Magnetotransport Properties and Subband Structure of the Two-Dimensional Electron Gas in the Inversion Layer of Hg1-xCdxTe Bicrystals

The electronic and magnetotransport properties of conduction electrons in the grain boundary interface of p-type Hg1-xCdxTe bicrystals are investigated. The results clearly demonstrate the existence of a two-dimensional degenerate n-type inversion layer in the vicinity of the grain boundary. The observed quantum oscillations of the magnetoresistivity result from a superposition of the Shubnikov-de Haas effect in several occupied electric subbands. The occupation of higher subbands is presumable depending on the total carrier density ns of the inversion layer. Electron densities, subband energies, and effective masses of these electric subbands in samples with different total densities are determined. The effective masses of lower subbands are markedly different from the band edge values of the bulk material, their values decrease with decreasing electron density and converging to the bulk values at lower densities. This agrees with predictions of the triangular potential well model and a pronounced nonparabolicity of the energy bands in Hg1-xCdxTe. At high magnetic fields (B > 10 T) it is experimentally verified that the Hall resistivity xy is quantized into integer multiplies of h/e2

CON-COUR study: Interferential therapy in the treatment of chronic constipation in adults: study protocol for a randomized controlled trial

International audienceBackground: The prevalence of chronic constipation is about 15 % in Western countries with a significant impact on quality of life and health care costs. The first-line therapy, based on medical treatment combined with laxatives and dietary rules, is often disappointing. Interferential therapy is a new treatment that has demonstrated its efficiency in the treatment of chronic constipation in children and encouraging results in adults. The primary objective of this study is to assess the efficacy of interferential therapy during 8 weeks in adult patients. The secondary objectives are to assess this new and noninvasive therapy in terms of persistence of the clinical efficacy, colonic transit time, ano-rectal manometry, patient satisfaction and quality of life (QoL), and tolerance. Methods/ Design: Design: multicenter, prospective, randomized, placebo-controlled, double blind, two-parallel groups study. Setting: nine French adult gastroenterology centers. Inclusion criteria: adult patients with a history of chronic constipation refractory to medical treatment for at least 3 months. Treatment groups: (1) interferential-experimental group (effective stimulation); (2) placebo-control group (sham stimulation). Randomization: 1:1 allocation ratio. Evaluation times: inclusion (T0, randomization), baseline assessment (T1), start of stimulation (T2), intermediary assessment (T3, 4 weeks), end of stimulation (T4, 8 weeks), follow-up (T5 and T6, 1- and 6-month). Endpoints: (1) primary: short-term efficacy at T4 (treatment response defined as three or more spontaneous, complete bowel movements per week); (2) secondary: efficacy at T5 and T6, symptoms (Patient Assessment of Constipation Symptoms questionnaire), colonic transit time, anorectal manometry, patient satisfaction (analogical visual scale), patient QoL (Patient Assessment of Constipation Quality of Life Questionnaire), side/unexpected effects. Sample size: 200 individuals to obtain 80 % power to detect a 20 % difference in treatment response at T4 between the two groups (15 % of lost to follow-up patients expected). Discussion: The randomized, double-blind, placebo-controlled design is the most appropriate to demonstrate the efficacy of a new experimental therapeutic (Evidence-Based Medicine Working Group classification). National and international recommendations could be updated based on the findings of this study

Management Department History

This departmental history was written on the occasion of the UND Quasquicentennial in 2008.https://commons.und.edu/departmental-histories/1071/thumbnail.jp

Mechanical properties of Michigan Basin\u27s gypsum before and after saturation

The stability analysis of an abandoned underground gypsum mine requires the determination of the mine pillar\u27s strength. This is especially important for flooded abandoned mines where the gypsum pillars become saturated and are subjected to dissolution after flooding. Further, mine pillars are subjected to blast vibrations that generate some level of macro- and micro-fracturing. Testing samples of gypsum must, therefore, simulate these conditions as close as possible. In this research, the strength of gypsum is investigated in an as-received saturated condition using uniaxial compressive strength (UCS), Brazilian tensile strength (BTS) and point load index (PLI) tests. The scale effect was investigated and new correlations were derived to describe the effect of sample size on both UCS and BTS under dry and saturated conditions. Effects of blasting on these parameters were observed and the importance of choosing the proper samples was discussed. Finally, correlations were derived for both compressive and tensile strengths under dry and saturated conditions from the PLI test results, which are commonly used as a simple substitute for the indirect determination of UCS and BTS

Building Collapse Due to Shallow Trench Excavation

A building collapse is investigated in which a shallow trench, excavated along the length of the building, resulted in the building\u27s collapse. An investigation indicated that the trench had been excavated within 1 ft (0.3 m) of the foundation and that the foundation had been constructed on approximately 7 ft (2.1 m) of soft silty clay with the bottom portion of this soil highly saturated. The bearing capacity of the foundation, prior to excavation, was estimated to have a safety factor as low as 1.5. As a result of the proximity of the trench to the foundation and the soft soils, the trench collapsed soon after excavation. It is believed that the lower portion of the soil flowed into the trench causing a loss of bearing capacity. An understanding of the geologic setting of the foundation soils, coupled with soils information from the USDA\u27s Soil Conservation Service indicated the hazards of excavating in this soil

Lockout At American Crystal Sugar

As a June 23, 2012, vote neared, union workers at American Crystal Sugar were deciding whether the time had come for them to approve the contract offer by the company. Workers continued to staff picket lines at factory entrances, although enthusiasm for consistently staffing the picket line was waning (Lee 2012(1)). Replacement workers had operated the factories for nine months, successfully processing the 2011 sugar beet harvest. The company reported that although there had been some minor problems, all plants were running at nearly full capacity without the union workers. Company leaders indicated they were “attempting to adjust what they consider an archaic labor contract with newer standards that are competitive with other union rates” (Porter, 2012). The union had consistently been voting down the company’s contract offers for almost a year. Workers stated they were standing firm to protect their jobs, salaries, benefits, and promotion opportunities, and were not willing to give away “rights” they had been fighting for the past 50 years (Kolpack, 2011). Yet, many union workers knew that their bargaining power had been significantly eroded by the company’s ability to operate with non-union replacement workers

Neuromodulation and the role of electrodiagnostic techniques

Electrodiagnostic techniques have been utilized in surgery since the early 1960s. These techniques have been primarily used in neurosurgery; however, with the introduction of neuromodulation for voiding dysfunction, these techniques have now found their way into the field of female pelvic medicine. This article will review techniques applicable to evaluate pelvic floor function as it relates to neuromodulation. It will also review the literature describing how these techniques are used to help determine appropriate candidates as well as improve surgical outcomes. A PubMed search was conducted using the terms neuromodulation, Interstim, electrodiagnosis, electrodiagnostic techniques, electromyography with limits to the pelvic floor, and voiding dysfunction. Eight articles and three abstracts were found that directly related to the use of electrodiagnostic techniques as they apply to neuromodulation. Electrodiagnostic techniques may play a role in helping predict appropriate candidates for neuromodulation as well as improve surgical outcomes