4,731 research outputs found
Streamer branching rationalized by conformal mapping techniques
Spontaneous branching of discharge channels is frequently observed, but not
well understood. We recently proposed a new branching mechanism based on
simulations of a simple continuous discharge model in high fields. We here
present analytical results for such streamers in the Lozansky-Firsov limit
where they can be modelled as moving equipotential ionization fronts. This
model can be analyzed by conformal mapping techniques which allow the reduction
of the dynamical problem to finite sets of nonlinear ordinary differential
equations. The solutions illustrate that branching is generic for the intricate
head dynamics of streamers in the Lozansky-Firsov-limit.Comment: 4 pages, 2 figure
Fractional Calculus as a Macroscopic Manifestation of Randomness
We generalize the method of Van Hove so as to deal with the case of
non-ordinary statistical mechanics, that being phenomena with no time-scale
separation. We show that in the case of ordinary statistical mechanics, even if
the adoption of the Van Hove method imposes randomness upon Hamiltonian
dynamics, the resulting statistical process is described using normal calculus
techniques. On the other hand, in the case where there is no time-scale
separation, this generalized version of Van Hove's method not only imposes
randomness upon the microscopic dynamics, but it also transmits randomness to
the macroscopic level. As a result, the correct description of macroscopic
dynamics has to be expressed in terms of the fractional calculus.Comment: 20 pages, 1 figur
Review of \u3cem\u3eThe Mutual Housing Experiment: New Deal Communities for the Urban Middle Class\u3c/em\u3e by Kristin M. Szylvian
Review of \u3cem\u3eThe Federal Design Dilemma: Congress and Intergovernmental Delegation\u3c/em\u3e, by Pamela J. Clouser McCann
Whose Job Is It Anyway? Preparing Arbitrators for Consumer Dispute Resolution Programs
[Excerpt] In many respects, we have entered into a golden era in the evolution and study of conflict resolution. One of the most obvious examples of this new era is the significant growth of conflict resolution programs in institutions of higher education. The purpose of this article is to examine the current state of university and law school conflict resolution programs. We then offer some conclusions and recommendations for addressing what we believe to be the critically important role academia can and should play in training arbitrators.
Our review of academic programs suggests that the array of offerings has grown substantially and includes credit courses, clinics, degree programs, and certificates in conflict resolution. At our own institution, Cornell University, the response by our student body to opportunities for studying conflict resolution has overwhelmed our current capacity to meet their needs and interests
Book Review of \u3cem\u3eFragmented Democracy: Medicaid, Federalism, and Unequal Politics\u3c/em\u3e, By Jamila Michener
Helicobacter pylori infection and gastric dysbiosis: Can probiotics administration be useful to treat this condition?
Helicobacter pylori (Hp) is responsible for one of the most common infections in the world. 'e prevalence exceeds 50% of the
population in developing countries, and approximately one-third of the adults are colonized in North Europe and North America.
It is considered a major pathogenic agent of chronic gastritis, peptic ulcer, atrophic gastritis, gastric cancer, and mucosa-associated
lymphoid tissue lymphoma (MALT). Hp colonization modifies the composition of gastric microbiota that could drive the
development of gastric disorders. Currently, an emerging problem in Hp treatment is represented by the increasing rate of
antimicrobial therapy resistance. In this context, the search for adjuvant agents can be very useful to overcome this issue and
probiotics administration can represent a valid option. The aim of this review is to describe the gastric microbiota changes during
Hp colonization, the mechanisms of action, and a possible role of probiotics in the treatment of this infection
High-frequency cyclicity in the Mediterranean Messinian evaporites: evidence for solar-lunar climate forcing
The deposition of varved sedimentary sequences is usually controlled by
climate conditions. The study of two Late Miocene evaporite successions (one
halite and the other gypsum) consisting of annual varves has been carried out
to reconstruct the paleoclimatic and paleoenvironmental conditions existing
during the acme of the Messinian salinity crisis, ~ 6 Ma, when thick evaporite
deposits accumulated on the floor of the Mediterranean basin. Spectral analyses
of these varved evaporitic successions reveal significant periodicity peaks at
around 3-5, 9, 11-13, 20-27 and 50-100 yr. A comparison with modern
precipitation data in the western Mediterranean shows that during the acme of
the Messinian salinity crisis the climate was not in a permanent evaporitic
stage, but in a dynamic situation where evaporite deposition was controlled by
quasi-periodic climate oscillations with similarity to modern analogs including
Quasi-Biennial Oscillation, El Ni\~no Southern Oscillation, and decadal to
secular lunar- and solar-induced cycles. Particularly we found a significant
quasi-decadal oscillation with a prominent 9-year peak that is commonly found
also in modern temperature records and is present in the contemporary Atlantic
Multidecadal Oscillation (AMO) index and Pacific Decadal Oscillation (PDO)
index. These cyclicities are common to both ancient and modern climate records
because they can be associated with solar and solar-lunar tidal cycles.Comment: 13 pages, 10 figures, 1 Tabl
Reply to Alessia Cimadamore, Marina Scarpelli, Liang Cheng, et al's Letter to the Editor, re: Maria Chiara Sighinolfi, Bernardo Rocco's Words of Wisdom re: EAU Guidelines: Prostate Cancer 2019. Mottet N, van den Bergh RCN, Briers E, et al. https://uroweb.org/guideline/prostate-Cancer/. Eur Urol 2019, 76:871
RE: Renal protective effect of N-acetylcysteine with stepwise ramping voltage against extracorporeal shock wave lithotripsy-induced renal injury: a prospective randomized trial from Desoky et al
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