The Courts, Daubert, and Environmental Torts: Gatekeepers or Auditors?

Since the decision in Daubert v. Merrell Dow, courts, legal scholars and the scientific community have been struggling with how much judicial activism is required to comply with the gatekeeper role mandated by the Supreme Court. This Article examines the varying conclusions reached on that subject and, relying on several significant Courts of Appeals decisions, suggests how courts can fulfill their Daubert duties without becoming amateur scientists and without expending enormous judicial resources

Perancangan Kapasitor Jalan Untuk Mengoperasikan Motor Induksi 3-Fasa Pada Sistem Tenaga 1-Fasa

The method in operation three- phase induction motor on one-phase power supply by using capacitor had developed in success. This method has good response to rotation, less inrush current and increase power factor correction. The characteristic of the motor usually depend on the place and amplitude of the run capacitor used to the motor. Because of that, the purpose of this research is to give us a new method to place and choice the capacitance of run capacitor in operating three-phase induction motor on one phase power supply. The induction motor used was 1,5 kW, 220/380V; /Y; 50 Hz; 6,2/3,6A; 1400 rpm; B class, 0.84 lag. The result show that, the motor can be operated by using of run capacitor 25,9 F on 95,14% of load rating, 1400 rpm, 0.99 leading power factor, and less current harmonic distortion

Slow Adaptive OFDMA Systems Through Chance Constrained Programming

Adaptive OFDMA has recently been recognized as a promising technique for providing high spectral efficiency in future broadband wireless systems. The research over the last decade on adaptive OFDMA systems has focused on adapting the allocation of radio resources, such as subcarriers and power, to the instantaneous channel conditions of all users. However, such "fast" adaptation requires high computational complexity and excessive signaling overhead. This hinders the deployment of adaptive OFDMA systems worldwide. This paper proposes a slow adaptive OFDMA scheme, in which the subcarrier allocation is updated on a much slower timescale than that of the fluctuation of instantaneous channel conditions. Meanwhile, the data rate requirements of individual users are accommodated on the fast timescale with high probability, thereby meeting the requirements except occasional outage. Such an objective has a natural chance constrained programming formulation, which is known to be intractable. To circumvent this difficulty, we formulate safe tractable constraints for the problem based on recent advances in chance constrained programming. We then develop a polynomial-time algorithm for computing an optimal solution to the reformulated problem. Our results show that the proposed slow adaptation scheme drastically reduces both computational cost and control signaling overhead when compared with the conventional fast adaptive OFDMA. Our work can be viewed as an initial attempt to apply the chance constrained programming methodology to wireless system designs. Given that most wireless systems can tolerate an occasional dip in the quality of service, we hope that the proposed methodology will find further applications in wireless communications

The Turbulent Story of X-ray Bursts: Effects of Shear Mixing on Accreting Neutron Stars

During accretion, a neutron star (NS) is spun up as angular momentum is transported through its liquid surface layers. We study the resulting differentially rotating profile, focusing on the impact this has for type I X-ray bursts. The viscous heating is found to be negligible, but turbulent mixing can be activated. Mixing has the greatest impact when the buoyancy at the compositional discontinuity between accreted matter and ashes is overcome. This occurs preferentially at high accretion rates or low spin frequencies and may depend on the ash composition from the previous burst. We then find two new regimes of burning. The first is ignition in a layer containing a mixture of heavier elements with recurrence times as short as ~5-30 minutes, similar to short recurrence time bursts. When mixing is sufficiently strong, a second regime is found where accreted helium mixes deep enough to burn stably, quenching X-ray bursts altogether. The carbon-rich material produced by stable helium burning would be important for triggering and fueling superbursts.Comment: 3 pages, 3 figures. To appear in the proceedings of "Forty Years of Pulsars: Millisecond Pulsars, Magnetars and More" held in Montreal, Canada, August 12-17, 200

Reflections on Black Lives Matter in the Context of Human Rights and Family Science

- While all lives do matter, the humanity of all lives is not collectively recognized. - Violent contexts place an extraordinary amount of stress on Black youth, families, and communities. - Systematic violence causes multiple transitions in families and threatens families\u27 psychosocial adjustment. - The collectivistic approach served as an adaptive response to varying levels of oppression faced by Black people since arriving in the Americas. - Black Lives Matter has significant implications for the work of family life educators, researchers, and practitioners

Reconnection of superfluid vortex bundles

Using the vortex filament model and the Gross Pitaevskii nonlinear Schroedinger equation, we show that bundles of quantised vortex lines in helium II are structurally robust and can reconnect with each other maintaining their identity. We discuss vortex stretching in superfluid turbulence and show that, during the bundle reconnection process, Kelvin waves of large amplitude are generated, in agreement with the finding that helicity is produced by nearly singular vortex interactions in classical Euler flows.Comment: 10 pages, 7 figure

Evaluating The Effects of Enhanced Processivity and Metal Ions on Translesion DNA Replication Catalyzed by The Bacteriophage T4 DNA Polymerase

The fidelity of DNA replication is achieved in a multiplicative process encompassing nucleobase selection and insertion, removal of misinserted nucleotides by exonuclease activity, and enzyme dissociation from primer/templates that are misaligned due to mispairing. In this study, we have evaluated the effect of altering these kinetic processes on the dynamics of translesion DNA replication using the bacteriophage T4 replication apparatus as a model system. The effect of enhancing the processivity of the T4 DNA polymerase, gp43, on translesion DNA replication was evaluated using a defined in vitro assay system. While the T4 replicase (gp43 in complex with gp45) can perform efficient, processive replication using unmodified DNA, the T4 replicase cannot extend beyond an abasic site. This indicates that enhancing the processivity of gp43 does not increase unambiguously its ability to perform translesion DNA replication. Surprisingly, the replicase composed of an exonuclease-deficient mutant of gp43 was unable to extend beyond the abasic DNA lesion, thus indicating that molecular processes involved in DNA polymerization activity play the predominant role in preventing extension beyond the non-coding DNA lesion. Although neither T4 replicase complex could extend beyond the lesion, there were measurable differences in the stability of each complex at the DNA lesion. Specifically, the exonuclease-deficient replicase dissociates at a rate constant, koff, of 1.1 s−1 while the wild-type replicase remains more stably associated at the site of DNA damage by virtue of a slower measured rate constant (koff 0.009 s−1). The increased lifetime of the wild-type replicase suggests that idle turnover, the partitioning of the replicase from its polymerase to its exonuclease active site, may play an important role in maintaining fidelity. Further attempts to perturb the fidelity of the T4 replicase by substituting Mn2+ for Mg2+ did not significantly enhance DNA synthesis beyond the abasic DNA lesion. The results of these studies are interpreted with respect to current structural information of gp43 alone and complexed with gp45

Spatial and Temporal Vegetation Dynamics: Opportunities and Constraints behind Wildlife Migration in Eastern Africa Savanna Ecosystem

The Africa’s semi-arid savanna ecosystems are characterized by high spatial and temporal variation in forage resources that influence mobility of wildlife population. Rapid changes in vegetation composition in savanna have been documented. These have notably involved transformation of grasslands into denser bushes and infestation of undesirable weed plants accompanied by diminishing ecological carrying capacity of rangelands. The utilization of different landscape units is strongly correlated with the availability of forage species and their nutritional quality. Foraging animals normally respond to the decline in forage quality and availability by moving to other landscapes with relatively higher quality and abundant forage resources. Although, migration of wildlife outside protected areas is ecologically vital for breeding and survival, it foments human-wildlife conflicts. Limited ecological knowledge and nutritional requirements of wildlife coupled with rapid diminishing quality and availability of forage undermine biodiversity conservation efforts. The understanding of spatial–temporal variability of forage resources along with proper wildlife management practices as well as human-wildlife conflict management are highly needed to realize high productivity in livestock industry and wildlife conservation. This chapter reviews the opportunities and constraints of spatial and temporal variability of forage resources and wildlife mobility in Eastern Africa savanna ecosystem