Performance limitations of GaAs/AlGaAs infrared superlattices

The performance of the GaAs/AlGaAs superlattice as an infrared detecting material is modeled as a function of temperature for two cutoff wavelengths, namely, 8.3 and 10.0 µm. The results are compared with HgCdTe, the present industry standard material for infrared systems. The limiting performance of the GaAs/AlGaAs materials system is found to be orders of magnitude below that of HgCdTe for any specific cutoff wavelength and operating temperature

Low crater frequencies and low model ages in lunar maria: Recent endogenic activity or degradation effects?

Recently a number of studies have identified small lunar geologic structures to be <100 Ma in age using standard remote sensing techniques. Here we present new crater size frequency distributions (CSFD) and model ages using craters D> 10 m for 5 small target units: 1 Irregular Mare Patch (IMP) in Mare Nubium and 4 regions located on lunar wrinkle ridges in Mare Humorum. For comparison we also date another IMP found in a recent study in Mare Tranquillitatis (Braden et al., 2014). Absolute model age derivation corresponds to 46$\pm$5 Ma and 22$\pm$1 Ma for Nubium and Sosigenes IMP. We show that for IMPs and in nearby control mare regions similar production-like cumulative log-log SFD slopes of -3 are observed. In contrast control mare regions in Mare Humorum exhibit shallower equilibrium slopes from -1.83 to -2. 3 out of 4 wrinkle ridges appear to be in equilibrium but with crater life times lower than on the corresponding maria. Low crater frequencies on one wrinkle ridge result in an age of 8.6$\pm$1 Ma. This study region contains 80% fresh craters which suggests that the crater population is still in production indicative of a recent resurfacing event

Physical Quality of South Dakota Wheat

The producer selling wheat to the country elevator or shipper does so on the basis of physical quality of the grain. Increased wheat production throughout the world has stiffened competition in the wheat market and all wheat producers are realizing the need for keeping a closer watch on quality. A study of the physical quality of hard red winter and hard red spring wheat in South Dakota began in 1963. Each summer for 5 years, samples were taken from trucks at country elevators to ascertain the quality of wheat being delivered by South Dakota producers. The samples were studied and graded according to the Official Grain Grading Standards of the United States Department of Agriculture

Severe gingival recession and early loss of teeth in a child with chronic graft versus host disease: a case report

Graft versus host disease (GVHD) oceurs after a hematopoietic stem cell transplantation (HSCT) when the donors immune system rejects the recipienfs body, leading to significant morbidity and mortality. Increased numbers of chronic GVHD (c-GVHD) patients are likely to be seen by dental professionals because of the advances made in transplantation. The oral cavity may be the primary or the only site of c-GVHD and may have persistent lesions after resolution has oceurred in other areas. Approximately 80% of patients with extensive c-GVHD present some type of oral involvement, including xerostomia, oral pain and lesions. Dental and oral care can be challenging for these patients. This paper discusses the manifestations and treatment of oral c-GVHD and presents the case history of a 15-month-old girl who developed severe oral GVHD with an unusual periodontal presentation and early loss of primary teeth.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72216/1/j.1754-4505.2007.tb00329.x.pd

Factors Influencing Candidatesâ Choice of a Pediatric Dental Residency Program

The goal of this study was to identify the factors and program characteristics that influenced the program ranking decisions of applicants to pediatric dentistry residency programs. A questionnaire was sent to the firstâ year resident class in 2005 with a response rate of 69.2 percent (n=260). Approximately 55 percent were female (104/180) and 61 percent were nonâ Hisâ panic white (110/180). The respondents reported that they applied to an average of nine programs, of which five were ranked. Most applicants were interested in a program that had a hospital component with a duration of two years. A program’s ability to prepare the resident for an academic career was a minimal influence for 48.6 percent (87/179), and 57.5 percent (103/179) were not interested in a master’s or Ph.D. degree. Factors associated with program ranking included modern clinical facilities, high ratio of dental assistants and faculty to residents, availability of assistants for sedation and general anesthesia cases, availability of a salary or stipend, and amount of clinical experience. Important nonâ clinical factors included hospitality during the interview, geographic location, and perceived reputation of the program. Opportunity to speak with the current residents in private, observing the interaction between residents and faculty, and touring the facilities were also highly considered. These findings may help program directors tailor their interviews and programs to suit the needs of applicants.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153649/1/jddj002203372007719tb04384x.pd

Wheat Quality and Yield. . . Spring versus Winter

Recent introduction of more winter hardy varieties of winter wheat coupled with new ideas in cultural practices have greatly improved the potential of winter wheat in South Dakota. Basic to the decision of whether to grow spring or winter wheat are questions of quality, protein and yield. An analysis of the quality of the 1967 South Dakota wheat crop was made from samples taken in 11 counties where both winter and spring wheat were produced. The counties were: Butte, Faulk, Haakon, Hand, Hughes, Hyde, Perkins, Potter, Spink, Stanley and Sully

LGBT Coverage in U.S. Dental Schools and Dental Hygiene Programs: Results of a National Survey

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153556/1/jddj0022033720168012tb06231x.pd

Factors Influencing Pediatric Dental Program Directorsâ Selection of Residents and Demographics of Current Directors

The primary goal of this study was to examine the criteria that influence rankings of candidates by advanced education program directors in pediatric dentistry. Secondary objectives were to obtain information on the resident selection process and to explore demographics of current program directors. A survey was sent in 2005 to all sixtyâ three program directors of pediatric dentistry residency programs accredited within the United States for the graduating class of 2007. The survey had a response rate of almost 78 percent (49/63). Respondents were requested to rank the importance of eleven factors that are typically included in the selection criteria for pediatric dentistry residents. Factors were rated on a scale of critical, very important, fairly important, somewhat important, and not important. The four highest ranked criteria by program directors were the following, in order: National Board scores, dental school clinical grades, class rank, and grade point average (GPA). Other factors ranked in descending order of perceived importance were the following: dental school basic science grades, experience in pediatric dentistry, extracurricular activities, completion of a general practice residency or advanced education in general dentistry program, the application essay, a publication or professional presentation, and private practice experience. All directors ranked personal interviews as very important to critical. Letters of recommendation from a pediatric dentistry department chairperson or faculty member were viewed more favorably than letters from dental school deans and nonâ pediatric dentistry faculty. Fiftyâ seven percent of the directors responding (28/49) were male, and 81 percent (40/49) were white, nonâ Hispanic. Fiftyâ nine percent of the directors (29/49) graduated from a residency program over twenty years ago, with 39 percent (19/49) having been a director for less than five years.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153594/1/jddj002203372009733tb04706x.pd