A single-electron inverter

A single-electron inverter was fabricated that switches from a high output to a low output when a fraction of an electron is added to the input. For the proper operation of the inverter, the two single-electron transistors that make up the inverter must exhibit voltage gain. Voltage gain was achieved by fabricating a combination of parallel-plate gate capacitors and small tunnel junctions in a two-layer circuit. Voltage gain of 2.6 was attained at 25 mK and remained larger than one for temperatures up to 140 mK. The temperature dependence of the gain agrees with the orthodox theory of single-electron tunneling.Comment: 3 pages, 4 figures (1 color), to be published in Appl. Phys. Let

Negative differential resistance due to single-electron switching

We present the multilevel fabrication and measurement of a Coulomb-blockade device displaying tunable negative differential resistance (NDR). Applications for devices displaying NDR include amplification, logic, and memory circuits. Our device consists of two Al/Al$_{x}$O$_{y}$ islands that are strongly coupled by an overlap capacitor. Our measurements agree excellently with a model based on the orthodox theory of single-electron transport.Comment: 3 pages, 3 figures; submitted to AP

High field CdS detector for infrared radiation

New and highly sensitive method of detecting infrared irradiation makes possible solid state infrared detector which is more sensitive near room temperature than usual photoconductive low band gap semiconductor devices. Reconfiguration of high field domains in cadmium sulphide crystals provides basis for discovery

High field CdS detector for infrared radiation

An infrared radiation detector including a cadmium sulfide platelet having a cathode formed on one of its ends and an anode formed on its other end is presented. The platelet is suitably doped such that stationary high-field domains are formed adjacent the cathode when based in the negative differential conductivity region. A negative potential is applied to the cathode such that a high-field domain is formed adjacent to the cathode. A potential measuring probe is located between the cathode and the anode at the edge of the high-field domain and means are provided for measuring the potential at the probe whereby this measurement is indicative of the infrared radiation striking the platelet

Anxious childhood attachment predicts childlessness in later life

The objective of this study was to test the hypothesis that childhood attachment predicts whether a person has children in later life. Although being a parent is considered a typical part of the human life cycle in most parts of the world, childlessness has increased substantially in recent decades in developed parts of the world. It is possible that insecure childhood attachment has contributed to this phenomenon, but this hypothesis has been relatively little explored. This study is a cross-sectional survey of 394 men and women aged over 50 years old, stratified by geographical UK region from a research panel, and analysed using hierarchical logistic regression. Validated measures of childhood attachment and other psychological and demographic factors were used. The main finding was that, independent of the impact of other variables (age, sex, education level, marital status, life stress, healthrelated quality of life, mental positivity, and avoidant attachment style), people who were childless were significantly more likely to have developed an anxious attachment to their primary caregiver in childhood. This study is the first to demonstrate the significance of anxious childhood attachment as a predictor of producing children in one’s lifetime

Stress Fractures of the Elbow in the Throwing Athlete: A Systematic Review.

Background: Stress fractures of the elbow are rare in throwing athletes and present a challenge from both a management and rehabilitation perspective. Although the incidence of stress fractures of the elbow is increasing, there is a lack of data in the literature focused on throwers. Purpose: To evaluate studies regarding the management and outcomes of stress fractures of the elbow in throwing athletes. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was conducted by searching the Scopus, PubMed, and Cochrane Library electronic databases to identify studies reporting on the management and outcomes of stress fractures in overhead-throwing athletes. Management data included nonoperative and operative modalities, and outcome data included return to play, encompassing the timing and level of activity. Studies were excluded if the stress fracture of the elbow was not a result of a sport injury attributed to throwing or if the study failed to report whether an athlete returned to play. Results: Fourteen studies met the inclusion criteria and were included in this analysis. There were 52 patients in total (50 male, 2 female) with a mean age of 19.7 years (range, 13-29.1 years). The olecranon was the most common location of the stress fracture (51 patients; 98.1%), followed by the distal humerus (1 patient; 1.9%). The majority of patients (n = 40; 76.9%) were treated operatively. Of the 40 patients who were treated surgically, 14 (35.0%) underwent a period of conservative treatment preoperatively that ultimately failed because of persistent nonunion or continued elbow pain. A total of 50 patients (96.2%) returned to sport either at or above their preinjury level. Of the 2 patients (3.8%) who did not return to sport, 1 did not return because of continued elbow pain postoperatively, and the other was lost to follow-up. Complications occurred in 9 patients (17.3%), all of whom were treated surgically. Conclusion: On the basis of this systematic review, the majority of elbow stress fractures were treated operatively and approximately one-third after a period of failed nonoperative management. The return-to-sport rate was high. Further, higher level studies are needed to optimize management and return-to-sport rates in this population

Research notes: Sterility mutants in soybeans

In 1975 we selected green, partially sterile plants in farmers\u27 fields when the normal plants had dropped their leaves and were ready for harvest . Seeds were harvested from the off-type plants and planted in the greenhouse (1975-76). The resulting plants which we called F1\u27s were nonnal

Unified Framework for Correlations in Terms of Local Quantum Observables

We provide a unified framework for nonsignalling quantum and classical multipartite correlations, allowing all to be written as the trace of some local (quantum) measurements multiplied by an operator. The properties of this operator define the corresponding set of correlations.We then show that if the theory is such that all local quantum measurements are possible, one obtains the correlations corresponding to the extension of Gleason's Theorem to multipartite systems. Such correlations coincide with the quantum ones for one and two parties, but we prove the existence of a gap for three or more parties.Comment: 4 pages, final versio

Gaps in Adolescent Tobacco Prevention and Counseling in Vermont

Introduction. Tobacco use remains the leading cause of preventable death in Vermont. While the Vermont Blueprint for Health includes compensation for adult tobacco counseling, it includes no specific mention of pediatric populations. Research questions: To what extent are tobacco assessment and cessation efforts occurring in the primary care setting with pediatric patients? What factors influence their practices?Methods. A 12-question electronic survey, modeled on an American Academy of Pediatrics survey, was distributed to primary care providers throughout Vermont; through the UVM departments of pediatrics, family medicine, the Vermont Medical Society and the Vermont Area Health Education Center. We received 70 completed surveys.Results. 70% of the surveyed primary care providers begin tobacco counseling at the age recommended (11 years) by the Vermont Department of Health. Only 45.71% of providers are confident in their understanding of the recommendations for adolescent health screening written in the Blueprint for Health. Additionally, only 67.1% of the providers expressed confidence in their ability to provide guidance regarding the harmful effects of E-cigarettes, compared to 92.8% feeling confident regarding conventional cigarettes. 70% of providers listed time restraints as a significant factor in their decision not to counsel adolescents on tobacco use.Discussion. The Blueprint for Health is a guiding document for provider practices that is not well understood and does not specifically include pediatric tobacco prevention. In an environment where youth E-cigarette use is rising, especially among adolescents, it is especially critical that physicians are confident in their counseling practices.https://scholarworks.uvm.edu/comphp_gallery/1237/thumbnail.jp