State Defense Force Monograph Series. Fall 2007, Special Units

DTIC Science & Technology

2007-01-01

authors and the visual panorama of artists and film makers. Those World War Two soldiers for whom “taps” has not yet been sounded may still remember the...Defense Force Monograph Series, Fall 2007, SPECIAL UNITS The Primary Zone will encompass the direct blast and thermal effects of the detonation and also...structural damage and the immediate fires from the thermal effects, although there may be secondary fires outside the Primary Zone. For a 10kt

Fire and bark beetle interactions

Treesearch

Ken Gibson; Jose F. Negron

2009-01-01

Bark beetle populations are at outbreak conditions in many parts of the western United States and causing extensive tree mortality. Bark beetles interact with other disturbance agents in forest ecosystems, one of the primary being fires. In order to implement appropriate post-fire management of fire-damaged ecosystems, we need a better understanding of...

Damage capitation in the modern liability climate: a primer for neurosurgeons and systematic review of the literature.

PubMed

Lepard, Jacob R; Walters, Beverly C; Rozzelle, Curtis J

2018-04-01

OBJECTIVE Neurosurgery, and particularly spine surgery, is among the most highly litigated medical specialties in the US, rendering the current malpractice climate of primary importance to spine surgeons nationwide. One of the primary methods of tort reform in the civil justice system is malpractice damage capitation (or "caps"); however, its efficacy is widely debated. The purpose of this article is to serve as a review for the practicing neurosurgeon, with particular emphasis on short- and long-term effects of damage caps and on the current debate regarding their utility, based on a systematic review of the literature. METHODS The Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines for systematic review of observational studies were used in the design of the study. Multiple medical and legal online databases (MEDLINE, Scopus, EMBASE, and JSTOR) were queried using the key words "malpractice" and "damage capitation" for articles from 2000 to 2014. A total of 96 abstracts were screened for inclusion and exclusion criteria. Of these, 22 articles were reviewed in full and another 15 were excluded for study design or poor quality of data. Five more studies were added after cross-checking the bibliographies of the included articles. The resulting 12 articles were evaluated; relevant data were extracted using a standardized metric. RESULTS Five studies were found showing varying effects of capitation on physician availability, with only 1 of these specifically showing increased availability of neurosurgery and elective spine coverage in states with capitation. Four studies demonstrated that capitation overall succeeds in decreasing jury awards and frequency of claims filed. Last, 3 studies were found showing an overall decrease in malpractice premiums for states that passed damage capitation. CONCLUSIONS There is evidence in the literature showing that total and noneconomic damage capitation has the potential to improve the practice environment for neurosurgeons nationwide. Additionally, there are other factors that affect malpractice premium rates, such as the investment markets, which are not affected by these laws. All of these are important for spine surgeons to consider and be aware of in advocating for appropriate reform measures in their states.

Information-theoretical noninvasive damage detection in bridge structures

NASA Astrophysics Data System (ADS)

Sudu Ambegedara, Amila; Sun, Jie; Janoyan, Kerop; Bollt, Erik

2016-11-01

Damage detection of mechanical structures such as bridges is an important research problem in civil engineering. Using spatially distributed sensor time series data collected from a recent experiment on a local bridge in Upper State New York, we study noninvasive damage detection using information-theoretical methods. Several findings are in order. First, the time series data, which represent accelerations measured at the sensors, more closely follow Laplace distribution than normal distribution, allowing us to develop parameter estimators for various information-theoretic measures such as entropy and mutual information. Second, as damage is introduced by the removal of bolts of the first diaphragm connection, the interaction between spatially nearby sensors as measured by mutual information becomes weaker, suggesting that the bridge is "loosened." Finally, using a proposed optimal mutual information interaction procedure to prune away indirect interactions, we found that the primary direction of interaction or influence aligns with the traffic direction on the bridge even after damaging the bridge.

Host plants of the tranished plant bug, Lygus Lineolaris (Palisot De Beauvois)

USDA-ARS?s Scientific Manuscript database

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is a highly polyphagous mirid that damages economically important plants across much of the new world including vegetables, fruits, nuts, nursery stock, and fiber. It is a primary pest of cotton across the mid-south of the United State...

Recent Developments of the Florida Public Hurricane Loss Model

NASA Astrophysics Data System (ADS)

Cocke, S.; Shin, D. W.; Annane, B.

2016-12-01

Catastrophe models are used extensively by the insurance industry to estimate losses due to natural hazards such as hurricanes and earthquakes. In the state of Florida, primary insurers for hurricane damage to residential properties are required by law to use certified catastrophe models to establish their premiums and capital reserves. The Florida Public Hurricane Loss Model (FPHLM) is one of only five certified catastrophe models in Florida, and the only non-commercial model certified. The FPHLM has been funded through the Florida Legislature and is overseen by the Florida Office of Insurance Regulation (OIR). The model was developed by a consortium of universities and private consultants primary located in Florida, but includes some partners outside of the state. The FPHLM has met Florida requirements since 2006 and has undergone continuous evolution to maintain state-of-the-art capabilities and changes in state requirements established by the Florida Commission on Hurricane Loss Projection Methodology. Recently the model has been undergoing major enhancement to incorporate damage due to flooding, which not only includes hurricane floods but floods due to all potential natural hazards. This work is being done in anticipation of future changes in the National Flood Insurance Program (NFIP) that will bring private insurers to the flood market. The model will incorporate a surge model as well as an inland flood model. We will present progress on these recent enhancements along with additional progress of the model.

Use of satellite image data to identify changes in hemlock health over space and time

Treesearch

Laurent R. Bonneau; Kathleen S. Shields; Daniel L. Civco; David R. Mikus

2000-01-01

Eastern hemlock (Tsuga canadensis (L.) Carriere), is an important component of ecosystems in the northeastern United States and is the primary coniferous species in southern Connecticut. Hemlocks play a unique role in the region by providing spatial and structural habitat diversity that supports many wildlife and fish populations. Widespread damage...

Importance of secondary damage in downer cows.

PubMed

Poulton, P J; Vizard, A L; Anderson, G A; Pyman, M F

2016-05-01

To investigate the relative importance in downer cows of the primary cause of recumbency in comparison with secondary complications. Downer dairy cows were monitored during their recumbency under field conditions in South Gippsland, Victoria, Australia. The cause of the original recumbency of the 218 cows was determined and secondary damage, status on day 7 and final outcome were recorded. Some type of secondary damage was found in 183/218 (84%) cows, of which 173/218 (79%) had damage deemed to be clinically important. By day 7, 52 (24%) had recovered and 69 (32%) eventually recovered. Of the 149 (68%) cows that were euthanased or died, 23 (15%) were deemed to have been lost solely from the primary cause, 107 (72%) from secondary damage and 19 (13%) from a combination of both. There was no difference in recovery among the five broad groups of causes of primary recumbency. Secondary damage was very common and presented in a large variety of ways, with many cows having multiple types of secondary damage concurrently. For most cows the secondary damage was more important than the initial primary damage in determining their fate. © 2016 Australian Veterinary Association.

Analysis of neutron spectrum effects on primary damage in tritium breeding blankets

NASA Astrophysics Data System (ADS)

Choi, Yong Hee; Joo, Han Gyu

2012-07-01

The effect of neutron spectrum on primary damages in a structural material of a tritium breeding blanket is investigated with a newly established recoil spectrum estimation system. First, a recoil spectrum generation code is developed to obtain the energy spectrum of primary knock-on atoms (PKAs) for a given neutron spectrum utilizing the latest ENDF/B data. Secondly, a method for approximating the high energy tail of the recoil spectrum is introduced to avoid expensive molecular dynamics calculations for high energy PKAs using the concept of recoil energy of the secondary knock-on atoms originated by the INtegration of CAScades (INCAS) model. Thirdly, the modified spectrum is combined with a set of molecular dynamics calculation results to estimate the primary damage parameters such as the number of surviving point defects. Finally, the neutron spectrum is varied by changing the material of the spectral shifter and the result in primary damage parameters is examined.

A comparison of neutron and gamma damage effects on silica glass in a nuclear reactor radiation environment

NASA Astrophysics Data System (ADS)

Holcomb, David E.; Miller, Don W.

1993-08-01

A study of the relative damage effects of neutrons and gamma rays on silica glass in a nuclear reactor radiation environment is reported. The neutron and gamma energy spectra of the Ohio State University Research Reactor beam port #1 were applied to silica glass to obtain primary knock-on charged particle energy spectra. The resultant charged particle spectra were then applied to the polyatomic forms of the Lindhard et al. integrodifferential equation for damage energy and the Parkin and Coulter integrodifferential equation for net atomic displacement. The results show that near a nuclear reactor core the vast majority of the dose to silica is due to gamma rays (factor of roughly 40) and that neutrons cause much more displacement damage than gamma rays (35 times the oxygen displacement rate and 500 times the silicon displacement rate). However, pure silica core optical fibers irradiated in a nuclear reactor's mixed neutron/gamma environment exhibit little difference in transmission loss on an equal dose basis compared to fibers irradiated in a gamma only environment, indicating that atomic displacement is not a significant damage mechanism.

White and gray matter damage in primary progressive MS

PubMed Central

Chard, Declan; Altmann, Daniel R.; Tozer, Daniel; Miller, David H.; Thompson, Alan J.; Wheeler-Kingshott, Claudia; Ciccarelli, Olga

2016-01-01

Objective: The temporal relationship between white matter (WM) and gray matter (GM) damage in vivo in early primary progressive multiple sclerosis (PPMS) was investigated testing 2 hypotheses: (1) WM tract abnormalities predict subsequent changes in the connected cortex (“primary WM damage model”); and (2) cortical abnormalities predict later changes in connected WM tracts (“primary GM damage model”). Methods: Forty-seven patients with early PPMS and 18 healthy controls had conventional and magnetization transfer imaging at baseline; a subgroup of 35 patients repeated the protocol after 2 years. Masks of the corticospinal tracts, genu of the corpus callosum and optic radiations, and of connected cortical regions, were used for extracting the mean magnetization transfer ratio (MTR). Multiple regressions within each of 5 tract-cortex pairs were performed, adjusting for the dependent variable's baseline MTR; tract lesion load and MTR, spinal cord area, age, and sex were examined for potential confounding. Results: The baseline MTR of most regions was lower in patients than in healthy controls. The tract-cortex pair relationships in the primary WM damage model were significant for the bilateral motor pair and right visual pair, while those in the primary GM damage model were only significant for the right motor pair. Lower lesion MTR at baseline was associated with lower MTR in the same tract normal-appearing WM at 2 years in 3 tracts. Conclusion: These results are consistent with the hypothesis that in early PPMS, cortical damage is for the most part a sequela of normal-appearing WM pathology, which, in turn, is predicted by abnormalities within WM lesions. PMID:26674332

White and gray matter damage in primary progressive MS: The chicken or the egg?

PubMed

Bodini, Benedetta; Chard, Declan; Altmann, Daniel R; Tozer, Daniel; Miller, David H; Thompson, Alan J; Wheeler-Kingshott, Claudia; Ciccarelli, Olga

2016-01-12

The temporal relationship between white matter (WM) and gray matter (GM) damage in vivo in early primary progressive multiple sclerosis (PPMS) was investigated testing 2 hypotheses: (1) WM tract abnormalities predict subsequent changes in the connected cortex ("primary WM damage model"); and (2) cortical abnormalities predict later changes in connected WM tracts ("primary GM damage model"). Forty-seven patients with early PPMS and 18 healthy controls had conventional and magnetization transfer imaging at baseline; a subgroup of 35 patients repeated the protocol after 2 years. Masks of the corticospinal tracts, genu of the corpus callosum and optic radiations, and of connected cortical regions, were used for extracting the mean magnetization transfer ratio (MTR). Multiple regressions within each of 5 tract-cortex pairs were performed, adjusting for the dependent variable's baseline MTR; tract lesion load and MTR, spinal cord area, age, and sex were examined for potential confounding. The baseline MTR of most regions was lower in patients than in healthy controls. The tract-cortex pair relationships in the primary WM damage model were significant for the bilateral motor pair and right visual pair, while those in the primary GM damage model were only significant for the right motor pair. Lower lesion MTR at baseline was associated with lower MTR in the same tract normal-appearing WM at 2 years in 3 tracts. These results are consistent with the hypothesis that in early PPMS, cortical damage is for the most part a sequela of normal-appearing WM pathology, which, in turn, is predicted by abnormalities within WM lesions. © 2015 American Academy of Neurology.

[Chest trauma: who, how and what?].

PubMed

Molnár, F Tamás

2012-10-01

A chest-trauma management system, tagged as the "Pécs model" in a tertiary referral center is described with extensive references to the state of the art in thoracic trauma. Chest drainage has utmost importance in primary therapy as well as in surgical decision making (diagnosis). Thoracotomy is a general surgical competence, just as damage control is. Definitive treatment and management of sequelae, however, requires competence in thoracic surgery. Multidisciplinarity is underscored.

[Comatose states: etiopathogenesis, experimental studies, treatment of hepatic coma].

PubMed

Strekalova, O S; Uchaĭkin, V F; Ipatova, O M; Torkhovskaia, T I; Medvedeva, N V; Storozhakov, G I; Archakov, A I

2009-01-01

The review presents the modern concepts on biochemical mechanisms of processes, that result in comatose states (CS), with emphasis on the search of new therapeutic approaches. CS of various origin causes severe suppression of brain cells functioning and stable unconsciousness. Numerous reasons of various CS are classified into two main groups: primary brain damages (ischemia, tumor, trauma) and secondary damages originating from system injuries in the body (endocrine, toxic e. c.). The most often primary CS is the hypoxic-ischemic one, as result of corresponding encephalopathy. Its mechanism is the brain cells "energy crisis"--because of decreased blood supply or its deficiency by energy substrates or/and by oxygen. Among secondary CS the substantial place takes hepatic coma as a consequence of hepatic encephalopathy in severe liver diseases--cirrhosis, acute liver failure, sharp intoxication. Its main reason is associated with exess of ammonia entering the brain tissue (it accumulates in blood because of lack of its removing by damaged hepatocytes). Ammonia reacts with glutamate in brain astrocytes and the product of this reaction, glutamine, induced osmotic imbalance, that results in change of form and functions of these important brain cells. It induces, in turn, neurons functions damages, changes in neurotransmission and cerebral blood flow and all these may give rise CS. The most of CS studies are carried out in human. Experimental models ofhepatic CS are reproduced mainly in rats, the most often by surgery methods. Other models included administration of thioacetamide or D-galactosamine, sometimes in combination with lipopolysaccharide. In earlier studies ammonia administration together with liver damages by ligation or by CCl4 was used. The main principles of hepatic coma treatment include the care of encephalopathy, detoxification, and liver treatment. Elaboration of new nanodrugs with increased penetration into tissues and cells, in particular, on the base of phospholipid nanoparticles, may increase substantially the therapeuti efficiency. One of such drug is thought to be a new hepatoprotective preparation phosphogliv--nanoparticles of soy phosphatidylcholine with glycyrrhizic acid. It is supposed, that the further development of phospholipid nanoforms, with minimal particle sizes, may reveal the more action in CS treatment.

Sterigmatocystin induces G1 arrest in primary human esophageal epithelial cells but induces G2 arrest in immortalized cells: key mechanistic differences in these two models.

PubMed

Wang, Juan; Huang, Shujuan; Xing, Lingxiao; Cui, Jinfeng; Tian, Ziqiang; Shen, Haitao; Jiang, Xiujuan; Yan, Xia; Wang, Junling; Zhang, Xianghong

2015-11-01

Sterigmatocystin (ST), a mycotoxin commonly found in food and feed commodities, has been classified as a "possible human carcinogen." Our previous studies suggested that ST exposure might be a risk factor for esophageal cancer and that ST may induce DNA damage and G2 phase arrest in immortalized human esophageal epithelial cells (Het-1A). To further confirm and explore the cellular responses of ST in human esophageal epithelia, we comparatively evaluated DNA damage, cell cycle distribution and the relative mechanisms in primary cultured human esophageal epithelial cells (EPC), which represent a more representative model of the in vivo state, and Het-1A cells. In this study, we found that ST could induce DNA damage in both EPC and Het-1A cells but led to G1 phase arrest in EPC cells and G2 phase arrest in Het-1A cells. Furthermore, our results indicated that the activation of the ATM-Chk2 pathway was involved in ST-induced G1 phase arrest in EPC cells, whereas the p53-p21 pathway activation in ST-induced G2 phase arrest in Het-1A cells. Studies have demonstrated that SV40 large T-antigen (SV40LT) may disturb cell cycle progression by inactivating some of the proteins involved in the G1/S checkpoint. Het-1A is a non-cancerous epithelial cell line immortalized by SV40LT. To evaluate the possible perturbation effect of SV40LT on ST-induced cell cycle disturbance in Het-1A cells, we knocked down SV40LT of Het-1A cells with siRNA and found that under this condition, ST-induced G2 arrest was significantly attenuated, whereas the proportion of cells in the G1 phase was significantly increased. Furthermore, SV40LT-siRNA also inhibited the activation of the p53-p21 signaling pathway induced by ST. In conclusion, our data indicated that ST could induce DNA damage in both primary cultured and immortalized esophageal epithelial cells. In primary human esophageal epithelial cells, ST induced DNA damage and then triggered the ATM-Chk2 pathway, resulting in G1 phase arrest, whereas in SV40LT-immortalized human esophageal epithelial cells, SV40LT-mediated G1 checkpoint inactivation occurred, and ST-DNA damage activated p53-p21 signaling pathway, up-regulating G2/M phase regulatory proteins and finally leading to a G2 phase arrest. Thus, the SV40LT-mediated G1 checkpoint inactivation is responsible for the difference in the cell cycle arrest by ST between immortalized and primary cultured human esophageal epithelial cells.

49 CFR 198.37 - State one-call damage prevention program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false State one-call damage prevention program. 198.37... REGULATIONS FOR GRANTS TO AID STATE PIPELINE SAFETY PROGRAMS Adoption of One-Call Damage Prevention Program § 198.37 State one-call damage prevention program. A State must adopt a one-call damage prevention...

GPS-Based Excavation Encroachment Notification

DOT National Transportation Integrated Search

2011-10-31

Excavation damage is the primary threat to the integrity of the natural gas distribution system. According to the Common Ground Alliance, the two primary root causes of excavation damage are failure to notify the one-call center and careless excavati...

Genotoxic and clastogenic effects of monohaloacetic acid drinking water disinfection by-products in primary human lymphocytes.

PubMed

Escobar-Hoyos, Luisa F; Hoyos-Giraldo, Luz Stella; Londoño-Velasco, Elizabeth; Reyes-Carvajal, Ingrid; Saavedra-Trujillo, Diana; Carvajal-Varona, Silvio; Sánchez-Gómez, Adalberto; Wagner, Elizabeth D; Plewa, Michael J

2013-06-15

The haloacetic acids (HAAs) are the second-most prevalent class of drinking water disinfection by-products formed by chemical disinfectants. Previous studies have determined DNA damage and repair of HAA-induced lesions in mammalian and human cell lines; however, little is known of the genomic DNA and chromosome damage induced by these compounds in primary human cells. The aim of this study was to evaluate the genotoxic and clastogenic effects of the monoHAA disinfection by-products in primary human lymphocytes. All monoHAAs were genotoxic in primary human lymphocytes, the rank order of genotoxicity and cytotoxicity was IAA > BAA > CAA. After 6 h of repair time, only 50% of the DNA damage (maximum decrease in DNA damage) was repaired compared to the control. This demonstrates that primary human lymphocytes are less efficient in repairing the induced damage by monoHAAs than previous studies with mammalian cell lines. In addition, the monoHAAs induced an increase in the chromosome aberration frequency as a measurement of the clastogenic effect of these compounds. These results coupled with genomic technologies in primary human cells and other mammalian non-cancerous cell lines may lead to the identification of biomarkers that may be employed in feedback loops to aid water chemists and engineers in the overall goal of producing safer drinking water. Copyright © 2013 Elsevier Ltd. All rights reserved.

Risk Factors and Predictors of Significant Chondral Surface Change From Primary to Revision Anterior Cruciate Ligament Reconstruction: A MOON and MARS Cohort Study.

PubMed

Magnussen, Robert A; Borchers, James R; Pedroza, Angela D; Huston, Laura J; Haas, Amanda K; Spindler, Kurt P; Wright, Rick W; Kaeding, Christopher C; Allen, Christina R; Anderson, Allen F; Cooper, Daniel E; DeBerardino, Thomas M; Dunn, Warren R; Lantz, Brett A; Mann, Barton; Stuart, Michael J; Albright, John P; Amendola, Annunziato; Andrish, Jack T; Annunziata, Christopher C; Arciero, Robert A; Bach, Bernard R; Baker, Champ L; Bartolozzi, Arthur R; Baumgarten, Keith M; Bechler, Jeffery R; Berg, Jeffrey H; Bernas, Geoffrey A; Brockmeier, Stephen F; Brophy, Robert H; Bush-Joseph, Charles A; Butler, J Brad; Campbell, John D; Carey, James L; Carpenter, James E; Cole, Brian J; Cooper, Jonathan M; Cox, Charles L; Creighton, R Alexander; Dahm, Diane L; David, Tal S; Flanigan, David C; Frederick, Robert W; Ganley, Theodore J; Garofoli, Elizabeth A; Gatt, Charles J; Gecha, Steven R; Giffin, James Robert; Hame, Sharon L; Hannafin, Jo A; Harner, Christopher D; Harris, Norman Lindsay; Hechtman, Keith S; Hershman, Elliott B; Hoellrich, Rudolf G; Hosea, Timothy M; Johnson, David C; Johnson, Timothy S; Jones, Morgan H; Kamath, Ganesh V; Klootwyk, Thomas E; Levy, Bruce A; Ma, C Benjamin; Maiers, G Peter; Marx, Robert G; Matava, Matthew J; Mathien, Gregory M; McAllister, David R; McCarty, Eric C; McCormack, Robert G; Miller, Bruce S; Nissen, Carl W; O'Neill, Daniel F; Owens, Brett D; Parker, Richard D; Purnell, Mark L; Ramappa, Arun J; Rauh, Michael A; Rettig, Arthur C; Sekiya, Jon K; Shea, Kevin G; Sherman, Orrin H; Slauterbeck, James R; Smith, Matthew V; Spang, Jeffrey T; Svoboda, Steven J; Taft, Timothy N; Tenuta, Joachim J; Tingstad, Edwin M; Vidal, Armando F; Viskontas, Darius G; White, Richard A; Williams, James S; Wolcott, Michelle L; Wolf, Brian R; York, James J

2018-03-01

Articular cartilage health is an important issue following anterior cruciate ligament (ACL) injury and primary ACL reconstruction. Factors present at the time of primary ACL reconstruction may influence the subsequent progression of articular cartilage damage. Larger meniscus resection at primary ACL reconstruction, increased patient age, and increased body mass index (BMI) are associated with increased odds of worsened articular cartilage damage at the time of revision ACL reconstruction. Case-control study; Level of evidence, 3. Subjects who had primary and revision data in the databases of the Multicenter Orthopaedics Outcomes Network (MOON) and Multicenter ACL Revision Study (MARS) were included. Reviewed data included chondral surface status at the time of primary and revision surgery, meniscus status at the time of primary reconstruction, primary reconstruction graft type, time from primary to revision ACL surgery, as well as demographics and Marx activity score at the time of revision. Significant progression of articular cartilage damage was defined in each compartment according to progression on the modified Outerbridge scale (increase ≥1 grade) or >25% enlargement in any area of damage. Logistic regression identified predictors of significant chondral surface change in each compartment from primary to revision surgery. A total of 134 patients were included, with a median age of 19.5 years at revision surgery. Progression of articular cartilage damage was noted in 34 patients (25.4%) in the lateral compartment, 32 (23.9%) in the medial compartment, and 31 (23.1%) in the patellofemoral compartment. For the lateral compartment, patients who had >33% of the lateral meniscus excised at primary reconstruction had 16.9-times greater odds of progression of articular cartilage injury than those with an intact lateral meniscus ( P < .001). For the medial compartment, patients who had <33% of the medial meniscus excised at the time of the primary reconstruction had 4.8-times greater odds of progression of articular cartilage injury than those with an intact medial meniscus ( P = .02). Odds of significant chondral surface change increased by 5% in the lateral compartment and 6% in the medial compartment for each increased year of age ( P ≤ .02). For the patellofemoral compartment, the use of allograft in primary reconstruction was associated with a 15-fold increased odds of progression of articular cartilage damage relative to a patellar tendon autograft ( P < .001). Each 1-unit increase in BMI at the time of revision surgery was associated with a 10% increase in the odds of progression of articular cartilage damage ( P = .046) in the patellofemoral compartment. Excision of the medial and lateral meniscus at primary ACL reconstruction increases the odds of articular cartilage damage in the corresponding compartment at the time of revision ACL reconstruction. Increased age is a risk factor for deterioration of articular cartilage in both tibiofemoral compartments, while increased BMI and the use of allograft for primary ACL reconstruction are associated with an increased risk of progression in the patellofemoral compartment.

BMAL1 and CLOCK proteins in regulating UVB-induced apoptosis and DNA damage responses in human keratinocytes.

PubMed

Sun, Yang; Wang, Peiling; Li, Hongyu; Dai, Jun

2018-06-26

A diverse array of biological processes are under circadian controls. In mouse skin, ultraviolet ray (UVR)-induced apoptosis and DNA damage responses are time-of-day dependent, which are controlled by core clock proteins. This study investigates the roles of clock proteins in regulating UVB responses in human keratinocytes (HKCs). We found that the messenger RNA expression of brain and muscle ARNT-like 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK) genes is altered by low doses (5 mJ/cm 2 ) of UVB in the immortalized HaCat HKCs cell line. Although depletion of BMAL1 or CLOCK has no effect on the activation of Rad3-related protein kinases-checkpoint kinase 1-p53 mediated DNA damage checkpoints, it leads to suppression of UVB-stimulated apoptotic responses, and downregulation of UVB-elevated expression of DNA damage marker γ-H2AX and cell cycle inhibitor p21. Diminished apoptotic responses are also observed in primary HKCs depleted of BMAL1 or CLOCK after UVB irradiation. While CLOCK depletion shows a suppressive effect on UVB-induced p53 protein accumulation, depletion of either clock gene triggers early keratinocyte differentiation of HKCs at their steady state. These results suggest that UVB-induced apoptosis and DNA damage responses are controlled by clock proteins, but via different mechanisms in the immortalized human adult low calcium temperature and primary HKCs. Given the implication of UVB in photoaging and photocarcinogenesis, mechanistic elucidation of circadian controls on UVB effects in human skin will be critical and beneficial for prevention and treatment of skin cancers and other skin-related diseases. © 2018 Wiley Periodicals, Inc.

Using risk-based analysis and geographic information systems to assess flooding problems in an urban watershed in Rhode Island.

PubMed

Hardmeyer, Kent; Spencer, Michael A

2007-04-01

This article provides an overview of the use of risk-based analysis (RBA) in flood damage assessment, and it illustrates the use of Geographic Information Systems (GIS) in identifying flood-prone areas, which can aid in flood-mitigation planning assistance. We use RBA to calculate expected annual flood damages in an urban watershed in the state of Rhode Island, USA. The method accounts for the uncertainty in the three primary relationships used in computing flood damage: (1) the probability that a given flood will produce a given amount of floodwater, (2) the probability that a given amount of floodwater will reach a certain stage or height, and (3) the probability that a certain stage of floodwater will produce a given amount of damage. A greater than 50% increase in expected annual flood damage is estimated for the future if previous development patterns continue and flood-mitigation measures are not taken. GIS is then used to create a map that shows where and how often floods might occur in the future, which can help (1) identify priority areas for flood-mitigation planning assistance and (2) disseminate information to public officials and other decision-makers.

Characterizing single isolated radiation-damage events from molecular dynamics via virtual diffraction methods

DOE PAGES

Stewart, James A.; Brookman, G.; Price, Patrick Michael; ...

2018-04-25

In this study, the evolution and characterization of single-isolated-ion-strikes are investigated by combining atomistic simulations with selected-area electron diffraction (SAED) patterns generated from these simulations. Five molecular dynamics simulations are performed for a single 20 keV primary knock-on atom in bulk crystalline Si. The resulting cascade damage is characterized in two complementary ways. First, the individual cascade events are conventionally quantified through the evolution of the number of defects and the atomic (volumetric) strain associated with these defect structures. These results show that (i) the radiation damage produced is consistent with the Norgett, Robinson, and Torrens model of damage productionmore » and (ii) there is a net positive volumetric strain associated with the cascade structures. Second, virtual SAED patterns are generated for the resulting cascade-damaged structures along several zone axes. The analysis of the corresponding diffraction patterns shows the SAED spots approximately doubling in size, on average, due to broadening induced by the defect structures. Furthermore, the SAED spots are observed to exhibit an average radial outward shift between 0.33% and 0.87% depending on the zone axis. Finally, this characterization approach, as utilized here, is a preliminary investigation in developing methodologies and opportunities to link experimental observations with atomistic simulations to elucidate microstructural damage states.« less

Characterizing single isolated radiation-damage events from molecular dynamics via virtual diffraction methods

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

Stewart, James A.; Brookman, G.; Price, Patrick Michael

In this study, the evolution and characterization of single-isolated-ion-strikes are investigated by combining atomistic simulations with selected-area electron diffraction (SAED) patterns generated from these simulations. Five molecular dynamics simulations are performed for a single 20 keV primary knock-on atom in bulk crystalline Si. The resulting cascade damage is characterized in two complementary ways. First, the individual cascade events are conventionally quantified through the evolution of the number of defects and the atomic (volumetric) strain associated with these defect structures. These results show that (i) the radiation damage produced is consistent with the Norgett, Robinson, and Torrens model of damage productionmore » and (ii) there is a net positive volumetric strain associated with the cascade structures. Second, virtual SAED patterns are generated for the resulting cascade-damaged structures along several zone axes. The analysis of the corresponding diffraction patterns shows the SAED spots approximately doubling in size, on average, due to broadening induced by the defect structures. Furthermore, the SAED spots are observed to exhibit an average radial outward shift between 0.33% and 0.87% depending on the zone axis. Finally, this characterization approach, as utilized here, is a preliminary investigation in developing methodologies and opportunities to link experimental observations with atomistic simulations to elucidate microstructural damage states.« less

Characterizing single isolated radiation-damage events from molecular dynamics via virtual diffraction methods

NASA Astrophysics Data System (ADS)

Stewart, J. A.; Brookman, G.; Price, P.; Franco, M.; Ji, W.; Hattar, K.; Dingreville, R.

2018-04-01

The evolution and characterization of single-isolated-ion-strikes are investigated by combining atomistic simulations with selected-area electron diffraction (SAED) patterns generated from these simulations. Five molecular dynamics simulations are performed for a single 20 keV primary knock-on atom in bulk crystalline Si. The resulting cascade damage is characterized in two complementary ways. First, the individual cascade events are conventionally quantified through the evolution of the number of defects and the atomic (volumetric) strain associated with these defect structures. These results show that (i) the radiation damage produced is consistent with the Norgett, Robinson, and Torrens model of damage production and (ii) there is a net positive volumetric strain associated with the cascade structures. Second, virtual SAED patterns are generated for the resulting cascade-damaged structures along several zone axes. The analysis of the corresponding diffraction patterns shows the SAED spots approximately doubling in size, on average, due to broadening induced by the defect structures. Furthermore, the SAED spots are observed to exhibit an average radial outward shift between 0.33% and 0.87% depending on the zone axis. This characterization approach, as utilized here, is a preliminary investigation in developing methodologies and opportunities to link experimental observations with atomistic simulations to elucidate microstructural damage states.

Written Language Impairments in Primary Progressive Aphasia: A Reflection of Damage to Central Semantic and Phonological Processes

ERIC Educational Resources Information Center

Henry, Maya L.; Beeson, Pelagie M.; Alexander, Gene E.; Rapcsak, Steven Z.

2012-01-01

Connectionist theories of language propose that written language deficits arise as a result of damage to semantic and phonological systems that also support spoken language production and comprehension, a view referred to as the "primary systems" hypothesis. The objective of the current study was to evaluate the primary systems account in a mixed…

Investigation on the correlation between energy deposition and clustered DNA damage induced by low-energy electrons.

PubMed

Liu, Wei; Tan, Zhenyu; Zhang, Liming; Champion, Christophe

2018-05-01

This study presents the correlation between energy deposition and clustered DNA damage, based on a Monte Carlo simulation of the spectrum of direct DNA damage induced by low-energy electrons including the dissociative electron attachment. Clustered DNA damage is classified as simple and complex in terms of the combination of single-strand breaks (SSBs) or double-strand breaks (DSBs) and adjacent base damage (BD). The results show that the energy depositions associated with about 90% of total clustered DNA damage are below 150 eV. The simple clustered DNA damage, which is constituted of the combination of SSBs and adjacent BD, is dominant, accounting for 90% of all clustered DNA damage, and the spectra of the energy depositions correlating with them are similar for different primary energies. One type of simple clustered DNA damage is the combination of a SSB and 1-5 BD, which is denoted as SSB + BD. The average contribution of SSB + BD to total simple clustered DNA damage reaches up to about 84% for the considered primary energies. In all forms of SSB + BD, the SSB + BD including only one base damage is dominant (above 80%). In addition, for the considered primary energies, there is no obvious difference between the average energy depositions for a fixed complexity of SSB + BD determined by the number of base damage, but average energy depositions increase with the complexity of SSB + BD. In the complex clustered DNA damage constituted by the combination of DSBs and BD around them, a relatively simple type is a DSB combining adjacent BD, marked as DSB + BD, and it is of substantial contribution (on average up to about 82%). The spectrum of DSB + BD is given mainly by the DSB in combination with different numbers of base damage, from 1 to 5. For the considered primary energies, the DSB combined with only one base damage contributes about 83% of total DSB + BD, and the average energy deposition is about 106 eV. However, the energy deposition increases with the complexity of clustered DNA damage, and therefore, the clustered DNA damage with high complexity still needs to be considered in the study of radiation biological effects, in spite of their small contributions to all clustered DNA damage.

Free energy profiles for two ubiquitous damaging agents: methylation and hydroxylation of guanine in B-DNA.

PubMed

Grüber, R; Aranda, J; Bellili, A; Tuñón, I; Dumont, E

2017-06-07

DNA methylation and hydroxylation are two ubiquitous reactions in DNA damage induction, yet insights are scarce concerning the free energy of activation within B-DNA. We resort to multiscale simulations to investigate the attack of a hydroxyl radical and of the primary diazonium onto a guanine embedded in a solvated dodecamer. Reaction free energy profiles characterize two strongly exergonic processes, yet allow unprecedented quantification of the barrier towards this damage reaction, not higher than 6 kcal mol -1 and sometimes inexistent, and of the exergonicities. In the case of the [G(C8)-OH]˙ intermediate, we challenge the functional dependence of such simulations: recently-proposed functionals, such as M06-2X and LC-BLYP, agree on a ∼4 kcal mol -1 barrier, whereas the hybrid GGA B3LYP functional predicts a barrier-less pathway. In the long term, multiscale approaches can help build up a unified panorama of DNA lesion induction. These results stress the importance of DFT/MM-MD simulations involving new functionals towards the sound modelling of biomolecule damage even in the ground state.

Predictability of state-level flood damage in the conterminous United States: the role of hazard, exposure and vulnerability

DOE PAGES

Zhou, Qianqian; Leng, Guoyong; Feng, Leyang

2017-07-13

Understanding historical changes in flood damage and the underlying mechanisms is critical for predicting future changes for better adaptations. In this study, a detailed assessment of flood damage for 1950–1999 is conducted at the state level in the conterminous United States (CONUS). Geospatial datasets on possible influencing factors are then developed by synthesizing natural hazards, population, wealth, cropland and urban area to explore the relations with flood damage. A considerable increase in flood damage in CONUS is recorded for the study period which is well correlated with hazards. Comparably, runoff indexed hazards simulated by the Variable Infiltration Capacity (VIC) modelmore » can explain a larger portion of flood damage variations than precipitation in 84% of the states. Cropland is identified as an important factor contributing to increased flood damage in central US while urbanland exhibits positive and negative relations with total flood damage and damage per unit wealth in 20 and 16 states, respectively. Altogether, flood damage in 34 out of 48 investigated states can be predicted at the 90% confidence level. In extreme cases, ~76% of flood damage variations can be explained in some states, highlighting the potential of future flood damage prediction based on climate change and socioeconomic scenarios.« less

Predictability of state-level flood damage in the conterminous United States: the role of hazard, exposure and vulnerability

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

Zhou, Qianqian; Leng, Guoyong; Feng, Leyang

Understanding historical changes in flood damage and the underlying mechanisms is critical for predicting future changes for better adaptations. In this study, a detailed assessment of flood damage for 1950–1999 is conducted at the state level in the conterminous United States (CONUS). Geospatial datasets on possible influencing factors are then developed by synthesizing natural hazards, population, wealth, cropland and urban area to explore the relations with flood damage. A considerable increase in flood damage in CONUS is recorded for the study period which is well correlated with hazards. Comparably, runoff indexed hazards simulated by the Variable Infiltration Capacity (VIC) modelmore » can explain a larger portion of flood damage variations than precipitation in 84% of the states. Cropland is identified as an important factor contributing to increased flood damage in central US while urbanland exhibits positive and negative relations with total flood damage and damage per unit wealth in 20 and 16 states, respectively. Altogether, flood damage in 34 out of 48 investigated states can be predicted at the 90% confidence level. In extreme cases, ~76% of flood damage variations can be explained in some states, highlighting the potential of future flood damage prediction based on climate change and socioeconomic scenarios.« less

Postradiation atrophy of mature bone

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

Ergun, H.; Howland, W.J.

1980-01-01

The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographic evidence of atrophy, localized osteopenia, is late in appearing. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. The differentiationmore » of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.« less

Space Shuttle Solid Rocket Booster Debris Assessment

NASA Technical Reports Server (NTRS)

Kendall, Kristin; Kanner, Howard; Yu, Weiping

2006-01-01

The Space Shuttle Columbia Accident revealed a fundamental problem of the Space Shuttle Program regarding debris. Prior to the tragedy, the Space Shuttle requirement stated that no debris should be liberated that would jeopardize the flight crew and/or mission success. When the accident investigation determined that a large piece of foam debris was the primary cause of the loss of the shuttle and crew, it became apparent that the risk and scope of - damage that could be caused by certain types of debris, especially - ice and foam, were not fully understood. There was no clear understanding of the materials that could become debris, the path the debris might take during flight, the structures the debris might impact or the damage the impact might cause. In addition to supporting the primary NASA and USA goal of returning the Space Shuttle to flight by understanding the SRB debris environment and capability to withstand that environment, the SRB debris assessment project was divided into four primary tasks that were required to be completed to support the RTF goal. These tasks were (1) debris environment definition, (2) impact testing, (3) model correlation and (4) hardware evaluation. Additionally, the project aligned with USA's corporate goals of safety, customer satisfaction, professional development and fiscal accountability.

Multifocal electroretinogram (MFERG) evaluation of laser-induced secondary damage in the non-human primate (NHP)

NASA Astrophysics Data System (ADS)

Zwick, Harry; Stuck, Bruce E.; Akers, A.; Edsall, Peter; DiCarlo, Cheryl D.; Lund, David J.

2005-04-01

Laser induced retinal damage may involve primary injury to the central retina and secondary damage, including intraretinal scar formation (IRSF) retinal traction (RT) and retinal nerve fiber layer injury (RNFL). We have evaluated these laser induced retinal pathologies with MFERG in non-human primates (NHPs) with a Veris (4.9) MFERG system 103 Hexagons, centered on the macula with non-scaled arrays and in one NHP with a 2-frame/M-step sequence to assess long term exposure effects within the RNFL. Chemical restraint was achieved using Ketamine stability HCL (10 mg/kg IM) and Propofol (0.5 mg-1.2/Kg/min via syringe pump). Peribulbar eye blocks were performed using 2% lidocain or a mixture of 2% Lidocain/Marcain (monitored ocular motility was less than 40 microns in retinal space). Primary and secondary damage effects were induced with either q-switched single pulse Neodymium (1064 nm, 1.0 mJ) or Argon CW (10 to 1000 msec, 10-150 mW). MFERG demonstrated capability to detect primary and secondary induced retinal damage in both 1st and 2nd order kernels. Primary and secondary damage in the central retina was often suppressed in amplitude and with longer latencies relative to the MFERG norm. Preliminary investigations in one NHP with Primary and secondary RNFL damage at 9 to 14 months showed recovery with non-scaled array one frame / M-step sequence but demonstrated significant abnormalities for a two frame/ M-step sequence. Utilization of advanced Veris recording parameters involving spatial and temporal manipulation of the stimulus parameters can improve detection of functional deficits induced by focal laser retinal injury.

Anatomical manifestations of primary blast ocular trauma observed in a postmortem porcine model.

PubMed

Sherwood, Daniel; Sponsel, William E; Lund, Brian J; Gray, Walt; Watson, Richard; Groth, Sylvia L; Thoe, Kimberly; Glickman, Randolph D; Reilly, Matthew A

2014-02-24

We qualitatively describe the anatomic features of primary blast ocular injury observed using a postmortem porcine eye model. Porcine eyes were exposed to various levels of blast energy to determine the optimal conditions for future testing. We studied 53 enucleated porcine eyes: 13 controls and 40 exposed to a range of primary blast energy levels. Eyes were preassessed with B-scan and ultrasound biomicroscopy (UBM) ultrasonography, photographed, mounted in gelatin within acrylic orbits, and monitored with high-speed videography during blast-tube impulse exposure. Postimpact photography, ultrasonography, and histopathology were performed, and ocular damage was assessed. Evidence for primary blast injury was obtained. While some of the same damage was observed in the control eyes, the incidence and severity of this damage in exposed eyes increased with impulse and peak pressure, suggesting that primary blast exacerbated these injuries. Common findings included angle recession, internal scleral delamination, cyclodialysis, peripheral chorioretinal detachments, and radial peripapillary retinal detachments. No full-thickness openings of the eyewall were observed in any of the eyes tested. Scleral damage demonstrated the strongest associative tendency for increasing likelihood of injury with increased overpressure. These data provide evidence that primary blast alone (in the absence of particle impact) can produce clinically relevant ocular damage in a postmortem model. The blast parameters derived from this study are being used currently in an in vivo model. We also propose a new Cumulative Injury Score indicating the clinical relevance of observed injuries.

An economic approach to assessing import policies designed to prevent the arrival of invasive species: the case of Puccinia psidii in Hawai'i

USGS Publications Warehouse

Burnett, Kimberly; D'Evelyn, Sean; Loope, Lloyd; Wada, Christopher A.

2012-01-01

Since its first documented introduction to Hawai‘i in 2005, the rust fungus Puccinia psidii has already severely damaged Syzygium jambos (Indian rose apple) trees and the federally endangered Eugenia koolauensis (nioi). Fortunately, the particular strain has yet to cause serious damage to Metrosideros polymorpha (‘ōhi‘a), which comprises roughly 80% of the state's native forests and covers 400,000 ha. Although the rust has affected less than 5% of Hawaii's ‘ōhi‘a trees thus far, the introduction of more virulent strains and the genetic evolution of the current strain are still possible. Since the primary pathway of introduction is Myrtaceae plant material imported from outside the state, potential damage to ‘ōhi‘a can be minimized by regulating those high-risk imports. We discuss the economic impact on the state's florist, nursery, landscaping, and forest plantation industries of a proposed rule that would ban the import of non-seed Myrtaceae plant material and require a 1-year quarantine of seeds. Our analysis suggests that the benefits to the forest plantation industry of a complete ban on non-seed material would likely outweigh the costs to other affected sectors, even without considering the reduction in risk to ‘ōhi‘a. Incorporating the value of ‘ōhi‘a protection would further increase the benefit–cost ratio in favor of an import ban.

The F-35 JSF: Beginning of the End for Blue-Water Ops?

DTIC Science & Technology

2010-04-06

DAMAGED BY INGESTING DEBRIS, THE RESULT OF SWITCHING TO A SINGLE-ENGINE AIRCRAFT FOR THE NAW’S PRIMARY FIGHTER. THE LOCKHEED MARTIN F-35 LIGHTNING II JOINT...States Navy Thesis: Single-engine aircraft have long been considered unsuitable for Naval Aviation, but now the future of blue-water operations is...dependent on the success and reliability of an aircraft · powered by a single engine, the Lockheed -Martin F-35Lightning II Joint Strike Fighter

Secondary impact hazard assessment

NASA Technical Reports Server (NTRS)

1986-01-01

A series of light gas gun shots (4 to 7 km/sec) were performed with 5 mg nylon and aluminum projectiles to determine the size, mass, velocity, and spatial distribution of spall and ejecta from a number of graphite/epoxy targets. Similar determinations were also performed on a few aluminum targets. Target thickness and material were chosen to be representative of proposed Space Station structure. The data from these shots and other information were used to predict the hazard to Space Station elements from secondary particles resulting from impacts of micrometeoroids and orbital debris on the Space Station. This hazard was quantified as an additional flux over and above the primary micrometeoroid and orbital debris flux that must be considered in the design process. In order to simplify the calculations, eject and spall mass were assumed to scale directly with the energy of the projectile. Other scaling systems may be closer to reality. The secondary particles considered are only those particles that may impact other structure immediately after the primary impact. The addition to the orbital debris problem from these primary impacts was not addressed. Data from this study should be fed into the orbital debris model to see if Space Station secondaries make a significant contribution to orbital debris. The hazard to a Space Station element from secondary particles above and beyond the micrometeoroid and orbital debris hazard is categorized in terms of two factors: (1) the 'view factor' of the element to other Space Station structure or the geometry of placement of the element, and (2) the sensitivity to damage, stated in terms of energy. Several example cases were chosen, the Space Station module windows, windows of a Shuttle docked to the Space Station, the habitat module walls, and the photovoltaic solar cell arrays. For the examples chosen the secondary flux contributed no more than 10 percent to the total flux (primary and secondary) above a given calculated critical energy. A key assumption in these calculations is that above a certain critical energy, significant damage will be done. This is not true for all structures. Double-walled, bumpered structures are an example for which damage may be reduced as energy goes up. The critical energy assumption is probably conservative, however, in terms of secondary damage. To understand why the secondary impacts seem to, in general, contribute less than 10 percent of the flux above a given critical energy, consider the case of a meteoroid impact of a given energy on a fixed, large surface. This impact results in a variety of secondary particles, all of which have much less energy than the original impact. Conservation of energy prohibits any other situation. Thus if damage is linked to a critical energy of a particle, the primary flux will always deliver particles of much greater energy. Even if all the secondary particles impacted other Space Station structures, none would have a kinetic energy more than a fraction of the primary impact energy.

Neutron radiation damage studies in the structural materials of a 500 MWe fast breeder reactor using DPA cross-sections from ENDF / B-VII.1

NASA Astrophysics Data System (ADS)

Saha, Uttiyoarnab; Devan, K.; Bachchan, Abhitab; Pandikumar, G.; Ganesan, S.

2018-04-01

The radiation damage in the structural materials of a 500 MWe Indian prototype fast breeder reactor (PFBR) is re-assessed by computing the neutron displacement per atom (dpa) cross-sections from the recent nuclear data library evaluated by the USA, ENDF / B-VII.1, wherein revisions were taken place in the new evaluations of basic nuclear data because of using the state-of-the-art neutron cross-section experiments, nuclear model-based predictions and modern data evaluation techniques. An indigenous computer code, computation of radiation damage (CRaD), is developed at our centre to compute primary-knock-on atom (PKA) spectra and displacement cross-sections of materials both in point-wise and any chosen group structure from the evaluated nuclear data libraries. The new radiation damage model, athermal recombination-corrected displacement per atom (arc-dpa), developed based on molecular dynamics simulations is also incorporated in our study. This work is the result of our earlier initiatives to overcome some of the limitations experienced while using codes like RECOIL, SPECTER and NJOY 2016, to estimate radiation damage. Agreement of CRaD results with other codes and ASTM standard for Fe dpa cross-section is found good. The present estimate of total dpa in D-9 steel of PFBR necessitates renormalisation of experimental correlations of dpa and radiation damage to ensure consistency of damage prediction with ENDF / B-VII.1 library.

Combined BC/MD approach to the evaluation of damage from fast neutrons and its implementation for beryllium irradiation in a fusion reactor

NASA Astrophysics Data System (ADS)

Borodin, V. A.; Vladimirov, P. V.

2017-12-01

The determination of primary damage production efficiency in metals irradiated with fast neutrons is a complex problem. Typically, the majority of atoms are displaced from their lattice positions not by neutrons themselves, but by energetic primary recoils, that can produce both single Frenkel pairs and dense localized cascades. Though a number of codes are available for the calculation of displacement damage from fast ions, they commonly use binary collision (BC) approximation, which is unreliable for dense cascades and thus tend to overestimate the number of created displacements. In order to amend the radiation damage predictions, this work suggests a combined approach, where the BC approximation is used for counting single Frenkel pairs only, whereas the secondary recoils able to produce localized dense cascades are stored for later processing, but not followed explicitly. The displacement production in dense cascades is then determined independently from molecular dynamics (MD) simulations. Combining contributions from different calculations, one gets the total number of displacements created by particular neutron spectrum. The approach is applied here to the case of beryllium irradiation in a fusion reactor. Using a relevant calculated energy spectrum of primary knocked-on atoms (PKAs), it is demonstrated that more than a half of the primary point defects (˜150/PKA) is produced by low-energy recoils in the form of single Frenkel pairs. The contribution to the damage from the dense cascades as predicted using the mixed BC/MD scheme, i.e. ˜110/PKA, is remarkably lower than the value deduced from uncorrected SRIM calculations (˜145/PKA), so that in the studied case SRIM tends to overpredict the total primary damage level.

Genomic Instability Associated with p53 Knockdown in the Generation of Huntington’s Disease Human Induced Pluripotent Stem Cells

PubMed Central

Tidball, Andrew M.; Neely, M. Diana; Chamberlin, Reed; Aboud, Asad A.; Kumar, Kevin K.; Han, Bingying; Bryan, Miles R.; Aschner, Michael; Ess, Kevin C.; Bowman, Aaron B.

2016-01-01

Alterations in DNA damage response and repair have been observed in Huntington’s disease (HD). We generated induced pluripotent stem cells (iPSC) from primary dermal fibroblasts of 5 patients with HD and 5 control subjects. A significant fraction of the HD iPSC lines had genomic abnormalities as assessed by karyotype analysis, while none of our control lines had detectable genomic abnormalities. We demonstrate a statistically significant increase in genomic instability in HD cells during reprogramming. We also report a significant association with repeat length and severity of this instability. Our karyotypically normal HD iPSCs also have elevated ATM-p53 signaling as shown by elevated levels of phosphorylated p53 and H2AX, indicating either elevated DNA damage or hypersensitive DNA damage signaling in HD iPSCs. Thus, increased DNA damage responses in the HD genotype is coincidental with the observed chromosomal aberrations. We conclude that the disease causing mutation in HD increases the propensity of chromosomal instability relative to control fibroblasts specifically during reprogramming to a pluripotent state by a commonly used episomal-based method that includes p53 knockdown. PMID:26982737

Radiation damage in a-SiO 2 exposed to intense positron pulses

NASA Astrophysics Data System (ADS)

Cassidy, D. B.; Mills, A. P.

2007-08-01

In addition to its numerous technological applications amorphous silica (a-SiO 2) is also well suited to the creation and study of exotic atoms such as positronium (Ps) and muonium. In particular, a dense Ps gas may be created by implanting an intense positron pulse into a porous a-SiO 2 sample. However, such positron pulses can constitute a significant dose of radiation, which may damage the sample. We have observed a reduction in the amount of Ps formed in a thin film of porous a-SiO 2 following irradiation by intense positron pulses, indicating the creation of paramagnetic centers. The data show that the primary effect of the irradiation is the inhibition of Ps formation, with no significant change in the subsequent Ps lifetime, from which we deduce that damage centers are created primarily in the bulk material and not on the internal surfaces of the pores, where they would be accessible to the long-lived Ps. We find that the damage is reversible, and that the system may be returned to its original state by heating to 700 K. The implications of these results for experiments with dense Ps in porous materials are discussed.

Impact of nuclear transmutations on the primary damage production: The example of Ni based steels

NASA Astrophysics Data System (ADS)

Luneville, Laurence; Sublet, Jean Christphe; Simeone, David

2018-07-01

The recent nuclear evaluations describe more accurately the elastic and inelastic neutron-atoms interactions and allow calculating more realistically primary damage induced by nuclear reactions. Even if these calculations do not take into account relaxation processes occurring at the end of the displacement cascade (calculations are performed within the Binary Collision Approximation), they can accurately describe primary and recoil spectra in different reactors opening the door for simulating aging of nuclear materials with Ion Beam facilities. Since neutrons are only sensitive to isotopes, these spectra must be calculated weighting isotope spectra by the isotopic composition of materials under investigation. To highlight such a point, primary damage are calculated in pure Ni exhibiting a meta-stable isotope produced under neutron flux by inelastic neutron-isotope processes. These calculations clearly point out that the instantaneous primary damage production, the displacement per atom rate (dpa/s), responsible for the micro-structure evolution, strongly depends on the 59N i isotopic fractions closely related to the inelastic neutron isotope processes. Since the isotopic composition of the meta-stable isotope vanishes for large fluences, the long term impact of this isotope does not largely modify drastically the total dpa number in Ni based steels materials irradiate in nuclear plants.

Dose-rate effect of ultrashort electron beam radiation on DNA damage and repair in vitro.

PubMed

Babayan, Nelly; Hovhannisyan, Galina; Grigoryan, Bagrat; Grigoryan, Ruzanna; Sarkisyan, Natalia; Tsakanova, Gohar; Haroutiunian, Samvel; Aroutiounian, Rouben

2017-11-01

Laser-generated electron beams are distinguished from conventional accelerated particles by ultrashort beam pulses in the femtoseconds to picoseconds duration range, and their application may elucidate primary radiobiological effects. The aim of the present study was to determine the dose-rate effect of laser-generated ultrashort pulses of 4 MeV electron beam radiation on DNA damage and repair in human cells. The dose rate was increased via changing the pulse repetition frequency, without increasing the electron energy. The human chronic myeloid leukemia K-562 cell line was used to estimate the DNA damage and repair after irradiation, via the comet assay. A distribution analysis of the DNA damage was performed. The same mean level of initial DNA damages was observed at low (3.6 Gy/min) and high (36 Gy/min) dose-rate irradiation. In the case of low-dose-rate irradiation, the detected DNA damages were completely repairable, whereas the high-dose-rate irradiation demonstrated a lower level of reparability. The distribution analysis of initial DNA damages after high-dose-rate irradiation revealed a shift towards higher amounts of damage and a broadening in distribution. Thus, increasing the dose rate via changing the pulse frequency of ultrafast electrons leads to an increase in the complexity of DNA damages, with a consequent decrease in their reparability. Since the application of an ultrashort pulsed electron beam permits us to describe the primary radiobiological effects, it can be assumed that the observed dose-rate effect on DNA damage/repair is mainly caused by primary lesions appearing at the moment of irradiation. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Investigation of Fuselage Structure Subject to Widespread Fatigue Damage

DOT National Transportation Integrated Search

1996-01-01

This report documents the results of the "Investigation of Fuselage Structure Subject to Widespread Fatigue Damage" contract. The primary program objective was to obtain data on airplane fuselage structures subject to multiple site damage (MSD) in an...

[Neuropsychological evaluation of children in low conciseness state after a severe traumatic brain injury].

PubMed

Fufaeva, E V; Mikadze, Yu V; Lukyanov, V I

2017-01-01

To follow up patterns of cognitive recovery in children (6-17 years of age) at the first four months after a severe traumatic brain injury (TBI). Seventeen children with TBI (GCS ≤8) were evaluated with the Coma Recovery Scale-R (CRS). Children were stratified into three groups according to their consciousness recovery. Seven children regained their consciousness completely and were assessed by the Luria Neuropsychological Battery test. Six children remained in the minimally conscious state (MCS) and were tested by the adapted procedure of neuropsychological assessment during the first four months. Four children with low level of consciousness were evaluated with CRS. The most destroying functions at the early recovery period were the processing speed (neurodynamics of mental activity), executive functions and memory. Children with the anterior cortex damage had the slowest dynamics of recovery. The slower dynamics of consciousness recovery was combined with severe primary damages of visual gnosis, speech and executive functions according to neuropsychological examination. The positive dynamics of consciousness recovery was combined with early behavioral changes and the greater rate of behavioral changes.

Chemistry of MOS-LSI radiation hardening

NASA Technical Reports Server (NTRS)

Grunthaner, P.

1985-01-01

The objective of this task was to obtain chemical information on MOS test samples. Toward this end, high resolution X-ray photoemission spectroscopy (XPS) has been the primary techniques used to characterize the chemistry and structure of the SiO2/Si interface for a variety of MOS structures with differing degrees of susceptibility to damage by ionizing radiation. The major accomplishments of this program are: (1) the identification of a structurally distinct region of SiO2 in the near-interfacial region of thermal SiO2 on Si; (2) the identification in the near-interfacial region of SiO2 structural differences between radiation hard and soft gate oxides; (3) the direct observation of radiation-induced damage sites in thermal SiO2 with XPS using in situ electron stress; (4) the correlation of suboxide state distributions at the SiO2/Si interface with processing parameters and radiation susceptibility; (5) the development of a chemical mechanism for radiation-induced interface state generation in SiO2/Si structures; and (6) the development benign chemical profiling techniques which permit the investigation of oxide/semiconductor structures using surface sensitive electron spectroscopic techniques.

The effects of monosodium urate monohydrate crystals on chondrocyte viability and function: implications for development of cartilage damage in gout.

PubMed

Chhana, Ashika; Callon, Karen E; Pool, Bregina; Naot, Dorit; Gamble, Gregory D; Dray, Michael; Pitto, Rocco; Bentley, Jarome; McQueen, Fiona M; Cornish, Jillian; Dalbeth, Nicola

2013-12-01

Cartilage damage is frequently observed in advanced destructive gout. The aim of our study was to investigate the effects of monosodium urate monohydrate (MSU) crystals on chondrocyte viability and function. The alamarBlue assay and flow cytometry were used to assess the viability of primary human chondrocytes and cartilage explants following culture with MSU crystals. The number of dead chondrocytes in cartilage explants cultured with MSU crystals was quantified. Real-time PCR was used to determine changes in the relative mRNA expression levels of chondrocytic genes. The histological appearance of cartilage in joints affected by gout was also examined. MSU crystals rapidly reduced primary human chondrocyte and cartilage explant viability in a dose-dependent manner (p < 0.01 for both). Cartilage explants cultured with MSU crystals had a greater percentage of dead chondrocytes at the articular surface compared to untreated cartilage (p = 0.004). Relative mRNA expression of type II collagen and the cartilage matrix proteins aggrecan and versican was decreased in chondrocytes following culture with MSU crystals (p < 0.05 for all). However, expression of the degradative enzymes ADAMTS4 and ADAMTS5 was increased (p < 0.05 for both). In joints affected by gout, normal cartilage architecture was lost, with empty chondrocyte lacunae observed. MSU crystals have profound inhibitory effects on chondrocyte viability and function. Interactions between MSU crystals and chondrocytes may contribute to cartilage damage in gout through reduction of chondrocyte viability and promotion of a catabolic state.

On multi-site damage identification using single-site training data

NASA Astrophysics Data System (ADS)

Barthorpe, R. J.; Manson, G.; Worden, K.

2017-11-01

This paper proposes a methodology for developing multi-site damage location systems for engineering structures that can be trained using single-site damaged state data only. The methodology involves training a sequence of binary classifiers based upon single-site damage data and combining the developed classifiers into a robust multi-class damage locator. In this way, the multi-site damage identification problem may be decomposed into a sequence of binary decisions. In this paper Support Vector Classifiers are adopted as the means of making these binary decisions. The proposed methodology represents an advancement on the state of the art in the field of multi-site damage identification which require either: (1) full damaged state data from single- and multi-site damage cases or (2) the development of a physics-based model to make multi-site model predictions. The potential benefit of the proposed methodology is that a significantly reduced number of recorded damage states may be required in order to train a multi-site damage locator without recourse to physics-based model predictions. In this paper it is first demonstrated that Support Vector Classification represents an appropriate approach to the multi-site damage location problem, with methods for combining binary classifiers discussed. Next, the proposed methodology is demonstrated and evaluated through application to a real engineering structure - a Piper Tomahawk trainer aircraft wing - with its performance compared to classifiers trained using the full damaged-state dataset.

The use of the SRIM code for calculation of radiation damage induced by neutrons

NASA Astrophysics Data System (ADS)

Mohammadi, A.; Hamidi, S.; Asadabad, Mohsen Asadi

2017-12-01

Materials subjected to neutron irradiation will being evolve to structural changes by the displacement cascades initiated by nuclear reaction. This study discusses a methodology to compute primary knock-on atoms or PKAs information that lead to radiation damage. A program AMTRACK has been developed for assessing of the PKAs information. This software determines the specifications of recoil atoms (using PTRAC card of MCNPX code) and also the kinematics of interactions. The deterministic method was used for verification of the results of (MCNPX+AMTRACK). The SRIM (formely TRIM) code is capable to compute neutron radiation damage. The PKAs information was extracted by AMTRACK program, which can be used as an input of SRIM codes for systematic analysis of primary radiation damage. Then the Bushehr Nuclear Power Plant (BNPP) radiation damage on reactor pressure vessel is calculated.

Replicative stress and alterations in cell cycle checkpoint controls following acetaminophen hepatotoxicity restrict liver regeneration.

PubMed

Viswanathan, Preeti; Sharma, Yogeshwar; Gupta, Priya; Gupta, Sanjeev

2018-03-05

Acetaminophen hepatotoxicity is a leading cause of hepatic failure with impairments in liver regeneration producing significant mortality. Multiple intracellular events, including oxidative stress, mitochondrial damage, inflammation, etc., signify acetaminophen toxicity, although how these may alter cell cycle controls has been unknown and was studied for its significance in liver regeneration. Assays were performed in HuH-7 human hepatocellular carcinoma cells, primary human hepatocytes and tissue samples from people with acetaminophen-induced acute liver failure. Cellular oxidative stress, DNA damage and cell proliferation events were investigated by mitochondrial membrane potential assays, flow cytometry, fluorescence staining, comet assays and spotted arrays for protein expression after acetaminophen exposures. In experimental groups with acetaminophen toxicity, impaired mitochondrial viability and substantial DNA damage were observed with rapid loss of cells in S and G2/M and cell cycle restrictions or even exit in the remainder. This resulted from altered expression of the DNA damage regulator, ATM and downstream transducers, which imposed G1/S checkpoint arrest, delayed entry into S and restricted G2 transit. Tissues from people with acute liver failure confirmed hepatic DNA damage and cell cycle-related lesions, including restrictions of hepatocytes in aneuploid states. Remarkably, treatment of cells with a cytoprotective cytokine reversed acetaminophen-induced restrictions to restore cycling. Cell cycle lesions following mitochondrial and DNA damage led to failure of hepatic regeneration in acetaminophen toxicity but their reversibility offers molecular targets for treating acute liver failure. © 2018 John Wiley & Sons Ltd.

A Multi-Model Framework to Achieve Consistent Evaluation of Climate Change Impacts in the United States

NASA Astrophysics Data System (ADS)

Sarofim, M. C.; Martinich, J.; Waldhoff, S.; DeAngelo, B. J.; McFarland, J.; Jantarasami, L.; Shouse, K.; Crimmins, A.; Li, J.

2014-12-01

The Climate Change Impacts and Risk Analysis (CIRA) project establishes a new multi-model framework to systematically assess the physical impacts, economic damages, and risks from climate change. The primary goal of this framework is to estimate the degree to which climate change impacts and damages in the United States are avoided or reduced in the 21st century under multiple greenhouse gas (GHG) emissions mitigation scenarios. The first phase of the CIRA project is a modeling exercise that included two integrated assessment models and 15 sectoral models encompassing five broad impacts sectors: water resources, electric power, infrastructure, human health, and ecosystems. Three consistent socioeconomic and climate scenarios are used to analyze the benefits of global GHG mitigation targets: a reference scenario and two policy scenarios with total radiative forcing targets in 2100 of 4.5 W/m2 and 3.7 W/m2. In this exercise, the implications of key uncertainties are explored, including climate sensitivity, climate model, natural variability, and model structures and parameters. This presentation describes the motivations and goals of the CIRA project; the design and academic contribution of the first CIRA modeling exercise; and briefly summarizes several papers published in a special issue of Climatic Change. The results across impact sectors show that GHG mitigation provides benefits to the United States that increase over time, the effects of climate change can be strongly influenced by near-term policy choices, adaptation can reduce net damages, and impacts exhibit spatial and temporal patterns that may inform mitigation and adaptation policy discussions.

C-NAP1 and rootletin restrain DNA damage-induced centriole splitting and facilitate ciliogenesis.

PubMed

Conroy, Pauline C; Saladino, Chiara; Dantas, Tiago J; Lalor, Pierce; Dockery, Peter; Morrison, Ciaran G

2012-10-15

Cilia are found on most human cells and exist as motile cilia or non-motile primary cilia. Primary cilia play sensory roles in transducing various extracellular signals, and defective ciliary functions are involved in a wide range of human diseases. Centrosomes are the principal microtubule-organizing centers of animal cells and contain two centrioles. We observed that DNA damage causes centriole splitting in non-transformed human cells, with isolated centrioles carrying the mother centriole markers CEP170 and ninein but not kizuna or cenexin. Loss of centriole cohesion through siRNA depletion of C-NAP1 or rootletin increased radiation-induced centriole splitting, with C-NAP1-depleted isolated centrioles losing mother markers. As the mother centriole forms the basal body in primary cilia, we tested whether centriole splitting affected ciliogenesis. While irradiated cells formed apparently normal primary cilia, most cilia arose from centriolar clusters, not from isolated centrioles. Furthermore, C-NAP1 or rootletin knockdown reduced primary cilium formation. Therefore, the centriole cohesion apparatus at the proximal end of centrioles may provide a target that can affect primary cilium formation as part of the DNA damage response.

Atomic scale modeling of defect production and microstructure evolution in irradiated metals

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

Diaz de la Rubia, T.; Soneda, N.; Shimomura, Y.

1997-04-01

Irradiation effects in materials depend in a complex way on the form of the as-produced primary damage state and its spatial and temporal evolution. Thus, while collision cascades produce defects on a time scale of tens of picosecond, diffusion occurs over much longer time scales, of the order of seconds, and microstructure evolution over even longer time scales. In this report the authors present work aimed at describing damage production and evolution in metals across all the relevant time and length scales. They discuss results of molecular dynamics simulations of displacement cascades in Fe and V. They show that interstitialmore » clusters are produced in cascades above 5 keV, but not vacancy clusters. Next, they discuss the development of a kinetic Monte Carlo model that enables calculations of damage evolution over much longer time scales (1000`s of s) than the picosecond lifetime of the cascade. They demonstrate the applicability of the method by presenting predictions on the fraction of freely migrating defects in {alpha}Fe during irradiation at 600 K.« less

Radiation-induced cardiomyopathy as a function of radiation beam gating to the cardiac cycle

NASA Astrophysics Data System (ADS)

Gladstone, David J.; Flanagan, Michael F.; Southworth, Jean B.; Hadley, Vaughn; Thibualt, Melissa Wei; Hug, Eugen B.; Hoopes, P. Jack

2004-04-01

Portions of the heart are often unavoidably included in the primary treatment volume during thoracic radiotherapy, and radiation-induced heart disease has been observed as a treatment-related complication. Such complications have been observed in humans following radiation therapy for Hodgkin's disease and treatment of the left breast for carcinoma. Recent attempts have been made to prevent re-stenosis following angioplasty procedures using external beam irradiation. These attempts were not successful, however, due to the large volume of heart included in the treatment field and subsequent cardiac morbidity. We suggest a mechanism for sparing the heart from radiation damage by synchronizing the radiation beam with the cardiac cycle and delivering radiation only when the heart is in a relatively hypoxic state. We present data from a rat model testing this hypothesis and show that radiation damage to the heart can be altered by synchronizing the radiation beam with the cardiac cycle. This technique may be useful in reducing radiation damage to the heart secondary to treatment for diseases such as Hodgkin's disease and breast cancer.

A Pressure-Dependent Damage Model for Energetic Materials

DTIC Science & Technology

2013-04-01

appropriate damage nucleation and evolution laws, and the equation of state ) with its reactive response. 15. SUBJECT TERMS pressure-dependent...evolution laws, and the equation of state ) with its reactive response. INTRODUCTION Explosions and deflagrations are classifications of sub-detonative...energetic material’s mechanical response (through the yield criterion, damage evolution and equation of state ) with its reactive response. DAMAGE-FREE

Effectiveness of two conventional methods for seismic retrofit of steel and RC moment resisting frames based on damage control criteria

NASA Astrophysics Data System (ADS)

Beheshti Aval, Seyed Bahram; Kouhestani, Hamed Sadegh; Mottaghi, Lida

2017-07-01

This study investigates the efficiency of two types of rehabilitation methods based on economic justification that can lead to logical decision making between the retrofitting schemes. Among various rehabilitation methods, concentric chevron bracing (CCB) and cylindrical friction damper (CFD) were selected. The performance assessment procedure of the frames is divided into two distinct phases. First, the limit state probabilities of the structures before and after rehabilitation are investigated. In the second phase, the seismic risk of structures in terms of life safety and financial losses (decision variables) using the recently published FEMA P58 methodology is evaluated. The results show that the proposed retrofitting methods improve the serviceability and life safety performance levels of steel and RC structures at different rates when subjected to earthquake loads. Moreover, these procedures reveal that financial losses are greatly decreased, and were more tangible by the application of CFD rather than using CCB. Although using both retrofitting methods reduced damage state probabilities, incorporation of a site-specific seismic hazard curve to evaluate mean annual occurrence frequency at the collapse prevention limit state caused unexpected results to be obtained. Contrary to CFD, the collapse probability of the structures retrofitted with CCB increased when compared with the primary structures.

Raster microdiffraction with synchrotron radiation of hydrated biopolymers with nanometre step-resolution: case study of starch granules

PubMed Central

Riekel, C.; Burghammer, M.; Davies, R. J.; Di Cola, E.; König, C.; Lemke, H.T.; Putaux, J.-L.; Schöder, S.

2010-01-01

X-ray radiation damage propagation is explored for hydrated starch granules in order to reduce the step resolution in raster-microdiffraction experiments to the nanometre range. Radiation damage was induced by synchrotron radiation microbeams of 5, 1 and 0.3 µm size with ∼0.1 nm wavelength in B-type potato, Canna edulis and Phajus grandifolius starch granules. A total loss of crystallinity of granules immersed in water was found at a dose of ∼1.3 photons nm−3. The temperature dependence of radiation damage suggests that primary radiation damage prevails up to about 120 K while secondary radiation damage becomes effective at higher temperatures. Primary radiation damage remains confined to the beam track at 100 K. Propagation of radiation damage beyond the beam track at room temperature is assumed to be due to reactive species generated principally by water radiolysis induced by photoelectrons. By careful dose selection during data collection, raster scans with 500 nm step-resolution could be performed for granules immersed in water. PMID:20975219

Primary DNA damage and genetic polymorphisms for CYP1A1, EPHX and GSTM1 in workers at a graphite electrode manufacturing plant

PubMed Central

Moretti, Massimo; Dell'Omo, Marco; Villarini, Milena; Pastorelli, Roberta; Muzi, Giacomo; Airoldi, Luisa; Pasquini, Rossana

2007-01-01

Background The results of a cross-sectional study aimed to evaluate whether genetic polymorphisms (biomarkers of susceptibility) for CYP1A1, EPHX and GSTM1 genes that affect polycyclic aromatic hydrocarbons (PAH) activation and detoxification might influence the extent of primary DNA damage (biomarker of biologically effective dose) in PAH exposed workers are presented. PAH-exposure of the study populations was assessed by determining the concentration of 1-hydroxypyrene (1OHP) in urine samples (biomarker of exposure dose). Methods The exposed group consisted of workers (n = 109) at a graphite electrode manufacturing plant, occupationally exposed to PAH. Urinary 1OHP was measured by HPLC. Primary DNA damage was evaluated by the alkaline comet assay in peripheral blood leukocytes. Genetic polymorphisms for CYP1A1, EPHX and GSTM1 were determined by PCR or PCR/RFLP analysis. Results 1OHP and primary DNA damage were significantly higher in electrode workers compared to reference subjects. Moreover, categorization of subjects as normal or outlier highlighted an increased genotoxic risk OR = 2.59 (CI95% 1.32–5.05) associated to exposure to PAH. Polymorphisms in EPHX exons 3 and 4 was associated to higher urinary concentrations of 1OHP, whereas none of the genotypes analyzed (CYP1A1, EPHX, and GSTM1) had any significant influence on primary DNA damage as evaluated by the comet assay. Conclusion The outcomes of the present study show that molecular epidemiology approaches (i.e. cross-sectional studies of genotoxicity biomarkers) can play a role in identifying common genetic risk factors, also attempting to associate the effects with measured exposure data. Moreover, categorization of subjects as normal or outlier allowed the evaluation of the association between occupational exposure to PAH and DNA damage highlighting an increased genotoxic risk. PMID:17908297

Atomistic modeling and experimental studies of radiation damage in monazite-type LaPO4 ceramics

NASA Astrophysics Data System (ADS)

Ji, Yaqi; Kowalski, Piotr M.; Neumeier, Stefan; Deissmann, Guido; Kulriya, Pawan K.; Gale, Julian D.

2017-02-01

We simulated the threshold displacement energies (Ed), the related displacement and defect formation probabilities, and the energy barriers in LaPO4 monazite-type ceramics. The obtained Ed values for La, P, O primary knock-on atoms (PKA) are 56 eV, 75 eV and 8 eV, respectively. We found that these energies can be correlated with the energy barriers that separate the defect from the initial states. The Ed values are about twice the values of energy barriers, which is explained through an efficient dissipation of the PKA kinetic energy in the considered system. The computed Ed were used in simulations of the extent of radiation damage in La0.2Gd0.8PO4 solid solution, investigated experimentally. We found that this lanthanide phosphate fully amorphises in the ion beam experiments for fluences higher than ∼1013 ions/cm2.

Regionalized life cycle impact assessment of air pollution on the global scale: Damage to human health and vegetation

NASA Astrophysics Data System (ADS)

van Zelm, Rosalie; Preiss, Philipp; van Goethem, Thomas; Van Dingenen, Rita; Huijbregts, Mark

2016-06-01

We developed regionalized characterization factors (CFs) for human health damage from particulate matter (PM2.5) and ozone, and for damage to vegetation from ozone, at the global scale. These factors can be used in the impact assessment phase of an environmental life cycle assessment. CFs express the overall damage of a certain pollutant per unit of emission of a precursor, i.e. primary PM2.5, nitrogen oxides (NOx), ammonia (NH3), sulfur dioxide (SO2) and non-methane volatile organic compounds (NMVOCs). The global chemical transport model TM5 was used to calculate intake fractions of PM2.5 and ozone for 56 world regions covering the whole globe. Furthermore, region-specific effect and damage factors were derived, using mortality rates, background concentrations and years of life lost. The emission-weighted world average CF for primary PM2.5 emissions is 629 yr kton-1, varying up to 3 orders of magnitude over the regions. Larger CFs were obtained for emissions in central Asia and Europe, and smaller factors in Australia and South America. The world average CFs for PM2.5 from secondary aerosols, i.e. NOx, NH3, and SO2, is 67.2 to 183.4 yr kton-1. We found that the CFs for ozone human health damage are 2-4 orders of magnitude lower compared to the CFs for damage due to primary PM2.5 and PM2.5 precursor emissions. Human health damage due to the priority air pollutants considered in this study was 1.7·10-2 yr capita-1 worldwide in year 2010, with primary PM2.5 emissions as the main contributor (62%). The emission-weighted world average CF for ecosystem damage due to ozone was 2.5 km2 yr kton-1 for NMVOCs and 8.7 m2 yr kg-1 for NOx emissions, varying 2-3 orders of magnitude over the regions. Ecosystem damage due to the priority air pollutants considered in this study was 1.6·10-4 km2 capita-1 worldwide in 2010, with NOx as the main contributor (72%). The spatial range in CFs stresses the importance of including spatial variation in life cycle impact assessment of priority air pollutants.

77 FR 44562 - Housing Assistance Due to Structural Damage

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

...: Temporary Housing: Money is available to rent a different place to live for a limited period of time. When... housing unit. Housing Repair: Money is available to homeowners to repair disaster damage to their primary... make the damaged home safe, sanitary, and functional. Housing Replacement: Money is available to...

Postradiation atrophy of mature bone

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

Erguen, H.; Howland, W.J.

1980-01-01

The growing number of oncological patients subjected to radiotherapy require the diagnostic radiologist to be aware of expected bone changes following irradiation and the differentiation of this entity from metastasis. The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographicmore » evidence of atrophy, localized osteopenia, is late in appearing, mainly because of the relative insensitivity of radiographs in detecting demineralization. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. In vivo midrodensitometric analysis and radionuclide bone and bone marrow scans can reveal early changes following irradiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.« less

Postradiation atrophy of mature bone

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

Ergun, H.; Howland, W.J.

1980-01-01

The growing number of oncological patients subjected to radiotherapy require the diagnostic radiologist to be aware of expected bone changes following irradiation and the differentiation of this entity from metastasis. The primary event of radiation damage to bone is atrophy and true necrosis of bone is uncommon. The postradiation atrophic changes of bone are the result of combined cellular and vascular damage, the former being more important. The damage to the osteoblast resulting in decreased matrix production is apparently the primary histopathologic event. Radiation damaged bone is susceptible to superimposed complications of fracture, infection, necrosis, and sarcoma. The primary radiographicmore » evidence of atrophy, localized osteopenia, is late in appearing, mainly because of the relative insensitivity of radiographs in detecing demineralization. Contrary to former views, the mature bone is quite radiosensitive and reacts quickly to even small doses of radiation. In vivo midrodensitometric analysis and radionuclide bone and bone marrow scans can reveal early changes following irradiation. The differentiation of postirradiation atrophy and metastasis may be difficult. Biopsy should be the last resort because of the possibility of causing true necrosis in atrophic bone by trauma and infection.« less

Monitoring exposure of brown bullheads and benthic macroinvertebrates to sediment contaminants in the Ashtabula River before, during, and after remediation.

PubMed

Meier, John R; Lazorchak, James M; Mills, Marc; Wernsing, Paul; Baumann, Paul C

2015-06-01

In 2007, approximately 420,500 cubic meters of contaminated sediment were removed from the Ashtabula River by dredging. The primary objective of the present study was to monitor contaminant exposure in fish and macroinvertebrates before, during, and after dredging. This was done by measuring tissue concentrations of polychlorinated biphenyl (PCB) and polycyclic aromatic hydrocarbon (PAH) in brown bullhead catfish (Ameriurus nebulosa) and in benthic macroinvertebrates, assessing changes in DNA damage in fish liver and blood, and scoring external and histopathological lesions and anomalies in the fish. In surficial sediment PCBs and PAHs were also quantified in conjunction with the biological sampling. The results show a significant reduction in contaminant levels in both fish and macroinvertebrates following dredging, indicating the effectiveness of the remediation in reducing exposure of biota to the primary contaminants of concern. Similarly, DNA damage levels in fish collected from the Ashtabula River significantly declined following dredging; however, a similar reduction in DNA damage over time was seen in fish collected from a reference site (Conneaut Creek), making interpretation difficult. Macroinvertebrate PCB concentrations were reflective of the sediment concentrations in the areas where Hester-Dendy samplers were deployed for macroinvertebrate collection. The present study demonstrates that these methods can be used to evaluate and assess the effectiveness of remediation techniques at contaminated sediment sites. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Features of primary damage by high energy displacement cascades in concentrated Ni-based alloys

DOE PAGES

Béland, Laurent Karim; Lu, Chenyang; Osetskiy, Yuri N.; ...

2016-02-25

Alloying of Ni with Fe or Co reduces primary damage production under ion irradiation. Similar results have been obtained from classical molecular dynamics simulations of 1, 10, 20, and 40 keV collision cascades in Ni, NiFe, and NiCo. In all cases, a mix of imperfect stacking fault tetrahedra, faulted loops with a 1/3 {111} Burgers vector, and glissile interstitial loops with a 1/2 {110} Burgers vector were formed, along with small sessile point defect complexes and clusters. Primary damage reduction occurs by three mechanisms. First, Ni-Co, Ni-Fe, Co-Co, and Fe-Fe short-distance repulsive interactions are stiffer than Ni-Ni interactions, which leadmore » to a decrease in damage formation during the transition from the supersonic ballistic regime to the sonic regime. This largely controls final defect production. Second, alloying decreases thermal conductivity, leading to a longer thermal spike lifetime. The associated annealing reduces final damage production. These two mechanisms are especially important at cascades energies less than 40 keV. Third, at the higher energies, the production of large defect clusters by subcascades is inhibited in the alloys. A number of challenges and limitations pertaining to predictive atomistic modeling of alloys under high-energy particle irradiation are discussed.« less

Prospective data collection and analysis of perforations and tears of latex surgical gloves during primary endoprosthetic surgeries.

PubMed

Zaatreh, Sarah; Enz, Andreas; Klinder, Annett; König, Tony; Mittelmeier, Lena; Kundt, Günther; Mittelmeier, Wolfram

2016-01-01

Introduction: Surgical gloves are used to prevent contamination of the patient and the hospital staff with pathogens. The aim of this study was to examine the actual effectiveness of gloves by examining the damage (perforations, tears) to latex gloves during surgery in the case of primary hip and knee prosthesis implantation. Materials and methods: Latex surgical gloves used by surgeons for primary hip and knee replacement surgeries were collected directly after the surgery and tested using the watertightness test according to ISO EN 455-1:2000. Results: 540 gloves were collected from 104 surgeries. In 32.7% of surgeries at least one glove was damaged. Of all the gloves collected, 10.9% were damaged, mainly on the index finger. The size of the perforations ranged from ≤1 mm to over 5 mm. The surgeon's glove size was the only factor that significantly influenced the occurrence of glove damage. Surgeon training level, procedure duration, and the use of bone cement had no significant influence. Conclusions: Our results highlight the high failure rate of surgical gloves. This has acute implications for glove production, surgical practice, and hygiene guidelines. Further studies are needed to detect the surgical steps, surface structures, and instruments that pose an increased risk for glove damage.

Differential response of two cell lines sequentially irradiated with low X-ray doses.

PubMed

Güerci, A M; Dulout, F N; Grillo, C A; Seoane, A I

2005-05-01

An experiment was designed to compare the effect of repeated low doses of X-rays in two different cell lines: one transformed, epithelial like and aneuploid Chinese hamster ovary K-1 (CHO-K1); the other originated from a human primary culture, fibroblast, diploid and non-transformed, MRC-5. CHO and MRC-5 cells were cultured for 14 or eight passages, respectively. Irradiation was performed once per passage when cells were in the quiescent state (90 - 95% in G1/G0). Cells were exposed to 10.0 mSv X-ray doses. Ionizing radiation did not induce apoptosis or necrosis in the exposed CHO cell population. Significant increases of low-level damaged cells (degrees 1 and 2) were found for the 14 cycles of radiation when compared with controls, except for the first irradiation cycle. No significant increases in the frequency of cells with severe damage were observed. The frequency of MRC-5 cells with low-level damage increased significantly when compared with controls for radiation cycles seven and eight. Significant increases of apoptosis, necrosis and severe damage were found only for the highest dose. Transformed and non-transformed cell types responded differently to direct and indirect damage using low-dose repeat exposures to ionizing radiation. Though more investigation is needed to understand the mechanisms of radiation effects in chronic low-dose-exposed cell populations, cellular type should be taken into account in the design of in vitro experiments for understanding low-dose-irradiation effects.

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

Barr, Jonathan L.; Taira, Randal Y.; Orr, Heather M.

The purpose of this document is to describe the operating concepts, capabilities, and benefits of RAMS including descriptions of how the system implementations can improve emergency response, damage assessment, task prioritization, and situation awareness. This CONOPS provides general information on operational processes and procedures required to utilize RAMS, and expected performance benefits of the system. The primary audiences for this document are the end users of RAMS (including flight operators and incident commanders) and the RAMS management team. Other audiences include interested offices within the Department of Homeland Security (DHS), and officials from other state and local jurisdictions who wantmore » to implement similar systems.« less

[Neuroplasticity as a basis for early rehabilitation of stroke patients].

PubMed

Putilina, M V

2011-01-01

The review is devoted to the current state of the problem of early rehabilitation of stroke patients. The rate of primary disability in patients after stroke is 3.2 per 10000 population but only 20% of previously working patients return to work. Early rehabilitation is treatment actions during a period following stroke. Adequate treatment during this period may decrease the extent of brain damage and improve disease outcome. The complexity of rehabilitation consists in using several complementary pharmacological and non-pharmacological rehabilitation measures. Appearance of new techniques of rehabilitation treatment aimed at neuroplasticity stimulation increases treatment potential of rehabilitative technologies.

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

Stoller, Roger E; Nordlund, Kai; Melerba, L

The processes that give rise to changes in the microstructure and the physical and mechanical properties of materials exposed to energetic particles are initiated by essentially elastic collisions between atoms in what has been called an atomic displacement cascade. The formation and evolution of this primary radiation damage mechanism are described to provide an overview of how stable defects are formed by displacement cascades, as well as the nature and morphology of the defects themselves. The impact of the primary variables cascade energy and irradiation temperature are discussed, along with a range of secondary factors that can influence damage formation.Radiation-inducedmore » changes in microstructure and mechanical properties in structural materials are the result of a complex set of physical processes initiated by the collision between an energetic particle (neutron or ion) and an atom in the lattice. This primary damage event is called an atomic displacement cascade. The simplest description of a displacement cascade is to view it as a series of many billiard-ball-like elastic collisions among the atoms in the material. This chapter describes the formation and evolution of this primary radiation damage mechanism to provide an overview of how stable defects are formed by displacement cascades, as well as the nature and morphology of the defects themselves. The impact of the relevant variables such as cascade energy and irradiation temperature is discussed, and defect formation in different materials is compared.« less

[A Study on Quantitative Evaluation of Damage in Conservation of Ceramics from Huaguangjiao I Shipwreck with ICP-AES].

PubMed

Li, Wen-jing; Chen, Yue; Li, Nai-sheng; Li, Bin; Luo, Wu-gan

2015-03-01

ICP-AES was used to determine the elemental composition of solutions in different conservation steps for understanding the impact of cleaning agents on ceramics from Huaguangjiao I shipwreck. The results showed that high content in solution of Al, Fe, Mg ions, which can be indexes to reflect the damage in conservation of ceramics. According to these indexes, we discovered that agents of strong cleaning ability bring more damage to ceramic samples. Meanwhile, the state of preservation of the ceramics was closely related to the damage in conservation. Ceramics in an excellent state of preservation endure less damage than that in bad state. We also found that each cleaning agent cause certain degree of damage on porcelains, even neutral reagent, like deionized water. Moreover, moderate cleaning reagent, when using a long time, bring the same degree of damage as the strong acid. Therefore, in actual protection procedure, for conservation ceramics safe and effective, damage of each cleaning agents and cumulative damage should be considered.

Overview of the Special Issue: A Multi-Model Framework to ...

EPA Pesticide Factsheets

The Climate Change Impacts and Risk Analysis (CIRA) project establishes a new multi-model framework to systematically assess the impacts, economic damages, and risks from climate change in the United States. The primary goal of this framework to estimate how climate change impacts and damages in the United States are avoided or reduced due to global greenhouse gas (GHG) emissions mitigation scenarios. Scenarios are designed to explore key uncertainties around the measurement of these changes. The modeling exercise presented in this Special Issue includes two integrated assessment models and 15 sectoral models encompassing six broad impacts sectors - water resources, electric power, infrastructure, human health, ecosystems, and forests. Three consistent emissions scenarios are used to analyze the benefits of global GHG mitigation targets: a reference and two policy scenarios, with total radiative forcing in 2100 of 10.0W/m2, 4.5W/m2, and 3.7W/m2. A range of climate sensitivities, climate models, natural variability measures, and structural uncertainties of sectoral models are examined to explore the implications of key uncertainties. This overview paper describes the motivations, goals, design, and academic contribution of the CIRA modeling exercise and briefly summarizes the subsequent papers in this Special Issue. A summary of results across impact sectors is provided showing that: GHG mitigation provides benefits to the United States that increase over

The distribution of DNA damage is defined by region-specific susceptibility to DNA damage formation rather than repair differences.

PubMed

Strand, Janne M; Scheffler, Katja; Bjørås, Magnar; Eide, Lars

2014-06-01

The cellular genomes are continuously damaged by reactive oxygen species (ROS) from aerobic processes. The impact of DNA damage depends on the specific site as well as the cellular state. The steady-state level of DNA damage is the net result of continuous formation and subsequent repair, but it is unknown to what extent heterogeneous damage distribution is caused by variations in formation or repair of DNA damage. Here, we used a restriction enzyme/qPCR based method to analyze DNA damage in promoter and coding regions of four nuclear genes: the two house-keeping genes Gadph and Tbp, and the Ndufa9 and Ndufs2 genes encoding mitochondrial complex I subunits, as well as mt-Rnr1 encoded by mitochondrial DNA (mtDNA). The distribution of steady-state levels of damage varied in a site-specific manner. Oxidative stress induced damage in nDNA to a similar extent in promoter and coding regions, and more so in mtDNA. The subsequent removal of damage from nDNA was efficient and comparable with recovery times depending on the initial damage load, while repair of mtDNA was delayed with subsequently slower repair rate. The repair was furthermore found to be independent of transcription or the transcription-coupled repair factor CSB, but dependent on cellular ATP. Our results demonstrate that the capacity to repair DNA is sufficient to remove exogenously induced damage. Thus, we conclude that the heterogeneous steady-state level of DNA damage in promoters and coding regions is caused by site-specific DNA damage/modifications that take place under normal metabolism. Copyright © 2014 Elsevier B.V. All rights reserved.

Proton irradiation effects on gallium nitride-based devices

NASA Astrophysics Data System (ADS)

Karmarkar, Aditya P.

Proton radiation effects on state-of-the-art gallium nitride-based devices were studied using Schottky diodes and high electron-mobility transistors. The device degradation was studied over a wide range of proton fluences. This study allowed for a correlation between proton irradiation effects between different types of devices and enhanced the understanding of the mechanisms responsible for radiation damage in GaN-based devices. Proton irradiation causes reduced carrier concentration and increased series resistance and ideality factor in Schottky diodes. 1.0-MeV protons cause greater degradation than 1.8-MeV protons because of their higher non-ionizing energy loss. The displacement damage in Schottky diodes recovers during annealing. High electron-mobility transistors exhibit extremely high radiation tolerance, continuing to perform up to a fluence of ˜1014 cm-2 of 1.8-MeV protons. Proton irradiation creates defect complexes in the thin-film structure. Decreased sheet carrier mobility due to increased carrier scattering and decreased sheet carrier density due to carrier removal by the defect centers are the primary damage mechanisms. Interface disorder at either the Schottky or the Ohmic contact plays a relatively unimportant part in overall device degradation in both Schottky diodes and high electron-mobility transistors.

The effect of magnetic and non-magnetic ion damage on the surface state in SmB 6

DOE PAGES

Wakeham, N.; Wen, J.; Wang, Y. Q.; ...

2015-07-14

SmB 6 is a Kondo insulator with a band structure that is topologically distinct from the vacuum. We theoretically predict this in order to produce metallic topological surface states that are robust to perturbations that do not break time reversal symmetry, such as non-magnetic defects. But, the surface state may be destroyed by an impurity with a sufficiently large magnetic moment. In order to test this prediction we show measurements of the resistance of the surface state of single crystals of SmB 6 with varying levels of damage induced by magnetic and non-magnetic ion irradiation. Finally, we find that atmore » a sufficiently high concentration of damage the surface state reconstructs below an amorphous damaged layer, whether the damage was caused by a magnetic or non-magnetic ion.« less

The Fukushima Nuclear Disaster and the U.S. Customs and Border Protection Response

NASA Astrophysics Data System (ADS)

McCormick, Kathy

2013-10-01

On 3/11/11, the reactors at the Fukushima Nuclear Plant in Japan were damaged by a magnitude 9.0 earthquake. Of the six reactors at the site, three were in operation prior to the event, and were automatically shut-down during the earthquake. Emergency cooling systems came online and were subsequently destroyed by a tsunami generated by the earthquake. For the operating reactors, all the reactor cores were exposed, resulting in overheating and the release of steam and hydrogen gas to the containment vessels, several of which subsequently exploded, releasing radioactivity into the atmosphere. The cores of the operating reactors melted down, and radioactive water was released to the ocean in cooling efforts. The primary radiation concerns in the United States from the disaster were radioactive plumes driven by westerly winds and contaminated commercial products and travelers. In the United States, one of the primary governmental organizations to respond to the disaster was U.S. Customs and Border Protection (CBP), which has responsibility to oversee the safety and security of cargo and travelers entering the United States. This talk will describe the various types of radioactive commodities and events encountered by CBP in the U.S. from the Fukushima disaster. Thanks to the CBP Teleforensics Center for their assistance with this presentation.

A response surface methodology based damage identification technique

NASA Astrophysics Data System (ADS)

Fang, S. E.; Perera, R.

2009-06-01

Response surface methodology (RSM) is a combination of statistical and mathematical techniques to represent the relationship between the inputs and outputs of a physical system by explicit functions. This methodology has been widely employed in many applications such as design optimization, response prediction and model validation. But so far the literature related to its application in structural damage identification (SDI) is scarce. Therefore this study attempts to present a systematic SDI procedure comprising four sequential steps of feature selection, parameter screening, primary response surface (RS) modeling and updating, and reference-state RS modeling with SDI realization using the factorial design (FD) and the central composite design (CCD). The last two steps imply the implementation of inverse problems by model updating in which the RS models substitute the FE models. The proposed method was verified against a numerical beam, a tested reinforced concrete (RC) frame and an experimental full-scale bridge with the modal frequency being the output responses. It was found that the proposed RSM-based method performs well in predicting the damage of both numerical and experimental structures having single and multiple damage scenarios. The screening capacity of the FD can provide quantitative estimation of the significance levels of updating parameters. Meanwhile, the second-order polynomial model established by the CCD provides adequate accuracy in expressing the dynamic behavior of a physical system.

A three-dimensional `Kaiser damage-memory' effect through true-triaxial loading

NASA Astrophysics Data System (ADS)

Meredith, P. G.; Browning, J.; Harland, S. R.; Healy, D.; Stuart, C.; Mitchell, T. M.

2017-12-01

Microcrack damage leading to failure in rocks evolves in response to differential loading. The vast majority of experimental studies investigate damage evolution, the `Kaiser damage-memory' effect, and rock failure using conventional triaxial stress states (σ1 > σ2 = σ3). Such stress states develop a crack population that displays cylindrical transverse isotropy. However, in nature the stress state is in general truly triaxial (σ1 > σ2 > σ3) and experiments that utilise such loading conditions can generate crack populations that display planar transverse isotropy which in turn influences properties such as permeability and strength. We investigate the evolution of crack damage under both conventional and true triaxial stress conditions using results from measurements made on cubic samples of sandstone deformed in three orthogonal directions with independently controlled stress paths. We have measured, simultaneously with stress and strain, the changes in ultrasonic compressional and shear wave velocities in the three principal directions, together with the bulk acoustic emission (AE) output. Changes in acoustic wave velocities are associated with both elastic closure and opening of pre-existing cracks, and the inelastic formation of new cracks. By contrast, AE is only associated with the inelastic growth of new crack damage and as such, we use the onset of AE to determine the initiation of new crack damage. By mapping these damage onsets under both conventional triaxial and true triaxial sequential cyclic loading, we have shown that `damage envelopes' evolve dynamically and can be pushed closer to the failure envelope. Whether a stress state has been `visited' before is key to determining and understanding damage states. Crack damage populations can be generated with multiple orientations depending on the arrangement of loading directions and hence principal stress directions. The sequential cyclic loading tests show that further damage in any one population commences only when the previous maximum differential stress `seen' by that population is exceeded. Understanding anisotropic damage is important for applying the results of true-triaxial tests and hence better replicating natural fractured systems.

The United States should forego a damage-limitation capability against China

NASA Astrophysics Data System (ADS)

Glaser, Charles L.

2017-11-01

Bottom Lines • THE KEY STRATEGIC NUCLEAR CHOICE. Whether to attempt to preserve its damage-limitation capability against China is the key strategic nuclear choice facing the United States. The answer is much less clear-cut than when the United States faced the Soviet Union during the Cold War. • FEASIBILITY OF DAMAGE LIMITATION. Although technology has advanced significantly over the past three decades, future military competition between the U.S. and Chinese forces will favor large-scale nuclear retaliation over significant damage limitation. • BENEFITS AND RISKS OF A DAMAGE-LIMITATION CAPABILITY. The benefits provided by a modest damage-limitation capability would be small, because the United States can meet its most important regional deterrent requirements without one. In comparison, the risks, which include an increased probability of accidental and unauthorized Chinese attacks, as well as strained U.S.—China relations, would be large. • FOREGO DAMAGE LIMITATION. These twin findings—the poor prospects for prevailing in the military competition, and the small benefits and likely overall decrease in U.S. security—call for a U.S. policy that foregoes efforts to preserve or enhance its damage-limitation capability.

Solar UVB-induced DNA damage and photoenzymatic DNA repair in antarctic zooplankton

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

Malloy, K.D.; Holman, M.A.; Mitchell, D.

The detrimental effects of elevated intensities of mid-UV radiation (UVB), a result of stratospheric ozone depletion during the austral spring, on the primary producers of the Antarctic marine ecosystem have been well documented. Here we report that natural populations of Antarctic zooplankton also sustain significant DNA damage [measured as cyclobutane pyrimidine dimers (CPDs)] during periods of increased UVB flux. This is the first direct evidence that increased solar UVB may result in damage to marine organisms other than primary producers in Antarctica. The extent of DNA damage in pelagic icefish eggs correlated with daily incident UVB irradiance, reflecting the differencemore » between acquisition and repair of CPDs. Patterns of DNA damage in fish larvae did not correlated with daily UVB flux, possibly due to different depth distributions and/or different capacities for DNA repair. Clearance of CPDs by Antarctic fish and krill was mediated primarily by the photoenzymatic repair system. Although repair rates were large for all species evaluated, they were apparently inadequate to prevent the transient accumulation of substantial CPD burdens. The capacity for DNA repair in Antarctic organisms was highest in those species whose early life history stages occupy the water column during periods of ozone depletion (austral spring) and lowest in fish species whose eggs and larvae are abundant during winter. Although the potential reduction in fitness of Antarctic zooplankton resulting from DNA damage is unknown, we suggest that increased solar UV may reduce recruitment and adversely affect trophic transfer of productivity by affecting heterotrophic species as well as primary producers. 54 refs., 4 figs., 2 tabs.« less

Acute Doxorubicin Insult in the Mouse Ovary Is Cell- and Follicle-Type Dependent

PubMed Central

Roti Roti, Elon C.; Leisman, Scott K.; Abbott, David H.; Salih, Sana M.

2012-01-01

Primary ovarian insufficiency (POI) is one of the many unintended consequences of chemotherapy faced by the growing number of female cancer survivors. While ovarian repercussions of chemotherapy have long been recognized, the acute insult phase and primary sites of damage are not well-studied, hampering efforts to design effective intervention therapies to protect the ovary. Utilizing doxorubicin (DXR) as a model chemotherapy agent, we defined the acute timeline for drug accumulation, induced DNA damage, and subsequent cellular and follicular demise in the mouse ovary. DXR accumulated first in the core ovarian stroma cells, then redistributed outwards into the cortex and follicles in a time-dependent manner, without further increase in total ovarian drug levels after four hours post-injection. Consistent with early drug accumulation and intimate interactions with the blood supply, stroma cell-enriched populations exhibited an earlier DNA damage response (measurable at 2 hours) than granulosa cells (measurable at 4 hours), as quantified by the comet assay. Granulosa cell-enriched populations were more sensitive however, responding with greater levels of DNA damage. The oocyte DNA damage response was delayed, and not measurable above background until 10–12 hours post-DXR injection. By 8 hours post-DXR injection and prior to the oocyte DNA damage response, the number of primary, secondary, and antral follicles exhibiting TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling)-positive granulosa cells plateaued, indicating late-stage apoptosis and suggesting damage to the oocytes is subsequent to somatic cell failure. Primordial follicles accumulate significant DXR by 4 hours post-injection, but do not exhibit TUNEL-positive granulosa cells until 48 hours post-injection, indicating delayed demise. Taken together, the data suggest effective intervention therapies designed to protect the ovary from chemotherapy accumulation and induced insult in the ovary must act almost immediately to prevent acute insult as significant damage was seen in stroma cells within the first two hours. PMID:22876313

Seismic damage identification for steel structures using distributed fiber optics.

PubMed

Hou, Shuang; Cai, C S; Ou, Jinping

2009-08-01

A distributed fiber optic monitoring methodology based on optic time domain reflectometry technology is developed for seismic damage identification of steel structures. Epoxy with a strength closely associated to a specified structure damage state is used for bonding zigzagged configured optic fibers on the surfaces of the structure. Sensing the local deformation of the structure, the epoxy modulates the signal change within the optic fiber in response to the damage state of the structure. A monotonic loading test is conducted on a steel specimen installed with the proposed sensing system using selected epoxy that will crack at the designated strain level, which indicates the damage of the steel structure. Then, using the selected epoxy, a varying degree of cyclic loading amplitudes, which is associated with different damage states, is applied on a second specimen. The test results show that the specimen's damage can be identified by the optic sensors, and its maximum local deformation can be recorded by the sensing system; moreover, the damage evolution can also be identified.

Reversine-treated fibroblasts acquire myogenic competence in vitro and in regenerating skeletal muscle.

PubMed

Anastasia, Luigi; Sampaolesi, Maurilio; Papini, Nadia; Oleari, Diego; Lamorte, Giuseppe; Tringali, Cristina; Monti, Eugenio; Galli, Daniela; Tettamanti, Guido; Cossu, Giulio; Venerando, Bruno

2006-12-01

Stem cells hold a great potential for the regeneration of damaged tissues in cardiovascular or musculoskeletal diseases. Unfortunately, problems such as limited availability, control of cell fate, and allograft rejection need to be addressed before therapeutic applications may become feasible. Generation of multipotent progenitors from adult differentiated cells could be a very attractive alternative to the limited in vitro self-renewal of several types of stem cells. In this direction, a recently synthesized unnatural purine, named reversine, has been proposed to induce reversion of adult cells to a multipotent state, which could be then converted into other cell types under appropriate stimuli. Our study suggests that reversine treatment transforms primary murine and human dermal fibroblasts into myogenic-competent cells both in vitro and in vivo. Moreover, this is the first study to demonstrate that plasticity changes arise in primary mouse and human cells following reversine exposure.

Distributed Damage Estimation for Prognostics based on Structural Model Decomposition

NASA Technical Reports Server (NTRS)

Daigle, Matthew; Bregon, Anibal; Roychoudhury, Indranil

2011-01-01

Model-based prognostics approaches capture system knowledge in the form of physics-based models of components, and how they fail. These methods consist of a damage estimation phase, in which the health state of a component is estimated, and a prediction phase, in which the health state is projected forward in time to determine end of life. However, the damage estimation problem is often multi-dimensional and computationally intensive. We propose a model decomposition approach adapted from the diagnosis community, called possible conflicts, in order to both improve the computational efficiency of damage estimation, and formulate a damage estimation approach that is inherently distributed. Local state estimates are combined into a global state estimate from which prediction is performed. Using a centrifugal pump as a case study, we perform a number of simulation-based experiments to demonstrate the approach.

Paraheliotropic leaf movement in Siratro as a protective mechanism against drought-induced damage to primary photosynthetic reactions: damage by excessive light and heat.

PubMed

Ludlow, M M; Björkman, O

1984-11-01

Damage to primary photosynthetic reactions by drought, excess light and heat in leaves of Macroptilium atropurpureum Dc. cv. Siratro was assessed by measurements of chlorophyll fluorescence emission kinetics at 77 K (-196°C). Paraheliotropic leaf movement protected waterstressed Siratro leaves from damage by excess light (photoinhibition), by heat, and by the interactive effects of excess light and high leaf temperatures. When the leaves were restrained to a horizontal position, photoinhibition occurred and the degree of photoinhibitory damage increased with the time of exposure to high levels of solar radiation. Severe inhibition was followed by leaf death, but leaves gradually recovered from moderate damage. This drought-induced photoinhibitory damage seemed more closely related to low leaf water potential than to low leaf conductance. Exposure to leaf temperatures above 42°C caused damage to the photosynthetic system even in the dark and leaves died at 48°C. Between 42 and 48°C the degree of heat damage increased with the time of exposure, but recovery from moderate heat damage occurred over several days. The threshold temperature for direct heat damage increased with the growth temperature regime, but was unaffected by water-stress history or by current leaf water status. No direct heat damage occurred below 42°C, but in water-stressed plants photoinhibition increased with increasing leaf temperature in the range 31-42°C and with increasing photon flux density up to full sunglight values. Thus, water stress evidently predisposes the photosynthetic system to photoinhibition and high leaf temperature exacerbates this photoinhibitory damage. It seems probable that, under the climatic conditions where Siratro occurs in nature, but in the absence of paraheliotropic leaf movement, photoinhibitory damage would occur more frequently during drought than would direct heat damage.

Estimating monetary damages from flooding in the United States under a changing climate

EPA Science Inventory

A national-scale analysis of potential changes in monetary damages from flooding under climate change. The approach uses empirically based statistical relationships between historical precipitation and flood damage records from 18 hydrologic regions of the United States, along w...

Computational Implementation of a Thermodynamically Based Work Potential Model For Progressive Microdamage and Transverse Cracking in Fiber-Reinforced Laminates

NASA Technical Reports Server (NTRS)

Pineda, Evan J.; Waas, Anthony M.; Bednarcyk, Brett A.; Collier, Craig S.

2012-01-01

A continuum-level, dual internal state variable, thermodynamically based, work potential model, Schapery Theory, is used capture the effects of two matrix damage mechanisms in a fiber-reinforced laminated composite: microdamage and transverse cracking. Matrix microdamage accrues primarily in the form of shear microcracks between the fibers of the composite. Whereas, larger transverse matrix cracks typically span the thickness of a lamina and run parallel to the fibers. Schapery Theory uses the energy potential required to advance structural changes, associated with the damage mechanisms, to govern damage growth through a set of internal state variables. These state variables are used to quantify the stiffness degradation resulting from damage growth. The transverse and shear stiffness of the lamina are related to the internal state variables through a set of measurable damage functions. Additionally, the damage variables for a given strain state can be calculated from a set of evolution equations. These evolution equations and damage functions are implemented into the finite element method and used to govern the constitutive response of the material points in the model. Additionally, an axial failure criterion is included in the model. The response of a center-notched, buffer strip-stiffened panel subjected to uniaxial tension is investigated and results are compared to experiment.

The US Medical Liability System: Evidence for Legislative Reform

PubMed Central

Guirguis-Blake, Janelle; Fryer, George E.; Phillips, Robert L.; Szabat, Ronald; Green, Larry A.

2006-01-01

BACKGROUND Despite state and federal efforts to implement medical malpractice reform, there is limited evidence on which to base policy decisions. The National Practitioner Data Bank (NPDB) offers an opportunity to evaluate the effects of previous malpractice tort reforms on malpractice payments and premiums. METHODS For every state and the District of Columbia, we calculated the number of malpractice payments, total amount paid, and average payment from NPDB data reported from 1999 through 2001. We analyzed 44,913 claims using logistic regression to study associations between payments, physician premiums, and 10 state statutory tort reforms. RESULTS Wide variations exist in malpractice payments among states. The reforms most associated with lower payments and premiums were total and noneconomic damage caps. Mean payments were 26% lower in states with total damage caps ($196,495.34 vs $265,554.50, P = .001). Mean payments were 22% less in states with noneconomic damage caps ($219,225.98 vs $279,849.86, P = .010). Total damage caps were associated with lower mean annual premiums, especially for obstetricians ($22,371.57 vs $42,728.68, P <.001). Hard noneconomic damage caps were associated with premium reductions for obstetricians (30,283.75 vs 45,740.88; P = .039). CONCLUSIONS Significant reductions in malpractice payments could be realized if total or noneconomic damage caps were operating nationally. Hard noneconomic damage and total damage caps could yield lower premiums. If tied to a comprehensive plan for reform, the money saved could be diverted to implement alternative approaches to patient compensation or be used to achieve other systems reform benefiting patients, employers, physicians, and hospitals. PMID:16735526

The US Medical Liability System: evidence for legislative reform.

PubMed

Guirguis-Blake, Janelle; Fryer, George E; Phillips, Robert L; Szabat, Ronald; Green, Larry A

2006-01-01

Despite state and federal efforts to implement medical malpractice reform, there is limited evidence on which to base policy decisions. The National Practitioner Data Bank (NPDB) offers an opportunity to evaluate the effects of previous malpractice tort reforms on malpractice payments and premiums. For every state and the District of Columbia, we calculated the number of malpractice payments, total amount paid, and average payment from NPDB data reported from 1999 through 2001. We analyzed 44,913 claims using logistic regression to study associations between payments, physician premiums, and 10 state statutory tort reforms. Wide variations exist in malpractice payments among states. The reforms most associated with lower payments and premiums were total and noneconomic damage caps. Mean payments were 26% lower in states with total damage caps (196,495.34 dollars vs 265,554.50 dollars, P = .001). Mean payments were 22% less in states with noneconomic damage caps (219,225.98 dollars vs 279,849.86 dollars, P = .010). Total damage caps were associated with lower mean annual premiums, especially for obstetricians (22,371.57 dollars vs 42,728.68 dollars, P <.001). Hard noneconomic damage caps were associated with premium reductions for obstetricians (30,283.75 vs 45,740.88; P = .039). Significant reductions in malpractice payments could be realized if total or noneconomic damage caps were operating nationally. Hard noneconomic damage and total damage caps could yield lower premiums. If tied to a comprehensive plan for reform, the money saved could be diverted to implement alternative approaches to patient compensation or be used to achieve other systems reform benefiting patients, employers, physicians, and hospitals.

A novel regulation mechanism of DNA repair by damage-induced and RAD23-dependent stabilization of xeroderma pigmentosum group C protein

PubMed Central

Ng, Jessica M.Y.; Vermeulen, Wim; van der Horst, Gijsbertus T.J.; Bergink, Steven; Sugasawa, Kaoru; Vrieling, Harry; Hoeijmakers, Jan H.J.

2003-01-01

Primary DNA damage sensing in mammalian global genome nucleotide excision repair (GG-NER) is performed by the xeroderma pigmentosum group C (XPC)/HR23B protein complex. HR23B and HR23A are human homologs of the yeast ubiquitin-domain repair factor RAD23, the function of which is unknown. Knockout mice revealed that mHR23A and mHR23B have a fully redundant role in NER, and a partially redundant function in embryonic development. Inactivation of both genes causes embryonic lethality, but appeared still compatible with cellular viability. Analysis of mHR23A/B double-mutant cells showed that HR23 proteins function in NER by governing XPC stability via partial protection against proteasomal degradation. Interestingly, NER-type DNA damage further stabilizes XPC and thereby enhances repair. These findings resolve the primary function of RAD23 in repair and reveal a novel DNA-damage-dependent regulation mechanism of DNA repair in eukaryotes, which may be part of a more global damage-response circuitry. PMID:12815074

Different neural correlates of facing pain with mindfulness: Contributions of strategy and skill. Comment on “Facing the experience of pain: A neuropsychological perspective” by Fabbro and Crescentini

NASA Astrophysics Data System (ADS)

Gard, Tim

2014-09-01

As Fabbro and Crescentini [1] state at the beginning of their perspective article, pain is an inevitable, complex and multifaceted phenomenon. While acute pain fulfills an important alerting function, persistent pain is considered maladaptive and associated with unnecessary suffering. The definition of pain "an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage" indicates the presence of sensory and emotional components [2]. In the brain the sensory aspects of pain, or its intensity, is associated with activations in primary and secondary somatosensory cortex while the emotional aspects of pain or pain unpleasantness are related to brain activation in dorsal anterior cingulate cortex [3,4]. Physical and emotional pain have overlapping mechanisms [5,6] as Fabbro and Crescentini [1] discuss with respect to social exclusion, empathy and the pain of separation including the fear of death.

Fragmentation of displacement cascades into subcascades: A molecular dynamics study

DOE PAGES

Antoshchenkova, E.; Luneville, L.; Simeone, D.; ...

2014-12-12

The fragmentation of displacement cascades into subcascades in copper and iron has been investigated through the molecular dynamics technique. A two-point density correlation function has been used to analyze the cascades as a function of the primary knock-on (PKA) energy. This approach is used as a tool for detecting subcascade formation. The fragmentation can already be identified at the end of the ballistic phase. Its resulting evolution in the peak damage state discriminates between unconnected and connected subcascades. The damage zone at the end of the ballistic phase is the precursor of the extended regions that contain the surviving defects.more » A fractal analysis of the cascade exhibits a dependence on both the stage of the cascade development and the PKA energy. This type of analysis enables the minimum and maximum displacement spike energies together with the subcascade formation threshold energy to be determined. (C) 2014 Elsevier B.V. All rights reserved.« less

Fragmentation of displacement cascades into subcascades: A molecular dynamics study

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

Antoshchenkova, E.; Luneville, L.; Simeone, D.

The fragmentation of displacement cascades into subcascades in copper and iron has been investigated through the molecular dynamics technique. A two-point density correlation function has been used to analyze the cascades as a function of the primary knock-on (PKA) energy. This approach is used as a tool for detecting subcascade formation. The fragmentation can already be identified at the end of the ballistic phase. Its resulting evolution in the peak damage state discriminates between unconnected and connected subcascades. The damage zone at the end of the ballistic phase is the precursor of the extended regions that contain the surviving defects.more » A fractal analysis of the cascade exhibits a dependence on both the stage of the cascade development and the PKA energy. This type of analysis enables the minimum and maximum displacement spike energies together with the subcascade formation threshold energy to be determined. (C) 2014 Elsevier B.V. All rights reserved.« less

Urinary markers of renal damage in hypertensive children diagnosed with ambulatory blood pressure monitoring.

PubMed

Girişgen, İlknur; Sönmez, Ferah; Yenisey, Ciğdem; Kurt-Omurlu, İmran

2014-01-01

Primary hypertension is the most important risk factor for chronic kidney disease in adulthood. However, the role of hypertension in kidney damage in childhood is not known exactly. The aim of this study was to evaluate the ambulatory blood pressure measurements of healthy children diagnosed as hypertensive with routine office blood pressure monitoring and to investigate the effects of primary hypertension on the kidney. Fifty-six patients who had blood pressure higher than 90th percentile during their well-child follow-up and 27 healthy children with normal blood pressure were included in the study. Twenty-four hour blood pressure measurements were recorded for all the patients. Microalbumin and N-acetyl-β-D-glucosaminidase (NAG) levels in the 24-hour urine were determined in the study groups. According to the results of ambulatory blood pressure measurements, 52% of the patients were diagnosed as white coat hypertension. The patients and the white coat hypertensive group had higher levels of urinary NAG than the control group. No significant difference was found in the levels of urinary microalbumin excretion between the primary hypertension and control groups. It was thought that ambulatory blood pressure measurement was necessary for the true diagnosis of hypertension in children, and further, that primary and white coat hypertension had effects on kidney damage in childhood. It is suggested that urine NAG excretion might be used as an early sign of hypertension-induced renal damage.

Evaluation of deterioration of structural concrete due to chloride intrusion and other damaging mechanisms.

DOT National Transportation Integrated Search

2015-09-01

Kentucky's bridges continue to age and experience distress. The intrusion of chlorides into : concrete remains the primary mechanism for deterioration. It leads to reinforcing steel corrosion : that damages the adjoining concrete structure. This stud...

Damage by Tibraca limbativentris Stål (Pentatomidae) to Upland Rice Cultivated in Amazon Rainforest Region (Brazil) at Different Growth Stages.

PubMed

Krinski, D; Foerster, L A

2017-02-01

In this study, we evaluated the damage caused in the field by Tibraca limbativentris Stål adults at different levels of infestation (0, 1, 2, and 4 stink bugs) per three rice plants during three growth stages (V8, V13, and R4 stages) of upland rice cultivated in southwestern of Pará State, Amazon Rainforest region, Brazil. Heading time (panicle exertion) was affected by T. limbativentris infestations mainly in the vegetative stage and the whiteheads percentage in treatments ranged from 18.2 to 38%. The dead hearts percentages varied between 0 and 21.5%, and the mean number of primary branches (ramifications) ranged from 5.9 ± 0.4 to 12.3 ± 0.2. The number of empty spikelets was only affected in infestations with four insects/three plants, while the quantity of filled grains per panicle was affected only when infestations occurred during the vegetative stage. The total number of spikelets (filled + empty) per panicle decreased significantly in all phenological stages, and the percentage of damage ranged from 17 to 44% among treatments. Based on the proportion of damage observed, we suggest doubling the number of insects presently used as action threshold to 2 and 4 stink bugs per 15 stalks sampled for the vegetative stage, and of 1 or 2 stink bugs per 15 stalks sampled at the beginning of reproductive stage (R3/R4). Also, the field should be monitored during the entire vegetative stage, since most damage was observed in this phenological stage.

Fuel containment and damage tolerance for large composite primary aircraft structures. Phase 1: Testing

NASA Technical Reports Server (NTRS)

Sandifer, J. P.

1983-01-01

Technical problems associated with fuel containment and damage tolerance of composite material wings for transport aircraft were identified. The major tasks are the following: (1) the preliminary design of damage tolerant wing surface using composite materials; (2) the evaluation of fuel sealing and lightning protection methods for a composite material wing; and (3) an experimental investigation of the damage tolerant characteristics of toughened resin graphite/epoxy materials. The test results, the test techniques, and the test data are presented.

Ultrashort Laser Retinal Damage Threshold Mechanisms

DTIC Science & Technology

2010-01-15

epithelium . Below one nanosecond both stress-confinement in melanosomes and self-focusing reduce the threshold for damage as measured in corneal radiant... epithelium (RPE). Below 1 ns, both stress confinement in melanosomes and self-focusing reduce the threshold for damage as measured in corneal radiant...collimated laser light is focused to a very small spot on the retina. The retinal pigment epithelium (RPE) contains melanosomes, which are the primary

Molecular dynamics simulations of the structure evolutions of Cu-Zr metallic glasses under irradiation

NASA Astrophysics Data System (ADS)

Lang, Lin; Tian, Zean; Xiao, Shifang; Deng, Huiqiu; Ao, Bingyun; Chen, Piheng; Hu, Wangyu

2017-02-01

Molecular dynamics simulations have been performed to investigate the structural evolution of Cu64.5Zr35.5 metallic glasses under irradiation. The largest standard cluster analysis (LSCA) method was used to quantify the microstructure within the collision cascade regions. It is found that the majority of clusters within the collision cascade regions are full and defective icosahedrons. Not only the smaller structures (common neighbor subcluster) but also primary clusters greatly changed during the collision cascades; while most of these radiation damages self-recover quickly in the following quench states. These findings indicate the Cu-Zr metallic glasses have excellent irradiation-resistance properties.

Structural damage detection using deep learning of ultrasonic guided waves

NASA Astrophysics Data System (ADS)

Melville, Joseph; Alguri, K. Supreet; Deemer, Chris; Harley, Joel B.

2018-04-01

Structural health monitoring using ultrasonic guided waves relies on accurate interpretation of guided wave propagation to distinguish damage state indicators. However, traditional physics based models do not provide an accurate representation, and classic data driven techniques, such as a support vector machine, are too simplistic to capture the complex nature of ultrasonic guide waves. To address this challenge, this paper uses a deep learning interpretation of ultrasonic guided waves to achieve fast, accurate, and automated structural damaged detection. To achieve this, full wavefield scans of thin metal plates are used, half from the undamaged state and half from the damaged state. This data is used to train our deep network to predict the damage state of a plate with 99.98% accuracy given signals from just 10 spatial locations on the plate, as compared to that of a support vector machine (SVM), which achieved a 62% accuracy.

Treatment of leprosy/Hansen's disease in the early 21st century.

PubMed

Worobec, Sophie M

2009-01-01

Leprosy, or Hansen's disease (HD), is caused by Mycobacterium leprae, a slowly dividing mycobacterium that has evolved to be an intracellular parasite, causing skin lesions and nerve damage. Less than 5% of people exposed to M. leprae develop clinical disease. Host cell-mediated resistance determines whether an individual will develop paucibacillary or multibacillary disease. Hansen's disease is a worldwide disease with about 150 new cases reported annually in the United States. Effective anti-mycobacterial treatments are available, and many patients experience severe reversal and erythema nodosum leprosum reactions that also require treatment. Leprosy has been the target of a World Health Organization multiple drug therapy campaign to eliminate it as a national public health problem in member countries, but endemic regions persist. In the United States, the National Hansen's Disease Program has primary responsibility for medical care, research, and information.

Biaxial stress relaxation of semilunar heart valve leaflets during simulated collagen catabolism: Effects of collagenase concentration and equibiaxial strain state.

PubMed

Huang, Siyao; Huang, Hsiao-Ying Shadow

2015-10-01

Heart valve leaflet collagen turnover and remodeling are innate to physiological homeostasis; valvular interstitial cells routinely catabolize damaged collagen and affect repair. Moreover, evidence indicates that leaflets can adapt to altered physiological (e.g. pregnancy) and pathological (e.g. hypertension) mechanical load states, tuning collagen structure and composition to changes in pressure and flow. However, while valvular interstitial cell-secreted matrix metalloproteinases are considered the primary effectors of collagen catabolism, the mechanisms by which damaged collagen fibers are selectively degraded remain unclear. Growing evidence suggests that the collagen fiber strain state plays a key role, with the strain-dependent configuration of the collagen molecules either masking or presenting proteolytic sites, thereby protecting or accelerating collagen proteolysis. In this study, the effects of equibiaxial strain state on collagen catabolism were investigated in porcine aortic valve and pulmonary valve tissues. Bacterial collagenase (0.2 and 0.5 mg/mL) was utilized to simulate endogenous matrix metalloproteinases, and biaxial stress relaxation and biochemical collagen concentration served as functional and compositional measures of collagen catabolism, respectively. At a collagenase concentration of 0.5 mg/mL, increasing the equibiaxial strain imposed during stress relaxation (0%, 37.5%, and 50%) yielded significantly lower median collagen concentrations in the aortic valve (p = 0.0231) and pulmonary valve (p = 0.0183), suggesting that relatively large strain magnitudes may enhance collagen catabolism. Collagen concentration decreases were paralleled by trends of accelerated normalized stress relaxation rate with equibiaxial strain in aortic valve tissues. Collectively, these in vitro results indicate that biaxial strain state is capable of affecting the susceptibility of valvular collagens to catabolism, providing a basis for further investigation of how such phenomena may manifest at different strain magnitudes or in vivo. © IMechE 2015.

Localized grey matter damage in early primary progressive multiple sclerosis contributes to disability.

PubMed

Khaleeli, Z; Cercignani, M; Audoin, B; Ciccarelli, O; Miller, D H; Thompson, A J

2007-08-01

Disability in primary progressive multiple sclerosis (PPMS) has been correlated with damage to the normal appearing brain tissues. Magnetization transfer ratio (MTR) and volume changes indicate that much of this damage occurs in the normal appearing grey matter, but the clinical significance of this remains uncertain. We aimed to localize these changes to distinct grey matter regions, and investigate the clinical impact of the MTR changes. 46 patients with early PPMS and 23 controls underwent MT and high-resolution T1-weighted imaging. Patients were scored on the Expanded Disability Status Scale (EDSS), Multiple Sclerosis Functional Composite and subtests (Nine-Hole Peg Test, Timed Walk Test, Paced Auditory Serial Addition Test [PASAT]). Grey matter volume and MTR were compared between patients and controls, adjusting for age. Mean MTR for significant regions within the motor network and in areas relevant to PASAT performance were correlated with appropriate clinical scores, adjusting for grey matter volume. Patients showed reduced MTR and atrophy in the right pre- and left post-central gyri, right middle frontal gyrus, left insula, and thalamus bilaterally. Reduced MTR without significant atrophy occurred in the left pre-central gyrus, left superior frontal gyri, bilateral superior temporal gyri, right insula and visual cortex. Higher EDSS correlated with lower MTR in the right primary motor cortex (BA 4). In conclusion, localized grey matter damage occurs in early PPMS, and MTR change is more widespread than atrophy. Damage demonstrated by reduced MTR is clinically eloquent.

Investigation of the effects of sliding on wheel tread damage

DOT National Transportation Integrated Search

2005-11-05

Wheel tread spalling is the main source of damage to wheel treads and : a primary cause for wheel removals from service. Severe frictional : heating of the wheel-rail contact patch during sliding causes the : formation of martensite, a hard, brittle ...

NaHS Protects against the Impairments Induced by Oxygen-Glucose Deprivation in Different Ages of Primary Hippocampal Neurons

PubMed Central

Yu, Qian; Wang, Binrong; Zhao, Tianzhi; Zhang, Xiangnan; Tao, Lei; Shi, Jinshan; Sun, Xude; Ding, Qian

2017-01-01

Brain ischemia leads to poor oxygen supply, and is one of the leading causes of brain damage and/or death. Neuroprotective agents are thus in great need for treatment purpose. Using both young and aged primary cultured hippocampal neurons as in vitro models, we investigated the effect of sodium hydrosulfide (NaHS), an exogenous donor of hydrogen sulfide, on oxygen-glucose deprivation (OGD) damaged neurons that mimick focal cerebral ischemia/reperfusion (I/R) induced brain injury. NaHS treatment (250 μM) protected both young and aged hippocampal neurons, as indicated by restoring number of primary dendrites by 43.9 and 68.7%, number of dendritic end tips by 59.8 and 101.1%, neurite length by 36.8 and 66.7%, and spine density by 38.0 and 58.5% in the OGD-damaged young and aged neurons, respectively. NaHS treatment inhibited growth-associated protein 43 downregulation, oxidative stress in both young and aged hippocampal neurons following OGD damage. Further studies revealed that NaHS treatment could restore ERK1/2 activation, which was inhibited by OGD-induced protein phosphatase 2 (PP2A) upregulation. Our results demonstrated that NaHS has potent protective effects against neuron injury induced by OGD in both young and aged hippocampal neurons. PMID:28326019

[Reccurent mycobacterial diseases in patients with impaired axis IL-12/INF-gamma].

PubMed

Strach, Magdalena; Nalepa, Piotr; Sulicka-Grodzicka, Joanna; Kierzkowska, Izabella; Siedlar, Maciej; Grodzicki, Tomasz

2013-01-01

Mycobacteria is a large group of pathogens that are common in environment, in soil and tap water. Although mycobacteria [non tuberculosis mycobacteria] can inhabit body surface without causing any disease in the circumstances of primary or secondary immunodeficiency can cause clinically significant organ or systemic damage. Defect of IL-12/INFgamma axis is an example of primary immunodeficiency that predispose to mycobacterial infections while protection against other microorganisms is not damaged. We present review of known defects of IL-12/IFNgamma axis and brief presentation of our own experience.

Focal temporal pole atrophy and network degeneration in semantic variant primary progressive aphasia

PubMed Central

Collins, Jessica A; Montal, Victor; Hochberg, Daisy; Quimby, Megan; Mandelli, Maria Luisa; Makris, Nikos; Seeley, William W; Gorno-Tempini, Maria Luisa; Dickerson, Bradford C

2017-01-01

Abstract A wealth of neuroimaging research has associated semantic variant primary progressive aphasia with distributed cortical atrophy that is most prominent in the left anterior temporal cortex; however, there is little consensus regarding which region within the anterior temporal cortex is most prominently damaged, which may indicate the putative origin of neurodegeneration. In this study, we localized the most prominent and consistent region of atrophy in semantic variant primary progressive aphasia using cortical thickness analysis in two independent patient samples (n = 16 and 28, respectively) relative to age-matched controls (n = 30). Across both samples the point of maximal atrophy was located in the same region of the left temporal pole. This same region was the point of maximal atrophy in 100% of individual patients in both semantic variant primary progressive aphasia samples. Using resting state functional connectivity in healthy young adults (n = 89), we showed that the seed region derived from the semantic variant primary progressive aphasia analysis was strongly connected with a large-scale network that closely resembled the distributed atrophy pattern in semantic variant primary progressive aphasia. In both patient samples, the magnitude of atrophy within a brain region was predicted by that region’s strength of functional connectivity to the temporopolar seed region in healthy adults. These findings suggest that cortical atrophy in semantic variant primary progressive aphasia may follow connectional pathways within a large-scale network that converges on the temporal pole. PMID:28040670

"No Longer Gage": Frontal Lobe Dysfunction and Emotional Changes.

ERIC Educational Resources Information Center

Stuss, Donald T.; And Others

1992-01-01

Reviews changes in emotional response and personality occurring after damage to frontal systems, proposes operational definitions, and analyzes reports according to these definitions. Summarizes neurological causes of frontal lobe damage and associations of frontal dysfunction with psychiatric disturbances. Proposes that primary change after…

Serine is the major residue for ADP-ribosylation upon DNA damage

PubMed Central

Dauben, Helen

2018-01-01

Poly(ADP-ribose) polymerases (PARPs) are a family of enzymes that synthesise ADP-ribosylation (ADPr), a reversible modification of proteins that regulates many different cellular processes. Several mammalian PARPs are known to regulate the DNA damage response, but it is not clear which amino acids in proteins are the primary ADPr targets. Previously, we reported that ARH3 reverses the newly discovered type of ADPr (ADPr on serine residues; Ser-ADPr) and developed tools to analyse this modification (Fontana et al., 2017). Here, we show that Ser-ADPr represents the major fraction of ADPr synthesised after DNA damage in mammalian cells and that globally Ser-ADPr is dependent on HPF1, PARP1 and ARH3. In the absence of HPF1, glutamate/aspartate becomes the main target residues for ADPr. Furthermore, we describe a method for site-specific validation of serine ADP-ribosylated substrates in cells. Our study establishes serine as the primary form of ADPr in DNA damage signalling. PMID:29480802

Continuum theory of fibrous tissue damage mechanics using bond kinetics: application to cartilage tissue engineering.

PubMed

Nims, Robert J; Durney, Krista M; Cigan, Alexander D; Dusséaux, Antoine; Hung, Clark T; Ateshian, Gerard A

2016-02-06

This study presents a damage mechanics framework that employs observable state variables to describe damage in isotropic or anisotropic fibrous tissues. In this mixture theory framework, damage is tracked by the mass fraction of bonds that have broken. Anisotropic damage is subsumed in the assumption that multiple bond species may coexist in a material, each having its own damage behaviour. This approach recovers the classical damage mechanics formulation for isotropic materials, but does not appeal to a tensorial damage measure for anisotropic materials. In contrast with the classical approach, the use of observable state variables for damage allows direct comparison of model predictions to experimental damage measures, such as biochemical assays or Raman spectroscopy. Investigations of damage in discrete fibre distributions demonstrate that the resilience to damage increases with the number of fibre bundles; idealizing fibrous tissues using continuous fibre distribution models precludes the modelling of damage. This damage framework was used to test and validate the hypothesis that growth of cartilage constructs can lead to damage of the synthesized collagen matrix due to excessive swelling caused by synthesized glycosaminoglycans. Therefore, alternative strategies must be implemented in tissue engineering studies to prevent collagen damage during the growth process.

Continuum theory of fibrous tissue damage mechanics using bond kinetics: application to cartilage tissue engineering

PubMed Central

Nims, Robert J.; Durney, Krista M.; Cigan, Alexander D.; Hung, Clark T.; Ateshian, Gerard A.

2016-01-01

This study presents a damage mechanics framework that employs observable state variables to describe damage in isotropic or anisotropic fibrous tissues. In this mixture theory framework, damage is tracked by the mass fraction of bonds that have broken. Anisotropic damage is subsumed in the assumption that multiple bond species may coexist in a material, each having its own damage behaviour. This approach recovers the classical damage mechanics formulation for isotropic materials, but does not appeal to a tensorial damage measure for anisotropic materials. In contrast with the classical approach, the use of observable state variables for damage allows direct comparison of model predictions to experimental damage measures, such as biochemical assays or Raman spectroscopy. Investigations of damage in discrete fibre distributions demonstrate that the resilience to damage increases with the number of fibre bundles; idealizing fibrous tissues using continuous fibre distribution models precludes the modelling of damage. This damage framework was used to test and validate the hypothesis that growth of cartilage constructs can lead to damage of the synthesized collagen matrix due to excessive swelling caused by synthesized glycosaminoglycans. Therefore, alternative strategies must be implemented in tissue engineering studies to prevent collagen damage during the growth process. PMID:26855751

Material State Awareness for Composites Part II: Precursor Damage Analysis and Quantification of Degraded Material Properties Using Quantitative Ultrasonic Image Correlation (QUIC)

PubMed Central

Patra, Subir; Banerjee, Sourav

2017-01-01

Material state awareness of composites using conventional Nondestructive Evaluation (NDE) method is limited by finding the size and the locations of the cracks and the delamination in a composite structure. To aid the progressive failure models using the slow growth criteria, the awareness of the precursor damage state and quantification of the degraded material properties is necessary, which is challenging using the current NDE methods. To quantify the material state, a new offline NDE method is reported herein. The new method named Quantitative Ultrasonic Image Correlation (QUIC) is devised, where the concept of microcontinuum mechanics is hybrid with the experimentally measured Ultrasonic wave parameters. This unique combination resulted in a parameter called Nonlocal Damage Entropy for the precursor awareness. High frequency (more than 25 MHz) scanning acoustic microscopy is employed for the proposed QUIC. Eight woven carbon-fiber-reinforced-plastic composite specimens were tested under fatigue up to 70% of their remaining useful life. During the first 30% of the life, the proposed nonlocal damage entropy is plotted to demonstrate the degradation of the material properties via awareness of the precursor damage state. Visual proofs for the precursor damage states are provided with the digital images obtained from the micro-optical microscopy, the scanning acoustic microscopy and the scanning electron microscopy. PMID:29258256

Understanding Greek Primary School Children's Comprehension of Sun Exposure.

ERIC Educational Resources Information Center

Piperakis, Stylianos M.; Papadimitriou, Vasiliki; Piperakis, Michael M.; Zisis, Panagiotis

2003-01-01

Assesses Greek primary school children's understanding of sun exposure during summer vacation. Results indicate that children know the damaging effects of long time exposure and the precautions that should be taken during summer bathing. (Author/SOE)

Hepatoprotective effects of Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] on alcohol-damaged primary rat hepatocyte culture in vitro.

PubMed

Jiang, Wenhua; Bian, Yuzhu; Wang, Zhenghui; Chang, Thomas Ming Swi

2017-02-01

We have prepared a novel nanobiotherapeutic, Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase], which not only transports both oxygen and carbon dioxide but also a therapeutic antioxidant. Our previous study in a severe sustained 90 min hemorrhagic shock rat model shows that it has a hepatoprotective effect. We investigate its hepatoprotective effect further in this present report using an alcohol-damaged primary hepatocyte culture model. Results show that it significantly reduced ethanol-induced AST release, lipid peroxidation, and ROS production in rat primary hepatocytes culture. It also significantly enhanced the viability of ethanol-treated hepatocytes. Thus, the result shows that Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] also has some hepatoprotective effects against alcohol-induced injury in in vitro rat primary hepatocytes cell culture. This collaborate our previous observation of its hepatoprotective effect in a severe sustained 90-min hemorrhagic shock rat model.

Modeling variability in air pollution-related health damages from individual airport emissions.

PubMed

Penn, Stefani L; Boone, Scott T; Harvey, Brian C; Heiger-Bernays, Wendy; Tripodis, Yorghos; Arunachalam, Sarav; Levy, Jonathan I

2017-07-01

In this study, we modeled concentrations of fine particulate matter (PM 2.5 ) and ozone (O 3 ) attributable to precursor emissions from individual airports in the United States, developing airport-specific health damage functions (deaths per 1000t of precursor emissions) and physically-interpretable regression models to explain variability in these functions. We applied the Community Multiscale Air Quality model using the Decoupled Direct Method to isolate PM 2.5 - or O 3 -related contributions from precursor pollutants emitted by 66 individual airports. We linked airport- and pollutant-specific concentrations with population data and literature-based concentration-response functions to create health damage functions. Deaths per 1000t of primary PM 2.5 emissions ranged from 3 to 160 across airports, with variability explained by population patterns within 500km of the airport. Deaths per 1000t of precursors for secondary PM 2.5 varied across airports from 0.1 to 2.7 for NOx, 0.06 to 2.9 for SO 2 , and 0.06 to 11 for VOCs, with variability explained by population patterns and ambient concentrations influencing particle formation. Deaths per 1000t of O 3 precursors ranged from -0.004 to 1.0 for NOx and 0.03 to 1.5 for VOCs, with strong seasonality and influence of ambient concentrations. Our findings reinforce the importance of location- and source-specific health damage functions in design of health-maximizing emissions control policies. Copyright © 2017 Elsevier Inc. All rights reserved.

Combination of Pim kinase inhibitor, SGI-1776, with bendamustine in B-cell lymphoma

PubMed Central

Yang, Qingshan; Chen, Lisa S; Neelapu, Sattva S.; Gandhi, Varsha

2013-01-01

SGI-1776 is a small molecule Pim kinase inhibitor that primarily targets c-Myc-driven transcription and cap-dependent translation in mantle cell lymphoma (MCL) cells. Bendamustine is an alkylating chemotherapeutic agent approved for use in B-cell lymphoma that is known to induce DNA damage and to initiate response to repair. We hypothesized that while each drug leads to the effects as stated above, combination of these drugs will enhance SGI-1776-induced inhibition of global transcription and translation processes, while promoting bendamustine-triggered decrease of DNA synthesis and DNA damage response in B-cell lymphoma. Both SGI-1776 and bendamustine as single agents effectively induced apoptosis and when used in combination, additive effect in cell killing was observed in MCL cell lines, JeKo-1 and Mino, as well as MCL and splenic marginal zone lymphoma (a type of B-cell lymphoma) primary cells. As expected, SGI-1776 was effective in inducing decrease of global RNA and protein synthesis, while bendamustine significantly inhibited DNA synthesis and generated DNA damage response. When used in combination, effects were intensified in DNA, RNA and protein syntheses compared to single agent treatments. Together, these data provided foundation and suggested feasibility of using Pim kinase inhibitor in combination with chemotherapeutic agents such as bendamustine in B-cell lymphoma. PMID:24290221

Research on FBG-Based CFRP Structural Damage Identification Using BP Neural Network

NASA Astrophysics Data System (ADS)

Geng, Xiangyi; Lu, Shizeng; Jiang, Mingshun; Sui, Qingmei; Lv, Shanshan; Xiao, Hang; Jia, Yuxi; Jia, Lei

2018-06-01

A damage identification system of carbon fiber reinforced plastics (CFRP) structures is investigated using fiber Bragg grating (FBG) sensors and back propagation (BP) neural network. FBG sensors are applied to construct the sensing network to detect the structural dynamic response signals generated by active actuation. The damage identification model is built based on the BP neural network. The dynamic signal characteristics extracted by the Fourier transform are the inputs, and the damage states are the outputs of the model. Besides, damages are simulated by placing lumped masses with different weights instead of inducing real damages, which is confirmed to be feasible by finite element analysis (FEA). At last, the damage identification system is verified on a CFRP plate with 300 mm × 300 mm experimental area, with the accurate identification of varied damage states. The system provides a practical way for CFRP structural damage identification.

Biological Activities of Reactive Oxygen and Nitrogen Species: Oxidative Stress versus Signal Transduction

PubMed Central

Weidinger, Adelheid; Kozlov, Andrey V.

2015-01-01

In the past, reactive oxygen and nitrogen species (RONS) were shown to cause oxidative damage to biomolecules, contributing to the development of a variety of diseases. However, recent evidence has suggested that intracellular RONS are an important component of intracellular signaling cascades. The aim of this review was to consolidate old and new ideas on the chemical, physiological and pathological role of RONS for a better understanding of their properties and specific activities. Critical consideration of the literature reveals that deleterious effects do not appear if only one primary species (superoxide radical, nitric oxide) is present in a biological system, even at high concentrations. The prerequisite of deleterious effects is the formation of highly reactive secondary species (hydroxyl radical, peroxynitrite), emerging exclusively upon reaction with another primary species or a transition metal. The secondary species are toxic, not well controlled, causing irreversible damage to all classes of biomolecules. In contrast, primary RONS are well controlled (superoxide dismutase, catalase), and their reactions with biomolecules are reversible, making them ideal for physiological/pathophysiological intracellular signaling. We assume that whether RONS have a signal transducing or damaging effect is primarily defined by their quality, being primary or secondary RONS, and only secondly by their quantity. PMID:25884116

49 CFR 198.35 - Grants conditioned on adoption of one-call damage prevention program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... considers whether a State has adopted or is seeking to adopt a one-call damage prevention program in accordance with § 198.37. If a State has not adopted or is not seeking to adopt such program, the State...

Space shuttle solid rocket booster main parachute damage reduction team report

NASA Technical Reports Server (NTRS)

Watts, G.

1993-01-01

This report gives the findings of the space shuttle solid rocket booster main parachute damage reduction team. The purpose of the team was to investigate the causes of main parachute deployment damage and to recommend methods to eliminate or substantially reduce the damage. The team concluded that the two primary causes of significant damage during deployment are vent entanglement and contact of the parachutes with the main parachute support structure. As an inexpensive but effective step towards damage reduction, the team recommends modification of the parachute packing procedure to eliminate vent entanglement. As the most effective design change, the team recommends a pilot chute-deployed soft-pack system. Alternative concepts are also recommended that provide a major reduction in damage at a total cost lower than the pilot chute-deployed soft pack.

Bonded repair of composite aircraft structures: A review of scientific challenges and opportunities

NASA Astrophysics Data System (ADS)

Katnam, K. B.; Da Silva, L. F. M.; Young, T. M.

2013-08-01

Advanced composite materials have gained popularity in high-performance structural designs such as aerospace applications that require lightweight components with superior mechanical properties in order to perform in demanding service conditions as well as provide energy efficiency. However, one of the major challenges that the aerospace industry faces with advanced composites - because of their inherent complex damage behaviour - is structural repair. Composite materials are primarily damaged by mechanical loads and/or environmental conditions. If material damage is not extensive, structural repair is the only feasible solution as replacing the entire component is not cost-effective in many cases. Bonded composite repairs (e.g. scarf patches) are generally preferred as they provide enhanced stress transfer mechanisms, joint efficiencies and aerodynamic performance. With an increased usage of advanced composites in primary and secondary aerospace structural components, it is thus essential to have robust, reliable and repeatable structural bonded repair procedures to restore damaged composite components. But structural bonded repairs, especially with primary structures, pose several scientific challenges with the current existing repair technologies. In this regard, the area of structural bonded repair of composites is broadly reviewed - starting from damage assessment to automation - to identify current scientific challenges and future opportunities.

The distribution of physicians workforce in Louisiana: results from a cross-sectional study.

PubMed

Masri, Maysoun Dimachkie; Oetjen, Reid; Campbell, Claudia; Webber, Larry; Diana, Mark L

2011-01-01

For the past two decades, Louisiana's population health rankings as reported by the United Health Foundation have been among the lowest in the nation. In addition, the 2009 Commonwealth State Scorecards Report ranked the Louisiana health system performance, in terms of health outcomes, among the poorest in the nation. One reason for this disparity could be attributed to shortages of physicians and other healthcare resources in the state. These shortages were exacerbated by the damage from Hurricanes Katrina and Rita in 2005 to hospitals and physicians' practices in New Orleans and throughout the state. This descriptive cross-sectional study focused on the geographical dimension of access and on one of its critical determinants: the availability of physicians. The objective behind this study was to offer a better understanding of the determinants of geographical imbalances in the distribution of physicians in the state of Louisiana. This study is part one of a three-part series that examines the association between total physician supply, primary care, and specialty care supply on mortality amenable to healthcare (MAHC).

Effects of stacking sequence on impact damage resistance and residual strength for quasi-isotropic laminates

NASA Technical Reports Server (NTRS)

Dost, Ernest F.; Ilcewicz, Larry B.; Avery, William B.; Coxon, Brian R.

1991-01-01

Residual strength of an impacted composite laminate is dependent on details of the damage state. Stacking sequence was varied to judge its effect on damage caused by low-velocity impact. This was done for quasi-isotropic layups of a toughened composite material. Experimental observations on changes in the impact damage state and postimpact compressive performance were presented for seven different laminate stacking sequences. The applicability and limitations of analysis compared to experimental results were also discussed. Postimpact compressive behavior was found to be a strong function of the laminate stacking sequence. This relationship was found to depend on thickness, stacking sequence, size, and location of sublaminates that comprise the impact damage state. The postimpact strength for specimens with a relatively symmetric distribution of damage through the laminate thickness was accurately predicted by models that accounted for sublaminate stability and in-plane stress redistribution. An asymmetric distribution of damage in some laminate stacking sequences tended to alter specimen stability. Geometrically nonlinear finite element analysis was used to predict this behavior.

OBJECT KINETIC MONTE CARLO SIMULATIONS OF RADIATION DAMAGE ACCUMULATION IN TUNGSTEN

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

Nandipati, Giridhar; Setyawan, Wahyu; Roche, Kenneth J.

2016-09-01

The objective of this work is to understand the accumulation of radiation damage created by primary knock-on atoms (PKAs) of various energies, at 300 K and for a dose rate of 10-4 dpa/s in bulk tungsten using the object kinetic Monte Carlo (OKMC) method.

Displacement Cascade Damage Production in Metals

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

Stoller, Roger E; Malerba, Lorenzo; Nordlund, Kai

Radiation-induced changes in microstructure and mechanical properties in structural materials are the result of a complex set of physical processes initiated by the collision between an energetic particle (neutron or ion) and an atom in the lattice. This primary damage event is called an atomic displacement cascade. The simplest description of a displacement cascade is to view it as a series of many billiard-ball-like elastic collisions among the atoms in the material. This chapter describes the formation and evolution of this primary radiation damage mechanism to provide an overview of how stable defects are formed by displacement cascades, as wellmore » as the nature and morphology of the defects themselves. The impact of the relevant variables such as cascade energy and irradiation temperature is discussed, and defect formation in different materials is compared.« less

36 CFR 228.110 - Indemnification.

Code of Federal Regulations, 2010 CFR

2010-07-01

... United States for: (a) Injury, loss or damage, including fire suppression costs, which the United States incurs as a result of the operations; and (b) Payments made by the United States in satisfaction of claims, demands or judgments for an injury, loss or damage, including fire suppression costs, which...

Taxation of mineral resources

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

Conrad, R.F.; Hool, R.B.

1980-01-01

There has been a substantial increase in recent years in the level of taxation imposed on mining firms by state and local governments. This increase can be attributed to three factors: (1) a heightened awareness that resources are limited in quantity; (2) environmental damage resulting from mining operations has brought demands for just compensations; and (3) significant price increases for some minerals have often been viewed by states as an opportunity to collect additional tax revenue. The broad aim of this book is to provide a comprehensive economic analysis of the effects of mining taxation on the extraction of mineralmore » resources and to offer a set of recommendations for tax policy. The primary objective of this design is to minimize the distortionary incentives created by the taxation. From a practical standpoint, however, one must also recognize the degrees of difficulty in the administration of the various taxes. 90 references, 1 figure, 14 tables.« less

Effects of a Mangifera indica L. stem bark extract and mangiferin on radiation-induced DNA damage in human lymphocytes and lymphoblastoid cells.

PubMed

Rodeiro, I; Delgado, R; Garrido, G

2014-02-01

Mangifera indica L. (mango) stem bark aqueous extract (MSBE) that has antioxidant, anti-inflammatory and immunomodulatory properties, can be obtained in Cuba. It is rich in polyphenols, where mangiferin is the main component. In this study, we have tested DNA damage and protection effects of MSBE and mangiferin on primary human lymphocytes and lymphoblastoid cells. Cell suspensions were incubated with the products (50-1000 μg/ml) for experiments on damage induction, and evaluation of any potential protective effects (5-100 μg/ml) for 60 min at 37 °C. Irradiation was performed using a γ-ray source, absorbed dose 5 Gy. At the end of exposure, DNA damage, protection and repair processes were evaluated using the comet assay. MSBE (100-1000 μg/ml) induced DNA damage in a concentration dependent manner in both cell types tested, primary cells being more sensitive. Mangiferin (200 μg/ml) only induced light DNA damage at higher concentrations. DNA repair capacity was not affected after MSBE or mangiferin exposure. On the other hand, MSBE (25 and 50 μg/ml) and mangiferin (5-25 ug/ml) protected against gamma radiation-induced DNA damage. These results show MSBE has protector or harmful effects on DNA in vitro depending on the experimental conditions, which suggest that the extract could be acting as an antioxidant or pro-oxidant product. Mangiferin was involved in protective effects of the extract. © 2013 John Wiley & Sons Ltd.

A Bayesian state-space approach for damage detection and classification

NASA Astrophysics Data System (ADS)

Dzunic, Zoran; Chen, Justin G.; Mobahi, Hossein; Büyüköztürk, Oral; Fisher, John W.

2017-11-01

The problem of automatic damage detection in civil structures is complex and requires a system that can interpret collected sensor data into meaningful information. We apply our recently developed switching Bayesian model for dependency analysis to the problems of damage detection and classification. The model relies on a state-space approach that accounts for noisy measurement processes and missing data, which also infers the statistical temporal dependency between measurement locations signifying the potential flow of information within the structure. A Gibbs sampling algorithm is used to simultaneously infer the latent states, parameters of the state dynamics, the dependence graph, and any changes in behavior. By employing a fully Bayesian approach, we are able to characterize uncertainty in these variables via their posterior distribution and provide probabilistic estimates of the occurrence of damage or a specific damage scenario. We also implement a single class classification method which is more realistic for most real world situations where training data for a damaged structure is not available. We demonstrate the methodology with experimental test data from a laboratory model structure and accelerometer data from a real world structure during different environmental and excitation conditions.

Damage states in laminated composite three-point bend specimens: An experimental-analytical correlation study

NASA Technical Reports Server (NTRS)

Starbuck, J. Michael; Guerdal, Zafer; Pindera, Marek-Jerzy; Poe, Clarence C.

1990-01-01

Damage states in laminated composites were studied by considering the model problem of a laminated beam subjected to three-point bending. A combination of experimental and theoretical research techniques was used to correlate the experimental results with the analytical stress distributions. The analytical solution procedure was based on the stress formulation approach of the mathematical theory of elasticity. The solution procedure is capable of calculating the ply-level stresses and beam displacements for any laminated beam of finite length using the generalized plane deformation or plane stress state assumption. Prior to conducting the experimental phase, the results from preliminary analyses were examined. Significant effects in the ply-level stress distributions were seen depending on the fiber orientation, aspect ratio, and whether or not a grouped or interspersed stacking sequence was used. The experimental investigation was conducted to determine the different damage modes in laminated three-point bend specimens. The test matrix consisted of three-point bend specimens of 0 deg unidirectional, cross-ply, and quasi-isotropic stacking sequences. The dependence of the damage initiation loads and ultimate failure loads were studied, and their relation to damage susceptibility and damage tolerance of the mean configuration was discussed. Damage modes were identified by visual inspection of the damaged specimens using an optical microscope. The four fundamental damage mechanisms identified were delaminations, matrix cracking, fiber breakage, and crushing. The correlation study between the experimental results and the analytical results were performed for the midspan deflection, indentation, damage modes, and damage susceptibility.

Internal state variable plasticity-damage modeling of AISI 4140 steel including microstructure-property relations: temperature and strain rate effects

NASA Astrophysics Data System (ADS)

Nacif el Alaoui, Reda

Mechanical structure-property relations have been quantified for AISI 4140 steel. under different strain rates and temperatures. The structure-property relations were used. to calibrate a microstructure-based internal state variable plasticity-damage model for. monotonic tension, compression and torsion plasticity, as well as damage evolution. Strong stress state and temperature dependences were observed for the AISI 4140 steel. Tension tests on three different notched Bridgman specimens were undertaken to study. the damage-triaxiality dependence for model validation purposes. Fracture surface. analysis was performed using Scanning Electron Microscopy (SEM) to quantify the void. nucleation and void sizes in the different specimens. The stress-strain behavior exhibited. a fairly large applied stress state (tension, compression dependence, and torsion), a. moderate temperature dependence, and a relatively small strain rate dependence.

OBJECT KINETIC MONTE CARLO SIMULATIONS OF CASCADE ANNEALING IN TUNGSTEN

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

Nandipati, Giridhar; Setyawan, Wahyu; Heinisch, Howard L.

2014-03-31

The objective of this work is to study the annealing of primary cascade damage created by primary knock-on atoms (PKAs) of various energies, at various temperatures in bulk tungsten using the object kinetic Monte Carlo (OKMC) method.

Strategies for immortalization of primary hepatocytes

PubMed Central

Eva, Ramboer; Bram, De Craene; Joery, De Kock; Tamara, Vanhaecke; Geert, Berx; Vera, Rogiers; Mathieu, Vinken

2014-01-01

The liver has the unique capacity to regenerate in response to a damaging event. Liver regeneration is hereby largely driven by hepatocyte proliferation, which in turn relies on cell cycling. The hepatocyte cell cycle is a complex process that is tightly regulated by several well-established mechanisms. In vitro, isolated hepatocytes do not longer retain this proliferative capacity. However, in vitro cell growth can be boosted by immortalization of hepatocytes. Well-defined immortalization genes can be artificially overexpressed in hepatocytes or the cells can be conditionally immortalized leading to controlled cell proliferation. This paper discusses the current immortalization techniques and provides a state-of-the-art overview of the actually available immortalized hepatocyte-derived cell lines and their applications. PMID:24911463

The Impact of State Tort Reforms on Imaging Utilization.

PubMed

Li, Suhui; Dor, Avi; Deyo, Darwyyn; Hughes, Danny R

2017-02-01

Defensive medicine, broadly defined as medical practices that protect physicians from malpractice lawsuits without providing benefits to patients, can lead to wasteful use of health care resources and higher cost. Although physicians cite malpractice liability as an important factor driving their decisions to order imaging tests, little research has been done to examine the systematic impact of liability pressure on overall imaging. The authors examined the extent to which radiography use is influenced by malpractice liability pressure among office-based physicians. Using National Ambulatory Medical Care Survey data from 1999 to 2010, the authors used multivariate difference-in-difference logistic regression to examine the effects of different types of state tort reforms on the probability of radiography orders by primary care physicians (PCPs) and specialists. The probability that a PCP ordered radiography decreased when states enacted permanent caps on noneconomic damages (-1.0%, P < .01), periodic payment reforms (-1.6%, P < .05), and the total number of tort reforms (-0.5%, P < .05). Specialist physicians were responsive to two reforms: caps on punitive damages (-6.1%, P < .01) and the total number of medical tort laws (-1.2%, P < .01). The passage of new indirect reforms was found to reduce radiography orders for PCPs (-1.8%, P < .05), and the repeal of indirect reforms was found to increase radiography orders for specialists (+3.4%, P < .01). State tort reform seems to reduce physicians' ordering of radiography. This analysis also suggests that reforms that make it harder to sue physicians have a stronger impact than reforms that directly reduce physicians' malpractice claim payments. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Fatigue Damage in Notched Composite Laminates Under Tension-Tension Cyclic Loads

NASA Technical Reports Server (NTRS)

Stinchcomb, W. W.; Henneke, E. G.; Reifsnider, K. L.; Kress, G. R.

1985-01-01

The results are given of an investigation to determine the damage states which develop in graphite epoxy laminates with center holes due to tension-tension cyclic loads, to determine the influence of stacking sequence on the initiation and interaction of damage modes and the process of damage development, and to establish the relationships between the damage states and the strength, stiffness, and life of the laminates. Two quasi-isotropic laminates were selected to give different distributions of interlaminar stresses around the hole. The laminates were tested under cyclic loads (R=0.1, 10 Hz) at maximum stresses ranging between 60 and 95 percent of the notched tensile strength.

Repair of Bonded Primary Structure

DTIC Science & Technology

1978-06-01

of the body 2. Operational Items a. lard Landings * Damage to the wheel well area and in proximity of’ the lanuing gear beams b. Foreign Object...their main problems with the C-1 30 are to the ramp hinge support bulkhead and landing gear wheel well area. Lockheed has repair kits for each of these...MAC). The wheel well area is quite .ttsceptible to damage from hard landings. E’xcess runway water causes damage to the wheel well doors. Other

Inactivation of NADPH oxidases NOX4 and NOX5 protects human primary fibroblasts from ionizing radiation-induced DNA damage.

PubMed

Weyemi, Urbain; Redon, Christophe E; Aziz, Towqir; Choudhuri, Rohini; Maeda, Daisuke; Parekh, Palak R; Bonner, Michael Y; Arbiser, Jack L; Bonner, William M

2015-03-01

Human exposure to ionizing radiation from medical procedures has increased sharply in the last three decades. Recent epidemiological studies suggest a direct relationship between exposure to ionizing radiation and health problems, including cancer incidence. Therefore, minimizing the impact of radiation exposure in patients has become a priority in the development of future clinical practices. Crucial players in radiation-induced DNA damage include reactive oxygen species (ROS), but the sources of these have remained elusive. To the best of our knowledge, we show here for the first time that two members of the ROS-generating NADPH oxidase family (NOXs), NOX4 and NOX5, are involved in radiation-induced DNA damage. Depleting these two NOXs in human primary fibroblasts resulted in reduced levels of DNA damage as measured by levels of radiation-induced foci, a marker of DNA double-strand breaks (DSBs) and the comet assay coupled with increased cell survival. NOX involvement was substantiated with fulvene-5, a NOXs-specific inhibitor. Moreover, fulvene-5 mitigated radiation-induced DNA damage in human peripheral blood mononuclear cells ex vivo. Our results provide evidence that the inactivation of NOXs protects cells from radiation-induced DNA damage and cell death. These findings suggest that NOXs inhibition may be considered as a future pharmacological target to help minimize the negative effects of radiation exposure for millions of patients each year.

Inactivation of NADPH Oxidases NOX4 and NOX5 Protects Human Primary Fibroblasts from Ionizing Radiation-Induced DNA Damage

PubMed Central

Weyemi, Urbain; Redon, Christophe E.; Aziz, Towqir; Choudhuri, Rohini; Maeda, Daisuke; Parekh, Palak R.; Bonner, Michael Y.; Arbiser, Jack L.; Bonner, William M.

2015-01-01

Human exposure to ionizing radiation from medical procedures has increased sharply in the last three decades. Recent epidemiological studies suggest a direct relationship between exposure to ionizing radiation and health problems, including cancer incidence. Therefore, minimizing the impact of radiation exposure in patients has become a priority in the development of future clinical practices. Crucial players in radiation-induced DNA damage include reactive oxygen species (ROS), but the sources of these have remained elusive. To the best of our knowledge, we show here for the first time that two members of the ROS-generating NADPH oxidase family (NOXs), NOX4 and NOX5, are involved in radiation-induced DNA damage. Depleting these two NOXs in human primary fibroblasts resulted in reduced levels of DNA damage as measured by levels of radiation-induced foci, a marker of DNA double-strand breaks (DSBs) and the comet assay coupled with increased cell survival. NOX involvement was substantiated with fulvene-5, a NOXs-specific inhibitor. Moreover, fulvene-5 mitigated radiation-induced DNA damage in human peripheral blood mononuclear cells ex vivo. Our results provide evidence that the inactivation of NOXs protects cells from radiation-induced DNA damage and cell death. These findings suggest that NOXs inhibition may be considered as a future pharmacological target to help minimize the negative effects of radiation exposure for millions of patients each year. PMID:25706776

Inhibition of SIRT1 Catalytic Activity Increases p53 Acetylation but Does Not Alter Cell Survival following DNA Damage

PubMed Central

Solomon, Jonathan M.; Pasupuleti, Rao; Xu, Lei; McDonagh, Thomas; Curtis, Rory; DiStefano, Peter S.; Huber, L. Julie

2006-01-01

Human SIRT1 is an enzyme that deacetylates the p53 tumor suppressor protein and has been suggested to modulate p53-dependent functions including DNA damage-induced cell death. In this report, we used EX-527, a novel, potent, and specific small-molecule inhibitor of SIRT1 catalytic activity to examine the role of SIRT1 in p53 acetylation and cell survival after DNA damage. Treatment with EX-527 dramatically increased acetylation at lysine 382 of p53 after different types of DNA damage in primary human mammary epithelial cells and several cell lines. Significantly, inhibition of SIRT1 catalytic activity by EX-527 had no effect on cell growth, viability, or p53-controlled gene expression in cells treated with etoposide. Acetyl-p53 was also increased by the histone deacetylase (HDAC) class I/II inhibitor trichostatin A (TSA). EX-527 and TSA acted synergistically to increase acetyl-p53 levels, confirming that p53 acetylation is regulated by both SIRT1 and HDACs. While TSA alone reduced cell survival after DNA damage, the combination of EX-527 and TSA had no further effect on cell viability and growth. These results show that, although SIRT1 deacetylates p53, this does not play a role in cell survival following DNA damage in certain cell lines and primary human mammary epithelial cells. PMID:16354677

Pathophysiology of primary open-angle glaucoma from a neuroinflammatory and neurotoxicity perspective: a review of the literature.

PubMed

Evangelho, Karine; Mogilevskaya, Maria; Losada-Barragan, Monica; Vargas-Sanchez, Jeinny Karina

2017-12-30

Glaucoma is the leading cause of blindness in humans, affecting 2% of the population. This disorder can be classified into various types including primary, secondary, glaucoma with angle closure and with open angle. The prevalence of distinct types of glaucoma differs for each particular region of the world. One of the most common types of this disease is primary open-angle glaucoma (POAG), which is a complex inherited disorder characterized by progressive retinal ganglion cell death, optic nerve head excavation and visual field loss. Nowadays, POAG is considered an optic neuropathy, while intraocular pressure is proposed to play a fundamental role in its pathophysiology and especially in optic disk damage. However, the exact mechanism of optic nerve head damage remains a topic of debate. This literature review aims to bring together the information on the pathophysiology of primary open-angle glaucoma, particularly focusing on neuroinflammatory mechanisms leading to the death of the retinal ganglion cell. A literature search was done on PubMed using key words including primary open-angle glaucoma, retinal ganglion cells, Müller cells, glutamate, glial cells, ischemia, hypoxia, exitotoxicity, neuroinflammation, axotomy and neurotrophic factors. The literature was reviewed to collect the information published about the pathophysiologic mechanisms of RGC death in the POAG, from a neuroinflammatory and neurotoxicity perspective. Proposed mechanisms for glaucomatous damage are a result of pressure in RGC followed by ischemia, hypoxia of the ONH, and consequently death due to glutamate-induced excitotoxicity, deprivation of energy and oxygen, increase in levels of inflammatory mediators and alteration of trophic factors flow. These events lead to blockage of anterograde and retrograde axonal transport with ensuing axotomy and eventually blindness. The damage to ganglion cells and eventually glaucomatous injury can occur via various mechanisms including baric trauma, ischemia and impact of metabolic toxins, which triggers an inflammatory process and secondary degeneration in the ONH.

A Simplified Algorithm for Statistical Investigation of Damage Spreading

NASA Astrophysics Data System (ADS)

Gecow, Andrzej

2009-04-01

On the way to simulating adaptive evolution of complex system describing a living object or human developed project, a fitness should be defined on node states or network external outputs. Feedbacks lead to circular attractors of these states or outputs which make it difficult to define a fitness. The main statistical effects of adaptive condition are the result of small change tendency and to appear, they only need a statistically correct size of damage initiated by evolutionary change of system. This observation allows to cut loops of feedbacks and in effect to obtain a particular statistically correct state instead of a long circular attractor which in the quenched model is expected for chaotic network with feedback. Defining fitness on such states is simple. We calculate only damaged nodes and only once. Such an algorithm is optimal for investigation of damage spreading i.e. statistical connections of structural parameters of initial change with the size of effected damage. It is a reversed-annealed method—function and states (signals) may be randomly substituted but connections are important and are preserved. The small damages important for adaptive evolution are correctly depicted in comparison to Derrida annealed approximation which expects equilibrium levels for large networks. The algorithm indicates these levels correctly. The relevant program in Pascal, which executes the algorithm for a wide range of parameters, can be obtained from the author.

Emergence of white pine needle damage in the northeastern United States is associated with changes in pathogen pressure in response to climate change.

PubMed

Wyka, Stephen A; Smith, Cheryl; Munck, Isabel A; Rock, Barrett N; Ziniti, Beth L; Broders, Kirk

2017-01-01

The defoliation of the eastern white pine (Pinus strobus) across the northeastern United States is an escalating concern threatening the ecological health of northern forests and economic vitality of the region's lumber industry. First documented in the spring of 2010 affecting 24 328 hectares in the state of Maine, white pine needle damage (WPND) has continued to spread and is now well established in all New England states. While causal agents of WPND are known, current research is lacking in both sampling distribution and the specific environmental factor(s) that affect the development and spread of this disease complex. This study aims to construct a more detailed distribution map of the four primary causal agents within the region, as well as utilize long-term WPND monitoring plots and data collected from land-based weather stations to develop a climatic model to predict the severity of defoliation events in the proceeding year. Sampling results showed a greater distribution of WPND than previously reported. WPND was generally found in forest stands that compromised >50% eastern white pine by basal area. No single species, nor a specific combination of species had a dominating presence in particular states or regions, thus supporting the disease complex theory that WPND is neither caused by an individual species nor by a specific combination of species. In addition, regional weather data confirmed the trend of increasing temperature and precipitation observed in this region with the previous year's May, June, and July rainfall being the best predictor of defoliation events in the following year. Climatic models were developed to aid land managers in predicting disease severity and accordingly adjust their management decisions. Our results clearly demonstrate the role changing climate patterns have on the health of eastern white pine in the northeastern United States. © 2016 John Wiley & Sons Ltd.

Modeling damaged wings: Element selection and constraint specification

NASA Technical Reports Server (NTRS)

Stronge, W. J.

1975-01-01

The NASTRAN analytical program was used for structural design, and no problems were anticipated in applying this program to a damaged structure as long as the deformations were small and the strains remained within the elastic range. In this context, NASTRAN was used to test three-dimensional analytical models of a damaged aircraft wing under static loads. A comparison was made of calculated and experimentally measured strains on primary structural components of an RF-84F wing. This comparison brought out two sensitive areas in modeling semimonocoque structures. The calculated strains were strongly affected by the type of elements used adjacent to the damaged region and by the choice of multipoint constraints sets on the damaged boundary.

20 CFR 10.712 - How much of any settlement or judgment must be paid to the United States?

Code of Federal Regulations, 2014 CFR

2014-04-01

... entire amount of the award; (ii) Subtract the amount of award representing damage to real or personal... Damage $0.00 (iii) Subtotal A (Line a minus Line b) $100,000.00 (iv) Amount Allocated for Loss of... which is permitted under the state law and for damage to her vehicle (documented at $50,000.00). A joint...

20 CFR 10.712 - How much of any settlement or judgment must be paid to the United States?

Code of Federal Regulations, 2013 CFR

2013-04-01

... entire amount of the award; (ii) Subtract the amount of award representing damage to real or personal... Damage $0.00 (iii) Subtotal A (Line a minus Line b) $100,000.00 (iv) Amount Allocated for Loss of... which is permitted under the state law and for damage to her vehicle (documented at $50,000.00). A joint...

20 CFR 10.712 - How much of any settlement or judgment must be paid to the United States?

Code of Federal Regulations, 2012 CFR

2012-04-01

... entire amount of the award; (ii) Subtract the amount of award representing damage to real or personal... Damage $0.00 (iii) Subtotal A (Line a minus Line b) $100,000.00 (iv) Amount Allocated for Loss of... which is permitted under the state law and for damage to her vehicle (documented at $50,000.00). A joint...

Mapping the occurrence of tree damage in the forests of the northern United States

Treesearch

Randall S. Morin; Scott A. Pugh; Jim. Steinman

2016-01-01

The U.S. Forest Service Forest Inventory and Analysis Program uses visual inspections of trees from bottom to top to record damage that is likely to prevent survival, reduce growth, or hinder capability to produce marketable products. This report describes the types of damage and occurrence as measured across the 24-state northern region between 2009 and 2013....

Relationship Between Malpractice Litigation Pressure and Rates of Cesarean Section and Vaginal Birth After Cesarean Section

PubMed Central

Yang, Y. Tony; Mello, Michelle M.; Subramanian, S. V.; Studdert, David M.

2011-01-01

Background Since the 1990s, nationwide rates of vaginal birth after cesarean section (VBAC) have decreased sharply and rates of cesarean section have increased sharply. Both trends are consistent with clinical behavior aimed at reducing obstetricians’ exposure to malpractice litigation. Objective To estimate the effects of malpractice pressure on rates of VBAC and cesarean section. Research Design, Subjects, Measures We used state-level longitudinal mixed-effects regression models to examine data from the Natality Detail File on births in the United States (1991–2003). Malpractice pressure was measured by liability insurance premiums and tort reforms. Outcome measures were rates of VBAC, cesarean section, and primary cesarean section. Results Malpractice premiums were positively associated with rates of cesarean section (β = 0.15, P = 0.02) and primary cesarean section (β = 0.16, P = 0.009), and negatively associated with VBAC rates (β = −0.35, P = 0.01). These estimates imply that a $10,000 decrease in premiums for obstetrician-gynecologists would be associated with an increase of 0.35 percentage points (1.45%) in the VBAC rate and decreases of 0.15 and 0.16 percentage points (0.7% and 1.18%) in the rates of cesarean section and primary cesarean section, respectively; this would correspond to approximately 1600 more VBACs, 6000 fewer cesarean sections, and 3600 fewer primary cesarean sections nationwide in 2003. Two types of tort reform—caps on noneconomic damages and pretrial screening panels—were associated with lower rates of cesarean section and higher rates of VBAC. Conclusions The liability environment influences choice of delivery method in obstetrics. The effects are not large, but reduced litigation pressure would likely lead to decreases in the total number cesarean sections and total delivery costs. PMID:19169125

Relationship between malpractice litigation pressure and rates of cesarean section and vaginal birth after cesarean section.

PubMed

Yang, Y Tony; Mello, Michelle M; Subramanian, S V; Studdert, David M

2009-02-01

Since the 1990s, nationwide rates of vaginal birth after cesarean section (VBAC) have decreased sharply and rates of cesarean section have increased sharply. Both trends are consistent with clinical behavior aimed at reducing obstetricians' exposure to malpractice litigation. To estimate the effects of malpractice pressure on rates of VBAC and cesarean section. We used state-level longitudinal mixed-effects regression models to examine data from the Natality Detail File on births in the United States (1991-2003). Malpractice pressure was measured by liability insurance premiums and tort reforms. Outcome measures were rates of VBAC, cesarean section, and primary cesarean section. Malpractice premiums were positively associated with rates of cesarean section (beta = 0.15, P = 0.02) and primary cesarean section (beta = 0.16, P = 0.009), and negatively associated with VBAC rates (beta = -0.35, P = 0.01). These estimates imply that a $10,000 decrease in premiums for obstetrician-gynecologists would be associated with an increase of 0.35 percentage points (1.45%) in the VBAC rate and decreases of 0.15 and 0.16 percentage points (0.7% and 1.18%) in the rates of cesarean section and primary cesarean section, respectively; this would correspond to approximately 1600 more VBACs, 6000 fewer cesarean sections, and 3600 fewer primary cesarean sections nationwide in 2003. Two types of tort reform-caps on noneconomic damages and pretrial screening panels-were associated with lower rates of cesarean section and higher rates of VBAC. The liability environment influences choice of delivery method in obstetrics. The effects are not large, but reduced litigation pressure would likely lead to decreases in the total number cesarean sections and total delivery costs.

Theory of ultrasonic diffraction by damage developed in thin laminated composites

NASA Technical Reports Server (NTRS)

Hayford, D. T.; Henneke, E. G.

1977-01-01

The apparent attenuation which would result if certain damage states (transverse cracks and delaminations) are introduced into a graphite/epoxy laminate through which an ultrasonic wave passes is investigated. Experimental data for two different laminates are presented which shows changes in the apparent attenuation of about one db. These changes generally occur at loads which correspond to the range predicted for the formation of the damage. The predicted changes in the attenuation for several simple and common damage states are well within the range of experimental values.

A viscoelastic damage rheology and rate- and state-dependent friction

NASA Astrophysics Data System (ADS)

Lyakhovsky, Vladimir; Ben-Zion, Yehuda; Agnon, Amotz

2005-04-01

We analyse the relations between a viscoelastic damage rheology model and rate- and state-dependent (RS) friction. Both frameworks describe brittle deformation, although the former models localization zones in a deforming volume while the latter is associated with sliding on existing surfaces. The viscoelastic damage model accounts for evolving elastic properties and inelastic strain. The evolving elastic properties are related quantitatively to a damage state variable representing the local density of microcracks. Positive and negative changes of the damage variable lead, respectively, to degradation and recovery of the material in response to loading. A model configuration having an existing narrow zone with localized damage produces for appropriate loading and temperature-pressure conditions an overall cyclic stick-slip motion compatible with a frictional response. Each deformation cycle (limit cycle) can be divided into healing and weakening periods associated with decreasing and increasing damage, respectively. The direct effect of the RS friction and the magnitude of the frictional parameter a are related to material strengthening with increasing rate of loading. The strength and residence time of asperities (model elements) in the weakening stage depend on the rates of damage evolution and accumulation of irreversible strain. The evolutionary effect of the RS friction and overall change in the friction parameters (a-b) are controlled by the duration of the healing period and asperity (element) strengthening during this stage. For a model with spatially variable properties, the damage rheology reproduces the logarithmic dependency of the steady-state friction coefficient on the sliding velocity and the normal stress. The transition from a velocity strengthening regime to a velocity weakening one can be obtained by varying the rate of inelastic strain accumulation and keeping the other damage rheology parameters fixed. The developments unify previous damage rheology results on deformation localization leading to formation of new fault zones with detailed experimental results on frictional sliding. The results provide a route for extending the formulation of RS friction into a non-linear continuum mechanics framework.

ENHANCED BINDING OF AUTOLOGOUS RED CELLS TO THE MACROPHAGE PLASMA MEMBRANE AS A SENSITIVE INDICATOR OF POLLUTANT DAMAGE

EPA Science Inventory

The alveolar macrophage (AM) represents the primary line of defense in host protection against inhaled infectious organisms. Following exposure to oxidant gases, the ability of the host to resist airborne bacterial infection is severely impaired, and damage to the AM defense syst...

Identification of substrates for transglutaminase in Physarum polycephalum, an acellular slime mold, upon cellular mechanical damage.

PubMed

Wada, Fumitaka; Hasegawa, Hiroki; Nakamura, Akio; Sugimura, Yoshiaki; Kawai, Yoshiki; Sasaki, Narie; Shibata, Hideki; Maki, Masatoshi; Hitomi, Kiyotaka

2007-06-01

Transglutaminases are Ca(2+)-dependent enzymes that post-translationally modify proteins by crosslinking or polyamination at specific polypeptide-bound glutamine residues. Physarum polycephalum, an acellular slime mold, is the evolutionarily lowest organism expressing a transglutimase whose primary structure is similar to that of mammalian transglutimases. We observed transglutimase reaction products at injured sites in Physarum macroplasmodia upon mechanical damage. With use of a biotin-labeled primary amine, three major proteins constituting possible transglutimase substrates were affinity-purified from the damaged slime mold. The purified proteins were Physarum actin, a 40 kDa Ca(2+)-binding protein with four EF-hand motifs (CBP40), and a novel 33 kDa protein highly homologous to the eukaryotic adenine nucleotide translocator, which is expressed in mitochondria. Immunochemical analysis of extracts from the damaged macroplasmodia indicated that CBP40 is partly dimerized, whereas the other proteins migrated as monomers on SDS/PAGE. Of the three proteins, CBP40 accumulated most significantly around injured areas, as observed by immunofluoresence. These results suggested that transglutimase reactions function in the response to mechanical injury.

Modified stoke ankylosing spondylitis spinal score as an outcome measure to assess the impact of treatment on structural progression in ankylosing spondylitis.

PubMed

van der Heijde, Désirée; Braun, Jürgen; Deodhar, Atul; Baraliakos, Xenofon; Landewé, Robert; Richards, Hanno B; Porter, Brian; Readie, Aimee

2018-05-30

In ankylosing spondylitis (AS), structural damage that occurs as a result of syndesmophyte formation and ankylosis of the vertebral column is irreversible. Structural damage is currently assessed by conventional radiography and scoring systems that reliably assess radiographic structural damage are needed to capture the differential effects of drugs on structural damage progression. The validity of the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) as a primary outcome measure in evaluating the effect of AS treatments on radiographic progression rates was assessed in this review. The mSASSS has not been used, to date, as a primary outcome measure in a prospective randomized controlled clinical trial of biologic therapy in AS. This review of the medical literature confirmed that the mSASSS is the most validated and widely used method for assessing radiographic progression in AS, correlating with worsening measures of disease signs and symptoms, spinal mobility and physical function, with a 2-year interval being required to ensure sufficient sensitivity to change.

[The legal issue of the present occupational physician system in crisis management of health damage].

PubMed

Yuki, Tomoshi; Hakozaki, Yukiya; Yoshinaga, Takeo; Koizumi, Akio

2004-09-01

In present day Japan, when a crisis like the Bhopal accident occurs, due to defects in the current of industrial health law, effective crisis management cannot be taken to minimize health damage in both workers and residents. The current law characterizes industrial health as a part of the welfare service provided by employers for employees. Nevertheless, the company should be liable for all failure and damage including health impairment as a primary party. Moreover, in an emergency crisis, unlike the case of reparations, it is not accepted to argue whether the company should take absolute liability or not. Accordingly, in such cases, we consider it more appropriate to apply the "Polluter Pays Principle" and the principle of "Liability without Fault" to the company's responsibility. By these rules, the company should mobilize their own professionals, who are experts of managing crises, such as occupational physicians and/or industrial health professionals to minimize health damages among citizens in general. The company should take such a social responsibility in a crisis when it is the primary responsible party to the crisis.

Understanding the drivers of extensive plant damage in boreal and Arctic ecosystems: Insights from field surveys in the aftermath of damage.

PubMed

Bjerke, Jarle W; Treharne, Rachael; Vikhamar-Schuler, Dagrun; Karlsen, Stein R; Ravolainen, Virve; Bokhorst, Stef; Phoenix, Gareth K; Bochenek, Zbigniew; Tømmervik, Hans

2017-12-01

The exact cause of population dieback in nature is often challenging to identify retrospectively. Plant research in northern regions has in recent decades been largely focussed on the opposite trend, namely increasing populations and higher productivity. However, a recent unexpected decline in remotely-sensed estimates of terrestrial Arctic primary productivity suggests that warmer northern lands do not necessarily result in higher productivity. As large-scale plant dieback may become more frequent at high northern latitudes with increasing frequency of extreme events, understanding the drivers of plant dieback is especially urgent. Here, we report on recent extensive damage to dominant, short, perennial heath and tundra plant populations in boreal and Arctic Norway, and assess the potential drivers of this damage. In the High-Arctic archipelago of Svalbard, we recorded that 8-50% of Cassiope tetragona and Dryas octopetala shoots were dead, and that the ratios of dead shoots increased from 2014 to 2015. In boreal Norway, 38-63% of Calluna vulgaris shoots were dead, while Vaccinium myrtillus had damage to 91% of shoots in forested sites, but was healthy in non-forested sites. Analyses of numerous sources of environmental information clearly point towards a winter climate-related reason for damage to three of these four species. In Svalbard, the winters of 2011/12 and 2014/15 were documented to be unusually severe, i.e. insulation from ambient temperature fluctuation by snow was largely absent, and ground-ice enforced additional stress. In boreal Norway, the 2013/14 winter had a long period with very little snow combined with extremely low precipitation rates, something which resulted in frost drought of uncovered Calluna plants. However, extensive outbreaks of a leaf-defoliating geometrid moth were identified as the driver of Vaccinium mortality. These results suggest that weather and biotic extreme events potentially have strong impacts on the vegetation state of northern lands. Copyright © 2017 Elsevier B.V. All rights reserved.

The control of iron-induced oxidative damage in isolated rat-liver mitochondria by respiration state and ascorbate.

PubMed

Burkitt, M J; Gilbert, B C

1989-01-01

The reaction of iron (II) with H2O2 is believed to generate highly reactive species (e.g. .OH) capable of initiating biological damage. This study investigates the possibility that the severity of oxidative damage induced by iron in hepatic mitochondria is determined by the level of mitochondrial-H2O2 generation, which is believed to be particularly prominent in state-4 respiration. Iron-induced damage is found to be greater in state-4 than in state-3 respiration. Experiments using uncoupling agents and Ca++ to mimic state-3 conditions indicate that this effect reflects differences in the steady-state oxidation-level of the electron carriers of the respiratory chain (and hence the level of H2O2-generation), rather than changes in redox potential or transportation of the metal-ion. Evidence is also presented for a mechanism in which Fe(II) and H2O2 react inside the mitochondrial matrix. Ascorbate (vitamin C) is shown to be pro-oxidant in this system, except when present at very high concentration when it becomes antioxidant in nature.

Earthquakes, July-August, 1979

USGS Publications Warehouse

Person, W.J.

1980-01-01

In the United States, on August 6, central California experienced a moderately strong earthquake, which injured several people and caused some damage. A number of earthquakes occurred in other parts of the United States but caused very little damage. 

Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

PubMed Central

Zuluaga-Ramírez, Pablo; Frövel, Malte; Belenguer, Tomás; Salazar, Félix

2015-01-01

This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL) and realistic variable amplitude loads (VAL), representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications. PMID:28793655

[Neuropsychological subtypes of the inattention and hyperactivity syndrome].

PubMed

Etchepareborda, M C

1999-02-01

One of the commonest neurological development disorders is the syndrome of inattention with hyperactivity, ADHD. The complex neurobiological network which intervenes in paying attention permits us to maintain a basal state of alertness, to focalize and maintain attention for long periods, select the stimulus-signal required and analyze its components, and also to simultaneously carry out processes of input-output and performance (tutorial, controlling). Damage to the various systems participating in 'paying attention' leads to a syndrome of inattention, with or without hyperactivity. The distinction into clinical sub-types (combined, mainly lacking attention or mainly hyperactive and impulsive) gives a primary differentiation of the syndrome. However, from the neuropsychological point of view, some degree of heterogeneity within the groups which defines academic behaviour and conduct may also be recognized. This type of study permits a more specific neuro-cognitive and pharmacological approach. Some clinical characteristics of the syndrome of inattention improve with different drugs, such as the state of alterness (methylphenidate), impulsivity (pipamperone) and selective attention (tiapride). However, this treatment is symptomatic and in most cases is useful to accompany the ultimate biological development of the neocortical control mechanisms. A neuro-cognitive approach which permits acquisition of habits of control, functional strategies, sequential planning of activities and per- and post-functional surveillance is fundamental. The EFE programme for training executive functions is directed towards working with the damaged processing mechanisms in each neuropsychological subtype.

Mitochondrial targeting of XJB-5-131 attenuates or improves pathophysiology in HdhQ150 animals with well-developed disease phenotypes

DOE PAGES

Polyzos, Aris; Holt, Amy; Brown, Christopher; ...

2016-02-21

Oxidative damage to mitochondria (MT) is a major mechanism for aging and neurodegeneration. We have developed a novel synthetic antioxidant, XJB-5-131, which directly targets MT, the primary site and primary target of oxidative damage. XJB-5-131 prevents the onset of motor decline in an HdhQ(150/150) mouse model for Huntington's disease (HD) if treatment starts early. Here, we report that XJB-5-131 attenuates or reverses disease progression if treatment occurs after disease onset. In animals with well-developed pathology, XJB-5-131 promotes weight gain, prevents neuronal death, reduces oxidative damage in neurons, suppresses the decline of motor performance or improves it, and reduces a grayingmore » phenotype in treated HdhQ(150/150) animals relative to matched littermate controls. XJB-5-131 holds promise as a clinical candidate for the treatment of HD.« less

Design and evaluation of a foam-filled hat-stiffened panel concept for aircraft primary structural applications

NASA Technical Reports Server (NTRS)

Ambur, Damodar R.

1995-01-01

A structurally efficient hat-stiffened panel concept that utilizes a structural foam as stiffener core has been designed for aircraft primary structural applications. This stiffener concept utilizes a manufacturing process that can be adapted readily to grid-stiffened structural configurations which possess inherent damage tolerance characteristics due to their multiplicity of load paths. The foam-filled hat-stiffener concept in a prismatically stiffened panel configuration is more efficient than most other stiffened panel configurations in a load range that is typical for both fuselage and wing structures. The prismatically stiffened panel concept investigated here has been designed using AS4/3502 preimpregnated tape and Rohacell foam core and evaluated for its buckling and postbuckling behavior with and without low-speed impact damage. The results from single-stiffener and multi-stiffener specimens suggest that this structural concept responds to loading as anticipated and has good damage tolerance characteristics.

Mitochondrial targeting of XJB-5-131 attenuates or improves pathophysiology in HdhQ150 animals with well-developed disease phenotypes

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

Polyzos, Aris; Holt, Amy; Brown, Christopher

Oxidative damage to mitochondria (MT) is a major mechanism for aging and neurodegeneration. We have developed a novel synthetic antioxidant, XJB-5-131, which directly targets MT, the primary site and primary target of oxidative damage. XJB-5-131 prevents the onset of motor decline in an HdhQ(150/150) mouse model for Huntington's disease (HD) if treatment starts early. Here, we report that XJB-5-131 attenuates or reverses disease progression if treatment occurs after disease onset. In animals with well-developed pathology, XJB-5-131 promotes weight gain, prevents neuronal death, reduces oxidative damage in neurons, suppresses the decline of motor performance or improves it, and reduces a grayingmore » phenotype in treated HdhQ(150/150) animals relative to matched littermate controls. XJB-5-131 holds promise as a clinical candidate for the treatment of HD.« less

Brain-Specific Cytoskeletal Damage Markers in Cerebrospinal Fluid: Is There a Common Pattern between Amyotrophic Lateral Sclerosis and Primary Progressive Multiple Sclerosis?

PubMed

Abdelhak, Ahmed; Junker, Andreas; Brettschneider, Johannes; Kassubek, Jan; Ludolph, Albert C; Otto, Markus; Tumani, Hayrettin

2015-07-31

Many neurodegenerative disorders share a common pathophysiological pathway involving axonal degeneration despite different etiological triggers. Analysis of cytoskeletal markers such as neurofilaments, protein tau and tubulin in cerebrospinal fluid (CSF) may be a useful approach to detect the process of axonal damage and its severity during disease course. In this article, we review the published literature regarding brain-specific CSF markers for cytoskeletal damage in primary progressive multiple sclerosis and amyotrophic lateral sclerosis in order to evaluate their utility as a biomarker for disease progression in conjunction with imaging and histological markers which might also be useful in other neurodegenerative diseases associated with affection of the upper motor neurons. A long-term benefit of such an approach could be facilitating early diagnostic and prognostic tools and assessment of treatment efficacy of disease modifying drugs.

Brain-Specific Cytoskeletal Damage Markers in Cerebrospinal Fluid: Is There a Common Pattern between Amyotrophic Lateral Sclerosis and Primary Progressive Multiple Sclerosis?

PubMed Central

Abdelhak, Ahmed; Junker, Andreas; Brettschneider, Johannes; Kassubek, Jan; Ludolph, Albert C.; Otto, Markus; Tumani, Hayrettin

2015-01-01

Many neurodegenerative disorders share a common pathophysiological pathway involving axonal degeneration despite different etiological triggers. Analysis of cytoskeletal markers such as neurofilaments, protein tau and tubulin in cerebrospinal fluid (CSF) may be a useful approach to detect the process of axonal damage and its severity during disease course. In this article, we review the published literature regarding brain-specific CSF markers for cytoskeletal damage in primary progressive multiple sclerosis and amyotrophic lateral sclerosis in order to evaluate their utility as a biomarker for disease progression in conjunction with imaging and histological markers which might also be useful in other neurodegenerative diseases associated with affection of the upper motor neurons. A long-term benefit of such an approach could be facilitating early diagnostic and prognostic tools and assessment of treatment efficacy of disease modifying drugs. PMID:26263977

Output-Based Structural Damage Detection by Using Correlation Analysis Together with Transmissibility

PubMed Central

Cao, Hongyou; Liu, Quanmin; Wahab, Magd Abdel

2017-01-01

Output-based structural damage detection is becoming increasingly appealing due to its potential in real engineering applications without any restriction regarding excitation measurements. A new transmissibility-based damage detection approach is presented in this study by combining transmissibility with correlation analysis in order to strengthen its performance in discriminating damaged from undamaged scenarios. From this perspective, damage detection strategies are hereafter established by constructing damage-sensitive indicators from a derived transmissibility. A cantilever beam is numerically analyzed to verify the feasibility of the proposed damage detection procedure, and an ASCE (American Society of Civil Engineers) benchmark is henceforth used in the validation for its application in engineering structures. The results of both studies reveal a good performance of the proposed methodology in identifying damaged states from intact states. The comparison between the proposed indicator and the existing indicator also affirms its applicability in damage detection, which might be adopted in further structural health monitoring systems as a discrimination criterion. This study contributed an alternative criterion for transmissibility-based damage detection in addition to the conventional ones. PMID:28773218

Pure word deafness following left temporal damage: Behavioral and neuroanatomical evidence from a new case.

PubMed

Maffei, Chiara; Capasso, Rita; Cazzolli, Giulia; Colosimo, Cesare; Dell'Acqua, Flavio; Piludu, Francesca; Catani, Marco; Miceli, Gabriele

2017-12-01

Pure Word Deafness (PWD) is a rare disorder, characterized by selective loss of speech input processing. Its most common cause is temporal damage to the primary auditory cortex of both hemispheres, but it has been reported also following unilateral lesions. In unilateral cases, PWD has been attributed to the disconnection of Wernicke's area from both right and left primary auditory cortex. Here we report behavioral and neuroimaging evidence from a new case of left unilateral PWD with both cortical and white matter damage due to a relatively small stroke lesion in the left temporal gyrus. Selective impairment in auditory language processing was accompanied by intact processing of nonspeech sounds and normal speech, reading and writing. Performance on dichotic listening was characterized by a reversal of the right-ear advantage typically observed in healthy subjects. Cortical thickness and gyral volume were severely reduced in the left superior temporal gyrus (STG), although abnormalities were not uniformly distributed and residual intact cortical areas were detected, for example in the medial portion of the Heschl's gyrus. Diffusion tractography documented partial damage to the acoustic radiations (AR), callosal temporal connections and intralobar tracts dedicated to single words comprehension. Behavioral and neuroimaging results in this case are difficult to integrate in a pure cortical or disconnection framework, as damage to primary auditory cortex in the left STG was only partial and Wernicke's area was not completely isolated from left or right-hemisphere input. On the basis of our findings we suggest that in this case of PWD, concurrent partial topological (cortical) and disconnection mechanisms have contributed to a selective impairment of speech sounds. The discrepancy between speech and non-speech sounds suggests selective damage to a language-specific left lateralized network involved in phoneme processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Laser Damage and Effects Bibliography. Part 1. Journal Literature through 1982

DTIC Science & Technology

1984-06-15

F.; BROST , George ; SCHMID, Ansgar; KELLY, P. J. "The Role of Laser-Induced Primary Defect Formation in Optical Breakdown of NaCl" IEEE J. Quantum...Induced Damage in Optical Materials: 1980, Nat. Bur. Stands. (U.S.), Spec. ubl. 620 (Oct 81) 403-405 BRAUNLICH, Peter F.; BROST , George ; SCHMID...James; RITTER, George J. "Laser-Induced Damage in Copper Crystals" Appl. Phys. Lett. 9 (1 Oct 66) 272-273 PERESSINI, E. H. "Field Emission from Atoms in

Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970

PubMed Central

Boucher, Diane M.; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A.; Milton, Sean; Murphy, Cheryl E.; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M.; Pollard, John R.

2014-01-01

Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients. PMID:25010037

Potentiation of tumor responses to DNA damaging therapy by the selective ATR inhibitor VX-970.

PubMed

Hall, Amy B; Newsome, Dave; Wang, Yuxin; Boucher, Diane M; Eustace, Brenda; Gu, Yong; Hare, Brian; Johnson, Mac A; Milton, Sean; Murphy, Cheryl E; Takemoto, Darin; Tolman, Crystal; Wood, Mark; Charlton, Peter; Charrier, Jean-Damien; Furey, Brinley; Golec, Julian; Reaper, Philip M; Pollard, John R

2014-07-30

Platinum-based DNA-damaging chemotherapy is standard-of-care for most patients with lung cancer but outcomes remain poor. This has been attributed, in part, to the highly effective repair network known as the DNA-damage response (DDR). ATR kinase is a critical regulator of this pathway, and its inhibition has been shown to sensitize some cancer, but not normal, cells in vitro to DNA damaging agents. However, there are limited in vivo proof-of-concept data for ATR inhibition. To address this we profiled VX-970, the first clinical ATR inhibitor, in a series of in vitro and in vivo lung cancer models and compared it with an inhibitor of the downstream kinase Chk1. VX-970 markedly sensitized a large proportion of a lung cancer cell line and primary tumor panel in vitro to multiple DNA damaging drugs with clear differences to Chk1 inhibition observed. In vivo VX-970 blocked ATR activity in tumors and dramatically enhanced the efficacy of cisplatin across a panel of patient derived primary lung xenografts. The combination led to complete tumor growth inhibition in three cisplatin-insensitive models and durable tumor regression in a cisplatin-sensitive model. These data provide a strong rationale for the clinical evaluation of VX-970 in lung cancer patients.

Intrusive luxation in primary teeth – Review of literature and report of a case

PubMed Central

Gupta, Megha

2011-01-01

Luxation injuries such as intrusion are commonly seen in the primary dentition. Intrusion drives the tooth deeper into the alveolar socket, which results in damage to the pulp and peridontium. Difficulty in gaining compliance from a very young child and the risk of damaging the permanent tooth germ makes the management of these injuries challenging. Careful clinical and radiographic examination along with regular follow-up is essential. A case of intrusive luxation to the maxillary central incisor in a 3-year-old patient is reported. Spontaneous reeruption was noted 4 months after injury, but the tooth had developed an abscess and external root resorption. Hence, extraction of the tooth was done and an anterior esthetic fixed space maintainer was placed. Traumatic injuries to the primary dentition should not be ignored by the parents or by the dentist. The paper also includes a literature review of intrusive luxation in the primary dentition. PMID:23960512

Development of hazard-compatible building fragility and vulnerability models

USGS Publications Warehouse

Karaca, E.; Luco, N.

2008-01-01

We present a methodology for transforming the structural and non-structural fragility functions in HAZUS into a format that is compatible with conventional seismic hazard analysis information. The methodology makes use of the building capacity (or pushover) curves and related building parameters provided in HAZUS. Instead of the capacity spectrum method applied in HAZUS, building response is estimated by inelastic response history analysis of corresponding single-degree-of-freedom systems under a large number of earthquake records. Statistics of the building response are used with the damage state definitions from HAZUS to derive fragility models conditioned on spectral acceleration values. Using the developed fragility models for structural and nonstructural building components, with corresponding damage state loss ratios from HAZUS, we also derive building vulnerability models relating spectral acceleration to repair costs. Whereas in HAZUS the structural and nonstructural damage states are treated as if they are independent, our vulnerability models are derived assuming "complete" nonstructural damage whenever the structural damage state is complete. We show the effects of considering this dependence on the final vulnerability models. The use of spectral acceleration (at selected vibration periods) as the ground motion intensity parameter, coupled with the careful treatment of uncertainty, makes the new fragility and vulnerability models compatible with conventional seismic hazard curves and hence useful for extensions to probabilistic damage and loss assessment.

Analysis of a nuclear accident: fission and activation product releases from the Fukushima Daiichi nuclear facility as remote indicators of source identification, extent of release, and state of damaged spent nuclear fuel.

PubMed

Schwantes, Jon M; Orton, Christopher R; Clark, Richard A

2012-08-21

Researchers evaluated radionuclide measurements of environmental samples taken from the Fukushima Daiichi nuclear facility and reported on the Tokyo Electric Power Co. Website following the 2011 tsunami-initiated catastrophe. This effort identified Units 1 and 3 as the major source of radioactive contamination to the surface soil near the facility. Radionuclide trends identified in the soils suggested that: (1) chemical volatility driven by temperature and reduction potential within the vented reactors' primary containment vessels dictated the extent of release of radiation; (2) all coolant had likely evaporated by the time of venting; and (3) physical migration through the fuel matrix and across the cladding wall were minimally effective at containing volatile species, suggesting damage to fuel bundles was extensive. Plutonium isotopic ratios and their distance from the source indicated that the damaged reactors were the major contributor of plutonium to surface soil at the source, decreasing rapidly with distance from the facility. Two independent evaluations estimated the fraction of the total plutonium inventory released to the environment relative to cesium from venting Units 1 and 3 to be ∼0.002-0.004%. This study suggests significant volatile radionuclides within the spent fuel at the time of venting, but not as yet observed and reported within environmental samples, as potential analytes of concern for future environmental surveys around the site. The majority of the reactor inventories of isotopes of less volatile elements like Pu, Nb, and Sr were likely contained within the damaged reactors during venting.

Ultraviolet-induced sister chromatid exchanges in V-79 cells with normal and BrdUrd-substituted DNA and the influence of intercalating substances and cysteine

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

Speit, G.; Mehnert, K.; Wolf, M.

1982-06-01

The influence of intercalating substances (proflavine, ethidium bromide) and of an SH compound (L-cysteine) on uv-induced sister chromatid exchanges (SCEs) was investigated in V-79 cells with normal and BrdUrd-substituted DNA. The results are discussed in relation to the primary damages leading to SCE induction produced by uv irradiation. The data indicate that neither the pyrimidine dimers nor DNA single-strand breaks are the primary cause of SCE induction, and that the damages leading to SCEs by uv irradiation differ from those which cause chromosome aberrations.

The cost of karst subsidence and sinkhole collapse in the United States compared with other natural hazards

USGS Publications Warehouse

Weary, David J.

2015-01-01

Rocks with potential for karst formation are found in all 50 states. Damage due to karst subsidence and sinkhole collapse is a natural hazard of national scope. Repair of damage to buildings, highways, and other infrastructure represents a significant national cost. Sparse and incomplete data show that the average cost of karst-related damages in the United States over the last 15 years is estimated to be at least $300,000,000 per year and the actual total is probably much higher. This estimate is lower than the estimated annual costs for other natural hazards; flooding, hurricanes and cyclonic storms, tornadoes, landslides, earthquakes, or wildfires, all of which average over $1 billion per year. Very few state organizations track karst subsidence and sinkhole damage mitigation costs; none occurs at the Federal level. Many states discuss the karst hazard in their State hazard mitigation plans, but seldom include detailed reports of subsidence incidents or their mitigation costs. Most State highway departments do not differentiate karst subsidence or sinkhole collapse from other road repair costs. Amassing of these data would raise the estimated annual cost considerably. Information from insurance organizations about sinkhole damage claims and payouts is also not readily available. Currently there is no agency with a mandate for developing such data. If a more realistic estimate could be made, it would illuminate the national scope of this hazard and make comparison with costs of other natural hazards more realistic.

Comparisons Between Total Lightning Data, Mesocyclone Strength, and Storm Damage Associated with the Florida Tornado Outbreak of February 23, 1998

NASA Technical Reports Server (NTRS)

Hodanish, S; Sharp, D.; Williams, E.; Boldi, B.; Goodman, Steven J.; Raghavan, R.; Matlin, A.; Weber, M.

1998-01-01

During the early morning hours of February 23 1998, the worst tornado outbreak ever recorded occurred over the central Florida peninsula. At least 7 confirmed tornadoes, associated with 4 supercells, developed, with 3 of the tornadoes reaching F3 intensity. Many of the tornadoes where on the ground for tens of miles, uncommon for the state of Florida. A total of 42 people were killed, with over 250 people injured. During the outbreak, National Weather Service Melbourne, in collaboration with the National Aeronautics and Space Administration and the Massachusetts Institute of Technology was collecting data from a unique lightning observing system called Lightning Imaging Sensor Data Applications Display (LISDAD, Boldi et.al., this conference). This system marries radar data collected from the KMLB WSR-88D, cloud to ground data collected from the National Lightning Detection Network, and total lightning data collected from NASKs Lightning Detection And Ranging system. This poster will display, concurrently, total lightning data (displayed in 1 minute increments), time/height storm relative velocity products from the KMLB WSR-88D, and damage information (tornado/hail/wind) from each of the supercell thunderstorms. The primary objective of this poster presentation is to observe how total lightning activity changes as the convective storm intensifies, and how the lightning activity changes with respect to mesocyclone strength (vortex stretching) and damaging weather on the ground.

Predictions of Poisson's ratio in cross-ply laminates containing matrix cracks and delaminations

NASA Technical Reports Server (NTRS)

Harris, Charles E.; Allen, David H.; Nottorf, Eric W.

1989-01-01

A damage-dependent constitutive model for laminated composites has been developed for the combined damage modes of matrix cracks and delaminations. The model is based on the concept of continuum damage mechanics and uses second-order tensor valued internal state variables to represent each mode of damage. The internal state variables are defined as the local volume average of the relative crack face displacements. Since the local volume for delaminations is specified at the laminate level, the constitutive model takes the form of laminate analysis equations modified by the internal state variables. Model implementation is demonstrated for the laminate engineering modulus E(x) and Poisson's ratio nu(xy) of quasi-isotropic and cross-ply laminates. The model predictions are in close agreement to experimental results obtained for graphite/epoxy laminates.

Dynamic deformation and fracture of single crystal silicon: Fracture modes, damage laws, and anisotropy

DOE PAGES

Huang, J. Y.; E, J. C.; Huang, J. W.; ...

2016-05-25

Impact fracture of single-crystal Si is critical to long-term reliability of electronic devices and solar cells for its wide use as components or substrates in semiconductor industry. Single-crystal Si is loaded along two different crystallographic directions with a split Hopkinson pressure bar integrated with an in situ x-ray imaging and diffraction system. Bulk stress histories are measured, simultaneously with x-ray phase contrast imaging (XPCI) and Laue diffraction. Damage evolution is quantified with grayscale maps from XPCI. Single-crystal Si exhibits pronounced anisotropy in fracture modes, and thus fracture strengths and damage evolution. For loading along [11¯ 0] and viewing along [001],more » (1¯1¯0)[11¯ 0] cleavage is activated and induces horizontal primary cracks followed by perpendicular wing cracks. However, for loading along [011¯] and viewing along [111], random nucleation and growth of shear and tensile-splitting crack networks lead to catastrophic failure of materials with no cleavage. The primary-wing crack mode leads to a lower characteristic fracture strength due to predamage, but a more concentrated strength distribution, i.e., a higher Weibull modulus, compared to the second loading case. Furthermore, the sequential primary cracking, wing cracking and wing-crack coalescence processes result in a gradual increase of damage with time, deviating from theoretical predictions. Particle size and aspect ratios of fragments are discussed with postmortem fragment analysis, which verifies fracture modes observed in XPCI.« less

OBJECT KINETIC MONTE CARLO SIMULATIONS OF RADIATION DAMAGE IN TUNGSTEN SUBJECTED TO NEUTRON FLUX WITH PKA SPECTRUM CORRESPONDING TO THE HFIR

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

Nandipati, Giridhar; Setyawan, Wahyu; Heinisch, Howard L.

2015-12-31

The objective of this work is to study the damage accumulation in pure tungsten (W) subjected to neutron bombardment with a primary knock-on atom (PKA) spectrum corresponding to the High Flux Isotope Reactor (HFIR), using the object kinetic Monte Carlo (OKMC) method.

Pilot simulation tests of propulsion control as backup to loss of primary flight controls for a mid-size jet transport

DOT National Transportation Integrated Search

1995-12-01

Partial failures of aircraft primary flight-control systems and structural : damages to aircraft during flight have led to catastrophic accidents with : subsequent loss of life. These accidents can be prevented if sufficient : alternate control autho...

Data-Enabled Quantification of Aluminum Microstructural Damage Under Tensile Loading

NASA Astrophysics Data System (ADS)

Wayne, Steven F.; Qi, G.; Zhang, L.

2016-08-01

The study of material failure with digital analytics is in its infancy and offers a new perspective to advance our understanding of damage initiation and evolution in metals. In this article, we study the failure of aluminum using data-enabled methods, statistics and data mining. Through the use of tension tests, we establish a multivariate acoustic-data matrix of random damage events, which typically are not visible and are very difficult to measure due to their variability, diversity and interactivity during damage processes. Aluminium alloy 6061-T651 and single crystal aluminium with a (111) orientation were evaluated by comparing the collection of acoustic signals from damage events caused primarily by slip in the single crystal and multimode fracture of the alloy. We found the resulting acoustic damage-event data to be large semi-structured volumes of Big Data with the potential to be mined for information that describes the materials damage state under strain. Our data-enabled analyses has allowed us to determine statistical distributions of multiscale random damage that provide a means to quantify the material damage state.

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

Xu, W.; Zhu, W. D.; Smith, S. A.

While structural damage detection based on flexural vibration shapes, such as mode shapes and steady-state response shapes under harmonic excitation, has been well developed, little attention is paid to that based on longitudinal vibration shapes that also contain damage information. This study originally formulates a slope vibration shape for damage detection in bars using longitudinal vibration shapes. To enhance noise robustness of the method, a slope vibration shape is transformed to a multiscale slope vibration shape in a multiscale domain using wavelet transform, which has explicit physical implication, high damage sensitivity, and noise robustness. These advantages are demonstrated in numericalmore » cases of damaged bars, and results show that multiscale slope vibration shapes can be used for identifying and locating damage in a noisy environment. A three-dimensional (3D) scanning laser vibrometer is used to measure the longitudinal steady-state response shape of an aluminum bar with damage due to reduced cross-sectional dimensions under harmonic excitation, and results show that the method can successfully identify and locate the damage. Slopes of longitudinal vibration shapes are shown to be suitable for damage detection in bars and have potential for applications in noisy environments.« less

Research on Characterization of Damage States in Continuous Fiber Composites Using Ultrasonic Nondestructive Evaluation.

DTIC Science & Technology

1986-05-01

Composites Using Ultrasonic Nondestructive Evaluation Annual Technical Report I by Vikrai K. Kinra Depdrtment of Aerospace Engineering r and Mechanics...and identify by b ko number) 7It is well known that composite materials suffer complex damage when they are.-ub- jected to either monotonic or...Characterization of Damage States in Continuous Fiber Composites Using Ultrasonic Nondestructive Evaluation Annual Technical Report by Vikram K. Kinra Department

Feasibility Investigation into Strengthening of Timber Bridge Stringers

DTIC Science & Technology

2007-05-01

life . They exhibit several types of damage, which occurs in their structural elements such as timber stringers. The most commonly encountered damage...United States are nearing, or at the end of their service life , which means they exhibit several types of damage. This occurs mostly on structural... life of a timber bridge is approximately 30–40 years, the majority of timber bridges in the United States are nearing the end of their service life

Compressive residual strength of graphite/epoxy laminates after impact

NASA Technical Reports Server (NTRS)

Guy, Teresa A.; Lagace, Paul A.

1992-01-01

The issue of damage tolerance after impact, in terms of the compressive residual strength, was experimentally examined in graphite/epoxy laminates using Hercules AS4/3501-6 in a (+ or - 45/0)(sub 2S) configuration. Three different impactor masses were used at various velocities and the resultant damage measured via a number of nondestructive and destructive techniques. Specimens were then tested to failure under uniaxial compression. The results clearly show that a minimum compressive residual strength exists which is below the open hole strength for a hole of the same diameter as the impactor. Increases in velocity beyond the point of minimum strength cause a difference in the damage produced and cause a resultant increase in the compressive residual strength which asymptotes to the open hole strength value. Furthermore, the results show that this minimum compressive residual strength value is independent of the impactor mass used and is only dependent upon the damage present in the impacted specimen which is the same for the three impactor mass cases. A full 3-D representation of the damage is obtained through the various techniques. Only this 3-D representation can properly characterize the damage state that causes the resultant residual strength. Assessment of the state-of-the-art in predictive analysis capabilities shows a need to further develop techniques based on the 3-D damage state that exists. In addition, the need for damage 'metrics' is clearly indicated.

Damage of photoreceptor-derived cells in culture induced by light emitting diode-derived blue light

PubMed Central

Kuse, Yoshiki; Ogawa, Kenjiro; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Hara, Hideaki

2014-01-01

Our eyes are increasingly exposed to light from the emitting diode (LED) light of video display terminals (VDT) which contain much blue light. VDTs are equipped with televisions, personal computers, and smart phones. The present study aims to clarify the mechanism underlying blue LED light-induced photoreceptor cell damage. Murine cone photoreceptor-derived cells (661 W) were exposed to blue, white, or green LED light (0.38 mW/cm2). In the present study, blue LED light increased reactive oxygen species (ROS) production, altered the protein expression level, induced the aggregation of short-wavelength opsins (S-opsin), resulting in severe cell damage. While, blue LED light damaged the primary retinal cells and the damage was photoreceptor specific. N-Acetylcysteine (NAC), an antioxidant, protected against the cellular damage induced by blue LED light. Overall, the LED light induced cell damage was wavelength-, but not energy-dependent and may cause more severe retinal photoreceptor cell damage than the other LED light. PMID:24909301

A new method to assess damage to RCMRFs from period elongation and Park-Ang damage index using IDA

NASA Astrophysics Data System (ADS)

Aghagholizadeh, Mehrdad; Massumi, Ali

2016-09-01

Despite a significant progress in loading and design codes of seismic resistant structures and technology improvements in building structures, the field of civil engineering is still facing critical challenges. An example of those challenges is the assessment of the state of damage that has been imposed to a structure after earthquakes of different intensities. To determine the operability of a structure and its resistance to probable future earthquakes, quick assessment of damages and determining the operability of a structure after an earthquake are crucial. Present methods to calculate damage to structures are time consuming and do not accurately provide the rate of damage. Damage estimation is important task in the fields of structural health monitoring and decision-making. This study examines the relationship between period elongation and the Park-Ang damage index. A dynamic non-linear analysis is employed with IDARC program to calculate the amount of damage and period of the current state. This new method is shown to be a quick and accurate technique for damage assessment. It is easy to calculate the period of an existing structure and changes in the period which reflects changes in the stiffness matrix.

Structural Damage Detection Using Slopes of Longitudinal Vibration Shapes

DOE PAGES

Xu, W.; Zhu, W. D.; Smith, S. A.; ...

2016-03-18

While structural damage detection based on flexural vibration shapes, such as mode shapes and steady-state response shapes under harmonic excitation, has been well developed, little attention is paid to that based on longitudinal vibration shapes that also contain damage information. This study originally formulates a slope vibration shape for damage detection in bars using longitudinal vibration shapes. To enhance noise robustness of the method, a slope vibration shape is transformed to a multiscale slope vibration shape in a multiscale domain using wavelet transform, which has explicit physical implication, high damage sensitivity, and noise robustness. These advantages are demonstrated in numericalmore » cases of damaged bars, and results show that multiscale slope vibration shapes can be used for identifying and locating damage in a noisy environment. A three-dimensional (3D) scanning laser vibrometer is used to measure the longitudinal steady-state response shape of an aluminum bar with damage due to reduced cross-sectional dimensions under harmonic excitation, and results show that the method can successfully identify and locate the damage. Slopes of longitudinal vibration shapes are shown to be suitable for damage detection in bars and have potential for applications in noisy environments.« less

50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

Code of Federal Regulations, 2010 CFR

2010-10-01

... affixed to containers prior to export or re-export in accordance with this paragraph. (1) The following... without being damaged or transferred to another container. (ii) Primary container means any container in direct contact with the caviar. (iii) Secondary container means the receptacle into which primary...

50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

Code of Federal Regulations, 2011 CFR

2011-10-01

... affixed to containers prior to export or re-export in accordance with this paragraph. (1) The following... without being damaged or transferred to another container. (ii) Primary container means any container in direct contact with the caviar. (iii) Secondary container means the receptacle into which primary...

50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

Code of Federal Regulations, 2013 CFR

2013-10-01

... affixed to containers prior to export or re-export in accordance with this paragraph. (1) The following... without being damaged or transferred to another container. (ii) Primary container means any container in direct contact with the caviar. (iii) Secondary container means the receptacle into which primary...

A Damage-Dependent Finite Element Analysis for Fiber-Reinforced Composite Laminates

NASA Technical Reports Server (NTRS)

Coats, Timothy W.; Harris, Charles E.

1998-01-01

A progressive damage methodology has been developed to predict damage growth and residual strength of fiber-reinforced composite structure with through penetrations such as a slit. The methodology consists of a damage-dependent constitutive relationship based on continuum damage mechanics. Damage is modeled using volume averaged strain-like quantities known as internal state variables and is represented in the equilibrium equations as damage induced force vectors instead of the usual degradation and modification of the global stiffness matrix.

Stochastic annealing simulations of defect interactions among subcascades

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

Heinisch, H.L.; Singh, B.N.

1997-04-01

The effects of the subcascade structure of high energy cascades on the temperature dependencies of annihilation, clustering and free defect production are investigated. The subcascade structure is simulated by closely spaced groups of lower energy MD cascades. The simulation results illustrate the strong influence of the defect configuration existing in the primary damage state on subsequent intracascade evolution. Other significant factors affecting the evolution of the defect distribution are the large differences in mobility and stability of vacancy and interstitial defects and the rapid one-dimensional diffusion of small, glissile interstitial loops produced directly in cascades. Annealing simulations are also performedmore » on high-energy, subcascade-producing cascades generated with the binary collision approximation and calibrated to MD results.« less

Detection and Characterization of Stress Symptoms in Forest Vegetation

NASA Technical Reports Server (NTRS)

Heller, R. C.

1971-01-01

Techniques used at the Pacific Southwest Forest and Range Experiment Station to detect advanced and previsual symptoms of vegetative stress are discussed. Stresses caused by bark beetles in coniferous stands of timber are emphasized because beetles induce stress more rapidly than most other destructive agents. Bark beetles are also the most damaging forest insects in the United States. In the work on stress symptoms, there are two primary objectives: (1) to learn the best combination of films, scales, and filters to detect and locate injured trees from aircraft and spacecraft, and (2) to learn if stressed trees can be detected before visual symptoms of decline occur. Equipment and techniques used in a study of the epidemic of the Black Hills bark beetle are described.

A Methodology for Forecasting Damage & Economic Consequences to Floods: Building on the National Flood Interoperability Experiment (NFIE)

NASA Astrophysics Data System (ADS)

Tootle, G. A.; Gutenson, J. L.; Zhu, L.; Ernest, A. N. S.; Oubeidillah, A.; Zhang, X.

2015-12-01

The National Flood Interoperability Experiment (NFIE) held June 3-July 17, 2015 at the National Water Center (NWC) in Tuscaloosa, Alabama sought to demonstrate an increase in flood predictive capacity for the coterminous United States (CONUS). Accordingly, NFIE-derived technologies and workflows offer the ability to forecast flood damage and economic consequence estimates that coincide with the hydrologic and hydraulic estimations these physics-based models generate. A model providing an accurate prediction of damage and economic consequences is a valuable asset when allocating funding for disaster response, recovery, and relief. Damage prediction and economic consequence assessment also offer an adaptation planning mechanism for defending particularly valuable or vulnerable structures. The NFIE, held at the NWC on The University of Alabama (UA) campus led to the development of this large scale flow and inundation forecasting framework. Currently, the system can produce 15-hour lead-time forecasts for the entire coterminous United States (CONUS). A concept which is anticipated to become operational as of May 2016 within the NWC. The processing of such a large-scale, fine resolution model is accomplished in a parallel computing environment using large supercomputing clusters. Traditionally, flood damage and economic consequence assessment is calculated in a desktop computing environment with a ménage of meteorology, hydrology, hydraulic, and damage assessment tools. In the United States, there are a range of these flood damage/ economic consequence assessment software's available to local, state, and federal emergency management agencies. Among the more commonly used and freely accessible models are the Hydrologic Engineering Center's Flood Damage Reduction Analysis (HEC-FDA), Flood Impact Assessment (HEC-FIA), and Federal Emergency Management Agency's (FEMA's) United States Multi-Hazard (Hazus-MH). All of which exist only in a desktop environment. With this, authors submit an initial framework for estimating damage and economic consequences to floods using flow and inundation products from the NFIE framework. This adaptive system utilizes existing nationwide datasets describing location and use of structures and can take assimilate a range of data resolutions.

Primary Biliary Cholangitis: advances in management and treatment of the disease.

PubMed

Invernizzi, Pietro; Floreani, Annarosa; Carbone, Marco; Marzioni, Marco; Craxi, Antonio; Muratori, Luigi; Vespasiani Gentilucci, Umberto; Gardini, Ivan; Gasbarrini, Antonio; Kruger, Paola; Mennini, Francesco Saverio; Ronco, Virginia; Lanati, Elena; Canonico, Pier Luigi; Alvaro, Domenico

2017-08-01

Primary Biliary Cholangitis, previously known as Primary Biliary Cirrhosis, is a rare disease, which mainly affects women in their fifth to seventh decades of life. It is a chronic autoimmune disease characterized by a progressive damage of interlobular bile ducts leading to ductopenia, chronic cholestasis and bile acids retention. Even if the disease usually presents a long asymptomatic phase and a slow progression, in many patients it may progress faster toward cirrhosis and its complications. The 10year mortality is greater than in diseases such as human immunodeficiency virus/Hepatitis C Virus coinfection and breast cancer. Ursodeoxycholic acid is the only treatment available today, but even if effective in counteracting the disease progression for the majority of patients, in approximately 40% is not able to decrease effectively the alkaline phosphatase, a surrogate marker of disease activity. Recently, obeticholic acid received the European Medicines Agency conditional approval, as add on treatment in patients non responders or intolerant to ursodeoxycholic acid. The present paper illustrates the opinion of a working group, composed by clinical pharmacologists, gastroenterologists/hepatologists with specific expertise on Primary Biliary Cholangitis and patient associations, on the state of the art and future perspectives of the disease management. The agreement on the document was reached through an Expert Meeting. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Thrips pests of China and the United States

USDA-ARS?s Scientific Manuscript database

Thrips are among the most significant agricultural pests in China and the United States. Thrips can damage crops by their direct feeding and oviposition damage, and by the ability of some species to vector plant viruses. Four highly invasive species, Frankliniella occidentalis (Pergande), Scirtoth...

Structural damages observed in state buildings after Simav/Turkey earthquake occurred on 19 May 2011

NASA Astrophysics Data System (ADS)

Tama, Y. S.

2012-08-01

Different levels of damages occurred in state buildings, especially in educational facilities, during the Simav earthquake (ML=5.7) on 19 May 2011. A site survey was carried out in the area after the earthquake, where six state buildings were examined in detail. The results of the survey showed that main reasons for the formation of damages in these buildings are the use of low strength concrete, insufficient reinforcement, inappropriate detailing, and low-quality workmanship. The investigated buildings were also evaluated by P25-rapid assessment method. The method demonstrates that two of the buildings in question are in "high risk band"; the other two fall into "detailed evaluation band", and the rest are in the "low risk band". This figure also matches with the damages observed in the site survey.

Ecosystem Responses To Plant Phenology Across Scales And Trophic Levels

NASA Astrophysics Data System (ADS)

Stoner, D.; Sexton, J. O.; Nagol, J. R.; Ironside, K.; Choate, D.; Longshore, K.; Edwards, T., Jr.

2015-12-01

Plant phenology in arid and semi-arid ecoregions is constrained by water availability and governs the life history characteristics of primary and secondary consumers. We related the behavior, demography, and distribution of mammalian herbivores and their principal predator to remotely sensed vegetation and climatological indices across the western United States for the period 2000-2014. Across scales, terrain and topographic position moderates the effects of climatological drought on primary productivity, resulting in differential susceptibility among plant functional types to water stress. At broad scales, herbivores tie parturition to moist sites during the period of maximum increase in local forage production. Consequently, juvenile mortality is highest in regions of extreme phenological variability. Although decoupled from primary production by one or more trophic levels, carnivore home range size and density is negatively correlated to plant productivity and growing season length. At the finest scales, predation influences the behavior of herbivore prey through compromised habitat selection, in which maternal females trade nutritional benefits of high plant biomass for reduced mortality risk associated with increased visibility. Climate projections for the western United States predict warming combined with shifts in the timing and form of precipitation. Our analyses suggest that these changes will propagate through trophic levels as increased phenological variability and shifts in plant distributions, larger consumer home ranges, altered migration behavior, and generally higher volatility in wildlife populations. Combined with expansion and intensification of human land use across the region, these changes will likely have economic implications stemming from increased human-wildlife conflict (e.g., crop damage, vehicle collisions) and changes in wildlife-related tourism.

Three essays on utility regulation

NASA Astrophysics Data System (ADS)

Hlasny, Vladimir

To induce utilities in the gas distribution market to operate efficiently, US states have deployed consumer choice programs, price caps, and variations of sliding scale plans. My first essay studies the impact of these restructuring and deregulation efforts on consumer rates, using panel data from a custom survey of state commissions and the Department of Energy. I estimate the residential, small commercial and industrial price equations jointly, and use instrumental variables to control for the potentially endogenous demand and status of deregulation. Consumer choice programs lower the prices by 2.2-20.1% compared to the rate of return regulation, benefiting industrial consumers the most and households the least. These effects appear even one to two years prior to the programs' implementation, and become stronger over time. Price caps lower all prices by 0.0-20.0%, with the same ranking. The impacts of sliding scale plans are close to zero, between -2.6% and +4.0% The second paper evaluates health damages caused by air concentrations of SO2 under three alternative environmental policies leading to identical aggregate emissions: emission caps, a nationwide emission tax, and a system of tradable emission allowances such as the one currently used in the US. The numerical model of the industry finds generators' output, participation in energy trade and SO2 abatement effort under each policy. The resulting SO2 concentrations are used to derive the aggregate health damages using estimates in the medical literature. SO2 concentrations vary across policies even when the aggregate emissions are the same. These variations translate into substantially different losses for any individual state, and, nationwide, to hundreds of millions of dollars of difference in aggregate damages. Emission caps are found to lead to the lowest damages, outperforming the currently used system of allowances by 452 million. A uniform emission tax leads to very similar damages as the system of tradable allowances, in agreement with the theory. These results are consistent with prior academic studies, that emission allowances and uniform taxes may lead to higher damages than regulatory instruments that control regional emissions more closely. In terms of SO2 concentrations and health impacts, emission caps are shown to favor the southern and southeastern states, where they deliver 840 million lower damages than the system of allowances or an emission tax, while they deliver 390 million higher damages in the northern and northeastern states. In the third essay I compute health damages from SO2 under different assumptions on the relationship between the concentration levels and their marginal health impacts. I evaluate SO2 concentration profiles resulting under the three policies in the previous chapter. Using the ranges of marginal damage estimates in medical literature, emission caps are shown to lead to the lowest damages under all considered slopes, although their benefit over the system of tradable allowances falls as the slope of the marginal damage function increases. With the maxiμm slope consistent with current medical data, the savings in damages under the emission caps in the southern states fall to 670 million compared the system of allowances, while the excess in damages they cause in the north and the northeast rises to $600 million.

5.0 Monitoring methods for forests vulnerable to non-native invasive pest species

Treesearch

David W. Williams; Michael E. Montgomery; Kathleen S. Shields; Richard A. Evans

2008-01-01

Non-native invasive species pose a serious threat to forest resources, requiring programs to monitor their spatial spread and the damage they inflict on forest ecosystems. Invasive species research in the Delaware River Basin (DRB) had three primary objectives: to develop and evaluate monitoring protocols for selected pests and resulting ecosystem damage at the IMRAs...

Beliefs and practices regarding childhood fever among parents: a cross-sectional study from Palestine

PubMed Central

2013-01-01

Background Fever is an extremely common occurrence in paediatric patients and the most common cause for a child to be taken to the doctor. The literature indicates that parents have too many misconceptions and conflicting information about fever management. The aim of this study was to identify parents’ beliefs and practices regarding childhood fever management. Methods We conducted a cross-sectional survey among parents whose children were enrolled and presented for health care at primary health care clinics in the Nablus region of Palestine. Data were collected using structured questionnaire interviews with parents. The questionnaire consisted of ‘yes/no’ responses and multiple-response questions. Descriptive statistics were used. Results Overall, 402 parents were interviewed. All parents believed that fever could cause at least one harmful effect if left untreated. The harmful effects most frequently reported by parents were brain damage (38.1%), dehydration (15.7%), and other organs damage such as liver and kidney damage (14.2%). The study showed that 65.4% of parents would recognise fever by only touching the child, 31.6% would measure the temperature and 3.0% would assess temperature by touching and measuring the child. Antipyretic was preferred to be used by 34.8% of parents, while 49.8% stated that they preferred cold sponges, and 3.2% stated that they preferred homeopathic methods to treat fever. The most common factors influencing frequency of medication administration included physician’s instruction (61.7%), the degree of elevated temperature (14.9%) and instructions on the medication leaflet (13.7%). Of the participant parents, 53.2% believed antipyretics used to reduce fever were harmful. Parents reported the most harmful outcomes from these antipyretics to be allergic reactions (20.9%), effects on the stomach (16.9%), kidney damage (16.2%) and overdose (11.4%). Conclusions Parents were anxious when dealing with a feverish child, which resulted in incorrect or inappropriate practices. Parents require reliable evidence-based information about the care of feverish children. These results indicate a need to develop and evaluate educational programs in our setting that will provide parents with education on fever and fever management. PMID:23622106

Regeneration and replacement in the vertebrate inner ear.

PubMed

Matsui, Jonathan I; Parker, Mark A; Ryals, Brenda M; Cotanche, Douglas A

2005-10-01

Deafness affects more than 40 million people in the UK and the USA, and many more world-wide. The primary cause of hearing loss is damage to or death of the sensory receptor cells in the inner ear, the hair cells. Birds can readily regenerate their cochlear hair cells but the mammalian cochlea has shown no ability to regenerate after damage. Current research efforts are focusing on gene manipulation, gene therapy and stem cell transplantation for repairing or replacing damaged mammalian cochlear hair cells, which could lead to therapies for treating deafness in humans.

Written language impairments in primary progressive aphasia: a reflection of damage to central semantic and phonological processes.

PubMed

Henry, Maya L; Beeson, Pélagie M; Alexander, Gene E; Rapcsak, Steven Z

2012-02-01

Connectionist theories of language propose that written language deficits arise as a result of damage to semantic and phonological systems that also support spoken language production and comprehension, a view referred to as the "primary systems" hypothesis. The objective of the current study was to evaluate the primary systems account in a mixed group of individuals with primary progressive aphasia (PPA) by investigating the relation between measures of nonorthographic semantic and phonological processing and written language performance and by examining whether common patterns of cortical atrophy underlie impairments in spoken versus written language domains. Individuals with PPA and healthy controls were administered a language battery, including assessments of semantics, phonology, reading, and spelling. Voxel-based morphometry was used to examine the relation between gray matter volumes and language measures within brain regions previously implicated in semantic and phonological processing. In accordance with the primary systems account, our findings indicate that spoken language performance is strongly predictive of reading/spelling profile in individuals with PPA and suggest that common networks of critical left hemisphere regions support central semantic and phonological processes recruited for spoken and written language.

Diffusion Tensor Imaging Reveals White Matter Injury in a Rat Model of Repetitive Blast-Induced Traumatic Brain Injury

PubMed Central

Calabrese, Evan; Du, Fu; Garman, Robert H.; Johnson, G. Allan; Riccio, Cory; Tong, Lawrence C.

2014-01-01

Abstract Blast-induced traumatic brain injury (bTBI) is one of the most common combat-related injuries seen in U.S. military personnel, yet relatively little is known about the underlying mechanisms of injury. In particular, the effects of the primary blast pressure wave are poorly understood. Animal models have proven invaluable for the study of primary bTBI, because it rarely occurs in isolation in human subjects. Even less is known about the effects of repeated primary blast wave exposure, but existing data suggest cumulative increases in brain damage with a second blast. MRI and, in particular, diffusion tensor imaging (DTI), have become important tools for assessing bTBI in both clinical and preclinical settings. Computational statistical methods such as voxelwise analysis have shown promise in localizing and quantifying bTBI throughout the brain. In this study, we use voxelwise analysis of DTI to quantify white matter injury in a rat model of repetitive primary blast exposure. Our results show a significant increase in microstructural damage with a second blast exposure, suggesting that primary bTBI may sensitize the brain to subsequent injury. PMID:24392843

Low Velocity Impact Testing and Nondestructive Evaluation of Transparent Materials

NASA Astrophysics Data System (ADS)

Brennan, R. E.; Green, W. H.

2011-06-01

Advanced transparent materials are used in protective systems for enhancing the survivability of ground vehicles, air vehicles, and personnel in applications such as face shields, riot gear, and vehicle windows. Low velocity impact damage can limit visibility and compromise the structural integrity of a transparent system, increasing the likelihood of further damage or penetration from a high velocity impact strike. For this reason, it is critical to determine damage tolerance levels of transparent systems to indicate whether or not a component should be replaced. In this study, transparent laminate systems will be tested by comparing baseline conditions to experimentally controlled damage states. Destructive testing including air gun and sphere impact testing will be used to replicate low velocity impacts in the field. Characterization of the damaged state will include basic visual inspection as well as nondestructive techniques including cross-polarization, x-ray, and ultrasound. The combination of destructive testing and characterization of the resulting damage can help to establish a damage acceptance criterion for materials used in protective systems.

Vibration-based damage detection in a concrete beam under temperature variations using AR models and state-space approaches

NASA Astrophysics Data System (ADS)

Clément, A.; Laurens, S.

2011-07-01

The Structural Health Monitoring of civil structures subjected to ambient vibrations is very challenging. Indeed, the variations of environmental conditions and the difficulty to characterize the excitation make the damage detection a hard task. Auto-regressive (AR) models coefficients are often used as damage sensitive feature. The presented work proposes a comparison of the AR approach with a state-space feature formed by the Jacobian matrix of the dynamical process. Since the detection of damage can be formulated as a novelty detection problem, Mahalanobis distance is applied to track new points from an undamaged reference collection of feature vectors. Data from a concrete beam subjected to temperature variations and damaged by several static loading are analyzed. It is observed that the damage sensitive features are effectively sensitive to temperature variations. However, the use of the Mahalanobis distance makes possible the detection of cracking with both of them. Early damage (before cracking) is only revealed by the AR coefficients with a good sensibility.

Integrated material state awareness system with self-learning symbiotic diagnostic algorithms and models

NASA Astrophysics Data System (ADS)

Banerjee, Sourav; Liu, Lie; Liu, S. T.; Yuan, Fuh-Gwo; Beard, Shawn

2011-04-01

Materials State Awareness (MSA) goes beyond traditional NDE and SHM in its challenge to characterize the current state of material damage before the onset of macro-damage such as cracks. A highly reliable, minimally invasive system for MSA of Aerospace Structures, Naval structures as well as next generation space systems is critically needed. Development of such a system will require a reliable SHM system that can detect the onset of damage well before the flaw grows to a critical size. Therefore, it is important to develop an integrated SHM system that not only detects macroscale damages in the structures but also provides an early indication of flaw precursors and microdamages. The early warning for flaw precursors and their evolution provided by an SHM system can then be used to define remedial strategies before the structural damage leads to failure, and significantly improve the safety and reliability of the structures. Thus, in this article a preliminary concept of developing the Hybrid Distributed Sensor Network Integrated with Self-learning Symbiotic Diagnostic Algorithms and Models to accurately and reliably detect the precursors to damages that occur to the structure are discussed. Experiments conducted in a laboratory environment shows potential of the proposed technique.

Summary of floods in the United States during 1958

USGS Publications Warehouse

Hendricks, E.L.

1964-01-01

This report describes the most outstanding floods that occurred in the United States during 1958.A series of storms from January 23 to February 16 brought large amounts of precipitation to northern California and produced damaging floods, particularly in the Lower Sacramento Valley where losses totaled about \\$12 million.Major floods, notable because of the large area affected, occurred on many small streams in central and south Texas, following heavy general rains in late February. Extensive flooding occurred along the Gulf Coastal plain on the lower reaches of the major streams from the Brazos River to the Nueces River. Two lives were lost, and property damage exceeded \\$1 million.Damaging floods of April 1-7 followed one of the wettest winters in California history. Swollen streams overflowed their banks throughout the central part of the State, and discharge peaks on many streams exceeded those .of the floods of December 1955. Most severely flooded was the San Francisco Bay area. Total flood damage was estimated at \\$23 million.The storms and floods of April-May in Louisiana and adjacent States outranked all other floods in the United States during 1958 with respect to intensity of rain over a large area, number of streams having maximum discharge of record, rare occurrence of peaks, and great amount (\\$21 million) of resultant damage.Heavy rains on June 8-15 caused one of the greatest summer floods of record in central Indiana. Peak discharges were high and of rare occurrences. Failure of numerous levees along the Wabash River caused great damage. Crop damage alone was estimated at \\$48 million.Intense rains of July 1-2 caused record-breaking floods in southwestern Iowa. Rapid rises and the great magnitude of the floods on small streams resulted in 18 deaths and many injuries. Six towns and cities along the East Nishnabotna River and its tributaries were particularly hard hit; rural damage was also high. Total damage was estimated at \\$15 million.Heavy rains (as much as 40 inches during the last 2 weeks in September) from the middle of September to the middle of October caused destructive floods along the Rio Grande in Texas and Mexico. Many communities were isolated by the flood waters, and damage to crops was great.In addition to the 7 floods mentioned above, 21 others of lesser magnitude are reported in this annual summary.

Proton Damage Effects on Carbon Nanotube Field-Effect Transistors

DTIC Science & Technology

2014-06-19

PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS THESIS Evan R. Kemp, Ctr...United States. AFIT-ENP-T-14-J-39 PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS THESIS Presented to...PROTON DAMAGE EFFECTS ON CARBON NANOTUBE FIELD-EFFECT TRANSISTORS Evan R. Kemp, BS Ctr, USAF Approved: // Signed

Damage Caused by the Rogue Trustee

ERIC Educational Resources Information Center

O'Banion, Terry

2009-01-01

Fifty-nine community college presidents and chancellors in 16 states report on the damage caused by rogue trustees. While the damage to presidents, other trustees, and faculty and staff is alarming, the damage these trustees cause the college suggests that the rogue trustee may be the single most destructive force ever to plague an educational…

Methodology trends on gamma and electron radiation damage simulation studies in solids under high fluency irradiation environments

NASA Astrophysics Data System (ADS)

Cruz Inclán, Carlos M.; González Lazo, Eduardo; Rodríguez Rodríguez, Arturo; Guzmán Martínez, Fernando; Abreu Alfonso, Yamiel; Piñera Hernández, Ibrahin; Leyva Fabelo, Antonio

2017-09-01

The present work deals with the numerical simulation of gamma and electron radiation damage processes under high brightness and radiation particle fluency on regard to two new radiation induced atom displacement processes, which concern with both, the Monte Carlo Method based numerical simulation of the occurrence of atom displacement process as a result of gamma and electron interactions and transport in a solid matrix and the atom displacement threshold energies calculated by Molecular Dynamic methodologies. The two new radiation damage processes here considered in the framework of high brightness and particle fluency irradiation conditions are: 1) The radiation induced atom displacement processes due to a single primary knockout atom excitation in a defective target crystal matrix increasing its defect concentrations (vacancies, interstitials and Frenkel pairs) as a result of a severe and progressive material radiation damage and 2) The occurrence of atom displacements related to multiple primary knockout atom excitations for the same or different atomic species in an perfect target crystal matrix due to subsequent electron elastic atomic scattering in the same atomic neighborhood during a crystal lattice relaxation time. In the present work a review numeral simulation attempts of these two new radiation damage processes are presented, starting from the former developed algorithms and codes for Monte Carlo simulation of atom displacements induced by electron and gamma in

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

Gecow, Andrzej

On the way to simulating adaptive evolution of complex system describing a living object or human developed project, a fitness should be defined on node states or network external outputs. Feedbacks lead to circular attractors of these states or outputs which make it difficult to define a fitness. The main statistical effects of adaptive condition are the result of small change tendency and to appear, they only need a statistically correct size of damage initiated by evolutionary change of system. This observation allows to cut loops of feedbacks and in effect to obtain a particular statistically correct state instead ofmore » a long circular attractor which in the quenched model is expected for chaotic network with feedback. Defining fitness on such states is simple. We calculate only damaged nodes and only once. Such an algorithm is optimal for investigation of damage spreading i.e. statistical connections of structural parameters of initial change with the size of effected damage. It is a reversed-annealed method--function and states (signals) may be randomly substituted but connections are important and are preserved. The small damages important for adaptive evolution are correctly depicted in comparison to Derrida annealed approximation which expects equilibrium levels for large networks. The algorithm indicates these levels correctly. The relevant program in Pascal, which executes the algorithm for a wide range of parameters, can be obtained from the author.« less

An enhancement to the NA4 gear vibration diagnostic parameter

NASA Technical Reports Server (NTRS)

Decker, Harry J.; Handschuh, Robert F.; Zakrajsek, James J.

1994-01-01

A new vibration diagnostic parameter for health monitoring of gears, NA4*, is proposed and tested. A recently developed gear vibration diagnostic parameter NA4 outperformed other fault detection methods at indicating the start and initial progression of damage. However, in some cases, as the damage progressed, the sensitivity of the NA4 and FM4 parameters tended to decrease and no longer indicated damage. A new parameter, NA4* was developed by enhancing NA4 to improve the trending of the parameter. This allows for the indication of damage both at initiation and also as the damage progresses. The NA4* parameter was verified and compared to the NA4 and FM4 parameters using experimental data from single mesh spur and spiral bevel gear fatigue rigs. The primary failure mode for the test cases was naturally occurring tooth surface pitting. The NA4* parameter is shown to be a more robust indicator of damage.

Effect of short-term hazelnut consumption on DNA damage and oxidized LDL in children and adolescents with primary hyperlipidemia: a randomized controlled trial.

PubMed

Guaraldi, Federica; Deon, Valeria; Del Bo', Cristian; Vendrame, Stefano; Porrini, Marisa; Riso, Patrizia; Guardamagna, Ornella

2018-07-01

Children with primary hyperlipidemia are prone to develop premature atherosclerosis, possibly associated with increased oxidative stress. Nutritional therapy is the primary strategy in the treatment of hyperlipidemia and associated conditions. Dietary interventions with bioactive-rich foods, such as nuts, may contribute to the modulation of both lipid profile and the oxidative/antioxidant status. Our study aimed to assess the impact of a dietary intervention with hazelnuts on selected oxidative stress markers in children and adolescents with primary hyperlipidemia. A single-blind, 8-week, randomized, controlled, three-arm, parallel-group study was performed. Children and adolescents diagnosed with primary hyperlipidemia (n=60) received dietary guidelines and were randomized into three groups: group 1 received hazelnuts with skin (HZN+S), and group 2 hazelnuts without skin (HZN-S), at equivalent doses (15-30 g/day, based on body weight); group 3 (controls) received only dietary recommendations (no nuts). At baseline and after 8 weeks, plasma oxidized low-density lipoprotein (ox-LDL) concentrations, oxidative levels of DNA damage in PBMCs and potential correlation with changes in serum lipids were examined. A reduction of endogenous DNA damage by 18.9%±51.3% (P=.002) and 23.1%±47.9% (P=.007) was observed after HZN+S and HZN-S, respectively. Oxidatively induced DNA strand breaks decreased by 16.0%±38.2% (P=.02) following HZN+S treatment. Ox-LDL levels did not change after HZN+S intervention but positively correlated with total cholesterol and LDL cholesterol. A short-term hazelnut intervention improves cell DNA protection and resistance against oxidative stress but not ox-LDL in hyperlipidemic pediatric patients. The trial was registered at ISRCTN.com, ID no. ISRCTN12261900. Copyright © 2018 Elsevier Inc. All rights reserved.

Creep-Fatigue Damage Investigation and Modeling of Alloy 617 at High Temperatures

NASA Astrophysics Data System (ADS)

Tahir, Fraaz

The Very High Temperature Reactor (VHTR) is one of six conceptual designs proposed for Generation IV nuclear reactors. Alloy 617, a solid solution strengthened Ni-base superalloy, is currently the primary candidate material for the tubing of the Intermediate Heat Exchanger (IHX) in the VHTR design. Steady-state operation of the nuclear power plant at elevated temperatures leads to creep deformation, whereas loading transients including startup and shutdown generate fatigue. A detailed understanding of the creep-fatigue interaction in Alloy 617 is necessary before it can be considered as a material for nuclear construction in ASME Boiler and Pressure Vessel Code. Current design codes for components undergoing creep-fatigue interaction at elevated temperatures require creep-fatigue testing data covering the entire range from fatigue-dominant to creep-dominant loading. Classical strain-controlled tests, which produce stress relaxation during the hold period, show a saturation in cycle life with increasing hold periods due to the rapid stress-relaxation of Alloy 617 at high temperatures. Therefore, applying longer hold time in these tests cannot generate creep-dominated failure. In this study, uniaxial isothermal creep-fatigue tests with non-traditional loading waveforms were designed and performed at 850 and 950°C, with an objective of generating test data in the creep-dominant regime. The new loading waveforms are hybrid strain-controlled and force-controlled testing which avoid stress relaxation during the creep hold. The experimental data showed varying proportions of creep and fatigue damage, and provided evidence for the inadequacy of the widely-used time fraction rule for estimating creep damage under creep-fatigue conditions. Micro-scale damage features in failed test specimens, such as fatigue cracks and creep voids, were quantified using a Scanning Electron Microscope (SEM) to find a correlation between creep and fatigue damage. Quantitative statistical imaging analysis showed that the microstructural damage features (cracks and voids) are correlated with a new mechanical driving force parameter. The results from this image-based damage analysis were used to develop a phenomenological life-prediction methodology called the effective time fraction approach. Finally, the constitutive creep-fatigue response of the material at 950°C was modeled using a unified viscoplastic model coupled with a damage accumulation model. The simulation results were used to validate an energy-based constitutive life-prediction model, as a mechanistic model for potential component and structure level creep-fatigue analysis.

Progressive Damage Modeling of Notched Composites

NASA Technical Reports Server (NTRS)

Aitharaju, Venkat; Aashat, Satvir; Kia, Hamid; Satyanarayana, Arunkumar; Bogert, Philip

2016-01-01

There is an increased interest in using non-crimp fabric reinforced composites for primary and secondary structural weight savings in high performance automobile applications. However, one of the main challenges in implementing these composites is the lack of understanding of damage progression under a wide variety of loading conditions for general configurations. Towards that end, researchers at GM and NASA are developing new damage models to predict accurately the progressive failure of these composites. In this investigation, the developed progressive failure analysis model was applied to study damage progression in center-notched and open-hole tension specimens for various laminate schemes. The results of a detailed study with respect to the effect of element size on the analysis outcome are presented.

Earthquakes, November-December 1977

USGS Publications Warehouse

Person, W.J.

1978-01-01

In the United States, the largest earthquake during this reporting period was a magntidue 6.6 in the Andreanof Islands, which are part of the Aleutian Islands chain, on November 4 that caused some minor damage. Northern California was struck by a magnitude 4.8 earthquake on November 22 causing moderate damage in the Willits area. This was the most damaging quake in the United States during the year. Two major earthquakes of magntidues 7.0 or above to 14 for the year. 

Recovery of Ecosystem Carbon and Energy Fluxes From the 2003 Drought in Europe and the 2012 Drought in the United States

NASA Astrophysics Data System (ADS)

He, Bin; Liu, Junjie; Guo, Lanlan; Wu, Xiuchen; Xie, Xaoming; Zhang, Yafeng; Chen, Chen; Zhong, Ziqian; Chen, Ziyue

2018-05-01

Recovery of an ecosystem from drought is an important indicator of ecosystem resilience. However, few investigations have heretofore focused on the recovery of ecosystem carbon and energy fluxes but have mainly focused on the drought recovery of plant growth and ecosystem productions. Therefore, the present study uses in situ observations from FLUXNET 2015 to examine the recovery of carbon flux and energy flux of ecosystems from the 2003 European drought and the 2012 U.S. drought on the daily scale. The results reveal the strong impact of these two extreme droughts on ecosystem gross primary production, total ecosystem respiration, net ecosystem exchange, and latent heat flux. In addition, the recovery time of these indicators differ significantly. At the regional scale, the recovery of gross primary production, total ecosystem respiration, net ecosystem exchange, and latent heat flux took 44, 23, 63, and 27 days after the 2003 European drought, and the recovery for corresponding indicators for the 2012 U.S. drought took 42, 63, 15, and 33 days, respectively. Further investigations suggest that indicator background conditions and drought-damage magnitudes played an important role in regulating drought recovery in the 2003 European drought, with lower background value and greater damage leading to a longer recovery time. The ecosystem recovery from the 2012 U.S. drought, however, was dominated by the precipitation condition during the recovery period, with more precipitation associated with a shorter recovery time. These results provide crucial insight into the divergent recovery trajectories for different carbon-water processes among diverse bioclimatic regions.

Squirrel Damage to Pines

Treesearch

USDA Forest Service

1981-01-01

Flagging (dead branch tips) on jack pine and red pine may be caused by insects, diseases, or mechanical damage. In the Lake States, flagging is often the result of mechanical damage, sometimes girdling, caused when the cones are torn off by red squirrels.

A tool for the calculation of rockfall fragility curves for masonry buildings

NASA Astrophysics Data System (ADS)

Mavrouli, Olga

2017-04-01

Masonries are common structures in mountainous and coastal areas and they exhibit substantial vulnerability to rockfalls. For big rockfall events or precarious structures the damage is very high and the repair is not cost-effective. Nonetheless, for small or moderate rockfalls, the damage may vary in function of the characteristics of the impacting rock blocks and of the buildings. The evaluation of the expected damage for masonry buildings, and for different small and moderate rockfall scenarios, is useful for assessing the expected direct loss at constructed areas, and its implications for life safety. A tool for the calculation of fragility curves for masonry buildings which are impacted by rock blocks is presented. The fragility curves provide the probability of exceeding a given damage state (low, moderate and high) for increasing impact energies of the rock blocks on the walls. The damage states are defined according to a damage index equal to the percentage of the damaged area of a wall, as being proportional to the repair cost. Aleatoric and epistemic uncertainties are incorporated with respect to the (i) rock block velocity, (ii) rock block size, (iii) masonry width, and (iv) masonry resistance. The calculation of the fragility curves is applied using a Monte Carlo simulation. Given user-defined data for the average value of these four parameters and their variability, random scenarios are developed, the respective damage index is assessed for each scenario, and the probability of exceedance of each damage state is calculated. For the assessment of the damage index, a database developed by the results of 576 analytical simulations is used. The variables range is: wall width 0.4 - 1.0 m, wall tensile strength 0.1 - 0.6 MPa, rock velocity 1-20 m/s, rock size 1-20 m3. Nonetheless this tool permits the use of alternative databases, on the condition that they contain data that correlate the damage with the four aforementioned variables. The fragility curves can be calculated using this tool either for single or for groups of buildings, as long as their characteristics are properly reflected in the variability of the input parameters. Selected examples of fragility curves sets are presented demonstrating the effect of the input parameters on the calculated probability of exceeding a given damage state, for different masonry typologies (stone and brick).

Improving atomic displacement and replacement calculations with physically realistic damage models

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

Nordlund, Kai; Zinkle, Steven J.; Sand, Andrea E.

Atomic collision processes are fundamental to numerous advanced materials technologies such as electron microscopy, semiconductor processing and nuclear power generation. Extensive experimental and computer simulation studies over the past several decades provide the physical basis for understanding the atomic-scale processes occurring during primary displacement events. The current international standard for quantifying this energetic particle damage, the Norgett-Robinson-Torrens displacements per atom (NRT-dpa) model, has nowadays several well-known limitations. In particular, the number of radiation defects produced in energetic cascades in metals is only ~1/3 the NRT-dpa prediction, while the number of atoms involved in atomic mixing is about a factor ofmore » 30 larger than the dpa value. Here we propose two new complementary displacement production estimators (athermal recombination corrected dpa, arc-dpa) and atomic mixing (replacements per atom, rpa) functions that extend the NRT-dpa by providing more physically realistic descriptions of primary defect creation in materials and may become additional standard measures for radiation damage quantification.« less

Improving atomic displacement and replacement calculations with physically realistic damage models

DOE PAGES

Nordlund, Kai; Zinkle, Steven J.; Sand, Andrea E.; ...

2018-03-14

Atomic collision processes are fundamental to numerous advanced materials technologies such as electron microscopy, semiconductor processing and nuclear power generation. Extensive experimental and computer simulation studies over the past several decades provide the physical basis for understanding the atomic-scale processes occurring during primary displacement events. The current international standard for quantifying this energetic particle damage, the Norgett-Robinson-Torrens displacements per atom (NRT-dpa) model, has nowadays several well-known limitations. In particular, the number of radiation defects produced in energetic cascades in metals is only ~1/3 the NRT-dpa prediction, while the number of atoms involved in atomic mixing is about a factor ofmore » 30 larger than the dpa value. Here we propose two new complementary displacement production estimators (athermal recombination corrected dpa, arc-dpa) and atomic mixing (replacements per atom, rpa) functions that extend the NRT-dpa by providing more physically realistic descriptions of primary defect creation in materials and may become additional standard measures for radiation damage quantification.« less

Chemotherapy-induced bystander effect in response to several chloroethylnitrosoureas: an origin independent of DNA damage?

PubMed

Merle, Patrick; Morvan, Daniel; Caillaud, Denis; Demidem, Aicha

2008-01-01

Chloroethylnitrosourea (CENU) chemotherapy is used for the treatment of melanoma tumors. The main mechanism of action of this anticancer agent is via DNA damage. We recently showed in murine experiments using a parental double B16 melanoma tumor model that, after treatment of primary tumors with cystemustine (CENU agent), untreated secondary tumors exhibited growth inhibition and metabolism disorders. The response of secondary untreated tumor was called the chemotherapy-induced bystander effect. To see whether chemotherapy-induced bystander effects were induced with other members of the CENU family, we compared three CENU(s) used in melanoma treatment: cystemustine, carmustine and fotemustine. Our results demonstrate that fotemustine, like cystemustine, but not carmustine induced a protective effect against secondary untreated tumors including alterations in phospholipid derivative and glutathione which are the metabolic signature of the bystander effect. From these data we may conclude that DNA damage to the primary tumor is not sufficient to explain chemotherapy-induced bystander effects.

Improving atomic displacement and replacement calculations with physically realistic damage models.

PubMed

Nordlund, Kai; Zinkle, Steven J; Sand, Andrea E; Granberg, Fredric; Averback, Robert S; Stoller, Roger; Suzudo, Tomoaki; Malerba, Lorenzo; Banhart, Florian; Weber, William J; Willaime, Francois; Dudarev, Sergei L; Simeone, David

2018-03-14

Atomic collision processes are fundamental to numerous advanced materials technologies such as electron microscopy, semiconductor processing and nuclear power generation. Extensive experimental and computer simulation studies over the past several decades provide the physical basis for understanding the atomic-scale processes occurring during primary displacement events. The current international standard for quantifying this energetic particle damage, the Norgett-Robinson-Torrens displacements per atom (NRT-dpa) model, has nowadays several well-known limitations. In particular, the number of radiation defects produced in energetic cascades in metals is only ~1/3 the NRT-dpa prediction, while the number of atoms involved in atomic mixing is about a factor of 30 larger than the dpa value. Here we propose two new complementary displacement production estimators (athermal recombination corrected dpa, arc-dpa) and atomic mixing (replacements per atom, rpa) functions that extend the NRT-dpa by providing more physically realistic descriptions of primary defect creation in materials and may become additional standard measures for radiation damage quantification.

Mitochondrial oxidative stress in aging and healthspan

PubMed Central

2014-01-01

The free radical theory of aging proposes that reactive oxygen species (ROS)-induced accumulation of damage to cellular macromolecules is a primary driving force of aging and a major determinant of lifespan. Although this theory is one of the most popular explanations for the cause of aging, several experimental rodent models of antioxidant manipulation have failed to affect lifespan. Moreover, antioxidant supplementation clinical trials have been largely disappointing. The mitochondrial theory of aging specifies more particularly that mitochondria are both the primary sources of ROS and the primary targets of ROS damage. In addition to effects on lifespan and aging, mitochondrial ROS have been shown to play a central role in healthspan of many vital organ systems. In this article we review the evidence supporting the role of mitochondrial oxidative stress, mitochondrial damage and dysfunction in aging and healthspan, including cardiac aging, age-dependent cardiovascular diseases, skeletal muscle aging, neurodegenerative diseases, insulin resistance and diabetes as well as age-related cancers. The crosstalk of mitochondrial ROS, redox, and other cellular signaling is briefly presented. Potential therapeutic strategies to improve mitochondrial function in aging and healthspan are reviewed, with a focus on mitochondrial protective drugs, such as the mitochondrial antioxidants MitoQ, SkQ1, and the mitochondrial protective peptide SS-31. PMID:24860647

Flies, worms and the Free Radical Theory of ageing.

PubMed

Clancy, David; Birdsall, John

2013-01-01

Drosophila and Caenorhabditis elegans have provided the largest body of evidence addressing the Free Radical Theory of ageing, however the evidence has not been unequivocally supportive. Oxidative damage to DNA is probably not a major contributor, damage to lipids is assuming greater importance and damage to proteins probably the source of pathology. On balance the evidence does not support a primary role of oxidative damage in ageing in C. elegans, perhaps because of its particular energy metabolic and stress resistance profile. Evidence is more numerous, varied and consistent and hence more compelling for Drosophila, although not conclusive. However there is good evidence for a role of oxidative damage in later life pathology. Future work should: 1/ make more use of protein oxidative damage measurements; 2/ use inducible transgenic systems or pharmacotherapy to ensure genetic equivalence of controls and avoid confounding effects during development; 3/ to try to delay ageing, target interventions which reduce and/or repair protein oxidative damage. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

Deciphering neuronal population codes for acute thermal pain

NASA Astrophysics Data System (ADS)

Chen, Zhe; Zhang, Qiaosheng; Phuong Sieu Tong, Ai; Manders, Toby R.; Wang, Jing

2017-06-01

Objective. Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. Current pain research mostly focuses on molecular and synaptic changes at the spinal and peripheral levels. However, a complete understanding of pain mechanisms requires the physiological study of the neocortex. Our goal is to apply a neural decoding approach to read out the onset of acute thermal pain signals, which can be used for brain-machine interface. Approach. We used micro wire arrays to record ensemble neuronal activities from the primary somatosensory cortex (S1) and anterior cingulate cortex (ACC) in freely behaving rats. We further investigated neural codes for acute thermal pain at both single-cell and population levels. To detect the onset of acute thermal pain signals, we developed a novel latent state-space framework to decipher the sorted or unsorted S1 and ACC ensemble spike activities, which reveal information about the onset of pain signals. Main results. The state space analysis allows us to uncover a latent state process that drives the observed ensemble spike activity, and to further detect the ‘neuronal threshold’ for acute thermal pain on a single-trial basis. Our method achieved good detection performance in sensitivity and specificity. In addition, our results suggested that an optimal strategy for detecting the onset of acute thermal pain signals may be based on combined evidence from S1 and ACC population codes. Significance. Our study is the first to detect the onset of acute pain signals based on neuronal ensemble spike activity. It is important from a mechanistic viewpoint as it relates to the significance of S1 and ACC activities in the regulation of the acute pain onset.

Long-Term Empirical and Observational Evidence of Practical Helicoverpa zea Resistance to Cotton With Pyramided Bt Toxins.

PubMed

Reisig, Dominic D; Huseth, Anders S; Bacheler, Jack S; Aghaee, Mohammad-Amir; Braswell, Lewis; Burrack, Hannah J; Flanders, Kathy; Greene, Jeremy K; Herbert, D Ames; Jacobson, Alana; Paula-Moraes, Silvana V; Roberts, Phillip; Taylor, Sally V

2018-04-16

Evidence of practical resistance of Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) to Bt cotton in the United States is debatable, supported with occasional reports of boll damage in the field. Our objective was to provide both empirical and long-term observational evidence of practical resistance by linking both in-season and end-of-season measurements of H. zea damage to pyramided Bt cotton bolls and to provide Cry1Ac diet-based bioassay data in support of these damage estimates. In-season boll damage from H. zea was highly correlated to end-of-season damaged bolls. Across North Carolina, Bt cotton fields with end-of-season bolls damaged by H. zea increased during 2016 compared to previous years. Elevated damage was coupled with an increase in field sprays targeting H. zea during 2016, but not related to an increase in H. zea abundance. Bioassay data indicated that there was a range of Cry1Ac susceptibility across the southeastern United States. Given the range of susceptibility to Cry1Ac across the southeastern United States, it is probable that resistant populations are common. Since H. zea is resistant to cotton expressing pyramided Cry toxins, the adoption of new cotton varieties expressing Vip3Aa will be rapid. Efforts should be made to delay resistance of H. zea to the Vip3Aa toxin to avoid foliar insecticide use.

What Are Teachers' Opinions about Including Topics of Natural Events and Their Risks in Primary Curriculum in Kocaeli (Turkey)?

ERIC Educational Resources Information Center

Bulus Kirikkaya, Esma; Imali, Beyza

2013-01-01

Community awareness must be increased for communities to play an effective role in the mitigation of disaster damage. Education is the most effective way to accomplish this. It is important for people to know that even though they cannot intervene or prevent such events, they can take precautionary measures to reduce the damage caused by…

Evaluation of an operating MOD-OA 200 kW wind turbine blade

NASA Technical Reports Server (NTRS)

Donham, R. E.

1979-01-01

Operating loads and structural damage were monitored during operation of the MOD-OA electric generating system. The turbine was damaged locally between stations 48 and 125 after 2.8 million rotations. Loads due to degraded yaw stiffness and fretting at rib station 48 were identified as primary to this distress. The repaired blades operated an additional 4.8 million rotations without problems.

9B.08: CARDIAC AND VASCULAR DAMAGE IN PATIENTS WITH PRIMARY ALDOSTERONISM AND ESSENTIAL HYPERTENSION.

PubMed

Bertacchini, F; Paini, A; Salvetti, M; Casella, E; Rosei, C Agabiti; Colonetti, E; Donini, C; Maruelli, G; Rizzoni, D; Rosei, E Agabiti; Muiesan, M L

2015-06-01

Primary aldosteronism is a relatively common condition in hypertensive patients. Only few studies, in small groups of patients, have evaluated large arteries alterations. In some, but not in all studies, positive relationship with vascular damage was observed. To compare the prevalence of cardiac and large arteries vascular organ damage in patients with essential hypertension (EH) or primary aldosteronism (PA). In 243 consecutive patients with no interfering therapy (147 M, mean age 48 ± 11 years) a routine blood sample, including measurement of aldosterone/renin ratio (ARR) and saline load if ARR>30, was obtained. Echocardiography, carotid ultrasound and measurement of pulse wave velocity (PWV) were performed. We considered 3 groups: 48 patients with EH (ARR < 30); 122 patients with positive ARR screening but negative saline load (indeterminate aldosteronism, IA); 73 patients with PA (positive ARR and post saline aldosterone >100ng/ml)(51 % with adrenal adenoma). No differences between groups were observed in age, gender, BMI, BP values (clinic and 24 hours), glucose, lipids and renal function. LVMI was greater in PA vs both IA and EH (PA 45 ± 18, IA 39 ± 12, EH 39 ± 10 gr/m2.7, p < 0,05). Left atrial volume/BSA was significantly greater in PA vs EH (PA 27 ± 10, IA 24 ± 8, EH 23 ± 6 ml/m2, p < 0,05 for PA vs EH). A positive correlation was observed between ARR and LVMI (r = 0,20 p = 0,002), left atrium volume (r = 0,201,p < 0,001) and relative wall thickness (r = 0,394, p < 0,005). Indices of vascular damage did not differ between groups (see table). Aldosterone levels and ARR were not significantly correlated with indices of vascular damage.(Figure is included in full-text article.) : A greater prevalence of cardiac, but not of large arteries damage is observed in PA as compared to EH when a simultaneous assessment of cardiac and vascular OD is performed.

White matter damage in primary progressive aphasias: a diffusion tensor tractography study.

PubMed

Galantucci, Sebastiano; Tartaglia, Maria Carmela; Wilson, Stephen M; Henry, Maya L; Filippi, Massimo; Agosta, Federica; Dronkers, Nina F; Henry, Roland G; Ogar, Jennifer M; Miller, Bruce L; Gorno-Tempini, Maria Luisa

2011-10-01

Primary progressive aphasia is a clinical syndrome that encompasses three major phenotypes: non-fluent/agrammatic, semantic and logopenic. These clinical entities have been associated with characteristic patterns of focal grey matter atrophy in left posterior frontoinsular, anterior temporal and left temporoparietal regions, respectively. Recently, network-level dysfunction has been hypothesized but research to date has focused largely on studying grey matter damage. The aim of this study was to assess the integrity of white matter tracts in the different primary progressive aphasia subtypes. We used diffusion tensor imaging in 48 individuals: nine non-fluent, nine semantic, nine logopenic and 21 age-matched controls. Probabilistic tractography was used to identify bilateral inferior longitudinal (anterior, middle, posterior) and uncinate fasciculi (referred to as the ventral pathway); and the superior longitudinal fasciculus segmented into its frontosupramarginal, frontoangular, frontotemporal and temporoparietal components, (referred to as the dorsal pathway). We compared the tracts' mean fractional anisotropy, axial, radial and mean diffusivities for each tract in the different diagnostic categories. The most prominent white matter changes were found in the dorsal pathways in non-fluent patients, in the two ventral pathways and the temporal components of the dorsal pathways in semantic variant, and in the temporoparietal component of the dorsal bundles in logopenic patients. Each of the primary progressive aphasia variants showed different patterns of diffusion tensor metrics alterations: non-fluent patients showed the greatest changes in fractional anisotropy and radial and mean diffusivities; semantic variant patients had severe changes in all metrics; and logopenic patients had the least white matter damage, mainly involving diffusivity, with fractional anisotropy altered only in the temporoparietal component of the dorsal pathway. This study demonstrates that both careful dissection of the main language tracts and consideration of all diffusion tensor metrics are necessary to characterize the white matter changes that occur in the variants of primary progressive aphasia. These results highlight the potential value of diffusion tensor imaging as a new tool in the multimodal diagnostic evaluation of primary progressive aphasia.

Gulf Coast Disaster Management: Forest Damage Detection and Carbon Flux Estimation

NASA Astrophysics Data System (ADS)

Maki, A. E.; Childs, L. M.; Jones, J.; Matthews, C.; Spindel, D.; Batina, M.; Malik, S.; Allain, M.; Brooks, A. O.; Brozen, M.; Chappell, C.; Frey, J. W.

2008-12-01

Along the Gulf Coast and Eastern Seaboard, tropical storms and hurricanes annually cause defoliation and deforestation amongst coastal forests. After a severe storm clears, there is an urgent need to assess impacts on timber resources for targeting state and national resources to assist in recovery. It is important to identify damaged areas following the storm, due to their increased probability of fire risk, as well as the effect upon the carbon budget. Better understanding and management of the immediate and future effects on the carbon cycle in the coastal forest ecosystem is especially important. Current methods of detection involve assessment through ground-based field surveys, aerial surveys, computer modeling of meteorological data, space-borne remote sensing, and Forest Inventory and Analysis field plots. Introducing remotely-sensed data from NASA and NASA-partnered Earth Observation Systems (EOS), this project seeks to improve the current methodology and focuses on a need for methods that are more synoptic than field surveys and more closely linked to the phenomenology of tree loss and damage than passive remote sensing methods. The primary concentration is on the utilization of Ice, Cloud, and land Elevation Satellite (ICESat) Geoscience Laser Altimeter System (GLAS) data products to detect changes in forest canopy height as an indicator of post-hurricane forest disturbances. By analyzing ICESat data over areas affected by Hurricane Katrina, this study shows that ICESsat is a useful method of detecting canopy height change, though further research is needed in mixed forest areas. Other EOS utilized in this study include Landsat, Moderate Resolution Imaging Spectroradiometer (MODIS), and the NASA verified and validated international Advanced Wide Field Sensor (AWiFS) sensor. This study addresses how NASA could apply ICESat data to contribute to an improved method of detecting hurricane-caused forest damage in coastal areas; thus to pinpoint areas more susceptible to fire damage and subsequent loss of carbon sequestration.

Ability of field populations of Coptotermes spp., Reticulitermes flavipes, and Mastotermes darwiniensis (Isoptera: Rhinotermitidae; Mastotermitidae) to damage plastic cable sheathings.

PubMed

Lenz, Michael; Kard, Brad; Creffield, James W; Evans, Theodore A; Brown, Kenneth S; Freytag, Edward D; Zhong, Jun-Hong; Lee, Chow-Yang; Yeoh, Boon-Hoi; Yoshimura, Tsuyoshi; Tsunoda, Kunio; Vongkaluang, Charunee; Sornnuwat, Yupaporn; Roland, Ted A; de Santi, Marie Pommier

2013-06-01

A comparative field study was conducted to evaluate the ability of subterranean termites to damage a set of four different plastic materials (cable sheathings) exposed below- and above-ground. Eight pest species from six countries were included, viz., Coptotermes formosanus (Shiraki) in China, Japan, and the United States; Coptotermes gestroi (Wasmann) in Thailand and Malaysia; Coptotermes curvignathus (Holmgren) and Coptotermes kalshoveni (Kemner) in Malaysia; Coptotermes acinaciformis (Froggatt) with two forms of the species complex and Mastotermes darwiniensis (Froggatt) in Australia; and Reticulitermes flavipes (Kollar) in the United States. Termite species were separated into four tiers relative to decreasing ability to damage plastics. The first tier, most damaging, included C. acinaciformis, mound-building form, and M. darwiniensis, both from tropical Australia. The second tier included C. acinaciformis, tree-nesting form, from temperate Australia and C. kalshoveni from Southeast Asia. The third tier included C. curcignathus and C. gestroi from Southeast Asia and C. formosanus from China, Japan, and the United States, whereas the fourth tier included only R. flavipes, which caused no damage. A consequence of these results is that plastics considered resistant to termite damage in some locations will not be so in others because of differences in the termite fauna, for example, resistant plastics from the United States and Japan will require further testing in Southeast Asia and Australia. However, plastics considered resistant in Australia will be resistant in all other locations.

Plate-tectonic boundary formation by grain-damage and pinning

NASA Astrophysics Data System (ADS)

Bercovici, David

2015-04-01

Shear weakening in the lithosphere is an essential ingredient for understanding how and why plate tectonics is generated from mantle convection on terrestrial planets. I present continued work on a theoretical model for lithospheric shear-localization and plate generation through damage, grain evolution and Zener pinning in two-phase (polycrystalline) lithospheric rocks. Grain size evolves through the competition between coarsening, which drives grain-growth, with damage, which drives grain reduction. The interface between phases controls Zener pinning, which impedes grain growth. Damage to the interface enhances the Zener pinning effect, which then reduces grain-size, forcing the rheology into the grain-size-dependent diffusion creep regime. This process thus allows damage and rheological weakening to co-exist, providing a necessary shear-localizing feedback. Moreover, because pinning inhibits grain-growth it promotes shear-zone longevity and plate-boundary inheritance. This theory has been applied recently to the emergence of plate tectonics in the Archean by transient subduction and accumulation of plate boundaries over 1Gyr, as well as to rapid slab detachment and abrupt tectonic changes. New work explores the saturation of interface damage at low interface curvature (e.g., because it is associated with larger grains that take up more of the damage, and/or because interface area is reduced). This effect allows three possible equilibrium grain-sizes for a given stress; a small-grain-size high-shear state in diffusion creep, a large grain-size low shear state in dislocation creep, and an intermediate state (often near the deformation map phase-boundary). The low and high grain-size states are stable, while the intermediate one is unstable. This implies that a material deformed at a given stress can acquire two stable deformation regimes, a low- and high- shear state; these are indicative of plate-like flows, i.e, the coexistence of both slowly deforming plates and rapidly deforming plate boundaries.

Comparing crack damage evolution in rocks deformed under conventional and true triaxial loading

NASA Astrophysics Data System (ADS)

Browning, J.; Meredith, P. G.; Stuart, C.; Healy, D.; Harland, S. R.; Mitchell, T. M.

2017-12-01

The vast majority of experimental studies investigate damage evolution using conventional triaxial stress states (σ1 > σ2 = σ3, CTA), whereas in nature the stress state is generally truly triaxial (σ1 > σ2 > σ3, TTA). We present a comparative study of crack damage evolution during CTA vs. TTA stress conditions using results from measurements made on cubic samples of sandstone deformed in three orthogonal directions with independently controlled stress paths. We have measured, simultaneously with stress and strain, changes in wave velocities in the three principal directions, together with acoustic emission (AE) output. Changes in wave velocities are associated with both elastic closure and opening of pre-existing cracks, and the inelastic formation of new cracks. By contrast, AE is associated only with the inelastic growth of new crack damage. The onset of new damage is shown to be a function of differential stress regardless of the magnitude of mean stress. Hence, we show that damage can form due to a decrease in the minimum principal stress, which reduces mean stress but increases the differential stress. We find an approximately fivefold decrease in the number of AE events in the TTA case in comparison to the CTA case. In essence, we create two end-member crack distributions; one displaying cylindrical transverse isotropy and the other planar transverse isotropy. Taken together, the AE data, the velocities and the crack densities indicate that the intermediate principal stress plays a key role in suppressing the total amount of crack growth and concentrating it in planes sub-parallel to the minimum stress. However, the size of individual cracks remains constant. Hence, the differential stress at which rocks fail (i.e. strength) will be significantly higher under TTA stress (where σ2 > σ3) than under CTA stress (where σ2 = σ3). Cyclic loading tests show that while individual stress states are important, the stress path by which these stress states are reached is equally important. Whether the stress state has been `visited' before is key to determining and understanding damage states. Further damage commences only when the previous maximum differential stress is exceeded, regardless of whether this is achieved by increasing the maximum principal stress or by decreasing the minimum principal stress.

A probabilistic estimate of maximum acceleration in rock in the contiguous United States

USGS Publications Warehouse

Algermissen, Sylvester Theodore; Perkins, David M.

1976-01-01

This paper presents a probabilistic estimate of the maximum ground acceleration to be expected from earthquakes occurring in the contiguous United States. It is based primarily upon the historic seismic record which ranges from very incomplete before 1930 to moderately complete after 1960. Geologic data, primarily distribution of faults, have been employed only to a minor extent, because most such data have not been interpreted yet with earthquake hazard evaluation in mind.The map provides a preliminary estimate of the relative hazard in various parts of the country. The report provides a method for evaluating the relative importance of the many parameters and assumptions in hazard analysis. The map and methods of evaluation described reflect the current state of understanding and are intended to be useful for engineering purposes in reducing the effects of earthquakes on buildings and other structures.Studies are underway on improved methods for evaluating the relativ( earthquake hazard of different regions. Comments on this paper are invited to help guide future research and revisions of the accompanying map.The earthquake hazard in the United States has been estimated in a variety of ways since the initial effort by Ulrich (see Roberts and Ulrich, 1950). In general, the earlier maps provided an estimate of the severity of ground shaking or damage but the frequency of occurrence of the shaking or damage was not given. Ulrich's map showed the distribution of expected damage in terms of no damage (zone 0), minor damage (zone 1), moderate damage (zone 2), and major damage (zone 3). The zones were not defined further and the frequency of occurrence of damage was not suggested. Richter (1959) and Algermissen (1969) estimated the ground motion in terms of maximum Modified Mercalli intensity. Richter used the terms "occasional" and "frequent" to characterize intensity IX shaking and Algermissen included recurrence curves for various parts of the country in the paper accompanying his map.The first probabilistic hazard maps covering portions of the United States were by Milne and Davenport (1969a). Recently, Wiggins, Hirshberg and Bronowicki (1974) prepared a probabilistic map of maximum particle velocity and Modified Mercalli intensity for the entire United States. The maps are based on an analysis of the historical seismicity. In general, geological data were not incorporated into the development of the maps.

The chicken or the egg: mitochondrial dysfunction as a cause or consequence of toxicity in Huntington’s disease

DOE PAGES

Polyzos, Aris A.; McMurray, Cynthia T.

2016-09-12

Mitochondrial dysfunction and ensuing oxidative damage is typically thought to be a primary cause of Huntington's disease, Alzheimer's disease, and Parkinson disease. There is little doubt that mitochondria (MT) become defective as neurons die, yet whether MT defects are the primary cause or a detrimental consequence of toxicity remains unanswered. Oxygen consumption rate (OCR) and glycolysis provide sensitive and informative measures of the functional status MT and the cells metabolic regulation, yet these measures differ depending on the sample source; species, tissue type, age at measurement, and whether MT are measured in purified form or in a cell. The effectsmore » of these various parameters are difficult to quantify and not fully understood, but clearly have an impact on interpreting the bioenergetics of MT or their failure in disease states. A major goal of the review is to discuss issues and coalesce detailed information into a reference table to help in assessing mitochondrial dysfunction as a cause or consequence of Huntington's disease.« less

The chicken or the egg: mitochondrial dysfunction as a cause or consequence of toxicity in Huntington’s disease

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

Polyzos, Aris A.; McMurray, Cynthia T.

Mitochondrial dysfunction and ensuing oxidative damage is typically thought to be a primary cause of Huntington's disease, Alzheimer's disease, and Parkinson disease. There is little doubt that mitochondria (MT) become defective as neurons die, yet whether MT defects are the primary cause or a detrimental consequence of toxicity remains unanswered. Oxygen consumption rate (OCR) and glycolysis provide sensitive and informative measures of the functional status MT and the cells metabolic regulation, yet these measures differ depending on the sample source; species, tissue type, age at measurement, and whether MT are measured in purified form or in a cell. The effectsmore » of these various parameters are difficult to quantify and not fully understood, but clearly have an impact on interpreting the bioenergetics of MT or their failure in disease states. A major goal of the review is to discuss issues and coalesce detailed information into a reference table to help in assessing mitochondrial dysfunction as a cause or consequence of Huntington's disease.« less

Mechanism of unconfined dust explosions: Turbulent clustering and radiation-induced ignition.

PubMed

Liberman, Michael; Kleeorin, Nathan; Rogachevskii, Igor; Haugen, Nils Erland L

2017-05-01

It is known that unconfined dust explosions typically start off with a relatively weak primary flame followed by a severe secondary explosion. We show that clustering of dust particles in a temperature stratified turbulent flow ahead of the primary flame may give rise to a significant increase in the radiation penetration length. These particle clusters, even far ahead of the flame, are sufficiently exposed and heated by the radiation from the flame to become ignition kernels capable to ignite a large volume of fuel-air mixtures. This efficiently increases the total flame surface area and the effective combustion speed, defined as the rate of reactant consumption of a given volume. We show that this mechanism explains the high rate of combustion and overpressures required to account for the observed level of damage in unconfined dust explosions, e.g., at the 2005 Buncefield vapor-cloud explosion. The effect of the strong increase of radiation transparency due to turbulent clustering of particles goes beyond the state of the art of the application to dust explosions and has many implications in atmospheric physics and astrophysics.

Disintegration of Meatball Electrodes for LiNi x Mn y Co z O 2 Cathode Materials

DOE PAGES

Xu, R.; de Vasconcelos, L. S.; Shi, J.; ...

2017-05-12

Mechanical degradation of Li-ion batteries caused by the repetitive swelling and shrinking of electrodes upon electrochemical cycles is now well recognized. Structural disintegration of the state-of-art cathode materials of a hierarchical structure is relatively less studied. In this paper, we track the microstructural evolution of different marked regimes in LiNi x Mn y Co z O 2 (NMC) electrodes after lithiation cycles. Decohesion of primary particles constitutes the major mechanical degradation in the NMC materials, which results in the loss of connectivity of the conductive network and impedance increase. We find that the structural disintegration is largely dependent on themore » charging rate – slow charging causes more damage, and is relatively insensitive to the cyclic voltage window. We use finite element modeling to study the evolution of Li concentration and stresses in a NMC secondary particle and employ the cohesive zone model to simulate the interfacial fracture between primary particles. Finally, we reveal that microcracks accumulate and propagate during the cyclic lithiation and delithiation at a slow charging rate.« less

Fuel containment, lightning protection and damage tolerance in large composite primary aircraft structures

NASA Technical Reports Server (NTRS)

Griffin, Charles F.; James, Arthur M.

1985-01-01

The damage-tolerance characteristics of high strain-to-failure graphite fibers and toughened resins were evaluated. Test results show that conventional fuel tank sealing techniques are applicable to composite structures. Techniques were developed to prevent fuel leaks due to low-energy impact damage. For wing panels subjected to swept stroke lightning strikes, a surface protection of graphite/aluminum wire fabric and a fastener treatment proved effective in eliminating internal sparking and reducing structural damage. The technology features developed were incorporated and demonstrated in a test panel designed to meet the strength, stiffness, and damage tolerance requirements of a large commercial transport aircraft. The panel test results exceeded design requirements for all test conditions. Wing surfaces constructed with composites offer large weight savings if design allowable strains for compression can be increased from current levels.

Identifying the impact of the built environment on flood damage in Texas.

PubMed

Brody, Samuel D; Zahran, Sammy; Highfield, Wesley E; Grover, Himanshu; Vedlitz, Arnold

2008-03-01

Floods continue to pose the greatest threat to the property and safety of human communities among all natural hazards in the United States. This study examines the relationship between the built environment and flood impacts in Texas, which consistently sustains the most damage from flooding of any other state in the country. Specifically, we calculate property damage resulting from 423 flood events between 1997 and 2001 at the county level. We identify the effect of several built environment measures, including wetland alteration, impervious surface, and dams on reported property damage while controlling for biophysical and socio-economic characteristics. Statistical results suggest that naturally occurring wetlands play a particularly important role in mitigating flood damage. These findings provide guidance to planners and flood managers on how to alleviate most effectively the costly impacts of foods at the community level.

The Nature of Cold-induced Dormancy in Urediospores of Puccinia graminis tritici

PubMed Central

Maheshwari, Ramesh; Sussman, Alfred S.

1971-01-01

When air-dry urediospores of the wheat stem rust, Puccinia graminis f. sp. tritici, are exposed to temperatures below freezing, their germinability is markedly reduced, even after prolonged thawing at room temperature. Germinability is fully restored by a brief heat-shock or by vapor phase hydration. We have found that this “cold dormancy” cannot be reversed once the spores contact liquid water. Enhanced loss of metabolites occurs immediately upon suspension of cold-dormant urediospores in liquid without a prior heat-shock. Such leakage is two to three times greater than from untreated or heatshocked cold-dormant spores and accounts for up to 70% of the soluble pool of metabolites normally present in germinating urediospores. Respiratory activity of cold-dormant urediospores declines rapidly during incubation in liquid. Incorporation of isotopic carbon into cold-dormant urediospores is only a fraction of that of untreated or heat-activated spores. Thus, cold shock transforms the spores into a state of supersensitivity to liquid water, which is reversed by heat-shock or slow hydration by vapor phase equilibration. The primary cause of damage to cold-dormant cells exposed to liquid water appears to be irreversible permeability damage, followed by metabolic injury. PMID:16657610

Treatment of catastrophic antiphospholipid syndrome with defibrotide, a proposed vascular endothelial cell modulator.

PubMed

Burcoglu-O'Ral, Arsinur; Erkan, Doruk; Asherson, Ronald

2002-09-01

To define at the molecular level the vascular endothelial cell (VEC) injury characteristics of catastrophic antiphospholipid syndrome (CAPS) and to report successful therapeutic use of a VEC modulator, defibrotide. We describe a 55-year-old man with primary APS with an intractable prothrombotic state (CAPS) resistant to combined therapy with heparin, warfarin, aspirin, and dipyridamole. Treatment with defibrotide was conducted in the context of an investigational phase II protocol where the dose was regulated and individualized by disease/patient-specific molecular and clinical markers. The patient entered complete remission with defibrotide treatment. During treatment, dose dependent pharmacological actions of defibrotide and key stress markers for VEC injury were identified. Evidence of defibrotide's polypharmacology included downregulation of cytokines, notably tumor necrosis factor-alpha, as the earliest effect, cellular differentiation of VEC, possibly with direct regulatory effect over cellular genes, and the reversal of platelet consumption and prothrombotic state. Von Willebrand antigen levels were used as the sole marker to guide therapy. This case demonstrates effective remission of CAPS with defibrotide treatment. In contrast to theories that CAPS is triggered by ischemic and thrombotic tissue damage, these data present VEC injury as the primary and representative lesion of CAPS. The pathogenesis may involve concurrent impairment of different VEC functions. Achieving remission may require a polypharmacologic approach, represented here by use of defibrotide.

50 CFR 29.21-4 - Terms and conditions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... all damages to the lands or other property of the United States caused by him or by his employees, contractors, or employees of the contractors, and to indemnify the United States against any liability for damages to life, person or property arising from the occupancy or use of the lands under the easement or...

School Property Insurance: Experiences at State Level. Bulletin, 1956, No. 7

ERIC Educational Resources Information Center

Viles, N. E., Sr.

1956-01-01

School insurance programs often present major problems in school administration. School insurance of various types is one means of preventing or limiting financial loss from property damage or the claims of individuals for injury or damage payments. In varying degrees the States have delegated to certain local administrative school units and/or…

Non-destructive evaluation of laboratory scale hydraulic fracturing using acoustic emission

NASA Astrophysics Data System (ADS)

Hampton, Jesse Clay

The primary objective of this research is to develop techniques to characterize hydraulic fractures and fracturing processes using acoustic emission monitoring based on laboratory scale hydraulic fracturing experiments. Individual microcrack AE source characterization is performed to understand the failure mechanisms associated with small failures along pre-existing discontinuities and grain boundaries. Individual microcrack analysis methods include moment tensor inversion techniques to elucidate the mode of failure, crack slip and crack normal direction vectors, and relative volumetric deformation of an individual microcrack. Differentiation between individual microcrack analysis and AE cloud based techniques is studied in efforts to refine discrete fracture network (DFN) creation and regional damage quantification of densely fractured media. Regional damage estimations from combinations of individual microcrack analyses and AE cloud density plotting are used to investigate the usefulness of weighting cloud based AE analysis techniques with microcrack source data. Two granite types were used in several sample configurations including multi-block systems. Laboratory hydraulic fracturing was performed with sample sizes ranging from 15 x 15 x 25 cm3 to 30 x 30 x 25 cm 3 in both unconfined and true-triaxially confined stress states using different types of materials. Hydraulic fracture testing in rock block systems containing a large natural fracture was investigated in terms of AE response throughout fracture interactions. Investigations of differing scale analyses showed the usefulness of individual microcrack characterization as well as DFN and cloud based techniques. Individual microcrack characterization weighting cloud based techniques correlated well with post-test damage evaluations.

Economic analysis of the proposed rule to prevent arrival of new genetic strains of the rust fungus Puccinia psidii in Hawai'i.

USGS Publications Warehouse

Burnett, Kimberly; D'Evelyn, Sean; Loope, Lloyd; Wada, Christopher A.

2012-01-01

Since its first documented introduction to Hawai‘i in 2005, the rust fungus P. psidii has already severely damaged Syzygium jambos (Indian rose apple) trees and the federally endangered Eugenia koolauensis (nioi). Fortunately, the particular strain has yet to cause serious damage to ‘ōhi‘a, which comprises roughly 80% of the state’s native forests and covers 400,000 ha. Although the rust has affected less than 5% of Hawaii’s ‘ōhi‘a trees thus far, the introduction of more virulent strains and the genetic evolution of the current strain are still possible. Since the primary pathway of introduction is Myrtaceae plant material imported from outside the state, potential damage to ‘ohi‘a can be minimized by regulating those high-risk imports. We discuss the economic impact on the state’s florist, nursery, landscaping, and forest plantation industries of a proposed rule that would ban the import of non-seed Myrtaceae plant material and require a one-year quarantine of seeds. Our analysis suggests that the benefits to the forest plantation industry of a complete ban on non-seed material would likely outweigh the costs to other affected sectors, even without considering the reduction in risk to ‘ōhi‘a. Incorporating the value of ‘ōhi‘a protection would further increase the benefit-cost ratio in favor of an import ban.

Damage sources for the NIF Grating Debris Shield (GDS) and methods for their mitigation

NASA Astrophysics Data System (ADS)

Carr, C. W.; Bude, J.; Miller, P. E.; Parham, T.; Whitman, P.; Monticelli, M.; Raman, R.; Cross, D.; Welday, B.; Ravizza, F.; Suratwala, T.; Davis, J.; Fischer, M.; Hawley, R.; Lee, H.; Matthews, M.; Norton, M.; Nostrand, M.; Vanblarcom, D.; Sommer, S.

2017-11-01

The primary sources of damage on the National Ignition Facility (NIF) Grating Debris Shield (GDS) are attributed to two independent types of laser-induced particulates. The first comes from the eruptions of bulk damage in a disposable debris shield downstream of the GDS. The second particle source comes from stray light focusing on absorbing glass armor at higher than expected fluences. We show that the composition of the particles is secondary to the energetics of their delivery, such that particles from either source are essentially benign if they arrive at the GDS with low temperatures and velocities.

Low-damage high-throughput grazing-angle sputter deposition on graphene

NASA Astrophysics Data System (ADS)

Chen, C.-T.; Casu, E. A.; Gajek, M.; Raoux, S.

2013-07-01

Despite the prevalence of sputter deposition in the microelectronics industry, it has seen very limited applications for graphene electronics. In this letter, we report systematic investigation of the sputtering induced damages in graphene and identify the energetic sputtering gas neutrals as the primary cause of graphene disorder. We further demonstrate a grazing-incidence sputtering configuration that strongly suppresses fast neutral bombardment and retains graphene structure integrity, creating considerably lower damage than electron-beam evaporation. Such sputtering technique yields fully covered, smooth thin dielectric films, highlighting its potential for contact metals, gate oxides, and tunnel barriers fabrication in graphene device applications.

Understanding radiation damage on sub-cellular scale using RADAMOL simulation tool

NASA Astrophysics Data System (ADS)

Štěpán, Václav; Davídková, Marie

2016-11-01

We present an overview of the biophysical model RADAMOL developed as a Monte Carlo simulation tool for physical, physico-chemical and chemical stages of ionizing radiation action. Direct and indirect radiation damage by 10 keV electrons, and protons and alpha particles with energies from 1 MeV up to 30 MeV to a free DNA oligomer or DNA in the complex with lac repressor protein is analyzed. The role of radiation type and energy, oxygen concentration and DNA interaction with proteins on yields and distributions of primary biomolecular damage is demonstrated and discussed.

Evaluation of damage in reinforced concrete bridge beams using acoustic emission technique

NASA Astrophysics Data System (ADS)

Vidya Sagar, R.; Raghu Prasad, B. K.; Sharma, Reema

2012-06-01

Acoustic emission (AE) testing is a well-known method for damage identification of various concrete structures including bridges. This article presents a method to assess damage in reinforced concrete (RC) bridge beams subjected to incremental cyclic loading. The specifications in the standard NDIS-2421 were used to classify the damage in RC bridge beams. Earlier researchers classified the damage occurring in bridge beams by using crack mouth opening displacement (CMOD) and AE released and proposed a standard (NDIS-2421: the Japanese Society for NonDestructive Inspection). In general, multiple cracks take place in RC beams under bending; therefore, utilisation of CMOD for crack detection may not be appropriate. In the present study, the damage in RC beams is classified by using the AE released, deflection, strains in steel and concrete, because the measurement of the strains in steel and concrete is easy and the codes of practice are specified for different limit states (IS-456:2000). The observations made in the present experimental study have some important practical applications in assessing the state of damage of concrete structural members.

Applications of Earth Remote Sensing for Identifying Tornado and Severe Weather Damage

NASA Technical Reports Server (NTRS)

Schultz, Lori; Molthan, Andrew; Burks, Jason E.; Bell, Jordan; McGrath, Kevin; Cole, Tony

2016-01-01

NASA SPoRT (Short-term Prediction Research and Transition Center) provided MODIS (Moderate Resolution Imaging Spectrometer) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery to WFOs (Weather Forecast Offices) in Alabama to support April 27th, 2011 damage assessments across the state. SPoRT was awarded a NASA Applied Science: Disasters Feasibility award to investigate the applicability of including remote sensing imagery and derived products into the NOAA/NWS (National Oceanic and Atmospheric Administration/National Weather System) Damage Assessment Toolkit (DAT). Proposal team was awarded the 3-year proposal to implement a web mapping service and associate data feeds from the USGS (U.S. Geological Survey) to provide satellite imagery and derived products directly to the NWS thru the DAT. In the United States, NOAA/NWS is charged with performing damage assessments when storm or tornado damage is suspected after a severe weather event. This has led to the development of the Damage Assessment Toolkit (DAT), an application for smartphones, tablets and web browsers that allows for the collection, geo-location, and aggregation of various damage indicators collected during storm surveys.

Modeling extreme hurricane damage in the United States using generalized Pareto distribution

NASA Astrophysics Data System (ADS)

Dey, Asim Kumer

Extreme value distributions are used to understand and model natural calamities, man made catastrophes and financial collapses. Extreme value theory has been developed to study the frequency of such events and to construct a predictive model so that one can attempt to forecast the frequency of a disaster and the amount of damage from such a disaster. In this study, hurricane damages in the United States from 1900-2012 have been studied. The aim of the paper is three-fold. First, normalizing hurricane damage and fitting an appropriate model for the normalized damage data. Secondly, predicting the maximum economic damage from a hurricane in future by using the concept of return period. Finally, quantifying the uncertainty in the inference of extreme return levels of hurricane losses by using a simulated hurricane series, generated by bootstrap sampling. Normalized hurricane damage data are found to follow a generalized Pareto distribution. tion. It is demonstrated that standard deviation and coecient of variation increase with the return period which indicates an increase in uncertainty with model extrapolation.

Evaluations of plastic mesh tubes for protecting conifer seedling from pocket gophers in three western states

USGS Publications Warehouse

Engeman, Richard M.; Anthony, Richard M.; Barnes, Victor G.; Krupa, Heather W.; Evans, James

1999-01-01

The efficacy of plastic mesh tubes for protecting conifer seedlings from pocket gopher damage was evaluated on three national forest lands in three states. In each area, cohorts of 640 protected seedlings and 640 unprotected seedlings (3,840 total) were individually monitored for damage, survival, and growth twice each summer for 5 yr after planting. Substantial differences were found between protected and unprotected seedlings for time until occurrence of damage, survival time, proportion damaged and proportion surviving, as well as differences in growth. Over the three forest study sites, the proportion of unprotected seedlings damaged ranged from 60-89%, whereas the proportion of protected seedlings damaged after 5 yr ranged from 18-27%. The proportion of unprotected seedlings that died of gopher damage over 5 yr ranged from 46-64%, versus 1-19% for protected seedlings. Height growth was 25% greater for protected seedlings. Even when only undamaged seedlings were considered, protected seedlings exhibited superior height growth, possibly due to a more favorable microclimate provided by the tubes. These results were reflected in the higher and more uniform stocking rates for protected seedlings.

26 CFR 301.7426-2 - Recovery of damages in certain cases.

Code of Federal Regulations, 2010 CFR

2010-04-01

... in the case of negligence), or the sum of— (1) Actual, direct economic damages as defined in § 301... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Recovery of damages in certain cases. 301.7426... the United States § 301.7426-2 Recovery of damages in certain cases. (a) In general. In addition to...

Herbivory and climate interact serially to control monoterpene emissions from pinyon pine forests.

PubMed

Trowbridge, Amy M; Daly, Ryan W; Helmig, Detlev; Stoy, Paul C; Monson, Russell K

2014-06-01

The emission of volatile monoterpenes from coniferous trees impacts the oxidative state of the troposphere and multi-trophic signaling between plants and animals. Previous laboratory studies have revealed that climate anomalies and herbivory alter the rate of tree monoterpene emissions. However, no studies to date have been conducted to test these relations in situ. We conducted a two-year field experiment at two semiarid sites dominated by pinyon pine (Pinus edulis) during outbreaks of a specialist herbivore, the southwestern tiger moth (Lophocampa ingens: Arctiidae). We discovered that during the early spring, when herbivory rates were highest, monoterpene emission rates were approximately two to six times higher from undamaged needles on damaged trees, with this increase in emissions due to alpha-pinene, beta-pinene, and camphene at both sites. During mid-summer, emission rates did not differ between previously damaged and undamaged trees at the site on the Western Slope of the Rocky Mountains, but rather tracked changes in the temperature and precipitation regime characteristic of the region. As the mid-summer drought progressed at the Eastern Slope site, emission rates were low, but differences between previously damaged and undamaged trees were not statistically significant. Despite no difference in emissions, mid-summer tissue monoterpene concentrations were significantly lower in previously damaged trees at both sites. With the onset of monsoon rains during late summer, emission rates from previously damaged trees increased to levels higher than those of undamaged trees despite the lack of herbivory. We conclude that (1) herbivory systemically increases the flux of terpenes to the atmosphere during the spring, (2) drought overrides the effect of past herbivory as the primary control over emissions during the mid-summer, and (3) a release from drought and the onset of late-summer rains is correlated with a secondary increase in emissions, particularly from herbivore-damaged trees, possibly due to a drought-delayed stimulation of induced monoterpene synthesis and/or increases in stomatal conductance. A greater understanding of the interactive effects of seasonality and herbivory on monoterpene emissions provides much needed information regarding the atmospheric and ecological consequences that these compounds will have for semiarid ecosystems.

Proposal as to Efficient Collection and Exploitation of Earthquake Damage Information and Verification by Field Experiment at Toyohashi City

NASA Astrophysics Data System (ADS)

Zama, Shinsaku; Endo, Makoto; Takanashi, Ken'ichi; Araiba, Kiminori; Sekizawa, Ai; Hosokawa, Masafumi; Jeong, Byeong-Pyo; Hisada, Yoshiaki; Murakami, Masahiro

Based on the earlier study result that the gathering of damage information can be quickly achieved in a municipality with a smaller population, it is proposed that damage information is gathered and analyzed using an area roughly equivalent to a primary school district as a basic unit. The introduction of this type of decentralized system is expected to quickly gather important information on each area. The information gathered by these communal disaster prevention bases is sent to the disaster prevention headquarters which in turn feeds back more extensive information over a wider area to the communal disaster prevention bases. Concrete systems have been developed according to the above mentioned framework, and we performed large-scale experiments on simulating disaster information collection, transmission and on utilization for smooth responses against earthquake disaster with collaboration from Toyohashi City, Aichi Prefecture, where is considered to suffer extensive damage from the Tokai and Tonankai Earthquakes with very high probability of the occurrence. Using disaster information collection/transmission equipments composed of long-distance wireless LAN, a notebook computer, a Web camera and an IP telephone, city staffs could easily input and transmit the information such as fire, collapsed houses and impassable roads, which were collected by the inhabitants participated in the experiment. Headquarters could confirm such information on the map automatically plotted, and also state of each disaster-prevention facility by means of Web-cameras and IP telephones. Based on the damage information, fire-spreading, evaluation, and traffic simulations were automatically executed at the disaster countermeasure office and their results were displayed on the large screen to utilize for making decisions such as residents' evacuation. These simulated results were simultaneously displayed at each disaster-prevention facility and were served to make people understand the situation of whole damage of the city and necessity of evacuation with optimum timing and access. According to the evaluation by the city staffs through the experiments, information technology is available for rationally implementing initial responses just after a large earthquake in spite of some improvement on the systems used in the experiments.

Numerical analysis of static strength for different damages of hydraulic structures when changing stressed and strained state

NASA Astrophysics Data System (ADS)

Volosukhin, V. A.; Bandurin, M. A.; Vanzha, V. V.; Mikheev, A. V.; Volosukhin, Y. V.

2018-05-01

The results of finite element state simulation of stressed and strained changes under different damages of hydraulic structures are presented. As a result of the experiment, a solidstate model of bearing elements was built. Stressed and strained state of reinforced concrete bearing elements under different load combinations is considered. Intensive threshold of danger to form longitudinal cracks and defects in reinforced concrete elements is determined.

Evidence, Rhetoric and Collateral Damage: The Problematic Pursuit of "World Class" Standards

ERIC Educational Resources Information Center

Alexander, Robin

2011-01-01

Drawing initially on evidence assembled by the Cambridge Primary Review, and acknowledging Maurice Galton's trenchant critiques of recent educational policy, this paper tracks the rise and decline of the flagship standards agenda which was launched by the Blair government in 1997 and came to dominate the work of England's primary schools during…

Effect of microstructural damage on ply stresses in laminated composites

NASA Technical Reports Server (NTRS)

Allen, D. H.; Nottorf, E. W.; Harris, C. E.

1988-01-01

The mechanisms involved in damage and failure of laminated orthotropic composites are investigated theoretically. The continuum model developed accounts for both matrix cracks and interply delamination using second-order tensor-valued internal-state variables based on the locally averaged microcrack dynamics. The derivation of the model is given in detail, and numerical results for sample problems are presented in extensive graphs and tables. The model is shown to be effective in predicting stresses at the ply level, and significant damage-induced decreases in laminate stress states are found.

Hypogonadotrophism fails to prevent severe testicular damage induced by total body irradiation in a patient with beta-thalassaemia major and acute lymphoblastic leukaemia.

PubMed

Chatterjee, R; Kottaridis, P D; McGarrigle, H H; Papatryphonos, A; Goldstone, A H

2001-11-01

Radiation and chemotherapeutic drugs for cancer produce prolonged and often irreversible gonadal damage. To determine whether total body irradiation (TBI)-induced gonadal damage can be prevented by suppression of pituitary gonadotrophin levels, we studied a patient with transfusion dependent homozygous beta-thalassaemia and acute lymphoblastic leukaemia (ALL) who underwent one-antigen mismatched related bone marrow transplantation (BMT). Our data showed that despite having hypogonadotrophic hypogonadism (HH) prior to BMT, the patient developed primary testicular failure following the procedure, indicating that hypogonadotrophism failed to offer protection against TBI-induced testicular damage in this patient. Although this is an interesting case report, no firm conclusions can be drawn from a single patient.

Changing rooster sperm membranes to facilitate cryopreservation

USDA-ARS?s Scientific Manuscript database

Cryopreservation damages rooster sperm membranes. Part of this damage is due to membrane transitioning from the fluid to the gel state as temperature is reduced. This damage may be prevented by increasing membrane fluidity at low temperatures by incorporating cholesterol or unsaturated lipids into t...

Recent Advances in Composite Damage Mechanics

NASA Technical Reports Server (NTRS)

Reifsnider, Ken; Case, Scott; Iyengar, Nirmal

1996-01-01

The state of the art and recent developments in the field of composite material damage mechanics are reviewed, with emphasis on damage accumulation. The kinetics of damage accumulation are considered with emphasis on the general accumulation of discrete local damage events such as single or multiple fiber fractures or microcrack formation. The issues addressed include: how to define strength in the presence of widely distributed damage, and how to combine mechanical representations in order to predict the damage tolerance and life of engineering components. It is shown that a damage mechanics approach can be related to the thermodynamics of the damage accumulation processes in composite laminates subjected to mechanical loading and environmental conditions over long periods of time.

Management of colonic injuries in the combat theater.

PubMed

Cho, S David; Kiraly, Laszlo N; Flaherty, Stephen F; Herzig, Daniel O; Lu, Kim C; Schreiber, Martin A

2010-05-01

Combat injuries are more often associated with blast, penetrating, and high-energy mechanisms than civilian trauma, generating controversy about the management of combat colonic injury. Despite implementation of mandatory colostomy in World War II, recent civilian data suggest that primary repair without diversion is safe and feasible. This study describes the modern management of battle-related colonic injuries and seeks to determine whether management strategy affects early complications. Records from the combat theater (downrange) and tertiary referral center in Germany were retrospectively reviewed from 2005 to 2006. Patient characteristics, management strategy, treatment course, and early complications were recorded. Comparison groups by management strategy were as follows: primary repair, diversion, and damage control. A total of 133 (97% male) patients sustained colonic injuries from penetrating (71%), blunt (5%), and blast (23%) mechanisms. Average injury severity score was 21 and length of stay in the referral center was 7.1 days. Injury distribution was 21% ascending, 21% descending, 15% transverse, 27% sigmoid, and 25% rectum. Downrange complications for primary repair, initial ostomy, and damage control groups were 14%, 15%, and 30%, respectively. On discharge from the center, 62% of patients had undergone a diversion. The complication rate was 18% overall and was unrelated to management strategy (P = .16). Multivariate analysis did not identify independent predictors of complications. Early complications were similar by mechanism, anatomic location, severity of injury, and management strategy. More diversions were performed for rectosigmoid injury. Good surgical judgment allows for low morbidity and supports primary repair in selected cases. Damage control surgery is effective in a multinational theater of operations.

Performance Versus Safety of Some Primary and Rechargeable Lithium Batteries

DTIC Science & Technology

2004-12-01

which can ignite during abuse. At the same time, manganese dioxide is an oxidising agent and it decomposes at 535oC, giving off oxygen, thus...is endothermic for nicad but exothermic for nickel- metal hydride. Therefore, nickel-metal hydride cells are more prone to damage from...With nail penetration, Figure 6. Photograph showing damage inflicted onto a lithium-ion gel-polymer cell by several hammer blows

Time Domain Reflectometry for Damage Detection of Laminated CFRP plate

DTIC Science & Technology

2011-08-18

Final Report PROJECT ID: AOARD-10-4112 Title: Time Domain Reflectometry for damage detection of laminated CFRP plate Researcher: Professor Akira...From July/2010 To July/2011 Abstract Recently, high toughness Carbon Fiber Reinforced Polymer (CFRP) laminates are used to primary structures. The...large laminated CFRP structures. In the previous study, Time Domain Reflectometry (TDR) method is adopted for the detection of the fiber breakages of

Influence of anoxia on the induction of mutations by phenylalanine radicals during gamma-irradiation of plasmid DNA in aqueous solution.

PubMed

Kuipers, Gitta K; Slotman, Ben J; Reitsma-Wijker, Carola A; van Andel, Rob J; Poldervaart, Hester A; Lafleur, M Vincent M

2004-12-21

When DNA is irradiated in aqueous solution, most of the damage is inflicted by water-derived radicals. This is called the indirect effect of ionizing radiation. However in whole cells not only the primary formed water radicals play a role, because some cellular compounds form secondary radicals which can also damage DNA. It is known that the amino acid phenylalanine is able to react with water radicals, resulting in the production of secondary phenylalanine radicals which can damage and inactivate DNA. In a previous study the influence of the presence of phenylalanine during gamma-irradiation of DNA in aqueous solution under oxic conditions was studied. Under anoxic irradiation conditions different amounts and types of reactive water-derived radicals are formed compared to oxic conditions and also different phenylalanine radicals are formed. Therefore, this study examines the influence of the presence of phenylalanine under anoxic conditions on the gamma-radiation-induced mutation spectrum. The results indicate that phenylalanine radicals are damaging to DNA, but less effective compared to primary water radicals. On the mutational level, in the presence of phenylalanine radicals under anoxic conditions, the amount of mutations on G:C base pairs was significantly decreased as compared to oxic conditions. Furthermore, the results of this study indicate that nucleotide excision repair is involved in repair of both inactivating and mutagenic damage induced by phenylalanine radicals under anoxic conditions.

Differential dpa calculations with SPECTRA-PKA

NASA Astrophysics Data System (ADS)

Gilbert, M. R.; Sublet, J.-Ch.

2018-06-01

The processing code SPECTRA-PKA produces energy spectra of primary atomic recoil events (or primary knock-on atoms, PKAs) for any material composition exposed to an irradiation spectrum. Such evaluations are vital inputs for simulations aimed at understanding the evolution of damage in irradiated material, which is generated in cascade displacement events initiated by PKAs. These PKA spectra present the full complexity of the input (to SPECTRA-PKA) nuclear data-library evaluations of recoil events. However, the commonly used displacements per atom (dpa) measure, which is an integral measure over all possible recoil events of the displacement damage dose, is still widely used and has many useful applications - as both a comparative and correlative quantity. This paper describes the methodology employed that allows the SPECTRA-PKA code to evaluate dpa rates using the energy-dependent recoil (PKA) cross section data used for the PKA distributions. This avoids the need for integral displacement kerma cross sections and also provides new insight into the relative importance of different reaction channels (and associated different daughter residual and emitted particles) to the total integrated dpa damage dose. Results are presented for Fe, Ni, W, and SS316. Fusion dpa rates are compared to those in fission, highlighting the increased contribution to damage creation in the former from high-energy threshold reactions.

DNA damage in hemodialysis patients with chronic kidney disease; a test of the role of diabetes mellitus; a comet assay investigation.

PubMed

Mamur, Sevcan; Unal, Fatma; Altok, Kadriye; Deger, Serpil Muge; Yuzbasioglu, Deniz

2016-04-01

The incidence of chronic kidney disease (CKD) is increasing rapidly. Diabetes mellitus (DM) is the most important cause of CKD. We studied the possible role of DM in CKD patients with respect to DNA damage, as assessed by the comet assay in 60 CKD patients (with or without DM) undergoing hemodialysis and in 26 controls. Effects of other factors, such as age, sex, hypertension, duration of hemodialysis, body mass index (BMI), and levels of hemoglobin (HB), intact parathormone (iPTH), and ferritin (FER), were also examined. Primary DNA damage measured by the comet assay was significantly higher in CKD patients than in controls. Among CKD patients, the following correlations were observed. (1) There was no difference in comet tail length or tail intensity between diabetic and non-diabetic individuals. (2) Age, sex, hemoglobin, hypertension, duration of hemodialysis, and ferritin levels affected neither tail length nor intensity. (3) BMI values above 25kg/m(2) and iPTH levels above 300pg/ml were associated with significantly greater comet tail length. Our results indicate that primary DNA damage is increased in CKD patients undergoing hemodialysis, compared to controls; however, DM had no additional effect. Copyright © 2016. Published by Elsevier B.V.

DISPLACEMENT CASCADE SIMULATION IN TUNGSTEN AT 1025 K

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

Setyawan, Wahyu; Nandipati, Giridhar; Roche, Kenneth J.

2013-09-30

Molecular dynamics simulation was employed to investigate the irradiation damage properties of bulk tungsten at 1025 K (0.25 melting temperature). A comprehensive data set of primary cascade damage was generated up to primary knock-on atom (PKA) energies 100 keV. The dependence of the number of surviving Frenkel pairs (NFP) on the PKA energy (E) exhibits three different characteristic domains presumably related to the different cascade morphologies that form. The low-energy regime < 0.2 keV is characterized by a hit-or-miss type of Frenkel pair (FP) production near the displacement threshold energy of 128 eV. The middle regime 0.3 – 30 keVmore » exhibits a sublinear dependence of log(NFP) vs log(E) associated with compact cascade morphology with a slope of 0.73. Above 30 keV, the cascade morphology consists of complex branches or interconnected damage regions. In this extended morphology, large interstitial clusters form from superposition of interstitials from nearby damage regions. Strong clustering above 30 keV results in a superlinear dependence of log(NFP) vs log(E) with a slope of 1.365. At 100 keV, an interstitial cluster of size 92 and a vacancy cluster of size 114 were observed.« less

Using Satellite Remote Sensing to Assist the National Weather Service (NWS) in Storm Damage Surveys

NASA Technical Reports Server (NTRS)

Schultz, Lori A.; Molthan, Andrew; McGrath, Kevin; Bell, Jordan; Cole, Tony; Burks, Jason

2016-01-01

In the United States, the National Oceanic and Atmospheric Administration (NOAA) National Weather Service (NWS) is charged with performing damage assessments when storm or tornado damage is suspected after a severe weather event. This has led to the development of the Damage Assessment Toolkit (DAT), an application for smartphones, tablets and web browsers that allows for the collection, geolocation, and aggregation of various damage indicators collected during storm surveys.

Damage pattern as a function of radiation quality and other factors.

PubMed

Burkart, W; Jung, T; Frasch, G

1999-01-01

An understanding of damage pattern in critical cellular structures such as DNA is an important prerequisite for a mechanistic assessment of primary radiation damage, its possible repair, and the propagation of residual changes in somatic and germ cells as potential contributors to disease or ageing. Important quantitative insights have been made recently on the distribution in time and space of critical lesions from direct and indirect action of ionizing radiation on mammalian cells. When compared to damage from chemicals or from spontaneous degradation, e.g. depurination or base deamination in DNA, the potential of even low-LET radiation to create local hot spots of damage from single particle tracks is of utmost importance. This has important repercussions on inferences from critical biological effects at high dose and dose rate exposure situations to health risks at chronic, low-level exposures as experienced in environmental and controlled occupational settings. About 10,000 DNA lesions per human cell nucleus and day from spontaneous degradation and chemical attack cause no apparent effect, but a dose of 4 Gy translating into a similar number of direct and indirect DNA breaks induces acute lethality. Therefore, single lesions cannot explain the high efficiency of ionizing radiation in the induction of mutation, transformation and loss of proliferative capacity. Clustered damage leading to poorly repairable double-strand breaks or even more complex local DNA degradation, correlates better with fixed damage and critical biological endpoints. A comparison with other physical, chemical and biological agents indicates that ionizing radiation is indeed set apart from these by its unique micro- and nano-dosimetric traits. Only a few other agents such as bleomycin have a similar potential to cause complex damage from single events. However, in view of the multi-stage mechanism of carcinogenesis, it is still an open question whether dose-effect linearity for complex primary DNA damage and resulting fixed critical cellular lesions translate into linearity for radiation-induced cancer. To solve this enigma, a quantitative assessment of all genotoxic and harmful non-genotoxic agents affecting the human body would be needed.

7 CFR 51.317 - Damage.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.317 Damage. “Damage... appearance, or the edible or shipping quality of the apple. In addition, specific defect measurements are based on an apple three inches in diameter. Corresponding smaller or larger areas would be allowed on...

7 CFR 51.317 - Damage.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., CERTIFICATION, AND STANDARDS) United States Standards for Grades of Apples Definitions § 51.317 Damage. “Damage... appearance, or the edible or shipping quality of the apple. In addition, specific defect measurements are based on an apple three inches in diameter. Corresponding smaller or larger areas would be allowed on...

78 FR 42755 - Proposed Information Collection; Comment Request; Natural Resource Damage Assessment Restoration...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-17

... Collection; Comment Request; Natural Resource Damage Assessment Restoration Project Information Sheet AGENCY... collection. The purpose of this information collection is to assist state and federal Natural Resource Trustees in more efficiently carrying out the restoration planning phase of Natural Resource Damage...

7 CFR 51.3064 - Damage.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., CERTIFICATION, AND STANDARDS) United States Standards for Florida Avocados Definitions § 51.3064 Damage. Damage... inch in width, or when healed and the appearance is materially affected; (b) Pulled stems when the exposed stem cavity is excessively deep, or when skin surrounding the stem cavity is more than slightly...

7 CFR 51.3064 - Damage.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., CERTIFICATION, AND STANDARDS) United States Standards for Florida Avocados Definitions § 51.3064 Damage. Damage... inch in width, or when healed and the appearance is materially affected; (b) Pulled stems when the exposed stem cavity is excessively deep, or when skin surrounding the stem cavity is more than slightly...

Red-cockaded woodpecker cavity-tree damage by Hurricane Rita: an evaluation of contributing factors

Treesearch

Ben Bainbridge; Kristen A. Baum; Daniel Saenz; Cory K. Adams

2011-01-01

Picoides borealis (Red-cockaded Woodpecker) is an endangered species inhabiting pine savannas of the southeastern United States. Because the intensity of hurricanes striking the southeastern United States is likely to increase as global temperatures rise, it is important to identify factors contributing to hurricane damage to Red-cockaded Woodpecker cavity-trees. Our...

43 CFR 9239.0-8 - Measure of damage.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.0-8 Measure of damage... other trespass in accordance with the decision of the Supreme Court of the United States in the case of... by the laws of the State in which the trespass is committed, unless by Federal law a different rule...

43 CFR 9239.0-8 - Measure of damage.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.0-8 Measure of damage... other trespass in accordance with the decision of the Supreme Court of the United States in the case of... by the laws of the State in which the trespass is committed, unless by Federal law a different rule...

43 CFR 9239.0-8 - Measure of damage.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.0-8 Measure of damage... other trespass in accordance with the decision of the Supreme Court of the United States in the case of... by the laws of the State in which the trespass is committed, unless by Federal law a different rule...

43 CFR 9239.0-8 - Measure of damage.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.0-8 Measure of damage... other trespass in accordance with the decision of the Supreme Court of the United States in the case of... by the laws of the State in which the trespass is committed, unless by Federal law a different rule...

The predominant protective effect of tianeptine over other antidepressants in models of neuronal apoptosis: the effect blocked by inhibitors of MAPK/ERK1/2 and PI3-K/Akt pathways.

PubMed

Jantas, D; Krawczyk, S; Lason, W

2014-02-01

Tianeptine (Tian) possesses neuroprotective potential, however, little is known about the effect of this drug in models of neuronal apoptosis. In the present study, we aimed (1) to compare the neuroprotective capacities of some antidepressants (ADs) in the models of staurosporine (St)- and doxorubicin (Dox)-evoked cell death, activating the intracellular and the extracellular apoptotic pathway, respectively; (2) to identify the Tian-modulated steps underlying its neuroprotective action; (3) to test the effect of various ADs against Dox-evoked cell damage in glia cells. Primary neuronal and glia cell cultures and retinoic acid-differentiated human neuroblastoma SH-SY5Y (RA-SH-SY5Y) cells were co-treated with imipramine, fluoxetine, citalopram, reboxetine, mirtazapine or Tian and St or Dox. The data showed the predominant neuroprotective effect of Tian over other tested ADs against St- and Dox-induced cell damage in primary neurons and in RA-SH-SY5Y cells. This effect was shown to be caspase-3-independent but connected with attenuation of DNA fragmentation. Moreover, neuroprotection elicited by Tian was blocked by pharmacological inhibitors of MAPK/ERK1/2 and PI3-K/Akt signaling pathways as well by inhibitor of necroptosis, necrostatin-1. Interestingly, the protective effects of all tested ADs were demonstrated in primary glia cells against the Dox-evoked cell damage. The obtained data suggests the glial cells as a common target for protective action of various ADs whereas in relation to neuronal cells only Tian possesses such properties, at least against St- and Dox-induced cell damage. Moreover, this neuroprotective effect of Tian is caspase-3-independent and engages the regulation of survival pathways (MAPK/ERK1/2 and PI3-K/Akt).

Cell cycle perturbations and genotoxic effects in human primary fibroblasts induced by low-energy protons and X/gamma-rays.

PubMed

Antoccia, Antonio; Sgura, Antonella; Berardinelli, Francesco; Cavinato, Maria; Cherubini, Roberto; Gerardi, Silvia; Tanzarella, Caterina

2009-09-01

The effect of graded doses of high-linear energy transfer (LET) low-energy protons to induce cycle perturbations and genotoxic damage was investigated in normal human fibroblasts. Furthermore, such effects were compared with those produced by low-LET radiations. HFFF2, human primary fibroblasts were exposed to either protons (LET = 28.5 keV/microm) or X/gamma-rays, and endpoints related to cell cycle kinetics and DNA damage analysed. Following both type of irradiations, unsynchronized cells suffered an inhibition to entry into S-phase for doses of 1-4 Gy and remained arrested in the G(1)-phase for several days. The levels of induction of regulator proteins, such as TP53 and CDKN1A showed a clear LET-dependence. DSB induction and repair as measured by scoring for gamma-H2AX foci indicated that protons, with respect to X-rays, yielded a lower number of DSBs per Gy, which showed a slower kinetics of disappearance. Such result was in agreement with the extent of MN induction in binucleated cells after X-irradiation. No significant differences between the two types of radiations were observed with the clonogenic assay, resulting anyway the slope of gamma-ray curve higher than that the proton one. In conclusion, in normal human primary fibroblasts cell cycle arrest at the G(1)/S transition can be triggered shortly after irradiation and maintained for several hours post-irradiation of both protons and X-rays. DNA damage produced by protons appears less amenable to be repaired and could be transformed in cytogenetic damage in the form of MN.

The effects of strawberry tree water leaf extract, arbutin and hydroquinone on haematological parameters and levels of primary DNA damage in white blood cells of rats.

PubMed

Jurica, Karlo; Brčić Karačonji, Irena; Kopjar, Nevenka; Shek-Vugrovečki, Ana; Cikač, Tihana; Benković, Vesna

2018-04-06

Strawberry tree (Arbutus unedo L., Ericaceae) leaves represent a potent source of biologically active compounds and have been used for a long to relieve symptoms of various health impairments and diseases. Two major compounds related to their beneficial activities in animals and humans are arbutin and hydroquinone. To establish potential benefit/risk ratio associated with daily oral administration of strawberry tree water leaf extract, arbutin and hydroquinone in doses expected to be non-toxic. We performed a 14-day and a 28-day study on male and female Lewis rats and evaluated main haematological parameters and the effects of treatments on the levels of primary DNA damage in white blood cells (WBC) using the alkaline comet assay. Our findings suggest no significant changes in the haematological parameters following prolonged exposure to strawberry tree water leaf extract, arbutin, and hydroquinone. However, hydroquinone causes increased, and extract as well as arbutin decreased WBC count in male rats compared to control after 14 days of treatment. DNA damage measured in WBC of rats treated with all compounds was below 10% of the DNA in the comet tail, which indicates low genotoxicity. The genotoxic potential of strawberry water leaf extract was within acceptable limits and reflected effects of a complex chemical composition upon DNA. We also observed slight gender- and exposure time- related differences in primary DNA damage in the leucocytes of control and treated rats. Future studies should investigate which doses of strawberry tree water leaf extract would be most promising for the potential use as a substitute for bearberry leaves for treatment of urinary infection. Copyright © 2017 Elsevier B.V. All rights reserved.

Atomistic simulations of focused ion beam machining of strained silicon

NASA Astrophysics Data System (ADS)

Guénolé, J.; Prakash, A.; Bitzek, E.

2017-09-01

The focused ion beam (FIB) technique has established itself as an indispensable tool in the material science community, both to analyze samples and to prepare specimens by FIB milling. In combination with digital image correlation (DIC), FIB milling can, furthermore, be used to evaluate intrinsic stresses by monitoring the strain release during milling. The irradiation damage introduced by such milling, however, results in a change in the stress/strain state and elastic properties of the material; changes in the strain state in turn affect the bonding strength, and are hence expected to implicitly influence irradiation damage formation and sputtering. To elucidate this complex interplay between strain, irradiation damage and sputtering, we perform TRIM calculations and molecular dynamics simulations on silicon irradiated by Ga+ ions, with slab and trench-like geometries, whilst simultaneously applying uniaxial tensile and compressive strains up to 4%. In addition we calculate the threshold displacement energy (TDE) and the surface binding energy (SBE) for various strain states. The sputter rate and amount of damage produced in the MD simulations show a clear influence of the strain state. The SBE shows no significant dependence on strain, but is strongly affected by surface reconstructions. The TDE shows a clear strain-dependence, which, however, cannot explain the influence of strain on the extent of the induced irradiation damage or the sputter rate.

Development and evaluation of an ozone deposition scheme for coupling to a terrestrial biosphere model

NASA Astrophysics Data System (ADS)

Franz, Martina; Simpson, David; Arneth, Almut; Zaehle, Sönke

2017-01-01

Ozone (O3) is a toxic air pollutant that can damage plant leaves and substantially affect the plant's gross primary production (GPP) and health. Realistic estimates of the effects of tropospheric anthropogenic O3 on GPP are thus potentially important to assess the strength of the terrestrial biosphere as a carbon sink. To better understand the impact of ozone damage on the terrestrial carbon cycle, we developed a module to estimate O3 uptake and damage of plants for a state-of-the-art global terrestrial biosphere model called OCN. Our approach accounts for ozone damage by calculating (a) O3 transport from 45 m height to leaf level, (b) O3 flux into the leaf, and (c) ozone damage of photosynthesis as a function of the accumulated O3 uptake over the lifetime of a leaf. A comparison of modelled canopy conductance, GPP, and latent heat to FLUXNET data across European forest and grassland sites shows a general good performance of OCN including ozone damage. This comparison provides a good baseline on top of which ozone damage can be evaluated. In comparison to literature values, we demonstrate that the new model version produces realistic O3 surface resistances, O3 deposition velocities, and stomatal to total O3 flux ratios. A sensitivity study reveals that key metrics of the air-to-leaf O3 transport and O3 deposition, in particular the stomatal O3 uptake, are reasonably robust against uncertainty in the underlying parameterisation of the deposition scheme. Nevertheless, correctly estimating canopy conductance plays a pivotal role in the estimate of cumulative O3 uptake. We further find that accounting for stomatal and non-stomatal uptake processes substantially affects simulated plant O3 uptake and accumulation, because aerodynamic resistance and non-stomatal O3 destruction reduce the predicted leaf-level O3 concentrations. Ozone impacts on GPP and transpiration in a Europe-wide simulation indicate that tropospheric O3 impacts the regional carbon and water cycling less than expected from previous studies. This study presents a first step towards the integration of atmospheric chemistry and ecosystem dynamics modelling, which would allow for assessing the wider feedbacks between vegetation ozone uptake and tropospheric ozone burden.

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

Huang, J. Y.; E, J. C.; Huang, J. W.

Impact fracture of single-crystal Si is critical to long-term reliability of electronic devices and solar cells for its wide use as components or substrates in semiconductor industry. Single-crystal Si is loaded along two different crystallographic directions with a split Hopkinson pressure bar integrated with an in situ x-ray imaging and diffraction system. Bulk stress histories are measured, simultaneously with x-ray phase contrast imaging (XPCI) and Laue diffraction. Damage evolution is quantified with grayscale maps from XPCI. Single-crystal Si exhibits pronounced anisotropy in fracture modes, and thus fracture strengths and damage evolution. For loading along [11¯ 0] and viewing along [001],more » (1¯1¯0)[11¯ 0] cleavage is activated and induces horizontal primary cracks followed by perpendicular wing cracks. However, for loading along [011¯] and viewing along [111], random nucleation and growth of shear and tensile-splitting crack networks lead to catastrophic failure of materials with no cleavage. The primary-wing crack mode leads to a lower characteristic fracture strength due to predamage, but a more concentrated strength distribution, i.e., a higher Weibull modulus, compared to the second loading case. Furthermore, the sequential primary cracking, wing cracking and wing-crack coalescence processes result in a gradual increase of damage with time, deviating from theoretical predictions. Particle size and aspect ratios of fragments are discussed with postmortem fragment analysis, which verifies fracture modes observed in XPCI.« less

ATM-deficiency increases genomic instability and metastatic potential in a mouse model of pancreatic cancer.

PubMed

Drosos, Yiannis; Escobar, David; Chiang, Ming-Yi; Roys, Kathryn; Valentine, Virginia; Valentine, Marc B; Rehg, Jerold E; Sahai, Vaibhav; Begley, Lesa A; Ye, Jianming; Paul, Leena; McKinnon, Peter J; Sosa-Pineda, Beatriz

2017-09-11

Germline mutations in ATM (encoding the DNA-damage signaling kinase, ataxia-telangiectasia-mutated) increase Familial Pancreatic Cancer (FPC) susceptibility, and ATM somatic mutations have been identified in resected human pancreatic tumors. Here we investigated how Atm contributes to pancreatic cancer by deleting this gene in a murine model of the disease expressing oncogenic Kras (Kras G12D ). We show that partial or total ATM deficiency cooperates with Kras G12D to promote highly metastatic pancreatic cancer. We also reveal that ATM is activated in pancreatic precancerous lesions in the context of DNA damage and cell proliferation, and demonstrate that ATM deficiency leads to persistent DNA damage in both precancerous lesions and primary tumors. Using low passage cultures from primary tumors and liver metastases we show that ATM loss accelerates Kras-induced carcinogenesis without conferring a specific phenotype to pancreatic tumors or changing the status of the tumor suppressors p53, p16 Ink4a and p19 Arf . However, ATM deficiency markedly increases the proportion of chromosomal alterations in pancreatic primary tumors and liver metastases. More importantly, ATM deficiency also renders murine pancreatic tumors highly sensitive to radiation. These and other findings in our study conclusively establish that ATM activity poses a major barrier to oncogenic transformation in the pancreas via maintaining genomic stability.

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

Hanson, Andrew D.; Henry, Christopher S.; Fiehn, Oliver

It is increasingly clear that (a) many metabolites undergo spontaneous or enzyme-catalyzed side reactions in vivo, (b) the damaged metabolites formed by these reactions can be harmful, and (c) organisms have biochemical systems that limit the buildup of damaged metabolites. These damage-control systems either return a damaged molecule to its pristine state (metabolite repair) or convert harmful molecules to harmless ones (damage preemption). Because all organisms share a core set of metabolites that suffer the same chemical and enzymatic damage reactions, certain damage-control systems are widely conserved across the kingdoms of life. Relatively few damage reactions and damage-control systems aremore » well known. Uncovering new damage reactions and identifying the corresponding damaged metabolites, damage-control genes, and enzymes demands a coordinated mix of chemistry, metabolomics, cheminformatics, biochemistry, and comparative genomics. This review illustrates the above points using examples from plants, which are at least as prone to metabolite damage as other organisms.« less

BILLBOARD EXPRESSING LOCAL HUMOR CONCERNING FLOOD DAMAGE TO WALNUT STREET ...

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

BILLBOARD EXPRESSING LOCAL HUMOR CONCERNING FLOOD DAMAGE TO WALNUT STREET BRIDGE, I-83 SOUTHBOUND, LOOKING WEST. BILLBOARD EXPRESSING LOCAL HUMOR CONCERNING FLOOD DAMAGE TO WALNUT STREET BRIDGE, I-83 SOUTHBOUND, LOOKING WEST. - Walnut Street Bridge, Spanning Susquehanna River at Walnut Street (State Route 3034), Harrisburg, Dauphin County, PA

44 CFR 206.252 - Insurance requirements for facilities damaged by flood.

Code of Federal Regulations, 2011 CFR

2011-10-01

... facilities damaged by flood. 206.252 Section 206.252 Emergency Management and Assistance FEDERAL EMERGENCY... Assistance Insurance Requirements § 206.252 Insurance requirements for facilities damaged by flood. (a) Where... insurance policy. (b) The reduction stated above shall not apply to a PNP facility which could not be...

22 CFR 21.1 - Policy.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Department of State may settle or compromise a personal damages claim against an employee by the payment of available funds at any time, provided the alleged conduct giving rise to the personal damages claim was... request either to agree to indemnify or to settle a personal damages claim before entry of an adverse...

22 CFR 21.1 - Policy.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Department of State may settle or compromise a personal damages claim against an employee by the payment of available funds at any time, provided the alleged conduct giving rise to the personal damages claim was... request either to agree to indemnify or to settle a personal damages claim before entry of an adverse...

Detection of damaged DNA bases by DNA glycosylase enzymes.

PubMed

Friedman, Joshua I; Stivers, James T

2010-06-22

A fundamental and shared process in all forms of life is the use of DNA glycosylase enzymes to excise rare damaged bases from genomic DNA. Without such enzymes, the highly ordered primary sequences of genes would rapidly deteriorate. Recent structural and biophysical studies are beginning to reveal a fascinating multistep mechanism for damaged base detection that begins with short-range sliding of the glycosylase along the DNA chain in a distinct conformation we call the search complex (SC). Sliding is frequently punctuated by the formation of a transient "interrogation" complex (IC) where the enzyme extrahelically inspects both normal and damaged bases in an exosite pocket that is distant from the active site. When normal bases are presented in the exosite, the IC rapidly collapses back to the SC, while a damaged base will efficiently partition forward into the active site to form the catalytically competent excision complex (EC). Here we review the unique problems associated with enzymatic detection of rare damaged DNA bases in the genome and emphasize how each complex must have specific dynamic properties that are tuned to optimize the rate and efficiency of damage site location.

Damage resistant optics for a mega-joule solid-state laser

NASA Astrophysics Data System (ADS)

Campbell, J. H.; Rainer, F.; Kozlowski, M. R.; Wolfe, C. R.; Thomas, I.; Milanovich, F.

1990-12-01

Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence, LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3+ phosphate glass) Nova laser to a 1.5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically, the damage threshold of Nd(+3)-doped phosphate laser glass, multilayer dielectric coatings, and non-linear optical crystals (e.g., KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1.5 to 2 MJ Nd(+3)-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed; threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented.

Damage resistant optics for a megajoule solid state laser

NASA Astrophysics Data System (ADS)

Campbell, Jack H.; Rainer, Frank; Kozlowski, Mark R.; Wolfe, C. Robert; Thomas, Ian M.; Milanovich, Fred P.

1991-06-01

Research on Inertial Confinement Fusion (ICF) has progressed rapidly in the past several years. As a consequence LLNL is developing plans to upgrade the current 120 kJ solid state (Nd3-phosphate glass) Nova laser to a 1 . 5 to 2 megajoule system with the goal of achieving fusion ignition. The design of the planned Nova Upgrade is briefly discussed. Because of recent improvements in the damage resistance of optical materials it is now technically and economically feasible to build a megajoule-class solid state laser. Specifically the damage threshold of Nd3- doped phosphate laser glass muliilayer dielectric coatings and non-linear optical crystals (e. g. KDP) have been dramatically improved. These materials now meet the fluence requirements for a 1. 5-2 MJ Nd3-glass laser operating at 1054 and 351 nm and at a pulse length of 3 ns. The recent improvements in damage thresholds are reviewed threshold data at both 1064 and 355 nm and the measured pulse length scaling are presented. 1.

The Air Quality and Economic Impact of Atmospheric Lead from General Aviation Aircraft in the United States

NASA Astrophysics Data System (ADS)

Wolfe, P. J.; Selin, N. E.; Barrett, S. R. H.

2015-12-01

While leaded fuels for automobiles were phased-out of use in the United States by 1996, lead (Pb) continues to be used as an anti-knock additive for piston-driven aircraft. We model the annual concentration of atmospheric lead attributable to piston driven aircraft emissions in the continental United States using the Community Multi-scale Air Quality (CMAQ) model. Using aircraft emissions inventories for 2008, we then calculate annual economic damages from lead as lifetime employment losses for a one-year cohort exposed to elevated atmospheric lead concentrations using a range of concentration response functions from literature. Mean and median estimates of annual damages attributable to lifetime lost earnings are 1.06 and 0.60 billion respectively. Economy-wide impacts of IQ-deficits on productivity and labor increase expected damages by 54%. Damages are sensitive to background lead concentrations; as emissions decrease from other sources, the damages attributable to aviation are expected to increase holding aviation emissions constant. The monetary impact of General Aviation lead emissions on the environment is the same order of magnitude as noise, climate change, and air quality degradation from all commercial operations.

Structural damage identification using damping: a compendium of uses and features

NASA Astrophysics Data System (ADS)

Cao, M. S.; Sha, G. G.; Gao, Y. F.; Ostachowicz, W.

2017-04-01

The vibration responses of structures under controlled or ambient excitation can be used to detect structural damage by correlating changes in structural dynamic properties extracted from responses with damage. Typical dynamic properties refer to modal parameters: natural frequencies, mode shapes, and damping. Among these parameters, natural frequencies and mode shapes have been investigated extensively for their use in damage characterization by associating damage with reduction in local stiffness of structures. In contrast, the use of damping as a dynamic property to represent structural damage has not been comprehensively elucidated, primarily due to the complexities of damping measurement and analysis. With advances in measurement technologies and analysis tools, the use of damping to identify damage is becoming a focus of increasing attention in the damage detection community. Recently, a number of studies have demonstrated that damping has greater sensitivity for characterizing damage than natural frequencies and mode shapes in various applications, but damping-based damage identification is still a research direction ‘in progress’ and is not yet well resolved. This situation calls for an overall survey of the state-of-the-art and the state-of-the-practice of using damping to detect structural damage. To this end, this study aims to provide a comprehensive survey of uses and features of applying damping in structural damage detection. First, we present various methods for damping estimation in different domains including the time domain, the frequency domain, and the time-frequency domain. Second, we investigate the features and applications of damping-based damage detection methods on the basis of two predominant infrastructure elements, reinforced concrete structures and fiber-reinforced composites. Third, we clarify the influential factors that can impair the capability of damping to characterize damage. Finally, we recommend future research directions for advancing damping-based damage detection. This work holds the promise of (a) helping researchers identify crucial components in damping-based damage detection theories, methods, and technologies, and (b) leading practitioners to better implement damping-based structural damage identification.

Central Motor Conduction Studies and Diagnostic Magnetic Resonance Imaging in Children with Severe Primary and Secondary Dystonia

ERIC Educational Resources Information Center

McClelland, Verity; Mills, Kerry; Siddiqui, Ata; Selway, Richard; Lin, Jean-Pierre

2011-01-01

Aim: Dystonia in childhood has many causes. Imaging may suggest corticospinal tract dysfunction with or without coexistent basal ganglia damage. There are very few published neurophysiological studies on children with dystonia; one previous study has focused on primary dystonia. We investigated central motor conduction in 62 children (34 males, 28…

Resin transfer molding for advanced composite primary wing and fuselage structures

NASA Technical Reports Server (NTRS)

Markus, Alan

1992-01-01

The stitching and resin transfer molding (RTM) processes developed at Douglas Aircraft Co. are successfully demonstrating significant cost reductions with good damage tolerance properties. These attributes were identified as critical to application of advanced composite materials to commercial aircraft primary structures. The RTM/stitching developments, cost analyses, and test results are discussed of the NASA Advanced Composites Technology program.

Polyethylene Damage Increases With Varus Implant Alignment in Posterior-stabilized and Constrained Condylar Knee Arthroplasty.

PubMed

Li, Zhichang; Esposito, Christina I; Koch, Chelsea N; Lee, Yuo-Yu; Padgett, Douglas E; Wright, Timothy M

2017-12-01

Implant malalignment in primary TKA has been reported to increase stresses placed on the bearing surfaces of implant components. We used a longitudinally maintained registry coupled with an implant retrieval program to consider whether preoperative, postoperative, or prerevision malalignment was associated with increased risk of revision surgery after TKA. (1) What is the relative polyethylene damage on medial and lateral compartments of the tibial plateaus from revised TKAs? (2) Does coronal TKA alignment affect implant performance, such that TKAs aligned in varus are predisposed to experience increased polyethylene damage? (3) Does TKA alignment differ between postoperative and prerevision radiographs, and if so, what does this difference suggest about the mechanical contact load placed on a knee with a TKA? Between 2007 and 2012, we performed 18,065 primary TKAs at our institution. By March 2016, 178 of those TKAs (1%) were revised at our center at least 2 years after primary surgery at our institution. Eighteen of those TKAs were excluded from this analysis because the tibial insert was not explanted during revision surgery, and four more were excluded because the inserts were lost or returned to the patient before the study was initiated, leaving 156 retrieved polyethylene tibial inserts (in 153 patients) revised at greater than 2 years after the primary TKA for this retrospective study. Patients who underwent revision surgery elsewhere were not considered here, since this study depended on having retrieved components. Polyethylene damage modes of burnishing, pitting, scratching, delamination, surface deformation, abrasion, and third-body debris were subjectively graded on a scale of 0 to 3 to reflect the extent and severity of each damage mode. On preoperative, postoperative, and prerevision radiographs, overall alignment, femoral alignment, and tibial alignment in the coronal plane were measured according to the protocol recommended by the Knee Society. Knees with more overall varus alignment after TKA had increased total damage on the retrieved tibial inserts (Spearman's rank correlation coefficients of -0.3 [95% CI, -0.4 to -0.1; p = 0.001]). We also found revised TKAs tended to drift back into greater varus before revision surgery, with a mean (SD) of 3.6° ± 4.0° valgus for postoperative alignment compared with 1.7° ± 6.4° prerevision (p = 0.04). Despite surgical efforts to achieve neutral mechanical alignment, remaining varus alignment places an increased contact load on the polyethylene articular surfaces. The drift toward further varus alignment postoperatively is consistent with the knee adduction moment remaining high after surgery. While we found a predisposition toward recurrence of the preoperative varus deformity, we did not find increased medial as opposed to lateral polyethylene damage, which may be explained by the curve-on-curve toroidal design of the articulating surfaces of the TKA implants in this study.

Linking Grain Boundary Microstructure to Stress Corrosion Cracking of Cold Rolled Alloy 690 in PWR Primary Water

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

Bruemmer, Stephen M.; Olszta, Matthew J.; Toloczko, Mychailo B.

2012-10-01

Grain boundary microstructures and microchemistries are examined in cold-rolled alloy 690 tubing and plate materials and comparisons are made to intergranular stress corrosion cracking (IGSCC) behavior in PWR primary water. Chromium carbide precipitation is found to be a key aspect for materials in both the mill annealed and thermally treated conditions. Cold rolling to high levels of reduction was discovered to produce small IG voids and cracked carbides in alloys with a high density of grain boundary carbides. The degree of permanent grain boundary damage from cold rolling was found to depend directly on the initial IG carbide distribution. Formore » the same degree of cold rolling, alloys with few IG precipitates exhibited much less permanent damage. Although this difference in grain boundary damage appears to correlate with measured SCC growth rates, crack tip examinations reveal that cracked carbides appeared to blunt propagation of IGSCC cracks in many cases. Preliminary results suggest that the localized grain boundary strains and stresses produced during cold rolling promote IGSCC susceptibility and not the cracked carbides and voids.« less

Response of Lemna minor L. to short-term cobalt exposure: The effect on photosynthetic electron transport chain and induction of oxidative damage.

PubMed

Begović, Lidija; Mlinarić, Selma; Antunović Dunić, Jasenka; Katanić, Zorana; Lončarić, Zdenko; Lepeduš, Hrvoje; Cesar, Vera

2016-06-01

The effect of two concentrations of cobalt (Co(2+)) on photosynthetic activity and antioxidative response in Lemna minor L. were assessed 24, 48 and 72h after the start of the exposure. Higher concentration of cobalt (1mM) induced growth inhibition while lower concentration (0.01mM) increased photosynthetic pigments content. Analysis of chlorophyll a fluorescence transients revealed high sensitivity of photosystem II primary photochemistry to excess of Co(2+) especially at the higher concentration where decreased electron transport beyond primary quinone acceptor QA(-) and impaired function of oxygen evolving complex (OEC) was observed. Due to impairment of OEC, oxygen production was decreased at higher Co(2+) concentration. Activity of superoxide dismutase was mainly inhibited while lipid peroxidation increased, at both concentrations, indicating that cobalt-induced oxidative damage after short exposure and moreover, susceptibility of the membranes in the cell to cobalt toxicity. Results obtained in this study suggest possible application of used parameters as tools in assessment of early damage caused by metals. Copyright © 2016 Elsevier B.V. All rights reserved.

Southern pine beetle in loblolly pine: simulating within stand interactions using the process model SPBLOBTHIN

Treesearch

Brian Strom; J. R. Meeker; J. Bishir; James Roberds; X. Wan

2016-01-01

Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are...

Morbidity of Early Spine Surgery in the Multiply Injured Patient

DTIC Science & Technology

2014-07-31

stable’’) based on the following clinical criteria, which were adopted from previously described criteria to indicate a damage control approach to...obtained from primary source documents. Presence of any intra- cranial injury or a chest injury was identified by review of the trauma computed tomography...approach to their injuries [7, 19–21]. ‘‘Damage Control surgery’’ was first adopted by trauma surgeons to describe initial control of penetrating

Recent changes in flood damage in the United States from observations and ACME model

NASA Astrophysics Data System (ADS)

Leng, G.; Leung, L. R.

2017-12-01

Despite efforts to mitigate flood hazards in flood-prone areas, survey- and report-based flood databases show that flood damage has increased and emerged as one of the most costly disaster in the United States since the 1990s. Understanding the mechanism driving the changes in flood damage is therefore critical for reducing flood risk. In this study, we first conduct a comprehensive analysis of the changing characteristics of flood damage at local, state and country level. Results show a significant increasing trend in the number of flood hazards, causing economic losses of up to $7 billion per year. The ratio of flood events that caused tangible economical cost to the total flood events has exhibited a non-significant increasing trend before 2007 followed by a significant decrease, indicating a changing vulnerability to floods. Analysis also reveals distinct spatial and temporal patterns in the threshold intensity of flood hazards with tangible economical cost. To understand the mechanism behind the increasing flood damage, we develop a flood damage economic model coupled with the integrated hydrological modeling system of ACME that features a river routing model with an inundation parameterization and a water use and regulation model. The model is evaluated over the country against historical records. Several numerical experiments are then designed to explore the mechanisms behind the recent changes in flood damage from the perspective of flood hazard, exposure and vulnerability, which constitute flood damage. The role of human activities such as reservoir operations and water use in modifying regional floods are also explored using the new tool, with the goal of improving understanding and modeling of vulnerability to flood hazards.

Polyphosphate is a key factor for cell survival after DNA damage in eukaryotic cells.

PubMed

Bru, Samuel; Samper-Martín, Bàrbara; Quandt, Eva; Hernández-Ortega, Sara; Martínez-Laínez, Joan M; Garí, Eloi; Rafel, Marta; Torres-Torronteras, Javier; Martí, Ramón; Ribeiro, Mariana P C; Jiménez, Javier; Clotet, Josep

2017-09-01

Cells require extra amounts of dNTPs to repair DNA after damage. Polyphosphate (polyP) is an evolutionary conserved linear polymer of up to several hundred inorganic phosphate (Pi) residues that is involved in many functions, including Pi storage. In the present article, we report on findings demonstrating that polyP functions as a source of Pi when required to sustain the dNTP increment essential for DNA repair after damage. We show that mutant yeast cells without polyP produce less dNTPs upon DNA damage and that their survival is compromised. In contrast, when polyP levels are ectopically increased, yeast cells become more resistant to DNA damage. More importantly, we show that when polyP is reduced in HEK293 mammalian cell line cells and in human dermal primary fibroblasts (HDFa), these cells become more sensitive to DNA damage, suggesting that the protective role of polyP against DNA damage is evolutionary conserved. In conclusion, we present polyP as a molecule involved in resistance to DNA damage and suggest that polyP may be a putative target for new approaches in cancer treatment or prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of basal DNA damage and oxidative stress in Wistar rat leukocytes after exposure to microwave radiation.

PubMed

Garaj-Vrhovac, Vera; Gajski, Goran; Trosić, Ivancica; Pavicić, Ivan

2009-05-17

The aim of this study was to assess whether microwave-induced DNA damage is basal or it is also generated through reactive oxygen species (ROS) formation. After having irradiated Wistar rats with 915MHz microwave radiation, we assessed different DNA alterations in peripheral leukocytes using standard and formamidopyrimidine DNA-glycosylase (Fpg)-modified comet assay. The first is a sensitive tool for detecting primary DNA damage, and the second is much more specific for detecting oxidative damage. The animals were irradiated for 1h a day for 2 weeks at a field power density of 2.4W/m(2), and the whole-body average specific absorption rate (SAR) of 0.6W/kg. Both the standard and the Fpg-modified comet assay detected increased DNA damage in blood leukocytes of the exposed rats. The significant increase in Fpg-detected DNA damage in the exposed rats suggests that oxidative stress is likely to be responsible. DNA damage detected by the standard comet assay indicates that some other mechanisms may also be involved. In addition, both methods served proved sensitive enough to measure basal and oxidative DNA damage after long-term exposure to 915MHz microwave radiation in vivo.

A study to compute integrated dpa for neutron and ion irradiation environments using SRIM-2013

NASA Astrophysics Data System (ADS)

Saha, Uttiyoarnab; Devan, K.; Ganesan, S.

2018-05-01

Displacements per atom (dpa), estimated based on the standard Norgett-Robinson-Torrens (NRT) model, is used for assessing radiation damage effects in fast reactor materials. A computer code CRaD has been indigenously developed towards establishing the infrastructure to perform improved radiation damage studies in Indian fast reactors. We propose a method for computing multigroup neutron NRT dpa cross sections based on SRIM-2013 simulations. In this method, for each neutron group, the recoil or primary knock-on atom (PKA) spectrum and its average energy are first estimated with CRaD code from ENDF/B-VII.1. This average PKA energy forms the input for SRIM simulation, wherein the recoil atom is taken as the incoming ion on the target. The NRT-dpa cross section of iron computed with "Quick" Kinchin-Pease (K-P) option of SRIM-2013 is found to agree within 10% with the standard NRT-dpa values, if damage energy from SRIM simulation is used. SRIM-2013 NRT-dpa cross sections applied to estimate the integrated dpa for Fe, Cr and Ni are in good agreement with established computer codes and data. A similar study carried out for polyatomic material, SiC, shows encouraging results. In this case, it is observed that the NRT approach with average lattice displacement energy of 25 eV coupled with the damage energies from the K-P option of SRIM-2013 gives reliable displacement cross sections and integrated dpa for various reactor spectra. The source term of neutron damage can be equivalently determined in the units of dpa by simulating self-ion bombardment. This shows that the information of primary recoils obtained from CRaD can be reliably applied to estimate the integrated dpa and damage assessment studies in accelerator-based self-ion irradiation experiments of structural materials. This study would help to advance the investigation of possible correlations between the damages induced by ions and reactor neutrons.

Obesity in aging exacerbates blood-brain barrier disruption, neuroinflammation, and oxidative stress in the mouse hippocampus: effects on expression of genes involved in beta-amyloid generation and Alzheimer's disease.

PubMed

Tucsek, Zsuzsanna; Toth, Peter; Sosnowska, Danuta; Gautam, Tripti; Mitschelen, Matthew; Koller, Akos; Szalai, Gabor; Sonntag, William E; Ungvari, Zoltan; Csiszar, Anna

2014-10-01

There is growing evidence that obesity has deleterious effects on the brain and cognitive function in the elderly population. However, the specific mechanisms through which aging and obesity interact to promote cognitive decline remain unclear. To test the hypothesis that aging exacerbates obesity-induced cerebromicrovascular damage and neuroinflammation, we compared young (7 months) and aged (24 months) high fat diet-fed obese C57BL/6 mice. Aging exacerbated obesity-induced systemic inflammation and blood-brain barrier disruption, as indicated by the increased circulating levels of proinflammatory cytokines and increased presence of extravasated immunoglobulin G in the hippocampus, respectively. Obesity-induced blood-brain barrier damage was associated with microglia activation, upregulation of activating Fc-gamma receptors and proinflammatory cytokines, and increased oxidative stress. Treatment of cultured primary microglia with sera derived from aged obese mice resulted in significantly more pronounced microglia activation and oxidative stress, as compared with treatment with young sera. Serum-induced activation and oxidative stress were also exacerbated in primary microglia derived from aged animals. Hippocampal expression of genes involved in regulation of the cellular amyloid precursor protein-dependent signaling pathways, beta-amyloid generation, and the pathogenesis of tauopathy were largely unaffected by obesity in aged mice. Collectively, obesity in aging is associated with a heightened state of systemic inflammation, which exacerbates blood-brain barrier disruption. The resulting neuroinflammation and oxidative stress in the mouse hippocampus likely contribute to the significant cognitive decline observed in aged obese animals. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Discussion

NASA Astrophysics Data System (ADS)

Marshall, Tim

Presenter, Jim McDonald, Texas Tech University [McDonald, this volume, Damage mitigation and occupant safety]. (Arnold Court, California State University.) Can you tell me how to park my car to mitigate tornado damage?

Conceptual framework for improved wind-related forest threat assessment in the Southeastern United States

Treesearch

Scott L. Goodrick; John A. Stanturf

2010-01-01

In the Southeastern United States, forests are subject to a variety of damage-causing wind phenomena that range in scale from very localized (downbursts and tornadoes) to broad spatial scales (hurricanes). Incorporating the threat of wind damage into forest management plans requires tools capable of assessing risk across this range of scales. Our conceptual approach...

Hurricane Irene and associated floods of August 27-30, 2011, in New Jersey

USGS Publications Warehouse

Watson, Kara M.; Collenburg, Jerilyn V.; Reiser, Robert G.

2013-01-01

About 1 million people across the State were evacuated, and every county was eventually declared a Federal disaster area. Property damage in New Jersey was estimated to be $1 billion. Governor Chris Christie declared a State of Emergency for New Jersey on August 31, 2011. After assessment of the damage by the Federal Emergency Management Agency, President Obama declared all 21 counties major disaster areas in the State of New Jersey on August 31, 2011.

Female plumage colour influences seasonal oxidative damage and testosterone profiles in a songbird.

PubMed

Vitousek, Maren N; Stewart, Rosemary A; Safran, Rebecca J

2013-10-23

Across diverse taxa, morphological traits mediate social interactions and mate selection. Physiological constraints on signal elaboration have been widely documented, but the potential for trait display to influence physiological state remains poorly understood. We tested for the presence of causal links between ventral plumage colour-a trait known to covary with reproductive performance-and physiological measures in female North American barn swallows, Hirundo rustica erythrogaster. Naturally darker swallows have lower levels of plasma oxidative damage. Females manipulated to display darker ventral plumage during reproduction rapidly decreased oxidative damage, adopting the physiological state of naturally darker individuals. These results support the presence of a social mechanism that links static plumage traits with the physiological state of their bearer during trait advertisement, long after the completion of signal development.

Female plumage colour influences seasonal oxidative damage and testosterone profiles in a songbird

PubMed Central

Vitousek, Maren N.; Stewart, Rosemary A.; Safran, Rebecca J.

2013-01-01

Across diverse taxa, morphological traits mediate social interactions and mate selection. Physiological constraints on signal elaboration have been widely documented, but the potential for trait display to influence physiological state remains poorly understood. We tested for the presence of causal links between ventral plumage colour—a trait known to covary with reproductive performance—and physiological measures in female North American barn swallows, Hirundo rustica erythrogaster. Naturally darker swallows have lower levels of plasma oxidative damage. Females manipulated to display darker ventral plumage during reproduction rapidly decreased oxidative damage, adopting the physiological state of naturally darker individuals. These results support the presence of a social mechanism that links static plumage traits with the physiological state of their bearer during trait advertisement, long after the completion of signal development. PMID:23966597

Effects of Lightning Injection on Power-MOSFETs

NASA Technical Reports Server (NTRS)

Celaya, Jose; Saha, Sankalita; Wysocki, Phil; Ely, Jay; Nguyen, Truong; Szatkowski, George; Koppen, Sandra; Mielnik, John; Vaughan, Roger; Goebel, Kai

2009-01-01

Lightning induced damage is one of the major concerns in aircraft health monitoring. Such short-duration high voltages can cause significant damage to electronic devices. This paper presents a study on the effects of lightning injection on power metal-oxide semiconductor field effect transistors (MOSFETs). This approach consisted of pin-injecting lightning waveforms into the gate, drain and/or source of MOSFET devices while they were in the OFF-state. Analysis of the characteristic curves of the devices showed that for certain injection modes the devices can accumulate considerable damage rendering them inoperable. Early results demonstrate that a power MOSFET, even in its off-state, can incur considerable damage due to lightning pin injection, leading to significant deviation in its behavior and performance, and to possibly early device failures.

49 CFR 579.21 - Reporting requirements for manufacturers of 5,000 or more light vehicles annually.

Code of Federal Regulations, 2010 CFR

2010-10-01

... codes to be included. (c) Numbers of property damage claims, consumer complaints, warranty claims, and field reports. Separate reports on the numbers of those property damage claims, consumer complaints... report shall state, separately by each such code, the number of such property damage claims, consumer...

Multi-physics damage sensing in nano-engineered structural composites.

PubMed

de Villoria, Roberto Guzmán; Yamamoto, Namiko; Miravete, Antonio; Wardle, Brian L

2011-05-06

Non-destructive evaluation techniques can offer viable diagnostic and prognostic routes to mitigating failures in engineered structures such as bridges, buildings and vehicles. However, existing techniques have significant drawbacks, including poor spatial resolution and limited in situ capabilities. We report here a novel approach where structural advanced composites containing electrically conductive aligned carbon nanotubes (CNTs) are ohmically heated via simple electrical contacts, and damage is visualized via thermographic imaging. Damage, in the form of cracks and other discontinuities, usefully increases resistance to both electrical and thermal transport in these materials, which enables tomographic full-field damage assessment in many cases. Characteristics of the technique include the ability for real-time measurement of the damage state during loading, low-power operation (e.g. 15 °C rise at 1 W), and beyond state-of-the-art spatial resolution for sensing damage in composites. The enhanced thermographic technique is a novel and practical approach for in situ monitoring to ascertain structural health and to prevent structural failures in engineered structures such as aerospace and automotive vehicles and wind turbine blades, among others.

Multi-physics damage sensing in nano-engineered structural composites

NASA Astrophysics Data System (ADS)

Guzmán de Villoria, Roberto; Yamamoto, Namiko; Miravete, Antonio; Wardle, Brian L.

2011-05-01

Non-destructive evaluation techniques can offer viable diagnostic and prognostic routes to mitigating failures in engineered structures such as bridges, buildings and vehicles. However, existing techniques have significant drawbacks, including poor spatial resolution and limited in situ capabilities. We report here a novel approach where structural advanced composites containing electrically conductive aligned carbon nanotubes (CNTs) are ohmically heated via simple electrical contacts, and damage is visualized via thermographic imaging. Damage, in the form of cracks and other discontinuities, usefully increases resistance to both electrical and thermal transport in these materials, which enables tomographic full-field damage assessment in many cases. Characteristics of the technique include the ability for real-time measurement of the damage state during loading, low-power operation (e.g. 15 °C rise at 1 W), and beyond state-of-the-art spatial resolution for sensing damage in composites. The enhanced thermographic technique is a novel and practical approach for in situ monitoring to ascertain structural health and to prevent structural failures in engineered structures such as aerospace and automotive vehicles and wind turbine blades, among others.

High-speed imaging and small-scale explosive characterization techniques to understand effects of primary blast-induced injury on nerve cell structure and function

NASA Astrophysics Data System (ADS)

Piehler, T.; Banton, R.; Zander, N.; Duckworth, J.; Benjamin, R.; Sparks, R.

2018-01-01

Traumatic brain injury (TBI) is often associated with blast exposure. Even in the absence of penetrating injury or evidence of tissue injury on imaging, blast TBI may trigger a series of neural/glial cellular and functional changes. Unfortunately, the diagnosis and proper treatment of mild traumatic brain injury (mTBI) caused by explosive blast is challenging, as it is not easy to clinically distinguish blast from non-blast TBI on the basis of patient symptoms. Damage to brain tissue, cell, and subcellular structures continues to occur slowly and in a manner undetectable by conventional imaging techniques. The threshold shock impulse levels required to induce damage and the cumulative effects upon multiple exposures are not well characterized. Understanding how functional and structural damage from realistic blast impact at cellular and tissue levels at variable timescales after mTBI events may be vital for understanding this injury phenomenon and for linking mechanically induced structural changes with measurable effects on the nervous system. Our working hypothesis is that there is some transient physiological dysfunction occurring at cellular and subcellular levels within the central nervous system due to primary blast exposure. We have developed a novel in vitro indoor experimental system that uses real military explosive charges to more accurately represent military blast exposure and to probe the effects of primary explosive blast on dissociated neurons. We believe this system offers a controlled experimental method to analyze and characterize primary explosive blast-induced cellular injury and to understand threshold injury phenomenon. This paper will also focus on the modeling aspect of our work and how it relates to the experimental work.

Strength and failure of a damaged material

DOE PAGES

Cerreta, Ellen K.; Gray III, George T.; Trujillo, Carl P.; ...

2015-09-07

Under complex, dynamic loading conditions, damage can occur within a material. Should this damage not lead to catastrophic failure, the material can continue to sustain further loading. But, little is understood about how to represent the mechanical response of a material that has experienced dynamic loading leading to incipient damage. We examine this effect in copper. Copper is shock loaded to impart an incipient state of damage to the material. Thereafter compression and tensile specimens were sectioned from the dynamically damaged specimen to quantify the subsequent properties of the material in the region of intense incipient damage and in regionsmore » far from the damage. Finally, we observed that enhanced yield stresses result from the damaged material even over material, which has simply been shock loaded and not damaged. These results are rationalized in terms of stored plastic work due to the damage process.« less

Strength and failure of a damaged material

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

Cerreta, Ellen K.; Gray III, George T.; Trujillo, Carl P.

Under complex, dynamic loading conditions, damage can occur within a material. Should this damage not lead to catastrophic failure, the material can continue to sustain further loading. But, little is understood about how to represent the mechanical response of a material that has experienced dynamic loading leading to incipient damage. We examine this effect in copper. Copper is shock loaded to impart an incipient state of damage to the material. Thereafter compression and tensile specimens were sectioned from the dynamically damaged specimen to quantify the subsequent properties of the material in the region of intense incipient damage and in regionsmore » far from the damage. Finally, we observed that enhanced yield stresses result from the damaged material even over material, which has simply been shock loaded and not damaged. These results are rationalized in terms of stored plastic work due to the damage process.« less

Anthocyanins extracted from black soybean seed coat protect primary cortical neurons against in vitro ischemia.

PubMed

Bhuiyan, Mohammad Iqbal Hossain; Kim, Joo Youn; Ha, Tae Joung; Kim, Seong Yun; Cho, Kyung-Ok

2012-01-01

The present study investigated the neuroprotective effects of anthocyanins extracted from black soybean (cv. Cheongja 3, Glycine max (L.) MERR.) seed coat against oxygen-glucose deprivation (OGD) and glutamate-induced cell death in rat primary cortical neurons. Lactate dehydrogenase (LDH) release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assays were employed to assess cell membrane damage and viability of primary neurons, respectively. OGD-induced cell death in 7 d in vitro primary cortical neurons was found to be OGD duration-dependent, and approximately 3.5 h of OGD resulted in ≈60% cell death. Treatment with black soybean anthocyanins dose-dependently prevented membrane damage and increased the viability of primary neurons that were exposed to OGD. Glutamate-induced neuronal cell death was dependent on the glutamate concentration at relatively low concentrations and the number of days the cells remained in culture. Interestingly, black soybean anthocyanins did not protect against glutamate-induced neuronal cell death. They did, however, inhibit the excessive generation of reactive oxygen species (ROS) and preserve mitochondrial membrane potential (MMP) in primary neurons exposed to OGD. In agreement with the neuroprotective effect of crude black soybean anthocyanins, purified cyanidin-3-glucoside (C3G), the major component of anthocyanins, also offered dose-dependent neuroprotection against OGD-induced neuronal cell death. Moreover, black soybean C3G markedly prevented excessive generation of ROS and preserved MMP in primary neurons that were exposed to OGD. Collectively, these results suggest that the neuroprotection of primary rat cortical neurons by anthocyanins that were extracted from black soybean seed coat might be mediated through oxidative stress inhibition and MMP preservation but not through glutamate-induced excitotoxicity attenuation.

Electron Damage Effects on Carbon Nanotube Thin Films

DTIC Science & Technology

2013-03-01

ELECTRON DAMAGE EFFECTS ON CARBON NANOTUBE THIN FILMS THESIS Jeremy S. Best, Captain, USMC AFIT-ENP-13-M-37 DEPARTMENT OF THE AIR FORCE AIR...Government and is not subject to copyright protection in the United States. AFIT-ENP-13-M-37 ELECTRON DAMAGE EFFECTS ON CARBON NANOTUBE THIN FILMS...M-37 ELECTRON DAMAGE EFFECTS ON CARBON NANOTUBE THIN FILMS Jeremy S. Best, BS Aerospace Engineering Captain, USMC Approved: Dr. John McClory

A Comparative Analysis of Teacher Supply and Pupils' Enrolment in Public and Private Primary Schools in Kwara and Ekiti States, Nigeria

ERIC Educational Resources Information Center

Adeyemi, T. O.

2012-01-01

This study investigated teacher supply and pupils' enrolment in public and private primary schools in Kwara and Ekiti States, Nigeria. The study population comprised all the 811 primary schools in Kwara State and 810 primary schools in Ekiti State. Out of the forty-seven higher institutions that supply teachers to primary schools in the two…

White matter damage in primary progressive aphasias: a diffusion tensor tractography study

PubMed Central

Galantucci, Sebastiano; Tartaglia, Maria Carmela; Wilson, Stephen M.; Henry, Maya L.; Filippi, Massimo; Agosta, Federica; Dronkers, Nina F.; Henry, Roland G.; Ogar, Jennifer M.; Miller, Bruce L.

2011-01-01

Primary progressive aphasia is a clinical syndrome that encompasses three major phenotypes: non-fluent/agrammatic, semantic and logopenic. These clinical entities have been associated with characteristic patterns of focal grey matter atrophy in left posterior frontoinsular, anterior temporal and left temporoparietal regions, respectively. Recently, network-level dysfunction has been hypothesized but research to date has focused largely on studying grey matter damage. The aim of this study was to assess the integrity of white matter tracts in the different primary progressive aphasia subtypes. We used diffusion tensor imaging in 48 individuals: nine non-fluent, nine semantic, nine logopenic and 21 age-matched controls. Probabilistic tractography was used to identify bilateral inferior longitudinal (anterior, middle, posterior) and uncinate fasciculi (referred to as the ventral pathway); and the superior longitudinal fasciculus segmented into its frontosupramarginal, frontoangular, frontotemporal and temporoparietal components, (referred to as the dorsal pathway). We compared the tracts’ mean fractional anisotropy, axial, radial and mean diffusivities for each tract in the different diagnostic categories. The most prominent white matter changes were found in the dorsal pathways in non-fluent patients, in the two ventral pathways and the temporal components of the dorsal pathways in semantic variant, and in the temporoparietal component of the dorsal bundles in logopenic patients. Each of the primary progressive aphasia variants showed different patterns of diffusion tensor metrics alterations: non-fluent patients showed the greatest changes in fractional anisotropy and radial and mean diffusivities; semantic variant patients had severe changes in all metrics; and logopenic patients had the least white matter damage, mainly involving diffusivity, with fractional anisotropy altered only in the temporoparietal component of the dorsal pathway. This study demonstrates that both careful dissection of the main language tracts and consideration of all diffusion tensor metrics are necessary to characterize the white matter changes that occur in the variants of primary progressive aphasia. These results highlight the potential value of diffusion tensor imaging as a new tool in the multimodal diagnostic evaluation of primary progressive aphasia. PMID:21666264

Simulation of earthquake caused building damages for the development of fast reconnaissance techniques

NASA Astrophysics Data System (ADS)

Schweier, C.; Markus, M.; Steinle, E.

2004-04-01

Catastrophic events like strong earthquakes can cause big losses in life and economic values. An increase in the efficiency of reconnaissance techniques could help to reduce the losses in life as many victims die after and not during the event. A basic prerequisite to improve the rescue teams' work is an improved planning of the measures. This can only be done on the basis of reliable and detailed information about the actual situation in the affected regions. Therefore, a bundle of projects at Karlsruhe university aim at the development of a tool for fast information retrieval after strong earthquakes. The focus is on urban areas as the most losses occur there. In this paper the approach for a damage analysis of buildings will be presented. It consists of an automatic methodology to model buildings in three dimensions, a comparison of pre- and post-event models to detect changes and a subsequent classification of the changes into damage types. The process is based on information extraction from airborne laserscanning data, i.e. digital surface models (DSM) acquired through scanning of an area with pulsed laser light. To date, there are no laserscanning derived DSMs available to the authors that were taken of areas that suffered damages from earthquakes. Therefore, it was necessary to simulate such data for the development of the damage detection methodology. In this paper two different methodologies used for simulating the data will be presented. The first method is to create CAD models of undamaged buildings based on their construction plans and alter them artificially in such a way as if they had suffered serious damage. Then, a laserscanning data set is simulated based on these models which can be compared with real laserscanning data acquired of the buildings (in intact state). The other approach is to use measurements of actual damaged buildings and simulate their intact state. It is possible to model the geometrical structure of these damaged buildings based on digital photography taken after the event by evaluating the images with photogrammetrical methods. The intact state of the buildings is simulated based on on-site investigations, and finally laserscanning data are simulated for both states.

Critical and subcritical damage monitoring of bonded composite repairs using innovative non-destructive techniques

NASA Astrophysics Data System (ADS)

Grammatikos, S. A.; Kordatos, E. Z.; Aggelis, D. G.; Matikas, T. E.; Paipetis, A. S.

2012-04-01

Infrared Thermography (IrT) has been shown to be capable of detecting and monitoring service induced damage of repair composite structures. Full-field imaging, along with portability are the primary benefits of the thermographic technique. On-line lock-in thermography has been reported to successfully monitor damage propagation or/and stress concentration in composite coupons, as mechanical stresses in structures induce heat concentration phenomena around flaws. During mechanical fatigue, cyclic loading plays the role of the heating source and this allows for critical and subcritical damage identification and monitoring using thermography. The Electrical Potential Change Technique (EPCT) is a new method for damage identification and monitoring during loading. The measurement of electrical potential changes at specific points of Carbon Fiber Reinforced Polymers (CFRPs) under load are reported to enable the monitoring of strain or/and damage accumulation. Along with the aforementioned techniques Finally, Acoustic Emission (AE) method is well known to provide information about the location and type of damage. Damage accumulation due to cyclic loading imposes differentiation of certain parameters of AE like duration and energy. Within the scope of this study, infrared thermography is employed along with AE and EPCT methods in order to assess the integrity of bonded repair patches on composite substrates and to monitor critical and subcritical damage induced by the mechanical loading. The combined methodologies were effective in identifying damage initiation and propagation of bonded composite repairs.

Protection and Dissection of Recurrent Laryngeal Nerve in Salvage Thyroid Cancer Surgery to Patients with Insufficient Primary Operation Extent and Suspicious Residual Tumor.

PubMed

Yu, Wen-Bin; Zhang, Nai-Song

2015-01-01

Some thyroid cancer patients undergone insufficient tumor removal in the primary surgery in China . our aim is to evaluate the impact of dissection of the recurrent laryngeal nerve during a salvage thyroid cancer operation in these patients to prevent nerve injury. Clinical data of 49 enrolled patients who received a salvage thyroid operation were retrospectively reviewed. Primary pathology was thyroid papillary cancer. The initial procedure performed included nodulectomy (20 patients), partial thyroidectomy (19 patients) and subtotal thyroidectomy (10 patients). The effect of dissection and protection of the recurrent laryngeal nerve and the mechanism of nerve injury were studied. The cervical courses of the recurrent laryngeal nerves were successfully dissected in all cases. Nerves were adherent to or involved by scars in 22 cases. Three were ligated near the place where the nerve entered the larynx, while another three were cut near the intersection of inferior thyroid artery with the recurrent laryngeal nerve. Light hoarseness occurred to four patients without a preoperative voice change. In conclusion, accurate primary diagnosis allows for a sufficient primary operation to be performed, avoiding insufficient tumor removal that requires a secondary surgery. The most important cause of nerve damage resulted from not identifying the recurrent laryngeal nerve during first surgery , and meticulous dissection during salvage surgery was the most efficient method to avoid nerve damage.

Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis

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

Ma, Jiali; Hui, Pingping; Meng, Wenying

The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificatedmore » when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells. - Highlights: • Ku70 knockdown sensitizes gemcitabine-induced killing of pancreatic cancer cells. • Ku70 knockdown facilitates gemcitabine-induced DNA damage and cell apoptosis. • Ku70 overexpression deceases gemcitabine's sensitivity in pancreatic cancer cells. • Ku70 knockdown sensitizes gemcitabine-induced anti-tumor activity in vivo.« less

Sodium transport through the cerebral sodium-glucose transporter exacerbates neuron damage during cerebral ischaemia.

PubMed

Yamazaki, Yui; Harada, Shinichi; Wada, Tetsuyuki; Yoshida, Shigeru; Tokuyama, Shogo

2016-07-01

We recently demonstrated that the cerebral sodium-glucose transporter (SGLT) is involved in postischaemic hyperglycaemia-induced exacerbation of cerebral ischaemia. However, the associated SGLT-mediated mechanisms remain unclear. Thus, we examined the involvement of cerebral SGLT-induced excessive sodium ion influx in the development of cerebral ischaemic neuronal damage. [Na+]i was estimated according to sodium-binding benzofuran isophthalate fluorescence. In the in vitro study, primary cortical neurons were prepared from fetuses of ddY mice. Primary cortical neurons were cultured for 5 days before each treatment with reagents, and these survival rates were assessed using biochemical assays. In in vivo study, a mouse model of focal ischaemia was generated using middle cerebral artery occlusion (MCAO). In these experiments, treatment with high concentrations of glucose induced increment in [Na+]i, and this phenomenon was suppressed by the SGLT-specific inhibitor phlorizin. SGLT-specific sodium ion influx was induced using a-methyl-D-glucopyranoside (a-MG) treatments, which led to significant concentration-dependent declines in neuronal survival rates and exacerbated hydrogen peroxide-induced neuronal cell death. Moreover, phlorizin ameliorated these effects. Finally, intracerebroventricular administration of a-MG exacerbated the development of neuronal damage induced by MCAO, and these effects were ameliorated by the administration of phlorizin. Hence, excessive influx of sodium ions into neuronal cells through cerebral SGLT may exacerbate the development of cerebral ischaemic neuronal damage. © 2016 Royal Pharmaceutical Society.

Mouse Cytomegalovirus Infection in BALB/c Mice Resembles Virus-Associated Secondary Hemophagocytic Lymphohistiocytosis and Shows a Pathogenesis Distinct from Primary Hemophagocytic Lymphohistiocytosis.

PubMed

Brisse, Ellen; Imbrechts, Maya; Put, Karen; Avau, Anneleen; Mitera, Tania; Berghmans, Nele; Rutgeerts, Omer; Waer, Mark; Ninivaggi, Marisa; Kelchtermans, Hilde; Boon, Louis; Snoeck, Robert; Wouters, Carine H; Andrei, Graciela; Matthys, Patrick

2016-04-01

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immunological disorder that is characterized by systemic inflammation, widespread organ damage, and hypercytokinemia. Primary HLH is caused by mutations in granule-mediated cytotoxicity, whereas secondary HLH occurs, without a known genetic background, in a context of infections, malignancies, or autoimmune and autoinflammatory disorders. Clinical manifestations of both HLH subtypes are often precipitated by a viral infection, predominantly with Herpesviridae. Exploiting this knowledge, we established an animal model of virus-associated secondary HLH by infecting immunocompetent wild-type mice with the β-herpesvirus murine CMV. C57BL/6 mice developed a mild inflammatory phenotype, whereas BALB/c mice displayed the clinicopathologic features of HLH, as set forth in the Histiocyte Society diagnostic guidelines: fever, cytopenia, hemophagocytosis, hyperferritinemia, and elevated serum levels of soluble CD25. BALB/c mice also developed lymphadenopathy, liver dysfunction, and decreased NK cell numbers. Lymphoid and myeloid cells were in a hyperactivated state. Nonetheless, depletion of CD8(+) T cells could not inhibit or cure the HLH-like syndrome, highlighting a first dissimilarity from mouse models of primary HLH. Immune cell hyperactivation in BALB/c mice was accompanied by a cytokine storm. Notably, plasma levels of IFN-γ, a key pathogenic cytokine in models of primary HLH, were the highest. Nevertheless, murine CMV-infected IFN-γ-deficient mice still developed the aforementioned HLH-like symptoms. In fact, IFN-γ-deficient mice displayed a more complete spectrum of HLH, including splenomegaly, coagulopathy, and decreased NK cell cytotoxicity, indicating a regulatory role for IFN-γ in the pathogenesis of virus-associated secondary HLH as opposed to its central pathogenic role in primary HLH. Copyright © 2016 by The American Association of Immunologists, Inc.

Mitochondrial redox system, dynamics, and dysfunction in lung inflammaging and COPD.

PubMed

Lerner, Chad A; Sundar, Isaac K; Rahman, Irfan

2016-12-01

Myriad forms of endogenous and environmental stress disrupt mitochondrial function by impacting critical processes in mitochondrial homeostasis, such as mitochondrial redox system, oxidative phosphorylation, biogenesis, and mitophagy. External stressors that interfere with the steady state activity of mitochondrial functions are generally associated with an increase in reactive oxygen species, inflammatory response, and induction of cellular senescence (inflammaging) potentially via mitochondrial damage associated molecular patterns (DAMPS). Many of these are the key events in the pathogenesis of chronic obstructive pulmonary disease (COPD) and its exacerbations. In this review, we highlight the primary mitochondrial quality control mechanisms that are influenced by oxidative stress/redox system, including role of mitochondria during inflammation and cellular senescence, and how mitochondrial dysfunction contributes to the pathogenesis of COPD and its exacerbations via pathogenic stimuli. Copyright © 2016 Elsevier Ltd. All rights reserved.

Allergic to people: building bridges in a ripped psychic-soma.

PubMed

Teitelbaum, Stefanie

2008-06-01

An exploration of the use mind/body metaphors in a woman whose physical, environmental and psychoneurotic trauma culminated in an irreversible colostomy. She lived in a world of concrete symbols, her primary process damaged such that she could not create generative symbols to process her trauma. She regressed to a state of infantile megalomania, recoiling from the external reality of subjective others. Her introjective disorder mirrored her digestive disorder as she could absorb neither good objects nor good nutrients. The analytic situation has been an auxiliary fecal container and we work to bridge her mind body split with mind/body metaphors. As she reclaims lost development mastery, she displays a symbolized sphincter. As her capacity to form symbols grows, she rages and mourns for the loss of her fantasized ideal parents and her ideal body.

Cancer as a Risk Factor for Cardiovascular Disease.

PubMed

Giza, Dana Elena; Iliescu, Gloria; Hassan, Saamir; Marmagkiolis, Konstantinos; Iliescu, Cezar

2017-06-01

Improvements in early diagnosis and cancer treatments have contributed to high survival rates for many cancer patients. However, these patients often die of cardiovascular disease rather than recurrence of their cancer. Heart disease manifesting after cancer may be due to several mechanisms: shared cardiovascular risks between cancer and cardiovascular disease, inflammatory states associated with malignancies, and/or cardiotoxic effects of cancer therapy. Cancer treatment increases the risk of cardiovascular diseases directly by damaging critical structures of the heart or indirectly by promoting accelerated atherosclerosis. Estimating cardiovascular risk by using advanced imaging and monitoring of the cardiac biomarkers can be used for early detection and treatment of subclinical cardiac injury. Better knowledge of these early and late cardiac effects in cancer patients will enable adoption of both primary and secondary prevention measures of long-term treatment complications in cancer survivors.

Effects of moisture, residual thermal curing stresses and mechanical load on the damage development in quasi-isotropic laminates

NASA Technical Reports Server (NTRS)

Kriz, R. D.; Stinchcomb, W. W.; Tenney, D. R.

1980-01-01

Classical laminate theory and a finite element model were used to predict stress states prior to the first formation of damage in laminates fabricated from T/300/5208. Crack patterns characteristic of the laminate in a wet or dry condition were also predicted using a shear lag model. Development of edge damage was recorded and observed during the test by transferring an image of the damage from the edge surface on to a thin acetate sheet such that the damage imprinted could be immediately viewed on a microfiche card reader. Moisture was shown to significantly alter the interior and edge dry stress states due to swelling and a reduction of elastic properties and to reduce the transverse strength in 90 deg plies. A model was developed in order to predict changes in first ply failure laminate loads due to differences in stacking sequence together with a wet or dry environmental condition.

Impact damage resistance of composite fuselage structure, part 1

NASA Technical Reports Server (NTRS)

Dost, E. F.; Avery, W. B.; Ilcewicz, L. B.; Grande, D. H.; Coxon, B. R.

1992-01-01

The impact damage resistance of laminated composite transport aircraft fuselage structures was studied experimentally. A statistically based designed experiment was used to examine numerous material, laminate, structural, and extrinsic (e.g., impactor type) variables. The relative importance and quantitative measure of the effect of each variable and variable interactions on responses including impactor dynamic response, visibility, and internal damage state were determined. The study utilized 32 three-stiffener panels, each with a unique combination of material type, material forms, and structural geometry. Two manufacturing techniques, tow placement and tape lamination, were used to build panels representative of potential fuselage crown, keel, and lower side-panel designs. Various combinations of impactor variables representing various foreign-object-impact threats to the aircraft were examined. Impacts performed at different structural locations within each panel (e.g., skin midbay, stiffener attaching flange, etc.) were considered separate parallel experiments. The relationship between input variables, measured damage states, and structural response to this damage are presented including recommendations for materials and impact test methods for fuselage structure.

Medical Malpractice Damage Caps and Provider Reimbursement.

PubMed

Friedson, Andrew I

2017-01-01

A common state legislative maneuver to combat rising healthcare costs is to reform the tort system by implementing caps on noneconomic damages awardable in medical malpractice cases. Using the implementation of caps in several states and large database of private insurance claims, I estimate the effect of damage caps on the amount providers charge to insurance companies as well as the amount that insurance companies reimburse providers for medical services. The amount providers charge insurers is unresponsive to tort reform, but the amount that insurers reimburse providers decreases for some procedures. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

32 CFR 536.77 - Applicable law for claims under the Military Claims Act.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) The United States will only be liable for the portion of loss or damage attributable to the fault of... preparation and presentation of the claim. (vi) Punitive or exemplary damages are not payable. (vii) Claims... will be considered as an element of damages under paragraph (b)(3)(ii) of this section. Claims for...

32 CFR 536.77 - Applicable law for claims under the Military Claims Act.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) The United States will only be liable for the portion of loss or damage attributable to the fault of... preparation and presentation of the claim. (vi) Punitive or exemplary damages are not payable. (vii) Claims... will be considered as an element of damages under paragraph (b)(3)(ii) of this section. Claims for...

32 CFR 536.77 - Applicable law for claims under the Military Claims Act.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) The United States will only be liable for the portion of loss or damage attributable to the fault of... preparation and presentation of the claim. (vi) Punitive or exemplary damages are not payable. (vii) Claims... will be considered as an element of damages under paragraph (b)(3)(ii) of this section. Claims for...

Wildfire risk adaptation: propensity of forestland owners to purchase wildfire insurance in the southern United States

Treesearch

Jianbang Gan; Adam Jarrett; Cassandra Johnson Gaither

2014-01-01

Economic and ecological damages caused by wildfire are alarming, and such damages are expected to rise with changes in wildfire regimes, calling for more effective wildfire mitigation and adaptation strategies. Among wildfire adaptation options for forestland owners is purchasing wildfire insurance, which provides compensation to those insured if a wildfire damages...

43 CFR 11.91 - How does the authorized official seek recovery of the assessed damages from the potentially...

Code of Federal Regulations, 2010 CFR

2010-10-01

...: Interior Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Post-Assessment Phase... performed by a Federal or State official in accordance with this part, the natural resource damage... location and description of the injured resource, the type of discharge or release determined to have...

43 CFR 11.91 - How does the authorized official seek recovery of the assessed damages from the potentially...

Code of Federal Regulations, 2011 CFR

2011-10-01

...: Interior Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE ASSESSMENTS Post-Assessment Phase... performed by a Federal or State official in accordance with this part, the natural resource damage... location and description of the injured resource, the type of discharge or release determined to have...

Incidence and impact of damage to Virginia's timber, 1986

Treesearch

Cindy M. Huber; Joe P. McClure; Noel D. Cost

1987-01-01

This bulletin reports survey data on agents damaging trees in Virginia's forests. Data were collected in 1984 and 1985 by the Forest Inventory and Analysis Work Unit of the Southeastern Forest Experiment Station. This effort was part of the fifth inventory of the State's forests. Damage information similiar to the previous survey was gathered for this...

Ecological risk assessment to support fuels treatment project decisions

Treesearch

Jay O' Laughlin

2010-01-01

Risk is a combined statement of the probability that something of value will be damaged and some measure of the damage’s adverse effect. Wildfires burning in the uncharacteristic fuel conditions now typical throughout the Western United States can damage ecosystems and adversely affect environmental conditions. Wildfire behavior can be modified by prefire fuel...

[Ophthalmological opinions for liability affairs material damage (Part I) (author's transl)].

PubMed

Burggraf, H

1979-02-01

German law abides anyone reponsible for the damage he or she has caused to another person's property or corporal integrity. This includes all medical costs directed towards the restitution of health as well as economical damage in direct consequence of the corporal damage. An ophthalmological expert is to state his opinion therefore in accordance with the specific conditions of every individual case and not just according to general charts. Financial compensation is only granted for the actual results of damage inquestion. Prior damage and disability have to be remarked but not to justify a financial compensation. The question of smart-money is dealt with in Part II.

3D Microstructures for Materials and Damage Models

DOE PAGES

Livescu, Veronica; Bronkhorst, Curt Allan; Vander Wiel, Scott Alan

2017-02-01

Many challenges exist with regard to understanding and representing complex physical processes involved with ductile damage and failure in polycrystalline metallic materials. Currently, the ability to accurately predict the macroscale ductile damage and failure response of metallic materials is lacking. Research at Los Alamos National Laboratory (LANL) is aimed at building a coupled experimental and computational methodology that supports the development of predictive damage capabilities by: capturing real distributions of microstructural features from real material and implementing them as digitally generated microstructures in damage model development; and, distilling structure-property information to link microstructural details to damage evolution under a multitudemore » of loading states.« less

Biological research on fire in the West

USGS Publications Warehouse

,

2005-01-01

Wildland fires are a natural feature of many ecosystems, including grasslands, forests, and shrublands. How-ever, years of fire exclusion have led to accumulations of dead fuels and increases in the density of fire-intolerant species. In most western states, recent fires burning in these altered ecosystems have caused significant damage and huge economic losses to homes, busi-nesses, and communities. They also have dis-turbed forests and rangelands as well as their associated watersheds, plants, and animals. Every western state is concerned about dam-age from such catastrophic fires, and there is strong interest from all sectors in prevent-ing and reducing the resulting damage in the future. There is also interest in the use of fire as a management tool for reducing hazards and restoring damaged ecosystems and for returning fire to its natural role in wilderness ecosystems.

[Amyotrophic lateral sclerosis and exposure to metals and other occupational/environmental hazardous materials: state of the art].

PubMed

Garzillo, Elpidio Maria; Miraglia, Nadia; Pedata, Paola; Feola, Daniela; Sannolo, Nicola; Lamberti, Monica

2015-01-01

In recent years, scientific literature has been giving more and more importance to the study of the occupational/environmental exposure to risk agents related to the onset of Amyotrophic Lateral Sclerosis (ALS), a neurodegenerative disease characterized by progressive muscular paralysis reflecting degeneration of motor neurons in the primary motor cortex. Aim of this work is to verify the state of art about the eventual role of occupational/environmental exposure to risk agents. Selected articles, on the basis of keywords, year of publication and topics, are related to occupational and environmental exposure to xenobiotics, and, in particular, to the exposure to heavy metals that could lead to neuronal damage mechanisms involved in ALS onset. The review shows that although the scientific production has increased the interest in the evaluation of extra-genetic causes of ALS onset, there are still few studies concerning the careful study of the work activities of the individual patient, and the inferences that can be drawn to date about the possible connection between occupational exposure to risk factors and the onset of ALS are still lacking.

On experimental damage localization by SP2E: Application of H∞ estimation and oblique projections

NASA Astrophysics Data System (ADS)

Lenzen, Armin; Vollmering, Max

2018-05-01

In this article experimental damage localization based on H∞ estimation and state projection estimation error (SP2E) is studied. Based on an introduced difference process, a state space representation is derived for advantageous numerical solvability. Because real structural excitations are presumed to be unknown, a general input is applied therein, which allows synchronization and normalization. Furthermore, state projections are introduced to enhance damage identification. While first experiments to verify method SP2E have already been conducted and published, further laboratory results are analyzed here. Therefore, SP2E is used to experimentally localize stiffness degradations and mass alterations. Furthermore, the influence of projection techniques is analyzed. In summary, method SP2E is able to localize structural alterations, which has been observed by results of laboratory experiments.

Genetics Home Reference: primary spontaneous pneumothorax

MedlinePlus

... may play a role in repairing and re-forming lung tissue following damage. Researchers have not determined ... during growth spurts may increase the likelihood of forming blebs. Long-term smoking also greatly increases the ...

Medical malpractice reform and employer-sponsored health insurance premiums.

PubMed

Morrisey, Michael A; Kilgore, Meredith L; Nelson, Leonard Jack

2008-12-01

Tort reform may affect health insurance premiums both by reducing medical malpractice premiums and by reducing the extent of defensive medicine. The objective of this study is to estimate the effects of noneconomic damage caps on the premiums for employer-sponsored health insurance. Employer premium data and plan/establishment characteristics were obtained from the 1999 through 2004 Kaiser/HRET Employer Health Insurance Surveys. Damage caps were obtained and dated based on state annotated codes, statutes, and judicial decisions. Fixed effects regression models were run to estimate the effects of the size of inflation-adjusted damage caps on the weighted average single premiums. State tort reform laws were identified using Westlaw, LEXIS, and statutory compilations. Legislative repeal and amendment of statutes and court decisions resulting in the overturning or repealing state statutes were also identified using LEXIS. Using a variety of empirical specifications, there was no statistically significant evidence that noneconomic damage caps exerted any meaningful influence on the cost of employer-sponsored health insurance. The findings suggest that tort reforms have not translated into insurance savings.

Nonlinear dynamics and damage induced properties of soft matter with application in oncology

NASA Astrophysics Data System (ADS)

Naimark, O.

2017-09-01

Molecular-morphological signs of oncogenesis could be linked to multiscale collective effects in molecular, cell and tissue related to defects (damage) dynamics. It was shown that nonlinear behavior of biological systems can be linked to the existence of characteristic collective open state modes providing the coherent expression dynamics. New type of criticality in nonequilibrium systems with defects—structural-scaling transition allows the definition of the `driving force' for a biological soft matter related to consolidated open states. The set of collective open states (breathers, autosolitons and blow-up modes) in the molecular ensembles provides the collective expression dynamics to attract the entire system (cell, tissue) toward a few preferred global states. The co-existence of three types of collective modes determines the multifractal scenario of biological soft matter dynamics. The appearance of `globally convergent' dynamics corresponding to the coherent behavior of multiscale blow-up open states (blow-up gene expression) leads to anomalous localized softening (blow-up localized damage) and the subjection of the cells (or tissue) to monofractal dynamics. This dynamics can be associated with cancer progression.

Oxidative Stress and Heart Failure in Altered Thyroid States

PubMed Central

Mishra, Pallavi; Samanta, Luna

2012-01-01

Increased or reduced action of thyroid hormone on certain molecular pathways in the heart and vasculature causes relevant cardiovascular derangements. It is well established that hyperthyroidism induces a hyperdynamic cardiovascular state, which is associated with a faster heart rate, enhanced left ventricular systolic and diastolic function whereas hypothyroidism is characterized by the opposite changes. Hyperthyroidism and hypothyroidism represent opposite clinical conditions, albeit not mirror images. Recent experimental and clinical studies have suggested the involvement of ROS tissue damage under altered thyroid status. Altered-thyroid state-linked changes in heart modify their susceptibility to oxidants and the extent of the oxidative damage they suffer following oxidative challenge. Chronic increase in the cellular levels of ROS can lead to a catastrophic cycle of DNA damage, mitochondrial dysfunction, further ROS generation and cellular injury. Thus, these cellular events might play an important role in the development and progression of myocardial remodeling and heart failure in altered thyroid states (hypo- and hyper-thyroidism). The present review aims at elucidating the various signaling pathways mediated via ROS and their modulation under altered thyroid state and the possibility of antioxidant therapy. PMID:22649319

Levetiracetam mitigates doxorubicin-induced DNA and synaptic damage in neurons.

PubMed

Manchon, Jose Felix Moruno; Dabaghian, Yuri; Uzor, Ndidi-Ese; Kesler, Shelli R; Wefel, Jeffrey S; Tsvetkov, Andrey S

2016-05-11

Neurotoxicity may occur in cancer patients and survivors during or after chemotherapy. Cognitive deficits associated with neurotoxicity can be subtle or disabling and frequently include disturbances in memory, attention, executive function and processing speed. Searching for pathways altered by anti-cancer treatments in cultured primary neurons, we discovered that doxorubicin, a commonly used anti-neoplastic drug, significantly decreased neuronal survival. The drug promoted the formation of DNA double-strand breaks in primary neurons and reduced synaptic and neurite density. Pretreatment of neurons with levetiracetam, an FDA-approved anti-epileptic drug, enhanced survival of chemotherapy drug-treated neurons, reduced doxorubicin-induced formation of DNA double-strand breaks, and mitigated synaptic and neurite loss. Thus, levetiracetam might be part of a valuable new approach for mitigating synaptic damage and, perhaps, for treating cognitive disturbances in cancer patients and survivors.

Levetiracetam mitigates doxorubicin-induced DNA and synaptic damage in neurons

PubMed Central

Manchon, Jose Felix Moruno; Dabaghian, Yuri; Uzor, Ndidi-Ese; Kesler, Shelli R.; Wefel, Jeffrey S.; Tsvetkov, Andrey S.

2016-01-01

Neurotoxicity may occur in cancer patients and survivors during or after chemotherapy. Cognitive deficits associated with neurotoxicity can be subtle or disabling and frequently include disturbances in memory, attention, executive function and processing speed. Searching for pathways altered by anti-cancer treatments in cultured primary neurons, we discovered that doxorubicin, a commonly used anti-neoplastic drug, significantly decreased neuronal survival. The drug promoted the formation of DNA double-strand breaks in primary neurons and reduced synaptic and neurite density. Pretreatment of neurons with levetiracetam, an FDA-approved anti-epileptic drug, enhanced survival of chemotherapy drug-treated neurons, reduced doxorubicin-induced formation of DNA double-strand breaks, and mitigated synaptic and neurite loss. Thus, levetiracetam might be part of a valuable new approach for mitigating synaptic damage and, perhaps, for treating cognitive disturbances in cancer patients and survivors. PMID:27168474

Aldosterone and parathyroid hormone: a precarious couple for cardiovascular disease.

PubMed

Tomaschitz, Andreas; Ritz, Eberhard; Pieske, Burkert; Fahrleitner-Pammer, Astrid; Kienreich, Katharina; Horina, Jörg H; Drechsler, Christiane; März, Winfried; Ofner, Michael; Pieber, Thomas R; Pilz, Stefan

2012-04-01

Animal and human studies support a clinically relevant interaction between aldosterone and parathyroid hormone (PTH) levels and suggest an impact of the interaction on cardiovascular (CV) health. This review focuses on mechanisms behind the bidirectional interactions between aldosterone and PTH and their potential impact on the CV system. There is evidence that PTH increases the secretion of aldosterone from the adrenals directly as well as indirectly by activating the renin-angiotensin system. Upregulation of aldosterone synthesis might contribute to the higher risk of arterial hypertension and of CV damage in patients with primary hyperparathyroidism. Furthermore, parathyroidectomy is followed by decreased blood pressure levels and reduced CV morbidity as well as lower renin and aldosterone levels. In chronic heart failure, the aldosterone activity is inappropriately elevated, causing salt retention; it has been argued that the resulting calcium wasting causes secondary hyperparathyroidism. The ensuing intracellular calcium overload and oxidative stress, caused by PTH and amplified by the relative aldosterone excess, may increase the risk of CV events. In the setting of primary aldosteronism, renal and faecal calcium loss triggers increased PTH secretion which in turn aggravates aldosterone secretion and CV damage. This sequence explains why adrenalectomy and blockade of the mineralocorticoid receptor tend to decrease PTH levels in patients with primary aldosteronism. In view of the reciprocal interaction between aldosterone and PTH and the potentially ensuing CV damage, studies are urgently needed to evaluate diagnostic and therapeutic strategies addressing the interaction between the two hormones.

[Critical level of radiation damage of root apical meristem and mechanisms for its recovery in Pisum sativum L].

PubMed

Kravets, E A; Mikheev, A N; Ovsiannikova, L G; Grodzinskiĭ, D M

2011-01-01

The dose dependencies of growth and cytogenetical values have been built to determine the critical level of root apical meristem damage induced by cute irradiation in the range from 2 to 20 Gr. We have analyzed the frequencies of aberrant anaphases and the aberration distribution per cell, on the one hand, and the growth of biomass, the survival and regeneration of the root meristem, on the other hand. The critical level of damage to the stem apical meristem and root of seedlings was defined as 44-48% of aberrant anaphase. Exceeding of this level leads to the launch of suicidal program through induction of multiaberrant damages and interphase cell death. It appears that competition of clones of non-aberrant cells, the cells bearing 1 and 2 damages and multiaberrant cells plays the primary role in the mechanisms of recovery. The regeneration provides full or partial restoration of the main root apical meristem. However these local processes are insufficient to restore morphogenesis and survival of seedlings in excess of the critical level damage.

Nuclear Containment Inspection Using AN Array of Guided Wave Sensors for Damage Localization

NASA Astrophysics Data System (ADS)

Cobb, A. C.; Fisher, J. L.

2010-02-01

Nuclear power plant containments are typically both the last line of defense against the release of radioactivity to the environment and the first line of defense to protect against intrusion from external objects. As such, it is important to be able to locate any damage that would limit the integrity of the containment itself. Typically, a portion of the containment consists of a metallic pressure boundary that encloses the reactor primary circuit. It is made of thick steel plates welded together, lined with concrete and partially buried, limiting areas that can be visually inspected for corrosion damage. This study presents a strategy using low frequency (<50 kHz) guided waves to find corrosion-like damage several meters from the probe in a mock-up of the containment vessel. A magnetostrictive sensor (MsS) is scanned across the width of the vessel, acquiring waveforms at a fixed interval. A beam forming strategy is used to localize the defects. Experimental results are presented for a variety of damage configurations, demonstrating the efficacy of this technique for detecting damage smaller than the ultrasonic wavelength.

Assessment of rat optic nerve damage due to microbeam radiation therapy in the treatment of glioblastomas.

PubMed

Mohamed, A; Worobec, S; Schultke, E

2008-01-01

Glioblastomas are the most common and aggressive subtype of human primary brain tumors. Due to their uncontrolled cellular proliferation, intense invasion, and lack of apoptosis, they are extremely difficult to treat. Currently, different approaches such as surgery, chemotherapy and radiation therapy have been employed as possible treatments however thus far; these treatments are not curative. Currently, microbeam radiation therapy (MRT) is being trialed in animal models of malignant brain tumors (rats) to aid in treatment. Some of the protocols tested have been shown to significantly increase survival rates. However, due to the high x-ray doses uses in MRT, the surrounding tissue of the targeted Glioblastomas may be irreversibly damaged. In previous studies, lens damage and clouding of the cornea have been observed in microbeam exposed eyes. However, to date no studies have assessed optic nerve damage. Therefore, this study examines the potential rat optic nerve damage following exposure to microbeam radiation therapy in the treatment of Glioblastomas. Although there appears to be no significant damage to the optic nerve, slight inflammation was observed within the extra ocular muscle.

Aerothermal performance and damage tolerance of a Rene 41 metallic standoff thermal protection system at Mach 6.7

NASA Technical Reports Server (NTRS)

Avery, D. E.

1984-01-01

A flight-weight, metallic thermal protection system (TPS) model applicable to Earth-entry and hypersonic-cruise vehicles was subjected to multiple cycles of both radiant and aerothermal heating in order to evaluate its aerothermal performance, structural integrity, and damage tolerance. The TPS was designed for a maximum operating temperature of 2060 R and featured a shingled, corrugation-stiffened corrugated-skin heat shield of Rene 41, a nickel-base alloy. The model was subjected to 10 radiant heating tests and to 3 radiant preheat/aerothermal tests. Under radiant-heating conditions with a maximum surface temperature of 2050 R, the TPS performed as designed and limited the primary structure away from the support ribs to temperatures below 780 R. During the first attempt at aerothermal exposure, a failure in the panel-holder test fixture severely damaged the model. However, two radiant preheat/aerothermal tests were made with the damaged model to test its damage tolerance. During these tests, the damaged area did not enlarge; however, the rapidly increasing structural temperature measuring during these tests indicates that had the damaged area been exposed to aerodynamic heating for the entire trajectory, an aluminum burn-through would have occurred.

Detection of Damaged DNA Bases by DNA Glycosylase Enzymes†

PubMed Central

Friedman, Joshua I.; Stivers, James T.

2010-01-01

A fundamental and shared process in all forms of life is the use of DNA glycosylase enzymes to excise rare damaged bases from genomic DNA. Without such enzymes, the highly-ordered primary sequences of genes would rapidly deteriorate. Recent structural and biophysical studies are beginning to reveal a fascinating multistep mechanism for damaged base detection that begins with short-range sliding of the glycosylase along the DNA chain in a distinct conformation we refer to as the search complex (SC). Sliding is frequently punctuated by the formation of a transient “interrogation” complex (IC) where the enzyme extrahelically inspects both normal and damaged bases in an exosite pocket that is distant from the active site. When normal bases are presented in the exosite, the IC rapidly collapses back to the SC, while a damaged base will efficiently partition forward into the active site to form the catalytically competent excision complex (EC). Here we review the unique problems associated with enzymatic detection of rare damaged DNA bases in the genome, and emphasize how each complex must have specific dynamic properties that are tuned to optimize the rate and efficiency of damage site location. PMID:20469926

Assessment of Feeding Acceptance and Injury of Kerman Pistachios, Pistacia vera, by Brown Marmorated Stink Bug (Hemiptera: Pentatomidae)

PubMed Central

Kamiyama, Matthew T; Hernandez, Gabriel; Nay, Justin; Hoddle, Mark S

2017-01-01

Abstract In the United States, California (CA) is the primary commercial producer of pistachio nuts, Pistacia vera L. (Anacardiaceae). The brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an invasive and polyphagous insect pest from Asia, has established in urban areas in several pistachio-growing counties in CA. Breeding BMSB populations have not been detected in commercial pistachio acreage. However, the detection of BMSB in Kern and Fresno counties, major Kerman pistachio producing areas in CA, underscored key knowledge gaps on BMSB ecology in CA and motivated investigations on the susceptibility of pistachio nuts to BMSB feeding. Laboratory feeding trials conducted in quarantine under permit indicated that adult BMSB stylets can penetrate developing pistachio shells and associated feeding was correlated with kernel necrosis for nuts collected mid to late season (June to August 2016). Feeding damage estimates indicated that higher levels of kernel injury were associated with female BMSB when compared to feeding by male BMSB. These results suggest that there is probable risk of feeding damage to field grown pistachios from BMSB. The implications of this study for BMSB pest management in the CA pistachio system and future research directions are discussed. PMID:29117381

Assessment of Feeding Acceptance and Injury of Kerman Pistachios, Pistacia vera, by Brown Marmorated Stink Bug (Hemiptera: Pentatomidae).

PubMed

Lara, Jesús R; Kamiyama, Matthew T; Hernandez, Gabriel; Nay, Justin; Hoddle, Mark S; Gao, Yulin

2017-09-01

In the United States, California (CA) is the primary commercial producer of pistachio nuts, Pistacia vera L. (Anacardiaceae). The brown marmorated stink bug (BMSB), Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an invasive and polyphagous insect pest from Asia, has established in urban areas in several pistachio-growing counties in CA. Breeding BMSB populations have not been detected in commercial pistachio acreage. However, the detection of BMSB in Kern and Fresno counties, major Kerman pistachio producing areas in CA, underscored key knowledge gaps on BMSB ecology in CA and motivated investigations on the susceptibility of pistachio nuts to BMSB feeding. Laboratory feeding trials conducted in quarantine under permit indicated that adult BMSB stylets can penetrate developing pistachio shells and associated feeding was correlated with kernel necrosis for nuts collected mid to late season (June to August 2016). Feeding damage estimates indicated that higher levels of kernel injury were associated with female BMSB when compared to feeding by male BMSB. These results suggest that there is probable risk of feeding damage to field grown pistachios from BMSB. The implications of this study for BMSB pest management in the CA pistachio system and future research directions are discussed. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Retrofitting for watershed drainage

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

Bennett, D.B.; Heaney, J.P.

1991-09-01

Over the past 8 years, degradation in Florida's Indian River Lagoon has taken the form of fish kills, reduced viable recreational and commercial fisheries, and loss of seagrass beds. Stormwater drainage practices in the watershed have been identified as the primary culprit in the slow demise of the lagoon. Specific drainage problems include an increased volume of freshwater runoff to the estuarine receiving water and deposition of organic sediments, reduced water clarity because of increased discharge of suspended solids and tea colored' groundwater - a result of drainage-canal-induced land dewatering, and eutrophication caused by nutrient loadings. In addition, poor flushingmore » in lagoon segments makes runoff impacts even more damaging to the ecosystem. Recently, the lagoon has received national, regional, state, and local attention over its degradation and citizens' action and multi-agency efforts to restore it. To mitigate damage to the Indian River lagoon, agencies are considering alternatives such as retrofitting to reduce pollutant loads and implementing a more comprehensive watershed approach to stormwater management instead of individual controls on new development currently widely practiced. A comprehensive, long-term watershed control approach avoids unnecessary construction expenses, encourages cost-effective tradeoffs based on specific objectives, facilities performance monitoring, and accounts for cumulative impacts of continued growth in the watershed.« less

Size-dependent cytotoxicity of yttrium oxide nanoparticles on primary osteoblasts in vitro

NASA Astrophysics Data System (ADS)

Zhou, Guoqiang; Li, Yunfei; Ma, Yanyan; Liu, Zhu; Cao, Lili; Wang, Da; Liu, Sudan; Xu, Wenshi; Wang, Wenying

2016-05-01

Yttrium oxide nanoparticles are an excellent host material for the rare earth metals and have high luminescence efficiency providing a potential application in photodynamic therapy and biological imaging. In this study, the effects of yttrium oxide nanoparticles with four different sizes were investigated using primary osteoblasts in vitro. The results demonstrated that the cytotoxicity generated by yttrium oxide nanoparticles depended on the particle size, and smaller particles possessed higher toxicological effects. For the purpose to elucidate the relationship between reactive oxygen species generation and cell damage, cytomembrane integrity, intracellular reactive oxygen species level, mitochondrial membrane potential, cell apoptosis rate, and activity of caspase-3 in cells were then measured. Increased reactive oxygen species level was also observed in a size-dependent way. Thus, our data demonstrated that exposure to yttrium oxide nanoparticles resulted in a size-dependent cytotoxicity in cultured primary osteoblasts, and reactive oxygen species generation should be one possible damage pathway for the toxicological effects produced by yttrium oxide particles. The results may provide useful information for more rational applications of yttrium oxide nanoparticles in the future.

Myocardial infarction increases progressive visual field defects in well treated early primary open angle glaucoma--a prospective case control study.

PubMed

Mondal, Lakshmikanta; Baidya, Krishnapada; Choudhury, Himadri; Roy, Rupam

2013-06-01

The purpose of the study was to evaluate the progression of glaucomatous field damage in patients with stable primary open angle glaucoma after an attack of myocardial infarction. In this case control study, 62 open angle glaucoma patients were selected and regularly followed up. Among 62 patients, 9 had an attack of myocardial infarction. The intra-ocular pressure and visual field progression of both the groups (myocardial infarction versus no myocardial infarction) were analysed. Three (33.3%) out of 9 patients who had suffered from myocardial infarction showed progressive visual field loss whereas only 9 (16.9%) out of 53 patients who did not suffer from myocardial infarction, showed progressive field changes. Both the groups had stable target intra-ocular pressure between 14 and 16 mm Hg. Myocardial infarction may adversely influence the progression of primary open angle glaucoma which is suspected to result from ischaemia induced neuronal loss and only control of intraocular pressure is not the only solution. We have to look for other drugs that prevents ischaemia induced neuronal damage.

Reactivating p53 and Inducing Tumor Apoptosis (RITA) Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin.

PubMed

Wiegering, Armin; Matthes, Niels; Mühling, Bettina; Koospal, Monika; Quenzer, Anne; Peter, Stephanie; Germer, Christoph-Thomas; Linnebacher, Michael; Otto, Christoph

2017-04-01

Colorectal carcinoma (CRC) is the most common cancer of the gastrointestinal tract with frequently dysregulated intracellular signaling pathways, including p53 signaling. The mainstay of chemotherapy treatment of CRC is 5-fluorouracil (5FU) and oxaliplatin. The two anticancer drugs mediate their therapeutic effect via DNA damage-triggered signaling. The small molecule reactivating p53 and inducing tumor apoptosis (RITA) is described as an activator of wild-type and reactivator of mutant p53 function, resulting in elevated levels of p53 protein, cell growth arrest, and cell death. Additionally, it has been shown that RITA can induce DNA damage signaling. It is expected that the therapeutic benefits of 5FU and oxaliplatin can be increased by enhancing DNA damage signaling pathways. Therefore, we highlighted the antiproliferative response of RITA alone and in combination with 5FU or oxaliplatin in human CRC cells. A panel of long-term established CRC cell lines (n=9) including p53 wild-type, p53 mutant, and p53 null and primary patient-derived, low-passage cell lines (n=5) with different p53 protein status were used for this study. A substantial number of CRC cells with pronounced sensitivity to RITA (IC 50 <3.0 μmol/l) were identified within established (4/9) and primary patient-derived (2/5) CRC cell lines harboring wild-type or mutant p53 protein. Sensitivity to RITA appeared independent of p53 status and was associated with an increase in antiproliferative response to 5FU and oxaliplatin, a transcriptional increase of p53 targets p21 and NOXA, and a decrease in MYC mRNA. The effect of RITA as an inducer of DNA damage was shown by a strong elevation of phosphorylated histone variant H2A.X, which was restricted to RITA-sensitive cells. Our data underline the primary effect of RITA, inducing DNA damage, and demonstrate the differential antiproliferative effect of RITA to CRC cells independent of p53 protein status. We found a substantial number of RITA-sensitive CRC cells within both panels of established CRC cell lines and primary patient-derived CRC cell lines (6/14) that provide a rationale for combining RITA with 5FU or oxaliplatin to enhance the antiproliferative response to both chemotherapeutic agents. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Analysis and Characterization of Damage and Failure Utilizing a Generalized Composite Material Model Suitable for Use in Impact Problems

NASA Technical Reports Server (NTRS)

Goldberg, Robert K.; Carney, Kelly S.; DuBois, Paul; Khaled, Bilal; Hoffarth, Canio; Rajan, Subramaniam; Blankenhorn, Gunther

2016-01-01

A material model which incorporates several key capabilities which have been identified by the aerospace community as lacking in state-of-the art composite impact models is under development. In particular, a next generation composite impact material model, jointly developed by the FAA and NASA, is being implemented into the commercial transient dynamic finite element code LS-DYNA. The material model, which incorporates plasticity, damage, and failure, utilizes experimentally based tabulated input to define the evolution of plasticity and damage and the initiation of failure as opposed to specifying discrete input parameters (such as modulus and strength). The plasticity portion of the orthotropic, three-dimensional, macroscopic composite constitutive model is based on an extension of the Tsai-Wu composite failure model into a generalized yield function with a non-associative flow rule. For the damage model, a strain equivalent formulation is utilized to allow for the uncoupling of the deformation and damage analyses. In the damage model, a semi-coupled approach is employed where the overall damage in a particular coordinate direction is assumed to be a multiplicative combination of the damage in that direction resulting from the applied loads in the various coordinate directions. Due to the fact that the plasticity and damage models are uncoupled, test procedures and methods to both characterize the damage model and to covert the material stress-strain curves from the true (damaged) stress space to the effective (undamaged) stress space have been developed. A methodology has been developed to input the experimentally determined composite failure surface in a tabulated manner. An analytical approach is then utilized to track how close the current stress state is to the failure surface.

Use of damage surveys and field inventories to evaluate oak and sugar maple health in the northern United States

Treesearch

Randall S Morin; Christopher W. Woodall; Jim Steinman; Charles H. Perry

2009-01-01

Oak species (Quercus spp.) and sugar maple (Acer saccharum) are substantial components of the forest ecosystems in the 24-state region spanning the northern U.S. During recent decades, both damage surveys and forest inventories have documented declines of sugar maple and oak health. In order to more fully assess the status of oak and sugar maple health, we examined...

OBJECT KINETIC MONTE CARLO SIMULATIONS OF RADIATION DAMAGE IN BULK TUNGSTEN

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

Nandipati, Giridhar; Setyawan, Wahyu; Heinisch, Howard L.

2015-09-22

We used our recently developed lattice based OKMC code; KSOME [1] to carryout simulations of radiation damage in bulk W. We study the effect of dimensionality of self interstitial atom (SIA) diffusion i.e. 1D versus 3D on the defect accumulation during irradiation with a primary knock-on atom (PKA) energy of 100 keV at 300 K for the dose rates of 10-5 and 10-6 dpa/s. As expected 3D SIA diffusion significantly reduces damage accumulation due to increased probability of recombination events. In addition, dose rate, over the limited range examined here, appears to have no effect in both cases of SIAmore » diffusion.« less

Plasma induced DNA damage: Comparison with the effects of ionizing radiation

NASA Astrophysics Data System (ADS)

Lazović, S.; Maletić, D.; Leskovac, A.; Filipović, J.; Puač, N.; Malović, G.; Joksić, G.; Petrović, Z. Lj.

2014-09-01

We use human primary fibroblasts for comparing plasma and gamma rays induced DNA damage. In both cases, DNA strand breaks occur, but of fundamentally different nature. Unlike gamma exposure, contact with plasma predominantly leads to single strand breaks and base-damages, while double strand breaks are mainly consequence of the cell repair mechanisms. Different cell signaling mechanisms are detected confirming this (ataxia telangiectasia mutated - ATM and ataxia telangiectasia and Rad3 related - ATR, respectively). The effective plasma doses can be tuned to match the typical therapeutic doses of 2 Gy. Tailoring the effective dose through plasma power and duration of the treatment enables safety precautions mainly by inducing apoptosis and consequently reduced frequency of micronuclei.

Damage/fault diagnosis in an operating wind turbine under uncertainty via a vibration response Gaussian mixture random coefficient model based framework

NASA Astrophysics Data System (ADS)

Avendaño-Valencia, Luis David; Fassois, Spilios D.

2017-07-01

The study focuses on vibration response based health monitoring for an operating wind turbine, which features time-dependent dynamics under environmental and operational uncertainty. A Gaussian Mixture Model Random Coefficient (GMM-RC) model based Structural Health Monitoring framework postulated in a companion paper is adopted and assessed. The assessment is based on vibration response signals obtained from a simulated offshore 5 MW wind turbine. The non-stationarity in the vibration signals originates from the continually evolving, due to blade rotation, inertial properties, as well as the wind characteristics, while uncertainty is introduced by random variations of the wind speed within the range of 10-20 m/s. Monte Carlo simulations are performed using six distinct structural states, including the healthy state and five types of damage/fault in the tower, the blades, and the transmission, with each one of them characterized by four distinct levels. Random vibration response modeling and damage diagnosis are illustrated, along with pertinent comparisons with state-of-the-art diagnosis methods. The results demonstrate consistently good performance of the GMM-RC model based framework, offering significant performance improvements over state-of-the-art methods. Most damage types and levels are shown to be properly diagnosed using a single vibration sensor.

Scalable Algorithms for Global Scale Remote Sensing Applications

NASA Astrophysics Data System (ADS)

Vatsavai, R. R.; Bhaduri, B. L.; Singh, N.

2015-12-01

Recent decade has witnessed major changes on the Earth, for example, deforestation, varying cropping and human settlement patterns, and crippling damages due to disasters. Accurate damage assessment caused by major natural and anthropogenic disasters is becoming critical due to increases in human and economic loss. This increase in loss of life and severe damages can be attributed to the growing population, as well as human migration to the disaster prone regions of the world. Rapid assessment of these changes and dissemination of accurate information is critical for creating an effective emergency response. Change detection using high-resolution satellite images is a primary tool in assessing damages, monitoring biomass and critical infrastructures, and identifying new settlements. Existing change detection methods suffer from registration errors and often based on pixel (location) wise comparison of spectral observations from single sensor. In this paper we present a novel probabilistic change detection framework based on patch comparison and a GPU implementation that supports near real-time rapid damage exploration capability.

Lost ecosystem services as a measure of oil spill damages: a conceptual analysis of the importance of baselines.

PubMed

Kennedy, Chris J; Cheong, So-Min

2013-10-15

The assessment and quantification of damages resulting from marine oil spills is typically coordinated by NOAA, and has historically utilized Habitat Equivalency Analysis (HEA) to estimate damages. Resource economists and others have called for the damage assessment process to instead estimate injuries through the valuation of lost ecosystem services. Our conceptual analysis explores ecosystem service valuation from the perspective of "baselines," which are a fundamental component of both primary and compensatory restoration activities. In practice, baselines have been defined in ecological terms, with minimal consideration of the socioeconomic side of ecosystem service provision. We argue that, for the purposes of scaling compensatory restoration, it is more appropriate to characterize baselines in value terms, thereby integrating non-market valuation approaches from the onset of the damage assessment process. Benefits and challenges of this approach are discussed, along with guidelines for practitioners to identify circumstances in which socioeconomic variables are likely to be important for baseline characterization. Copyright © 2013 Elsevier Ltd. All rights reserved.

Neuronal and BBB damage induced by sera from patients with secondary progressive multiple sclerosis.

PubMed

Proia, Patrizia; Schiera, Gabriella; Salemi, Giuseppe; Ragonese, Paolo; Savettieri, Giovanni; Di Liegro, Italia

2009-12-01

An important component of the pathogenic process of multiple sclerosis (MS) is the blood-brain barrier (BBB) damage. We recently set an in vitro model of BBB, based on a three-cell-type co-culture system, in which rat neurons and astrocytes synergistically induce brain capillary endothelial cells to form a monolayer with permeability properties resembling those of the physiological BBB. Herein we report that the serum from patients with secondary progressive multiple sclerosis (SPMS) has a damaging effect on isolated neurons. This finding suggests that neuronal damaging in MS could be a primary event and not only secondary to myelin damage, as generally assumed. SPMS serum affects the permeability of the BBB model, as indicated by the decrease of the transendothelial electrical resistance (TEER). Moreover, as shown by both immunofluorescence and Western blot analyses, BBB breaking is accompanied by a decrease of the synthesis as well as the peripheral localization of occludin, a structural protein of the tight junctions that are responsible for BBB properties.

An altered redox balance and increased genetic instability characterize primary fibroblasts derived from xeroderma pigmentosum group A patients.

PubMed

Parlanti, Eleonora; Pietraforte, Donatella; Iorio, Egidio; Visentin, Sergio; De Nuccio, Chiara; Zijno, Andrea; D'Errico, Mariarosaria; Simonelli, Valeria; Sanchez, Massimo; Fattibene, Paola; Falchi, Mario; Dogliotti, Eugenia

2015-12-01

Xeroderma pigmentosum (XP)-A patients are characterized by increased solar skin carcinogenesis and present also neurodegeneration. XPA deficiency is associated with defective nucleotide excision repair (NER) and increased basal levels of oxidatively induced DNA damage. In this study we search for the origin of increased levels of oxidatively generated DNA lesions in XP-A cell genome and then address the question of whether increased oxidative stress might drive genetic instability. We show that XP-A human primary fibroblasts present increased levels and different types of intracellular reactive oxygen species (ROS) as compared to normal fibroblasts, with O₂₋• and H₂O₂ being the major reactive species. Moreover, XP-A cells are characterized by decreased reduced glutathione (GSH)/oxidized glutathione (GSSG) ratios as compared to normal fibroblasts. The significant increase of ROS levels and the alteration of the glutathione redox state following silencing of XPA confirmed the causal relationship between a functional XPA and the control of redox balance. Proton nuclear magnetic resonance (¹H NMR) analysis of the metabolic profile revealed a more glycolytic metabolism and higher ATP levels in XP-A than in normal primary fibroblasts. This perturbation of bioenergetics is associated with different morphology and response of mitochondria to targeted toxicants. In line with cancer susceptibility, XP-A primary fibroblasts showed increased spontaneous micronuclei (MN) frequency, a hallmark of cancer risk. The increased MN frequency was not affected by inhibition of ROS to normal levels by N-acetyl-L-cysteine. Copyright © 2015 Elsevier B.V. All rights reserved.

Multiphoton Absorption is Probably Not the Primary Threshold Damage Mechanism for Femtosecond Laser Pulse Exposures in the Retinal Pigment Epithelium

DTIC Science & Technology

2004-01-01

Tromberg, and E. Gratton, "Two-photon excited lifetime imaging of autofluorescence in cells during UTVA and NIR photostress", J. Micros. 183, pp. 197-204...1996. 4. K. Konig, Y. Liu, G. J. Sonek, M. W. Berns, and B. J. Tromberg, " Autofluorescence spectroscopy of optically trapped cells", Photochem...34, Photochem. Photobiol. 70, pp. 146-151, 1999. 10. R. D. Glickman, "Phototoxicity to the retina : Mechanisms of damage", International Journal of

Oral health considerations in anorexia and bulimia nervosa. 2. Multidisciplinary management and personalized dental care.

PubMed

Bassiouny, Mohamed A; Tweddale, Elizabeth

2017-01-01

This article outlines a comprehensive, multidisciplinary strategy for treatment of patients with anorexia and bulimia nervosa. In this approach, primary medical intervention and emergency dental care are followed by the staging of treatment phases that integrate medical care, psychotherapy, nutritional counseling, and dental management, which may encompass various treatment options for repair of damaged dentition. Emphasis is placed on prevention of further tissue damage during all phases of management and following completion of the treatment course.

Plumbrook Hypersonic Tunnel Facility Graphite Furnace Degradation Mechanisms

NASA Technical Reports Server (NTRS)

Jacobson, Nathan S.

1999-01-01

A recent rebuild revealed extensive degradation to the large graphite induction furnace in the Hypersonic Tunnel Facility (HTF). This damage to the graphite blocks and insulating felt is examined and modeled with thermochemical equilibrium codes. The primary reactions appear to be with water vapor and the nitrogen purge gas. Based on these conclusions, several changes are recommended. An inert purge gas (e.g. argon or helium) and controlling and monitoring water vapor to about 10 ppm should decrease the damage substantially.

Kidney Disease Statistics for the United States

MedlinePlus

... that a person’s kidneys are damaged and cannot filter blood the way they should. This damage can ... per 1.73 m 2 ). Dialysis: Treatment to filter wastes and water from the blood. When their ...

Ab initio and Molecular Dynamic models of displacement damage in crystalline and turbostratic graphite

NASA Astrophysics Data System (ADS)

McKenna, Alice

One of the functions of graphite is as a moderator in several nuclear reactor designs, including the Advanced Gas-cooled Reactor (AGR). In the reactor graphite is used to thermalise the neutrons produced in the fission reaction thus allowing a self-sustained reaction to occur. The graphite blocks, acting as the moderator, are constantly irradiated and consequently suffer damage. This thesis examines the types of damage caused using molecular dynamic (MD) simulations and ab intio calculations. Neutron damage starts with a primary knock-on atom (PKA), which is travelling so fast that it creates damage through electronic and thermal excitation (this is addressed with thermal spike simulations). When the PKA has lost energy the subsequent cascade is based on ballistic atomic displacement. These two types of simulations were performed on single crystal graphite and other carbon structures such as diamond and amorphous carbon as a comparison. The thermal spike in single crystal graphite produced results which varied from no defects to a small number of permanent defects in the structure. It is only at the high energy range that more damage is seen but these energies are less likely to occur in the nuclear reactor. The thermal spike does not create damage but it is possible that it can heal damaged sections of the graphite, which can be demonstrated with the motion of the defects when a thermal spike is applied. The cascade simulations create more damage than the thermal spike even though less energy is applied to the system. A new damage function is found with a threshold region that varies with the square root of energy in excess of the energy threshold. This is further broken down in to contributions from primary and subsequent knock-on atoms. The threshold displacement energy (TDE) is found to be Ed=25eV at 300K. In both these types of simulation graphite acts very differently to the other carbon structures. There are two types of polycrystalline graphite structures which simulations have been performed on. The difference between the two is at the grain boundaries with one having dangling bonds and the other one being bonded. The cascade showed the grain boundaries acting as a trap for the knock-on atoms which produces more damage compared with the single crystal. Finally the effects of turbostratic disorder on damage is considered. Density functional theory (DFT) was used to look at interstitials in (002) twist boundaries and how they act compared to AB stacked graphite. The results of these calculations show that the spiro interstitial is more stable in these grain boundaries, so at temperatures where the interstitial can migrate along the c direction they will segregate to (002) twist boundaries.

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

Livescu, Veronica; Bronkhorst, Curt Allan; Vander Wiel, Scott Alan

Many challenges exist with regard to understanding and representing complex physical processes involved with ductile damage and failure in polycrystalline metallic materials. Currently, the ability to accurately predict the macroscale ductile damage and failure response of metallic materials is lacking. Research at Los Alamos National Laboratory (LANL) is aimed at building a coupled experimental and computational methodology that supports the development of predictive damage capabilities by: capturing real distributions of microstructural features from real material and implementing them as digitally generated microstructures in damage model development; and, distilling structure-property information to link microstructural details to damage evolution under a multitudemore » of loading states.« less

Electrical Resistance of Ceramic Matrix Composites for Damage Detection and Life-Prediction

NASA Technical Reports Server (NTRS)

Smith, Craig; Morscher, Gregory N.; Xia, Zhenhai

2008-01-01

The electric resistance of woven SiC fiber reinforced SiC matrix composites were measured under tensile loading conditions. The results show that the electrical resistance is closely related to damage and that real-time information about the damage state can be obtained through monitoring of the resistance. Such self-sensing capability provides the possibility of on-board/in-situ damage detection or inspection of a component during "down time". The correlation of damage with appropriate failure mechanism can then be applied to accurate life prediction for high-temperature ceramic matrix composites.

Research on Damage Models for Continuous Fiber Composites

DTIC Science & Technology

1988-07-01

r ~.F (~ Mechanics and Materials Center TEXAS A&M UNIVERSITY College Station, Texas RESEARCH ON DAMAGE MODELS FOR CONTINUOUS FIBER COMPOSITES Final...Washington, DC 20332 11. TITLE (Include Security Clas=fication) Research on Damage Models for Continuous Fiber Composites - Final Technical Report 1...GROUP SUB-GROU ::=, COMPOsites ) continuum mechanics , ~ idamage, internal state variables V experimental mechanics, laminated composites o 19. ABSTRACT

Rapid assessment of wildfire damage using Forest Inventory data: A case in Georgia

Treesearch

Richard A. Harper; John W. Coulsten; Jeffery A. Turner

2009-01-01

The rapid assessment of damage caused by natural disasters is essential for planning the appropriate amount of disaster relief funds and public communication. Annual Forest Inventory and Analysis (FIA) data provided initial estimates of damage to timberland in a timely manner to State leaders during the 2007 Georgia Bay Complex Wildfire in southeast Georgia. FIA plots...

Advances in threat assessment and their application to forest and rangeland management—Volume 2

Treesearch

H. Michael Rauscher; Yasmeen Sands; Danny C. Lee; Jerome S. Beatty

2010-01-01

Risk is a combined statement of the probability that something of value will be damaged and some measure of the damage’s adverse effect. Wildfires burning in the uncharacteristic fuel conditions now typical throughout the Western United States can damage ecosystems and adversely affect environmental conditions. Wildfire behavior can be modified by prefire fuel...

An Account of Preliminary Landslide Damage and Losses Resulting from the February 28, 2001, Nisqually, Washington, Earthquake

USGS Publications Warehouse

Highland, Lynn M.

2003-01-01

The February 28, 2001, Nisqually, Washington, earthquake (Mw = 6.8) damaged an area of the northwestern United States that previously experienced two major historical earthquakes, in 1949 and in 1965. Preliminary estimates of direct monetary losses from damage due to earthquake-induced landslides is approximately $34.3 million. However, this figure does not include costs from damages to the elevated portion of the Alaskan Way Viaduct, a major highway through downtown Seattle, Washington that will be repaired or rebuilt, depending on the future decision of local and state authorities. There is much debate as to the cause of the damage to this viaduct with evaluations of cause ranging from earthquake shaking and liquefaction to lateral spreading to a combination of these effects. If the viaduct is included in the costs, the losses increase to $500+ million (if it is repaired) or to more than $1+ billion (if it is replaced). Preliminary estimate of losses due to all causes of earthquake damage is approximately $2 billion, which includes temporary repairs to the Alaskan Way Viaduct. These preliminary dollar figures will no doubt increase when plans and decisions regarding the Viaduct are completed.

Classification of damage in structural systems using time series analysis and supervised and unsupervised pattern recognition techniques

NASA Astrophysics Data System (ADS)

Omenzetter, Piotr; de Lautour, Oliver R.

2010-04-01

Developed for studying long, periodic records of various measured quantities, time series analysis methods are inherently suited and offer interesting possibilities for Structural Health Monitoring (SHM) applications. However, their use in SHM can still be regarded as an emerging application and deserves more studies. In this research, Autoregressive (AR) models were used to fit experimental acceleration time histories from two experimental structural systems, a 3- storey bookshelf-type laboratory structure and the ASCE Phase II SHM Benchmark Structure, in healthy and several damaged states. The coefficients of the AR models were chosen as damage sensitive features. Preliminary visual inspection of the large, multidimensional sets of AR coefficients to check the presence of clusters corresponding to different damage severities was achieved using Sammon mapping - an efficient nonlinear data compression technique. Systematic classification of damage into states based on the analysis of the AR coefficients was achieved using two supervised classification techniques: Nearest Neighbor Classification (NNC) and Learning Vector Quantization (LVQ), and one unsupervised technique: Self-organizing Maps (SOM). This paper discusses the performance of AR coefficients as damage sensitive features and compares the efficiency of the three classification techniques using experimental data.

Cumulative Damage Model for Advanced Composite Materials.

DTIC Science & Technology

1984-03-09

Masters, J.L., "Investigation of Characteristic Damage States in Composites Laminat -s," ASME Paper No. 79-WA-AERO-4, 1978. [26] Jivinall, R.C., "Stress...AD-A144 84e CUMULATIVE DAMAGE MODEL FOR RDVRNCED COMPOSITE 1/2 MATERIRLS(U) DYNA EAST CORP PHILADELPHIA PA P C CHOU ET AL. 09 MAR 84 RFWRL-TR-84-4084...MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STANDARDS- 1963-A AFWAL-TR-84-4004 •S CUMULATIVE DAMAGE MODEL FOR ADVANCED COMPOSITE MATERIALS PHASE II 0

Quantitative nondestructive evaluation of materials and structures

NASA Technical Reports Server (NTRS)

Smith, Barry T.

1991-01-01

An experimental investigation was undertaken to quantify damage tolerance and resistance in composite materials impacted using the drop-weight method. Tests were conducted on laminates of several different carbon-fiber composite systems, such as epoxies, modified epoxies, and amorphous and semicrystalline thermoplastics. Impacted composite specimens were examined using destructive and non-destructive techniques to establish the characteristic damage states. Specifically, optical microscopy, ultrasonic, and scanning electron microscopy techniques were used to identify impact induced damage mechanisms. Damage propagation during post impact compression was also studied.

[Therapeutic principles of bronchopulmonary infections in the aged].

PubMed

Kummer, F

1983-05-01

Airways and lungs are equipped with a highly effective defense mechanism. These can bei found damaged in the aged: Cough is weaker, mucociliary clearance and mucous production are irregular. This damage can bei caused and increased by smoking, recurrent infection, and some sorts of air pollution (SO2). We call it a primary infection, when the organ has been intact as well as the general condition (immune defense etc), and where the causative agent is a virus or virus-like organism. A secondary infection is conditioned by previous disease, and when the causative agents are bacilli. Finally, a tertiary infection is dependent on a defense failure of the body and on opportunistic organisms. For elderly patients, secondary infections outweight the others (recurrent purulent bronchitits). However, tertiary infections must also bei considered in bedridden or post-operative patients or in those with metabolic disease. Finally, pneumonia in the aged must be differentiated in terms of underlying carcinoma, infarction, aspiration and tuberculosis. Therapy of primary (viral)infection consists mainly in prophylaxis of bacterial secondary infection. The choice of drug, dosage and duration of treatment depends on the degree of previous damage to the organ, of complications and status of the whole body and it's defense mechanisms.

Chemotherapeutic potential of quercetin on human bladder cancer cells.

PubMed

Oršolić, Nada; Karač, Ivo; Sirovina, Damir; Kukolj, Marina; Kunštić, Martina; Gajski, Goran; Garaj-Vrhovac, Vera; Štajcar, Damir

2016-07-28

In an effort to improve local bladder cancer control, we investigated the cytotoxic and genotoxic effects of quercetin on human bladder cancer T24 cells. The cytotoxic effect of quercetin against T24 cells was examined by MTT test, clonogenic assay as well as DNA damaging effect by comet assay. In addition, the cytotoxic effect of quercetin on the primary culture of papillary urothelial carcinoma (PUC), histopathological stage T1 of low- or high-grade tumours, was investigated. Our analysis demonstrated a high correlation between reduced number of colony and cell viability and an increase in DNA damage of T24 cells incubated with quercetin at doses of 1 and 50 µM during short term incubation (2 h). At all exposure times (24, 48 and 72 h), the efficacy of quercetin, administered at a 10× higher dose compared to T24 cells, was statistically significant (P < 0.05) for the primary culture of PUC. In conclusion, our study suggests that quercetin could inhibit cell proliferation and colony formation of human bladder cancer cells by inducing DNA damage and that quercetin may be an effective chemopreventive and chemotherapeutic agent for papillary urothelial bladder cancer after transurethral resection.

44 CFR 201.4 - Standard State Mitigation Plans.

Code of Federal Regulations, 2014 CFR

2014-10-01

... State owned or operated buildings, infrastructure, and critical facilities located in the identified... vulnerable to damage and loss associated with hazard events. State owned or operated critical facilities...

44 CFR 201.4 - Standard State Mitigation Plans.

Code of Federal Regulations, 2012 CFR

2012-10-01

... State owned or operated buildings, infrastructure, and critical facilities located in the identified... vulnerable to damage and loss associated with hazard events. State owned or operated critical facilities...

Behavioral pattern identification for structural health monitoring in complex systems

NASA Astrophysics Data System (ADS)

Gupta, Shalabh

Estimation of structural damage and quantification of structural integrity are critical for safe and reliable operation of human-engineered complex systems, such as electromechanical, thermofluid, and petrochemical systems. Damage due to fatigue crack is one of the most commonly encountered sources of structural degradation in mechanical systems. Early detection of fatigue damage is essential because the resulting structural degradation could potentially cause catastrophic failures, leading to loss of expensive equipment and human life. Therefore, for reliable operation and enhanced availability, it is necessary to develop capabilities for prognosis and estimation of impending failures, such as the onset of wide-spread fatigue crack damage in mechanical structures. This dissertation presents information-based online sensing of fatigue damage using the analytical tools of symbolic time series analysis ( STSA). Anomaly detection using STSA is a pattern recognition method that has been recently developed based upon a fixed-structure, fixed-order Markov chain. The analysis procedure is built upon the principles of Symbolic Dynamics, Information Theory and Statistical Pattern Recognition. The dissertation demonstrates real-time fatigue damage monitoring based on time series data of ultrasonic signals. Statistical pattern changes are measured using STSA to monitor the evolution of fatigue damage. Real-time anomaly detection is presented as a solution to the forward (analysis) problem and the inverse (synthesis) problem. (1) the forward problem - The primary objective of the forward problem is identification of the statistical changes in the time series data of ultrasonic signals due to gradual evolution of fatigue damage. (2) the inverse problem - The objective of the inverse problem is to infer the anomalies from the observed time series data in real time based on the statistical information generated during the forward problem. A computer-controlled special-purpose fatigue test apparatus, equipped with multiple sensing devices (e.g., ultrasonics and optical microscope) for damage analysis, has been used to experimentally validate the STSA method for early detection of anomalous behavior. The sensor information is integrated with a software module consisting of the STSA algorithm for real-time monitoring of fatigue damage. Experiments have been conducted under different loading conditions on specimens constructed from the ductile aluminium alloy 7075 - T6. The dissertation has also investigated the application of the STSA method for early detection of anomalies in other engineering disciplines. Two primary applications include combustion instability in a generic thermal pulse combustor model and whirling phenomenon in a typical misaligned shaft.

Ozone damage detection in cantaloupe plants

NASA Technical Reports Server (NTRS)

Gausman, H. W.; Escobar, D. E.; Rodriguez, R. R.; Thomas, C. E.; Bowen, R. L.

1978-01-01

Ozone causes up to 90 percent of air pollution injury to vegetation in the United States; excess ozone affects plant growth and development and can cause undetected decrease in yields. Laboratory and field reflectance measurements showed that ozone-damaged cantaloupe (Cucumis melo L.) leaves had lower water contents and higher reflectance than did nondamaged leaves. Cantaloupe plants which were lightly, severely, and very severely ozone-damaged were distinguishable from nondamaged plants by reflectance measurements in the 1.35- to 2.5 micron near-infrared water absorption waveband. Ozone-damaged leaf areas were detected photographically 16 h before the damage was visible. Sensors are available for use with aircraft and spacecraft that possibly could be used routinely to detect ozone-damaged crops.

Damages from the 20 September earthquakes near Klamath Falls, Oregon

USGS Publications Warehouse

Dewey, J.W.

1993-01-01

Most of the damage resulting from the earthquakes was reported from Klamath Falls, approximately 20 km from the source region of earthquakes. As has commonly been the case with earthquakes in other parts of the United States, the degree of damage was highly uneven in Klamath Falls. Most of the town escaped with little damage to buildings or building contents. Losses were concentrated in the downtown area, but even there most of the buildings were not damaged. The unevenness of damage in earthquakes results primarily from large differences in the seismic resistance of individual buildings and differences in the seismic response due to different soil conditions and geology beneath buildings. 

Role of damage control enterostomy in management of children with peritonitis from acute intestinal disease.

PubMed

Ameh, Emmanuel A; Ayeni, Michael A; Kache, Stephen A; Mshelbwala, Philip M

2013-01-01

Intestinal anastomosis in severely ill children with peritonitis from intestinal perforation, intestinal gangrene or anastomotic dehiscence (acute intestinal disease) is associated with high morbidity and mortality. Enterostomy as a damage control measure may be an option to minimize the high morbidity and mortality. This report evaluates the role of damage control enterostomy in the treatment of these patients. A retrospective review of 52 children with acute intestinal disease who had enterostomy as a damage control measure in 12 years. There were 34 (65.4%) boys and 18 (34.6%) girls aged 3 days-13 years (median 9 months), comprising 27 (51.9%) neonates and infants and 25 (48.1%) older children. The primary indication for enterostomy in neonates and infants was intestinal gangrene 25 (92.6%) and perforated typhoid ileitis 22 (88%) in older children. Enterostomy was performed as the initial surgery in 33 (63.5%) patients and as a salvage procedure following anastomotic dehiscence in 19 (36.5%) patients. Enterostomy-related complications occurred in 19 (36.5%) patients, including 11 (21.2%) patients with skin excoriations and eight (15.4%) with hypokalaemia. There were four (7.7%) deaths (aged 19 days, 3 months, 3½ years and 10 years, respectively) directly related to the enterostomy, from hypokalaemia at 4, 12, 20 and 28 days postoperatively, respectively. Twenty other patients died shortly after surgery from their primary disease. Twenty of 28 surviving patients have had their enterostomy closed without complications, while eight are awaiting enterostomy closure. Damage-control enterostomy is useful in management of severely ill children with intestinal perforation or gangrene. Careful and meticulous attention to fluid and electrolyte balance, and stoma care, especially in the first several days following surgery, are important in preventing morbidity and mortality.

Evolution of ischemic damage and behavioural deficit over 6 months after MCAo in the rat: Selecting the optimal outcomes and statistical power for multi-centre preclinical trials

PubMed Central

Churilov, Leonid; Sidon, T. Kate; Aleksoska, Elena; Cox, Susan F.; Macleod, Malcolm R.; Howells, David W.

2017-01-01

Key disparities between the timing and methods of assessment in animal stroke studies and clinical trial may be part of the reason for the failure to translate promising findings. This study investigates the development of ischemic damage after thread occlusion MCAo in the rat, using histological and behavioural outcomes. Using the adhesive removal test we investigate the longevity of behavioural deficit after ischemic stroke in rats, and examine the practicality of using such measures as the primary outcome for future studies. Ischemic stroke was induced in 132 Spontaneously Hypertensive Rats which were assessed for behavioural and histological deficits at 1, 3, 7, 14, 21, 28 days, 12 and 24 weeks (n>11 per timepoint). The basic behavioural score confirmed induction of stroke, with deficits specific to stroke animals. Within 7 days, these deficits resolved in 50% of animals. The adhesive removal test revealed contralateral neglect for up to 6 months following stroke. Sample size calculations to facilitate the use of this test as the primary experimental outcome resulted in cohort sizes much larger than are the norm for experimental studies. Histological damage progressed from a necrotic infarct to a hypercellular area that cleared to leave a fluid filled cavity. Whilst absolute volume of damage changed over time, when corrected for changes in hemispheric volume, an equivalent area of damage was lost at all timepoints. Using behavioural measures at chronic timepoints presents significant challenges to the basic science community in terms of the large number of animals required and the practicalities associated with this. Multicentre preclinical randomised controlled trials as advocated by the MultiPART consortium may be the only practical way to deal with this issue. PMID:28182727

Time to first take-back operation predicts successful primary fascial closure in patients undergoing damage control laparotomy.

PubMed

Pommerening, Matthew J; DuBose, Joseph J; Zielinski, Martin D; Phelan, Herb A; Scalea, Thomas M; Inaba, Kenji; Velmahos, George C; Whelan, James F; Wade, Charles E; Holcomb, John B; Cotton, Bryan A

2014-08-01

Failure to achieve primary fascial closure (PFC) after damage control laparotomy is costly and carries great morbidity. We hypothesized that time from the initial laparotomy to the first take-back operation would be predictive of successful PFC. Trauma patients managed with open abdominal techniques after damage control laparotomy were prospectively followed at 14 Level 1 trauma centers during a 2-year period. Time to the first take-back was evaluated as a predictor of PFC using hierarchical multivariate logistic regression analysis. A total of 499 patients underwent damage control laparotomy and were included in this analysis. PFC was achieved in 327 (65.5%) patients. Median time to the first take-back operation was 36 hours (interquartile range 24-48). After we adjusted for patient demographics, resuscitation volumes, and operative characteristics, increasing time to the first take-back was associated with a decreased likelihood of PFC. Specifically, each hour delay in return to the operating room (24 hours after initial laparotomy) was associated with a 1.1% decrease in the odds of PFC (odds ratio 0.989; 95% confidence interval 0.978-0.999; P = .045). In addition, there was a trend towards increased intra-abdominal complications in patients returning after 48 hours (odds ratio 1.80; 95% confidence interval 1.00-3.25; P = .05). Data from this prospective, multicenter study demonstrate that delays in returning to the operating room after damage control laparotomy are associated with reductions in PFC. These findings suggest that emphasis should be placed on returning to the operating room within 24 hours after the initial laparotomy if possible (and no later than 48 hours). Copyright © 2014 Mosby, Inc. All rights reserved.

Rapamycin (sirolimus) protects against hypoxic damage in primary heart cultures via Na+/Ca2+ exchanger activation.

PubMed

El-Ani, Dalia; Stav, Hagit; Guetta, Victor; Arad, Michael; Shainberg, Asher

2011-07-04

Rapamycin (sirolimus) is an antibiotic that inhibits protein synthesis through mammalian targeting of rapamycin (mTOR) signaling, and is used as an immunosuppressant in the treatment of organ rejection in transplant recipients. Rapamycin confers preconditioning-like protection against ischemic-reperfusion injury in isolated mouse heart cultures. Our aim was to further define the role of rapamycin in intracellular Ca(2+) homeostasis and to investigate the mechanism by which rapamycin protects cardiomyocytes from hypoxic damage. We demonstrate here that rapamycin protects rat heart cultures from hypoxic-reoxygenation (H/R) damage, as revealed by assays of lactate dehydrogenase (LDH) and creatine kinase (CK) leakage to the medium, by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) measurements, and desmin immunostaining. As a result of hypoxia, intracellular calcium levels ([Ca(2+)](i)) were elevated. However, treatment of heart cultures with rapamycin during hypoxia attenuated the increase of [Ca(2+)](i). Rapamycin also attenuated (45)Ca(2+) uptake into the sarcoplasmic reticulum (SR) of skinned heart cultures in a dose- and time-dependent manner. KB-R7943, which inhibits the "reverse" mode of Na(+)/Ca(2+) exchanger (NCX), protected heart cultures from H/R damage with or without the addition of rapamycin. Rapamycin decreased [Ca(2+)](i) following its elevation by extracellular Ca(2+) ([Ca(2+)](o)) influx, thapsigargin treatment, or depolarization with KCl. We suggest that rapamycin induces cardioprotection against hypoxic/reoxygenation damage in primary heart cultures by stimulating NCX to extrude Ca(2+) outside the cardiomyocytes. According to our findings, rapamycin preserves Ca(2+) homeostasis and prevents Ca(2+) overload via extrusion of Ca(2+) surplus outside the sarcolemma, thereby protecting the cells from hypoxic stress. Copyright © 2011 Elsevier Inc. All rights reserved.

High throughput DNA damage quantification of human tissue with home-based collection device

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

Costes, Sylvain V.; Tang, Jonathan; Yannone, Steven M.

Kits, methods and systems for providing a service to provide a subject with information regarding the state of a subject's DNA damage. Collection, processing and analysis of samples are also described.

Earthquakes, May-June 1991

USGS Publications Warehouse

Person, W.J.

1992-01-01

In the United States, a magnitude 5.8 earthquake in southern California on June 28 killed two people and caused considerable damage. Strong earthquakes hit Alaska on May 1 and May 30; the May 1 earthquake caused some minor damage. 

Dynamic maps of UV damage formation and repair for the human genome

PubMed Central

Hu, Jinchuan; Adebali, Ogun; Adar, Sheera; Sancar, Aziz

2017-01-01

Formation and repair of UV-induced DNA damage in human cells are affected by cellular context. To study factors influencing damage formation and repair genome-wide, we developed a highly sensitive single-nucleotide resolution damage mapping method [high-sensitivity damage sequencing (HS–Damage-seq)]. Damage maps of both cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts [(6-4)PPs] from UV-irradiated cellular and naked DNA revealed that the effect of transcription factor binding on bulky adducts formation varies, depending on the specific transcription factor, damage type, and strand. We also generated time-resolved UV damage maps of both CPDs and (6-4)PPs by HS–Damage-seq and compared them to the complementary repair maps of the human genome obtained by excision repair sequencing to gain insight into factors that affect UV-induced DNA damage and repair and ultimately UV carcinogenesis. The combination of the two methods revealed that, whereas UV-induced damage is virtually uniform throughout the genome, repair is affected by chromatin states, transcription, and transcription factor binding, in a manner that depends on the type of DNA damage. PMID:28607063

Dynamic maps of UV damage formation and repair for the human genome.

PubMed

Hu, Jinchuan; Adebali, Ogun; Adar, Sheera; Sancar, Aziz

2017-06-27

Formation and repair of UV-induced DNA damage in human cells are affected by cellular context. To study factors influencing damage formation and repair genome-wide, we developed a highly sensitive single-nucleotide resolution damage mapping method [high-sensitivity damage sequencing (HS-Damage-seq)]. Damage maps of both cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4) photoproducts [(6-4)PPs] from UV-irradiated cellular and naked DNA revealed that the effect of transcription factor binding on bulky adducts formation varies, depending on the specific transcription factor, damage type, and strand. We also generated time-resolved UV damage maps of both CPDs and (6-4)PPs by HS-Damage-seq and compared them to the complementary repair maps of the human genome obtained by excision repair sequencing to gain insight into factors that affect UV-induced DNA damage and repair and ultimately UV carcinogenesis. The combination of the two methods revealed that, whereas UV-induced damage is virtually uniform throughout the genome, repair is affected by chromatin states, transcription, and transcription factor binding, in a manner that depends on the type of DNA damage.

Heat-mediated reduction of apoptosis in UVB-damaged keratinocytes in vitro and in human skin ex vivo.

PubMed

Calapre, Leslie; Gray, Elin S; Kurdykowski, Sandrine; David, Anthony; Hart, Prue; Descargues, Pascal; Ziman, Mel

2016-05-26

UV radiation induces significant DNA damage in keratinocytes and is a known risk factor for skin carcinogenesis. However, it has been reported previously that repeated and simultaneous exposure to UV and heat stress increases the rate of cutaneous tumour formation in mice. Since constant exposure to high temperatures and UV are often experienced in the environment, the effects of exposure to UV and heat needs to be clearly addressed in human epidermal cells. In this study, we determined the effects of repeated UVB exposure 1 kJ/m(2) followed by heat (39 °C) to human keratinocytes. Normal human ex vivo skin models and primary keratinocytes (NHEK) were exposed once a day to UVB and/or heat stress for four consecutive days. Cells were then assessed for changes in proliferation, apoptosis and gene expression at 2 days post-exposure, to determine the cumulative and persistent effects of UV and/or heat in skin keratinocytes. Using ex vivo skin models and primary keratinocytes in vitro, we showed that UVB plus heat treated keratinocytes exhibit persistent DNA damage, as observed with UVB alone. However, we found that apoptosis was significantly reduced in UVB plus heat treated samples. Immunohistochemical and whole genome transcription analysis showed that multiple UVB plus heat exposures induced inactivation of the p53-mediated stress response. Furthermore, we demonstrated that repeated exposure to UV plus heat induced SIRT1 expression and a decrease in acetylated p53 in keratinocytes, which is consistent with the significant downregulation of p53-regulated pro-apoptotic and DNA damage repair genes in these cells. Our results suggest that UVB-induced p53-mediated cell cycle arrest and apoptosis are reduced in the presence of heat stress, leading to increased survival of DNA damaged cells. Thus, exposure to UVB and heat stress may act synergistically to allow survival of damaged cells, which could have implications for initiation skin carcinogenesis.

Numerical study on static component generation from the primary Lamb waves propagating in a plate with nonlinearity

NASA Astrophysics Data System (ADS)

Wan, Xiang; Tse, Peter W.; Zhang, Xuhui; Xu, Guanghua; Zhang, Qing; Fan, Hongwei; Mao, Qinghua; Dong, Ming; Wang, Chuanwei; Ma, Hongwei

2018-04-01

Under the discipline of nonlinear ultrasonics, in addition to second harmonic generation, static component generation is another frequently used nonlinear ultrasonic behavior in non-destructive testing (NDT) and structural health monitoring (SHM) communities. However, most previous studies on static component generation are mainly based on using longitudinal waves. It is desirable to extend static component generation from primary longitudinal waves to primary Lamb waves. In this paper, static component generation from the primary Lamb waves is studied. Two major issues are numerically investigated. First, the mode of static displacement component generated from different primary Lamb wave modes is identified. Second, cumulative effect of static displacement component from different primary Lamb wave modes is also discussed. Our study results show that the static component wave packets generated from the primary S0, A0 and S1 modes share the almost same group velocity equal to the phase velocity of S0 mode tending to zero frequency c plate . The finding indicates that whether the primary mode is S0, A0 or S1, the static components generated from these primary modes always share the nature of S0 mode. This conclusion is also verified by the displacement filed of these static components that the horizontal displacement field is almost uniform and the vertical displacement filed is antisymmetric across the thickness of the plate. The uniform distribution of horizontal displacement filed enables the static component, regardless of the primary Lamb modes, to be a promising technique for evaluating microstructural damages buried in the interior of a structure. Our study also illustrates that the static components are cumulative regardless of whether the phase velocity of the primary and secondary waves is matched or not. This observation indicates that the static component overcomes the limitations of the traditional nonlinear Lamb waves satisfying phase velocity matching condition to achieve cumulative second harmonic generation. This nature also enables the primary Lamb waves excited at a low center frequency to generate static component used for inspecting large-scale structures with micro-scale damages.

Histone H3 K79 methylation states play distinct roles in UV-induced sister chromatid exchange and cell cycle checkpoint arrest in Saccharomyces cerevisiae

PubMed Central

Rossodivita, Alyssa A.; Boudoures, Anna L.; Mecoli, Jonathan P.; Steenkiste, Elizabeth M.; Karl, Andrea L.; Vines, Eudora M.; Cole, Arron M.; Ansbro, Megan R.; Thompson, Jeffrey S.

2014-01-01

Histone post-translational modifications have been shown to contribute to DNA damage repair. Prior studies have suggested that specific H3K79 methylation states play distinct roles in the response to UV-induced DNA damage. To evaluate these observations, we examined the effect of altered H3K79 methylation patterns on UV-induced G1/S checkpoint response and sister chromatid exchange (SCE). We found that the di- and trimethylated states both contribute to activation of the G1/S checkpoint to varying degrees, depending on the synchronization method, although methylation is not required for checkpoint in response to high levels of UV damage. In contrast, UV-induced SCE is largely a product of the trimethylated state, which influences the usage of gene conversion versus popout mechanisms. Regulation of H3K79 methylation by H2BK123 ubiquitylation is important for both checkpoint function and SCE. H3K79 methylation is not required for the repair of double-stranded breaks caused by transient HO endonuclease expression, but does play a modest role in survival from continuous exposure. The overall results provide evidence for the participation of H3K79 methylation in UV-induced recombination repair and checkpoint activation, and further indicate that the di- and trimethylation states play distinct roles in these DNA damage response pathways. PMID:24748660

Reproduction Does Not Adversely Affect Liver Mitochondrial Respiratory Function but Results in Lipid Peroxidation and Increased Antioxidants in House Mice.

PubMed

Mowry, Annelise V; Kavazis, Andreas N; Sirman, Aubrey E; Potts, Wayne K; Hood, Wendy R

2016-01-01

Reproduction is thought to come at a cost to longevity. Based on the assumption that increased energy expenditure during reproduction is associated with increased free-radical production by mitochondria, oxidative damage has been suggested to drive this trade-off. We examined the impact of reproduction on liver mitochondrial function by utilizing post-reproductive and non-reproductive house mice (Mus musculus) living under semi-natural conditions. The age-matched post-reproductive and non-reproductive groups were compared after the reproductive females returned to a non-reproductive state, so that both groups were in the same physiological state at the time the liver was collected. Despite increased oxidative damage (p = 0.05) and elevated CuZnSOD (p = 0.002) and catalase (p = 0.04) protein levels, reproduction had no negative impacts on the respiratory function of liver mitochondria. Specifically, in a post-reproductive, maintenance state the mitochondrial coupling (i.e., respiratory control ratio) of mouse livers show no negative impacts of reproduction. In fact, there was a trend (p = 0.059) to suggest increased maximal oxygen consumption by liver mitochondria during the ADP stimulated state (i.e., state 3) in post-reproduction. These findings suggest that oxidative damage may not impair mitochondrial respiratory function and question the role of mitochondria in the trade-off between reproduction and longevity. In addition, the findings highlight the importance of quantifying the respiratory function of mitochondria in addition to measuring oxidative damage.

Alternative Interventions to Prevent Oxidative Damage following Ischemia/Reperfusion

PubMed Central

Rodríguez-Lara, Simón Quetzalcoatl; Ramírez-Lizardo, Ernesto Javier; Totsuka-Sutto, Sylvia Elena; Castillo-Romero, Araceli; García-Cobián, Teresa Arcelia

2016-01-01

Ischemia/reperfusion (I/R) lesions are a phenomenon that occurs in multiple pathological states and results in a series of events that end in irreparable damage that severely affects the recovery and health of patients. The principal therapeutic approaches include preconditioning, postconditioning, and remote ischemic preconditioning, which when used separately do not have a great impact on patient mortality or prognosis. Oxidative stress is known to contribute to the damage caused by I/R; however, there are no pharmacological approaches to limit or prevent this. Here, we explain the relationship between I/R and the oxidative stress process and describe some pharmacological options that may target oxidative stress-states. PMID:28116037

Axisymmetric thermoviscoelastoplastic state of thin laminated shells made of a damageable material

NASA Astrophysics Data System (ADS)

Galishin, A. Z.

2008-04-01

A technique for the determination of the axisymmetric thermoviscoelastoplastic state of laminated thin shells made of a damageable material is developed. The technique is based on the kinematic equations of the theory of thin shells that account for transverse shear strains. The thermoviscoplastic equations, which describe the deformation of a shell element along paths of small curvature, are used as the constitutive equations. The equivalent stress that appears in the kinetic equations of damage and creep is determined from a failure criterion that accounts for the stress mode. The thermoviscoplastic deformation of a two-layer shell that models an element of a rocket engine nozzle is considered as an example

Perspectives: Using Results from HRSA's Health Workforce Simulation Model to Examine the Geography of Primary Care.

PubMed

Streeter, Robin A; Zangaro, George A; Chattopadhyay, Arpita

2017-02-01

Inform health planning and policy discussions by describing Health Resources and Services Administration's (HRSA's) Health Workforce Simulation Model (HWSM) and examining the HWSM's 2025 supply and demand projections for primary care physicians, nurse practitioners (NPs), and physician assistants (PAs). HRSA's recently published projections for primary care providers derive from an integrated microsimulation model that estimates health workforce supply and demand at national, regional, and state levels. Thirty-seven states are projected to have shortages of primary care physicians in 2025, and nine states are projected to have shortages of both primary care physicians and PAs. While no state is projected to have a 2025 shortage of primary care NPs, many states are expected to have only a small surplus. Primary care physician shortages are projected for all parts of the United States, while primary care PA shortages are generally confined to Midwestern and Southern states. No state is projected to have shortages of all three provider types. Projected shortages must be considered in the context of baseline assumptions regarding current supply, demand, provider-service ratios, and other factors. Still, these findings suggest geographies with possible primary care workforce shortages in 2025 and offer opportunities for targeting efforts to enhance workforce flexibility. © Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Predicting long-term renal damage in children with vesicoureteral reflux under conservative initial management: 205 cases in a tertiary referral center.

PubMed

Alvarez, Natalia; Alvira, Reyes Delgado; Ruiz, Yurema Gonzalez; Atuan, Rafael Fernandez; Hinojosa, Alexander Siles; Heras, Miguel Angel Rihuete; Roldan, Marisa Justa; Romero, Jesus Gracia

2018-01-01

Vesicoureteral reflux (VUR) is one of the most common ailments in children. Evidence-based guidelines recommend conservative treatment in children with VUR, followed by endoscopic surgery in those with breakthrough febrile urinary tract infections (UTIs). Despite this fact, the management of VUR is still controversial. Our objective is to evaluate the conservative strategy in children with primary VUR in terms of renal function and scarring, and identify factors associated with poor prognosis in those children. A retrospective study was carried out in a tertiary center in children with primary VUR under conservative strategy treatment from 1989 to 2015. Data extracted included age of presentation, family and prenatal backgrounds, radiographic evaluation including ultrasound (US), dimercaptosuccinic acid (DMSA) scans and voiding cystourethrogram (VCUG). The SPSS program was used for statistical analysis. Two-hundred and five patients were diagnosed and followed a conservative therapy scheme (49.8% males, 50.2% females) after febrile UTI (73.17%) or prenatal diagnosis (26.83%). VCUG showed 53.20% of low-moderate VUR grade, 46.80% high VUR grade. Renal damage was present at diagnosis in 40.89%. Mean follow-up reakthrough recurrent febrile UTIs and underwent surgery. Conservative therapy was followed in 189 patients. Renal scarring or decreased kidney function were shown in 15.12% respectively. Renal damage was identified as a risk factor for poor prognosis (p-value <0.005) only for renal function deterioration. Patients with high-grade VUR required surgery in a significantly greater proportion (p <0.005) due to recurrent febrile UTIs. Conservative strategy is a feasible treatment for primary VUR in children. The majority of cases could be managed conservatively with good outcomes after long-term follow-up. Decreased renal function is more frequent in patients with high-grade VUR. Renal damage at diagnosis increases the risk for surgical treatment.

Strengthening the weak link: Built Environment modelling for loss analysis

NASA Astrophysics Data System (ADS)

Millinship, I.

2012-04-01

Methods to analyse insured losses from a range of natural perils, including pricing by primary insurers and catastrophe modelling by reinsurers, typically lack sufficient exposure information. Understanding the hazard intensity in terms of spatial severity and frequency is only the first step towards quantifying the risk of a catastrophic event. For any given event we need to know: Are any structures affected? What type of buildings are they? How much damaged occurred? How much will the repairs cost? To achieve this, detailed exposure information is required to assess the likely damage and to effectively calculate the resultant loss. Modelling exposures in the Built Environment therefore plays as important a role in understanding re/insurance risk as characterising the physical hazard. Across both primary insurance books and aggregated reinsurance portfolios, the location of a property (a risk) and its monetary value is typically known. Exactly what that risk is in terms of detailed property descriptors including structure type and rebuild cost - and therefore its vulnerability to loss - is often omitted. This data deficiency is a primary source of variations between modelled losses and the actual claims value. Built Environment models are therefore required at a high resolution to describe building attributes that relate vulnerability to property damage. However, national-scale household-level datasets are often not computationally practical in catastrophe models and data must be aggregated. In order to provide more accurate risk analysis, we have developed and applied a methodology for Built Environment modelling for incorporation into a range of re/insurance applications, including operational models for different international regions and different perils and covering residential, commercial and industry exposures. Illustrated examples are presented, including exposure modelling suitable for aggregated reinsurance analysis for the UK and bespoke high resolution modelling for industrial sites in Germany. A range of attributes are included following detailed claims analysis and engineering research with property type, age and condition identified as important differentiators of damage from flood, wind and freeze events.

Effect of strain field on displacement cascade in tungsten studied by molecular dynamics simulation

NASA Astrophysics Data System (ADS)

Wang, D.; Gao, N.; Wang, Z. G.; Gao, X.; He, W. H.; Cui, M. H.; Pang, L. L.; Zhu, Y. B.

2016-10-01

Using atomistic methods, the coupling effect of strain field and displacement cascade in body-centered cubic (BCC) tungsten is directly simulated by molecular dynamics (MD) simulations at different temperatures. The values of the hydrostatic and uniaxial (parallel or perpendicular to primary knock-on atom (PKA) direction) strains are from -2% to 2% and the temperature is from 100 to 1000 K. Because of the annealing effect, the influence of strain on radiation damage at low temperature has been proved to be more significant than that at high temperature. When the cascade proceeds under the hydrostatic strain, the Frenkel Pair (FP) production, the fraction of defect in cluster and the average size of the defect cluster, all increase at tensile state and decrease at compressive state. When the cascade is under uniaxial strain, the effect of strain parallel to PKA direction is less than the effect of hydrostatic strain, while the effect of strain perpendicular to PKA direction can be negligible. Under the uniaxial strain along <1 1 1> direction, the SIA and SIA cluster is observed to orientate along the strain direction at tensile state and the uniaxial compressive strain with direction perpendicular to <1 1 1> has led to the similar preferred nucleation. All these results indicate that under irradiation, the tensile state should be avoided for materials used in nuclear power plants.

RBS-channeling study of radiation damage in Ar{sup +} implanted CuInSe{sub 2} crystals

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

Yakushev, Michael V., E-mail: michael.yakushev@strath.ac.uk; Ural Federal University, Ekaterinburg 620002; Institute of Solid State Chemistry of the Urals Branch of RAS, Ekaterinburg 620990

2016-09-15

Chalcopyrite solar cells are reported to have a high tolerance to irradiation by high energy electrons or ions, but the origin of this is not well understood. This work studies the evolution of damage in Ar{sup +}-bombarded CuInSe{sub 2} single crystal using Rutherford backscattering/channeling analysis. Ar{sup +} ions of 30 keV were implanted with doses in the range from 10{sup 12} to 3 × 10{sup 16} cm{sup −2} at room temperature. Implantation was found to create two layers of damage: (1) on the surface, caused by preferential sputtering of Se and Cu atoms; (2) at the layer of implanted Ar, possibly consisting of stackingmore » faults and dislocation loops. The damage in the second layer was estimated to be less than 2% of the theoretical prediction suggesting efficient healing of primary implantation defects.« less

NASALIFE - Component Fatigue and Creep Life Prediction Program

NASA Technical Reports Server (NTRS)

Gyekenyesi, John Z.; Murthy, Pappu L. N.; Mital, Subodh K.

2014-01-01

NASALIFE is a life prediction program for propulsion system components made of ceramic matrix composites (CMC) under cyclic thermo-mechanical loading and creep rupture conditions. Although the primary focus was for CMC components, the underlying methodologies are equally applicable to other material systems as well. The program references empirical data for low cycle fatigue (LCF), creep rupture, and static material properties as part of the life prediction process. Multiaxial stresses are accommodated by Von Mises based methods and a Walker model is used to address mean stress effects. Varying loads are reduced by the Rainflow counting method or a peak counting type method. Lastly, damage due to cyclic loading and creep is combined with Minor's Rule to determine damage due to cyclic loading, damage due to creep, and the total damage per mission and the number of potential missions the component can provide before failure.

The Role of Non-Targeted Effects as Mediators in the Biological Effects of Proton Irradiation

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Dicello, John F.

2006-01-01

In recent years, the hypothesis that non-DNA targets are primary initiators and mediators of the biological effects of ionizing radiation, such as proton beams and heavy ions, has gained much interest. These phenomena have been denoted as non-targeted or bystander effects to distinguish them from the more traditionally studied model that focuses on direct damage to DNA causing chromosomal rearrangements and mutations as causative of most biological endpoints such as cell killing, tissue damage, and cancer. We review cellular and extra-cellular structures and signal transduction pathways that have been implemented in these recent studies. Non-targeted effects of interest include oxidative damage to the cytoplasm and mitochondria, disruption of the extra-cellular matrix, and modification of cytokine signaling including TGF-beta, and gap junction communication. We present an introduction to these targets and pathways, and contrast there role with DNA damage pathways.

Sequential projection pursuit for optimised vibration-based damage detection in an experimental wind turbine blade

NASA Astrophysics Data System (ADS)

Hoell, Simon; Omenzetter, Piotr

2018-02-01

To advance the concept of smart structures in large systems, such as wind turbines (WTs), it is desirable to be able to detect structural damage early while using minimal instrumentation. Data-driven vibration-based damage detection methods can be competitive in that respect because global vibrational responses encompass the entire structure. Multivariate damage sensitive features (DSFs) extracted from acceleration responses enable to detect changes in a structure via statistical methods. However, even though such DSFs contain information about the structural state, they may not be optimised for the damage detection task. This paper addresses the shortcoming by exploring a DSF projection technique specialised for statistical structural damage detection. High dimensional initial DSFs are projected onto a low-dimensional space for improved damage detection performance and simultaneous computational burden reduction. The technique is based on sequential projection pursuit where the projection vectors are optimised one by one using an advanced evolutionary strategy. The approach is applied to laboratory experiments with a small-scale WT blade under wind-like excitations. Autocorrelation function coefficients calculated from acceleration signals are employed as DSFs. The optimal numbers of projection vectors are identified with the help of a fast forward selection procedure. To benchmark the proposed method, selections of original DSFs as well as principal component analysis scores from these features are additionally investigated. The optimised DSFs are tested for damage detection on previously unseen data from the healthy state and a wide range of damage scenarios. It is demonstrated that using selected subsets of the initial and transformed DSFs improves damage detectability compared to the full set of features. Furthermore, superior results can be achieved by projecting autocorrelation coefficients onto just a single optimised projection vector.

Impact damage resistance of composite fuselage structure, part 2

NASA Technical Reports Server (NTRS)

Dost, Ernest F.; Finn, Scott R.; Murphy, Daniel P.; Huisken, Amy B.

1993-01-01

The strength of laminated composite materials may be significantly reduced by foreign object impact induced damage. An understanding of the damage state is required in order to predict the behavior of structure under operational loads or to optimize the structural configuration. Types of damage typically induced in laminated materials during an impact event include transverse matrix cracking, delamination, and/or fiber breakage. The details of the damage state and its influence on structural behavior depend on the location of the impact. Damage in the skin may act as a soft inclusion or affect panel stability, while damage occurring over a stiffener may include debonding of the stiffener flange from the skin. An experiment to characterize impact damage resistance of fuselage structure as a function of structural configuration and impact threat was performed. A wide range of variables associated with aircraft fuselage structure such as material type and stiffener geometry (termed, intrinsic variables) and variables related to the operating environment such as impactor mass and diameter (termed, extrinsic variables) were studied using a statistically based design-of-experiments technique. The experimental design resulted in thirty-two different 3-stiffener panels. These configured panels were impacted in various locations with a number of impactor configurations, weights, and energies. The results obtained from an examination of impacts in the skin midbay and hail simulation impacts are documented. The current discussion is a continuation of that work with a focus on nondiscrete characterization of the midbay hail simulation impacts and discrete characterization of impact damage for impacts over the stiffener.

Minimum State Awareness for Resilient Control Systems Under Cyber-Attack

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

Kisner, Roger; Fugate, David L; McIntyre, Timothy J

2012-01-01

State awareness for a control system is the accurate knowledge of the internal states of the system realization. To maintain stable operation, a controller requires a certain degree of state awareness. By definition, a cyber-attacker decreases the state awareness by modifying or removing the information available to the operator and control system. By doing so, the attacker can directly cause damage to the physical system through the control system, or indirectly by causing the operator to react in a damaging manner to the false information. In a number of recent papers, detection and mitigation strategies have been proposed that assumemore » state awareness. The goal of the attacker to reduce or remove state awareness makes this assumption invalid for most situations. One of the central problems of resilient control is developing methods to retain sufficient state awareness to continue operation during a cyberattack. In this paper, we will define state awareness, discuss the consequences of loss of state awareness, and some potential research directions for maintaining state awareness.« less

Numerical and Experimental Validation of a New Damage Initiation Criterion

NASA Astrophysics Data System (ADS)

Sadhinoch, M.; Atzema, E. H.; Perdahcioglu, E. S.; van den Boogaard, A. H.

2017-09-01

Most commercial finite element software packages, like Abaqus, have a built-in coupled damage model where a damage evolution needs to be defined in terms of a single fracture energy value for all stress states. The Johnson-Cook criterion has been modified to be Lode parameter dependent and this Modified Johnson-Cook (MJC) criterion is used as a Damage Initiation Surface (DIS) in combination with the built-in Abaqus ductile damage model. An exponential damage evolution law has been used with a single fracture energy value. Ultimately, the simulated force-displacement curves are compared with experiments to validate the MJC criterion. 7 out of 9 fracture experiments were predicted accurately. The limitations and accuracy of the failure predictions of the newly developed damage initiation criterion will be discussed shortly.

Co-Optima Highlights Primary Causes of Misfueling and Mitigation Strategies

Science.gov Websites

% ethanol; 90% unleaded gasoline) for use in any gasoline vehicle. Many misfueling mitigation measures such lead to vehicle systems damage. Measures such as nozzle colors are not universally standardized. Fuel

Grain-damage hysteresis and plate tectonic states

NASA Astrophysics Data System (ADS)

Bercovici, David; Ricard, Yanick

2016-04-01

Shear localization in the lithosphere is an essential ingredient for understanding how and why plate tectonics is generated from mantle convection on terrestrial planets. The theoretical model for grain-damage and pinning in two-phase polycrystalline rocks provides a frame-work for understanding lithospheric shear weakening and plate-generation, and is consistent with laboratory and field observations of mylonites. Grain size evolves through the competition between coarsening, which drives grain-growth, and damage, which drives grain reduction. The interface between crystalline phases controls Zener pinning, which impedes grain growth. Damage to the interface enhances the Zener pinning effect, which then reduces grain-size, forcing the rheology into the grain-size-dependent diffusion creep regime. This process thus allows damage and rheological weakening to co-exist, providing a necessary positive self-weakening feedback. Moreover, because pinning inhibits grain-growth it promotes shear-zone longevity and plate-boundary inheritance. However, the suppression of interface damage at low interface curvature (wherein inter-grain mixing is inefficient and other energy sinks of deformational work are potentially more facile) causes a hysteresis effect, in which three possible equilibrium grain-sizes for a given stress coexist: (1) a stable, large-grain, weakly-deforming state, (2) a stable, small-grain, rapidly-deforming state analogous to ultramylonites, and (3) an unstable, intermediate grain-size state perhaps comparable to protomylonites. A comparison of the model to field data suggests that shear-localized zones of small-grain mylonites and ultra-mylonites exist at a lower stress than the co-existing large-grain porphyroclasts, rather than, as predicted by paleopiezometers or paleowattmeters, at a much higher stress; this interpretation of field data thus allows localization to relieve instead of accumulate stress. The model also predicts that a lithosphere that deforms at a given stress can acquire two stable deformation regimes indicative of plate-like flows, i.e., it permits the coexistence of both slowly deforming plate interiors, and rapidly deforming plate boundaries. Earth seems to exist squarely inside the hysteresis loop and thus can have coexisting deformation states, while Venus appears to straddle the end of the loop where only the weakly deforming branch exists.

Hematopoietic stem cell injury induced by ionizing radiation.

PubMed

Shao, Lijian; Luo, Yi; Zhou, Daohong

2014-03-20

Exposure to ionizing radiation (IR) as the result of nuclear accidents or terrorist attacks is a significant threat and a major medical concern. Hematopoietic stem cell (HSC) injury is the primary cause of death after accidental or intentional exposure to a moderate or high dose of IR. Protecting HSCs from IR should be a primary goal in the development of novel medical countermeasures against radiation. Significant progress has been made in our understanding of the mechanisms by which IR causes HSC damage. The mechanisms include (i) induction of HSC apoptosis via the p53-Puma pathway; (ii) promotion of HSC differentiation via the activation of the G-CSF/Stat3/BATF-dependent differentiation checkpoint; (iii) induction of HSC senescence via the ROS-p38 pathway; and (iv) damage to the HSC niche. Induction of apoptosis in HSCs and hematopoietic progenitor cells is primarily responsible for IR-induced acute bone marrow (BM) injury. Long-term BM suppression caused by IR is mainly attributable to the induction of HSC senescence. However, the promotion of HSC differentiation and damage to the HSC niche can contribute to both the acute and long-term effects of IR on the hematopoietic system. In this review, we have summarized a number of recent findings that provide new insights into the mechanisms whereby IR damages HSCs. These findings will provide new opportunities for developing a mechanism-based strategy to prevent and/or mitigate IR-induced BM suppression. Antioxid.

The Risk of Oxygen during Cardiac Surgery (ROCS) trial: study protocol for a randomized clinical trial.

PubMed

Lopez, Marcos G; Pretorius, Mias; Shotwell, Matthew S; Deegan, Robert; Eagle, Susan S; Bennett, Jeremy M; Sileshi, Bantayehu; Liang, Yafen; Gelfand, Brian J; Kingeter, Adam J; Siegrist, Kara K; Lombard, Frederick W; Richburg, Tiffany M; Fornero, Dane A; Shaw, Andrew D; Hernandez, Antonio; Billings, Frederic T

2017-06-26

Anesthesiologists administer excess supplemental oxygen (hyper-oxygenation) to patients during surgery to avoid hypoxia. Hyper-oxygenation, however, may increase the generation of reactive oxygen species and cause oxidative damage. In cardiac surgery, increased oxidative damage has been associated with postoperative kidney and brain injury. We hypothesize that maintenance of normoxia during cardiac surgery (physiologic oxygenation) decreases kidney injury and oxidative damage compared to hyper-oxygenation. The Risk of Oxygen during Cardiac Surgery (ROCS) trial will randomly assign 200 cardiac surgery patients to receive physiologic oxygenation, defined as the lowest fraction of inspired oxygen (FIO 2 ) necessary to maintain an arterial hemoglobin saturation of 95 to 97%, or hyper-oxygenation (FIO 2  = 1.0) during surgery. The primary clinical endpoint is serum creatinine change from baseline to postoperative day 2, and the primary mechanism endpoint is change in plasma concentrations of F 2 -isoprostanes and isofurans. Secondary endpoints include superoxide production, clinical delirium, myocardial injury, and length of stay. An endothelial function substudy will examine the effects of oxygen treatment and oxidative stress on endothelial function, measured using flow mediated dilation, peripheral arterial tonometry, and wire tension myography of epicardial fat arterioles. The ROCS trial will test the hypothesis that intraoperative physiologic oxygenation decreases oxidative damage and organ injury compared to hyper-oxygenation in patients undergoing cardiac surgery. ClinicalTrials.gov, ID: NCT02361944 . Registered on the 30th of January 2015.

Rad18 confers hematopoietic progenitor cell DNA damage tolerance independently of the Fanconi Anemia pathway in vivo

PubMed Central

Yang, Yang; Poe, Jonathan C.; Yang, Lisong; Fedoriw, Andrew; Desai, Siddhi; Magnuson, Terry; Li, Zhiguo; Fedoriw, Yuri; Araki, Kimi; Gao, Yanzhe; Tateishi, Satoshi; Sarantopoulos, Stefanie; Vaziri, Cyrus

2016-01-01

In cultured cancer cells the E3 ubiquitin ligase Rad18 activates Trans-Lesion Synthesis (TLS) and the Fanconi Anemia (FA) pathway. However, physiological roles of Rad18 in DNA damage tolerance and carcinogenesis are unknown and were investigated here. Primary hematopoietic stem and progenitor cells (HSPC) co-expressed RAD18 and FANCD2 proteins, potentially consistent with a role for Rad18 in FA pathway function during hematopoiesis. However, hematopoietic defects typically associated with fanc-deficiency (decreased HSPC numbers, reduced engraftment potential of HSPC, and Mitomycin C (MMC) -sensitive hematopoiesis), were absent in Rad18−/− mice. Moreover, primary Rad18−/− mouse embryonic fibroblasts (MEF) retained robust Fancd2 mono-ubiquitination following MMC treatment. Therefore, Rad18 is dispensable for FA pathway activation in untransformed cells and the Rad18 and FA pathways are separable in hematopoietic cells. In contrast with responses to crosslinking agents, Rad18−/− HSPC were sensitive to in vivo treatment with the myelosuppressive agent 7,12 Dimethylbenz[a]anthracene (DMBA). Rad18-deficient fibroblasts aberrantly accumulated DNA damage markers after DMBA treatment. Moreover, in vivo DMBA treatment led to increased incidence of B cell malignancy in Rad18−/− mice. These results identify novel hematopoietic functions for Rad18 and provide the first demonstration that Rad18 confers DNA damage tolerance and tumor-suppression in a physiological setting. PMID:26883629

In Vitro Neuroprotective and Anti-Inflammatory Activities of Natural and Semi-Synthetic Spirosteroid Analogues.

PubMed

García-Pupo, Laura; Zaldo-Castro, Armando; Exarchou, Vassiliki; Tacoronte-Morales, Juan Enrique; Pieters, Luc; Vanden Berghe, Wim; Nuñez-Figueredo, Yanier; Delgado-Hernández, René

2016-07-29

Two spirosteroid analogues were synthesized and evaluated for their in vitro neuroprotective activities in PC12 cells, against glutamate-induced excitotoxicity and mitochondrial damage in glucose deprivation conditions, as well as their anti-inflammatory potential in LPS/IFNγ-stimulated microglia primary cultures. We also evaluated the in vitro anti-excitotoxic and anti-inflammatory activities of natural and endogenous steroids. Our results show that the plant-derived steroid solasodine decreased PC12 glutamate-induced excitotoxicity, but not the cell death induced by mitochondrial damage and glucose deprivation. Among the two synthetic spirosteroid analogues, only the (25R)-5α-spirostan-3,6-one (S15) protected PC12 against ischemia-related in vitro models and inhibited NO production, as well as the release of IL-1β by stimulated primary microglia. These findings provide further insights into the role of specific modifications of the A and B rings of sapogenins for their neuroprotective potential.

Primary radiation damage of an FeCr alloy under pressure: Atomistic simulation

NASA Astrophysics Data System (ADS)

Tikhonchev, M. Yu.; Svetukhin, V. V.

2017-05-01

The primary radiation damage of a binary FeCr alloy deformed by applied mechanical loading is studied by an atomistic molecular dynamics simulation. Loading is simulated by specifying an applied pressure of 0.25, 1.0, and 2.5 GPa of both signs. Hydrostatic and uniaxial loading is considered along the [001], [111], [112], and [210] directions. The influence of loading on the energy of point defect formation and the threshold atomic displacement energy in single-component bcc iron is investigated. The 10-keV atomic displacement cascades in a "random" binary Fe-9 at % Cr alloy are simulated at an initial temperature of 300 K. The number of the point defects generated in a cascade is estimated, and the clustering of point defects and the spatial orientation of interstitial configurations are analyzed. Our results agree with the results of other researchers and supplement them.

The Need and Requirements for Validating Damage Detection Capability

DTIC Science & Technology

2011-09-01

Testing of Airborne Equipment [11], 2) Materials / Structure Certification, 3) NDE (POD) Validation Procedures, 4) Failure Mode Effects and Criticality...Analysis (FMECA), and 5) Cost Benefits Analysis [12]. Existing procedures for environmental testing of airborne equipment ensure flight...e.g. ultrasound or eddy current), damage type or failure conditions to detect, criticality of the damage state (e.g. safety of flight), likelihood of

Compression Strength of Composite Primary Structural Components

NASA Technical Reports Server (NTRS)

Johnson, Eric R.; Starnes, James H., Jr. (Technical Monitor)

2000-01-01

The focus of research activities under NASA Grant NAG-1-2035 was the response and failure of thin-walled structural components. The research is applicable to the primary load carrying structure of flight vehicles, with particular emphasis on fuselage and wing'structure. Analyses and tests were performed that are applicable to the following structural components an aft pressure bulkhead, or a composite pressure dome, pressure cabin damage containment, and fuselage frames subject to crash-type loads.

Perception of Primary School Teachers Regarding Impact of Child Labour on Universalization of Education at Primary Level at District Bannu

ERIC Educational Resources Information Center

Shah, Sayyed Farooq; Ghazi, S. R.; Khan, Muhammad Saqib; Irfanullah

2016-01-01

Child labour has emerged as a serious, widespread and rapid growing problem in many parts of the world. Child labour is a socio-economic issue, which not only wrecks the social growth but also damages the moral fabrics of our society. The on hand paper not only highlights this very issue but also have a close look at its major inverse affect on…

32 CFR 842.92 - Scope of this subpart.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ADMINISTRATIVE CLAIMS Property Damage Tort Claims in Favor of the United States (31 U.S.C. 3701, 3711-3719) § 842... damage to or loss or destruction of government property through negligence or wrongful act. It does not...

Modeling of two-phase porous flow with damage

NASA Astrophysics Data System (ADS)

Cai, Z.; Bercovici, D.

2009-12-01

Two-phase dynamics has been broadly studied in Earth Science in a convective system. We investigate the basic physics of compaction with damage theory and present preliminary results of both steady state and time-dependent transport when melt migrates through porous medium. In our simple 1-D model, damage would play an important role when we consider the ascent of melt-rich mixture at constant velocity. Melt segregation becomes more difficult so that porosity is larger than that in simple compaction in the steady-state compaction profile. Scaling analysis for compaction equation is performed to predict the behavior of melt segregation with damage. The time-dependent of the compacting system is investigated by looking at solitary wave solutions to the two-phase model. We assume that the additional melt is injected to the fracture material through a single pulse with determined shape and velocity. The existence of damage allows the pulse to keep moving further than that in simple compaction. Therefore more melt could be injected to the two-phase mixture and future application such as carbon dioxide injection is proposed.

Damage detection of structures identified with deterministic-stochastic models using seismic data.

PubMed

Huang, Ming-Chih; Wang, Yen-Po; Chang, Ming-Lian

2014-01-01

A deterministic-stochastic subspace identification method is adopted and experimentally verified in this study to identify the equivalent single-input-multiple-output system parameters of the discrete-time state equation. The method of damage locating vector (DLV) is then considered for damage detection. A series of shaking table tests using a five-storey steel frame has been conducted. Both single and multiple damage conditions at various locations have been considered. In the system identification analysis, either full or partial observation conditions have been taken into account. It has been shown that the damaged stories can be identified from global responses of the structure to earthquakes if sufficiently observed. In addition to detecting damage(s) with respect to the intact structure, identification of new or extended damages of the as-damaged counterpart has also been studied. This study gives further insights into the scheme in terms of effectiveness, robustness, and limitation for damage localization of frame systems.

Characteristics of shear damage for 60Sn-40Pb solder material

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

Fang, H.E.; Chow, C.L.; Wei, Y.

This paper presents an investigation of the development of a continuum damage model capable of accurately analyzing shear damage in 60Sn-40Pb solder material. Based on the theory of damage mechanics, an internal state variable known as the damage variable is introduced to characterize material degradation caused by the change of material microstructures under load. A damage surface in stress space is proposed to quantify damage initiation and its successive expanding surfaces to represent damage hardening. With the aid of irreversible thermodynamics, the damage-coupled constitutive equations and the damage evolution equations are established. A failure criterion is proposed based on themore » accumulation of overall damage in the material. The damage model is implemented in a general purpose finite element program ABAQUS through its user-defined material subroutine UMAT. The program is applied to predict shear deformation in a notched specimen. The predicted failure mode and maximum load agree well with those measured experimentally. The effect of finite element meshing on the numerical results is also examined and discussed.« less

The IPM Wheat Model--results of a three-year study in North Rhine-Westphalia, Lower Saxony and Schleswig-Holstein.

PubMed

Verreet, J A; Heger, M; Oerke, E; Dehne, H W; Finger, I; Busse, C; Klink, H

2003-01-01

Under the primary utilisation of phytosanitary production factors such as selection of variety, crop rotation and N fertilisation according to plant requirements, the IPM Wheat Model comprises the elements diagnosis (qualitative = type of pathogen, quantitative = disease severity), scientifically grounded treatment thresholds which, as critical values in pathogen development, can be applied to define the optimum time of fungicide application, and pathogen-specific effective fungicides and application amounts. This leads to the location and year-specific optimised control of the pathogen and of the associated yield performance. After several years of development in Bavaria (from 1985 on) and Schleswig-Holstein (1993-1999), the model was tested as part of a project involving the Universities of Bonn and Kiel and the plant protection services of the German states of Lower Saxony, North Rhine-Westphalia and Schleswig-Holstein in a three-year study (1999-2001) in interregional locations (usually nine per state) with the winter wheat variety Ritmo (interregional indicator variety) and a further variety of regional importance in different variations (untreated control, three to four times growth stage-oriented variants for the determination of the absolute damage potential, IPM-variant). In exact records (approx. 12 dates per vegetation period), the disease epidemics were recorded weekly. With the genetically uniform indicator variety Ritmo, the results documented substantially differing year- and location-specific disease and yield patterns. Interregionally, a broad wheat pathogen spectrum (Puccinia striiformis, P. recondita, Septoria tritici, Stagonospora (syn. Septoria) nodorum, Blumeria (syn. Erysiphe) graminis, Pseudocercosporella herpotrichoides, Drechslera tritici-repentis) in differing composition, disease severity and damage effect was demonstrated. The heterogeneity of the infection and damage patterns was increased in the case of the second variety, in association with the genetic variability. The epidemiologically-orientated indications (average two, reduced application amounts) according to the IPM Wheat Model in association with time-diverging progressions led, on an interregional basis, with minimum input and in association with the diverging dynamics, to a biologically and economically optimised fungicide application. In the context of economic and ecological performance, the comprehensive results of the project demonstrated the valuable functionality of the IPM Wheat Model.

Deletion of protein kinase C-ε attenuates mitochondrial dysfunction and ameliorates ischemic renal injury.

PubMed

Nowak, Grazyna; Takacsova-Bakajsova, Diana; Megyesi, Judit

2017-01-01

Previously, we documented that activation of protein kinase C-ε (PKC-ε) mediates mitochondrial dysfunction in cultured renal proximal tubule cells (RPTC). This study tested whether deletion of PKC-ε decreases dysfunction of renal cortical mitochondria and improves kidney function after renal ischemia. PKC-ε levels in mitochondria of ischemic kidneys increased 24 h after ischemia. Complex I- and complex II-coupled state 3 respirations were reduced 44 and 27%, respectively, in wild-type (WT) but unchanged and increased in PKC-ε-deficient (KO) mice after ischemia. Respiratory control ratio coupled to glutamate/malate oxidation decreased 50% in WT but not in KO mice. Activities of complexes I, III, and IV were decreased 59, 89, and 61%, respectively, in WT but not in KO ischemic kidneys. Proteomics revealed increases in levels of ATP synthase (α-subunit), complexes I and III, cytochrome oxidase, α-ketoglutarate dehydrogenase, and thioredoxin-dependent peroxide reductase after ischemia in KO but not in WT animals. PKC-ε deletion prevented ischemia-induced increases in oxidant production. Plasma creatinine levels increased 12-fold in WT and 3-fold in KO ischemic mice. PKC-ε deletion reduced tubular necrosis, brush border loss, and distal segment damage in ischemic kidneys. PKC-ε activation in hypoxic RPTC in primary culture exacerbated, whereas PKC-ε inhibition reduced, decreases in: 1) complex I- and complex II-coupled state 3 respirations and 2) activities of complexes I, III, and IV. We conclude that PKC-ε activation mediates 1) dysfunction of complexes I and III of the respiratory chain, 2) oxidant production, 3) morphological damage to the kidney, and 4) decreases in renal functions after ischemia. Copyright © 2017 the American Physiological Society.

Deletion of protein kinase C-ε attenuates mitochondrial dysfunction and ameliorates ischemic renal injury

PubMed Central

Takacsova-Bakajsova, Diana; Megyesi, Judit

2016-01-01

Previously, we documented that activation of protein kinase C-ε (PKC-ε) mediates mitochondrial dysfunction in cultured renal proximal tubule cells (RPTC). This study tested whether deletion of PKC-ε decreases dysfunction of renal cortical mitochondria and improves kidney function after renal ischemia. PKC-ε levels in mitochondria of ischemic kidneys increased 24 h after ischemia. Complex I- and complex II-coupled state 3 respirations were reduced 44 and 27%, respectively, in wild-type (WT) but unchanged and increased in PKC-ε-deficient (KO) mice after ischemia. Respiratory control ratio coupled to glutamate/malate oxidation decreased 50% in WT but not in KO mice. Activities of complexes I, III, and IV were decreased 59, 89, and 61%, respectively, in WT but not in KO ischemic kidneys. Proteomics revealed increases in levels of ATP synthase (α-subunit), complexes I and III, cytochrome oxidase, α-ketoglutarate dehydrogenase, and thioredoxin-dependent peroxide reductase after ischemia in KO but not in WT animals. PKC-ε deletion prevented ischemia-induced increases in oxidant production. Plasma creatinine levels increased 12-fold in WT and 3-fold in KO ischemic mice. PKC-ε deletion reduced tubular necrosis, brush border loss, and distal segment damage in ischemic kidneys. PKC-ε activation in hypoxic RPTC in primary culture exacerbated, whereas PKC-ε inhibition reduced, decreases in: 1) complex I- and complex II-coupled state 3 respirations and 2) activities of complexes I, III, and IV. We conclude that PKC-ε activation mediates 1) dysfunction of complexes I and III of the respiratory chain, 2) oxidant production, 3) morphological damage to the kidney, and 4) decreases in renal functions after ischemia. PMID:27760765

South Texas coastal classification maps - Mansfield Channel to the Rio Grande

USGS Publications Warehouse

Morton, Robert A.; Peterson, Russell L.

2006-01-01

The Nation's rapidly growing coastal population requires reliable information regarding the vulnerability of coastal regions to storm impacts. This has created a need for classifying coastal lands and evaluating storm-hazard vulnerability. Government officials and resource managers responsible for dealing with natural hazards also need accurate assessments of potential storm impacts in order to make informed decisions before, during, and after major storm events. Both economic development and coastal-damage mitigation require integrated models of storm parameters, hazard vulnerability, and expected coastal responses. Thus, storm-hazard vulnerability assessments constitute one of the fundamental components of forecasting storm impacts. Each year as many as 10 to 12 hurricanes and tropical storms will be the focus of national attention. Of particular interest are intense hurricanes (Categories 3 to 5 of the Saffir-Simpson Hurricane Scale) that have the potential to cause substantial economic and environmental damage to the Atlantic and Gulf Coasts of the United States. These coastal regions include some of the largest metropolitan areas in the country and they continue to experience rapid population growth. Based on media reports, there is a general lack of public knowledge regarding how different coastal segments will respond to the same storm or how the same coastal segment will respond differently depending on storm conditions. A primary purpose of the USGS National Assessment of Coastal Change Project is to provide accurate representations of pre-storm ground conditions for areas that are designated high priority because they have dense populations or valuable resources that are at risk. A secondary purpose is to develop a broad coastal classification that, with only minor modification, can be applied to most coastal regions in the United States.

The Actin Depolymerizing Factor (ADF)/Cofilin Signaling Pathway and DNA Damage Responses in Cancer

PubMed Central

Chang, Chun-Yuan; Leu, Jyh-Der; Lee, Yi-Jang

2015-01-01

The actin depolymerizing factor (ADF)/cofilin protein family is essential for actin dynamics, cell division, chemotaxis and tumor metastasis. Cofilin-1 (CFL-1) is a primary non-muscle isoform of the ADF/cofilin protein family accelerating the actin filamental turnover in vitro and in vivo. In response to environmental stimulation, CFL-1 enters the nucleus to regulate the actin dynamics. Although the purpose of this cytoplasm-nucleus transition remains unclear, it is speculated that the interaction between CFL-1 and DNA may influence various biological responses, including DNA damage repair. In this review, we will discuss the possible involvement of CFL-1 in DNA damage responses (DDR) induced by ionizing radiation (IR), and the implications for cancer radiotherapy. PMID:25689427

[Operative treatment strategies for multiple trauma patients : early total care versus damage control].

PubMed

Klüter, T; Lippross, S; Oestern, S; Weuster, M; Seekamp, A

2013-09-01

The treatment of multiple trauma patients is a great challenge for an interdisciplinary team. After preclinical care and subsequent treatment in the emergency room the order of the interventions is prioritized depending of the individual risk stratification. For planning the surgery management it is essential to distinguish between absolutely essential operations to prevent life-threatening situations for the patient and interventions with shiftable indications, depending on the general condition of the patient. All interventions need to be done without causing significant secondary damage to prohibit hyperinflammation and systemic inflammatory response syndrome. The challenge consists in determination of the appropriate treatment at the right point in time. In general the early primary intervention, early total care, is differentiated from the damage control concept.

Plasma induced DNA damage: Comparison with the effects of ionizing radiation

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

Lazović, S.; Maletić, D.; Puač, N.

2014-09-22

We use human primary fibroblasts for comparing plasma and gamma rays induced DNA damage. In both cases, DNA strand breaks occur, but of fundamentally different nature. Unlike gamma exposure, contact with plasma predominantly leads to single strand breaks and base-damages, while double strand breaks are mainly consequence of the cell repair mechanisms. Different cell signaling mechanisms are detected confirming this (ataxia telangiectasia mutated - ATM and ataxia telangiectasia and Rad3 related - ATR, respectively). The effective plasma doses can be tuned to match the typical therapeutic doses of 2 Gy. Tailoring the effective dose through plasma power and duration of themore » treatment enables safety precautions mainly by inducing apoptosis and consequently reduced frequency of micronuclei.« less

Acute venous sinus thrombosis after chickenpox infection.

PubMed

Sardana, Vijay; Mittal, Lal Chand; Meena, S R; Sharma, Deepti; Khandelwal, Girish

2014-08-01

Chickenpox is one of the classic childhood diseases. Recently chicken pox has been reported in adults with more severe systemic and neurological complications. Cerebral venous thrombosis (CVT) is a life threatening disorder if not treated in time. We report a patient with post varicella CVT as a rare complication of primary Varicella zoster virus. Vasculitic arterial infarction is known while venous stroke has rarely been reported with Varicella-zoster virus infection. Here, we report an immunocompetent 30 yr old male who developed chickenpox after contact with his daughter two month back. He presented with acute neurological deficit, one week after onset of skin lesion. MR venography revealed non-visualisation of left transverse sinus and left sigmoid sinus suggestive of venous sinus thrombosis. Varicella infection is rarely associated with venous sinus thrombosis. Possibly hypercoagulable state produced by the infection or direct invasion of virus in venous endothelial wall with subsequent damage to endothelium leading to thrombosis could be the cause.

Advances in MR imaging for cervical spondylotic myelopathy.

PubMed

Ellingson, Benjamin M; Salamon, Noriko; Holly, Langston T

2015-04-01

To outline the pathogenesis of cervical spondylotic myelopathy (CSM), the correlative abnormalities observed on standard magnetic resonance imaging (MRI), the biological implications and current status of diffusion tensor imaging (DTI), and MR spectroscopy (MRS) as clinical tools, and future directions of MR technology in the management of CSM patients. A systematic review of the pathogenesis and current state-of-the-art in MR imaging technology for CSM was performed. CSM is caused by progressive, degenerative, vertebral column abnormalities that result in spinal cord damage related to both primary mechanical and secondary biological injuries. The T2 signal change on conventional MRI is most commonly associated with neurological deficits, but tends not to be a sensitive predictor of recovery of function. DTI and MRS show altered microstructure and biochemistry that reflect patient-specific pathogenesis. Advanced imaging techniques, including DTI and MRS, show higher sensitivity to microstructural and biochemical changes within the cord, and may aid in management of CSM patients.

Electron beam induced damage in ITO coated Kapton. [Indium Tin Oxide

NASA Technical Reports Server (NTRS)

Krainsky, I.; Gordon, W. L.; Hoffman, R. W.

1981-01-01

Data for the stability of thin conductive indium tin oxide films on 0.003 inch thick Kapton substrates during exposure of the surface to electron beams are reported. The electron beam energy was 3 keV and the diameter was about 0.8 mm. Thermal effects and surface modifications are considered. For primary current greater than 0.6 microamperes, an obvious dark discoloration with diameter approximately that of the beam was produced. The structure of the discolored region was studied with the scanning electron microscope, and the findings are stated. Surface modifications were explored by AES, obtaining spectra and secondary emission coefficient as a function of time for different beam intensities. In all cases beam exposure results in a decrease of the secondary yield but because of thermal effects this change, as well as composition changes, cannot be directly interpreted in terms of electron beam dosage.

The role of high-fructose corn syrup in metabolic syndrome and hypertension.

PubMed

Ferder, Leon; Ferder, Marcelo Damián; Inserra, Felipe

2010-04-01

Obesity and related diseases are an important and growing health concern in the United States and around the world. Soft drinks and other sugar-sweetened beverages are now the primary sources of added sugars in Americans' diets. The metabolic syndrome is a cluster of common pathologies, including abdominal obesity linked to an excess of visceral fat, fatty liver, insulin resistance, hyperinsulinemia, dyslipidemia, and hypertension. Trends in all of these alterations are related to the consumption of dietary fructose and the introduction of high-fructose corn syrup (HFCS) as a sweetener in soft drinks and other foods. Experimental and clinical evidence suggests a progressive association between HFCS consumption, obesity, and the other injury processes. However, experimental HFCS consumption seems to produce some of the changes associated with metabolic syndrome even without increasing the body weight. Metabolic damage associated with HFCS probably is not limited to obesity-pathway mechanisms.

Thyroid hormone-induced oxidative stress.

PubMed

Venditti, P; Di Meo, S

2006-02-01

Hypermetabolic state in hyperthyroidism is associated with tissue oxidative injury. Available data indicate that hyperthyroid tissues exhibit an increased ROS and RNS production. The increased mitochondrial ROS generation is a side effect of the enhanced level of electron carriers, by which hyperthyroid tissues increase their metabolic capacity. Investigations of antioxidant defence system have returned controversial results. Moreover, other thyroid hormone-linked biochemical changes increase tissue susceptibility to oxidative challenge, which exacerbates the injury and dysfunction they suffer under stressful conditions. Mitochondria, as a primary target for oxidative stress, might account for hyperthyroidism linked tissue dysfunction. This is consistent with the inverse relationship found between functional recovery of ischemic hyperthyroid hearts and mitochondrial oxidative damage and respiration impairment. However, thyroid hormone-activated mitochondrial mechanisms provide protection against excessive tissue dysfunction, including increased expression of uncoupling proteins, proteolytic enzymes and transcriptional coactivator PGC-1, and stimulate opening of permeability transition pores.

US Air Force perspective on validated NDE - Past, present, and future

NASA Astrophysics Data System (ADS)

Lindgren, Eric A.

2016-02-01

The concept of inspection has accompanied aviation since the work of the Wright Brothers. Inspection for both initial quality/materials acceptance and readiness for flight have been coupled with US Air Force (USAF) since its inception as the US Army Signal Corps. Initial nondestructive evaluation work expanded beyond visual inspection to include radiography and magnetic particle in the 1920's and 1930's as air frames transitioned to metal and engines used higher strength steels. Within the USAF Research and Development community, a Nondestructive Test Section was stood up in 1952 and the Nondestructive Evaluation Branch (NDE) was established in 1974. In 2012 the name was changed to the Materials State Awareness Branch. This name change reflects the evolution from a primary focus on inspections for damage and defects in materials to the characterization of the underlying materials structure that governs properties of the materials of interest for Air Force applications.

Evaluation of ultrasonic cavitation of metallic and non-metallic surfaces

NASA Technical Reports Server (NTRS)

Mehta, Narinder K.

1992-01-01

1,1,2 trichloro-1,2,2 trifluoro ethane (CFC-113) commercially known as Freon-113 is the primary test solvent used for validating the cleaned hardware at the Kennedy Space Center (KSC). Due to the ozone depletion problem, the current United States policy calls for the phase out of Freons by 1995. NASAs chlorofluorocarbon (CFC) replacement group at KSC has opted to use water as a replacement fluid for the validation process since water is non-toxic, inexpensive, and is environmentally friendly. The replacement validation method calls for the ultrasonification of the small parts with water at 52 C for a cycle or two of 10 min duration wash using commercial ultrasonic baths. In this project, experimental data was obtained to assess the applicability of the proposed validation method for any damage of the metallic and non-metallic surfaces resulting from ultrasonic cavitation.

Identification of characteristic frequencies of damaged railway tracks using field hammer test measurements

NASA Astrophysics Data System (ADS)

Oregui, M.; Li, Z.; Dollevoet, R.

2015-03-01

In this paper, the feasibility of the Frequency Response Function (FRF)-based statistical method to identify the characteristic frequencies of railway track defects is studied. The method compares a damaged track state to a healthy state based on non-destructive field hammer test measurements. First, a study is carried out to investigate the repeatability of hammer tests in railway tracks. By changing the excitation and measurement locations it is shown that the variability introduced by the test process is negligible. Second, following the concepts of control charts employed in process monitoring, a method to define an approximate healthy state is introduced by using hammer test measurements at locations without visual damage. Then, the feasibility study includes an investigation into squats (i.e. a major type of rail surface defect) of varying severity. The identified frequency ranges related to squats agree with those found in an extensively validated vehicle-borne detection system. Therefore, the FRF-based statistical method in combination with the non-destructive hammer test measurements has the potential to be employed to identify the characteristic frequencies of damaged conditions in railway tracks in the frequency range of 300-3000 Hz.

Medical Malpractice Reform and Employer-Sponsored Health Insurance Premiums

PubMed Central

Morrisey, Michael A; Kilgore, Meredith L; Nelson, Leonard (Jack)

2008-01-01

Objective Tort reform may affect health insurance premiums both by reducing medical malpractice premiums and by reducing the extent of defensive medicine. The objective of this study is to estimate the effects of noneconomic damage caps on the premiums for employer-sponsored health insurance. Data Sources/Study Setting Employer premium data and plan/establishment characteristics were obtained from the 1999 through 2004 Kaiser/HRET Employer Health Insurance Surveys. Damage caps were obtained and dated based on state annotated codes, statutes, and judicial decisions. Study Design Fixed effects regression models were run to estimate the effects of the size of inflation-adjusted damage caps on the weighted average single premiums. Data Collection/Extraction Methods State tort reform laws were identified using Westlaw, LEXIS, and statutory compilations. Legislative repeal and amendment of statutes and court decisions resulting in the overturning or repealing state statutes were also identified using LEXIS. Principal Findings Using a variety of empirical specifications, there was no statistically significant evidence that noneconomic damage caps exerted any meaningful influence on the cost of employer-sponsored health insurance. Conclusions The findings suggest that tort reforms have not translated into insurance savings. PMID:18522666

In-Situ Spectrometry of Neutrons

NASA Technical Reports Server (NTRS)

Maurer, Richard H.

1999-01-01

High energy charged particles of extra-galactic, galactic and solar origin collide with spacecraft structures in Earth orbit outside the atmosphere and in interplanetary travel beyond the Earth's magnetosphere. These primaries create a number of secondary particles inside the structures that can produce a significant ionizing radiation environment. This radiation is a threat to long term inhabitants or travelers for space missions and produces an increased risk of cancer and DNA damage. The primary high energy cosmic rays and trapped protons collide with common spacecraft materials such as aluminum and silicon and create secondary particles inside structures that are mostly protons and neutrons. Charged protons are readily detected and instruments are already in existence for this task. Neutrons are electrically neutral and therefore much more difficult to measure and detect. These neutrons are reported to contribute 30-60% of the dose inside space structures and cannot be ignored. Currently there is no compact, portable and real time neutron detector instrumentation available for use inside spacecraft or on planetary surfaces where astronauts will live and work. We propose to design and build a portable, low power and robust neutron spectrometer that will measure the neutron spectrum from 10 KeV to 500 MeV with at least 10% energy resolution in the various energy intervals. This instrument will monitor the existing neutron environment both inside spacecraft structures and on planetary surfaces to determine the safest living areas, warn of high fluxes associated with solar storms and assist the NSBRI Radiation Effects Team in making an accurate assessment of increased cancer risk and DNA damage to astronauts. The instrument uses a highly efficient proportional counter Helium 3 tube at the lowest energy intervals where .equivalent damage factors for tissue are the highest (10 KeV-2 MeV). The Helium 3 tube may be shielded with a cadmium absorber to eliminate the much less damaging, but more prevalent, thermal and epithermal neutrons and to make the structure of the spectrum more accurate in the 20 KeV-2 MeV range; or a pair of tubes, one shielded and one unshielded, can be combined so that the difference in their counts yields the thermal neutron contribution. The spectrometer also uses a 5mm lithium drifted bulk silicon solid state detector in the medium energy range of 2-20 Mev and two standard silicon surface barrier detectors separated by tens of millimeters behind a I cm thick polyethylene moderator in a stack or telescope arrangement for the high energy neutrons (>20 MeV). In the medium and high energy regions equivalent damage factors are lower but hits from one or a small number of neutrons may prove to be important. The silicon detector systems for medium and high energy neutrons will discriminate against charged particles by using a plastic cesium iodide scintillator of an appropriate geometry monitored by a silicon PIN photodiode.

Efficacy and safety of damage control in experimental animal models of injury: protocol for a systematic review and meta-analysis

PubMed Central

2014-01-01

Background Although abbreviated surgery with planned reoperation (damage control surgery) is now widely used to manage major trauma patients, the procedure and its component interventions have not been evaluated in randomized controlled trials (RCTs). While some have suggested the need for such trials, they are unlikely to be conducted because of patient safety concerns. As animal studies may overcome several of the limitations of existing observational damage control studies, the primary objective of this study is to evaluate the efficacy and safety of damage control versus definitive surgery in experimental animal models of injury. Methods/design We will search electronic databases (Medline, Embase, PubMed, Web of Science, Scopus, and the Cochrane Library), conference abstracts, personal files, and bibliographies of included articles. We will include RCTs and prospective cohort studies that utilized an animal model of injury and compared damage control surgery (or specific damage control interventions or adjuncts) to definitive surgery (or specific definitive surgical interventions). Two investigators will independently evaluate the internal and external/construct validity of individual studies. The primary outcome will be all-cause mortality. Secondary outcomes will include blood loss amounts; blood pressures and heart rates; urinary outputs; core body temperatures; arterial lactate, pH, and base deficit/excess values; prothrombin and partial thromboplastin times; international normalized ratios; and thromboelastography (TEG) results/activated clotting times. We will calculate summary relative risks (RRs) of mortality and mean differences (for continuous outcomes) using DerSimonian and Laird random effects models. Heterogeneity will be explored using subgroup meta-analysis and meta-regression. We will assess for publication bias using funnel plots and Begg’s and Egger’s tests. When evidence of publication bias exists, we will use the Duval and Tweedie trim and fill method to estimate the potential influence of this bias on pooled summary estimates. Discussion This study will evaluate the efficacy and safety of damage control in experimental animal models of injury. Study results will be used to guide future clinical evaluations of damage control surgery, determine which animal study outcomes may potentially be generalizable to the clinical setting, and to provide guidelines to strengthen the conduct and relevance of future pre-clinical studies. PMID:25416175

Assessment of ecosystem productivity damage due to land use.

PubMed

Kaenchan, Piyanon; Guinée, Jeroen; Gheewala, Shabbir H

2018-04-15

Land use can affect ecosystems on land and their services. Because land use has mainly local effects, damage to ecosystem productivity due to land use should be modelled spatially dependent. Unfortunately, even though land use of impacts are particular importance for countries whose economies are highly agriculture-based, ecosystem productivity damage due to land use has not yet been assessed in Thailand so far. This study presents the method for assessing the damage to ecosystem productivity due to land use (land occupation and land transformation) in Thailand. Ecosystem productivity damage is expressed through net primary production (NPP). To convert the damage into monetary units, this study performs an economic valuation of NPP using the production function approach. The results show that the value of marginal product of NPP is around 10-15 Thai baht (THB) (1 USD≈36 THB), per tonne dry weight biomass. The results are applied to the case of biodiesel production. The method presented in this paper could be a guideline for future land use impact assessment research. In addition, converting the NPP damage results into monetary units facilitates integration of impact assessment and economic analysis results for supporting decision support tools such as cost benefit analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

Genotoxicity analysis of two halonitromethanes, a novel group of disinfection by-products (DBPs), in human cells treated in vitro

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

Liviac, Danae; Creus, Amadeu; Marcos, Ricard

Halonitromethanes (HNMs) constitute an emerging class of disinfection by-products (DBPs) produced when chlorine and/or ozone are used for water treatment. The HNMs are structurally similar to halomethanes, but have a nitro-group in place of hydrogen bonded to the central carbon atom. Since little information exists on the genotoxic potential of HNMs, a study has been carried out with two HNM compounds, namely trichloronitromethane (TCNM) and bromonitromethane (BNM) by using human cells. Primary damage induction has been measured with the Comet assay, which is used to determine both the repair kinetics of the induced damage and the proportion of induced oxidativemore » damage. In addition, the fixed DNA damage has been evaluated by using the micronucleus (MN) assay. The results obtained indicate that both compounds are genotoxic, inducing high levels of DNA breaks in the Comet assay, and that this DNA damage repairs well over time. In addition, oxidized bases constitute a high proportion of DNA-induced damage (50-75%). Contrarily, no positive effects were observed in the frequency of micronucleus, which measures both clastogenic and aneugenic effects, neither using TK6 cells nor peripheral blood lymphocytes. This lack of fixed genetic damage would minimize the potential mutagenic risk associated with HNMs exposure.« less

Evaluation of primary DNA damage, cytogenetic biomarkers and genetic polymorphisms for CYP1A1 and GSTM1 in road tunnel construction workers.

PubMed

Villarini, M; Moretti, M; Fatigoni, C; Agea, E; Dominici, L; Mattioli, A; Volpi, R; Pasquini, R

2008-01-01

In tunnel construction workers, occupational exposure to dust (alpha-quartz and other particles from blasting), gases (nitrogen dioxide, NO(2)), diesel exhausts, and oil mist has been associated with lung function decline, induction of inflammatory reactions in the lungs with release of mediators that may influence blood coagulation, and increased risk of chronic obstructive pulmonary disease. The present molecular epidemiology study was designed to evaluate whether occupational exposure to indoor pollutants during road tunnel construction might result in genotoxic effects. A study group of 39 underground workers and a reference group of 34 unexposed subjects were examined. Primary and oxidative DNA damage, sister-chromatid exchanges (SCE), and micronuclei (MN) were measured in peripheral blood cells. The possible influences of polymorphisms in gene encoding for CYP1A1 and GSTM1 xenobiotic-metabolizing enzymes were also investigated. Exposure assessment was performed with detailed interviews and questionnaires. There were no significant differences in the level of primary and oxidative DNA damage and frequency of SCE between the tunnel workers and controls, whereas the frequency of MN showed a significant increase in exposed subjects compared to controls. No effects of CYP1A1 or GSTM1 variants were observed for the analyzed biomarkers. Since MN in peripheral blood lymphocytes are recognized as a predictive biomarker of cancer risk within a population of healthy subjects, the genotoxic risk of occupational exposure to various indoor environmental pollutants during road tunnel construction cannot be excluded by this biomonitoring study.

Investigation of antioxidant systems in human meibomian gland and conjunctival tissues.

PubMed

Nezzar, Hachemi; Mbekeani, Joyce N; Noblanc, Anais; Chiambaretta, Frédéric; Drevet, Joël R; Kocer, Ayhan

2017-12-01

Oxidative stress (OS) associated with direct contact with the environment and light exposure is a very potent and continuous stressor of the ocular surface and internal structures of the eye that are required to manage its effects. Constant replenishment of tears together with the superficial lipid layer produced by the meibomian glands (MG) is one protective mechanism. The lipid-rich fraction of the tears coats the deeper aqueous fraction, preventing its evaporation. However, lipids are particularly sensitive to oxidative damage that could alter tear film quality. To counteract oxidative damage, MG along with other structures of the ocular surface use primary antioxidant (AO) systems to limit OS damage such as lipid peroxidation. Limited information concerning the primary enzymatic AO system of the human MG prompted this investigation. Using different approaches (RT-PCR, enzymatic activity assays and immuno-fluorescent microscopy), we determined the presence, distribution and subcellular locations of the major AO enzymes belonging to the classical catalytic triad (superoxide dismutase, catalase and glutathione peroxidases) in adult human MG and conjunctiva (Conj). We showed that both tissues exhibit glutathione peroxidase expression. In addition to the ubiquitous cytosolic GPx1 protein, there was significant expression of GPx2, GPx4 and GPx7. These isoforms are known to preferentially scavenge phospholipid-hydroperoxide compounds. This characterization of the primary AO system of human MG and Conj may help pave the way for the development of diagnostic procedures and have implications for treatment of common MG dysfunction (MGD) and dry eye syndrome (DES). Copyright © 2017 Elsevier Ltd. All rights reserved.

Statistical study of single and multiple pulse laser-induced damage in glasses.

PubMed

Gallais, L; Natoli, J; Amra, C

2002-12-16

Single and multiple pulse laser damage studies are performed in Suprasil silica and BK-7 borosilicate glasses. Experiments are made in the bulk of materials at 1.064microm with nanosecond pulses, using an accurate and reliable measurement system. By means of a statistical study on laser damage probabilities, we demonstrate that the same nano-precursors could be involved in the multiple shot and single shot damage process. A damage mechanism with two stages is then proposed to explain the results. Firstly, a pre-damage process, corresponding to material changes at a microscopic level, leads the precursor to a state that can induce a one-pulse damage. And secondly a final damage occurs, with a mechanism identical to the single shot case. For each material, a law is found to predict the precursor life-time. We can then deduce the long term life of optical elements in high-power laser systems submitted to multipulse irradiation.

A study of material damping in large space structures

NASA Technical Reports Server (NTRS)

Highsmith, A. L.; Allen, D. H.

1989-01-01

A constitutive model was developed for predicting damping as a function of damage in continuous fiber reinforced laminated composites. The damage model is a continuum formulation, and uses internal state variables to quantify damage and its subsequent effect on material response. The model is sensitive to the stacking sequence of the laminate. Given appropriate baseline data from unidirectional material, and damping as a function of damage in one crossply laminate, damage can be predicted as a function of damage in other crossply laminates. Agreement between theory and experiment was quite good. A micromechanics model was also developed for examining the influence of damage on damping. This model explicitly includes crack surfaces. The model provides reasonable predictions of bending stiffness as a function of damage. Damping predictions are not in agreement with the experiment. This is thought to be a result of dissipation mechanisms such as friction, which are not presently included in the analysis.

Fatigue damage mechanics of notched graphite-epoxy laminates

NASA Astrophysics Data System (ADS)

Spearing, Mark; Beaumont, Peter W. R.; Ashby, Michael F.

A modeling approach is presented that recognizes that the residual properties of composite laminates after any form of loading depend on the damage state. Therefore, in the case of cyclic loading, it is necessary to first derive a damage growth law and then relate the residual properties to the accumulated damage. The propagation of fatigue damage in notched laminates is investigated. A power law relationship between damage growth and the strain energy release rate is developed. The material constants used in the model have been determined in independent experiments and are invariant for all the layups investigated. The strain energy release rates are calculated using a simple finite element representation of the damaged specimen. The model is used to predict the effect of tension-tension cyclic loading on laminates of the T300/914C carbon-fiber epoxy system. The extent of damage propagation is successfully predicted in a number of cross-ply laminates.

Cigarette smoking and cutaneous damage in systemic lupus erythematosus.

PubMed

Turchin, Irina; Bernatsky, Sasha; Clarke, Ann E; St-Pierre, Yvan; Pineau, Christian A

2009-12-01

To evaluate the association between cigarette smoking and cutaneous damage in systemic lupus erythematosus (SLE). Our study was performed in SLE clinic registry cohort patients, all of whom fulfilled revised American College of Rheumatology criteria for SLE; patients are followed prospectively with annual assessments that include collection of demographic variables, smoking history, disease activity (SLE Disease Activity Index version 2000, SLEDAI-2K), medications, and damage scores (Systemic Lupus International Collaborating Clinics/ACR Damage Index). Cumulative cutaneous damage scores were used for the primary analyses. Logistic and logit regression models were performed to examine potential associations between current smoking and cutaneous damage, controlling for age, sex, race, lupus disease duration, antimalarial or immunosuppressant use, and anti-DNA and anti-SSA antibody status. Of our sample (N = 276), 92% were women and 73.7% were Caucasian; the mean age was 45.1 years, mean disease duration 13.5 years, and 17.5% were current smokers. In the regression analyses, current cigarette smoking was associated with total cutaneous damage (OR 2.73, 95% CI 1.10, 6.81) and with scarring (OR 4.70, 95 CI 1.04, 21.2). In additional analyses, current smoking was also associated with active lupus rash (OR 6.18, 95% CI 1.63, 23.3). Current cigarette smoking may be associated with cutaneous damage and active lupus rash in SLE, suggesting another reason to emphasize smoking cessation in patients with SLE.

Applying robust variant of Principal Component Analysis as a damage detector in the presence of outliers

NASA Astrophysics Data System (ADS)

Gharibnezhad, Fahit; Mujica, Luis E.; Rodellar, José

2015-01-01

Using Principal Component Analysis (PCA) for Structural Health Monitoring (SHM) has received considerable attention over the past few years. PCA has been used not only as a direct method to identify, classify and localize damages but also as a significant primary step for other methods. Despite several positive specifications that PCA conveys, it is very sensitive to outliers. Outliers are anomalous observations that can affect the variance and the covariance as vital parts of PCA method. Therefore, the results based on PCA in the presence of outliers are not fully satisfactory. As a main contribution, this work suggests the use of robust variant of PCA not sensitive to outliers, as an effective way to deal with this problem in SHM field. In addition, the robust PCA is compared with the classical PCA in the sense of detecting probable damages. The comparison between the results shows that robust PCA can distinguish the damages much better than using classical one, and even in many cases allows the detection where classic PCA is not able to discern between damaged and non-damaged structures. Moreover, different types of robust PCA are compared with each other as well as with classical counterpart in the term of damage detection. All the results are obtained through experiments with an aircraft turbine blade using piezoelectric transducers as sensors and actuators and adding simulated damages.

Evaluation of Repair Techniques for Impact-Damaged Prestressed Beams

DOT National Transportation Integrated Search

2018-05-01

Collisions between over-height vehicles and bridges occur about 1,000 times per year in the United States. Collision damage to bridges can range from minor to catastrophic, potentially requiring repair or replacement of a bridge beam. For prestressed...

43 CFR 11.20 - Notification and detection.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 11.20 Public Lands: Interior Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE... CERCLA requires prompt notification of Federal and State natural resource trustees of potential damages to natural resources under investigation and requires coordination of the assessments, investigations...

43 CFR 11.20 - Notification and detection.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 11.20 Public Lands: Interior Office of the Secretary of the Interior NATURAL RESOURCE DAMAGE... CERCLA requires prompt notification of Federal and State natural resource trustees of potential damages to natural resources under investigation and requires coordination of the assessments, investigations...

Macrodamage Accumulation Model for a Human Femur

PubMed Central

2017-01-01

The objective of this study was to more fully understand the mechanical behavior of bone tissue that is important to find an alternative material to be used as an implant and to develop an accurate model to predict the fracture of the bone. Predicting and preventing bone failure is an important area in orthopaedics. In this paper, the macrodamage accumulation models in the bone tissue have been investigated. Phenomenological models for bone damage have been discussed in detail. In addition, 3D finite element model of the femur prepared from imaging data with both cortical and trabecular structures is delineated using MIMICS and ANSYS® and simulated as a composite structure. The damage accumulation occurring during cyclic loading was analyzed for fatigue scenario. We found that the damage accumulates sooner in the multiaxial than in the uniaxial loading condition for the same number of cycles, and the failure starts in the cortical bone. The damage accumulation behavior seems to follow a three-stage growth: a primary phase, a secondary phase of damage growth marked by linear damage growth, and a tertiary phase that leads to failure. Finally, the stiffness of the composite bone comprising the cortical and trabecular bone was significantly different as expected. PMID:28951659

Walnut polyphenols prevent liver damage induced by carbon tetrachloride and d-galactosamine: hepatoprotective hydrolyzable tannins in the kernel pellicles of walnut.

PubMed

Shimoda, Hiroshi; Tanaka, Junji; Kikuchi, Mitsunori; Fukuda, Toshiyuji; Ito, Hideyuki; Hatano, Tsutomu; Yoshida, Takashi

2008-06-25

The polyphenol-rich fraction (WP, 45% polyphenol) prepared from the kernel pellicles of walnuts was assessed for its hepatoprotective effect in mice. A single oral administration of WP (200 mg/kg) significantly suppressed serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) elevation in liver injury induced by carbon tetrachloride (CCl 4), while it did not suppress d-galactosamine (GalN)-induced liver injury. In order to identify the active principles in WP, we examined individual constituents for the protective effect on cell damage induced by CCl 4 and d-GalN in primary cultured rat hepatocytes. WP was effective against both CCl 4- and d-GalN-induced hepatocyte damages. Among the constituents, only ellagitannins with a galloylated glucopyranose core, such as tellimagrandins I, II, and rugosin C, suppressed CCl 4-induced hepatocyte damage significantly. Most of the ellagitannins including tellimagrandin I and 2,3- O-hexahydroxydiphenoylglucose exhibited remarkable inhibitory effect against d-GalN-induced damage. Telliamgrandin I especially completely suppressed both CCl 4- and d-GalN-induced cell damage, and thus is likely the principal constituent for the hepatoprotective effect of WP.

A damage mechanics based general purpose interface/contact element

NASA Astrophysics Data System (ADS)

Yan, Chengyong

Most of the microelectronics packaging structures consist of layered substrates connected with bonding materials, such as solder or epoxy. Predicting the thermomechanical behavior of these multilayered structures is a challenging task in electronic packaging engineering. In a layered structure the most complex part is always the interfaces between the strates. Simulating the thermo-mechanical behavior of such interfaces, is the main theme of this dissertation. The most commonly used solder material, Pb-Sn alloy, has a very low melting temperature 180sp°C, so that the material demonstrates a highly viscous behavior. And, creep usually dominates the failure mechanism. Hence, the theory of viscoplasticity is adapted to describe the constitutive behavior. In a multilayered assembly each layer has a different coefficient of thermal expansion. Under thermal cycling, due to heat dissipated from circuits, interfaces and interconnects experience low cycle fatigue. Presently, the state-of-the art damage mechanics model used for fatigue life predictions is based on Kachanov (1986) continuum damage model. This model uses plastic strain as a damage criterion. Since plastic strain is a stress path dependent value, the criterion does not yield unique damage values for the same state of stress. In this dissertation a new damage evolution equation based on the second law of thermodynamic is proposed. The new criterion is based on the entropy of the system and it yields unique damage values for all stress paths to the final state of stress. In the electronics industry, there is a strong desire to develop fatigue free interconnections. The proposed interface/contact element can also simulate the behavior of the fatigue free Z-direction thin film interconnections as well as traditional layered interconnects. The proposed interface element can simulate behavior of a bonded interface or unbonded sliding interface, also called contact element. The proposed element was verified against laboratory test data presented in the literature. The results demonstrate that the proposed element and the damage law perform very well. The most important scientific contribution of this dissertation is the proposed damage criterion based on second law of thermodynamic and entropy of the system. The proposed general purpose interface/contact element is another contribution of this research. Compared to the previous adhoc interface elements proposed in the literature, the new one is, much more powerful and includes creep, plastic deformations, sliding, temperature, damage, cyclic behavior and fatigue life in a unified formulation.

Damage Evolution in Complex-Phase and Dual-Phase Steels during Edge Stretching.

PubMed

Pathak, Nikky; Butcher, Cliff; Worswick, Michael James; Bellhouse, Erika; Gao, Jeff

2017-03-27

The role of microstructural damage in controlling the edge stretchability of Complex-Phase (CP) and Dual-Phase (DP) steels was evaluated using hole tension experiments. The experiments considered a tensile specimen with a hole at the center of specimen that is either sheared (sheared edge condition) or drilled and then reamed (reamed edge condition). The damage mechanism and accumulation in the CP and DP steels were systematically characterized by interrupting the hole tension tests at different strain levels using scanning electron microscope (SEM) analysis and optical microscopy. Martensite cracking and decohesion of ferrite-martensite interfaces are the dominant nucleation mechanisms in the DP780. The primary source of void nucleation in the CP800 is nucleation at TiN particles, with secondary void formation at martensite/bainite interfaces near the failure strain. The rate of damage evolution is considerably higher for the sheared edge in contrast with the reamed edge since the shearing process alters the microstructure in the shear affected zone (SAZ) by introducing work-hardening and initial damage behind the sheared edge. The CP microstructures were shown to be less prone to shear-induced damage than the DP materials resulting in much higher sheared edge formability. Microstructural damage in the CP and DP steels was characterized to understand the interaction between microstructure, damage evolution and edge formability during edge stretching. An analytical model for void evolution and coalescence was developed and applied to predict the damage rate in these rather diverse microstructures.

Damage Evolution in Complex-Phase and Dual-Phase Steels during Edge Stretching

PubMed Central

Pathak, Nikky; Butcher, Cliff; Worswick, Michael James; Bellhouse, Erika; Gao, Jeff

2017-01-01

The role of microstructural damage in controlling the edge stretchability of Complex-Phase (CP) and Dual-Phase (DP) steels was evaluated using hole tension experiments. The experiments considered a tensile specimen with a hole at the center of specimen that is either sheared (sheared edge condition) or drilled and then reamed (reamed edge condition). The damage mechanism and accumulation in the CP and DP steels were systematically characterized by interrupting the hole tension tests at different strain levels using scanning electron microscope (SEM) analysis and optical microscopy. Martensite cracking and decohesion of ferrite-martensite interfaces are the dominant nucleation mechanisms in the DP780. The primary source of void nucleation in the CP800 is nucleation at TiN particles, with secondary void formation at martensite/bainite interfaces near the failure strain. The rate of damage evolution is considerably higher for the sheared edge in contrast with the reamed edge since the shearing process alters the microstructure in the shear affected zone (SAZ) by introducing work-hardening and initial damage behind the sheared edge. The CP microstructures were shown to be less prone to shear-induced damage than the DP materials resulting in much higher sheared edge formability. Microstructural damage in the CP and DP steels was characterized to understand the interaction between microstructure, damage evolution and edge formability during edge stretching. An analytical model for void evolution and coalescence was developed and applied to predict the damage rate in these rather diverse microstructures. PMID:28772707

Fatigue behavior of thermal sprayed WC-CoCr- steel systems: Role of process and deposition parameters

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

Vackel, Andrew; Sampath, Sanjay

Thermal spray deposited WC-CoCr coatings are extensively used for surface protection of wear prone components in a variety of applications. Although the primary purpose of the coating is wear and corrosion protection, many of the coated components are structural systems (aero landing gear, hydraulic cylinders, drive shafts etc.) and as such experience cyclic loading during service and are potentially prone to fatigue failure. It is of interest to ensure that the coating and the application process does not deleteriously affect the fatigue strength of the parent structural metal. It has long been appreciated that the relative fatigue life of amore » thermal sprayed component can be affected by the residual stresses arising from coating deposition. The magnitude of these stresses can be managed by torch processing parameters and can also be influenced by deposition effects, particularly the deposition temperature. In this study, the effect of both torch operating parameters (particle states) and deposition conditions (notably substrate temperature) were investigated through rotating bending fatigue studies. The results indicate a strong influence of process parameters on relative fatigue life, including credit or debit to the substrate's fatigue life measured via rotating bend beam studies. Damage progression within the substrate was further explored by stripping the coating off part way through fatigue testing, revealing a delay in the onset of substrate damage with more fatigue resistant coatings but no benefit with coatings with inadequate properties. Finally, the results indicate that compressive residual stress and adequate load bearing capability of the coating (both controlled by torch and deposition parameters) delay onset of substrate damage, enabling fatigue credit of the coated component.« less

Fatigue behavior of thermal sprayed WC-CoCr- steel systems: Role of process and deposition parameters

DOE PAGES

Vackel, Andrew; Sampath, Sanjay

2017-02-27

Thermal spray deposited WC-CoCr coatings are extensively used for surface protection of wear prone components in a variety of applications. Although the primary purpose of the coating is wear and corrosion protection, many of the coated components are structural systems (aero landing gear, hydraulic cylinders, drive shafts etc.) and as such experience cyclic loading during service and are potentially prone to fatigue failure. It is of interest to ensure that the coating and the application process does not deleteriously affect the fatigue strength of the parent structural metal. It has long been appreciated that the relative fatigue life of amore » thermal sprayed component can be affected by the residual stresses arising from coating deposition. The magnitude of these stresses can be managed by torch processing parameters and can also be influenced by deposition effects, particularly the deposition temperature. In this study, the effect of both torch operating parameters (particle states) and deposition conditions (notably substrate temperature) were investigated through rotating bending fatigue studies. The results indicate a strong influence of process parameters on relative fatigue life, including credit or debit to the substrate's fatigue life measured via rotating bend beam studies. Damage progression within the substrate was further explored by stripping the coating off part way through fatigue testing, revealing a delay in the onset of substrate damage with more fatigue resistant coatings but no benefit with coatings with inadequate properties. Finally, the results indicate that compressive residual stress and adequate load bearing capability of the coating (both controlled by torch and deposition parameters) delay onset of substrate damage, enabling fatigue credit of the coated component.« less

Prolonged lifespan with enhanced exploratory behavior in mice overexpressing the oxidized nucleoside triphosphatase hMTH1.

PubMed

De Luca, Gabriele; Ventura, Ilenia; Sanghez, Valentina; Russo, Maria Teresa; Ajmone-Cat, Maria Antonietta; Cacci, Emanuele; Martire, Alberto; Popoli, Patrizia; Falcone, Germana; Michelini, Flavia; Crescenzi, Marco; Degan, Paolo; Minghetti, Luisa; Bignami, Margherita; Calamandrei, Gemma

2013-08-01

The contribution that oxidative damage to DNA and/or RNA makes to the aging process remains undefined. In this study, we used the hMTH1-Tg mouse model to investigate how oxidative damage to nucleic acids affects aging. hMTH1-Tg mice express high levels of the hMTH1 hydrolase that degrades 8-oxodGTP and 8-oxoGTP and excludes 8-oxoguanine from both DNA and RNA. Compared to wild-type animals, hMTH1-overexpressing mice have significantly lower steady-state levels of 8-oxoguanine in both nuclear and mitochondrial DNA of several organs, including the brain. hMTH1 overexpression prevents the age-dependent accumulation of DNA 8-oxoguanine that occurs in wild-type mice. These lower levels of oxidized guanines are associated with increased longevity and hMTH1-Tg animals live significantly longer than their wild-type littermates. Neither lipid oxidation nor overall antioxidant status is significantly affected by hMTH1 overexpression. At the cellular level, neurospheres derived from adult hMTH1-Tg neural progenitor cells display increased proliferative capacity and primary fibroblasts from hMTH1-Tg embryos do not undergo overt senescence in vitro. The significantly lower levels of oxidized DNA/RNA in transgenic animals are associated with behavioral changes. These mice show reduced anxiety and enhanced investigation of environmental and social cues. Longevity conferred by overexpression of a single nucleotide hydrolase in hMTH1-Tg animals is an example of lifespan extension associated with healthy aging. It provides a link between aging and oxidative damage to nucleic acids. © 2013 John Wiley & Sons Ltd and the Anatomical Society.

Human Papillomavirus Types 16 and 18 Early-expressed Proteins Differentially Modulate the Cellular Redox State and DNA Damage

PubMed Central

Cruz-Gregorio, Alfredo; Manzo-Merino, Joaquín; Gonzaléz-García, María Cecilia; Pedraza-Chaverri, José; Medina-Campos, Omar Noel; Valverde, Mahara; Rojas, Emilio; Rodríguez-Sastre, María Alexandra; García-Cuellar, Claudia María; Lizano, Marcela

2018-01-01

Oxidative stress has been proposed as a risk factor for cervical cancer development. However, few studies have evaluated the redox state associated with human papillomavirus (HPV) infection. The aim of this work was to determine the role of the early expressed viral proteins E1, E2, E6 and E7 from HPV types 16 and 18 in the modulation of the redox state in an integral form. Therefore, generation of reactive oxygen species (ROS), concentration of reduced glutathione (GSH), levels and activity of the antioxidant enzymes catalase and superoxide dismutase (SOD) and deoxyribonucleic acid (DNA) damage, were analysed in epithelial cells ectopically expressing the viral proteins. Our research shows that E6 oncoproteins decreased GSH and catalase protein levels, as well as its enzymatic activity, which was associated with an increase in ROS production and DNA damage. In contrast, E7 oncoproteins increased GSH, as well as catalase protein levels and its activity, which correlated with a decrease in ROS without affecting DNA integrity. The co-expression of both E6 and E7 oncoproteins neutralized the effects that were independently observed for each of the viral proteins. Additionally, the combined expression of E1 and E2 proteins increased ROS levels with the subsequent increase in the marker for DNA damage phospho-histone 2AX (γH2AX). A decrease in GSH, as well as SOD2 levels and activity were also detected in the presence of E1 and E2, even though catalase activity increased. This study demonstrates that HPV early expressed proteins differentially modulate cellular redox state and DNA damage. PMID:29483822