

1986-04-01

The denV gene of bacteriophage T4 was reconstituted from two overlapping DNA fragments cloned in M13 vectors. The coding region of the intact gene was tailored into a series of plasmid vectors containing different promoters suitable for expression of the gene in E. coli and in yeast. Induction of the TAC promoter with IPTG resulted in overexpression of the gene, which was lethal to E. coli. Expression of the TACdenV gene in the absence of IPTG, or the use of the yeast GAL1 or ADH promoters resulted in partial complementation of the UV sensitivity of uvrA, uvrB, uvrC and recA mutants of E. coli and rad1, rad2, rad3, rad4 and rad10 mutants of S. cerevisiae. The extent of denV-mediated reactivation of excision-defective mutants was approximately equal to that of photoreactivation of such strains. Excision proficient E. coli cells transformed with a plasmid containing the denV gene were slightly more resistant to ultraviolet (UV) radiation than control cells without the denV gene. On the other hand, excision proficient yeast cells were slightly more sensitive to killing by UV radiation following transformation with a plasmid containing the denV gene. This effect was more pronounced in yeast mutants of the RAD52 epistasis group.

Structural and Functional Adaptation of Vancomycin Resistance VanT Serine Racemases.

PubMed

Meziane-Cherif, Djalal; Stogios, Peter J; Evdokimova, Elena; Egorova, Olga; Savchenko, Alexei; Courvalin, Patrice

2015-08-11

Vancomycin resistance in Gram-positive bacteria results from the replacement of the D-alanyl-D-alanine target of peptidoglycan precursors with D-alanyl-D-lactate or D-alanyl-D-serine (D-Ala-D-Ser), to which vancomycin has low binding affinity. VanT is one of the proteins required for the production of D-Ala-D-Ser-terminating precursors by converting L-Ser to D-Ser. VanT is composed of two domains, an N-terminal membrane-bound domain, likely involved in L-Ser uptake, and a C-terminal cytoplasmic catalytic domain which is related to bacterial alanine racemases. To gain insight into the molecular function of VanT, the crystal structure of the catalytic domain of VanTG from VanG-type resistant Enterococcus faecalis BM4518 was determined. The structure showed significant similarity to type III pyridoxal 5'-phosphate (PLP)-dependent alanine racemases, which are essential for peptidoglycan synthesis. Comparative structural analysis between VanTG and alanine racemases as well as site-directed mutagenesis identified three specific active site positions centered around Asn696 which are responsible for the L-amino acid specificity. This analysis also suggested that VanT racemases evolved from regular alanine racemases by acquiring additional selectivity toward serine while preserving that for alanine. The 4-fold-lower relative catalytic efficiency of VanTG against L-Ser versus L-Ala implied that this enzyme relies on its membrane-bound domain for L-Ser transport to increase the overall rate of d-Ser production. These findings illustrate how vancomycin pressure selected for molecular adaptation of a housekeeping enzyme to a bifunctional enzyme to allow for peptidoglycan remodeling, a strategy increasingly observed in antibiotic-resistant bacteria. Vancomycin is one of the drugs of last resort against Gram-positive antibiotic-resistant pathogens. However, bacteria have evolved a sophisticated mechanism which remodels the drug target, the D-alanine ending precursors in cell wall

REMOTE LAND MINE(FIELD) DETECTION. An Overview of Techniques (DETECTIE VAN LANDMIJNEN EN MIJNENVELDEN OP AFSTAND. Een Overzicht van de technieken),

DTIC Science & Technology

1994-09-01

titel DETECTIE VAN LANDMIJNEN EN MIJNENVELDEN OP AFSTAND, een overzicht van de technieken auteur (s) Drs. J.S. Groot, Ir. Y.H.L. Janssen datum september...functions based on set theory . The fundamental theory is developed in the sixties. This theory was applicable to binary images (black-and-white images...held at TNO-FEL. Various subjects related to fusion techniques: Dempster Shafer theory , Bayesian inference, Kalman filtering, fuzzy logic. [A15], [B4

Evolution of alkaline lakes - Lake Van case study

NASA Astrophysics Data System (ADS)

Tillman Meyer, Felix; Viehberg, Finn; Bahroun, Sonya; Wolf, Annabel; Immenhauser, Adrian; Kwiecien, Ola

2017-04-01

Lake Van in Eastern Anatolia (Turkey) is the largest terminal soda lake on Earth. The lake sedimentary profile covers ca. 600 ka (Stockhecke et al. 2014) Based on lithological changes, the presence of freshwater microfossils and close-to-freshwater pH value in the pore water, members of ICDP PALEOVAN concluded that Lake Van might have started as an open lake. Here we show paleontological and geochemical evidence in favour of this idea and constrain the time, when Lake Van likely transformed into a closed lake. Additionally we provide the first conceptual model of how this closure may have happened. Our archives of choice are inorganic and biogenic carbonates, separated by wet sieving. We identified microfossil assemblages (fraction > 125 µm) and performed high-resolution oxygen isotope (delta18O) and elemental (Mg/Ca, Sr/Ca) analyses of the fraction < 63 µm assuming that it represents only carbonates precipitating in the water column. Microfossil assemblage consists of three different species of ostracods (Candona spp, Loxoconcha sp, Amnicythere spp.), diatoms, gastropods and bivalves. Brakish-water ostracods, Loxoconcha sp and Amnicythere sp occur more often after 530 ka. Additionaly, Loxoconcha sp is a shallow-water species relaying on plants growing in the photic zone as food supply. These two aspects point to an increasing salinity in a shallowing lake. The delta18O values of inorganic carbonates are relatively low during the initial phase of Lake Van and increase abruptly (ca. 7‰) after 530 ka BP. At approximately the same time combination of Sr/Ca and Mg/Ca data suggest first occurrence of aragonite. Again, these findings suggest geochemical changes of the lake water concurrent with transition documented by microfossils. Comparison between Lake Van and Lake Ohrid (Lacey et al. 2016) delta18O data, precludes regional climate change (e.g.: increased evaporation) as the main driver of observed changes. With no evidence for increased volcanic or tectonic

Reconnaissance study of late quaternary faulting along cerro GoDen fault zone, western Puerto Rico

USGS Publications Warehouse

Mann, P.; Prentice, C.S.; Hippolyte, J.-C.; Grindlay, N.R.; Abrams, L.J.; Lao-Davila, D.

2005-01-01

The Cerro GoDen fault zone is associated with a curvilinear, continuous, and prominent topographic lineament in western Puerto Rico. The fault varies in strike from northwest to west. In its westernmost section, the fault is ???500 m south of an abrupt, curvilinear mountain front separating the 270- to 361-m-high La CaDena De San Francisco range from the Rio A??asco alluvial valley. The Quaternary fault of the A??asco Valley is in alignment with the bedrock fault mapped by D. McIntyre (1971) in the Central La Plata quadrangle sheet east of A??asco Valley. Previous workers have postulated that the Cerro GoDen fault zone continues southeast from the A??asco Valley and merges with the Great Southern Puerto Rico fault zone of south-central Puerto Rico. West of the A??asco Valley, the fault continues offshore into the Mona Passage (Caribbean Sea) where it is characterized by offsets of seafloor sediments estimated to be of late Quaternary age. Using both 1:18,500 scale air photographs taken in 1936 and 1:40,000 scale photographs taken by the U.S. Department of Agriculture in 1986, we iDentified geomorphic features suggestive of Quaternary fault movement in the A??asco Valley, including aligned and Deflected drainages, apparently offset terrace risers, and mountain-facing scarps. Many of these features suggest right-lateral displacement. Mapping of Paleogene bedrock units in the uplifted La CaDena range adjacent to the Cerro GoDen fault zone reveals the main tectonic events that have culminated in late Quaternary normal-oblique displacement across the Cerro GoDen fault. Cretaceous to Eocene rocks of the La CaDena range exhibit large folds with wavelengths of several kms. The orientation of folds and analysis of fault striations within the folds indicate that the folds formed by northeast-southwest shorTening in present-day geographic coordinates. The age of Deformation is well constrained as late Eocene-early Oligocene by an angular unconformity separating folDed, Deep

Combination Vancomycin/Cefazolin (VAN/CFZ) for Methicillin-Resistant Staphylococcus aureus (MRSA) Bloodstream Infections (BSI)

PubMed Central

Trinh, Trang D; Zasowski, Evan J; Lagnf, Abdalhamid M; Bhatia, Sahil; Dhar, Sorabh; Mynatt, Ryan; Pogue, Jason M; Rybak, Michael J

2017-01-01

Abstract Background VAN remains the standard for MRSA BSI but has been associated with treatment failures and resulted in prolonged BSI durations and recurrences. In vitro studies of VAN/CFZ against MRSA demonstrated synergy and prevention of VAN resistance. However, clinical use of VAN/CFZ has not been reported. The objective of this study was to compare patient outcomes treated with VAN/CFZ vs. VAN for MRSA BSI. Methods This was a retrospective, cohort, comparative-effectiveness study of hospitalized adults ≥18y with ≥1 MRSA blood culture and received VAN/CFZ combination for ≥24h or VAN alone initiated within 72h of index infection between 1/1/08 and 5/1/17. Patients who received >24h β-lactams other than CFZ, MRSA-active antibiotics other than VAN, with polymicrobial BSI, or had a second MRSA BSI episode during the study period were excluded. The primary composite failure outcome included: 30d mortality, MRSA BSI ≥7d, and 60d recurrence. Demographics were compared by Χ2, Fisher’s exact, Student’s t, or Mann–Whitney U tests. Multivariable regression models compared outcomes between the two treatment groups. Covariates with p-values ≤0.2 in bivariate analyses were included in the model. Results A total of 101 patients were included (CFZ/VAN = 41, VAN = 60). Demographics were similar except VAN patients were older (mean (±SD) age 58 (±14) v. 51 (±18) y, P = 0.04), had higher median (IQR) Charlson Comorbidity Index (3 (2-5) v. 1 (0–4), P < 0.01), APACHE II scores (13 (8-18) v. 11 (8-18), P = 0.2), and more endocarditis BSI source (37% v. 20%, P = 0.06). After accounting for BSI source, VAN/CFZ (adjusted odds ratio [aOR], 95% confidence intervals [CI], 0.33, 0.13-0.83) and low APACHE II scores (aOR 1.07, 95% CI 1–1.15) were independently associated with fewer failures. Bivariate outcomes are in table below: Variable, n (%) VAN/CFZ VAN P value Composite failure 10 (24) 31 (52) 0.006 30d mortality 3 (7.3) 5 (8.3) 1 BSI ≥7d 6 (15

Detection of seasonal asymptomatic dermatophytes in Van cats.

PubMed

Ilhan, Ziya; Karaca, Mehmet; Ekin, Ismail Hakki; Solmaz, Hasan; Akkan, Hasan Altan; Tutuncu, Mehmet

2016-01-01

The Van cat is a domestic landrace found in the Van province of eastern Turkey. In this study, we aimed to determine the seasonal carriage of dermatophytes in Van cats without clinical lesions. A total of 264 hair specimens were collected from clinically healthy cats in and around the Van Province. Of these samples, 30.3% were obtained in spring, 30.6% in summer, 16.6% in autumn, and 22.3% in winter; 45.1% of samples were from male cats and the rest from female ones. Of the studied cats, 118 were younger than 1 year, 78 were 1-3 years old, and 68 were older than 3 years. The specimens were subjected to direct microscopic examination with 15% potassium hydroxide and cultured on Sabouraud dextrose agar and dermatophyte test medium supplemented with cycloheximide and chloramphenicol. Dermatophyte identification was carried out based on macroscopic and microscopic colony morphology, urease activities, in vitro hair perforation test, growth at 37°C, and pigmentation on corn meal agar. Dermatophytes were isolated from 19 (7.1%) of the 264 specimens examined. The most frequently isolated fungi were Trichophyton terrestre (4.1%), followed by Microsporum gypseum (1.1%), M. nanum (1.1%), and T. mentagrophytes (0.7%), and these fungi may represent a health risk for humans in contact with clinically healthy Van cats. M. canis was not isolated from any of the specimens. Our results show no significant (p>0.05) association between carriage of dermatophytes and the gender of cats. The carriage rate of dermatophytes was high in spring and winter, and the only possible risk factor for infection was age of the animal. Copyright © 2015 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

New Results About the Earth’s Van Allen Radiation Belts

NASA Astrophysics Data System (ADS)

Baker, Daniel

2015-01-01

The first great scientific discovery of the Space Age was that the Earth is enshrouded in toroids, or 'belts', of very high-energy magnetically trapped charged particles. Early observations of the radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. Subsequent studies showed that electrons in the energy range 100 keV < E< 1 MeV often populated both the inner and outer zones with a pronounced 'slot' region relatively devoid of energetic electrons existing between them. This two-belt structure for the Van Allen moderate-energy electron component was explained as being due to strong interactions of electrons with electromagnetic waves just inside the cold plasma (plasmapause) boundary. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. However, recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed wholly unexpected properties of the radiation belts, especially at highly relativistic (E > 2 MeV) and ultra-relativistic (E > 5 MeV) kinetic energies. In this presentation we show using high spatial and temporal resolution data from the Relativistic Electron-Proton Telescope (REPT) experiment on board the Van Allen Probes that multiple belts can exist concurrently and that an exceedingly sharp inner boundary exists for ultra-relativistic electrons. Using additionally available Van Allen Probes data, we demonstrate that these remarkable features of energetic electrons are not due to a physical boundary within Earth's intrinsic magnetic field. Neither is it likely that human-generated electromagnetic transmitter wave fields might produce such effects. Rather, we conclude from these unique measurements that slow natural inward radial diffusion combined with weak, but persistent, wave-particle pitch angle

Otto Van Geet | NREL

Science.gov Websites

Center at NREL. Otto has been involved in the design, construction, and operation of energy efficient energy use campus and community design. Mr. Van Geet was one of the founding members of the Labs21 and assessment, passive solar building design, use of design tools, photovoltaic (PV) system design

Enhanced Chiral Discriminatory van der Waals Interactions Mediated by Chiral Surfaces

NASA Astrophysics Data System (ADS)

Barcellona, Pablo; Safari, Hassan; Salam, A.; Buhmann, Stefan Yoshi

2017-05-01

We predict a discriminatory interaction between a chiral molecule and an achiral molecule which is mediated by a chiral body. To achieve this, we generalize the van der Waals interaction potential between two ground-state molecules with electric, magnetic, and chiral response to nontrivial environments. The force is evaluated using second-order perturbation theory with an effective Hamiltonian. Chiral media enhance or reduce the free interaction via many-body interactions, making it possible to measure the chiral contributions to the van der Waals force with current technology. The van der Waals interaction is discriminatory with respect to enantiomers of different handedness and could be used to separate enantiomers. We also suggest a specific geometric configuration where the electric contribution to the van der Waals interaction is zero, making the chiral component the dominant effect.

Assessments of Intellectually Gifted Students With(out) Characteristic(s) of ASD: An Explorative Evaluation among Diagnosticians in Various Psycho-Educational Organisations

ERIC Educational Resources Information Center

Burger-Veltmeijer, Agnes E. J.; Minnaert, Alexander E. M. G.; van den Bosch, Els J.

2015-01-01

Recently, Burger-Veltmeijer, Minnaert & Van den Bosch (2014) constructed a conceptual framework, called the Strengths and Weaknesses Heuristic ("S&W Heuristic") which might provide systematicity and coherence in research as well as psycho-educational praxis, regarding assessments of Intellectually Gifted (IG) students with…

Jacobus Schroeder van der Kolk (1797-1862): his resistance against materialism.

PubMed

Eling, P

1998-07-01

Schroeder van der Kolk is regarded as the founder of Dutch psychiatry and neurology. This paper describes his vitalistic views on the relation between body and soul, as formulated by him in a series of lectures. These lectures were intended to counteract the materialistic tendencies of some of Schroeder van der Kolk's French and German contemporaries. It is argued that Schroeder van der Kolk can be regarded as the transition in Holland from the "Naturphilosophie" approach to the modern experimental approach in physiology. Copyright 1998 Academic Press.

Fundacion Bernard van Leer, Boletin Informativo, 1987-1996 (Bernard van Leer Foundation Information Bulletin).

ERIC Educational Resources Information Center

Fundacion Bernard van Leer, Boletin Informativo, 1996

1996-01-01

This document consists of ten annual Spanish Language Bulletins, published during the period 1987-1996. The early bulletins were largely composed of selections originally published in the Bernard van Lear Foundation's English-Language "Newsletter The articles discuss topics such as: (1) parents as children's first teachers; (2) health and…

Biochemical and Genetic Characterization of the vanC-2 Vancomycin Resistance Gene Cluster of Enterococcus casseliflavus ATCC 25788

PubMed Central

Dutta, Ireena; Reynolds, Peter E.

2002-01-01

The vanC-2 cluster of Enterococcus casseliflavus ATCC 25788 consisted of five genes (vanC-2, vanXYC-2, vanTC-2, vanRC-2, and vanSC-2) and shared the same organization as the vanC cluster of E. gallinarum BM4174. The proteins encoded by these genes displayed a high degree of amino acid identity to the proteins encoded within the vanC gene cluster. The putative d,d-dipeptidase-d,d-carboxypeptidase, VanXYC-2, exhibited 81% amino acid identity to VanXYC, and VanTC-2 displayed 65% amino acid identity to the serine racemase, VanT. VanRC-2 and VanSC-2 displayed high degrees of identity to VanRC and VanSC, respectively, and contained the conserved residues identified as important to their function as a response regulator and histidine kinase, respectively. Resistance to vancomycin was expressed inducibly in E. casseliflavus ATCC 25788 and required an extended period of induction. Analysis of peptidoglycan precursors revealed that UDP-N-acetylmuramyl-l-Ala-δ-d-Glu-l-Lys-d-Ala-d-Ser could not be detected until several hours after the addition of vancomycin, and its appearance coincided with the resumption of growth. The introduction of additional copies of the vanTC-2 gene, encoding a putative serine racemase, and the presence of supplementary d-serine in the growth medium both significantly reduced the period before growth resumed after addition of vancomycin. This suggested that the availability of d-serine plays an important role in the induction process. PMID:12234834

The first report of the vanC₁ gene in Enterococcus faecium isolated from a human clinical specimen.

PubMed

Sun, Mingyue; Wang, Yue; Chen, Zhongju; Zhu, Xuhui; Tian, Lei; Sun, Ziyong

2014-09-01

The vanC₁ gene, which is chromosomally located, confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Enterococcus faecium TJ4031 was isolated from a blood culture and harbours the vanC₁gene. Polymerase chain reaction (PCR) assays were performed to detect vanXYc and vanTc genes. Only the vanXYc gene was found in the E. faecium TJ4031 isolate. The minimum inhibitory concentrations of vancomycin and teicoplanin were 2 µg/mL and 1 µg/mL, respectively. Real-time reverse transcription-PCR results revealed that the vanC₁ and vanXYc genes were not expressed. Pulsed-field gel electrophoresis and southern hybridisation results showed that the vanC₁ gene was encoded in the chromosome. E. faecalis isolated from animals has been reported to harbour vanC₁gene. However, this study is the first to report the presence of the vanC₁gene in E. faecium of human origin. Additionally, our research showed the vanC₁gene cannot serve as a species-specific gene of E. gallinarum and that it is able to be transferred between bacteria. Although the resistance marker is not expressed in the strain, our results showed that E. faecium could acquire the vanC₁gene from different species.

NASA's Van Allen Probes Discover a Surprise Circling Earth

NASA Image and Video Library

2017-12-08

Two giant swaths of radiation, known as the Van Allen Belts, surrounding Earth were discovered in 1958. In 2012, observations from the Van Allen Probes showed that a third belt can sometimes appear. The radiation is shown here in yellow, with green representing the spaces between the belts. Credit: NASA/Van Allen Probes/Goddard Space Flight Center To read more go to: www.nasa.gov/mission_pages/rbsp/news/third-belt.html NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

DensToolKit: A comprehensive open-source package for analyzing the electron density and its derivative scalar and vector fields

NASA Astrophysics Data System (ADS)

Solano-Altamirano, J. M.; Hernández-Pérez, Julio M.

2015-11-01

DensToolKit is a suite of cross-platform, optionally parallelized, programs for analyzing the molecular electron density (ρ) and several fields derived from it. Scalar and vector fields, such as the gradient of the electron density (∇ρ), electron localization function (ELF) and its gradient, localized orbital locator (LOL), region of slow electrons (RoSE), reduced density gradient, localized electrons detector (LED), information entropy, molecular electrostatic potential, kinetic energy densities K and G, among others, can be evaluated on zero, one, two, and three dimensional grids. The suite includes a program for searching critical points and bond paths of the electron density, under the framework of Quantum Theory of Atoms in Molecules. DensToolKit also evaluates the momentum space electron density on spatial grids, and the reduced density matrix of order one along lines joining two arbitrary atoms of a molecule. The source code is distributed under the GNU-GPLv3 license, and we release the code with the intent of establishing an open-source collaborative project. The style of DensToolKit's code follows some of the guidelines of an object-oriented program. This allows us to supply the user with a simple manner for easily implement new scalar or vector fields, provided they are derived from any of the fields already implemented in the code. In this paper, we present some of the most salient features of the programs contained in the suite, some examples of how to run them, and the mathematical definitions of the implemented fields along with hints of how we optimized their evaluation. We benchmarked our suite against both a freely-available program and a commercial package. Speed-ups of ˜2×, and up to 12× were obtained using a non-parallel compilation of DensToolKit for the evaluation of fields. DensToolKit takes similar times for finding critical points, compared to a commercial package. Finally, we present some perspectives for the future development and

Bernard van Leer Foundation Annual Review 1993 = Fundacion Bernard van Leer Revista Anual 1993.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This report, in both English and Spanish versions, aims to highlight the Bernard van Leer Foundation's identity, objectives, and major activities, as well as the work undertaken by the projects the foundation supports. The review features articles on the Foundation's work on advocacy, supporting families living in disadvantaged circumstances,…

Biochemical and genetic characterization of the vanC-2 vancomycin resistance gene cluster of Enterococcus casseliflavus ATCC 25788.

PubMed

Dutta, Ireena; Reynolds, Peter E

2002-10-01

The vanC-2 cluster of Enterococcus casseliflavus ATCC 25788 consisted of five genes (vanC-2, vanXY(C-2), vanT(C-2), vanR(C-2), and vanS(C-2)) and shared the same organization as the vanC cluster of E. gallinarum BM4174. The proteins encoded by these genes displayed a high degree of amino acid identity to the proteins encoded within the vanC gene cluster. The putative D,D-dipeptidase-D,D-carboxypeptidase, VanXY(C-2), exhibited 81% amino acid identity to VanXY(C), and VanT(C-2) displayed 65% amino acid identity to the serine racemase, VanT. VanR(C-2) and VanS(C-2) displayed high degrees of identity to VanR(C) and VanS(C), respectively, and contained the conserved residues identified as important to their function as a response regulator and histidine kinase, respectively. Resistance to vancomycin was expressed inducibly in E. casseliflavus ATCC 25788 and required an extended period of induction. Analysis of peptidoglycan precursors revealed that UDP-N-acetylmuramyl-L-Ala-delta-D-Glu-L-Lys-D-Ala-D-Ser could not be detected until several hours after the addition of vancomycin, and its appearance coincided with the resumption of growth. The introduction of additional copies of the vanT(C-2) gene, encoding a putative serine racemase, and the presence of supplementary D-serine in the growth medium both significantly reduced the period before growth resumed after addition of vancomycin. This suggested that the availability of D-serine plays an important role in the induction process.

Modes of thermal protection in polar bear cubs--at birth and on emergence from the den.

PubMed

Blix, A S; Lentfer, J W

1979-01-01

At birth in late December the polar bear is small (700 g), uninsulated, and helpless. It probably has a modest capacity for metabolic heat production and depends on the female and a snow den in which it is born for thermal protection. The microclimate of an artificial polar bear den was investigated at Point Barrow, AK, and the temperature therein found to stay around 0 degrees C provided a heat source (200 W) equivalent to an adult polar bear was introduced. When the bears desert the den in early April the cub has grown to about 10 kg and has a well-developed fur insulation, but almost no subcutaneous fat. The cub has a high resting metabolic rate (4.6 W.kg-1), which is supported by the fat polar bear milk. Its lower critical temperature is about -30 degrees C, and an ambient temperature of -45 degrees C results in only a 33% increase in metabolism. The cub can tolerate a wind chill of 2.3 kW.m2 without apparent stress of drop in rectal temperature. If the cub is immersed in ice water rectal temperature drops 11 degrees C in 30 min. It is concluded that the cub can tolerate extremely low temperatures in air due to fur insulation and high metabolic heat production, but is unable to cope with the chill of ice water for any prolonged period of time.

Velocity Measurements on the Electric Gun Developed at the TNO Prins Maurits Laboratory (Snelheidheidsmetingen aan de bij het Prins Maurits Laboratorium Ontwikkelde Electric Gun)

DTIC Science & Technology

1993-03-01

8 2.3 De Flyer Plate Assembly (.FPA) 9 3 OPZET VAN DE MFTThIGEN 11 3.1 De djfferentjaalstroommetiflg 11 3.2 Stroommetingen 12 3.3...25 n11)" II )60 S. L) I.P014 25 ,rzit II ,0 8 9 28 ).7 I 10.7 273.0 2.15 43790 1.318 - - - IM,𔃺I5 25 Nr. 11 60 8.9 279.t) 125.9 274.1 2.22 44406 1...4 HWO-KLU 5 HWO-KM 6 DMKL J.A. van Gool 7/ 9 TDCK 10 Hoofddirecteur DO-TNO 11 Lid Inst jtuuts Advies Raad PMIL Prof. drs. P.J. van den Berg 12 Lid

DenInv3D: a geophysical software for three-dimensional density inversion of gravity field data

NASA Astrophysics Data System (ADS)

Tian, Yu; Ke, Xiaoping; Wang, Yong

2018-04-01

This paper presents a three-dimensional density inversion software called DenInv3D that operates on gravity and gravity gradient data. The software performs inversion modelling, kernel function calculation, and inversion calculations using the improved preconditioned conjugate gradient (PCG) algorithm. In the PCG algorithm, due to the uncertainty of empirical parameters, such as the Lagrange multiplier, we use the inflection point of the L-curve as the regularisation parameter. The software can construct unequally spaced grids and perform inversions using such grids, which enables changing the resolution of the inversion results at different depths. Through inversion of airborne gradiometry data on the Australian Kauring test site, we discovered that anomalous blocks of different sizes are present within the study area in addition to the central anomalies. The software of DenInv3D can be downloaded from http://159.226.162.30.

The Study of Nationalism. A Bibliographic Essay on the Literature Published in the English Language,

DTIC Science & Technology

1975-01-01

accommodating sovereignty and the regional integration of Europe. (9) Jeremy Haritos, Nationalism and European Inteeration A Study of - 56 - French... Bentham van den Bergh, "Contemporary Nationalism in the Western World" in Stanley Hoffman (pd.), Conditions of World Order (New York: Simon and

Instructional Aspects of Intelligent Tutoring Systems.

ERIC Educational Resources Information Center

Pieters, Jules M., Ed.

This collection contains three papers addressing the instructional aspects of intelligent tutoring systems (ITS): (1) "Some Experiences with Two Intelligent Tutoring Systems for Teaching Computer Programming: Proust and the LISP-Tutor" (van den Berg, Merrienboer, and Maaswinkel); (2) "Some Issues on the Construction of Cooperative…

The Effects of Differing Oxygen Concentrations on Reaction Time Performance at Altitude

DTIC Science & Technology

2014-12-04

49, 943-946. Harding, R. M., Mills, F. J. (1983). Problems of altitude: Hypoxia and hyperventilation . British Medical Journal, 286, 1408-1410...K. P., Schippers, N., & Van den Bergh, O. (2000). Hyperventilation and attention: effects of hypocapnia on performance in a Stroop task. Biological

Learning Objects: A User-Centered Design Process

ERIC Educational Resources Information Center

Branon, Rovy F., III

2011-01-01

Design research systematically creates or improves processes, products, and programs through an iterative progression connecting practice and theory (Reinking, 2008; van den Akker, 2006). Developing a new instructional systems design (ISD) processes through design research is necessary when new technologies emerge that challenge existing practices…

Van Kampen Colimits as Bicolimits in Span

NASA Astrophysics Data System (ADS)

Heindel, Tobias; Sobociński, Paweł

The exactness properties of coproducts in extensive categories and pushouts along monos in adhesive categories have found various applications in theoretical computer science, e.g. in program semantics, data type theory and rewriting. We show that these properties can be understood as a single universal property in the associated bicategory of spans. To this end, we first provide a general notion of Van Kampen cocone that specialises to the above colimits. The main result states that Van Kampen cocones can be characterised as exactly those diagrams in ℂ that induce bicolimit diagrams in the bicategory of spans mathcal{S}pan_{mathbb{C}}, provided that ℂ has pullbacks and enough colimits.

Conservative Management of Dens Evaginatus: Report of Two Unusual Cases

PubMed Central

Vijaykumar, S; Tenny, J; Ravi, GR

2010-01-01

ABSTRACT Dens evaginatus (DE) is a rare developmental anomaly characterized by presence of an extra cusp arising from occlusal or lingual surfaces. Isolated occurrence or concomitant presence of DE with other dental anomalies has been reported. DE commonly affects permanent teeth and is rarely seen in primary dentition. Treatment may be conservative or radical. This article presents two unusual cases of concomitant occurrence of a supernumerary tooth and DE affecting maxillary deciduous lateral incisor and conservative management of DE occurring concurrently with a possible Oehler’s type I invagination in maxillary permanent lateral incisor. PMID:27507925

Steppe lion remains imported by Ice Age spotted hyenas into the Late Pleistocene Perick Caves hyena den in northern Germany

NASA Astrophysics Data System (ADS)

Diedrich, Cajus G.

2009-05-01

Upper Pleistocene remains of the Ice Age steppe lion Panthera leo spelaea (Goldfuss, 1810) have been found in the Perick Caves, Sauerland Karst, NW Germany. Bones from many hyenas and their imported prey dating from the Lower to Middle Weichselian have also been recovered from the Perick Cave hyena den. These are commonly cracked or exhibit deep chew marks. The absence of lion cub bones, in contrast to hyena and cave bear cub remains in the Perick Caves, and other caves of northern Germany, excludes the possibility that P. leo spelaea used the cave for raising cubs. Only in the Wilhelms Cave was a single skeleton of a cub found in a hyena den. Evidence of the chewing, nibbling and cracking of lion bones and crania must have resulted from the importation and destruction of lion carcasses (4% of the prey fauna). Similar evidence was preserved at other hyena den caves and open air sites in Germany. The bone material from the Perick and other Central European caves points to antagonistic hyena and lion conflicts, similar to clashes of their modern African relatives.

Flower Still Life, Maria Van Oosterwijck

ERIC Educational Resources Information Center

Holtrop, Emily

2004-01-01

This brief article describes the life of Maria van Oosterwijck. It also discusses her art and its significance and symbolism. A list of suggested activities for elementary, middle, and high school students is included.

Experimental Testing of a Van De Graaff Generator as an Electromagnetic Pulse Generator

DTIC Science & Technology

2016-07-01

EXPERIMENTAL TESTING OF A VAN DE GRAAFF GENERATOR AS AN ELECTROMAGNETIC PULSE GENERATOR THESIS...protection in the United States AFIT-ENP-MS-16-S-075 EXPERIMENTAL TESTING OF A VAN DE GRAAFF GENERATOR AS AN ELECTROMAGNETIC PULSE GENERATOR...RELEASE; DISTRIBUTION UNLIMITED. AFIT-ENP-MS-16-S-075 EXPERIMENTAL TESTING OF A VAN DE GRAAFF GENERATOR AS AN ELECTROMAGNETIC PULSE GENERATOR

Aldo van Eyck’s Playgrounds: Aesthetics, Affordances, and Creativity

PubMed Central

Withagen, Rob; Caljouw, Simone R.

2017-01-01

After World War II, the Dutch architect Aldo van Eyck developed hundreds of playgrounds in the city of Amsterdam. These public playgrounds were located in parks, squares, and derelict sites, and consisted of minimalistic aesthetic play equipment that was supposed to stimulate the creativity of children. Over the last decades, these playgrounds have been studied by sociologists, theorists of art and architecture, and psychologists. Adopting an ecological approach to the human environment, it is argued that the abstract forms of van Eyck’s play sculptures indeed stimulate the creativity of the child. Whereas a slide or a swing almost dictates what a child is supposed to do, van Eyck’s play equipment invites the child to actively explore the numerous affordances (action possibilities) it provided. However, it is argued that the standardization (e.g., equal distances between blocks or bars) that tends to characterize van Eyck’ play equipment has negative effects on the playability. This standardization, which was arguably the result of the aesthetic motives of the designer, might be appealing to children when simply looking at the equipment, but it is not of overriding importance to them when playing in it. Indeed, a recent study indicates that the affordances provided by messy structures appear to have a greater appeal to playing children. PMID:28725208

d-Ala-d-Ser VanN-Type Transferable Vancomycin Resistance in Enterococcus faecium▿

PubMed Central

Lebreton, François; Depardieu, Florence; Bourdon, Nancy; Fines-Guyon, Marguerite; Berger, Pierre; Camiade, Sabine; Leclercq, Roland; Courvalin, Patrice; Cattoir, Vincent

2011-01-01

Enterococcus faecium UCN71, isolated from a blood culture, was resistant to low levels of vancomycin (MIC, 16 μg/ml) but susceptible to teicoplanin (MIC, 0.5 μg/ml). No amplification was observed with primers specific for the previously described glycopeptide resistance ligase genes, but a PCR product corresponding to a gene called vanN was obtained using degenerate primers and was sequenced. The deduced VanN protein was related (65% identity) to the d-alanine:d-serine VanL ligase. The organization of the vanN gene cluster, determined using degenerate primers and by thermal asymmetric interlaced (TAIL)-PCR, was similar to that of the vanC operons. A single promoter upstream from the resistance operon was identified by rapid amplification of cDNA ends (RACE)-PCR. The presence of peptidoglycan precursors ending in d-serine and d,d-peptidase activities in the absence of vancomycin indicated constitutive expression of the resistance operon. VanN-type resistance was transferable by conjugation to E. faecium. This is the first report of transferable d-Ala-d-Ser-type resistance in E. faecium. PMID:21807981

Quantum synchronization of quantum van der Pol oscillators with trapped ions.

PubMed

Lee, Tony E; Sadeghpour, H R

2013-12-06

The van der Pol oscillator is the prototypical self-sustained oscillator and has been used to model nonlinear behavior in biological and other classical processes. We investigate how quantum fluctuations affect phase locking of one or many van der Pol oscillators. We find that phase locking is much more robust in the quantum model than in the equivalent classical model. Trapped-ion experiments are ideally suited to simulate van der Pol oscillators in the quantum regime via sideband heating and cooling of motional modes. We provide realistic experimental parameters for 171Yb+ achievable with current technology.

Colossal terahertz nonlinearity of tunneling van der Waals gap (Conference Presentation)

NASA Astrophysics Data System (ADS)

Bahk, Young-Mi; Kang, Bong Joo; Kim, Yong Seung; Kim, Joon-Yeon; Kim, Won Tae; Kim, Tae Yun; Kang, Taehee; Rhie, Ji Yeah; Han, Sanghoon; Park, Cheol-Hwan; Rotermund, Fabian; Kim, Dai-Sik

2016-09-01

We manufactured an array of three angstrom-wide, five millimeter-long van der Waals gaps of copper-graphene-copper composite, in which unprecedented nonlinearity was observed. To probe and manipulate van der Waals gaps with long wavelength electromagnetic waves such as terahertz waves, one is required to fabricate vertically oriented van der Waals gaps sandwiched between two metal planes with an infinite length in the sense of being much larger than any of the wavelengths used. By comparison with the simple vertical stacking of metal-graphene-metal structure, in our structure, background signals are completely blocked enabling all the light to squeeze through the gap without any strays. When the angstrom-sized van der Waals gaps are irradiated with intense terahertz pulses, the transient voltage across the gap reaches up to 5 V with saturation, sufficiently strong to deform the quantum barrier of angstrom gaps. The large transient potential difference across the gap facilitates electron tunneling through the quantum barrier, blocking terahertz waves completely. This negative feedback of electron tunneling leads to colossal nonlinear optical response, a 97% decrease in the normalized transmittance. Our technology for infinitely long van der Waals gaps can be utilized for other atomically thin materials than single layer graphene, enabling linear and nonlinear angstrom optics in a broad spectral range.

Protective Effect of Ethanolic Extract of Tabernaemontana divaricata (L.) R. Br. against DEN and Fe NTA Induced Liver Necrosis in Wistar Albino Rats

PubMed Central

2014-01-01

This study is an attempt to evaluate the hepatoprotective activity of Tabernaemontana divaricata against DEN and Fe NTA induced liver necrosis in rats. Ethanolic extract of the whole plant of Tabernaemontana divaricata at doses of 200 and 400 mg/kg body weight and 5-fluorouracil (standard drug) was orally administered to male Wistar Albino rats once daily for 24 weeks, simultaneously treated with the carcinogen DEN and Fe NTA. In simultaneously treated animals, the plant extract significantly decreased the levels of uric acid, bilirubin, AST, ALT, and ALP in serum and increased the levels of liver marker enzymes in liver. Treatment with the extracts resulted in a significant increase in the levels of antioxidants accompanied by a marked reduction in the levels of malondialdehyde when compared to DEN and Fe NTA treated group. When compared with 200 mg/kg bw rats, 400 mg/kg bw rats and 5-fluorouracil treated rats showed better results in all the parameters. The histopathological studies confirmed the protective effects of extract against DEN and Fe NTA induced liver necrosis. Thus, it could be concluded that the use of Tabernaemontana divaricata extract in the treatment of carcinogen induced hepatic necrosis. PMID:25136566

Joint DEnKF-albedo assimilation scheme that considers the common land model subgrid heterogeneity and a snow density-based observation operator for improving snow depth simulations

NASA Astrophysics Data System (ADS)

Xu, Jianhui; Zhang, Feifei; Zhao, Yi; Shu, Hong; Zhong, Kaiwen

2016-07-01

For the large-area snow depth (SD) data sets with high spatial resolution in the Altay region of Northern Xinjiang, China, we present a deterministic ensemble Kalman filter (DEnKF)-albedo assimilation scheme that considers the common land model (CoLM) subgrid heterogeneity. In the albedo assimilation of DEnKF-albedo, the assimilated albedos over each subgrid tile are estimated with the MCD43C1 bidirectional reflectance distribution function (BRDF) parameters product and CoLM calculated solar zenith angle. The BRDF parameters are hypothesized to be consistent over all subgrid tiles within a specified grid. In the SCF assimilation of DEnKF-albedo, a DEnKF combining a snow density-based observation operator considers the effects of the CoLM subgrid heterogeneity and is employed to assimilate MODIS SCF to update SD states over all subgrid tiles. The MODIS SCF over a grid is compared with the area-weighted sum of model predicted SCF over all the subgrid tiles within the grid. The results are validated with in situ SD measurements and AMSR-E product. Compared with the simulations, the DEnKF-albedo scheme can reduce errors of SD simulations and accurately simulate the seasonal variability of SD. Furthermore, it can improve simulations of SD spatiotemporal distribution in the Altay region, which is more accurate and shows more detail than the AMSR-E product.

Application of Diffusion Monte Carlo to Materials Dominated by van der Waals Interactions

DOE PAGES

Benali, Anouar; Shulenburger, Luke; Romero, Nichols A.; ...

2014-06-12

Van der Waals forces are notoriously difficult to account for from first principles. We perform extensive calculation to assess the usefulness and validity of diffusion quantum Monte Carlo when applied to van der Waals forces. We present results for noble gas solids and clusters - archetypical van der Waals dominated assemblies, as well as a relevant pi-pi stacking supramolecular complex: DNA + intercalating anti-cancer drug Ellipticine.

Heterologous expression of glycopeptide resistance vanHAX gene clusters from soil bacteria in Enterococcus faecalis.

PubMed

Hasman, Henrik; Aarestrup, Frank M; Dalsgaard, Anders; Guardabassi, Luca

2006-04-01

The aim of the study was to determine whether glycopeptide resistance gene clusters from soil bacteria could be heterologously expressed in Enterococcus faecalis and adapt to the new host following exposure to vancomycin. The vanHAX clusters from Paenibacillus thiaminolyticus PT-2B1, Paenibacillus apiarius PA-B2B and Amycolatopsis coloradensis DSM 44225 were separately cloned in an appropriately constructed shuttle vector containing the two-component regulatory system (vanRS) of Tn1546. The complete vanA(PT) operon (vanRSHAXY) from P. thiaminolyticus PT-2B1 was cloned in the same shuttle vector lacking enterococcal vanRS. All plasmid constructs were electroporated into E. faecalis JH2-2 and the MICs of vancomycin and teicoplanin were determined for each recombinant strain before and following exposure to sublethal concentrations of vancomycin. The vanHAX clusters from P. thiaminolyticus and P. apiarius conferred high-level vancomycin resistance (MIC > or = 125 mg/L) in E. faecalis JH2-2. In contrast, cloning of the vanHAX cluster from A. coloradensis did not result in a significant increase of vancomycin resistance (MIC = 0.7 mg/L). Resistance to vancomycin was not observed after cloning the complete vanA(PT) operon from P. thiaminolyticus (MIC = 2 mg/L), but this recombinant rapidly adapted to high concentrations of vancomycin (MIC = 500 mg/L) following exposure to sub-lethal concentrations of this antibiotic. The results showed that vanA(PT) in P. thiaminolyticus is a possible ancestor of vanA-mediated glycopeptide resistance in enterococci. Experimental evidence supported the hypothesis that enterococci did not acquire glycopeptide resistance directly from glycopeptide-producing organisms such as A. coloradensis.

Cosmological models constructed by van der Waals fluid approximation and volumetric expansion

NASA Astrophysics Data System (ADS)

Samanta, G. C.; Myrzakulov, R.

The universe modeled with van der Waals fluid approximation, where the van der Waals fluid equation of state contains a single parameter ωv. Analytical solutions to the Einstein’s field equations are obtained by assuming the mean scale factor of the metric follows volumetric exponential and power-law expansions. The model describes a rapid expansion where the acceleration grows in an exponential way and the van der Waals fluid behaves like an inflation for an initial epoch of the universe. Also, the model describes that when time goes away the acceleration is positive, but it decreases to zero and the van der Waals fluid approximation behaves like a present accelerated phase of the universe. Finally, it is observed that the model contains a type-III future singularity for volumetric power-law expansion.

Crater Wall in Van de Graaff

NASA Image and Video Library

2010-02-11

This image taken NASA Lunar Reconnaissance Orbiter shows the wall of crater Van de Graaff C, where brighter material is exposed by more active processes associated with steeper slopes, recent small craters, and even individual rolling boulders.

Polyclonal emergence of vanA vancomycin-resistant Enterococcus faecium in Australia.

PubMed

van Hal, Sebastiaan J; Espedido, Björn A; Coombs, Geoffrey W; Howden, Benjamin P; Korman, Tony M; Nimmo, Graeme R; Gosbell, Iain B; Jensen, Slade O

2017-04-01

To investigate the genetic context associated with the emergence of vanA VRE in Australia. The whole genomes of 18 randomly selected vanA -positive Enterococcus faecium patient isolates, collected between 2011 and 2013 from hospitals in four Australian capitals, were sequenced and analysed. In silico typing and transposon/plasmid assembly revealed that the sequenced isolates represented (in most cases) different hospital-adapted STs and were associated with a variety of different Tn 1546 variants and plasmid backbone structures. The recent emergence of vanA VRE in Australia was polyclonal and not associated with the dissemination of a single 'dominant' ST or vanA -encoding plasmid. Interestingly, the factors contributing to this epidemiological change are not known and future studies may need to consider investigation of potential community sources. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Benelux Colloquium on Geomorphological Processes and Soils (4th) Held in Amsterdam and Leuven on April 24-May 2, 1988. Excursion Guide

DTIC Science & Technology

1988-01-01

Utrecht and Lidge. The colloquium is being organised by the Laboratoy of Experimental Geomorphology, Catholic University of Leuven and the Laboratory of...37 ARTIKELEN EN RAPPORM!N Ancker, J.A.24.van den & Jungeriuc, P.D., 1985. Recante duinvormingupro- cessen langs de Franse vastkust. Intern Rapport

Rectification of thermal fluctuations in ideal gases.

PubMed

Meurs, P; Van den Broeck, C; Garcia, A

2004-11-01

We calculate the systematic average speed of the adiabatic piston and a thermal Brownian motor, introduced by C. Van den Broeck, R, Kawai and P. Meurs [Phys. Rev. Lett. 93, 090601 (2004)], by an expansion of the Boltzmann equation and compare with the exact numerical solution.

Storings analyse Ten Behoeve van het Materieelverzorgingsplan (Failure Analysis for the Maintenance Plan)

DTIC Science & Technology

1990-05-01

oporachtnemer verwezen naar de ’Algemone Voorwaarden voor Onderzoeks- opdrachten TNO’. dan wet de betreflende terzake fijasen partlijen gesloten * 11 ...ixvulling van het onderhoudsschema 9 2.4 Invulling van het onderhoudsschema in de praktijk 14 2.5 Gonclusies 16 3 STORINGSANALYSES 18 3.1 ’Failure mode...nnfd- en subgroep (dit is een opdeling van bet systeem naar functioneel sanienhangende delen). Pa gina 9 - Het onderhoudsniveau waar jedere

Theory of coherent van der Waals matter.

PubMed

Kulić, Igor M; Kulić, Miodrag L

2014-12-01

We explain in depth the previously proposed theory of the coherent van der Waals (cvdW) interaction, the counterpart of van der Waals (vdW) force, emerging in spatially coherently fluctuating electromagnetic fields. We show that cvdW driven matter is dominated by many-body interactions, which are significantly stronger than those found in standard van der Waals (vdW) systems. Remarkably, the leading two- and three-body interactions are of the same order with respect to the distance (∝R(-6)), in contrast to the usually weak vdW three-body effects (∝R(-9)). From a microscopic theory we show that the anisotropic cvdW many-body interactions drive the formation of low-dimensional structures such as chains, membranes, and vesicles with very unusual, nonlocal properties. In particular, cvdW chains display a logarithmically growing stiffness with the chain length, while cvdW membranes have a bending modulus growing linearly with their size. We argue that the cvdW anisotropic many-body forces cause local cohesion but also a negative effective "surface tension." We conclude by deriving the equation of state for cvdW materials and propose experiments to test the theory, in particular the unusual three-body nature of cvdW.

Theory of coherent van der Waals matter

NASA Astrophysics Data System (ADS)

Kulić, Igor M.; Kulić, Miodrag L.

2014-12-01

We explain in depth the previously proposed theory of the coherent van der Waals (cvdW) interaction, the counterpart of van der Waals (vdW) force, emerging in spatially coherently fluctuating electromagnetic fields. We show that cvdW driven matter is dominated by many-body interactions, which are significantly stronger than those found in standard van der Waals (vdW) systems. Remarkably, the leading two- and three-body interactions are of the same order with respect to the distance (∝R-6) , in contrast to the usually weak vdW three-body effects (∝R-9 ). From a microscopic theory we show that the anisotropic cvdW many-body interactions drive the formation of low-dimensional structures such as chains, membranes, and vesicles with very unusual, nonlocal properties. In particular, cvdW chains display a logarithmically growing stiffness with the chain length, while cvdW membranes have a bending modulus growing linearly with their size. We argue that the cvdW anisotropic many-body forces cause local cohesion but also a negative effective "surface tension." We conclude by deriving the equation of state for cvdW materials and propose experiments to test the theory, in particular the unusual three-body nature of cvdW.

van Maanen, Adriaan (1884-1947)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Dutch astronomer, became a member of the Mount Wilson staff, and studied the rotation of spiral nebulae as a means to establish their distances. His detection of rotational motions was illusory and misleadingly suggested that they were relatively nearby. Through its proper motion and parallax, he discovered the white dwarf van Maanen's star....

A revision of the tribe Planitorini van Achterberg (Hymenoptera, Braconidae, Euphorinae), with description of a new genus from Australia.

PubMed

van Achterberg, Cornelis; Quicke, Donald L J; Boring, C Andrew

2017-01-01

The tribe Planitorini van Achterberg (Hymenoptera: Braconidae: Euphorinae) is revised. One new genus Paramannokeraia gen. n. (type species: P. gibsoni sp. n. ) and five new species from Australia are described and illustrated: Mannokeraia albipalpis van Achterberg, sp. n. , M. nigrita van Achterberg, sp. n. , M. punctata van Achterberg, sp. n. , Paramannokeraia gibsoni van Achterberg & Quicke, sp. n. and P. juliae van Achterberg, sp. n. The tribe Mannokeraiini van Achterberg, 1995, is synonymized with the tribe Planitorini ( syn. n. ).

Science, Sex, and Pictures: Reflections on Van Fraassen's Use of Perspectival Representations

NASA Astrophysics Data System (ADS)

Okruhlik, Kathleen

2014-03-01

Bas van Fraassen's brand of empiricism, as articulated in his well-known constructive empiricism and his more recent empiricist structuralism, has been developed using the so-called semantic approach to scientific theories. This approach has allowed van Fraassen to espouse quite a robust form of non-realism about unobservable entities while avoiding some of the problems that contributed to the demise of logical empiricism. I shall argue, however, that in other respects van Fraassen replicates many of the serious shortcomings associated with the earlier tradition -- despite the fact that his choice of language sometimes obscures those similarities. Because van Fraassen's empiricist structuralism is much less well-known than his constructive empiricism, the rather lengthy first section of this paper provides an overview and initial assessment of that position. Subsequent sections deal with the ways in which van Fraassen's very sophisticated form of empiricism not only fails to address some of the most serious shortcomings of logical empiricism but actually reinforces them. The chief focus is on the failure to address issues that arise from the historical and social contexts within which science is pursued -- this despite a vocabulary rich in references to perspectivity, pragmatics, context, use, and aims.

A revision of the tribe Planitorini van Achterberg (Hymenoptera, Braconidae, Euphorinae), with description of a new genus from Australia

PubMed Central

van Achterberg, Cornelis; Quicke, Donald L.J.; Boring, C. Andrew

2017-01-01

Abstract The tribe Planitorini van Achterberg (Hymenoptera: Braconidae: Euphorinae) is revised. One new genus Paramannokeraia gen. n. (type species: P. gibsoni sp. n.) and five new species from Australia are described and illustrated: Mannokeraia albipalpis van Achterberg, sp. n., M. nigrita van Achterberg, sp. n., M. punctata van Achterberg, sp. n., Paramannokeraia gibsoni van Achterberg & Quicke, sp. n. and P. juliae van Achterberg, sp. n. The tribe Mannokeraiini van Achterberg, 1995, is synonymized with the tribe Planitorini (syn. n.). PMID:29290713

Conspecific scent trailing by garter snakes (Thamnophis sirtalis) during autumn Further evidence for use of pheromones in den location.

PubMed

Costanzo, J P

1989-11-01

Adult garter snakes (Thamnophis sirtalis), collected in October near a traditional, communal hibernaculum in central Wisconsin, were acclimated to autumnal conditions and subjected to laboratory tests to determine whether they could follow scent trails of a conspecific. Graded responses were obtained, but 75% of the sample showed at least some inclination to follow scent trails. The results suggest that pheromone cues may be used by male and female garter snakes to locate traditional dens during autumnal migrations. Evidence from this and other studies suggests that pheromones are probably used in conjunction with other homing mechanisms and that the role of pheromones in den location may be more important in younger snakes and in populations inhabiting northern latitudes.

[Johann van Beethoven (1776-1848)].

PubMed

Eikermann, Erika

2012-01-01

The article about the life and achievements of the apothecary Johann van Beethoven, the younger brother of the composer Ludwig van Beethoven, depicts a vivid picture of life in the 18th, 19t century. Research on archived original documents in Bonn, Vienna and Linz on the Danube made it possible to reveal details about the relationship inside this famous family and describes the hurdles of life of a successful apothecary. In 1776 Johann van Beethoven was born as the fourth child of the Beethoven family, a family of Bonner musicians. In 1790 he began his apprenticeship to become an apothecary at the Bonner "Hofapotheke". Towards the end of 1795 he moved to join his older brothers Ludwig and Karl in Vienna. During his time there he worked as a "subject" in various Viennese pharmacies. However in 1808 he purchased the pharmacy "Zur Goldenen Krone" in Linz on the Danube. His new pharmacy flourished, supplying first the Napoleonic occupation troops, and later the Austrian Military with medicines and field dressing/bandage materials. When in 1812 he married his Housekeeper, his Brother Ludwig opposed harshly, on reasons of social status and on moral grounds. Four years later, in 1816 Johann sold the pharmacy in Linz and founded a new pharmacy in Urfahr, on the opposite bank of the Danube. In 1819 he became a squire (or landowner), when he purchased a manor estate in Gneixendorf, near Krems on the Danube. In spite of his numerous duties as an apothecary and squire, Johann was frequently resident in Vienna, supporting his brother both emotionally and pharmaceutically. At the end of his life Johann sold both his pharmacy and the Gneixendorf estate, and spent his last years as a private gentleman living a dazzling lifestyle in Vienna. He died on January 12th 1848 and was buried in Vienna's "Waldmüllerpark".

Brown-Vialetto-Van Laere syndrome.

PubMed

Francis, D A; Ponsford, J R; Wiles, C M; Thomas, P K; Duchen, L W

1993-02-01

The clinical and pathological findings of a male with the Brown-Vialetto-Van Laere syndrome are described. This rare and fatal affection of the nervous system involves mainly the brain stem with the prominent and early manifestation of sensorineural deafness. Increased awareness and documentation of this disorder has added information on the mode of inheritance.

Van vleck paramagnetism in orthorhombic TiO2 (Brookite)

USGS Publications Warehouse

Senftle, F.E.; Thorpe, A.N.

1968-01-01

The magnetic susceptibility of the orthorhombic form of titanium dioxide has been measured from 5 to 300??K. After deducting the temperature-dependent component, which is probably due to defects or impurities, and the free-ion diamagnetic component, the Van Vleck paramagnetism was estimated to be 33??10-6 emu/mole. Comparison is made between this value and the Van Vleck paramagnetism of strontium titanate and the two tetragonal forms of titanium dioxide: rutile and anatase. ?? 1968 The American Physical Society.

Implication of Two-Coupled Differential Van der Pol Duffing Oscillator in Weak Signal Detection

NASA Astrophysics Data System (ADS)

Peng, Hang-hang; Xu, Xue-mei; Yang, Bing-chu; Yin, Lin-zi

2016-04-01

The principle of the Van der Pol Duffing oscillator for state transition and for determining critical value is described, which has been studied to indicate that the application of the Van der Pol Duffing oscillator in weak signal detection is feasible. On the basis of this principle, an improved two-coupled differential Van der Pol Duffing oscillator is proposed which can identify signals under any frequency and ameliorate signal-to-noise ratio (SNR). The analytical methods of the proposed model and the construction of the proposed oscillator are introduced in detail. Numerical experiments on the properties of the proposed oscillator compared with those of the Van der Pol Duffing oscillator are carried out. Our numerical simulations have confirmed the analytical treatment. The results demonstrate that this novel oscillator has better detection performance than the Van der Pol Duffing oscillator.

Bacoside A downregulates matrix metalloproteinases 2 and 9 in DEN-induced hepatocellular carcinoma.

PubMed

Janani, Panneerselvam; Sivakumari, Kanakarajan; Geetha, Arumugam; Yuvaraj, Sambandam; Parthasarathy, Chandrakesan

2010-03-01

Cancer metastasis is a complex multi-step process, responsible for a majority of cancer-related deaths by affecting the critical organs and causing complications in therapies. Hepatocellular carcinoma is a multi-factorial disease and is the third most common cause of cancer related mortality worldwide. Clinical and experimental studies have shown that MMP-2 and MMP-9 are involved in tumor invasion and metastases and their elevated expression has been associated with poor prognosis. Our recent studies showed a strong anti-oxidant and hepatoprotective effects of bacoside A (BA) against carcinogen. Nevertheless the effect of BA on the activities and expression of MMP-2 and MMP-9 during hepatocellular carcinoma is not yet recognized. Therefore, the present study was designed to assess the same. Results of gelatin zymography study showed that BA co-treatment significantly decreased the activities of MMP-2 and MMP-9, which is increased during hepatocellular carcinoma. Further immunoblot analysis showed decreased expression of MMP-2 and MMP-9 in rats co-treated with BA compared to DEN-induced hepatocellular carcinoma. Our results reveal that BA exerts its anti-metastatic effect against DEN-induced hepatocellular carcinoma by inhibiting the activities and expressions of MMP-2 and MMP-9. 2010 John Wiley & Sons, Ltd.

How Authors and Readers of ePortfolios Make Collaborative Meaning

ERIC Educational Resources Information Center

Benander, Ruth; Refaei, Brenda

2016-01-01

This article reports on a case study, using a think-aloud approach (Boren & Ramey, 2000; Jaspers, Steen, van den Bos & Geenen, 2004; Kilsdonk et al., 2016), to investigate how different types of audiences interpret ePortfolios. During recorded viewing, students, instructors, and business professionals narrated their experience of reading…

Using Avatars and Virtual Environments in Learning: What Do They Have to Offer?

ERIC Educational Resources Information Center

Falloon, Garry

2010-01-01

This paper explores and discusses arguments for the use of virtual environments and interactive avatars in supporting the achievement of student learning goals within conventional educational contexts. It describes and evaluates arguments promoted by some authors (eg, van den Brekel, 2007; Deuchar & Nodder, 2003; Dickey, 2003; Facer, 2004; de…

Observation of van Hove Singularities in Twisted Silicene Multilayers

PubMed Central

2016-01-01

Interlayer interactions perturb the electronic structure of two-dimensional materials and lead to new physical phenomena, such as van Hove singularities and Hofstadter’s butterfly pattern. Silicene, the recently discovered two-dimensional form of silicon, is quite unique, in that silicon atoms adopt competing sp2 and sp3 hybridization states leading to a low-buckled structure promising relatively strong interlayer interaction. In multilayer silicene, the stacking order provides an important yet rarely explored degree of freedom for tuning its electronic structures through manipulating interlayer coupling. Here, we report the emergence of van Hove singularities in the multilayer silicene created by an interlayer rotation. We demonstrate that even a large-angle rotation (>20°) between stacked silicene layers can generate a Moiré pattern and van Hove singularities due to the strong interlayer coupling in multilayer silicene. Our study suggests an intriguing method for expanding the tunability of the electronic structure for electronic applications in this two-dimensional material. PMID:27610412

Observation of van Hove Singularities in Twisted Silicene Multilayers.

PubMed

Li, Zhi; Zhuang, Jincheng; Chen, Lan; Ni, Zhenyi; Liu, Chen; Wang, Li; Xu, Xun; Wang, Jiaou; Pi, Xiaodong; Wang, Xiaolin; Du, Yi; Wu, Kehui; Dou, Shi Xue

2016-08-24

Interlayer interactions perturb the electronic structure of two-dimensional materials and lead to new physical phenomena, such as van Hove singularities and Hofstadter's butterfly pattern. Silicene, the recently discovered two-dimensional form of silicon, is quite unique, in that silicon atoms adopt competing sp(2) and sp(3) hybridization states leading to a low-buckled structure promising relatively strong interlayer interaction. In multilayer silicene, the stacking order provides an important yet rarely explored degree of freedom for tuning its electronic structures through manipulating interlayer coupling. Here, we report the emergence of van Hove singularities in the multilayer silicene created by an interlayer rotation. We demonstrate that even a large-angle rotation (>20°) between stacked silicene layers can generate a Moiré pattern and van Hove singularities due to the strong interlayer coupling in multilayer silicene. Our study suggests an intriguing method for expanding the tunability of the electronic structure for electronic applications in this two-dimensional material.

J. H. Van Vleck and Magnetism at the University of Wisconsin: 1928 -1934

NASA Astrophysics Data System (ADS)

Huber, David

2011-03-01

In 1928, John Van Vleck returned to his alma mater to take a position in the Physics Department. Six years later he left to join the faculty of Harvard University. While Van Vleck was at Wisconsin, he began a series of theoretical studies that helped lay the foundation for the modern theory of magnetism in solids. In 1932 Van Vleck published his celebrated monograph, The Theory of Electric and Magnetic Susceptibilities, in which he made use of the new theory to explain the results of experimental studies in a variety of magnetic materials. In my talk, I will review the accomplishments of Van Vleck and his students during this period and also comment briefly on his notes for a second edition of the book.

Electromagnetic van Kampen waves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ignatov, A. M., E-mail: aign@fpl.gpi.ru

2017-01-15

The theory of van Kampen waves in plasma with an arbitrary anisotropic distribution function is developed. The obtained solutions are explicitly expressed in terms of the permittivity tensor. There are three types of perturbations, one of which is characterized by the frequency dependence on the wave vector, while for the other two, the dispersion relation is lacking. Solutions to the conjugate equations allowing one to solve the initial value problem are analyzed.

Spacecraft-level verification of the Van Allen Probes' RF communication system

NASA Astrophysics Data System (ADS)

Crowne, M. J.; Srinivasan, D.; Royster, D.; Weaver, G.; Matlin, D.; Mosavi, N.

This paper presents the verification process, lessons learned, and selected test results of the radio frequency (RF) communication system of the Van Allen Probes, formerly known as the Radiation Belt Storm Probes (RBSP). The Van Allen Probes mission is investigating the doughnut-shaped regions of space known as the Van Allen radiation belts where the Sun interacts with charged particles trapped in Earth's magnetic field. Understanding this dynamic area that surrounds our planet is important to improving our ability to design spacecraft and missions for reliability and astronaut safety. The Van Allen Probes mission features two nearly identical spacecraft designed, built, and operated by the Johns Hopkins University Applied Physics Laboratory (JHU/APL) for the National Aeronautics and Space Administration (NASA). The RF communication system features the JHU/APL Frontier Radio. The Frontier Radio is a software-defined radio (SDR) designed for spaceborne communications, navigation, radio science, and sensor applications. This mission marks the first spaceflight usage of the Frontier Radio. RF ground support equipment (RF GSE) was developed using a ground station receiver similar to what will be used in flight and whose capabilities provided clarity into RF system performance that was previously not obtained until compatibility testing with the ground segments. The Van Allen Probes underwent EMC, acoustic, vibration, and thermal vacuum testing at the environmental test facilities at APL. During this time the RF communication system was rigorously tested to ensure optimal performance, including system-level testing down to threshold power levels. Compatibility tests were performed with the JHU/APL Satellite Communication Facility (SCF), the Universal Space Network (USN), and the Tracking and Data Relay Satellite System (TDRSS). Successful completion of this program as described in this paper validated the design of the system and demonstrated that it will be able to me

Cylinders and Seances: Elise van Calcar and the Spirit of Froebel

ERIC Educational Resources Information Center

Bakker, Nelleke

2013-01-01

This essay discusses the life and work of Elise van Calcar (1822-1904), a writer and maternal feminist who introduced Froebel's kindergarten in the Netherlands. Van Calcar also was the leader of a Christian branch of spiritualism. The focus is pointed at parallels between her reading of Froebel and of "messages" from spirits in the…

15 CFR 30.26 - Reporting of vessels, aircraft, cargo vans, and other carriers and containers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... vehicles, trailers, pallets, cargo vans, lift vans, or similar shipping containers are not considered... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Reporting of vessels, aircraft, cargo vans, and other carriers and containers. 30.26 Section 30.26 Commerce and Foreign Trade Regulations...

15 CFR 30.26 - Reporting of vessels, aircraft, cargo vans, and other carriers and containers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... vehicles, trailers, pallets, cargo vans, lift vans, or similar shipping containers are not considered... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Reporting of vessels, aircraft, cargo vans, and other carriers and containers. 30.26 Section 30.26 Commerce and Foreign Trade Regulations...

15 CFR 30.26 - Reporting of vessels, aircraft, cargo vans, and other carriers and containers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... vehicles, trailers, pallets, cargo vans, lift vans, or similar shipping containers are not considered... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Reporting of vessels, aircraft, cargo vans, and other carriers and containers. 30.26 Section 30.26 Commerce and Foreign Trade Regulations...

15 CFR 30.26 - Reporting of vessels, aircraft, cargo vans, and other carriers and containers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... vehicles, trailers, pallets, cargo vans, lift vans, or similar shipping containers are not considered... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Reporting of vessels, aircraft, cargo vans, and other carriers and containers. 30.26 Section 30.26 Commerce and Foreign Trade Regulations...

15 CFR 30.26 - Reporting of vessels, aircraft, cargo vans, and other carriers and containers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... vehicles, trailers, pallets, cargo vans, lift vans, or similar shipping containers are not considered... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Reporting of vessels, aircraft, cargo vans, and other carriers and containers. 30.26 Section 30.26 Commerce and Foreign Trade Regulations...

Dynamical screening of the van der Waals interaction between graphene layers.

PubMed

Dappe, Y J; Bolcatto, P G; Ortega, J; Flores, F

2012-10-24

The interaction between graphene layers is analyzed combining local orbital DFT and second order perturbation theory. For this purpose we use the linear combination of atomic orbitals-orbital occupancy (LCAO-OO) formalism, that allows us to separate the interaction energy as the sum of a weak chemical interaction between graphene layers plus the van der Waals interaction (Dappe et al 2006 Phys. Rev. B 74 205434). In this work, the weak chemical interaction is calculated by means of corrected-LDA calculations using an atomic-like sp(3)d(5) basis set. The van der Waals interaction is calculated by means of second order perturbation theory using an atom-atom interaction approximation and the atomic-like-orbital occupancies. We also analyze the effect of dynamical screening in the van der Waals interaction using a simple model. We find that this dynamical screening reduces by 40% the van der Waals interaction. Taking this effect into account, we obtain a graphene-graphene interaction energy of 70 ± 5 meV/atom in reasonable agreement with the experimental evidence.

Surgical management of lateral incisor with type II dens invaginatus and a periapical pathosis: A case report with 1-year follow-up.

PubMed

Lakshmi, V Naga; Varma, K Madhu; Sajjan, Girija S; Rambabu, Tanikonda

2017-01-01

Dens invaginatus is a relatively common dental malformation resulting from an infolding of enamel organ into the dental papilla varying in depth into the tooth tissues. Complex morphological anatomy associated with the pulpal pathology presents inaccessibility to completely remove the necrotic pulp tissues and hence poses challenges in rendering endodontic treatment. A combination of nonsurgical and surgical management in treating such cases is advisable depending on the presented variations. The present case reports the surgical endodontic treatment of an immature maxillary lateral incisor with type II dens invaginatus and periapical pathology.

Surgical management of lateral incisor with type II dens invaginatus and a periapical pathosis: A case report with 1-year follow-up

PubMed Central

Lakshmi, V. Naga; Varma, K. Madhu; Sajjan, Girija S.; Rambabu, Tanikonda

2017-01-01

Dens invaginatus is a relatively common dental malformation resulting from an infolding of enamel organ into the dental papilla varying in depth into the tooth tissues. Complex morphological anatomy associated with the pulpal pathology presents inaccessibility to completely remove the necrotic pulp tissues and hence poses challenges in rendering endodontic treatment. A combination of nonsurgical and surgical management in treating such cases is advisable depending on the presented variations. The present case reports the surgical endodontic treatment of an immature maxillary lateral incisor with type II dens invaginatus and periapical pathology. PMID:28761255

Particle Energization in Earth's Van Allen Radiation Belts Due to Solar Wind Forcing

NASA Astrophysics Data System (ADS)

Baker, D. N.

2017-12-01

Early observations of the Earth's radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. However, recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed unexpected properties of the radiation belts, especially for electrons at highly relativistic (E > 2 MeV) and ultra-relativistic (E > 5 MeV) kinetic energies. In this presentation we show using high spatial and temporal resolution data from the experiments on board the Van Allen Probes that multiple belts can exist concurrently and that an exceedingly sharp inner boundary exists for ultra-relativistic electrons. Using additionally available Van Allen Probes data, we demonstrate that these remarkable features of energetic electrons are driven by strong solar and solar wind forcings. The comprehensive Van Allen Probes data show more broadly and in many ways how extremely high energy particles are accelerated, transported, and lost in the magnetosphere due to interplanetary shock wave interactions, coronal mass ejection impacts, and high-speed solar wind streams. The new data have shown especially how dayside processes play a key role in electron acceleration and loss processes.

Martin Van Buren's "Return to the Soil." Teaching with Historic Places.

ERIC Educational Resources Information Center

National Register of Historic Places, Washington, DC. Interagency Resources Div.

Using primary documents, maps, and visual data, this lesson packet focuses on Martin Van Buren and his retirement home, Lindenwald, which is on the National Register of Historic Places. The lesson materials compliment classroom study of early 19th century politics by tracing the life of Martin Van Buren and his role in the Jacksonian Era. Included…

Relationship of the Van Herick Grading System with Peripheral Iris Configuration and Level of Iris Insertion.

PubMed

Khan, Faisal Aziz; Niazi, Shafaq Pervez Khan; Khan, Assad Zaman

2017-09-01

To determine the relationship of the van Herick angle grading system with the level of iris insertion and peripheral iris configuration. Observational study. Eye department, Combined Military Hospital, Malir Cantt., Karachi, from May to October 2015. Sixty-five eyes of 65 patients were recruited. Anterior chamber depth at the temporal limbus was measured as a fraction of corneal section thickness using van Herick technique and graded on the standard 4-point scale of the van Herick grading system. Gonioscopy of the temporal quadrant was performed with a Posner 4 mirror goniolens and both the true level of iris insertion and peripheral iris configuration were recorded on a 4-point scale so as to equate with the van Herick 4-point grading system. Spearman's rho test was applied to determine the relationship of the van Herick grading system with level of iris root insertion and peripheral iris configuration. Amoderate positive correlation between van Herick grade and peripheral iris configuration was found which was statistically significant (rs=0.42, p < 0.001). Astatistically significant and moderate positive correlation was also detected between van Herick grade and the level of iris insertion (rs=0.45, p < 0.001). The van Herick grade has a moderately positive relationship with the peripheral iris configuration and true level of iris insertion.

NOAA's Van-Based Mobile Atmospheric Emissions Measurement Laboratory

NASA Astrophysics Data System (ADS)

Dube, W. P.; Peischl, J.; Neuman, J. A.; Eilerman, S. J.; Holloway, M.; Roberts, O.; Aikin, K. C.; Ryerson, T. B.

2015-12-01

The Chemical Science Division (CSD) mobile atmospheric emissions measurement laboratory is the second and latest of two mobile measurement vans outfitted for atmospheric sampling by the NOAA Earth System Research Laboratory. In this presentation we will describe the modifications made to this vehicle to provide a versatile and relatively inexpensive instrument platform including: the 2 kW 120 volt instrument power system; battery back-up system; data acquisition system; real-time display; meteorological, directional, and position sensor package; and the typical atmospheric emissions instrument package. The van conversion uses commercially available, off-the-shelf components from the marine and RV industries, thus keeping the costs quite modest.

Dynamical property analysis of fractionally damped van der pol oscillator and its application

NASA Astrophysics Data System (ADS)

Zhong, Qiuhui; Zhang, Chunrui

2012-01-01

In this paper, the fractionally damped van der pol equation was studied. Firstly, the fractionally damped van der pol equation was transformed into a set of integer order equations. Then the Lyapunov exponents diagram was given. Secondly, it was transformed into a set of fractional integral equations and solved by a predictor-corrector method. The time domain diagrams and phase trajectory were used to describe the dynamic behavior. Finally, the fractionally damped van der pol equation was used to detect a weak signal.

Accounting for apparent deviations between calorimetric and van't Hoff enthalpies.

PubMed

Kantonen, Samuel A; Henriksen, Niel M; Gilson, Michael K

2018-03-01

In theory, binding enthalpies directly obtained from calorimetry (such as ITC) and the temperature dependence of the binding free energy (van't Hoff method) should agree. However, previous studies have often found them to be discrepant. Experimental binding enthalpies (both calorimetric and van't Hoff) are obtained for two host-guest pairs using ITC, and the discrepancy between the two enthalpies is examined. Modeling of artificial ITC data is also used to examine how different sources of error propagate to both types of binding enthalpies. For the host-guest pairs examined here, good agreement, to within about 0.4kcal/mol, is obtained between the two enthalpies. Additionally, using artificial data, we find that different sources of error propagate to either enthalpy uniquely, with concentration error and heat error propagating primarily to calorimetric and van't Hoff enthalpies, respectively. With modern calorimeters, good agreement between van't Hoff and calorimetric enthalpies should be achievable, barring issues due to non-ideality or unanticipated measurement pathologies. Indeed, disagreement between the two can serve as a flag for error-prone datasets. A review of the underlying theory supports the expectation that these two quantities should be in agreement. We address and arguably resolve long-standing questions regarding the relationship between calorimetric and van't Hoff enthalpies. In addition, we show that comparison of these two quantities can be used as an internal consistency check of a calorimetry study. Copyright © 2017 Elsevier B.V. All rights reserved.

LEASAT-3 repair during the van Hoften and Fisher EVA

NASA Image and Video Library

1985-08-31

51I-44-012 (1 Sept. 1985) --- Astronaut James D. van Hoften looks on as the Syncom IVC-3 satellite responds to his push against it moments earlier. Dr. van Hoften, mission specialist, is anchored to a foot restraint on the end of the remote manipulator system (RMS) arm of the Earth-orbiting space shuttle Discovery. The 51-I crew members showed this photograph at their Sept. 11 postflight press conference. Photo credit: NASA

Motivational Factors in Telecollaborative Exchanges among Teenagers

ERIC Educational Resources Information Center

Jauregi, Kristi; Melchor-Couto, Sabela

2017-01-01

Motivational factors play an important role in (language) learning processes and research indicates that this is also true for telecollaboration exchanges (Jauregi, de Graaff, van den Bergh, & Kriz, 2012; Melchor-Couto, 2017; in press). This short paper will introduce a study into how motivational factors play a role in telecollaboration…

Innovative Research-Based Approaches to Learning and Teaching. OECD Education Working Papers, No. 79

ERIC Educational Resources Information Center

van den Broek, Gesa Sonja Elsa

2012-01-01

Building on an earlier 2008 summary prepared for OECD by Marlene Scardamalia and Carl Bereiter, this paper by Gesa S. E. van den Broek provides a more extensive discussion of approaches described as "research based innovation." "Fostering Communities of Learning" is a constructivist approach in which teachers help students discover important…

The Synthesis of Single-Subject Experimental Data: Extensions of the Basic Multilevel Model

ERIC Educational Resources Information Center

Van den Noortgate, Wim; Moeyaert, Mariola; Ugille, Maaike; Beretvas, Tasha; Ferron, John

2014-01-01

Due to an increasing interest in the use of single-subject experimental designs (SSEDs), appropriate techniques are needed to analyze this type of data. The purpose of this paper proposal is to present four studies (Beretvas, Hembry, Van den Noortgate, & Ferron, 2013; Bunuan, Hembry & Beretvas, 2013; Moeyaert, Ugille, Ferron, Beretvas,…

Factorial Temperament Structure in Stuttering, Voice-Disordered, and Typically Developing Children

ERIC Educational Resources Information Center

Eggers, Kurt; De Nil, Luc F.; Van den Bergh, Bea R. H.

2009-01-01

Purpose: The purpose of this study was to determine whether the underlying temperamental structure of the Dutch Children's Behavior Questionnaire (CBQ; B. Van den Bergh & M. Ackx, 2003) was identical for children who stutter (CWS), typically developing children (TDC), and children with vocal nodules (CWVN). Method: A principal axis factor…

A brief overview of current relationships of geography, statistics, and taxonomy with the classical integrated control concept

USDA-ARS?s Scientific Manuscript database

A classic paper on the integrated control concept appeared in the later part of the 1950’s, led by Vernon Stern, Ray Smith, Robert van den Bosch, and Kenneth Hagen. Numerous concepts and definitions were formulated at that time. In this presentation, a short philosophical summary will be presented...

Flexible Strategy Use by Students Who Learn Much versus Little from Text: Transitions within Think-Aloud Protocols

ERIC Educational Resources Information Center

Cromley, Jennifer G.; Wills, Theodore W.

2016-01-01

Van den Broek's landscape model explicitly posits sequences of moves during reading in real time. Two other models that implicitly describe sequences of processes during reading are tested in the present research. Coded think-aloud data from 24 undergraduate students reading scientific text were analysed with lag-sequential techniques to compare…

Coherence Threshold and the Continuity of Processing: The RI-Val Model of Comprehension

ERIC Educational Resources Information Center

O'Brien, Edward J.; Cook, Anne E.

2016-01-01

Common to all models of reading comprehension is the assumption that a reader's level of comprehension is heavily influenced by their standards of coherence (van den Broek, Risden, & Husbye-Hartman, 1995). Our discussion focuses on a subcomponent of the readers' standards of coherence: the coherence threshold. We situate this discussion within…

Analysis of crashes involving 15-passenger vans

DOT National Transportation Integrated Search

2004-05-01

This study explores the relationship between vehicle occupancy and several other variables in the National Highway Traffic Safety Administration's (NHTSA's) Fatality Analysis Reporting System (FARS) database and a 15-passenger van's risk of rollover....

A note on evaluating VAN earthquake predictions

NASA Astrophysics Data System (ADS)

Tselentis, G.-Akis; Melis, Nicos S.

The evaluation of the success level of an earthquake prediction method should not be based on approaches that apply generalized strict statistical laws and avoid the specific nature of the earthquake phenomenon. Fault rupture processes cannot be compared to gambling processes. The outcome of the present note is that even an ideal earthquake prediction method is still shown to be a matter of a “chancy” association between precursors and earthquakes if we apply the same procedure proposed by Mulargia and Gasperini [1992] in evaluating VAN earthquake predictions. Each individual VAN prediction has to be evaluated separately, taking always into account the specific circumstances and information available. The success level of epicenter prediction should depend on the earthquake magnitude, and magnitude and time predictions may depend on earthquake clustering and the tectonic regime respectively.

Critical lines for an unequal size of molecules in a binary gas-liquid mixture around the van Laar point using the combination of the Tompa model and the van der Waals equation.

PubMed

Gençaslan, Mustafa; Keskin, Mustafa

2012-02-14

We combine the modified Tompa model with the van der Waals equation to study critical lines for an unequal size of molecules in a binary gas-liquid mixture around the van Laar point. The van Laar point is coined by Meijer and it is the only point at which the mathematical double point curve is stable. It is the intersection of the tricritical point and the double critical end point. We calculate the critical lines as a function of χ(1) and χ(2), the density of type I molecules and the density of type II molecules for various values of the system parameters; hence the global phase diagrams are presented and discussed in the density-density plane. We also investigate the connectivity of critical lines at the van Laar point and its vicinity and discuss these connections according to the Scott and van Konynenburg classifications. It is also found that the critical lines and phase behavior are extremely sensitive to small modifications in the system parameters. © 2012 American Institute of Physics

Van Vleck and the magnetic susceptibilities of gaseous molecules

NASA Astrophysics Data System (ADS)

Meyer, Horst

2011-03-01

In his 1927 Physical Review article and in his 1932 book, ~The Theory of Electric and Magnetic Susceptibilities,~Van Vleck used the new quantum theory to derive the magnetic susceptibilities of O2 and NO in their gaseous form ~and compared them with experiments. ~He was therefore very interested in low temperature susceptibility experiments on O2 at Oxford University in 1954 where individual O2 molecules were trapped in small, almost spherical cages in organic clathrates. Correspondence between him and this speaker, then at Oxford, led to further measurements of O2 and also of NO in such clathrates, to theory and to subsequent publications and correspondence. Later communication with Van Vleck on the magnetism in rare earth iron garnets, a subject of long-term interest to him, will be described ~in connection with experiments carried out at Duke University. Some fond personal ~recollections of this speaker of his interaction with Van Vleck - both while at Harvard, during visits and through correspondence which extended into the seventies - will be presented.

Early Childhood Matters: The Bulletin of the Bernard van Leer Foundation, 1999.

ERIC Educational Resources Information Center

Smale, Jim, Ed.

1999-01-01

This document consists of the three 1999 issues of The Bernard van Leer Foundation's "Early Childhood Matters." This periodical, addressed to practitioners in the field of early childhood education, evolved from an in-house publication directed to projects funded by the Bernard van Leer Foundation. Articles in the February 1999 edition…

Early Childhood Matters: The Bulletin of the Bernard van Leer Foundation, 1998.

ERIC Educational Resources Information Center

Smale, Jim, Ed.

1998-01-01

This document consists of the three 1998 issues of The Bernard van Leer Foundations'"Early Childhood Matters." This periodical, addressed to practitioners in the field of early childhood development, evolved from an in-house publication directed to projects funded by the Bernard van Leer Foundation. Articles in the February 1998 edition…

Early Childhood Matters: The Bulletin of the Bernard van Leer Foundation, 2000.

ERIC Educational Resources Information Center

Smale, Jim, Ed.

2000-01-01

This document consists of the three 2000 issues of The Bernard van Leer Foundation's "Early Childhood Matters." This periodical, addressed to practitioners in the field of early childhood education, evolved from an in-house publication directed to projects funded by the Bernard van Leer Foundation. Articles in the February 2000 edition…

77 FR 44683 - Phillips-Van Heusen Corporation, IZOD Dress Furnishings Division, New York, NY; Notice of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

... for Reconsideration for the workers and former workers of Phillips-Van Heusen Corporation, IZOD Women... Phillips-Van Heusen Corporation, IZOD Women's Wholesale Division, New York, New York has not increased. In... Phillips-Van Heusen Corporation, IZOD Women's Wholesale Division, New York, New York) was incorrect, that...

Atomically thin p-n junctions with van der Waals heterointerfaces.

PubMed

Lee, Chul-Ho; Lee, Gwan-Hyoung; van der Zande, Arend M; Chen, Wenchao; Li, Yilei; Han, Minyong; Cui, Xu; Arefe, Ghidewon; Nuckolls, Colin; Heinz, Tony F; Guo, Jing; Hone, James; Kim, Philip

2014-09-01

Semiconductor p-n junctions are essential building blocks for electronic and optoelectronic devices. In conventional p-n junctions, regions depleted of free charge carriers form on either side of the junction, generating built-in potentials associated with uncompensated dopant atoms. Carrier transport across the junction occurs by diffusion and drift processes influenced by the spatial extent of this depletion region. With the advent of atomically thin van der Waals materials and their heterostructures, it is now possible to realize a p-n junction at the ultimate thickness limit. Van der Waals junctions composed of p- and n-type semiconductors--each just one unit cell thick--are predicted to exhibit completely different charge transport characteristics than bulk heterojunctions. Here, we report the characterization of the electronic and optoelectronic properties of atomically thin p-n heterojunctions fabricated using van der Waals assembly of transition-metal dichalcogenides. We observe gate-tunable diode-like current rectification and a photovoltaic response across the p-n interface. We find that the tunnelling-assisted interlayer recombination of the majority carriers is responsible for the tunability of the electronic and optoelectronic processes. Sandwiching an atomic p-n junction between graphene layers enhances the collection of the photoexcited carriers. The atomically scaled van der Waals p-n heterostructures presented here constitute the ultimate functional unit for nanoscale electronic and optoelectronic devices.

Phenotypic and genotypic characterization of vancomycin-resistant Enterococcus faecium clinical isolates from two hospitals in Mexico: First detection of VanB phenotype-vanA genotype.

PubMed

Bocanegra-Ibarias, Paola; Flores-Treviño, Samantha; Camacho-Ortiz, Adrián; Morfin-Otero, Rayo; Villarreal-Treviño, Licet; Llaca-Díaz, Jorge; Martínez-Landeros, Erik Alan; Rodríguez-Noriega, Eduardo; Calzada-Güereca, Andrés; Maldonado-Garza, Héctor Jesús; Garza-González, Elvira

2016-01-01

Enterococcus faecium has emerged as a multidrug-resistant nosocomial pathogen involved in outbreaks worldwide. Our aim was to determine the antimicrobial susceptibility, biofilm production, and clonal relatedness of vancomycin-resistant E. faecium (VREF) clinical isolates from two hospitals in Mexico. Consecutive clinical isolates (n=56) were collected in two tertiary care hospitals in Mexico from 2011 to 2014. VREF isolates were characterized by phenotypic and molecular methods including pulsed-field gel electrophoresis (PFGE). VREF isolates were highly resistant to vancomycin, erythromycin, norfloxacin, high-level streptomycin, and teicoplanin, and showed lower resistance to tetracycline, nitrofurantoin and quinupristin-dalfopristin. None of the isolates were resistant to linezolid. The vanA gene was detected in all isolates. Two VanB phenotype-vanA genotype isolates, highly resistant to vancomycin and susceptible to teicoplanin, were detected. Furthermore, 17.9% of the isolates were classified as biofilm producers, and the espfm gene was found in 98.2% of the isolates. A total of 37 distinct PFGE patterns and 6 clones (25% of the isolates as clone A, 5.4% as clone B, and 3.6% each as clone C, D, E, and F) were detected. Clone A was detected in 5 different wards of the same hospital during 14 months of surveillance. The high resistance to most antimicrobial agents and the moderate cross-transmission of VREF detected accentuates the need for continuous surveillance of E. faecium in the hospital setting. This is also the first reported incidence of the E. faecium VanB phenotype-vanA genotype in the Americas. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

The Sacred Child Project: A New Definition of "Formal" Services.

ERIC Educational Resources Information Center

Eagle, John; Painte, Deborah; Paulson, Susan; Young Bird, Mike

1999-01-01

Reviews the Sacred Child Project in North Dakota, a tribally developed version of the wraparound process. The effort combines contemporary human services with the spiritual and cultural wisdom of the tribes. The article is based on an interview and conversation between the authors and John VanDenBerg, a wraparound consultant. (Author/GCP)

How to Measure and Explain Achievement Change in Large-Scale Assessments: A Rejoinder

ERIC Educational Resources Information Center

Hickendorff, Marian; Heiser, Willem J.; van Putten, Cornelis M.; Verhelst, Norman D.

2009-01-01

In this rejoinder, we discuss substantive and methodological validity issues of large-scale assessments of trends in student achievement, commenting on the discussion paper by Van den Heuvel-Panhuizen, Robitzsch, Treffers, and Koller (2009). We focus on methodological challenges in deciding what to measure, how to measure it, and how to foster…

Auditory Attentional Set-Shifting and Inhibition in Children Who Stutter

ERIC Educational Resources Information Center

Eggers, Kurt; Jansson-Verkasalo, Eira

2017-01-01

Purpose: The purpose of this study was to investigate whether previously reported parental questionnaire-based differences in attentional shifting and inhibitory control (AS and IC; Eggers, De Nil, & Van den Bergh, 2010) would be supported by direct measurement of AS and IC using a computer task. Method: Participants were 16 Finnish children…

Bernard van Leer Foundation Newsletter, 1996.

ERIC Educational Resources Information Center

Bernard van Leer Foundation, Newsletter, 1996

1996-01-01

This document consists of the four issues of the Bernard van Leer Foundation's "Newsletter" published during 1996. The newsletter covers topics related to, or about efforts to foster, the education and welfare of children around the world, and includes descriptions of programs around the world, lists of resources and publications, and…

Transcriptional Analysis of the vanC Cluster from Enterococcus gallinarum Strains with Constitutive and Inducible Vancomycin Resistance

PubMed Central

Panesso, Diana; Abadía-Patiño, Lorena; Vanegas, Natasha; Reynolds, Peter E.; Courvalin, Patrice; Arias, Cesar A.

2005-01-01

The vanC glycopeptide resistance gene cluster encodes enzymes required for synthesis of peptidoglycan precursors ending in d-Ala-d-Ser. Enterococcus gallinarum BM4174 and SC1 are constitutively and inducibly resistant to vancomycin, respectively. Analysis of peptidoglycan precursors in both strains indicated that UDP-MurNAc-tetrapeptide and UDP-MurNAc-pentapeptide[d-Ser] were synthesized in E. gallinarum SC1 only in the presence of vancomycin (4 μg/ml), whereas the “resistance” precursors accumulated in the cytoplasm of BM4174 cells under both inducing and noninducing conditions. Northern hybridization and reverse transcription-PCR experiments revealed that all the genes from the cluster, vanC-1, vanXYC, vanT, vanRC, and vanSC, were transcribed from a single promoter. In the inducible SC1 isolate, transcriptional regulation appeared to be responsible for inducible expression of resistance. Promoter mapping in E. gallinarum BM4174 revealed that the transcriptional start site was located 30 nucleotides upstream from vanC-1 and that the −10 promoter consensus sequence had high identity with that of the vanA cluster. Comparison of the deduced sequence of the vanSC genes from isolates with constitutive and inducible resistance revealed several amino acid substitutions located in the X box (R200L) and in the region between the F and G2 boxes (D312N, D312A, and G320S) of the putative sensor kinase proteins from isolates with constitutive resistance. PMID:15728903

Baseline tests of the Volkswagen transporter electric delivery van

NASA Technical Reports Server (NTRS)

Soltis, R. F.; Mcbrien, E. F.; Bozek, J. M.; Gourash, F.

1978-01-01

The Volkswagen Transporter, an electric delivery van, was tested as part of an Energy Research and Development Administration (ERDA) project to characterize the state of the art of electric vehicles. The Volkswagen Transporter is a standard Volkswagen van that has been converted to an electric vehicle. It is powered by a 144-volt traction battery. A direct current (dc) chopper controller, actuated by a conventional accelerator pedal, regulates the voltage or power applied to the 16-kilowatt (21-hp) motor. The braking system uses conventional hydraulic braking in combination with an electric regenerative braking system. The Volkswagen vehicle performance test results are presented.

The van Gogh of the Infrared Sky

NASA Image and Video Library

2011-04-25

NASA Wide-field Infrared Survey Explorer is a little like the Vincent van Gogh of the infrared sky, providing the world with picturesque images of the cosmos by representing infrared light through color. This image is the nebula NGC 2174.

Eisen voor Buitenbeelden van Voertuigsimulatoren: Een Literatuurstudie (Use of Exterior Pictures in Vehicle Simulators: A Literature Survey)

DTIC Science & Technology

1991-06-01

1.3 Opleiding en onderzoek met voertuigsimulatoren 9 1.4 Opbouw van simulatoren 11 1.5 Totstandkomning van beelden in CGI-systemen 13 1.6 Bepalen van...pictures in vehicle simulators. A literature survey s 029 9 20 Aantal bladzijden: 102 .JISTRIBIYI±WN- STATEMEN9 -2 39 Approved for public release; 2 28 9 ...Achteruitkijkspiegels en verrekijkers 79 8.2 Helderheidsversterkers en warmtebeelden 80 8.3 Middelen om afstand te bepalen 80 9 INTERACTIES VAN HET

Den use and activity patterns in female Canada lynx (Lynx Canadensis) in the northern Rocky Mountains

Treesearch

Lucretia E. Olson; John R. Squires; Nicholas J. DeCesare; Jay A. Kolbe

2011-01-01

Knowledge of female behavior while rearing young can have important implications for species conservation. We located dens and analyzed activity (defined as movement between consecutive GPS locations) for nine female lynx with kittens in the northcentral Rocky Mountains in 2005 and 2007. We used GPS tracking collars to quantify the percentage of time a female spent...

Van, Turkey Earthquake of 23 October 2011, Mw 7.2; An Overview on Disaster Management

PubMed Central

ZARÉ, Mehdi; NAZMAZAR, Behnaz

2013-01-01

An earthquake was happened on 23 October 2011 in Van, Turkey (Mw7.2) at the eastern most area of Anatolian plateau and in the neighborhood of Iranian border (West Azerbaijan Province). The study was performed based on field and office observations and has been focused on the process of disaster management in Turkey after the 23 October 2011 earthquake. We surveyed the quake from the view point of disaster management, and study the relief process during and after the catastrophe. The day-to-day disaster management procedure in seventeen days after the event has been scrutinized as well. The number of victims and extent of damage in Van earthquake was relatively limited according to the national experiences and recent modernization of infrastructures in Turkey. The Van earthquake caused 644 deaths and demolishing of several buildings in the cities of Van and Erciş in Van Province. The performance of the government organizations is however criticized based on their response to the event. PMID:23515082

Resonance oscillations of nonreciprocal long-range van der Waals forces between atoms in electromagnetic fields

NASA Astrophysics Data System (ADS)

Sherkunov, Yury

2018-03-01

We study theoretically the van der Waals interaction between two atoms out of equilibrium with an isotropic electromagnetic field. We demonstrate that at large interatomic separations, the van der Waals forces are resonant, spatially oscillating, and nonreciprocal due to resonance absorption and emission of virtual photons. We suggest that the van der Waals forces can be controlled and manipulated by tuning the spectrum of artificially created random light.

Q & A with Carmella Van Vleet

ERIC Educational Resources Information Center

Curriculum Review, 2008

2008-01-01

This article presents an interview with Carmella Van Vleet, a former teacher and educational speaker. She has written family humor and parenting articles, and is also the author of "How to Handle School Snafus," "Great Ancient Egypt Projects You Can Build Yourself" and "Amazing Ben Franklin Inventions You Can Build Yourself." In this interview,…

Investigating the Effect of van Hiele Phase-Based Instruction on Pre-Service Teachers' Geometric Thinking

ERIC Educational Resources Information Center

Armah, Robert Benjamin; Cofie, Primrose Otokonor; Okpoti, Christopher Adjei

2018-01-01

This study investigated the effect of van Hiele Phase-based Instruction (VHPI) on Ghanaian Pre-service Teachers' (PTs') geometric thinking in terms of the van Hiele Levels. A pre-test post-test quasi-experimental design was employed. There were 75 PTs each in the experimental group and the control group. Van Hiele Geometry Test (VHGT) was…

Manipulating Task Implementation Variables with Incipient Spanish Language Learners: A Classroom-Based Study

ERIC Educational Resources Information Center

Payant, Caroline; Reagan, Derek

2018-01-01

A growing body of research has shown a positive role of task-supported instruction in second language (L2) learning (Ellis, 2003a; Loewen, 2015; Van Den Branden, 2006). From a pedagogical perspective, recycling or repeating parts of teaching materials is common practice and theoretical support for such practice is emerging (Bygate and Samuda,…

Inhibitory Control in Childhood Stuttering

ERIC Educational Resources Information Center

Eggers, Kurt; De Nil, Luc F.; Van den Bergh, Bea R. H.

2013-01-01

Purpose: The purpose of this study was to investigate whether previously reported parental questionnaire-based differences in inhibitory control (IC; Eggers, De Nil, & Van den Bergh, 2010) would be supported by direct measurement of IC using a computer task. Method: Participants were 30 children who stutter (CWS; mean age = 7;05 years) and 30…

Evidence of van Hove singularities in ordered grain boundaries of graphene.

PubMed

Ma, Chuanxu; Sun, Haifeng; Zhao, Yeliang; Li, Bin; Li, Qunxiang; Zhao, Aidi; Wang, Xiaoping; Luo, Yi; Yang, Jinlong; Wang, Bing; Hou, J G

2014-06-06

It has long been under debate whether the electron transport performance of graphene could be enhanced by the possible occurrence of van Hove singularities in grain boundaries. Here, we provide direct experimental evidence to confirm the existence of van Hove singularity states close to the Fermi energy in certain ordered grain boundaries using scanning tunneling microscopy. The intrinsic atomic and electronic structures of two ordered grain boundaries, one with alternative pentagon and heptagon rings and the other with alternative pentagon pair and octagon rings, are determined. It is firmly verified that the carrier concentration and, thus, the conductance around ordered grain boundaries can be significantly enhanced by the van Hove singularity states. This finding strongly suggests that a graphene nanoribbon with a properly embedded ordered grain boundary can be a promising structure to improve the performance of graphene-based electronic devices.

Concurrent Van der Woude syndrome and Turner syndrome: A case report.

PubMed

Los, Evan; Baines, Hayley; Guttmann-Bauman, Ines

2017-01-01

Most cases of Van der Woude syndrome are caused by a mutation to interferon regulatory factor 6 on chromosome 1. Turner syndrome is caused by complete or partial absence of the second sex chromosome in girls. We describe a unique case of the two syndromes occurring concurrently though apparently independently in a girl with Van der Woude syndrome diagnosed at birth and Turner syndrome at 14 years 9 months. Short stature was initially misattributed to Van der Woude syndrome and pituitary insufficiency associated with clefts before correctly diagnosing Turner syndrome. We discuss the prevalence of delayed diagnosis of Turner syndrome, the rarity of reports of concurrent autosomal chromosome mutation and sex chromosome deletion, as well as the need to consider the diagnosis of Turner syndrome in all girls with short stature regardless of prior medical history.

Geologic environment of the Van Norman Reservoirs area

USGS Publications Warehouse

Yerkes, R.F.; Bonilla, M.G.; Youd, T.L.; Sims, J.D.

1974-01-01

The upper and lower Van Norman dams, in northwesternmost San Fernando Valley about 20 mi (32 km) northwest of downtown Los Angeles, were severely damaged during the 1971 San Fernando earthquake. An investigation of the geologic-seismologic setting of the Van Norman area indicates that an earthquake of at least M 7.7 may be expected in the Van Norman area. The expectable transitory effects in the Van Norman area of such an earthquake are as follows: peak horizontal acceleration of at least 1.15 g, peak velocity of displacement of 4.43 ft/sec (135 cm/sec), peak displacement of 2.3 ft (70 cm), and duration of shaking at accelerations greater than 0.05 g, 40 sec. A great earthquake (M 8+) on the San Andreas fault, 25 mi distant, also is expectable. Transitory effects in the Van Norman area from such an earthquake are estimated as follows: peak horizontal acceleration of 0.5 g, peak velocity of 1.97 ft/sec (60 cm/sec), displacement of 1.31 ft (40 cm), and duration of shaking at accelerations greater than 0.05 g, 80 sec. The permanent effects of the expectable local earthquake could include simultaneous fault movement at the lower damsite, the upper damsite, and the site proposed for a replacement dam halfway between the upper and lower dams. The maximum differential displacements due to such movements are estimated at 16.4 ft (5 m) at the lower damsite and about 9.6 ft (2.93 m) at the upper and proposed damsites. The 1971 San Fernando earthquake (M 6?) was accompanied by the most intense ground motions ever recorded instrumentally for a natural earthquake. At the lower Van Norman dam, horizontal accelerations exceeded 0.6 g, and shaking greater than 0.25 g lasted for about 13 see; at Pacoima dam, 6 mi (10 km) northeast of the lower dam, high-frequency peak horizontal accelerations of 1.25 g were recorded in two directions, and shaking greater than 0.25 g lasted for about 7 sec. Permanent effects of the earthquake include slope failures in the embankments of the upper

Van Allen Probes Science Gateway: A Centralized Data Access Point

NASA Astrophysics Data System (ADS)

Romeo, G.; Barnes, R. J.; Ukhorskiy, A. Y.; Sotirelis, T.; Stephens, G. K.; Kessel, R.; Potter, M.

2015-12-01

The Van Allen Probes Science Gateway acts a centralized interface to the instrument Science Operation Centers (SOCs), provides mission planning tools, and hosts a number of science related activities such as the mission bibliography. Most importantly, the Gateway acts as the primary site for processing and delivering the Van Allen Probes Space Weather data to users. Over the past years, the web-site has been completely redesigned with the focus on easier navigation and improvements of the existing tools such as the orbit plotter, position calculator and magnetic footprint tool. In addition, a new data plotting facility has been added. Based on HTML5, which allows users to interactively plot Van Allen Probes science and space weather data. The user can tailor the tool to display exactly the plot they wish to see and then share this with other users via either a URL or by QR code. Various types of plots can be created, including, simple time series, data plotted as a function of orbital location, and time versus L-Shell, capability of visualizing data from both probes (A & B) on the same plot. In cooperation with all Van Allen Probes Instrument SOCs, the Science Gateway will soon be able to serve higher level data products (Level 3), and to visualize them via the above mentioned HTML5 interface. Users will also be able to create customized CDF files on the fly.

Patterns of Cellular Immunity Associated with Experimental Infection with rDEN2Δ30 (Tonga/74) Support Its Suitability as a Human Dengue Virus Challenge Strain

PubMed Central

Grifoni, Alba; Angelo, Michael; Sidney, John; Paul, Sinu; Peters, Bjoern; de Silva, Aruna D.; Phillips, Elizabeth; Mallal, Simon; Diehl, Sean A.; Botten, Jason; Boyson, Jonathan; Kirkpatrick, Beth D.; Whitehead, Stephen S.; Durbin, Anna P.; Sette, Alessandro

2017-01-01

ABSTRACT A deletion variant of the dengue virus (DENV) serotype 2 (DENV2) Tonga/74 strain lacking 30 nucleotides from its 3′ untranslated region (rDEN2Δ30) has previously been established for use in a controlled human DENV challenge model. To evaluate if this model is appropriate for the derivation of correlates of protection for DENV vaccines on the basis of cellular immunity, we wanted to compare the cellular immune response to this challenge strain to the response induced by natural infection. To achieve this, we predicted HLA class I- and class II-restricted peptides from rDEN2Δ30 and used them in a gamma interferon enzyme-linked immunosorbent spot assay to interrogate CD8+ and CD4+ T cell responses in healthy volunteers infected with rDEN2Δ30. At the level of CD8 responses, vigorous ex vivo responses were detected in approximately 80% of donors. These responses were similar in terms of the magnitude and the numbers of epitopes recognized to the responses previously observed in peripheral blood mononuclear cells from donors from regions where DENV is hyperendemic. The similarity extended to the immunodominance hierarchy of the DENV nonstructural proteins, with NS3, NS5, and NS1 being dominant in both donor cohorts. At the CD4 level, the responses to rDEN2Δ30 vaccination were less vigorous than those to natural DENV infection and were more focused on nonstructural proteins. The epitopes recognized following rDEN2Δ30 infection and natural infection were largely overlapping for both the CD8 (100%) and CD4 (85%) responses. Finally, rDEN2Δ30 induced stronger CD8 responses than other, more attenuated DENV isolates. IMPORTANCE The lack of a known correlate of protection and the failure of a neutralizing antibody to correlate with protection against dengue virus have highlighted the need for a human DENV challenge model to better evaluate the candidate live attenuated dengue vaccines. In this study, we sought to characterize the immune profiles of rDEN2Δ30

Presence of the resistance genes vanC1 and pbp5 in phenotypically vancomycin and ampicillin susceptible Enterococcus faecalis.

PubMed

Schwaiger, Karin; Bauer, Johann; Hörmansdorfer, Stefan; Mölle, Gabriele; Preikschat, Petra; Kämpf, Peter; Bauer-Unkauf, Ilse; Bischoff, Meike; Hölzel, Christina

2012-08-01

Ampicillin and vancomycin are important antibiotics for the therapy of Enterococcus faecalis infections. The ampicillin resistance gene pbp5 is intrinsic in Enterococcus faecium. The vanC1 gene confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Both genes are chromosomally located. Resistance to ampicillin and vancomycin was determined in 484 E. faecalis of human and porcine origin by microdilution. Since E. faecalis are highly skilled to acquire resistance genes, all strains were investigated for the presence of pbp5 (and, in positive strains, for the penicillin-binding protein synthesis repressor gene psr) and vanC1 (and, in positive strains, for vanXYc and vanT) by using polymerase chain reaction (PCR). One porcine and one human isolate were phenotypically resistant to ampicillin; no strain was vancomycin resistant. Four E. faecalis (3/1 of porcine/human origin) carried pbp5 (MIC=1 mg/L), and four porcine strains were vanC1 positive (minimum inhibitory concentration [MIC]=1 mg/L). Real-time reverse transcriptase (RT)-PCR revealed that the genes were not expressed. The psr gene was absent in the four pbp5-positive strains; the vanXYc gene was absent in the four vanC1-positive strains. However, vanT of the vanC gene cluster was detected in two vanC1-positive strains. To our knowledge, this is the first report on the presence of pbp5, identical with the "E. faecium pbp5 gene," and of vanC1/vanT in E. faecalis. Even if resistance is not expressed in these strains, this study shows that E. faecalis have a strong ability to acquire resistance genes-and potentially to spread them to other bacteria. Therefore, close monitoring of this species should be continued.

Simon van der Meer (1925-2011):. A Modest Genius of Accelerator Science

NASA Astrophysics Data System (ADS)

Chohan, Vinod C.

2011-02-01

Simon van der Meer was a brilliant scientist and a true giant of accelerator science. His seminal contributions to accelerator science have been essential to this day in our quest for satisfying the demands of modern particle physics. Whether we talk of long base-line neutrino physics or antiproton-proton physics at Fermilab or proton-proton physics at LHC, his techniques and inventions have been a vital part of the modern day successes. Simon van der Meer and Carlo Rubbia were the first CERN scientists to become Nobel laureates in Physics, in 1984. Van der Meer's lesserknown contributions spanned a whole range of subjects in accelerator science, from magnet design to power supply design, beam measurements, slow beam extraction, sophisticated programs and controls.

The integrable case of Adler-van Moerbeke. Discriminant set and bifurcation diagram

NASA Astrophysics Data System (ADS)

Ryabov, Pavel E.; Oshemkov, Andrej A.; Sokolov, Sergei V.

2016-09-01

The Adler-van Moerbeke integrable case of the Euler equations on the Lie algebra so(4) is investigated. For the L- A pair found by Reyman and Semenov-Tian-Shansky for this system, we explicitly present a spectral curve and construct the corresponding discriminant set. The singularities of the Adler-van Moerbeke integrable case and its bifurcation diagram are discussed. We explicitly describe singular points of rank 0, determine their types, and show that the momentum mapping takes them to self-intersection points of the real part of the discriminant set. In particular, the described structure of singularities of the Adler-van Moerbeke integrable case shows that it is topologically different from the other known integrable cases on so(4).

Identification of VanN-type vancomycin resistance in an Enterococcus faecium isolate from chicken meat in Japan.

PubMed

Nomura, Takahiro; Tanimoto, Koichi; Shibayama, Keigo; Arakawa, Yoshichika; Fujimoto, Shuhei; Ike, Yasuyoshi; Tomita, Haruyoshi

2012-12-01

Five VanN-type vancomycin-resistant Enterococcus faecium strains were isolated from a sample of domestic chicken meat in Japan. All isolates showed low-level resistance to vancomycin (MIC, 12 mg/liter) and had the same pulsed-field gel electrophoresis profile. The vancomycin resistance was encoded on a large plasmid (160 kbp) and was expressed constitutively. The VanN-type resistance operon was identical to the first resistance operon to be reported, with the exception of a 1-bp deletion in vanT(N) and a 1-bp substitution in vanS(N).

Hemodynamic Changes in Rat Leg Muscles during Tourniquet-induced Ischemia-reperfusion Injury Observed by Near-infrared Spectroscopy

DTIC Science & Technology

2009-07-01

leg muscle during pressure increase (Arbabi et al 1999) and in the human leg muscle during exercise (Breit et al 1997, Egun et al 2002, van den Brand...time of flight measurement. Phys Med Biol 1988;33:1433–42. [PubMed: 3237772] Egun A, Farooq V, Torella F, Cowley R, Thorniley MS, McCollum CN. The

Figures of Disengagement: Charles Taylor, Scientific Parenting, and the Paradox of Late Modernity

ERIC Educational Resources Information Center

Van den Berge, Luc; Ramaekers, Stefan

2014-01-01

In this essay Luc Van den Berge and Stefan Ramaekers take the idea(l) of "scientific parenting" as an example of ambiguities that are typical of our late-modern condition. On the one hand, parenting seems like a natural thing to do, which makes "scientific parenting" sound like an oxymoron; on the other hand, a disengaged…

Multi-millennia simulation of Greenland deglaciation from the Max-Plank-Institute Model (MPI-ISM) 2xCO2 simulation

NASA Astrophysics Data System (ADS)

Cabot, Vincent; Vizcaino, Miren; Mikolajewicz, Uwe

2016-04-01

Long-term ice sheet and climate coupled simulations are of great interest since they assess how the Greenland Ice Sheet (GrIS) will respond to global warming and how GrIS changes will impact on the climate system. We have run the Max-Plank-Institute Earth System Model coupled with an Ice Sheet Model (SICOPOLIS) over a time period of 10500 years under two times CO2 forcing. This is a coupled atmosphere (ECHAM5T31), ocean (MPI-OM), dynamic vegetation (LPJ), and ice sheet (SICOPOLIS, 10 km horizontal resolution) model. Given the multi-millennia simulation, the horizontal spatial resolution of the atmospheric component is relatively coarse (3.75°). A time-saving technique (asynchronous coupling) is used once the global climate reaches quasi-equilibrium. In our doubling-CO2 simulation, the GrIS is expected to break up into two pieces (one ice cap in the far north on one ice sheet in the south and east) after 3000 years. During the first 500 simulation years, the GrIS climate and surface mass balance (SMB) are mainly affected by the greenhouse effect-forced climate change. After the simulated year 500, the global climate reaches quasi-equilibrium. Henceforth Greenland climate change is mainly due to ice sheet decay. GrIS albedo reduction enhances melt and acts as a powerful feedback for deglaciation. Due to increased cloudiness in the Arctic region as a result of global climate change, summer incoming shortwave radiation is substantially reduced over Greenland, reducing deglaciation rates. At the end of the simulation, Greenland becomes green with forest growing over the newly deglaciated regions. References: Helsen, M. M., van de Berg, W. J., van de Wal, R. S. W., van den Broeke, M. R., and Oerlemans, J. (2013), Coupled regional climate-ice-sheet simulation shows limited Greenland ice loss during the Eemian, Climate of the Past, 9, 1773-1788, doi: 10.5194/cp-9-1773-2013 Helsen, M. M., van de Wal, R. S. W., van den Broeke, M. R., van de Berg, W. J., and Oerlemans, J

Mid infrared observations of Van Maanen 2: no substellar companion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farihi, J; Becklin, E; Macintosh, B

2004-11-03

The results of a comprehensive infrared imaging search for the putative 0.06 M{sub {circle_dot}} astrometric companion to the 4.4 pc white dwarf van Mannen 2 are reported. Adaptive optics images acquired at 3.8 {micro}m reveal a diffraction limited core of 0.09 inch and no direct evidence of a secondary. Models predict that at 5 Gyr, a 50 M{sub J} brown dwarf would be only 1 magnitude fainter than van Maanen 2 at this wavelength and the astrometric analysis suggested a separation of 0.2 inch. In the case of a chance alignment along the line of sight, a 0.4 mag excessmore » should be measured. An independent photometric observation at the same wavelength reveals no excess. In addition, there exist published ISO observations of van Maanen 2 at 6.8 {micro}m and 15.0 {micro}m which are consistent with photospheric flux of a 6750 K white dwarf. If recent brown dwarf models are correct, there is no substellar companion with T{sub eff} {approx}> 500 K.« less

The Forced van der Pol Equation

ERIC Educational Resources Information Center

Fay, Temple H.

2009-01-01

We report on a study of the forced van der Pol equation x + [epsilon](x[superscript 2] - 1)x + x = F cos[omega]t, by solving numerically the differential equation for a variety of values of the parameters [epsilon], F and [omega]. In doing so, many striking and interesting trajectories can be discovered and phenomena such as frequency entrainment,…

Willem van de Wall: Organizer and Innovator in Music Education and Music Therapy.

ERIC Educational Resources Information Center

Clair, Alicia Ann; Heller, George N.

1989-01-01

Examines Willem van de Wall's historically significant contributions to seminal literature on music therapy and the influence of music on behavior. Reviews van de Wall's early writings, at his work on music for children, and on music in institutions. Cites his "Music in Hospitals" as the culmination of his work in music therapy, music…

Assurance of neuroattenuation of a live vaccine against West Nile virus: A comprehensive study of neuropathogenesis after infection with chimeric WN/DEN4Δ30 vaccine in comparison to two parental viruses and a surrogate flavivirus reference vaccine

PubMed Central

Maximova, Olga A.; Speicher, James M.; Skinner, Jeff R.; Murphy, Brian R.; St Claire, Marisa C.; Ragland, Danny R.; Herbert, Richard L.; Pare, Dan R.; Moore, Rashida M.; Pletnev, Alexander G.

2014-01-01

The upsurge of West Nile virus (WNV) human infections in 2012 suggests that the US can expect periodic WNV outbreaks in the future. Availability of safe and effective vaccines against WNV in endemic areas, particularly for aging populations that are at high risk of West Nile neuroinvasive disease (WNND), could be beneficial. WN/DEN4Δ30 is a live, attenuated chimeric vaccine against WNV produced by replacement of the genes encoding the pre-membrane and envelope protein genes of the vaccine virus against dengue virus type 4 (DEN4Δ30) with corresponding sequences derived from a wild type WNV. Following intrathalamic inoculation of nonhuman primates (NHPs), a comprehensive neuropathogenesis study was performed and neurovirulence of WN/DEN4Δ30 vaccine candidate was compared to that of two parental viruses (i.e., WNV and DEN4Δ30), as well as to that of an attenuated flavivirus surrogate reference (i.e., yellow fever YF 17D). Clinical and virological data, as well as results of a semi-quantitative histopathological analysis, demonstrated that WN/DEN4Δ30 vaccine is highly attenuated for the central nervous system (CNS) of NHPs in comparison to a wild type WNV. Importantly, based on the virus replicative ability in the CNS of NHPs and the degree of induced histopathological changes, the level of neuroattenuation of WN/DEN4Δ30 vaccine was similar to that of YF 17D, and therefore within an acceptable range. In addition, we show that the DEN4Δ30 vaccine tested in this study also has a low neurovirulence profile. In summary, our results demonstrate a high level of neuroattenuation of two vaccine candidates, WN/DEN4Δ30 and DEN4Δ30. We also show here a remarkable sensitivity of our WNV-NY99 NHP model, as well as striking resemblance of the observed neuropathology to that seen in human WNND. These results support the use of this NHP model for translational studies of WNV neuropathogenesis and/or testing the effectiveness of vaccines and therapeutic approaches. PMID

Pheromonally mediated sexual isolation among denning populations of red-sided garter snakes, Thamnophis sirtalis parietalis.

PubMed

Lemaster, Michael P; Mason, Robert T

2003-04-01

Utilizing behavioral experiments and chemical analyses, we examined whether pheromonally mediated sexual isolation exists between denning populations of red-sided garter snakes (Thamtnophis sirtalis parietalis) in Manitoba, Canada. Simultaneous choice tests conducted during the breeding season revealed that adult males from a hibernaculum in central Manitoba displayed a strong courtship preference for females from their own population over females from a hibernaculum in western Manitoba, whereas males from the western Manitoba hibernaculum showed no such preference. In addition. trailing experiments testing the response of males from the two hibernacula to familiar and unfamiliar female trails showed similar results, demonstrating that the observed male preference is mediated through chemical cues. Subsequent chemical analysis of the female sexual attractiveness pheromone. a homologous series of long-chain saturated and (omega-9 cis-unsaturated methyl ketones responsible for eliciting male courtship behavior and trailing behavior in garter snakes, showed significant variation in the composition of the pheromone between the two populations. Specifically, the two populations varied in the relative concentrations of individual unsaturated methyl ketones expressed by females. These results suggest that sexual isolation exists to a degree among denning populations of red-sided garter snakes due to variation in the expression of the female sexual attractiveness pheromone.

[Mobile hospital -real time mobile telehealthcare system with ultrasound and CT van using high-speed satellite communication-].

PubMed

Takizawa, Masaomi; Miyashita, Toyohisa; Murase, Sumio; Kanda, Hirohito; Karaki, Yoshiaki; Yagi, Kazuo; Ohue, Toru

2003-01-01

A real-time telescreening system is developed to detect early diseases for rural area residents using two types of mobile vans with a portable satellite station. The system consists of a satellite communication system with 1.5Mbps of the JCSAT-1B satellite, a spiral CT van, an ultrasound imaging van with two video conference system, a DICOM server and a multicast communication unit. The video image and examination image data are transmitted from the van to hospitals and the university simultaneously. Physician in the hospital observes and interprets exam images from the van and watches the video images of the position of ultrasound transducer on screenee in the van. After the observation images, physician explains a results of the examination by the video conference system. Seventy lung CT screening and 203 ultrasound screening were done from March to June 2002. The trial of this real time screening suggested that rural residents are given better healthcare without visit to the hospital. And it will open the gateway to reduce the medical cost and medical divide between city area and rural area.

Design of a command, communications, and control van (surrogate)

NASA Astrophysics Data System (ADS)

Holder, J. Darryl; Fishback, Jerome

1989-03-01

This report describes the design, construction, and checkout of a radio and telephone multi-mode communications hub. This unit is to serve as a surrogate for a command, control, and communications van which is to be used in support of a special series of testing at a remote site. This unit is assembled in a military four-wheel van and has a crew of a commander and three operators. Radio communications monitoring can be performed in all popular modes of transmission from 50 KHz to 2 GHz and transmission can be performed on selected frequencies in the 40-meter, 6-meter, and 2-meter bands. Both voice and digital (teletype, packet, facsimile, etc.) communications are supported.

Testing the dynamic rollover resistance of two 15-passenger vans with multiple load configurations

DOT National Transportation Integrated Search

2004-06-01

As a consequence of NTSB Safety Recommendations H-02-26 and H-02-28, NHTSA performed a study to investigate the effects different load conditions may have on the dynamic rollover resistance of 15-passenger vans. The two vans used in this study, a 200...

A New Method for Suppressing Periodic Narrowband Interference Based on the Chaotic van der Pol Oscillator

NASA Astrophysics Data System (ADS)

Lu, Jia; Zhang, Xiaoxing; Xiong, Hao

The chaotic van der Pol oscillator is a powerful tool for detecting defects in electric systems by using online partial discharge (PD) monitoring. This paper focuses on realizing weak PD signal detection in the strong periodic narrowband interference by using high sensitivity to the periodic narrowband interference signals and immunity to white noise and PD signals of chaotic systems. A new approach to removing the periodic narrowband interference by using a van der Pol chaotic oscillator is described by analyzing the motion characteristic of the chaotic oscillator on the basis of the van der Pol equation. Furthermore, the Floquet index for measuring the amplitude of periodic narrowband signals is redefined. The denoising signal processed by the chaotic van der Pol oscillators is further processed by wavelet analysis. Finally, the denoising results verify that the periodic narrowband and white noise interference can be removed efficiently by combining the theory of the chaotic van der Pol oscillator and wavelet analysis.

Dietary plasticity in a nutrient-rich system does not influence brown bear (Ursus arctos) body condition or denning

USGS Publications Warehouse

Mangipane, Lindsey S.; Belant, Jerrold L.; Lafferty, Diana J. R.; Gustine, David D.; Hiller, Tim L.; Colvin, Michael E.; Mangipane, Buck A.; Hilderbrand, Grant V.

2018-01-01

Behavioral differences within a population can allow use of a greater range of resources among individuals. The brown bear (Ursus arctos) is a generalist omnivore that occupies diverse habitats and displays considerable plasticity in food use. We evaluated whether brown bear foraging that resulted in deviations from a proposed optimal diet influenced body condition and, in turn, denning duration in Lake Clark National Park and Preserve, Alaska. To assess assimilated diet, we used sectioned guard hair samples (n = 23) collected in autumn to determine stable carbon and nitrogen isotope ratios. To index proportional contributions of meat and vegetation to assimilated diets, we compared the carbon (δ13C) and nitrogen (δ15N) values of hair samples with the values identified for major food categories. We then compared percentage body fat and body mass in relation to the proportion of assimilated meat in the diet using linear models. We also examined the influence of autumn percentage body fat and mass on denning duration. Percentage body fat was not influenced by the proportion of assimilated meat in the diet. Additionally, percentage body fat and body mass did not influence denning duration. However, body mass of bears assimilating proportionately more meat was greater than bears assimilating less meat. Our results provide support for previous findings that larger bears consume higher amounts of protein to maintain their body size and therefore forage further from the proposed optimal diet. Additionally, our results demonstrate that individuals can achieve similar biological outcomes (e.g., percentage body fat) despite variable foraging strategies, suggesting that individuals within generalist populations may confer an adaptive advantage through behavioral plasticity.

Bernard van Leer Foundation Annual Report, 2001.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This annual report for 2001 describes the year's activities, achievements, and financial status of the Bernard van Leer Foundation, a private foundation based in The Netherlands operating internationally to improve opportunities for young children from birth to age 7 living in circumstances of social and economic disadvantage. Following the…

Bernard van Leer Foundation Annual Report, 2002.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This annual report for 2002 describes the year's activities, achievements, and financial status of the Bernard van Leer Foundation, a private foundation based in The Netherlands operating internationally to improve opportunities for young children from birth to age 7 living in circumstances of social and economic disadvantage. Following the…

Recent Science Highlights of the Van Allen Probes Mission

NASA Astrophysics Data System (ADS)

Ukhorskiy, Aleksandr

2016-10-01

The morning of 30 August 2012 saw an Atlas 5 rocket launch NASA's second Living With a Star spacecraft mission, the twin Radiation Belt Storm Probes, into an elliptic orbit cutting through Earth's radiation belts. Renamed the Van Allen Probes soon after launch, the Probes are designed to determine how the highly variable populations of high-energy charged particles within the radiation belts, dangerous to astronauts and satellites, are created, respond to solar variations, and evolve in space environments. The Van Allen Probes mission extends beyond the practical considerations of the hazard's of Earth's space environment. Twentieth century observations of space and astrophysical systems throughout the solar system and out into the observable universe have shown that the processes that generate intense particle radiation within magnetized environments such as Earth's are universal. During its mission the Van Allen Probes verified and quantified previously suggested energization processes, discovered new energization mechanisms, revealed the critical importance of dynamic plasma injections into the innermost magnetosphere, and used uniquely capable instruments to reveal inner radiation belt features that were all but invisible to previous sensors. This paper gives a brief overview of the mission, presents some recent science highlights, and discusses plans for the extended mission.

Dike Strength Analysis on a Regional Scale Based On a Stochastic Subsoil Model

NASA Astrophysics Data System (ADS)

Koelewijn, A. R.; Vastenburg, E. W.

2013-12-01

About two-third of the Netherlands is protected against flooding by dikes and levees. The subsoil can be characterized by fluvial and marine sediments. Maintaining the safety of these dikes and levees is of vital importance. Insufficient safety is not permissible, but excessive safety would imply a waste of money and other resources. Therefore safety assessments are carried out on a regular basis. Over the past decades, a practice has grown to calculate a limited number of cross-sections, roughly one every 500 to 1000 meters. For this purpose, a representative cross-section is selected as an estimate of the most vulnerable surface geometry and the subsoil conditions determined from boreholes and cone penetration tests, for which slope stability and piping analyses are carried out. This is a time-consuming procedure which is not only expensive, but also neglects geological knowledge. A method to incorporate geological knowledge of an area, including updating on the basis of additional investigations, has been described in Koelewijn et al. [2011]. In addition, various groups have worked to incorporate geotechnical stability models and detailed Lidar-measurements of the surface into a more efficient and rational calculation process [Knoeff et al. 2011, Lam et al. 2013, van den Ham & Mastbergen, 2013]. Combining this experience with the 3D subsoil model opens possibilities for cost-effective additional soil investigations for those locations where ruling out unfavorable conditions really influences the decisions to be made regarding rejection and improvement, see the figure for examples of different subsoil profiles along a dike. The resulting system has been applied for semi-automated calculations of dikes in various parts of the Netherlands, totalling over 4000 km by now, and a part of the Mississippi levee system. [van den Ham & Mastbergen, 2013] G.A. van den Ham & D.R. Mastbergen, A semi-probabilistic assessment method for flow slides. AGU Fall meeting, 2013

Research and the Bernard van Leer Foundation.

ERIC Educational Resources Information Center

Wall, W. D.

1978-01-01

Outlines Bernard van Leer Foundation sponsorship of action programs and research studies of child development in 25 countries. The problems and possibilities of such work are discussed from the viewpoint of evaluation and the contribution which can be made to the behavioral sciences--notably to comparative child development. (Author/RH)

Bernard van Leer Foundation Annual Report, 1999.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This annual report details the activities and financial status for 1999 of the Bernard van Leer Foundation, a private institution created in 1949 for broad humanitarian purposes. Following the introduction by the chairman of the Foundation's board of trustees, the report of the executive director details activities during the Foundation's fiftieth…

Bernard van Leer Foundation Annual Report, 2000.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This annual report for 2000 describes the year's activities, achievements, and financial status of the Bernard van Leer Foundation, a private foundation based in The Netherlands that operates internationally to improve opportunities for young children from birth to age 7 living in circumstances of social and economic disadvantage. Following an…

Overview of the critical disaster management challenges faced during Van 2011 earthquakes.

PubMed

Tolon, Mert; Yazgan, Ufuk; Ural, Derin N; Goss, Kay C

2014-01-01

On October 23, 2011, a M7.2 earthquake caused damage in a widespread area in the Van province located in eastern Turkey. This strong earthquake was followed by a M5.7 earthquake on November 9, 2011. This sequence of damaging earthquakes led to 644 fatalities. The management during and after these earthquake disaster imposed many critical challenges. In this article, an overview of these challenges is presented based on the observations by the authors in the aftermath of this disaster. This article presents the characteristics of 2011 Van earthquakes. Afterward, the key information related to the four main phases (ie, preparedness, mitigation, response, and recovery) of the disaster in Van is presented. The potential strategies that can be taken to improve the disaster management practice are identified, and a set of recommendations are proposed to improve the existing situation.

Injury biomechanics of C2 dens fractures.

PubMed

Yoganandan, Narayan; Pintar, Frank; Baisden, Jamie; Gennarelli, Thomas; Maiman, Dennis

2004-01-01

The objective of this study is to analyze the biomechanics of dens fractures of the second cervical vertebra in the adult population due to motor vehicle crashes. Case-by-case records from the Crash Injury Research and Engineering Network (CIREN) and National Automotive Sampling System (NASS) databases were used. Variables such as change in velocity, impact direction and body habitus were extracted. Results indicated that similarities exist in the two databases despite differences in sampling methods between the two sources (e.g., CIREN is not population based). Trauma is predominantly associated with the frontal mode of impact. Majority of injuries occur with change in velocities below current federal guideline thresholds. No specific bias exists with respect to variables such as age, height, weight, and gender. Because similar conclusions can be drawn with regard to vehicle model years, design changes during these years may have had little effect on this injury. To ameliorate trauma, emphasis should be placed on the frontal impact mode and entire adult population. Because of clinical implications in the fracture type (II being most critical) and lack of specific coding, CIREN data demonstrates the need to improve injury coding in the AIS and application in the NASS to enhance occupant safety and treatment in the field of automotive medicine.

Conversion of Chemical Reaction Energy into Useful Work in the Van't Hoff Equilibrium Box

ERIC Educational Resources Information Center

Bazhin, N. M.; Parmon, V. N.

2007-01-01

The ideal van't Hoff equilibrium box is described in detail. It shows that van't Hoff equilibrium box divided in two parts can simultaneously produce heat and useful work without violation of the first law of thermodynamics.

Heath Van Essen - Clean Water Act Public Notice

EPA Pesticide Factsheets

The EPA is providing notice of a proposed Administrative Penalty Assessment against Heath Van Essen, Respondent, an individual who owns or operates an animal feeding operation (“Facility”) that is located in Section 27 of Township 98 North, Range 47 West,

Confirming the appearance of excess success: Reply to van Boxtel and Koch (2016).

PubMed

Francis, Gregory

2016-12-01

van Boxtel and Koch (Psychonomic Bulletin & Review. doi: 10.3758/s13423-016-1010-0 , 2016) reported finding problems in the Test for Excess Success (TES) analysis in Francis (Psychonomic Bulletin & Review, 21, 1180-1187, 2014). They argued that their findings undermined the general analysis and the conclusions of the specific TES analysis for their article (van Boxtel & Koch in Psychological Science, 23(4), 410-418, 2012). As shown in this paper, their reported problems reflect misunderstandings about both the general properties of a TES analysis and how it was applied to their specific set of findings. Another look at the findings and theoretical claims in van Boxtel and Koch (Psychological Science, 23(4), 410-418, 2012) confirms the appearance of excess success.

Comparison of three PCR primer sets for identification of vanB gene carriage in feces and correlation with carriage of vancomycin-resistant enterococci: interference by vanB-containing anaerobic bacilli.

PubMed

Ballard, S A; Grabsch, E A; Johnson, P D R; Grayson, M L

2005-01-01

We assessed the sensitivities and specificities of three previously described PCR primers on enrichment broth cultures of feces for the accurate detection of fecal carriage of vancomycin-resistant enterococci (VRE). In addition, we investigated specimens that were vanB PCR positive but VRE culture negative for the presence of other vanB-containing pathogens. Feces from 59 patients (12 patients carrying vanB Enterococcus faecium strains and 47 patients negative for VRE carriage) were cultured for 36 h in aerobic brain heart infusion (BHI) broth, anaerobic BHI (AnO(2)BHI) broth, or aerobic Enterococcosel (EC) broth. DNA was extracted from the cultures and tested for the presence of vanB by using the PCR primers of Dutka-Malen et al. (S. Dutka-Malen, S. Evers, and P. Courvalin, J. Clin. Microbiol. 33:24-27, 1995), Bell et al. (J. M. Bell, J. C. Paton, and J. Turnidge, J. Clin. Microbiol. 36:2187-2190, 1998), and Stinear et al. (T. P. Stinear, D. C. Olden, P. D. R. Johnson, J. K. Davies, and M. L. Grayson, Lancet 357:855-856, 2001). The sensitivity (specificity) of PCR compared with the results of culture on BHI, AnO(2)BHI, and EC broths were 67% (96%), 50% (94%), and 17% (100%), respectively, with the primers of Dutka-Malen et al.; 92% (60%), 92% (45%), and 92% (83%), respectively, with the primers of Bell et al.; and 92% (49%), 92% (43%), and 100% (51%) respectively, with the primers of Stinear et al. The primers of both Bell et al. and Stinear et al. were significantly more sensitive than those of Dutka-Malen et al. in EC broth (P = 0.001 and P < 0.001, respectively). The poor specificities for all primer pairs were due in part to the isolation and identification of six anaerobic gram-positive bacilli, Clostridium hathewayi (n = 3), a Clostridium innocuum-like organism (n = 1), Clostridium bolteae (n = 1), and Ruminococcus lactaris-like (n = 1), from five fecal specimens that were vanB positive but VRE culture negative. All six organisms were demonstrated to contain

Bernard van Leer Foundation Annual Report 1998.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This document provides an annual report and financial review for 1998 of the Bernard van Leer Foundation, a private institution created in 1949 for broad humanitarian purposes. Following an introduction by chairman of the Foundation's board of trustees, a report of the executive director details the second year of implementation of the…

Van der Waals forces in pNRQED

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shtabovenko, Vladyslav

2016-01-22

We report on the calculation of electromagnetic van der Waals forces [1] between two hydrogen atoms using non-relativistic effective field theories (EFTs) of QED for large and small momentum transfers with respect to the intrinsic energy scale of the hydrogen atom. Our results reproduce the well known London and Casimir-Polder forces.

Dynamical importance of van der Waals saddle and excited potential surface in C(1D)+D2 complex-forming reaction

PubMed Central

Shen, Zhitao; Ma, Haitao; Zhang, Chunfang; Fu, Mingkai; Wu, Yanan; Bian, Wensheng; Cao, Jianwei

2017-01-01

Encouraged by recent advances in revealing significant effects of van der Waals wells on reaction dynamics, many people assume that van der Waals wells are inevitable in chemical reactions. Here we find that the weak long-range forces cause van der Waals saddles in the prototypical C(1D)+D2 complex-forming reaction that have very different dynamical effects from van der Waals wells at low collision energies. Accurate quantum dynamics calculations on our highly accurate ab initio potential energy surfaces with van der Waals saddles yield cross-sections in close agreement with crossed-beam experiments, whereas the same calculations on an earlier surface with van der Waals wells produce much smaller cross-sections at low energies. Further trajectory calculations reveal that the van der Waals saddle leads to a torsion then sideways insertion reaction mechanism, whereas the well suppresses reactivity. Quantum diffraction oscillations and sharp resonances are also predicted based on our ground- and excited-state potential energy surfaces. PMID:28094253

Van Allen Probes Science Gateway and Space Weather Data Processing

NASA Astrophysics Data System (ADS)

Romeo, G.; Barnes, R. J.; Weiss, M.; Fox, N. J.; Mauk, B.; Potter, M.; Kessel, R.

2014-12-01

The Van Allen Probes Science Gateway acts as a centralized interface to the instrument Science Operation Centers (SOCs), provides mission planning tools, and hosts a number of science related activities such as the mission bibliography. Most importantly, the Gateway acts as the primary site for processing and delivering the VAP Space Weather data to users. Over the past year, the web-site has been completely redesigned with the focus on easier navigation and improvements of the existing tools such as the orbit plotter, position calculator and magnetic footprint tool. In addition, a new data plotting facility has been added. Based on HTML5, which allows users to interactively plot Van Allen Probes summary and space weather data. The user can tailor the tool to display exactly the plot they wish to see and then share this with other users via either a URL or by QR code. Various types of plots can be created, including simple time series, data plotted as a function of orbital location, and time versus L-Shell. We discuss the new Van Allen Probes Science Gateway and the Space Weather Data Pipeline.

Determining Core Plasmaspheric Electron Densities with the Van Allen Probes

NASA Astrophysics Data System (ADS)

De Pascuale, S.; Hartley, D.; Kurth, W. S.; Kletzing, C.; Thaller, S. A.; Wygant, J. R.

2016-12-01

We survey three methods for obtaining electron densities inside of the core plasmasphere region (L < 4) to the perigee of the Van Allen Probes (L 1.1) from September 2012 to December 2014. Using the EMFISIS instrument on board the Van Allen Probes, electron densities are extracted from the upper hybrid resonance to an uncertainty of 10%. Some measurements are subject to larger errors given interpretational issues, especially at low densities (L > 4) resulting from geomagnetic activity. At high densities EMFISIS is restricted by an upper observable limit near 3000 cm-3. As this limit is encountered above perigee, we employ two additional methods validated against EMFISIS measurements to determine electron densities deep within the plasmasphere (L < 2). EMFISIS can extrapolate density estimates to lower L by calculating high densities, in good agreement with the upper hybrid technique when applicable, from plasma wave properties. Calibrated measurements, from the Van Allen Probes EFW potential instrument, also extend into this range. In comparison with the published EMFISIS database we provide a metric for the validity of core plasmaspheric density measurements obtained from these methods and an empirical density model for use in wave and particle simulations.

Geochemical survey of the Devil's Den Roadless Area, Rutland and Windsor counties, Vermont

USGS Publications Warehouse

Slack, J.F.; Atelsek, P.J.; Grosz, A.E.

1985-01-01

The Devils Den area is named for a large undercut cliff (Dale, 1915, p. 21) developed in Precambrian basement rocks. This undercut cliff forms a broad natural cave immediately west of and below Forest Service Road 10, at the head of Mt. Tabor Brook. Another much smaller cave is present in dolomite of probable Paleozoic (Early Cambrian) age on the east side of the same road. This smaller cave apparently is of artificial origin, having been made during early mining of the dolomite (Dale, 1915, p. 21). This man-made cave is the only evidence of previous mining activity within the study area.

Near-Unity Absorption in van der Waals Semiconductors for Ultrathin Optoelectronics.

PubMed

Jariwala, Deep; Davoyan, Artur R; Tagliabue, Giulia; Sherrott, Michelle C; Wong, Joeson; Atwater, Harry A

2016-09-14

We demonstrate near-unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (<15 nm) van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We further fabricate Schottky junction devices using these highly absorbing heterostructures and characterize their optoelectronic performance. Our work addresses one of the key criteria to enable TMDCs as potential candidates to achieve high optoelectronic efficiency.

Simulated Van Allen Belts Generated by Plasma Thruster in Tank 5

NASA Image and Video Library

1966-09-21

The model of the Earth housed inside Vacuum Tank 5 contained a coil which produced a magnetic field simulating that of the Earth. It was bombarded with a stream of ionized particles simulating the solar wind which impinges on the Earth's magnetic field. The bands or belts of luminous plasma seen in this image were suggestive of the Van Allen belts found around the Earth. Scientists at Lewis probed the plasma around the model and studied scaling laws in an attempt to find an explanation for the actual formation of the Van Allen belt.

78 FR 47817 - Parts and Accessories Necessary for Safe Operation; Application for an Exemption From Van Hool N...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-06

....V. and Coach USA AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT. ACTION: Notice of... exemption from Van Hool N.V. and Coach USA (Van Hool/Coach USA) to allow the use of double deck motorcoaches..., Van Hool/Coach USA is requesting an exemption that would allow the use of sleeper berths that comply...

When Diversity Training Isn’t Enough: The Case for Inclusive Leadership

DTIC Science & Technology

2012-07-24

When Diversity Training Isn’t Enough: The Case for Inclusive Leadership DEFENSE EQUAL OPPORTUNITY MANAGEMENT INSTITUTE...The Case for Inclusive Leadership Scientists predict that diversity in the workplace will increase substantially in the next century, including an...are applied consistently over time and people (van den Bos, Vermunt, & Wilke, 1996), if they are applied accurately (De Cremer , 2004), and when they

Say goodbye to coffee stains

NASA Astrophysics Data System (ADS)

Burak Eral, H.; van den Ende, Dirk; Mugele, Frieder

2012-04-01

Discussing ideas over a mug of coffee or tea is the lifeblood of science, but have you ever thought about the stains that can be inadvertently left behind? H Burak Eral, Dirk van den Ende and Frieder Mugele explain how these stains, which can be a major annoyance in some biology techniques, can be altered for the better using a technique called electrowetting.

Assurance of neuroattenuation of a live vaccine against West Nile virus: a comprehensive study of neuropathogenesis after infection with chimeric WN/DEN4Δ30 vaccine in comparison to two parental viruses and a surrogate flavivirus reference vaccine.

PubMed

Maximova, Olga A; Speicher, James M; Skinner, Jeff R; Murphy, Brian R; St Claire, Marisa C; Ragland, Danny R; Herbert, Richard L; Pare, Dan R; Moore, Rashida M; Pletnev, Alexander G

2014-05-30

The upsurge of West Nile virus (WNV) human infections in 2012 suggests that the US can expect periodic WNV outbreaks in the future. Availability of safe and effective vaccines against WNV in endemic areas, particularly for aging populations that are at high risk of West Nile neuroinvasive disease (WNND), could be beneficial. WN/DEN4Δ30 is a live, attenuated chimeric vaccine against WNV produced by replacement of the genes encoding the pre-membrane and envelope protein genes of the vaccine virus against dengue virus type 4 (DEN4Δ30) with corresponding sequences derived from a wild type WNV. Following intrathalamic inoculation of nonhuman primates (NHPs), a comprehensive neuropathogenesis study was performed and neurovirulence of WN/DEN4Δ30 vaccine candidate was compared to that of two parental viruses (i.e., WNV and DEN4Δ30), as well as to that of an attenuated flavivirus surrogate reference (i.e., yellow fever YF 17D). Clinical and virological data, as well as results of a semi-quantitative histopathological analysis, demonstrated that WN/DEN4Δ30 vaccine is highly attenuated for the central nervous system (CNS) of NHPs in comparison to a wild type WNV. Importantly, based on the virus replicative ability in the CNS of NHPs and the degree of induced histopathological changes, the level of neuroattenuation of WN/DEN4Δ30 vaccine was similar to that of YF 17D, and therefore within an acceptable range. In addition, we show that the DEN4Δ30 vaccine tested in this study also has a low neurovirulence profile. In summary, our results demonstrate a high level of neuroattenuation of two vaccine candidates, WN/DEN4Δ30 and DEN4Δ30. We also show here a remarkable sensitivity of our WNV-NY99 NHP model, as well as striking resemblance of the observed neuropathology to that seen in human WNND. These results support the use of this NHP model for translational studies of WNV neuropathogenesis and/or testing the effectiveness of vaccines and therapeutic approaches. Published

Bernard van Leer Foundation. Annual Report 1997.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This document provides an annual report and financial review of the Bernard van Leer Foundation, a private institution created in 1949 for broad humanitarian purposes. Following an introduction by the chairman of the Foundation's board of trustees, a report of the executive director details the first full-year of implementation of the Foundation's…

Bernard van Leer Foundation Annual Report 1996.

ERIC Educational Resources Information Center

Bernard Van Leer Foundation, The Hague (Netherlands).

This document provides an annual report and financial review for 1996 of the Bernard van Leer Foundation, a private institution created in 1949 for broad humanitarian purposes. Following a summary by the executive director of the Foundation, the report includes a description of the foundation and its grants. It then lists, by country, the major…

A notable difference between ideal gas and infinite molar volume limit of van der Waals gas

NASA Astrophysics Data System (ADS)

Liu, Q. H.; Shen, Y.; Bai, R. L.; Wang, X.

2010-05-01

The van der Waals equation of state does not sufficiently represent a gas unless a thermodynamic potential with two proper and independent variables is simultaneously determined. The limiting procedures under which the behaviour of the van der Waals gas approaches that of an ideal gas are letting two van der Waals coefficients be zero rather than letting the molar volume become infinitely large; otherwise, the partial derivative of internal energy with respect to pressure at a fixed temperature does not vanish.

Self-Aligned van der Waals Heterojunction Diodes and Transistors.

PubMed

Sangwan, Vinod K; Beck, Megan E; Henning, Alex; Luo, Jiajia; Bergeron, Hadallia; Kang, Junmo; Balla, Itamar; Inbar, Hadass; Lauhon, Lincoln J; Hersam, Mark C

2018-02-14

A general self-aligned fabrication scheme is reported here for a diverse class of electronic devices based on van der Waals materials and heterojunctions. In particular, self-alignment enables the fabrication of source-gated transistors in monolayer MoS 2 with near-ideal current saturation characteristics and channel lengths down to 135 nm. Furthermore, self-alignment of van der Waals p-n heterojunction diodes achieves complete electrostatic control of both the p-type and n-type constituent semiconductors in a dual-gated geometry, resulting in gate-tunable mean and variance of antiambipolar Gaussian characteristics. Through finite-element device simulations, the operating principles of source-gated transistors and dual-gated antiambipolar devices are elucidated, thus providing design rules for additional devices that employ self-aligned geometries. For example, the versatility of this scheme is demonstrated via contact-doped MoS 2 homojunction diodes and mixed-dimensional heterojunctions based on organic semiconductors. The scalability of this approach is also shown by fabricating self-aligned short-channel transistors with subdiffraction channel lengths in the range of 150-800 nm using photolithography on large-area MoS 2 films grown by chemical vapor deposition. Overall, this self-aligned fabrication method represents an important step toward the scalable integration of van der Waals heterojunction devices into more sophisticated circuits and systems.

Molecular Characterization of Enterococcus faecalis N06-0364 with Low-Level Vancomycin Resistance Harboring a Novel d-Ala-d-Ser Gene Cluster, vanL▿

PubMed Central

Boyd, David A.; Willey, Barbara M.; Fawcett, Darlene; Gillani, Nazira; Mulvey, Michael R.

2008-01-01

Enterococcus faecalis N06-0364, exhibiting a vancomycin MIC of 8 μg/ml, was found to harbor a novel d-Ala-d-Ser gene cluster, designated vanL. The vanL gene cluster was similar in organization to the vanC operon, but the VanT serine racemase was encoded by two separate genes, vanTmL (membrane binding) and vanTrL (racemase). PMID:18458129

Isotope engineering of van der Waals interactions in hexagonal boron nitride

NASA Astrophysics Data System (ADS)

Vuong, T. Q. P.; Liu, S.; van der Lee, A.; Cuscó, R.; Artús, L.; Michel, T.; Valvin, P.; Edgar, J. H.; Cassabois, G.; Gil, B.

2018-02-01

Hexagonal boron nitride is a model lamellar compound where weak, non-local van der Waals interactions ensure the vertical stacking of two-dimensional honeycomb lattices made of strongly bound boron and nitrogen atoms. We study the isotope engineering of lamellar compounds by synthesizing hexagonal boron nitride crystals with nearly pure boron isotopes (10B and 11B) compared to those with the natural distribution of boron (20 at% 10B and 80 at% 11B). On the one hand, as with standard semiconductors, both the phonon energy and electronic bandgap varied with the boron isotope mass, the latter due to the quantum effect of zero-point renormalization. On the other hand, temperature-dependent experiments focusing on the shear and breathing motions of adjacent layers revealed the specificity of isotope engineering in a layered material, with a modification of the van der Waals interactions upon isotope purification. The electron density distribution is more diffuse between adjacent layers in 10BN than in 11BN crystals. Our results open perspectives in understanding and controlling van der Waals bonding in layered materials.

Isotope engineering of van der Waals interactions in hexagonal boron nitride.

PubMed

Vuong, T Q P; Liu, S; Van der Lee, A; Cuscó, R; Artús, L; Michel, T; Valvin, P; Edgar, J H; Cassabois, G; Gil, B

2018-02-01

Hexagonal boron nitride is a model lamellar compound where weak, non-local van der Waals interactions ensure the vertical stacking of two-dimensional honeycomb lattices made of strongly bound boron and nitrogen atoms. We study the isotope engineering of lamellar compounds by synthesizing hexagonal boron nitride crystals with nearly pure boron isotopes ( 10 B and 11 B) compared to those with the natural distribution of boron (20 at% 10 B and 80 at% 11 B). On the one hand, as with standard semiconductors, both the phonon energy and electronic bandgap varied with the boron isotope mass, the latter due to the quantum effect of zero-point renormalization. On the other hand, temperature-dependent experiments focusing on the shear and breathing motions of adjacent layers revealed the specificity of isotope engineering in a layered material, with a modification of the van der Waals interactions upon isotope purification. The electron density distribution is more diffuse between adjacent layers in 10 BN than in 11 BN crystals. Our results open perspectives in understanding and controlling van der Waals bonding in layered materials.

Inflationary universe in terms of a van der Waals viscous fluid

NASA Astrophysics Data System (ADS)

Brevik, I.; Elizalde, E.; Odintsov, S. D.; Timoshkin, A. V.

The inflationary expansion of our early-time universe is considered in terms of the van der Waals equation, as equation of state for the cosmic fluid, where a bulk viscosity contribution is assumed to be present. The corresponding gravitational equations for the energy density in a homogeneous and isotropic Friedmann-Lemaître-Robertson-Walker universe are solved, and an analytic expression for the scale factor is obtained. Attention is paid, specifically, to the role of the viscosity term in the accelerated expansion; the values of the slow-roll parameters, the spectral index, and the tensor-to-scalar ratio for the van der Waals model are calculated and compared with the most recent astronomical data from the Planck satellite. By imposing reasonable restrictions on the parameters of the van der Waals equation, in the presence of viscosity, it is shown to be possible for this model to comply quite precisely with the observational data. One can therefore conclude that the inclusion of viscosity in the theory of the inflationary epoch may definitely improve the cosmological models.

Automated Identification and Shape Analysis of Chorus Elements in the Van Allen Radiation Belts

NASA Astrophysics Data System (ADS)

Sen Gupta, Ananya; Kletzing, Craig; Howk, Robin; Kurth, William; Matheny, Morgan

2017-12-01

An important goal of the Van Allen Probes mission is to understand wave-particle interaction by chorus emissions in terrestrial Van Allen radiation belts. To test models, statistical characterization of chorus properties, such as amplitude variation and sweep rates, is an important scientific goal. The Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instrumentation suite provides measurements of wave electric and magnetic fields as well as DC magnetic fields for the Van Allen Probes mission. However, manual inspection across terabytes of EMFISIS data is not feasible and as such introduces human confirmation bias. We present signal processing techniques for automated identification, shape analysis, and sweep rate characterization of high-amplitude whistler-mode chorus elements in the Van Allen radiation belts. Specifically, we develop signal processing techniques based on the radon transform that disambiguate chorus elements with a dominant sweep rate against hiss-like chorus. We present representative results validating our techniques and also provide statistical characterization of detected chorus elements across a case study of a 6 s epoch.

Regenerative Endodontic Treatment with Orthodontic Treatment in a Tooth with Dens Evaginatus: A Case Report with a 4-year Follow-up.

PubMed

Natera, Marianella; Mukherjee, Padma M

2018-06-01

Dens evaginatus is a developmental tooth anomaly in which an extra cusp or tubercle protrudes on the occlusal surface of the tooth along with some pulpal tissue. Because of the fragile nature of the protrusion, these teeth are often at risk of pulpal exposure. When this occurs in an immature tooth, regenerative endodontic treatment may be a good treatment approach to promote root formation. There is limited literature that documents the occurrence of orthodontic treatment in teeth that have undergone regenerative endodontic therapy using triple antibiotic paste. Here we present a case of an immature premolar tooth with dens evaginatus that was diagnosed with pulp necrosis and chronic apical abscess. The tooth was treated with regenerative endodontic treatment; after which, the patient received orthodontic treatment with fixed appliances for 2 years. The tooth responded favorably to the regenerative endodontic treatment and orthodontic tooth movement. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth with evidence of periapical healing with stunted root development. The tooth remained asymptomatic even after 4 years. The regenerative endodontic procedure (REP) was successful in treating an immature permanent premolar with pulp necrosis and apical periodontitis with dens evaginatus. In this case, the tooth treated with an REP responded to orthodontic treatment similar to the nonendodontically treated teeth. Further studies are recommended to clarify the precise effects of orthodontic treatment on teeth treated with an REP. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Structuring of the Renewed Decision Making Process in the Royal Netherlands Army (Structurering van het vernieuwde besluitvormingsproces binnen de KL).

DTIC Science & Technology

1996-10-10

time informatie wordt door Eisenhardt (1989) gedefinieerd als " information about a firm’s operations or environment for which there is little or no...op het invoeren van (getypte) tekst . Conclusie Elektronisch Brainstormen: * in principe geschikt om Eigen Mogelijkheden te genereren, vooral als de...Capaieairt ca •acitenit ca a• C ie•lit Fig. 1 Mogelijke wijzen van besluitvorming (zie tekst ) als functie van beschik- bare tijd, capaciteit en ervaring van

Evaluatie Kennistechnologische Ondersteuning bij Diagnose van SEWACO systemen (Projectmanagementplan) (Evaluation of Knowledge Technological Support for Diagnosis of SEWACO Systems (Project Management Plan)

DTIC Science & Technology

1991-08-01

diagnos van SE WACO systmnen/ AD-A245 424111 1fl1,l Niets uit deze uitgave mag warden vermenigvuldligd en/of oPenbaar gemaakt door middel van druk...fotakopie. microfilm of op welks andere whlze dan ook, zonder voorafgaande toeslemming van TNO. Hot ter inzage geven van het TNO-rapport aan direct...belanghebbenden is tegestaan. HYP. vanl OC dt Indian dit rapport in opdracht ward uitgebracht, wordt voor de, rechten en verpiichtingen van opdrachtgever en

Phase-Defined van der Waals Schottky Junctions with Significantly Enhanced Thermoelectric Properties.

PubMed

Wang, Qiaoming; Yang, Liangliang; Zhou, Shengwen; Ye, Xianjun; Wang, Zhe; Zhu, Wenguang; McCluskey, Matthew D; Gu, Yi

2017-07-06

We demonstrate a van der Waals Schottky junction defined by crystalline phases of multilayer In 2 Se 3 . Besides ideal diode behaviors and the gate-tunable current rectification, the thermoelectric power is significantly enhanced in these junctions by more than three orders of magnitude compared with single-phase multilayer In 2 Se 3 , with the thermoelectric figure-of-merit approaching ∼1 at room temperature. Our results suggest that these significantly improved thermoelectric properties are not due to the 2D quantum confinement effects but instead are a consequence of the Schottky barrier at the junction interface, which leads to hot carrier transport and shifts the balance between thermally and field-driven currents. This "bulk" effect extends the advantages of van der Waals materials beyond the few-layer limit. Adopting such an approach of using energy barriers between van der Waals materials, where the interface states are minimal, is expected to enhance the thermoelectric performance in other 2D materials as well.

Van der Waals interaction mediated by an optically uniaxial layer

NASA Astrophysics Data System (ADS)

Šarlah, A.; Žumer, S.

2001-11-01

We study the van der Waals interaction between macroscopic bodies separated by a thin anisotropic film with a uniaxial permittivity tensor. We describe the effect of anisotropy of the media on the magnitude and sign of the interaction. The resulting differences in the van der Waals interaction are especially important for the stability of strongly confined liquid crystals, and nanostructures characterized by highly uniaxial macroscopic molecular arrangement, such as in self-assemblies of long organic molecules forming films, membranes, colloids, etc. We introduce an improved expression for the Hamaker constant which takes into account the uniaxial symmetry of a medium. In special cases neglecting the optical anisotropy even leads to an incorrect sign of the interaction.

Teaching Strategies of the van Dijk Curricular Approach.

ERIC Educational Resources Information Center

MacFarland, S. Z. C.

1995-01-01

This article presents 14 major teaching strategies for implementing the Jan van Dijk curricular approach with children who are deaf-blind. The theory underlying the approach is reported, and guidelines for implementing instructional strategies in the areas of communication, socialization, conceptualization, and movement are discussed. (Author/DB)

Vibration-rotation-tunneling spectroscopy of the van der Waals Bond: A new look at intermolecular forces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cohen, R.C.; Saykally, R.J.

Measurements of the low-frequency van der Waals vibrations in weakly bound complexes by high-resolution laser spectroscopy provide a means to probe intermolecular forces at unprecedented levels of detail and precision. Several new methods are presently being used to record vibration/rotation-tunneling (VRT) transitions associated with the motions of the weak bonds in van der Waals clusters. The most direct measurements are those probing only the van der Waals modes themselves, which occur at far-infrared wavelengths. This article presents a review of the information on both intramolecular forces and intramolecular dynamics that has been obtained from far-infrared VRT spectra of 18 complexesmore » during the past several years. Some rotationally resolved measurements of van der Waals modes observed in combination with electronic or vibrational excitation are also discussed. 185 refs., 15 figs., 1 tab.« less

A novel method for simultaneous Enterococcus species identification/typing and van genotyping by high resolution melt analysis.

PubMed

Gurtler, Volker; Grando, Danilla; Mayall, Barrie C; Wang, Jenny; Ghaly-Derias, Shahbano

2012-09-01

In order to develop a typing and identification method for van gene containing Enterococcus faecium, two multiplex PCR reactions were developed for use in HRM-PCR (High Resolution Melt-PCR): (i) vanA, vanB, vanC, vanC23 to detect van genes from different Enterococcus species; (ii) ISR (intergenic spacer region between the 16S and 23S rRNA genes) to detect all Enterococcus species and obtain species and isolate specific HRM curves. To test and validate the method three groups of isolates were tested: (i) 1672 Enterococcus species isolates from January 2009 to December 2009; (ii) 71 isolates previously identified and typed by PFGE (pulsed-field gel electrophoresis) and MLST (multi-locus sequence typing); and (iii) 18 of the isolates from (i) for which ISR sequencing was done. As well as successfully identifying 2 common genotypes by HRM from the Austin Hospital clinical isolates, this study analysed the sequences of all the vanB genes deposited in GenBank and developed a numerical classification scheme for the standardised naming of these vanB genotypes. The identification of Enterococcus faecalis from E. faecium was reliable and stable using ISR PCR. The typing of E. faecium by ISR PCR: (i) detected two variable peaks corresponding to different copy numbers of insertion sequences I and II corresponding to peak I and II respectively; (ii) produced 7 melt profiles for E. faecium with variable copy numbers of sequences I and II; (iii) demonstrated stability and instability of peak heights with equal frequency within the patient sample (36.4±4.5 days and 38.6±5.8 days respectively for 192 patients); (iv) detected ISR-HRM types with as much discrimination as PFGE and more than MLST; and (v) detected ISR-HRM types that differentiated some isolates that were identical by PFGE and MLST. In conjunction with the rapid and accurate van genotyping method described here, this ISR-HRM typing and identification method can be used as a stable identification and typing method with

Characterization and modelling of VanT: a novel, membrane-bound, serine racemase from vancomycin-resistant Enterococcus gallinarum BM4174.

PubMed

Arias, C A; Martín-Martinez, M; Blundell, T L; Arthur, M; Courvalin, P; Reynolds, P E

1999-03-01

Sequence determination of a region downstream from the vanXYc gene in Enterococcus gallinarum BM4174 revealed an open reading frame, designated vanT, that encodes a 698-amino-acid polypeptide with an amino-terminal domain containing 10 predicted transmembrane segments. The protein contained a highly conserved pyridoxal phosphate attachment site in the C-terminal domain, typical of alanine racemases. The protein was overexpressed in Escherichia coli, and serine racemase activity was detected in the membrane but not in the cytoplasmic fraction after centrifugation of sonicated cells, whereas alanine racemase activity was located almost exclusively in the cytoplasm. When the protein was overexpressed as a polypeptide lacking the predicted transmembrane domain, serine racemase activity was detected in the cytoplasm. The serine racemase activity was partially (64%) inhibited by D-cycloserine, whereas host alanine racemase activity was almost totally inhibited (97%). Serine racemase activity was also detected in membrane preparations of constitutively vancomycin-resistant E. gallinarum BM4174 but not in BM4175, in which insertional inactivation of the vanC-1 D-Ala:D-Ser ligase gene probably had a polar effect on expression of the vanXYc and vanT genes. Comparative modelling of the deduced C-terminal domain was based on the alignment of VanT with the Air alanine racemase from Bacillus stearothermophilus. The model revealed that almost all critical amino acids in the active site of Air were conserved in VanT, indicating that the C-terminal domain of VanT is likely to adopt a three-dimensional structure similar to that of Air and that the protein could exist as a dimer. These results indicate that the source of D-serine for peptidoglycan synthesis in vancomycin-resistant enterococci expressing the VanC phenotype involves racemization of L- to D-serine by a membrane-bound serine racemase.

Geometrothermodynamics of Van der Waals black hole

NASA Astrophysics Data System (ADS)

Hu, Yumin; Chen, Juhua; Wang, Yongjiu

2017-12-01

We study the geometrothermodynamics of a special asymptotically AdS black hole, i.e. Van der Waals ( VdW) black hole, in the extended phase space where the negative cosmological constant Λ can be regarded as thermodynamic pressure. Analysing some special conditions of this black hole with geometrothermodynamical method, we find a good correlation with ordinary cases according to the state equation.

Bio-Aerosol Testkamer: Ontwikkeling van Protocollen (Bio Aerosol Test Chamber: Development of Protocols)

DTIC Science & Technology

2007-07-01

testfaciliteit detector met de drie simulanten getest beschikbaar gekomen voor het testen van Beschrijving van de worden volgens gangbare internationale bio...2005 werd de Bio-Adrosol Testkamer (BAT-kamer) geplaatst door de firma Dycor Technologies Ltd., Canada. In de BAT-kamner kan een bio-ai5rosol...bestaande ruimte past. In beide gevallen bleek de firma Dycor Technologies Ltd in Canada (http://www.dycor.com) de beste leverancier te zijn, en voor beide

49 CFR 393.128 - What are the rules for securing automobiles, light trucks and vans?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false What are the rules for securing automobiles, light... automobiles, light trucks and vans? (a) Applicability. The rules in this section apply to the transportation of automobiles, light trucks, and vans which individually weigh 4,536 kg. (10,000 lb) or less...

49 CFR 393.128 - What are the rules for securing automobiles, light trucks and vans?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false What are the rules for securing automobiles, light... automobiles, light trucks and vans? (a) Applicability. The rules in this section apply to the transportation of automobiles, light trucks, and vans which individually weigh 4,536 kg. (10,000 lb) or less...

49 CFR 393.128 - What are the rules for securing automobiles, light trucks and vans?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false What are the rules for securing automobiles, light... automobiles, light trucks and vans? (a) Applicability. The rules in this section apply to the transportation of automobiles, light trucks, and vans which individually weigh 4,536 kg. (10,000 lb) or less...

49 CFR 393.128 - What are the rules for securing automobiles, light trucks and vans?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false What are the rules for securing automobiles, light... automobiles, light trucks and vans? (a) Applicability. The rules in this section apply to the transportation of automobiles, light trucks, and vans which individually weigh 4,536 kg. (10,000 lb) or less...

49 CFR 393.128 - What are the rules for securing automobiles, light trucks and vans?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false What are the rules for securing automobiles, light... automobiles, light trucks and vans? (a) Applicability. The rules in this section apply to the transportation of automobiles, light trucks, and vans which individually weigh 4,536 kg. (10,000 lb) or less...

46 CFR 194.10-15 - Magazine van construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Magazine van construction. 194.10-15 Section 194.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS HANDLING... system shall be of watertight construction and bear a label plate denoting the power requirement of the...

12 & 15 passenger vans tire pressure study : preliminary results

DOT National Transportation Integrated Search

2005-05-01

A study was conducted by the National Highway Traffic Safety Administration's (NHTSA's) National Center for Statistics and Analysis (NCSA) to determine the extent of underinflation and observe the tire condition in 12- and 15-passenger vans. This Res...

Dancing bunches as Van Kampen modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burov, A.; /Fermilab

2011-03-01

Van Kampen modes are eigen-modes of Jeans-Vlasov equation [1-3]. Their spectrum consists of continuous and, possibly, discrete parts. Onset of a discrete van Kampen mode means emergence of a coherent mode without any Landau damping; thus, even a tiny couple-bunch wake is sufficient to drive instability. Longitudinal instabilities observed at Tevatron [4], RHIC [5] and SPS [6] can be explained as loss of Landau damping (LLD), which is shown here to happen at fairly low impedances. For repulsive wakes and single-harmonic RF, LLD is found to be extremely sensitive to steepness of the bunch distribution function at small amplitudes. Basedmore » on that, a method of beam stabilization is suggested. Emergence of a discrete van Kampen mode means either loss of Landau damping or instability. Longitudinal bunch stability is analysed in weak head-tail approximation for inductive impedance and single-harmonic RF. The LLD threshold intensities are found to be rather low: for cases under study all of them do not exceed a few percent of the zero-amplitude incoherent synchrotron frequency shift, strongly decreasing for shorter bunches. Because of that, LLD can explain longitudinal instabilities happened at fairly low impedances at Tevatron [4], and possibly for RHIC [5] and SPS [6], being in that sense an alternative to the soliton explanation [5, 20]. Although LLD itself results in many cases in emergence of a mode with zero growth rate, any couple-bunch (and sometimes multi-turn) wake would drive instability for that mode, however small this wake is. LLD is similar to a loss of immune system of a living cell, when any microbe becomes fatal for it. The emerging discrete mode is normally very different from the rigid-bunch motion; thus the rigid-mode model significantly overestimates the LLD threshold. The power low of LLD predicted in Ref. [17] agrees with results of this paper. However, the numerical factor in that scaling low strongly depends on the bunch distribution

Spin-Flavor van der Waals Forces and NN interaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvaro Calle Cordon, Enrique Ruiz Arriola

A major goal in Nuclear Physics is the derivation of the Nucleon-Nucleon (NN) interaction from Quantum Chromodynamics (QCD). In QCD the fundamental degrees of freedom are colored quarks and gluons which are confined to form colorless strongly interacting hadrons. Because of this the resulting nuclear forces at sufficiently large distances correspond to spin-flavor excitations, very much like the dipole excitations generating the van der Waals (vdW) forces acting between atoms. We study the Nucleon-Nucleon interaction in the Born-Oppenheimer approximation at second order in perturbation theory including the Delta resonance as an intermediate state. The potential resembles strongly chiral potentials computedmore » either via soliton models or chiral perturbation theory and has a van der Waals like singularity at short distances which is handled by means of renormalization techniques. Results for the deuteron are discussed.« less

IVAN: Intelligent Van for the Distribution of Pharmaceutical Drugs

PubMed Central

Moreno, Asier; Angulo, Ignacio; Perallos, Asier; Landaluce, Hugo; Zuazola, Ignacio Julio García; Azpilicueta, Leire; Astrain, José Javier; Falcone, Francisco; Villadangos, Jesús

2012-01-01

This paper describes a telematic system based on an intelligent van which is capable of tracing pharmaceutical drugs over delivery routes from a warehouse to pharmacies, without altering carriers' daily conventional tasks. The intelligent van understands its environment, taking into account its location, the assets and the predefined delivery route; with the capability of reporting incidences to carriers in case of failure according to the established distribution plan. It is a non-intrusive solution which represents a successful experience of using smart environments and an optimized Radio Frequency Identification (RFID) embedded system in a viable way to resolve a real industrial need in the pharmaceutical industry. The combination of deterministic modeling of the indoor vehicle, the implementation of an ad-hoc radiating element and an agile software platform within an overall system architecture leads to a competitive, flexible and scalable solution. PMID:22778659

The Educational Thought of Cornelius Van Til: Philosophical Foundations of the Contemporary Christian School Movement.

ERIC Educational Resources Information Center

Maffet, Gregory J.; Dye, Charles M.

This paper gives an account of the thoughts of Cornelius Van Til on the contemporary Christian school movement. An account of the historical development of Christian compromise is given, followed by a critique of the compromise among contemporary Christian educators. Van Til claims that any educational position which falls short of being founded…

Unconscious Odour Conditioning 25 Years Later: Revisiting and Extending "Kirk-Smith, Van Toller and Dodd"

ERIC Educational Resources Information Center

Zucco, Gesualdo M.; Paolini, Michela; Schaal, Benoist

2009-01-01

The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). "Unconscious odour conditioning in human subjects." "Biological Psychology," 17, 221-231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is…

A high-pressure van der Waals compound in solid nitrogen-helium mixtures

NASA Technical Reports Server (NTRS)

Vos, W. L.; Finger, L. W.; Hemley, R. J.; Hu, J. Z.; Mao, H. K.; Schouten, J. A.

1992-01-01

A detailed diamond anvil-cell study using synchrotron X-ray diffraction, Raman scattering, and optical microscopy has been conducted for the He-N system, with a view to the weakly-bound van der Waals molecule interactions that can be formed in the gas phase. High pressure is found to stabilize the formation of a stoichiometric, solid van der Waals compound of He(N2)11 composition which may exemplify a novel class of compounds found at high pressures in the interiors of the outer planets and their satellites.

Nonlinear Hyperbolic Equations - Theory, Computation Methods, and Applications. Volume 24. Note on Numerical Fluid Mechanics

DTIC Science & Technology

1989-01-01

Calculations and Experiments (B.van den Berg/ D.A. Humphreysl E. Krause /J.P. F. Lindhout) Volume 20 Proceedings of the Seventh GAMM-Conference on...GRID METHODS FOR HYPERBOLIC PROBLEMS Wolfgang Hackbusch Sigrid Hagemann Institut fUr Informatik und Praktische Mathematik Christian-Albrechts...Euler Equations. Proceedings of the 8th Inter- national Conference on Numerical Methods in Fluid Dynamics (E. Krause , ed.), Aachen, 1988. Springer

Restrained Policy and Careless Execution: Allied Strategic Bombing on the Netherlands in the Second World War

DTIC Science & Technology

2011-05-19

food and money to the crew of a downed British Wellington. Source: A. Korthals Altes, Luchtgevaar: Luchtaanvallen op Nederland , 1940- 1945...of the Liberation of Europe (New York: Free Press, 2008). 6Chris van der Heijden, Grijs Verleden: Nederland en de Tweede Wereldoorlog (Amsterdam... Nederland Tijdens de Tweede Wereldoorlog (Den Haag, The Netherlands: Studiegroep Luchtoorlog 1939-1945, 2008), 141-143. 3 Endless Controversy Strategic

Goal-Driven Autonomy in a Navy Strategy Simulation

DTIC Science & Technology

2010-01-01

Goldman R . (2007). Hotride: Hierarchical ordered task replanning in dynamic environments. In F. Ingrand, & K. Rajan (Eds.) Planning and Plan...www.mbari.org/autonomy/ICAPS07-workshop] van den Briel, M., Sanchez, R ., Do, M.B., & Kambhampati, S. (2004). Effective approaches for partial satisfaction...Perpetual self-aware cognitive agents. AI Magazine, 28(1), 32-45. Dearden, R ., Meuleau, N., Ramakrishnan, S., Smith, D., & Washington, R . (2003

Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Atlantic): Bluefish

DTIC Science & Technology

1989-04-01

Invertebrates (South Atlantic) BLUEFISH AA I.,,bWU . . Coastal Ecology Group *Fish and Wildlife Service Waterways Experiment Station U.S. Department of the...Requirements of Coastal Fishes and Invertebrates (South Atlantic) BLUEFISH by J. Douglas Oliver, Michael J. Van Den Avyle, and Earl L. Bozeman, Jr. Georgia...Marine Fisheries Service, Panama City, Florida,for reviewing this manuscript. vi Figure 1. Bluefish . BLUEFISH NOMENCLATURE/TAXONOMY/RANGE westward to

Do People Take Stimulus Correlations into Account in Visual Search (Open Source)

DTIC Science & Technology

2016-03-10

RESEARCH ARTICLE Do People Take Stimulus Correlations into Account in Visual Search ? Manisha Bhardwaj1, Ronald van den Berg2,3, Wei Ji Ma2,4...visual search experiments, distractors are often statistically independent of each other. However, stimuli in more naturalistic settings are often...contribute to bridging the gap between artificial and natural visual search tasks. Introduction Visual target detection in displays consisting of multiple

VIEW NORTH, SHOWING SOUTH END OF BRIDGE LOOKING TOWARD VAN ...

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

VIEW NORTH, SHOWING SOUTH END OF BRIDGE LOOKING TOWARD VAN BUREN TOWNSHIP - Belleville Road Bridge, Spanning the Flat River at Burroughs Drive (replaced Burroughs Street Bridge), Lowell, Kent County, MI

Learning Styles versus the Rip Van Winkle Syndrome.

ERIC Educational Resources Information Center

Orsak, Lana

1990-01-01

Rip Van Winkle would not recognize Corsicana (Texas) High School since its curriculum coordinator began implementing learning styles techniques in various pilot programs. Lecturing to rows of bored students has been replaced by students' active involvement in group activities, listening centers, and tactile/kinesthetic exercises on the floor or at…

A 600,000 year long continental pollen record from Lake Van, eastern Turkey

NASA Astrophysics Data System (ADS)

Litt, T.; Pickarski, N.; Heumann, G.

2014-12-01

Lake Van is the fourth largest terminal lake in the world (38.5°N, 43 °E, volume 607 km3, area 3570 km2, maximum water depth 460 m), extending for 130 km WSW-ENE on the Eastern Anatolian High Plateau, Turkey. The sedimentary record of Lake Van, partly laminated, obtains a long and continuous continental sequence that covers multiple interglacial-glacial cycles. Promoted by the potential of the sedimentary sequence for reconstructing the paleoecological and paleoclimate development of the Near East, a deep drilling operation was carried out in 2010 supported by the International Continental Scientific Drilling Program (ICDP). The 119 m long continental record is based on a well-dated composite profile drilled on the so-called Ahlat Ridge in water depth of 360 m encompassing the last 600,000 years. It contains the longest continuous continental pollen record of the Quaternary in the entire Near East and central Asia obtained to date. It documents glacial and interglacial stages as well as pronounced interstadials encompassing the entire 600 ka of the sedimentary record. The cold-adapted vegetation in the Lake Van region during glacial stages and stadial substages can be described as dwarf-shrub steppe and desert steppe very similar to each other. The climax vegetation of the interglacial stages in the Lake Van region is characterized by an oak steppe-forest with pistachio and juniper. It is interesting to note that, in contrast to the atmospheric CO2 concentration from Antarctic ice cores or marine isotope values based on benthic foraminifera, there is no clear subdivision in the Lake Van pollen record between low-amplitude interglacials (cooler cycles) prior the mid-Brunhes event (MBE) at 430 ka and high-amplitude, post MBE interglacials. Lower CO2 concentrations in the atmosphere might be compensated by stronger insolation forcing during Marine Isotope Stages (MIS) 13a and 15a. A similar pattern can be observed during the triplicate interglacial complex MIS 7

Dispersion of the Vancomycin Resistance Genes vanA and vanC of Enterococcus Isolated from Nile Tilapia on Retail Sale: A Public Health Hazard.

PubMed

Osman, Kamelia M; Ali, Mohamed N; Radwan, Ismail; ElHofy, Fatma; Abed, Ahmed H; Orabi, Ahmed; Fawzy, Nehal M

2016-01-01

Although normally regarded harmless commensals, enterococci may cause a range of different infections in humans, including urinary tract infections, sepsis, and endocarditis. The acquisition of vancomycin resistance by enterococci (VRE) has seriously affected the treatment and infection control of these organisms. VRE are frequently resistant to all antibiotics that are effective treatment for vancomycin-susceptible enterococci, which leaves clinicians treating VRE infections with limited therapeutic options. With VRE emerging as a global threat to public health, we aimed to isolate, identify enterococci species from tilapia and their resistance to van-mediated glycopeptide (vanA and vanC) as well as the presence of enterococcal surface protein (esp) using conventional and molecular methods. The cultural, biochemical (Vitek 2 system) and polymerase chain reaction results revealed eight Enterococcus isolates from the 80 fish samples (10%) to be further identified as E. faecalis (6/8, 75%) and E gallinarum (2/8, 25%). Intraperitoneal injection of healthy Nile tilapia with the eight Enterococcus isolates caused significant morbidity (70%) within 3 days and 100% mortality at 6 days post-injection with general signs of septicemia. All of the eight Enterococcus isolates were found to be resistant to tetracycline. The 6/6 E. faecalis isolates were susceptible for penicillin, nitrofurantoin, gentamicin, and streptomycin. On the other hand 5/6 were susceptible for ampicillin, vancomycin, chloramphenicol, and ciprofloxacin. The two isolates of E. gallinarum were sensitive to rifampicin and ciprofloxacin and resistant to vancomycin, chloramphenicol, and erythromycin. Molecular characterization proved that they all presented the prototypic vanC element. On the whole, one of the two vancomycin resistance gene was present in 3/8 of the enterococci isolates, while the esp virulence gene was present in 1/8 of the enterococci isolates. The results in this study emphasize the

Serine and alanine racemase activities of VanT: a protein necessary for vancomycin resistance in Enterococcus gallinarum BM4174.

PubMed

Arias, C A; Weisner, J; Blackburn, J M; Reynolds, P E

2000-07-01

Vancomycin resistance in Enterococcus gallinarum results from the production of UDP-MurNAc-pentapeptide[D-Ser]. VanT, a membrane-bound serine racemase, is one of three proteins essential for this resistance. To investigate the selectivity of racemization of L-Ser or L-Ala by VanT, a strain of Escherichia coli TKL-10 that requires D-Ala for growth at 42 degrees C was used as host for transformation experiments using plasmids containing the full-length vanT from Ent. gallinarum or the alanine racemase gene (alr) of Bacillus stearothermophilus: both plasmids were able to complement E. coli TKL-10 at 42 degrees C. No alanine or serine racemase activities were detected in the host strain E. coli TKL-10 grown at 30, 34 or 37 degrees C. Serine and alanine racemase activities were found almost exclusively (96%) in the membrane fraction of E. coli TKL-10/pCA4(vanT): the alanine racemase activity of VanT was 14% of the serine racemase activity in both E. coli TKL-10/pCA4(vanT) and E. coli XL-1 Blue/pCA4(vanT). Alanine racemase activity was present mainly (95%) in the cytoplasmic fraction of E. coli TKL-10/pJW40(alr), with a trace (1.6%) of serine racemase activity. Additionally, DNA encoding the soluble domain of VanT was cloned and expressed in E. coli M15 as a His-tagged polypeptide and purified: this polypeptide also exhibited both serine and alanine racemase activities; the latter was approximately 18% of the serine racemase activity, similar to that of the full-length, membrane-bound enzyme. N-terminal sequencing of the purified His-tagged polypeptide revealed a single amino acid sequence, indicating that the formation of heterodimers between subunits of His-tagged C-VanT and endogenous alanine racemases from E. coli was unlikely. The authors conclude that the membrane-bound serine racemase VanT also has alanine racemase activity but is able to racemize serine more efficiently than alanine, and that the cytoplasmic domain is responsible for the racemase activity.

Martin Van Buren National Historic Site alternative transportation feasibility study.

DOT National Transportation Integrated Search

2012-05-31

The Martin Van Buren National Historic Site (MVBNHS) Alternative Transportation Feasibility Study examines the feasibility of : alternative transportation system (ATS) service to MVBNHS. The report investigates opportunities for a shuttle carrying vi...

Accurate van der Waals force field for gas adsorption in porous materials.

PubMed

Sun, Lei; Yang, Li; Zhang, Ya-Dong; Shi, Qi; Lu, Rui-Feng; Deng, Wei-Qiao

2017-09-05

An accurate van der Waals force field (VDW FF) was derived from highly precise quantum mechanical (QM) calculations. Small molecular clusters were used to explore van der Waals interactions between gas molecules and porous materials. The parameters of the accurate van der Waals force field were determined by QM calculations. To validate the force field, the prediction results from the VDW FF were compared with standard FFs, such as UFF, Dreiding, Pcff, and Compass. The results from the VDW FF were in excellent agreement with the experimental measurements. This force field can be applied to the prediction of the gas density (H 2 , CO 2 , C 2 H 4 , CH 4 , N 2 , O 2 ) and adsorption performance inside porous materials, such as covalent organic frameworks (COFs), zeolites and metal organic frameworks (MOFs), consisting of H, B, N, C, O, S, Si, Al, Zn, Mg, Ni, and Co. This work provides a solid basis for studying gas adsorption in porous materials. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Letters from a suicide: Van Gogh and his sister.

PubMed

Lester, David

2010-04-01

An analysis of trends over a 3-yr. period in the letters of Vincent Van Gogh to his sister as the time of his suicide approached identified 8 trends, including an increase in words concerned with anxiety and words concerned with the past.

Implantate für den Bandscheibenersatz (Stand 1993)

NASA Astrophysics Data System (ADS)

Mathey, Michael; Wintermantel, Erich

Die Bandscheiben sind besonders betroffen von Fehlhaltungen und -stellungen der Wirbelsäule. Sie unterliegen als grösstes zusammenhängendes, nicht vaskularisiertes Gewebe im Menschen, statisch und dynamisch extrem belastet, besonders der Alterung. Um die teilweise sehr starken Schmerzen bei Bandscheibenschädigungen zu lindern, ist eine Operation vielfach die einzige Hilfe. Bei dieser Operation (Nukleotomie) entfernt man das aus der Bandscheibe ausgetretene Gewebe des Gallertkerns (nucleus pulposus), welches durch Druck auf die Nervenstränge im Bereich der Wirbelsäule die Beschwerden (Ischias-Schmerz) verursacht hat. Nach der Entfernung des Gallertkerns werden die auftretenden Kräfte bei veränderter Biomechanik übertragen. Dabei erhalten die Zwischenwirbelgelenke (Facettengelenke) eine erheblich grössere Flächenpressung als dies bei intakter Bandscheibe der Fall war. Die höhere Flächenpressung kommt durch die Verringerung des Abstandes zwischen den oberen und unteren Deckplatten der benachbarten Wirbelkörper zustande, zwischen denen sich der Gallertkern befand. Durch geeignetes Training der Rückenmuskulatur kann eine Stabilisierung des operierten Bandscheibensegmentes erreicht werden, jedoch ist es eine klinische Erfahrung, dass die meisten Patienten, die momentan durch die Operation schmerzfrei geworden sind, keine adäquate zusätzliche sportliche Betätigung auf sich nehmen.

Kwalificate/Classificatie van Explosieve Stoffen en Munitie. Rapport 2. Testontwikkeling (Qualification/Classification Explosive Materials and Munition. 2. Test Development)

DTIC Science & Technology

1992-11-01

beschermkap van het apparaat af te halen , waardoor bij een eventuele ontsteking het energetisch materiaal (al dan niet brandend) weg kan springen. Tevens...TNO-DefensieonderzoekPr TN TNO-rapport Kwalificatielclassificatie van explosieve stoffen ~ PML 1992-68 en munitief Rapport ]I: Testontwikkeling...rapport Kwalificatielclassificatie van explosieve stoffen PML 1992-68 en munitie Rapport f1: Testontwikkeling november 1992 ~~- ExorrIaar no:- 1ýMI

11. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

11. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 INTERIOR DETAIL OF FRAME CONSTRUCTION - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

Van der Waals equation of state revisited: importance of the dispersion correction.

PubMed

de Visser, Sam P

2011-04-28

One of the most basic equations of state describing nonideal gases and liquids is the van der Waals equation of state, and as a consequence, it is generally taught in most first year undergraduate chemistry courses. In this work, we show that the constants a and b in the van der Waals equation of state are linearly proportional to the polarizability volume of the molecules in a gas or liquid. Using this information, a new thermodynamic one-parameter equation of state is derived that contains experimentally measurable variables and physics constants only. This is the first equation of state apart from the Ideal Gas Law that contains experimentally measurable variables and physics constants only, and as such, it may be a very useful and practical equation for the description of dilute gases and liquids. The modified van der Waals equation of state describes pV as the sum of repulsive and attractive intermolecular interaction energies that are represented by an exponential repulsion function between the electron clouds of the molecules and a London dispersion component, respectively. The newly derived equation of state is tested against experimental data for several gas and liquid examples, and the agreement is satisfactory. The description of the equation of state as a one-parameter function also has implications on other thermodynamic functions, such as critical parameters, virial coefficients, and isothermal compressibilities. Using our modified van der Waals equation of state, we show that all of these properties are a function of the molecular polarizability volume. Correlations of experimental data confirm the derived proportionalities.

James Van Allen and His Namesake NASA Mission

NASA Astrophysics Data System (ADS)

Baker, D. N.; Hoxie, V. C.; Jaynes, A.; Kale, A.; Kanekal, S. G.; Li, X.; Reeves, G. D.; Spence, H. E.

2013-12-01

In many ways, James A. Van Allen defined and "invented" modern space research. His example showed the way for government-university partners to pursue basic research that also served important national and international goals. He was a tireless advocate for space exploration and for the role of space science in the spectrum of national priorities.

Van der Waals interactions and the limits of isolated atom models at interfaces

PubMed Central

Kawai, Shigeki; Foster, Adam S.; Björkman, Torbjörn; Nowakowska, Sylwia; Björk, Jonas; Canova, Filippo Federici; Gade, Lutz H.; Jung, Thomas A.; Meyer, Ernst

2016-01-01

Van der Waals forces are among the weakest, yet most decisive interactions governing condensation and aggregation processes and the phase behaviour of atomic and molecular matter. Understanding the resulting structural motifs and patterns has become increasingly important in studies of the nanoscale regime. Here we measure the paradigmatic van der Waals interactions represented by the noble gas atom pairs Ar–Xe, Kr–Xe and Xe–Xe with a Xe-functionalized tip of an atomic force microscope at low temperature. Individual rare gas atoms were fixed at node sites of a surface-confined two-dimensional metal–organic framework. We found that the magnitude of the measured force increased with the atomic radius, yet detailed simulation by density functional theory revealed that the adsorption induced charge redistribution strengthened the van der Waals forces by a factor of up to two, thus demonstrating the limits of a purely atomic description of the interaction in these representative systems. PMID:27174162

Dynamics of three coupled van der Pol oscillators with application to circadian rhythms

NASA Astrophysics Data System (ADS)

Rompala, Kevin; Rand, Richard; Howland, Howard

2007-08-01

In this work we study a system of three van der Pol oscillators. Two of the oscillators are identical, and are not directly coupled to each other, but rather are coupled via the third oscillator. We investigate the existence of the in-phase mode in which the two identical oscillators have the same behavior. To this end we use the two variable expansion perturbation method (also known as multiple scales) to obtain a slow flow, which we then analyze using the computer algebra system MACSYMA and the numerical bifurcation software AUTO. Our motivation for studying this system comes from the presence of circadian rhythms in the chemistry of the eyes. We model the circadian oscillator in each eye as a van der Pol oscillator. Although there is no direct connection between the two eyes, they are both connected to the brain, especially to the pineal gland, which is here represented by a third van der Pol oscillator.

Leon Van Speybroeck Wins Astrophysics Bruno Rossi Prize

NASA Technical Reports Server (NTRS)

2002-01-01

Leon Van Speybroeck of the Harvard-Smithsonian Center for Astrophysics in Cambridge Massachusetts was awarded the 2002 Bruno Rossi Prize of the High-Energy Astrophysics Division of the American Astronomy Society. The Rossi Prize is an arnual recognition of significant contributions in high-energy astrophysics in honor of the Massachusetts Institute of Technology's late Professor Bruno Rossi, an authority on cosmic ray physics and a pioneer in the field of x-ray astronomy. Van Speybroeck, who led the effort to design and make the x-ray mirrors for NASA's premier Chandra X-Ray Observatory, was recognized for a career of stellar achievements in designing precision x-ray optics. As Telescope Scientist for Chandra, he has worked for more than 20 years with a team that includes scientists and engineers from the Harvard-Smithsonian, NASA's Marshall Space Flight Center, TRW, Inc., Huhes-Danbury (now B.F. Goodrich Aerospace), Optical Coating Laboratories, Inc., and Eastman-Kodak on all aspects of the x-ray mirror assembly that is the heart of the observatory.

Alternative Fuels Data Center: Propane Vans Keep Kansas City Transportation

Science.gov Websites

anxiety. More recently, the company has been exploring dedicated-propane vehicles in Kansas City to ensure technologies and petroleum-use reduction strategies, then deployed bi-fuel vans; currently exploring dedicated

A discussion of the socio-economic losses and shelter impacts from the Van, Turkey Earthquakes of October and November 2011

NASA Astrophysics Data System (ADS)

Daniell, J. E.; Khazai, B.; Wenzel, F.; Kunz-Plapp, T.; Vervaeck, A.; Muehr, B.; Markus, M.

2012-04-01

The Van earthquake in 2011 hit at 10:41 GMT (13:41 Local) on Sunday, October 23rd, 2011. It was a Mw7.1-7.3 event located at a depth of around 10 km with the epicentre located directly between Ercis (pop. 75,000) and Van (pop. 370,000). Since then, the CEDIM Forensic Analysis Group (using a team of seismologists, engineers, sociologists and meteorologists) and www.earthquake-report.com has reported and analysed on the Van event. In addition, many damaging aftershocks occurring after the main eventwere analysed including a major aftershock centered in Van-Edremit on November 9th, 2011, causing much additional losses. The province of Van has around 1.035 million people as of the last census. The Van province is one of the poorest in Turkey and has much inequality between the rural and urban centers with an average HDI (Human Development Index) around that of Bhutan or Congo. The earthquakes are estimated to have caused 604 deaths (23 October) and 40 deaths (9 November); mostly due to falling debris and house collapse). In addition, between 1 billion TRY to 4 billion TRY (approx. 555 million USD - 2.2 billion USD) is estimated as total economic losses. This represents around 17 to 66% of the provincial GDP of the Van Province (approx. 3.3 billion USD) as of 2011. From the CATDAT Damaging Earthquakes Database, major earthquakes such as this one have occurred in the year 1111 causing major damage and having a magnitude around 6.5-7. In the year 1646 or 1648, Van was again struck by a M6.7 quake killing around 2000 people. In 1881, a M6.3 earthquake near Van killed 95 people. Again, in 1941, a M5.9 earthquake affected Ercis and Van killing between 190 and 430 people. 1945-1946 as well as 1972 brought again damaging and casualty-bearing earthquakes to the Van province. In 1976, the Van-Muradiye earthquake struck the border region with a M7, killing around 3840 people and causing around 51,000 people to become homeless. Key immediate lessons from similar historic

Evaluation of BBL CHROMagar VanRE for detection of vancomycin-resistant Enterococci in rectal swab specimens.

PubMed

Stamper, Paul D; Shulder, Stephanie; Bekalo, Pearl; Manandhar, Deepika; Ross, Tracy L; Speser, Sharon; Kingery, Julie; Carroll, Karen C

2010-11-01

A study was performed on 517 surveillance rectal swabs to evaluate a selective and differential chromogenic medium, the BBL CHROMagar VanRE (CVRE), which enables recovery and identification of VanA- and VanB-containing Enterococcus faecium (ENFM) and Enterococcus faecalis (ENFS) isolates. Compared to BBL Enterococcosel agar, a bile-esculin-azide-vancomycin (BEAV) agar, the initial overall sensitivity, specificity, and positive and negative predictive values of CVRE for the detection of vancomycin-resistant ENFM and ENFS were 99.1% and 94.8% and 84.2% and 99.7%, respectively. Among our patient population, more vancomycin-resistant enterococci (VRE) were recovered with CVRE than BEAV.

Evaluation of BBL CHROMagar VanRE for Detection of Vancomycin-Resistant Enterococci in Rectal Swab Specimens▿

PubMed Central

Stamper, Paul D.; Shulder, Stephanie; Bekalo, Pearl; Manandhar, Deepika; Ross, Tracy L.; Speser, Sharon; Kingery, Julie; Carroll, Karen C.

2010-01-01

A study was performed on 517 surveillance rectal swabs to evaluate a selective and differential chromogenic medium, the BBL CHROMagar VanRE (CVRE), which enables recovery and identification of VanA- and VanB-containing Enterococcus faecium (ENFM) and Enterococcus faecalis (ENFS) isolates. Compared to BBL Enterococcosel agar, a bile-esculin-azide-vancomycin (BEAV) agar, the initial overall sensitivity, specificity, and positive and negative predictive values of CVRE for the detection of vancomycin-resistant ENFM and ENFS were 99.1% and 94.8% and 84.2% and 99.7%, respectively. Among our patient population, more vancomycin-resistant enterococci (VRE) were recovered with CVRE than BEAV. PMID:20739492

Probing low-energy hyperbolic polaritons in van der Waals crystals with an electron microscope.

PubMed

Govyadinov, Alexander A; Konečná, Andrea; Chuvilin, Andrey; Vélez, Saül; Dolado, Irene; Nikitin, Alexey Y; Lopatin, Sergei; Casanova, Fèlix; Hueso, Luis E; Aizpurua, Javier; Hillenbrand, Rainer

2017-07-21

Van der Waals materials exhibit intriguing structural, electronic, and photonic properties. Electron energy loss spectroscopy within scanning transmission electron microscopy allows for nanoscale mapping of such properties. However, its detection is typically limited to energy losses in the eV range-too large for probing low-energy excitations such as phonons or mid-infrared plasmons. Here, we adapt a conventional instrument to probe energy loss down to 100 meV, and map phononic states in hexagonal boron nitride, a representative van der Waals material. The boron nitride spectra depend on the flake thickness and on the distance of the electron beam to the flake edges. To explain these observations, we developed a classical response theory that describes the interaction of fast electrons with (anisotropic) van der Waals slabs, revealing that the electron energy loss is dominated by excitation of hyperbolic phonon polaritons, and not of bulk phonons as often reported. Thus, our work is of fundamental importance for interpreting future low-energy loss spectra of van der Waals materials.Here the authors adapt a STEM-EELS system to probe energy loss down to 100 meV, and apply it to map phononic states in hexagonal boron nitride, revealing that the electron loss is dominated by hyperbolic phonon polaritons.

van der Waals interactions between nanostructures: Some analytic results from series expansions

NASA Astrophysics Data System (ADS)

Stedman, T.; Drosdoff, D.; Woods, L. M.

2014-01-01

The van der Waals force between objects of nontrivial geometries is considered. A technique based on a perturbation series approach is formulated in the dilute limit. We show that the dielectric response and object size can be decoupled and dominant contributions in terms of object separations can be obtained. This is a powerful method, which enables straightforward calculations of the interaction for different geometries. Our results for planar structures, such as thin sheets, infinitely long ribbons, and ribbons with finite dimensions, may be applicable for nanostructured devices where the van der Waals interaction plays an important role.

Photovoltaic Effect in an Electrically Tunable van der Waals Heterojunction

PubMed Central

2014-01-01

Semiconductor heterostructures form the cornerstone of many electronic and optoelectronic devices and are traditionally fabricated using epitaxial growth techniques. More recently, heterostructures have also been obtained by vertical stacking of two-dimensional crystals, such as graphene and related two-dimensional materials. These layered designer materials are held together by van der Waals forces and contain atomically sharp interfaces. Here, we report on a type-II van der Waals heterojunction made of molybdenum disulfide and tungsten diselenide monolayers. The junction is electrically tunable, and under appropriate gate bias an atomically thin diode is realized. Upon optical illumination, charge transfer occurs across the planar interface and the device exhibits a photovoltaic effect. Advances in large-scale production of two-dimensional crystals could thus lead to a new photovoltaic solar technology. PMID:25057817

Emergence of vancomycin resistance in the genus Streptococcus: characterization of a vanB transferable determinant in Streptococcus bovis.

PubMed Central

Poyart, C; Pierre, C; Quesne, G; Pron, B; Berche, P; Trieu-Cuot, P

1997-01-01

Streptococcus bovis NEM760 was isolated from a stool swab collected on admission from a patient as surveillance for vancomycin-resistant enterococci. Strain NEM760 was identified as S. bovis by conventional biochemical methods and partial sequence analysis of its 16S rRNA. This strain was resistant to a low level of vancomycin (MIC, 64 micrograms/ml) but was susceptible to teicoplanin (MIC, 1 micrograms/ml), and vancomycin induced resistance to both glycopeptides. The presence of a vanB-related gene in NEM760 was demonstrated in a PCR assay which enabled specific amplification of a 635-hp internal segment of vanB. Sequence analysis of the corresponding PCR product revealed that it was highly homologous (96% identity) to the prototype vanB sequence of Enterococcus faecalis V583. The VanB resistance of determinant of S. bovis NEM760 was transferred by conjugation to E. faecalis and Enterococcus faecium at a similar frequency of 2 x 10(-5) per donor. SmaI-digested genomic DNAs of independently obtained transconjugants of E. faecalis and E. faecium were analyzed by pulsed-field gel electrophoresis and Southern hybridization with a vanB DNA probe. The electrophoretic and hybridization patterns obtained with all transconjugants of the same species were indistinguishable and revealed vanB-containing chromosomal insertions of approximately 100 kb. These results suggest that the genes mediating VanB-type resistance in S. bovis NEM760 are part of large transferable genetic elements. The results presented in the report demonstrate for the first time the role of streptococci in the dissemination of vancomycin resistance among gram-positive bacteria. PMID:8980749

Light scattering, aerosols, clouds, climate, Hendrik van de Hulst, and I

NASA Astrophysics Data System (ADS)

Chylek, Petr

2018-02-01

It is not often that I have the opportunity to write something that is not a scientific paper, and I am thankful for this opportunity to express my thoughts with regard to pursuits that are greater than those of science. In this van de Hulst essay, to honor Hendrik van de Hulst, I briefly summarize a few points from Hendrik's life that I find especially interesting, including his interests in spiritual (or religious) aspects of life, and his decision to avoid involvement in nucleation problems, a critical and basic uncertainty of current climate models. After that, I present briefly a few episodes from my own experiences as an apprentice of science and life.

The nonlinear effect of resistive inhomogeneities on van der Pauw measurements

NASA Astrophysics Data System (ADS)

Koon, Daniel W.

2005-03-01

The resistive weighting function [D. W. Koon and C. J. Knickerbocker, Rev. Sci. Instrum. 63, 207 (1992)] quantifies the effect of small local inhomogeneities on van der Pauw resistivity measurements, but assumes such effects to be linear. This talk will describe deviations from linearity for a square van der Pauw geometry, modeled using a 5 x 5 grid network of discrete resistors and introducing both positive and negative perturbations to local resistors, covering nearly two orders of magnitude in -δρ/ρ or -δσ/σ. While there is a relatively modest quadratic nonlinearity for inhomogeneities of decreasing conductivity, the nonlinear term for inhomogeneities of decreasing resistivity is approximately cubic and can exceed the linear term.

A Polarimetric Extension of the van Cittert-Zernike Theorem for Use with Microwave Interferometers

NASA Technical Reports Server (NTRS)

Piepmeier, J. R.; Simon, N. K.

2004-01-01

The van Cittert-Zernike theorem describes the Fourier-transform relationship between an extended source and its visibility function. Developments in classical optics texts use scalar field formulations for the theorem. Here, we develop a polarimetric extension to the van Cittert-Zernike theorem with applications to passive microwave Earth remote sensing. The development provides insight into the mechanics of two-dimensional interferometric imaging, particularly the effects of polarization basis differences between the scene and the observer.

Li intercalation in graphite: A van der Waals density-functional study

NASA Astrophysics Data System (ADS)

Hazrati, E.; de Wijs, G. A.; Brocks, G.

2014-10-01

Modeling layered intercalation compounds from first principles poses a problem, as many of their properties are determined by a subtle balance between van der Waals interactions and chemical or Madelung terms, and a good description of van der Waals interactions is often lacking. Using van der Waals density functionals we study the structures, phonons and energetics of the archetype layered intercalation compound Li-graphite. Intercalation of Li in graphite leads to stable systems with calculated intercalation energies of -0.2 to -0.3 eV/Li atom, (referred to bulk graphite and Li metal). The fully loaded stage 1 and stage 2 compounds LiC6 and Li1 /2C6 are stable, corresponding to two-dimensional √{3 }×√{3 } lattices of Li atoms intercalated between two graphene planes. Stage N >2 structures are unstable compared to dilute stage 2 compounds with the same concentration. At elevated temperatures dilute stage 2 compounds easily become disordered, but the structure of Li3 /16C6 is relatively stable, corresponding to a √{7 }×√{7 } in-plane packing of Li atoms. First-principles calculations, along with a Bethe-Peierls model of finite temperature effects, allow for a microscopic description of the observed voltage profiles.

van der Waals torque and force between dielectrically anisotropic layered media.

PubMed

Lu, Bing-Sui; Podgornik, Rudolf

2016-07-28

We analyse van der Waals interactions between a pair of dielectrically anisotropic plane-layered media interacting across a dielectrically isotropic solvent medium. We develop a general formalism based on transfer matrices to investigate the van der Waals torque and force in the limit of weak birefringence and dielectric matching between the ordinary axes of the anisotropic layers and the solvent. We apply this formalism to study the following systems: (i) a pair of single anisotropic layers, (ii) a single anisotropic layer interacting with a multilayered slab consisting of alternating anisotropic and isotropic layers, and (iii) a pair of multilayered slabs each consisting of alternating anisotropic and isotropic layers, looking at the cases where the optic axes lie parallel and/or perpendicular to the plane of the layers. For the first case, the optic axes of the oppositely facing anisotropic layers of the two interacting slabs generally possess an angular mismatch, and within each multilayered slab the optic axes may either be the same or undergo constant angular increments across the anisotropic layers. In particular, we examine how the behaviors of the van der Waals torque and force can be "tuned" by adjusting the layer thicknesses, the relative angular increment within each slab, and the angular mismatch between the slabs.

8. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

8. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 BRICK NOGGING AND ORIGINAL WEATHERBOARDING OF SOUTH ELEVATION - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

Accurate van der Waals coefficients from density functional theory

PubMed Central

Tao, Jianmin; Perdew, John P.; Ruzsinszky, Adrienn

2012-01-01

The van der Waals interaction is a weak, long-range correlation, arising from quantum electronic charge fluctuations. This interaction affects many properties of materials. A simple and yet accurate estimate of this effect will facilitate computer simulation of complex molecular materials and drug design. Here we develop a fast approach for accurate evaluation of dynamic multipole polarizabilities and van der Waals (vdW) coefficients of all orders from the electron density and static multipole polarizabilities of each atom or other spherical object, without empirical fitting. Our dynamic polarizabilities (dipole, quadrupole, octupole, etc.) are exact in the zero- and high-frequency limits, and exact at all frequencies for a metallic sphere of uniform density. Our theory predicts dynamic multipole polarizabilities in excellent agreement with more expensive many-body methods, and yields therefrom vdW coefficients C6, C8, C10 for atom pairs with a mean absolute relative error of only 3%. PMID:22205765

Franckeite as a naturally occurring van der Waals heterostructure

PubMed Central

Molina-Mendoza, Aday J.; Giovanelli, Emerson; Paz, Wendel S.; Niño, Miguel Angel; Island, Joshua O.; Evangeli, Charalambos; Aballe, Lucía; Foerster, Michael; van der Zant, Herre S. J.; Rubio-Bollinger, Gabino; Agraït, Nicolás; Palacios, J. J.; Pérez, Emilio M.; Castellanos-Gomez, Andres

2017-01-01

The fabrication of van der Waals heterostructures, artificial materials assembled by individual stacking of 2D layers, is among the most promising directions in 2D materials research. Until now, the most widespread approach to stack 2D layers relies on deterministic placement methods, which are cumbersome and tend to suffer from poor control over the lattice orientations and the presence of unwanted interlayer adsorbates. Here, we present a different approach to fabricate ultrathin heterostructures by exfoliation of bulk franckeite which is a naturally occurring and air stable van der Waals heterostructure (composed of alternating SnS2-like and PbS-like layers stacked on top of each other). Presenting both an attractive narrow bandgap (<0.7 eV) and p-type doping, we find that the material can be exfoliated both mechanically and chemically down to few-layer thicknesses. We present extensive theoretical and experimental characterizations of the material's electronic properties and crystal structure, and explore applications for near-infrared photodetectors. PMID:28194037

Impact of Polarizing Non-Lambertian Surface and Volume Scattering on Polarized Light Signatures: Importance to Remote Sensing

DTIC Science & Technology

2016-12-08

RVIL Kirtland AFB, NM 87117-5776 Official Record Copy AFRL /RVBYI/Jeannette van den Bosch 1 cy Approved for public release; distribution is... AFRL -RV-PS- TR-2017-0156 AFRL -RV-PS- TR-2017-0156 IMPACT OF POLARIZING NON-LAMBERTIAN SURFACE AND VOLUME SCATTERING ON POLARIZED LIGHT...3550 Aberdeen Ave SE AIR FORCE MATERIEL COMMAND KIRTLAND AIR FORCE BASE, NM 87117-5776 DTIC COPY NOTICE AND SIGNATURE PAGE Using Government

Frostbite in Ski Boots for Marines

DTIC Science & Technology

2005-05-01

tested with regards to thermal comfort , manifested by insulation measurements, water vapour transport and water tightness of the combination. In the...et.al. 2004), you can determine the water vapour transport and heat resistance as important parameters for thermal comfort . On three subsequent...morbidity and risk factors. (in Dutch). Schols, E.H.M., Eijnde, W. van den & Heus, R (2004). A method for assessing thermal comfort of shoes using a

Dynamic Resource Allocation to Improve Service Performance in Order Fulfillment Systems

DTIC Science & Technology

2009-01-01

efficient system uses economies of scale at two points: orders are batched before processing, which reduces processing costs, and processed or- ders ...the ef- fects of batching on order picking processes is well-researched and well-understood ( van den Berg and Gademann, 1999). Because orders are...a final so- journ time distribution. Our work builds on existing research in matrix-geometric methods by Neuts (1981), Asmussen and M0ller (2001

Cross-scale observations of the 2015 St. Patrick's day storm: THEMIS, Van Allen Probes, and TWINS

DOE PAGES

Goldstein, J.; Angelopoulos, V.; De Pascuale, S.; ...

2016-12-10

In this paper, we present cross-scale magnetospheric observations of the 17 March 2015 (St. Patrick's Day) storm, by Time History of Events and Macroscale Interactions during Substorms (THEMIS), Van Allen Probes (Radiation Belt Storm Probes), and Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS), plus upstream ACE/Wind solar wind data. THEMIS crossed the bow shock or magnetopause 22 times and observed the magnetospheric compression that initiated the storm. Empirical models reproduce these boundary locations within 0.7 R E. Van Allen Probes crossed the plasmapause 13 times; test particle simulations reproduce these encounters within 0.5 R E. Before the storm, Van Allen Probesmore » measured quiet double-nose proton spectra in the region of corotating cold plasma. About 15 min after a 0605 UT dayside southward turning, Van Allen Probes captured the onset of inner magnetospheric convection, as a density decrease at the moving corotation-convection boundary (CCB) and a steep increase in ring current (RC) proton flux. During the first several hours of the storm, Van Allen Probes measured highly dynamic ion signatures (numerous injections and multiple spectral peaks). Sustained convection after ~1200 UT initiated a major buildup of the midnight-sector ring current (measured by RBSP A), with much weaker duskside fluxes (measured by RBSP B, THEMIS a and THEMIS d). A close conjunction of THEMIS d, RBSP A, and TWINS 1 at 1631 UT shows good three-way agreement in the shapes of two-peak spectra from the center of the partial RC. A midstorm injection, observed by Van Allen Probes and TWINS at 1740 UT, brought in fresh ions with lower average energies (leading to globally less energetic spectra in precipitating ions) but increased the total pressure. Finally, the cross-scale measurements of 17 March 2015 contain significant spatial, spectral, and temporal structure.« less

Understanding the nanoscale local buckling behavior of vertically aligned MWCNT arrays with van der Waals interactions

NASA Astrophysics Data System (ADS)

Li, Yupeng; Kim, Hyung-Ick; Wei, Bingqing; Kang, Junmo; Choi, Jae-Boong; Nam, Jae-Do; Suhr, Jonghwan

2015-08-01

The local buckling behavior of vertically aligned carbon nanotubes (VACNTs) has been investigated and interpreted in the view of a collective nanotube response by taking van der Waals interactions into account. To the best of our knowledge, this is the first report on the case of collective VACNT behavior regarding van der Waals force among nanotubes as a lateral support effect during the buckling process. The local buckling propagation and development of VACNTs were experimentally observed and theoretically analyzed by employing finite element modeling with lateral support from van der Waals interactions among nanotubes. Both experimental and theoretical analyses show that VACNTs buckled in the bottom region with many short waves and almost identical wavelengths, indicating a high mode buckling. Furthermore, the propagation and development mechanism of buckling waves follow the wave damping effect.The local buckling behavior of vertically aligned carbon nanotubes (VACNTs) has been investigated and interpreted in the view of a collective nanotube response by taking van der Waals interactions into account. To the best of our knowledge, this is the first report on the case of collective VACNT behavior regarding van der Waals force among nanotubes as a lateral support effect during the buckling process. The local buckling propagation and development of VACNTs were experimentally observed and theoretically analyzed by employing finite element modeling with lateral support from van der Waals interactions among nanotubes. Both experimental and theoretical analyses show that VACNTs buckled in the bottom region with many short waves and almost identical wavelengths, indicating a high mode buckling. Furthermore, the propagation and development mechanism of buckling waves follow the wave damping effect. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03581c

Generation of EMIC Waves Observed by Van Allen Probes at Low L-shells of Earth's Magnetosphere

NASA Astrophysics Data System (ADS)

Gamayunov, K. V.; Zhang, J.; Saikin, A.; Rassoul, H.

2017-12-01

In a multi-ion magnetospheric plasma, where the major species are H+, He+, and O+, the He-band of electromagnetic ion cyclotron (EMIC) waves is the dominant band observed in the inner magnetosphere, and waves are generally quasi-field-aligned inside the geostationary orbit. Almost all the satellite-based studies of EMIC waves before Van Allen Probes, however, have not reported waves below L 3.5. There is probably only one exception from the Akebono satellite where both the H-band and He-band EMIC waves were observed at L 2. The situation has changed dramatically after two Van Allen Probes spacecraft were launched on 30 August, 2012, and many EMIC wave events have been observed below L=4. The Van Allen Probes observations confirm that the He-band of EMIC waves is a dominant band in the inner magnetosphere, but the observation of the He-band waves below L=4 is a new and quite unexpected result compared to our knowledge about EMIC waves before the Van Allen Probes era. In addition, observations show that almost all the He-band EMIC waves are linearly polarized in the region L < 4. This result is also new and unexpected. Here we will present an observational test of the generation mechanism for the He-band EMIC waves observed by Van Allen Probes at L 2.8 on 18 March, 2013. All the plasma parameters, DC magnetic field, and energetic ion distribution functions will be taken from the Van Allen Probes observations during the EMIC wave event to calculate growth rates of EMIC waves. We will then identify the energetic ions responsible for instability, frequencies and normals generated, and physical mechanism of instability.

Cross-scale observations of the 2015 St. Patrick's day storm: THEMIS, Van Allen Probes, and TWINS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldstein, J.; Angelopoulos, V.; De Pascuale, S.

In this paper, we present cross-scale magnetospheric observations of the 17 March 2015 (St. Patrick's Day) storm, by Time History of Events and Macroscale Interactions during Substorms (THEMIS), Van Allen Probes (Radiation Belt Storm Probes), and Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS), plus upstream ACE/Wind solar wind data. THEMIS crossed the bow shock or magnetopause 22 times and observed the magnetospheric compression that initiated the storm. Empirical models reproduce these boundary locations within 0.7 R E. Van Allen Probes crossed the plasmapause 13 times; test particle simulations reproduce these encounters within 0.5 R E. Before the storm, Van Allen Probesmore » measured quiet double-nose proton spectra in the region of corotating cold plasma. About 15 min after a 0605 UT dayside southward turning, Van Allen Probes captured the onset of inner magnetospheric convection, as a density decrease at the moving corotation-convection boundary (CCB) and a steep increase in ring current (RC) proton flux. During the first several hours of the storm, Van Allen Probes measured highly dynamic ion signatures (numerous injections and multiple spectral peaks). Sustained convection after ~1200 UT initiated a major buildup of the midnight-sector ring current (measured by RBSP A), with much weaker duskside fluxes (measured by RBSP B, THEMIS a and THEMIS d). A close conjunction of THEMIS d, RBSP A, and TWINS 1 at 1631 UT shows good three-way agreement in the shapes of two-peak spectra from the center of the partial RC. A midstorm injection, observed by Van Allen Probes and TWINS at 1740 UT, brought in fresh ions with lower average energies (leading to globally less energetic spectra in precipitating ions) but increased the total pressure. Finally, the cross-scale measurements of 17 March 2015 contain significant spatial, spectral, and temporal structure.« less

Top-Level Players' Visual Control of Interceptive Actions: Bootsma and Van Wieringen (1990) 20 Years Later

ERIC Educational Resources Information Center

Bootsma, Reinoud J.; Fernandez, Laure; Morice, Antoine H. P.; Montagne, Gilles

2010-01-01

Using a two-step approach, Van Soest et al. (2010) recently questioned the pertinence of the conclusions drawn by Bootsma and Van Wieringen (1990) with respect to the visual regulation of an exemplary rapid interceptive action: the attacking forehand drive in table tennis. In the first step, they experimentally compared the movement behaviors of…

The Effect of Designed Geometry Teaching Lesson to the Candidate Teachers' Van Hiele Geometric Thinking Level

ERIC Educational Resources Information Center

Yilmaz, Gül Kaleli; Koparan, Timur

2016-01-01

The aim of this study is to find out how designed Geometry Teaching Lesson affects candidate teachers' Van Hiele Geometric Thinking Levels. For that purpose, 14 weeks long study was performed with 44 candidate teachers who were university students in Turkey. Van Hiele Geometric Thinking Test was applied to candidate teachers before and after…

Community Music during the New Deal: The Contributions of Willem Van de Wall and Max Kaplan

ERIC Educational Resources Information Center

Krikun, Andrew

2010-01-01

Willem Van de Wall (1887-1953) and Max Kaplan (1911-98) built careers spanning music performance, music education, adult education, sociology, social work, music therapy and community music. Willem Van de Wall was a seminal influence on the development of the fields of music therapy and adult education--researching the role of music in…

Determination of radiocarbon reservoir age of Lake Van by mineral magnetic and geochemical analysis

NASA Astrophysics Data System (ADS)

Makaroglu, Ozlem; Namik Cagatay, M.; Pesonen, Lauri J.; Orbay, Naci

2017-04-01

Lake Van is the largest soda lake in the world, located on the east Anatolian Plateau in Turkey. Its varved sediments provide an excellent archive of high-resolution paleoclimate record for the Near East. Varve counting and radiocarbon methods are therefore important dating techniques for investigating the Lake Van sedimentary paleoclimate record. In here we present detailed magnetic and geochemical record of Lake Van. We have studied 4.56 m (core VP0801) and 4.70 m (core VP0807) long cores recovered from 80 m and 65 m water depths located in SE and SW of Lake Van, respectively. Here, we have benefited from magnetic properties with associated remanent magnetization of the sediments from Lake Van to correlate the cores which contain of tephra layers. The cores cover the last 8.4 ka and lithologically include three laminated sedimentary units. From top to the bottom, the units were dated 4.2 ka BP-present, 5.4-4.2 ka BP and older than 5.4 ka BP. We identified tephra layers previously dated by varve counting, and used the varve ages to obtain age models for the cores. We also obtained a total of eight Accelerator Mass Spectrometry (AMS) 14C dates from total organic carbon (TOC) in the two cores, close to the tephra layers. Comparison of the varve ages of the AMS 14C dated samples with their corresponding AMS 14C dates indicates large differences, suggesting significant reservoir ages that range from 2.8 to 2.5 ka for 3.0-2.4 varve ka BP and from 2.8 to 3.3 ka for 8.0-5.9 varve ka BP. The results suggest that the reservoir age of the organic matter increases with the varve age of the sediments. This increase is mainly related to the rate of supply of "dead" carbon from the old carbonate rocks in the watershed of Lake Van, which was relatively higher during 8.4-5.9 ka than during 3.0-2.4 ka BP because of the higher atmospheric precipitation and higher rate of biochemical weathering during the former period.

Spectral asymmetry of atoms in the van der Waals potential of an optical nanofiber

NASA Astrophysics Data System (ADS)

Patterson, B. D.; Solano, P.; Julienne, P. S.; Orozco, L. A.; Rolston, S. L.

2018-03-01

We measure the modification of the transmission spectra of cold 87Rb atoms in the proximity of an optical nanofiber (ONF). Van der Waals interactions between the atoms an the ONF surface decrease the resonance frequency of atoms closer to the surface. An asymmetric spectra of the atoms holds information of their spatial distribution around the ONF. We use a far-detuned laser beam coupled to the ONF to thermally excite atoms at the ONF surface. We study the change of transmission spectrum of these atoms as a function of heating laser power. A semiclassical phenomenological model for the thermal excitation of atoms in the atom-surface van der Waals bound states is in good agreement with the measurements. This result suggests that van der Waals potentials could be used to trap and probe atoms at few nanometers from a dielectric surface, a key tool for hybrid photonic-atomic quantum systems.

The "Discernment of a Human Face" in Research: A Reaction to Van Hesteren's Human Science and Counselling.

ERIC Educational Resources Information Center

Knowles, Don

1986-01-01

Responds to Van Hesteren's advocacy of a "human science" orientation, using constructs and analytical methods from phenomenology to enhance methodology. Approves of a philosophy of science and of a self-perspective. Questions the need for complex terminology, Van Hesteren's definition of what constitutes research, quantification, and…

A review on data and predictions of water dielectric spectra for calculations of van der Waals surface forces.

PubMed

Wang, Jianlong; Nguyen, Anh V

2017-12-01

Van der Waals forces are one of the important components of intermolecular, colloidal and surface forces governing many phenomena and processes. The latest examples include the colloidal interactions between hydrophobic colloids and interfaces in ambient (non-degassed) water in which dissolved gases and nanobubbles are shown to affect the van der Waals attractions significantly. The advanced computation of van der Waals forces in aqueous systems by the Lifshitz theory requires reliable data for water dielectric spectra. In this paper we review the available predictions of water dielectric spectra for calculating colloidal and surface van der Waals forces. Specifically, the available experimental data for the real and imaginary parts of the complex dielectric function of liquid water in the microwave, IR and UV regions and various corresponding predictions of the water spectra are critically reviewed. The data in the UV region are critical, but the available predictions are still based on the outdated data obtained in 1974 (for frequency only up to 25.5eV). We also reviewed and analysed the experimental data obtained for the UV region in 2000 (for frequency up to 50eV) and 2015 (for frequency up to 100eV). The 1974 and 2000 data require extrapolations to higher frequencies needed for calculating the van der Waals forces but remain inaccurate. Our analysis shows that the latest data of 2015 do not require the extrapolation and can be used to reliably calculate van der Waals forces. The most recent water dielectric spectra gives the (non-retarded) Hamaker constant, A=5.20×10 -20 J, for foam films of liquid water. This review provides the most updated and reliable water dielectric spectra to compute van der Waals forces in aqueous systems. Copyright © 2017 Elsevier B.V. All rights reserved.

Martin Van Butchell (1735-1814): the eccentric, "kook" dentist of old London.

PubMed

Christen, A G; Christen, J A

1999-11-01

This article is a thumbnail sketch of the life and times of Martin Van Butchell (1735-1814), an eccentric, "kook" advertising dentist of Old London. Van Butchell earned these descriptive labels by displaying an unorthodox lifestyle, an outrageous personal appearance and outlandish, extreme and socially unacceptable personal and professional behaviors. While the general populace seemed to be fascinated by his strange ways, dentists and physicians were generally alienated by them. Nevertheless, he was considered a good dentist for his time, and he was extremely popular with his patients. Martin practiced dentistry for 23 years, and he practiced medicine as well, specializing in the treatment of ruptures and anal fistulas. Van Butchell interacted greatly with both John and William Hunter, who became two of the most famous and talented physicians, surgeons, anatomists and biologists of all time. When his first wife, Mary died, Martin arranged for her body to be embalmed and publicly displayed in his dental office for advertising purposes. Her preserved body was shown at the Museum of the Royal College of Surgeons (London), until it was destroyed by a German fire bomb in May, 1941. Mary's remains were on public display for a total of 166 years.

Spacecraft surface charging within geosynchronous orbit observed by the Van Allen Probes

DOE PAGES

Sarno-Smith, Lois K.; Larsen, Brian A.; Skoug, Ruth M.; ...

2016-02-27

Using the Helium Oxygen Proton Electron (HOPE) and Electric Field and Waves (EFW) instruments from the Van Allen Probes, we explored the relationship between electron energy fluxes in the eV and keV ranges and spacecraft surface charging. We present statistical results on spacecraft charging within geosynchronous orbit by L and MLT. An algorithm to extract the H+ charging line in the HOPE instrument data was developed to better explore intense charging events. Also, this study explored how spacecraft potential relates to electron number density, electron pressure, electron temperature, thermal electron current, and low-energy ion density between 1 and 210 eV.more » It is demonstrated that it is imperative to use both EFW potential measurements and the HOPE instrument ion charging line for examining times of extreme spacecraft charging of the Van Allen Probes. The results of this study show that elevated electron energy fluxes and high-electron pressures are present during times of spacecraft charging but these same conditions may also occur during noncharging times. Furthermore, we also show noneclipse significant negative charging events on the Van Allen Probes.« less

Spectral Properties of Dirac Billiards at the van Hove Singularities.

PubMed

Dietz, B; Klaus, T; Miski-Oglu, M; Richter, A; Wunderle, M; Bouazza, C

2016-01-15

We study distributions of the ratios of level spacings of rectangular and Africa-shaped superconducting microwave resonators containing circular scatterers on a triangular grid, so-called Dirac billiards (DBs). The high-precision measurements allowed the determination of, respectively, all 1651 and 1823 eigenfrequencies in the first two bands. The resonance densities are similar to that of graphene. They exhibit two sharp peaks at the van Hove singularities which separate the band structure into regions with a linear and a quadratic dispersion relation, respectively. In the vicinity of the van Hove singularities we observe rapid changes in, e.g., the wave function structure. Accordingly, we question whether the spectral properties are there still determined by the shapes of the DBs. The commonly used statistical measures are no longer applicable; however, we demonstrate in this Letter that the ratio distributions provide suitable measures.

Astronaut James D. van Hoften examines student experiment on Challenger

NASA Technical Reports Server (NTRS)

1984-01-01

Astronaut James D. van Hoften, 41-C mission specialist, holds an aluminum box full of honeybees. The experiment in earth orbit is duplicated with another colony of the bees on earth. This is an experiment submitted by student researchers.

An Empirical Introduction to the Concept of Chemical Element Based on Van Hiele's Theory of Level Transitions

ERIC Educational Resources Information Center

Vogelezang, Michiel; Van Berkel, Berry; Verdonk, Adri

2015-01-01

Between 1970 and 1990, the Dutch working group "Empirical Introduction to Chemistry" developed a secondary school chemistry education curriculum based on the educational vision of the mathematicians van Hiele and van Hiele-Geldof. This approach viewed learning as a process in which students must go through discontinuous level transitions…

Polar bear mother-offspring interactions in maternity dens in captivity.

PubMed

van Gessel, Chad

2015-01-01

Two female polar bears at Dierenrijk Zoo in the Netherlands were monitored at their maternity den one day before the birth of their cubs and three days postpartum. Each bear was monitored for 96 hr to document behaviour and vocalisations. The goal was to obtain insight into the differences between the mother that lost her litter and the other that successfully reared her cubs. Six groups of cub vocalisations were identified: Comfort, Discomfort, Distress, Nursing Attempts, Nursing, and No Vocalisation. Maternal vocalisations were split into three groups: Calm, Grooming, and Stress. Maternal behaviours were also split into three groups: Active, Rest, and Stress. The unsuccessful mother produced more stress vocalisations before and during the birth of her cub, whereas the successful mother appeared less stressed. Vocalisations indicate that the cub that died tried to nurse but was unsuccessful. The unsuccessful mother showed less stress as her cub got weaker and vocalised less. From this I suggest that maternal stress was a factor in cub mortality. © 2015 Wiley Periodicals, Inc.

View west along Lower Raceway, Van Houten Street, with (left ...

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

View west along Lower Raceway, Van Houten Street, with (left to right) Congdon Mill, Phoenix Mill, and Fabricolor Mill (a.k.a., Industry Mill, HAER No. NJ-15) - Great Falls/S. U. M. Power Canal System, Paterson, Passaic County, NJ

The effects of van der Waals attractions on cloud droplet growth by coalescence

NASA Technical Reports Server (NTRS)

Rogers, Jan R.; Davis, Robert H.

1990-01-01

The inclusion of van der Waals attractions in the interaction between cloud droplets has been recently shown to significantly increase the collision efficiencies of the smaller droplets. In the current work, these larger values for the collision efficiencies are used in a population dynamics model of the droplet size distribution evolution with time, in hopes of at least partially resolving the long-standing paradox in cloud microphysics that predicted rates of the onset of precipitation are generally much lower than those which are observed. Evolutions of several initial cloud droplet spectra have been tracked in time. Size evolutions are compared as predicted from the use of collision efficiencies computed using two different models to allow for droplet-droplet contact: one which considers slip flow effects only, and one which considers the combined effects of van der Waals forces and slip flow. The rate at which the droplet mass density function shifts to larger droplet sizes is increased by typically 20-25 percent, when collision efficiencies which include van der Waals forces are used.

Geautomatiseerde Verwerking van Militaire berichten Volgens ADatP-3 (Automated Processing of Military Messages According to ADatP-3)

DTIC Science & Technology

1992-06-01

ATCCIS beoogt juist dat te bereiken door te werken aan ecn informatie model en een data element dictionary. TNO-rapport Pagina 9 Binnen bet C2...en distributie 44 4.3.2 Interface met de gebruiker 45 4.3.3 Interface met dc operationcle database 46 TNO-rapport Pagina 11 4.3.3.1 Interpretatie...die bezig zijn met het ontwikkelen en implementeren van berichtformaten. Deel I van de publicatie bevat de beschrijving van FORMETS, delen 11 , I11 en

[Trait-aggression and suicide of Vincent van Gogh].

PubMed

Pezenhoffer, Ibolya; Gerevich, József

2015-01-01

Although in recent decades the literature has paid special attention to Vincent van Gogh's life, work and illness, there has still not been an examination of the connections between his trait aggression and his suicide. The present study traces, in the light of this trait aggression, the predictive factors that can be observed on the path leading to the artist's suicide. Biographical documents, case history data, as well as letters and the findings of earlier research have been used in the course of the analysis. Among the distal suicide risk factors we find a positive family anamnesis, childhood traumas (emotional deprivation, identity problems associated with the name Vincent), a vagrant, homeless way of life, failures in relationships with women, and psychotic episodes appearing in rushes. The proximal factors include the tragic friendship with Gauguin (frustrated love), his brother Theo's marriage (experienced as a loss), and a tendency to self-destruction. Both factor groups on the one hand determined the course of development of the trait aggression and on the other can also be regarded as a manifestation of that trait aggression. It can be said that the trait aggression played an important role in Van Gogh's suicide.

Assessment of narrow angles by gonioscopy, Van Herick method and anterior segment optical coherence tomography.

PubMed

Park, Seong Bae; Sung, Kyung Rim; Kang, Sung Yung; Jo, Jung Woo; Lee, Kyoung Sub; Kook, Michael S

2011-07-01

To evaluate anterior chamber (AC) angles using gonioscopy, Van Herick technique and anterior segment optical coherence tomography (AS-OCT). One hundred forty-eight consecutive subjects were enrolled. The agreement between any two of three diagnostic methods, gonioscopy, AS-OCT and Van Herick, was calculated in narrow-angle patients. The area under receiver-operating characteristic curves (AUC) for discriminating between narrow and open angles determined by gonioscopy was calculated in all participants for AS-OCT parameter angle opening distance (AOD), angle recess area, trabecular iris surface area and anterior chamber depth (ACD). As a subgroup analysis, capability of AS-OCT parameters for detecting angle closure defined by AS-OCT was assessed in narrow-angle patients. The agreement between the Van Herick method and gonioscopy in detecting angle closure was excellent in narrow angles (κ = 0.80, temporal; κ = 0.82, nasal). However, agreement between gonioscopy and AS-OCT and between the Van Herick method and AS-OCT was poor (κ = 0.11-0.16). Discrimination capability of AS-OCT parameters between open and narrow angles determined by gonioscopy was excellent for all AS-OCT parameters (AUC, temporal: AOD500 = 0.96, nasal: AOD500 = 0.99). The AUCs for detecting angle closure defined by AS-OCT image in narrow angle subjects was good for all AS-OCT parameters (AUC, 0.80-0.94) except for ACD (temporal: ACD = 0.70, nasal: ACD = 0.63). Assessment of narrow angles by gonioscopy and the Van Herick technique showed good agreement, but both measurements revealed poor agreement with AS-OCT. The angle closure detection capability of AS-OCT parameters was excellent; however, it was slightly lower in ACD.

[Elimination of all trans fatty acids].

PubMed

Katan, M B

2008-02-09

At the start of the 20th century, the production of trans fatty acids was originally largely driven by the increasing demand for margarine. The two Dutch margarine firms Van den Bergh and Jurgens played an important role in this early development. In the early 1990s it was shown that trans fatty acids increase the risk of heart disease. Unilever, the successor to Van den Bergh and Jurgens, then took the lead in eliminating trans fatty acids from retail foods worldwide. As a result, intake in The Netherlands fell from 15 g per day in 1980 to 3 g per day in 2003. Dairy products and meat are now the major source of trans fatty acids. The effects on health of these ruminant trans fatty acids are unclear. There are three lessons to be learned from the rise and fall of trans fatty acids. First, a history of safe use does not guarantee safety of food components, because routine surveillance will fail to detect adverse effects on common illnesses with long incubation periods. Second, it shows that it is more effective and easier to change the composition of foods than to change consumer behaviour. And third, governments can have a major impact on consumers' health by mandating the use of healthier food ingredients.

Spatial and temporal characterization of relativistic electron enhancements during the Van Allen Probes era.

NASA Astrophysics Data System (ADS)

Pinto, V. A.; Sibeck, D. G.; Moya, P. S.; Lyons, L. R.; Kanekal, S. G.; Kletzing, C.

2016-12-01

During the Van Allen probes era from September 2012 to June 2016 we have identified 53 relativistic electron enhancement events determined by increases to 2x103 #/sr-1}s{-1}cm^{-2 and above in the >2 MeV electron fluxes at geostationary orbit as measured by the GOES 13 and 15 Energetic Particle Sensor (EPS) instrument. Using the Van Allen Probes ECT-REPT and GOES EPS instruments we have characterized the radial and temporal profiles of the events, grouping them according to how the increases propagate radially. Using OMNI data we have studied the statistical properties of the solar wind for each group of events and have classified similarities and differences that might be relevant for each enhancement profile. We have also studied temporal and spatial wave activity (ULF and EMIC waves) using GOES magnetometer data and Van Allen Probes EMFISIS data for the different groups of events and categorized the appearance of such waves for the different enhancement profiles.

Uncovering Droop Control Laws Embedded Within the Nonlinear Dynamics of Van der Pol Oscillators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sinha, Mohit; Dorfler, Florian; Johnson, Brian B.

This paper examines the dynamics of power-electronic inverters in islanded microgrids that are controlled to emulate the dynamics of Van der Pol oscillators. The general strategy of controlling inverters to emulate the behavior of nonlinear oscillators presents a compelling time-domain alternative to ubiquitous droop control methods which presume the existence of a quasistationary sinusoidal steady state and operate on phasor quantities. We present two main results in this paper. First, by leveraging the method of periodic averaging, we demonstrate that droop laws are intrinsically embedded within a slower time scale in the nonlinear dynamics of Van der Pol oscillators. Second,more » we establish the global convergence of amplitude and phase dynamics in a resistive network interconnecting inverters controlled as Van der Pol oscillators. Furthermore, under a set of nonrestrictive decoupling approximations, we derive sufficient conditions for local exponential stability of desirable equilibria of the linearized amplitude and phase dynamics.« less

[Introduction].

PubMed

Gerard, Adrienne; van den Bogaard, Alberts

2008-01-01

Along with the international trends in history of computing, Dutch contributions over the past twenty years moved away from a focus on machinery to the broader scope of use of computers, appropriation of computing technologies in various traditions, labour relations and professionalisation issues, and, lately, software. It is only natural that an emerging field like computer science sets out to write its genealogy and canonise the important steps in its intellectual endeavour. It is fair to say that a historiography diverging from such "home" interest, started in 1987 with the work of Eda Kranakis--then active in The Netherlands--commissioned by the national bureau for technology assessment, and Gerard Alberts, turning a commemorative volume of the Mathematical Center into a history of the same institute. History of computing in The Netherlands made a major leap in the spring of 1994 when Dirk de Wit, Jan van den Ende and Ellen van Oost defended their dissertations, on the roads towards adoption of computing technology in banking, in science and engineering, and on the gender aspect in computing. Here, history of computing had already moved from machines to the use of computers. The three authors joined Gerard Alberts and Onno de Wit in preparing a volume on the rise of IT in The Netherlands, the sequel of which in now in preparation in a team lead by Adrienne van den Bogaard. Dutch research reflected the international attention for professionalisation issues (Ensmenger, Haigh) very early on in the dissertation by Ruud van Dael, Something to do with computers (2001) revealing how occupations dealing with computers typically escape the pattern of closure by professionalisation as expected by the, thus outdated, sociology of professions. History of computing not only takes use and users into consideration, but finally, as one may say, confronts the technological side of putting the machine to use, software, head on. The groundbreaking works of the 2000 Paderborn

Graphene Substrate for van der Waals Epitaxy of Layer-Structured Bismuth Antimony Telluride Thermoelectric Film.

PubMed

Kim, Eun Sung; Hwang, Jae-Yeol; Lee, Kyu Hyoung; Ohta, Hiromichi; Lee, Young Hee; Kim, Sung Wng

2017-02-01

Graphene as a substrate for the van der Waals epitaxy of 2D layered materials is utilized for the epitaxial growth of a layer-structured thermoelectric film. Van der Waals epitaxial Bi 0.5 Sb 1.5 Te 3 film on graphene synthesized via a simple and scalable fabrication method exhibits good crystallinity and high thermoelectric transport properties comparable to single crystals. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aqueous gating of van der Waals materials on bilayer nanopaper.

PubMed

Bao, Wenzhong; Fang, Zhiqiang; Wan, Jiayu; Dai, Jiaqi; Zhu, Hongli; Han, Xiaogang; Yang, Xiaofeng; Preston, Colin; Hu, Liangbing

2014-10-28

In this work, we report transistors made of van der Waals materials on a mesoporous paper with a smooth nanoscale surface. The aqueous transistor has a novel planar structure with source, drain, and gate electrodes on the same surface of the paper, while the mesoporous paper is used as an electrolyte reservoir. These transistors are enabled by an all-cellulose paper with nanofibrillated cellulose (NFC) on the top surface that leads to an excellent surface smoothness, while the rest of the microsized cellulose fibers can absorb electrolyte effectively. Based on two-dimensional van der Waals materials, including MoS2 and graphene, we demonstrate high-performance transistors with a large on-off ratio and low subthreshold swing. Such planar transistors with absorbed electrolyte gating can be used as sensors integrated with other components to form paper microfluidic systems. This study is significant for future paper-based electronics and biosensors.

Cosmology with an interacting van der Waals fluid

NASA Astrophysics Data System (ADS)

Elizalde, E.; Khurshudyan, M.

A model for the late-time accelerated expansion of the Universe is considered where a van der Waals fluid interacting with matter plays the role of dark energy. The transition towards this phase in the cosmic evolution history is discussed in detail and, moreover, a complete classification of the future finite-time singularities is obtained for six different possible forms of the nongravitational interaction between dark energy (the van der Waals fluid) and dark matter. This study shows, in particular, that a Universe with a noninteracting three-parameter van der Waals fluid can evolve into a Universe characterized by a type IV (generalized sudden) singularity. On the other hand, for certain values of the parameters, exit from the accelerated expanding phase is possible in the near future, what means that the expansion of the Universe in the future could become decelerated - to our knowledge, this interesting situation is not commonplace in the literature. On the other hand, our study shows that space can be divided into different regions. For some of them, in particular, the nongravitational interactions Q = 3Hbρde, Q = 3Hbρdm and Q = 3Hb(ρde + ρde) may completely suppress future finite-time singularity formation, for sufficiently high values of b. On the other hand, for some other regions of the parameter space, the mentioned interactions would not affect the singularity type, namely the type IV singularity generated in the case of the noninteracting model would be preserved. A similar conclusion has been archived for the cases of Q = 3bHρdeρdm/(ρde + ρdm), Q = 3bHρdm2/(ρ de + ρdm) and Q = 3bHρde2/(ρ de + ρdm) nongravitational interactions, with only one difference: the Q = 3bHρdm2/(ρ de + ρdm) interaction will change the type IV singularity of the noninteracting model into a type II (the sudden) singularity.

Van Swieten and the renaissance of the Vienna Medical School.

PubMed

Kidd, M; Modlin, I M

2001-04-01

The period until 1745 found the Viennese medical system languishing far behind advances made in other major European centers. This chaotic situation was reversed by the foresight and breadth of vision of the Empress Maria Theresa, who initiated considerable reform in Austria by actively recruiting the best minds of the time to reduce the intellectual and technologic differences. Her ability to entice one of Boerhaave's most eminent pupils, Gerard van Swieten, to leave Leiden for Vienna, particularly benefited the Vienna Medical School. In 1745 van Swieten assumed responsibility for reconfiguration of the patronage and nepotism-ridden medical system of the Austro-Hungarian Empire. As a first task, he swiftly expunged the influence of the Jesuits and other religious orders from medicine and established formal training and examinations, transforming the medical discipline into a meritocracy. Excelling as a physician and an innovative teacher, he also established a close personal relationship with the Empress and became her medical confidante. To a large part, the success of this first great Viennese medical school was owed to de Haen, who left Leiden to implement Boerhaave's method of clinical teaching. As a result of these innovations and with considerable support from the Empress, the University of Vienna, particularly its medical school, within a few decades achieved recognition throughout Europe as a seat of learning and scholarship. Van Swieten would not be remembered today if his contribution had been only scholarly or scientific achievements. He propelled Austrian medicine to a level commensurate with that of other European states of the day by 27 years of dedicated and industrious service.

DdlN from Vancomycin-Producing Amycolatopsis orientalis C329.2 Is a VanA Homologue with d-Alanyl-d-Lactate Ligase Activity

PubMed Central

Marshall, C. Gary; Wright, Gerard D.

1998-01-01

Vancomycin-resistant enterococci acquire high-level resistance to glycopeptide antibiotics through the synthesis of peptidoglycan terminating in d-alanyl-d-lactate. A key enzyme in this process is a d-alanyl-d-alanine ligase homologue, VanA or VanB, which preferentially catalyzes the synthesis of the depsipeptide d-alanyl-d-lactate. We report the overexpression, purification, and enzymatic characterization of DdlN, a VanA and VanB homologue encoded by a gene of the vancomycin-producing organism Amycolatopsis orientalis C329.2. Evaluation of kinetic parameters for the synthesis of peptides and depsipeptides revealed a close relationship between VanA and DdlN in that depsipeptide formation was kinetically preferred at physiologic pH; however, the DdlN enzyme demonstrated a narrower substrate specificity and commensurately increased affinity for d-lactate in the C-terminal position over VanA. The results of these functional experiments also reinforce the results of previous studies that demonstrated that glycopeptide resistance enzymes from glycopeptide-producing bacteria are potential sources of resistance enzymes in clinically relevant bacteria. PMID:9791137

Astronaut James van Hoften on RMS tracking Syncom IV-3 after deployment

NASA Image and Video Library

1985-09-01

51I-41-086 (1 September 1985) --- Astronaut James D. van Hoften, mission specialist, flexes his muscles in celebration of a triumphant extravehicular task. Clouds over the ocean form the backdrop for this 70mm scene, toward the end of a two-day effort to capture, repair and release the previously errant Syncom IV-3 communications satellite. Van Hoften, anchored to a special foot restraint device on the end of Discovery's Remote Manipulator System (RMS), had just performed the final "shove" that started the relative separation of the Shuttle and the Syncom, which is not far out of frame. He had been joined by astronaut William F. Fisher for the busy two days of EVA.

The Van Hiele geometry thinking levels of mild mental retardation students

NASA Astrophysics Data System (ADS)

Shomad, Z. A.; Kusmayadi, T. A.; Riyadi

2017-12-01

This research is to investigate the level of mild mental retardation geometry students thinking. This research focuses on the geometry thinking level based on Van Hiele theory. This study uses qualitative methods with case study strategy. Data obtained from observation and tests result. The subjects are 12 mental retardation students. The result show that ability of mild mental retardation students with each other is different but have same level of level thinking geometry. The geometry thinking level of mental retardation students was identified in level 1 of the Van Hiele theory. Based on the level thinking geometry of mental retardation students simplify geometry thinking teachers in selecting appropriate learning methods, choose the materials in accordance with ability, and can modify the material following the geometry thinking level of mental retardation students.

Mixed Dimensional Van der Waals Heterostructures for Opto-Electronics.

NASA Astrophysics Data System (ADS)

Jariwala, Deep

The isolation of a growing number of two-dimensional (2D) materials has inspired worldwide efforts to integrate distinct 2D materials into van der Waals (vdW) heterostructures. While a tremendous amount of research activity has occurred in assembling disparate 2D materials into ``all-2D'' van der Waals heterostructures, this concept is not limited to 2D materials alone. Given that any passivated, dangling bond-free surface will interact with another via vdW forces, the vdW heterostructure concept can be extended to include the integration of 2D materials with non-2D materials that adhere primarily through noncovalent interactions. In the first part of this talk I will present our work on emerging mixed-dimensional (2D + nD, where n is 0, 1 or 3) heterostructure devices performed at Northwestern University. I will present two distinct examples of gate-tunable p-n heterojunctions 1. Single layer n-type MoS2\\ (2D) combined with p-type semiconducting single walled carbon nanotubes (1D) and 2. Single layer MoS2 combined with 0D molecular semiconductor, pentacene. I will present the unique electrical properties, underlying charge transport mechanisms and photocurrent responses in both the above systems using a variety of scanning probe microscopy techniques as well as computational analysis. This work shows that van der Waals interactions are robust across different dimensionalities of materials and can allow fabrication of semiconductor devices with unique geometries and properties unforeseen in bulk semiconductors. Finally, I will briefly discuss our recent work from Caltech on near-unity absorption in atomically-thin photovoltaic devices. This work is supported by the Materials Research Center at Northwestern University, funded by the National Science Foundation (NSF DMR-1121262) and the Resnick Sustainability Institute at Caltech.

Mammograms on-the-go-predictors of repeat visits to mobile mammography vans in St Louis, Missouri, USA: a case-control study.

PubMed

Drake, Bettina F; Abadin, Salmafatima S; Lyons, Sarah; Chang, Su-Hsin; Steward, Lauren T; Kraenzle, Susan; Goodman, Melody S

2015-03-20

Among women, breast cancer is the most common non-cutaneous cancer and second most common cause of cancer-related death. The purpose of this study was to determine the extent to which women use mobile mammography vans for breast cancer screening and what factors are associated with repeat visits to these vans. A case-control study. Cases are women who had a repeat visit to the mammography van. (n=2134). Women who received a mammogram as part of Siteman Cancer Center's Breast Health Outreach Program responded to surveys and provided access to their clinical records (N=8450). Only visits from 2006 to 2014 to the mammography van were included. The main outcome is having a repeat visit to the mammography van. Among the participants, 25.3% (N=2134) had multiple visits to the mobile mammography van. Data were analysed using χ(2) tests, logistic regression and negative binomial regression. Women who were aged 50-65, uninsured, or African-American had higher odds of a repeat visit to the mobile mammography van compared with women who were aged 40-50, insured, or Caucasian (OR=1.135, 95% CI 1.013 to 1.271; OR=1.302, 95% CI 1.146 to 1.479; OR=1.281, 95% CI 1.125 to 1.457), respectively. However, the odds of having a repeat visit to the van were lower among women who reported a rural ZIP code or were unemployed compared with women who provided a suburban ZIP code or were employed (OR=0.503, 95% CI 0.411 to 0.616; OR=.868, 95% CI 0.774 to 0.972), respectively. This study has identified key characteristics of women who are either more or less likely to use mobile mammography vans as their primary source of medical care for breast cancer screening and have repeat visits. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Space Geoengineering: James A. Van Allen's Role in Detecting and Disrupting the Magnetosphere, 1958-1962 (Invited)

NASA Astrophysics Data System (ADS)

Fleming, J. R.

2010-12-01

James A. Van Allen’s celebrated discovery of Earth’s radiation belts in 1958 using Explorer 1 and 3 satellites was immediately followed by his agreement to monitor tests of nuclear weapons in space aimed at disrupting the magnetosphere. This is “space geoengineering” on a planetary scale. “Space is radioactive,” noted Van Allen’s colleague Eric Ray, and the military wanted to make it even more radioactive by nuclear detonations that, in time of war might disrupt enemy radio communications from half a world away and damage or destroy enemy intercontinental ballistic missiles. This study of Van Allen’s participation in Project Argus (1958) and Project Starfish (1962) is based on new posthumous accessions to the Van Allen Papers. At the time radio astronomers protested that, “No government has the right to change the environment in any significant way without prior international study and agreement.” Van Allen later regretted his participation in experiments that disrupted the natural magnetosphere. In a larger policy framework, the history of these space interventions and the protests they generated serve as a cautionary tale for today’s geoengineers who are proposing heavy-handed manipulation of the planetary environment as a response to future climate warming. Anyone claiming that geoengineering has not yet been attempted should be reminded of the planetary-scale engineering of these nukes in space. N. Christofilos describing the intended effect of the Argus nuclear explosions on the magnetosphere, which would direct a stream of radioactive particles along magnetic lines of force half a world away.

1. Photocopy of woodengraving by Van Vleck & Keith from ...

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

1. Photocopy of wood-engraving by Van Vleck & Keith from a photograph by Shireff of Higgins' Daguerrian Rooms, Sacramento, with figures, etc. touched up by Nahl & Brothers. Illustration from The Californian Farmer, July 4, 1862. STANFORD HOUSE BY SETH BABSON, VIEW FROM THE NORTHEAST - Leland Stanford House, 800 N Street, Sacramento, Sacramento County, CA

VanT, a Homologue of Vibrio harveyi LuxR, Regulates Serine, Metalloprotease, Pigment, and Biofilm Production in Vibrio anguillarum

PubMed Central

Croxatto, Antony; Chalker, Victoria J.; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L.

2002-01-01

Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum ΔvanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the ΔvanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an l-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum ΔvanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production. PMID:11872713

VanT, a homologue of Vibrio harveyi LuxR, regulates serine, metalloprotease, pigment, and biofilm production in Vibrio anguillarum.

PubMed

Croxatto, Antony; Chalker, Victoria J; Lauritz, Johan; Jass, Jana; Hardman, Andrea; Williams, Paul; Cámara, Miguel; Milton, Debra L

2002-03-01

Vibrio anguillarum possesses at least two N-acylhomoserine lactone (AHL) quorum-sensing circuits, one of which is related to the luxMN system of Vibrio harveyi. In this study, we have cloned an additional gene of this circuit, vanT, encoding a V. harveyi LuxR-like transcriptional regulator. A V. anguillarum Delta vanT null mutation resulted in a significant decrease in total protease activity due to loss of expression of the metalloprotease EmpA, but no changes in either AHL production or virulence. Additional genes positively regulated by VanT were identified from a plasmid-based gene library fused to a promoterless lacZ. Three lacZ fusions (serA::lacZ, hpdA-hgdA::lacZ, and sat-vps73::lacZ) were identified which exhibited decreased expression in the Delta vanT strain. SerA is similar to 3-phosphoglycerate dehydrogenases and catalyzes the first step in the serine-glycine biosynthesis pathway. HgdA has identity with homogentisate dioxygenases, and HpdA is homologous to 4-hydroxyphenylpyruvate dioxygenases (HPPDs) involved in pigment production. V. anguillarum strains require an active VanT to produce high levels of an L-tyrosine-induced brown color via HPPD, suggesting that VanT controls pigment production. Vps73 and Sat are related to Vibrio cholerae proteins encoded within a DNA locus required for biofilm formation. A V. anguillarum Delta vanT mutant and a mutant carrying a polar mutation in the sat-vps73 DNA locus were shown to produce defective biofilms. Hence, a new member of the V. harveyi LuxR transcriptional activator family has been characterized in V. anguillarum that positively regulates serine, metalloprotease, pigment, and biofilm production.

Proceedings Papers of the AFSC (Air Force Systems Command) Avionics Standardization Conference (2nd) Held at Dayton, Ohio on 30 November-2 December 1982. Volume 1.

DTIC Science & Technology

1982-11-01

Avionic Systems Integration Facilities, Mark van den Broek 1113 and Paul M. Vicen, AFLC/LOE Planning of Operational Software Implementation Tool...classified as software tools, including: * o" Operating System " Language Processors (compilers, assem’blers, link editors) o Source Editors " Debug Systems ...o Data Base Systems o Utilities o Etc . This talk addresses itself to the current set of tools provided JOVIAL iJ73 1750A application programmners by

Efficient Algorithms for Bayesian Network Parameter Learning from Incomplete Data

DTIC Science & Technology

2015-07-01

Efficient Algorithms for Bayesian Network Parameter Learning from Incomplete Data Guy Van den Broeck∗ and Karthika Mohan∗ and Arthur Choi and Adnan ...notwithstanding any other provision of law , no person shall be subject to a penalty for failing to comply with a collection of information if it does...Wasserman, L. (2011). All of Statistics. Springer Science & Business Media. Yaramakala, S., & Margaritis, D. (2005). Speculative markov blanket discovery for optimal feature selection. In Proceedings of ICDM.

Faint Photoelectric Photometric Standard Star Sequences

DTIC Science & Technology

1988-07-15

data awaiting additional study which will result in published research papers . The following list is a compilation of the publications which have...Astrophysical Journal, 323, 271, 1987. papers in preparation.... 1. "The Open Cluster van den Bergh Hagen-Harris No. 99", by A. U. Landolt, C. L...REPORT For a Grant for Basic Scientific Research (AFOSR Grant No. 82-0192) from The Air Force Office of Scientific Research entitled FAINT

Symposium on Animal Retroviruses: Abstracts. Held in Denver, Colorado on 10 December 1986

DTIC Science & Technology

1986-12-10

Ogilvie, M. B. Tompkins, W. A. F. Tompkins and S. Daniel, University of Illinois, Urbana, IL. 3:15 Coffee Break 3:45 MOLECULAR BIOLOGY OF BOVINE ...secretion, or by altering cell functions through cell surface receptors. MOLECULAR BIOLOGY OF BOVINE LEUKEMIA VIRUS. A. Burny, Y. Cleuter, R. Kettmann, M...Mammerickx, G. Marbaix, D. Portetelle, A. Van Den Broeke and L. Willems, University of Brussels, Rhode-Saint-Genese, Belgium. Bovine leukemia virus (BLV

Cytochrome c Gene and Protein Expression: Developmental Regulation, Environmental Response, and Pesticide Sensitivity in Aedes aegypti

DTIC Science & Technology

2008-05-01

biological systems. In the mosquito Aedes ae- gypti (L.), a primary vector of dengue and yellow fever viruses, the role of cytochrome c during devel...development of mosquitoes re- quiresmultigene regulation(Seversonet al. 2004,Fon- tenille et al. 2005,Raibaudet al. 2006, Strodeet al. 2006, van den...1.5% RH in an environ- mental chamber (L-C Incubator, Lab-Line Instru- ments, Inc., Melrose Park, IL) for the time course study. Sixty individuals (30

Geometrical study of phyllotactic patterns by Bernoulli spiral lattices.

PubMed