410 research outputs found
Seismic Pressure Distribution on Retaining Wall with Reinforced Earth Backfill
An analysis for determination of lateral thrust on a rigid retaining wall with reinforced earth backfill under seismic condition is described in this paper. The backfill is reinforced with horizontally laid unattached strips and an equivalent horizontal static force replaces the dynamic force. A Coulomb wedge is assumed to develop at limiting equilibrium. Analysis indicates substantial reduction in pressures on the wall due to reinforcement. An optimum length of reinforcing strips of 60 percent of height of wall is indicated
Private Incremental Regression
Data is continuously generated by modern data sources, and a recent challenge
in machine learning has been to develop techniques that perform well in an
incremental (streaming) setting. In this paper, we investigate the problem of
private machine learning, where as common in practice, the data is not given at
once, but rather arrives incrementally over time.
We introduce the problems of private incremental ERM and private incremental
regression where the general goal is to always maintain a good empirical risk
minimizer for the history observed under differential privacy. Our first
contribution is a generic transformation of private batch ERM mechanisms into
private incremental ERM mechanisms, based on a simple idea of invoking the
private batch ERM procedure at some regular time intervals. We take this
construction as a baseline for comparison. We then provide two mechanisms for
the private incremental regression problem. Our first mechanism is based on
privately constructing a noisy incremental gradient function, which is then
used in a modified projected gradient procedure at every timestep. This
mechanism has an excess empirical risk of , where is the
dimensionality of the data. While from the results of [Bassily et al. 2014]
this bound is tight in the worst-case, we show that certain geometric
properties of the input and constraint set can be used to derive significantly
better results for certain interesting regression problems.Comment: To appear in PODS 201
Probing the single-particle character of rotational states in F using a short-lived isomeric beam
A beam containing a substantial component of both the ,
ns isomeric state of F and its , 109.77-min ground
state has been utilized to study members of the ground-state rotational band in
F through the neutron transfer reaction , in inverse kinematics.
The resulting spectroscopic strengths confirm the single-particle nature of the
13/2 band-terminating state. The agreement between shell-model
calculations, using an interaction constructed within the shell, and our
experimental results reinforces the idea of a single-particle/collective
duality in the descriptions of the structure of atomic nuclei
Association between longer hospitalization and development of de novo donor specific antibodies in simultaneous liver–kidney transplant recipients
© 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Background:De novo Donor Specific Antibodies (DSA) are considered as a risk factor for the kidney allograft outcomes in recipients after simultaneous liver–kidney transplantation (SLKT). We hypothesized that length of hospital stay (LOS) might be associated with de novo DSA development of due to the increased likelihood of receiving blood transfusions with reduced immunosuppressive regimens. Methods: This study is a single-center, retrospective cohort study consisting of 85 recipients who underwent SLKT from 2009 to 2018 in our hospital. We divided the patients into two groups according to LOS [long hospital stay (L) group (LOS \u3e14 days) and short hospital stay (S) group (LOS ≤14 days)]. Propensity score (PS) has been created using logistic regression to predict LOS greater than median of 14 days. The association between the presence of de novo DSA and LOS was assessed by logistic regression models adjusted for PS. Results: The mean age at transplantation of the entire cohort was 55.5 ± 10.1 years. Sixty percent of the recipients were male and Caucasian. Median LOS in (L) group was three-fold longer than (S) group [L: median 30 days (IQR: 21–52), S: median 8.5 days (IQR: 7–11)]. Eight patients developed de novo DSA after SLKT (9.4%), all of them were in (L) group. Longer LOS was significantly associated with higher risk of development of de novo DSA in unadjusted (OR+ each 5 days: 1.09, 95% CI:1.02–1.16) and PS adjusted (OR+ each 5 days: 1.11, 95% CI:1.02–1.21) analysis. Conclusion: Longer hospitalization is significantly associated with the development of de novo DSA in SLKT
Ultrafast optical generation of coherent phonons in CdTe1-xSex quantum dots
We report on the impulsive generation of coherent optical phonons in
CdTe0.68Se0.32 nanocrystallites embedded in a glass matrix. Pump probe
experiments using femtosecond laser pulses were performed by tuning the laser
central energy to resonate with the absorption edge of the nanocrystals. We
identify two longitudinal optical phonons, one longitudinal acoustic phonon and
a fourth mode of a mixed longitudinal-transverse nature. The amplitude of the
optical phonons as a function of the laser central energy exhibits a resonance
that is well described by a model based on impulsive stimulated Raman
scattering. The phases of the coherent phonons reveal coupling between
different modes. At low power density excitations, the frequency of the optical
coherent phonons deviates from values obtained from spontaneous Raman
scattering. This behavior is ascribed to the presence of electronic impurity
states which modify the nanocrystal dielectric function and, thereby, the
frequency of the infrared-active phonons
An analysis of yield variation among long-duration pigeonpea genotypes in relation to season, irrigation and plant population
The response of eight long-duration pigeonpea [Cajanus cajan (L) Millsp.] genotypes to irrigation was studied at Gwalior in Central India during the 1990–91, 1991–92 and 1992–93 growing seasons on an Inceptisol. The crop was grown at two spacings as it was expected that crop density could interact with the crop's ability to extract soil moisture. The irrigation treatment received furrow irrigation four times during the 1990–91 and 1992–93 seasons and twice during the 1991–92 season. Grain yields of all genotypes were 11 % higher when planted at higher density than at low density. There was a differential variation in yield and harvest index among genotypes due to season but not due to spacing and irrigation suggesting the validity of the present approach of testing genotypes under optimum conditions. Grain yield declined by 21 % from the 1990 to 1992 season. The decline was > 1 t/ha in some cultivars (ICPL 366, GW3), and between 0·5 and 1·0 t/ha in others (NP [WR] 15, ICP 87143 and ICPL 84072). In others (Bahar, ICP 9174, ICP 8860) the yield fluctuation was < 0·5 t/ha. The genotypes' mean yields were as high as 2·7 t/ha for ICPL 87143, ICPL 84072 and ICPL 366. There was a significant reduction in both grain yield (16 %), and also above-ground plant dry mass (18 %) due to soil moisture limitation in the unirrigated treatment. Both the above-ground plant dry mass and grain yields were significantly more at high plant density than at lower plant density especially with irrigation. The genotypes were found to differ in their response to production environment (irrigation, spacing and to the undefined differences of the 3 years). Genotypic variation in yield within a production environment was found to vary in relation to changes in harvest index and across environment (irrigation, seasons) due to variation in total dry matter production. A lack of negative relationship between the total dry matter and harvest index suggests the possibility of optimizing both for obtaining higher yield from long-duration genotype
Which circulating antioxidant vitamins are confounded by socioeconomic deprivation? The MIDSPAN family study
<p><b>Background:</b> Antioxidant vitamins are often described as having “independent” associations with risk of cancer, cardiovascular disease (CVD) and mortality. We aimed to compare to what extent a range of antioxidant vitamins and carotenoids are associated with adulthood and childhood markers of socioeconomic deprivation and to adverse lifestyle factors.</p>
<p><b>Methods and Findings:</b> Socioeconomic and lifestyle measures were available in 1040 men and 1298 women from the MIDSPAN Family Study (30–59 years at baseline) together with circulating levels of vitamins A, C, E, and carotenoids (α-carotene, β-carotene, lutein and lycopene). Markers of socioeconomic deprivation in adulthood were consistently as strongly associated with lower vitamin C and carotenoid levels as markers of adverse lifestyle; the inverse association with overcrowding was particularly consistent (vitamin C and carotenoids range from 19.1% [95% CI 30.3–6.0] to 38.8% [49.9–25.3] lower among those in overcrowded residencies). These associations were consistent after adjusting for month, classical CVD risk factors, body mass index, physical activity, vitamin supplements, dietary fat and fibre intake. Similar, but weaker, associations were seen for childhood markers of deprivation. The association of vitamin A or E were strikingly different; several adult adverse lifestyle factors associated with higher levels of vitamin A and E, including high alcohol intake for vitamin A (9.5% [5.7–13.5]) and waist hip ratio for vitamin E (9.5% [4.8–14.4]), with the latter associations partially explained by classical risk factors, particularly cholesterol levels.</p>
<p><b>Conclusions:</b> Plasma vitamin C and carotenoids have strong inverse associations with adulthood markers of social deprivation, whereas vitamin A and E appear positively related to specific adverse lifestyle factors. These findings should help researchers better contextualize blood antioxidant vitamin levels by illustrating the potential limitations associated with making causal inferences without consideration of social deprivation.</p>
Myliobatis freminvillii, bullnose eagle ray
The Bullnose Eagle Ray (Myliobatis freminvillii) is a medium-sized (to 106 cm disc width) demersal coastal eagle ray that occurs in the Northwest, Western Central, and Southwest Atlantic Oceans from Massachussetts, USA to the Texas coast of the Gulf of Mexico and from Venezuela to Buenos Aires, Argentina and inhabits continental shelves from the surface to a depth of 122 m. Its is captured by artisanal longlines, gillnets, beach seines and also in industrial shrimp trawls. In the Northwest Atlantic, population trend data are available from a deep-water trawl survey in the northern Gulf of Mexico that reveal steep increases in abundance over 2002-2013. There are no known threats in the Northwest and Western Central Atlantic, but in the Southwest Atlantic artisanal fisheries are intense. Further, there are largely unmanaged commercial trawl and longline fisheries in this area. This inshore eagle ray is exposed to intense and often unmanaged fishing pressure throughout the Southwest Atlantic portion of its range, and it has no refuge at depth. Due to the level of exploitation by widespread artisanal fisheries which lack adequate management, it is suspected that this species has undergone a population reduction of >80% over the past three generation lengths (44 years) in the Atlantic South American part of its range, but is stable in the Northwest and Western Central Atlantic. Overall, based on its range, with almost all threats found in the Southwest Atlantic, and the suspected low productivity of the species, the Bullnose Eagle Ray is suspected to have undergone a population reduction of 30-49% in the past three generation lengths (44 years) due to levels of exploitation, and it is assessed as Vulnerable A2bd.Fil: Carlson, J.. National Marine Fisheries Service; Estados UnidosFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Avalos, C.. Fundacion Mundo Azul; GuatemalaFil: Blanco Parra, M. P.. Universidad de Quintana Roo; MéxicoFil: Briones Bell lloch, A.. Direccion de Regulaciones Pesqueras y Ciencias; CubaFil: Cardeñosa, D.. Florida International University; Estados UnidosFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J.M.. Wildlife Conservation Society; Estados UnidosFil: Derrick, D.. University Fraser Simon; CanadáFil: Espinoza, E.. Direccion Parque Nacional Galapagos; EcuadorFil: Mejía Falla, P. A.. Wildlife Conservation Society; Estados UnidosFil: Morales Saldaña, J. M.. Smithsonian Tropical Research Institute; PanamáFil: Motta, F.. Universidade Federal de Sao Paulo; BrasilFil: Naranjo Elizondo, B.. Universidad de Costa Rica; Costa RicaFil: Pacoureau, N.. University Fraser Simon; CanadáFil: Paesch, L.. Dirección Nacional de Recursos Acuáticos; UruguayFil: Perez Jiménez, J. C.. El Colegio de la Frontera del Sur; MéxicoFil: Rincon, G.. Universidade Federal Do Maranhao.; BrasilFil: Schneider, E. V. C.. Cape Eleuthera Institute; BahamasFil: Simpson, N. J.. Salvageblue; San Vicente y las GranadinasFil: Talwar, B. S.. Florida International University; Estados UnidosFil: Pollom, R.. University Fraser Simon; Canad
Myliobatis goodei, southern eagle ray
The Southern Eagle Ray (Myliobatis goodei) is a medium-sized (to at least 115 cm DW) coastal eagle ray that occurs in the Western Central and Southwest Atlantic Oceans from South Carolina and Florida, USA and Quintana Roo, Mexico to San Jorge Gulf, Santa Cruz, Argentina. It inhabits continental shelves from inshore to depths of 181 m. It is captured using artisanal longlines, gillnets, beach seines, and in industrial shrimp trawls. This species is inferred to be stable or increasing in the Western Central Atlantic, based on its similarity to the Bullnose Eagle Ray (Myliobatis freminvillei). In the Southwest Atlantic artisanal fisheries are intense, further there are largely unmanaged commercial trawl and longline fisheries in many areas. In Brazil, landings of eagle rays have been reduced by 60% over 2000?2012 in Santa Catarina State, and a reduction of 91% in Rio Grande do Sul since the 1980s. This inshore eagle ray has no refuge at depth and is exposed to intense and often unmanaged fishing pressure throughout the Atlantic South American portion of its range and there it is suspected that this species has undergone a population reduction of >80% over the past three generation lengths (44 years), but is stable in the Western Central Atlantic. Overall, based its range with the almost all threats found in the Southwest Atlantic, the suspected low productivity of the species, this species is suspected to have undergone a population reduction of 30 49% in three generation lengths (44 years) due to levels of exploitation, and it is assessed as Vulnerable A2d.Fil: Carlson, J.. National Marine Fisheries Service; Estados UnidosFil: Charvet, P.. Universidade Federal do Paraná; BrasilFil: Avalos Castillo, C.. Fundación Mundo Azul; GuatemalaFil: Blanco Parra, M. P.. Universidad de Quintana Roo; MéxicoFil: Briones Bell lloch, A.. Dirección de Regulaciones Pesqueras y Ciencias; CubaFil: Cardeñosa, D.. Florida International University; Estados UnidosFil: Chiaramonte, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia". Estación Hidrobiológica de Puerto Quequén (sede Quequén); ArgentinaFil: Cuevas, J.M.. Wildlife Conservation Society; Estados UnidosFil: Derrick, D.. University Fraser Simon; CanadáFil: Espinoza, E.. Galapagos National Park Directorate; EcuadorFil: Mejía Falla, P. A.. Wildlife Conservation Society; Estados UnidosFil: Morales Saldaña, J. M.. Smithsonian Tropical Research Institute; PanamáFil: Motta, F.. Universidade Federal Do Sao Paulo; BrasilFil: Naranjo Elizondo, B.. Universidad de Costa Rica; Costa RicaFil: Pacoureau, N.. University Fraser Simon; CanadáFil: Paesch, L.. Direccion Nacional de Recursos Acuaticos ; UruguayFil: Pérez Jiménez, J. C.. El Colegio de la Frontera del Sur; MéxicoFil: Rincon, G.. Universidade Federal Do Maranhao.; BrasilFil: Schneider, E. V. C.. Cape Eleuthera Institute; BahamasFil: Simpson, N. J.. Salvageblue; San Vicente y las GranadinasFil: Talwar, B. S.. Florida International University; Estados UnidosFil: Pollom, R.. University Fraser Simon; Canad
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