Short-term outcomes of laparoscopic gastric plication in morbidly obese patients: Importance of postoperative follow-up

Demand for feasible, safe, and preferably low-cost methods of weight reduction is rising every day. The present study reports findings from laparoscopic gastric plication (LGP), which is a new restrictive bariatric technique, combined with a postoperative follow-up program. A 2-year prospective study was performed following LGP in 53 female morbidly obese patients from Gorgan, Iran, with a mean age of 36.3 years and mean body mass index (BMI) of 42.6 kg/m2 (35.3-62.4). Through a four-port approach, the greater omentum and short gastric vessels were transected and the greater curvature was imbricated into the body of the stomach with two rows of nonabsorbable sutures. After surgery, all patients were scheduled to attend a weekly group meeting for behavioral modification and psychotherapy. The mean operative time and hospital stay was 95 min and 72 h, respectively. No intraoperative complications occurred. Mean percentages of excess weight loss (%EWL) were 25.6 %, 54.2 %, 70.2 %, and 74.4 % after 1, 6, 12, and 24 months, respectively. Six patients lost >84 % of their excess weight after 24 months. Patients who did not participate in the group meetings had a lower %EWL after 12 (79.5 % vs. 55.6 %) and 24 months (90 % vs. 43.4 %) compared with the patients who regularly participated in the group meetings (P < 0.005). LGP is a feasible, safe, and effective surgical method for weight loss for at least 24 months when performed on morbidly obese patients. Postoperative group meetings (POGM) for psychotherapy and behavioral modification helped patients to achieve better results. © 2012 Springer Science + Business Media, LLC

Tunneling Ionization Rates from Arbitrary Potential Wells

We present a practical numerical technique for calculating tunneling ionization rates from arbitrary 1-D potential wells in the presence of a linear external potential by determining the widths of the resonances in the spectral density, rho(E), adiabatically connected to the field-free bound states. While this technique applies to more general external potentials, we focus on the ionization of electrons from atoms and molecules by DC electric fields, as this has an important and immediate impact on the understanding of the multiphoton ionization of molecules in strong laser fields.Comment: 13 pages, 7 figures, LaTe

Enhancement of in vitro production of volatile organic compounds by shoot differentiation in Artemisia spicigera

Callus initiation, shoot formation and plant regeneration were established for Artemisia spicigera, a traditional medicinal plant growing in Armenia, Middle-Anatolia and Iran, and pro- ducing valuable volatile organic compounds (VOCs) that are mostly represented by monoterpe- noids. Optimal callus initiation and shoot production were obtained by culture of hypocotyl and cotyledon explants on MS medium comprising 0.5 mg L−1 naphthalene acetic acid (NAA) and 0.5 mg L−1 6-benzyladenine (BA). Consequently, the shoots were transferred onto the MS media sup- plemented with 1 mg L−1 of indole-3-butyric acid (IBA) or 1 mg L−1 of NAA. Both types of auxin induced root formation on the shoots and the resulting plantlets were successfully grown in pots. The production of VOCs in callus tissues and regenerated plantlets was studied by gas chroma- tography–mass spectrometry (GC-MS) analysis. Although the potential of undifferentiated callus to produce VOCs was very low, an increased content of bioactive volatile components was ob- served at the beginning of shoot primordia differentiation. Intriguingly, the volatiles obtained from in vitro plantlets showed quantitative and qualitative variation depending on the type of auxins used for the rooting process. The acquired quantities based on total ion current (TIC) showed that the regenerated plantlets using 1 mg L−1 NAA produced higher amounts of oxygenated monoter- penes such as camphor (30.29%), cis-thujone (7.07%), and 1,8-cineole (6.71%) and sesquiterpene derivatives, namely germacrene D (8.75%), bicyclogermacrene (4.0%) and spathulenol (1.49%) compared with the intact plant. According to these findings, in vitro generation of volatile organic compounds in A. spicigera depends on the developmental stages of tissues and may enhance with the formation of shoot primordia and regeneration of plantlets

Many-electron tunneling in atoms

A theoretical derivation is given for the formula describing N-electron ionization of atom by a dc field and laser radiation in tunneling regime. Numerical examples are presented for noble gases atoms.Comment: 11 pages, 1 EPS figure, submitted to JETP (Jan 99

Terahertz control of air lasing

The coherent emission from ionized nitrogen molecules is of interest for remote sensing and astronomical applications. To initiate the lasing process, we used an intense ultrashort near-infrared (NIR) pulse overlapped with a terahertz (THz) single-cycle pulse. We observed that coherent emission could be seeded and modulated by the amplitude of the THz field, which is the result of a combined effective second-order nonlinear polarization and the nonlinear effects induced by the NIR pump. Our results shed light on the role of intense transient fields in the coherent emission from photoexcited gas molecules

Shapes of leading tunnelling trajectories for single-electron molecular ionization

Based on the geometrical approach to tunnelling by P.D. Hislop and I.M. Sigal [Memoir. AMS 78, No. 399 (1989)], we introduce the concept of a leading tunnelling trajectory. It is then proven that leading tunnelling trajectories for single-active-electron models of molecular tunnelling ionization (i.e., theories where a molecular potential is modelled by a single-electron multi-centre potential) are linear in the case of short range interactions and "almost" linear in the case of long range interactions. The results are presented on both the formal and physically intuitive levels. Physical implications of the obtained results are discussed.Comment: 14 pages, 5 figure

On negative higher-order Kerr effect and filamentation

As a contribution to the ongoing controversy about the role of higher-order Kerr effect (HOKE) in laser filamentation, we first provide thorough details about the protocol that has been employed to infer the HOKE indices from the experiment. Next, we discuss potential sources of artifact in the experimental measurements of these terms and show that neither the value of the observed birefringence, nor its inversion, nor the intensity at which it is observed, appear to be flawed. Furthermore, we argue that, independently on our values, the principle of including HOKE is straightforward. Due to the different temporal and spectral dynamics, the respective efficiency of defocusing by the plasma and by the HOKE is expected to depend substantially on both incident wavelength and pulse duration. The discussion should therefore focus on defining the conditions where each filamentation regime dominates.Comment: 22 pages, 11 figures. Submitted to Laser physics as proceedings of the Laser Physics 2010 conferenc

Orientation dependence of high-order harmonic generation in molecules

Published versio

Train schedule delays leading to overcrowding, injuries and fatalities

Abstract: Rail industry in South Africa is facing a dilemma in connection with trains overcrowding causing injuries and fatalities. This paper emphasized this topic analysis to reach the understanding of the problem to an eventual solution that will benefit both the train user and the operator. One of the priority insights look was at the annual train planned schedule versus the actual state of trains given to run. The overall objective of the paper’s study was to analyze the existing train schedule that is currently in use and whether addressing the needs of the commuter. The paper highlighted that the found-out train planned schedule are not always met due to technical issues. The paper also investigated the number of healthy trains versus the commuter demand per peak, because operationally fit trains are required to avoid service distraction that can lead to overcrowding of trains