Continuous monitor for gas ratios in a mixture

Fluidic oscillator, incorporating piezoelectric transducer to sense molecular weight of gas mixture, is used to continuously monitor ratio of a mixture of two gases in a flowing system. Device is lightweight, compact, reliable, easy to install, and also produces a simple output signal for controller. Frequency of oscillation is measured and signal converted to ac output

Stimulated Raman Adiabatic Passage via bright state in Lambda medium of unequal oscillator strengths

We consider the population transfer process in a Lambda-type atomic medium of unequal oscillator strengths by stimulated Raman adiabatic passage via bright-state (b-STIRAP) taking into account propagation effects. Using both analytic and numerical methods we show that the population transfer efficiency is sensitive to the ratio q_p/q_s of the transition oscillator strengths. We find that the case q_p>q_s is more detrimental for population transfer process as compared to the case where $q_p \leq q_s$. For this case it is possible to increase medium dimensions while permitting efficient population transfer. A criterion determining the interaction adiabaticity in the course of propagation process is found. We also show that the mixing parameter characterizing the population transfer propagates superluminally

Impact of the European Russia drought in 2010 on the Caspian Sea level

This article has been made available through the Brunel Open Access Publishing Fund - Copyright @ 2011 Arpe et al.The hydrological budgets of the Volga basin (VB) and the Caspian Sea (CS) have been analysed. The components of the water balance for the CS were calculated for the period 1993 to 2010 with emphasis on summer 2010 when a severe drought developed over European Russia. A drop in precipitation over the VB in July 2010 occurs simultaneously with a decrease in evaporation for the same area, an increase of evaporation over the CS itself and a drop of the Caspian Sea level (CSL). The drop in the precipitation over the VB cannot lead to an instantaneous drop of the CSL because the precipitated water needs some months to reach the CS. The delay is estimated here to be 1 to 3 months for excessive precipitation in summer, longer for deficient precipitation and for winter cases. However, the evaporation over the CS itself is considered to be responsible for a simultaneous drop of the CSL from July to September 2010. The impact on the CSL from the precipitation deficit over the VB occurs in the months following the drought. The water deficit from July to September 2010 calculated from the anomalous precipitation minus evaporation over the VB would decrease the CSL by 22 cm, of which only 2 cm had been observed until the end of September (observed Volga River discharge anomaly). So the remaining drop of 20 cm can be expected in the months to follow if no other anomalies happen. In previous studies the precipitation over the VB has been identified as the main cause for CSL changes, but here from a 10 cm drop from beginning of July to end of September, 6 cm can be directly assigned to the enhanced evaporation over the CS itself and 2 cm due to reduced precipitation over the CS. Further periods with strong changes of the CSL are also investigated, which provide some estimates concerning the accuracy of the analysis data. The investigation was possible due to the new ECMWF interim reanalysis data which are used to provide data also for sensitive quantities like surface evaporation and precipitation. The comparison with independent data and the consistency between such data for calculating the water budget over the CS gives a high confidence in the quality of the data used. This investigation provides some scope for making forecasts of the CSL few months ahead to allow for mitigating societal impacts.This article is a contribution to the European project Marie Curie, CLIMSEAS – PIRSES-GA-2009-247512: “Climate Change and Inland Seas: Phenomena, 20 Feedback and Uncertainties. The Physical Science Basis”

Electroblotting onto activated glass. High efficiency preparation of proteins from analytical sodium dodecyl sulfate-polyacrylamide gels for direct sequence analysis

We have developed a new method for the isolation of proteins for microsequencing. It consists of electrophoretic transfer (electroblotting) of proteins or their cleavage fragments onto activated glass filter paper sheets immediately after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The proteins are immobilized on the glass fiber sheets by ionic interactions or by covalent attachment. A wide range of proteins can be prepared in this fashion with no apparent restriction due to solubility, size, charge, or other intrinsic properties of the proteins. As little as 50 ng of the transferred proteins can be detected using Coomassie Blue or fluorescent dye staining procedures and even smaller amounts of radiolabeled proteins by autoradiography. After detection, the protein- containing bands or spots are cut out and inserted directly into a gas- phase sequenator. The piece of glass fiber sheet acts as a support for the protein during the sequencing. Amounts of protein in the 5- to 150- pmol range can be sequenced, and extended runs can be obtained from the blotted samples because of improved stepwise yields and lower backgrounds. The method has been successfully applied to the sequencing of a variety of proteins and peptides isolated from one-dimensional and two-dimensional polyacrylamide gels

Compulsory Labor in a National Emergency: Public Service or Involuntary Servitude? The Case of Crippled Ports

The 13th Amendment ban on involuntary servitude has new relevance as the U.S. grapples with national emergencies such as catastrophic hurricanes, flu pandemics, and terrorism. This Article considers work refusal and coerced work performance in life-threatening employment contexts. Overwhelmed by fear, hundreds of police officers and health care workers abandoned their jobs during Hurricane Katrina. Postal clerks worked against their will without masks in facilities with anthrax. A report by Congress worries that avian flu will cause sick and frightened medical personnel to stay away from work, thus jeopardizing a coherent response to a crisis. How far can the U.S. go in forcing reluctant civilians to perform essential jobs during a national emergency? I explore solutions to this question by hypothesizing a large release of radiation— whether by terror attack, or catastrophic accident, or major earthquake— in a vital Pacific port. These ports have a history of work stoppages that disrupt the nation’s economy. I examine federal government responses if dock workers refused assignments until conditions were safe: (1) The President could declare a national emergency labor dispute under the Taft-Hartley Act, and seek an 80-day back-to-work injunction. (2) Congress could re-enact Section 8 of the War Labor Disputes Act, making it unlawful for dock workers to discontinue production for 30 days and subjecting violators to coercive damages. (3) The president could issue strong executive orders, backed by imprisonment, that regulate employment in ports. At the heart of my analysis, I ask: Would any of these responses violate the Thirteenth Amendment ban on involuntary servitude? Congress and the judiciary have broadened this law, and its enforcement counterpart in 18 U.S.C. § 1584, beyond the abolition of African slave-holding. The Supreme Court in Kozminski defined involuntary servitude as forcing a person to work by physical or legal coercion. But the Supreme Court created 13th Amendment exceptions for transportation work. Robertson upholds a law that bars merchant seamen from quitting work, and imprisons deserters. Butler permits states to conscript citizens to work on highways, on pain of imprisonment. Dock work is similar because ports integrate ships and trucks in a transportation hub. Courts now apply these precedents to new compulsory activities, such as mandatory public service for graduation. Moreover, Kozminski reaffirmed Robertson and Butler as precedents. Thus, the Constitution would be unlikely to shield dock workers from involuntary labor. This has troubling implications for employees who have recently worked in national emergencies, and may do so again. Employees who work to alleviate avian flu or other catastrophic health threats are also at risk for compulsory labor that exposes them to extraordinary hazards. I conclude with a legislative proposal to strengthen individual rights. As my research shows, courts that are presented with national emergency disputes rarely side with the individual who stands in the way of the public’s welfare. Without a more balanced labor policy to address emerging crises, the nation may realize belatedly “that when we allow fundamental freedoms to be sacrificed in the name of real or perceived emergency, we invariably come to regret it.

Adiabatic tracking for photo- and magneto-association of Bose-Einstein condensates with Kerr nonlinearities

We develop the method of adiabatic tracking for photo- and magneto-association of Bose-Einstein atomic condensates with models that include Kerr type nonlinearities. We show that the inclusion of these terms can produce qualitatively important modifications in the adiabatic dynamics, like the appearance of bifurcations, in which the trajectory that is being tracked loses its stability. As a consequence the adiabatic theorem does not apply and the adiabatic transfer can be strongly degraded. This degradation can be compensated by using fields that are strong enough compared with the values of the Kerr terms. The main result is that, despite these potentially detrimental features, there is always a choice of the detuning that leads to an efficient adiabatic tracking, even for relatively weak fields