A microfluidic oligonucleotide synthesizer

De novo gene and genome synthesis enables the design of any sequence without the requirement of a pre-existing template as in traditional genetic engineering methods. The ability to mass produce synthetic genes holds great potential for biological research, but widespread availability of de novo DNA constructs is currently hampered by their high cost. In this work, we describe a microfluidic platform for parallel solid phase synthesis of oligonucleotides that can greatly reduce the cost of gene synthesis by reducing reagent consumption (by 100-fold) while maintaining a 100 pmol synthesis scale so there is no need for amplification before assembly. Sixteen oligonucleotides were synthesized in parallel on this platform and then successfully used in a ligation-mediated assembly method to generate DNA constructs 200 bp in length

Understanding Heisenberg's 'Magical' Paper of July 1925: a New Look at the Calculational Details

In July 1925 Heisenberg published a paper [Z. Phys. 33, 879-893 (1925)] which ended the period of `the Old Quantum Theory' and ushered in the new era of Quantum Mechanics. This epoch-making paper is generally regarded as being difficult to follow, perhaps partly because Heisenberg provided few clues as to how he arrived at the results which he reported. Here we give details of calculations of the type which, we suggest, Heisenberg may have performed. We take as a specific example one of the anharmonic oscillator problems considered by Heisenberg, and use our reconstruction of his approach to solve it up to second order in perturbation theory. We emphasize that the results are precisely those obtained in standard quantum mechanics, and suggest that some discussion of the approach - based on the direct computation of transition amplitudes - could usefully be included in undergraduate courses in quantum mechanics.Comment: 24 pages, no figures, Latex, submitted to Am. J. Phy

Ultrasound Guidance for Vaginal Drainage of Postoperative Pelvic Hematoma: A Case Report

Background: Postoperative pelvic fluid collection is almost a universal consequence of gynecologic surgery. At one end of the spectrum are minimal collections of peritoneal fluid or blood that are clinically inconsequential. At the other end are hematomas and abscesses requiring active intervention for the patient to recover

Misuse of the Antitrust Laws: The Competitor Plaintiff

In this article we ask (1) under what circumstances are competitor suits meritorious, and (2) do existing rules, such as those requiring proof of market power or other so-called filters and the requirement that plaintiffs suffer antitrust injury, afford a reasonable prospect of eliminating anticompetitive misuses of the remedy by competitor plaintiffs? We evaluate a sample of seventy-four cases in which plaintiffs sued their rivals to learn how competitor plaintiffs use the private antitrust remedy. And because many of these cases allege anticompetitive exclusionary practices, we consider how recent theories of exclusionary practices may be used to support competitor claims. The sample, which was drawn from over 1900 private antitrust cases filed in five federal district courts over an eleven-year period, offers three advantages. First, we can avoid the biases associated with studies that rely exclusively on litigated cases. As is well known, these do not represent the population of claims filed and, as a result, research that relies solely on published opinions cannot offer accurate insights into the overall character of private antitrust enforcement. Second, the time period covered by our sample permits an inquiry into the effectiveness of the Supreme Court\u27s 1977 decision in Brunswick Corp. v. Pueblo Bowl-0-Mat, Inc., which articulated the principle that plaintiffs must allege that they suffered antitrust injury in preventing misuse (at least from the viewpoint of economic efficiency) of the remedy by competitors. Third, a substantial number of the competitor cases in the sample involve claims of anticompetitive exclusion and so allow us to gauge the quality of such claims

Do Work Barriers for Justice-Impacted Individuals Incentivize Criminal Behavior?

This study explores the legal barriers created by state governments for justice-impacted individuals. The more work barriers the state creates for someone with a criminal record, the more attractive illegal activities become. We examine differences across states in the data set provided by the National Inventory of Collateral Consequences of Conviction. We compare incarceration rates, unemployment rates, and labor force participation rates to the number of rules that affect someone with a criminal background. Our results predict that states with more collateral consequences will have higher per-capita imprisonment, higher unemployment, and lower labor force participation rates

Emergent discrete time and quantization: relativistic particle with extradimensions

We study the reparametrization invariant system of a classical relativistic particle moving in (5+1) dimensions, of which two internal ones are compactified to form a torus. A discrete physical time is constructed based on a quasi-local invariant observable. Due to ergodicity, it is simply related to the proper time on average. The external motion in Minkowski space can then be described as a unitary quantum mechanical evolution.Comment: 13 pages, 6 figures; replaced with embedded figures and fixed layou