Science.gov

Sample records for acad bras cienc

  1. Selected Sports Bras: Overall Comfort and Support.

    ERIC Educational Resources Information Center

    Lawson, LaJean; Lorentzen, Deana

    This study evaluated currently marketed sports bras on subjective measures of comfort and support both within an entire group of women and within cup sizes, correlated the subjective measures of comfort and support with previously reported biomechanical findings of support on the same bras, and further developed empirically based guidelines for…

  2. Genetics Home Reference: Knobloch syndrome

    MedlinePlus

    ... the human phenotype. An Acad Bras Cienc. 2006 Mar;78(1):123-31. Epub 2006 Mar 8. Review. Citation on PubMed Seaver LH, Joffe ... XVIII in development and disease. Matrix Biol. 2011 Mar;30(2):83-92. doi: 10.1016/j. ...

  3. Selected Sports Bras: A Biomechanical Analysis of Breast Motion While Jogging.

    ERIC Educational Resources Information Center

    Lorentzen, Deana; Lawson, LaJean

    1987-01-01

    Eight sports bras were compared and evaluated to determine the amount of biomechanical support they provide for small-, medium-, and large-breasted women (N=59) while jogging. Findings showed that the Exercise Sports Top and the Lady Duke bras allowed the least amount of breast movement. (Author/CB)

  4. The Biomechanical Support of Eight Selected Sports Bras for Small, Medium and Large Breasted Women while Jogging.

    ERIC Educational Resources Information Center

    Lorentzen, Deana; Lawson, LaJean

    This study compared the biomechanical support offered by eight presently marketed sports bras for small-, medium-, and large-breasted women while jogging. Fifty-nine subjects were filmed while jogging on a treadmill in each of the bras and in the nude condition. The vertical displacement of the breast relative to the body during one average…

  5. Construction and Initial Validation of the Color-Blind Racial Attitudes Scale (CoBRAS).

    ERIC Educational Resources Information Center

    Neville, Helen A.; Lilly, Roderick L.; Duran, Georgia; Lee, Richard M.; Browne, LaVonne

    2000-01-01

    Describes development of a conceptually grounded scale to assess cognitive aspects of color-blind racial attitudes. Factor analysis suggests that the 3-factor model is a good fit of data. States that CoBRAS was positively related to other indexes of racial attitudes indicating that greater endorsement of color-blind racial attitudes was related to…

  6. Leishmania (Leishmania) hertigi in a porcupine (Coendou sp.) found in Brasília, Federal District, Brazil.

    PubMed

    Silva, Denise Amaro da; Madeira, Maria de Fatima; Barbosa Filho, Carlos José Lima; Schubach, Edvar Yuri Paheco; Barros, Juliana Helena da Silva; Figueiredo, Fabiano Borges

    2013-01-01

    Studies report the occurrence of Leishmania (Leishmania) hertigi in northern states of Brazil. In the present investigation, we describe the isolation of L. (L.) hertigi from a porcupine (Coendou sp.) found in Brasília, Federal District, center-west region of Brazil. During a study on canine visceral leishmaniasis conducted in the city of Brasília, Federal District, a porcupine was found dead on a public road. The animal was identified and fragments of intact skin and spleen were collected for isolation of parasite in the culture. This report of the occurrence of L. hertigi in another part of Brazil may help establish the distribution of this parasite in the country. Further studies are needed to better understand the role of L. hertigi in the pathology and pathogenesis of leishmaniasis and its survival in mammals and possible vectors.

  7. Leishmania (Leishmania) hertigi in a porcupine (Coendou sp.) found in Brasília, Federal District, Brazil.

    PubMed

    Silva, Denise Amaro da; Madeira, Maria de Fatima; Barbosa Filho, Carlos José Lima; Schubach, Edvar Yuri Paheco; Barros, Juliana Helena da Silva; Figueiredo, Fabiano Borges

    2013-01-01

    Studies report the occurrence of Leishmania (Leishmania) hertigi in northern states of Brazil. In the present investigation, we describe the isolation of L. (L.) hertigi from a porcupine (Coendou sp.) found in Brasília, Federal District, center-west region of Brazil. During a study on canine visceral leishmaniasis conducted in the city of Brasília, Federal District, a porcupine was found dead on a public road. The animal was identified and fragments of intact skin and spleen were collected for isolation of parasite in the culture. This report of the occurrence of L. hertigi in another part of Brazil may help establish the distribution of this parasite in the country. Further studies are needed to better understand the role of L. hertigi in the pathology and pathogenesis of leishmaniasis and its survival in mammals and possible vectors. PMID:23538497

  8. Complex I assembly function and fatty acid oxidation enzyme activity of ACAD9 both contribute to disease severity in ACAD9 deficiency

    PubMed Central

    Schiff, Manuel; Haberberger, Birgit; Xia, Chuanwu; Mohsen, Al-Walid; Goetzman, Eric S.; Wang, Yudong; Uppala, Radha; Zhang, Yuxun; Karunanidhi, Anuradha; Prabhu, Dolly; Alharbi, Hana; Prochownik, Edward V.; Haack, Tobias; Häberle, Johannes; Munnich, Arnold; Rötig, Agnes; Taylor, Robert W.; Nicholls, Robert D.; Kim, Jung-Ja; Prokisch, Holger; Vockley, Jerry

    2015-01-01

    Acyl-CoA dehydrogenase 9 (ACAD9) is an assembly factor for mitochondrial respiratory chain Complex I (CI), and ACAD9 mutations are recognized as a frequent cause of CI deficiency. ACAD9 also retains enzyme ACAD activity for long-chain fatty acids in vitro, but the biological relevance of this function remains controversial partly because of the tissue specificity of ACAD9 expression: high in liver and neurons and minimal in skin fibroblasts. In this study, we hypothesized that this enzymatic ACAD activity is required for full fatty acid oxidation capacity in cells expressing high levels of ACAD9 and that loss of this function is important in determining phenotype in ACAD9-deficient patients. First, we confirmed that HEK293 cells express ACAD9 abundantly. Then, we showed that ACAD9 knockout in HEK293 cells affected long-chain fatty acid oxidation along with Cl, both of which were rescued by wild type ACAD9. Further, we evaluated whether the loss of ACAD9 enzymatic fatty acid oxidation affects clinical severity in patients with ACAD9 mutations. The effects on ACAD activity of 16 ACAD9 mutations identified in 24 patients were evaluated using a prokaryotic expression system. We showed that there was a significant inverse correlation between residual enzyme ACAD activity and phenotypic severity of ACAD9-deficient patients. These results provide evidence that in cells where it is strongly expressed, ACAD9 plays a physiological role in fatty acid oxidation, which contributes to the severity of the phenotype in ACAD9-deficient patients. Accordingly, treatment of ACAD9 patients should aim at counteracting both CI and fatty acid oxidation dysfunctions. PMID:25721401

  9. "Radon Concentration Survey in Inner Rooms from Deputy Chamber and National Congress—Brasília/DF"

    NASA Astrophysics Data System (ADS)

    Nícoli, Ieda Gomes; Cardozo, Kátia Maria; de Azevedo Gouvea, Vandir

    2008-08-01

    Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasília—DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of 222Rn contents. Derived values, whose average value was about 73 Bq/m3, were all under maximum permissible limits for radon 200 Bq/m3, established by International Comission on Radiological Protection—ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Brasélia with effective participation of Nuclear Engineering Institute from CNEN—RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors.

  10. The small-scale urban reservoir fisheries of Lago Paranoá, Brasília, DF, Brazil.

    PubMed

    Walter, T; Petrere, M

    2007-02-01

    In many cases in large urban centers, which have appropriate waterbodies, small-scale fisheries are the only source of cheap protein for the poor. In Lago Paranoá, located in Brasília, the capital city of Brazil, fishing was studied by conducting interviews with 53 fishers filling in logbooks from March, 1999 to March, 2000 in three fishing communities. The fishers come from the poorest towns around Brasília, known as satellite-towns. They have been living there on average for 21.7 years (s = 9.6 years), their families have 4.9 members (s = 3.6) on average and 44.2% do not have a basic education. However, such characteristics are similar to the socioeconomic indices of the metropolis where they live. In spite of being illegal between 1966 and 2000, fishing generated an average monthly income of U 239.00 dollars (s = U 171.77 dollars). The Nile Tilapia Oreocrhromis niloticus is the main captured species (85% of a total number of landings in weight of 62.5 t.). Fishing is carried out in rowing boats, individually or in pairs. The fishing equipment used are gillnets and castnets. Gillnets were used actively, whereby the surface of the water is beaten with a stick to drive Tilapias towards nets as they have the ability to swim backwards. This fishing strategy was used in 64.7% of the fisheries, followed by castnets (31.1%) and by gillnets which were used less (4.2%). The fish is sold directly in the streets and fairs of the satellite-towns to middlemen or to bar owners. Three communities have different strategies in terms of fishing equipments, fishing spots and commercialization. Consequently, there are statistically significant differences in relation to the monthly income for each one of these communities.

  11. Socio-economic indicators and predisposing factors associated with traumatic dental injuries in schoolchildren at Brasília, Brazil: a cross-sectional, population-based study

    PubMed Central

    2014-01-01

    Background This study assessed the prevalence of traumatic dental injuries (TDI) and its association with sociodemographic and physical characteristics in the anterior permanent teeth of 12-year-old schoolchildren at the city of Brasília – DF, Brazil. Methods A cross-sectional, population-based study was conducted on a sample of 1,389 boys and girls aged 12 years, enrolled in public and private fundamental schools at the Administrative Region (RA) of Brasília, Brazil, from October 2011 to September 2012. The demographic details were achieved by a structured questionnaire. The study recorded the type of damage, the size of incisal overjet, and whether lip coverage was inadequate. Sociodemographic data included sex, income and educational level of the parents or caretakers. Results A total of 1118 schoolchildren were examined, yielding a response rate of 80.48%. The prevalence of TDI was 14.63% in public schools and 23.40% in private schools. The students did not differ according to sex, income and educational level of the parents or caretakers concerning the occurrence of traumas in permanent anterior teeth. Increased overjet and inadequate lip coverage were found to be important contributing factors for TDIs. Conclusion In conclusion, this study showed an expressive prevalence of TDI in 12-year-old in schoolchildren at Brasília DF, Brazil. Sex and educational level of the parents were not associated with trauma. The increased overjet and inadequate lip coverage were significantly associated with dental trauma. PMID:25037704

  12. Le syndrome des loges du bras: une complication inhabituelle de l'intoxication au monoxyde de carbone

    PubMed Central

    Chkoura, Khalid; Kechna, Hicham; Loutid, Jaouad; Ouzad, Omar; Cherradi, Toufiq; Hachimi, Moulay Ahmed

    2015-01-01

    Le monoxyde de carbone (CO) surnommé “Silent killer” par les Anglo-Saxons représente la première cause de mortalité par intoxication accidentelle ou volontaire en Europe comme aux États-Unis. Au Maroc, le centre anti poison a collecté entre 1991 et 2008, 12976 cas d'intoxication au monoxyde de carbone dont 98,7% étaient accidentelles. Cette intoxication est très exceptionnellement compliquée d'un syndrome de loge qui peut contribuer à une aggravation certaine du pronostic fonctionnel et vital quand il est ignoré ou dominé par d'autres symptômes en particulier neurologiques. Nous rapportons le cas d'un gardien de nuit qui a présenté un syndrome de loge particulier par sa localisation (bras) au cours d'une intoxication au CO qui a évolué favorablement. PMID:26301009

  13. Epidemiological characteristics of 778 patients who underwent surgical drainage of chronic subdural hematomas in Brasília, Brazil

    PubMed Central

    2013-01-01

    Background Chronic subdural hematomas (CSDHs) are common in neurosurgical practice. There are no publications that report large series of the epidemiological characteristics of this pathology in Brazil. The purpose is to describe a large series of surgical cases and analyze the epidemiological and clinical characteristics. Methods We retrospectively analyzed patients with CSDH admitted into Neurosurgical Services at the Hospital de Base do Distrito Federal, Brasília, Brazil from 2006 to 2011. Age, sex, clinical feature, etiology, surgical procedure, side, clinical outcome, and recurrence were reviewed. Statistical tests were used to analyze data, and P < 0.05 was considered statistically significant. Results The series included 778 patients. There were 643 (82.6%) male patients with a mean age of 64.3 ± 15.9 (range, 14–93) years. The principal symptom was headache (58.9%). The most frequent origin was a fall (282 cases, 36.2%), but the origin remained unclear in 281 (36.1%) patients. Mild head injury occurred in 540 (69.4%) cases. Burr holes with drainage were used as the surgical procedure in 96.5% patients, and 687 (88.3%) patients had a positive outcome. Mortality was 0%. Recurrence was observed in 42 cases. Conclusions The occurrence of CSDHs is more common in elderly men. Treatment with burr holes and drainage is a simple and safe method for treatment. In our experience, CSDH presents decreased morbidity and mortality. PMID:23452673

  14. Breasts and Bras

    MedlinePlus

    ... Kids Home How the Body Works Puberty & Growing Up Staying Healthy Recipes & Cooking Staying Safe Health Problems Illnesses & Injuries Health Problems of Grown Ups People, Places & Things That Help Feelings Q&A ...

  15. Thermobarometric and geochronologic constraints on the tectonic evolution of the southern Brasília Fold Belt, Brazil

    NASA Astrophysics Data System (ADS)

    Reno, B. L.; Brown, M.; Piccoli, P. M.; Trouw, R. A.; Kobayashi, K.; Usui, T.; Nakamura, E.

    2006-05-01

    The Brasília Fold Belt lies between the São Francisco, Amazonas and Paranapanema cratons in central Brazil. In the southern portion of this belt, the Andrelândia Group comprises a stack of nappes that record metamorphic conditions ranging from greenschist facies at the base to high pressure granulite facies at the top of the stack. Published conventional thermobarometric data indicate peak P-T conditions of ~1.3 GPa and ~900°C in the uppermost nappes, and the few published geochronologic data suggest an age of peak metamorphism around 630 Ma. Here we report new thermobarometry for the uppermost nappes calculated using the average P-T method in THERMOCALC, based on new analytical data from our own samples and literature data, in order compare published results based on conventional thermobarometry to results obtained using the average P-T method. In addition, we report new U-Pb zircon ages that constrain the timing of metamorphism in the uppermost nappes of the Andrelândia Group. Maximum average P-T conditions of 1.5±0.2 GPa and 1020±130°C were calculated for a mafic granulite in the uppermost Socorro --- Guaxupé Nappe, which compares to published results of ~1.1 GPa and ~890°C. The Três Pontas --- Varginha Nappe, immediately below the Socorro --- Guaxupé Nappe, yields an average P-T of 1.1±0.1 GPa and 880±40°C for literature data, compared with published results of ~1.3 GPa and ~730°C. In addition, our new analytical data from the Três Pontas --- Varginha Nappe yield P-T conditions comparable to the recalculated data, with typical peak P ranging from 0.9 to 1.2 GPa and T ranging from 750 to 880°C. These data suggest that the upper nappe was subjected to higher pressures than previously reported, and also may have been subjected to higher temperatures. For the Carmo da Cachoeira Nappe, immediately below the Três Pontas --- Varginha Nappe, we calculate P-T of 0.6 to 0.7 GPa and 520 to 580°C. For the Três Pontas --- Varginha Nappe, zircons were

  16. Factors associated with recidivism among adolescents girls in conflict with the law in an institution in Brasília, Federal District, Brazil.

    PubMed

    Gallassi, Andrea Donatti; dos Santos, Samantha Lima; Santos, Vagner Dos; Nakano, Eduardo Yoshio; Fischer, Benedikt; Galinkin, Ana Lúcia; Wagner, Gabriela Arantes

    2015-12-01

    Recidivism is a challenge for the Brazilian socio-educational system because it is associated with personal, social and environmental factors, especially among juvenile offenders. This study examined key characteristics and potential association with recidivism in 391 female adolescent offenders from a correctional institution in Brasília, Federal District, Brazil, between 2004 and 2011. Cross-sectional data on socio-demographics, drug use and offense characteristics from institutional information were examined. Associate factors with recidivism were examined using negative binomial regression analyses. 32.5% of offenders were recidivists at present admission and the mean frequency of recidivism among recidivists was 2.16. About half (53.6%) of the sample reported drug use. After the adjustment, recidivism was positively associated with: age; offender's drug use; residence status; offense type; and no family drug use. Factors associated with juvenile offenders' recidivism confirm findings from elsewhere, and should inform targeted interventions in Brazil.

  17. Factors associated with recidivism among adolescents girls in conflict with the law in an institution in Brasília, Federal District, Brazil.

    PubMed

    Gallassi, Andrea Donatti; dos Santos, Samantha Lima; Santos, Vagner Dos; Nakano, Eduardo Yoshio; Fischer, Benedikt; Galinkin, Ana Lúcia; Wagner, Gabriela Arantes

    2015-12-01

    Recidivism is a challenge for the Brazilian socio-educational system because it is associated with personal, social and environmental factors, especially among juvenile offenders. This study examined key characteristics and potential association with recidivism in 391 female adolescent offenders from a correctional institution in Brasília, Federal District, Brazil, between 2004 and 2011. Cross-sectional data on socio-demographics, drug use and offense characteristics from institutional information were examined. Associate factors with recidivism were examined using negative binomial regression analyses. 32.5% of offenders were recidivists at present admission and the mean frequency of recidivism among recidivists was 2.16. About half (53.6%) of the sample reported drug use. After the adjustment, recidivism was positively associated with: age; offender's drug use; residence status; offense type; and no family drug use. Factors associated with juvenile offenders' recidivism confirm findings from elsewhere, and should inform targeted interventions in Brazil. PMID:26872233

  18. Evidence of a wide spectrum of cardiac involvement due to ACAD9 mutations: Report on nine patients.

    PubMed

    Dewulf, Joseph P; Barrea, Catherine; Vincent, Marie-Françoise; De Laet, Corinne; Van Coster, Rudy; Seneca, Sara; Marie, Sandrine; Nassogne, Marie-Cécile

    2016-07-01

    Acyl-CoA dehydrogenase 9 (ACAD9) is a mitochondrial protein involved in oxidative phosphorylation complex I biogenesis. This protein also exhibits acyl-CoA dehydrogenase (ACAD) activity. ACAD9-mutated patients have been reported to suffer from primarily heart, muscle, liver, and nervous system disorders. ACAD9 mutation is suspected in cases of elevated lactic acid levels combined with complex I deficiency, and confirmed by ACAD9 gene analysis. At least 18 ACAD9-mutated patients have previously been reported, usually displaying severe cardiac involvement. We retrospectively studied nine additional patients from three unrelated families with a wide spectrum of cardiac involvement between the families as well as the patients from the same families. All patients exhibited elevated lactate levels. Deleterious ACAD9 mutations were identified in all patients except one for whom it was not possible to recover DNA. To our knowledge, this is one of the first reports on isolated mild ventricular hypertrophy due to ACAD9 mutation in a family with moderate symptoms during adolescence. This report also confirms that dilated cardiomyopathy may occur in conjunction with ACAD9 mutation and that some patients may respond clinically to riboflavin treatment. Of note, several patients suffered from patent ductus arteriosus (PDA), with one exhibiting a complex congenital heart defect. It is yet unknown whether these cardiac manifestations were related to ACAD9 mutation. In conclusion, this disorder should be suspected in the presence of lactic acidosis, complex I deficiency, and any cardiac involvement, even mild. PMID:27233227

  19. Evidence of a wide spectrum of cardiac involvement due to ACAD9 mutations: Report on nine patients.

    PubMed

    Dewulf, Joseph P; Barrea, Catherine; Vincent, Marie-Françoise; De Laet, Corinne; Van Coster, Rudy; Seneca, Sara; Marie, Sandrine; Nassogne, Marie-Cécile

    2016-07-01

    Acyl-CoA dehydrogenase 9 (ACAD9) is a mitochondrial protein involved in oxidative phosphorylation complex I biogenesis. This protein also exhibits acyl-CoA dehydrogenase (ACAD) activity. ACAD9-mutated patients have been reported to suffer from primarily heart, muscle, liver, and nervous system disorders. ACAD9 mutation is suspected in cases of elevated lactic acid levels combined with complex I deficiency, and confirmed by ACAD9 gene analysis. At least 18 ACAD9-mutated patients have previously been reported, usually displaying severe cardiac involvement. We retrospectively studied nine additional patients from three unrelated families with a wide spectrum of cardiac involvement between the families as well as the patients from the same families. All patients exhibited elevated lactate levels. Deleterious ACAD9 mutations were identified in all patients except one for whom it was not possible to recover DNA. To our knowledge, this is one of the first reports on isolated mild ventricular hypertrophy due to ACAD9 mutation in a family with moderate symptoms during adolescence. This report also confirms that dilated cardiomyopathy may occur in conjunction with ACAD9 mutation and that some patients may respond clinically to riboflavin treatment. Of note, several patients suffered from patent ductus arteriosus (PDA), with one exhibiting a complex congenital heart defect. It is yet unknown whether these cardiac manifestations were related to ACAD9 mutation. In conclusion, this disorder should be suspected in the presence of lactic acidosis, complex I deficiency, and any cardiac involvement, even mild.

  20. Geochemical signatures of metasedimentary rocks of high-pressure granulite facies and their relation with partial melting: Carvalhos Klippe, Southern Brasília Belt, Brazil

    NASA Astrophysics Data System (ADS)

    Cioffi, Caue Rodrigues; Campos Neto, Mario da Costa; da Rocha, Brenda Chung; Moraes, Renato; Henrique-Pinto, Renato

    2012-12-01

    High-grade metasedimentary rocks can preserve geochemical signatures of their sedimentary protolith if significant melt extraction did not occur. Retrograde reaction textures provide the main evidence for trapped melt in the rock fabrics. Carvalhos Klippe rocks in Southern Brasília Orogen, Brazil, present a typical high-pressure granulite assemblage with evidence of mica breakdown partial melting (Ky + Grt + Kfs ± Bt ± Rt). The metamorphic peak temperatures obtained by Zr-in-Rt and ternary feldspar geothermometers are between 850 °C and 900 °C. The GASP baric peak pressure obtained using grossular rich garnet core is 16 kbar. Retrograde reaction textures in which the garnet crystals are partially to totally replaced by Bt + Qtz ± Fsp intergrowths are very common in the Carvalhos Klippe rocks. These reactions are interpreted as a result of interactions between residual phases and trapped melt during the retrograde path. In the present study the geochemical signatures of three groups of Carvalhos Klippe metasedimentary rocks are analysed. Despite the high metamorphic grade these three groups show well-defined geochemical features and their REE patterns are similar to average compositions of post-Archean sedimentary rocks (PAAS, NASC). The high-pressure granulite facies Grt-Bt-Pl gneisses with immature arenite (wacke, arkose or lithic-arenite) geochemical signatures present in the Carvalhos Klippe are compared to similar rocks in amphibolite facies from the same tectonic framework (Andrelândia Nappe System). The similar geochemical signatures between Grt-Bt-Pl gneisses metamorphosed in high-pressure granulite facies and Grt-Bt-Pl-Qtz schists from the Andrelândia and Liberdade Nappes, with minimal to absent melting conditions, are suggestive of low rates of melt extraction in these high-grade rocks. The rocks with pelitic compositions most likely had higher melt extraction and even under such circumstances nevertheless tend to show REE patterns similar to

  1. The Caldas Novas dome, central Brazil: structural evolution and implications for the evolution of the Neoproterozoic Brası´lia belt

    NASA Astrophysics Data System (ADS)

    D'el-Rey Silva, Luiz José Homem; Wolf Klein, Percy Boris; Walde, Detlef Hans-Gert

    2004-10-01

    The Caldas Novas dome (Goiaás state, central Brazil) lies in the southern segment of the Neoproterozoic Brası´lia belt (center of the Tocantins Province) between the Goiás magmatic arc and the margin of the ancient São Francisco plate. The core of the dome comprises rocks of the Meso-Neoproterozoic Paranoá group (passive margin psamitic-pelitic sediments and subgreenschist facies) covered by a nappe of the Neoproterozoic Araxá group (backarc basin pelitic-psamitic sediments and volcanics of greenschist facies, bitotite zone). Hot underground waters that emerge along fractures in the Paranoá quartzite and wells in the Araxá schist have made the Caldas Novas dome an international tourist attraction. A recent detailed structural analysis demonstrates that the dome area was affected by a D 1-D 3 Brasiliano cycle progressive deformation in the ˜750-600 Ma interval (published U-Pb and Sm-Nd data). During event D 1, a pervasive layer-parallel foliation developed coeval the regional metamorphism. Event D 2 (intense F 2 isoclinal folding) was responsible for the emplacement of the nappe. D 1 and D 2 record a regime of simple shear (top-to-SE relative regional movement) due to a WNW-ESE subhorizontal compression ( σ1). Event D 3 records a WSW-ENE compression, during which the dome rose as a large-scale F 3 fold, possibly associated with a duplex structure at depth. During the dome's uplift, the layers slid back and down in all directions, giving way to gravity-slide folds and an extensional crenulation cleavage. A set of brittle fractures and quartz veins constitutes the record of a late-stage D 4 event important for understanding the thermal water reservoir.

  2. The Santa Terezinha-Campos Verdes emerald district, central Brazil: structural and Sm-Nd data to constrain the tectonic evolution of the Neoproterozoic Brası´lia belt

    NASA Astrophysics Data System (ADS)

    D'el-Rey Silva, Luiz José Homem; Barros Neto, Leonel de Souza

    2002-12-01

    Structural analysis coupled with Sm-Nd isotope data and a detailed description of the geology of the Santa Terezinha-Campos Verdes emerald district (Goiás State, Central Brazil) constrain the evolution of the Neoproterozoic Brası´lia belt. The area is composed of tectonic slices of Archean-Paleoproterozoic gneiss, a Meso-Neoproterozoic metavolcanic sedimentary sequence called the Santa Terezinha sequence, and crustal-derived intrusive rocks such as mylonitic (ortho)gneiss and a syntectonic porphyry granite. It underwent a Neoproterozoic greenschist facies polyphase ductile deformation (D 1-D 3). Structures indicate an event of rotational deformation along a typical frontal ramp dipping gently to the west (i.e. an event of simple shear with top to ESE relative regional movement due to a subhorizontal WNW-ESE compression). A Sm-Nd whole-rock isochron age of 577±77 Ma for the intrusive rocks constrains the timing of at least part of the deformation/metamorphism in the area. Primary and metamorphic planar structures (mainly D 1-D 2) strike SW-NE and dip at low to moderate angles to the NW in the northern part of the area. However, they gradually rotate to SSE in the central SE part, where the Peixe River synclinorium is developed. This synclinorium is also the nest of the D 2 sheath folds that control emerald ore shoots. The Santa Cruz dome is a basement-cored, major elliptic structure in the SW of the area. The Santa Terezinha sequence represents a back-arc basin that received input from the Neoproterozoic Goiás magmatic arc to the west and the São Francisco ancient continental margin to the east. The basal and upper sections of this sequence correlate, respectively, with other passive margin and back-arc sequences of the Brası´lia belt.

  3. Riboflavin-responsive oxidative phosphorylation complex I deficiency caused by defective ACAD9: new function for an old gene.

    PubMed

    Gerards, Mike; van den Bosch, Bianca J C; Danhauser, Katharina; Serre, Valérie; van Weeghel, Michel; Wanders, Ronald J A; Nicolaes, Gerry A F; Sluiter, Wim; Schoonderwoerd, Kees; Scholte, Hans R; Prokisch, Holger; Rötig, Agnès; de Coo, Irenaeus F M; Smeets, Hubert J M

    2011-01-01

    Mitochondrial complex I deficiency is the most common oxidative phosphorylation defect. Mutations have been detected in mitochondrial and nuclear genes, but the genetics of many patients remain unresolved and new genes are probably involved. In a consanguineous family, patients presented easy fatigability, exercise intolerance and lactic acidosis in blood from early childhood. In muscle, subsarcolemmal mitochondrial proliferation and a severe complex I deficiency were observed. Exercise intolerance and complex I activity was improved by a supplement of riboflavin at high dosage. Homozygosity mapping revealed a candidate region on chromosome three containing six mitochondria-related genes. Four genes were screened for mutations and a homozygous substitution was identified in ACAD9 (c.1594 C>T), changing the highly conserved arginine-532 into tryptophan. This mutation was absent in 188 ethnically matched controls. Protein modelling suggested a functional effect due to the loss of a stabilizing hydrogen bond in an α-helix and a local flexibility change. To test whether the ACAD9 mutation caused the complex I deficiency, we transduced fibroblasts of patients with wild-type and mutant ACAD9. Wild-type, but not mutant, ACAD9 restored complex I activity. An unrelated patient with the same phenotype was compound heterozygous for c.380 G>A and c.1405 C>T, changing arginine-127 into glutamine and arginine-469 into tryptophan, respectively. These amino acids were highly conserved and the substitutions were not present in controls, making them very probably pathogenic. Our data support a new function for ACAD9 in complex I function, making this gene an important new candidate for patients with complex I deficiency, which could be improved by riboflavin treatment. PMID:20929961

  4. Structural and lithological controls of gold-bearing veins associated with the Brasiliano-Pan African Orogeny: An example from the Buracão Area, Araí Group (Brasília Fold Belt, Brazil)

    NASA Astrophysics Data System (ADS)

    Pires, Gustavo Luiz Campos; Bongiolo, Everton Marques; Renac, Christophe; Nascimento, Débora Barros; Prado, Maurício

    2016-03-01

    The Buracão area, Central Brazil, comprises a group of structurally-controlled vein-type gold prospects, hosted in the metasedimentary Traíras Fm. of the Araí Group. This group records all tectonic stages of the Statherian taphrogenesis in Central Brazil and represents part of the Brasília Fold Belt (BFB) developed during the Neoproterozoic Brasiliano Orogeny. Three lithostratigraphic units were identified at the study area: two phyllitic and one composed of intercalation of quartzite and carbonaceous/sericite phyllites that hosted the Au mineralized vein systems. These units were metamorphosed to the biotite zone, greenschist facies. The high-grade mineralization (up to 31 g/t) occurs as subvertical zoned or massive veins with quartz, white mica, Fe-sulfides and Fe-oxides oriented in four main directions (i.e. N50°E; N°20E; N-S and E-W). Two deformational phases, each subdivided in two stages (D1a, D1b, D2a and D2b) were recognized in the study area. These deformational phases comprise different sets of structures, such as foliations, folds, faults, fractures and veins that represent regional deformational events on subordinated scale. The D1a and D1b stages represent the regional N-S trending thrust fronts and propagation folding developed during the evolution of W-E shortening, respectively. The D2a and D2b were correlated to the development and reactivation of regional-scale N- and NE-trending transpressive shear systems at different crustal levels, respectively. The gold-bearing quartz veins were developed during D2a stage as a complex shear fracture set according to a Riedel system, representing subordinated structures of the regional transpressive system. The structurally-controlled gold occurrences of the Buracão area is an example of orogenic vein-type gold mineralization developed during the Brasiliano-Pan African Orogeny at the BFB in Central Brazil. Our work suggests that this poorly studied part of BFB has good potential for additional high

  5. Neonatal multiorgan failure due to ACAD9 mutation and complex I deficiency with mitochondrial hyperplasia in liver, cardiac myocytes, skeletal muscle, and renal tubules.

    PubMed

    Leslie, Nancy; Wang, Xinjian; Peng, Yanyan; Valencia, C Alexander; Khuchua, Zaza; Hata, Jessica; Witte, David; Huang, Taosheng; Bove, Kevin E

    2016-03-01

    Complex I deficiency causes Leigh syndrome, fatal infant lactic acidosis, and neonatal cardiomyopathy. Mutations in more than 100 nuclear DNA and mitochondrial DNA genes miscode for complex I subunits or assembly factors. ACAD9 is an acyl-CoA dehydrogenase with a novel function in assembly of complex I; biallelic mutations cause progressive encephalomyopathy, recurrent Reye syndrome, and fatal cardiomyopathy. We describe the first autopsy in fatal neonatal lethal lactic acidosis due to mutations in ACAD9 that reduced complex I activity. We identified mitochondrial hyperplasia in cardiac myocytes, diaphragm muscle, and liver and renal tubules in formalin-fixed, paraffin-embedded tissue using immunohistochemistry for mitochondrial antigens. Whole-exome sequencing revealed compound heterozygous variants in the ACAD9 gene: c.187G>T (p.E63*) and c.941T>C (p.L314P). The nonsense mutation causes late infantile lethality; the missense variant is novel. Autopsy-derived fibroblasts had reduced complex I activity (53% of control) with normal activity in complexes II to IV, similar to reported cases of ACAD9 deficiency.

  6. The End of Alchemy? The Repudiation and Persistence of Chrysopoeia at the Académie Royale des Sciences in the Eighteenth Century.

    PubMed

    Principe, Lawrence M

    2014-01-01

    The general abandonment of serious endeavor toward metallic transmutation represents a major development in the history of chemistry, yet its exact causes and timing remain unclear. This essay examines the fate of chrysopoeia at the eighteenth-century Académie Royale des Sciences. It reveals a long-standing tension between Académie chemists, who pursued transmutation, and administrators, who tried to suppress it. This tension provides background for Etienne-François Geoffroy's 1722 paper describing fraudulent practices around transmutation. Although transmutation seems to disappear after Geoffroy's paper, manuscripts reveal that most of the institution's chemists continued to pursue it privately until at least the 1760s, long after widely accepted dates for the "demise of alchemy" in learned circles. PMID:26103750

  7. The End of Alchemy? The Repudiation and Persistence of Chrysopoeia at the Académie Royale des Sciences in the Eighteenth Century.

    PubMed

    Principe, Lawrence M

    2014-01-01

    The general abandonment of serious endeavor toward metallic transmutation represents a major development in the history of chemistry, yet its exact causes and timing remain unclear. This essay examines the fate of chrysopoeia at the eighteenth-century Académie Royale des Sciences. It reveals a long-standing tension between Académie chemists, who pursued transmutation, and administrators, who tried to suppress it. This tension provides background for Etienne-François Geoffroy's 1722 paper describing fraudulent practices around transmutation. Although transmutation seems to disappear after Geoffroy's paper, manuscripts reveal that most of the institution's chemists continued to pursue it privately until at least the 1760s, long after widely accepted dates for the "demise of alchemy" in learned circles.

  8. Analysis of p53 transactivation domain mutants reveals Acad11 as a metabolic target important for p53 pro-survival function

    PubMed Central

    Jiang, Dadi; LaGory, Edward L.; Brož, Daniela Kenzelmann; Bieging, Kathryn T.; Brady, Colleen A.; Link, Nichole; Abrams, John M.; Giaccia, Amato J.; Attardi, Laura D.

    2015-01-01

    SUMMARY The p53 tumor suppressor plays a key role in maintaining cellular integrity. In response to diverse stress signals, p53 can trigger apoptosis to eliminate damaged cells or cell-cycle arrest to enable cells to cope with stress and survive. However, the transcriptional networks underlying p53 pro-survival function are incompletely understood. Here, we show that in oncogenic-Ras-expressing cells, p53 promotes oxidative phosphorylation (OXPHOS) and cell survival upon glucose starvation. Analysis of p53 transcriptional activation domain mutants reveals that these responses depend on p53 transactivation function. Using gene expression profiling and ChIP-seq analysis, we identify several p53-inducible fatty acid metabolism-related genes. One such gene, Acad11, encoding a protein involved in fatty acid oxidation, is required for efficient OXPHOS and cell survival upon glucose starvation. This study provides new mechanistic insight into the pro-survival function of p53 and suggests that targeting this pathway may provide a strategy for therapeutic intervention based on metabolic perturbation. PMID:25704813

  9. When did Louis Pasteur present his memoir on the discovery of molecular chirality to the Académie des sciences? Analysis of a discrepancy.

    PubMed

    Gal, Joseph

    2008-11-01

    Louis Pasteur presented his historic memoir on the discovery of molecular chirality to the Académie des sciences in Paris on May 22nd, 1848. The literature, however, nearly completely ignores this date, widely claiming instead May 15th, 1848, which first surfaced in 1922 in Pasteur's collected works edited by his grandson Louis Pasteur Vallery-Radot. On May 21st, 1848, i.e., one day before Pasteur's presentation in Paris, his mother died in Arbois, eastern France. Informed at an unknown point in time that she was "very ill," Pasteur left for Arbois only after his presentation. Biographies of Pasteur by his son-in-law René Vallery-Radot or the grandson, and Pasteur's collected correspondence edited by the grandson are incomprehensibly laconic or silent about the historic presentation. While no definite conclusions are possible, the evidence strongly suggests a deliberate alteration of the record by the biographer relatives, presumably for fear of adverse public judgment of Pasteur for a real or perceived insensitivity to a grave family medical emergency. Such fear would have been in accord with their hagiographic portrayal of Pasteur, and the findings raise questions concerning the extent of their zeal in protecting his "demigod" image. Universal recognition of the true date of Pasteur's announcement of molecular chirality is long overdue.

  10. Amelioration de la precision d'un bras robotise pour une application d'ebavurage

    NASA Astrophysics Data System (ADS)

    Mailhot, David

    Process automation is a more and more referred solution when it comes to complex, tedious or even dangerous tasks for human. Flexibility, low cost and compactness make industrial robots very attractive for automation. Even if many developments have been made to enhance robot's performances, they still can not meet some industries requirements. For instance, aerospace industry requires very tight tolerances on a large variety of parts, which is not what robots were designed for at first. When it comes to robotic deburring, robot imprecision is a major problem that needs to be addressed before it can be implemented in production. This master's thesis explores different calibration techniques for robot's dimensions that could overcome the problem and make the robotic deburring application possible. Some calibration techniques that are easy to implement in production environment are simulated and compared. A calibration technique for tool's dimensions is simulated and implemented to evaluate its potential. The most efficient technique will be used within the application. Finally, the production environment and requirements are explained. The remaining imprecision will be compensated by the use of a force/torque sensor integrated with the robot's controller and by the use of a camera. Many tests are made to define the best parameters to use to deburr a specific feature on a chosen part. Concluding tests are shown and demonstrate the potential use of robotic deburring. Keywords: robotic calibration, robotic arm, robotic precision, robotic deburring

  11. Soil transference patterns on bras: Image processing and laboratory dragging experiments.

    PubMed

    Murray, Kathleen R; Fitzpatrick, Robert W; Bottrill, Ralph S; Berry, Ron; Kobus, Hilton

    2016-01-01

    In a recent Australian homicide, trace soil on the victim's clothing suggested she was initially attacked in her front yard and not the park where her body was buried. However the important issue that emerged during the trial was how soil was transferred to her clothing. This became the catalyst for designing a range of soil transference experiments (STEs) to study, recognise and classify soil patterns transferred onto fabric when a body is dragged across a soil surface. Soil deposits of interest in this murder were on the victim's bra and this paper reports the results of anthropogenic soil transfer to bra-cups and straps caused by dragging. Transfer patterns were recorded by digital photography and photomicroscopy. Eight soil transfer patterns on fabric, specific to dragging as the transfer method, appeared consistently throughout the STEs. The distinctive soil patterns were largely dependent on a wide range of soil features that were measured and identified for each soil tested using X-ray Diffraction and Non-Dispersive Infra-Red analysis. Digital photographs of soil transfer patterns on fabric were analysed using image processing software to provide a soil object-oriented classification of all soil objects with a diameter of 2 pixels and above transferred. Although soil transfer patterns were easily identifiable by naked-eye alone, image processing software provided objective numerical data to support this traditional (but subjective) interpretation. Image software soil colour analysis assigned a range of Munsell colours to identify and compare trace soil on fabric to other trace soil evidence from the same location; without requiring a spectrophotometer. Trace soil from the same location was identified by linking soils with similar dominant and sub-dominant Munsell colour peaks. Image processing numerical data on the quantity of soil transferred to fabric, enabled a relationship to be discovered between soil type, clay mineralogy (smectite), particle size and soil moisture content that would not have been possible otherwise. Soil type (e.g. Anthropogenic, gravelly sandy loam soil or Natural, organic-rich soil), clay mineralogy (smectite) and soil moisture content were the greatest influencing factors in all the dragging soil transference tests (both naked eye and measured properties) to explain the eight categories of soil transference patterns recorded. This study was intended to develop a method for dragging soil transference laboratory experiments and create a baseline of preliminary soil type/property knowledge. Results confirm the need to better understand soil behaviour and properties of clothing fabrics by further testing of a wider range of soil types and clay mineral properties. PMID:26679633

  12. Soil transference patterns on bras: Image processing and laboratory dragging experiments.

    PubMed

    Murray, Kathleen R; Fitzpatrick, Robert W; Bottrill, Ralph S; Berry, Ron; Kobus, Hilton

    2016-01-01

    In a recent Australian homicide, trace soil on the victim's clothing suggested she was initially attacked in her front yard and not the park where her body was buried. However the important issue that emerged during the trial was how soil was transferred to her clothing. This became the catalyst for designing a range of soil transference experiments (STEs) to study, recognise and classify soil patterns transferred onto fabric when a body is dragged across a soil surface. Soil deposits of interest in this murder were on the victim's bra and this paper reports the results of anthropogenic soil transfer to bra-cups and straps caused by dragging. Transfer patterns were recorded by digital photography and photomicroscopy. Eight soil transfer patterns on fabric, specific to dragging as the transfer method, appeared consistently throughout the STEs. The distinctive soil patterns were largely dependent on a wide range of soil features that were measured and identified for each soil tested using X-ray Diffraction and Non-Dispersive Infra-Red analysis. Digital photographs of soil transfer patterns on fabric were analysed using image processing software to provide a soil object-oriented classification of all soil objects with a diameter of 2 pixels and above transferred. Although soil transfer patterns were easily identifiable by naked-eye alone, image processing software provided objective numerical data to support this traditional (but subjective) interpretation. Image software soil colour analysis assigned a range of Munsell colours to identify and compare trace soil on fabric to other trace soil evidence from the same location; without requiring a spectrophotometer. Trace soil from the same location was identified by linking soils with similar dominant and sub-dominant Munsell colour peaks. Image processing numerical data on the quantity of soil transferred to fabric, enabled a relationship to be discovered between soil type, clay mineralogy (smectite), particle size and soil moisture content that would not have been possible otherwise. Soil type (e.g. Anthropogenic, gravelly sandy loam soil or Natural, organic-rich soil), clay mineralogy (smectite) and soil moisture content were the greatest influencing factors in all the dragging soil transference tests (both naked eye and measured properties) to explain the eight categories of soil transference patterns recorded. This study was intended to develop a method for dragging soil transference laboratory experiments and create a baseline of preliminary soil type/property knowledge. Results confirm the need to better understand soil behaviour and properties of clothing fabrics by further testing of a wider range of soil types and clay mineral properties.

  13. The white marble used in Brasília, a World Heritage and the capital of Brazil

    NASA Astrophysics Data System (ADS)

    Heloisa Barros de Oliveira Frascá, Maria

    2015-04-01

    Created as the Brazilian capital, in the central western part of Brazil, Brasilia is a definitive example of 20th century modernist urbanism. It was built in only four years, from 1956 to 1960, following the project of urban planner Lucio Costa and architect Oscar Niemeyer that intended that every element - from the layout of the residential and administrative districts (often compared to the shape of a bird in flight) to the symmetry of the buildings themselves - should be in harmony with the city's overall design. This description is from the World Heritage Centre, of Unesco, that nominated Brasilia as a Cultural Heritage Property in 1987. Most of the remarkable buildings designed Oscar Niemeyer, cited by Unesco, are around the Plaza of Three Powers, as the Planalto ("Plateau") Palace, the National Congress, the Supreme Court, the Cathedral, the National Theatre among others. Aside from the worldwide recognition of the architectonic value of these buildings, it is barely mentioned the expressive use of white marble as cladding. Very few are found in the literature about specification criteria, provenance, fixation method and conservation. According to Oscar Niemeyer Foundation, at this moment they know that the stone come from a supplier in the State of Rio de Janeiro. A preliminary research indicated that the marble used in most of Brasilia buildings are from the municipality of Italva, in the northwest of the State of Rio de Janeiro (DRM-RJ, 2012). In a study carried out by DRM-RJ, in 2003, it is mentioned two white marble commercialized as dimension stone in Italva: "Sparkling Marble" (SM) and "Italva White Marble" (IWM), respectively dolomite-calcite marble and dolomite marble. Their main characteristics are: bulk specific gravity: 2,792 kg/m3 (SM) and 2,852kg/m3 (IWM); water absorption: 0.08 % (SM) and 0.10 % (IWM); uniaxial compression strength: 84.3 MPa (SM) and 88.2 MPa (IWM); modulus of rupture: 9.92 MPa (SM) and 8.75 MPa (IWM); coefficient of linear dilatation: 6.0 10-3mm/m.oC (SM) and 5.2 10-3mm/m.oC (IWM). This data indicate that in spite the marble specification had not followed any technical or scientific criteria, or at least they are not easily available, they show good engineering properties and most of the slabs are still in the buildings. The preservation of this cultural world heritage is an urgent demand, as pointed by Unesco, and one of the main challenges is the stone conservation planning, to which is already necessary serious multidisciplinary technical and scientific studies. References DRM-RJ - DEPARTMENT OF MINERAL RESOURCES OF THE STATE OF RIO DE JANEIRO. (2003) Rio de Janeiro State dimension stones catalogue. DRM: Rio de Janeiro, 12 cards. DRM-RJ (2012) Mineral panorama of the State of Rio de Janeiro. DRM: Rio de Janeiro, 258p. (in Portuguese). UNESCO. World Heritage List. http://whc.unesco.org/en/list/445. (05/January/2015). FRASCÁ, M.H.B.O.; NAVARRO, F.C.; QUITETE, E.B. (2014) Staining tests for granitic stone conservation. In: Lollino, G. et al. (org.). Engineering Geology for Society and Territory - Preservation of cultural heritage. London: Springer International Publishing Switzerland, v. 8.

  14. Violence and youth in a territory of the Metropolitan Area of Brasília, Brazil: a socio-spatial approach.

    PubMed

    Moura, Leides Barroso Azevedo; Oliveira, Cesar de; Vasconcelos, Ana Maria Nogales

    2015-11-01

    Young people are impacted by the relations established in the context of multidimensional violence distributed in private and public spaces of urban areas. This article presents stories of violence suffered and committed by young individuals who live in Itapoã, part of the Metropolitan Area of Brasilia. This is a transversal and descriptive study, using a quantitative approach and a convenience sample of 190 young men and women aged 15 to 24 years. Forty-four questions previously validated were used as the data collection instrument. As for the experiences of violence, 51% reported having experienced some sort throughout life, and 24% in the last 12 months. Young people who have experienced some episode of violence throughout life also declared that the area or neighborhood where they live does not promote urban well-being for its residents (p <0.023); they expressed feelings compatible with depression (p = 001); and self-reported their health condition as bad (p = 000). The experiences of violence and youth vulnerabilities processes were discussed in the context of social injustice and limitations of human capabilities. PMID:26602717

  15. Correcting for the effects of pupil discontinuities with the ACAD method

    NASA Astrophysics Data System (ADS)

    Mazoyer, Johan; Pueyo, Laurent; N'Diaye, Mamadou; Mawet, Dimitri; Soummer, Rémi; Norman, Colin

    2016-07-01

    The current generation of ground-based coronagraphic instruments uses deformable mirrors to correct for phase errors and to improve contrast levels at small angular separations. Improving these techniques, several space and ground based instruments are currently developed using two deformable mirrors to correct for both phase and amplitude errors. However, as wavefront control techniques improve, more complex telescope pupil geometries (support structures, segmentation) will soon be a limiting factor for these next generation coronagraphic instruments. The technique presented in this proceeding, the Active Correction of Aperture Discontinuities method, is taking advantage of the fact that most future coronagraphic instruments will include two deformable mirrors, and is proposing to find the shapes and actuator movements to correct for the effect introduced by these complex pupil geometries. For any coronagraph previously designed for continuous apertures, this technique allow to obtain similar performance in contrast with a complex aperture (with segmented and secondary mirror support structures), with high throughput and flexibility to adapt to changing pupil geometry (e.g. in case of segment failure or maintenance of the segments). We here present the results of the parametric analysis realized on the WFIRST pupil for which we obtained high contrast levels with several deformable mirror setups (size, separation between them), coronagraphs (Vortex charge 2, vortex charge 4, APLC) and spectral bandwidths. However, because contrast levels and separation are not the only metrics to maximize the scientific return of an instrument, we also included in this study the influence of these deformable mirror shapes on the throughput of the instrument and sensitivity to pointing jitters. Finally, we present results obtained on another potential space based telescope segmented aperture. The main result of this proceeding is that we now obtain comparable performance than the coronagraphs previously designed for WFIRST. First result from the parametric analysis strongly suggest that the 2 deformable mirror set up (size and distance between them) have a important impact on the performance in contrast and throughput of the final instrument.

  16. NaNoWriMo in the AcadLib: A Case Study of National Novel Writing Month Activities in an Academic Library

    ERIC Educational Resources Information Center

    Watson, Alex P.

    2012-01-01

    The J. D. Williams Library at the University of Mississippi launched a pilot program during the 2010 National Novel Writing Month, hosting related events to determine community demand and how such efforts could be quantified. Using participant-submitted word counts and the event's own tools, researchers were able to ascertain that such events had…

  17. Factors Affecting Academic Resilience in Middle School Students: A Case Study (Factores que Afectan la Resiliencia Académica en Estudiantes de Bachillerato)

    ERIC Educational Resources Information Center

    Rojas Flórez, Luisa Fernanda

    2015-01-01

    This research was carried out with the purpose of identifying how and which risk and protective factors affect academic outcomes. The study explored how different family and individual environmental factors foster academic resilience. The exploratory study took place with a group of six students from a public school in Bogotá, Colombia. The school…

  18. Nursing Supplies

    MedlinePlus

    ... Stages Listen Español Text Size Email Print Share Nursing Supplies Page Content Article Body Throughout most of ... budget. (Nursing equipment also makes wonderful baby gifts.) Nursing Bras A well-made nursing bra that comfortably ...

  19. Importance of LA-ICP-MS Zircon Geochronology and Geochemistry in Determining the History of Magmatic Systems: Insights from the Graciosa A-type Province, Southern Brazil

    NASA Astrophysics Data System (ADS)

    Braun, S.; Gualda, G. A.; Bream, B. R.; Vlach, S. R.

    2010-12-01

    textural and geochemical evidence, we interpret these 3 age populations as being representative of inheritance (>620 Ma), magmatism (~581 Ma), and hydrothermal alteration (~540 Ma). In light of these results, it is not surprising that previous age determinations using whole-zircon TIMS U/Pb and whole-rock Rb/Sr found a wide range of ages. Our study highlights the benefits of in-situ LA-ICPMS zircon geochronology as a method to deconvolve the evolution of igneous provinces, and shows that adequate precision (~0.5%) can be achieved in favorable circumstances. 1 GAR Gualda & SRF Vlach (2007) Anais Acad. Bras. Ciências, 79: 405-430

  20. Developing Academic Literacy and Voice: Challenges Faced by a Mature ESL Student and Her Instructors (Desarrollo del discurso académico y la voz: retos de una estudiante de inglés como segunda lengua y sus profesores)

    ERIC Educational Resources Information Center

    Correa, Doris

    2010-01-01

    Drawing on critical, socio-cultural and sociolinguistic theories of writing, text and voice, this ethnographic study examines the challenges that a mature ESL student and her instructors in a university course on Spanish Language Media face as they co-construct a common understanding of academic literacy and voice in an undergraduate General…

  1. Publishing and Academic Writing: Experiences of Authors Who Have Published in "PROFILE" (Publicación y escritura académica: experiencias de autores que han publicado en "PROFILE")

    ERIC Educational Resources Information Center

    Cárdenas, Melba L.

    2014-01-01

    The increase in the publication of academic journals is closely related to the growing interest of research communities as well as of institutional policies that demand visibility of the work done by their staff through publications in highly-ranked journals. The purpose of this paper is to portray the experiences of some authors who published…

  2. Struggling Authorial Identity of Second Language University Academic Writers in Mexico (La lucha de identidad de escritores académicos universitarios de segunda lengua en México)

    ERIC Educational Resources Information Center

    Crawford, Troy; Mora Pablo, Irasema; Lengeling, M. Martha

    2016-01-01

    This paper explores the different factors that appear to affect the on-going construction of second language authorial identity in a professional academic environment in Mexico. Through narrative research methodology from a qualitative paradigm, the everyday struggles of two university professors to maintain their professional status in second…

  3. Teaching EFL Academic Writing in Colombia: Reflections in Contrastive Rhetoric (La enseñanza de escritura académica en Colombia: reflexiones en retórica contrastiva)

    ERIC Educational Resources Information Center

    Gómez, Juan D.

    2011-01-01

    This essay relates observations to the reasons that advanced students of English as a foreign language in Colombia struggle with English composition. It identifies some cultural, academic, and disciplinary influences that may obfuscate their assimilation of the conventions of written English. It concludes by proposing that the teaching of context…

  4. The "It's No Secret" bra drive: an example of collaborative practice.

    PubMed

    Bennett, Yvonne

    2015-01-01

    Evidence collection by sexual assault nurse examiners (SANEs) is a crucial part of the forensic medical examination. SANEs attempt to collect all possible evidence including swabs, slides, urine, blood, and clothing. Because biological evidence can be found on underwear, bras, and other clothing, the SANE often asks patients to relinquish these clothing items during the forensic medical examination. Some patients are reluctant to relinquish their bras, for varying reasons. The Riverside County Sexual Assault Multi-Disciplinary Team conducted a bra collection drive, in conjunction with Sexual Assault Awareness Month. The purpose of the bra drive was to enable the SANE to provide a replacement bra in exchange for the patient's bra, which may contain biological evidence. The community response was overwhelming and has already enabled the collection of bras from patients who were otherwise unwilling to give them up. PMID:25695211

  5. Cellulite

    MedlinePlus

    ... Part I. Pathophysiology. J Am Acad Dermatol . 2010 Mar;62(3):361-70. PMID: 20159304 www.ncbi. ... Advances and controversies. J Am Acad Dermatol . 2010 Mar;62(3):373-84. PMID: 20159305 www.ncbi. ...

  6. How I Manage Breast Problems in Athletes.

    ERIC Educational Resources Information Center

    Haycock, Christine E.

    1987-01-01

    This article reviews the anatomy of the breast and describes injuries and disorders that occur in both men and women, including runner's nipples, bicyclist's nipples, tumors, and trauma. Management of these problems and various types of sports bras are discussed. (Author/MT)

  7. Science and Human Behavior translated into Portuguese: Ciência e Comportamento Humano.

    PubMed Central

    Todorov, João Claudio

    2003-01-01

    Science and Human Behavior was translated to Portuguese as part of the effort to begin a psychology course at the University of Brasília 40 years ago; one of the many results of the first visit of Fred S. Keller to Brazil. The book has been used continuously in undergraduate courses in Brazil since 1967. PMID:14964714

  8. Quantitative trait loci mapping of heat tolerance in a doubled haploid population of broccoli using genotyping-by-sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broccoli is a cool weather vegetable crop with a vernalization requirement to initiate and maintain floral development. Breeding for heat tolerance in broccoli has the potential to both expand viable production areas and extend the growing season. A doubled haploid (DH) population of broccoli (Bras...

  9. Condition-dependent migratory behaviour of endangered Atlantic salmon smolts moving through an inland sea.

    PubMed

    Crossin, Glenn T; Hatcher, Bruce G; Denny, Shelley; Whoriskey, Kim; Orr, Michael; Penney, Alicia; Whoriskey, Frederick G

    2016-01-01

    The Bras d'Or Lake watershed of Cape Breton Island, Nova Scotia, Canada is a unique inland sea ecosystem, UNESCO Biosphere Reserve and home to a group of regionally distinct Atlantic salmon (Salmo salar) populations. Recent population decreases in this region have raised concern about their long-term persistence. We used acoustic telemetry to track the migrations of juvenile salmon (smolts) from the Middle River into the Bras d'Or Lake and, subsequently, into the Atlantic Ocean. Roughly half of the tagged smolts transited the Bras d'Or Lakes to the Atlantic Ocean, using a migration route that took them through the Gulf of St Lawrence's northern exit at the Strait of Belle Isle (∼650 km from the home river) towards feeding areas in the Labrador Sea and Greenland. However, a significant fraction spent >70 days in the Lakes, suggesting that this population has an alternative resident form, in which smolts limit their migrations within the Bras d'Or. Smolts in good relative condition (as determined from length-to-mass relationships) tended to be residents, whereas fish in poorer condition were ocean migrants. We also found a covarying effect of river temperature that helped to predict residence vs. ocean migration. We discuss these results relative to their bioenergetic implications and provide suggestions for future studies aimed at the conservation of declining salmon populations in Canada. PMID:27293765

  10. EXAMINING REGIONAL LAND USE CHANGE: THE COMMUNITY GROWTH MODEL (CGM)

    EPA Science Inventory

    The U. S. Environmental Protection Agency's Regional Vulnerability Assessment
    Program (ReV A) is designed to develop and demonstrate approaches to identify the ecosystems at the greatest risk from regional population growth and economic activity. <br>As part of this program, ...

  11. Relationships Among the Knowledge, Efficacy, and Practices Instrument, Color-Blind Racial Attitudes Scale, Deamonte Driver Survey, and Defining Issues Test 2.

    PubMed

    Behar-Horenstein, Linda S; Garvan, Cynthia W

    2016-03-01

    Concordance studies indicate the degree to which instruments measure the same or similar constructs or something different. The aims of this study were to identify the factor structure of the Deamonte Driver Survey and determine the relationship between the Deamonte Driver (a measure of social class stereotyping), the Defining Issues Test 2 (DIT2; a measure of ethical sensitivity), the Color-Blind Racial Attitudes Scale (CoBRAS; a measure of racial stereotyping), and the Knowledge, Efficacy, and Practices Instrument (KEPI; a measure of cultural competence). The results showed a three-factor solution for the Deamonte Driver Survey and significant relationships between CoBRAS and DIT2 subscales and between CoBRAS and Deamonte Driver subscales. Significant relationships between the measures and exploratory variables, underrepresented minority status, age, citizenship, marital status, political stance, English as a first language, and gender were found. The lack of a significant relationship between the KEPI and Deamonte Driver, DIT2, or CoBRAS subscales suggests that the KEPI is measuring a unique construct. These findings showed how these scales contributed to the assessment of cultural competence among dental students and faculty. PMID:26933112

  12. Condition-dependent migratory behaviour of endangered Atlantic salmon smolts moving through an inland sea

    PubMed Central

    Crossin, Glenn T.; Hatcher, Bruce G.; Denny, Shelley; Whoriskey, Kim; Orr, Michael; Penney, Alicia; Whoriskey, Frederick G.

    2016-01-01

    The Bras d’Or Lake watershed of Cape Breton Island, Nova Scotia, Canada is a unique inland sea ecosystem, UNESCO Biosphere Reserve and home to a group of regionally distinct Atlantic salmon (Salmo salar) populations. Recent population decreases in this region have raised concern about their long-term persistence. We used acoustic telemetry to track the migrations of juvenile salmon (smolts) from the Middle River into the Bras d’Or Lake and, subsequently, into the Atlantic Ocean. Roughly half of the tagged smolts transited the Bras d’Or Lakes to the Atlantic Ocean, using a migration route that took them through the Gulf of St Lawrence’s northern exit at the Strait of Belle Isle (∼650 km from the home river) towards feeding areas in the Labrador Sea and Greenland. However, a significant fraction spent >70 days in the Lakes, suggesting that this population has an alternative resident form, in which smolts limit their migrations within the Bras d’Or. Smolts in good relative condition (as determined from length-to-mass relationships) tended to be residents, whereas fish in poorer condition were ocean migrants. We also found a covarying effect of river temperature that helped to predict residence vs. ocean migration. We discuss these results relative to their bioenergetic implications and provide suggestions for future studies aimed at the conservation of declining salmon populations in Canada. PMID:27293765

  13. LETTER TO THE EDITOR ON FENITROTHION (TOXICOLOGY SCIENCES, 2001)

    EPA Science Inventory

    Dear Dr. Klaassen:

    We appreciate the opportunity to respond to Dr. Goodman's comments. <br>As noted by Dr. Goodman, the purpose of our study was to assess
    whether fenitrothion was an antiandrogen. Our interest in this issue
    was driven by the close structural simil...

  14. All about Menstruation (For Children)

    MedlinePlus

    ... Got Homework? Here's Help White House Lunch Recipes All About Menstruation KidsHealth > For Kids > All About Menstruation Print A A A Text Size ... Period Cramps When Will I Get My Period? All About Puberty Pads and Tampons Breasts and Bras ...

  15. INHIBITORY EFFECTS OF VOLATILE ORGANIC COMPOUNDS ON NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS.

    EPA Science Inventory

    INHIBITORY EFFECTS OF VOLATILE ORGANIC COMPOUNDS ON NEURONAL NICOTINIC ACETYLCHOLINE RECEPTORS. <br>A.S. Bale*; P.J. Bushnell; C.A. Meacham; T.J. Shafer
    Neurotoxicology Division, NHEERL, ORD, US Environmental Protection Agency, Research Triangle Park, NC, USA
    Toluene (TOL...

  16. What's Race Got to Do with It? Preservice Teachers and White Racial Identity

    ERIC Educational Resources Information Center

    Peters, Terri; Margolin, Marcia; Fragnoli, Kristi; Bloom, Diane

    2016-01-01

    This study examined changes in student teachers' White racial identity and color-blindness (using scores on the WRCDS-R and CoBRAS), as well as their perceptions of working with students of color, following a semester of student teaching in diverse classrooms. Paired samples t-tests demonstrated student teachers were more color-blind about…

  17. Relationships Among the Knowledge, Efficacy, and Practices Instrument, Color-Blind Racial Attitudes Scale, Deamonte Driver Survey, and Defining Issues Test 2.

    PubMed

    Behar-Horenstein, Linda S; Garvan, Cynthia W

    2016-03-01

    Concordance studies indicate the degree to which instruments measure the same or similar constructs or something different. The aims of this study were to identify the factor structure of the Deamonte Driver Survey and determine the relationship between the Deamonte Driver (a measure of social class stereotyping), the Defining Issues Test 2 (DIT2; a measure of ethical sensitivity), the Color-Blind Racial Attitudes Scale (CoBRAS; a measure of racial stereotyping), and the Knowledge, Efficacy, and Practices Instrument (KEPI; a measure of cultural competence). The results showed a three-factor solution for the Deamonte Driver Survey and significant relationships between CoBRAS and DIT2 subscales and between CoBRAS and Deamonte Driver subscales. Significant relationships between the measures and exploratory variables, underrepresented minority status, age, citizenship, marital status, political stance, English as a first language, and gender were found. The lack of a significant relationship between the KEPI and Deamonte Driver, DIT2, or CoBRAS subscales suggests that the KEPI is measuring a unique construct. These findings showed how these scales contributed to the assessment of cultural competence among dental students and faculty.

  18. Science and Human Behavior translated into Portuguese: Ciência e Comportamento Humano.

    PubMed

    Todorov, João Claudio

    2003-11-01

    Science and Human Behavior was translated to Portuguese as part of the effort to begin a psychology course at the University of Brasília 40 years ago; one of the many results of the first visit of Fred S. Keller to Brazil. The book has been used continuously in undergraduate courses in Brazil since 1967.

  19. Precocious Puberty (For Parents)

    MedlinePlus

    ... or pubic or underarm hair. The physical changes boys and girls go through during puberty are usually evident to ... About Puberty Understanding Puberty Acne All About Menstruation Boys and Puberty Breasts and Bras Girls and Puberty Word! Puberty Growth Disorders Thyroid Disorders ...

  20. Differences between Belgian and Brazilian Group A Streptococcus Epidemiologic Landscape

    PubMed Central

    Smeesters, Pierre Robert; Vergison, Anne; Campos, Dioclécio; de Aguiar, Eurico; Deyi, Veronique Yvette Miendje; Van Melderen, Laurence

    2006-01-01

    Background Group A Streptococcus (GAS) clinical and molecular epidemiology varies with location and time. These differences are not or are poorly understood. Methods and Findings We prospectively studied the epidemiology of GAS infections among children in outpatient hospital clinics in Brussels (Belgium) and Brasília (Brazil). Clinical questionnaires were filled out and microbiological sampling was performed. GAS isolates were emm-typed according to the Center for Disease Control protocol. emm pattern was predicted for each isolate. 334 GAS isolates were recovered from 706 children. Skin infections were frequent in Brasília (48% of the GAS infections), whereas pharyngitis were predominant (88%) in Brussels. The mean age of children with GAS pharyngitis in Brussels was lower than in Brasília (65/92 months, p<0.001). emm-typing revealed striking differences between Brazilian and Belgian GAS isolates. While 20 distinct emm-types were identified among 200 Belgian isolates, 48 were found among 128 Brazilian isolates. Belgian isolates belong mainly to emm pattern A–C (55%) and E (42.5%) while emm pattern E (51.5%) and D (36%) were predominant in Brasília. In Brasília, emm pattern D isolates were recovered from 18.5% of the pharyngitis, although this emm pattern is supposed to have a skin tropism. By contrast, A–C pattern isolates were unfrequently recovered in a region where rheumatic fever is still highly prevalent. Conclusions Epidemiologic features of GAS from a pediatric population were very different in an industrialised country and a low incomes region, not only in term of clinical presentation, but also in terms of genetic diversity and distribution of emm patterns. These differences should be taken into account for designing treatment guidelines and vaccine strategies. PMID:17183632

  1. Exploring Conceptions about Writing and Learning: Undergraduates' Patterns of Beliefs and the Quality of Academic Writing (Acercamiento a las concepciones sobre la escritura y el aprendizaje: patrones de creencias de los universitarios y la calidad de su redacción académica)

    ERIC Educational Resources Information Center

    Martínez-Fernández, J. R.; Corcelles, M.; Bañales, G.; Castelló, M.; Gutiérrez-Braojos, C.

    2016-01-01

    Introduction: In this study, the conceptions of learning and writing of a group of undergraduates enrolled in a teacher education programme were identified. The relationship between them were analysed, and a set of patterns of beliefs about learning and writing were defined. Finally, the relation between these patterns and the quality of a text…

  2. The Design of a Rubric to Evaluate Laboratory Reports in Astronomy: Academic Literacy in the Disciplines (El diseño de una rúbrica para evaluar informes de laboratorio en Astronomía: la alfabetización académica en las disciplinas)

    ERIC Educational Resources Information Center

    Arancibia Aguilera, María Cristina

    2014-01-01

    A rubric was developed to evaluate laboratory reports written by undergraduate students of astronomy and astrophysics from Universidad Católica de Chile. The process of elaboration, peer validation, and application of the rubric to the evaluation of written tasks extended from August 2011 to August 2012. The instrument proved to be effective as an…

  3. Promoting Tenth Graders' Reading Comprehension of Academic Texts in the English Class (Promoción de la comprensión de lectura de textos académicos de estudiantes de grado décimo en la clase de inglés)

    ERIC Educational Resources Information Center

    Quiroga Carrillo, Claudia

    2010-01-01

    This article reports on an action research project conducted in a public school in Bogotá, Colombia, with tenth grade students. We decided to develop it because of the students' needs as well as the em phasis of the PEI (Proyecto Educativo Institucional = School Institutional Project), which is based on the requisite of improving reading…

  4. Unraveling Ages of Discrete Cryptic Events During Polyphase Orogenesis in SE Brazil

    NASA Astrophysics Data System (ADS)

    Brown, M.; Reno, B. L.; Piccoli, P. M.; Trouw, R. A.

    2007-12-01

    The Neoproterozoic assembly of cratons in eastern Brazil is recorded by the successive Brasília, Ribeira and Buzios subduction-to-collision orogenic events in the intervals ca. 660-605 Ma (Reno et al., Frontiers in Mineral Sciences, abstract, 2007), ca. 580-550 Ma (Heilbron & Machado, Precambrian Res., 2003) and ca. 525- 505 Ma (Schmitt et al., Precambrian Res., 2004), respectively. The southern Brasília Belt displays characteristics of a passive margin in the east and an accretionary orogen in the west prior to terminal collision and final emplacement of the ENE-verging nappes. In the southern Brasília Belt, peak temperatures of 800-950 C are recorded, whereas in the Ribeira and Buzios Belts peak temperatures register around 780 C. Cryptic thermal overprinting by the younger events on the older orogenic belts is demonstrated by monazite age data from these Brasiliano-age belts in southeast Brazil. In the southern-most portion of the southern Brasília Belt, a SSE-plunging mineral elongation lineation and the occurrence of sillimanite represent macroscopic structural and petrologic evidence, respectively, of tectonic overprinting imposed during the Ribeira Orogeny. Comprehensive dating of monazite using the electron probe microanalysis method from throughout the southern-most Brasília Belt indicates widespread Ribeira-age (580-530 Ma) monazite growth, even tens of km north of the sillimanite-out isograd. The Buzios Belt lies outboard of the Ribera Belt; monazite from Ribera Belt migmatitic metapelites records Buzios-age growth. Monazite dates from the Ribeira belt determined using the electron probe microanalysis method were culled by chemical zone within individual grains. Exploratory data analysis (see Reno et al., Fall AGU, 2007) reveals distinct Ribeira-age (553-533 Ma) cores and Buzios-age (530-505 Ma) rims in monazite from rocks with no petrologic evidence of overprinting. Monazite grains likely grew during the Ribeira Orogeny, and were either partially

  5. The angiotensin converting enzyme inhibitor, captopril, prevents the hyperactivity and impulsivity of neurokinin-1 receptor gene 'knockout' mice: sex differences and implications for the treatment of attention deficit hyperactivity disorder.

    PubMed

    Porter, Ashley J; Pillidge, Katharine; Grabowska, Ewelina M; Stanford, S Clare

    2015-04-01

    Mice lacking functional neurokinin-1 receptors (NK1R-/-) display behavioural abnormalities resembling attention deficit hyperactivity disorder (ADHD): locomotor hyperactivity, impulsivity and inattentiveness. The preferred ligand for NK1R, substance P, is metabolised by angiotensin converting enzyme (ACE), which forms part of the brain renin angiotensin system (BRAS). In view of evidence that the BRAS modulates locomotor activity and cognitive performance, we tested the effects of drugs that target the BRAS on these behaviours in NK1R-/- and wildtype mice. We first tested the effects of the ACE inhibitor, captopril, on locomotor activity. Because there are well-established sex differences in both ADHD and ACE activity, we compared the effects of captopril in both male and female mice. Locomotor hyperactivity was evident in male NK1R-/- mice, only, and this was abolished by treatment with captopril. By contrast, male wildtypes and females of both genotypes were unaffected by ACE inhibition. We then investigated the effects of angiotensin AT1 (losartan) and AT2 (PD 123319) receptor antagonists on the locomotor activity of male NK1R-/- and wildtype mice. Both antagonists increased the locomotor activity of NK1R-/- mice, but neither affected the wildtypes. Finally, we tested the effects of captopril on the performance of male NK1R-/- and wildtype mice in the 5-choice serial reaction-time task (5-CSRTT) and found that ACE inhibition prevented the impulsivity of NK1R-/- mice. These results indicate that certain behaviours, disrupted in ADHD, are influenced by an interaction between the BRAS and NK1R, and suggest that ACE inhibitors could provide a novel treatment for this disorder.

  6. Hydrology Section Executive Committee minutes

    NASA Astrophysics Data System (ADS)

    Mercer, James W.

    The AGU Hydrology Section Executive Committee Meeting was called to order at approximately 4 P.M. on Monday, December 8, 1986 by Marshall Moss. In attendance were George Pinder, Allan Freeze, Jim Mercer, Ron Cummings, Ken Bencala, Jim Wallis, Simon Ince, Jack Stone, Jeff Dozier, Don Nielson, Ivan Johnson, John Wilson, Helen Peters, Jurate Landwehr, Karen Prestegaard, Soroosh Sorooshian, Jery Stedinger, Peter Kitanidis, Rafael Bras, and Waldo Smith.

  7. Los Alamos National Laboratory

    SciTech Connect

    Dogliani, Harold O

    2011-01-19

    The purpose of the briefing is to describe general laboratory technical capabilities to be used for various groups such as military cadets or university faculty/students and post docs to recruit into a variety of Los Alamos programs. Discussed are: (1) development and application of high leverage science to enable effeictive, predictable and reliability outcomes; (2) deter, detect, characterize, reverse and prevent the proliferation of weapons of mass destruction and their use by adversaries and terrorists; (3) modeling and simulation to define complex processes, predict outcomes, and develop effective prevention, response, and remediation strategies; (4) energetic materials and hydrodynamic testing to develop materials for precise delivery of focused energy; (5) materials cience focused on fundamental understanding of materials behaviors, their quantum-molecular properties, and their dynamic responses, and (6) bio-science to rapidly detect and characterize pathogens, to develop vaccines and prophylactic remedies, and to develop attribution forensics.

  8. Effect of intensive functional electrical stimulation therapy on upper-limb motor recovery after stroke: case study of a patient with chronic stroke.

    PubMed

    Kawashima, Noritaka; Popovic, Milos R; Zivanovic, Vera

    2013-01-01

    Objectif : Cette étude, motivée par un essai clinique randomisé qui démontrait que la thérapie par stimulation électrique fonctionnelle (FES) pouvait redonner la fonction volontaire du bras et de la main chez les patients qui avaient subi un AVC grave, a été conçue pour examiner les changements neuromusculaires aux membres supérieurs à la suite d'une thérapie intensive par FES comprenant une série de mouvements spécifiques du bras ainsi qu'une combinaison de séances de FES préprogrammées et de mouvements assistés. Méthode : La patiente, une femme de 22 ans qui avait subi un AVC hémorragique 2 ans plus tôt, a été traitée grâce à une thérapie par FES, à raison de 2 séances quotidiennes d'une heure chacune, pendant 12 semaines pour un total de 108 séances de traitement. Résultats : Bien que la contraction volontaire maximale des muscles de la portion supérieure du bras n'ait pas montré d'amélioration notable, la capacité d'amorcer et d'arrêter la contraction musculaire a augmenté pour un certain nombre de muscles des membres supérieurs (soit d'environ 5 à 15 % de la contraction musculaire maximale des mêmes muscles dans le bras moins affecté). Une réduction de la spasticité du bras a aussi été observée, notamment par la réduction du réflexe H dans le muscle fléchisseur du poignet (de 82,1 % à 45,0 % du Hmax/Mmax) et par une baisse des pointages obtenus à l'échelle d'Ashworth modifiée (de 3 à 2 pour la main, et de 4 à 3 pour le bras). La coordination entre les articulations de l'épaule et du coude au cours d'un test qui consistait à dessiner des cercles s'est améliorée considérablement pendant la thérapie par FES : la patiente n'était pas en mesure de tracer un cercle au départ, mais elle a pu le faire couramment après avoir reçu son congé. Conclusion : Des améliorations à la fonction des membres supérieurs observées chez les personnes ayant subi un AVC grave à la suite d'une th

  9. Friedreich ataxia in Acadian families from eastern Canada: Clinical diversity with conserved haplotypes

    SciTech Connect

    Richter, A.; Poirier, J.; Mercier, J.

    1996-09-06

    The gene for Friedreich ataxia (FRDA), an autosomal-recessive neurodegenerative disease, remains elusive. The current candidate region of about 150 kb lies between loci FR2 and F8101 near the D9S15/D9S5 linkage group at 9q13-21.1. Linkage homogeneity between classical FRDA and a milder, slowly progressive Acadian variant (FRDA-Acad) has been demonstrated. An extended D9S15-D9S5 haplotype (C6) predominates in FRDA-Acad chromosomes from Louisiana. We studied 10 Acadian families from New Brunswick, Canada. In eight families, affected individuals conformed to the clinical description of FRDA-Acad; in one, 2 sibs presented with spastic ataxia (SPA-Acad). In the last family, 2 sibs had FRDA-Acad, and one had SPA-Acad. We found that SPA-Acad is linked to the FRDA gene region. The C6 haplotype and a second major haplotype (137) were identified. The same ataxia-linked haplotypes segregated with both FRDA-Acad and SPA-Acad in two unrelated families. The parental origins of these haplotypes were different. Our observation of different phenotypes associated with the same combination of haplotypes may point to the influence of the parent of origin on gene expression, indicate the effect of modifier genes, or reflect the presence of different mutations on the same haplotype. Our findings underline the need to investigate families with autosomal-recessive ataxias for linkage to the FRDA region, despite lack of key diagnostic manifestations such as cardiomyopathy or absent deep-tendon reflexes. 28 refs., 4 figs., 3 tabs.

  10. [The negative consequences of the joint session of the 2 Academies in Soviet biological psychiatry].

    PubMed

    Kostandov, E A

    1990-12-01

    The liquidation of the scientific school in the brain pathology based by distinguished psychiatrist A. S. Shmar'ian, serves as an example of the negative role in the development of Soviet psychiatry played by the joint session of the USSR Acad. Sci. and Acad. Med. Sci. dedicated to the problems of I. P. Pavlov's physiological theory (June-July, 1950), and the joint session of the Presidium of the USSR Acad. Med. Sci. and the National Society of Neurologists and Psychiatrists (October, 1951). The absurd fight against dissidence in science harmed the studies in neuropsychiatry, where Soviet school had been among the most advanced world schools.

  11. River dynamics and landscape evolution in La Réunion Island: insights from luminescence dating

    NASA Astrophysics Data System (ADS)

    Farvacque, Manon; Valla, Pierre

    2016-04-01

    Tropical volcanic islands are natural laboratories to investigate the competition between volcanic construction (lava eruptions) and erosional destruction (extreme climatic events) in long-term landscape evolution. In La Réunion Island (Indian Ocean), the present day topography of the Piton des Neiges results from these competing processes. It presents three large-scale excavations called "cirques" that have been significantly eroded since the latest eruptive events but whose origin and formation time are still unclear. Indeed, the morphologic evolution of the Piton des Neiges is mostly known from K-Ar dating of lava flows and associated reconstructions of post-eruption eroded volumes. However, involved erosion processes and their rates through time remain poorly constrained, making it difficult to understand the geomorphic response to volcanic activity in this setting. Here, we focus on the "Bras de Cilaos" river that drains the "Cilaos cirque" (southern part of the Piton des Neiges). The Cilaos cirque has been first excavated between 140-180 ka [1], and it has been filled again during a late-stage eruptive event at ~145 ka [2] that also entirely filled the Bras de Cilaos valley. Alternatively, some studies have proposed that the Cilaos cirque and the Bras de Cilaos have been more recently filled by an eruption event at ~70 ka [3]. The Bras de Cilaos river is characterized by high relief (400-650 m) with no remaining evidence for these late eruptive events, showing significant incision and efficient fluvial erosion/transport processes after lava emplacement. In its downstream part, it presents thick alluvial deposits preserved along its riverbanks. The presence of such deposits may provide important constraints on the river dynamics and especially its response to the latest eruption events. However this requires establishing a tight temporal framework for these sediment archives. We thus sampled five different sedimentary sequences along the river to date their

  12. A conceptual design for the attitude control and determination system for the Magnetosphere Imager spacecraft

    NASA Technical Reports Server (NTRS)

    Polites, M. E.; Carrington, C. K.

    1995-01-01

    This paper presents a conceptual design for the attitude control and determination (ACAD) system for the Magnetosphere Imager (Ml) spacecraft. The MI is a small spin-stabilized spacecraft that has been proposed for launch on a Taurus-S expendable launch vehicle into a highly-ellipdcal polar Earth orbit. Presently, launch is projected for 1999. The paper describes the MI mission and ACAD requirements and then proposes an ACAD system for meeting these requirements. The proposed design is low-power, low-mass, very simple conceptually, highly passive, and consistent with the overall MI design philosophy, which is faster-better-cheaper. Still, the MI ACAD system is extremely robust and can handle a number of unexpected, adverse situations on orbit without impacting the mission as a whole. Simulation results are presented that support the soundness of the design approach.

  13. Genetics Home Reference: leptin receptor deficiency

    MedlinePlus

    ... leptin receptor gene causes obesity and pituitary dysfunction. Nature. 1998 Mar 26;392(6674):398-401. Citation ... and human weight regulation: lessons from experiments of nature. Ann Acad Med Singapore. 2009 Jan;38(1): ...

  14. Geographic variation in migration chronology and winter distribution of midcontinent greater white-fronted geese

    USGS Publications Warehouse

    Ely, Craig R.; Nieman, Daniel J.; Alisauskas, Ray T.; Schmutz, Joel A.; Hines, James E.

    2013-01-01

    We evaluated spatial and temporal differences in migratory behavior among different breeding groups of midcontinent greater white-fronted geese (Anser albifrons) using band-recovery data and observations of neck collared geese during migration and winter. Birds from different breeding areas were initially delineated by geographic distance into 6 banding reference areas (BRAs): 1) interior Alaska, 2) North Slope of Alaska, 3) western Northwest Territories (NWT), 4) western Nunavut, 5) central Nunavut, and 6) eastern Nunavut. The banding groups also differed by breeding habitat, with geese from interior Alaska nesting in the boreal forest (taiga), and all other groups breeding in tundra habitats. Geese from interior Alaska migrated earlier during autumn, and were more likely to winter farther south (in Mexico) than geese from other breeding areas. Geese banded in central and eastern Nunavut (Queen Maud Gulf and Inglis River) wintered farther east (in Louisiana) than geese from other breeding areas. Small-scale (within-state) geographic segregation of wintering flocks was evidenced by the recent (post-1990) nearly exclusive use of a new wintering area in north central Texas by geese from interior Alaska. Segregation among BRAs was also apparent in Mexico, where taiga geese were found predominantly in the central Highlands (states of Zacatecas and Durango), whereas tundra geese mostly used states along the Gulf Coast (primarily Tamaulipas). Interior Alaska birds initiated spring migration earlier than geese from other areas, and were more likely than others to stop in the Rainwater Basin of Nebraska, a region where cholera outbreaks periodically kill thousands of geese. Geese from interior Alaska were the first to arrive at spring staging areas in prairie Canada where BRAs exhibited spatial delineation (a longitudinal cline) in relation to breeding areas. Our results show significant geographic and temporal variation among taiga and tundra breeding cohorts during

  15. Pb and O isotopic constraints on the source of granitic rocks from Cape Breton Island, Nova Scotia, Canada

    USGS Publications Warehouse

    Ayuso, R.A.; Barr, S.M.; Longstaffe, F.J.

    1996-01-01

    Pb isotopic compositions of leached feldspars from twenty-three plutons in Cape Breton Island can be divided into two groups: anorthosite, syenite, and granite in the Blair River Complex, which have the least radiogenic compositions on the Island, and granitic rocks from terranes (Aspy, Bras d'Or, and Mira) to the south. Pb isotopic data for the Blair River Complex (206Pb/204Pb = 17.399-18.107; 207Pb/204Pb = 15.505-15.560; 208Pb/204Pb = 36.689-37.733) are consistent with an old source region ultimately derived from the mantle and contaminated by sialic crust. Oxygen isotopic compositions of syenite in the Blair River Complex (??18O = +8.0 to +8.5 permil) are slightly higher than anorthosite (+7.0 to +8.3 permil); a Silurian granite in the Blair River Complex has ??18O = +7.5 permil. Cambrian to Devonian plutons in the Aspy, Bras d'Or, and Mira terranes are more radiogenic (206Pb/204Pb = 18.192-18.981; 207Pb/204Pb = 15.574-15.712; 208Pb/ 204Pb =37.815-38.936) than the Blair River Complex and were generated from source regions having a predominant crustal Pb signature (high ??). The ??18O values of granites and granodiorites in the Aspy terrane (+7.5 to +9.2 permil; avg = +8.6 permil) and Bras d'Or (+3.7 to +11.3 permil; avg = +9.4 permil) are also consistent with involvement of sialic crust. Many Late Proterozoic granites from the Mira terrane have anomalously low ??18O values (+0.2 to +5.9 permil), perhaps produced from protoliths that had undergone hydrothermal alteration prior to melting. Paleozoic granitic rocks from the Aspy, Bras d'Or, and Mira terranes cannot be uniquely distinguished on the basis of their Pb and O isotopic compositions. The granitic rocks could have been generated during terrane amalgamation from combinations of unradiogenic (Grenville-like) and more radiogenic (Avalon-like) sources.

  16. Cassava in South America, Brazil's contribution and the lesson to be learned from India.

    PubMed

    Nassar, Nagib M A

    2006-11-30

    South America is responsible for about half of the cassava world production. In the 1970's productivity of the crop on the continent was about 15 ton/ha, and dropped continuously until reaching 12 ton/ha in 2004. India's productivity of cassava increased from 10 ton/ha in the 1970's to 28 ton/ha in 2004. Brazil contributed significantly to improving cassava crops through the Instituto Agronômico de Campinas in the 1960's and 1970's. The Universidade de Brasília released high-protein content hybrids, apomictic clones and explored the potential of indigenous landraces.

  17. Hydrology Section Executive Committee Minutes

    NASA Astrophysics Data System (ADS)

    Johnson, A. Ivan

    The Hydrology Section Executive Committee (EC) convened at 8:20 A.M. on May 28, 1985, in Room 311 of the Convention Center in Baltimore, Md. The meeting was chaired by Hydrology Section President R. Allan Freeze. Section President-Elect Marshall Moss kept the minutes in the absence of the Section Secretary Thomas Maddock III. Also in attendance were William Back, Rafael Bras, Stephen Burges, Jerry Cohon, Ron Cummings, David Dawdy, Jacques Delleur, Leonard Konikow, Jurate Landwehr, Fred Molz, Don Nielsen, Joyce Peters, Karen Prestegaard, Tom Schmugge, Waldo Smith, Jery Stedinger, and Eric Wood.

  18. Characterization of Novel Acyl Coenzyme A Dehydrogenases Involved in Bacterial Steroid Degradation

    PubMed Central

    Ruprecht, Amanda; Maddox, Jaymie; Stirling, Alexander J.; Visaggio, Nicole

    2015-01-01

    ABSTRACT The acyl coenzyme A (acyl-CoA) dehydrogenases (ACADs) FadE34 and CasC, encoded by the cholesterol and cholate gene clusters of Mycobacterium tuberculosis and Rhodococcus jostii RHA1, respectively, were successfully purified. Both enzymes differ from previously characterized ACADs in that they contain two fused acyl-CoA dehydrogenase domains in a single polypeptide. Site-specific mutagenesis showed that only the C-terminal ACAD domain contains the catalytic glutamate base required for enzyme activity, while the N-terminal ACAD domain contains an arginine required for ionic interactions with the pyrophosphate of the flavin adenine dinucleotide (FAD) cofactor. Therefore, the two ACAD domains must associate to form a single active site. FadE34 and CasC were not active toward the 3-carbon side chain steroid metabolite 3-oxo-23,24-bisnorchol-4-en-22-oyl-CoA (4BNC-CoA) but were active toward steroid CoA esters containing 5-carbon side chains. CasC has similar specificity constants for cholyl-CoA, deoxycholyl-CoA, and 3β-hydroxy-5-cholen-24-oyl-CoA, while FadE34 has a preference for the last compound, which has a ring structure similar to that of cholesterol metabolites. Knockout of the casC gene in R. jostii RHA1 resulted in a reduced growth on cholate as a sole carbon source and accumulation of a 5-carbon side chain cholate metabolite. FadE34 and CasC represent unique members of ACADs with primary structures and substrate specificities that are distinct from those of previously characterized ACADs. IMPORTANCE We report here the identification and characterization of acyl-CoA dehydrogenases (ACADs) involved in the metabolism of 5-carbon side chains of cholesterol and cholate. The two homologous enzymes FadE34 and CasC, from M. tuberculosis and Rhodococcus jostii RHA1, respectively, contain two ACAD domains per polypeptide, and we show that these two domains interact to form a single active site. FadE34 and CasC are therefore representatives of a new class of

  19. [Effect of fire on understory birds of a gallery forest in central Brazil].

    PubMed

    Marini, M A; Cavalcanti, R B

    1996-11-01

    Habitat burning may cause significant population and community changes in animals and plants, specially when the humans increase fire frequency. We mist-netted the understory birds of a gallery forest from the cerrado region of central Brazil before and after a fire of unknown cause which burned the Ecological Reserve of the University of Brasília, Brasília, DF, in September 1987. We conducted mist-netting mostly during the morning, using 12 mist-nets distributed on 2.5 ha in the interior and border of the forest. We captured 137 individuals of 37 species, 51 individuals of 21 species during 135.5 net/h before the fire, and 98 individuals of 33 species during 233 net/h after the fire. The bird community as a whole did not change after the fire. The observed changes in the bird community were related to the type of habitat used by some species of birds than to their diet. Species typical to gallery forests are probably less adapted to habitat burning than species that occur in other habitats and may be suffering a decrease or a disturbance in their population structure, revealing an important problem of cerrado bird conservation.

  20. Double Variational Binding—(SMILES) Conformational Analysis by Docking Mechanisms for Anti-HIV Pyrimidine Ligands

    PubMed Central

    Putz, Mihai V.; Dudaș, Nicoleta A.; Isvoran, Adriana

    2015-01-01

    Variational quantitative binding–conformational analysis for a series of anti-HIV pyrimidine-based ligands is advanced at the individual molecular level. This was achieved by employing ligand-receptor docking algorithms for each molecule in the 1,3-disubstituted uracil derivative series that was studied. Such computational algorithms were employed for analyzing both genuine molecular cases and their simplified molecular input line entry system (SMILES) transformations, which were created via the controlled breaking of chemical bonds, so as to generate the longest SMILES molecular chain (LoSMoC) and Branching SMILES (BraS) conformations. The study identified the most active anti-HIV molecules, and analyzed their special and relevant bonding fragments (chemical alerts), and the recorded energetic and geometric docking results (i.e., binding and affinity energies, and the surface area and volume of bonding, respectively). Clear computational evidence was also produced concerning the ligand-receptor pocket binding efficacies of the LoSMoc and BraS conformation types, thus confirming their earlier presence (as suggested by variational quantitative structure-activity relationship, variational-QSAR) as active intermediates for the molecule-to-cell transduction process. PMID:26295229

  1. Multiple Infectious Agents and the Origins of Atherosclerotic Coronary Artery Disease

    PubMed Central

    Lawson, James S.

    2016-01-01

    Although deaths due to atherosclerotic coronary artery disease (ACAD) have fallen dramatically during the past 50 years, ACAD remains as the leading cause of death in all continents, except Africa, where deaths due to infections are still dominant. Although food and nutrition have a proven role in atherosclerosis, the underlying causes of ACAD remain unknown. This is despite a century of intensive research dominated by investigations into the saturated fat hypothesis. In this review, it is hypothesized that the rise and fall in ACAD during the past 100 years is primarily due to the parallel rise and fall in the prevalence of coronary atheroma, the underlying disease. It is further hypothesized that infectious pathogens initiate atherosclerosis mainly during infancy and childhood. It is speculated that widespread use of antibiotics and vaccines against bacterial and viral infections may be the reason for the dramatic fall in coronary atheroma and ACAD during the past 50 years. The relevant evidence and a working hypothesis are included in this review.

  2. Multiple Infectious Agents and the Origins of Atherosclerotic Coronary Artery Disease

    PubMed Central

    Lawson, James S.

    2016-01-01

    Although deaths due to atherosclerotic coronary artery disease (ACAD) have fallen dramatically during the past 50 years, ACAD remains as the leading cause of death in all continents, except Africa, where deaths due to infections are still dominant. Although food and nutrition have a proven role in atherosclerosis, the underlying causes of ACAD remain unknown. This is despite a century of intensive research dominated by investigations into the saturated fat hypothesis. In this review, it is hypothesized that the rise and fall in ACAD during the past 100 years is primarily due to the parallel rise and fall in the prevalence of coronary atheroma, the underlying disease. It is further hypothesized that infectious pathogens initiate atherosclerosis mainly during infancy and childhood. It is speculated that widespread use of antibiotics and vaccines against bacterial and viral infections may be the reason for the dramatic fall in coronary atheroma and ACAD during the past 50 years. The relevant evidence and a working hypothesis are included in this review. PMID:27672638

  3. Multiple Infectious Agents and the Origins of Atherosclerotic Coronary Artery Disease.

    PubMed

    Lawson, James S

    2016-01-01

    Although deaths due to atherosclerotic coronary artery disease (ACAD) have fallen dramatically during the past 50 years, ACAD remains as the leading cause of death in all continents, except Africa, where deaths due to infections are still dominant. Although food and nutrition have a proven role in atherosclerosis, the underlying causes of ACAD remain unknown. This is despite a century of intensive research dominated by investigations into the saturated fat hypothesis. In this review, it is hypothesized that the rise and fall in ACAD during the past 100 years is primarily due to the parallel rise and fall in the prevalence of coronary atheroma, the underlying disease. It is further hypothesized that infectious pathogens initiate atherosclerosis mainly during infancy and childhood. It is speculated that widespread use of antibiotics and vaccines against bacterial and viral infections may be the reason for the dramatic fall in coronary atheroma and ACAD during the past 50 years. The relevant evidence and a working hypothesis are included in this review. PMID:27672638

  4. Multiple Infectious Agents and the Origins of Atherosclerotic Coronary Artery Disease.

    PubMed

    Lawson, James S

    2016-01-01

    Although deaths due to atherosclerotic coronary artery disease (ACAD) have fallen dramatically during the past 50 years, ACAD remains as the leading cause of death in all continents, except Africa, where deaths due to infections are still dominant. Although food and nutrition have a proven role in atherosclerosis, the underlying causes of ACAD remain unknown. This is despite a century of intensive research dominated by investigations into the saturated fat hypothesis. In this review, it is hypothesized that the rise and fall in ACAD during the past 100 years is primarily due to the parallel rise and fall in the prevalence of coronary atheroma, the underlying disease. It is further hypothesized that infectious pathogens initiate atherosclerosis mainly during infancy and childhood. It is speculated that widespread use of antibiotics and vaccines against bacterial and viral infections may be the reason for the dramatic fall in coronary atheroma and ACAD during the past 50 years. The relevant evidence and a working hypothesis are included in this review.

  5. An analysis of the daily precipitation variability in the Himalayan orogen using a statistical parameterisation and its potential in driving landscape evolution models with stochastic climatic forcing

    NASA Astrophysics Data System (ADS)

    Deal, Eric; Braun, Jean

    2015-04-01

    A current challenge in landscape evolution modelling is to integrate realistic precipitation patterns and behaviour into longterm fluvial erosion models. The effect of precipitation on fluvial erosion can be subtle as well as nonlinear, implying that changes in climate (e.g. precipitation magnitude or storminess) may have unexpected outcomes in terms of erosion rates. For example Tucker and Bras (2000) show theoretically that changes in the variability of precipitation (storminess) alone can influence erosion rate across a landscape. To complicate the situation further, topography, ultimately driven by tectonic uplift but shaped by erosion, has a major influence on the distribution and style of precipitation. Therefore, in order to untangle the coupling between climate, erosion and tectonics in an actively uplifting orogen where fluvial erosion is dominant it is important to understand how the 'rain dial' used in a landscape evolution model (LEM) corresponds to real precipitation patterns. One issue with the parameterisation of rainfall for use in an LEM is the difference between the timescales for precipitation (≤ 1 year) and landscape evolution (> 103 years). As a result, precipitation patterns must be upscaled before being integrated into a model. The relevant question then becomes: What is the most appropriate measure of precipitation on a millennial timescale? Previous work (Tucker and Bras, 2000; Lague, 2005) has shown that precipitation can be properly upscaled by taking into account its variable nature, along with its average magnitude. This captures the relative size and frequency of extreme events, ensuring a more accurate characterisation of the integrated effects of precipitation on erosion over long periods of time. In light of this work, we present a statistical parameterisation that accurately models the mean and daily variability of ground based (APHRODITE) and remotely sensed (TRMM) precipitation data in the Himalayan orogen with only a few

  6. [ASSOCIATION BETWEEN FITNESS, NUTRITIONAL STATUS AND ACADEMIC PERFORMANCE IN PHYSICAL EDUCATION STUDENTS].

    PubMed

    Godoy Cumillaf, Andrés; Valdés Badilla, Pablo; Fariña Herrera, Custodio; Cárcamo Mora, Francisco; Medina Herrera, Bernice; Meneses Sandoval, Elías; Gedda Muñoz, Relmu; Durán Agüero, Samuel

    2015-10-01

    Introducción: diversas investigaciones han señalado que la práctica regular de ejercicio físico impactaría positivamente sobre el rendimiento académico de los estudiantes. Objetivo: determinar la asociación entre la condición física, el estado nutricional y el rendimiento académico de estudiantes de Pedagogía en Educación Física de Temuco, Chile. Material y métodos: la muestra fue seleccionada bajo un criterio no probabilístico, que incluyó 208 sujetos (n = 153 hombres y n = 55 mujeres). Las variables estudiadas correspondieron a la condición física (abdominales cortos, salto largo a pies juntos, flexión de tronco adelante, flexo-extensión de codos y test course navette), estado nutricional (índice de masa corporal –,IMC) y rendimiento académico (sobre el promedio y bajo el promedio). Resultados: un 87,5% de los estudiantes presentan una condición física satisfactoria y un IMC promedio de 23,8 ± 2,9 kg/m2, siendo aquellos que alcanzan mejores valores de rendimiento académico los que poseen también mayor proporción de condición física satisfactoria (92,5%). Al realizar la asociación entre las variables estudiadas, no hubo asociación entre rendimiento académico y estado nutricional, pero sí entre baja condición física y un mayor riesgo de presentar un menor rendimiento académico (OR = 2,8; IC95%:1,0-8,1; p < 0,05). Conclusión: se observa una asociación entre rendimiento académico y condición física entre los estudiantes, pero no se asocia el estado nutricional con el rendimiento académico.

  7. High contrast imaging with an arbitrary aperture: active correction of aperture discontinuities: fundamental limits and practical trades offs

    NASA Astrophysics Data System (ADS)

    Pueyo, Laurent; Norman, Colin Arthur; Soummer, Remi; Perrin, Marshall D.; N'Diaye, Mamadou; Choquet, Elodie

    2015-01-01

    In a recent paper we discussed a new method to achieve high-contrast images using segmented and/or on-axis telescopes. Our approach, named Active Compensation of Aperture Discontinuities (ACAD) relies on two sequential Deformable Mirrors to compensate for the large amplitude excursions in the telescope aperture due to secondary support structures and/or segment gaps. In this configuration the parameter landscape of Deformable Mirror Surfaces that yield high contrast Point Spread Functions is not linear, and non-linear methods are needed to find the true minimum. In particular we showed that broadband high contrast solutions can be achieved using realistic surface deformations that are accessible using existing technologies for a variety of telescope pupil geometries. In this paper we first focus on the fundamental limits and practical trade-offs associated with ACAD. In a first part we will study the fundamental limits and practical tradeoffs associated with ACAD, regardless of the downstream coronagraphic architecture. The mathematical techniques to finding ACAD DM shapes require to solve a complex differential equation. We will first discuss the scaling laws underlying this non-linear solution and their impact of DM placement and geometry wishing the optical design of an instrument. We will then consider the sensitivity to low order aberrations: in principle an ACAD solution that comprises large strokes will be more sensitive to these aberrations than one with smaller strokes. As a consequence, we will quantify this sensitive both using analytical models and numerical simulations. We will present diffractive end to end simulations and quantify the ultimate contrast and bandwidth achievable with ACAD, which can be reached by superposing using a classical linear wavefront control algorithms on top of the Monge Ampere solution. Finally, recent work has shown that coronagraph designs can also accommodate for secondary support structures and/or segments gaps, at a

  8. Entry into labour: The experience of young adults in Brazil

    NASA Astrophysics Data System (ADS)

    Gomes, Candido A.

    1990-12-01

    This study focuses on the experience of young adults employed in the tertiary sector in Brasília. The results show that young people are prepared for work by on-the-job training and nonformal education; schooling is mainly an indicator of trainability. Entry into the labour force reinforces social differences in family background and schooling. The results tend to support the moderate version of classical theory with regard to the nature of school/work relationships. In the context of the conflict paradigm, the data run contrary to both reproductionism and the radical critique of this view. From the comparative standpoint youth is an underprivileged group in the labour market, regardless of sex, socioeconomic status and country of residence. Despite these variations, societies are stratified by age groups.

  9. Paleomagnetic Progress in Peri-Gondwanan Terranes of Cape Breton Island, Nova Scotia

    NASA Astrophysics Data System (ADS)

    Grunow, A. M.; Thompson, M. D.; Barr, S. M.; White, C. E.

    2009-05-01

    Paleopoles from primary Ediacaran magnetization directions established the Gondwanan origin of northern Appalachian Avalonian terranes, but magnetic overprints in the same rocks also provide useful tectonic information. Thus, in the Southeastern New England Avalon Zone, virtual geomagnetic poles (VGPs) calculated from magnetic B and C components in both 595 Ma Lynn-Mattapan volcanic rocks and 490-488 Ma Nahant Gabbro track mid- and late Paleozoic segments of the North American apparent polar wander path (APWP), suggesting the influence of Acadian and Neo-Acadian accretionary events. We report here on multi- vectorial magnetizations in pilot samples from Cape Breton Island, Nova Scotia where the Bras d'Or and Mira terranes represent both Ganderian and Avalonian elements transferred from Gondwana. Overprint relationships in these terranes may constrain their amalgamation with each other as well their docking with Laurentia. As in southeastern New England, secondary remanences can be identified in Cape Breton Island as consistent magnetization directions in rocks of differing ages. The S- to SSE-trending and gently downward pointing direction reported in 1985 by Johnson and Van der Voo in Middle Cambrian sedimentary rocks of the Bourinot Group (Bras d'Or terrane), for example, is also present in the 563 Ma Main à Dieu Formation and in 620 Ma Chisholm Brook Granite and East Bay Hill rhyolite (Mira terrane). This magnetization represents the C component already found around Boston, MA. The resulting VGPs in both areas occupy positions on the North American APWP consistent with a Neo-Acadian overprint, possibly related to the docking of the Meguma terrane against previously accreted Avalonia. Other overprint directions encountered in this investigation give rise to VGPs that do not coincide with the North American APWP, hence appear to reflect tectonic events independent of Laurentia. One such cluster comprising both Mira and Bras d'Or VGPs includes the paleopole also

  10. Pickless event detection and location: The waveform correlation event detection system (WCEDS) revisited

    DOE PAGES

    Arrowsmith, Stephen John; Young, Christopher J.; Ballard, Sanford; Slinkard, Megan Elizabeth

    2016-01-01

    The standard paradigm for seismic event monitoring breaks the event detection problem down into a series of processing stages that can be categorized at the highest level into station-level processing and network-level processing algorithms (e.g., Le Bras and Wuster (2002)). At the station-level, waveforms are typically processed to detect signals and identify phases, which may subsequently be updated based on network processing. At the network-level, phase picks are associated to form events, which are subsequently located. Furthermore, waveforms are typically directly exploited only at the station-level, while network-level operations rely on earth models to associate and locate the events thatmore » generated the phase picks.« less

  11. Pickless event detection and location: The waveform correlation event detection system (WCEDS) revisited

    SciTech Connect

    Arrowsmith, Stephen John; Young, Christopher J.; Ballard, Sanford; Slinkard, Megan Elizabeth

    2016-01-01

    The standard paradigm for seismic event monitoring breaks the event detection problem down into a series of processing stages that can be categorized at the highest level into station-level processing and network-level processing algorithms (e.g., Le Bras and Wuster (2002)). At the station-level, waveforms are typically processed to detect signals and identify phases, which may subsequently be updated based on network processing. At the network-level, phase picks are associated to form events, which are subsequently located. Furthermore, waveforms are typically directly exploited only at the station-level, while network-level operations rely on earth models to associate and locate the events that generated the phase picks.

  12. Fruit consumption and seed dispersal of Dimorphandra mollis Benth. (Leguminosae) by the lowland tapir in the cerrado of Central Brazil.

    PubMed

    Bizerril, M X A; Rodrigues, F H G; Hass, A

    2005-08-01

    Fruit phenology observations and consumption of Dimorphandra mollis (Leguminosae) were analyzed during seven months in an area of cerrado stricto sensu. We analysed 81 fecal samples collected at six different places of lowland tapirs (Tapirus terrestris) in central Brazilian cerrado. In addition, from the feces of five tapirs at the Brasília Zoo to which fruit had been offered, seeds were collected and used in germination tests. The results suggest that the tapir is an important fruit consumer and a potential seed disperser of D. mollis. In the field, however, fruit consumption was found to be very low, probably because of both fruit palatability and the low density of frugivores, especially tapirs. The possibility that the original dispersal agents of D. mollis seeds belonged to the South American Pleistocene megafauna is discussed.

  13. Relationship and responsiveness of three upper-limb tests in patients with chronic obstructive pulmonary disease.

    PubMed

    Janaudis-Ferreira, Tania; Hill, Kylie; Goldstein, Roger S; Wadell, Karin; Brooks, Dina

    2013-01-01

    Objectif : Cette étude visait à déterminer (1) la relation entre trois tests courants des membres supérieurs et la maladie pulmonaire obstructive chronique (MPOC) : test UULEX (test d'élévation d'un membre supérieur), test de l'anneau (6PBRT) et évaluation de la force musculaire à l'aide d'un dynamomètre manuel; et (2) le degré de réactivité au changement de ces trois tests après une réadaptation pulmonaire comprenant un programme d'entraînement en résistance des bras. Méthode : Cette étude était une analyse secondaire d'un essai clinique randomisé (ECR). Le test UULEX et le 6PBRT ont été utilisés pour mesurer la capacité maximale d'exercice et la fonction maximale du bras, respectivement. Un dynamomètre manuel a été utilisé pour mesurer la force de flexion du coude et de l'épaule. Nous avons analysé les données de base de tous les patients qui ont participé à l'ECR de même que les données de base et les données après réadaptation pulmonaire des patients qui ont participé à 6 semaines de tests de suivi. Résultats : 36 patients avec MPOC (moyenne de volume expiratoire maximal [SD] par seconde [VEMS1]=35 % [15 %] prévus; 66 ans [9]) y ont participé et de ce nombre, 13 ont participé au programme d'entraînement des bras. Les corrélations entre les résultats des tests se chiffraient de 0,41 à 0,81 (p<0.0001). Les moyennes de réponse normalisées ont été de 1,0 pour la force musculaire de flexion du coude, de 1,2 pour la flexion de l'épaule et de 1,8 pour les tests 6PBRT et UULEX. Conclusions : Bien que ces trois tests (UULEX, 6PBRT et test de force musculaire à l'aide du dynamomètre manuel) visent à mesurer des dimensions différentes, ces mesures étaient modérément ou extrêmement corrélées les unes par rapport aux autres. Le test 6PBRT, le test UULEX et le test de force musculaire ont manifestement été influencés par le programme d'entraînement en résistance des bras.

  14. Color vision in the black howler monkey (Alouatta caraya).

    PubMed

    Araújo, Antônio C; Didonet, Julia J; Araújo, Carolina S; Saletti, Patrícia G; Borges, Tânia R J; Pessoa, Valdir F

    2008-01-01

    Electrophysiological and molecular genetic studies have shown that howler monkeys (Alouatta) are unique among all studied platyrrhines: they have the potential to display trichromatic color vision among males and females. This study examined the color discrimination abilities of four howler monkeys (Alouatta caraya) through a series of tasks involving a behavioral paradigm of discrimination learning. The animals were maintained and housed as a group in the Zoological Gardens of Brasília and were tested in their own home cages. Stimuli consisting of pairs of Munsell color chips were presented in random brightness values to assure that discriminations were based on color rather than brightness cues. All the animals (three males, one female) successfully discriminated all the stimulus pairs, including those that would be expected to be difficult for a dichromatic monkey. These results are consistent with the earlier predictions suggesting that howler monkeys are routinely trichromatic. PMID:18598395

  15. [Training process of the social representations on transsexuality among health professionals: possible ways to overcome prejudice].

    PubMed

    Santos, Adelyany Batista dos; Shimizu, Helena Eri; Merchan-Hamann, Edgar

    2014-11-01

    The scope of this paper is to identify and analyze the structure of social representations of health professionals about transsexuality. The theoretical and methodological benchmark used was the structural approach to social representations developed by Jean-Claude Abric. 128 health professionals from 22 health units in the State Health Department of the Federal District of Brasília were interviewed. Data collection consisted of the application of a semi-structured questionnaire based on the technique of free association with the key word "transsexuality." The data were processed using EVOC 2000 software. The profile of the subjects reveals the predominance of female participants and professionals in the field of nursing. The terms "sex change" and "prejudice" seem to feature as the central nucleus, and "transformation," "option," "respect" and "acceptance" are the peripheral systems of representation.

  16. [REBEn in the context of the history of Brazilian nursing: the significance of remembering Dr. Glete de Alcântara].

    PubMed

    Mendes, Isabel Amélia Costa; Leite, Joséte Luzia; Leite, Juçara Luzia; Trevizan, Maria Auxiliadora

    2002-01-01

    This is a Social History study which aims at recuperating the professional trajectory of Glete de Alcântara in the Revista Brasileira de Enfermagem/REBEn (Brazilian Journal of Nursing), initially called Anais de Enfermagem. It is based on the concept of memory of Maurice Halbwach, and on the concept of generation of Daniel Pécaut. The study contextualizes the professional development of Glete de Alcântara in the history of the Brazilian nursing, highlighting the creation of the Nursing School of the University of São Paulo (EERP/USP) in Ribeirão Preto. The sources for the study were documents obtained in the Centro de Memória da Escola de Enfermagem (Memory Center of the School of Nursing) of Ribeirão Preto and in ABEN (Brazilian Association of Nursing) in Brasília. Data obtained in this association were mainly collected from its record books the journals.

  17. Role of vegetation in modulating denudation and topography across the Himalaya

    NASA Astrophysics Data System (ADS)

    Olen, Stephanie; Bookhagen, Bodo; Strecker, Manfred

    2015-04-01

    Studies of Himalayan denudation, to date, have primarily focused on the effects of lithology, tectonic activity, and climate in shaping landscape and controlling denudation rates. Climate can impact denudation not only through increased precipitation, runoff, or glaciation, but also via its role in controlling vegetation cover. Since the classical study of Langbein and Schumm [1958] emphasizing the role of vegetation cover in determining erosional efficiency, theoretical and plot-scale studies have highlighted the role of vegetation on surface processes [Collins et al., 2004; Istanbulluoglu and Bras, 2005; Collins and Bras, 2010; Carretier et al., 2013; Jeffery et al., 2014]. Vegetation cover and density vary considerably in the Himalaya, both across and along strike. Across strike, vegetation transitions from dense forest and agriculturally-used plots in the Lesser Himalaya to sparse alpine and arid, virtually non-vegetated regions at high elevation and in the rain shadow north of the Higher Himalaya peaks. Along-strike vegetation densities also differ significantly and show a pronounced E-W gradient. To quantify the along-strike vegetation gradient, we use 14 years of MODIS 13C1 enhanced vegetation index (EVI) data to calculate mean annual, summer (MJJASO), and winter (NDJFMA) for the entire Himalaya. Additionally, we calculate a differential EVI that compares summer versus winter vegetation density (MJJASO/NDJFMA). A decrease in vegetation density is observed from east to west, with the greatest difference in winter vegetation cover (225% higher in the eastern than western Himalaya). In contrast, differential EVI is higher in the western Himalaya, increasing 170% from east to west. To evaluate the effect of vegetation on denudation and landscape evolution, we combine the 14-year EVI data, topographic analysis, and a compilation of >100 published and unpublished 10-Be terrestrial cosmogenic nuclide (TCN) catchment-mean denudation rates from across the Himalaya

  18. Stiff-person syndrome treated with rituximab

    PubMed Central

    Lobo, Marcelo Evangelista; Araújo, Marx Lincoln Barros; Tomaz, Carlos Alberto Bezerra; Allam, Nasser

    2010-01-01

    Stiff-person syndrome (SPS) is a rare neurological condition consisting of progressive and fluctuating rigidity of the axial muscles combined with painful spasms. The pathophysiology of SPS is not fully understood, but there seems to be an autoimmune component. The use of rituximab, a chimeric monoclonal antibody targeting CD20 protein in the surface of mature B cells, for the treatment of SPS is a recent therapeutical approach showing promising results. The authors present a case report of a 41-year-old female patient diagnosed with SPS who was treated with rituximab in a public hospital in Brasília, Brazil, showing a good and safe response to the treatment so far. Our data go along with some recent articles published in the literature. PMID:22802263

  19. Toxicity and genotoxicity of wastewater from gasoline stations.

    PubMed

    Oliveira-Martins, Cynthia R; Grisolia, Cesar K

    2009-10-01

    The toxicity and genotoxicity of wastewater from eight gasoline stations in Brasília, Brazil's capital city, was studied by assessing chromosomal aberrations, chromosomal malsegregation and the mitotic index in Alliumcepa root cells, and the occurrence of micronucleus and nuclear abnormalities in peripheral erythrocytes of tilapia fish (Oreochromis niloticus). The content of gasoline station effluents was also analyzed based on several physico-chemical parameters. None of the wastewater samples was genotoxic to A. cepa root cells, although cell proliferation was significantly inhibited, especially at the highest concentrations. Likewise, no micronuclei were observed in O. niloticus peripheral erythrocytes, even after exposure to high concentrations, but there was an increase in the number of nuclear abnormalities and fish mortality. These results show that although the effluent from gasoline stations is processed by an oil/water separation system before being discharged into the main sewage system, the wastewater still contains toxic compounds.

  20. Toxicity and genotoxicity of wastewater from gasoline stations

    PubMed Central

    2009-01-01

    The toxicity and genotoxicity of wastewater from eight gasoline stations in Brasília, Brazil's capital city, was studied by assessing chromosomal aberrations, chromosomal malsegregation and the mitotic index in Alliumcepa root cells, and the occurrence of micronucleus and nuclear abnormalities in peripheral erythrocytes of tilapia fish (Oreochromis niloticus). The content of gasoline station effluents was also analyzed based on several physico-chemical parameters. None of the wastewater samples was genotoxic to A. cepa root cells, although cell proliferation was significantly inhibited, especially at the highest concentrations. Likewise, no micronuclei were observed in O. niloticus peripheral erythrocytes, even after exposure to high concentrations, but there was an increase in the number of nuclear abnormalities and fish mortality. These results show that although the effluent from gasoline stations is processed by an oil/water separation system before being discharged into the main sewage system, the wastewater still contains toxic compounds. PMID:21637464

  1. Assessing the HIV-1 Epidemic in Brazilian Drug Users: A Molecular Epidemiology Approach

    PubMed Central

    Guimarães, Monick Lindenmeyer; Marques, Bianca Cristina Leires; Bertoni, Neilane; Teixeira, Sylvia Lopes Maia; Morgado, Mariza Gonçalves; Bastos, Francisco Inácio

    2015-01-01

    Person who inject illicit substances have an important role in HIV-1 blood and sexual transmission and together with person who uses heavy non-injecting drugs may have less than optimal adherence to anti-retroviral treatment and eventually could transmit resistant HIV variants. Unfortunately, molecular biology data on such key population remain fragmentary in most low and middle-income countries. The aim of the present study was to assess HIV infection rates, evaluate HIV-1 genetic diversity, drug resistance, and to identify HIV transmission clusters in heavy drug users (DUs). For this purpose, DUs were recruited in the context of a Respondent-Driven Sampling (RDS) study in different Brazilian cities during 2009. Overall, 2,812 individuals were tested for HIV, and 168 (6%) of them were positive, of which 19 (11.3%) were classified as recent seroconverters, corresponding to an estimated incidence rate of 1.58%/year (95% CI 0.92–2.43%). Neighbor joining phylogenetic trees from env and pol regions and bootscan analyses were employed to subtype the virus from132 HIV-1-infected individuals. HIV-1 subtype B was prevalent in most of the cities under analysis, followed by BF recombinants (9%-35%). HIV-1 subtype C was the most prevalent in Curitiba (46%) and Itajaí (86%) and was also detected in Brasília (9%) and Campo Grande (20%). Pure HIV-1F infections were detected in Rio de Janeiro (9%), Recife (6%), Salvador (6%) and Brasília (9%). Clusters of HIV transmission were assessed by Maximum likelihood analyses and were cross-compared with the RDS network structure. Drug resistance mutations were verified in 12.2% of DUs. Our findings reinforce the importance of the permanent HIV-1 surveillance in distinct Brazilian cities due to viral resistance and increasing subtype heterogeneity all over Brazil, with relevant implications in terms of treatment monitoring, prophylaxis and vaccine development. PMID:26536040

  2. Exhumation history of the Serra do Mar, southeast Brazil

    NASA Astrophysics Data System (ADS)

    Carina Siqueira-Ribeiro, Marli; Hackspacher, Peter; Stuart, Finlay M.

    2016-04-01

    The Serra do Mar (SM) mountain range located along the southeast Brazilian continental margin is characterized by a low-lying coastal plateau separated from the elevated inland plateau by a steep escarpment. This morphology is a result of reactivation of Precambrian shear zones since the break-up of the Western Gondwana and opening of the South Atlantic Ocean in Early Cretaceous (1). Previous Thermochronological data from southeast Brazilian highlands (2,3), indicates that the landscape evolution is associated with several distinct exhumation events. In order to clarify the intensity and duration of the post-break up tectonic processes that shaped the SM we have undertaken a low temperature thermochronology study of crystalline basement, from the plateaus and escarpments situated between south of Rio de Janeiro and São Paulo state. Apatite fission track (AFT) and (U-Th/He) and (AHe) dating has been combined with geologic information to generate precise thermal histories and make initial attempts to quantify the amount of exhumation. AFT ages range from 145 to 53 Ma whereas preliminary AHe ages range from 75 to 37 Ma. Forward modeling using QTQt confirms Late Cretaceous-Paleogene cooling identified earlier (4,5) and identifies a distinct cooling phase in Neogene, between 30 and 10 Ma. Neogene cooling rapid caused exhumation of rocks 1 km through of the crust mainly in south portion of the SM in Rio de Janeiro state. (1) Almeida, 1976. An. Academia Bras de Cien 48 (suppl.), 15-(2) (2) Hackspacher et al. 2004. Gondwana Research,vol.2, 91-101. (3) Hiruma et al. 2010. Gondwana Research,18,674-687. (4) Siqueira-Ribeiro et al. 2011. Revista Bras. de Geomorfologia, 13, 3-14 (5) Cogné et al. 2012. Journal Geophysical Research, vol.117,1-16.

  3. Field measurement of soil moisture dynamics and numerical simulation using the kinematic wave approximation

    NASA Astrophysics Data System (ADS)

    Rezzoug, A.; Schumann, A.; Chifflard, P.; Zepp, H.

    2005-09-01

    We investigate in this paper the effect of plane and profile curvatures on the soil moisture distribution and related fluxes obtained from field experiments. Today, there is a need also to confirm the theoretical approaches of the kinematic wave approximation with the real field measurements. Within a research project dedicated to the model-based description of runoff formation processes, field measurements of soil moisture dynamics and numerical simulation, using one simply formulated kinematic wave model, are combined. It is shown that the measurement of the soil moisture movement downwards within a hillslope can be interpreted by the kinematic wave model and vice versa how the model can be validated in its physical explanations by the field measurements. It is revealed that the soil moisture fluxes can be described by kinematic waves crossing the soil mantle of the hillslope. Based on these analyses it is shown that the two topographic characteristics plane and profile curvatures of the hillslope control the subsurface and saturation flow. The obtained results are related to the previous theoretical analysis of Fan and Bras [Fan Y, Bras RL. Analytical solutions to hillslope subsurface storm flow and saturation overland flow. Water Resour Res 1998;34(4):921-7], Troch et al. [Troch PA, Paniconi C, van Loon EE, Bijkerk B, Hilberts A. Behaviour of a hillslope-storage Boussinesq model for subsurface storm flow and saturation overland flow. International Workshop on Catchment, Wageningen 2000; Poster] and Troch et al. [Troch PA, van Loon C, Hilberts A. Analytical solutions to a hillslope-storage kinematic wave equation for subsurface flow. Adv Water Resour 2002;25:637-49] which have shown considerable progress in the modelling using the kinematic wave approximation.

  4. Safety performance models for urban intersections in Brazil.

    PubMed

    Barbosa, Heloisa; Cunto, Flávio; Bezerra, Bárbara; Nodari, Christine; Jacques, Maria Alice

    2014-09-01

    This paper presents a modeling effort for developing safety performance models (SPM) for urban intersections for three major Brazilian cities. The proposed methodology for calibrating SPM has been divided into the following steps: defining the safety study objective, choosing predictive variables and sample size, data acquisition, defining model expression and model parameters and model evaluation. Among the predictive variables explored in the calibration phase were exposure variables (AADT), number of lanes, number of approaches and central median status. SPMs were obtained for three cities: Fortaleza, Belo Horizonte and Brasília. The SPM developed for signalized intersections in Fortaleza and Belo Horizonte had the same structure and the most significant independent variables, which were AADT entering the intersection and number of lanes, and in addition, the coefficient of the best models were in the same range of values. For Brasília, because of the sample size, the signalized and unsignalized intersections were grouped, and the AADT was split in minor and major approaches, which were the most significant variables. This paper also evaluated SPM transferability to other jurisdiction. The SPM for signalized intersections from Fortaleza and Belo Horizonte have been recalibrated (in terms of the Cx) to the city of Porto Alegre. The models were adjusted following the Highway Safety Manual (HSM) calibration procedure and yielded Cx of 0.65 and 2.06 for Fortaleza and Belo Horizonte SPM respectively. This paper showed the experience and future challenges toward the initiatives on development of SPMs in Brazil, that can serve as a guide for other countries that are in the same stage in this subject.

  5. Shrinking the FadE proteome of Mycobacterium tuberculosis: insights into cholesterol metabolism through identification of an α2β2 heterotetrameric acyl coenzyme A dehydrogenase family.

    PubMed

    Wipperman, Matthew F; Yang, Meng; Thomas, Suzanne T; Sampson, Nicole S

    2013-10-01

    The ability of the pathogen Mycobacterium tuberculosis to metabolize steroids like cholesterol and the roles that these compounds play in the virulence and pathogenesis of this organism are increasingly evident. Here, we demonstrate through experiments and bioinformatic analysis the existence of an architecturally distinct subfamily of acyl coenzyme A (acyl-CoA) dehydrogenase (ACAD) enzymes that are α2β2 heterotetramers with two active sites. These enzymes are encoded by two adjacent ACAD (fadE) genes that are regulated by cholesterol. FadE26-FadE27 catalyzes the dehydrogenation of 3β-hydroxy-chol-5-en-24-oyl-CoA, an analog of the 5-carbon side chain cholesterol degradation intermediate. Genes encoding the α2β2 heterotetrameric ACAD structures are present in multiple regions of the M. tuberculosis genome, and subsets of these genes are regulated by four different transcriptional repressors or activators: KstR1 (also known as KstR), KstR2, Mce3R, and SigE. Homologous ACAD gene pairs are found in other Actinobacteria, as well as Proteobacteria. Their structures and genomic locations suggest that the α2β2 heterotetrameric structural motif has evolved to enable catalysis of dehydrogenation of steroid- or polycyclic-CoA substrates and that they function in four subpathways of cholesterol metabolism.

  6. Optical information processing based on an associative-memory model of neural nets with thresholding and feedback.

    PubMed

    Psaltis, D; Farhat, N

    1985-02-01

    The remarkable collective computational properties of the Hopfield model for neural networks [Proc. Nat. Acad. Sci. USA 79, 2554 (1982)] are reviewed. These include recognition from partial input, robustness, and error-correction capability. Features of the model that make its optical implementation attractive are discussed, and specific optical implementation schemes are given.

  7. The Threat of the Dyscompetent Resident: A Plea to Make the Implicit More Explicit!

    ERIC Educational Resources Information Center

    van Mook, Walther N. K. A.; van Luijk, Scheltus J.; Zwietering, P. J.; Southgate, L.; Schuwirth, Lambert W. T.; Scherpbier, Albert J. J. A.; van der Vleuten, Cees P. M.

    2015-01-01

    Although several examples of frameworks dealing with "students'" unprofessional behaviour are available, guidance on how to deal locally or regionally with dysfunctional "residents" is limited (Hickson et al. in "Acad Med" 82(11):1040-1048, 2007b; Leape and Fromson in "Ann Intern Med" 144(2):107-115, 2006).…

  8. OCCURRENCE AND ORIENTATION OF PARALICHTHID FLOUNDERS (BOTHIDAE: PARALICHTYS) ON AN INTERTIDAL BEACH

    EPA Science Inventory

    Middaugh, Douglas P. and Charles L. McKenney, Jr. 2003. Occurrence and Orientation of Flounders (Bothidae: Paralichthys) on an Intertidal Beach. J. North Carol. Acad. Sci. 119(4):157-171. (ERL,GB 1172).

    The intertidal movement and burying pattern of paralichthid flounders...

  9. 75 FR 34891 - Carol M. White Physical Education Program; Catalog of Federal Domestic Assistance (CFDA) Number...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ... Henderson K. Does obesity prevention cause eating disorders? J Am Acad Child Adolesc Psychiatry, 2009, 48(8... research related to improving children's health and fitness, to improve students' physical activity, and to...) in the Federal Register on March 16, 2010 (75 FR 12522). That notice contained background...

  10. New Organisational Structures and the Transformation of Academic Work

    ERIC Educational Resources Information Center

    Nyhagen, Gigliola Mathisen; Baschung, Lukas

    2013-01-01

    This article will particularly focus on Norway and the consequences for academic work. Frequently in studies of academic work, focus has been on academics' individual autonomy and to what extent the latter is challenged (Altbach in "Ann Am Acad Pol Soc Sci" 448:1-14, 1980; Shattock in "High Educ" 41:27-47, 2001). One of…

  11. Spike-forming model of the neural membrane: Improvement in the parameter values

    PubMed Central

    Wooldridge, Dean E.

    1976-01-01

    A new set of values is presented for the reaction rate and ionic conductance parameters that determine the properties of the previously developed model of the neural membrane [Wooldridge, D.E. (1975) Proc. Natl. Acad. Sci. USA 72, 3468-3471]. The resulting improvement in the extent of the agreement between theory and experiment is briefly described. PMID:1065874

  12. A visual LISP program for voxelizing AutoCAD solid models

    NASA Astrophysics Data System (ADS)

    Marschallinger, Robert; Jandrisevits, Carmen; Zobl, Fritz

    2015-01-01

    AutoCAD solid models are increasingly recognized in geological and geotechnical 3D modeling. In order to bridge the currently existing gap between AutoCAD solid models and the grid modeling realm, a Visual LISP program is presented that converts AutoCAD solid models into voxel arrays. Acad2Vox voxelizer works on a 3D-model that is made up of arbitrary non-overlapping 3D-solids. After definition of the target voxel array geometry, 3D-solids are scanned at grid positions and properties are streamed to an ASCII output file. Acad2Vox has a novel voxelization strategy that combines a hierarchical reduction of sampling dimensionality with an innovative use of AutoCAD-specific methods for a fast and memory-saving operation. Acad2Vox provides georeferenced, voxelized analogs of 3D design data that can act as regions-of-interest in later geostatistical modeling and simulation. The Supplement includes sample geological solid models with instructions for practical work with Acad2Vox.

  13. Shrinking the FadE Proteome of Mycobacterium tuberculosis: Insights into Cholesterol Metabolism through Identification of an α2β2 Heterotetrameric Acyl Coenzyme A Dehydrogenase Family

    PubMed Central

    Wipperman, Matthew F.; Yang, Meng; Thomas, Suzanne T.

    2013-01-01

    The ability of the pathogen Mycobacterium tuberculosis to metabolize steroids like cholesterol and the roles that these compounds play in the virulence and pathogenesis of this organism are increasingly evident. Here, we demonstrate through experiments and bioinformatic analysis the existence of an architecturally distinct subfamily of acyl coenzyme A (acyl-CoA) dehydrogenase (ACAD) enzymes that are α2β2 heterotetramers with two active sites. These enzymes are encoded by two adjacent ACAD (fadE) genes that are regulated by cholesterol. FadE26-FadE27 catalyzes the dehydrogenation of 3β-hydroxy-chol-5-en-24-oyl-CoA, an analog of the 5-carbon side chain cholesterol degradation intermediate. Genes encoding the α2β2 heterotetrameric ACAD structures are present in multiple regions of the M. tuberculosis genome, and subsets of these genes are regulated by four different transcriptional repressors or activators: KstR1 (also known as KstR), KstR2, Mce3R, and SigE. Homologous ACAD gene pairs are found in other Actinobacteria, as well as Proteobacteria. Their structures and genomic locations suggest that the α2β2 heterotetrameric structural motif has evolved to enable catalysis of dehydrogenation of steroid- or polycyclic-CoA substrates and that they function in four subpathways of cholesterol metabolism. PMID:23836861

  14. Genetics Home Reference: hidradenitis suppurativa

    MedlinePlus

    ... Apr;60(4):539-61; quiz 562-3. doi: 10.1016/j.jaad.2008.11.911. Review. ... Acad Dermatol. 2009 Jul;61(1):51-7. doi: 10.1016/j.jaad.2009.02.013. Epub ... Dermatol Clin. 2010 Oct;28(4):779-93. doi: 10.1016/j.det.2010.07.003. Review. ...

  15. Langevin Theory of Anomalous Brownian Motion Made Simple

    ERIC Educational Resources Information Center

    Tothova, Jana; Vasziova, Gabriela; Glod, Lukas; Lisy, Vladimir

    2011-01-01

    During the century from the publication of the work by Einstein (1905 "Ann. Phys." 17 549) Brownian motion has become an important paradigm in many fields of modern science. An essential impulse for the development of Brownian motion theory was given by the work of Langevin (1908 "C. R. Acad. Sci.", Paris 146 530), in which he proposed an…

  16. Genetics Home Reference: pseudohypoaldosteronism type 1

    MedlinePlus

    ... hyperkalaemic acidosis, pseudohypoaldosteronism type 1. Nat Genet. 1996 Mar;12(3):248-53. Citation on PubMed Chen ... sgk. Proc Natl Acad Sci U S A. 1999 Mar 2;96(5):2514-9. Citation on PubMed ...

  17. The gravitational problem of a single body within invariantive mechanics

    NASA Astrophysics Data System (ADS)

    Ionescu-Pallas, Nicolae I.; Sofonea, Liviu

    The authors discusse problems of main gravitational tests in the framework of the theory of Invariantive mechanics, formulated by Octav Onicescu (Springer Verlag, Berlin, 1978; Rendiconti d. Acad. naz. dei Lincei, vol.XXXYI, fasc. d, Avril 1984 (in coauthorship with Ionel Bucur)).

  18. Proteomics and gene expression analyses of mitochondria from squalene-treated apoE-deficient mice identify short-chain specific acyl-CoA dehydrogenase changes associated with fatty liver amelioration.

    PubMed

    Ramírez-Torres, Adela; Barceló-Batllori, Sílvia; Fernández-Vizarra, Erika; Navarro, María A; Arnal, Carmen; Guillén, Natalia; Acín, Sergio; Osada, Jesús

    2012-05-17

    Squalene, a hydrocarbon involved in cholesterol biosynthesis, is an abundant component in virgin olive oil. Previous studies showed that its administration decreased atherosclerosis and steatosis in male apoE knock-out mice. To study the effect of squalene on mitochondrial proteins in fatty liver, 1 g/kg/day of this isoprenoid was administered to those mice. After 10 weeks, hepatic fat was assessed and protein extracts from mitochondria enriched fractions from control and squalene-treated animals were analyzed by 2D-DIGE. Spots exhibiting significant differences were identified by MS analysis. Squalene administration modified the expression of eighteen proteins involved in different metabolic processes, 12 associated with hepatic fat content. Methionine adenosyltransferase I alpha (Mat1a) and short-chain specific acyl-CoA dehydrogenase (Acads) showed significant increased and decreased transcripts, respectively, consistent with their protein changes. These mRNAs were also studied in wild-type mice receiving squalene, where Mat1a was found increased and Acads decreased. However, this mRNA was significantly increased in the absence of apolipoprotein E. These results suggest that squalene action may be executed through a complex regulation of mitochondrial protein expression, including changes in Mat1a and Acads levels. Indeed, Mat1a is a target of squalene administration while Acads reflects the anti-steatotic properties of squalene.

  19. Role of vegetation in modulating denudation and topography across the Himalaya

    NASA Astrophysics Data System (ADS)

    Olen, Stephanie; Bookhagen, Bodo; Strecker, Manfred

    2015-04-01

    Studies of Himalayan denudation, to date, have primarily focused on the effects of lithology, tectonic activity, and climate in shaping landscape and controlling denudation rates. Climate can impact denudation not only through increased precipitation, runoff, or glaciation, but also via its role in controlling vegetation cover. Since the classical study of Langbein and Schumm [1958] emphasizing the role of vegetation cover in determining erosional efficiency, theoretical and plot-scale studies have highlighted the role of vegetation on surface processes [Collins et al., 2004; Istanbulluoglu and Bras, 2005; Collins and Bras, 2010; Carretier et al., 2013; Jeffery et al., 2014]. Vegetation cover and density vary considerably in the Himalaya, both across and along strike. Across strike, vegetation transitions from dense forest and agriculturally-used plots in the Lesser Himalaya to sparse alpine and arid, virtually non-vegetated regions at high elevation and in the rain shadow north of the Higher Himalaya peaks. Along-strike vegetation densities also differ significantly and show a pronounced E-W gradient. To quantify the along-strike vegetation gradient, we use 14 years of MODIS 13C1 enhanced vegetation index (EVI) data to calculate mean annual, summer (MJJASO), and winter (NDJFMA) for the entire Himalaya. Additionally, we calculate a differential EVI that compares summer versus winter vegetation density (MJJASO/NDJFMA). A decrease in vegetation density is observed from east to west, with the greatest difference in winter vegetation cover (225% higher in the eastern than western Himalaya). In contrast, differential EVI is higher in the western Himalaya, increasing 170% from east to west. To evaluate the effect of vegetation on denudation and landscape evolution, we combine the 14-year EVI data, topographic analysis, and a compilation of >100 published and unpublished 10-Be terrestrial cosmogenic nuclide (TCN) catchment-mean denudation rates from across the Himalaya

  20. Life and Work of Academician Momir Polenakovic.

    PubMed

    Kambovski, Vlado

    2015-01-01

    Talking about Acad. Momir Polenakovic, on the occasion of his 75th anniversary and 50 years of work, it is my pleasure to say that he is one of the rare medical workers, researchers, visionaries and educators, especially in the field of nephrology. With his work he became famous in Macedonia and in the world and raised the Macedonian nephrology to a European level. He is characterized with the highest virtues of the scientist: knowledge, diligence, searching for truth and empathy. Acad. Polenakovic is an example to all younger counterparts for his exceptionally correct and friendly relations with all his associates, and, he also supports his younger colleagues in their work and development. PMID:27442371

  1. Computing Beyond the Church-Turing Limit

    NASA Astrophysics Data System (ADS)

    Jones, Robert

    2009-05-01

    Dershowitz and Gurevich claim to have proven the Church-Turing theorem starting from a set of 4 reasonable postulates. (Bulletin of Symbolic Logic, vol. 14, num. 3, Sept. 2008, pg. 299) But their postulate II assumes fixed vocabulary. Humans, however, change their vocabulary words (and concepts) over time. My Asa H artificial intelligence also changes its vocabulary. (Trans. of the Kansas Acad. of Sci., vol. 109, no. 3/4, pg 159, 2006, www.bioone.org/archive/0022- 8443/109/3/pdf/i0022-8443-109-3-159.pdf) Their postulate I excludes nondeterministic transitions between states. I don't know how often humans flip a coin but my Asa H does employ random transitions under certain circumstances. Perhaps humans and Asa H go beyond the Church-Turing limit. (Trans. Kansas Acad. of Sci., 108, 3/4, pg. 169, 2005)

  2. [Rene Leriche, pioneer of modern surgery].

    PubMed

    Germain, Michel A

    2008-01-01

    René Leriche (1879-1955) is not unknowned, but he has an important place in surgery. He is one of the glory of the contemporary surgery. He has dominated the French surgery during more than thirty years. The life of Leriche is specified: Lyon, medical career, marriage, military service, first world war, Strasbourg, Collage de France, second world war, Académie des Sciences; he was president of the Académie de Chirurgie, chief of the surgical department of the American Hospital; retirement, and death. His scientific work is eminent: surgery of pain, of the sympathic system, vascular surgery, experimental surgery, medical teaching in France, and the Ordre des Mêdecins. Leriche was a fervent patriot and served France to the best of his ability in peace, in war and during occupation by the enemy.

  3. Reconciling disagreement over climate–conflict results in Africa

    PubMed Central

    Hsiang, Solomon M.; Meng, Kyle C.

    2014-01-01

    A recent study by Burke et al. [Burke M, Miguel E, Satyanath S, Dykema J, Lobell D (2009) Proc Natl Acad Sci USA 106(49):20670–20674] reports statistical evidence that the likelihood of civil wars in African countries was elevated in hotter years. A following study by Buhaug [Buhaug H (2010) Proc Natl Acad Sci USA 107(38):16477–16482] reports that a reexamination of the evidence overturns Burke et al.’s findings when alternative statistical models and alternative measures of conflict are used. We show that the conclusion by Buhaug is based on absent or incorrect statistical tests, both in model selection and in the comparison of results with Burke et al. When we implement the correct tests, we find there is no evidence presented in Buhaug that rejects the original results of Burke et al. PMID:24520173

  4. Debye Shielding

    NASA Astrophysics Data System (ADS)

    Jones, Robert

    2011-10-01

    We usually expect that a biased electrode in contact with a plasma will effect only its immediate surroundings. The plasma will tend to shield itself from the applied electric potential, the characteristic shielding distance being the Debye length. This is not the case for biased gun electrodes which can project a nonneutral plasma beam relatively long distances across a magnetically confined plasma (Controlling the plasma potential across a magnetic field, Trans. Kansas Acad. Sci., vol 93, pg 125, R. Jones, 1990 and Plasma heating with electrically biased plasma guns, Trans. Kansas Acad. Sci., vol 97, pg 136, R. Jones, 1994) See also my website www.robert-w-jones.com and blog www.robertwilliamjones.blogspot.com.

  5. Stomatocyte–discocyte–echinocyte sequence of the human red blood cell: Evidence for the bilayer– couple hypothesis from membrane mechanics

    PubMed Central

    Lim H. W., Gerald; Wortis, Michael; Mukhopadhyay, Ranjan

    2002-01-01

    Red-cell shape is encoded in the mechanical properties of the membrane. The plasma membrane contributes bending rigidity; the protein-based membrane skeleton contributes stretch and shear elasticity. When both effects are included, membrane mechanics can reproduce in detail the full stomatocyte–discocyte–echinocyte sequence by variation of a single parameter related to the bilayer couple originally introduced by Sheetz and Singer [Sheetz, M. P. & Singer, S. J. (1974) Proc. Natl. Acad. Sci. USA 71, 4457–4461]. PMID:12471152

  6. RNA Virus Evolution via a Fitness-Space Model

    NASA Astrophysics Data System (ADS)

    Tsimring, Lev S.; Levine, Herbert; Kessler, David A.

    1996-06-01

    We present a mean-field theory for the evolution of RNA virus populations. The theory operates with a distribution of the population in a one-dimensional fitness space, and is valid for sufficiently smooth fitness landscapes. Our approach explains naturally the recent experimental observation [I. S. Novella et al., Proc. Natl. Acad. Sci. U.S.A. 92, 5841-5844 (1995)] of two distinct stages in the growth of virus fitness.

  7. Selection-mutation process of RNA viruses

    NASA Astrophysics Data System (ADS)

    Aafif, Amal; Lin, Juan

    1998-02-01

    RNA viruses mutate at a rate 105-106 times faster than their DNA counterparts. This process can be simulated by a continuous stochastic model on a smooth one-dimensional fitness landscape where selection forces the viral quasispecies to climb uphill to higher fitness values. Theoretical results of the model with drift velocity proportional to fitness are fitted to the experimental observations made by Novella et al. [Proc. Natl. Acad. Sci. U.S.A. 92, 5841 (1995)].

  8. Delisle, Joseph-Nicolas (fl. eighteenth century)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    French astronomer, member of the Académie, hired CHARLES MESSIER as a draftsman, and as a recorder of astronomical observations. Visited ISAAC NEWTON in London in 1724. Calculated the return path for HALLEY's Comet in 1758-9 and published a map which guided the recovery search, showing the predicted path of return calculated at 10 day intervals. Messier, as his observing assistant, was set to obs...

  9. [Burnout effect on academic progress of Oncology medical residents].

    PubMed

    González-Ávila, Gabriel; Bello-Villalobos, Herlinda

    2014-01-01

    Introducción: en el periodo formativo de los cursos de especializaciones médicas se asumen nuevas y grandes responsabilidades en el ámbito profesional y personal. La interacción de diferentes factores que envuelven el ejercicio de estos médicos puede llegar a sobrepasar su capacidad de afrontamiento y ocasionarles niveles elevados de estrés y desgaste profesional, lo cual afectará su desarrollo académico. El objetivo es determinar si el estrés laboral presente en los médicos residentes afecta su aprovechamiento académico. Métodos: se aplicó el cuestionario de Maslach a 52 médicos residentes de tres especialidades oncológicas que aceptaron participar voluntariamente el día que acudieron a su tercer examen ordinario del área cognoscitiva. Resultados: la prevalencia de burnout fue del 13.5 % con una frecuencia mayor en el primer año de la especialidad. En sus dimensiones, se encontró un mayor agotamiento emocional y baja realización personal en Oncología Médica. El aprovechamiento académico fue mayor para el tercer año de la residencia, con una diferencia significativa para Cirugía Oncológica y Oncología Médica (p = 0.026 y 0.015, respectivamente). No obstante, no se observó relación alguna con la presencia de burnout, ni tampoco con sexo (p = 0.437), estado civil (p = 0.329), número de hijos (p = 0.467) o escolaridad de la pareja (p = 0.784). Conclusión: la presencia de burnout no afecta el aprovechamiento académico de los médicos residentes en oncología.

  10. To be a priest should to know astronomy...

    NASA Astrophysics Data System (ADS)

    de Alba-Martinez, D. J.

    2002-12-01

    In spite of that recently some academic programs try to join science and religion themes in the same course, was during nineteenth century that was necessary to study astronomy for those that want to be catholic priest in Jalisco State, Mexico. A brief description on this astronomy courses is shown and some products from this activity and persons that were involved. This work was partially supported by Coord. de Servs. Acad.-CUCEI, Universidad de Guadalajara.

  11. Unobserved time effects confound the identification of climate change impacts.

    PubMed

    Auffhammer, Maximilian; Vincent, Jeffrey R

    2012-07-24

    A recent study by Feng et al. [Feng S, Krueger A, Oppenheimer M (2010) Proc Natl Acad Sci USA 107:14257-14262] in PNAS reported statistical evidence of a weather-driven causal effect of crop yields on human migration from Mexico to the United States. We show that this conclusion is based on a different statistical model than the one stated in the paper. When we correct for this mistake, there is no evidence of a causal link. PMID:22783021

  12. Memory neuron: synapse microchemistry for the memory component of a neuroconnective brain model.

    PubMed Central

    Wooldridge, D E

    1980-01-01

    This paper examines the synaptic microchemistry required if a memory neuron is to have the operating characteristics previously attributed to it [Wooldridge, D.E. (1980) Proc. Natl. Acad. Sci. USA, 77,2305-2308]. It is concluded that the requirements can be met by a combination of membrane mechanisms not very different from those that are commonly postulated to explain the properties of known types of neurons. PMID:6248883

  13. Study protocol: münster tinnitus randomized controlled clinical trial-2013 based on tailor-made notched music training (TMNMT)

    PubMed Central

    2014-01-01

    Background Tinnitus is a result of hyper-activity/hyper-synchrony of auditory neurons coding the tinnitus frequency, which has developed to synchronous mass activity owing the lack of inhibition. We assume that removal of exactly these frequency components from an auditory stimulus will cause the brain to reorganize around tonotopic regions coding the tinnitus frequency. Based on this assumption a novel treatment for tonal tinnitus - tailor-made notched music training (TMNMT) (Proc Natl Acad Sci USA 107:1207–1210, 2010; Ann N Y Acad Sci 1252:253–258, 2012; Frontiers Syst Neurosci 6:50, 2012) has been introduced and will be tested in this clinical trial on a large number of tinnitus patients. Methods and design A randomized controlled trial (RCT) in parallel group design will be performed in a double-blinded manner. The choice of the intervention we are going to apply is based on two “proof of concept” studies in humans (Proc Natl Acad Sci USA 107:1207–1210, 2010; Ann N Y Acad Sci 1252:253–258, 2012; Frontiers Syst Neurosci 6:50, 2012; PloS One 6(9):e24685, 2011) and on a recent animal study (Front Syst Neurosci 7:21, 2013). The RCT includes 100 participants with chronic, tonal tinnitus who listened to tailor-made notched music (TMNM) for two hours a day for three months. The effect of TMNMT is assessed by the tinnitus handicap questionnaire and visual analogue scales (VAS) measuring perceived tinnitus loudness, distress and handicap. Discussion This is the first randomized controlled trial applying TMNMT on a larger number of patients with tonal tinnitus. Our data will verify more securely and reliably the effectiveness of this kind of completely non-invasive and low-cost treatment approach on tonal tinnitus. Trial registration Current Controlled Trials ISRCTN04840953 PMID:24581050

  14. Network analysis of human heartbeat dynamics

    NASA Astrophysics Data System (ADS)

    Shao, Zhi-Gang

    2010-02-01

    We construct the complex networks of human heartbeat dynamics and investigate their statistical properties, using the visibility algorithm proposed by Lacasa and co-workers [Proc. Natl. Acad. Sci. U.S.A. 105, 4972 (2008)]. Our results show that the associated networks for the time series of heartbeat interval are always scale-free, high clustering, hierarchy, and assortative mixing. In particular, the assortative coefficient of associated networks could distinguish between healthy subjects and patients with congestive heart failure.

  15. Supercompact cardinals, sets of reals, and weakly homogeneous trees.

    PubMed

    Woodin, W H

    1988-09-01

    It is shown that if there exists a supercompact cardinal then every set of reals, which is an element of L(R), is the projection of a weakly homogeneous tree. As a consequence of this theorem and recent work of Martin and Steel [Martin, D. A. & Steel, J. R. (1988) Proc. Natl. Acad. Sci. USA 85, 6582-6586], it follows that (if there is a supercompact cardinal) every set of reals in L(R) is determined. PMID:16593979

  16. [Life style and monitoring of the dietary intake of students at the Melilla campus of the University of Granada].

    PubMed

    Navarro-Prado, Silvia; González-Jiménez, Emilio; Montero-Alonso, Miguel A; López-Bueno, Marta; Schmidt-RioValle, Jacqueline

    2015-06-01

    Introducción: los estudiantes universitarios representan un colectivo social en riesgo desde el punto de vista nutricional, ya que a menudo mantienen estilos de vida y hábitos nutricionales inapropiados. Objetivos: analizar el estilo de vida de los alumnos del Campus de la Universidad de Granada en Melilla. Analizar la evolución de los hábitos alimentarios de los estudiantes del campus durante el curso académico 2013-2014. Material y método: se realizó un estudio longitudinal durante el curso académico 2013-2014 en el cual, a su inicio, se evaluó el estilo de vida y, de forma continuada los hábitos nutricionales de un grupo representativo de 257 estudiantes, 90 chicos (35%) y 167 chicas (65%), todos ellos del campus de la Universidad de Granada en la Ciudad Autónoma de Melilla (norte de África). Resultados: los hábitos nutricionales empeoran a medida que avanza el curso académico, caracterizándose por una reducción significativa (p < 0.001) en la ingesta de carbohidratos, así como por una elevación significativa (p < 0.001) en la ingesta proteica y lipídica, siendo especialmente rica en grasas saturadas y baja en fibra. Conclusiones: la población estudiada posee un estilo de vida eminentemente sedentario. A medida que avanza el curso académico, los hábitos nutricionales de los estudiantes empeoran, alejándose del patrón de alimentación mediterráneo con el consiguiente riesgo de desarrollar enfermedades metabólicas y cardiovasculares. De estos resultados se desprende la necesidad de continuar profundizando a fin de identificar los factores que influyen en sus hábitos nutricionales y establecer las medidas correctoras oportunas.

  17. Clinical Indicators of Child Development in the Capitals of Nine Brazilian States: The Influence of Regional Cultural Factors

    PubMed Central

    de Carvalho, André Laranjeira; da Silva, Luiz Fernando Ferraz; Grisi, Sandra Josefina Ferraz Ellero; de Ulhôa Escobar, Ana Maria

    2008-01-01

    OBJECTIVE Evaluating the interaction between mother or caregiver and infant through the Clinical Indicators of Risks in Infant Development and investigating whether local and cultural influences during infant development affect these clinical indicators. INTRODUCTION The Clinical Indicators of Risks in Infant Development was created in order to fully assess infants’ development and the subjective relationship between the babies and their caregivers. The absence of two or more Clinical Indicators of Risks in Infant Developments suggests a possibly inadequate mental development. Given the continental size of Brazil and its accentuated cultural differences, one might question how trustworthy these indicators can be when applied to each of the geographical regions of the country. METHODS This was a cross-sectional study with 737 infants from the capitals of 9 Brazilian states. The size of the initial sample population was based on a pilot study carried out in the cities of São Paulo and Brasília. The ages of children were grouped: 0–3 months, 4–7 months, 8–11 months and 12–18 months. The chi-square test was used together with analyses by the statistical software SPSS 13.0. RESULTS Statistical analysis of results from the different municipalities against the total sample did not reveal any statistically significant differences. Municipalities represented were Belém (p=0.486), Brasília (p=0.371), Porto Alegre (p=0.987), Fortaleza (p=0.259), Recife (p=0.630), Salvador (0.370), São Paulo (p=0.238), Curitiba (p=0.870), and Rio de Janeiro (p= 0.06). DISCUSSION Care for mental development should be considered a public health issue. Its evaluation and follow-up should be part of the already available mother-child assistance programs, which would then be considered to provide “full” care to children. CONCLUSIONS Local habits and culture did not affect the results of the Clinical Indicators of Risks in Infant Development indicators. Clinical Indicators of

  18. The New Microbiology: a conference at the Institut de France.

    PubMed

    Radoshevich, Lilliana; Bierne, Hélène; Ribet, David; Cossart, Pascale

    2012-08-01

    In May 2012, three European Academies held a conference on the present and future of microbiology. The conference, entitled "The New Microbiology", was a joint effort of the French Académie des sciences, of the German National Academy of Sciences Leopoldina and of the British Royal Society. The organizers - Pascale Cossart and Philippe Sansonetti from the "Académie des sciences", David Holden and Richard Moxon from the "Royal Society", and Jörg Hacker and Jürgen Hesseman from the "Leopoldina Nationale Akademie der Wissenschaften" - wanted to highlight the current renaissance in the field of microbiology mostly due to the advent of technological developments and allowing for single-cell analysis, rapid and inexpensive genome-wide comparisons, sophisticated microscopy and quantitative large-scale studies of RNA regulation and proteomics. The conference took place in the historical Palais de l'Institut de France in Paris with the strong support of Jean-François Bach, Secrétaire Perpétuel of the Académie des sciences.

  19. Electrochemical Characterization of Escherichia coli Adaptive Response Protein AidB

    PubMed Central

    Hamill, Michael J.; Jost, Marco; Wong, Cintyu; Bene, Nicholas C.; Drennan, Catherine L.; Elliott, Sean J.

    2012-01-01

    When exposed to known DNA-damaging alkylating agents, Escherichia coli cells increase production of four DNA repair enzymes: Ada, AlkA, AlkB, and AidB. The role of three enzymes (Ada, AlkA, and AlkB) in repairing DNA lesions has been well characterized, while the function of AidB is poorly understood. AidB has a distinct cofactor that is potentially related to the elusive role of AidB in adaptive response: a redox active flavin adenine dinucleotide (FAD). In this study, we report the thermodynamic redox properties of the AidB flavin for the first time, both for free protein and in the presence of potential substrates. We find that the midpoint reduction potential of the AidB flavin is within a biologically relevant window for redox chemistry at −181 mV, that AidB significantly stabilizes the flavin semiquinone, and that small molecule binding perturbs the observed reduction potential. Our electrochemical results combined with structural analysis allow for fresh comparisons between AidB and the homologous acyl-coenzyme A dehydrogenase (ACAD) family of enzymes. AidB exhibits several discrepancies from ACADs that suggest a novel catalytic mechanism distinct from that of the ACAD family enzymes. PMID:23443126

  20. [Felix Vicq d'Azyr, founder of the Academy of Medicine (1748-1794)].

    PubMed

    Sournia, J C

    1994-10-01

    Vicq d'Azyr (1748-1794) was the son of a norman physician. He was graduated at the Paris university and obtained quickly a brilliant renown and career. During his whole life he continued studies on human and animal anatomy. Member of Académie des sciences and Académie française, he was the queen's physician, superintendent for epidemies, and above all general secretary of the Société royale de médecine. In that position he kept a regular correspondence with a great number of physicians and surgeons in the Kingdom. They gave the Société informations about epidemies and epizooties in relation with the climate, about economic resources of the population, the quality of food supplies, the ability of health professionals, etc. The amount of the informations so collected during sixteen years is considerable. Vicq d'Azyr also worked out a plan for setting up the medicine in the country. That plan was based on public physicians in countries, districts and departments, giving an "academic body" an account of their task. His vow was satisfied in 1820 when the Académie royale de médecine was founded.

  1. An alternative technique for the computation of the designator in the retinex theory of color vision.

    PubMed

    Land, E H

    1986-05-01

    Accepting the first postulate of the retinex theory of color vision that there are three independent lightness-determining mechanisms (one for long waves, one for middle waves, and one for short waves), each operative with less than a millisecond exposure and each served by its own retinal pigment, a basic task of retinex theory becomes the determination of the nature of these mechanisms. Earlier references proposed several workable algorithms. [Land, E. H. (1959) Proc. Natl. Acad. Sci. USA 45, 115-129; Land, E. H. (1959) Proc. Natl. Acad. Sci. USA 45, 636-644; Land, E. H. (1983) Proc. Natl. Acad. Sci. USA 80, 5163-5169; Land, E. H. & McCann, J. J. (1971) J. Opt. Soc. Am. 61, 1-11; Land, E. H. (1986) Vision Res. 26, 7-21.] The present paper describes a relatively simple alternative technique for the computation of the designator in retinex theory and reports the general operational effectiveness of the new technique, including the competence, not possessed by earlier algorithms, for generating Mach bands. PMID:3458165

  2. High-contrast imaging with an arbitrary aperture: Active compensation of aperture discontinuities

    SciTech Connect

    Pueyo, Laurent; Norman, Colin

    2013-06-01

    We present a new method to achieve high-contrast images using segmented and/or on-axis telescopes. Our approach relies on using two sequential deformable mirrors (DMs) to compensate for the large amplitude excursions in the telescope aperture due to secondary support structures and/or segment gaps. In this configuration the parameter landscape of DM surfaces that yield high-contrast point-spread functions is not linear, and nonlinear methods are needed to find the true minimum in the optimization topology. We solve the highly nonlinear Monge-Ampere equation that is the fundamental equation describing the physics of phase-induced amplitude modulation. We determine the optimum configuration for our two sequential DM system and show that high-throughput and high-contrast solutions can be achieved using realistic surface deformations that are accessible using existing technologies. We name this process Active Compensation of Aperture Discontinuities (ACAD). We show that for geometries similar to the James Webb Space Telescope, ACAD can attain at least 10{sup –7} in contrast and an order of magnitude higher for both the future extremely large telescopes and on-axis architectures reminiscent of the Hubble Space Telescope. We show that the converging nonlinear mappings resulting from our DM shapes actually damp near-field diffraction artifacts in the vicinity of the discontinuities. Thus, ACAD actually lowers the chromatic ringing due to diffraction by segment gaps and struts while not amplifying the diffraction at the aperture edges beyond the Fresnel regime. This outer Fresnel ringing can be mitigated by properly designing the optical system. Consequently, ACAD is a true broadband solution to the problem of high-contrast imaging with segmented and/or on-axis apertures. We finally show that once the nonlinear solution is found, fine tuning with linear methods used in wavefront control can be applied to further contrast by another order of magnitude. Generally speaking

  3. Relationship between academic performance, psychological well-being, and coping strategies in medical students.

    PubMed

    Trucchia, Silvina M; Lucchese, Marcela S; Enders, Julio E; Fernández, A Ruth

    2013-01-01

    Introducción: El rendimiento académico es producto del complejo mundo que envuelve al estudiante, determinado por aspectos cotidianos (intensidad de estudio, motivación y medio relacional) que afectan el desempeño académico de los individuos. Otros factores pueden ser psicológicos o emocionales tales como la ansiedad, el grado de bienestar psicológico y las estrategias conductuales tendientes a lograr una adaptación efectiva a las demandas concretas del ambiente y al estrés emocional asociado. Objetivos: En esta investigación se propuso identificar el nivel de bienestar psicológico y las estrategias de afrontamiento en los estudiantes del Ciclo Básico de la Carrera de Medicina y analizar la relación entre bienestar, afrontamiento y rendimiento académico. Material y método: Es un estudio observacional el cual se trabajó a partir del “Cuestionario Determinantes relacionados con el rendimiento académico” implementado a 374 alumnos. El análisis de los datos se efectuó a través del procesamiento estadístico con análisis bivariado (p<0,05) y análisis factorial de correspondencia múltiple. Resultados: Los alumnos con “Rendimiento MB/B” presentan altos niveles de satisfacción y bienestar utilizando un afrontamiento directo que contribuye a “enfrentar las situaciones que preocupan” mediante la “solución de problemas”. En tanto que los alumnos con “Rendimiento R/I” perciben “disgusto con la mayoría de los aspectos de su personalidad” sintiéndose impedidos para responder satisfactoriamente a las demandas del ambiente, asumiendo “comportamientos de evitación” como forma de afrontamiento. Conclusiones: El rendimiento académico de los estudiantes se asocia con la presencia de bienestar psicológico, satisfacción con respecto a los logros alcanzados y el afrontamiento de situaciones estresoras.

  4. [Implementation of the academic day for undergraduate interns].

    PubMed

    Salas-Flores, Ricardo; González-Pérez, Brian

    2016-01-01

    Introducción: el internado médico de pregrado es una etapa fundamental en la formación del médico general, en la cual el alumno pasa a ser integrante del equipo de salud y pone en práctica los conocimientos adquiridos durante los primeros años de la carrera. El objetivo fue evaluar el impacto de la implementación del día académico en médicos internos de pregrado del Hospital General Regional No. 6 “Dr. Ignacio García Téllez” de segundo nivel de atención médica. Métodos: estudio comparativo y prospectivo efectuado en una muestra de 56 médicos internos de pregrado que participaron en la implementación del día académico. El impacto de este día fue evaluado por la calificación obtenida en el examen de los diferentes módulos aplicado al inicio y al finalizar el internado de pregrado. Para el análisis estadístico se utilizó la prueba no paramétrica de Wilcoxon para la comparación intragrupo de los resultados iniciales con los finales. Resultados: en las calificaciones obtenidas en el examen aplicado al inicio y al final de la implementación del día académico se observó una diferencia positiva en los módulos de Medicina Interna, Pediatría, Ginecología y Obstetricia, Urgencias, Cirugía General y Medicina Familiar al término del día académico (p = 0.000). Conclusiones: se deben establecer las líneas para realizar intervenciones educativas desde la perspectiva activo-participativa, como el día académico, para incrementar el desarrollo del aprendizaje significativo que repercutirá positivamente en la calidad de la atención de los pacientes.

  5. The movement of the trunk and breast during front crawl and breaststroke swimming.

    PubMed

    Mills, Chris; Lomax, Mitch; Ayres, Bessie; Scurr, Joanna

    2015-01-01

    Breast displacement has been investigated in various activities to inform bra design, with the goal of minimising movement; however, breast motion during swimming has yet to be considered. The aim was to investigate trunk and breast kinematics whilst wearing varying levels of breast support during two swimming strokes. Six larger-breasted females swam front crawl and breaststroke (in a swimming flume), in three breast support conditions while three video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated. Greater breast displacement occurred mediolaterally in the swimsuit condition (7.8, s = 1.5 cm) during front crawl and superioinferiorly in the bare-breasted condition (3.7, s = 1.6 cm) during breaststroke, with the sports bra significantly reducing breast displacements. During front crawl, the greatest trunk roll occurred in the sports bra condition (43.1, s = 8.3°) and during breaststroke greater trunk extension occurred in the swimsuit condition (55.4, s = 5.0°); however, no differences were found in trunk kinematics between the three breast support conditions. Results suggest that the swimsuit was ineffective as a means of additional support for larger-breasted women during swimming; incorporating design features of sports bras into swimsuits may improve the breast support provided. PMID:25189996

  6. 3-D breast anthropometry of plus-sized women in South Africa.

    PubMed

    Pandarum, Reena; Yu, Winnie; Hunter, Lawrance

    2011-09-01

    Exploratory retail studies in South Africa indicate that plus-sized women experience problems and dissatisfaction with poorly fitting bras. The lack of 3-D anthropometric studies for the plus-size women's bra market initiated this research. 3-D body torso measurements were collected from a convenience sample of 176 plus-sized women in South Africa. 3-D breast measurements extracted from the TC(2) NX12-3-D body scanner 'breast module' software were compared with traditional tape measurements. Regression equations show that the two methods of measurement were highly correlated although, on average, the bra cup size determining factor 'bust minus underbust' obtained from the 3-D method is approximately 11% smaller than that of the manual method. It was concluded that the total bust volume correlated with the quadrant volume (r = 0.81), cup length, bust length and bust prominence, should be selected as the overall measure of bust size and not the traditional bust girth and the underbust measurement. STATEMENT OF RELEVANCE: This study contributes new data and adds to the knowledge base of anthropometry and consumer ergonomics on bra fit and support, published in this, the Ergonomics Journal, by Chen et al. (2010) on bra fit and White et al. (2009) on breast support during overground running.

  7. Striped-tailed Yellow-finch nesting success in abandoned mining pits from central Brazilian cerrado.

    PubMed

    Gressler, D T; Marini, M Â

    2015-01-01

    Suitability of degraded areas as breeding habitats can be tested through assessment of nest predation rates. In this study we estimated nest success in relation to several potential predictors of nest survival in the Stripe-tailed Yellow-finch (Sicalis citrina) breeding in abandoned mining pits at Brasília National Park. We monitored 73 nests during the 2007-breeding season. Predation was the main cause of nest failure (n = 48, 66%); while six nests were abandoned (8%) and 19 nests produced young (26%). Mayfield's daily survival rates and nest success were 0.94 and 23%, respectively. Our results from nest survival models on program MARK indicated that daily survival rates increase linearly towards the end of the breeding season and decrease as nests aged. None of the nest individual covariates we tested - nest height, nest size, nest substrate, and edge effect - were important predictors of nest survival; however, nests placed on the most common plant tended to have higher survival probabilities. Also, there was no observer effect on daily survival rates. Our study suggests that abandoned mining pits may be suitable alternative breeding habitats for Striped-tailed Yellow-finches since nest survival rates were similar to other studies in the central cerrado region.

  8. SHADOW: a new welding technique

    NASA Astrophysics Data System (ADS)

    Kramer, Thorsten; Olowinsky, Alexander M.; Durand, Friedrich

    2002-06-01

    The new welding technique 'SHADOW ' is introduced. SHADOW means the use of a single pulse to generate a quasi continuous weld of several millimeters in length. HET processing time is defined by the pulse duration of the pulsed laser. At present, a state-of-the-art laser is capable of a maximum pulse duration of 20 ms. The variation of the laser power depend on time is a vital capability of the pulsed laser to adapt the energy deposition into the workpiece. Laser beam welds of several watch components were successfully performed. Similar metals like crowns and axes made out of stainless steel have been welded using pulsed laser radiation. Applying a series of about 130 single pulses for the crown-axis combination the total energy accumulates to 19.5 J. The use of the SHADOW welding technique reduces the energy to 2.5 J. While welding dissimilar metals like stainless steel and bras, the SHADOW welding reduces drastically the contamination as well as the distortion. Laser beam welding of copper has a low process reliability due to the high reflection and the high thermal conductivity. SHADOW welds of 3.6 mm length were performed on 250 micrometers thick copper plates with very high reproducibility. As a result, a pilot plant for laser beam welding of copper plates has been set up. The work to be presented has partly been funded by the European Commission in a project under the contract BRPR-CT-0634.

  9. [Genetic variability of the Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) in vegetable crops in São Luís, state of Maranhão, Brazil].

    PubMed

    Da Silva, Maria C; De Lemos, Raimunda N S; Lima, Luzia H C; Gourlart Filho, Luiz R; Pereira, Silma R F

    2009-01-01

    The RAPD technique is widely used to investigate the distinct genetic characteristics of the complex Bemisia tabaci (Gennadius), which is currently constituted of approximately 41 biotypes. The objective of this research was to characterize populations of whitefly collected in crops of agricultural producing areas in São Luís, MA, like okra, beans and pepper, using RAPD molecular markers. Females from nine whitefly populations were analyzed and compared with B. tabaci biotype B taken from poinsettia culture of Embrapa Genetic Resources and Biotechnology (Brasília, DF). Twelve out of the 20 primers tested produced specific band patterns suitable to confirm that the evaluated specimens belong to the biotype B of B. tabaci, despite the high percentage of detected polymorphism. The analysis of the 96 RAPD molecular markers generated indicated that the populations on okra, beans and pepper were grouped according to the host cultures, sharing 80, 76 and 45% of genetic similarity, respectively, when compared with the control population of B. tabaci biotype B. A lower selective pressure was observed with the population of whitefly collected on pepper and minor genetic variability in the whitefly populations collected on okra and bean, when compared with the control population. PMID:20098922

  10. Prevalence of hypodontia in orthodontic patients in Brasilia, Brazil.

    PubMed

    Gomes, Raquel Ribeiro; da Fonseca, Janaína Aparecida Calaça; Paula, Lílian Marly; Faber, Jorge; Acevedo, Ana Carolina

    2010-06-01

    The purpose of this retrospective study was to determine the prevalence of hypodontia and associated dental anomalies in patients undergoing orthodontic treatment in Brasília, Brazil, over a 2 year period (1998-2000). The records of 1049 orthodontic patients between 10 and 15.7 years of age (507 males and 542 females) from 16 orthodontic clinics were analysed. Descriptive statistics were performed for the study variables. A chi-square test was used to determine the difference in the prevalence of hypodontia between genders. The prevalence of hypodontia was 6.3 per cent (39.4 per cent males and 60.6 per cent females) with no statistically significant difference between the genders. One case of oligodontia was observed. The maxillary lateral incisor was the most frequently missing tooth, followed by the mandibular second premolar. All cases of hypodontia, except one, were associated with at least one other dental anomaly. These associated dental anomalies were retained primary teeth (30.3 per cent), ectopic canine eruption (25.8 per cent), taurodontism (21.2 per cent), and peg-shaped maxillary lateral incisors (16.7 per cent). PMID:19837747

  11. Tectono-stratigraphic terranes in Cape Breton Island, Nova Scotia: Implications for the configuration of the northern Appalachian orogen

    SciTech Connect

    Barr, S.M.; Raeside, R.P. )

    1989-09-01

    Cape Breton Island is divided into four terranes on the basis of contrasts in pre-Carboniferous geology. The Blair River Complex in the north is an exposure of North American Grenvillian basement, analogous to the Humber zone basement in Newfoundland. Ordovician to Devonian metavolcanic, metasedimentary, gneissic, and granitic rocks of the Aspy terrane are correlative with parts of the Gander terrane of Newfoundland and New Brunswick. The Bras d'Or terrane, characterized by low-pressure gneisses, a carbonate-clastic platform sequence, and later Precambrian-Early Cambrian plutons, may be correlative with units previously included in the Gander terrane in southern Newfoundland and the Avalon terrane in southern New Brunswick. The Mira terrane in southeastern Cape Breton Island, including late Precambrian to Early Cambrian volcanic and sedimentary sequences and fossiliferous Cambrian-Ordovician units, is clearly part of the Avalon terrane. Therefore, with the exception of the Dunnage terrane, which is not represented in Cape Breton Island, the terranes of Newfoundland continue through Cape Breton Island. They are offset to the northwest to the mainland part of the Appalachian orogen in New Brunswick.

  12. Income evaluation of small - scale fishers in two Brazilian urban reservoirs: Represa Billings (SP) and Lago Paranoá (DF).

    PubMed

    Petrere, M; Walter, T; Minte-Vera, C V

    2006-08-01

    The income of small-scale fisheries of two urban reservoirs in Brazil: Represa Billings (127 km2) located in the metropolitan region of São Paulo, the capital city of the state of São Paulo and Lago Paranoá (38 km2) located in Brasília (DF), the capital city of Brazil were calculated and compared. Both fisheries are mainly based on the alien Nile tilapia Oreochromis niloticus (more than 80% of the total catch). Although these reservoirs are nearly 900 km apart, their native fish fauna belong to the Upper Paraná Province. The Represa Billings fishers have, on average, a daily profit of 15.8 R dollars (8.4 U dollars mostly employing gill nets) and Lago Paranoá fishers 46.6 R dollars (24.9 U dollars, mostly employing cast nets), which is a statistically significant difference (P < 0.001). The profit of the fisheries is explained by the factor "reservoir" and covariate "days of fishing". Due to the increasing violence in the metropolitan region of São Paulo, the Represa Billings fishery is vanishing.

  13. Communicating astronomy in a small island state: The unique role of the Mauritius Radio Telescope

    NASA Astrophysics Data System (ADS)

    Saddul-Hauzaree, S.

    2008-06-01

    The Mauritius Radio Telescope (MRT) is a 2 km x 1 km T-shaped aperture synthesis array that can generate radio images of the southern sky at 151.6 MHz. The sky surveyed can be in the declination range of -70o to -10o. It is located at Bras d'Eau, northeast of Mauritius at latitude 20oS and longitude 60oE. The MRT is a joint project of the University of Mauritius, the Indian Institute of Astrophysics and the Raman Research Institute. One of the main objectives of the MRT is to generate public interest in astronomy. Thus, it is involved in a wide range of onsite outreach activities for young school children. More mature students visiting the telescope learn about sky observation with a radio telescope, get to explore some sets of data, interact with the scientific personnel, get the opportunity to have hands-on experience with image manipulation and can ask a lot of questions on astronomy. This poster gives an overview of the Mauritius Radio Telescope and the attempts of MRT ito communicate astronomy to students as a process and not just as a vast expanse of knowledge. The challenges and dilemmas faced by MRT in conveying astronomy to the general public in a small island state are investigated and presented.

  14. Are opossums a relevant factor associated with asymptomatic Leishmania infection in the outskirts of the largest Brazilian cities?

    PubMed

    Carranza-Tamayo, César Omar; Werneck, Guilherme Loureiro; Romero, Gustavo Adolfo Sierra

    2016-01-01

    A population survey was conducted to explore the prevalence and factors associated with Leishmania infection in the Fercal region of the Federal District. The Fercal region is a group of neighborhoods in Brasília in which the first cases of visceral leishmaniasis were described. Leishmania infection was established by a positive leishmanin test. Although other tests were performed in the study (an immunochromatographic assay (Kalazar detect(®)) and a molecular assay), only the leishmanin skin test provided sufficient results for the measurement of the disease prevalence. Data on the epidemiological, clinical and environmental characteristics of individuals were collected along with the diagnostic tests. After sampling and enrollment, seven hundred people from 2 to 14 years of age were included in the study. The prevalence of Leishmania infection was 33.28% (95% CI 29.87-36.84). The factors associated with Leishmania infection according to the multivariate analysis were age of more than seven years and the presence of opossums near the home. Age is a known factor associated with Leishmania infection; however, the presence of wild animals, as described, is an understudied factor. The presence of opossums, which are known reservoirs of Leishmania, in peri-urban areas could be the link between the rural and urban occurrence of visceral leishmaniasis in the outskirts of largest Brazilian cities, as suggested by previous studies. PMID:26867473

  15. Implementation of a national metrology network of radionuclides used in nuclear medicine.

    PubMed

    dos Santos, Joyra A; Iwahara, Akira; Nícoli, Iêda G; Corrêa, Rosângela S; Alabarse, Frederico G; dos Santos, Carlos E L; Xavier, Ana M; Garcia, Eloy J; Tauhata, Luiz; Lopes, Ricardo T

    2006-01-01

    The Nuclear Medicine Services (NMS) in Brazil routinely use dose calibrators to measure the activity of solutions containing radiopharmaceuticals. These solutions are administered to patients with the intention to diagnose or treat illnesses. However, for optimal results, the activity of these radiopharmaceuticals must be determined as accurately as possible. The National Laboratory for Ionizing Radiation Metrology (LNMRI) led, since 1998, a comparison program for activity measurements of radiopharmaceuticals administered to patients in the NMS with the purpose promoting quality control. This program has been carried out successfully in Rio de Janeiro, but there is a need to implement it around the country. This can be resolved through the implementation of a network of regional laboratories at various locations throughout the national territory. Currently, such a network is active at a second site, located in Brasília, covering the needs of the Center-West Region, and at a third site, located in Porto Alegre, in the South Region. This work presents the results of comparisons for the radiopharmaceuticals nuclides 131I and 99Tcm and proves that the implementation of a radionuclide metrology network is feasible and viable.

  16. The influence of breast support on torso, pelvis and arm kinematics during a five kilometer treadmill run.

    PubMed

    Milligan, Alexandra; Mills, Chris; Corbett, Jo; Scurr, Joanna

    2015-08-01

    Many women wear sports bras due to positive benefits associated with these garments (i.e. reduction in breast movement and breast pain), however the effects these garments have on upper body running kinematics has not been investigated. Ten female participants (32 DD or 34 D) completed two five kilometer treadmill runs (9 km h(-1)), once in a low and once in a high breast support. The range of motion (ROM) and peak torso, pelvis, and upper arm Cardan joint angles were calculated over five gait cycles during a five kilometer run. Peak torso yaw, peak rotation of the pelvis, peak pelvis obliquity, ROM in rotation of the pelvis, and ROM in upper arm extension were significant, but marginally reduced when participants ran in the high breast support. The running kinematics reported in the high breast support condition more closely align with economical running kinematics previously defined in the literature, therefore, running in a high breast support may be more beneficial to female runners, with a high breast support advocated for middle distance runners.

  17. Seasonal variations in soil water in two woodland savannas of central Brazil with different fire history.

    PubMed

    Quesada, Carlos Alberto; Hodnett, Martin G; Breyer, Lacê M; Santos, Alexandre J B; Andrade, Sérgio; Miranda, Heloisa S; Miranda, Antonio Carlos; Lloyd, Jon

    2008-03-01

    Changes in soil water content were determined in two cerrado (sensu stricto) areas with contrasting fire history and woody vegetation density. The study was undertaken near Brasília, Brazil, from 1999 to 2001. Soil water content was measured with a neutron probe in three access tubes per site to a depth of 4.7 m. One site has been protected from fire for more than 30 years and, as a consequence, has a high density of woody plants. The other site had been frequently burned, and has a high herbaceous vegetation density and less woody vegetation. Soil water uptake patterns were strongly seasonal, and despite similarities in hydrological processes, the protected area systematically used more water than the burned area. Three temporarily contiguous patterns of water absorption were differentiated, characterized by variation in the soil depth from which water was extracted. In the early dry season, vegetation used water from throughout the soil profile but with a slight preference for water in the upper soil layers. Toward the peak of the dry season, vegetation had used most or all available water from the surface to a depth of 1.7 m, but continued to extract water from greater depths. Following the first rains, all water used was from the recently wetted upper soil layers only. Evaporation rates were a linear function of soil water availability, indicating a strong coupling of atmospheric water demand and the physiological response of the vegetation. PMID:18171664

  18. External breast prostheses in post-mastectomy care: women's qualitative accounts.

    PubMed

    Gallagher, P; Buckmaster, A; O'Carroll, S; Kiernan, G; Geraghty, J

    2010-01-01

    A good-quality external breast prosthesis and prosthesis-fitting service is an integral part of the recovery process post-mastectomy. However, this is an area of care that has minimal information or research available. The aim of this research was to investigate women's experience of the provision, fitting, supply and use of breast prostheses in Ireland. To ascertain women's own personal and subjective experiences, five focus groups with 47 women recruited through national cancer advocacy/support organizations and four Follow-up Breast Clinics throughout Ireland were conducted. As a result, five main themes emerged: (1) The fitting experience--Fitting? (2) Post-mastectomy products--Having? (3) Cost--Affording? (4) Information--Knowing? and (5) Adaptation--Accepting? The emerging themes pinpointed the impact of the fitting experience, fitting environment and the qualities of a prosthesis fitter on a woman's experience in obtaining a first or replacement breast prosthesis; the importance of the physical characteristics of the prosthesis and mastectomy bras; cost, affordability and entitlements; a lack of and perceived difficulty in getting information; and the myriad of personal and social impacts of a breast prosthesis for the woman. These findings are integral for the development of standards of practice in the fitting and supply of external breast prostheses in post-mastectomy care.

  19. A geometria do campo magnético na região da nuvem Lupus 1

    NASA Astrophysics Data System (ADS)

    Alves, F. P.; Franco, G. A. P.

    2003-08-01

    Apresentaremos os resultados de uma investigação polarimétrica na região de formação estelar junto à nuvem escura Lupus 1. Esse estudo baseia-se em polarimétria CCD obtida na banda R, e cobre Lupus 1, bem como a área vizinha a essa nuvem contendo a cavidade em 100 mm IRAS. Os dados observacionais foram coletados com o telescópio IAG de 60 cm do Observatório do Pico dos Dias (LNA/MCT - Brasópolis - MG). Nossa primeira análise mostra que uma variação da orientação do campo magnético através da região pode produzir padrões complexos de polarização cuja geometria do campo não pode ser facilmente determinada. Os padrões de polarização são inconsistentes com um campo magnético estritamente uniforme e unidimensional em larga escala. Comparação com a emissão em 100 mm mostra que localmente os vetores de polarização exibem um forte alinhamento com a orientação dos padrões observados em infravermelho.

  20. Le syndrome de Stewart-Treves compliquant un lymphœdème chronique idiopathique

    PubMed Central

    Safini, Fatima; Naim, Asmaa; Bouchbika, Zineb; Benchakroun, Nadia; Jouhadi, Hassan; Tawfiq, Nezha; Sahraoui, Souha; Benider, Abdellatif

    2014-01-01

    Le syndrome de Stewart-Treves (SST) est une entité rare, correspondant à un angiosarcome cutané compliquant un lymphoedème chronique. Il est de mauvais pronostic. Stewart et Treves ont rapportés en 1948, les premiers cas d'angiosarcome secondaire à un traitement du cancer du sein. Ce terme s'est généralisé pour regrouper l'ensemble des cas de lymphangiosarcome sur lymphoedème d'origine congénital héréditaire ou non héréditaire, post-traumatique ou post-infectieux. Le SST sur un lymphoedème idiopathique reste exceptionnel. Nous rapportons le cas rare d'une patiente présentant un lymphoedème chronique primitif idiopathique des quatre membres évoluant depuis l'adolescence et qui a développé un SST du membre supérieur droit. Elle a subi une amputation à mi- bras vu le caractère très évolué de la tumeur PMID:25883738

  1. Infrared Laser Stark Spectroscopy of the OH\\cdot\\cdot\\cdotCH3OH Complex Isolated in Superfluid Helium Droplets

    NASA Astrophysics Data System (ADS)

    Leavitt, Christopher M.; Brice, Joseph T.; Douberly, Gary E.; Hernandez, Federico J.; Pino, Gustavo A.

    2015-06-01

    The elimination of volatile organic compounds (VOCs) from the atmosphere is initiated by reactions with OH, NO3 and O3. For oxygenated VOCs, such as alcohols, ketones, ethers, etc., reactions occur nearly exclusively with the hydroxyl radical. Furthermore, the potential energy surfaces associated with reactions between OH and oxygenated VOCs generally feature a pre-reactive complex, stabilized by hydrogen bonding, which results in rate constants that exhibit large negative temperature dependencies. This was explicitly demonstrated recently for the OH + methanol (MeOH) reaction, where the rate constant increased by nearly two orders of magnitude when the temperature decreased from 200 K to below 70 K, highlighting the potential impact of this reaction in the interstellar medium (ISM). In this study, we trap this postulated pre-reactive complex formed between OH and MeOH using He nanodroplet isolation (HENDI) techniques, and probe this species using a combination of mass spectrometry and infrared laser Stark spectroscopy. Atkinson, R.; Arey, J., Chem. Rev. 2003, 103, 4605-4638. Mellouki, A.; Le Bras, G.; Sidebottom, H., Chem. Rev. 2003, 103, 5077-5096. Smith, I. W. M.; Ravishankara, A. R., J. Phys. Chem. A 2002, 106, 4798-4807 Shannon, R. J.; Blitz, M. A.; Goddard, A.; Heard, D. E., Nat. Chem. 2013, 5, 745-749. Martin, J. C. G.; Caravan, R. L.; Blitz, M. A.; Heard, D. E.; Plane, J. M. C., J. Phys. Chem. A 2014, 118, 2693-2701.

  2. Interventional bioethics: epistemology for peripheral countries.

    PubMed

    Garrafa, Volnei; Porto, Dora

    2008-01-01

    Principlism, which originated in the United States based on four supposedly universal principles, brought international visibility to the field of bioethics over the final years of the twentieth century. Nevertheless, from 1990 onwards, criticism regarding the universal applicability of these principles emerged, especially concerning their limitations in dealing with collective macroproblems--social, sanitary and environmental--that are seen in poor developing countries every day. In this respect, the idea of Intervention Bioethics was presented at the University of Brasília, Brazil, in 1998, and was subsequently expanded to encompass other Latin American countries. From the outset, this epistemological proposal of third-world construction and perspective advocated politicisation of the international bioethics agenda, and this aim was achieved through the content of UNESCO's Universal Declaration on Bioethics and Human Rights, which was adopted in 2005. Grounded in a utilitarian and consequentialistic approach, Intervention Bioethics gives priority, ahead of vulnerabilities relating to gender, sexual orientation, ethnicity and similar considerations, to the fields of social and sanitary justice in order to defend the poorest and most disempowered populations in the asymmetrical contemporary world. PMID:18664003

  3. Temporal occurrence of two morpho butterflies (Lepidoptera: Nymphalidae): influence of weather and food resources.

    PubMed

    Freire, Geraldo; Nascimento, André Rangel; Malinov, Ivan Konstantinov; Diniz, Ivone R

    2014-04-01

    The seasonality of fruit-feeding butterflies is very well known. However, few studies have analyzed the influence of climatic variables and resource availability on the temporal distributions of butterflies. Morpho helenor achillides (C. Felder and R. Felder 1867) and Morpho menelaus coeruleus (Perry 1810) (Nymphalidae) were used as models to investigate the influences of climatic factors and food resources on the temporal distribution of these Morphinae butterflies. These butterflies were collected weekly from January 2005 to December 2006 in the Parque Nacional de Brasília (PNB). In total, 408 individuals were collected, including 274 of M. helenor and 134 of M. menelaus. The relative abundance of the two species was similar in 2005 (n = 220) and 2006 (n = 188). Of the variables considered, only the relative humidity and resource availability measured in terms of phenology of zoochorous fruits of herbaceous plants explained a large proportion of the variation in the abundance of these butterflies. Both of the explanatory variables were positively associated with the total abundance of individuals and with the abundances of M. helenor and M. menelaus considered separately. The phenology of anemochorous fruits was negatively associated with butterfly abundance. The temporal distribution of the butterflies was better predicted by the phenology of the zoochorous fruits of herbaceous plants than by the climatic predictors.

  4. Biomedical Use of Aerospace Personal Cooling Garments

    NASA Technical Reports Server (NTRS)

    Webbon, Bruce W.; Montgomery, Leslie D.; Callaway, Robert K.

    1994-01-01

    Personal thermoregulatory systems are required during extravehicular activity (EVA) to remove the metabolic heat generated by the suited astronaut. The Extravehicular and Protective Systems (STE) Branch of NASA Ames Research Center has developed advanced concepts or liquid cooling garments for both industrial and biomedical applications for the past 25 years. Examples of this work include: (1) liquid cooled helmets for helicopter pilots and race car drivers; (2) vests for fire and mine rescue personnel; (3) bras to increase the definition of tumors during thermography; (4) lower body garments for young women with erythomelaigia; and (5) whole body garments used by patients with multiple sclerosis (MS). The benefits of the biomedical application of artificial thermoregulation received national attention through two recent events: (1) the liquid-cooled garment technology was inducted into the United States Space Foundation's Space Technology Hall of Fame (1993); and (2) NASA has signed a joint Memorandum of Understanding with the Multiple Sclerosis Association (1994) to share this technology for use with MS patient treatment. The STE Branch is currently pursuing a program to refine thermoregulatory design in light of recent technology developments that might be applicable for use by several medical patient populations. Projects have been initiated to apply thermoregulatory technology for the treatment and/or rehabilitation of patients with spinal cord injuries, multiple sclerosis, migraine headaches, and to help prevent the loss of hair during chemotherapy.

  5. Aspects of Quantum Theory

    NASA Astrophysics Data System (ADS)

    Salam, Abdus; Wigner, E. P.

    2010-03-01

    Preface; List of contributors; Bibliography of P. A. M. Dirac; 1. Dirac in Cambridge R. J. Eden and J. C. Polkinghorne; 2. Travels with Dirac in the Rockies J. H. Van Vleck; 3. 'The golden age of theoretical physics': P. A. M. Dirac's scientific work from 1924 to 1933 Jagdish Mehra; 4. Foundation of quantum field theory Res Jost; 5. The early history of the theory of electron: 1897-1947 A. Pais; 6. The Dirac equation A. S. Wightman; 7. Fermi-Dirac statistics Rudolph Peierls; 8. Indefinite metric in state space W. Heisenberg; 9. On bras and kets J. M. Jauch; 10. The Poisson bracket C. Lanczos; 11. La 'fonction' et les noyaux L. Schwartz; 12. On the Dirac magnetic poles Edoardo Amadli and Nicola Cabibbo; 13. The fundamental constants and their time variation Freeman J. Dyson; 14. On the time-energy uncertainty relation Eugene P. Wigner; 15. The path-integral quantisation of gravity Abdus Salam and J. Strathdee; Index; Plates.

  6. Are opossums a relevant factor associated with asymptomatic Leishmania infection in the outskirts of the largest Brazilian cities?

    PubMed

    Carranza-Tamayo, César Omar; Werneck, Guilherme Loureiro; Romero, Gustavo Adolfo Sierra

    2016-01-01

    A population survey was conducted to explore the prevalence and factors associated with Leishmania infection in the Fercal region of the Federal District. The Fercal region is a group of neighborhoods in Brasília in which the first cases of visceral leishmaniasis were described. Leishmania infection was established by a positive leishmanin test. Although other tests were performed in the study (an immunochromatographic assay (Kalazar detect(®)) and a molecular assay), only the leishmanin skin test provided sufficient results for the measurement of the disease prevalence. Data on the epidemiological, clinical and environmental characteristics of individuals were collected along with the diagnostic tests. After sampling and enrollment, seven hundred people from 2 to 14 years of age were included in the study. The prevalence of Leishmania infection was 33.28% (95% CI 29.87-36.84). The factors associated with Leishmania infection according to the multivariate analysis were age of more than seven years and the presence of opossums near the home. Age is a known factor associated with Leishmania infection; however, the presence of wild animals, as described, is an understudied factor. The presence of opossums, which are known reservoirs of Leishmania, in peri-urban areas could be the link between the rural and urban occurrence of visceral leishmaniasis in the outskirts of largest Brazilian cities, as suggested by previous studies.

  7. Apomixis in cassava: advances and challenges.

    PubMed

    Freitas, D Y H; Nassar, N M A

    2013-04-02

    Cassava is the most important staple crop in the Tropics and Subtropics. Apomixis may revolutionize its production due to various attributes. These potential advantages include production by true seed, maintaining cultivar superiority over generations without segregation, and avoiding contamination by bacteria and viruses. Historically, apomixis was initially observed by International Institute of Tropical Agriculture researchers, in the 1980s, in homogenous progeny of hybrid crosses. Later, from 1980 through 2010, apomixis was extensively studied by Universidade de Brasília, in order to determine contributing mechanisms and occurrence. Apomixis genes occur naturally at low frequencies in cultivated cassava and can be transferred by crosses with wild species. Apparently, apomixis in cassava is controlled by more than one recessive gene, which act in an additive form. Aneuploidy is associated with apomixis in cassava and can provide the double dosages necessary for recessive gene action. By using molecular techniques, genetic homogeneous progeny has been demonstrated, while embryonic exams have shown nucellar multiembryos. Polyploidy was found to increase apomixis percentage. From an evolutionary viewpoint, polyploidy has contributed to production of new species, when combined with apomixis. Recently, somatic embryos have been detected in the integument, revealing a rare model of apomixis that has only been documented in cassava.

  8. Clinical, hematological, biochemical, and ultrasonographic aspects of Platynosomum sp. (Trematoda: Dicrocoeliidae) infection of captive Callithrix penicillata.

    PubMed

    Mattioli, Mariana Portugal; Batista, Juliana dos Santos; Ferrari, Marlon; Paludo, Giane Regina; Dias, Cecília Azevedo; Hoppe, Estevam G L; da Rocha, Gino Chaves; Monteiro, Rafael Veríssimo

    2016-04-01

    Trematodes from the genus Platynosomum have been found to infect Neotropical primates in captivity, but little is known about their pathogeny in such hosts. This study evaluated the physiological effects of natural infection by the liver-dwelling trematode Platynosomum sp. in ten males and ten females of Callithrix penicillata kept in captivity at the Primate Center of the University of Brasília. The marmosets were examined twice, 6 months apart. The following parameters were analyzed: complete blood count, bleeding time, serum total protein, albumin, and the liver enzymes AST and ALT, and both a stool analysis and a liver ultrasonic evaluation were performed. We were able to characterize a group of abnormalities associated with this trematode infection which were mainly derived from the hepatitis caused by it: coagulation disorders, abnormal red blood cells, hypoalbuminemia, and abnormal levels of liver-linked serum enzymes. Eosinophilia and thrombocytopenia were also commonly seen. All of the aforementioned abnormalities were in good accord with typical effects of trematodes on liver parenchyma. We suggest that this set of abnormalities is characteristic of the infection of C. penicillata with Platynosomum sp., and should be among the most prominent aspects that the veterinary surgeon considers when suspecting such an infection. We also suggest that these clinical signs and abnormalities will be similar in other liver-dwelling trematode-infected primate species. PMID:26922567

  9. Grid digital elevation model based algorithms for determination of hillslope width functions through flow distance transforms

    NASA Astrophysics Data System (ADS)

    Liu, Jintao; Chen, Xi; Zhang, Xingnan; Hoagland, Kyle D.

    2012-04-01

    Recently developed hillslope storage dynamics theory can represent the essential physical behavior of a natural system by accounting explicitly for the plan shape of a hillslope in an elegant and simple way. As a result, this theory is promising for improving catchment-scale hydrologic modeling. In this study, grid digital elevation model (DEM) based algorithms for determination of hillslope geometric characteristics (e.g., hillslope units and width functions in hillslope storage dynamics models) are presented. This study further develops a method for hillslope partitioning, established by Fan and Bras (1998), by applying it on a grid network. On the basis of hillslope unit derivation, a flow distance transforms method (TD∞) is suggested in order to decrease the systematic error of grid DEM-based flow distance calculation caused by flow direction approximation to streamlines. Hillslope width transfer functions are then derived to convert the probability density functions of flow distance into hillslope width functions. These algorithms are applied and evaluated on five abstract hillslopes, and detailed tests and analyses are carried out by comparing the derivation results with theoretical width functions. The results demonstrate that the TD∞ improves estimations of the flow distance and thus hillslope width function. As the proposed procedures are further applied in a natural catchment, we find that the natural hillslope width function can be well fitted by the Gaussian function. This finding is very important for applying the newly developed hillslope storage dynamics models in a real catchment.

  10. Economical, simple method for production of the gaseous environment required for cultivation of Campylobacter jejuni.

    PubMed Central

    Pennie, R A; Zunino, J N; Rose, C E; Guerrant, R L

    1984-01-01

    Campylobacter jejuni is an enteric pathogen recognized worldwide as a cause of diarrhea. Its isolation from stool samples requires a microaerophilic environment that heretofore has been expensive and cumbersome to create. An economical, portable, and simple method is described which involves the production of appropriate concentrations of oxygen and carbon dioxide. Inside a plastic bag are placed two cups, one containing fine steel wool (grade 0) previously soaked in a 2.5% aqueous solution of copper sulfate and the other containing an Alka-Seltzer tablet in tap water. As suggested by Jurgensen et al. (Rev. Bras. Pat. Clin. 18:58-63, 1982), we used the effervescent antacid to generate CO2. By plate counts, we found this method to be as reliable in the cultivation of 20 isolates of C. jejuni in pure and mixed fecal culture as the reference gas method (85% N2, 10% CO2, and 5% O2). Analyses of the gas mixture inside the bag after up to 24 h of incubation confirmed the creation of an atmosphere of reduced O2 and increased CO2 concentrations. This method is eminently suitable for field situations in which more costly supplies are not available. PMID:6436301

  11. Economical, simple method for production of the gaseous environment required for cultivation of Campylobacter jejuni.

    PubMed

    Pennie, R A; Zunino, J N; Rose, C E; Guerrant, R L

    1984-09-01

    Campylobacter jejuni is an enteric pathogen recognized worldwide as a cause of diarrhea. Its isolation from stool samples requires a microaerophilic environment that heretofore has been expensive and cumbersome to create. An economical, portable, and simple method is described which involves the production of appropriate concentrations of oxygen and carbon dioxide. Inside a plastic bag are placed two cups, one containing fine steel wool (grade 0) previously soaked in a 2.5% aqueous solution of copper sulfate and the other containing an Alka-Seltzer tablet in tap water. As suggested by Jurgensen et al. (Rev. Bras. Pat. Clin. 18:58-63, 1982), we used the effervescent antacid to generate CO2. By plate counts, we found this method to be as reliable in the cultivation of 20 isolates of C. jejuni in pure and mixed fecal culture as the reference gas method (85% N2, 10% CO2, and 5% O2). Analyses of the gas mixture inside the bag after up to 24 h of incubation confirmed the creation of an atmosphere of reduced O2 and increased CO2 concentrations. This method is eminently suitable for field situations in which more costly supplies are not available. PMID:6436301

  12. The movement of the trunk and breast during front crawl and breaststroke swimming.

    PubMed

    Mills, Chris; Lomax, Mitch; Ayres, Bessie; Scurr, Joanna

    2015-01-01

    Breast displacement has been investigated in various activities to inform bra design, with the goal of minimising movement; however, breast motion during swimming has yet to be considered. The aim was to investigate trunk and breast kinematics whilst wearing varying levels of breast support during two swimming strokes. Six larger-breasted females swam front crawl and breaststroke (in a swimming flume), in three breast support conditions while three video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated. Greater breast displacement occurred mediolaterally in the swimsuit condition (7.8, s = 1.5 cm) during front crawl and superioinferiorly in the bare-breasted condition (3.7, s = 1.6 cm) during breaststroke, with the sports bra significantly reducing breast displacements. During front crawl, the greatest trunk roll occurred in the sports bra condition (43.1, s = 8.3°) and during breaststroke greater trunk extension occurred in the swimsuit condition (55.4, s = 5.0°); however, no differences were found in trunk kinematics between the three breast support conditions. Results suggest that the swimsuit was ineffective as a means of additional support for larger-breasted women during swimming; incorporating design features of sports bras into swimsuits may improve the breast support provided.

  13. Breast Support Garments are Ineffective at Reducing Breast Motion During an Aqua Aerobics Jumping Exercise

    PubMed Central

    Mills, Chris; Ayres, Bessie; Scurr, Joanna

    2015-01-01

    The buoyant forces of water during aquatic exercise may provide a form of ‘natural’ breast support and help to minimise breast motion and alleviate exercise induced breast pain. Six larger-breasted females performed standing vertical land and water-based jumps, whilst wearing three breast support conditions. Underwater video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated as well as exercised induced breast pain scores. Key results showed that the swimsuit and sports bra were able to significantly reduce the superioinferior breast range of motion by 0.04 and 0.05 m, respectively, and peak velocity by 0.23 and 0.33 m/s, respectively, during land-based jumping when compared to the bare-breasted condition, but were ineffective at reducing breast kinematics during water-based jumping. Furthermore, the magnitude of the swimsuit superioinferior breast range of motion during water-based jumping was significantly greater than land-based jumping (0.13 m and 0.06 m), yet there were no significant differences in exercise induced breast pain, thus contradicting previously published relationships between these parameters on land. Furthermore, the addition of an external breast support garment was able to reduce breast kinematics on land but not in water, suggesting the swimsuit and sports bras were ineffective and improvements in swimwear breast support garments may help to reduce excessive breast motion during aqua aerobic jumping exercises. PMID:26240648

  14. Breast Support Garments are Ineffective at Reducing Breast Motion During an Aqua Aerobics Jumping Exercise.

    PubMed

    Mills, Chris; Ayres, Bessie; Scurr, Joanna

    2015-06-27

    The buoyant forces of water during aquatic exercise may provide a form of 'natural' breast support and help to minimise breast motion and alleviate exercise induced breast pain. Six larger-breasted females performed standing vertical land and water-based jumps, whilst wearing three breast support conditions. Underwater video cameras recorded the motion of the trunk and right breast. Trunk and relative breast kinematics were calculated as well as exercised induced breast pain scores. Key results showed that the swimsuit and sports bra were able to significantly reduce the superioinferior breast range of motion by 0.04 and 0.05 m, respectively, and peak velocity by 0.23 and 0.33 m/s, respectively, during land-based jumping when compared to the bare-breasted condition, but were ineffective at reducing breast kinematics during water-based jumping. Furthermore, the magnitude of the swimsuit superioinferior breast range of motion during water-based jumping was significantly greater than land-based jumping (0.13 m and 0.06 m), yet there were no significant differences in exercise induced breast pain, thus contradicting previously published relationships between these parameters on land. Furthermore, the addition of an external breast support garment was able to reduce breast kinematics on land but not in water, suggesting the swimsuit and sports bras were ineffective and improvements in swimwear breast support garments may help to reduce excessive breast motion during aqua aerobic jumping exercises.

  15. Biochemical View: A Web Site Providing Material for Teaching Biochemistry Using Multiple Approaches

    NASA Astrophysics Data System (ADS)

    Dórea, Fernanda C.; Rodrigues, Higor S.; Lapouble, Oscar M. M.; Pereira, Márcio R.; Castro, Mariana S.; Fontes, Wagner

    2007-11-01

    Computational resources are valuable tools for teaching biochemistry. Often, however, the necessary information is dispersed throughout several Web sites and many of the biochemistry software programs are only available commercially. Considering the difficulties of understanding abstract biochemical concepts, a Web site, Biochemical View (accessed Aug 2007) has been developed at the University of Brasília (UnB), Brazil. Its main goals are to complement course instruction and materials already in use, provide material to teachers preparing conventional and online courses, and—because free, full access is allowed—popularize the use of these resources in undergraduate courses. The contents, which include the usual metabolic pathways explaining the metabolism of carbohydrates, amino acids, lipids, and nucleic acids, are presented in two and three-dimensional formats, complemented with objective texts, schematics, and a description of regulation points. In this work, a new approach to metabolic pathways is employed, namely metabolic participation diagrams. In addition, experimental protocols for laboratory classes, study material, and detailed information about each molecule taking part in a specific metabolic pathway have been also made available in the Web site. The process of constructing the site is described and the results of students using this Web site are evaluated based on exam scores and survey forms, which show a significant improvement in students' success in learning biochemistry.

  16. On the Use of Dance as a Rehabilitation Approach for Children with Cerebral Palsy: A Single Case Study.

    PubMed

    Morán Pascual, Patricia; Mortes Roselló, Esther; Domingo Jacinto, Amparo; Belda Lois, Juan Manuel; Bermejo, Ignacio; Medina, Enric; Barberà Guillem, Ricard

    2015-01-01

    Cerebral Palsy (CP) is the most common motor disability in childhood. It is a group of permanent disorders that affect child development causing disorders of movement and posture and activity limitations. The impairment of psychomotor skills of children with Cerebral Palsy is attributed to a permanent alteration occurred in non-progressive brain development of the fetus or nursing infant. Some motor related symptoms can be treated using proper physical therapy. However, one of the biggest problems of the usual physical therapy is adherence to therapy. Ballet can be an alternative or a complement to physiotherapy, with the added attraction of not being part of a to therapy, but a fun activity with the extra reward associated with the realization of an artistic activity. For some years the ballet is used as therapeutically valuable for both children with cerebral palsy: Intensive ballet training can generate changes in the sensorimotor cortex. Ballet is characterized by a complex process of movements that have to be in a musical rhythm (hence have to be precise), in which there is an overall coordination of the muscles. It is also a highly motivating and rewarding activity that allows many children with CP sharing the activities of their peers without special needs. Objective measurements of the Full Port de Bras movement has been chosen as an index of improvement. The results shows progressive improvements of the execution in a single case.

  17. Contribution of the Unified Health Care System to mammography screening in Brazil, 2013*

    PubMed Central

    Freitas-Junior, Ruffo; Rodrigues, Danielle Cristina Netto; Corrêa, Rosangela da Silveira; Peixoto, João Emílio; de Oliveira, Humberto Vinícius Carrijo Guimarães; Rahal, Rosemar Macedo Sousa

    2016-01-01

    Objective To estimate the coverage of opportunistic mammography screening performed via the Brazilian Sistema Único de Saúde (SUS, Unified Health Care System), at the state and regional level, in 2013. Materials and Methods This was an ecological study in which coverage was estimated by determining the ratio between the number of mammograms performed and the expected number of mammograms among the population of females between 50 and 69 years of age. The number of mammograms performed in the target population was obtained from the Outpatient Database of the Information Technology Department of the SUS. To calculate the expected number of mammograms, we considered 58.9% of the target population, the proportion that would be expected on the basis of the recommendations of the Brazilian National Cancer Institute. Results In 2013, the estimated national coverage of mammography screening via the SUS was 24.8%. The mammography rate ranged from 12.0% in the northern region to 31.3% in the southern region. When stratified by state, coverage was lowest in the state of Pará and highest in the state of Santa Catarina (7.5% and 35.7%, respectively). Conclusion The coverage of mammography screening performed via the SUS is low. There is a significant disparity among the Brazilian states (including the Federal District of Brasília) and among regions, being higher in the south/southeast and lower in the north/northeast.

  18. On the Use of Dance as a Rehabilitation Approach for Children with Cerebral Palsy: A Single Case Study.

    PubMed

    Morán Pascual, Patricia; Mortes Roselló, Esther; Domingo Jacinto, Amparo; Belda Lois, Juan Manuel; Bermejo, Ignacio; Medina, Enric; Barberà Guillem, Ricard

    2015-01-01

    Cerebral Palsy (CP) is the most common motor disability in childhood. It is a group of permanent disorders that affect child development causing disorders of movement and posture and activity limitations. The impairment of psychomotor skills of children with Cerebral Palsy is attributed to a permanent alteration occurred in non-progressive brain development of the fetus or nursing infant. Some motor related symptoms can be treated using proper physical therapy. However, one of the biggest problems of the usual physical therapy is adherence to therapy. Ballet can be an alternative or a complement to physiotherapy, with the added attraction of not being part of a to therapy, but a fun activity with the extra reward associated with the realization of an artistic activity. For some years the ballet is used as therapeutically valuable for both children with cerebral palsy: Intensive ballet training can generate changes in the sensorimotor cortex. Ballet is characterized by a complex process of movements that have to be in a musical rhythm (hence have to be precise), in which there is an overall coordination of the muscles. It is also a highly motivating and rewarding activity that allows many children with CP sharing the activities of their peers without special needs. Objective measurements of the Full Port de Bras movement has been chosen as an index of improvement. The results shows progressive improvements of the execution in a single case. PMID:26294586

  19. Use of psychotropic medications by caregivers of elderly patients with dementia: is this a sign of caregiver burden?

    PubMed

    Camargos, Einstein Francisco; Souza, Andrea Brígida; Nascimento, Aline Silva; Morais-E-Silva, Alessandra Cicari; Quintas, Juliana Lima; Louzada, Luciana Lilian; Medeiros-Souza, Patricia

    2012-03-01

    This study evaluated the consumption of psychotropic medications by caregivers of elderly patients with or without dementia. This was a cross-sectional study conducted at all geriatric units in Brasília, Brazil, during a two-month period. Structured interviews were performed with 311 caregivers of people with or without dementia and they completed questionnaires. Among the caregivers, 196 (63%) were caregivers of patients with dementia and 115 (37%) were caregivers of patients without dementia. Forty-four caregivers (14.1%) were taking psychotropic drugs (benzodiazepines or antidepressants), and this usage was more frequent among caregivers of patients with dementia (p<0.01). Twenty-two caregivers of patients with dementia (11.4%) had used sleeping pills after beginning care, compared with only five (4.3%) caregivers of patients without dementia (p<0.01). In conclusion, this study found that caregivers of patients with dementia took psychotropic drugs (benzodiazepines and antidepressants) more frequently than the ones of patients without dementia. PMID:22392108

  20. Particle-in-cell simulations of Hall plasma thrusters

    NASA Astrophysics Data System (ADS)

    Miranda, Rodrigo; Ferreira, Jose Leonardo; Martins, Alexandre

    2016-07-01

    Hall plasma thrusters can be modelled using particle-in-cell (PIC) simulations. In these simulations, the plasma is described by a set of equations which represent a coupled system of charged particles and electromagnetic fields. The fields are computed using a spatial grid (i.e., a discretization in space), whereas the particles can move continuously in space. Briefly, the particle and fields dynamics are computed as follows. First, forces due to electric and magnetic fields are employed to calculate the velocities and positions of particles. Next, the velocities and positions of particles are used to compute the charge and current densities at discrete positions in space. Finally, these densities are used to solve the electromagnetic field equations in the grid, which are interpolated at the position of the particles to obtain the acting forces, and restart this cycle. We will present numerical simulations using software for PIC simulations to study turbulence, wave and instabilities that arise in Hall plasma thrusters. We have sucessfully reproduced a numerical simulation of a SPT-100 Hall thruster using a two-dimensional (2D) model. In addition, we are developing a 2D model of a cylindrical Hall thruster. The results of these simulations will contribute to improve the performance of plasma thrusters to be used in Cubesats satellites currenty in development at the Plasma Laboratory at University of Brasília.

  1. A covalent adduct of MbtN, an acyl-ACP dehydrogenase from Mycobacterium tuberculosis, reveals an unusual acyl-binding pocket.

    PubMed

    Chai, Ai-Fen; Bulloch, Esther M M; Evans, Genevieve L; Lott, J Shaun; Baker, Edward N; Johnston, Jodie M

    2015-04-01

    Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis. Access to iron in host macrophages depends on iron-chelating siderophores called mycobactins and is strongly correlated with Mtb virulence. Here, the crystal structure of an Mtb enzyme involved in mycobactin biosynthesis, MbtN, in complex with its FAD cofactor is presented at 2.30 Å resolution. The polypeptide fold of MbtN conforms to that of the acyl-CoA dehydrogenase (ACAD) family, consistent with its predicted role of introducing a double bond into the acyl chain of mycobactin. Structural comparisons and the presence of an acyl carrier protein, MbtL, in the same gene locus suggest that MbtN acts on an acyl-(acyl carrier protein) rather than an acyl-CoA. A notable feature of the crystal structure is the tubular density projecting from N(5) of FAD. This was interpreted as a covalently bound polyethylene glycol (PEG) fragment and resides in a hydrophobic pocket where the substrate acyl group is likely to bind. The pocket could accommodate an acyl chain of 14-21 C atoms, consistent with the expected length of the mycobactin acyl chain. Supporting this, steady-state kinetics show that MbtN has ACAD activity, preferring acyl chains of at least 16 C atoms. The acyl-binding pocket adopts a different orientation (relative to the FAD) to other structurally characterized ACADs. This difference may be correlated with the apparent ability of MbtN to catalyse the formation of an unusual cis double bond in the mycobactin acyl chain.

  2. From gene expressions to genetic networks

    NASA Astrophysics Data System (ADS)

    Cieplak, Marek

    2009-03-01

    A method based on the principle of entropy maximization is used to identify the gene interaction network with the highest probability of giving rise to experimentally observed transcript profiles [1]. In its simplest form, the method yields the pairwise gene interaction network, but it can also be extended to deduce higher order correlations. Analysis of microarray data from genes in Saccharomyces cerevisiae chemostat cultures exhibiting energy metabollic oscillations identifies a gene interaction network that reflects the intracellular communication pathways. These pathways adjust cellular metabolic activity and cell division to the limiting nutrient conditions that trigger metabolic oscillations. The success of the present approach in extracting meaningful genetic connections suggests that the maximum entropy principle is a useful concept for understanding living systems, as it is for other complex, nonequilibrium systems. The time-dependent behavior of the genetic network is found to involve only a few fundamental modes [2,3]. [4pt] REFERENCES:[0pt] [1] T. R. Lezon, J. R. Banavar, M. Cieplak, A. Maritan, and N. Fedoroff, Using the principle of entropy maximization to infer genetic interaction networks from gene expression patterns, Proc. Natl. Acad. Sci. (USA) 103, 19033-19038 (2006) [0pt] [2] N. S. Holter, M. Mitra, A. Maritan, M. Cieplak, J. R. Banavar, and N. V. Fedoroff, Fundamental patterns underlying gene expression profiles: simplicity from complexity, Proc. Natl. Acad. Sci. USA 97, 8409-8414 (2000) [0pt] [3] N. S. Holter, A. Maritan, M. Cieplak, N. V. Fedoroff, and J. R. Banavar, Dynamic modeling of gene expression data, Proc. Natl. Acad. Sci. USA 98, 1693-1698 (2001)

  3. [Spontaneous dissection of the anterior cerebral artery that simultaneously presented with cerebral infarction and subarachnoid hemorrhage, successfully treated with conservative management: a case report].

    PubMed

    Nanbara, Sho; Tsutsumi, Keisuke; Takahata, Hideaki; Fujimoto, Takashi; Kawahara, Ichiro; Ono, Tomonori; Toda, Keisuke; Baba, Hiroshi; Yonekura, Masahiro

    2012-07-01

    We recently encountered a rare case of anterior cerebral artery dissection (ACAD) that accompanied fresh cerebral infarction (CI) and subarachnoid hemorrhage (SAH). An initial head CT showed a thin SAH in the interhemispheric cistern and cortical sulcus of the left frontal surface. Subsequent MRI performed 10 min after head CT scan revealed a fresh infarction in the left ACA region. MR-and digital subtraction angiograms demonstrated a dissection in the A2 portion of the left ACA with a leak of contrast media around the left A3 portion, suggesting that the bleeding occurred in a distal portion of the main dilation. Without anti-thrombotic therapy, the patient recovered without complications by blood pressure control and administration of brain-function protection therapies. We found 11 cases similar to the present case in the literature. All cases presented with lower-extremity dominant hemiparesis; however, sudden onset headache was rare. Blood pressure was not well-controlled in 4 out of the 6 known hypertensive cases. Main sites of dissection were located at the A2 portion in all cases except one A3 lesion, and extended to A3 in 2 cases. Conservative therapy led to favorable outcome in 8 cases, while 4 cases underwent surgical interventions for increasing risk of aneurysm rupture after initial observational therapies. Re-bleeding did not occur in any of the 12 cases reviewed. These data suggest that conservative treatment can be considered for an initial management of ACAD with simultaneous CI and SAH. More evidence needs to be accumulated to establish the optimal therapeutic approach for ACAD associated with CI and SAH.

  4. VizieR Online Data Catalog: HII regions of the Northern Milky Way (Dubout-Crillon+ 1976)

    NASA Astrophysics Data System (ADS)

    Dubout-Crillon, R.

    2011-04-01

    The photographs were made at the Observatoire de Haute-Provence at the end of 1969, throughout 1970, and then again in 1972. A 5cm refractor was used with a very selective interference filter (Δλ=10Å) centered on Hα, and a focal reducer took the f/5 beam down to f/1.25. Exposures were made using flashed 103-aE plates. The catalogue includes also the HII regions discovered by Sivan 1974 (Compt. Rend. Acad. Sci. Paris 278, 127; 1974A&AS...16..163S). (1 data file).

  5. Default taxonomy: Ernst Mayr's view of the microbial world

    NASA Technical Reports Server (NTRS)

    Woese, C. R.

    1998-01-01

    This perspective is a response to a taxonomic proposal by E. Mayr ["Two empires or three?" (1998) Proc. Natl. Acad. Sci. USA 95, 9720-9723]. Mayr has suggested that the now accepted classification of life into three primary domains, Archaea, Bacteria, and Eucarya-originally proposed by myself and others--be abandoned in favor of the earlier Prokaryote-Eukaryote classification. Although the matter appears a taxonomic quibble, it is not that simple. At issue here are differing views as to the nature of biological classification, which are underlain by differing views as to what biology is and will be--matters of concern to all biologists.

  6. Etienne-François Geoffroy (1672-1731), a Chemist on the Frontiers.

    PubMed

    Joly, Bernard

    2014-01-01

    Etienne-François Geoffroy is certainly the most representative chemist of the Paris Académie Royale des Sciences in the early eighteenth century. Interested in Newtonian ideas, he did not reject Cartesian mechanism. He is the inventor of the "Table des rapports entre les substances chimiques," which remained in use throughout the eighteenth century, but he drew from the alchemical tradition. He readily theorized about the composition of metals or the laws of chemical affinities, but he practiced a chemistry that was rooted in laboratory work and the search for substances useful to craftsmen. PMID:26103751

  7. Etienne-François Geoffroy (1672-1731), a Chemist on the Frontiers.

    PubMed

    Joly, Bernard

    2014-01-01

    Etienne-François Geoffroy is certainly the most representative chemist of the Paris Académie Royale des Sciences in the early eighteenth century. Interested in Newtonian ideas, he did not reject Cartesian mechanism. He is the inventor of the "Table des rapports entre les substances chimiques," which remained in use throughout the eighteenth century, but he drew from the alchemical tradition. He readily theorized about the composition of metals or the laws of chemical affinities, but he practiced a chemistry that was rooted in laboratory work and the search for substances useful to craftsmen.

  8. Design of molecular control mechanisms and the demand for gene expression.

    PubMed Central

    Savageau, M A

    1977-01-01

    Regulation by a repressor protein is the mechanism selected when, in the organism's natural environment, there is low demand for expression of the regulated structural genes. Regulation by an activator protein is selected when there is high demand for expression of the regulated structural genes. These general conclusions are useful in relating physiological function to underlying molecular determinants in a wide variety of systems that includes repressible biosynthetic pathways, inducible biosynthetic enzymes, inducible drug resistance, and prophage induction, as well as inducible catabolic pathways, for which a special case of this prediction previously was reported [Savageau, M. A. (1974) Proc. Natl. Acad. Sci. USA 71, 2453-2455]. PMID:271992

  9. The road to understanding an ion pump

    NASA Astrophysics Data System (ADS)

    Toyoshima, Chikashi

    2016-04-01

    In the past 25 years or so I have been working almost exclusively on two proteins: the Ca2+-ATPase of muscle sarcoplasmic reticulum, and the Na+, K+-ATPase expressed in all animal cells, both are membrane ion pumps representing P-type ion translocating ATPases. My ambition as a scientist is to completely understand the meaning of their atomic structures. How I became a scientist is described elsewhere (Nuzzo R 2006 Proc. Natl. Acad. Sci. USA 103 1165-7), and focus here is given to my struggle towards a deep understanding of Ca2+-ATPase. This is a long but very fascinating and rewarding journey.

  10. Crystal Structures of Nitroalkane Oxidase: Insights into the Reaction Mechanism of a Covalent Complex of the Flavoenzyme Trapped During Turnover

    SciTech Connect

    Nagpal,A.; Valley, M.; Fitzpatrick, P.; Orville, A.

    2006-01-01

    Nitroalkane oxidase (NAO) from Fusarium oxysporum catalyzes the oxidation of neutral nitroalkanes to the corresponding aldehydes or ketones with the production of H2O2 and nitrite. The flavoenzyme is a new member of the acyl-CoA dehydrogenase (ACAD) family, but it does not react with acyl-CoA substrates. We present the 2.2 Angstroms resolution crystal structure of NAO trapped during the turnover of nitroethane as a covalent N5-FAD adduct (ES*). The homotetrameric structure of ES* was solved by MAD phasing with 52 Se-Met sites in an orthorhombic space group. The electron density for the N5-(2-nitrobutyl)-1,5-dihydro-FAD covalent intermediate is clearly resolved. The structure of ES* was used to solve the crystal structure of oxidized NAO at 2.07 Angstroms resolution. The c axis for the trigonal space group of oxidized NAO is 485 Angstroms, and there are six subunits (11/2 holoenzymes) in the asymmetric unit. Four of the active sites contain spermine (EI), a weak competitive inhibitor, and two do not contain spermine (E{sup ox}). The active-site structures of E{sup ox}, EI, and ES* reveal a hydrophobic channel that extends from the exterior of the protein and terminates at Asp402 and the N5 position on the re face of the FAD. Thus, Asp402 is in the correct position to serve as the active-site base, where it is proposed to abstract the {alpha} proton from neutral nitroalkane substrates. The structures for NAO and various members of the ACAD family overlay with root-mean-square deviations between 1.7 and 3.1 Angstroms. The homologous region typically spans more than 325 residues and includes Glu376, which is the active-site base in the prototypical member of the ACAD family. However, NAO and the ACADs exhibit differences in hydrogen-bonding patterns between the respective active-site base, substrate molecules, and FAD. These likely differentiate NAO from the homologues and, consequently, are proposed to result in the unique reaction mechanism of NAO.

  11. What does the arrest and release of Emile Borel and his colleagues in 1941 tell us about the German occupation of France?

    PubMed

    Mazliak, Laurent; Shafer, Glenn

    2011-12-01

    The Germans occupying Paris arrested Emile Borel and three other members of the Académie des Sciences in October 1941 and released them about five weeks later. Drawing on German and French archives and other sources, we argue that these events illustrate the complexity of the motivations and tactics of the occupiers and the occupied. While Borel and his colleagues were genuine members of the Resistance, and those who arrested them were full participants in a brutal occupation, both sides respected a bargain, of no small importance to the Vichy regime, that allowed the university to pursue its work if its members avoided overt acts of opposition.

  12. Amélioration de méthodes de modification structurale par utilisation de techniques d'expansion et de réduction d'interface: applications

    NASA Astrophysics Data System (ADS)

    Corus, M.; Balmès, E.; Billet, L.

    2002-12-01

    Une méthode proposant d'estimer de l'effet de modifications structurales distribuées est proposée ici. Une évolution des formulations classiques permettant de prendre en compte la non coïncidence des points de mesure et des points de couplage est présentée. La mise en œuvre de la méthodologie à un exemple académique et un cas d'application industriel permet de mettre en lumière les avantages de la méthodologie exposée.

  13. Identifying the occurrence time of mainshocks by means of Natural Time Analysis

    NASA Astrophysics Data System (ADS)

    Sarlis, Nicholas V.; Skordas, Efthimios S.; Lazaridou, Mary S.; Varotsos, Panayiotis A.

    2016-04-01

    By employing the new view of time, termed natural time [1], recent advances on the natural time analysis of a seismic catalogue [2] include: First, the fluctuations of the order parameter κ1 of seismicity exhibit a minimum almost simultaneous with the initiation of a Seismic Electric Signals (SES) activity [3,4]. This opens the window of a deeper understanding of the critical nature of preseismic process [5]. Second, a spatiotemporal study of the fluctuations of the order parameter of seismicity leads to an estimate of the epicentral area of a major impending mainshock [6]. Third, by starting the natural time analysis of the seismicity in the candidate epicentral area at the initiation time of the SES activity, we find that the κ1 values converge to the critical value [7-9] κ_1=0.070 a few days to one week before a mainshock. Recent applications of this procedure are presented for mainshocks that occurred close to Athens [10] during the last few years. References [1] P. A. Varotsos, N. V. Sarlis and E. S. Skordas, Phys. Rev. E {66} (2002) 011902; Practica of Athens Academy {76} (2001) 294. [2] P.A.Varotsos, N.V. Sarlis, H.K. Tanaka and E.S. Skordas, Phys. Rev. E {72} (2005) 041103. [3] P. Varotsos and M. Lazaridou, Tectonophysics {188} (1991) 321. [4] P. A. Varotsos, N. V. Sarlis, E. S. Skordas, and M. S. Lazaridou, Tectonophysics {589} (2013) 116. [5] P. Varotsos, K. Alexopoulos and M. Lazaridou, Tectonophysics {224} (1993) 1. [6] N.V. Sarlis, E.S. Skordas, P.A. Varotsos, T. Nagao, M. Kamogawa, and S. Uyeda Proc Natl Acad Sci USA {112} (2015) 986. [7] P. Varotsos, N.V. Sarlis, E.S. Skordas, S. Uyeda, and M. Kamogawa, Proc Natl Acad Sci USA {108} (2011) 11361. [8] N.V. Sarlis, E.S. Skordas, P.A. Varotsos, T. Nagao, M. Kamogawa, H. Tanaka and S. Uyeda Proc Natl Acad Sci USA {110} (2013) 13734. [9] N.V. Sarlis, E.S. Skordas, M.S. Lazaridou, and P.A. Varotsos, Proc Japan Acad Ser. ? {84} (2008) 331. [10] P.A. Varotsos, N.V. Sarlis, E.S. Skordas, S.-R. G

  14. [Boulduc's dynasty, apothecaries in Paris in XVIIth an XVIIIth centuries (following the article published in Revue d'histoire de la pharmacie, 2001, no. 331, p. 339-354)].

    PubMed

    Warolin, Christian

    2002-01-01

    Like his father Simon Boulduc, Gilles-François Boulduc worked as a demonstrator in chemistry at the Jardin Royal. He was the apothecary of King Louis XIV and King Louis XV, a member of the Académie Royale des Sciences. In addition he was appointed alderman of the town of Paris. He worked in Paris rue des Boucheries and went into partnership with another apothecary, Claude Pia. He was also the drug supplier of the Duke de Saint-Simon who quoted him several times as a Royal apothecary in his Mémoires. Gilles-François Boulduc's main chemistry research work is presented in this article.

  15. Central limit theorems and suppression of anomalous diffusion for systems with symmetry

    NASA Astrophysics Data System (ADS)

    Gottwald, Georg A.; Melbourne, Ian

    2016-10-01

    We give general conditions for the central limit theorem and weak convergence to Brownian motion (the weak invariance principle/functional central limit theorem) to hold for observables of compact group extensions of nonuniformly expanding maps. In particular, our results include situations where the central limit theorem would fail, and anomalous behaviour would prevail, if the compact group were not present. This has important consequences for systems with noncompact Euclidean symmetry and provides the rigorous proof for a conjecture made in our paper: a Huygens principle for diffusion and anomalous diffusion in spatially extended systems. Gottwald and Melbourne (2013 Proc. Natl Acad. Sci. USA 110 8411-6).

  16. Association of phorbol ester-induced hyperphosphorylation and reversible regulation of transferrin membrane receptors in HL60 cells.

    PubMed Central

    May, W S; Jacobs, S; Cuatrecasas, P

    1984-01-01

    Phorbol diesters are tumor-promoting agents that cause differentiation of HL60 human leukemic cells and concomitantly alter surface transferrin-receptor expression [Rovera, G., Ferreo, D., Pagliardi, G. L., Vartikar, J., Pessano, S., Bottero, L., Abraham, S. & Lebman, D. (1982) Ann. N.Y. Acad. Sci. 397, 211-220]. Transferrin-receptor regulation is shown here to result from a rapid and reversible internalization process that is temporally associated with reversible increased phosphorylation (hyperphosphorylation) of the transferrin receptor. Such a reversible mechanism involving regulation of these surface proteins could result in the rapid generation of an early signal for HL60 cellular differentiation. Images PMID:6326098

  17. Stabilization of Isolated Photosystem II Reaction Center Complex in the Dark and in the Light Using Polyethylene Glycol and an Oxygen-Scrubbing System 1

    PubMed Central

    McTavish, Hugh; Picorel, Rafael; Seibert, Michael

    1989-01-01

    The photosystem II reaction center as isolated (O Nanba, K Satoh [1987] Proc Natl Acad Sci USA 84: 109-112) is quite dilute and very unstable. Precipitating the complex with polyethylene glycol and resuspending it in buffer without detergent concentrates the reaction center and greatly improves its stability at 4°C in the dark as judged by light-induced electron transport activity. Furthermore, a procedure was developed to minimize photodestruction of polyethylene-glycol-concentrated material at room temperature in the light. The ability to stabilize the photosystem II reaction center should facilitate future photophysical, biochemical, and structural studies of the complex. Images Figure 1 PMID:16666564

  18. On Rank One Convex Functions that are Homogeneous of Degree One

    NASA Astrophysics Data System (ADS)

    Kirchheim, Bernd; Kristensen, Jan

    2016-07-01

    We show that positively 1-homogeneous rank one convex functions are convex at 0 and at matrices of rank one. The result is a special case of an abstract convexity result that we establish for positively 1-homogeneous directionally convex functions defined on an open convex cone in a finite dimensional vector space. From these results we derive a number of consequences including various generalizations of the Ornstein L1 non inequalities. Most of the results were announced in ( C R Acad Sci Paris Ser I 349:407-409, 2011).

  19. Nanoscale hydrodynamics in the cell: balancing motorized transport with diffusion

    PubMed Central

    Austin, Robert H.

    2008-01-01

    One of the central problems in the cell is how to transport molecules around the cell to desired locations. Since low Reynolds number conditions apply and diffusional times are large, without the aid of molecular motors to transport the fluid quickly cells could not survive, yet diffusion is still essential for the ultimate delivery of the goods. This paradox of low Reynolds number∕large Peclet number has been solved by the algal weed Chara corallina in ingenious ways, as the recent paper by Goldstein, et al. [Proc. Natl. Acad. Sci. 105, 3663–3667 (2008)] discusses at a deep but accessible way using modern hydrodynamic modeling. PMID:19404437

  20. A simplified method for extracting androgens from avian egg yolks

    USGS Publications Warehouse

    Kozlowski, C.P.; Bauman, J.E.; Hahn, D.C.

    2009-01-01

    Female birds deposit significant amounts of steroid hormones into the yolks of their eggs. Studies have demonstrated that these hormones, particularly androgens, affect nestling growth and development. In order to measure androgen concentrations in avian egg yolks, most authors follow the extraction methods outlined by Schwabl (1993. Proc. Nat. Acad. Sci. USA 90:11446-11450). We describe a simplified method for extracting androgens from avian egg yolks. Our method, which has been validated through recovery and linearity experiments, consists of a single ethanol precipitation that produces substantially higher recoveries than those reported by Schwabl.

  1. Fractional Hamiltonian monodromy from a Gauss-Manin monodromy

    SciTech Connect

    Sugny, D.; Jauslin, H. R.; Mardesic, P.; Pelletier, M.; Jebrane, A.

    2008-04-15

    Fractional Hamiltonian monodromy is a generalization of the notion of Hamiltonian monodromy, recently introduced by [Nekhoroshev, Sadovskii, and Zhilinskii, C. R. Acad. Sci. Paris, Ser. 1 335, 985 (2002); and Ann. Henri Poincare 7, 1099 (2006)] for energy-momentum maps whose image has a particular type of nonisolated singularities. In this paper, we analyze the notion of fractional Hamiltonian monodromy in terms of the Gauss-Manin monodromy of a Riemann surface constructed from the energy-momentum map and associated with a loop in complex space which bypasses the line of singularities. We also prove some propositions on fractional Hamiltonian monodromy for 1:-n and m:-n resonant systems.

  2. Bulk glassy and nonequilibrium crystalline alloys by stabilization of supercooled liquid: fabrication, functional properties and applications (Part 2)

    NASA Astrophysics Data System (ADS)

    Inoue, A.

    The novel stabilization phenomenon of supercooled liquid in special multi-component metallic alloys that follow the three component rules has enabled us to fabricate a number of bulk glassy and nonequilibrium crystalline alloys exhibiting useful characteristics. Following the previous review (Part 1; Proc. Jpn. Acad. Ser. B 81, 156-171), this paper (Part 2) reviews our recent results on the physical, chemical, mechanical and magnetic properties of the resulting bulk nonequilibrium materials including glassy single phase alloys, nanocrystal-, nanoquasicrystal- and dendritic crystal-dispersed glassy alloys and nanocrystalline alloys. Finally, the application potential of bulk glassy alloys is addressed, taking account of their novel engineering properties and production processes.

  3. Tendências de teses e dissertações sobre ensino de astronomia no Brasil

    NASA Astrophysics Data System (ADS)

    Bretones, P. S.; Megid Neto, J.

    2003-08-01

    Neste trabalho são apresentados os resultados de uma pesquisa do tipo estado da arte sobre teses e dissertações defendidas no Brasil e relativas ao ensino de Astronomia. Teve por objetivo identificar essa produção e conhecer as principais tendências da pesquisa nesse campo. O procedimento inicial consistiu de um levantamento bibliográfico junto ao Centro de Documentação em Ensino de Ciências (CEDOC) da Faculdade de Educação da UNICAMP e ao Banco de Teses da CAPES disponível na Internet. Foram localizadas 13 dissertações de mestrado e 3 teses de doutorado, as quais foram estudadas em função dos seguintes aspectos: instituição, ano de defesa, nível escolar abrangido no estudo, foco temático do estudo e gênero de trabalho acadêmico. Deste conjunto de pesquisas, 13 (81,3%) delas foram defendidas a partir da segunda metade dos anos 90, indicando uma preocupação mais recente com temas relativos ao ensino de Astronomia no conjunto da produção acadêmica em programas de pós-graduação no Brasil. Verificou-se que 43,7% dos trabalhos foram produzidas na USP e 18,8% na UNICAMP. Quanto ao nível escolar abrangido nos estudos, predominaram os estudos direcionados ao Ensino Fundamental de 5a a 8a séries (62,5%). No que diz respeito ao foco temático das pesquisas, as principais tendências voltaram-se: 56,3% para Conteúdo e Método; 43,8% para Concepções do Professor; 37,5% para Currículo e Programas; 37,5% para Recursos Didáticos. Quanto ao gênero de trabalho acadêmico, verificou-se que 43,8% são de Pesquisa Experimental e 31,3% de Pesquisa de Análise de Conteúdo. Estudos de revisão bibliográfica como este visam colaborar com a divulgação ampla da produção acadêmica em determinada área, traçando algumas de suas tendências. Ao mesmo tempo possibilita, a partir de investigações decorrentes, apontar as suas contribuições para o ensino e sinalizar com necessidades a serem supridas por futuras pesquisas.

  4. The nucleotide sequence at the termini of adenovirus type 5 DNA.

    PubMed Central

    Steenbergh, P H; Maat, J; van Ormondt, H; Sussenbach, J S

    1977-01-01

    The sequences of the first 194 base pairs at both termini of adenovirus type 5 (Ad5) DNA have been determined, using the chemical degradation technique developed by Maxam and Gilbert (Proc. Nat. Acad. Sci. USA 74 (1977), pp. 560-564). The nucleotide sequences 1-75 were confirmed by analysis of labeled RNA transcribed from the terminal HhaI fragments in vitro. The sequence data show that Ad5 DNA has a perfect inverted terminal repetition of 103 base pairs long. Images PMID:600799

  5. The protein translocation machinery of the endoplasmic reticulum.

    PubMed

    Walter, P; Gilmore, R; Müller, M; Blobel, G

    1982-12-24

    The rough endoplasmic reticulum (r.e.r.) has been postulated to possess a single translation-coupled translocation system (in multiple copies) that effects signal sequence-mediated translocation of all secretory and lysosomal proteins and integration of all integral membrane proteins whose port of entry is the rough endoplasmic reticulum (G. Blobel 1980 Proc. natn. Acad. Sci. U.S.A. 77, 1496-1500). Two proteins have been isolated that are components of the r.e.r. translocation system. Their properties and function in protein translocation across and integration into membranes are discussed. PMID:6131460

  6. Aerosol emissions from forest and grassland burnings in the southern amazon basin and central Brazil

    NASA Astrophysics Data System (ADS)

    Leslie, Alistair C. D.

    1981-03-01

    Forest and grassland clearing by means of prescribed fires in tropical areas of the world may be responsible for large inputs of fine particulates to the global atmosphere besides being a major source of trace gases. The major continents on which extensive biomass burning takes place are Africa and South America. Such agricultural practices of burning have been employed throughout man's existence, but the importance and significance of such burning relative to anthropogenic industrial emissions to the atmosphere has not until extremely recently been seriously studied. In August-September 1979 project "Brushfire 1979" took place based in Brasília, Brazil. The Air Quality Division of the National Center for Atmospheric Research made ground level and aircraft measurements of trace gases (e.g. CO 2, CO, CH 4, N 2O, H 2, CH 3Cl, COS, NO, NO 2, O 3) and Florida State University sampled ground level aerosol emissions from grass and forest burnings. Aerosols were sampled using plastic 7-stage single orifice cascade impactors and FSU type linear and circular "streakers". Long term sampling was made of regional background for total particulates (<15 μmad) with 2 h resolution using streakers and with impactors for 24 h resolution of 7 particle size fractions (<0.25 to >8 μmad). Short term sampling within grass or forest fires was made using impactors incorporated into portable kits containing 4 miniature 12-18 V dc Brailsford pumps and a disposable dry cell power pack. Sampling times of 5-15 min were found optimal under these conditions. Grass fires were sampled in the savannah area northeast of Brasília and forest fires in the state of Mato Grosso on the southern edge of the dryland forest of the Amazon basin. Residual ash samples were collected. All of the samples were analyzed at Florida State University using PIXE for 15-20 elements including Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb and Sr. Computer reduction of the X-ray spectra was made

  7. Controls on rind thickness on basaltic andesite clasts weathering in Guadeloupe

    USGS Publications Warehouse

    Sak, P.B.; Navarre-Sitchler, A. K.; Miller, C.E.; Daniel, C.C.; Gaillardet, J.; Buss, H.L.; Lebedeva, M.I.; Brantley, S.L.

    2010-01-01

    A clast of low porosity basaltic andesite collected from the B horizon of a soil developed on a late Quaternary volcaniclastic debris flow in the Bras David watershed on Basse-Terre Island, Guadeloupe, exhibits weathering like that observed in many weathered clasts of similar composition in other tropical locations. Specifically, elemental profiles measured across the core-rind interface document that primary minerals and glass weather to Fe oxyhydroxides, gibbsite and minor kaolinite in the rind. The earliest reaction identified in the core is oxidation of Fe in pyroxene but the earliest reaction that creates significant porosity is plagioclase dissolution. Elemental loss varies in the order Ca???Na>K???Mg>Si>Al>Fe???P??Ti, consistent with the relative reactivity of phases in the clast from plagioclase???pyroxene???glass>apatite>ilmenite. The rind surrounds a core of unaltered material that is more spherical than the original clast. The distance from the core-rind boundary to a visually prominent rind layer, L, was measured as a proxy for the rind thickness at 36 locations on a slab cut vertically through the nominal center of the clast. This distance averaged 24.4??3.1mm. Maximum and minimum values for L, 35.8 and 20.6mm, were observed where curvature of the core-rind boundary is greatest (0.12mm-1) and smallest (0.018mm-1) respectively. Extrapolating from other rinds in other locations, the rate of rind formation is estimated to vary by a factor of about 2 (from ~4 to 7??10-14ms-1) from low to high curvature. The observation of a higher rate of rind formation for a higher curvature interface is consistent with a diffusion-limited model for weathering rind formation. The diffusion-limited model predicts that, like rind thickness, values of the thickness of the reaction front (h) for a given reaction, defined as the zone over which a parent mineral such as plagioclase completely weathers to rind material, should also increase with curvature. Values of h were

  8. Estimating Thermal Inertia with a Maximum Entropy Boundary Condition

    NASA Astrophysics Data System (ADS)

    Nearing, G.; Moran, M. S.; Scott, R.; Ponce-Campos, G.

    2012-04-01

    Thermal inertia, P [Jm-2s-1/2K-1], is a physical property the land surface which determines resistance to temperature change under seasonal or diurnal heating. It is a function of volumetric heat capacity, c [Jm-3K-1], and thermal conductivity, k [Wm-1K-1] of the soil near the surface: P=√ck. Thermal inertia of soil varies with moisture content due the difference between thermal properties of water and air, and a number of studies have demonstrated that it is feasible to estimate soil moisture given thermal inertia (e.g. Lu et al, 2009, Murray and Verhoef, 2007). We take the common approach to estimating thermal inertia using measurements of surface temperature by modeling the Earth's surface as a 1-dimensional homogeneous diffusive half-space. In this case, surface temperature is a function of the ground heat flux (G) boundary condition and thermal inertia and a daily value of P was estimated by matching measured and modeled diurnal surface temperature fluctuations. The difficulty is in measuring G; we demonstrate that the new maximum entropy production (MEP) method for partitioning net radiation into surface energy fluxes (Wang and Bras, 2011) provides a suitable boundary condition for estimating P. Adding the diffusion representation of heat transfer in the soil reduces the number of free parameters in the MEP model from two to one, and we provided a sensitivity analysis which suggests that, for the purpose of estimating P, it is preferable to parameterize the coupled MEP-diffusion model by the ratio of thermal inertia of the soil to the effective thermal inertia of convective heat transfer to the atmosphere. We used this technique to estimate thermal inertia at two semiarid, non-vegetated locations in the Walnut Gulch Experimental Watershed in southeast AZ, USA and compared these estimates to estimates of P made using the Xue and Cracknell (1995) solution for a linearized ground heat flux boundary condition, and we found that the MEP-diffusion model produced

  9. The effect of prospective monitoring and early physiotherapy intervention on arm morbidity following surgery for breast cancer: a pilot study.

    PubMed

    Singh, Chiara; De Vera, Mary; Campbell, Kristin L

    2013-01-01

    Objectif : Un taux de morbidité considérable est constaté à la suite de chirurgie pour le cancer du sein, et malgré cela, la physiothérapie ne constitue pas un aspect habituel des soins. Cette étude vise à comparer l'effet d'une ligne de soins cliniques qui comprend une éducation préopératoire, un suivi prospectif et de la physiothérapie précoce (à titre expérimental) à l'éducation préopératoire seule (comparaison) sur la morbidité du bras après une chirurgie de cancer du sein. Méthodologie : Une étude prospective quasi expérimentale prétest, post-test, avec groupe témoin non équivalent a été utilisée pour comparer deux sites cliniques, dont le site A a reçu l'intervention (n=41) et le site B, l'intervention de contrôle (n=31). Initialement (en phase préopératoire) et en phase postopératoire après 7 mois, l'amplitude articulaire (ADM) de l'épaule, la force du membre supérieur, la circonférence du membre supérieur, la douleur et la fonction du membre supérieur ainsi que la qualité de vie ont été évaluées. Résultats : Le groupe expérimental a pu maintenir une ADM de l'épaule en flexion à 7 mois, alors que l'amplitude articulaire avait diminué dans le groupe de comparaison (moyen [écart-type] 1° [9°] comparativement à −6° [15°], p=0,03). Une plus faible incidence de morbidité du bras et une meilleure qualité de vie ont été observées dans le groupe expérimental comparativement au groupe de comparaison; toutefois, les conclusions obtenues ne sont pas significatives sur le plan statistique. Les caractéristiques initiales et les approches chirurgicales différaient dans les deux sites, ce qui pourrait avoir influé sur les résultats obtenus. Conclusion : Les résultats initiaux sont prometteurs et appuient la faisabilité de l'intégration d'une approche de surveillance aux soins de suivi. Cette étude pilote pourrait fournir les bases d'un essai plus important et plus concluant.

  10. Oligomer Formation Reactions of Criegee Intermediates in the Ozonolysis of Small Unsaturated Hydrocarbons

    NASA Astrophysics Data System (ADS)

    Sakamoto, Y.; Inomata, S.; Hirokawa, J.

    2013-12-01

    hydroperoxides of low volatility formed in the gas phase are partitioned into the particle phase to contribute to the SOA formation. Here, we propose a new oligomer formation mechanism including sequential addition of Criegee intermediates to hydroperoxides. REFERENCE: (1)Kroll, J. H.; Seinfeld, J. H. Chemistry of Secondary Organic Aerosol: Formation and Evolution of Low-Volatility Organics in the Atmosphere. Atmos. Environ. 2008, 42, 3593-3624. (2)Sadezky, A.; Chaimbault, P.; Mellouki, A.; Roempp, A.; Winterhalter, R.; Le Bras, G.; Moortgat, G. K. Formation of Secondary Organic Aerosol and Oligomers from the Ozonolysis of Enol Ethers. Atmos. Chem. Phys. 2006, 6, 5009-5024. (3)Sadezky, A.; Winterhalter, R.; Kanawati, B.; Roempp, A.; Spengler, B.; Mellouki, A.; Le Bras, G.; Chaimbault, P.; Moortgat, G. K. Oligomer Formation during Gas-Phase Ozonolysis of Small Alkenes and Enol Ethers: New Evidence for the Central Role of the Criegee Intermediate as Oligomer Chain Unit. Atmos. Chem. Phys. 2008, 8, 2667-2699. (4)Klotz, B.; Barnes, I.; Imamura, T. Product Study of the Gas-Phase Reactions of O3, OH and NO3 Radicals with Methyl Vinyl Ether. Phys. Chem. Chem. Phys. 2004, 6, 1725-1734.

  11. Precambrian Cratons and Fold-Belts in Brazil: Overview

    NASA Astrophysics Data System (ADS)

    Fuck, R.

    2008-05-01

    The main Precambrian terrains recognized in Brazil comprise the Amazonian, São Francisco and Rio de la Plata cratons, surrounded by Neoproterozoic Brasiliano fold belts, making up the Borborema, Mantiqueira and Tocantins provinces. The Amazonian craton comprises an Archean core, surrounded by Paleoproterozoic terrains (Maroni-Itacaiunas, Ventuari-Tapajós, Rio Negro-Juruena), which southwestwards give way to the Mesoproterozoic Rondoniano-San Ignacio and Sunsas belts, the latter thought to be related to the Grenville belt of North America. The São Francisco craton comprises several Archean blocks (Gavião, Serrinha, Jequié) amalgamated by the Paleoproterozoic high-grade Itabuna-Salvador-Curaçá orogen. The Rio de la Plata craton, largely covered by Phanerozoic strata, is made of Paleoproterozoic basement gneiss and several Paleoproterozoic greenstone belts. Other cratonic blocks are hidden below large Phanerozoic basins, like the Paranapanema and Parnaíba blocks below the Paraná and Parnaíba basins, respectively. Several smaller Archean/Paleoproterozoic blocks appear within the Brasiliano provinces: some were strongly reworked during the Neoproterozoic orogenic events (São José do Campestre, Pernambuco-Alagoas, Goiás, Guanhães, Juiz de Fora, Curitiba), others were only marginally affected (São Luiz, Rio Apa, Luís Alves). The Brasiliano provinces are the result of Neoproterozoic to early Paleozoic orogenic events within the framework of West Gondwana amalgamation. The Mantiqueira Province extends from eastern Brazil to southern Uruguay and includes the Araçuaí, Ribeira and Dom Feliciano fold belts, bordering the São Francisco, Paranapanema and Rio de la Plata cratons and surrounding the Luís Alves craton. The Tocantins province in central Brazil includes the Araguaia, Paraguay and Brasília fold belts, the former bordering the Amazonian craton, the second bordering both the southern Amazonian craton and the Rio Apa block, and the last established on

  12. Astronomy in High School: Using a Mini-Planetarium to Understand Details of the Apparent Movement of Stars. (Spanish Title: Astronomía en la Escuela Secundaria: Comprendiendo los Detalles del Movimiento Aparente de Las Estrellas con un Miniplanetario.) Astronomia no Ensino Médio: Compreendendo Detalhes do Movimento Aparente das Estrelas com um Miniplanetário

    NASA Astrophysics Data System (ADS)

    dos Santos Leão, Demetrius

    2013-07-01

    en la comprensión de estas cuestiones y demostraron un gran interés por esta metodología. O objetivo deste artigo é apresentar parte dos resultados obtidos com a intervenção feita como projeto da dissertação de mestrado do autor, que consistiu no desenvolvimento de um conjunto de aulas de Astronomia, com alunos do 1º Ano do Ensino Médio de uma escola da rede privada do Distrito Federal (Brasília, Brasil), empregando como recurso principal um material didático chamado miniplanetário (MP). Utilizando como pressuposto teórico norteador dessas aulas as ideias de contextualização e dialogicidade de Paulo Freire, foi proposta aos estudantes a montagem e utilização desse recurso em uma sessão de planetário. Durante o projeto, enfatizaram-se assuntos como a trajetória aparente das estrelas para o céu de Brasília, a localização dos pontos cardeais a partir da constelação do Cruzeiro do Sul, as cores das estrelas e as estrelas vistas de uma determinada localidade. Apurou-se que os alunos apresentaram melhoria na compreensão desses assuntos, bem como demonstraram expressiva empolgação com essa metodologia desenvolvida.

  13. Inter-relationship between scaling exponents for describing self-similar river networks

    NASA Astrophysics Data System (ADS)

    Yang, Soohyun; Paik, Kyungrock

    2015-04-01

    Natural river networks show well-known self-similar characteristics. Such characteristics are represented by various power-law relationships, e.g., between upstream length and drainage area (exponent h) (Hack, 1957), and in the exceedance probability distribution of upstream area (exponent ɛ) (Rodriguez-Iturbe et al., 1992). It is empirically revealed that these power-law exponents are within narrow ranges. Power-law is also found in the relationship between drainage density (the total stream length divided by the total basin area) and specified source area (the minimum drainage area to form a stream head) (exponent η) (Moussa and Bocquillon, 1996). Considering that above three scaling relationships all refer to fundamental measures of 'length' and 'area' of a given drainage basin, it is natural to hypothesize plausible inter-relationship between these three scaling exponents. Indeed, Rigon et al. (1996) demonstrated the relationship between ɛ and h. In this study, we expand this to a more general ɛ-η-h relationship. We approach ɛ-η relationship in an analytical manner while η-h relationship is demonstrated for six study basins in Korea. Detailed analysis and implications will be presented. References Hack, J. T. (1957). Studies of longitudinal river profiles in Virginia and Maryland. US, Geological Survey Professional Paper, 294. Moussa, R., & Bocquillon, C. (1996). Fractal analyses of tree-like channel networks from digital elevation model data. Journal of Hydrology, 187(1), 157-172. Rigon, R., Rodriguez-Iturbe, I., Maritan, A., Giacometti. A., Tarboton, D. G., & Rinaldo, A. (1996). On Hack's Law. Water Resources Research, 32(11), 3367-3374. Rodríguez-Iturbe, I., Ijjasz-Vasquez, E. J., Bras, R. L., & Tarboton, D. G. (1992). Power law distributions of discharge mass and energy in river basins. Water Resources Research, 28(4), 1089-1093.

  14. The new physician as unwitting quantum mechanic: is adapting Dirac's inference system best practice for personalized medicine, genomics, and proteomics?

    PubMed

    Robson, Barry

    2007-08-01

    What is the Best Practice for automated inference in Medical Decision Support for personalized medicine? A known system already exists as Dirac's inference system from quantum mechanics (QM) using bra-kets and bras where A and B are states, events, or measurements representing, say, clinical and biomedical rules. Dirac's system should theoretically be the universal best practice for all inference, though QM is notorious as sometimes leading to bizarre conclusions that appear not to be applicable to the macroscopic world of everyday world human experience and medical practice. It is here argued that this apparent difficulty vanishes if QM is assigned one new multiplication function @, which conserves conditionality appropriately, making QM applicable to classical inference including a quantitative form of the predicate calculus. An alternative interpretation with the same consequences is if every i = radical-1 in Dirac's QM is replaced by h, an entity distinct from 1 and i and arguably a hidden root of 1 such that h2 = 1. With that exception, this paper is thus primarily a review of the application of Dirac's system, by application of linear algebra in the complex domain to help manipulate information about associations and ontology in complicated data. Any combined bra-ket can be shown to be composed only of the sum of QM-like bra and ket weights c(), times an exponential function of Fano's mutual information measure I(A; B) about the association between A and B, that is, an association rule from data mining. With the weights and Fano measure re-expressed as expectations on finite data using Riemann's Incomplete (i.e., Generalized) Zeta Functions, actual counts of observations for real world sparse data can be readily utilized. Finally, the paper compares identical character, distinguishability of states events or measurements, correlation, mutual information, and orthogonal character, important issues in data mining

  15. Debye process in Ibuprofen glass-forming liquid: insights from molecular dynamics simulation.

    PubMed

    Affouard, F; Correia, Natália T

    2010-09-01

    By means of molecular dynamics simulations, dynamical properties of racemic ibuprofen glass-forming liquid are investigated at different temperatures from 360 to 500 K. The origin of the peculiar low amplitude Debye-type relaxation observed experimentally by dielectric relaxation spectroscopy is addressed (Bras, A. R.; Noronha, J. P.; Antunes, A. M. M.; Cardoso, M. M.; Schonhals, A.; Affouard, F.; Dionisio, M.; Correia, N. T. J. Phys. Chem. B 2008, 112, 11087). Single and total dipolar autocorrelation functions are calculated. It is found that the behavior of the total dipole correlation is dominated at short and long times by the single function. It mainly originates from the antiparallel dipoles correlations in agreement with a value of the Kirkwood correlation factor slightly smaller than unity. The simulation suggests that the long time Debye-type decay of the dipole-dipole correlation is dominated by the internal cis-trans conversion of the O=C-O-H group coupled to the change of the intermolecular linear/cyclic HB structures. The overall rotation of the molecules is about 1-2 decades faster than the cis to trans transformation, so all the O=C-O-H group environments are equal on average. The effective rotational potential energy barriers of the O=C-O-H groups due to the surroundings are thus averaged and dipolar relaxation follows a simple Debye law. It is found that cyclic dimers inhibit the cis to trans conversion unlike the linear dimers and trimers which favor this conversion and stabilize the trans isomer. It is well in line with the very low amplitude of the dielectric strength associated with the Debye relaxation observed experimentally and its increase when the liquid is maintained isothermally above the melting temperature since this amplitude mainly relates to the low fraction of ibuprofen molecules in the trans conformation. A comparison is made with the Debye-type relaxation found in microstructured monohydroxy alcohols.

  16. Mortality due to Cardiovascular Diseases in Women and Men in the Five Brazilian Regions, 1980-2012

    PubMed Central

    Mansur, Antonio de Padua; Favarato, Desidério

    2016-01-01

    Background: Studies have shown different mortalities due to cardiovascular diseases (CVD), ischemic heart disease (IHD) and cerebrovascular diseases (CbVD) in the five Brazilian regions. Socioeconomic conditions of those regions are frequently used to justify differences in mortality due to those diseases. In addition, studies have shown a reduction in the differences between the mortality rates of the five Brazilian regions. Objective: To update CVD mortality data in women and men in the five Brazilian regions. Methods: Mortality and population data were obtained from the Brazilian Institute of Geography and Statistics and Ministry of Health. Risk of death was adjusted by use of the direct method, with the 2000 world standard population as reference. We analyzed trends in mortality due to CVD, IHD and CbVD in women and men aged ≥ 30 years in the five Brazilian regions from 1980 to 2012. Results: Mortality due to: 1) CVD: showed reduction in the Northern, West-Central, Southern and Southeastern regions; increase in the Northeastern region; 2) IHD: reduction in the Southeastern and Southern regions; increase in the Northeastern region; and unchanged in the Northern and West-Central regions; 3) CbVD: reduction in the Southern, Southeastern and West-Central regions; increase in the Northeastern region; and unchanged in Northern region. There was also a convergence in mortality trends due to CVD, IHD, and CbVD in the five regions. Conclusion: The West-Central, Northern and Northeastern regions had the worst trends in CVD mortality as compared to the Southeastern and Southern regions. (Arq Bras Cardiol. 2016; [online].ahead print, PP.0-0) PMID:27437866

  17. Mortality due to respiratory diseases in the elderly after influenza vaccination campaigns in the Federal District, Brazil, 1996-2009 *

    PubMed Central

    Scoralick, Francisca Magalhães; Piazzolla, Luciana Paganini; Pires, Liana Laura; Neri, Cleudsom; de Paula, Wladimir Kummer

    2013-01-01

    OBJECTIVE: To compare mortality rates due to respiratory diseases among elderly individuals residing in the Federal District of Brasília, Brazil, prior to and after the implementation of a national influenza vaccination campaign. METHODS: This was an ecological time series analysis. Data regarding the population of individuals who were over 60 years of age between 1996 and 2009 were obtained from official databases. The variables of interest were the crude mortality rate (CMR), the mortality rate due to the respiratory disease (MRRD), and the proportional mortality ratio (PMR) for respiratory diseases. We performed a qualitative analysis of the data for the period prior to and after the implementation of the vaccination campaign (1996-1999 and 2000-2009, respectively). RESULTS: The CMR increased with advancing age. Over the course of the study period, we observed reductions in the CMR in all of the age brackets studied, particularly among those aged 80 years or older. Reductions in the MRRD were also found in all of the age groups, especially in those aged 80 years or older. In addition, there was a decrease in the PMR for respiratory diseases in all age groups throughout the study period. The most pronounced decrease in the PMR for respiratory diseases in the ≥ 70 year age bracket occurred in 2000 (immediately following the implementation of the national vaccination campaign); in 2001, that rate increased in all age groups, despite the greater adherence to the vaccination campaign in comparison with that recorded for 2000. CONCLUSIONS: Influenza vaccination appears to have a positive impact on the prevention of mortality due to respiratory diseases, particularly in the population aged 70 or over. PMID:23670505

  18. The "normal" elongation of river basins

    NASA Astrophysics Data System (ADS)

    Castelltort, Sebastien

    2013-04-01

    The spacing between major transverse rivers at the front of Earth's linear mountain belts consistently scales with about half of the mountain half-width [1], despite strong differences in climate and rock uplift rates. Like other empirical measures describing drainage network geometry this result seems to indicate that the form of river basins, among other properties of landscapes, is invariant. Paradoxically, in many current landscape evolution models, the patterns of drainage network organization, as seen for example in drainage density and channel spacing, seem to depend on both climate [2-4] and tectonics [5]. Hovius' observation [1] is one of several unexplained "laws" in geomorphology that still sheds mystery on how water, and rivers in particular, shape the Earth's landscapes. This narrow range of drainage network shapes found in the Earth's orogens is classicaly regarded as an optimal catchment geometry that embodies a "most probable state" in the uplift-erosion system of a linear mountain belt. River basins currently having an aspect away from this geometry are usually considered unstable and expected to re-equilibrate over geological time-scales. Here I show that the Length/Width~2 aspect ratio of drainage basins in linear mountain belts is the natural expectation of sampling a uniform or normal distribution of basin shapes, and bears no information on the geomorphic processes responsible for landscape development. This finding also applies to Hack's [6] law of river basins areas and lengths, a close parent of Hovius' law. [1]Hovius, N. Basin Res. 8, 29-44 (1996) [2]Simpson, G. & Schlunegger, F. J. Geophys. Res. 108, 2300 (2003) [3]Tucker, G. & Bras, R. Water Resour. Res. 34, 2751-2764 (1998) [4]Tucker, G. & Slingerland, R. Water Resour. Res. 33, 2031-2047 (1997) [5]Tucker, G. E. & Whipple, K. X. J. Geophys. Res. 107, 1-1 (2002) [6]Hack, J. US Geol. Surv. Prof. Pap. 294-B (1957)

  19. Prevalence of enamel defects and associated risk factors in both dentitions in preterm and full term born children

    PubMed Central

    CRUVINEL, Vanessa Resende Nogueira; GRAVINA, Danuze Batista Lamas; AZEVEDO, Tatiana Degani Paes Leme; de REZENDE, Catharina Siqueira; BEZERRA, Ana Cristina Barreto; de TOLEDO, Orlando Ayrton

    2012-01-01

    Objectives The aim of this study was to evaluate the prevalence of enamel defects and their risk factors on primary and permanent dentitions of prematurely born children and full-term born children born at Regional Hospital of Asa Sul, Brasília, DF, Brazil. Material and Methods Eighty 5-10-year-old children of both genders were examined, being 40 born prematurely (G1) and 40 born full term (G2). The demographic variables, medical history and oral health behaviors were retrieved using a questionnaire and data obtained from clinical examination were recorded. The teeth were examined and the presence of enamel defects was diagnosed according to the DDE Index and registered in odontograms. Subsequently, the defects were categorized in four groups according to one of the criteria proposed in 1992 by the FDI Commission on Oral Health, Research and Epidemiology. Kruskal-Wallis, Chi-square, Kappa, Mann-Whitney tests and logistic regression were used for statistical analysis. Results 75% of total sample had enamel defects. There was a major prevalence of hypoplasia of the enamel in G1 (p<0.001). There was a significant relationship between low weight and presence of the imperfections on the enamel in G1 on the primary dentition. The logistic regression model showed that the other risk factors such as monthly per capita family income, educational level, dietary and hygiene habits, fluoride exposure, trauma, and diseases were not associated with enamel defects and caries. Conclusions Pre-term labor can be a predisposing factor for the presence of the enamel hypoplasia in the primary dentition. PMID:22858696

  20. A Study of Physical-Chemical Effects on the Atmosphere of the Southern Hemisphere During Forbush Decrease Periods

    NASA Astrophysics Data System (ADS)

    Portugal, W.; Pacini, A. A.; Echer, E.; Echer, M. P. D. S.

    2015-12-01

    We present here a study about some possible physical-chemical changes on the Southern hemisphere atmosphere, in Brazil, due to galactic cosmic rays (GCR) flux decreases (Forbush Decreases). Galactic Cosmic Rays are energetic particles that come from interstellar medium and arrive on the Earth isotropically and continuously. These particles interact with atmosphere constituents and induce the ionization of the neutral atmosphere. It is known that the presence of ions on the troposphere can change the vapor condensation patterns, since some ions can behave like cloud condensation nuclei. So, there is a work hypothesis, that the GCR flux decrease can cause some change on the physical-chemical of the atmosphere. We have investigated this possible effect, using three periods of Forbush Decrease effects (Nov/01, Oct/03 e Jul/12) with different magnitudes, on three different latitudinal range of Brazilian sector, Porto Alegre (30.08o S , YY O); Brasília (15.75o S , YY O) and Belém (1.46o S , YY O). The atmospheric effects are assessed by analysis of the temperature, pressure, humidity and aerossol data profiles, since the surface up to stratosphere. We have also studied, for comparison, high latitude atmosphere by atmospheric data from Jokioinen - Filand (60.8o N , 23.5o E) for the same three FDs. Then, our aim with this study is to investigate possible GCR decreases effects in the lower atmosphere at high, medium and low latitudes. The results obtained in this study will be compared with previous published works.

  1. Fractionation of stable isotopes in perchlorate and nitrate during in situ biodegradation in a sandy aquifer

    SciTech Connect

    Hatzinger, Paul B.; Bohlke, J. K.; Sturchio, N. C.; Gu, Baohua

    2009-01-01

    An in situ experiment was performed in a shallow alluvial aquifer in Maryland to quantify the fractionation of stable isotopes in perchlorate (Cl and O) and nitrate (N and O) during biodegradation. An emulsified soybean oil substrate that was previously injected into this aquifer provided the electron donor necessary for biological perchlorate reduction and denitrification. During the field experiment, groundwater extracted from an upgradient well was pumped into an injection well located within the in situ oil barrier, and then groundwater samples were withdrawn for the next 30 h. After correction for dilution (using Br-as a conservative tracer of the injectate), perchlorate concentrations decreased by 78 % and nitrate concentrations decreased by 87 %, during the initial 8.6 h after the injection. The observed ratio of fractionation effects of O and Cl isotopes in perchlorate (ε18O/ε37Cl) was 2.6, which is similar to that observed in the laboratory using pure cultures (2.5). Denitrification by indigenous bacteria fractionated O and N isotopes in nitrate at a ratio of approximately 0.8 (ε18O/ε15N), which is within the range of values reported previously for denitrification. However, the magnitudes of the individual apparent in situ isotope fractionation effects for perchlorate and nitrate were appreciably smaller than those reported in homogeneous closed systems (0.2 to 0.6 times), even after adjustment for dilution. These results indicate that (1) isotope fractionation factor ratios (ε18O/ε37Cl, ε18O/ε15N) derived from homogeneous laboratory systems (e.g., pure culture studies) can be used qualitatively to confirm the occurrence of in situ biodegradation of both perchlorate and nitrate, but (2) the magnitudes of the individual apparent  values cannot be used quantitatively to estimate the in situ extent of biodegradation of either anion.

  2. Cost estimate of hospital stays for premature newborns in a public tertiary hospital in Brazil

    PubMed Central

    Desgualdo, Claudia Maria; Riera, Rachel; Zucchi, Paola

    2011-01-01

    OBJECTIVES: To estimate the direct costs of hospital stays for premature newborns in the Interlagos Hospital and Maternity Center in São Paulo, Brazil and to assess the difference between the amount reimbursed to the hospital by the Unified Health System and the real cost of care for each premature newborn. METHODS: A cost-estimate study in which hospital and professional costs were estimated for premature infants born at 22 to 36 weeks gestation during the calendar year of 2004 and surviving beyond one hour of age. Direct costs included hospital services, professional care, diagnoses and therapy, orthotics, prosthetics, special materials, and blood products. Costs were estimated using tables published by the Unified Health System and the Brasíndice as well as the list of medical procedures provided by the Brazilian Classification of Medical Procedures. RESULTS: The average direct cost of care for initial hospitalization of a premature newborn in 2004 was $2,386 USD. Total hospital expenses and professional services for all premature infants in this hospital were $227,000 and $69,500 USD, respectively. The costs for diagnostic testing and blood products for all premature infants totaled $22,440 and $1,833 USD. The daily average cost of a premature newborn weighing less than 1,000 g was $115 USD, and the daily average cost of a premature newborn weighing more than 2,500 g was $89 USD. Amounts reimbursed to the hospital by the Unified Health System corresponded to only 27.42% of the real cost of care. CONCLUSIONS: The cost of hospital stays for premature newborns was much greater than the amount reimbursed to the hospital by the Unified Health System. The highest costs corresponded to newborns with lower birth weight. Hospital costs progressively and discretely decreased as the newborns' weight increased. PMID:22012050

  3. Genetic parameters and breeding strategies for high levels of iron and zinc in Phaseolus vulgaris L.

    PubMed

    Martins, S M; Melo, P G S; Faria, L C; Souza, T L P O; Melo, L C; Pereira, H S

    2016-01-01

    One of the current focus of common bean breeding programs in Brazil is to increase iron (FeC) and zinc content (ZnC) in grains. The objectives of this study were to estimate genetic parameters for FeC and ZnC in common bean, verify the need for conducting multi-site evaluation tests, identify elite lines that combine high FeC and ZnC with good adaptability, stability, and agronomic potential, and examine the genetic association between FeC and ZnC. Elite lines (140) were evaluated for important agronomic traits in multiple environments. In one trial, FeC and ZnC were evaluated and genetic parameters were estimated. Based on the high heritability estimates and significant selection gains obtained, the conditions for a successful selection was favorable. Of the 140 evaluated lines, 17 had higher FeC and ZnC, and were included in the validation test (2013, five environments), specifically for the evaluation of FeC and ZnC. The line by environment interaction for FeC and ZnC was detected, but it was predominantly simple. The environmental effect strongly influenced FeC and ZnC . The environment Brasília/rainy season was selected as the best evaluation site for preliminary tests for FeC and ZnC, because it resulted in similar conclusions as the mean of the five environments. The lines CNFP 15701 and CNFC 15865 had higher FeC and ZnC and were highly adaptable and stable, and are recommended for utilization in breeding programs. The lines CNFC 15833, CNFC 15703, and CNFP 15676 showed excellent combined agronomic and nutritional traits, and were selected for the development of biofortified cultivars. Additionally, the genetic association between FeC and ZnC was detected. PMID:27323172

  4. [Child prostitution: family disintegration, necessary planning, the laziness of the elite].

    PubMed

    1993-09-01

    Child and juvenile prostitution in Brazil has reached such proportions that a parliamentary commission launched an inquiry. The Brazilian Center of Children and Adolescents (CBIA) estimated that there are about 500,000 such prostitutes in the country, a record in Latin America. This type of prostitution flourishes in poor urban areas and in the North and Central-East. Not only girls become prostitutes; in Rio de Janeiro, 4000 boys cater to tourists from the industrialized world. 79% of these youngsters say that they use condoms, but 42% are infected with HIV. In many cases their families tolerate their homosexual encounters because of the extra income received. In the interior of the state of Rio, girls aged 11-15 years are enticed to cities as domestics and end up in prostitution. In Niteroi there is a prostitution network specializing in 13-year-old girls. Although there are 30,000 prostitutes in the state of Rio, the distribution of condoms among them has caused negative reactions among conservatives and Catholics claiming that it would increase licentiousness. The Brazilian Center for the Defense of the Rights of Children and Adolescents countered that condoms help prevent the spread of diseases. In Para, Acre, and Rondonia, 13-, 14-, and 15-year-old girls sell their bodies in order to survive. In the maternity ward of Barbara Heliodora, Rio Branco, Acre, 31% of deliveries are to girls aged 10-16 years. In Sao Paulo and in the neighborhoods of Bras and Belem, girls as young as 10 years of age become prostitutes under the protection of corrupt police who exact sexual favors or a share of receipts. According to CBIA, 80% of sexual violence against children and adolescents occurs in the home, with fathers being the main aggressors. The prostitution of children and adolescents in Brazil is connected to the destruction of the family and is the result of misery and hunger.

  5. The Neoproterozoic-Cambrian Paraguay Belt, central Brazil: Part I - New structural data and a new approach on the regional implications

    NASA Astrophysics Data System (ADS)

    Silva, Luiz José Homem D'el-Rey; Walde, Detlef Hans-Gerd; Saldanha, Davi Oliveira

    2016-04-01

    Together with the Araguaia and Brasília belts, the Paraguay belt forms in central Brazil, the Tocantins Province that is one of the largest orogens of western Gondwana. The Corumbá area occupies the site where the northern and southern parts of the Paraguay belt form, together with the Chiquitos-Tucavaca aulacogen (stretching E-W in the adjacent Bolivian territory) an R-R-R basin system opened-filled in the ~ 700/650-540 Ma interval within the Amazon-Rio Apa paleo-continent. The sedimentary (volcanic) rocks of the Jacadigo and Corumbá Groups found around the Corumbá city record part of the Neoproterozoic-Cambrian passive margin precursor of the Paraguay belt. Our pioneer structural analysis reveals that these rocks experienced progressive deformation (phases D1-D2-D3) and low-grade metamorphism during the Brasiliano Cycle (540-513 Ma). The crystalline basement was also involved, according to structural data and K-Ar ages in the literature. The paleo-passive margin was thickened during the D1-D2 deformation and was lately shortened (D3) in two orthogonal directions, SE-NW (D3P) and SW-NE (D3T). Developed co-axially and verging to NW, D1-D2-D3P structures record the closure of the basin precursor of the Paraguay belt, whereas D3T structures seem related to the inversion of the aulacogen. Although the tectonic transport to NW, as observed in the Corumbá area, matches the reported transport of Paraguay belt's supracrustal rocks towards the eastern margin of the Rio Apa block and Araguaia belt's rocks towards the Amazon craton, the transport direction is opposite in other parts of the Paraguay belt. Our comprehensive discussion of these facts brings to light profound regional implications.

  6. Fotometria WHBY |o lll|/HB de Regiones H 11 Y la HISTORIA de la Formacion ESTELAR Reciente EN la PEQUENA NUBE de Magallanes

    NASA Astrophysics Data System (ADS)

    Copetti, M. V. F.; Dottori, H. A.

    1987-05-01

    El ancho equivalente WHβ de la linea de Hβ en emisión y la razón [0 III]/Hβ del par λλ4959, 50 7 A del [0111], fueron medidos en 23 regiones HII de la Peque˜a Nube de Magallanes, por medio de la fotometría fotoeléctrica a través de un sistema de tres filtros interferenciales: dos Hβ , con bandas pasantes de 100 y 30 A, y un [0111] centrado en 5000 A y con banda pasante de 50 A. Las observaciones fueron realizadas con los telescopios de 1.60-m y 0.60-m del Laboratorio Nacional de Astrofísica, Brasópolis, Brasil. Fueron escogidos diafragmas suficientemente grandes para captar la radiación integrada de cada región HII. Las medidas fueron calibradas por comparación a un conjunto de nebulosas planetarias con flujos absolutos bien definidos. A través de la comparación entre los datos observacionales y modelos evolutivos de WHβ y [0 III] /Hβ (Copetti et al.1986', Astr. and Ap., 156, 111), las edades de las regiones HIl fueron estimadas. Basada en la distribución espacial de las edades de regiones HIl, la historia de la formación estelar reciente en la Pequeña Nube de Magallanes es analizada. La similitud de las medidas de WH&beta y [OIII]/WHβ entre las regiones H II observadas sugiere que hubo una explosión de formación estelar a 4±1 x106 años en la Pequeña Nube de Magallanes. (Parcialmente financiado por CNPq).

  7. Association between temporomandibular disorders and abnormal head postures.

    PubMed

    Faulin, Evandro Francisco; Guedes, Carlos Gramani; Feltrin, Pedro Paulo; Joffiley, Cláudia Maria Mithie Suda Costa

    2015-01-01

    This study examines the possible correlation between the prevalence of temporomandibular disorders (TMD) and different head postures in the frontal and sagittal planes using photographs of undergraduate students in the School of Dentistry at the Universidade de Brasília - UnB, Brazil. In this nonrandomized, cross-sectional study, the diagnoses of TMD were made with the Research Diagnostic Criteria (RDC)/TMD axis I. The craniovertebral angle was used to evaluate forward head posture in the sagittal plane, and the interpupillary line was used to measure head tilt in the frontal plane. The measurements to evaluate head posture were made using the Software for the Assessment of Posture (SAPO). Students were divided into two study groups, based on the presence or absence of TMD. The study group comprised 46 students and the control group comprised 80 students. Data about head posture and TMD were analyzed with the Statistical Package for the Social Sciences, version 13. Most cases of TMD were classified as degenerative processes (group III), followed by disk displacement (group II) and muscle disorders (group I). There was no sex predominance for the type of disorder. No association was found between prevalence rates for head postures in the frontal plane and the occurrence of TMD. The same result was found for the association of TMD diagnosis with craniovertebral angle among men and women, and the group that contained both men and women. Abnormal head postures were common among individuals both with and without TMD. No association was found between head posture evaluated in the frontal and sagittal planes and TMD diagnosis with the use of RDC/TMD.

  8. Space science public outreach at Louisiana State University

    NASA Astrophysics Data System (ADS)

    Guzik, T.; Babin, E.; Cooney, W.; Giammanco, J.; Hartman, D.; McNeil, R.; Slovak, M.; Stacy, J.

    Over the last seven years the Astronomy / Astrophysics group in the Department of Physics and Astronomy of Louisiana State University has developed an exten- sive Space Science education and public outreach program. This program includes the local park district (the Recreation and Park Commission for the Parish of East Baton Rouge, BREC), the local amateur astronomer group (the Baton Rouge As- tronomical Society, BRAS), the Louisiana Arts and Science Museum (LASM), and Southern University (SU, part of the largest HBCU system in the nation). Our effort has directly led to the development of the Highland Road Park Observatory (HRPO, http://www.bro.lsu.edu/hrpo) that supports student astronomy training at LSU and SU, amateur observations and a public program for adults and children, establishment of a series of teacher professional development workshops in astronomy and physics, and the "Robots for Internet Experiences (ROBIE)" project (http://www.bro.lsu.edu/) where we have several instruments (e.g. HAM radio, radio telescope, optical tele- scopes) that can be controlled over the internet by students and teachers in the class- room along with associated lessons developed by a teacher group. In addition, this year the LASM, will be opening a new planetarium / space theater in downtown Baton Rouge, Louisiana. We are currently working to bring live views of the heavens from the HRPO telescope to audiences attending planetarium shows and will be working closely with planetarium staff to develop shows that highlight LSU astronomy / space science research. During the presentation we will provide some details about our in- dividual projects, the overall structure of our program, establishing community links and some of the lessons we learned along the way. Finally, we would like to acknowl- edge NASA, Louisiana State University, the Louisiana Systemic Initiatives Program and the Louisiana Technology Innovation Fund for their support.

  9. The new physician as unwitting quantum mechanic: is adapting Dirac's inference system best practice for personalized medicine, genomics, and proteomics?

    PubMed

    Robson, Barry

    2007-08-01

    What is the Best Practice for automated inference in Medical Decision Support for personalized medicine? A known system already exists as Dirac's inference system from quantum mechanics (QM) using bra-kets and bras where A and B are states, events, or measurements representing, say, clinical and biomedical rules. Dirac's system should theoretically be the universal best practice for all inference, though QM is notorious as sometimes leading to bizarre conclusions that appear not to be applicable to the macroscopic world of everyday world human experience and medical practice. It is here argued that this apparent difficulty vanishes if QM is assigned one new multiplication function @, which conserves conditionality appropriately, making QM applicable to classical inference including a quantitative form of the predicate calculus. An alternative interpretation with the same consequences is if every i = radical-1 in Dirac's QM is replaced by h, an entity distinct from 1 and i and arguably a hidden root of 1 such that h2 = 1. With that exception, this paper is thus primarily a review of the application of Dirac's system, by application of linear algebra in the complex domain to help manipulate information about associations and ontology in complicated data. Any combined bra-ket can be shown to be composed only of the sum of QM-like bra and ket weights c(), times an exponential function of Fano's mutual information measure I(A; B) about the association between A and B, that is, an association rule from data mining. With the weights and Fano measure re-expressed as expectations on finite data using Riemann's Incomplete (i.e., Generalized) Zeta Functions, actual counts of observations for real world sparse data can be readily utilized. Finally, the paper compares identical character, distinguishability of states events or measurements, correlation, mutual information, and orthogonal character, important issues in data mining

  10. [Child prostitution: family disintegration, necessary planning, the laziness of the elite].

    PubMed

    1993-09-01

    Child and juvenile prostitution in Brazil has reached such proportions that a parliamentary commission launched an inquiry. The Brazilian Center of Children and Adolescents (CBIA) estimated that there are about 500,000 such prostitutes in the country, a record in Latin America. This type of prostitution flourishes in poor urban areas and in the North and Central-East. Not only girls become prostitutes; in Rio de Janeiro, 4000 boys cater to tourists from the industrialized world. 79% of these youngsters say that they use condoms, but 42% are infected with HIV. In many cases their families tolerate their homosexual encounters because of the extra income received. In the interior of the state of Rio, girls aged 11-15 years are enticed to cities as domestics and end up in prostitution. In Niteroi there is a prostitution network specializing in 13-year-old girls. Although there are 30,000 prostitutes in the state of Rio, the distribution of condoms among them has caused negative reactions among conservatives and Catholics claiming that it would increase licentiousness. The Brazilian Center for the Defense of the Rights of Children and Adolescents countered that condoms help prevent the spread of diseases. In Para, Acre, and Rondonia, 13-, 14-, and 15-year-old girls sell their bodies in order to survive. In the maternity ward of Barbara Heliodora, Rio Branco, Acre, 31% of deliveries are to girls aged 10-16 years. In Sao Paulo and in the neighborhoods of Bras and Belem, girls as young as 10 years of age become prostitutes under the protection of corrupt police who exact sexual favors or a share of receipts. According to CBIA, 80% of sexual violence against children and adolescents occurs in the home, with fathers being the main aggressors. The prostitution of children and adolescents in Brazil is connected to the destruction of the family and is the result of misery and hunger. PMID:12288821

  11. Checklist of aquatic and marshy Monocotyledons from the Araguaia River basin, Brazilian Cerrado

    PubMed Central

    Bove, Claudia

    2016-01-01

    Abstract Background The Araguaia River basin runs through the states of Goiás, Mato Grosso, Tocantins, and Pará, covering 373,000 Km2, mostly within the Brazilian Cerrado. The region has a wide variety of wetlands. The climate is characterized by high temperatures and strongly seasonal precipitation. There are two well defined seasons: the dry season (winter-spring) and the rainy season (summer- fall). The Araguaia River basin is dominated by plinthosoils that are found in low flat areas, poorly drained and prone to flooding, yielding wetland habitats of high plant diversity. Since the 1970s, human activities have led to reduction in both the diversity and area of wetlands. The construction of the Belém-Brasília highway and hydroelectric dams, as well as the expansion of agricultural and mining activities, have had major impacts on the region. New information The flora diversity data of the Araguaia River basin was developed through field work, herbarium research, and use of a database (Species Link). The resulting checklist of 162 aquatic and marshy monocotyledons from the Araguaia River basin represents 20 families and 50 genera. Cyperaceae (51 spp.), Poaceae (39 spp.), and Eriocaulaceae (16 spp.) are the most representative families. Life form analysis indicates that helophytes predominate (98 spp.; 60.5%). One hundred one species are native to tropical and/or subtropical America and twenty one are endemic to Brazil. Ninety-three species are new occurrences for the Araguaia River basin. Among them, three species are reported in the Brazilian Cerrado for the first time. This work contributes to the understanding of aquatic plant diversity in the Cerrado and other savanna-like vegetation physiognomies; environments and habitats poorly understood taxonomically and undercollected generally. PMID:27099550

  12. Stabilisation dynamique d'un winging scapula (à propos d'un cas avec revue de la littérature)

    PubMed Central

    Boukhris, Jalal; Boussouga, Mostapha; Jaafar, Abdelouahab; Bouslmame, Nabil

    2014-01-01

    Décrit pour la première fois par Velpeau en 1937, le winging scapula reste une affection rare, encore peu connue aussi bien du grand public que des professionnels de santé. Il s'agit en fait de la paralysie isolée du nerf thoracique long, responsable de l'innervation unique du muscle serratus antérieur, laquelle paralysie génère un décollement du bord spinal et de la pointe de l'omoplate, particulièrement visible lors des mouvements d'abduction et d'antépulsion du bras. Evoluant habituellement vers la récupération spontanée, le diagnostic de cette affection est essentiellement clinique, l'exploration électromyographique, peut appuyer le diagnostic et surtout servir d’élément de surveillance. Le traitement est avant tout conservateur; la chirurgie n’étant envisagée que dans les formes chroniques qui ne répondent pas à la rééducation, le cas d'ailleurs de notre patient. Le choix du type d'intervention devra obéir à des critères précis. La stabilisation dynamique de la scapula est une intervention séduisante et donne entre des mains entraînées des résultats très satisfaisants, beaucoup de critiques sont faites sur la récupération de la force musculaire, ce qui en limite l'indication quand les exigences professionnelles des patients sont importantes. Néanmoins, certaines séries en font la méthode de choix avec des résultats excellents. PMID:25918571

  13. First record of a nematode Metastrongyloidea (Aelurostrongylus abstrusus larvae) in Achatina (Lissachatina) fulica (Mollusca, Achatinidae) in Brazil.

    PubMed

    Thiengo, Silvana C; Fernandez, Monica A; Torres, Eduardo J L; Coelho, Pablo M; Lanfredi, Reinalda M

    2008-05-01

    Achatina (Lissachatina) fulica was introduced in Brazil in the 1980s for commercial purposes ("escargot" farming) and nowadays, mainly by human activity, it is widespread in at least 23 out of 26 Brazilian states and Brasília, including the Amazonian region and natural reserves, where besides a general nuisance for people it is a pest and also a public health concern, since it is one of the natural intermediate host of Angiostrongylus cantonensis, ethiological agent of the meningoencephalitis in Asia. As Brazil is experiencing the explosive phase of the invasion, the Laboratório de Malacologia do Instituto Oswaldo Cruz/Fiocruz has been receiving samples of these molluscs for identification and search for Angiostrongylus cantonensis and Angiostrongylus costaricensis larvae. While examining samples of A. fulica different nematode larvae were obtained, including Aelurostrongylus, whose different species are parasites of felids, dogs, primates, and badger. Morphological and morphometric analyses presented herein indicated the species Aelurostrongylus abstrusus, as well as the occurrence of other nematode larvae (Strongyluris-like) found in the interior of the pallial cavity of A. fulica. This is the first report in Brazil of the development of A. abstrusus infective larvae in A. fulica evidencing the veterinary importance of this mollusc in the transmission of A. abstrusus to domestic cats. Since the spread of A. fulica is pointed out in the literature as one of the main causative spread of the meningoencephalitis caused by A. cantonensis the authors emphasize the need of sanitary vigilance of snails and rats from vulnerable areas for A. cantonensis introduction as the port side areas.

  14. Use of GIS for Earthquakes in Brazil

    NASA Astrophysics Data System (ADS)

    Franca, G. S.; Algarte, K. T.; Assumpcao, M.; Barbosa, J. R.; Roig, H. L.; Pascual, M. F.; Vasconcelos, A. E.; Ferreira, J. M.; Ribotta, L. C.; do Nascimento, A. F.; Pavao, C. G.

    2011-12-01

    We present geoprocessing techniques to monitor and analyse earthquakes in Brazil. We constructed a georeferenced database called SIGSIBRA using PostgreSQL + PostGIS softwares, and fed by information from the SISBRA earthquake catalog, IBGE geographical data and CPRM geological data. The SISBRA catalog was built from the book "Sismicidade Brasileira" (Berrocal et al, 1984), updated with the Brazilian seismic bulletins from the Brazilian Geophysical Journal up to 1995, and especially with the data from seismographic monitoring activities of the University of Brasília-SIS/UnB, the Federal University of Rio Grande do Norte-UFRN, the University of Sao Paulo-USP and the Institute for Technological Research (IPT). Earthquakes occur in Brazil with moderate to low magnitudes. Besides natural earthquakes, seismic activity triggered by water dams must also be monitored. With the growing number and size of Brazilian dams (because of the many rivers, favorable topography and "clean" energy) concern with reservoir triggered seismicity is expected to increase. Approval for the construction of a hydropower plant requires seismic hazard assesmment prepared by an interdisciplinary team, with a large contribution of geoprocessing specialists. Therefore, it is important to study the characteristics of this seismicity, so that these professionals can avoid or mitigate potential environmental and social harm to communities on the margins of large dams. Thus the SIGSIBRA system can generate spatial analysis of its events, such as intensity estimation of "Kernel" points distribution; spatial statistics; spatial autocorrelation (Morans I) and correlations with geological structures, making it possible to characterize important aspects of the Brazilian seismicity. Finally, we show the statistical analysis of the database through the program ZMAP and estimate the intraplate seismogenic zones in Brazil.

  15. Dual Nature of Heat Flux in Stable Atmospheric Surface Layer

    NASA Astrophysics Data System (ADS)

    Srivastava, P.; Sharan, M.

    2015-12-01

    The behavior of heat flux (H) with respect to the stability parameter (ζ) in stable surface layer (SSL) is analyzed with in the framework of Monin-Obukhov similarity (MOS) theory. The analytical expressions of H are obtained as functions of wind speed (U) and wind shear (dU/dz) using the linear similarity functions and accordingly two cases, (i) U = δ (constant) and (ii) dU/dz = δ are considered. The mathematical analysis shows that the magnitude of H increases with ζ till it attains a maximum value at ζ =ζc and then starts decreasing with increasing stability suggesting the dual characteristic of heat flux with stability parameter. The point of maximum heat flux is found to be dependent on the roughness length (z0) as well as the height above the surface. An attempt has been made to analyze the sensitivity of this dual characteristic of H with ζ using the non-linear similarity functions. The analysis shows that the dual nature of H persists in the case of linear as well as non-linear similarity functions. However, the point of extremum appears to be dependent on the nature of the similarity functions. Turbulent data over a tropical site Ranchi (India) is analyzed to validate the observed nature of H with the theoretical nature as predicted by MOS. The analysis of observational data reveals the non-existence of any preferred stability state in SSL as speculated by Wang and Bras (2010, 2011) and supports the conclusions of Malhi 1995, Derbyshire 1999, van de Wiel et al. 2007, Basu et al. 2008, and van de Wiel et al. 2011. Thus, the non-uniqueness of MOS equations does not appear to be a mathematical artifact and it is consistent with the observations as far as the nature of heat flux with respect to stability parameter in SSL is concerned.

  16. La maladie de Hirayama: à propos de quatre observations tunisiennes et revue de la literature

    PubMed Central

    Amor, Sana Ben; Hassine, Anis; Chatti, Ines; Khefifi, Anissa; Doggui, Mohamed; Harzallah, Mohamed Salah; Benammou, Sofien

    2015-01-01

    Nous rapportons les aspects cliniques et électriques de la maladie de Hirayama en Tunisie à travers une série de quatre observations diagnostiquées au service de neurologie Sahloul. Il s'agit de quatre femmes. L’âge moyen était 30,25 ans avec des extrêmes de 27 et 37 ans. Une patiente avait un antécédent de traumatisme cervical, trois avaient une profession favorisant la position prolongée du rachis cervical en flexion. Un déficit moteur distal et une amyotrophie de la main et de l'avant bras droits d'installation progressive étaient observés dans tous les cas. Il n'avait ni des troubles sensitifs objectifs ni de modification des reflexes ostéotendineux et cutanés. L'EMG montrait une dénervation motrice dans le territoire des muscles dépendants des racines C7, C8, et D1. L'IRM cervicale était sans anomalie dans tous les cas. L’évolution était marquée par la bilatéralisation de la symptomatologie chez une patiente et une stabilisation clinique chez les autres. Ainsi, les aspects cliniques et électriques de la maladie de Hirayama dans cette série tunisienne sont comparables à ceux rapportés dans la littérature en dehors d'une atteinte strictement féminine. PMID:26185570

  17. Poussée de maladie de Kaposi et élévation du CA 19-9: penser à la tuberculose!

    PubMed Central

    Ajili, Faida; Hariz, Héla; Souissi, Asmahen; Abid, Rim; Boussetta, Najeh; Laabidi, Besma; Battikh, Riadh; Louzir, Bassem; Othmani, Salah

    2013-01-01

    La maladie de Kaposi (MK) est une entité pathologique qui peut survenir chez les patients VIH positifs et dans le cadre d'une immunodépression, d'origine tuberculeuse très rarement. On décrit le cas d'une MK chez un patient VIH négatif au décours d'une tuberculose. Nous rapportons le cas d'un patient âgé de 81 ans, VIH négatif, ayant présenté deux nodules angiomateux de l'avant bras gauche dont la biopsie cutanée était en faveur d'une MK. L’évolution était marquée 2 mois plus tard, par l'apparition de placards angiomateux extensifs des deux membres supérieurs et d'adénopathies cervicales jugulo-carotidiennes bilatérales. La biopsie ganglionnaire était en faveur d'une tuberculose ganglionnaire. Par ailleurs, il avait un taux sérique élevé des CA 19-9. La régression de l’étendue des lésions au niveau des membres supérieurs et la normalisation du taux sérique des CA 19-9 ont été obtenues sous traitement anti-tuberculeux. Chez les patients atteints d'une MK avec une élévation des CA 19-9, il faut penser à la tuberculose. PMID:24711871

  18. La prise en charge des morsures de chien chez les enfants

    PubMed Central

    Sabhaney, Vikram; Goldman, Ran D.

    2012-01-01

    Résumé Question Une fillette de 4 ans jouait avec le chien de ses voisins. Le chien s’est excité et a mordu la jeune fille à l’avant-bras, y laissant une plaie punctiforme. À cause cette blessure, elle s’est présentée à mon bureau. Devrais-je la traiter avec des antibiotiques? Quel antibiotique faut-il utiliser et pendant combien de temps? Réponse L’administration d’antibiotiques prophylactiques est indiquée lorsqu’on a procédé à une suture primitive de la morsure, que la plaie est de gravité modérée à sévère, qu’elle est punctiforme (particulièrement s’il y a eu pénétration de l’os, de la gaine tendineuse ou de l’articulation), pour les morsures au visage, aux mains, aux pieds ou aux parties génitales ou lorsque les victimes sont immunodéprimées ou souffrent d’asplénisme. L’antibiotique de première intention est l’amoxicilline-clavulanate. La prophylaxie appropriée antitétanique et contre la rage devrait faire partie des soins chez un patient qui a été mordu par un chien, tout comme le débridement local et le nettoyage complet de la plaie.

  19. Farmyard Manure and Fertilizer Effects on Seed Potato (Solanum tuberosum L.) Yield in Green House Production

    NASA Astrophysics Data System (ADS)

    László, M.

    2009-04-01

    Nowadays is widely well know that the potato is an important vegetable crop at Brazíl. It is grown on about 173.000 ha, with total yield of 2.6 million tons year-1. The average yield is 15 t ha-1. This level is very low because degeneration of crop is rapid under high temperature and high viruses pressure. Therefore seed potato propagation and production is principal on consumption potato production. This is why we found it necessary to develop it. The latossolo vermelho soil-farmyard manure- burnt rice straw-fertilizer 4N:14P:8K greenhouse pot trial was set up at the National Vegetable Crops Research Center, Brasília-DF, Brazíl in 1990. The methods of the experiments were soil x farmyard manure x burnt rice straw, soil x 4N:14P:8K fertilizer and soil x farmyard manure x burnt rice straw x 4N:14P:8K fertilizer on randomized block design in total 29 combination of treatments in 5, 5 and 3 repetitions with in a total parcel of 116. According to chemical analysis of the a., soil, b., farmyard manure and c., burnt rice straw the agrochemistry parameters were as follows (estimated datas): a., latossolo vermelho soil: CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1, b., farmyard manure: N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., burnt rice straw: N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. The experimental datas were estimated by analysis of variance, ANOVA and MANOVA. The main conclusions were as follows: 1. Mixture of 80% latossolo vermelho, 10% burnt rice straw and 10% farmyard manure were shown best performance on seed potato productivity. The piece of tubers with a 0-20 mm (consumption seeds) was increased by 77%. 2. Total seed potato number was reached maximum at 10.8 g pot-1 4N:14P:8K fertilizer regarding to average of treatments with a 33%. 3. Dry biomassa production plant-1 was decreased by high dose of 4N:14P:8K

  20. Reliability and validity of two versions of the upper extremity functional index.

    PubMed

    Chesworth, Bert M; Hamilton, Clayon B; Walton, David M; Benoit, Melissa; Blake, Tracy A; Bredy, Heather; Burns, Cameron; Chan, Lianne; Frey, Elizabeth; Gillies, Graham; Gravelle, Teresa; Ho, Rick; Holmes, Robert; Lavallée, Roland L J; MacKinnon, Melanie; Merchant, Alishah Jamal; Sherman, Tammy; Spears, Kelly; Yardley, Darryl

    2014-01-01

    Objectif : Étudier la fiabilité, la validité et la sensibilité au changement des versions à 20 questions et à 15 questions raffinées par Rasch de l'Indice fonctionnel des membres supérieurs (IFMS-20 et IFMS-15, respectivement) et déterminer l'effet du bras dominant sur la différence minimale positive cliniquement importante (pDMCI). Méthodes : Les adultes ayant une dysfonction des membres supérieurs (MS) ont répondu au questionnaire IFMS-20, aux questionnaires de l'Échelle fonctionnelle des membres supérieurs (EFMS), de l'Échelle de limitation de la douleur et de l'Échelle de l'intensité de la douleur au cours de leurs premières évaluations en physiothérapie (moment 1); de 24 à 48 heures plus tard (moment 2) et 3 semaines après le début du traitement ou le congé, selon l'échéance la plus rapprochée (moment 3). On a réuni des données démographiques, y compris sur leur état de travailleur, au cours du moment 1. Le physiothérapeute traitant et le patient ont fourni des évolutions globales du changement (EGC) au moment 3. On a calculé le résultat du questionnaire IFMS-15 à partir de questions pertinentes contenues dans la version IFMS-20. Le coefficient de corrélation intracatégorie (CCI) et le changement détectable minimal (CDM) ont quantifié la fiabilité de test–retest (moment 1–moment 2). La validité convergente transversale a été déterminée par le lien (r de Pearson) entre les mesures de fonction et de douleur prises au moment 1. On a évalué la validité des groupes connus au moyen d'une analyse bidirectionnelle des écarts (ANOVA) entre trois niveaux d'état de fonctionnement. La validité longitudinale a été déterminée en fonction du lien (r de Pearson) entre les scores de changement de la fonction et de la douleur (moment 1–moment 3). Des courbes des caractéristiques opérationnelles du récepteur (COR) ont estimé la pDMCI à partir des scores de changement entre le moment 1 et le moment 3 et les EGC

  1. A remarkable cranium of Plesiopithecus teras (Primates, Prosimii) from the Eocene of Egypt.

    PubMed Central

    Simons, E L; Rasmussen, D T

    1994-01-01

    Between 1991 and 1993 specimens of a highly distinctive primate, named Plesiopithecus teras [Simons, E.L. (1992) Proc. Natl. Acad. Sci. USA 89, 10743-10747], were found at site L-41 in late Eocene deposits of the Fayum Depression, Egypt. The most important of these specimens consists of a nearly complete skull, which facilitates the evaluation of affinities of this primate. Characteristics of the known material now demonstrate that Plesiopithecus is a prosimian, although mandibular molar morphology, in particular, bears similarity to that in molars of archaic members of Anthropoidea. Plesiopithecus has a postorbital bar but lacks postorbital closure, it has upper molars without hypocones, and it may retain four lower premolars. Its familial rank was considered incertae sedis by Simons [Simons, E.L. (1992) Proc. Natl. Acad. Sci. USA 89, 10743-10747]; it can now be demonstrated that Plesiopithecus justifies establishment of a new family and superfamily. The new superfamily apparently lies closer to the toothcomb prosimians (strepsirhines) than to any other known primate group. Under this interpretation the enlarged, procumbent tooth in the jaw of Plesiopithecus is homologous to either the lateral incisor or the canine of the prosimian toothcomb. Images PMID:7937923

  2. Endocytic uptake of nonenzymatically glycosylated proteins is mediated by a scavenger receptor for aldehyde-modified proteins.

    PubMed

    Takata, K; Horiuchi, S; Araki, N; Shiga, M; Saitoh, M; Morino, Y

    1988-10-15

    Long term incubation of proteins with glucose, named the Maillard reaction (Maillard, L. C. (1912) C. R. Acad. Sci. (Paris) 154, 66-68), gives rise to advanced glycosylation end product (AGE) with fluorescence, color, as well as cross-linked properties. The receptor-mediated endocytosis of AGE-proteins by macrophages was reported (Vlassara, H., Brownlee, M., and Cerami, A. (1985) Proc. Natl. Acad. Sci. U.S.A. 82, 5588-5592). The present study on the binding of AGE-bovine serum albumin (BSA) to rat peritoneal macrophages and sinusoidal liver cells demonstrated the presence of a saturable, high affinity receptor for AGE-BSA with Kd = 2.4 x 10(-7) M (macrophages) and 2.1 x 10(-7) M (sinusoidal cells). The cellular binding of AGE-BSA and its endocytic uptake by these cells were competitively inhibited by BSA preparations modified with aliphatic aldehydes such as formaldehyde or glycolaldehyde, ligands known to be specific for a scavenger receptor for aldehyde-modified proteins (Horiuchi, S., Murakami, M., Takata, K., and Morino, Y. (1986). J. Biol. Chem. 261, 4962-4966). These ligands also had a profound in vivo effect on the plasma clearance of 125I-AGE-BSA as well as its hepatic uptake. Thus, endocytic uptake of AGE-proteins by macrophages appeared to be mediated by a scavenger receptor for aldehyde-modified proteins. This provides evidence for the biological importance of the scavenger receptor in eliminating senescent macromolecules from the circulation.

  3. Neandertal nasal structures and upper respiratory tract “specialization”

    PubMed Central

    Franciscus, Robert G.

    1999-01-01

    Schwartz and Tattersall [Schwartz, J. H. & Tattersall, I. (1996) Proc. Natl. Acad. Sci. USA 93, 10852–10854] have argued for a previously unrecognized suite of autapomorphies in the internal nasal region of Neandertals that make them unique, not only among hominids, but possibly among all other terrestrial mammals. These purported autapomorphies include (i) the development of an internal nasal margin bearing a well developed and vertically oriented medial projection; (ii) a pronounced medial swelling of the lateral nasal wall into the posterior nasal cavity; and (iii) the lack of an ossified roof over the lacrimal groove. In addition, Laitman et al. [Laitman, J. T., Reidenberg, J. S., Marquez, S. & Gannon, P. J. (1996) Proc. Natl. Acad. Sci. USA 93, 10543–10545] pointed to these features as evidence for upper respiratory tract specializations among the Neandertals, indicating potential differences in behavior compared with modern humans. Critically reviewing the anatomical basis for Schwartz and Tattersall’s contentions reveals several serious problems with their analysis, including (i) reliance on specimens with damaged, incomplete, or, in some cases, entirely absent relevant anatomy; (ii) failure to consider primary vs. secondary spatial consequences in nasal trait conceptualization; and (iii) failure to consider actual ranges of variation in these traits in both fossil and recent humans. Accordingly, the unique phylogenetic and adaptive “specializations” attributed to Neandertal internal nasal structures are unwarranted. PMID:9990106

  4. Magnetic Tests For Magnetosome Chains In Martian Meteorite ALH84001

    NASA Astrophysics Data System (ADS)

    Weiss, B. P.; Kim, S.; Kirschvink, J. L.; Sankaran, M.; Kobayashi, A.; Komeili, A.

    2003-12-01

    Transmission electron microscopy studies have been used to argue that magnetites in carbonates from Martian meteorite ALH84001 have a composition and morphology indistinguishable from that of magnetotactic bacteria and their magnetofossils (1). It has even been claimed from scanning electron microscopy imaging that some ALH84001 magnetites are aligned in chains (2). If true, this would provide dramatic support for the magnetofossil hypothesis because alignment in chains is perhaps the most distinctive of the six crystallographic properties thought to be collectively unique to magnetosomes. The leading alternative hypothesis is that the ALH84001 magnetites are the inorganic products of shock-heating of the carbonates (3, 4). Here we use three rock magnetic techniques-low-temperature cycling, the Moskowitz test (5), and ferromagnetic resonance (FMR)-to demonstrate that most or all of the magnetites in ALH84001 are unusually pure and fine-grained but are not arranged in magnetosome chains. 1. K. L. Thomas-Keprta et al., Geochim. Cosmochim. Acta 64, 4049-4081 (2000). 2. I. E. Friedmann, J. Wierzchos, C. Ascaso, M. Winklhofer, Proc. Natl. Acad. Sci. USA 98, 2176-2181 (2001). 3. D. C. Golden et al., Am. Mineral. 83, 370-375 (2001). 4. D. J. Barber, E. R. D. Scott, Proc. Natl. Acad. Sci. USA 99, 6556-6561 (2002). 5. B. M. Moskowitz, R. B. Frankel, D. A. Bazylinski, Earth Planet. Sci. Lett. 120, 283-300 (1993).

  5. Le Carbonifère du Maroc central : les formations de Migoumess, de Tirhela et d'Idmarrach. Lithologie, biostratigraphie et conséquences géodynamiquesThe Carboniferous formations of Migoumess, Tirhela and Idmarrach (central Morocco): lithology, biostratigraphy and geodynamic consequences

    NASA Astrophysics Data System (ADS)

    Berkhli, Mostafa; Vachard, Daniel

    2002-01-01

    New biostratigraphical data based on foraminifers, algae and pseudo-algae indicate that the limestone pebbles of the channelized polygenic conglomerates of the Migoumess formation contain Late Visean (V3b γ-V3c) assemblages. That confirms the Westphalian age attributed to this formation by Hollard [Zdt. Geol. Ges. 129 (1978) 495-512]. The Tournaisian age assigned to it by palynology [C. R. Acad. Sci. Paris, série II 310 (1990) 1573-1576] cannot be retained. The Tirhela formation, Late Visean and Serpukhovian (E1) in age, is coeval with the Akerchi formation [Berkhli, thèse d'État, 1999; Berkhli et al., J. Afr. Earth Sci. (accepté)]. The Idmarrach formation, mapped as a thrust sheet [C. R. Acad. Sci. Paris, série II 310 (1990) 1573-1576], is dated as Serpukhovian (E1) and its thrusting is consequently post-Serpukhovian. Palaeogeographic and geodynamic consequences are listed. To cite this article: M. Berkhli, D. Vachard, C. R. Geoscience 334 (2002) 67-72

  6. Edge ratio and community structure in networks

    NASA Astrophysics Data System (ADS)

    Cafieri, Sonia; Hansen, Pierre; Liberti, Leo

    2010-02-01

    A hierarchical divisive algorithm is proposed for identifying communities in complex networks. To that effect, the definition of community in the weak sense of Radicchi [Proc. Natl. Acad. Sci. U.S.A. 101, 2658 (2004)] is extended into a criterion for a bipartition to be optimal: one seeks to maximize the minimum for both classes of the bipartition of the ratio of inner edges to cut edges. A mathematical program is used within a dichotomous search to do this in an optimal way for each bipartition. This includes an exact solution of the problem of detecting indivisible communities. The resulting hierarchical divisive algorithm is compared with exact modularity maximization on both artificial and real world data sets. For two problems of the former kind optimal solutions are found; for five problems of the latter kind the edge ratio algorithm always appears to be competitive. Moreover, it provides additional information in several cases, notably through the use of the dendrogram summarizing the resolution. Finally, both algorithms are compared on reduced versions of the data sets of Girvan and Newman [Proc. Natl. Acad. Sci. U.S.A. 99, 7821 (2002)] and of Lancichinetti [Phys. Rev. E 78, 046110 (2008)]. Results for these instances appear to be comparable.

  7. Reexamination of magnetic isotope and field effects on adenosine triphosphate production by creatine kinase

    PubMed Central

    Crotty, Darragh; Silkstone, Gary; Poddar, Soumya; Ranson, Richard; Prina-Mello, Adriele; Wilson, Michael T.; Coey, J. M. D.

    2012-01-01

    The influence of isotopically enriched magnesium on the creatine kinase catalyzed phosphorylation of adenosine diphosphate is examined in two independent series of experiments where adenosine triphosphate (ATP) concentrations were determined by a luciferase-linked luminescence end-point assay or a real-time spectrophotometric assay. No increase was observed between the rates of ATP production with natural Mg, 24Mg, and 25Mg, nor was any significant magnetic field effect observed in magnetic fields from 3 to 1,000 mT. Our results are in conflict with those reported by Buchachenko et al. [J Am Chem Soc 130:12868–12869 (2008)], and they challenge these authors’ general claims that a large (two- to threefold) magnetic isotope effect is “universally observable” for ATP-producing enzymes [Her Russ Acad Sci 80:22–28 (2010)] and that “enzymatic phosphorylation is an ion-radical, electron-spin-selective process” [Proc Natl Acad Sci USA 101:10793–10796 (2005)]. PMID:22198842

  8. Accurate force spectroscopy in tapping mode atomic force microscopy in liquids

    NASA Astrophysics Data System (ADS)

    Xu, Xin; Melcher, John; Raman, Arvind

    2010-01-01

    Existing force spectroscopy methods in tapping mode atomic force microscopy (AFM) such as higher harmonic inversion [M. Stark, R. W. Stark, W. M. Heckl, and R. Guckenberger, Proc. Natl. Acad. Sci. U.S.A. 99, 8473 (2002)] or scanning probe acceleration microscopy [J. Legleiter, M. Park, B. Cusick, and T. Kowalewski, Proc. Natl. Acad. Sci. U.S.A. 103, 4813 (2006)] or integral relations [M. Lee and W. Jhe, Phys. Rev. Lett. 97, 036104 (2006); S. Hu and A. Raman, Nanotechnology 19, 375704 (2008); H. Hölscher, Appl. Phys. Lett. 89, 123109 (2006); A. J. Katan, Nanotechnology 20, 165703 (2009)] require and assume as an observable the tip dynamics in a single eigenmode of the oscillating microcantilever. We demonstrate that this assumption can distort significantly the extracted tip-sample interaction forces when applied to tapping mode AFM with soft cantilevers in liquid environments. This exception is due to the fact that under these conditions the second eigenmode is momentarily excited and the observed tip dynamics clearly contains contributions from the fundamental and second eigenmodes. To alleviate this problem, a simple experimental method is proposed to screen the second eigenmode contributions in the observed tip deflection signal to allow accurate tip-sample force reconstruction in liquids. The method is implemented experimentally to reconstruct interaction forces on polymer, bacteriorhodopsin membrane, and mica samples in buffer solutions.

  9. Pierre-Joseph Macquer an eighteenth-century artisanal-scientific expert.

    PubMed

    Lehman, Christine

    2012-07-01

    Pierre-Joseph Macquer (1718-1784) is well known as one of the major chemists in the eighteenth century as a theoretician and a teacher. He is also known for his works on dyeing. This paper presents a new face of Macquer. He proposed a theory on mordants in dyeing as early as 1775. Besides his activity at the Académie des sciences, he played an important role in Government as the commissioner of dyeing from 1766 where he established close links with artisan inventors. Académicien chimiste at the royal Manufactory of Sèvres from 1757, he was also the inventor of French porcelain. His notebooks show his organization, method, courage, passion and obstinacy in the search for the paste for hard porcelain. He also proposed an interpretation of its formation. Macquer was both a theoretician and a practical expert in dyeing as well as in porcelain making. He managed to bridge the gap between science and art.

  10. Viscosity Solutions for the One-Body Liouville Equation in Yang-Mills Charged Bianchi Models with Non-Zero Mass

    NASA Astrophysics Data System (ADS)

    Ayissi, Raoul Domingo; Noutchegueme, Norbert; Etoua, Remy Magloire; Tchagna, Hugues Paulin Mbeutcha

    2015-09-01

    Recently in 2005, Briani and Rampazzo (Nonlinear Differ Equ Appl 12:71-91, 2005) gave, using results of Crandall and Lions (Ill J Math 31:665-688, 1987), Ishii (Indiana Univ Math J 33: 721-748, 1984, Bull Fac Sci Eng 28: 33-77, 1985) and Ley (Adv Diff Equ 6:547-576, 2001) a density approach to Hamilton-Jacobi equations with t-measurable Hamiltonians. In this paper we show, using an important result of Briani and Rampazzo (Nonlinear Differ Equ Appl 12:71-91, 2005) the existence and uniqueness of viscosity solutions to the one-body Liouville relativistic equation in Yang-Mills charged Bianchi space times with non-zero mass. To our knowledge, the method used here is original and thus, totally different from those used in Alves (C R Acad Sci Paris Sér A 278:1151-1154, 1975), Choquet-Bruhat and Noutchegueme (C R Acad Sci Paris Sér I 311, 1973), Choquet-Bruhat and Noutchegueme (Ann Inst Henri Poincaré 55:759-787, 1991), Choquet-Bruhat and Noutchegueme (Pitman Res Notes Math Ser 253:52-71, 1992), Noutchegueme and Noundjeu (Ann Inst Henri Poincaré 1:385-404, 2000), Wollman (J Math Anal Appl 127:103-121, 1987) and Choquet-Bruhat (Existence and uniqueness for the Einstein-Maxwell-Liouville system. Volume dedicated to Petrov, Moscow, 1971) who have studied the same equation.

  11. Adult pallium transcriptomes surprise in not reflecting predicted homologies across diverse chicken and mouse pallial sectors

    PubMed Central

    Belgard, T. Grant; Montiel, Juan F.; Wang, Wei Zhi; García-Moreno, Fernando; Ponting, Chris P.; Molnár, Zoltán

    2013-01-01

    The thorniest problem in comparative neurobiology is the identification of the particular brain region of birds and reptiles that corresponds to the mammalian neocortex [Butler AB, Reiner A, Karten HJ (2011) Ann N Y Acad Sci 1225:14–27; Wang Y, Brzozowska-Prechtl A, Karten HJ (2010) Proc Natl Acad Sci USA 107(28):12676–12681]. We explored which genes are actively transcribed in the regions of controversial ancestry in a representative bird (chicken) and mammal (mouse) at adult stages. We conducted four analyses comparing the expression patterns of their 5,130 most highly expressed one-to-one orthologous genes that considered global patterns of expression specificity, strong gene markers, and coexpression networks. Our study demonstrates transcriptomic divergence, plausible convergence, and, in two exceptional cases, conservation between specialized avian and mammalian telencephalic regions. This large-scale study potentially resolves the complex relationship between developmental homology and functional characteristics on the molecular level and settles long-standing evolutionary debates. PMID:23878249

  12. Methane concentrations in water wells unrelated to proximity to existing oil and gas wells in northeastern Pennsylvania.

    PubMed

    Siegel, Donald I; Azzolina, Nicholas A; Smith, Bert J; Perry, A Elizabeth; Bothun, Rikka L

    2015-04-01

    Recent studies in northeastern Pennsylvania report higher concentrations of dissolved methane in domestic water wells associated with proximity to nearby gas-producing wells [ Osborn et al. Proc. Natl. Acad. Sci. U. S. A. 2011 , 108 , 8172 ] and [ Jackson et al. Proc. Natl. Acad. Sci. U. S. A. , 2013 , 110 , 11250 ]. We test this possible association by using Chesapeake Energy's baseline data set of over 11,300 dissolved methane analyses from domestic water wells, densely arrayed in Bradford and nearby counties (Pennsylvania), and near 661 pre-existing oil and gas wells. The majority of these, 92%, were unconventional wells, drilled with horizontal legs and hydraulically fractured. Our data set is hundreds of times larger than data sets used in prior studies. In contrast to prior findings, we found no statistically significant relationship between dissolved methane concentrations in groundwater from domestic water wells and proximity to pre-existing oil or gas wells. Previous analyses used small sample sets compared to the population of domestic wells available, which may explain the difference in prior findings compared to ours.

  13. A geometric approach to the synchronization of a pair of two-state switching rowers interacting hydrodynamically

    NASA Astrophysics Data System (ADS)

    Leoni, M.

    2012-10-01

    Two-state switching rowers, or simply rowers, are model self-sustained oscillators in a fluid at a low Reynolds number, introduced in Cosentino Lagomarsino et al (2003 Phys. Rev. E 68 021908) and realized experimentally in Kotar et al (2010 Proc. Natl Acad. Sci. USA 107 7669-73). Here we present a new approach for investigating the hydrodynamic synchronization of a pair of rowers with the same and different frequencies. Our analysis is geometrical, in the spirit of the qualitative theory of dynamical systems. By taking advantage of the separation of timescales in the model, the dynamics can be decomposed into a sequence of fast changes followed by slow relaxations. In this framework we discuss how synchronization is determined by the dominant mode of the relaxation dynamics. For rowers with the same frequencies, our analysis recovers naturally the anti-phase synchronized motion, its stability and the basin of attraction (Cosentino Lagomarsino et al 2003 Phys. Rev. E 68 021908; Kotar et al 2010 Proc. Natl Acad. Sci. USA 107 7669-73) in the case of rowers with different frequencies we are able to provide upper bounds for the phase-locked solution and to determine a critical value of the frequency mismatch after which the coordination is lost. Our estimates are in good agreement with numerical simulations. In this way we provide a simple and robust explanation for the transition from the phase-locked state to the loss of synchrony.

  14. Boolean networks with veto functions

    NASA Astrophysics Data System (ADS)

    Ebadi, Haleh; Klemm, Konstantin

    2014-08-01

    Boolean networks are discrete dynamical systems for modeling regulation and signaling in living cells. We investigate a particular class of Boolean functions with inhibiting inputs exerting a veto (forced zero) on the output. We give analytical expressions for the sensitivity of these functions and provide evidence for their role in natural systems. In an intracellular signal transduction network [Helikar et al., Proc. Natl. Acad. Sci. USA 105, 1913 (2008), 10.1073/pnas.0705088105], the functions with veto are over-represented by a factor exceeding the over-representation of threshold functions and canalyzing functions in the same system. In Boolean networks for control of the yeast cell cycle [Li et al., Proc. Natl. Acad. Sci. USA 101, 4781 (2004), 10.1073/pnas.0305937101; Davidich et al., PLoS ONE 3, e1672 (2008), 10.1371/journal.pone.0001672], no or minimal changes to the wiring diagrams are necessary to formulate their dynamics in terms of the veto functions introduced here.

  15. General topology meets model theory, on p and t.

    PubMed

    Malliaris, Maryanthe; Shelah, Saharon

    2013-08-13

    Cantor proved in 1874 [Cantor G (1874) J Reine Angew Math 77:258-262] that the continuum is uncountable, and Hilbert's first problem asks whether it is the smallest uncountable cardinal. A program arose to study cardinal invariants of the continuum, which measure the size of the continuum in various ways. By Gödel [Gödel K (1939) Proc Natl Acad Sci USA 25(4):220-224] and Cohen [Cohen P (1963) Proc Natl Acad Sci USA 50(6):1143-1148], Hilbert's first problem is independent of ZFC (Zermelo-Fraenkel set theory with the axiom of choice). Much work both before and since has been done on inequalities between these cardinal invariants, but some basic questions have remained open despite Cohen's introduction of forcing. The oldest and perhaps most famous of these is whether " p = t," which was proved in a special case by Rothberger [Rothberger F (1948) Fund Math 35:29-46], building on Hausdorff [Hausdorff (1936) Fund Math 26:241-255]. In this paper we explain how our work on the structure of Keisler's order, a large-scale classification problem in model theory, led to the solution of this problem in ZFC as well as of an a priori unrelated open question in model theory.

  16. Advanced Communications Architecture Demonstration Made Significant Progress

    NASA Technical Reports Server (NTRS)

    Carek, David Andrew

    2004-01-01

    Simulation for a ground station located at 44.5 deg latitude. The Advanced Communications Architecture Demonstration (ACAD) is a concept architecture to provide high-rate Ka-band (27-GHz) direct-to-ground delivery of payload data from the International Space Station. This new concept in delivering data from the space station targets scientific experiments that buffer data onboard. The concept design provides a method to augment the current downlink capability through the Tracking Data Relay Satellite System (TDRSS) Ku-band (15-GHz) communications system. The ACAD concept pushes the limits of technology in high-rate data communications for space-qualified systems. Research activities are ongoing in examining the various aspects of high-rate communications systems including: (1) link budget parametric analyses, (2) antenna configuration trade studies, (3) orbital simulations (see the preceding figure), (4) optimization of ground station contact time (see the following graph), (5) processor and storage architecture definition, and (6) protocol evaluations and dependencies.

  17. Pierre Ambroise-Thomas: a loyal friend and a strong supporter of tropical medicine in Brazil.

    PubMed

    Daniel-Ribeiro, Cláudio Tadeu

    2016-01-01

    Our colleagues at the Sociedade Brasileira de Medicina Tropical have been informed of the demise of Professor Pierre Ambroise-Thomas (1937-2014). However, considering that the tribute we paid to him in 2015 - at the 20th anniversary of the Seminário Laveran & Deane sobre Malária - is equally true today, it is worth sharing it with the readers of the RSBMT, in recognition of his many virtues. Pierre Ambroise-Thomas (MD in 1963 and DSc in 1969) was Honorary Professor of Parasitology and Tropical Medicine at the Faculté de Médecine de Grenoble (France), Honorary President of the Académie Nationale de Médecine, member of the Académie Nationale de Pharmacie and Officier dans l'Ordre de La Légion d'Honneur. In addition to his important contributions to tropical medicine and parasitology, working in France during his long and productive career (50 years and 300 publications), Ambroise-Thomas became an admirer and supporter of Brazilian activities related to research, teaching and information in Tropical Medicine.

  18. Adult pallium transcriptomes surprise in not reflecting predicted homologies across diverse chicken and mouse pallial sectors.

    PubMed

    Belgard, T Grant; Montiel, Juan F; Wang, Wei Zhi; García-Moreno, Fernando; Margulies, Elliott H; Ponting, Chris P; Molnár, Zoltán

    2013-08-01

    The thorniest problem in comparative neurobiology is the identification of the particular brain region of birds and reptiles that corresponds to the mammalian neocortex [Butler AB, Reiner A, Karten HJ (2011) Ann N Y Acad Sci 1225:14-27; Wang Y, Brzozowska-Prechtl A, Karten HJ (2010) Proc Natl Acad Sci USA 107(28):12676-12681]. We explored which genes are actively transcribed in the regions of controversial ancestry in a representative bird (chicken) and mammal (mouse) at adult stages. We conducted four analyses comparing the expression patterns of their 5,130 most highly expressed one-to-one orthologous genes that considered global patterns of expression specificity, strong gene markers, and coexpression networks. Our study demonstrates transcriptomic divergence, plausible convergence, and, in two exceptional cases, conservation between specialized avian and mammalian telencephalic regions. This large-scale study potentially resolves the complex relationship between developmental homology and functional characteristics on the molecular level and settles long-standing evolutionary debates.

  19. Tendências De Teses e Dissertações Sobre Educação em Astronomia No Brasil

    NASA Astrophysics Data System (ADS)

    Bretones, Paulo Sergio; Megid Neto, Jorge

    2005-07-01

    Apresentam-se os resultados de uma pesquisa do tipo estado da arte sobre teses e dissertações defendidas no Brasil e relativas ao ensino de Astronomia, com objetivo de identificar essa produção e conhecer as principais tendências da pesquisa nesse campo. Foram localizadas 13 dissertações de mestrado e 3 teses de doutorado, as quais foram estudadas em função dos seguintes aspectos: isntituição, ano de defesa, nível escolar abrangido no estudo, foco temático do estudo e gênero de trabalho acadêmico. Pretende-se assim colaborar com a divulgação ampla da produção acadêmica na área. Ao mesmo tempo o estudo possibilita, a partir de investigações decorrentes, apontar as contribuições dessa produção para o ensino e sinalizar com necessidades a serem supridas por futuras pesquisas.

  20. Return of the living dead: Re-reading Pierre Flourens' contributions to neurophysiology and literature.

    PubMed

    Levinson, Sharman

    2013-01-01

    Historians of neurophysiology remember Marie Jean Pierre Flourens (1794-1867) for his experimental approach to nineteenth-century debates on cortical localization and, in particular, for his successful attacks on Frantz Joseph Gall's (1758-1828) phrenology (Gall and Spurzheim, 1810-19). Whereas Gall and his colleague, Johann Gaspar Spurzheim (1776-1832), posited correlations between features of the skull and brain development and claimed to have localized character traits, competencies and temperaments in specific cortical regions, Flourens advocated cerebral equipotentiality and provided empirical as well as philosophical grounds for his theories. Flourens has also been recognized for his contributions to the understanding of the cerebellum's role in the coordination of movement, the localization of a respiratory center in the medulla oblongata, the relationship between the semicircular canals and balance, the role of the periosteum in bone growth and regeneration, and finally, the anesthetic properties of chloroform. Less known to historians of neuroscience is the fact that Pierre Flourens was not only a neurophysiologist and Secrétaire Perpetuel of the French Académie des Sciences, he was also a member of the Académie Française, France's most prestigious literary academy. Examining Flourens' contributions as a writer and, at the same time, a prime target for criticism and caricature from journalists, yields a particularly interesting example of the problematic relations between different genres of science writing and their respective publics in mid-nineteenth-century France.

  1. Acadia National Park Climate Change Scenario Planning Workshop summary

    USGS Publications Warehouse

    Star, Jonathan; Fisichelli, Nicholas; Bryan, Alexander; Babson, Amanda; Cole-Will, Rebecca; Miller-Rushing, Abraham J.

    2016-01-01

    This report summarizes outcomes from a two-day scenario planning workshop for Acadia National Park, Maine (ACAD). The primary objective of the workshop was to help ACAD senior leadership make management and planning decisions based on up-to-date climate science and assessments of future uncertainty. The workshop was also designed as a training program, helping build participants' capabilities to develop and use scenarios. The details of the workshop are given in later sections. The climate scenarios presented here are based on published global climate model output. The scenario implications for resources and management decisions are based on expert knowledge distilled through scientist-manager interaction during workgroup break-out sessions at the workshop. Thus, the descriptions below are from these small-group discussions in a workshop setting and should not be taken as vetted research statements of responses to the climate scenarios, but rather as insights and examinations of possible futures (Martin et al. 2011, McBride et al. 2012).

  2. Methane concentrations in water wells unrelated to proximity to existing oil and gas wells in northeastern Pennsylvania.

    PubMed

    Siegel, Donald I; Azzolina, Nicholas A; Smith, Bert J; Perry, A Elizabeth; Bothun, Rikka L

    2015-04-01

    Recent studies in northeastern Pennsylvania report higher concentrations of dissolved methane in domestic water wells associated with proximity to nearby gas-producing wells [ Osborn et al. Proc. Natl. Acad. Sci. U. S. A. 2011 , 108 , 8172 ] and [ Jackson et al. Proc. Natl. Acad. Sci. U. S. A. , 2013 , 110 , 11250 ]. We test this possible association by using Chesapeake Energy's baseline data set of over 11,300 dissolved methane analyses from domestic water wells, densely arrayed in Bradford and nearby counties (Pennsylvania), and near 661 pre-existing oil and gas wells. The majority of these, 92%, were unconventional wells, drilled with horizontal legs and hydraulically fractured. Our data set is hundreds of times larger than data sets used in prior studies. In contrast to prior findings, we found no statistically significant relationship between dissolved methane concentrations in groundwater from domestic water wells and proximity to pre-existing oil or gas wells. Previous analyses used small sample sets compared to the population of domestic wells available, which may explain the difference in prior findings compared to ours. PMID:25764141

  3. Pierre Ambroise-Thomas: a loyal friend and a strong supporter of tropical medicine in Brazil.

    PubMed

    Daniel-Ribeiro, Cláudio Tadeu

    2016-01-01

    Our colleagues at the Sociedade Brasileira de Medicina Tropical have been informed of the demise of Professor Pierre Ambroise-Thomas (1937-2014). However, considering that the tribute we paid to him in 2015 - at the 20th anniversary of the Seminário Laveran & Deane sobre Malária - is equally true today, it is worth sharing it with the readers of the RSBMT, in recognition of his many virtues. Pierre Ambroise-Thomas (MD in 1963 and DSc in 1969) was Honorary Professor of Parasitology and Tropical Medicine at the Faculté de Médecine de Grenoble (France), Honorary President of the Académie Nationale de Médecine, member of the Académie Nationale de Pharmacie and Officier dans l'Ordre de La Légion d'Honneur. In addition to his important contributions to tropical medicine and parasitology, working in France during his long and productive career (50 years and 300 publications), Ambroise-Thomas became an admirer and supporter of Brazilian activities related to research, teaching and information in Tropical Medicine. PMID:27598625

  4. Ancestral major histocompatibility complex DRB genes beget conserved patterns of localized polymorphisms.

    PubMed Central

    Gaur, L K; Nepom, G T

    1996-01-01

    Genes within the major histocompatibility complex (MHC) are characterized by extensive polymorphism within species and also by a remarkable conservation of contemporary human allelic sequences in evolutionarily distant primates. Mechanisms proposed to account for strict nucleotide conservation in the context of highly variable genes include the suggestion that intergenic exchange generates repeated sets of MHC DRB polymorphisms [Gyllensten, U. B., Sundvall, M. & Erlich, H. A. (1991) Proc. Natl. Acad. Sci. USA 88, 3686-3690; Lundberg, A. S. & McDevitt, H. 0. (1992) Proc. Natl. Acad. Sci. USA 89, 6545-6549]. We analyzed over 50 primate MHC DRB sequences, and identified nucleotide elements within macaque and baboon DRB6-like sequences with deletions corresponding to specific exon 2 hypervariable regions, which encode a discrete alpha helical segment of the MHC antigen combining site. This precisely localized deletion provides direct evidence implicating segmental exchange of MHC-encoded DRB gene fragments as one of the evolutionary mechanisms both generating and maintaining MHC diversity. Intergenic exchange at this site may be fundamental to the diversification of immune protection in populations by permitting alteration in the specificity of the MHC that determines the repertoire of antigens bound. Images Fig. 2 PMID:8643583

  5. [Louis XIV's Ginseng: Shaping of Knowledge on an Herbal Medicine in the Late 17th and the Early 18th Century France].

    PubMed

    Lee, Hye-Min

    2016-04-01

    This article aims to investigate the shaping of knowledge and discourse on ginseng, especially among physicians and botanists, since its introduction to France from the 17th century until the early 18th century. In France, knowledge on herbal medicine, including that of ginseng, was shaped under the influence of the modern state's policy and institution: mercantilism and the Académie royale des sciences. The knowledge of herbal medicine developed as an important part of the mercantilist policy supported systematically by the Académie. The East Asian ginseng, renowned as a panacea, was first introduced into France in the 17th century, initially in a roundabout way through transportation and English and Dutch publications of travel tales from various foreign countries. The publication activity was mainly conducted by Thévenot company with the intention to meet the needs of French mercantilism promoted by Colbert. It also implied interests on medicine in order to bolster the people's health. The Thévenot company's activity thus offered vital information on plants and herbs abroad, one of which was ginseng. Furthermore, with Louis XIV's dispatching of the Jesuit missionaries to East Asia, the Frenchmen were able to directly gather information on ginseng. These information became a basis for research of the Académie. In the Académie, founded in 1666 by Colbert, the king's physicians and botanists systematically and collectively studied on exotic plants and medical herbs including ginseng. They were also key figures of the Jardin du Roi. These institutions bore a striking contrast to the faculty of medicine at the University of Paris which has been a center of the traditional Galenic medicine. The research of the Académie on ginseng was greatly advanced, owing much to the reports and samples sent from China and Canada by Jartoux, Sarrazin, and Lapitau. From the early 18th century, the conservative attitude of the University of Paris, which was a stronghold of

  6. [Louis XIV's Ginseng: Shaping of Knowledge on an Herbal Medicine in the Late 17th and the Early 18th Century France].

    PubMed

    Lee, Hye-Min

    2016-04-01

    This article aims to investigate the shaping of knowledge and discourse on ginseng, especially among physicians and botanists, since its introduction to France from the 17th century until the early 18th century. In France, knowledge on herbal medicine, including that of ginseng, was shaped under the influence of the modern state's policy and institution: mercantilism and the Académie royale des sciences. The knowledge of herbal medicine developed as an important part of the mercantilist policy supported systematically by the Académie. The East Asian ginseng, renowned as a panacea, was first introduced into France in the 17th century, initially in a roundabout way through transportation and English and Dutch publications of travel tales from various foreign countries. The publication activity was mainly conducted by Thévenot company with the intention to meet the needs of French mercantilism promoted by Colbert. It also implied interests on medicine in order to bolster the people's health. The Thévenot company's activity thus offered vital information on plants and herbs abroad, one of which was ginseng. Furthermore, with Louis XIV's dispatching of the Jesuit missionaries to East Asia, the Frenchmen were able to directly gather information on ginseng. These information became a basis for research of the Académie. In the Académie, founded in 1666 by Colbert, the king's physicians and botanists systematically and collectively studied on exotic plants and medical herbs including ginseng. They were also key figures of the Jardin du Roi. These institutions bore a striking contrast to the faculty of medicine at the University of Paris which has been a center of the traditional Galenic medicine. The research of the Académie on ginseng was greatly advanced, owing much to the reports and samples sent from China and Canada by Jartoux, Sarrazin, and Lapitau. From the early 18th century, the conservative attitude of the University of Paris, which was a stronghold of

  7. Active compensation of aperture discontinuities for WFIRST-AFTA: analytical and numerical comparison of propagation methods and preliminary results with a WFIRST-AFTA-like pupil

    NASA Astrophysics Data System (ADS)

    Mazoyer, Johan; Pueyo, Laurent; Norman, Colin; N'Diaye, Mamadou; van der Marel, Roeland P.; Soummer, Rémi

    2016-03-01

    The new frontier in the quest for the highest contrast levels in the focal plane of a coronagraph is now the correction of the large diffraction artifacts introduced at the science camera by apertures of increasing complexity. Indeed, the future generation of space- and ground-based coronagraphic instruments will be mounted on on-axis and/or segmented telescopes; the design of coronagraphic instruments for such observatories is currently a domain undergoing rapid progress. One approach consists of using two sequential deformable mirrors (DMs) to correct for aberrations introduced by secondary mirror structures and segmentation of the primary mirror. The coronagraph for the WFIRST-AFTA mission will be the first of such instruments in space with a two-DM wavefront control system. Regardless of the control algorithm for these multiple DMs, they will have to rely on quick and accurate simulation of the propagation effects introduced by the out-of-pupil surface. In the first part of this paper, we present the analytical description of the different approximations to simulate these propagation effects. In Appendix A, we prove analytically that in the special case of surfaces inducing a converging beam, the Fresnel method yields high fidelity for simulations of these effects. We provide numerical simulations showing this effect. In the second part, we use these tools in the framework of the active compensation of aperture discontinuities (ACAD) technique applied to pupil geometries similar to WFIRST-AFTA. We present these simulations in the context of the optical layout of the high-contrast imager for complex aperture telescopes, which will test ACAD on a optical bench. The results of this analysis show that using the ACAD method, an apodized pupil Lyot coronagraph, and the performance of our current DMs, we are able to obtain, in numerical simulations, a dark hole with a WFIRST-AFTA-like. Our numerical simulation shows that we can obtain contrast better than 2×10-9 in

  8. Unraveling Cholesterol Catabolism in Mycobacterium tuberculosis: ChsE4-ChsE5 α2β2 Acyl-CoA Dehydrogenase Initiates β-Oxidation of 3-Oxo-cholest-4-en-26-oyl CoA

    PubMed Central

    2016-01-01

    The metabolism of host cholesterol by Mycobacterium tuberculosis (Mtb) is an important factor for both its virulence and pathogenesis, although how and why cholesterol metabolism is required is not fully understood. Mtb uses a unique set of catabolic enzymes that are homologous to those required for classical β-oxidation of fatty acids but are specific for steroid-derived substrates. Here, we identify and assign the substrate specificities of two of these enzymes, ChsE4-ChsE5 (Rv3504-Rv3505) and ChsE3 (Rv3573c), that carry out cholesterol side chain oxidation in Mtb. Steady-state assays demonstrate that ChsE4-ChsE5 preferentially catalyzes the oxidation of 3-oxo-cholest-4-en-26-oyl CoA in the first cycle of cholesterol side chain β-oxidation that ultimately yields propionyl-CoA, whereas ChsE3 specifically catalyzes the oxidation of 3-oxo-chol-4-en-24-oyl CoA in the second cycle of β-oxidation that generates acetyl-CoA. However, ChsE4-ChsE5 can catalyze the oxidation of 3-oxo-chol-4-en-24-oyl CoA as well as 3-oxo-4-pregnene-20-carboxyl-CoA. The functional redundancy of ChsE4-ChsE5 explains the in vivo phenotype of the igr knockout strain of Mycobacterium tuberculosis; the loss of ChsE1-ChsE2 can be compensated for by ChsE4-ChsE5 during the chronic phase of infection. The X-ray crystallographic structure of ChsE4-ChsE5 was determined to a resolution of 2.0 Å and represents the first high-resolution structure of a heterotetrameric acyl-CoA dehydrogenase (ACAD). Unlike typical homotetrameric ACADs that bind four flavin adenine dinucleotide (FAD) cofactors, ChsE4-ChsE5 binds one FAD at each dimer interface, resulting in only two substrate-binding sites rather than the classical four active sites. A comparison of the ChsE4-ChsE5 substrate-binding site to those of known mammalian ACADs reveals an enlarged binding cavity that accommodates steroid substrates and highlights novel prospects for designing inhibitors against the committed β-oxidation step in the first

  9. [Depression, anxiety and suicide risk symptoms among medical residents over an academic year].

    PubMed

    Jiménez-López, José Luis; Arenas-Osuna, Jesús; Angeles-Garay, Ulises

    2015-01-01

    Introducción: uno de los orígenes de la insatisfacción de los médicos residentes está relacionado con el síndrome de burnout, el estrés y la depresión. El objetivo es describir la prevalencia y las características clínicas de los síntomas de depresión, ansiedad y riesgo de suicidio y su correlación con trastorno mental en residentes de medicina a lo largo de un año académico. Métodos: se incluyeron 108 residentes de segundo año que respondieron el inventario de depresión de Beck, el inventario de ansiedad rasgo-estado y la escala de riesgo suicida de Plutchik al inicio del ciclo académico, así como seis y doce meses después. Resultados: en la primera medición se reportó una prevalencia de 3.7 % para síntomas de depresión, 38 % para síntomas de ansiedad y 1.9 % para riesgo de suicidio; a los seis meses la prevalencia aumentó a 22.2 % para depresión, 56.5 % para ansiedad y 7.4 % para riesgo de suicidio. El análisis estadístico mostró diferencias significativas entre las tres mediciones (p < 0.001). La prevalencia de trastorno depresivo fue de 4.6 %. Casi todos los residentes que desarrollaron trastorno depresivo tenían antecedente personal de depresión. El ambiente académico y laboral tuvo poca asociación con los trastornos. Conclusiones: es recomendable la detección de residentes con vulnerabilidad a la depresión con el objeto de que reciban atención oportuna en caso de que desarrollen trastorno depresivo.

  10. A Global Scale Scenario for Prebiotic Chemistry: Silica-Based Self-Assembled Mineral Structures and Formamide.

    PubMed

    Saladino, Raffaele; Botta, Giorgia; Bizzarri, Bruno Mattia; Di Mauro, Ernesto; Garcia Ruiz, Juan Manuel

    2016-05-17

    The pathway from simple abiotically made organic compounds to the molecular bricks of life, as we know it, is unknown. The most efficient geological abiotic route to organic compounds results from the aqueous dissolution of olivine, a reaction known as serpentinization (Sleep, N.H., et al. (2004) Proc. Natl. Acad. Sci. USA 101, 12818-12822). In addition to molecular hydrogen and a reducing environment, serpentinization reactions lead to high-pH alkaline brines that can become easily enriched in silica. Under these chemical conditions, the formation of self-assembled nanocrystalline mineral composites, namely silica/carbonate biomorphs and metal silicate hydrate (MSH) tubular membranes (silica gardens), is unavoidable (Kellermeier, M., et al. In Methods in Enzymology, Research Methods in Biomineralization Science (De Yoreo, J., Ed.) Vol. 532, pp 225-256, Academic Press, Burlington, MA). The osmotically driven membranous structures have remarkable catalytic properties that could be operating in the reducing organic-rich chemical pot in which they form. Among one-carbon compounds, formamide (NH2CHO) has been shown to trigger the formation of complex prebiotic molecules under mineral-driven catalytic conditions (Saladino, R., et al. (2001) Biorganic & Medicinal Chemistry, 9, 1249-1253), proton irradiation (Saladino, R., et al. (2015) Proc. Natl. Acad. Sci. USA, 112, 2746-2755), and laser-induced dielectric breakdown (Ferus, M., et al. (2015) Proc Natl Acad Sci USA, 112, 657-662). Here, we show that MSH membranes are catalysts for the condensation of NH2CHO, yielding prebiotically relevant compounds, including carboxylic acids, amino acids, and nucleobases. Membranes formed by the reaction of alkaline (pH 12) sodium silicate solutions with MgSO4 and Fe2(SO4)3·9H2O show the highest efficiency, while reactions with CuCl2·2H2O, ZnCl2, FeCl2·4H2O, and MnCl2·4H2O showed lower reactivities. The collections of compounds forming inside and outside the tubular membrane are

  11. A Global Scale Scenario for Prebiotic Chemistry: Silica-Based Self-Assembled Mineral Structures and Formamide

    PubMed Central

    2016-01-01

    The pathway from simple abiotically made organic compounds to the molecular bricks of life, as we know it, is unknown. The most efficient geological abiotic route to organic compounds results from the aqueous dissolution of olivine, a reaction known as serpentinization (Sleep, N.H., et al. (2004) Proc. Natl. Acad. Sci. USA 101, 12818–12822). In addition to molecular hydrogen and a reducing environment, serpentinization reactions lead to high-pH alkaline brines that can become easily enriched in silica. Under these chemical conditions, the formation of self-assembled nanocrystalline mineral composites, namely silica/carbonate biomorphs and metal silicate hydrate (MSH) tubular membranes (silica gardens), is unavoidable (Kellermeier, M., et al. In Methods in Enzymology, Research Methods in Biomineralization Science (De Yoreo, J., Ed.) Vol. 532, pp 225–256, Academic Press, Burlington, MA). The osmotically driven membranous structures have remarkable catalytic properties that could be operating in the reducing organic-rich chemical pot in which they form. Among one-carbon compounds, formamide (NH2CHO) has been shown to trigger the formation of complex prebiotic molecules under mineral-driven catalytic conditions (Saladino, R., et al. (2001) Biorganic & Medicinal Chemistry, 9, 1249–1253), proton irradiation (Saladino, R., et al. (2015) Proc. Natl. Acad. Sci. USA, 112, 2746–2755), and laser-induced dielectric breakdown (Ferus, M., et al. (2015) Proc Natl Acad Sci USA, 112, 657–662). Here, we show that MSH membranes are catalysts for the condensation of NH2CHO, yielding prebiotically relevant compounds, including carboxylic acids, amino acids, and nucleobases. Membranes formed by the reaction of alkaline (pH 12) sodium silicate solutions with MgSO4 and Fe2(SO4)3·9H2O show the highest efficiency, while reactions with CuCl2·2H2O, ZnCl2, FeCl2·4H2O, and MnCl2·4H2O showed lower reactivities. The collections of compounds forming inside and outside the tubular

  12. A Global Scale Scenario for Prebiotic Chemistry: Silica-Based Self-Assembled Mineral Structures and Formamide.

    PubMed

    Saladino, Raffaele; Botta, Giorgia; Bizzarri, Bruno Mattia; Di Mauro, Ernesto; Garcia Ruiz, Juan Manuel

    2016-05-17

    The pathway from simple abiotically made organic compounds to the molecular bricks of life, as we know it, is unknown. The most efficient geological abiotic route to organic compounds results from the aqueous dissolution of olivine, a reaction known as serpentinization (Sleep, N.H., et al. (2004) Proc. Natl. Acad. Sci. USA 101, 12818-12822). In addition to molecular hydrogen and a reducing environment, serpentinization reactions lead to high-pH alkaline brines that can become easily enriched in silica. Under these chemical conditions, the formation of self-assembled nanocrystalline mineral composites, namely silica/carbonate biomorphs and metal silicate hydrate (MSH) tubular membranes (silica gardens), is unavoidable (Kellermeier, M., et al. In Methods in Enzymology, Research Methods in Biomineralization Science (De Yoreo, J., Ed.) Vol. 532, pp 225-256, Academic Press, Burlington, MA). The osmotically driven membranous structures have remarkable catalytic properties that could be operating in the reducing organic-rich chemical pot in which they form. Among one-carbon compounds, formamide (NH2CHO) has been shown to trigger the formation of complex prebiotic molecules under mineral-driven catalytic conditions (Saladino, R., et al. (2001) Biorganic & Medicinal Chemistry, 9, 1249-1253), proton irradiation (Saladino, R., et al. (2015) Proc. Natl. Acad. Sci. USA, 112, 2746-2755), and laser-induced dielectric breakdown (Ferus, M., et al. (2015) Proc Natl Acad Sci USA, 112, 657-662). Here, we show that MSH membranes are catalysts for the condensation of NH2CHO, yielding prebiotically relevant compounds, including carboxylic acids, amino acids, and nucleobases. Membranes formed by the reaction of alkaline (pH 12) sodium silicate solutions with MgSO4 and Fe2(SO4)3·9H2O show the highest efficiency, while reactions with CuCl2·2H2O, ZnCl2, FeCl2·4H2O, and MnCl2·4H2O showed lower reactivities. The collections of compounds forming inside and outside the tubular membrane are

  13. Hydrodynamic collective effects of active proteins in biological membranes.

    PubMed

    Koyano, Yuki; Kitahata, Hiroyuki; Mikhailov, Alexander S

    2016-08-01

    Lipid bilayers forming biological membranes are known to behave as viscous two-dimensional fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it was shown [A. S. Mikhailov and R. Kapral, Proc. Natl. Acad. Sci. USA 112, E3639 (2015)PNASA60027-842410.1073/pnas.1506825112] that such active proteins should induce nonthermal fluctuating lipid flows leading to diffusion enhancement and chemotaxislike drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them. PMID:27627343

  14. Calcium wave propagation by calcium-induced calcium release: an unusual excitable system.

    PubMed

    Sneyd, J; Girard, S; Clapham, D

    1993-03-01

    We discuss in detail the behaviour of a model, proposed by Goldbeter et al. (1990. Proc. natn. Acad. Sci. 87, 1461-1465), for intracellular calcium wave propagation by calcium-induced calcium release, focusing our attention on excitability and the propagation of waves in one spatial dimension. The model with no diffusion behaves like a generic excitable system, and threshold behaviour, excitability and oscillations can be understood within this general framework. However, when diffusion is included, the model no longer behaves like a generic excitable system; the fast and slow variables are not distinct and previous results on excitable systems do not necessarily apply. We consider a piecewise linear simplification of the model, and construct travelling pulse and periodic plane wave solutions to the simplified model. The analogous behaviour in the full model is studied numerically. Goldbeter's model for calcium-induced calcium release is an excitable system of a type not previously studied in detail.

  15. Momir H. Polenakovic - Founder of the Nephrology Associations in the Republic of Macedonia.

    PubMed

    Spasovski, Goce; Stojceva-Taneva, Olivera

    2015-01-01

    Acad. Momir Polenakovic has devoted his life and work in the diagnosis and treatment of kidney patients, as well as in research of kidney disease. The great experience he has acquired in the work with kidney patients, and after the visit to the most renowned nephrology centers in Europe and the world, he has transferred it to his colleagues through the work in the medical and nephrology associations. The work of the associations was in fact a successful education of young doctors and specialists. Among his most distinguished positions, we can mention: President of the Macedonian Medical Association, founder and President of the MSNDTAO, President of the Yugoslav Society of Nephrology, founder and President of BANTAO, as well as member of the Boards of ESAO and ERA-EDTA. He has received a lot of recognitions for his work achievements. PMID:27442373

  16. Challenges to reestablishment of free-ranging populations of black-footed ferrets

    USGS Publications Warehouse

    Biggins, D.E.; Godbey, J.L.

    2003-01-01

    The black-footed ferret (Mustela nigripes) of North America is critically endangered due in part to its extreme specialization on formerly stable and abundant prairie dogs (Cynomys). Its close relative, the Siberian polecat (M. eversmannii) seems to have been subjected to a varying environment that was not conducive to specialization. One source of environmental variation in Asian steppes was plague (caused by Yersina pestis), which was absent from North America. Introduction of plague to North America presents serious challenges to ferret recovery. Partial solutions to other biological and political problems have been found, resulting in improved production in captivity, increased survival post-release, and thriving populations in plague-free South Dakota. ?? 2003 Acade??mie des sciences. Published by E??ditions scientifiques et me??dicales Elsevier SAS. All rights reserved.

  17. Evolution of new functions de novo and from preexisting genes.

    PubMed

    Andersson, Dan I; Jerlström-Hultqvist, Jon; Näsvall, Joakim

    2015-06-01

    How the enormous structural and functional diversity of new genes and proteins was generated (estimated to be 10(10)-10(12) different proteins in all organisms on earth [Choi I-G, Kim S-H. 2006. Evolution of protein structural classes and protein sequence families. Proc Natl Acad Sci 103: 14056-14061] is a central biological question that has a long and rich history. Extensive work during the last 80 years have shown that new genes that play important roles in lineage-specific phenotypes and adaptation can originate through a multitude of different mechanisms, including duplication, lateral gene transfer, gene fusion/fission, and de novo origination. In this review, we focus on two main processes as generators of new functions: evolution of new genes by duplication and divergence of pre-existing genes and de novo gene origination in which a whole protein-coding gene evolves from a noncoding sequence. PMID:26032716

  18. How are static magnetic fields detected biologically?

    NASA Astrophysics Data System (ADS)

    Finegold, Leonard

    2009-03-01

    There is overwhelming evidence that life, from bacteria to birds to bats, detects magnetic fields, using the fields for orientation or navigation. Indeed there are recent reports (based on Google Earth imagery) that cattle and deer align themselves with the earth's magnetic field. [1]. The development of frog and insect eggs are changed by high magnetic fields, probably through known physical mechanisms. However, the mechanisms for eukaryotic navigation and alignment are not clear. Persuasive published models will be discussed. Evidence, that static magnetic fields might produce therapeutic effects, will be updated [2]. [4pt] [1] S. Begall, et al., Proc Natl Acad Sci USA, 105:13451 (2008). [0pt] [2] L. Finegold and B.L. Flamm, BMJ, 332:4 (2006).

  19. Competencias en ética biocéntrica

    PubMed Central

    Stepke, Fernando Lolas

    2013-01-01

    Resumen Este artículo explora el origen y la conceptualización de la bioética en tanto ética biocéntrica, definida por el pionero Fritz Jahr como un imperativo hipotético que llama a respetar la vida en todas sus formas. Tras describirla como proceso social, procedimiento técnico y producto académico, se enumeran y comentan algunas competencias que debieran presidir el empleo del discurso bioético en cualquier punto del complejo social “investigación médica”: miembros de comités de ética de investigación, investigadores, empresarios, administradores. Cada uno de estos grupos, en su “cultura epistémica” propia, define y explicita los principios básicos en tanto expresión de valores y leyes generales. PMID:23459767

  20. Demonstration of the amphiphilic character of hormone-sensitive lipase by temperature-induced phase separation in Triton X-114 and charge-shift electrophoresis.

    PubMed

    Holm, C; Fredrikson, G; Belfrage, P

    1986-11-25

    Temperature-induced phase separation in Triton X-114 (Bordier, C. (1981) J. Biol. Chem. 256, 1604-1607) and charge-shift electrophoresis (Helenius, A., and Simons, K. (1977) Proc. Natl. Acad. Sci. U. S. A. 74, 529-532) were used to examine the amphiphilic character of hormone-sensitive lipase, purified from rat adipose tissue. In contrast to ATP-citrate lyase, a reference hydrophilic protein, the lipase was shown to partition predominantly (approximately 80%) into the detergent-rich phase upon phase separation in Triton X-114. Furthermore, its electrophoretic mobility was markedly shifted anodally and cathodally upon charge-shift electrophoresis in the presence of sodium taurodeoxycholate and cetyltrimethylammonium bromide, respectively. The results demonstrate that hormone-sensitive lipase possesses detergent-binding hydrophobic domain(s) and exhibits the same amphiphilicity as typical intrinsic membrane proteins.

  1. [Competence in biocentric ethics.

    PubMed

    Stepke, Fernando Lolas

    2012-07-01

    ResumenEste artículo explora el origen y la conceptualización de la bioética en tanto ética biocéntrica, definida por el pionero Fritz Jahr como un imperativo hipotético que llama a respetar la vida en todas sus formas. Tras describirla como proceso social, procedimiento técnico y producto académico, se enumeran y comentan algunas competencias que debieran presidir el empleo del discurso bioético en cualquier punto del complejo social "investigación médica": miembros de comités de ética de investigación, investigadores, empresarios, administradores. Cada uno de estos grupos, en su "cultura epistémica" propia, define y explicita los principios básicos en tanto expresión de valores y leyes generales.

  2. Weighing the deep continental biosphere.

    PubMed

    McMahon, Sean; Parnell, John

    2014-01-01

    There is abundant evidence for widespread microbial activity in deep continental fractures and aquifers, with important implications for biogeochemical cycling on Earth and the habitability of other planetary bodies. Whitman et al. (P Natl Acad Sci USA, 95, 1998, 6578) estimated a continental subsurface biomass on the order of 10(16) -10(17) g C. We reassess this value in the light of more recent data including over 100 microbial population density measurements from groundwater around the world. Making conservative assumptions about cell carbon content and the ratio of attached and free-living microorganisms, we find that the evidence continues to support a deep continental biomass estimate of 10(16) -10(17) g C, or 2-19% of Earth's total biomass.

  3. Parole terms for a killer: directing caspase3/CAD induced DNA strand breaks to coordinate changes in gene expression.

    PubMed

    Larsen, Brian D; Megeney, Lynn A

    2010-08-01

    In a series of discoveries over the preceding decade, a number of laboratories have unequivocally established that apoptotic proteins and pathways are well conserved cell fate determinants, which act independent of a cell death response. Within this context, the role for apoptotic proteins in the induction of cell differentiation has been widely documented. Despite these discoveries, little information has been forthcoming regarding a conserved mechanism by which apoptotic proteins achieve this non-death outcome. In the following discussion, we will explore the premise that the penultimate step in apoptosis, genome wide DNA damage/strand breaks act as a conserved genomic reprogramming event necessary for cell differentiation (Larsen et al. Proc Natl Acad Sci USA 2010; 107:4230-5). Moreover, we hypothesis that directed DNA damage, as mediated by known apoptotic proteins, may participate in numerous forms of regulated gene expression.

  4. Antiviral activity of squalamine: Role of electrostatic membrane binding

    NASA Astrophysics Data System (ADS)

    Beckerman, Bernard; Qu, Wei; Mishra, Abhijit; Zasloff, Michael; Wong, Gerard; Luijten, Erik

    2012-02-01

    Recent workootnotetextM. Zasloff et al., Proc. Nat. Acad. Sci. (USA) 108, 15978 (2011). has demonstrated that squalamine, a molecule found in the liver of sharks, exhibits broad-spectrum antiviral properties. It has been proposed that this activity results from the charge-density matching of squalamine and phospholipid membranes, causing squalamine to bind to membranes and displace proteins such as Rac1 that are crucial for the viral replication cycle. Here we investigate this hypothesis by numerical simulation of a coarse-grained model for the competition between Rac1 and squalamine in binding affinity to a flat lipid bilayer. We perform free-energy calculations to test the ability of squalamine to condense stacked bilayer systems and thereby displace bulkier Rac1 molecules. We directly compare our findings to small-angle x-ray scattering results for the same setup.

  5. Lalande: his life (1732-1807) and works

    NASA Astrophysics Data System (ADS)

    Débarbat, Suzanne

    2005-05-01

    Lalande, born in Bourg-en-Bresse, made his first studies at the Jesuit College, later in Paris, attending Delisle's and Lemonnier's courses. He went to Berlin in 1751 for the determination of the lunar parallax, with Lacaille being in South Africa. Among the observatories in Paris, at the end of XVIIIth century, were the ones remaining to the Navy, the Royal Observatory, and the observatory named after the Military school. Being nominated as the head of this last observatory, Lalande asked his "nephew" to observe positions of stars, having in view a large catalogue. Together with other observers, he and hist wife obtained places for about 50,000 such objects, the so-called Lalande's Catalogue. Lalande is also famous for his writings, mostly his book whose title in French is "Astronomie" published in three editions. He was a member of the Académie des Sciences and of the Bureau des Longitudes.

  6. Simple molecular model for the binding of antibiotic molecules to bacterial ion channels

    NASA Astrophysics Data System (ADS)

    Mafé, Salvador; Ramírez, Patricio; Alcaraz, Antonio

    2003-10-01

    A molecular model aimed at explaining recent experimental data by Nestorovich et al. [Proc. Natl. Acad. Sci. USA 99, 9789 (2002)] on the interaction of ampicillin molecules with the constriction zone in a channel of the general bacterial porin, OmpF (outer membrane protein F), is presented. The model extends T. L. Hill's theory for intermolecular interactions in a pair of binding sites [J. Am. Chem. Soc. 78, 3330 (1956)] by incorporating two binding ions and two pairs of interacting sites. The results provide new physical insights on the role of the complementary pattern of the charge distributions in the ampicillin molecule and the narrowest part of the channel pore. Charge matching of interacting sites facilitates drug binding. The dependence of the number of ampicillin binding events per second with the solution pH and salt concentration is explained qualitatively using a reduced number of fundamental concepts.

  7. Formaldehyde photodissociation: Dependence on total angular momentum and rotational alignment of the CO product

    SciTech Connect

    Farnum, John D.; Zhang, Xiubin; Bowman, Joel M.

    2007-04-07

    Quasiclassical trajectory calculations are reported to investigate the effects of rotational excitation of formaldehyde on the branching ratios of the fragmentation products, H{sub 2}+CO and H+HCO. The results of tens of thousands of trajectories show that increased rotational excitation causes suppression of the radical channel and enhancement of the molecular channel. Decomposing the molecular channel into ''direct'' and ''roaming'' channels shows that increased rotation switches from suppressing to enhancing the roaming products across our chosen energy range. However, decomposition into these pathways is difficult because the difference between them does not appear to have a distinct boundary. A vector correlation investigation of the CO rotation shows different characteristics in the roaming versus direct channels and this difference is a potentially useful signature of the roaming mechanism, as first speculated by Kable and Houston in their experimental study of photodissociation of acetaldehyde [P. L. Houston and S. H. Kable, Proc. Nat. Acad. Sci. 103, 16079 (2006)].

  8. Exo-planet Direct Imaging with On-Axis and/or Segmented Apertures in Space: Adaptive Compensation of Aperture Discontinuities

    NASA Astrophysics Data System (ADS)

    Soummer, Remi

    Capitalizing on a recent breakthrough in wavefront control theory for obscured apertures made by our group, we propose to demonstrate a method to achieve high contrast exoplanet imaging with on-axis obscured apertures. Our new algorithm, which we named Adaptive Compensation of Aperture Discontinuities (ACAD), provides the ability to compensate for aperture discontinuities (segment gaps and/or secondary mirror supports) by controlling deformable mirrors in a nonlinear wavefront control regime not utilized before but conceptually similar to the beam reshaping used in PIAA coronagraphy. We propose here an in-air demonstration at 1E- 7 contrast, enabled by adding a second deformable mirror to our current test-bed. This expansion of the scope of our current efforts in exoplanet imaging technologies will enabling us to demonstrate an integrated solution for wavefront control and starlight suppression on complex aperture geometries. It is directly applicable at scales from moderate-cost exoplanet probe missions to the 2.4 m AFTA telescopes to future flagship UVOIR observatories with apertures potentially 16-20 m. Searching for nearby habitable worlds with direct imaging is one of the top scientific priorities established by the Astro2010 Decadal Survey. Achieving this ambitious goal will require 1e-10 contrast on a telescope large enough to provide angular resolution and sensitivity to planets around a significant sample of nearby stars. Such a mission must of course also be realized at an achievable cost. Lightweight segmented mirror technology allows larger diameter optics to fit in any given launch vehicle as compared to monolithic mirrors, and lowers total life-cycle costs from construction through integration & test, making it a compelling option for future large space telescopes. At smaller scales, on-axis designs with secondary obscurations and supports are less challenging to fabricate and thus more affordable than the off-axis unobscured primary mirror designs

  9. Fructan synthesis in transgenic tobacco and chicory plants expressing barley sucrose: fructan 6-fructosyltransferase.

    PubMed

    Sprenger, N; Schellenbaum, L; van Dun, K; Boller, T; Wiemken, A

    1997-01-01

    We have recently cloned a cDNA encoding sucrose:fructan 6-fructosyltransferase (6-SFT), a key enzyme of fructan synthesis forming the beta-2,6 linkages typical of the grass fructans, graminans and phleins [Sprenger et al. (1995) Proc. Natl. Acad. Sci. USA 92, 11652-11656]. Here we report functional expression of 6-SFT from barley in transgenic tobacco and chicory. Transformants of tobacco, a plant naturally unable to form fructans, synthesized the trisaccharide kestose and a series of unbranched fructans of the phlein type (beta-2,6 linkages). Transformants of chicory, a plant naturally producing only unbranched fructans of the inulin type (beta-2,1 linkages), synthesized in addition branched fructans of the graminan type, particularly the tetrasaccharide bifurcose which is also a main fructan in barley leaves.

  10. The Observation of Highly Ordered Domains in Membranes with Cholesterol

    SciTech Connect

    Armstrong, Clare L; Marquardt, Drew; Dies, Hannah; Kucerka, Norbert; Yamani, Zahra; Harroun, Thad; Katsaras, John; Shi, A-C; Rheinstadter, Maikel C

    2013-01-01

    Rafts, or functional domains, are transient nano- or mesoscopic structures in the exoplasmic leaflet of the plasma membrane, and are thought to be essential for many cellular processes. Using neutron diffraction and computer modelling, we present evidence for the existence of highly ordered lipid domains in the cholesterol-rich (32.5 mol%) liquid-ordered (lo) phase of dipalmitoylphosphatidylcholine membranes. The liquid ordered phase in one-component lipid membranes has previously been thought to be a homogeneous phase. The presence of highly ordered lipid domains embedded in a disordered lipid matrix implies non-uniform distribution of cholesterol between the two phases. The experimental results are in excellent agreement with recent computer simulations of DPPC/cholesterol complexes [Meinhardt, Vink and Schmid (2013). Proc Natl Acad Sci USA 110(12): 4476 4481], which reported the existence of nanometer size lo domains in a liquid disordered lipid environment.

  11. The kinetics of heterogeneous nucleation and growth: an approach based on a grain explicit model

    NASA Astrophysics Data System (ADS)

    Rouet-Leduc, B.; Maillet, J.-B.; Denoual, C.

    2014-04-01

    A model for phase transitions initiated on grain boundaries is proposed and tested against numerical simulations: this approach, based on a grain explicit model, allows us to consider the granular structure, resulting in accurate predictions for a wide span of nucleation processes. Comparisons are made with classical models of homogeneous (JMAK: Johnson and Mehl 1939 Trans. Am. Inst. Min. Eng. 135 416; Avrami 1939 J. Chem. Phys. 7 1103; Kolmogorov 1937 Bull. Acad. Sci. USSR, Mat. Ser. 1 335) as well as heterogeneous (Cahn 1996 Thermodynamics and Kinetics of Phase Transformations Im et al (Pittsburgh: Materials Research Society)) nucleation. A transition scale based on material properties is proposed, allowing us to discriminate between random and site-saturated regimes. Finally, we discuss the relationship between an Avrami-type exponent and the transition regime, establishing conditions for its extraction from experiments.

  12. Role of DNA gyrase in phiX replicative-form replication in vitro.

    PubMed Central

    Marians, K J; Ikeda, J E; Schlagman, S; Hurwitz, J

    1977-01-01

    Preparations containing DNA gyrase activity Gellert, M., Mizuchi, K., O'Dea, M.H. & Nash, H.A. (1976) Proc. Natl. Acad. Sci. USA 73, 3872-3876] have been extensively purified from Escherichia coli. Such fractions, in the presence of ATP and Mg2+, catalyze supertwisting of relaxed circular double-stranded DNA replicative forms of a number of DNAs that results in the formation of superhelical replicative forms. Relaxed phiX174 replicative form (phiX RFIV) is not attacked by the A protein endonuclease coded for by the phiX DNA genome. After exposure to preparations of DNA gyrase, the relaxed phiX174 replicative form is converted to phiX RFI which can then be attacked by the phiX gene A protein and participate in replication of duplex phiX DNA. PMID:266716

  13. Post-stishovite transition in AlOOH-incorporated SiO2

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Umemoto, K.; Wentzcovitch, R. M.; Hirose, K.

    2010-12-01

    In 2007, Lakshtanov et al. [Proc. Nat. Acad. Sci. 104, 13588 (2007)] demonstrated that the incorporation of AlOOH into SiO2 significantly reduces the transition pressure between stishovite and CaCl2-type phases. In the present paper, we investigate theoretically the effect of hydrogen (and aluminum) on this transition. First-principles calculations show that aluminum has no effect on the transition pressure. However, hydrogen bonds play a crucial role, suggesting that a cooperative redistribution of hydrogens aids the post-stishovite transition. Large-scale molecular dynamics simulations using model potentials confirm this effect and reveal the nature of the hydrogen motion. This effect produces a strong temperature dependence on the transition pressure and should make the latter sensitive to hydrogen content in the material. This work was supported by NSF under ATM-0428774 (VLab), EAR-0757903, and EAR-1019853. The computations were performed at the Minnesota Supercomputing Institute (MSI).

  14. Electron spin resonance dating of human teeth from Toca da Santa shelter of São Raimundo Nonato, Piauí, Brazil

    NASA Astrophysics Data System (ADS)

    Kinoshita, A.; Figueiredo, A. M. G.; Felice, G. D.; Lage, M. C. S. M.; Guidon, N.; Baffa, O.

    2008-02-01

    Results of the dating of fossil human teeth excavated from a shelter in the surroundings areas of the Serra da Capivara National Park, São Raimundo Nonato, Piauí, Brazil are presented. This shelter was partially excavated to search for more data that could improve the archaeological context of the Garrincho’s limestone hill sites, where the Toca do Gordo do Garrincho shelter provided two human teeth dated by conventional C-14 in (12,170 ± 40) yBP (years before present) and calibrated age (2 Sigma, 95% probability) 15,245 14,690 yBP (Beta 136204) [E. Peyre, C. Guérin, N. Guidon, I. Coppens, CR Acad. Sci. Paris, Sciences de la terre et des planètes/ Earth & Planetary Sciences 327 (1998) 335, [1

  15. Gaming and Religion: The Impact of Spirituality and Denomination.

    PubMed

    Braun, Birgit; Kornhuber, Johannes; Lenz, Bernd

    2016-08-01

    A previous investigation from Korea indicated that religion might modulate gaming behavior (Kim and Kim in J Korean Acad Nurs 40:378-388, 2010). Our present study aimed to investigate whether a belief in God, practicing religious behavior and religious denomination affected gaming behavior. Data were derived from a Western cohort of young men (Cohort Study on Substance Use Risk Factors, n = 5990). The results showed that a stronger belief in God was associated with lower gaming frequency and smaller game addiction scale scores. In addition, practicing religiosity was related to less frequent online and offline gaming. Finally, Christians gamed less frequently and had lower game addiction scale scores than subjects without religious denomination. In the future, these results could prove useful in developing preventive and therapeutic strategies for the Internet gaming disorder. PMID:26590569

  16. Physical constraints on charge transport through bacterial nanowires

    SciTech Connect

    Polizzi, Nicholas F.; Skourtis, Spiros S.; Beratan, David N.

    2012-01-01

    Extracellular appendages of the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 were recently shown to sustain currents of 10{sup 10} electrons per second over distances of 0.5 microns [El-Naggar et al., Proc. Natl. Acad. Sci. U. S. A., 2010, 107, 18127]. However, the identity of the charge localizing sites and their organization along the “nanowire” remain unknown. We use theory to predict redox cofactor separation distances that would permit charge flow at rates of 10{sup 10} electrons per second over 0.5 microns for voltage biases of ≤1V, using a steady-state analysis governed by a non-adiabatic electron transport mechanism. We find the observed currents necessitate a multi-step hopping transport mechanism, with charge localizing sites separated by less than 1 nm and reorganization energies that rival the lowest known in biology.

  17. Physical constraints on charge transport through bacterial nanowires

    SciTech Connect

    Polizzi, Nicholas F.; Skourtis, Spiros S.; Beratan, David N.

    2011-10-17

    Extracellular appendages of the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 were recently shown to sustain currents of 10¹⁰ electrons per second over distances of 0.5 microns [El-Naggar et al., Proc. Natl. Acad. Sci. U. S. A., 2010, 107, 18127]. However, the identity of the charge localizing sites and their organization along the “nanowire” remain unknown. We use theory to predict redox cofactor separation distances that would permit charge flow at rates of 10¹⁰ electrons per second over 0.5 microns for voltage biases of ≤1V, using a steady-state analysis governed by a non-adiabatic electron transport mechanism. We find the observed currents necessitate a multi-step hopping transport mechanism, with charge localizing sites separated by less than 1 nm and reorganization energies that rival the lowest known in biology.

  18. Magnetic circular dichroism study of the selenium-substituted form (Fe3Se4) of bovine heart aconitase.

    PubMed Central

    Breton, J L; Farrar, J A; Kennedy, M C; Beinert, H; Thomson, A J

    1995-01-01

    The selenium-substituted inactive form of mitochondrial aconitase contains one [3Fe-4Se]1+/0 cluster [Surerus, Kennedy, Beinert and Münck (1989) Proc. Natl. Acad. Sci. U.S.A. 87, 9846-9850]. This cluster was studied in both oxidized and reduced states by magnetic CD (MCD) and EPR spectroscopy. In the MCD spectra, intensity and transition wavelength shifts are observed when compared with the spectra of the native [3Fe-4S]1+/0 cluster. These changes are used to differentiate between the charge-transfer transitions originating from inorganic and cysteinyl sulphur. Using also the data from the EPR spectra, the spin ground state is assigned as S = 1/2 for the oxidized [3Fe-4Se]1+ cluster and S = 2 for the reduced [3Fe-4Se]0 cluster. PMID:7575454

  19. Relativistic electromagnetic mass models in spherically symmetric spacetime

    NASA Astrophysics Data System (ADS)

    Maurya, S. K.; Gupta, Y. K.; Ray, Saibal; Chatterjee, Vikram

    2016-10-01

    Under the static spherically symmetric Einstein-Maxwell spacetime of embedding class one we explore possibility of constructing electromagnetic mass model where mass and other physical parameters have purely electromagnetic origin (Lorentz in Proc. Acad. Sci. Amst. 6, 1904). This work is in continuation of our earlier investigation of Maurya et al. (Eur. Phys. J. C 75:389, 2015a) where we developed an algorithm and found out three new solutions of electromagnetic mass model. In the present work we consider different metric potentials ν and λ and have analyzed them in a systematic way. It is observed that some of the previous solutions related to electromagnetic mass model are nothing but special cases of the presently obtained generalized solution set. We further verify the solution set and especially show that these are extremely applicable in the case of compact stars.

  20. An Englishman abroad: Charles Blagden's visit to Paris in 1783.

    PubMed

    Fauque, Danielle M E

    2008-12-20

    Once the preliminaries of peace had been signed in January 1783, after the war of American independence, exchanges between British and French men of science resumed their normal course. On a visit to Paris in 1783, the francophile Charles Blagden (with the encouragement of Joseph Banks) made a number of contacts that fostered relations between the Royal Society and the Académie royale des sciences. In the course of this and several subsequent visits to France, Blagden became especially intimate with the chemist Claude-Louis Berthollet. His correspondence, now in the Royal Society, is a rich source for our understanding of some of the leading scientific debates of the day, in particular concerning the nature of water, which forms the main subject of this article.

  1. Hubble's diagram and cosmic expansion

    NASA Astrophysics Data System (ADS)

    Kirshner, Robert P.

    2004-01-01

    Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168-173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology.

  2. Hubble's diagram and cosmic expansion.

    PubMed

    Kirshner, Robert P

    2004-01-01

    Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168-173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology. PMID:14695886

  3. Earthquake triggering and large-scale geologic storage of carbon dioxide

    PubMed Central

    Zoback, Mark D.; Gorelick, Steven M.

    2012-01-01

    Despite its enormous cost, large-scale carbon capture and storage (CCS) is considered a viable strategy for significantly reducing CO2 emissions associated with coal-based electrical power generation and other industrial sources of CO2 [Intergovernmental Panel on Climate Change (2005) IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by Working Group III of the Intergovernmental Panel on Climate Change, eds Metz B, et al. (Cambridge Univ Press, Cambridge, UK); Szulczewski ML, et al. (2012) Proc Natl Acad Sci USA 109:5185–5189]. We argue here that there is a high probability that earthquakes will be triggered by injection of large volumes of CO2 into the brittle rocks commonly found in continental interiors. Because even small- to moderate-sized earthquakes threaten the seal integrity of CO2 repositories, in this context, large-scale CCS is a risky, and likely unsuccessful, strategy for significantly reducing greenhouse gas emissions. PMID:22711814

  4. The significance of Cern

    ScienceCinema

    None

    2016-07-12

    Le Prof. V.Weisskopf, DG du Cern de 1961 à 1965, est né à Vienne, a fait ses études à Göttingen et a une carrière académique particulièrement riche. Il a travaillé à Berlin, Copenhague et Berlin et est parti aux Etats Unis pour participer au projet Manhattan et était Prof. au MTT jusqu'à 1960. Revenu en Europe, il a été DG du Cern et lui a donné l'impulsion que l'on sait.

  5. INCLUSIÓN DE LA ÉTICA Y BIOÉTICA EN LA FORMACIÓN DE PRE Y POSGRADO DEL CIRUJANO-DENTISTA EN PERÚ

    PubMed Central

    Rupaya, Carmen Rosa García

    2009-01-01

    Se revisan aspectos de la inclusión de la ética y bioética en la formación de pre y posgrado del cirujano-dentista en Perú. Desde el punto de vista de la formación del docente, se analiza la presencia de normatividad ética en la investigación científica que genera la universidad, así como los conocimientos y actitudes vinculados con la ética y bioética en la formación del odontólogo. Se concluye que es un compromiso fomentar un cambio de paradigma, a través de un movimiento masivo que involucre los ámbitos familiar, profesional y académico, con el n de integrar la reflexión ética en nuestro diario proceder. PMID:19946384

  6. [Nuclear arms and medical responsibility].

    PubMed

    Firket, H

    1999-01-01

    The medical profession would be unable to cope with the millions of simultaneous casualities of a nuclear war. Such a war between developed countries becomes less likely, but new countries equip themselves, with nuclear weapons, using the violation of the Non-Proliferation Treaty by the great powers as an excuse. The danger of nuclear war is spreading with the consequences one can imagine. A world movement, including military experts, political, moral and scientific leaders and representative national medical groups, among them the World Medical Association, press governments to negotiate a comprehensive abolition treaty. The "Académie royale de Médecine de Belgique" joining moral prestige to an authoritative expertise, should take a stand on the problem. PMID:10687249

  7. Thermodynamics of information processing based on enzyme kinetics: An exactly solvable model of an information pump

    NASA Astrophysics Data System (ADS)

    Cao, Yuansheng; Gong, Zongping; Quan, H. T.

    2015-06-01

    Motivated by the recent proposed models of the information engine [Proc. Natl. Acad. Sci. USA 109, 11641 (2012), 10.1073/pnas.1204263109] and the information refrigerator [Phys. Rev. Lett. 111, 030602 (2013), 10.1103/PhysRevLett.111.030602], we propose a minimal model of the information pump and the information eraser based on enzyme kinetics. This device can either pump molecules against the chemical potential gradient by consuming the information to be encoded in the bit stream or (partially) erase the information initially encoded in the bit stream by consuming the Gibbs free energy. The dynamics of this model is solved exactly, and the "phase diagram" of the operation regimes is determined. The efficiency and the power of the information machine is analyzed. The validity of the second law of thermodynamics within our model is clarified. Our model offers a simple paradigm for the investigating of the thermodynamics of information processing involving the chemical potential in small systems.

  8. Involvement of thioredoxin on the scaffold activity of NifU in heterocyst cells of the diazotrophic cyanobacterium Anabaena sp. strain PCC 7120.

    PubMed

    Nomata, Jiro; Maeda, Maki; Isu, Atsuko; Inoue, Kazuhito; Hisabori, Toru

    2015-09-01

    The diazotrophic cyanobacterium Anabaena sp. strain PCC 7120 (A.7120) differentiates into specialized heterocyst cells that fix nitrogen under nitrogen starvation conditions. Although reducing equivalents are essential for nitrogen fixation, little is known about redox systems in heterocyst cells. In this study, we investigated thioredoxin (Trx) networks in Anabaena using TrxM, and identified 16 and 38 candidate target proteins in heterocysts and vegetative cells, respectively, by Trx affinity chromatography (Motohashi et al. (Comprehensive survey of proteins targeted by chloroplast thioredoxin. Proc Natl Acad Sci USA, 2001; 98: , 11224-11229)). Among these, the Fe-S cluster scaffold protein NifU that facilitates functional expression of nitrogenase in heterocysts was found to be a potential TrxM target. Subsequently, we observed that the scaffold activity of N-terminal catalytic domain of NifU is enhanced in the presence of Trx-system, suggesting that TrxM is involved in the Fe-S cluster biogenesis.

  9. Structure of mutagen nucleic acid complexes in solution. Proton chemical shifts in 9-aminoacridine complexes with dG-dC, dC-dG, and dA-dT-dG-dC-dA-dT.

    PubMed

    Reuben, J; Baker, B M; Kallenbach, N R

    1978-07-11

    The influence of self-complementary oligodeoxynucleotides on the chemical shifts of protons of the mutagenic acridine dye 9-aminoacridine has been measured. Upfield shifts indicative of intercalative binding are found in the cases of dG-dC, dC-dG, and dA-dT-dG-dC-dA-dT but not in dA-dT. Geometries for the complexes that are compatibile with the chemical-shift data and the X-ray structure of the complex between ri5C-rG and 9-aminoacridine determined by Sakore et al. [Sakore, T.D., Jain, S.C., Tsai, C., and Sobell, H.M. (1977), Proc. Natl. Acad. Sci. U.S.A. 74, 188--192] can be identified using recent theoretical estimates of shifts induced by nucleotide bases.

  10. Stochastic model for scale-free networks with cutoffs

    NASA Astrophysics Data System (ADS)

    Simas, Tiago; Rocha, Luis M.

    2008-12-01

    We propose and analyze a stochastic model which explains, analytically, the cutoff behavior of real scale-free networks previously modeled computationally by Amaral [Proc. Natl. Acad. Sci. U.S.A. 97, 11149 (2000)] and others. We present a mathematical model that can explain several existing computational scale-free network generation models. This yields a theoretical basis to understand cutoff behavior in complex networks, previously treated only with simulations using distinct models. Therefore, ours is an integrative approach that unifies the existing literature on cutoff behavior in scale-free networks. Furthermore, our mathematical model allows us to reach conclusions not hitherto possible with computational models: the ability to predict the equilibrium point of active vertices and to relate the growth of networks with the probability of aging. We also discuss how our model introduces a useful way to classify scale free behavior of complex networks.

  11. 5p deletions: Current knowledge and future directions.

    PubMed

    Nguyen, Joanne M; Qualmann, Krista J; Okashah, Rebecca; Reilly, AmySue; Alexeyev, Mikhail F; Campbell, Dennis J

    2015-09-01

    Disorders resulting from 5p deletions (5p-) were first recognized by Lejeune et al. in 1963 [Lejeune et al. (1963); C R Hebd Seances Acad Sci 257:3098-3102]. 5p- is caused by partial or total deletion of the short arm of chromosome 5. The most recognizable phenotype is characterized by a high-pitched cry, dysmorphic features, poor growth, and developmental delay. This report reviews 5p- disorders and their molecular basis. Hemizygosity for genes located within this region have been implicated in contributing to the phenotype. A review of the genes on 5p which may be dosage sensitive is summarized. Because of the growing knowledge of these specific genes, future directions to explore potential targeted therapies for individuals with 5p- are discussed. © 2015 Wiley Periodicals, Inc. PMID:26235846

  12. CONDENSED MATTER: STRUCTURE, MECHANICAL AND THERMAL PROPERTIES: A Method to Design Synthetic Cell-Cycle Networks

    NASA Astrophysics Data System (ADS)

    Miao, Ke-Ke

    2009-07-01

    The interactions among proteins, DNA and RNA in an organism form elaborate cell-cycle networks which govern cell growth and proliferation. Understanding the common structure of cell-cycle networks will be of great benefit to science research. Here, inspired by the importance of the cell-cycle regulatory network of yeast which has been studied intensively, we focus on small networks with 11 nodes, equivalent to that of the cell-cycle regulatory network used by Li et al. [Proc. Natl. Acad. Sci. USA 101(2004)4781] Using a Boolean model, we study the correlation between structure and function, and a possible common structure. It is found that cascade-like networks with a great number of interactions between nodes are stable. Based on these findings, we are able to construct synthetic networks that have the same functions as the cell-cycle regulatory network.

  13. RS cyclophilins: identification of an NK-TR1-related cyclophilin.

    PubMed

    Nestel, F P; Colwill, K; Harper, S; Pawson, T; Anderson, S K

    1996-11-21

    We report the isolation of a large cyclophilin protein containing RS (arginine-serine) repeats from a yeast two-hybrid screen using ClK (CDC28/cdc2-like kinase) as a probe. This Clk associating RS-cyclophilin (CARS-Cyp) possesses 39% homology to the NK-TR1 (natural killer tumor recognition protein-1) we have previously characterized (Anderson et al. (1993) Proc. Natl. Acad. Sci. USA 90 (1993) 542-546). CARS-Cyp is expressed in a variety of tissues and cell types, and codes for a protein with a predicted mass of 89 kDa containing a cyclophilin-related domain, two Nopp140 (nucleolar phosphoprotein of 140 kDa)-related domains, and a large RS domain. The RS-cyclophilins, a novel class of proteins, may play an important role in the regulation of pre-mRNA splicing.

  14. Nano-Optics for Chemical and Materials Characterization

    NASA Astrophysics Data System (ADS)

    Beversluis, Michael; Stranick, Stephan

    2007-03-01

    Light microscopy can provide non-destructive, real-time, three-dimensional imaging with chemically-specific contrast, but diffraction frequently limits the resolution to roughly 200 nm. Recently, structured illumination techniques have allowed fluorescence imaging to reach 50 nm resolution [1]. Since these fluorescence techniques were developed for use in microbiology, a key challenge is to take the resolution-enhancing features and apply them to contrast mechanisms like vibrational spectroscopy (e.g., Raman and CARS microscopy) that provide morphological and chemically specific imaging.. We are developing a new hybrid technique that combines the resolution enhancement of structured illumination microscopy with scanning techniques that can record hyperspectral images with 100 nm spatial resolution. We will show such superresolving images of semiconductor nanostructures and discuss the advantages and requirements for this technique. Referenence: 1. M. G. L. Gustafsson, P. Natl. Acad. Sci. USA 102, 13081-13086 (2005).

  15. Theoretical analysis of the coherence-brightened laser in air

    NASA Astrophysics Data System (ADS)

    Yuan, Luqi; Hokr, Brett H.; Traverso, Andrew J.; Voronine, Dmitri V.; Rostovtsev, Yuri; Sokolov, Alexei V.; Scully, Marlan O.

    2013-02-01

    We present a detailed theoretical study of a recent experiment [A. J. Traverso , Proc. Natl. Acad. Sci. USAPNASA60027-842410.1073/pnas.1211481109 109, 15185 (2012)] in which a laserlike source is created in air by pumping with a nanosecond pulse. The source generates radiation in the forward and backward directions. The temporal behavior of the emitted pulses is investigated for different pump shapes and durations. Our analysis indicates that the spiky emission is due to quantum coherence via cooperation between atoms of an ensemble, which leads to strong-oscillatory superfluorescence. We show that these cooperative nonadiabatic coherence effects cannot be described by rate equations and instead a full set of the Maxwell-Bloch equations must be used. We consider a range of parameters and study transitions between various regimes. Understanding these coherence-brightened processes in air should lead to improvements in environmental, atmospheric remote sensing and other applications.

  16. Hubble's diagram and cosmic expansion

    PubMed Central

    Kirshner, Robert P.

    2004-01-01

    Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168–173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology. PMID:14695886

  17. Finite Time Extinction for Stochastic Sign Fast Diffusion and Self-Organized Criticality

    NASA Astrophysics Data System (ADS)

    Gess, Benjamin

    2015-04-01

    We prove finite time extinction for stochastic sign fast diffusion equations driven by linear multiplicative space-time noise, corresponding to the Bak-Tang-Wiesenfeld model for self-organized criticality. This solves a problem posed and left open in several works: (Barbu, Methods Appl Sci 36:1726-1733, 2013; Röckner and Wang, J Lond Math Soc (2) 87:545-560, 2013; Barbu et al. J Math Anal Appl 389:147-164, 2012; Barbu and Röckner, Comm Math Phys 311:539-555, 2012; Barbu et al., Comm Math Phys 285:901-923, 2009, C R Math Acad Sci Paris 347(1-2):81-84, 2009). The highly singular-degenerate nature of the drift in interplay with the stochastic perturbation causes the need for new methods in the analysis of mass diffusion, and several new estimates and techniques are introduced.

  18. The Discovery of an 1862 Drawing of M 51, the Whirlpool Nebula

    NASA Astrophysics Data System (ADS)

    Holberg, Jay B.; Tobin, W.

    2006-12-01

    An early drawing of the spiral galaxy Messier 51 in Canes Venatici has recently come to light. The drawing was made on 25 April 1862 by Jean Chacornac (1823-1873), at the Paris Observatory, using Léon Foucault’s then newly completed 80-cm silvered-glass reflector. Chacornac’s observation of M 51 was among the first results from the new telescope announced to the Académie des Sciences by observatory director Urbain Verrier in 1862. Although the existence of the drawing was known from Le Verrier’s description, the original had never been located. The circumstances surrounding the origin and the discovery of this drawing will be discussed and a brief comparison will be made with other nineteenth century drawings and photographs of M 51.

  19. LA BIOÉTICA COMO QUEHACER FILOSÓFICO

    PubMed Central

    Ferrer, Jorge José

    2009-01-01

    El artículo examina el estatuto epistemológico de la bioética como disciplina académica. El autor sostiene que el estatuto epistemológico de un discurso lo determina la pregunta fundamental que se plantea y la respuesta que se busca, focos integradores del discurso. En el caso de la bioética, la pregunta fundamental es de índole moral. La bioética es pues una disciplina ética que tiene su hogar epistemológico en la filosofía. El autor también defiende el concepto de “éticas aplicadas”. Sugiere finalmente que el método de la bioética, sobre todo la que se hace desde nuestras latitudes, debería adoptar el círculo hermenéutico como metodología para su filosofar. PMID:20463860

  20. Taste bud leptin: sweet dampened at initiation site.

    PubMed

    Travers, Susan P; Frank, Marion E

    2015-05-01

    The intriguing observation that leptin decreases sweet-evoked peripheral gustatory responses has aroused much interest (Kawai K, Sugimoto K, Nakashima K, Miura H, Ninomiya Y. 2000. Leptin as a modulator of sweet taste sensitivities in mice. Proc Natl Acad Sci U S A. 97(20):11044-11049.) due to its implied importance in controlling appetite. The effects of this anorexic hormone, however, appear more conditional than originally believed. In this issue of Chemical Senses, a careful study by Glendinning and colleagues, find no effects of leptin on sweet-evoked chorda tympani responses, whereas an equally careful study by Meredith and colleagues, find decreased release of ATP and increased release of 5-HT from taste buds in response to sweet stimuli.

  1. Eight years of bioethics

    PubMed Central

    Moreno-Exebio, Luis

    2012-01-01

    Este trabajo presenta la experiencia que significó el paso por el Programa Internacional de Formación en Ética de la investigación biomédica y psicosocial del Centro Interdisciplinario de Estudios en Bioética de la Universidad de Chile (2003–2004) y algunas reflexiones respecto de la integración de lo aprendido en mi posterior labor en comités de ética y programas académicos de ética de investigación. Asimismo, en la elaboración de regulaciones que permitan una mejor evaluación ética y científica. PMID:23172984

  2. A theory for depletion-induced colloidal membranes

    NASA Astrophysics Data System (ADS)

    Kang, Louis; Lubensky, Tom C.

    2014-03-01

    Depletion-induced formation of colloidal membranes has been recently observed in suspensions of hard rods [E. Barry and Z. Dogic, Proc. Natl. Acad. Sci. U.S.A. 107, 10348 (2010); T. Gibaud et al., Nature 481, 348 (2012)]. These membranes exhibit a variety of rich behaviors that must ultimately be driven by entropy alone. We propose an entropic model that can capture certain features of these membranes, including their curved edge shape and the presence of twist even with achiral rods. We calculate phenomenological parameters, such as the Frank twist constant and the Helfrich bending modulus, from physical quantities. Finally, we describe novel behaviors predicted by our model. We acknowledge support by NSF grant DMR-1104707.

  3. « Les fleurs du MAL » une méthode d'ondelettes adaptive de lignes arbitraires I : problèmes de convection diffusion

    NASA Astrophysics Data System (ADS)

    Ren, Xiaoan; Xanthis, Leonidas S.

    2004-01-01

    Baudelaire's 'les fleurs du mal' refers to various new developments ('les fleurs') of the method ofarbitrarylines ( mal), since it was first published (in C. R. Acad. Sci. Paris, Sér. I, in 1991). Here we revisit the basic mal (semi-discretization) methodology for stationary convection-diffusion problems and develop an adaptive, wavelet-based solver that is capable of capturing the thin layers that arise in such problems. We show the efficacy and high accuracy of the wavelet-mal solver by applying it to a challenging 2D problem involving both boundary and interior layers. To cite this article: X. Ren, L.S. Xanthis, C. R. Mecanique 332 (2004).

  4. Fractional Hamiltonian monodromy from a Gauss-Manin monodromy

    NASA Astrophysics Data System (ADS)

    Sugny, D.; Mardešić, P.; Pelletier, M.; Jebrane, A.; Jauslin, H. R.

    2008-04-01

    Fractional Hamiltonian monodromy is a generalization of the notion of Hamiltonian monodromy, recently introduced by [Nekhoroshev, Sadovskií, and Zhilinskií, C. R. Acad. Sci. Paris, Ser. 1 335, 985 (2002); Nekhoroshev, Sadovskií, and Zhilinskií, Ann. Henri Poincare 7, 1099 (2006)] for energy-momentum maps whose image has a particular type of nonisolated singularities. In this paper, we analyze the notion of fractional Hamiltonian monodromy in terms of the Gauss-Manin monodromy of a Riemann surface constructed from the energy-momentum map and associated with a loop in complex space which bypasses the line of singularities. We also prove some propositions on fractional Hamiltonian monodromy for 1:-n and m :-n resonant systems.

  5. Penetration of Action Potentials During Collision in the Median and Lateral Giant Axons of Invertebrates

    NASA Astrophysics Data System (ADS)

    Gonzalez-Perez, Alfredo; Budvytyte, Rima; Mosgaard, Lars D.; Nissen, Søren; Heimburg, Thomas

    2014-07-01

    The collisions of two simultaneously generated impulses in the giant axons of both earthworms and lobsters propagating in orthodromic and antidromic direction are investigated. The experiments have been performed on the extracted ventral cords of Lumbricus terrestris and the abdominal ventral cord of a lobster, Homarus americanus, by using external stimulation and recording. The collision of two nerve impulses of orthodromic and antidromic propagation did not result in the annihilation of the two signals, contrary to the common notion that is based on the existence of a refractory period in the well-known Hodgkin-Huxley theory. However, the results are in agreement with the electromechanical soliton theory for nerve-pulse propagation, as suggested by Heimburg and Jackson [On Soliton Propagation in Biomembranes and Nerves, Proc. Natl. Acad. Sci. U.S.A. 102, 9790 (2005).].

  6. Calculation of the wetting parameter from a cluster model in the framework of nanothermodynamics.

    PubMed

    García-Morales, V; Cervera, J; Pellicer, J

    2003-06-01

    The critical wetting parameter omega(c) determines the strength of interfacial fluctuations in critical wetting transitions. In this Brief Report, we calculate omega(c) from considerations on critical liquid clusters inside a vapor phase. The starting point is a cluster model developed by Hill and Chamberlin in the framework of nanothermodynamics [Proc. Natl. Acad. Sci. USA 95, 12779 (1998)]. Our calculations yield results for omega(c) between 0.52 and 1.00, depending on the degrees of freedom considered. The findings are in agreement with previous experimental results and give an idea of the universal dynamical behavior of the clusters when approaching criticality. We suggest that this behavior is a combination of translation and vortex rotational motion (omega(c)=0.84). PMID:16241275

  7. Differential conductance and defect states in the heavy-fermion superconductor CeCoIn5

    DOE PAGES

    John S. Van Dyke; Davis, James C.; Morr, Dirk K.

    2016-01-22

    We demonstrate that the electronic band structure extracted from quasiparticle interference spectroscopy [Nat. Phys. 9, 468 (2013)] and the theoretically computed form of the superconducting gaps [Proc. Natl. Acad. Sci. USA 111, 11663 (2014)] can be used to understand the dI/dV line shape measured in the normal and superconducting state of CeCoIn5 [Nat. Phys. 9, 474 (2013)]. In particular, the dI/dV line shape, and the spatial structure of defect-induced impurity states, reflects the existence of multiple superconducting gaps of dx2–y2 symmetry. As a result, these results strongly support a recently proposed microscopic origin of the unconventional superconducting state.

  8. [Competence in biocentric ethics.

    PubMed

    Stepke, Fernando Lolas

    2012-07-01

    ResumenEste artículo explora el origen y la conceptualización de la bioética en tanto ética biocéntrica, definida por el pionero Fritz Jahr como un imperativo hipotético que llama a respetar la vida en todas sus formas. Tras describirla como proceso social, procedimiento técnico y producto académico, se enumeran y comentan algunas competencias que debieran presidir el empleo del discurso bioético en cualquier punto del complejo social "investigación médica": miembros de comités de ética de investigación, investigadores, empresarios, administradores. Cada uno de estos grupos, en su "cultura epistémica" propia, define y explicita los principios básicos en tanto expresión de valores y leyes generales. PMID:23459767

  9. A finite element model for ice ball evolution in a multi-probe cryosurgery.

    PubMed

    Liu, Zhihong; Muldrew, Ken; Wan, Richard; Rewcastle, John

    2003-06-01

    The ice formation in a water body is examined for the computation of temperature field, phase change and a moving ice-water interface whose location is not known á priori. This is classically referred to as the Stefan problem [Rubinstein, L.I. (1971) The Stefan Problem (American Mathematical Society, Providence, Rhode Island 02904]. Based on the Duvaut [Duvaut, G. (1973) "Résolution d'un probléme Stefan" C.R. Acad Sci. Paris 276, 1461-1463] transformation, the governing equations for heat conduction are formulated within a variational principle that is readily amenable to a standard finite element solution without remeshing. Numerical simulation results pertaining to the freezing of tumour tissue in a multi-cryoprobe cryosurgery are presented. These results lend both quantitative and graphical support to the current empirical standards of "effective therapy" in view of refining clinical applications.

  10. Calculation of the wetting parameter from a cluster model in the framework of nanothermodynamics.

    PubMed

    García-Morales, V; Cervera, J; Pellicer, J

    2003-06-01

    The critical wetting parameter omega(c) determines the strength of interfacial fluctuations in critical wetting transitions. In this Brief Report, we calculate omega(c) from considerations on critical liquid clusters inside a vapor phase. The starting point is a cluster model developed by Hill and Chamberlin in the framework of nanothermodynamics [Proc. Natl. Acad. Sci. USA 95, 12779 (1998)]. Our calculations yield results for omega(c) between 0.52 and 1.00, depending on the degrees of freedom considered. The findings are in agreement with previous experimental results and give an idea of the universal dynamical behavior of the clusters when approaching criticality. We suggest that this behavior is a combination of translation and vortex rotational motion (omega(c)=0.84).

  11. Hydrodynamic collective effects of active proteins in biological membranes

    NASA Astrophysics Data System (ADS)

    Koyano, Yuki; Kitahata, Hiroyuki; Mikhailov, Alexander S.

    2016-08-01

    Lipid bilayers forming biological membranes are known to behave as viscous two-dimensional fluids on submicrometer scales; usually they contain a large number of active protein inclusions. Recently, it was shown [A. S. Mikhailov and R. Kapral, Proc. Natl. Acad. Sci. USA 112, E3639 (2015), 10.1073/pnas.1506825112] that such active proteins should induce nonthermal fluctuating lipid flows leading to diffusion enhancement and chemotaxislike drift for passive inclusions in biomembranes. Here, a detailed analytical and numerical investigation of such effects is performed. The attention is focused on the situations when proteins are concentrated within lipid rafts. We demonstrate that passive particles tend to become attracted by active rafts and are accumulated inside them.

  12. Learning radio astronomy by doing radio astronomy

    NASA Astrophysics Data System (ADS)

    Vaquerizo Gallego, J. A.

    2011-11-01

    PARTNeR (Proyecto Académico con el Radio Telescopio de NASA en Robledo, Academic Project with the NASA Radio Telescope at Robledo) is an educational program that allows high school and undergraduate students to control a 34 meter radio telescope and conduct radio astronomical observations via the internet. High-school teachers who join the project take a course to learn about the science of radio astronomy and how to use the antenna as an educational resource. Also, teachers are provided with learning activities they can do with their students and focused on the classroom implementation of the project within an interdisciplinary framework. PARTNeR provides students with firsthand experience in radio astronomy science. Thus, remote radio astronomical observations allow students to learn with a first rate scientific equipment the basics of radio astronomy research, aiming to arouse scientific careers and positive attitudes toward science. In this contribution we show the current observational programs and some recent results.

  13. Large-scale Individual-based Models of Pandemic Influenza Mitigation Strategies

    NASA Astrophysics Data System (ADS)

    Kadau, Kai; Germann, Timothy; Longini, Ira; Macken, Catherine

    2007-03-01

    We have developed a large-scale stochastic simulation model to investigate the spread of a pandemic strain of influenza virus through the U.S. population of 281 million people, to assess the likely effectiveness of various potential intervention strategies including antiviral agents, vaccines, and modified social mobility (including school closure and travel restrictions) [1]. The heterogeneous population structure and mobility is based on available Census and Department of Transportation data where available. Our simulations demonstrate that, in a highly mobile population, restricting travel after an outbreak is detected is likely to delay slightly the time course of the outbreak without impacting the eventual number ill. For large basic reproductive numbers R0, we predict that multiple strategies in combination (involving both social and medical interventions) will be required to achieve a substantial reduction in illness rates. [1] T. C. Germann, K. Kadau, I. M. Longini, and C. A. Macken, Proc. Natl. Acad. Sci. (USA) 103, 5935-5940 (2006).

  14. Controlling viral capsid assembly with templating

    NASA Astrophysics Data System (ADS)

    Hagan, Michael F.

    2008-05-01

    We develop coarse-grained models that describe the dynamic encapsidation of functionalized nanoparticles by viral capsid proteins. We find that some forms of cooperative interactions between protein subunits and nanoparticles can dramatically enhance rates and robustness of assembly, as compared to the spontaneous assembly of subunits into empty capsids. For large core-subunit interactions, subunits adsorb onto core surfaces en masse in a disordered manner, and then undergo a cooperative rearrangement into an ordered capsid structure. These assembly pathways are unlike any identified for empty capsid formation. Our models can be directly applied to recent experiments in which viral capsid proteins assemble around functionalized inorganic nanoparticles [Sun , Proc. Natl. Acad. Sci. U.S.A. 104, 1354 (2007)]. In addition, we discuss broader implications for understanding the dynamic encapsidation of single-stranded genomic molecules during viral replication and for developing multicomponent nanostructured materials.

  15. An extension of the steepest descent method for Riemann-Hilbert problems: the small dispersion limit of the Korteweg-de Vries (KdV) equation.

    PubMed

    Deift, P; Venakides, S; Zhou, X

    1998-01-20

    This paper extends the steepest descent method for Riemann-Hilbert problems introduced by Deift and Zhou in a critical new way. We present, in particular, an algorithm, to obtain the support of the Riemann-Hilbert problem for leading asymptotics. Applying this extended method to small dispersion KdV (Korteweg-de Vries) equation, we (i) recover the variational formulation of P. D. Lax and C. D. Levermore [(1979) Proc. Natl. Acad. Sci. USA76, 3602-3606] for the weak limit of the solution, (ii) derive, without using an ansatz, the hyperelliptic asymptotic solution of S. Venakides that describes the oscillations; and (iii) are now able to compute the phase shifts, integrating the modulation equations exactly. The procedure of this paper is a version of fully nonlinear geometrical optics for integrable systems. With some additional analysis the theory can provide rigorous error estimates between the solution and its computed asymptotic expression. PMID:11038618

  16. Physical constraints on charge transport through bacterial nanowires

    PubMed Central

    Polizzi, Nicholas F.; Skourtis, Spiros S.

    2012-01-01

    Extracellular appendages of the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 were recently shown to sustain currents of 1010 electrons per second over distances of 0.5 microns [El-Naggar et al., Proc. Natl. Acad. Sci. U. S. A., 2010, 107, 18127]. However, the identity of the charge localizing sites and their organization along the “nanowire” remain unknown. We use theory to predict redox cofactor separation distances that would permit charge flow at rates of 1010 electrons per second over 0.5 microns for voltage biases of ≤1V, using a steady-state analysis governed by a non-adiabatic electron transport mechanism. We find the observed currents necessitate a multi-step hopping transport mechanism, with charge localizing sites separated by less than 1 nm and reorganization energies that rival the lowest known in biology. PMID:22470966

  17. Note: Recombination of H{sup +} and OH{sup -} ions along water wires

    SciTech Connect

    Lee, Song Hi; Rasaiah, Jayendran C.

    2013-07-21

    Transport and recombination of hydrogen and hydroxide ions along a hydrogen-bonded water wire are studied by molecular dynamics simulation using a dissociating model for water. The results are compared with a recent CP-MD study of neutralization in bulk water [A. Hassanali, M. K. Prakrash, H. Eshet, and M. Parrinello, Proc. Natl. Acad. Sci. U.S.A. 108, 20410 (2011)]. The translocation of H{sup +} and OH{sup -} along the wire is faster than in the bulk water, followed by compression of the water wire when two water molecules separate the transported ions. Neutralization occurs with the concerted transfer of three protons as in the bulk water, followed by energy dissipation along the water chain.

  18. Shock waves in virus fitness evolution

    NASA Astrophysics Data System (ADS)

    Carvalhaes, Fernando Goldenstein; Goldman, Carla

    2007-06-01

    We consider a nonlinear partial differential equation of conservation type to describe the dynamics of transmission with sampling of viral populations observed in aliquots of fixed particle number taken from an evolving clone at periodic intervals of time [I.S. Novella, E.A. Duarte, S.F. Elena, A. Moya, E. Domingo, Exponential increases of RNA virus fitness during large population transmissions, Proc. Natl. Acad. Sci. USA 92 (1995) 5841-5844]. The fast processes of mutation and natural selection that occur within each transmission are incorporated into the conservation equation as parameters. With this, the changes in time behavior of fitness function noticed in experimental data are related to a crossover exhibited by the solutions to this equation in the transient regime for pulse-like initial conditions. As a consequence, the average replication rate of the population is predicted to reach a plateau as a power t.

  19. [Introduction to the commemorative session of the centennial of the death of Louis Pasteur].

    PubMed

    Le Minor, L

    1995-05-01

    When elected a member of Académie de médecine in 1873, Pasteur was well known for his achievements in chemistry, fermentation and silk worm diseases. He denied spontaneity of diseases, their cause are living germs. Passionate disputations took place in Academy on subjects of septicaemia, childbirth fever, or fowl cholera. In 1881, his success was obtained by vaccination of sheep against epidemic anthrax: his method of virus action softening was available for many human infections diseases, in spite of many disputations. The same method applied to rabies gave him universal glory. When he died in 1895, his views on infections diseases were accepted by Academie de medecine and all over the world.

  20. Plant biotechnology for food security and bioeconomy.

    PubMed

    Clarke, Jihong Liu; Zhang, Peng

    2013-09-01

    This year is a special year for plant biotechnology. It was 30 years ago, on January 18 1983, one of the most important dates in the history of plant biotechnology, that three independent groups described Agrobacterium tumefaciens-mediated genetic transformation at the Miami Winter Symposium, leading to the production of normal, fertile transgenic plants (Bevan et al. in Nature 304:184-187, 1983; Fraley et al. in Proc Natl Acad Sci USA 80:4803-4807, 1983; Herrera-Estrella et al. in EMBO J 2:987-995, 1983; Vasil in Plant Cell Rep 27:1432-1440, 2008). Since then, plant biotechnology has rapidly advanced into a useful and valuable tool and has made a significant impact on crop production, development of a biotech industry and the bio-based economy worldwide.

  1. Functional methods and effective potentials for non-linear composites

    NASA Astrophysics Data System (ADS)

    Pellegrini, Yves-Patrick; Barthélémy, Marc; Perrin, Gilles

    2000-03-01

    A formulation of variational principles in terms of functional integrals is proposed for any type of local plastic potentials. The minimization problem is reduced to the computation of a path integral. This integral can be used as a starting point for different approximations. As a first application, it is shown how to compute to second order the weak-disorder perturbative expansion of the effective potentials in random composite. The three-dimensional results of Suquet and Ponte-Castañeda (Suquet, P., Ponte-Castañeda, P., 1993. Small-contrast perturbation expansions for the effective properties of nonlinear composites. C. R. Acad. Sci. (Paris) Ser. II 317, 1515-1522) for the plastic dissipation potential with uniform applied tractions are retrieved and extended to any space dimension, taking correlations into account. In addition, the viscoplastic potential is also computed for uniform strain rates.

  2. A Science Superior to Music: Joseph Sauveur and the Estrangement between Music and Acoustics

    NASA Astrophysics Data System (ADS)

    Fix, Adam

    2015-09-01

    The scientific revolution saw a shift from the natural philosophy of music to the science of acoustics. Joseph Sauveur (1653-1716), an early pioneer in acoustics, determined that science as understood in the eighteenth century could not address the fundamental problems of music, particularly the problem of consonance. Building on Descartes, Mersenne, and Huygens especially, Sauveur drew a sharp divide between sound and music, recognizing the former as a physical phenomenon obeying mechanical and mathematical principles and the latter as an inescapably subjective and unquantifiable perception. While acoustics grew prominent in the Académie des sciences, music largely fell out of the scientific discourse, becoming primarily practiced art rather than natural philosophy. This study illuminates what was considered proper science at the dawn of the Enlightenment and why one particular branch of natural philosophy—music—did not make the cut.

  3. Configurations of an Articulated Arm and Singularities of Special Multi-Flags

    NASA Astrophysics Data System (ADS)

    Pelletier, Fernand; Slayman, Mayada

    2014-06-01

    P. Mormul has classified the singularities of special multi-flags in terms of "EKR class" encoded by sequences j_1,dots, j_k of integers (see [Singularity Theory Seminar, Warsaw University of Technology, Vol. 8, 2003, 87-100] and [Banach Center Publ., Vol. 65, Polish Acad. Sci., Warsaw, 2004, 157-178]). However, A.L. Castro and R. Montgomery have proposed in I>Israel J. Math. 192 (2012), 381-427] a codification of singularities of multi-flags by RC and RVT codes. The main results of this paper describe a decomposition of each ''EKR'' set of depth 1 in terms of RVT codes as well as characterize such a set in terms of configurations of an articulated arm. Indeed, an analogue description for some ''EKR'' sets of depth 2 is provided. All these results give rise to a complete characterization of all ''EKR'' sets for 1≤ k≤ 4.

  4. Three-qubit thermal entanglement via entanglement swapping on two-qubit Heisenberg XY chains

    SciTech Connect

    Kao, Zi Chong; Ng, Jezreel; Yeo, Ye

    2005-12-15

    In this paper, we consider the generation of a three-qubit Greenberger-Horne-Zeilinger-like thermal state by applying the entanglement swapping scheme of Zukowski et al. [Ann. N. Y. Acad. Sci. 755, 91 (1995)] to three pairs of two-qubit Heisenberg XY chains. The quality of the resulting three-qubit entanglement is studied by analyzing the teleportation fidelity, when it is used as a resource in the teleportation protocol of Karlsson et al. [Phys. Rev. A 58, 4394 (1998)]. We show that even though thermal noise in the original two-qubit states is amplified by the entanglement swapping process, we are still able to achieve nonclassical fidelities for the anisotropic Heisenberg XY chains at finitely higher and higher temperatures by adjusting the strengths of an external magnetic field. This has a positive implication on the solid-state realization of a quantum computer.

  5. Einstein-Weyl spaces and third-order differential equations

    NASA Astrophysics Data System (ADS)

    Tod, K. P.

    2000-08-01

    The three-dimensional null-surface formalism of Tanimoto [M. Tanimoto, "On the null surface formalism," Report No. gr-qc/9703003 (1997)] and Forni et al. [Forni et al., "Null surfaces formation in 3D," J. Math Phys. (submitted)] are extended to describe Einstein-Weyl spaces, following Cartan [E. Cartan, "Les espaces généralisées et l'integration de certaines classes d'equations différentielles," C. R. Acad. Sci. 206, 1425-1429 (1938); "La geometria de las ecuaciones diferenciales de tercer order," Rev. Mat. Hispano-Am. 4, 1-31 (1941)]. In the resulting formalism, Einstein-Weyl spaces are obtained from a particular class of third-order differential equations. Some examples of the construction which include some new Einstein-Weyl spaces are given.

  6. Spectral tripartitioning of networks

    NASA Astrophysics Data System (ADS)

    Richardson, Thomas; Mucha, Peter J.; Porter, Mason A.

    2009-09-01

    We formulate a spectral graph-partitioning algorithm that uses the two leading eigenvectors of the matrix corresponding to a selected quality function to split a network into three communities in a single step. In so doing, we extend the recursive bipartitioning methods developed by Newman [M. E. J. Newman, Proc. Natl. Acad. Sci. U.S.A. 103, 8577 (2006); Phys. Rev. E 74, 036104 (2006)] to allow one to consider the best available two-way and three-way divisions at each recursive step. We illustrate the method using simple “bucket brigade” examples and then apply the algorithm to examine the community structures of the coauthorship graph of network scientists and of U. S. Congressional networks inferred from roll call voting similarities.

  7. Information filtering via biased heat conduction.

    PubMed

    Liu, Jian-Guo; Zhou, Tao; Guo, Qiang

    2011-09-01

    The process of heat conduction has recently found application in personalized recommendation [Zhou et al., Proc. Natl. Acad. Sci. USA 107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction, which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix, and Delicious datasets could be improved by 43.5%, 55.4% and 19.2%, respectively, compared with the standard heat conduction algorithm and also the diversity is increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.

  8. Information filtering via biased heat conduction

    NASA Astrophysics Data System (ADS)

    Liu, Jian-Guo; Zhou, Tao; Guo, Qiang

    2011-09-01

    The process of heat conduction has recently found application in personalized recommendation [Zhou , Proc. Natl. Acad. Sci. USA PNASA60027-842410.1073/pnas.1000488107107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction, which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix, and Delicious datasets could be improved by 43.5%, 55.4% and 19.2%, respectively, compared with the standard heat conduction algorithm and also the diversity is increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.

  9. An item-oriented recommendation algorithm on cold-start problem

    NASA Astrophysics Data System (ADS)

    Qiu, Tian; Chen, Guang; Zhang, Zi-Ke; Zhou, Tao

    2011-09-01

    Based on a hybrid algorithm incorporating the heat conduction and probability spreading processes (Proc. Natl. Acad. Sci. U.S.A., 107 (2010) 4511), in this letter, we propose an improved method by introducing an item-oriented function, focusing on solving the dilemma of the recommendation accuracy between the cold and popular items. Differently from previous works, the present algorithm does not require any additional information (e.g., tags). Further experimental results obtained in three real datasets, RYM, Netflix and MovieLens, show that, compared with the original hybrid method, the proposed algorithm significantly enhances the recommendation accuracy of the cold items, while it keeps the recommendation accuracy of the overall and the popular items. This work might shed some light on both understanding and designing effective methods for long-tailed online applications of recommender systems.

  10. Induction of entropic segregation: the first step is the hardest.

    PubMed

    Minina, Elena; Arnold, Axel

    2014-08-21

    In confinement, overlapping polymers experience entropic segregating forces that tend to demix them. This plays a role during cell replication, where it facilitates the segregation of daughter chromosomes. It has been argued that these forces are strong enough to explain chromosome segregation in elongated bacteria such as E. coli without the need for additional active mechanisms [S. Jun and B. Mulder, Proc. Natl. Acad. Sci. U. S. A., 2006, 103, 12388]. However, entropic segregation can only set in after the initial symmetry has been broken. We demonstrate that the timescale for this induction phase is exponentially growing in the chain length, while the actual segregation time scales only quadratically in the chain length. Thus the induction quickly becomes the dominating, slow process, and makes entropic segregation much less efficient than previously thought. The slow induction might also explain the long delay in chromosome segregation observed in experiments on E. coli. PMID:24974935

  11. Response of Biomolecules to Ultrafast Laser Pulses

    NASA Astrophysics Data System (ADS)

    Allen, Roland; Dou, Yusheug; Dumitrica, Traian; Xie, John R. H.

    2005-03-01

    Using two complementary techniques -- semiclassical electron-radiation-ion dynamics (SERID) and time- dependent density functional theory (TDDFT) -- we are studying the response of various biologically relevant molecules to femtosecond-scale laser pulses. Our simulations provide microscopic information on mechanisms for photoisomerization [1] and other molecular transformations [2] and on spectroscopic identification of pathogens with schemes like FAST CARS [3]. The coupled dynamics of electrons and nuclei is determined by solving the time-dependent Schrödinger equation and using Ehrenfest's theorem, with a 30 attosecond time step. Results will be shown for molecules including stilbene, benzene, and dipicloninc acid. [1] Y. Dou and R. E. Allen, Chemical Physics Letters 378, 323 (2003).2] B. Torralva and R. E. Allen, Journal of Modern Optics 49, 593 - 625 (2002).3] M. O. Scully et al., Proc. Nat. Acad. Sci. 99, 10994 (2002).

  12. PARTNeR: A Tool for Outreach and Teaching Astronomy

    NASA Astrophysics Data System (ADS)

    Gallego, Juan Ángel Vaquerizo; Fuertes, Carmen Blasco

    PARTNeR is an acronym for Proyecto Académico con el Radio Telescopio de NASA en Robledo (Academic Project with the NASA Radio Telescope at Robledo). It is intended for general Astronomy outreach and, in particular, radioastronomy, throughout Spanish educational centres. To satisfy this target, a new educational material has been developed in 2007 to help not only teachers but also students. This material supports cross curricular programs and provides with the possibility of including Astronomy in related subjects like Physics, Chemistry, Technology, Mathematics or even English language. In this paper, the material that has been developed will be shown in detail and how it can be adapted to the disciplines from 4th year ESO (Enseñanza Secundaria Obligatoria-Compulsory Secondary Education) to High School. The pedagogic results obtained for the first year it has been implemented with students in classrooms will also be presented.

  13. Isolation and characterization of phosphorylated oligosaccharides from alpha-N-acetylglucosaminidase that are recognized by cell-surface receptors.

    PubMed

    von Figura, K; Klein, U

    1979-03-01

    Adsorptive endocytosis of lysosomal enzymes by fibroblasts and hepatocytes involves binding to cell surface receptors that recognize on lysosomal enzymes a phosphorylated carbohydrate, most likely a mannose 6-phosphate residue [Kaplan et al. (1977) Proc. Natl Acad. Sci. U.S.A. 74, 2026-2030; Ullrich et al. (1978) Hoppe-Seyler's Z. Physiol. Chem. 359, 1591-1598]. Loss of alpha-N-acetylglucosaminidase endocytosis after treatment with endoglucosaminidase H indicated that the recognition site of alpha-N-acetylglucosaminidase is located on N-glycosidically linked oligosaccharides of the high mannose type. Acidic oligosaccharides with an average molecular weight of 2200 were liberated from alpha-N-acetylglucosaminidase by endoglucosaminidase H. These oligosaccharides were susceptible to degradation by alkaline phosphatase, alpha-mannosidase and beta-N-acetylglucosaminidase. At the non-reducing terminal these oligosaccharides bear phosphorylated mannose and/or N-acetylglucosamine residues. PMID:428391

  14. Symmetry and Size of Membrane Protein Polyhedral Nanoparticles

    NASA Astrophysics Data System (ADS)

    Li, Di; Kahraman, Osman; Haselwandter, Christoph A.

    2016-09-01

    In recent experiments [T. Basta et al., Proc. Natl. Acad. Sci. U.S.A. 111, 670 (2014)] lipids and membrane proteins were observed to self-assemble into membrane protein polyhedral nanoparticles (MPPNs) with a well-defined polyhedral protein arrangement and characteristic size. We develop a model of MPPN self-assembly in which the preferred symmetry and size of MPPNs emerge from the interplay of protein-induced lipid bilayer deformations, topological defects in protein packing, and thermal effects. With all model parameters determined directly from experiments, our model correctly predicts the observed symmetry and size of MPPNs. Our model suggests how key lipid and protein properties can be modified to produce a range of MPPN symmetries and sizes in experiments.

  15. Spreading of block copolymer films and domain alignment at moving terrace steps

    NASA Astrophysics Data System (ADS)

    Belyi, Vladimir A.; Witten, Thomas A.

    2004-03-01

    We investigate spreading of phase separated copolymer films, where domain walls and thickness steps influence polymer flow. We show that at early stages of spreading its rate is determined by slow activated flow at terrace steps (i.e., thickness steps). At late stages of spreading, on the other hand, the rate is determined by the flow along terraces, with diffusionlike time dependence t-1/2. This dependence is similar to de Gennes and Cazabat's prediction for generic layered liquids [P. G. de Gennes and A. M. Cazabat, C.R. Acad. Sci. Paris II 310, 1601 (1990)], as opposed to the classical Tanner's law of drop spreading. We also argue that chain hopping at the spreading terrace steps should lead to the formation of aligned, defect-free domain patterns on the growing terraces.

  16. 5p Deletions: Current Knowledge and Future Directions

    PubMed Central

    Nguyen, Joanne M.; Qualmann, Krista J.; Okashah, Rebecca; Reilly, Amysue; Alexeyev, Mikhail F.; Campbell, Dennis J.

    2016-01-01

    Disorders resulting from 5p deletions (5p–) were first recognized by Lejeune et al. in 1963 [Lejeune et al. (1963); C R Hebd Seances Acad Sci 257:3098-3102]. 5p– is caused by partial or total deletion of the short arm of chromosome 5. The most recognizable phenotype is characterized by a high-pitched cry, dysmorphic features, poor growth, and developmental delay. This report reviews 5p– disorders and their molecular basis. Hemizygosity for genes located within this region have been implicated in contributing to the phenotype. A review of the genes on 5p which may be dosage sensitive is summarized. Because of the growing knowledge of these specific genes, future directions to explore potential targeted therapies for individuals with 5p– are discussed. PMID:26235846

  17. EDITORIAL Proceedings of the XIV International Conference on Small-Angle Scattering, SAS-2009

    NASA Astrophysics Data System (ADS)

    Ungar, Goran; Heenan, Richard

    2010-10-01

    There are 52 papers in these Proceedings. The papers are divided into 10 thematic sections and a section for invited papers and reviews. The sections and the respective section editors are given below. Section Editor(s) Invited Papers and Reviews Peter Griffiths, Wim Bras, Rudolf Winter Beamlines and Instrumentation Elliot Gilbert, Wim Bras, Nigel Rhodes Theory, Data processing and Modelling Jan Skov Pedersen, Carlo Knupp Biological Systems and Membranes Richard Heenan, Cameron Neylon Ceramics, Glasses and Porous Materials Rudolf Winter Colloids and Solutions Peter Griffiths Hierarchical Structures and Fibres Steve Eichhorn, Karen Edler Metallic and Magnetic Systems Armin Hoell Polymers Patrick Fairclough Time resolved Diffraction, Kinetic and Dynamical Studies João Cabral, Christoph Rau We are grateful to all section editors and the many anonymous referees for their invaluable effort which made the publication of the Proceedings possible. The refereeing process was strict and thorough, some papers were rejected and most were improved. The resulting compendium gives a good overview of recent developments in small-angle X-ray and neutron scattering theory, application, methods of analysis and instrumentation. Thus it should be a useful source of reference for a number of years to come. The papers are a good reflection of the material presented at the meeting. Because of the general high quality of the articles, it was difficult to decide which to highlight and be fair to all contributors. The following in particular have caught the attention of the editors. Highlighted papers A statistical survey of publications reporting the application of SAXS and SANS by Aldo Craievich (paper 012003) is recommended reading for anyone needing convincing about the vibrancy of this scientific field and the ever expanding use of these techniques. Two aspects of coherent X-ray scattering, made available by the advent of the 3rd generation synchrotron sources, are discussed in the

  18. Biomineral formation as a biosignature for microbial activities Precambrian cherts

    NASA Astrophysics Data System (ADS)

    Rincón Tomás, Blanca; Mühlen, Dominik; Hoppert, Michael; Reitner, Joachim

    2015-04-01

    In recent anoxic sediments manganese(II)carbonate minerals (e.g., rhodochrosite, kutnohorite) derive mainly from the reduction of manganese(IV) compounds by microbial anaerobic respiration. Small particles of rhodochrosite in stromatolite-like features in the Dresser chert Fm (Pilbara supergroup, W-Australia), associated with small flakes of kerogen, account for biogenic formation of the mineral in this early Archaean setting. Contrastingly, the formation of huge manganese-rich (carbonate) deposits requires effective manganese redox cycling, also conducted by various microbial processes, mainly requiring conditions of the early and late Proterozoic (Kirschvink et al., 2000; Nealson and Saffrani 1994). However, putative anaerobic pathways like microbial nitrate-dependent manganese oxidation (Hulth et al., 1999), anoxygenic photosynthesis (Johnson et al., 2013) and oxidation in UV light may facilitate manganese cycling even in a reducing atmosphere. Thus manganese redox cycling might have been possible even before the onset of oxygenic photosynthesis. Hence, there are several ways how manganese carbonates could have been formed biogenically and deposited in Precambrian sediments. Thus, the minerals may be suitable biosignatures for microbial redox processes in many respects. The hyperthermophilic archaeon Pyrobaculum islandicum produces rhodochrosite during growth on hydrogen and organic compounds and may be a putative model organism for the reduction of Mn(IV). References Hulth S, Aller RC, Gilbert F. (1999) Geochim Cosmochim Acta, 63, 49-66. Johnson JE, Webb SM, Thomas K, Ono S, Kirschvink JL, Fischer WW. (2013) Proc Natl Acad Sci USA, 110, 11238-11243. Kirschvink JL, Gaidos EJ, Bertani LE, Beukes NJ, Gutzmer J, Maepa LN, Steinberger LE. (2000) Proc Natl Acad Sci USA, 97, 1400-1405. Nealson KH, Saffarini D. (1994). Annu Rev Microbiol, 48, 311-343.

  19. Skin Cancer in the Crosshairs: Highlights from the Biennial Scientific Retreat of International Transplant Skin Cancer Collaborative and Skin Care in Organ Transplant Recipients Europe.

    PubMed

    Sinnya, Sudipta; Zwald, Fiona O; Colegio, Oscar R

    2015-08-01

    The International Transplant Skin Cancer Collaborative (ITSCC) is an organization comprising of physicians; transplant surgeons and basic science research scientists dedicated in providing optimal care and ongoing research advancements in solid organ transplant recipients to improve patient outcome and quality of life. As medical advances occur, it is anticipated that the sheer number of solid organ transplantations occurring worldwide will continue to increase. The long-term medication associated immunosuppression improves graft survival, but as a consequence, these individuals become increasingly susceptible to various cutaneous malignancies, lymphoproliferative disorders and infections. Squamous cell carcinoma is the most frequently encountered skin cancer and increases 65- to 250-fold [Jensen et al., Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens. J Am Acad Dermatol. 1999;40:177-186; Lindelöf et al., Incidence of skin cancer in 5356 patients following organ transplantation. Br J Dermatol. 2000; 143:513-519]. However, the rates of basal cell carcinoma, Merkel cell carcinoma and melanoma also increase in organ transplant recipients leading to significant morbidity as well as mortality [Berg and Otley. Skin cancer in organ transplant recipients: epidemiology, pathogenesis, and management. J Am Acad Dermatol. 2002; 47:1-20]. In October 2014, the International Transplant Skin Cancer Collaborative and its equivalent European counterpart, Skin Care in Organ Transplant Recipients Europe held its 10th biennial meeting in Essex, MA to discuss the clinical conundrums and the evolving research pertinent to the field. This meeting report provides a synthesis of all the clinical and research data presented at the 4-day meeting. PMID:27500228

  20. STRAIGHT-A STUDENTS DISLIKE PHYSICAL EDUCATION IN ADOLESCENCE: MYTH OR TRUTH? THE AVENA, AFINOS AND UP&DOWN STUDIES.

    PubMed

    Cañadas, Laura; Esteban-Cornejo, Irene; Ortega, Francisco B; Gomez-Martinez, Sonia; Casajús, José Antonio; Cabero, María Jesús; Calle, Maria E; Marcos, Ascensión; Veiga, Oscar L; Martinez-Gomez, David

    2015-07-01

    Objetivo: conocer si a aquellos adolescentes que no les gusta la educación física obtienen mejores resultados en rendimiento académico y cognitivo que sus compañeros. Métodos: los participantes incluyen 4.226 adolescentes de los estudios AVENA, AFINOS y UP&DOWN. El gusto por la educación física se valoró con una escala Likert de 7 puntos. El rendimiento cognitivo se valoró en el estudio AVENA usando la versión española del SRA Test of Educational Ability. El rendimiento académico se valoró en los estudios AFINOS y UP&DOWN con las notas de Matemáticas, Lengua y la media de Lengua y Matemáticas. Resultados: en el estudio AVENA encontramos diferencias en la habilidad verbal entre las chicas a las que no les gustaba la educación física y sus compañeros (P = 0,033). En el estudio AFINOS los chicos a los que no les gustaba la educación física tenían mejores notas en Lengua que sus compañeros (P = 0,024). En el estudio UP&DOWN las chicas a las que no les gustaba la educación física obtuvieron mejores resultados en Lengua y en la media de Lengua y Matemáticas (P < 0,001).

  1. Geometric origin of scaling in large traffic networks.

    PubMed

    Popović, Marko; Štefančić, Hrvoje; Zlatić, Vinko

    2012-11-16

    Large scale traffic networks are an indispensable part of contemporary human mobility and international trade. Networks of airport travel and cargo ship movements are invaluable for the understanding of human mobility patterns [R. Guimera et al., Proc. Natl. Acad. Sci. U.S.A. 102, 7794 (2005))], epidemic spreading [V. Colizza et al., Proc. Natl. Acad. Sci. U.S.A. 103, 2015 (2006)], global trade [International Maritime Organization, http://www.imo.org/], and spread of invasive species [G. M. Ruiz et al., Nature (London) 408, 49 (2000)]. Different studies [M. Barthelemy, Phys. Rept. 499, 1 (2011)] point to the universal character of some of the exponents measured in such networks. Here we show that exponents which relate (i) the strength of nodes to their degree and (ii) weights of links to degrees of nodes that they connect have a geometric origin. We present a simple robust model which exhibits the observed power laws and relates exponents to the dimensionality of 2D space in which traffic networks are embedded. We show that the relation between weight strength and degree is s(k)~k(3/2), the relation between distance strength and degree is s(d)(k)~k(3/2), and the relation between weight of link and degrees of linked nodes is w(ij)~(k(i)k(j))(1/2) on the plane 2D surface. We further analyze the influence of spherical geometry, relevant for the whole planet, on exact values of these exponents. Our model predicts that these exponents should be found in future studies of port networks and it imposes constraints on more refined models of port networks.

  2. A proposed essential gene discovery pipeline: a Campylobacter jejuni case study.

    PubMed

    Reuter, Mark; Gaskin, Duncan J H; Metris, Aline

    2015-01-01

    Genes required for an organism's growth and survival are termed essential and represent potential intervention targets. Following in the footsteps of the genomics era, the "next-gen" genomic era provides vast amounts of genetic information. Sequencing of a representative bacterial pathogen genome has been superseded by sequencing of whole strain collections, whether from environmental or clinical sources (Harris et al., Science 327:469-474, 2010; Lewis et al., J Hosp Infect 75:37-41, 2010; Beres et al., Proc Natl Acad Sci U S A 107:4371-4376, 2010; Qi et al., PLoS Pathog 5:e1000580, 2009; He et al., Proc Natl Acad Sci U S A 107:7527-7532, 2010; Barrick et al., Nature 461:1243-1247, 2009; Sheppard et al., Mol Ecol 22:1051-1064, 2013). However, the challenge of using this information to gain biological insight remains. Nonetheless, this information, in combination with experimental data from the literature, can serve as the framework for gaining a better understanding of an organism's biology. Generic metabolic pathways have long been known, and a number of websites (e.g., KEGG and BioCyc) attempt to map information from genome annotation to metabolic pathways (Kanehisa et al., Nucleic Acids Res 40:D109-D114, 2010; Karp et al., Nucleic Acids Res 33:6083-6089, 2005). Extending this analysis to incorporate metabolic flux models further allows in silico prediction of potential essential genes. Such efforts are of value, either to highlight novel generic antimicrobials or to seek novel treatments for non-paradigm organisms. Such in silico approaches are attractive as they can highlight pathways and genes that would otherwise only be identified by costly and time-consuming laboratory methods. PMID:25636619

  3. Mössbauer hyperfine parameters of iron species in the course of Geobacter-mediated magnetite mineralization

    NASA Astrophysics Data System (ADS)

    Li, Yi-Liang; Zhu, San-Yuan; Deng, Kun

    2011-10-01

    Amorphous ferric iron species (ferrihydrite or akaganeite of <5 nm in size) is the only known solid ferric iron oxide that can be reductively transformed by dissimilatory iron-reducing bacteria to magnetite completely. The lepidocrocite crystallite can be transformed into magnetite in the presence of abiotic Fe(II) at elevated pH or biogenic Fe(II) with particular growth conditions. The reduction of lepidocrocite by dissimilatory iron-reducing bacteria has been widely investigated showing varying results. Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004) captured a unique biologically mediated mineralization pathway where the amorphous hydrous ferric oxide transformed to lepidocrocite was followed by the complete reduction of lepidocrocite to single-domain magnetite. Here, we report the 57Fe Mössbauer hyperfine parameters of the time-course samples reported in Vali et al. (Proc Natl Acad Sci USA 101:16121-16126, 2004). Both the quadrupole splittings and linewidths of Fe(III) ions decrease consistently with the change of aqueous Fe(II) and transformations of mineral phases, showing the Fe(II)-mediated gradual regulation of the distorted coordination polyhedrons of Fe3+ during the biomineralization process. The aqueous Fe(II) catalyzes the transformations of Fe(III) minerals but does not enter the mineral structures until the mineralization of magnetite. The simulated abiotic reaction between Fe(II) and lepidocrocite in pH-buffered, anaerobic media shows the simultaneous formation of green rust and its gradual transformation to magnetite plus a small fraction of goethite. We suggested that the dynamics of Fe(II) supply is a critical factor for the mineral transformation in the dissimilatory iron-reducing cultures.

  4. Chemical Analysis of a "Miller-Type" Complex Prebiotic Broth: Part I: Chemical Diversity, Oxygen and Nitrogen Based Polymers.

    PubMed

    Wollrab, Eva; Scherer, Sabrina; Aubriet, Frédéric; Carré, Vincent; Carlomagno, Teresa; Codutti, Luca; Ott, Albrecht

    2016-06-01

    In a famous experiment Stanley Miller showed that a large number of organic substances can emerge from sparking a mixture of methane, ammonia and hydrogen in the presence of water (Miller, Science 117:528-529, 1953). Among these substances Miller identified different amino acids, and he concluded that prebiotic events may well have produced many of Life's molecular building blocks. There have been many variants of the original experiment since, including different gas mixtures (Miller, J Am Chem Soc 77:2351-2361, 1955; Oró Nature 197:862-867, 1963; Schlesinger and Miller, J Mol Evol 19:376-382, 1983; Miyakawa et al., Proc Natl Acad Sci 99:14,628-14,631, 2002). Recently some of Miller's remaining original samples were analyzed with modern equipment (Johnson et al. Science 322:404-404, 2008; Parker et al. Proc Natl Acad Sci 108:5526-5531, 2011) and a total of 23 racemic amino acids were identified. To give an overview of the chemical variety of a possible prebiotic broth, here we analyze a "Miller type" experiment using state of the art mass spectrometry and NMR spectroscopy. We identify substances of a wide range of saturation, which can be hydrophilic, hydrophobic or amphiphilic in nature. Often the molecules contain heteroatoms, with amines and amides being prominent classes of molecule. In some samples we detect ethylene glycol based polymers. Their formation in water requires the presence of a catalyst. Contrary to expectations, we cannot identify any preferred reaction product. The capacity to spontaneously produce this extremely high degree of molecular variety in a very simple experiment is a remarkable feature of organic chemistry and possibly prerequisite for Life to emerge. It remains a future task to uncover how dedicated, organized chemical reaction pathways may have arisen from this degree of complexity.

  5. CNVs leading to fusion transcripts in individuals with autism spectrum disorder

    PubMed Central

    Holt, Richard; Sykes, Nuala H; Conceição, Inês C; Cazier, Jean-Baptiste; Anney, Richard JL; Oliveira, Guiomar; Gallagher, Louise; Vicente, Astrid; Monaco, Anthony P; Pagnamenta, Alistair T

    2012-01-01

    There is strong evidence that rare copy number variants (CNVs) have a role in susceptibility to autism spectrum disorders (ASDs). Much research has focused on how CNVs mediate a phenotypic effect by altering gene expression levels. We investigated an alternative mechanism whereby CNVs combine the 5′ and 3′ ends of two genes, creating a ‘fusion gene'. Any resulting mRNA with an open reading frame could potentially alter the phenotype via a gain-of-function mechanism. We examined 2382 and 3096 rare CNVs from 996 individuals with ASD and 1287 controls, respectively, for potential to generate fusion transcripts. There was no increased burden in individuals with ASD; 122/996 cases harbored at least one rare CNV of this type, compared with 179/1287 controls (P=0.89). There was also no difference in the overall frequency distribution between cases and controls. We examined specific examples of such CNVs nominated by case–control analysis and a candidate approach. Accordingly, a duplication involving REEP1-POLR1A (found in 3/996 cases and 0/1287 controls) and a single occurrence CNV involving KIAA0319-TDP2 were tested. However, no fusion transcripts were detected by RT-PCR. Analysis of additional samples based on cell line availability resulted in validation of a MAPKAPK5-ACAD10 fusion transcript in two probands. However, this variant was present in controls at a similar rate and is unlikely to influence ASD susceptibility. In summary, although we find no evidence that fusion-gene generating CNVs lead to ASD susceptibility, discovery of a MAPKAPK5-ACAD10 transcript with an estimated frequency of ∼1/200 suggests that gain-of-function mechanisms should be considered in future CNVs studies. PMID:22549408

  6. Evidence for an intense solar outburst in prehistory

    NASA Astrophysics Data System (ADS)

    Peratt, A. L.; Yao, W. F.

    2008-10-01

    A past intense solar outburst and its effect on Earth was proposed by Gold (1962 Pontificiae Acad. Sci. Scr. Varia 25 159) who, along with others, based his hypotheses on strong astronomical and geophysical evidence. The discovery that objects from the Neolithic or Early Bronze Age carry patterns associated with high-current Z-pinches, as would result from an intense plasma impinging Earth, provides a possible insight into the origin and meaning of these ancient symbols produced by humans. Peratt (2003 Trans. Plasma Sci. 31 1192) dealt with the comparison of graphical and radiation data from high-current Z-pinches to petroglyphs, geoglyphs and megaliths. Peratt (2007 Trans. Plasma Sci. 35 778) focused primarily, but not exclusively, on petroglyphs of some 84 different morphologies; pictures found in laboratory experiments and carved on rock. These corresponded to mankind's visual observations of ancient aurora as might be produced if the solar wind had increased at times between one and two orders of magnitude, millennia ago (Gold 1962 Pontificiae Acad. Sci. Scr. Varia 25 159). In Peratt (2007 Trans. Plasma Sci. 35 778), the data were given on the source of light and its temporal change from a current-increasing Z-pinch or dense plasma focus aurora. Orientation and field-of-view data are given as surveyed and contributed from 139 countries, from sites and fields containing several millions of these objects, the latest data coming from a 300 km survey along the Orinoco river basin in Venezuela. In this paper, we include additional petroglyph figures derivable from experiment and computer. This information allows a reconstruction of the auroral form presumably associated with extreme geomagnetic storms and shows, based on existent geophysical evidence, relativistic electron flow inward at Earth's south polar axis and hypervelocity proton impacts around the north polar axis.

  7. Anomalous behavior of water inside the SecY translocon.

    PubMed

    Capponi, Sara; Heyden, Matthias; Bondar, Ana-Nicoleta; Tobias, Douglas J; White, Stephen H

    2015-07-21

    The heterotrimeric SecY translocon complex is required for the cotranslational assembly of membrane proteins in bacteria and archaea. The insertion of transmembrane (TM) segments during nascent-chain passage through the translocon is generally viewed as a simple partitioning process between the water-filled translocon and membrane lipid bilayer, suggesting that partitioning is driven by the hydrophobic effect. Indeed, the apparent free energy of partitioning of unnatural aliphatic amino acids on TM segments is proportional to accessible surface area, which is a hallmark of the hydrophobic effect [Öjemalm K, et al. (2011) Proc Natl Acad Sci USA 108(31):E359-E364]. However, the apparent partitioning solvation parameter is less than one-half the value expected for simple bulk partitioning, suggesting that the water in the translocon departs from bulk behavior. To examine the state of water in a SecY translocon complex embedded in a lipid bilayer, we carried out all-atom molecular-dynamics simulations of the Pyrococcus furiosus SecYE, which was determined to be in a "primed" open state [Egea PF, Stroud RM (2010) Proc Natl Acad Sci USA 107(40):17182-17187]. Remarkably, SecYE remained in this state throughout our 450-ns simulation. Water molecules within SecY exhibited anomalous diffusion, had highly retarded rotational dynamics, and aligned their dipoles along the SecY transmembrane axis. The translocon is therefore not a simple water-filled pore, which raises the question of how anomalous water behavior affects the mechanism of translocon function and, more generally, the partitioning of hydrophobic molecules. Because large water-filled cavities are found in many membrane proteins, our findings may have broader implications. PMID:26139523

  8. Chemical Analysis of a "Miller-Type" Complex Prebiotic Broth. Part I: Chemical Diversity, Oxygen and Nitrogen Based Polymers

    NASA Astrophysics Data System (ADS)

    Wollrab, Eva; Scherer, Sabrina; Aubriet, Frédéric; Carré, Vincent; Carlomagno, Teresa; Codutti, Luca; Ott, Albrecht

    2016-06-01

    In a famous experiment Stanley Miller showed that a large number of organic substances can emerge from sparking a mixture of methane, ammonia and hydrogen in the presence of water (Miller, Science 117:528-529, 1953). Among these substances Miller identified different amino acids, and he concluded that prebiotic events may well have produced many of Life's molecular building blocks. There have been many variants of the original experiment since, including different gas mixtures (Miller, J Am Chem Soc 77:2351-2361, 1955; Oró Nature 197:862-867, 1963; Schlesinger and Miller, J Mol Evol 19:376-382, 1983; Miyakawa et al., Proc Natl Acad Sci 99:14,628-14,631, 2002). Recently some of Miller's remaining original samples were analyzed with modern equipment (Johnson et al. Science 322:404-404, 2008; Parker et al. Proc Natl Acad Sci 108:5526-5531, 2011) and a total of 23 racemic amino acids were identified. To give an overview of the chemical variety of a possible prebiotic broth, here we analyze a "Miller type" experiment using state of the art mass spectrometry and NMR spectroscopy. We identify substances of a wide range of saturation, which can be hydrophilic, hydrophobic or amphiphilic in nature. Often the molecules contain heteroatoms, with amines and amides being prominent classes of molecule. In some samples we detect ethylene glycol based polymers. Their formation in water requires the presence of a catalyst. Contrary to expectations, we cannot identify any preferred reaction product. The capacity to spontaneously produce this extremely high degree of molecular variety in a very simple experiment is a remarkable feature of organic chemistry and possibly prerequisite for Life to emerge. It remains a future task to uncover how dedicated, organized chemical reaction pathways may have arisen from this degree of complexity.

  9. Metabolic Heritability at Birth: Implications for Chronic Disease Research

    PubMed Central

    Ryckman, Kelli K.; Smith, Caitlin J.; Jelliffe-Pawlowski, Laura L; Momany, Allison M.; Berberich, Stanton L.; Murray, Jeffrey C.

    2014-01-01

    Recent genome-wide association studies of the adult human metabolome have identified genetic variants associated with relative levels of several acylcarnitines, which are important clinical correlates for chronic conditions such as type 2 diabetes and obesity. We have previously shown that these same metabolite levels are highly heritable at birth; however, no studies to our knowledge have examined genetic associations with these metabolites measured at birth. Here, we examine, in 743 newborns, 58 single nucleotide polymorphisms (SNPs) in 11 candidate genes previously associated with differing relative levels of short-chain acylcarnitines in adults. Six SNPs (rs2066938, rs3916, rs3794215, rs555404, rs558314, rs1799958) in the short chain acyl-CoA dehydrogenase gene (ACADS) were associated with neonatal C4 levels. Most significant was the G allele of rs2066938, which was associated with significantly higher levels of C4 (P=1.5×10−29). This SNP explains 25% of the variation in neonatal C4 levels, which is similar to the variation previously reported in adult C4 levels. There were also significant (P<1×10−4) associations between neonatal levels of C5-OH and SNPs in the solute carrier family 22 genes (SLC22A4 and SLC22A5) and the 3-methylcrotonyl-CoA carboxylase 1 gene (MCCC1). We have replicated, in newborns, SNP associations between metabolic traits and the ACADS and SLC22A4 genes observed in adults. This research has important implications not only for the identification of rare inborn errors of metabolism but also for personalized medicine and early detection of later life risks for chronic conditions. PMID:24850141

  10. Metabolic heritability at birth: implications for chronic disease research.

    PubMed

    Ryckman, Kelli K; Smith, Caitlin J; Jelliffe-Pawlowski, Laura L; Momany, Allison M; Berberich, Stanton L; Murray, Jeffrey C

    2014-08-01

    Recent genome-wide association studies of the adult human metabolome have identified genetic variants associated with relative levels of several acylcarnitines, which are important clinical correlates for chronic conditions such as type 2 diabetes and obesity. We have previously shown that these same metabolite levels are highly heritable at birth; however, no studies to our knowledge have examined genetic associations with these metabolites measured at birth. Here, we examine, in 743 newborns, 58 single nucleotide polymorphisms (SNPs) in 11 candidate genes previously associated with differing relative levels of short-chain acylcarnitines in adults. Six SNPs (rs2066938, rs3916, rs3794215, rs555404, rs558314, rs1799958) in the short-chain acyl-CoA dehydrogenase gene (ACADS) were associated with neonatal C4 levels. Most significant was the G allele of rs2066938, which was associated with significantly higher levels of C4 (P = 1.5 × 10(-29)). This SNP explains 25 % of the variation in neonatal C4 levels, which is similar to the variation previously reported in adult C4 levels. There were also significant (P < 1 × 10(-4)) associations between neonatal levels of C5-OH and SNPs in the solute carrier family 22 genes (SLC22A4 and SLC22A5) and the 3-methylcrotonyl-CoA carboxylase 1 gene (MCCC1). We have replicated, in newborns, SNP associations between metabolic traits and the ACADS and SLC22A4 genes observed in adults. This research has important implications not only for the identification of rare inborn errors of metabolism but also for personalized medicine and early detection of later life risks for chronic conditions.

  11. The origin of the supernumerary subunits and assembly factors of complex I: A treasure trove of pathway evolution.

    PubMed

    Elurbe, Dei M; Huynen, Martijn A

    2016-07-01

    We review and document the evolutionary origin of all complex I assembly factors and nine supernumerary subunits from protein families. Based on experimental data and the conservation of critical residues we identify a spectrum of protein function conservation between the complex I representatives and their non-complex I homologs. This spectrum ranges from proteins that have retained their molecular function but in which the substrate specificity may have changed or have become more specific, like NDUFAF5, to proteins that have lost their original molecular function and critical catalytic residues like NDUFAF6. In between are proteins that have retained their molecular function, which however appears unrelated to complex I, like ACAD9, or proteins in which amino acids of the active site are conserved but for which no enzymatic activity has been reported, like NDUFA10. We interpret complex I evolution against the background of molecular evolution theory. Complex I supernumerary subunits and assembly factors appear to have been recruited from proteins that are mitochondrial and/or that are expressed when complex I is active. Within the evolution of complex I and its assembly there are many cases of neofunctionalization after gene duplication, like ACAD9 and TMEM126B, one case of subfunctionalization: ACPM1 and ACPM2 in Yarrowia lipolytica, and one case in which a complex I protein itself appears to have been the source of a new protein from another complex: NDUFS6 gave rise to cytochrome c oxidase subunit COX4/COX5b. Complex I and its assembly can therewith be regarded as a treasure trove for pathway evolution. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt.

  12. Inactivation of Escherichia coli glutamine synthetase by xanthine oxidase, nicotinate hydroxylase, horseradish peroxidase, or glucose oxidase: effects of ferredoxin, putidaredoxin, and menadione.

    PubMed

    Stadtman, E R; Wittenberger, M E

    1985-06-01

    Previous studies have shown that several mixed-function oxidation (MFO) systems are capable of catalyzing the inactivation of glutamine synthetase (GS) [R.L. Levine, C. N. Oliver, R. M. Fulks, and E. R. Stadtman (1978) Proc. Natl. Acad. Sci. USA 78, 2120-2124] and a number of the other enzymes [L. Fucci, C. N. Oliver, M. J. Coon, and E. R. Stadtman (1983) Proc. Natl. Acad. Sci. USA 80, 1521-1525]. It has now been found that in the presence of Fe(III), O2, and an appropriate electron donor (hypoxanthine or NADPH, respectively) glutamine synthetase is also inactivated by either milk xanthine oxidase or Clostridial nicotinate hydroxylase. Inactivation of glutamine synthetase by either of these flavoproteins is greatly stimulated by the presence of electron carrier proteins possessing nonheme-iron-sulfur (NHIS) clusters (i.e., ferredoxin or putidaredoxin) or by the presence of menadione. The inactivation reactions are partially inhibited by free radical scavengers, superoxide dismutase, (SOD), histidine, mannitol, dimethyl sulfoxide, and dimethylthiourea, and are inhibited completely by either Mn(II), EDTA, or catalase. The sensitivity to SOD inhibition is greatly suppressed when the xanthine oxidase system is supplemented with either ferredoxin or redoxin. In the presence of the latter NHIS-proteins (and only when they are present), MFO systems, comprised of either horseradish peroxidase and H2O2 or glucose oxidase, O2, and glucose, can also catalyze the inactivation of GS. The ability of ferredoxin and putidaredoxin to promote oxidation modification of GS by any one of these MFO systems suggests that proteins with NHIS centers may mediate the generation (or stabilization) of highly reactive radical intermediates.

  13. Inactivation of enzymes and oxidative modification of proteins by stimulated neutrophils.

    PubMed

    Oliver, C N

    1987-02-15

    Differentiated, stimulated HL-60 cells and freshly isolated, stimulated neutrophils inactivate glutamine synthetase (L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2) either inside or outside of Escherichia coli. Stimulated neutrophils also inactivate at least four endogenous enzymes which are inactivated by mixed-function oxidation (MFO) systems in vitro (L. Fucci, C.N. Oliver, M.J. Coon, and E.R. Stadtman (1983) Proc. Natl. Acad. Sci. USA 80, 1521-1525). The inactivation of glutamine synthetase by stimulated neutrophils exhibits characteristics similar to those previously described using both enzymic and nonenzymic MFO systems (R.L. Levine, C.N. Oliver, R.M. Fulks, and E.R. Stadtman (1981) Proc. Natl. Acad. Sci. USA 78, 2120-2124). Although the reaction occurs in the absence of Fe(III), it is stimulated by added Fe (III). Inactivation required molecular oxygen and is partially inhibited by Mn(II), catalase, superoxide dismutase, and metal chelators, ethylenediaminetetraacetic acid and o-phenanthroline. Both the kinetics and the extent of glutamine synthetase inactivation differ when neutrophils are stimulated with phorbol esters compared with formylated peptides. Glutamine synthetase inactivation catalyzed by MFO systems is accompanied by the formation of protein carbonyl derivatives which form stable hydrazones when treated with 2,4-dinitrophenylhydrazine. Multiple carbonyl derivatives are formed in the soluble protein fraction of stimulated neutrophils and these derivatives collectively exhibit an absorbance spectrum similar to that of glutamine synthetase inactivated by liver microsomal cytochrome P-450 MFO system (K. Nakamura, C.N. Oliver, and E.R. Stadtman (1985) Arch. Biochem. Biophys. 240, 319-329).

  14. Study of minima of the fluctuations of the order parameter of seismicity using GCMT catalogue in global scale.

    NASA Astrophysics Data System (ADS)

    Christopoulos, Stavros-Richard G.; Sarlis, Nicholas V.; Skordas, Efthimios S.

    2016-04-01

    It has been recently shown [1,2] that earthquakes of magnitude M greater or equal to 7 are globally correlated. The identification of this correlation became possible when studying the variance κ1 of natural time which has been proposed as an order parameter for seismicity[3,4]. In the present study, we focus on the behaviour of the fluctuations of κ1 before major earthquakes using the Global Centroid Moment Tensor catalogue for a magnitude threshold Mthres=5.0 as in Ref.[5]. Natural time analysis reveals that distinct minima of the fluctuations κ1of seismicity appear within almost five and a half months on average before all major earthquakes of magnitude larger than M8.4. This phenomenon corroborates the recent finding [6] that similar minima of seismicity order parameter fluctuations had been observed before all major shallow earthquakes in Japan. Finally, we examine the statistical significance of the results by using ROC graphs [7,8] and the proposed prediction method has a p-value to occur by chance well below 0.1%. The hit rate is 100% with a false alarm rate only 6.67%. An attempt to lower the target earthquake magnitude threshold will be also presented. REFERENCES [1] N. V. Sarlis, Phys. Rev. E 84, 022101 (2011). [2] N. V. Sarlis and S.-R. G. Christopoulos, Chaos 22, 023123 (2012) [3] P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, Practica of Athens Acad. 76, 294 (2001). [4] P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, Phys. Rev. E 66, 011902 (2002). [5] N.V. Sarlis, S.-R. G. Christopoulos, and E. S. Skordas, Chaos 25, 063110 (2015) [6] N. V. Sarlis et al., Proc. Natl. Acad. Sci. U.S.A. 110, 13734 (2013) [7] T. Fawcett, Pattern Recognit. Lett. 27, 861 (2006). [8] N. V. Sarlis and S.-R. G. Christopoulos, Comput. Phys. Commun. 185, 1172 (2014).

  15. Hydrophobic effect in protein folding and other noncovalent processes involving proteins.

    PubMed Central

    Spolar, R S; Ha, J H; Record, M T

    1989-01-01

    Large negative standard heat capacity changes (delta CP degree much less than 0) are the hallmark of processes that remove nonpolar surface from water, including the transfer of nonpolar solutes from water to a nonaqueous phase and the folding, aggregation/association, and ligand-binding reactions of proteins [Sturtevant, J. M. (1977) Proc. Natl. Acad. Sci. USA 74, 2236-2240]. More recently, Baldwin [Baldwin, R. L. (1986) Proc. Natl. Acad. Sci. USA 83, 8069-8072] proposed that the delta CP degree of protein folding could be used to quantify the contribution of the burial of nonpolar surface (the hydrophobic effect) to the stability of a globular protein. We demonstrate that identical correlations between the delta CP degree and the change in water-accessible nonpolar surface area (delta Anp) are obtained for both the transfer of nonpolar solutes from water to the pure liquid phase and the folding of small globular proteins: delta CP degree/delta Anp = -(0.28 +/- 0.05) (where delta Anp is expressed in A2 and delta CP degree is expressed in cal.mol-1.K-1; 1 cal = 4.184 J). The fact that these correlations are identical validates the proposals by both Sturtevant and Baldwin that the hydrophobic effect is in general the dominant contributor to delta CP degree and provides a straightforward means of estimating the contribution of the hydrophobic driving force (delta Ghyd degree) to the standard free energy change of a noncovalent process characterized by a large negative delta CP degree in the physiological temperature range: delta Ghyd degree congruent to (80 +/- 10)delta CP degree. PMID:2813394

  16. U1 snRNA as an effective vector for stable expression of antisense molecules and for the inhibition of the splicing reaction.

    PubMed

    Martone, Julie; De Angelis, Fernanda Gabriella; Bozzoni, Irene

    2012-01-01

    We report the use of the U1 snRNA as a vector for the stable expression of antisense molecules against the splice junctions of specific dystrophin exons. The single-stranded 5' terminus of U1 can be replaced by unrelated sequences as long as 50 nucleotides without affecting both the stability and the ability to assemble into snRNP particles. Effective exon skipping has been obtained for different dystrophin exons by antisense sequences against 5' and 3' splice sites alone or in combination with ESE sequences. The efficacy of these molecules has been studied both in in vitro systems and in animals. In both cases the chimeric molecules, delivered as part of lentiviral or AAV vectors (De Angelis et al. Proc Natl Acad Sci USA 99:9456-9461, 2002; Denti et al. Proc Natl Acad Sci USA 103: 3758-3763, 2006; Denti et al. Hum Gene Ther 17: 565-743, 2006; Denti et al. Hum Gene Ther 19: 601-608, 2008; Incitti et al. Mol Ther 18: 1675-1682, 2010), provided high skipping activity and efficient rescue of dystrophin synthesis. Moreover, the U1-antisense molecules, delivered to mice via systemic injection of recombinant AAV viruses, displayed body wide transduction, long-term expression, dystrophin rescue as well as morphological and functional benefit (Denti et al. Hum Gene Ther 19: 601-608, 2008). In this Chapter we report methods for producing U1-antisense expression cassettes in the backbone of lentiviral constructs and for testing their activity both in patients' derived myoblasts as well as in fibroblasts reprogrammed to muscle differentiation.

  17. Deep Sequencing Reveals Novel Genetic Variants in Children with Acute Liver Failure and Tissue Evidence of Impaired Energy Metabolism

    PubMed Central

    Valencia, C. Alexander; Wang, Xinjian; Wang, Jin; Peters, Anna; Simmons, Julia R.; Moran, Molly C.; Mathur, Abhinav; Husami, Ammar; Qian, Yaping; Sheridan, Rachel; Bove, Kevin E.; Witte, David; Huang, Taosheng; Miethke, Alexander G.

    2016-01-01

    Background & Aims The etiology of acute liver failure (ALF) remains elusive in almost half of affected children. We hypothesized that inherited mitochondrial and fatty acid oxidation disorders were occult etiological factors in patients with idiopathic ALF and impaired energy metabolism. Methods Twelve patients with elevated blood molar lactate/pyruvate ratio and indeterminate etiology were selected from a retrospective cohort of 74 subjects with ALF because their fixed and frozen liver samples were available for histological, ultrastructural, molecular and biochemical analysis. Results A customized next-generation sequencing panel for 26 genes associated with mitochondrial and fatty acid oxidation defects revealed mutations and sequence variants in five subjects. Variants involved the genes ACAD9, POLG, POLG2, DGUOK, and RRM2B; the latter not previously reported in subjects with ALF. The explanted livers of the patients with heterozygous, truncating insertion mutations in RRM2B showed patchy micro- and macrovesicular steatosis, decreased mitochondrial DNA (mtDNA) content <30% of controls, and reduced respiratory chain complex activity; both patients had good post-transplant outcome. One infant with severe lactic acidosis was found to carry two heterozygous variants in ACAD9, which was associated with isolated complex I deficiency and diffuse hypergranular hepatocytes. The two subjects with heterozygous variants of unknown clinical significance in POLG and DGUOK developed ALF following drug exposure. Their hepatocytes displayed abnormal mitochondria by electron microscopy. Conclusion Targeted next generation sequencing and correlation with histological, ultrastructural and functional studies on liver tissue in children with elevated lactate/pyruvate ratio expand the spectrum of genes associated with pediatric ALF. PMID:27483465

  18. Benzene and human health: A historical review and appraisal of associations with various diseases.

    PubMed

    Galbraith, David; Gross, Sherilyn A; Paustenbach, Dennis

    2010-11-01

    Over the last century, benzene has been a well-studied chemical, with some acute and chronic exposures being directly associated with observed hematologic effects in humans and animals. Chronic heavy exposures to benzene have also been associated with acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) in humans. Other disease processes have also been studied, but have generally not been supported by epidemiologic studies of workers using benzene in the workplace. Within occupational cohorts with large populations and very low airborne benzene exposures (less than 0.1–1.0 ppm), it can be difficult to separate background disease incidence from those occurring due to occupational exposures. In the last few decades, some scientists and physicians have suggested that chronic exposures to various airborne concentrations of benzene may increase the risk of developing non-Hodgkin's lymphoma (NHL) (Savitz and Andrews, 1997, Am J Ind Med 31:287–295; Smith et al., 2007, Cancer Epidemiol Biomarkers Prev 16:385–391), multiple myeloma (MM) (Goldstein, 1990, Ann NY Acad Sci 609:225–230; Infante, 2006, Ann NY Acad Sci 1076:90–109), and various other hematopoietic disorders. We present a state-of-the-science review of the medical and regulatory aspects regarding the hazards of occupational exposure to benzene. We also review the available scientific and medical evidence relating to benzene and the risk of developing various disorders following specific levels of exposure. Our evaluation indicates that the only malignant hematopoietic disease that has been clearly linked to benzene exposure is AML. Information from the recent "Benzene 2009," a symposium of international experts focusing on the health effects and mechanisms of toxicity of benzene, hosted by the Technical University of Munich, has been incorporated and referenced.

  19. Bone Tissue Response to Porous and Functionalized Titanium and Silica Based Coatings

    PubMed Central

    Chaudhari, Amol; Braem, Annabel; Vleugels, Jozef; Martens, Johan A.; Naert, Ignace; Cardoso, Marcio Vivan; Duyck, Joke

    2011-01-01

    Background Topography and presence of bio-mimetic coatings are known to improve osseointegration. The objective of this study was to evaluate the bone regeneration potential of porous and osteogenic coatings. Methodology Six-implants [Control (CTR); porous titanium coatings (T1, T2); thickened titanium (Ti) dioxide layer (TiO2); Amorphous Microporous Silica (AMS) and Bio-active Glass (BAG)] were implanted randomly in tibiae of 20-New Zealand white rabbits. The animals were sacrificed after 2 or 4 weeks. The samples were analyzed histologically and histomorphometrically. In the initial bone-free areas (bone regeneration areas (BRAs)), the bone area fraction (BAF) was evaluated in the whole cavity (500 µm, BAF-500), in the implant vicinity (100 µm, BAF-100) and further away (100–500 µm, BAF-400) from the implant. Bone-to-implant contact (BIC-BAA) was measured in the areas where the implants were installed in contact to the host bone (bone adaptation areas (BAAs)) to understand and compare the bone adaptation. Mixed models were used for statistical analysis. Principal Findings After 2 weeks, the differences in BAF-500 for different surfaces were not significant (p>0.05). After 4 weeks, a higher BAF-500 was observed for BAG than CTR. BAF-100 for AMS was higher than BAG and BAF-400 for BAG was higher than CTR and AMS. For T1 and AMS, the bone regeneration was faster in the 100-µm compared to the 400-µm zone. BIC-BAA for AMS and BAG was lower after 4 than 2 weeks. After 4 weeks, BIC-BAA for BAG was lower than AMS and CTR. Conclusions BAG is highly osteogenic at a distance from the implant. The porous titanium coatings didn't stimulate bone regeneration but allowed bone growth into the pores. Although AMS didn't stimulate higher bone response, it has a potential of faster bone growth in the vicinity compared to further away from the surface. BIC-BAA data were inconclusive to understand the bone adaptation. PMID:21935382

  20. Using Uranium-Series Isotopes to Quantify Volcanic Soil Formation Rates Under a Tropical Climate: Basse-Terre, Guadeloupe

    NASA Astrophysics Data System (ADS)

    Pereyra, Y.; Ma, L.; Sak, P. B.; Gaillardet, J.; Buss, H. L.; Brantley, S. L.

    2014-12-01

    U-series isotopes fractionate during chemical weathering and their activity ratios have been used to determine timescales and rates of soil formation. Such soil formation rates are measured at soil profile scale and provide an important link to compare chemical weathering rates measured across different spatial scales. We analyzed U-series isotope compositions in a ~12m deep soil profile in Basse-Terre Island of French Guadeloupe. The tropical Bras David watershed is developed on andesitic pyroclastic flows. Field observations have shown heterogeneity in color and texture in this profile. However, major element chemistry and mineralogy show some general depth trends. First, Al, Fe, and Ti show a depletion profile relative to Th from 12m to 4m depth, an addition from 4m to 2m, and depletion from 2m to the surface. Second, mobile elements such as Ca, Mg, and Sr have undergone intensive weathering, therefore show almost complete depletion even in the deep profile, and an addition profile near the surface. This addition trend is most likely related to atmospheric dust and marine aerosol signatures. Finally, K, Mn, and Si show a partial depletion profile at depth. The main minerals present throughout the soil profile are halloysite and gibbsite. 238U/232Th ratios in this profile ranged from 0.374 to 1.696, while the 230Th/232Th ratios ranged from 0.367 to 1.701. A decrease of (238U/232Th) in the deep soil profile from 12m to 4m depth is observed, and an increase in the shallow profile from 4m to the surface. The (230Th /232Th) ratios showed a similar trend as (238U/232Th). Marine aerosols and atmospheric dust are responsible for the addition of U in shallow soils while intensive chemical weathering is responsible for the loss of U at depth. U-series chemical weathering model suggests that the weathering duration from 12m to 4m depth is about 250kyr, with a weathering advancing rate of ~30 m/Ma. The rate is also about one order of magnitude lower than the weathering rate

  1. Hydrological changes due to land-use change from Brazilian savanna to managed Eucalyptus

    NASA Astrophysics Data System (ADS)

    Siqueira, M. B.; Mota, F. C. M.

    2014-12-01

    Before the large people influx and development of the central part of Brazil in the sixties, due to new capital Brasília, Cerrado, a typical Brazilian savanna-type vegetation, used to occupy about 2 million km2, going from the Amazon tropical forest, in the north, to the edges of what used to be the Atlantic forest in the southeast. Today, somewhat 50% of this area has given place to agriculture, pasture and managed forests. Understanding how Cerrado interacts with the atmosphere and how this interaction will be modified with this land-use change is a crucial step towards improving predictions of future climate-change scenarios. Cerrado is a vegetation adapted to a climate characterized by two distinct seasons, a wet season (Nov-Mar) and dry season (May-Ago), with April and October being transitions between seasons. Typically, 75% of precipitation happens in the wet-season months and only 5% during dry-season. In this study, it is investigated the potential impacts of the substitution of Cerrado to the eco-hydrological characteristics of the region. The focus here is Eucalyptus plantation which have increased substantially in the last decade due to government incentives. Two eddy-covariance (EC) systems were installed, one in an undisturbed Cerrado Stricto area and other in a recently-established Eucalyptus plantation. The two areas are 1,400m apart and are subjected to the same meteorology and similar edaphic conditions. Besides instrumentation typical of EC towers, a soil-moisture profiling system were installed in each site. Data from the towers will be used to parameterized a Soil-Vegetation-Atmosphere (SVAT) model to simulate hydrological and atmospheric boundary layer (ABL) processes in order to understand how the two vegetation cover modulates the exchange of mass and energy between the biosphere and atmosphere. Simulations of 30-day dry down from saturation to complete water stress were performed and were analyzed on how ABL respond to soil moisture

  2. Processus mis en jeu dans l'evolution morpho-dynamique de Roberts Bank (Delta du Fraser): Observation et modelisation hydrodynamiques et sedimentaires

    NASA Astrophysics Data System (ADS)

    Meule, Samuel

    Roberts Bank couvre le delta intertidal entre le bras principal du fleuve Fraser et la pointe du Cap Roberts en Colombie Britannique, Canada. Sous la pression du developpement urbain et la modification du regime sedimentaire, cette plage de sable fin est soumise a une erosion significative. L'identification des forces hydrodynamiques, leur importance et leur interaction permettent de determiner les zones de transport, et donc la stabilite de Roberts Bank. Deux periodes de mesures associees a des phases de modelisation de la houle et des courants ont ete effectuees lors de ce travail. La premiere periode de mesure, entre le 29 juin et le 8 juillet 2001, a permis l'identification de processus hydrodynamiques et sedimentaires associes aux forts courants de maree presents le long de Roberts Bank. La seconde phase de mesure, entre le 1er mars et le 26 mars 2002, a permis d'etudier les processus de remise en suspension associes a la houle. Des phases de modelisation ont ete menees a partir des connaissances acquises sur le terrain, afin d'affiner la comprehension des processus sedimentaires et notamment les interactions houle - courant - sediment. Les mecanismes, mis en evidence dans cette etude, participent au faconnage de Roberts Bank, contribuent a son erosion et a la mise en place de nouvelles structures sedimentaires. Les courants de flot de maree vont initier la creation de nuages de resuspension de sediment depuis le fond. En eau peu profonde, la composante " onshore" du courant de maree induit un transport a la cote, tandis qu'en eau plus profonde une faible composante " offshore" du courant peut favoriser un transport au large le long de la pente. Les chenaux, les dunes subaquatiques et les surfaces d'erosion affleurantes fournissent une rugosite de fond suffisante a la generation de turbulence et donc de nuages de sediment en suspension. Lors de la maree de jusant, les sediments resuspendus en eau peu profonde, sont transportes vers le large a partir d

  3. Development and testing of a bank erosion modelling tool for informing catchment management

    NASA Astrophysics Data System (ADS)

    Janes, V.; Nicholas, A.; Collins, A.; Quine, T. A.

    2011-12-01

    migration rates was investigated using existing meander migration models (e.g., Howard and Knutson, 1984; Lancaster and Bras, 2002). Model outputs were compared to the observed channel evolution from GIS and regression relationships. The migration models and GIS data were then used to investigate the relationship between channel sinuosity and bank erosion further. It was noted that this relationship is linear up to a threshold value, at which point bank erosion rate does not increase with an additional increase in channel sinuosity. An index incorporating factors observed to have significant influence on bank erosion rates from the research was developed. The performance of the bank erosion index was then evaluated against GIS data. This index out-performs existing modelling approaches and seeks to incorporate the key physical controls on bank erosion, hence it is expected that it will have wide applicability in catchment- to national-scale bank erosion assessment.

  4. Pilomatricome: étude de 22 cas

    PubMed Central

    Nasreddine, Fatima Zahra; Hali, Fouzia; Chiheb, Soumiya

    2016-01-01

    Le pilomatricome est une tumeur cutanée fréquente et bénigne du follicule pileux chez l'enfant. C'est une tumeur annexielle souvent méconnue et confondue avec d'autres lésions cutanées. Les localisations habituelles sont la tête et le cou. Le but de ce travail est de rapporter une série de 22 cas comportant des formes inhabituelles colligées au service de dermatologie sur une période allant de Janvier 2006 jusqu'au Mai 2015. L’étude a concerné 16 femmes et 6 hommes. La moyenne d’âge était de 23,3 ans (4-80 ans). La localisation cervico faciale a été observée dans 12 cas, 2 patients avaient des localisations multiples, un garçon de 4ans avait une localisation au niveau fronto-temporal et une fillette de 14 ans avait une localisation au niveau du visage et de l'avant-bras, et un patient de 48 ans avait une localisation sous unguéale. L'aspect clinique était typique dans tous les cas avec des nodules sous cutanés de consistance pierreuse. Tous les patients ont bénéficié d'une exérèse des nodules sous anesthésie locale. L’étude histologique était en faveur d'un épithélioma momifié de Malherbe d'exérèse complète sans signes de malignité. Aucun patient n'a présenté de rechute. L'originalité de notre étude réside dans la présence de localisations exceptionnelles au niveau latéro-vertébral, des membres et sous-unguéale, l’âge de survenue inhabituel à 80 ans et la présence de localisations multiples signalées chez 2 enfants. PMID:27516819

  5. The Experience Of The Meteorological Support By The National Institute Of Meteorology During The XV Pan-american Games

    NASA Astrophysics Data System (ADS)

    Seabra, M.; Gonçalves, P.; Braga, A.; Raposo, R.; Ito, E.; Gadelha, A.; Dallantonia, A.

    2008-05-01

    The XV Pan-American Games were organized in Rio de Janeiro city during 13 to 29 July, 2007 with a participation of 5.662 athletes of 42 countries . The Ministry of Sports requested INMET to provide meteorological support to the games, with the exception of the water sports only, which fell under the responsibility of the Brazilian Navy. The meteorological activities should follow the same pattern experienced during the Olympic Games of Sydney in Australia in the year of 2000, and of Athens in Greece in 2004, with a forecast center entirely dedicated to the event. NMET developed a website with detailed information oriented to the athletes and organizing committee and to the general public. The homepage had 3 different option of idioms (Portuguese, English and Spanish). After choosing the idiom, the user could consult the meteorological data, to each competition place, and to the Pan- American Village, every 15 minutes, containing weather forecast bulletin, daily synoptic analysis, the last 10 satellite image and meteograms. Besides observed data verified "in situ" INMET supplied forecast generated by High Resolution Model (MBAR) with 7km grid resolution especially set up for the games. INMET installed 7 automatic meteorological stations near the competition places, which supplied temperature , relative humidity , atmospheric pressure, wind (direction and intensity), radiation and precipitation every 15 minutes. Those information were relayed by satellite to INMET headquarters located in Brasília and soon after they were published in the website. To help the Brazilian Olympic Committee - COB, the athletes, their technical commission and the public in general, meteorological bulletins were emitted daily. The forecast was done together with the Navy and also with INMET's 6th District located in Rio de Janeiro, and responsible for the forecast statewide. This forecast was then placed at the INMET's website. Both the 3 days weather forecast and Meteorological Alert were

  6. Great Historical Events That Were Significantly Affected by the Weather. Part 11: Meteorological Aspects of the Battle of Waterloo.

    NASA Astrophysics Data System (ADS)

    Neumann, J.

    1993-03-01

    The Waterloo Campaign extended from 15 to 18 June 1815, with the decisive Battle of Waterloo taking place on the 18th. The campaign involved the "Army of the North" of Napoleon on the one hand, and the Anglo-Dutch and Prussian armies on the other. The latter were commanded, respectively, by the Duke of Wellington and Prince Blücher. A shallow but active low and associated warm and cold fronts crossed the battle area on the 16th and 17th.The weather had important effects on the battles. On the 16th, in a battle between part of the French army and part of the Prussian army, at the village of Ligny, about 40 km south-southeast of Brussels, thunderstorms connected with the passage of the aforementioned warm front made the use of muskets impracticable.However, the most important weather effects developed on the 17th and during the night from the 17th to the 18th. Violent thunderstorms occurred early in the afternoon of the 17th close to Ligny, while Napoleon was in the process of attacking the Anglo-Dutch force at Quatre Bras. The rains turned the ground into a quagmire, making it impossible for the French artillery and cavalry, and even for the infantry, to move across the fields in extended order, as required by the emperor. The French advance was so greatly slowed down that Wellington was able to withdraw his lighter force to a better position near Waterloo. Thus, the Anglo-Dutch force was almost completely preserved for the decisive battle of the next day.The rainshowers of the 17th and the night from the 17th to the 18th softened the ground to an extent that, on the morning of the 18th, Napoleon and his artillery experts judged that the battle-the Battle of Waterloo-could not be started before a late hour of the forenoon [1130 local standard time (LST)]. Until the arrival of the Prussian force, about 1600 LST and later, the battle tended to go in favor of the French, but the Prussians turned the tide of the fighting.The paper quotes judgments of military

  7. Interactions between soil moisture and Atmospheric Boundary Layer at the Brazilian savana-type vegetation Cerrado

    NASA Astrophysics Data System (ADS)

    Pinheiro, L. R.; Siqueira, M. B.

    2013-05-01

    Before the large people influx and development of the central part of Brazil in the sixties, due to new capital Brasília, Cerrado, a typical Brazilian savanna-type vegetation, used to occupy about 2 million km2, going all the way from the Amazon tropical forest, in the north of the country, to the edges of what used to be of the Atlantic forest in the southeast. Today, somewhat 50% of this area has given place to agriculture, pasture and managed forests. It is forecasted that, at the current rate of this vegetation displacement, Cerrado will be gone by 2030. Understanding how Cerrado interacts with the atmosphere and how this interaction will be modified with this land-use change is a crucial step towards improving predictions of future climate-change scenarios. Cerrado is a vegetation adapted to a climate characterized by two very distinct seasons, a wet season (Nov-Mar) and dry season (May-Ago), with April and October being transitions between seasons. Typically, based on measurements in a weather station located in Brasilia, 75% of precipitation happens in the wet-season months and only 5% during dry-season. Under these circumstances, it is clear that the vegetation will have to cope with long periods of water stress. In this work we studied using numerical simulations, the interactions between soil-moisture, responsible for the water stress, with the Atmospheric Boundary Layer (ABL). The numerical model comprises of a Soil-Vegetation-Atmosphere model where the biophysical processes are represented with a big-leaf approach. Soil water is estimated with a simple logistic model and with water-stress effects on stomatal conductance are parameterized from local measurements of simultaneous latent-heat fluxes and soil moisture. ABL evolution is calculate with a slab model that considers independently surface and entrainment fluxes of sensible- and latent- heat. Temperature tropospheric lapse-rate is taken from soundings at local airport. Simulations of 30-day dry

  8. Impacts of Dust on Tropical Volcanic Soil Formation: Insights from Strontium and Uranium-Series Isotopes in Soils from Basse-Terre Island, French Guadeloupe

    NASA Astrophysics Data System (ADS)

    Pereyra, Y.; Ma, L.; Sak, P. B.; Gaillardet, J.; Buss, H. L.; Brantley, S. L.

    2015-12-01

    Dust inputs play an important role in soil formation, especially for thick soils developed on tropical volcanic islands. In these regions, soils are highly depleted due to intensive chemical weathering, and mineral nutrients from dusts have been known to be important in sustaining soil fertility and productivity. Tropical volcanic soils are an ideal system to study the impacts of dust inputs on the ecosystem. Sr and U-series isotopes are excellent tracers to identify sources of materials in an open system if the end-members have distinctive isotope signatures. These two isotope systems are particularly useful to trace the origin of atmospheric inputs into soils and to determine rates and timescales of soil formation. This study analyzes major elemental concentrations, Sr and U-series isotope ratios in highly depleted soils in the tropical volcanic island of Basse-Terre in French Guadeloupe to determine atmospheric input sources and identify key soil formation processes. We focus on three soil profiles (8 to 12 m thick) from the Bras-David, Moustique Petit-Bourg, and Deshaies watersheds; and on the adjacent rivers to these sites. Results have shown a significant depletion of U, Sr, and major elements in the deep profile (12 to 4 m) attributed to rapid chemical weathering. The top soil profiles (4 m to the surface) all show addition of elements such as Ca, Mg, U, and Sr due to atmospheric dust. More importantly, the topsoil profiles have distinct Sr and U-series isotope compositions from the deep soils. Sr and U-series isotope ratios of the top soils and sequential extraction fractions confirm that the sources of the dust are from the Saharan dessert, through long distance transport from Africa to the Caribbean region across the Atlantic Ocean. During the transport, some dust isotope signatures may also have been modified by local volcanic ashes and marine aerosols. Our study highlights that dusts and marine aerosols play important roles in element cycles and

  9. Application of Geographical Information System Arc/info Grid-Based Surface Hyrologic Modeling to the Eastern Hellas Region, Mars

    NASA Astrophysics Data System (ADS)

    Mest, S. C.; Harbert, W.; Crown, D. A.

    2001-05-01

    watersheds derived using this methodology. Mest, Scott C., Crown, David A., and Harbert, William, 2001, Highland drainage basins and valley networks in the eastern Hellas Region of Mars, Abstract 1419, Lunar and Planetary Science XXXII Meeting Houston (CDROM). Tarboton D. G., Bras, R. L., and Rodriguez-Iturbe, 1991, On the Extraction of Channel Networks from Digital Elevation Data, Hydrological Processes, v. 5, 81-100. http://viking.eps.pitt.edu

  10. Resultados do desenvolvimento de um propulsor à plasma no Brasil

    NASA Astrophysics Data System (ADS)

    Ferreira, I. S.; Ferreira, J. L.

    2003-08-01

    Uma das partes mais importantes de um satélite é o controle de atitude do mesmo. E se tratando de um satélite científico, a atenção para este sistema deve ser redobrada. Uma possibilidade atraente para executar esta tarefa é a propulsão elétrica. Aqui, mostraremos resultados obtidos pelo propulsor à plasma PHALL-01, desenvolvido na Universidade de Brasília entre 2000 e 2003. Este é derivado do propulsor russo SPT-100 (Stationary Plasma Thruster), mas com o emprego inovador de um arranjo de imãs permanentes como fonte do campo magnético, este último o agente da aceleração do plasma. Esta alteração foi motivada pelo objetivo de que o mesmo operasse com o mínimo de potência elétrica. A partir da formulação teórica do mecanismo de aceleração, tendo como base as equações da magnetohidrodinâmica, pode-se obter vínculos sob os quais o propulsor pudesse ser construído. O mais forte destes é o que dita a topologia do campo magnético. Sendo assim, foram realizadas simulações computacionais, que definiram a geometria do propulsor. Após construído, este foi diagnosticado usando-se sondas de Langmuir e analisadores de energia. Como resultados, obtivemos a distribuição espacial da temperatura, densidade e potencial do plasma, bem como a distribuição angular do feixe produzido pelo mesmo em vários regimes de operação. O espectro de energia do feixe de plasma também foi medido, indicando íons de até 560eV. Combinando estes resultados, calculou-se o empuxo do propulsor: 84mN; e o impulso específico: 1083s. Estes demonstram que o mesmo estará qualificado, num futuro próximo, para o emprego no controle de atitude de satélites científicos, ou até mesmo como parte do conjunto propulsor primário, responsáveis pela transferência de órbitas.

  11. Les garrots de prélèvement, un drame chez le nourrisson: à propos de 3 cas

    PubMed Central

    Ouangré, Edgar; Bazongo, Moussa; Ouédraogo, Isso; Zida, Maurice; Ouedraogo, Daouda; Sanou, Adama; Bonkoungou, Gilbert Patindé; Doamba, Rodrigue Namékinsba; Zongo, Nayi; Traore, Si Simon

    2016-01-01

    Le délai pour la levée d'un garrot sur un membre est limité, tout retard, surtout après la 3ème heure expose à un risque d'amputation de celui-ci. Notre objectif a été de rapporter trois cas de gangrène ischémique de membre par oubli d'un garrot après un prélèvement sanguin, afin d'interpeler le personnel soignant sur ses dangers. Il s'est agi de trois nourrissons dont deux de 3 mois et un de 5 mois, reçus aux urgences viscérales du CHU-Yalgado Ouédraogo pour tuméfaction du membre thoracique gauche. Dans leurs antécédents, on a noté une pose de garrot pour prélèvement de sang qui a été oublié pendant 24 heures dans deux cas et 48 heures dans un cas. L'examen avait retrouvé un œdème diffus associé à un sphacèle du membre supérieur remontant jusqu'au 1/3 moyen du bras; une abolition des pouls ulnaire et radial ainsi que de la sensibilité de la main dans 2 cas. Dans un cas les signes étaient atténués. Le diagnostic de gangrène ischémique de membre a été retenu dans tous les cas. La biologie réalisée était normale. En urgence, il a été réalisé une amputation trans-humérale dans 2 cas et un débridement associé à une amputation de quatre doigts dans un cas. L’évolution a été simple dans tous les cas. La gangrène sèche iatrogène de membre par garrot en milieu hospitalier ne devrait pas se concevoir. Cela passe par la rigueur dans l'administration des soins et une surveillance régulière et attentive des patients. PMID:27217892

  12. Chagas disease: current epidemiological trends after the interruption of vectorial and transfusional transmission in the Southern Cone countries.

    PubMed

    Moncayo, Alvaro

    2003-07-01

    Chagas disease, named after Carlos Chagas who first described it in 1909, exists only on the American Continent. It is caused by a parasite, Trypanosoma cruzi, transmitted to humans by blood-sucking triatomine bugs and by blood transfusion. Chagas disease has two successive phases, acute and chronic. The acute phase lasts 6 to 8 weeks. After several years of starting the chronic phase, 20% to 35% of the infected individuals, depending on the geographical area will develop irreversible lesions of the autonomous nervous system in the heart, esophagus, colon and the peripheral nervous system. Data on the prevalence and distribution of Chagas disease improved in quality during the 1980's as a result of the demographically representative cross-sectional studies carried out in countries where accurate information was not available. A group of experts met in Bras lia in 1979 and devised standard protocols to carry out countrywide prevalence studies on human T. cruzi infection and triatomine house infestation. Thanks to a coordinated multi-country program in the Southern Cone countries the transmission of Chagas disease by vectors and by blood transfusion has been interrupted in Uruguay in1997, in Chile in 1999, and in 8 of the 12 endemic states of Brazil in 2000 and so the incidence of new infections by T. cruzi in the whole continent has decreased by 70%. Similar control multi-country initiatives have been launched in the Andean countries and in Central America and rapid progress has been recorded to ensure the interruption of the transmission of Chagas disease by 2005 as requested by a Resolution of the World Health Assembly approved in 1998. The cost-benefit analysis of the investments of the vector control program in Brazil indicate that there are savings of US$17 in medical care and disabilities for each dollar spent on prevention, showing that the program is a health investment with good return. Since the inception in 1979 of the Steering Committee on Chagas Disease

  13. Lymphœdème unilatéral du membre supérieur au cours d'une polyarthrite rhumatoïde

    PubMed Central

    Bouomrani, Salem; Nouma, Hanène; Slama, Alaeddine; Chebbi, Safouane; Neffoussi, Marwa; Fara, Afef; Beji, Maher

    2015-01-01

    Les lymphœdèmes chroniques et localisés des membres ne sont qu'exceptionnellement signalés au cours de la polyarthrite rhumatoïde (PR). Nous rapportons l'observation d'une patiente âgée de 63 ans ayant une PR diagnostiquée depuis dix ans et traitée par hydroxychloroquine, prednisone et méthotrexate avec une bonne évolution fût explorée pour une tuméfaction du membre supérieur gauche évoluant depuis deux ans. À l'examen clinique on notait un membre infiltré en totalité, indolore, élastique et recouvert d'une peau tendue, luisante mais d'aspect normal. Le reste de l'examen somatique était sans particularités. La biologie ne montrait pas d'anomalies. L'imagerie médicale (radiographies-X standards des os de l'avant bras et du thorax, scanner-X thoracique, échographie des parties molles et du creux axillaire, doppler artériel et veineux du membre atteint et écho-mammographie) se révélait normale. La lympho-scintigraphie concluait à l'absence de visualisation du réseau lymphatique superficiel gauche. Le diagnostic de lymphœdème secondaire associé à la PR était retenu devant la négativité du bilan étiologique. Une kinésithérapie de drainage lymphatique fût prescrite en association à des assauts cortisoniques mais l'amélioration n’était que partielle. Parmi les manifestations extra articulaires de la PR, les lymphœdèmes chroniques localisés des membres restent inhabituels et souvent méconnus. Leurs mécanismes physiopathologiques sont mal élucidés et leur traitement ne fait pas encore l'unanimité. Ils gardent en revanche une implication pronostique fonctionnelle majeure. PMID:26448809

  14. Efeito do Solo do Materias Organicos E do Adubo Formula 4N:14P:8K Para Producao DA Batata (Solanum tuberosum L.) Semente Pre-Basica no Casa de Vegetacao

    NASA Astrophysics Data System (ADS)

    László, Márton

    2010-05-01

    Widely well know that the potato is an important vegetable crop at Brazíl. Plant grown on about 173.000 ha, with total yield of 2.6 million tons year-1. The average yield is about 15 t ha-1. This level is very low because degeneration of crop is rapid under high temperature and high viruses pressure. Therefore seed potato propagation and production is principal on consumption potato production. This is why we found it necessary to develop it. The latossolo vermelho soil-farmyard manure- burnt rice straw-fertilizer 4N:14P:8K greenhouse pot trial was set up at the National Vegetable Crops Research Center, Brasília-DF, Brazíl in 1990. The methods of the experiments were soil x farmyard manure x burnt rice straw, soil x 4N:14P:8K fertilizer and soil x farmyard manure x burnt rice straw x 4N:14P:8K fertilizer on randomized block design in total 29 combination of treatments in 5, 5 and 3 repetitions with in a total parcel of 116. According to chemical analysis of the a., soil, b., farmyard manure and c., burnt rice straw the agrochemistry parameters were as follows: a., latossolo vermelho soil: CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1, b., farmyard manure: N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., burnt rice straw: N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. The experimental datas were estimated by analysis of variance, ANOVA and MANOVA. The main conclusions were as follows: 1. Mixture of 80% latossolo vermelho, 10% burnt rice straw and 10% farmyard manure were shown best performance on seed potato productivity. The piece of tubers with a 0-20 mm (consumption seeds) was increased by 77%. 2. Total seed potato number was reached maximum at 10.8 g pot-1 4N:14P:8K fertilizer regarding to average of treatments with a 33%. 3. Dry biomassa production plant-1 was decreased by high dose of 4N:14P:8K fertilizer (18.0 g pot-1) with a

  15. EDITORIAL Proceedings of the XIV International Conference on Small-Angle Scattering, SAS-2009

    NASA Astrophysics Data System (ADS)

    Ungar, Goran; Heenan, Richard

    2010-10-01

    There are 52 papers in these Proceedings. The papers are divided into 10 thematic sections and a section for invited papers and reviews. The sections and the respective section editors are given below. Section Editor(s) Invited Papers and Reviews Peter Griffiths, Wim Bras, Rudolf Winter Beamlines and Instrumentation Elliot Gilbert, Wim Bras, Nigel Rhodes Theory, Data processing and Modelling Jan Skov Pedersen, Carlo Knupp Biological Systems and Membranes Richard Heenan, Cameron Neylon Ceramics, Glasses and Porous Materials Rudolf Winter Colloids and Solutions Peter Griffiths Hierarchical Structures and Fibres Steve Eichhorn, Karen Edler Metallic and Magnetic Systems Armin Hoell Polymers Patrick Fairclough Time resolved Diffraction, Kinetic and Dynamical Studies João Cabral, Christoph Rau We are grateful to all section editors and the many anonymous referees for their invaluable effort which made the publication of the Proceedings possible. The refereeing process was strict and thorough, some papers were rejected and most were improved. The resulting compendium gives a good overview of recent developments in small-angle X-ray and neutron scattering theory, application, methods of analysis and instrumentation. Thus it should be a useful source of reference for a number of years to come. The papers are a good reflection of the material presented at the meeting. Because of the general high quality of the articles, it was difficult to decide which to highlight and be fair to all contributors. The following in particular have caught the attention of the editors. Highlighted papers A statistical survey of publications reporting the application of SAXS and SANS by Aldo Craievich (paper 012003) is recommended reading for anyone needing convincing about the vibrancy of this scientific field and the ever expanding use of these techniques. Two aspects of coherent X-ray scattering, made available by the advent of the 3rd generation synchrotron sources, are discussed in the

  16. Extreme events of 2012, 2013 and 2014 linked to planetary wave resonance

    NASA Astrophysics Data System (ADS)

    Petoukhov, Vladimir; Coumou, Dim; Rahmstorf, Stefan; Stadtherr, Lisa; Kornhuber, Kai; Petri, Stefan; Schellnhuber, Hans Joachim

    2016-04-01

    Croatia. We have analysed this event in some detail and demonstrate a linkage to planetary wave resonance (Stadtherr et al., in revision). References Coumou D, Petoukhov V, Rahmstorf S, Petri S, and Schellnhuber HJ (2014) Quasi-resonant circulation regimes and hemispheric synchronization of extreme weather in boreal summer. Proc Natl Acad Sci USA 111: 12331-12336. Petoukhov V, Rahmstorf S, Petri S, Schellnhuber HJ (2013) Quasiresonant amplification of planetary waves and recent Northern Hemisphere weather extremes. Proc Natl Acad Sci USA 110(14): 5336-5341. Petoukhov V, Petri S, Rahmstorf S, Coumou D, Kornhuber K, Schellnhuber HJ (submitted) The role of quasi-resonant planetary wave dynamics in recent boreal spring-to-autumn extreme events. Proc Natl Acad Sci USA. Stadtherr L, Coumou D, Petoukhov V, Petri S, Rahmstorf S (in revision) Record Balkan floods of 2014 linked to planetary wave resonance. Science Advances.

  17. French antecedents of "contemporary" concepts in the American Psychiatric Association's classification of bipolar (mood) disorders.

    PubMed

    Haustgen, Thierry; Akiskal, Hagop

    2006-12-01

    Although first detailed descriptions of what we today term "bipolar disorders" are generally attributed to E. Kraepelin [Kraepelin, E., 1899 (1976 tr). Manic depressive insanity and paranoia. (reprint of English translation). Arno, New York], a review of French psychiatric literature from Esquirol to the middle of 20th century reveals major clinical contributions to the development of the concept of cyclic mood disorders, their phenomenology and classification as embodied in DSM-IV. The main treatise was published by the Paris psychiatric schools of Salpêtrière, Bicêtre, Charenton, Sainte-Anne and Vanves. Already much before Kraepelin, French authors had described most symptoms and the course of future DSM-IV bipolar, manic, major depressive [Falret, J.-P., 1854. De la folie circulaire ou forme de maladie mentale caracterisée par l'alternative régulière de la manie et de la mélancolie, Bull. Acad. Méd. XIX, 382-400.; Baillarger, J., 1854. Note sur un genre de folie dont les accès sont caractérisés par deux périodes régulières, l'une de dépression, l'autre d'excitation, Bull. Acad. Méd. XIX, 340 et Ann. Méd. Psychol. XII, 369], hypomanic and mixed episodes [Falret, J., 1861. Principes à suivre dans la classification des maladies mentales, Ann. Méd. Psychol. XIX, 145.; Falret, J., 1866, 1867. La folie raisonnante ou folie morale, Ann. Méd. Psychol. XXIV, 382, XXV, 68], as well as - under other names - the characteristics of bipolar II disorder, various specifiers describing mood episode and course of recurrent episodes [Ritti, A., 1883. Traité clinique de la folie à double forme (folie, circulaire, délire à formes alternes). Doin, Paris]. The synthesis of these clinical observations led to Magnan's "intermittent madness" (1893), a precursor of Kraepelin's "manic-depressive psychosis". After 1899, French authors generally adhered to their classification of autonomous depressive disorder (melancholia), as distinct from manic-depressive insanity

  18. Facteurs prédictifs de succès des étudiants en première année de médecine à l'université de Parakou

    PubMed Central

    Adoukonou, Thierry; Tognon-Tchegnonsi, Francis; Mensah, Emile; Allodé, Alexandre; Adovoekpe, Jean-Marie; Gandaho, Prosper; Akpona, Simon

    2016-01-01

    Introduction Plusieurs facteurs dont les notes obtenues au BAC peuvent influencer les performances académiques des étudiants en première année de médecine. L'objectif de cette étude était d’évaluer la relation entre les résultats des étudiants au BAC et le succès en première année de médecine. Méthodes Nous avons réalisé une étude analytique ayant inclus l'ensemble des étudiants régulièrement inscrits en première année à la Faculté de Médecine de l'université de Parakou durant l'année académique 2010-2011. Les données concernant les notes par discipline et mention obtenue au BAC ont été collectées. Une analyse multivariée utilisant la régression logistique et la régression linéaire multiple a permis d’établir les meilleurs prédicteurs du succès et de la moyenne de l’étudiant en fin d'année. Le logiciel SPSS version 17.0 a été utilisé pour l'analyse des données et un p<0,05 a été considéré comme statistiquement significatif. Résultats Parmi les 414 étudiants régulièrement inscrits les données de 407 ont pu être exploitées. Ils étaient âgés de 15 à 31 ans; 262 (64,4%) étaient de sexe masculin. 98 étaient admis avec un taux de succès de 23,7%. Le sexe masculin, la note obtenue en mathématiques, en sciences physiques, la moyenne au BAC et la mention étaient associés au succès en fin d'année mais en analyse multivariée seule une note en sciences physiques > 15/20 était associée au succès (OR: 2,8 [1,32- 6,00]). Pour la moyenne générale obtenue en fin d'année seule une mention bien obtenue au BAC était associée (coefficient de l'erreur standard: 0,130 Bêta =0,370 et p=0,00001). Conclusion Les meilleurs prédicateurs du succès en première année étaient une bonne moyenne en sciences physiques au BAC et une mention bien. La prise en compte de ces éléments dans le recrutement des étudiants en première année pourrait améliorer les résultats académiques. PMID:27313819

  19. The Missing Memory of Canadian Sociology: Reflexive Government and "the Social Science".

    PubMed

    Curtis, Bruce

    2016-05-01

    The modest literature on the history of Canadian Sociology takes the appearance of a named academic discipline as its object. Canadian Sociology is held to have had some precursors in the 1880s, but really to appear only in the 1920s. It is described as a foreign import and as an activity first of intellectual speculation and moral reform. Observational and analytic practice are absent before 1880. The activities of state agents and government departments in the social field are not discussed. This article offers a richer account through an examination of the larger field from which Sociology was extracted, "the social science," which was practiced actively in colonial Canada from the early nineteenth century. The social science shaped and was itself shaped by colonial conditions. The article outlines three interrelated moments in social science to carry its claims: inventory-making, the emergence of "population-thinking," and "reflexive government." Attending to the social science underlines the complex and convoluted relations of sociology with state power. Les rares oeuvrages académiques portant sur l'histoire de la sociologie canadienne prend pour objet l'apparition du terme dans le contexte universitaire. Dans cet optique, ils signalent certains précurseurs de la sociologie canadienne dès les années 1880, mais en fait ils affirment que cette discipline n'apparaît que dans les années 1920. Cette discipline est présentée comme une importation académique et, d'abord et avant tout, comme de la spéculation intellectuelle et comme un projet de réforme morale. D'après cette vision, les pratiques d'observation et d'analyse sociales ne semblent pas exister avant 1880, et les acteurs politiques et administratifs sont absents du terrain. Notre article propose un examen plus riche du vaste champ duquel la sociologie académique fut arrachée: activement pratiquée au Canada à l'époque coloniale dès le début du XIXe si

  20. The Missing Memory of Canadian Sociology: Reflexive Government and "the Social Science".

    PubMed

    Curtis, Bruce

    2016-05-01

    The modest literature on the history of Canadian Sociology takes the appearance of a named academic discipline as its object. Canadian Sociology is held to have had some precursors in the 1880s, but really to appear only in the 1920s. It is described as a foreign import and as an activity first of intellectual speculation and moral reform. Observational and analytic practice are absent before 1880. The activities of state agents and government departments in the social field are not discussed. This article offers a richer account through an examination of the larger field from which Sociology was extracted, "the social science," which was practiced actively in colonial Canada from the early nineteenth century. The social science shaped and was itself shaped by colonial conditions. The article outlines three interrelated moments in social science to carry its claims: inventory-making, the emergence of "population-thinking," and "reflexive government." Attending to the social science underlines the complex and convoluted relations of sociology with state power. Les rares oeuvrages académiques portant sur l'histoire de la sociologie canadienne prend pour objet l'apparition du terme dans le contexte universitaire. Dans cet optique, ils signalent certains précurseurs de la sociologie canadienne dès les années 1880, mais en fait ils affirment que cette discipline n'apparaît que dans les années 1920. Cette discipline est présentée comme une importation académique et, d'abord et avant tout, comme de la spéculation intellectuelle et comme un projet de réforme morale. D'après cette vision, les pratiques d'observation et d'analyse sociales ne semblent pas exister avant 1880, et les acteurs politiques et administratifs sont absents du terrain. Notre article propose un examen plus riche du vaste champ duquel la sociologie académique fut arrachée: activement pratiquée au Canada à l'époque coloniale dès le début du XIXe si

  1. Farmyard Manure and Fertilizer Effects on Seed Potato (Solanum tuberosum L.) Yield in Green House Production

    NASA Astrophysics Data System (ADS)

    László, M.

    2009-04-01

    Nowadays is widely well know that the potato is an important vegetable crop at Brazíl. It is grown on about 173.000 ha, with total yield of 2.6 million tons year-1. The average yield is 15 t ha-1. This level is very low because degeneration of crop is rapid under high temperature and high viruses pressure. Therefore seed potato propagation and production is principal on consumption potato production. This is why we found it necessary to develop it. The latossolo vermelho soil-farmyard manure- burnt rice straw-fertilizer 4N:14P:8K greenhouse pot trial was set up at the National Vegetable Crops Research Center, Brasília-DF, Brazíl in 1990. The methods of the experiments were soil x farmyard manure x burnt rice straw, soil x 4N:14P:8K fertilizer and soil x farmyard manure x burnt rice straw x 4N:14P:8K fertilizer on randomized block design in total 29 combination of treatments in 5, 5 and 3 repetitions with in a total parcel of 116. According to chemical analysis of the a., soil, b., farmyard manure and c., burnt rice straw the agrochemistry parameters were as follows (estimated datas): a., latossolo vermelho soil: CaCO3 0.3-0.7%, humo 0.9-1.0%, pH (H2O) 5.3, pH (KCl) 4.5, AL- P2O5 3.2-3.5 mg kg-1, AL- K2O 180 mg kg-1, Mg (KCl) 70 mg kg-1, EDTA-Zn 0.5-0.8 mg kg-1, EDTA-Cu 0.5-0.6 mg kg-1, b., farmyard manure: N 1.8 g kg-1, P2O5 2.0 g kg-1, K2O 4.0 g kg-1, c., burnt rice straw: N 0.8 g kg-1, P2O5 7.0 g kg-1, K2O 4.5 g kg-1. The experimental datas were estimated by analysis of variance, ANOVA and MANOVA. The main conclusions were as follows: 1. Mixture of 80% latossolo vermelho, 10% burnt rice straw and 10% farmyard manure were shown best performance on seed potato productivity. The piece of tubers with a 0-20 mm (consumption seeds) was increased by 77%. 2. Total seed potato number was reached maximum at 10.8 g pot-1 4N:14P:8K fertilizer regarding to average of treatments with a 33%. 3. Dry biomassa production plant-1 was decreased by high dose of 4N:14P:8K

  2. [Effect of precipitation and seasonal period on the patterns of commuting to school in children and adolescents from Granada].

    PubMed

    Segura-Díaz, José Manuel; Herrador-Colmenero, Manuel; Martínez-Téllez, Borja; Chillón Garzón, Palma

    2014-12-17

    Introducción: El desplazamiento activo (ir andando o en bicicleta) al centro educativo contribuye a aumentar los niveles de actividad física en jóvenes. Las condiciones climatológicas podrían influenciar dicho comportamiento. Objetivo: El objetivo es estudiar la influencia de la precipitación en forma de lluvia y del periodo estacional, en el modo de desplazamiento al colegio e instituto en niños y adolescentes de la ciudad de Granada. Método: Participaron un total de 384 estudiantes (166 niños y 218 adolescentes) entre 8 y 18 años de 2 centros (colegio e instituto) de la capital Granadina. Los participantes completaron un cuestionario sobre el modo de desplazamiento semanal en las tres estaciones del año académico. Los datos de precipitación en estas tres semanas fueron obtenidos desde la Agencia Estatal de Meteorología. Las asociaciones entre la precipitación en forma de lluvia y la estación con el modo de desplazamiento activo al colegio se estudió mediante el test McNemar. Resultados: A nivel general, no se encontraron asociaciones significativas entre la precipitación y el periodo estacional con el modo de desplazamiento de los niños y adolescentes (p>0,05) a excepción de dos asociaciones: a) el efecto positivo de la lluvia en el porcentaje de niños que andan al colegio entre un día lluvioso y un día no lluvioso en primavera (p=0,031) y b) el ligero efecto de la estación en el porcentaje de niños y adolescentes que andan entre otoño e invierno (45,8% y 37,5% andan) y entre otoño y primavera (59,7% y 56%) respectivamente (p=0,07). Conclusión: Las condiciones climatológicas parecen tener poca influencia en el modo de desplazamiento en niños y adolescentes de Granada, pareciendo existir un hábito constante en dicho comportamiento a lo largo del curso académico.

  3. Renewal-reward process formulation of motor protein dynamics.

    PubMed

    Krishnan, Arjun; Epureanu, Bogdan I

    2011-10-01

    Renewal-reward processes are used to provide a framework for the mathematical description of single-molecule bead-motor assays for processive motor proteins. The formulation provides a more powerful, general approach to the fluctuation analysis of bead-motor assays begun by Svoboda et al. (Proc. Natl. Acad. Sci. USA 91(25):11782, 1994). Fluctuation analysis allows one to gain insight into the mechanochemical cycle of motor proteins purely by measuring the statistics of the displacement of the cargo (e.g., bead) the protein transports. The statistical parameters of interest are shown to be the steady-state slopes (in time) of the cumulants of the bead (the cumulant rates). The first two cumulant rates are the steady-state velocity and slope of the variance. The cumulant rates are shown to be insensitive to experimental disturbances such as the initial state of the enzyme and from the viewpoint of modeling, unaffected by substeps. Two existing models--Elston (J. Math. Biol. 41(3):189-206, 2000) and Peskin and Oster (Biophys. J. 68(4):202S-211S, 1995)--are formulated as renewal-reward processes to demonstrate the insight that the formulation affords. A key contribution of the approach is the possibility of accounting for wasted hydrolyses and backward steps in the fluctuation analysis. For example, the randomness parameter defined in the first fluctuation analysis of optical trap based bead-motor assays (Svoboda et al. in Proc. Natl. Acad. Sci. USA 91(25):11782, 1994), loses its original purpose of estimating the number of rate-determining steps in the chemical cycle when backward steps and wasted hydrolyses are present. As a simple application of our formulation, we extend the randomness parameter's scope by showing how it can be used to infer the presence of wasted hydrolyses and backward steps with certainty. A more powerful fluctuation analysis using higher cumulant rate measurements is proposed: the method allows one to estimates the number of intermediate

  4. Free energy and information contents of conformons in proteins and DNA.

    PubMed

    Ji, S

    2000-01-01

    Sequence-specific conformational strains (SSCS) of biopolymers that carry free energy and genetic information have been called conformons, a term coined independently by two groups over two and a half decades ago [Green, D.E., Ji, S., 1972. The electromechanochemical model of mitochondrial structure and function. In: Schultz, J., Cameron, B.F. (Eds.), Molecular Basis of Electron Transport. Academic Press, New York, pp. 1-44; Volkenstein, M.V., 1972. The Conformon. J. Theor. Biol. 34, 193-195]. Conformons provide the molecular mechanisms necessary and sufficient to account for all biological processes in the living cell on the molecular level in principle--including the origin of life, enzymic catalysis, control of gene expression, oxidative phosphorylation, active transport, and muscle contraction. A clear example of SSCS is provided by SIDD (strain-induced duplex destabilization) in DNA recently reported by Benham [Benham, C.J., 1996a. Duplex destabilization in superhelical DNA is predicted to occur at specific transcriptional regulatory regions. J. Mol. Biol. 255, 425-434; Benham, C.J., 1996b. Computation of DNA structural variability--a new predictor of DNA regulatory regions. CABIOS 12(5), 375-381]. Experimental as well as theoretical evidence indicates that conformons in proteins carry 8-16 kcal/mol of free energy and 40-200 bits of information, while those in DNA contain 500-2500 kcal/mol of free energy and 200-600 bits of information. The similarities and differences between conformons and solitons have been analyzed on the basis of the generalized Franck-Condon principle [Ji, S., 1974a. A general theory of ATP synthesis and utilization. Ann. N.Y. Acad. Sci. 227, 211-226; Ji, S., 1974b. Energy and negentropy in enzymic catalysis. Ann. N.Y. Acad. Sci. 227, 419-437]. To illustrate a practical application, the conformon theory was applied to the molecular-clamp model of DNA gyrase proposed by Berger and Wang [Berger, J.M., Wang, J.C., 1996. Recent developments

  5. Discussions about the Nature of Science in a Course on the History of Astronomy. (Spanish Title: Discusiones sobre la Naturaleza de la Ciencia en un Curso sobre Historia de la Astronomía.) Discussões sobre a Natureza da Ciência em um Curso sobre a História da Astronomia

    NASA Astrophysics Data System (ADS)

    Pires de Andrade, Victória Flório; L'Astorina, Bruno

    2010-07-01

    There are an increasing number of researches in science education that affirm the importance of discussions on the "nature of science" in basic education level as well as in teacher training. The history of science applied to education is a way to contextualize epistemological discussions, allowing both the understanding of scientific content and learning about science concepts. We present some reasonably consensual definitions on the nature of science that have been widely discussed by the academic community. We show also some episodes in the history of astronomy which can lead to discussions involving some aspects of the nature of science, and how they can do it. Hay un número creciente de investigaciones en la enseñanza de las ciencias que afirman la importancia de debates sobre la "naturaleza de la ciencia" en la educación básica y formación del profesorado. La historia de la ciencia aplicada a la educación es una manera de contextualizar los debates de la epistemología, lo que permite tanto la comprensión de los contenidos científicos como el aprendizaje de conceptos científicos. En esto trabajo, presentamos algunas definiciones bastante consensuales sobre la naturaleza de la ciencia que han sido ampliamente discutidas por la comunidad académica y mostramos cómo algunos episodios en la historia de la astronomía pueden llevar a discusiones sobre algunos aspectos de la naturaleza de la ciencia. Há um número crescente de pesquisas na área de ensino de ciências que afirmam a importância de discussões sobre a "natureza da ciência" na educação básica e na formação de professores. A história da ciência aplicada ao ensino é uma maneira de contextualizar discussões epistemológicas, permitindo tanto a compreensão de conteúdos científicos quanto o aprendizado de noções sobre as ciências. Neste trabalho apresentamos algumas definições razoavelmente consensuais sobre a natureza da ciência que foram amplamente discutidas pela

  6. The role of genomics in conservation and reproductive sciences.

    PubMed

    Johnson, Warren E; Koepfli, Klaus

    2014-01-01

    maintaining functional ecosystems, evolutionary process and will impact future food supplies, human health, biomaterial development and geopolitics (Myers and Knoll Proc Natl Acad Sci U S A 98:5389-5392, 2001; Templeton et al. Proc Natl Acad Sci U S A 98:5426-5432, 2001). Therefore, conservation of genetic diversity is a social, cultural, scientific, and economic prerogative and is the key to adaptation in the uncertain future of a human-dominated environment. Once lost, genetic resources are nearly impossible to regain, increasing the urgency of fundamental global approaches (e.g. www.cbd.int/sp/targets ).In this chapter we provide a review of current research and recent advances in biotechnology and genomic approaches for animal conservation and the management of genetic resources, with an emphasis on reproductive sciences. It is intended to provide information and insights for research and to provoke thoughts on how to take advantage of these opportunities. PMID:25091907

  7. Quaternary structure of carbonmonoxyhemoglobins in solution: structural changes induced by the allosteric effector inositol hexaphosphate.

    PubMed

    Gong, Qingguo; Simplaceanu, Virgil; Lukin, Jonathan A; Giovannelli, Janel L; Ho, Nancy T; Ho, Chien

    2006-04-25

    We have applied the residual dipolar coupling (RDC) method to investigate the solution quaternary structures of (2)H- and (15)N-labeled human normal adult recombinant hemoglobin (rHb A) and a low-oxygen-affinity mutant recombinant hemoglobin, rHb(alpha96Val-->Trp), both in the carbonmonoxy form, in the absence and presence of an allosteric effector, inositol hexaphosphate (IHP), using a stretched polyacrylamide gel as the alignment medium. Our recent RDC results [Lukin, J. A., Kontaxis, G., Simplaceanu, V., Yuan, Y., Bax, A., and Ho, C. (2003) Proc. Natl. Acad. Sci. U.S.A. 100, 517-520] indicate that the quaternary structure of HbCO A in solution is a dynamic ensemble between two previously determined crystal structures, R (crystals grown under high-salt conditions) and R2 (crystals grown under low-salt conditions). On the basis of a comparison of the geometric coordinates of the T, R, and R2 structures, it has been suggested that the oxygenation of Hb A follows the transition pathway from T to R and then to R2, with R being the intermediate structure [Srinivasan, R., and Rose, G. D. (1994) Proc. Natl. Acad. Sci. U.S.A. 91, 11113-11117]. The results presented here suggest that IHP can shift the solution quaternary structure of HbCO A slightly toward the R structure. The solution quaternary structure of rHbCO(alpha96Val-->Trp) in the absence of IHP is similar to that of HbCO A in the presence of IHP, consistent with rHbCO(alpha96Val-->Trp) having an affinity for oxygen lower than that of Hb A. Moreover, IHP has a much stronger effect in shifting the solution quaternary structure of rHbCO(alpha96Val-->Trp) toward the R structure and toward the T structure, consistent with IHP causing a more pronounced decrease in its oxygen affinity. The results presented in this work, as well as other results recently reported in the literature, clearly indicate that there are multiple quaternary structures for the ligated form of hemoglobin. These results also provide new insights

  8. Temporal Correlations In Natural Time Analysis and Tsallis Non Extensive Statistical Mechanics

    NASA Astrophysics Data System (ADS)

    Sarlis, N. V.; Varotsos, P.; Skordas, E. S.

    2015-12-01

    Upon analyzing the seismic catalog in a new time domain termed natural time[1-3] and employing a sliding natural time window comprising a number of events that would occur in a few months, we find that the fluctuations β of the order parameter of seismicity[4] show a minimum βmin a few months before major earthquakes (EQs)[5,6]. Such a minimum appears simultaneously[7] with the initiation of Seismic Electric Signals activity[8] being the first time in which two geophysical observables of different nature exhibit simultaneous anomalous behavior before major EQs. In addition, we show[9] that each precursory βmin is preceded as well as followed by characteristic changes of temporal correlations between EQ magnitudes identified by the celebrated Detrended Fluctuation Analysis of magnitude time series. We indicate that Tsallis non extensive statistical mechanics[10], in the frame of which kappa distributions arise[11], can capture temporal correlations between EQ magnitudes if complemented with natural time analysis [12]. References P.A. Varotsos, N.V. Sarlis, and E.S. Skordas, Phys Rev E, 66 (2002) 011902. P.A. Varotsos et al., Phys Rev E 72 (2005) 041103. Varotsos P. A., Sarlis N. V. and Skordas E. S., Natural Time Analysis: The new view of time. (Springer-Verlag, Berlin Heidelberg) 2011. N. V. Sarlis, E. S. Skordas and P. A. Varotsos, EPL 91 (2010) 59001. N. V. Sarlis et al., Proc Natl Acad Sci USA 110 (2013) 13734. N. V. Sarlis et al., Proc Natl Acad Sci USA 112 (2015) 986. P. A. Varotsos et al., Tectonophysics, 589 (2013) 116. P. Varotsos and M. Lazaridou, Tectonophysics 188 (1991) 321. P. A. Varotsos, N. V. Sarlis, and E. S. Skordas, J Geophys Res Space Physics, 119 (2014), 9192, doi: 10.1002/2014JA0205800. C. Tsallis, J Stat Phys 52 (1988) 479. G. Livadiotis, and D. J. McComas, J Geophys Res 114 (2009) A11105, doi:10.1029/2009JA014352. N. V. Sarlis, E. S. Skordas and P. A. Varotsos, Phys Rev E 82 (2010) 021110.

  9. [Salivary cortisol as a measure of stress during a nutrition education program in adolescents].

    PubMed

    Pérez-Lancho, C; Ruiz-Prieto, I; Bolaños-Ríos, P; Jáuregui-Lobera, I

    2013-01-01

    Objetivos: Analizar el nivel de estrés, en distintos momentos académicos, mediante la determinación de cortisol salivar y evaluar la influencia de dicho nivel de estrés en la eficacia de un programa de educación nutricional en adolescentes. Métodos: Se determinó el cortisol salival (mañana y noche) de 42 estudiantes de educación secundaria obligatoria, al inicio de curso y en el momento previo a los exámenes finales. Se desarrolló durante el curso un programa de educación nutricional y se recogieron datos de consumo de alimentos mediante un cuestionario de frecuencia en ambos momentos inicial y final. Igualmente, se determinó el índice de masa corporal. Resultados: El cortisol de mañana inicial fue menor que el de mañana final (P < 0,05), con niveles más elevados en las chicas (P < 0,05). En la determinación final, el cortisol de mañana también resultó más elevado en las chicas (P < 0,01). No hubo variaciones significativas en el índice de masa corporal. El 23.8% de los estudiantes refirió ingerir menos bebidas carbonatadas tras la intervención, mientras que el 28,57% destacó el hecho de haber incluido el desayuno antes de salir de casa. Se observó una reducción del consumo de frutas al final del estudio. Discusión: Para valorar adecuadamente si los cambios están relacionados con el programa de educación nutricional o con la situación estresante debida a la proximidad de los exámenes, que implicaría un aumento en la ingesta, serían necesarios más estudios a realizar en diferentes etapas del curso académico.

  10. Genetic analysis of the DNA recognition sequence of the P2 Cox protein.

    PubMed Central

    Cores de Vries, G; Wu, X S; Haggård-Ljungquist, E

    1991-01-01

    The Cox protein of temperate Escherichia coli phage P2 is involved in three important biological processes: (i) excision of the integrated prophage genome (G. Lindahl and M. Sunshine, Virology 49:180-187, 1972), (ii) transcriptional repression of the P2 Pc promoter, which controls the expression of the immunity repressor C and the integrase (S. Saha, E. Haggård-Ljungquist, and K. Nordström, EMBO J. 6:3191-3199, 1987), and (iii) transcriptional activation of the late PII promoter of the unrelated satellite phage P4 (S. Saha, E. Haggård-Ljungquist, and K. Nordström, Proc. Natl. Acad. Sci. USA 86:3973-3977, 1989). A comparison of the DNA regions protected by Cox from DNaseI degradation has revealed a presumptive Cox recognition sequence (Saha et al., Proc. Natl. Acad. Sci. USA). The binding region of Cox in the P2 Pc promoter contains three presumptive recognition sequences, "Cox boxes," located in tandem. P2 vir3 and P2 vir24 are virulent deletion mutants unable to plate on Cox-producing strains, most likely because the deletions locate the new early promoters too close to the Cox-binding region (Saha et al., EMBO J.). In this report, spontaneous P2 vir3 and vir24 mutants, no longer sensitive to repression by the Cox protein, have been isolated. These mutants plate with equal efficiency on strains with or without a Cox-producing plasmid, and they have been named cor for cox resistance. Three types are recognized; the four P2 vir3 cor mutants have a 1-base deletion in the first Cox box, while the P2 vir24 cor mutants were of two types; four have a base substitution in the first Cox box, and one has a base substitution in the second Cox box. The effect of the Cox protein on the mutated P2 vir3 and vir24 promoters was analyzed in vivo by using fusions to a promoterless cat (chloramphenicol acetyltransferase) gene. The activities of the P2 vir3 and vir24 early promoters, as opposed to the wild-type early Pe promoter, are drastically reduced by the Cox protein, and

  11. Academic Dishonesty among Physical Therapy Students: A Descriptive Study.

    PubMed

    Montuno, Eli; Davidson, Alex; Iwasaki, Karen; Jones, Susan; Martin, Jay; Brooks, Dina; Gibson, Barbara E; Mori, Brenda

    2012-01-01

    Objectif : Étudier les comportements malhonnêtes sur le plan académique à partir des pratiques actuelles des étudiants en physiothérapie (PT) et des comportements antérieurs des formateurs alors qu'ils étaient eux-mêmes étudiants en PT. Méthode : Un questionnaire sur le Web a été envoyé à 174 étudiants et à 250 formateurs dans des programmes de PT de l'Université de Toronto. Ce questionnaire a permis de recueillir des données démographiques ainsi que des données sur la prévalence, le degré de gravité et les facteurs contribuant à la malhonnêteté académique (MA). Résultats : Au total, 52 % des formateurs et 44,3 % des étudiants ont répondu au questionnaire durant la période de collecte des données, qui a duré six semaines. Les comportements considérés comme les plus graves ont été ceux que les formateurs et les étudiants ont le moins adoptés. L'influence de la génération à laquelle appartenaient les participants sur les attitudes par rapport à la MA et sur sa prévalence a été minime. Les facteurs contribuant à la MA le plus fréquemment évoqués sont les pressions liées aux études, un désaccord avec les méthodes d'évaluation et la perception que « tout le monde le fait ». Conclusion : Cette étude a permis de comparer les conclusions d'une étude similaire menée dans d'autres programmes de formation du secteur de la santé; il y a effectivement des cas de MA dans l'enseignement de la PT. Celle-ci est toutefois plus fréquente quand c'est pour aider des confrères ou consœurs que dans le seul intérêt personnel. La similitude des comportements des diverses générations de participants semble indiquer que certaines formes de tricherie sont acceptées parmi les normes sociales et peuvent être fonction de l'environnement.

  12. Coupled Modeling of Fault Poromechanics During Geologic CO2 Storage

    NASA Astrophysics Data System (ADS)

    Jha, B.; Hager, B. H.; Juanes, R.

    2012-12-01

    through faults in realistic CO2 injection scenarios. B. Aagaard et al., "Pylith User Manual version 1.6.1, Computational Infrastructure for Geodynamics," (2011). J. T. Birkholzer and Q. Zhou, Int. J. Greenh. Gas Control 3:745-756 (2009). F. Cappa, and J. Rutqvist, Geophys. Res. Lett. 38, L17313 (2011). O. Coussy, "Mechanics of Porous Continua", John Wiley & Sons, (1995) J. Kim, H. A. Tchelepi, and R. Juanes, Soc. Pet. Eng. J. 16, 249 (2011). M. L. Szulczewski et al., Proc. Natl. Acad. Sci. USA 109:5185-5189 (2012). M. D. Zoback and S. M. Gorelick, Proc. Natl. Acad. Sci. USA, 109: 10164-10168 (2012). Displacement field in a synthetic reservoir with a CO2 injection well, a brine relieve well, and a fault. Notice the slip on the fault.

  13. The Noble Gas Fingerprint in a UK Unconventional Gas Reservoir

    NASA Astrophysics Data System (ADS)

    McKavney, Rory; Gilfillan, Stuart; Györe, Domokos; Stuart, Fin

    2016-04-01

    helium and neon isotopic signatures exhibit a small but resolvable mantle input previously unseen onshore in the United Kingdom. We will outline the potential sources of this mantle input. 1. Osborn et al. (2011). Proc. Natl. Acad. Sci. U. S. A. 108, 10.1073/pnas.1100682108 2. Baldassare et al. (2014). Am. Assoc. Pet. Geol. Bull. 98, 10.1306/06111312178 3 .Ballentine et al. (2002). Rev. Min. Geochem. 47, 10.2138/rmg.2002.47.13 4. Gilfillan & Wilkinson (2011). Int. J. 5, 10.1016/j.ijggc.2011.08.008 5. Darrah et al. (2014). Proc. Natl. Acad. Sci. 111, 10.1073/pnas.1322107111

  14. On the Chemical Emergence of Phosphate-Based Biochemistry

    NASA Astrophysics Data System (ADS)

    Kee, Terence

    Contemporary organisms use orthophosphate derivatives (PO43-) in their cell biochemistry,1 yet questions remain as to how Nature was able to accumulate, activate and exploit the or-thophosphate group from geological sources with both poorly solubility and low chemical activ-ity.2 Gulick argued3 a central role for reduced oxidation state phosphorus (P) oxyacids such as H-phosphonates (H2PO3-) and especially H-phosphinates (H2PO2-) in prebiotic chemistry on account of the greater water solubility of their metal salts and, with the presence of P-H bonds, a different reactivity profile to that expected of orthophosphate. The recent demonstration that hydrothermal corrosion of P-rich mineral phases such as schreibersite (Fe,Ni)3P within iron meteorites leads to production of various P-oxyacids including H-phosphonic (H3PO3)4 and H-phosphinic5 acids as well as orthophosphate has reignited interest in reduced oxida-tion state P chemistry in prebiotic environments. We are examining the prebiotic potential of reduced oxidation state P-chemistry through reactions with carbonyl substrates with rea-sonable prebiotic provenance including formaldehyde glycolaldehyde, both intimately involved in the formose reaction for sugar synthesis6 and pyruvic acid,7 a product of glycolysis and feed-stock for the citric acid cycle, a fundamental cellular metablic process whose heritage is considered an ancient one. In this contribution we present some of our latest results on the H-phosphinate-pyruvate system. References: [1] Lodish H et al. (2000) Molecular Cell Biology, 4th Ed., W. H. Freeman Co., New York. [2] Gulick A. (1955) Am. Sci., 43, 479. [3] Gulick A. (1957) Ann. N. Y. Acad. Sci. 69, 309. [4] Pasek M. A. (2008) Proc. Nat. Acad. Sci. USA, 105, 853. [5] Bryant D. E.and Kee T. P. (2006) Chem. Commun. 2344. [6] Weber A. L. (2000) Origins of Life and Evol. Biosph., 30, 33. [7] Cody G. D. et. al. (2000) Science 289, 1337.

  15. The role of genomics in conservation and reproductive sciences.

    PubMed

    Johnson, Warren E; Koepfli, Klaus

    2014-01-01

    maintaining functional ecosystems, evolutionary process and will impact future food supplies, human health, biomaterial development and geopolitics (Myers and Knoll Proc Natl Acad Sci U S A 98:5389-5392, 2001; Templeton et al. Proc Natl Acad Sci U S A 98:5426-5432, 2001). Therefore, conservation of genetic diversity is a social, cultural, scientific, and economic prerogative and is the key to adaptation in the uncertain future of a human-dominated environment. Once lost, genetic resources are nearly impossible to regain, increasing the urgency of fundamental global approaches (e.g. www.cbd.int/sp/targets ).In this chapter we provide a review of current research and recent advances in biotechnology and genomic approaches for animal conservation and the management of genetic resources, with an emphasis on reproductive sciences. It is intended to provide information and insights for research and to provoke thoughts on how to take advantage of these opportunities.

  16. Modeling of optical spectra of the light-harvesting CP29 antenna complex of photosystem II--part II.

    PubMed

    Feng, Ximao; Kell, Adam; Pieper, Jörg; Jankowiak, Ryszard

    2013-06-01

    Until recently, it was believed that the CP29 protein from higher plant photosystem II (PSII) contains 8 chlorophylls (Chl's) per complex (Ahn et al. Science 2008, 320, 794-797; Bassi et al. Proc. Natl. Acad. Sci. U.S.A. 1999, 96, 10056-10061) in contrast to the 13 Chl's revealed by the recent X-ray structure (Pan et al. Nat. Struct. Mol. Biol. 2011, 18, 309-315). This disagreement presents a constraint on the interpretation of the underlying electronic structure of this complex. To shed more light on the interpretation of various experimental optical spectra discussed in the accompanying paper (part I, DOI 10.1021/jp4004328 ), we report here calculated low-temperature (5 K) absorption, fluorescence, hole-burned (HB), and 300 K circular dichroism (CD) spectra for CP29 complexes with a different number of pigments. We focus on excitonic structure and the nature of the low-energy state using modeling based on the X-ray structure of CP29 and Redfield theory. We show that the lowest energy state is mostly contributed to by a612, a611, and a615 Chl's. We suggest that in the previously studied CP29 complexes from spinach (Pieper et al. Photochem. Photobiol.2000, 71, 574-589) two Chl's could have been lost during the preparation/purification procedure, but it is unlikely that the spinach CP29 protein contains only eight Chl's, as suggested by the sequence homology-based study (Bassi et al. Proc. Natl. Acad. Sci. U.S.A.1999, 96, 10056-10061). The likely Chl's missing in wild-type (WT) CP29 complexes studied previously (Pieper et al. Photochem. Photobiol. 2000, 71, 574-589) include a615 and b607. This is why the nonresonant HB spectra shown in that reference were ~1 nm blue-shifted with the low-energy state mostly localized on about one Chl a (i.e., a612) molecule. Pigment composition of CP29 is discussed in the context of light-harvesting and excitation energy transfer.

  17. Adsorption mechanism of myelin basic protein on model substrates and its bridging interaction between the two surfaces.

    PubMed

    Lee, Dong Woog; Banquy, Xavier; Kristiansen, Kai; Min, Younjin; Ramachandran, Arun; Boggs, Joan M; Israelachvili, Jacob N

    2015-03-17

    Myelin basic protein (MBP) is an intrinsically disordered (unstructured) protein known to play an important role in the stability of myelin's multilamellar membrane structure in the central nervous system. The adsorption of MBP and its capacity to interact with and bridge solid substrates has been studied using a surface forces apparatus (SFA) and a quartz crystal microbalance with dissipation (QCM-D). Adsorption experiments show that MBP molecules adsorb to the surfaces in a swollen state before undergoing a conformational change into a more compact structure with a thickness of ∼3 nm. Moreover, this compact structure is able to interact with nearby mica surfaces to form adhesive bridges. The measured adhesion force (energy) between two bridged surfaces is 1.0 ± 0.1 mN/m, (Ead = 0.21 ± 0.02 mJ/m(2)), which is slightly smaller than our previously reported adhesion force of 1.7 mN/m (Ead = 0.36 mJ/m(2)) for MBP adsorbed on two supported lipid bilayers (Lee et al., Proc. Natl. Acad. Sci. U.S.A. 2014, 111, E768-E775). The saturated surface concentration of compact MBP on a single SiO2 surface reaches a stable value of 310 ± 10 ng/cm(2) regardless of the bulk MBP concentration. A kinetic three-step adsorption model was developed that accurately fits the adsorption data. The developed model is a general model, not limited to intrinsically disordered proteins, that can be extended to the adsorption of various chemical compounds that undergo chemical reactions and/or conformational changes upon adsorbing to surfaces. Taken together with our previously published data (Lee et al., Proc. Natl. Acad. Sci. U.S.A. 2014, 111, E768-E775), the present results confirm that conformational changes of MBP upon adsorption are a key for strong adhesion, and that such conformational changes are strongly dependent on the nature of the surfaces. PMID:25706854

  18. Shikimic Acid Ozonolysis is Influenced by its Physical State

    NASA Astrophysics Data System (ADS)

    Steimer, S.; Krieger, U. K.; Lampimäki, M.; Peter, T.; Ammann, M.

    2013-12-01

    behavior regarding the ozone gas phase concentration. Microspectroscopy showed that the speed at which the characteristic double bond peak of shikimic acid disappeared was humidity dependent. The measured humidity dependence supports the hypothesis that the uptake coefficient is highly dependent on the diffusion coefficients of ozone and/or shikimic acid in the organic film. [1] Nature, 2010, 467, 824-827. [2] Proc. Natl. Acad. Sci. U. S. A., 2011, 108, 11003-11008. [3] Proc. Natl. Acad. Sci. U. S. A., 2012, 109, 17354-17359.

  19. [Diet quality in college students with different academic profile].

    PubMed

    Pérez-Gallardo, Lucía; Mingo Gómez, Teresa; Bayona Marzo, Isabel; Ferrer Pascual, Ma Ángeles; Marquez Calle, Enrique; Rámirez Domínguez, Roberto; Navas Ferrer, Carlos; Navas Cámara, Francisco

    2015-05-01

    Introducción: En España son varios los estudios universitarios que abordan los temas de alimentación y estilo de vida, y demuestran que éstos son una estrategia eficaz para la prevención de enfermedades crónicas. Objetivos: Evaluar la ingesta de energía y nutrientes y la adhesión a la Dieta Mediterránea (DM) en un grupo de estudiantes universitarios con distinto perfil académico y comparar la calidad de la dieta entre estudiantes que cursan grados en Ciencias de la Salud (CS) y los de otras carreras (No CS). Métodos: 77 estudiantes (80,3% mujeres) del Campus de Soria, 37 de grados en CS y 40 de No CS de edad media 21,2 ± 2,1 años, cumplimentaron un cuestionario sobre datos socio-biográficos, el test KIDMED y registraron la ingesta de alimentos durante siete días. La estimación de la cantidad de energía y nutrientes se realizó mediante el programa informático NUTRIBER (versión 1.1.1.3r) y para la comparación de medias de muestras independientes se utilizaron las pruebas t de Student o U de Mann-Whitney y el criterio de significación se estableció en p < 0,05. Resultados y Discusión: Los estudiantes encuestados, con independencia de su perfil académico, siguen una dieta hipocalórica con mayor consumo de proteínas y de grasas de las recomendadas y menor de hidratos de carbono y fibra, lo que se refleja en el aporte insuficiente de algunas vitaminas y minerales. A pesar de ello, observamos un mayor porcentaje de encuestados con adhesión alta a los parámetros de la DM en el grupo CS (51,4%) que en el grupo no CS (30,8 %).

  20. Ras is not required for the interleukin 3-induced proliferation of a mouse pro-B cell line, BaF3.

    PubMed

    Terada, K; Kaziro, Y; Satoh, T

    1995-11-17

    It has been demonstrated that Ras is involved in interleukin 3 (IL-3)-stimulated signal transduction in various hematopoietic cultured cells (Satoh, T., Nakafuku, M., Miyajima, A., and Kaziro, Y. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 3314-3318; Duronio, V., Welham, M. J., Abraham, S., Dryden, P., and Schrader, J. W. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 1587-1591). However, it has not been fully understood which of IL-3-promoted cellular responses, i.e. proliferation, survival, and differentiation, requires Ras function. We employed a system of inducible expression of the dominant-negative (S17N) or dominant-active (G12V) mutant of Ras in BaF3 mouse pro-B cell line to analyze the role of Ras in IL-3-stimulated signal transduction. Induction of the dominant-negative Ras(S17N) effectively inhibited the IL-3-induced activation of c-Raf-1 and mitogen-activated protein kinase (MAPK). Furthermore, the activation of fos gene promoter following IL-3 stimulation was almost completely abolished when Ras(S17N) was induced. Under these conditions, Ras(S17N) exhibited no inhibitory effect on IL-3-dependent proliferation assessed by the increase of cell numbers and a mitochondrial enzyme activity. The results indicate that Ras-dependent pathways, including the Raf/MAPK/Fos pathway, are dispensable for IL-3-induced growth stimulation. When BaF3 cells were treated with a tyrosine kinase inhibitor, herbimycin A, IL-3-dependent proliferation of the cells was impaired, suggesting that tyrosine kinase-mediated pathways are critical for growth promotion. On the other hand, apoptotic cell death caused by deprivation of IL-3 was prevented by the induction of the activated mutant Ras(G12V), although the rate of cell number increase was markedly reduced. Thus, it is likely that Ras-independent pathways play important roles to facilitate the proliferation although they may not be essential for IL-3-stimulated antiapoptotic signal transduction.

  1. Alfred Vulpian and Jean-Martin Charcot in each other's shadow? From Castor and Pollux at La Salpêtrière to neurology forever.

    PubMed

    Bogousslavsky, Julien; Walusinski, Olivier; Moulin, Thierry

    2011-01-01

    While Alfred Vulpian (1826-1887) is not completely forgotten, he cannot match the uninterrupted celebrity which Jean-Martin Charcot (1825-1893) still enjoys today. After becoming interne (residents) at the same institute in 1848, both were involved in shaping the cradle of what would become modern neurology. Both started work as chiefs at a La Salpêtrière service on January 1, 1862, making common rounds and studies, with several common publications. While their friendship remained 'for life', as stated by Charcot at Vulpian's funeral, their career paths differed. Vulpian progressed quicker and higher, being appointed full professor and elected at the Académie Nationale de Médecine and the Académie des Sciences several years before Charcot, as well as becoming dean of the Paris Faculty of Medicine. These positions also enabled him to support his friend Charcot in getting appointed full clinical professor and becoming the first holder of the chair of Clinique des Maladies du Système Nerveux in 1882. Before studying medicine, Vulpian had worked in physiology with Pierre Flourens, and his career always remained balanced between physiology and neurology, with remarkable papers. He introduced Charcot to optic microscopy during their La Salpêtrière years, indirectly helping him to become his successor to the chair of pathological anatomy in 1872. While Vulpian succeeded so well in local medical affairs, Charcot spent his time building up a huge clinical service and a teaching 'school' at La Salpêtrière, which he never left for over 31 years until his death. This 'school' progressively became synonymous with clinical neurology itself and perpetuated the master's memory for decades. Vulpian never had such support, although Jules Déjerine was his pupil and Joseph Babinski was his interne before becoming Charcot's chef de clinique (chief of staff) in 1885. This unusual switch in Parisian medicine contributed to Charcot's unaltered celebrity over more than a century

  2. Low frequency electromagnetic signals in the atmosphere caused by geodynamics and solar activity

    NASA Astrophysics Data System (ADS)

    Novik, Oleg; Ruzhin, Yuri; Ershov, Sergey; Volgin, Max; Smirnov, Fedor

    Due to the composed structure of the medium and large portions of energy transferred, a seismic excitation in the oceanic or continental lithosphere disturbs all types of geophysical fields. To investigate the problem of electromagnetic (EM) forcing on the atmosphere from the seismically activated lithosphere, we have formulated two mathematical models of interaction of fields of different physical nature resulting in arising of the low-frequency (from 0.1 to 10 Hz by amplitude of a few hundreds of pT) EM signals in the atmosphere. First we have considered the EM field generation in the moving oceanic lithosphere and then in the moving continental one. For both cases, the main physical principles and geological data were applied for formulation of the model and characteristics of the computed signals of different nature agree with measurements of other authors. On the basis of the 2D model of the seismo-hydro-EM-temperature interaction in a lithosphere-Ocean-atmosphere domain, a block-scheme of a multisensory vertically distributed (from a seafloor up to the ionosphere) tsunami precursors’ detection system is described. On the basis of the 3D model of the seismo-EM interaction in a lithosphere-atmosphere domain, we explain effect of location of the future seismic epicenter area (obtained by Prof. Kopytenko, Yu. A. from Inst. IZMIRAN of Russian Acad. Sci. and co-authors) as the result of the magnetic field measurements in the atmosphere near the earth’s surface. We believe that the biosphere effects of forcing on the atmosphere may not be ignored. We formulate the result of our measurements with the system of micro-voltmeters: low-frequency EM disturbances of the atmosphere caused by solar activity (namely, geomagnetic storms with the geomagnetic index values K = 5 and K = 6), are decreasing temporarily the coherence of oscillations of the electric potentials of different points on the surface of a head, i.e. the coherence of the human brain EM processes. We are

  3. Local mobile gene pools rapidly cross species boundaries to create endemicity within global Vibrio cholerae populations.

    PubMed

    Boucher, Yan; Cordero, Otto X; Takemura, Alison; Hunt, Dana E; Schliep, Klaus; Bapteste, Eric; Lopez, Philippe; Tarr, Cheryl L; Polz, Martin F

    2011-01-01

    Vibrio cholerae represents both an environmental pathogen and a widely distributed microbial species comprised of closely related strains occurring in the tropical to temperate coastal ocean across the globe (Colwell RR, Science 274:2025-2031, 1996; Griffith DC, Kelly-Hope LA, Miller MA, Am. J. Trop. Med. Hyg. 75:973-977, 2006; Reidl J, Klose KE, FEMS Microbiol. Rev. 26:125-139, 2002). However, although this implies dispersal and growth across diverse environmental conditions, how locally successful populations assemble from a possibly global gene pool, relatively unhindered by geographic boundaries, remains poorly understood. Here, we show that environmental Vibrio cholerae possesses two, largely distinct gene pools: one is vertically inherited and globally well mixed, and the other is local and rapidly transferred across species boundaries to generate an endemic population structure. While phylogeographic analysis of isolates collected from Bangladesh and the U.S. east coast suggested strong panmixis for protein-coding genes, there was geographic structure in integrons, which are the only genomic islands present in all strains of V. cholerae (Chun J, et al., Proc. Natl. Acad. Sci. U. S. A. 106:15442-15447, 2009) and are capable of acquiring and expressing mobile gene cassettes. Geographic differentiation in integrons arises from high gene turnover, with acquisition from a locally co-occurring sister species being up to twice as likely as exchange with conspecific but geographically distant V. cholerae populations. IMPORTANCE Functional predictions of integron genes show the predominance of secondary metabolism and cell surface modification, which is consistent with a role in competition and predation defense. We suggest that the integron gene pool's distinctness and tempo of sharing are adaptive in allowing rapid conversion of genomes to reflect local ecological constraints. Because the integron is frequently the main element differentiating clinical strains

  4. Sea-level variability in tide-gauge and geological records: An empirical Bayesian analysis (Invited)

    NASA Astrophysics Data System (ADS)

    Kopp, R. E.; Hay, C.; Morrow, E.; Mitrovica, J. X.; Horton, B.; Kemp, A.

    2013-12-01

    melt [5]. We end by presenting preliminary results from such an analysis. [1] Sallenger et al. (2012), Nat. Clim. Change 2: 884-888. [2] Kopp (in press),Geophys. Res. Lett. [3] Engelhart and Horton (2011), Quat. Sci. Rev. 54: 12-25. [4] Kemp et al. (2011), Proc. Natl. Acad. Sci. 108: 11017-11022. [5] Hay et al. (2013). Proc. Natl. Acad. Sci. 110: 3692-3699.

  5. The Cloud Paradigm: Geostable molecules as proxies for surface oxygenation

    NASA Astrophysics Data System (ADS)

    Summons, R. E.; Hallmann, C.

    2011-12-01

    before the great oxidation event. Science 317, 1903-1906. (2007). Bosak T. et al., Morphological record of oxygenic photosynthesis in conical stromatolites. Proc. Natl. Acad. Sci. USA 106:10939-10943 (2009). Kopp, R.E. et al.,The Paleoproterozoic snowball Earth: A climate disaster triggered by the evolution of oxygenic photosynthesis. Proc. Natl. Acad. Sci. USA 102: 11131-11136 (2005). Waldbauer J.R. et al. Late Archean molecular fossils from the Transvaal Supergroup record the antiquity of microbial diversity and aerobiosis. Precambrian Research 169, 28-47 (2008).

  6. 3-D Raman Imagery and Atomic Force Microscopy of Ancient Microscopic Fossils

    NASA Astrophysics Data System (ADS)

    Schopf, J.

    2003-12-01

    al. (2001) Proc. Nat. Acad. Sci. USA 98: 823-826. (2) Schopf, J.W. et al. (2002) Nature 416:73-76. (3) Schopf, J.W. (2003) 7th Exobiol. PI Symp. (NASA Ames): 57. (4) Kempe, A. et al. (2002) Proc. Nat. Acad. Sci. USA 99: 9117-9120.

  7. [Rhinitis and asthma as a cause of absenteeism and poor work/school performance in a population from Latin-American tropic].

    PubMed

    Sánchez, Jorge; Estarita, Javier; Salemi, Carolina

    2016-01-01

    Antecedentes: el asma y la rinitis son las enfermedades respiratorias crónicas más frecuentes. Su alto efecto clínico se asocia con pérdidas de días laborales y menor rendimiento. Objetivo: evaluar el efecto de la rinitis y el asma como causa de ausentismo y bajo rendimiento laboral en una población de adultos y niños. Material y método: estudio trasversal, realizado en 10 escuelas de dos ciudades de Colombia. Se invitó a participar a población estudiantil entre 6 y 17 años y a los empleados mayores de 18 años de edad. A todos los participantes se les realizó un cuestionario que evaluó parámetros relacionados con la historia clínica y se hizo una revisión de las calificaciones (matemáticas y español), hojas de vida y número de ausentismos durante el último año académico completado. Resultados: aceptaron participar 1,413 personas. La frecuencia de rinitis, asma o ambas fue de 36%. Hubo mayor frecuencia de ausentismo escolar en la población infantil con síntomas respiratorios (2.8 vs 1.2 días/año/paciente, p menor a 0.01) y hubo menor rendimiento académico (reprobó: 17 vs 9%, p menor a 0.05) y laboral (0.43 vs 0.27 p menor a 0.05) en la población sintomática. Observamos que los pacientes con buen apego al tratamiento farmacológico tenían menor ausentismo y mejor rendimiento. Conclusión: la rinitis y el asma se asocian con menor desempeño en la población infantil y adulta, al igual que con mayor ausentismo en la escuela; sin embargo, el tratamiento adecuado puede mejorar el control clínico y reducir el efecto negativo a nivel laboral.

  8. Quantifying rind formation and chemical weathering rates in weathering clasts with uranium-series isotopes: a case study from Basse-Terre Island, Guadeloupe

    NASA Astrophysics Data System (ADS)

    Ma, L.; Chabaux, F. J.; Pelt, E.; Granet, M.; Sak, P. B.; Gaillardet, J.; Lebedeva, M.; Brantley, S. L.

    2011-12-01

    Weathering of tropical volcanic islands is rapid because of the reactive nature of the volcanic rock and the hot humid climate. In the tropics, rock fragments in the regolith zone commonly form alteration rinds. Weathering rinds are excellent samples to understand key chemical weathering processes. To quantify rock weathering rates in a tropical climate and to understand the environmental factors that control these rates, we combined a novel U-series isotopic technique with chemical and electron microprobe analyses to study weathering rinds formed at Basse-Terre Island, Guadeloupe. U-series isotopes and element concentrations were analyzed in a basaltic/andesitic weathering rind collected from the Bras David watershed on Basse-Terre Island. From the clast, core and rind samples were obtained by drilling along two linear profiles. Elemental profiles reveal that elemental loss varies in the order of Ca, Na, Sr > K, Mg, Rb > Mn > Si > Ba > Al > Fe, and Ti =0 across the core-rind interface, consistent with relative reactivity of phases in the clast from plagioclase ≈ pyroxene ≈ glass matrix > apatite > ilmenite. Elemental profiles also reveal conservative behavior of Th and external addition of U into the rind during clast weathering. Measured (234U/238U) activity ratios of the rind samples (1.001 to 1.031) are mostly higher than the core samples (average at ~1.003). Measured (238U/232Th) and (230Th/232Th) activity ratios of the core and rind samples range from 0.973 to 1.817, and 0.971 to 1.375, respectively. Most importantly, both (238U/232Th) and (230Th/232Th) activity ratios increase systematically from the core into the weathering rind for the two profiles. The elemental profiles and electronic microprobe observations suggest that weathering reactions include dissolution of pyroxene, plagioclase, and glass matrix, and formation of Fe oxyhydroxides, gibbsite and minor kaolinite. The dissolution of plagioclase leads to significant porosity growth within the rind

  9. The Development of Plasma Thrusters and Its Importance for Space Technology and Science Education at University of Brasilia

    NASA Astrophysics Data System (ADS)

    Ferreira, Jose Leonardo; Calvoso, Lui; Gessini, Paolo; Ferreira, Ivan

    Since 2004 The Plasma Physics Laboratory of University of Brasilia (Brazil) is developing Hall Plasma Thurusters for Satellite station keeping and orbit control. The project is supported by CNPq, CAPES, FAP DF and from The Brazillian Space Agency-AEB. The project is part of The UNIESPAÇO Program for Space Activities Development in Brazillian Universities. In this work we are going to present the highlights of this project together with its vital contribution to include University of Brasilia in the Brazillian Space Program. Electric propulsion has already shown, over the years, its great advantages in being used as main and secondary thruster system of several space mission types. Between the many thruster concepts, one that has more tradition in flying real spacecraft is the Hall Effect Thruster (HET). These thrusters, first developed by the USSR in the 1960s, uses, in the traditional design, the radial magnetic field and axial electric field to trap electrons, ionize the gas and accelerate the plasma to therefore generate thrust. In contrast to the usual solution of using electromagnets to generate the magnetic field, the research group of the Plasma Physics Laboratory of University of Brasília has been working to develop new models of HETs that uses combined permanent magnets to generate the necessary magnetic field, with the main objective of saving electric power in the final system design. Since the beginning of this research line it was developed and implemented two prototypes of the Permanent Magnet Hall Thruster (PMHT). The first prototype, called P-HALL1, was successfully tested with the using of many diagnostics instruments, including, RF probe, Langmuir probe, Ion collector and Ion energy analyzer. The second prototype, P-HALL2, is currently under testing, and it’s planned the increasing of the plasma diagnostics and technology analysis, with the inclusion of a thrust balance, mass spectroscopy and Doppler broadening. We are also developing an

  10. Geostatistical Sampling Methods for Efficient Uncertainty Analysis in Flow and Transport Problems

    NASA Astrophysics Data System (ADS)

    Liodakis, Stylianos; Kyriakidis, Phaedon; Gaganis, Petros

    2015-04-01

    surface of a M-dimensional, unit radius hyper-sphere, (ii) relocating the N points on a representative set of N hyper-spheres of different radii, and (iii) transforming the coordinates of those points to lie on N different hyper-ellipsoids spanning the multivariate Gaussian distribution. The above method is applied in a dimensionality reduction context by defining flow-controlling points over which representative sampling of hydraulic conductivity is performed, thus also accounting for the sensitivity of the flow and transport model to the input hydraulic conductivity field. The performance of the various stratified sampling methods, LH, SL, and ME, is compared to that of SR sampling in terms of reproduction of ensemble statistics of hydraulic conductivity and solute concentration for different sample sizes N (numbers of realizations). The results indicate that ME sampling constitutes an equally if not more efficient simulation method than LH and SL sampling, as it can reproduce to a similar extent statistics of the conductivity and concentration fields, yet with smaller sampling variability than SR sampling. References [1] Gutjahr A.L. and Bras R.L. Spatial variability in subsurface flow and transport: A review. Reliability Engineering & System Safety, 42, 293-316, (1993). [2] Helton J.C. and Davis F.J. Latin hypercube sampling and the propagation of uncertainty in analyses of complex systems. Reliability Engineering & System Safety, 81, 23-69, (2003). [3] Switzer P. Multiple simulation of spatial fields. In: Heuvelink G, Lemmens M (eds) Proceedings of the 4th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences, Coronet Books Inc., pp 629?635 (2000).

  11. Developing first time-series of land surface temperature from AATSR with uncertainty estimates

    NASA Astrophysics Data System (ADS)

    Ghent, Darren; Remedios, John

    2013-04-01

    . The uncertainty analysis takes into account the expected performance of the retrieval algorithm under varying surface and atmospheric conditions. We characterise the uncertainties in terms of: radiometric noise; fractional vegetation cover as representative of surface emissivity; atmospheric water vapour; and uncertainties as a result of the coefficient fitting process. The total uncertainty budget is a combination of these four components added together in quadrature. The uncertainty due to misclassification of cloudy pixels is difficult to propagate to LST uncertainty bars and has yet to be evaluated in the framework of the current study. The progress made here will allow other time series of LST to be compared with the record from AATSR with greater certainty and hence increases confidence in our knowledge of recent surface temperature changes over the land. References Ghent, D., Corlett, G., and Remedios, J. Advancing the AATSR land surface temperature retrieval with higher resolution auxiliary datasets, in prep. Kogler, C., Pinnock, S., Arino, O., Casadio, S., Corlett, G., Prata, F., and Bras, T. Note on the quality of the (A)ATSR land surface temperature record from 1991 to 2009, International Journal of Remote Sensing, 33, 4178-4192, 2012

  12. Recent studies on UV radiation in Brazil

    NASA Astrophysics Data System (ADS)

    Correa, M. P.; Ceballos, J. C.; Moregula, A.; Okuno, E.; Fausto, A.; Mol, A.; Santos, J. C.

    2009-04-01

    < 11) and Extreme (UVI ≥ 11). Under clear-sky conditions it has been constantly high in all the Brazilian territories. Maximum UVI recorded: São Paulo (2005-2008): 17.2; Itajubá: 15.5; and Ilhéus: 13.6. Even during winter, measurements constantly reach values around UVI = 6. São Paulo is appreciably touched for these high UV radiation levels to have a population very exposed during its quotidian. In the popular culture, an urban site is not popularly considered as a sunny place. In other words, for a large part of the Brazilian population, São Paulo or Itajubá are perceived as places where the risk to the sun overexposure is relatively low. These recent results are being used as basis for educational programs to teach the population about precautions to be taken during sun exposure. Acknowledgments: This study was supported by FAPEMIG (Minas Gerais, Brazil), FAPESP (São Paulo, Brazil) and CNPq (Brasília, Brazil).

  13. GRID integration of oceanographic remote instrumentation

    NASA Astrophysics Data System (ADS)

    Salon, S.; Bolzon, G.; Mauri, E.; Poulain, P.-M.

    2009-04-01

    OGS. The main goal of DORII is the deployment of an eInfrastructure for those scientific communities where ICT technology and the concept of GRID is perceived as a big opportunity to boost their research but that, at present, results not fully exploited. The oceanographic community may greatly benefit from the resources being offered by the GRID technology, in particular concerning the data driven control/interaction workflow and the post-processing/visualization issues that characterize the remote instruments. [1] N.C. Flemming, S. Vallerga, N. Pinardi, H.W.A. Behrens, G. Manzella, D. Prandle and J.H. Stel (eds), Operational Oceanography - Implementation at the European and Regional Scales, Elsevier Oceanography Vol. 66. Elsevier, Amsterdam (2002). [2] http://poseidon.ogs.trieste.it/sire/medargo [3] P.-M. Poulain, R. Barbanti, J. Font, A. Cruzado, C. Millot, I. Gertman, A. Griffa, A. Molcard, V. Rupolo, S. Le Bras and L. Petit de la Villeon, MedArgo: a drifting profiler program in the Mediterranean Sea, Ocean Science 3, 379-395 (2007). [4] http://www.dorii.eu/home

  14. The efficacy of exercise therapy in reducing shoulder pain related to breast cancer: a systematic review.

    PubMed

    Tatham, Barbara; Smith, Jenna; Cheifetz, Oren; Gillespie, Jessica; Snowden, Katie; Temesy, Jessica; Vandenberk, Lisa

    2013-01-01

    Objectif : Des recherches récentes indiquent que les interventions de physiothérapie comme l'exercice et la thérapie manuelle peuvent être efficaces pour réduire la fréquence des effets secondaires liés au traitement du cancer du sein, y compris la fatigue, la douleur, les nausées et une baisse de la qualité de vie. Cette critique systématique vise à déterminer l'efficacité de la thérapie par l'exercice lorsqu'il s'agit d'atténuer une douleur à l'épaule liée à un traitement du cancer du sein et à déterminer les mesures de résultat qu'il est possible d'utiliser pour évaluer la douleur à l'épaule dans cette population. Méthode : On a procédé à un examen systématique des publications courantes en utilisant des portails comme PEDro, CINAHL, PubMed, Ovid MEDLINE (1996 à avril 2011) et AMED (1985 à avril 2011). On a cherché dans des bases de données des études pertinentes publiées jusqu'en avril 2011. Les participants aux études pertinentes étaient des adultes (≥18 ans) qui avaient reçu un diagnostic primaire de cancer du sein à n'importe quel moment au cours du traitement de leur maladie. Résultats : Six articles ont fait l'objet d'examens à l'aveugle effectués par des examinateurs indépendants. Six études ont satisfait aux critères d'inclusion, chacune analysant des types différents d'exercice—renforcement/stabilisation de l'épaule, du bras ou de l'omoplate, exercices posturaux, exercices généraux et conditionnement, exercices portant sur l'amplitude du mouvement de l'épaule et exercices contre le lymphœdème—en ce qui a trait à leur efficacité pour réduire la douleur à l'épaule liée au traitement du cancer du sein. Conclusions : Les résultats indiquent que les exercices prescrits contre la douleur à l'épaule liée au traitement du cancer du sein peuvent être efficaces. On n'a pu toutefois tirer de conclusions définitives parce que les études incluses manquaient de qualité méthodologique et

  15. Variation of Slope-Area Relationship Caused by a Catastrophic Landslide

    NASA Astrophysics Data System (ADS)

    Tseng, Chih-Ming; Lin, Ching-Weei; Dalla Fontana, Giancarlo; Tarolli, Paolo

    2013-04-01

    significantly changed the earth surface. References Montgomery, D.R., Foufoula-Georgiou, E., 1993. Channel network source representation using digital elevation models. Water Resour. Res. 29, 3925-3934. Lin, C.W., Chang, W.S., Liu, S.H., Tsai, T.T., Lee, S.P., Tsang, Y.C., Shieh, C.L., Tseng, C.M., 2011. Landslides triggered by the 7 August 2009 Typhoon Morakot in Southern Taiwan. Engineering Geology 123, 3-12. Tarolli, P., Dalla Fontana, G., 2009. Hillslope-to-valley transition morphology: new opportunities from high resolution DTMs, Geomorphology, 113, 47-56, doi:10.1016/j.geomorph.2009.02.006. Tsou, C.-Y., Feng, Z.-Y., Chigira, M., 2011. Catastrophic landslide induced by Typhoon Morakot, Shiaolin, Taiwan. Geomorphology 127, 166-178, doi:10.1016/j.geomorph.2010.12.013. Tucker, G.E., Bras, R.L., 1998. Hillslope processes, drainage density, and landscape morphology. Water Resour. Res. 34, 2751-2764. Wu, C. H., Chen, S. C., Chou, H. T., (2011). Geomorphologic characteristics of catastrophic landslides during typhoon Morakot in the Kaoping Watershed, Taiwan, Engineering Geology 123(1-2), 13-21, doi: 10.1016/j.enggeo.2011.04.018.

  16. PREFACE Proceedings of the XIV International Conference on Small-Angle Scattering, SAS-2009

    NASA Astrophysics Data System (ADS)

    King, Stephen; Terrill, Nicholas

    2010-10-01

    scientific heart of the conference comprised 10 plenary sessions, interspersed by 39 'themed' parallel sessions, 2 poster sessions, an afternoon tour of Diamond and ISIS, and a week-long exhibition. There were 144 contributed oral presentations and 308 poster presentations across a total of 21 themes. Over half of all presentations fell under 6 themes: biological systems, colloids and solutions, instrumentation, kinetic and time-resolved measurements, polymers, and surfaces and interfaces. The importance of SAS techniques to the study of biology, materials science and soft matter/nanoscience is clear. The plenary presentations, which covered topics as diverse as advanced analysis techniques, biology, green chemistry, materials science and surfaces, were delivered by Frank Bates, Minnesota, USA, Peter Fratzl, MPI Golm, Germany, Buxing Han, Bejing, China, Julia Kornfield, CIT, USA, Jan Skov Pedersen, Aarhus, Denmark, Moonhor Ree, Pohang, Korea, Mitsuhiro Shibayama, Tokyo, Japan, Robert Thomas, Oxford, UK, Jill Trewhella, Sydney, Australia, and Thomas Zemb, ICSM Bagnols, France. Instigated by representatives of the Belgian and Dutch SAS communities one parallel session was dedicated to a tribute for Michel Koch, the pioneer of so many novel applications of SAXS, who retired after 30 years at the EMBL Hamburg in late 2006. With a supporting cast that included Wim Bras, ESRF, France, Tony Ryan, Sheffield, UK and Joe Zaccai, ILL,France, and watched by former colleague André Gabriel, Michel treated the audience to a fascinating - and at times light-hearted - retrospective of the evolution of synchrotron SAXS. Another parallel session was devoted to the work of the canSAS (Collective Action for Nomadic Small-Angle Scatterers) network of large-facility representatives and instrument scientists in areas such as data file formats, intensity calibration and software development. For further information see http://www.smallangles.net/wgwiki/index.php/canSAS_Working_Groups. A total of

  17. Motility states in bidirectional cargo transport

    NASA Astrophysics Data System (ADS)

    Klein, Sarah; Appert-Rolland, Cécile; Santen, Ludger

    2015-09-01

    Intracellular cargos which are transported by molecular motors move stochastically along cytoskeleton filaments. In particular for bidirectionally transported cargos it is an open question whether the characteristics of their motion can result from pure stochastic fluctuations or whether some coordination of the motors is needed. The results of a mean-field (MF) model of cargo-motors dynamics proposed by Müller et al. (Müller M. J. et al., Proc. Natl. Acad. Sci. U.S.A., 105 (2008) 4609) suggest the existence of states which are characterized by a symmetric bimodal distribution of cargo velocities. These states would result from a stochastic tug of war. Here we analyze the influence of the MF assumption on the cargo motion by considering a model that takes explicitly the position of each motor into account. We find that those states with symmetric bimodal distributions then disappear. As the MF model implicitly assumes some stepping synchronization between motors, we introduce a partial synchronization via an artificial mutual motor-motor activation, and show that the results of the MF model are then recovered but, even in this favorable case, only in the limit of a strong motor-motor activation and of a high number of motors. We conclude that the MF assumption is not relevant for intracellular transport.

  18. Primary structure of pregnancy zone protein. Molecular cloning of a full-length PZP cDNA clone by the polymerase chain reaction.

    PubMed

    Devriendt, K; Van den Berghe, H; Cassiman, J J; Marynen, P

    1991-01-17

    A full-length cDNA clone of the human pregnancy zone protein (PZP) was cloned from the hepatocellular carcinoma cell line Hep3B. Based on the exon sequences of the PZP gene (Devriendt et al. (1989) Gene 81, 325-334; Marynen et al., unpublished data), primer pairs were designed to amplify six overlapping fragments of the PZP cDNA. The obtained cDNA is 4609 bp long and contains an open reading frame coding for 1482 amino acids, including a signal peptide of 25 amino acid residues. Comparison with the published partial PZP amino acid sequence (Sottrup-Jensen et al. (1984) Proc. Natl. Acad. Sci. USA 81, 7353-7357) and the PZP genomic sequences confirmed the identity as a PZP cDNA. 71% of the corresponding amino acid residues in PZP and human alpha 2-macroglobulin (alpha 2M) are identical and all cysteine residues are conserved. A typical internal thiol ester site and a bait domain were identified. A Pro/Thr polymorphism was identified at amino acid position 1180, and an A/G nucleotide polymorphism at bp 4097.

  19. Crystal structures and molecular mechanism of a light-induced signaling switch: The Phot-LOV1 domain from Chlamydomonas reinhardtii.

    PubMed

    Fedorov, Roman; Schlichting, Ilme; Hartmann, Elisabeth; Domratcheva, Tatjana; Fuhrmann, Markus; Hegemann, Peter

    2003-04-01

    Phot proteins (phototropins and homologs) are blue-light photoreceptors that control mechanical processes like phototropism, chloroplast relocation, or guard-cell opening in plants. Phot receptors consist of two flavin mononucleotide (FMN)-binding light, oxygen, or voltage (LOV) domains and a C-terminal serine/threonine kinase domain. We determined crystal structures of the LOV1 domain of Phot1 from the green alga Chlamydomonas reinhardtii in the dark and illuminated state to 1.9 A and 2.8 A resolution, respectively. The structure resembles that of LOV2 from Adiantum (Crosson, S. and K. Moffat. 2001. PROC: Natl. Acad. Sci. USA. 98:2995-3000). In the resting dark state of LOV1, the reactive Cys-57 is present in two conformations. Blue-light absorption causes formation of a proposed active signaling state that is characterized by a covalent bond between the flavin C4a and the thiol of Cys-57. There are differences around the FMN chromophore but no large overall conformational changes. Quantum chemical calculations based on the crystal structures revealed the electronic distribution in the active site during the photocycle. The results suggest trajectories for electrons, protons, and the active site cysteine and offer an interpretation of the reaction mechanism. PMID:12668455

  20. Kinetic studies on the control of the bean rust fungus (Uromyces phaseoli L.) by an inhibitor of polyamine biosynthesis

    NASA Technical Reports Server (NTRS)

    Rajam, M. V.; Weinstein, L. H.; Galston, A. W.

    1986-01-01

    alpha-Difluoromethylornithine (DFMO), a specific and irreversible inhibitor of the polyamine biosynthetic enzyme ornithine decarboxylase, effectively inhibits mycelial growth of several phytopathogenic fungi on defined media in vitro and provides systemic protection of bean plants against infection by Uromyces phaseoli L. race 0 (MV Rajam, AW Galston 1985 Plant Cell Physiol 26: 683-692; MV Rajam et al. 1985 Proc Natl Acad Sci USA 82: 6874-6878). We now find that application of 0.5 millimolar DFMO to unifoliolate leaves of Pinto beans up to 3 days after inoculation with uredospores of U. phaseoli completely inhibits the growth of the pathogen, while application 4 or 5 days after inoculation results in partial protection against the pathogen. Spores do not germinate on the surface of unifoliolate leaves treated with DFMO 1 day before infection, but addition of spermidine to the DFMO treatments partially reverses the inhibitory effect. The titer of polyamines in bean plants did not decline after DFMO treatment; rather, putrescine and spermidine contents actually rose, probably due to the known but paradoxical stimulation of arginine decarboxylase activity by DFMO.

  1. Heterochirality in Langmuir monolayers and antiferromagnetic Blume-Emery-Griffiths model

    NASA Astrophysics Data System (ADS)

    Pelizzola, A.; Pretti, M.; Scalas, E.

    2000-05-01

    Chirality is quite a common property in organic molecules. Chiral molecules exist in two forms (called enantiomers) which cannot be superimposed by rotations and translations and may have very different biochemical properties. Experiments on Langmuir monolayers made up of chiral amphiphiles have shown that, in most cases, heterochiral interactions dominate, implying the formation of a racemic compound. It has been shown that a monolayer mixture of two enantiomers can be simply described by a two-dimensional (2-D) spin-1 lattice gas [Blume-Emery-Griffiths (BEG) model], where the heterochiral preference is represented by an effective antiferromagnetic coupling. By now just mean field calculations have been performed on this model. Here we present a revisitation of the tripod amphiphile model, proposed by Andelman and de Gennes [D. Andelman and P.-G. de Gennes, Compt. Rend. Acad. Sci. (Paris) 307, 233 (1988)], together with a rigorous proof of the heterochiral preference shown by the model in the hypothesis of van der Waals interactions. Moreover, a cluster variation analysis of the antiferromagnetic BEG model on a triangular lattice is performed and possible interpretations in terms of surface pressure-concentration phase diagrams for monolayer mixtures of enantiomers are discussed. The choice of a triangular lattice has been suggested by the triangularlike structure of condensed phases of Langmuir monolayers, shown by x-ray diffraction experiments.

  2. Structural evolution of the Ural-Tian Shan junction: A view from Karatau ridge, South Kazakhstan

    USGS Publications Warehouse

    Alexeiev, D.V.; Cook, H.E.; Buvtyshkin, V.M.; Golub, L.Y.

    2009-01-01

    The deformation history of the Late Palaeozoic Ural-Tian Shan junction is discussed for the example of the Karatau ridge in southern Kazakhstan. Three deformation events are recognized. The Late Carboniferous D1 event is characterized by Laramide-style thrust-and-fold structures on the southern margin of Kazakhstan with shortening in a NE-SW direction. The Latest Permian and Triassic D2 event is controlled by compression in an east-west direction, which reflects collisional deformation in the Urals. The main structures are submeridional folds and north-west-striking sinistral strike-slip faults. The Triassic D3 event with shortening in a north-south direction reflects collision of the Turan microcontinent against the southern margin of Kazakhstan. The main structures are north-west-striking dextral strike-slip faults. Our new data provides important clues for the reconstruction of pre-Cretaceous structures between the Urals and the Tian Shan. ?? 2008 Acad??mie des sciences.

  3. Photosynthetic glow peaks and their relationship with the free energy changes.

    PubMed

    Devault, D; Govindjee

    1990-05-01

    This paper is concerned with relating thermoluminescence to the total free-energy change, ΣG, involved in detrapping a particular electron-hole pair as a photosynthetic sample is warmed from an initial low temperature. It extends a mathematical discussion of four possible mechanisms introduced in an earlier paper [DeVault, Govindjee and Arnold, Proc Nat'l Acad Sci USA 80: 983-987 (1983)]; here, particular attention is paid to the dependence of the absolute temperature of the maximum of a glow-peak, T m , on the total free-energy change, ΣG. The conclusion from the cases studied is that T m =ΣG/(k B W) where ΣG is evaluated at T m , W is a complicated function of temperature and of thermodynamic parameters in the steps of the mechanism, and k B is the Boltzmann constant. If the rate limiting step in the mechanism of detrapping is not preceded by any step in which ΔG is appreciably negative, W is likely to have a value of about 33 and T m is approximately proportional to ΣG. Otherwise W can become much smaller and more strongly dependent on temperature and T m is no longer proportional to ΣG. These conclusions are of significance in lending theoretical support to the practice of inferring redox midpoint potential changes from shifts in T m .

  4. Adaptive elastic networks as models of supercooled liquids

    NASA Astrophysics Data System (ADS)

    Yan, Le; Wyart, Matthieu

    2015-08-01

    The thermodynamics and dynamics of supercooled liquids correlate with their elasticity. In particular for covalent networks, the jump of specific heat is small and the liquid is strong near the threshold valence where the network acquires rigidity. By contrast, the jump of specific heat and the fragility are large away from this threshold valence. In a previous work [Proc. Natl. Acad. Sci. USA 110, 6307 (2013), 10.1073/pnas.1300534110], we could explain these behaviors by introducing a model of supercooled liquids in which local rearrangements interact via elasticity. However, in that model the disorder characterizing elasticity was frozen, whereas it is itself a dynamic variable in supercooled liquids. Here we study numerically and theoretically adaptive elastic network models where polydisperse springs can move on a lattice, thus allowing for the geometry of the elastic network to fluctuate and evolve with temperature. We show numerically that our previous results on the relationship between structure and thermodynamics hold in these models. We introduce an approximation where redundant constraints (highly coordinated regions where the frustration is large) are treated as an ideal gas, leading to analytical predictions that are accurate in the range of parameters relevant for real materials. Overall, these results lead to a description of supercooled liquids, in which the distance to the rigidity transition controls the number of directions in phase space that cost energy and the specific heat.

  5. Polynucleotide phosphorylase negatively controls spv virulence gene expression in Salmonella enterica.

    PubMed

    Ygberg, Sofia Eriksson; Clements, Mark O; Rytkönen, Anne; Thompson, Arthur; Holden, David W; Hinton, Jay C D; Rhen, Mikael

    2006-02-01

    Mutational inactivation of the cold-shock-associated exoribonuclease polynucleotide phosphorylase (PNPase; encoded by the pnp gene) in Salmonella enterica serovar Typhimurium was previously shown to enable the bacteria to cause chronic infection and to affect the bacterial replication in BALB/c mice (M. O. Clements et al., Proc. Natl. Acad. Sci. USA 99:8784-8789, 2002). Here, we report that PNPase deficiency results in increased expression of Salmonella plasmid virulence (spv) genes under in vitro growth conditions that allow induction of spv expression. Furthermore, whole-genome microarray-based transcriptome analyses of bacteria growing inside murine macrophage-like J774.A.1 cells revealed six genes as being significantly up-regulated in the PNPase-deficient background, which included spvABC, rtcB, entC, and STM2236. Mutational inactivation of the spvR regulator diminished the increased expression of spv observed in the pnp mutant background, implying that PNPase acts upstream of or at the level of SpvR. Finally, competition experiments revealed that the growth advantage of the pnp mutant in BALB/c mice was dependent on spvR as well. Combined, our results support the idea that in S. enterica PNPase, apart from being a regulator of the cold shock response, also functions in tuning the expression of virulence genes and bacterial fitness during infection. PMID:16428774

  6. Neurite outgrowth of neuroblastoma cells overexpressing alpha and beta isoforms of Ca2+/calmodulin-dependent protein kinase II-effects of protein kinase inhibitors.

    PubMed

    Yamauchi, T; Yoshimura, Y; Nomura, T; Fujii, M; Sugiura, H

    1998-06-01

    Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) is one of the most abundant protein kinases in the brain and has a broad substrate specificity [M.K. Bennett, N.E. Erondu, M.B. Kennedy, Purification and characterization of a calmodulin-dependent protein kinase that is highly concentrated in brain, J. Biol. Chem. 258 (1983) 12735-12744 [1]; J.R. Goldenring, B. Gonzalez, J.S. McGuire, Jr., R.J. DeLorenzo, Purification and characterization of a calmodulin-dependent kinase from rat brain cytosol able to phosphorylate tubulin and microtubule-associated proteins, J. Biol. Chem. 258 (1983) 12632-12640 [4]; M.B. Kennedy, P. Greengard, Two calcium/calmodulin-dependent protein kinases, which are highly concentrated in brain, phosphorylate protein I at distinct sites, Proc. Natl. Acad. Sci. U.S.A. 78 (1981) 1293-1297 [10]; T. Yamauchi, H. Fujisawa, Evidence for three distinct forms of calmodulin-dependent protein kinases from rat brain, FEBS Lett. 116 (1980) 141-144 [20]; T. Yamauchi, H. Fujisawa, Purification and characterization of the brain calmodulin-dependent protein kinase (kinase II), which is involved in the activation of tryptophan 5-monooxygenase, Eur. J. Biochem. 132 (1983) 15-21 [21

  7. Modelling the 2-kinase domain of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase on adenylate kinase.

    PubMed Central

    Bertrand, L; Vertommen, D; Depiereux, E; Hue, L; Rider, M H; Feytmans, E

    1997-01-01

    Simultaneous multiple alignment of available sequences of the bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase revealed several segments of conserved residues in the 2-kinase domain. The sequence of the kinase domain was also compared with proteins of known three-dimensional structure. No similarity was found between the kinase domain of 6-phosphofructo-2-kinase and 6-phosphofructo-1-kinase. This questions the modelling of the 2-kinase domain on bacterial 6-phosphofructo-1-kinase that has previously been proposed [Bazan, Fletterick and Pilkis (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 9642-9646]. However, sequence similarities were found between the 2-kinase domain and several nucleotide-binding proteins, the most similar being adenylate kinase. A structural model of the 2-kinase domain based on adenylate kinase is proposed. It accommodates all the results of site-directed mutagenesis studies carried out to date on residues in the 2-kinase domain. It also allows residues potentially involved in catalysis and/or substrate binding to be predicted. PMID:9032445

  8. A three-dimensional statistical mechanical model of folding double-stranded chain molecules

    NASA Astrophysics Data System (ADS)

    Zhang, Wenbing; Chen, Shi-Jie

    2001-05-01

    Based on a graphical representation of intrachain contacts, we have developed a new three-dimensional model for the statistical mechanics of double-stranded chain molecules. The theory has been tested and validated for the cubic lattice chain conformations. The statistical mechanical model can be applied to the equilibrium folding thermodynamics of a large class of chain molecules, including protein β-hairpin conformations and RNA secondary structures. The application of a previously developed two-dimensional model to RNA secondary structure folding thermodynamics generally overestimates the breadth of the melting curves [S-J. Chen and K. A. Dill, Proc. Natl. Acad. Sci. U.S.A. 97, 646 (2000)], suggesting an underestimation for the sharpness of the conformational transitions. In this work, we show that the new three-dimensional model gives much sharper melting curves than the two-dimensional model. We believe that the new three-dimensional model may give much improved predictions for the thermodynamic properties of RNA conformational changes than the previous two-dimensional model.

  9. Proof of physical exchange of genes on the chromosomes.

    PubMed

    Coe, Edward; Kass, Lee B

    2005-05-10

    Seventy-five years ago, a convincing demonstration that the genes were physically aligned along the chromosome was lacking. Harriet Creighton (1909-2004) and Barbara McClintock (1902-1992) [Creighton, H. B. & McClintock, B. (1931) Proc. Natl. Acad. Sci. USA 17, 492-497] showed by an elegantly simple experiment in 1931 that exchange between genes was accompanied by exchange of cytological, i.e., physical, parts of chromosomes. The work has been acclaimed as one of the great experiments in biology. Creighton's doctoral dissertation under McClintock's mentorship provided the basis for the landmark paper, which was unique in merging cytological with genetic data. A companion paper by McClintock, printed and bound back-to-back with the joint paper, set the essential stage with data on the cytological and genetic features that Creighton applied. Following directly from this work, and leading to today's recognition that the genome is a graspable entity, was the knowledge that the genes could be studied as components of a linear structure, the chromosome. Here, we review the data surrounding the Creighton and McClintock paper and provide a perspective on the significance of their findings. PMID:15867161

  10. Comparative hydrogen-deuterium exchange for a mesophilic vs thermophilic dihydrofolate reductase at 25 °C: identification of a single active site region with enhanced flexibility in the mesophilic protein.

    PubMed

    Oyeyemi, Olayinka A; Sours, Kevin M; Lee, Thomas; Kohen, Amnon; Resing, Katheryn A; Ahn, Natalie G; Klinman, Judith P

    2011-09-27

    The technique of hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) has been applied to a mesophilic (E. coli) dihydrofolate reductase under conditions that allow direct comparison to a thermophilic (B. stearothermophilus) ortholog, Ec-DHFR and Bs-DHFR, respectively. The analysis of hydrogen-deuterium exchange patterns within proteolytically derived peptides allows spatial resolution, while requiring a series of controls to compare orthologous proteins with only ca. 40% sequence identity. These controls include the determination of primary structure effects on intrinsic rate constants for HDX as well as the use of existing 3-dimensional structures to evaluate the distance of each backbone amide hydrogen to the protein surface. Only a single peptide from the Ec-DHFR is found to be substantially more flexible than the Bs-DHFR at 25 °C in a region located within the protein interior at the intersection of the cofactor and substrate-binding sites. The surrounding regions of the enzyme are either unchanged or more flexible in the thermophilic DHFR from B. stearothermophilus. The region with increased flexibility in Ec-DHFR corresponds to one of two regions previously proposed to control the enthalpic barrier for hydride transfer in Bs-DHFR [Oyeyemi et al. (2010) Proc. Natl. Acad. Sci. U.S.A. 107, 10074]. PMID:21859100

  11. Scavenger receptor of human monocytic leukemia cell line (THP-1) and murine macrophages for nonenzymatically glycosylated proteins.

    PubMed

    Takata, K; Horiuchi, S; Araki, N; Shiga, M; Saitoh, M; Morino, Y

    1989-11-17

    Long-term incubation of proteins with glucose undergo a series of nonenzymatic reactions to form advanced glycosylation end product (AGE) with fluorescence and brown color. The receptor for AGE-proteins was demonstrated in murine macrophages (Vlassara et al. (1985) Proc. Natl. Acad. Sci. USA 82. 5588). Our recent study with rat macrophages revealed that the receptor also recognized proteins modified with aliphatic aldehydes such as formaldehyde or glycolaldehyde, indicating its close identity to a scavenger receptor for aldehyde-modified proteins (Takata, K. et al. (1988) J. Biol. Chem. 263. 14819). This notion was tested in the present study with human monocytic leukemia cell line (THP-1 cells), human monocyte macrophages and murine peritoneal macrophages. Endocytic uptake of AGE-proteins and aldehyde-modified proteins was inhibited in a cross-competitive fashion. The receptor activities of THP-1 cells for AGE-albumin and aldehyde-modified proteins were induced synchronously by phorbol 12-myristate 13-acetate. Furthermore, upon reduction by NaBH4 of the Schiff base formed between proteins and glucose or aldehydes, no ligand activity was generated. However, once the ligand activity was generated, NaBH4 was no longer effective for the ligand activity. Thus, a structure in common between AGE-proteins and aldehyde-modified proteins may be crucial for recognition by the human macrophage receptor.

  12. Lithium-Boron (Li-B) Monolayers: First-Principles Cluster Expansion and Possible Two-Dimensional Superconductivity.

    PubMed

    Wu, Chao; Wang, Hua; Zhang, Jiajia; Gou, Gaoyang; Pan, Bicai; Li, Ju

    2016-02-01

    Recent works demonstrated that the superconductivity at two-dimensional (2-D) can be achieved in Li-decorated graphene (Nature Phys. 2012, 8, 131 and Proc. Natl. Acad. Sci. 2015, 112, 11795). Inspired by the progress made in graphene, we predict by using the first-principles calculations that Li-incorporated B monolayers (Li-B monolayers) can be alternative 2-D superconductors. First-principles cluster expansion approach was used to evaluate the structural diversity and energetic stability of the 2-D Li-B monolayers by treating them as ternary Lix⬡yB1-x-y pseudoalloys (⬡ refers to B hexagonal hole). After thoroughly exploring the Li-B configuration space, several well-ordered and stable Li-B monolayers were identified. Detailed analyses regarding the electronic structures and lattice dynamics properties of the predicted Li-B monolayers were performed. Compared with the non-superconducting pure B-sheet, some predicted Li-B monolayers can exhibit the phonon-mediated superconducting properties above the liquid helium temperature.

  13. aCHEdb: the database system for ESTHER, the alpha/beta fold family of proteins and the Cholinesterase gene server.

    PubMed

    Cousin, X; Hotelier, T; Giles, K; Toutant, J P; Chatonnet, A

    1998-01-01

    Acetylcholinesterase belongs to a family of proteins, the alpha/beta hydrolase fold family, whose constituents evolutionarily diverged from a common ancestor and share a similar structure of a central beta sheet surrounded by alpha helices. These proteins fulfil a wide range of physiological functions (hydrolases, adhesion molecules, hormone precursors) [Krejci,E., Duval,N., Chatonnet,A., Vincens,P. and Massoulié,J. (1991) Proc. Natl. Acad. Sci. USA , 88, 6647-6651]. ESTHER (for esterases, alpha/beta hydrolase enzymes and relatives) is a database aimed at collecting in one information system, sequence data together with biological annotations and experimental biochemical results related to the structure-function analysis of the enzymes of the family. The major upgrade of the database comes from the use of a new database management system: aCHEdb which uses the ACeDB program designed by Richard Durbin and Jean Thierry-Mieg. It can be found at http://www.ensam.inra.fr/cholinesterase

  14. Geologic carbon storage is unlikely to trigger large earthquakes and reactivate faults through which CO2 could leak.

    PubMed

    Vilarrasa, Victor; Carrera, Jesus

    2015-05-12

    Zoback and Gorelick [(2012) Proc Natl Acad Sci USA 109(26):10164-10168] have claimed that geologic carbon storage in deep saline formations is very likely to trigger large induced seismicity, which may damage the caprock and ruin the objective of keeping CO2 stored deep underground. We argue that felt induced earthquakes due to geologic CO2 storage are unlikely because (i) sedimentary formations, which are softer than the crystalline basement, are rarely critically stressed; (ii) the least stable situation occurs at the beginning of injection, which makes it easy to control; (iii) CO2 dissolution into brine may help in reducing overpressure; and (iv) CO2 will not flow across the caprock because of capillarity, but brine will, which will reduce overpressure further. The latter two mechanisms ensure that overpressures caused by CO2 injection will dissipate in a moderate time after injection stops, hindering the occurrence of postinjection induced seismicity. Furthermore, even if microseismicity were induced, CO2 leakage through fault reactivation would be unlikely because the high clay content of caprocks ensures a reduced permeability and increased entry pressure along the localized deformation zone. For these reasons, we contend that properly sited and managed geologic carbon storage in deep saline formations remains a safe option to mitigate anthropogenic climate change.

  15. Polypyrimidine Tract-Binding Protein Binds to the Leader RNA of Mouse Hepatitis Virus and Serves as a Regulator of Viral Transcription

    PubMed Central

    Li, Hsin-Pai; Huang, Peiyong; Park, Sungmin; Lai, Michael M. C.

    1999-01-01

    A cellular protein, previously described as p55, binds specifically to the plus strand of the mouse hepatitis virus (MHV) leader RNA. We have purified this protein and determined by partial peptide sequencing that it is polypyrimidine tract-binding protein (PTB) (also known as heterogeneous nuclear ribonucleoprotein [hnRNP] I), a nuclear protein which shuttles between the nucleus and cytoplasm. PTB plays a role in the regulation of alternative splicing of pre-mRNAs in normal cells and translation of several viruses. By UV cross-linking and immunoprecipitation studies using cellular extracts and a recombinant PTB, we have established that PTB binds to the MHV plus-strand leader RNA specifically. Deletion analyses of the leader RNA mapped the PTB-binding site to the UCUAA pentanucleotide repeats. Using a defective-interfering RNA reporter system, we have further shown that the PTB-binding site in the leader RNA is critical for MHV RNA synthesis. This and our previous study (H.-P. Li, X. Zhang, R. Duncan, L. Comai, and M. M. C. Lai, Proc. Natl. Acad. Sci. USA 94:9544–9549, 1997) combined thus show that two cellular hnRNPs, PTB and hnRNP A1, bind to the transcription-regulatory sequences of MHV RNA and may participate in its transcription. PMID:9847386

  16. Self-Assembly of Janus Oligomers into Onion-like Vesicles with Layer-by-Layer Water Discharging Capability: A Minimalist Model.

    PubMed

    Arai, Noriyoshi; Yasuoka, Kenji; Zeng, Xiao Cheng

    2016-08-23

    A vesicle in a cell is an enclosed structure in which the interior fluid is encompassed by a lipid bilayer. Synthetic vesicles are known as the liposomes. Liposomes with a single phospholipid bilayer are called unilamellar liposomes; otherwise, they are called multilamellar liposomes or onion-like liposomes (vesicles). One prototype synthetic onion-like vesicle, namely, onion-like dendrimersomes, have been recently produced via the self-assembly of amphiphilic Janus dendrimers (Proc. Natl. Acad. Sci. U.S.A. 2016, 113, 1162). Herein, we show computer simulation evidence of another type of onion-like vesicle, namely, onion-like oligomersomes, via the self-assembly of amphiphilic Janus oligomers in water. Specifically, we investigate the minimum-sized oligomers (or minimalist model) that can give rise to the onion-like oligomersomes as well as the composition-dependent phase diagrams. Insights into the formation condition and formation process of the onion-like oligomersomes are obtained. We demonstrate that the discharge of the in-vesicle water is through the remarkable "peeling-one-onion-layer-at-a-time" fashion, a feature that can be utilized for a clinical dosing regimen. The ability to control the formation of onion-like oligomersomes by design can be exploited for applications in drug and gene delivery.

  17. From crystal and NMR structures, footprints and cryo-electron-micrographs to large and soft structures: nanoscale modeling of the nucleosomal stem

    PubMed Central

    Meyer, Sam; Becker, Nils B.; Syed, Sajad Hussain; Goutte-Gattat, Damien; Shukla, Manu Shubhdarshan; Hayes, Jeffrey J.; Angelov, Dimitar; Bednar, Jan; Dimitrov, Stefan; Everaers, Ralf

    2011-01-01

    The interaction of histone H1 with linker DNA results in the formation of the nucleosomal stem structure, with considerable influence on chromatin organization. In a recent paper [Syed,S.H., Goutte-Gattat,D., Becker,N., Meyer,S., Shukla,M.S., Hayes,J.J., Everaers,R., Angelov,D., Bednar,J. and Dimitrov,S. (2010) Single-base resolution mapping of H1-nucleosome interactions and 3D organization of the nucleosome. Proc. Natl Acad. Sci. USA, 107, 9620–9625], we published results of biochemical footprinting and cryo-electron-micrographs of reconstituted mono-, di- and tri-nucleosomes, for H1 variants with different lengths of the cationic C-terminus. Here, we present a detailed account of the analysis of the experimental data and we include thermal fluctuations into our nano-scale model of the stem structure. By combining (i) crystal and NMR structures of the nucleosome core particle and H1, (ii) the known nano-scale structure and elasticity of DNA, (iii) footprinting information on the location of protected sites on the DNA backbone and (iv) cryo-electron micrographs of reconstituted tri-nucleosomes, we arrive at a description of a polymorphic, hierarchically organized stem with a typical length of 20 ± 2 base pairs. A comparison to linker conformations inferred for poly-601 fibers with different linker lengths suggests, that intra-stem interactions stabilize and facilitate the formation of dense chromatin fibers. PMID:21835779

  18. Higher cytotoxicity of divalent antibody-toxins than monovalent antibody-toxins

    SciTech Connect

    Won, JaeSeon; Nam, PilWon; Lee, YongChan; Choe, MuHyeon

    2009-04-24

    Recombinant antibody-toxins are constructed via the fusion of a 'carcinoma-specific' antibody fragment to a toxin. Due to the high affinity and high selectivity of the antibody fragments, antibody-toxins can bind to surface antigens on cancer cells and kill them without harming normal cells [L.H. Pai, J.K. Batra, D.J. FitzGerald, M.C. Willingham, I. Pastan, Anti-tumor activities of immunotoxins made of monoclonal antibody B3 and various forms of Pseudomonas exotoxin, Proc. Natl. Acad. Sci. USA 88 (1991) 3358-3362]. In this study, we constructed the antibody-toxin, Fab-SWn-PE38, with SWn (n = 3, 6, 9) sequences containing n-time repeated (G{sub 4}S) between the Fab fragment and PE38 (38 kDa truncated form of Pseudomonas exotoxin A). The SWn sequence also harbored one cysteine residue that could form a disulfide bridge between two Fab-SWn-PE38 monomers. We assessed the cytotoxicity of the monovalent (Fab-SWn-PE38), and divalent ([Fab-SWn-PE38]{sub 2}) antibody-toxins. The cytotoxicity of the dimer against the CRL1739 cell line was approximately 18.8-fold higher than that of the monomer on the ng/ml scale, which was approximately 37.6-fold higher on the pM scale. These results strongly indicate that divalency provides higher cytotoxicity for an antibody-toxin.

  19. Caterpillars did not evolve from onychophorans by hybridogenesis.

    PubMed

    Hart, Michael W; Grosberg, Richard K

    2009-11-24

    The evolution and loss of distinctive larval forms in animal life cycles have produced complex patterns of similarity and difference among life-history stages and major animal lineages. One example of this similarity is the morphological forms of Onychophora (velvet worms) and the caterpillar-like larvae of some insects. Williamson [(2009) Proc Natl Acad Sci USA 106:15786-15790] has made the astonishing and unfounded claim that the ancestors of the velvet worms directly gave rise to insect caterpillars via hybridization and that evidence of this ancient "larval transfer" could be found in comparisons among the genomes of extant onychophorans, insects with larvae, and insects without larvae. Williamson has made a series of predictions arising from his hypothesis and urged genomicists to test them. Here, we use data already in the literature to show these predictions to be false. Hybridogenesis between distantly related animals does not explain patterns of morphological and life-history evolution in general, and the genes and genomes of animals provide strong evidence against hybridization or larval transfer between a velvet worm and an insect in particular.

  20. Psychophysical tuning curves at very high frequencies

    NASA Astrophysics Data System (ADS)

    Yasin, Ifat; Plack, Christopher J.

    2005-10-01

    For most normal-hearing listeners, absolute thresholds increase rapidly above about 16 kHz. One hypothesis is that the high-frequency limit of the hearing-threshold curve is imposed by the transmission characteristics of the middle ear, which attenuates the sound input [Masterton et al., J. Acoust. Soc. Am. 45, 966-985 (1969)]. An alternative hypothesis is that the high-frequency limit of hearing is imposed by the tonotopicity of the cochlea [Ruggero and Temchin, Proc. Nat. Acad. Sci. U.S.A. 99, 13206-13210 (2002)]. The aim of this study was to test these hypotheses. Forward-masked psychophysical tuning curves (PTCs) were derived for signal frequencies of 12-17.5 kHz. For the highest signal frequencies, the high-frequency slopes of some PTCs were steeper than the slope of the hearing-threshold curve. The results also show that the human auditory system displays frequency selectivity for characteristic frequencies (CFs) as high as 17 kHz, above the frequency at which absolute thresholds begin to increase rapidly. The findings suggest that, for CFs up to 17 kHz, the high-frequency limitation in humans is imposed in part by the middle-ear attenuation, and not by the tonotopicity of the cochlea.

  1. Acid-induced folding of yeast alcohol dehydrogenase under low pH conditions.

    PubMed

    Le, W P; Yan, S X; Zhang, Y X; Zhou, H M

    1996-04-01

    Under conditions of low pH, the conformational states of holo-YADH and apo-YADH were examined by protein intrinsic fluorescence, ANS fluorescence, and far-UV CD measurements. The results obtained show that a low ionic strength, with the addition of HCl, the holo- and apo- YADH denatured gradually to reach the ultimate unfolded conformation in the vicinity of pH 2.0 and 2.5, respectively. With the decrease of pH from 7.0 to 2.0, the fluorescence emission decreased markedly, with its emission maximum red-shifting from 335 to 355 nm, indicating complete exposure of the buried tryptophan residues to the solvent. The far-UV CD spectra show the loss of the arrayed secondary structure, though the acid-denatured enzyme still maintained a partially arrayed secondary structure. A further decrease in pH by increasing the concentration of HClO4 induced a cooperative folding of the denatured enzyme to a compact conformation with the properties of a molten globule, described previously by Goto et al. [Proc. Natl. Acad. Sci. USA 87, 573-577 (1990)]. More extensive studies showed that although apo-YADH and holo-YADH exhibited similar behavior, the folding cooperative ability of apo-YADH was lower than that of the holo-enzyme. From the above results, it is suggested that the zinc ion plays an important role in the proper folding of YADH and in stabilizing its native conformation.

  2. [Denis Ballière (1729-1800)].

    PubMed

    Trépardoux, Francis

    2002-01-01

    Born in Paris in 1729, Ballière got his graduation from the University of Sorbonne as bachelor of arts in 1746. His uncle Charles Delaisement practised as apothecary in Rouen and Ballière obtained there his mastership in 1756. Concomitantly, he composed the poetry and music of several opéras-comiques in the style of pastorales, which were performed with success in Rouen and Paris theaters. He was a fine writer and a real erudite. As well, his capacity in mathematics lead him to set up a theory applicated to both acoustic and music. In 1764 was published his Théorie de la musique in which he analysed the works of Descartes, Sauveur, Wallis, Tartini, Rameau, d'Alembert and Diderot. Rousseau greeted this work with consideration. When his uncle died in 1768, he fully engaged in the pharmaceutical profession. Since 1754, he had been a member of the Académie de Rouen, in which he was scientific secretary in 1769 and president in 1784, publishing different works among them its Essai sur les problèmes de situation - regarding the probability calculus - can be mentioned. In 1779, he translated into French John Ellis's book on Mangostan. He died in Rouen in 1800. PMID:12380583

  3. Protective effects of glycyrrhizic acid from edible botanical glycyrrhiza glabra against non-alcoholic steatohepatitis in mice.

    PubMed

    Wang, Changyuan; Duan, Xingping; Sun, Xue; Liu, Zhihao; Sun, Pengyuan; Yang, Xiaobo; Sun, Huijun; Liu, Kexin; Meng, Qiang

    2016-09-14

    Non-alcoholic steatohepatitis (NASH) is a syndrome with simultaneous severe hepatic steatosis, lobular inflammation and pericelluar fibrosis. The purpose of the present study is to investigate the protective effect of glycyrrhizic acid (GA), a natural triterpene glycoside from edible botanical glycyrrhiza glabra, on NASH induced by a methionine and choline-deficient (MCD) diet in mice, and further to elucidate the mechanisms of GA protection. Serum ALT and AST assay and H&E staining were used to identify the amelioration of the liver histopathological changes. Serum and hepatic lipid assay and Oil Red O staining were used to measure lipid accumulation. Hepatic inflammatory and fibrosis gene determination, as well as Mason Trichrome and Sirius Red staining were used to determine the reduction of hepatic inflammation and pericelluar fibrosis. Quantitative real-time PCR and Western blot assays were used to elucidate the mechanisms underlying GA protection. The results indicated that GA treatment reduced hepatic lipogenesis through a decrease in hepatic levels of SREBP-1c, FAS, ACC1 and SCD1, and increased lipid metabolism through an induction of PPARα, CPT1α, ACADS and LPL. GA also reduced hepatic inflammation via a decrease in the expression of the hepatic inflammatory genes MCP-1 and VCAM-1. In addition, GA reduced liver fibrosis through limiting HSC activation and collagen deposition. In conclusion, GA produces a markedly protective effect against NASH induced by a methionine and choline-deficient (MCD) diet in mice. PMID:27487733

  4. Excitonic connectivity between photosystem II units: what is it, and how to measure it?

    PubMed

    Stirbet, Alexandrina

    2013-10-01

    In photosynthetic organisms, light energy is absorbed by a complex network of chromophores embedded in light-harvesting antenna complexes. In photosystem II (PSII), the excitation energy from the antenna is transferred very efficiently to an active reaction center (RC) (i.e., with oxidized primary quinone acceptor Q(A)), where the photochemistry begins, leading to O2 evolution, and reduction of plastoquinones. A very small part of the excitation energy is dissipated as fluorescence and heat. Measurements on chlorophyll (Chl) fluorescence and oxygen have shown that a nonlinear (hyperbolic) relationship exists between the fluorescence yield (Φ(F)) (or the oxygen emission yield, (Φ(O2)) and the fraction of closed PSII RCs (i.e., with reduced Q(A)). This nonlinearity is assumed to be related to the transfer of the excitation energy from a closed PSII RC to an open (active) PSII RC, a process called PSII excitonic connectivity by Joliot and Joliot (CR Acad Sci Paris 258: 4622-4625, 1964). Different theoretical approaches of the PSII excitonic connectivity, and experimental methods used to measure it, are discussed in this review. In addition, we present alternative explanations of the observed sigmoidicity of the fluorescence induction and oxygen evolution curves. PMID:23794168

  5. Transition to farming more likely for small, conservative groups with property rights, but increased productivity is not essential.

    PubMed

    Gallagher, Elizabeth M; Shennan, Stephen J; Thomas, Mark G

    2015-11-17

    Theories for the origins of agriculture are still debated, with a range of different explanations offered. Computational models can be used to test these theories and explore new hypotheses; Bowles and Choi [Bowles S, Choi J-K (2013) Proc Natl Acad Sci USA 110(22):8830-8835] have developed one such model. Their model shows the coevolution of farming and farming-friendly property rights, and by including climate variability, replicates the timings for the emergence of these events seen in the archaeological record. Because the processes modeled occurred a long time ago, it can be difficult to justify exact parameter values; hence, we propose a fitting to idealized outcomes (FIO) method to explore the model's parameter space in more detail. We have replicated the model of Bowles and Choi, and used the FIO method to identify complexities and interactions of the model previously unidentified. Our results indicate that the key parameters for the emergence of farming are group structuring, group size, conservatism, and farming-friendly property rights (lending further support to Bowles and Choi's original proposal). We also find that although advantageous, it is not essential that farming productivity be greater than foraging productivity for farming to emerge. In addition, we highlight how model behaviors can be missed when gauging parameter sensitivity via a fix-all-but-one variation approach.

  6. Thermal history of the Pan-African/Brasiliano Borborema Province of northeast Brazil deduced from 40Ar/ 39Ar analysis

    NASA Astrophysics Data System (ADS)

    Corsini, M.; de Figueiredo, L. Lambert; Caby, R.; Féraud, G.; Ruffet, G.; Vauchez, A.

    1998-02-01

    Detailed step heating 40Ar/ 39Ar analyses were performed on different minerals from magmatic and metamorphic rocks of the Borborema Province. This region, located in northeast Brazil, belongs to the Pan-African/Brasiliano belt which is about 1000 km wide and 600 km long. Twenty-six single grains of amphibole, muscovite and biotite were extracted from eighteen samples selected in an area of about 17,500 km 2 (250 km by 70 km) in the Patos region. This region has been affected by a continental-scale shear zone system. Well-defined 40Ar/ 39Ar plateau ages and an U sbnd Pb analysis on zircon [Leterrier, J., Jardim de Sà, E.F, Bertrand, J.M. and Pin, C., 1994. Ages U sbnd Pb sur zircon de granitoïdes brasilianos de la ceinture du Serido (Province Borborema, NE brésil). C.R. Acad. Sci., Paris, 318: 1505-1511] allow the definition of a homogeneous and unusual slow cooling history (3-4°C/Ma) and suggest a rather slow uplift rate between 580 and 500 Ma, followed by a fast cooling of the whole studied area around 500 Ma. Rapid cooling is suggested by concordant plateau ages on muscovite and biotite. The existence of such an event at the end of the belt history is in agreement with data obtained on other major belts such as the Alpine-Himalayan system or the Hercynian belt.

  7. Role of interference in the photosynthetic heat engine

    NASA Astrophysics Data System (ADS)

    Xu, Y. Y.; Liu, J.

    2014-11-01

    The observation of quantum coherence in pigment-protein complexes has attracted considerable interest. One such endeavor entails applying a quantum heat engine to model the photosynthetic reaction center, but the definition of work used is inconsistent with that defined in quantum thermodynamics. Using the definition of work proposed in Weimer et al. [Europhys. Lett. 83, 30008 (2008), 10.1209/0295-5075/83/30008], we investigated two proposals for enhancing the performance of the photosynthetic reaction center. In proposal A, which is similar to that in Dorfman et al. [Proc. Natl. Acad. Sci. USA 110, 2746 (2013), 10.1073/pnas.1212666110], we found that the power and current-voltage characteristic of the heat engine can be increased by Fano interference but the efficiency cannot. In proposal B, which is similar to that in Creatore et al. [Phys. Rev. Lett. 111, 253601 (2013), 10.1103/PhysRevLett.111.253601], we found that the mechanism of strengthening the performance of the heat engine is invalid; i.e., the dipole-dipole interaction between two electron donors could not increase the power, efficiency, or current-voltage characteristic.

  8. Novel treatment of a failed quadriceps tendon repair in a diabetic patient using a patella-quadriceps tendon allograft.

    PubMed

    Druskin, Sasha C; Rodeo, Scott A

    2013-07-01

    Recurrent quadriceps tendon rupture is a debilitating condition that may be challenging to treat, especially in the presence of systemic disease such as diabetes mellitus (Bedi et al., J Shoulder Elbow Surg 19:978-988, 2010; Chbnou and Frenette, Am J Physiol Regul Integr Comp Physiol 5:R952-R957, 2004; Chen et al., J Shoulder Elbow Surg 5:416-421, 2003). Many surgical treatment protocols have been proposed (Azar, in Canale and Beatty, eds., Campbell's Operative Orthopedics, Mosby/Elsevier, Philadelphia, PA, 2008; Ilan et al., J Am Acad Orthop Surg 3:192-200, 2003; Rodeo and Izawa, in Garrett et al., eds., Principles and Practice of Orthopedic Sports Medicine, Lippincott Williams & Wilkins, Philadelphia, PA, 2000). We report the case of a diabetic male with multiple treatment failures. He ultimately sustained a good outcome following treatment with a novel surgical technique that utilized a patella quadriceps tendon allograft. Tendon allograft-to-native bone healing had previously failed in this patient, so we used a bone-tendon construct allograft to provide an allograft bone-to-native bone healing site. Now, 13 months postoperative, the patient has increased strength, minimal pain, 20 ° of extensor lag and 130 ° of flexion.

  9. Detecting Repetitions and Periodicities in Proteins by Tiling the Structural Space

    PubMed Central

    2013-01-01

    The notion of energy landscapes provides conceptual tools for understanding the complexities of protein folding and function. Energy landscape theory indicates that it is much easier to find sequences that satisfy the “Principle of Minimal Frustration” when the folded structure is symmetric (Wolynes, P. G. Symmetry and the Energy Landscapes of Biomolecules. Proc. Natl. Acad. Sci. U.S.A.1996, 93, 14249–14255). Similarly, repeats and structural mosaics may be fundamentally related to landscapes with multiple embedded funnels. Here we present analytical tools to detect and compare structural repetitions in protein molecules. By an exhaustive analysis of the distribution of structural repeats using a robust metric, we define those portions of a protein molecule that best describe the overall structure as a tessellation of basic units. The patterns produced by such tessellations provide intuitive representations of the repeating regions and their association toward higher order arrangements. We find that some protein architectures can be described as nearly periodic, while in others clear separations between repetitions exist. Since the method is independent of amino acid sequence information, we can identify structural units that can be encoded by a variety of distinct amino acid sequences. PMID:23758291

  10. Multiple critical points and liquid liquid equilibria from the van der Waals like equations of state

    NASA Astrophysics Data System (ADS)

    Artemenko, Sergey; Lozovsky, Taras; Mazur, Victor

    2008-06-01

    The principal aim of this work is a comprehensive analysis of the phase diagram of water via the van der Waals like equations of state (EoSs) which are considered as superpositions of repulsive and attractive forces. We test more extensively the modified van der Waals EoS (MVDW) proposed by Skibinski et al (2004 Phys. Rev. E 69 061206) and refine this model by introducing instead of the classical van der Waals repulsive term a very accurate hard sphere EoS over the entire stable and metastable regions (Liu 2006 Preprint cond-mat/0605392). It was detected that the simplest form of MVDW EoS displays a complex phase behavior, including three critical points, and identifies four fluid phases (gas, low density liquid (LDL), high density liquid (HDL), and very high density liquid (VHDL)). Moreover the experimentally observed (Mallamace et al 2007 Proc. Natl Acad. Sci. USA 104 18387) anomalous behavior of the density of water in the deeply supercooled region (a density minimum) is reproduced by the MWDW EoS. An improvement of the repulsive part does not change the topological picture of the phase behavior of water in the wide range of thermodynamic variables. The new parameters set for second and third critical points are recognized by thorough analysis of experimental data for the loci of thermodynamic response function extrema.

  11. Calcitonin: regional distribution of the hormone and its binding sites in the human brain and pituitary.

    PubMed Central

    Fischer, J A; Tobler, P H; Kaufmann, M; Born, W; Henke, H; Cooper, P E; Sagar, S M; Martin, J B

    1981-01-01

    Immunoreactive calcitonin (CT), indistinguishable from human CT-(1-32) and its sulfoxide, has been identified in extracts of the hypothalamus, the pituitary, and the thyroid obtained from human subjects at autopsy. DCT concentrations were highest in a region encompassing the posterior hypothalamus, the median eminence, and the pituitary; intermediate in the substantia nigra, the anterior hypothalamus, the globus pallidus, and the inferior colliculus; and low in the caudate nucleus, the hippocampus, the amygdala, and the cerebral and cerebellar cortices. Specific CT binding measured with 125I-labeled salmon CT was highest in homogenates of the posterior hypothalamus and the median eminence, shown to contain the highest concentrations of endogenous CT in the brain; CT binding was less than 12% of hypothalamic binding in all of the other regions of the brain examined and was negligible in the pituitary. Half-maximal binding was achieved with 0.1 nM nonradioactive salmon CT-(1-32), and the binding was directed to structural or conformational sites, or both, in the COOH-terminal half of salmon CT. The rank order of the inhibition of the binding by CT from different species and analogues of the human hormone was the same as in receptors on a human lymphoid cell line (Moran, J., Hunziker, W. & Fischer, J. A. (1978) Proc. Natl. Acad. Sci. USA 75, 3984-3988). The functional role of CT and of its binding sites in the brain remains to be elucidated. PMID:6950419

  12. Transmission-blocking activity of a chitinase inhibitor and activation of malarial parasite chitinase by mosquito protease.

    PubMed Central

    Shahabuddin, M; Toyoshima, T; Aikawa, M; Kaslow, D C

    1993-01-01

    During development in the mosquito midgut, malarial parasites must traverse a chitin-containing peritrophic matrix (PM) that forms around the food bolus. Previously Huber et al. [Huber, M., Cabib, E. & Miller, L. H. (1991) Proc. Natl. Acad. Sci. USA 88, 2807-2810] reported that the parasite secretes a protein with chitinase activity, and they suggested that parasite chitinase (EC 3.2.1.14) plays an important role in the parasite's egress from the blood meal. We found that allosamidin, a specific inhibitor of chitinase, completely blocked oocyst development in vivo and thus blocked malaria parasite transmission. Addition of exogenous chitinase to the blood meal prevented the PM from forming and reversed the transmission-blocking activity of allosamidin. Using exogenous chitinase, we also found that the PM does not limit the number of parasites that develop into oocysts, suggesting that the parasite produces sufficient quantities of chitinase to penetrate this potential barrier. In addition, we found that treatment of parasite chitinase with a diisopropyl fluorophosphate-sensitive trypsinlike protease from the mosquito midgut or endoproteinase Lys-C increased its enzymatic activity. These results suggest that malaria parasite has evolved an intricate mechanism to adapt to the PM and the protease-rich environment of the mosquito midgut. Images Fig. 2 PMID:8483942

  13. [Clinical features of Zika virus].

    PubMed

    Cabrera-Gaytán, David Alejandro; Galván-Hernández, Stephanie Anaid

    2016-01-01

    Introducción: el virus Zika se ha introducido al país y amenaza en propagarse, por lo que el personal de salud se enfrentará a la necesidad de identificar la enfermedad dada una definición operacional de caso; en esta revisión se describen las manifestaciones clínicas de casos probables de Zika de los últimos cinco años. Métodos: se realizó una búsqueda en Google Académico y PubMed con la palabra “Zika”. Se conformó una base de datos, se obtuvieron frecuencias simples y se calcularon los límites para proporciones con un alfa del 0.05 por medio de prueba de Wilson. Resultados: se conjuntaron 109 casos probables de fiebre por Zika, las manifestaciones clínicas fueron heterogéneas, con predominio de afectación a nivel musculoesquelético, dermatológico y sistémico. Conclusiones: es necesario continuar la documentación de las manifestaciones clínicas del virus Zika, que se logrará mediante el fortalecimiento de la vigilancia epidemiológica.

  14. Poly(beta-hydroxybutyrate) production in oilseed leukoplasts of brassica napus

    PubMed

    Houmiel; Slater; Broyles; Casagrande; Colburn; Gonzalez; Mitsky; Reiser; Shah; Taylor; Tran; Valentin; Gruys

    1999-10-01

    Polyhydroxyalkanoates (PHAs) comprise a class of biodegradable polymers which offer an environmentally sustainable alternative to petroleum-based plastics. Production of PHAs in plants is attractive since current fermentation technology is prohibitively expensive. The PHA homopolymer poly(beta-hydroxybutyrate) (PHB) has previously been produced in leaves of Arabidopsis thaliana (Nawrath et al., 1994, Proc Natl Acad Sci USA 91: 12760-12764). However, Brassica napus oilseed may provide a better system for PHB production because acetyl-CoA, the substrate required in the first step of PHB biosynthesis, is prevalent during fatty acid biosynthesis. Three enzymatic activities are needed to synthesize PHB: a beta-ketothiolase, an acetoacetyl-CoA reductase and a PHB synthase. Genes from the bacterium Ralstonia eutropha encoding these enzymes were independently engineered behind the seed-specific Lesquerella fendleri oleate 12-hydroxylase promoter in a modular fashion. The gene cassettes were sequentially transferred into a single, multi-gene vector which was used to transform B. napus. Poly(beta-hydroxybutyrate) accumulated in leukoplasts to levels as high as 7.7% fresh seed weight of mature seeds. Electron-microscopy analyses indicated that leukoplasts from these plants were distorted, yet intact, and appeared to expand in response to polymer accumulation.

  15. Structural stability study of protein monolayers in air

    NASA Astrophysics Data System (ADS)

    Pompa, P. P.; Biasco, A.; Cingolani, R.; Rinaldi, R.; Verbeet, M. Ph.; Canters, G. W.

    2004-03-01

    The assessment of the folding and of the structural stability of a protein in air, upon immobilization in the solid state, represents a critical point from both a fundamental point of view and for the development of solid state nanobioelectronics. The recent demonstrations by Rinaldi et al. [R. Rinaldi et al., Adv. Mater. 14, 1453 (2002); Appl. Phys. Lett. 82, 472 (2003); Ann. (N.Y.) Acad. Sci. 1006, 187 (2003)] of protein-based solid state devices and transistors working in air have raised an intriguing question about the behavior of a biomolecule under nonphysiological conditions. The operation principle of the realized devices is based on the physiological electron transfer function of the metalloprotein azurin. This means that azurin should retain its shape and functionality also in the solid state when utilized in air and at room temperature. In this Brief Report, we prove this claim by analyzing the conformational state of the azurin monolayers developed for such devices by means of intrinsic fluorescence spectroscopy. We show that the immobilization of azurins in the solid state under nonliquid conditions, by means of a specific chemisorption process, does not necessarily lead to protein denaturation. This result is of great importance because it opens up interesting perspectives for the development of solid state hybrid nanodevices for electronic applications requiring nonliquid environments.

  16. Analytical solutions to the backward Kolmogorov PDE via an adiabatic approximation to the Schrödinger PDE

    NASA Astrophysics Data System (ADS)

    Haven, Emmanuel

    2005-11-01

    Analytical solutions to the backward Kolmogorov PDE are very dependent on the functional form of b(y,t) and a(y,t). We suggest one solution technique for obtaining analytical solutions via the use of an adiabatic approximation to the Schrödinger PDE. This approximation takes the specific form of a so-called WKB (W D Wentzel [G. Wentzel, Eine Verallgemeinerung der Quantenbedingungen für die Zwecke der Wellenmechanik, Z. Phys. 38 (1926) 518-529], K D Kramers [H. Kramers, Wellenmechanik und halbzahlige Quantisierung, Z. Phys. 39 (1926) 828-840], B D Brillouin [L. Brillouin, La mécanique ondulatoire de Schrödinger: une méthode générale de résolution par approximations successives, C. R. Acad. Sci. 183 (1926) 24-26]) approximation. We provide for two examples, in financial option pricing, where we show how the proposed approximation could be of use.

  17. Ab initio molecular dynamics studies on HIV-1 reverse transcriptase triphosphate binding site: implications for nucleoside-analog drug resistance.

    PubMed

    Alber, F; Carloni, P

    2000-12-01

    Quantum-chemical methods are used to shed light on the functional role of residues involved in the resistance of HIV-1 reverse transcriptase against nucleoside-analog drugs. Ab initio molecular dynamics simulations are carried out for models representing the adduct between the triphosphate substrate and the nucleoside binding site. The triphosphate is considered either deprotonated or protonated at the gamma-position. Although the protonated form already experiences large rearrangements in the ps time scale, the fully deprotonated state exhibits a previously unrecognized low-barrier hydrogen bond between Lys65 and gamma-phosphate. Absence of this interaction in Lys65-->Arg HIV-1 RT might play a prominent role in the resistance of this mutant for nucleoside analogs (Gu Z et al., 1994b, Antimicrob Agents Chemother 38:275-281; Zhang D et al., 1994, Antimicrob Agents Chemother 38:282-287). Water molecules present in the active site, not detected in the X-ray structure, form a complex H-bond network. Among these waters, one may be crucial for substrate recognition as it bridges Gln151 and Arg72 with the beta-phosphate. Absence of this stabilizing interaction in Gln151-->Met HIV-1 RT mutant may be a key factor for the known drug resistance of this mutant toward dideoxy-type drugs and AZT (Shirasaka T et al., 1995, Proc Natl Acad Sci USA 92:2398-2402: Iversen AK et al., 1996, J Virol 70:1086-1090).

  18. Resilience and controllability of dynamic collective behaviors.

    PubMed

    Komareji, Mohammad; Bouffanais, Roland

    2013-01-01

    The network paradigm is used to gain insight into the structural root causes of the resilience of consensus in dynamic collective behaviors, and to analyze the controllability of the swarm dynamics. Here we devise the dynamic signaling network which is the information transfer channel underpinning the swarm dynamics of the directed interagent connectivity based on a topological neighborhood of interactions. The study of the connectedness of the swarm signaling network reveals the profound relationship between group size and number of interacting neighbors, which is found to be in good agreement with field observations on flock of starlings [Ballerini et al. (2008) Proc. Natl. Acad. Sci. USA, 105: 1232]. Using a dynamical model, we generate dynamic collective behaviors enabling us to uncover that the swarm signaling network is a homogeneous clustered small-world network, thus facilitating emergent outcomes if connectedness is maintained. Resilience of the emergent consensus is tested by introducing exogenous environmental noise, which ultimately stresses how deeply intertwined are the swarm dynamics in the physical and network spaces. The availability of the signaling network allows us to analytically establish for the first time the number of driver agents necessary to fully control the swarm dynamics. PMID:24358209

  19. Group selection and kin selection: two concepts but one process.

    PubMed

    Lehmann, Laurent; Keller, Laurent; West, Stuart; Roze, Denis

    2007-04-17

    In a recent paper, Traulsen and Nowak use a multilevel selection model to show that cooperation can be favored by group selection in finite populations [Traulsen A, Nowak M (2006) Proc Natl Acad Sci USA 103:10952-10955]. The authors challenge the view that kin selection may be an appropriate interpretation of their results and state that group selection is a distinctive process "that permeates evolutionary processes from the emergence of the first cells to eusociality and the economics of nations." In this paper, we start by addressing Traulsen and Nowak's challenge and demonstrate that all their results can be obtained by an application of kin selection theory. We then extend Traulsen and Nowak's model to life history conditions that have been previously studied. This allows us to highlight the differences and similarities between Traulsen and Nowak's model and typical kin selection models and also to broaden the scope of their results. Our retrospective analyses of Traulsen and Nowak's model illustrate that it is possible to convert group selection models to kin selection models without disturbing the mathematics describing the net effect of selection on cooperation. PMID:17416674

  20. [Infectious complications in patients with iatrogenic diseases of the trachea and esophagus].

    PubMed

    Parshin, V D; Bogomolova, N S; Vishnevskaia, G A; Bol'shakov, L V; Oreshkina, T D; Kuznetsova, S M; Chernyĭ, S S

    2010-01-01

    Methods for microbiological monitoring could analyze the microflora isolated in 372 patients with iatrogenic diseases of the trachea and esophagus, who were treated at the Department for Surgery of the Lung and Mediastinum, Acad. B. V. Petrovsky Russian Research Center of Surgery, Russian Academy of Medical Sciences, in 2003 to 2009. Major groups of microorganisms colonizing the tracheobronchial tree in patients who had undergone long-term resuscitation, injuries, surgery, etc. and in those who had admitted to the department from other clinics are identified. The main clinically significant microorganisms isolated during the pathological process in this area were Staphylococcus epidermadis (3.9-13.3%), St. aureus (12.4-21.1%), Pseudomonas eruginosa (9.2-17.5%), and Candida fungi (7.8-12.2%). This indicates the greater importance of the fungal microflora and its representatives' resistance to the most commonly used drugs. Rational antibacterial therapy regimens are proposed in relation to the type of microorganisms colonizing the tracheobronchial tree.

  1. Prostaglandin Endoperoxides. A New Concept Concerning the Mode of Action and Release of Prostaglandins*

    PubMed Central

    Hamberg, Mats; Svensson, Jan; Samuelsson, Bengt

    1974-01-01

    Methods were developed for quantitative determination of the three major metabolites of arachidonic acid in human platelets, i.e., 12L-hydroxy-5,8,10,14-eicosatetraenoic acid (HETE), 12L-hydroxy-5,8,10-heptadecatrienoic acid (HHT) and 8-(1-hydroxy-3-oxopropyl)-9,12L-dihydroxy-5,10-heptadecadienoic acid (PHD). Aggregation of washed platelets by thrombin was accompanied by release of 1163-2175 ng/ml of HETE, 1129-2430 ng/ml of HHT, and 998-2299 ng/ml of PHD. The amount of PGG2 (prostaglandin G2) produced as calculated from the sum of the amounts of its metabolites (HHT and PHD) was 2477-5480 ng/ml. In contrast, the amounts of PGE2 (prostaglandin E2) and PGF2α (prostaglandin F2α) released were approximately two orders of magnitude lower. In this system, the prostaglandins thus exert their biological action through the endoperoxides, which are almost exclusively metabolized to nonprostanoate structures and only to a small extent to the classical prostaglandins. Platelets from subjects given aspirin produced less than 5% of the above mentioned amounts of HHT and PHD, whereas the production of HETE was stimulated about 3-fold. This provides additional evidence for our earlier proposal [Hamberg, M., Svensson, J., Wakabayashi, T. & Samuelsson, B. (1974) Proc. Nat. Acad. Sci. USA 71, 345-349] that the anti-aggregating effect of aspirin is through inhibition of PGG2 formation. PMID:4530264

  2. Bertrand's paradox: a physical way out along the lines of Buffon's needle throwing experiment

    NASA Astrophysics Data System (ADS)

    Di Porto, P.; Crosignani, B.; Ciattoni, A.; Liu, H. C.

    2011-05-01

    Bertrand's paradox (Bertrand 1889 Calcul des Probabilités (Paris: Gauthier-Villars)) can be considered as a cautionary memento, to practitioners and students of probability calculus alike, of the possible ambiguous meaning of the term 'at random' when the sample space of events is continuous. It deals with the existence of different possible answers to the following question: what is the probability that a chord, drawn at random in a circle of radius R, is longer than the side R \\sqrt{3} of an inscribed equilateral triangle? Physics can help to remove the ambiguity by identifying an actual experiment, whose outcome is obviously unique and prescribes the physical variables to which the term 'random' can be correctly applied. In this paper, after briefly describing Bertrand's paradox, we associate it with an experiment, which is basically a variation of the famous Buffon's needle experiment (Buffon 1733 Histoire de l'Acad. Roy. des. Sciences pp 43-5 Buffon 1777 Histoire naturelle, générale et particulière Supplément 4 46) for estimating the value of π. Its outcome is compared with the analytic predictions of probability calculus, that is with the probability distribution of variables whose uniform distribution can be considered a sound implementation of complete randomness.

  3. Cu(II) coordination structure determinants of the fibrillization switch in Abeta peptides

    NASA Astrophysics Data System (ADS)

    Hernandez-Guzman, Jessica; Sun, Li; Mehta, Anil; Lynn, David; Warncke, Kurt

    2010-03-01

    Alzheimer's Disease (AD) is associated with the aggregation and fibrillization of the beta-amyloid protein (Abeta). The coordination of Cu(II) by peptide histidine imidazole sidechains is proposed to play an important role in determining the fibrillization ``switch'' [1]. We have developed techniques of powder X-band electron spin echo envelope modulation (ESEEM) spectroscopy to determine the 3D molecular structure of the Cu(II)-histidine imidazole coordination in cryotrapped soluble and fibrillar forms of Abeta peptides, in order to gain insight into the factors that govern fibrillization. We use hybrid optimization-based OPTESIM [2] simulation of the double quantum harmonic feature to determine the mutual orientation of the imidazole rings in Cu(II)--bis-imidazole complexes and in Abeta(13-21) peptides. The Cu(II) coordination mode and assembly constraints in fibrils are revealed. [1] Dong , J., et al., Proc. Natl. Acad. Sci., 2007, 104, 13313. [2] Sun, L., et al., J. Magn. Reson. 2009, 200, 21.

  4. 3'-O-(5-fluoro-2,4-dinitrophenyl)ADP ether and ATP ether. Affinity reagents for labeling ATPases.

    PubMed

    Chuan, H; Wang, J H

    1988-09-15

    The affinity reagents 3'-O-(5-fluoro-2,4-dinitrophenyl)ADP ether (FDNP-ADP) and 3'-O-(5-fluoro-2,4-dinitrophenyl)ATP ether (FDNP-ATP) were synthesized and characterized. FDNP[14C]ADP was found to label the active site of mitochondrial F1-ATPase slowly at room temperature but with high specificity. F1 was effectively protected from the labeling reagent by ATP or ADP. An average number of 1.3 covalent label per F1 is sufficient for 100% inhibition of the ATPase. About 73% of the radioactive label was found covalently attached to beta subunits, 9% on alpha, practically none on gamma, delta, and epsilon. Cleavage of the labeled enzyme by pepsin and sequencing of the major radioactive peptide showed that the labeled amino acid residue in beta subunit was Lys beta 162. These results show that Lys beta 162 is indeed at the active site of F1 as assumed in the recently proposed models (Fry, D. C., Kuby, S. A., and Mildvan, A. S. (1986) Proc. Natl. Acad. Sci. U. S. A. 83, 907-911; Duncan, I. M., Parsonage, D., and Senior, A. E. (1986) FEBS Lett. 208, 1-6).

  5. Revised Thomas-Fermi approximation for singular potentials

    NASA Astrophysics Data System (ADS)

    Dufty, James W.; Trickey, S. B.

    2016-08-01

    Approximations for the many-fermion free-energy density functional that include the Thomas-Fermi (TF) form for the noninteracting part lead to singular densities for singular external potentials (e.g., attractive Coulomb). This limitation of the TF approximation is addressed here by a formal map of the exact Euler equation for the density onto an equivalent TF form characterized by a modified Kohn-Sham potential. It is shown to be a "regularized" version of the Kohn-Sham potential, tempered by convolution with a finite-temperature response function. The resulting density is nonsingular, with the equilibrium properties obtained from the total free-energy functional evaluated at this density. This new representation is formally exact. Approximate expressions for the regularized potential are given to leading order in a nonlocality parameter, and the limiting behavior at high and low temperatures is described. The noninteracting part of the free energy in this approximation is the usual Thomas-Fermi functional. These results generalize and extend to finite temperatures the ground-state regularization by R. G. Parr and S. Ghosh [Proc. Natl. Acad. Sci. U.S.A. 83, 3577 (1986), 10.1073/pnas.83.11.3577] and by L. R. Pratt, G. G. Hoffman, and R. A. Harris [J. Chem. Phys. 88, 1818 (1988), 10.1063/1.454105] and formally systematize the finite-temperature regularization given by the latter authors.

  6. Eukaryotic signature proteins of Prosthecobacter dejongeii and Gemmata sp. Wa-1 as revealed by in silico analysis.

    PubMed

    Staley, James T; Bouzek, Heather; Jenkins, Cheryl

    2005-02-01

    The genomes of representatives of three bacterial phyla have been compared with the list of 347 eukaryotic signature proteins (ESPs) derived by Hartman and Fedorov [Proc. Natl. Acad. Sci. USA 99 (2002) 1420]. The species included Prosthecobacter dejongeii of the Verrucomicrobia phylum, Gemmata sp. Wa-1 of the Planctomycetes phylum and Caulobacter crescentus of the Proteobacteria. The protist Trypanosoma brucei was used as a eukaryotic control. P. dejongeii had unique ERGO blast matches to alpha-, beta-, and gamma-tubulin, to Set2, a transcriptional factor associated with eukaryotic DNA, and to LAMMER protein kinase for a total of 10 high-scoring ESP matches altogether. Gemmata sp. Wa-1 shared four of its 17 high-scoring ESP matches with P. dejongeii, and that information coupled with other genomic data provides strong support that these two phyla are related to one another. If the ESP list is an accurate listing of unique eukaryotic proteins, then the low number of high-scoring matches between the proteins of these two bacteria with the list raises doubts about these phyla being direct ancestors of the Eucarya. However, this does not rule out the possibility that ancestral members of either the Verrucomicrobia or Planctomycetes may have played an important role in the evolution of a proto-eukaryotic organism. PMID:15667994

  7. X-ray structural characterization of imidazolylcobalamin and histidinylcobalamin: cobalamin models for aquacobalamin bound to the B12 transporter protein transcobalamin.

    PubMed

    Hannibal, Luciana; Bunge, Scott D; van Eldik, Rudi; Jacobsen, Donald W; Kratky, Christoph; Gruber, Karl; Brasch, Nicola E

    2007-04-30

    The X-ray structures of imidazolylcobalamin (ImCbl) and histidinylcobalamin (HisCbl) are reported. These structures are of interest given that the recent structures of human and bovine transcobalamin prepared in their holo forms from aquacobalamin show a histidine residue of the metalloprotein bound at the beta-axial site of the cobalamin (Wuerges, J. et al. Proc. Natl. Acad. Sci. U.S.A. 2006, 103, 4386-4391). The beta-axial Co-N bond distances for ImCbl and HisCbl are 1.94(1) and 1.951(7) A, respectively. The alpha-axial Co-N bond distances to the 5,6-dimethylbenzimidazole are 2.01(1) and 1.979(8) A for ImCbl and HisCbl, respectively, and are typical for cobalamins with weak sigma-donor ligands at the beta-axial site. The corrin fold angles of 11.8(3) degrees (ImCbl) and 12.0(3) degrees (HisCbl) are smaller than those typically observed for cobalamins.

  8. Experiencias sobre el impacto del Programa de Formación en Ética de la Investigación Biomédica y Psicosocial en el ámbito de la salud mental y la investigación conductual.

    PubMed

    Barrios, Liliana Mondragón

    2012-01-01

    El propósito de este trabajo es presentar el impacto y la integración que los conocimientos adquiridos en el Programa Internacional de Formación en Ética de la Investigación Biomédica y Psicosocial de la Universidad de Chile han tenido en mi experiencia profesional, en el ámbito de la investigación psicosocial en un Instituto de Salud de México. Para este objetivo, expondré tres áreas en las cuales se ha podido evidenciar tal impacto: trabajo en los comités de ética, desarrollo de programas de académicos en bioética e investigación y publicación sobre ética y bioética. El motivo que me llevó a incursionar en el Programa fue que su enseñanza vincula la investigación psicosocial con la ética y la bioética, lo cual me permitió dirigir este tipo de reflexión hacia problemas como violencia, suicidio, adicciones, depresión y salud mental, y a nuevos campos como los estudios comunitarios, con poblaciones en riesgo o vulnerables, en los cuales las diversas implicaciones son difíciles de indagar.

  9. Introduction of protein or DNA delivered via recombinant Salmonella typhimurium into the major histocompatibility complex class I presentation pathway of macrophages.

    PubMed

    Catic, A; Dietrich, G; Gentschev, I; Goebel, W; Kaufmann, S H; Hess, J

    1999-02-01

    Recombinant (r) Salmonella typhimurium aroA strains which display the hen egg ovalbumin OVA(257-264) peptide SIINFEKL in secreted form were constructed. In addition, attenuated rS. typhimurium pcDNA-OVA constructs harbouring a eukaryotic expression plasmid encoding complete OVA were used to introduce the immunodominant OVA(257-264) epitope into the major histocompatibility complex (MHC) class I presentation pathway. Both modes of antigen delivery (DNA and protein) by Salmonella vaccine carriers stimulated OVA(257-264)-specific CD8 T-cell hybridomas. An in vitro infection system was established that allowed both rSalmonella carrier devices to facilitate MHC class I delivery of OVA(257-264) by coexpression of listeriolysin (Hly) or by coinfection with rS. typhimurium Hlys (Hess J., Gentschev I., Miko D., Welzel M., Ladel C., Goebel W., Kaufmann S.H.E., Proc. Natl. Acad. Sci. USA 93 (1996) 1458-1463). Coexpression of Hly and coinfection with rS. typhimurium Hlys slightly improved MHC class I processing of OVA. Our data provide further evidence for the feasibility of attenuated, Hly-expressing rS. typhimurium carriers secreting heterologous antigens or harbouring heterologous DNA as effective vaccines for stimulating CD8 T cells in addition to CD4 T cells. PMID:10594975

  10. Protection against murine listeriosis by an attenuated recombinant Salmonella typhimurium vaccine strain that secretes the naturally somatic antigen superoxide dismutase.

    PubMed

    Hess, J; Dietrich, G; Gentschev, I; Miko, D; Goebel, W; Kaufmann, S H

    1997-04-01

    A recombinant (r)-Salmonella typhimurium aroA vaccine strain was constructed which secretes the naturally somatic protein of Listeria monocytogenes, superoxide dismutase (SOD), by the HlyB/HlyD/TolC export machinery. Vaccine efficacy of the SOD-bearing carrier strain was compared with that of the p60-secreting construct, S. typhimurium p60s (J. Hess, I. Gentschev, D. Miko, M. Welzel, C. Ladel, W. Goebel, and S. H. E. Kaufmann, Proc. Natl. Acad. Sci. USA 93:1458-1463, 1996). Vaccination of mice with both constructs induced protection against a lethal challenge with the intracellular pathogen, L. monocytogenes. While the somatic listerial antigen, SOD, is immunologically uncharacterized, the naturally secreted protein of L. monocytogenes, p60, is known to be highly immunogenic. Our data emphasize the high vaccine potential of r-Salmonella constructs secreting antigens of somatic or secreted origin. Moreover, they suggest that the HlyB/HlyD/TolC-based antigen delivery system with attenuated Salmonella spp. as the carrier is capable of potentiating the immune response against foreign proteins independent from their immunogenicity in and display by the natural host. PMID:9119463

  11. From the Cover: Cooperative extraction of membrane nanotubes by molecular motors

    NASA Astrophysics Data System (ADS)

    Leduc, Cécile; Campàs, Otger; Zeldovich, Konstantin B.; Roux, Aurélien; Jolimaitre, Pascale; Bourel-Bonnet, Line; Goud, Bruno; Joanny, Jean-François; Bassereau, Patricia; Prost, Jacques

    2004-12-01

    In eukaryotic cells, nanotubes represent a substantial fraction of transport intermediates between organelles. They are extracted from membranes by molecular motors walking along microtubules. We previously showed that kinesins fixed on giant unilamellar vesicles in contact with microtubules are sufficient to form nanotubes in vitro. Motors were attached to the membrane through beads, thus facilitating cooperative effects. Koster et al. [Koster, G., VanDuijn, M., Hofs, B. & Dogterom, M. (2003) Proc. Natl. Acad. Sci. USA 100, 15583-15588] proposed that motors could dynamically cluster at the tip of tubes when they are individually attached to the membrane. We demonstrate, in a recently designed experimental system, the existence of an accumulation of motors allowing tube extraction. We determine the motor density along a tube by using fluorescence intensity measurements. We also perform a theoretical analysis describing the dynamics of motors and tube growth. The only adjustable parameter is the motor binding rate onto microtubules, which we measure to be 4.7 ± 2.4 s-1. In addition, we quantitatively determine, for a given membrane tension, the existence of a threshold in motor density on the vesicle above which nanotubes can be formed. We find that the number of motors pulling a tube can range from four at threshold to a few tens away from it. The threshold in motor density (or in membrane tension at constant motor density) could be important for the understanding of membrane traffic regulation in cells. giant unilamellar vesicle | intracellular transport | kinesin | membrane tubule | traffic jam

  12. An inbred line of transgenic mice expressing an internally deleted gene for type II procollagen (COL2A1). Young mice have a variable phenotype of a chondrodysplasia and older mice have osteoarthritic changes in joints.

    PubMed Central

    Helminen, H J; Kiraly, K; Pelttari, A; Tammi, M I; Vandenberg, P; Pereira, R; Dhulipala, R; Khillan, J S; Ala-Kokko, L; Hume, E L

    1993-01-01

    Studies were carried out on a line of transgenic mice that expressed an internally deleted COL2A1 gene and developed a phenotype resembling human chondrodysplasias (Vandenberg et al. 1991. Proc. Natl. Acad. Sci. USA. 88:7640-7644. Marked differences in phenotype were observed with propagation of the mutated gene in an inbred strain of mice in that approximately 15% of the transgenic mice had a cleft palate and a lethal phenotype, whereas the remaining mice were difficult to distinguish from normal littermates. 1-d- and 3-mo-old transgenic mice that were viable showed microscopic signs of chondrodysplasia with reduced amounts of collagen fibrils in the cartilage matrix, dilatation of the rough surfaced endoplasmic reticulum in the chondrocytes, and decrease of optical path difference in polarized light microscopy. The transgenic mice also showed signs of disturbed growth as evidenced by lower body weight, lower length and weight of the femur, decreased bone collagen, decreased bone mineral, and decreased resistance of bone to breakage. Comparisons of mice ranging in age from 1 d to 15 mo demonstrated that there was decreasing evidence of a chondrodysplasia as the mice grew older. Instead, the most striking feature in the 15-mo-old mice were degenerative changes of articular cartilage similar to osteoarthritis. Images PMID:8349798

  13. The Boussinesq Debate: Reversibility, Instability, and Free Will.

    PubMed

    Michael Mueller, Thomas

    2015-12-01

    In 1877, a young mathematician named Joseph Boussinesq presented a mémoire to the Académie des sciences which demonstrated that some differential equations may have more than one solution. Boussinesq linked this fact to indeterminism and to a possible solution to the free will versus determinism debate. Boussinesq's main interest was to reconcile his philosophical and religious views with science by showing that matter and motion do not suffice to explain all there is in the world. His argument received mixed criticism that addressed both his philosophical views and the scientific content of his work, pointing to the physical "realisticness" of multiple solutions. While Boussinesq proved to be able to face the philosophical criticism, the scientific objections became a serious problem, thus slowly moving the focus of the debate from the philosophical plane to the scientific one. This change of perspective implied a wide discussion on topics such as instability, the sensitivity to initial conditions, and the conservation of energy. The Boussinesq debate is an example of a philosophically motivated debate that transforms into a scientific one, an example of the influence of philosophy on the development of science.

  14. In Situ Association of Calvin Cycle Enzymes, Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Activase, Ferredoxin-NADP+ Reductase, and Nitrite Reductase with Thylakoid and Pyrenoid Membranes of Chlamydomonas reinhardtii Chloroplasts as Revealed by Immunoelectron Microscopy.

    PubMed Central

    Suss, K. H.; Prokhorenko, I.; Adler, K.

    1995-01-01

    The in situ localization of the chloroplast enzymes ribulose-1,5-bisphosphate carboxylase (Rubisco), Rubisco activase, ribose-5-phosphate isomerase, glyceraldehyde-3-phosphate dehydrogenase, aldolase, nitrite reductase, ferredoxin-NADP+ reductase, and H+-ATP synthase was studied by immunoelectron microscopy in Chlamydomonas reinhardtii. Immunogold labeling revealed that, despite Rubisco in the pyrenoid matrix, Calvin cycle enzymes, Rubisco activase, nitrite reductase, ferredoxin-NADP+ reductase, and H+-ATP synthase are associated predominantly with chloroplast thylakoid membranes and the inner surface of the pyrenoid membrane. This is in accord with previous enzyme localization studies in higher plants (K.H. Suss, C. Arkona, R. Manteuffel, K. Adler [1993] Proc Natl Acad Sci USA 90: 5514-5518). Pyrenoid tubules do not contain these enzymes. The pyrenoid matrix consists of Rubisco but is devoid of the other photosynthetic enzymes investigated. Evidence for the occurrence of two Rubisco forms differing in their spatial localization has also been obtained: Rubisco form I appears to be membrane associated like other Calvin cycle components, whereas Rubisco form II is confined to the pyrenoid matrix. It is proposed that enzyme form I represents an active Rubisco when assembled into Calvin cycle enzyme complexes, whereas Rubisco form II may be part of a CO2-concentrating mechanism. Pyrenoidal Calvin cycle complexes are thought to be highly active in CO2 fixation and important for the synthesis of starch around the pyrenoid. PMID:12228443

  15. Proteolytic processing of a coleopteran-specific delta-endotoxin produced by Bacillus thuringiensis var. tenebrionis.

    PubMed Central

    Carroll, J; Li, J; Ellar, D J

    1989-01-01

    Insecticidal protein delta-endotoxin crystals harvested from sporulated cultures of Bacillus thuringiensis var. tenebrionis contain a major polypeptide of 67 kDa and minor polypeptides of 73, 72, 55 and 46 kDa. During sporulation, only the 73 kDa polypeptide could be detected at stage I. The 67 kDa polypeptide was first detected at stage II and increased in concentration throughout the later stages of sporulation and after crystal release, with a concomitant decrease in the 73 kDa polypeptide. This change could be blocked by the addition of proteinase inhibitors. Trypsin or insect-gut-extract treatment of the delta-endotoxin crystals after solubilization resulted in a cleavage product of 55 kDa with asparagine-159 of the deduced amino acid sequence of the toxin [Höfte, Seurinck, van Houtven & Vaeck (1987) Nucleic Acids Res. 15, 71-83; Sekar, Thompson, Maroney, Bookland & Adang (1987) Proc. Natl. Acad. Sci. U.S.A. 84, 7036-7040; McPherson, Perlak, Fuchs, Marrone, Lavrik & Fischhoff (1988) Biotechnology 6, 61-66] at the N-terminus. This polypeptide was found to be as toxic in vivo as native delta-endotoxin. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:2549968

  16. Kinetic studies on the control of the bean rust fungus (Uromyces phaseoli L.) by an inhibitor of polyamine biosynthesis.

    PubMed

    Rajam, M V; Weinstein, L H; Galston, A W

    1986-01-01

    alpha-Difluoromethylornithine (DFMO), a specific and irreversible inhibitor of the polyamine biosynthetic enzyme ornithine decarboxylase, effectively inhibits mycelial growth of several phytopathogenic fungi on defined media in vitro and provides systemic protection of bean plants against infection by Uromyces phaseoli L. race 0 (MV Rajam, AW Galston 1985 Plant Cell Physiol 26: 683-692; MV Rajam et al. 1985 Proc Natl Acad Sci USA 82: 6874-6878). We now find that application of 0.5 millimolar DFMO to unifoliolate leaves of Pinto beans up to 3 days after inoculation with uredospores of U. phaseoli completely inhibits the growth of the pathogen, while application 4 or 5 days after inoculation results in partial protection against the pathogen. Spores do not germinate on the surface of unifoliolate leaves treated with DFMO 1 day before infection, but addition of spermidine to the DFMO treatments partially reverses the inhibitory effect. The titer of polyamines in bean plants did not decline after DFMO treatment; rather, putrescine and spermidine contents actually rose, probably due to the known but paradoxical stimulation of arginine decarboxylase activity by DFMO. PMID:11539088

  17. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma Panhandle, USA

    NASA Astrophysics Data System (ADS)

    Bement, Leland C.; Madden, Andrew S.; Carter, Brian J.; Simms, Alexander R.; Swindle, Andrew L.; Alexander, Hanna M.; Fine, Scott; Benamara, Mourad

    2014-02-01

    High levels of nanodiamonds (nds) have been used to support the transformative hypothesis that an extraterrestrial (ET) event (comet explosion) triggered Younger Dryas changes in temperature, flora and fauna assemblages, and human adaptations [Firestone RB, et al. (2007) Proc Natl Acad Sci USA 104(41):16016-16021]. We evaluate this hypothesis by establishing the distribution of nds within the Bull Creek drainage of the Beaver River basin in the Oklahoma panhandle. The earlier report of an abundance spike of nds in the Bull Creek I Younger Dryas boundary soil is confirmed, although no pure cubic diamonds were identified. The lack of hexagonal nds suggests Bull Creek I is not near any impact site. Potential hexagonal nds at Bull Creek were found to be more consistent with graphene/graphane. An additional nd spike is found in deposits of late Holocene through the modern age, indicating nds are not unique to the Younger Dryas boundary. Nd distributions do not correlate with depositional environment, pedogenesis, climate perturbations, periods of surface stability, or cultural activity.

  18. Potential of ZrO clusters as replacement Pd catalyst.

    PubMed

    Behera, Swayamprabha; King, Nicholas; Samanta, Devleena; Jena, Puru

    2014-07-21

    Atomic clusters with specific size and composition and mimicking the chemistry of elements in the periodic table are commonly known as superatoms. It has been suggested that superatoms could be used to replace elements that are either scarce or expensive. Based on a photoelectron spectroscopy experiment of negatively charged ions, Castleman and co-workers [Proc. Natl. Acad. Sci. U.S.A. 107, 975 (2010)] have recently shown that atoms of Ni, Pd, and Pt which are well known for their catalytic properties, have the same electronic structure as their counterpart isovalent diatomic species, TiO, ZrO, and WC, respectively. Based on this similarity they have suggested that ZrO, for example, could be a replacement catalyst for Pd. Since catalysts are seldom single isolated atoms, one has to demonstrate that clusters of ZrO also have the same electronic structure as same sized Pd clusters. To examine if this is indeed the case, we have calculated the geometries, electronic structure, electron affinity, ionization potential, and hardness of Pdn and (ZrO)n clusters (n = 1-5). We further studied the reaction of these clusters in neutral and charged forms with H2, O2, and CO and found it to be qualitatively different in most cases. These results obtained using density functional theory with hybrid B3LYP functional do not support the view that ZrO clusters can replace Pd as a catalyst. PMID:25053314

  19. Numerical bifurcation analysis of the pattern formation in a cell based auxin transport model.

    PubMed

    Draelants, Delphine; Broeckhove, Jan; Beemster, Gerrit T S; Vanroose, Wim

    2013-11-01

    Transport models of growth hormones can be used to reproduce the hormone accumulations that occur in plant organs. Mostly, these accumulation patterns are calculated using time step methods, even though only the resulting steady state patterns of the model are of interest. We examine the steady state solutions of the hormone transport model of Smith et al. (Proc Natl Acad Sci USA 103(5):1301-1306, 2006) for a one-dimensional row of plant cells. We search for the steady state solutions as a function of three of the model parameters by using numerical continuation methods and bifurcation analysis. These methods are more adequate for solving steady state problems than time step methods. We discuss a trivial solution where the concentrations of hormones are equal in all cells and examine its stability region. We identify two generic bifurcation scenarios through which the trivial solution loses its stability. The trivial solution becomes either a steady state pattern with regular spaced peaks or a pattern where the concentration is periodic in time.

  20. Successive explosions in Mumbai the economic center of India.

    PubMed

    Krishnamurthy, R; Daundkar, B B; Malve, M K

    2006-01-01

    Terrorist activities in India are increasing day by day with sophistication in modus operandi. Mumbai the economic center of India was attacked by a series of bomb blasts at twelve different places within a span of an hour on 12th March 1993. The main explosive used was RDX [Krishnamurthy R, Malve MK, Shinde BM. J Indian Acad Forensic Sci 1996;35(1& 2):46-61.]. After about 10 years, terrorist activity of late has again erupted taking a toll on innocent lives, with the use of explosives causing death and destruction. On 2.12.02 a public bus at Ghatkopar was blown up by an improvised explosive device (IED) with two casualties. On 27.1.03 the public vegetable market at Vileparle was targeted causing heavy damage and panic among common people. On 13.3.03 a fully packed local train compartment at Mulund railway station was blown up by an improved explosive device and the casualties ranged up to 10. In most of the explosions the explosives used were RDX, NC-NG, etc. The blasts that occurred at the Zaveri bazaar and the gateway of India on 25/8/03 showed the presence of big craters at the blast site and on analysis the presence of RDX and petroleum oil. PMID:17055401