Holographic data storage in a DX-center material

We report on the optical storage of digital data in a semiconductor sample containing DX centers. The diffraction efficiency and the bit-error-rate performance of multiplexed data images are shown to agree well with a simple model of the material. Uniform storage without an exposure schedule is demonstrated. The volume sensitivity is found to be ~10^3 times that of LiNBO3:Fe. The importance of coherent addition of scattered light with diffracted light in holographic data storage is discussed

Dirac Cat States in Relativistic Landau Levels

We show that a relativistic version of Schrodinger cat states, here called Dirac cat states, can be built in relativistic Landau levels when an external magnetic field couples to a relativistic spin 1/2 charged particle. Under suitable initial conditions, the associated Dirac equation produces unitarily Dirac cat states involving the orbital quanta of the particle in a well defined mesoscopic regime. We demonstrate that the proposed Dirac cat states have a purely relativistic origin and cease to exist in the non-relativistic limit. In this manner, we expect to open relativistic quantum mechanics to the rich structures of quantum optics and quantum information.Comment: Revtex4, color figures, submitted for publicatio

Australian SMEs waste to landfill

Landfill waste has a negative impact on the environment and small and medium sized enterprises (SMEs) are believed to be significant contributors. There is little government or scholarly research, however, quantifying the collective volume of waste SMEs send to landfill. Where studies do exist they measure total volumes (landfill and recycling combined) and/or do not distinguish between specific waste streams (e.g. wood) and subcategories (e.g. dust). This paper contributes to knowledge by giving insight into the collective volume of waste of 404 SMEs, reconceptualising SME waste into subcategories and by measuring landfill volumes. It presents findings from these 404 Australian SMEs which found that, in descending order, cardboard, paper, plastic wrap, wood dust and particleboard were the subcategories these SMEs sent to landfill in the greatest volumes. It also argues that this reconceptualisation, and associated data collection protocols, have the potential to enable scholars and policy makers to determine the waste subcategories to which SMEs contribute most, formulate targeted interventions and research or evaluate environmental outcomes. © 2014 © 2014 Environment Institute of Australia and New Zealand Inc

Computer recommendations for an automatic approach and landing system for V/STOL aircraft. Volume 2 - Equations

Automatic approach and landing system for V/STOL aircraf

Waiting for Godot or sorting it now?

Postgraduate business education has become a very important financial stream for most tertiary institutions. However, what is becoming increasingly evident is that the assumption of good or even adequate academic competence, based on IELTS scores, is incorrect and that in reality many international students struggle to meet the academic standards and expectations of the overseas universities. This manifests itself in many ways; ultimately students fail units and have negative learning experiences. At best they reflect competencies of surface learners rather than those of deep learners. This paper reports on interim results of a pilot study that embedded an academic skills component into an introductory management unit in a MBA program. Based on the students’ plagiarism scores, the results to date demonstrate a positive outcome of the intervention. The students were found to have a significantly lower rate of plagiarism compared with a previous cohort. The pilot study highlights the need for more personal face-to-face help rather than impersonal cyber help and that when it comes to student learning, the ever increasing use of technology is misguided and over used as the salve for all problems

732-1 An Institutional Experience with Second and Third Stage Palliative Procedures for Hypoplastic Left Heart Syndrome: The Impact of the Bidirectional Cavopulmonary Shunt

We reviewed 71 consecutive pts who underwent stage II and III operations following stage I palliation for hypoplastic left heart syndrome (HLHS) at our institution since 1983. 6 surgeons participated in the care of these pts. Follow-up is 97% complete. We examined 17 potential risk factors for mortality, including preoperative anatomic and physiologic factors, and procedural features of the stage II operation. Multivariate analysis revealed that the only significant risk factor for stage II mortality was the performance of a non-fenestrated completion Fontan procedure (p<0.001). There were 9 hospital deaths (69%) in the 13 pts undergoing the Fontan procedure at stage II. In contrast, 49 pts underwent bidirectional cavopulmonary shunting (47) or hemi-Fontan procedure(2) as an intermediate step to the Fontan procedure with 4 (8%) early deaths. The first bidirectional cavopulmonary shunt was performed in this population in 1988. Median age at this stage II procedure was 8.4 months. Surgical augmentation of the pulmonary arteries was performed in 18 (37%) pts at the time of stage II surgery and was not associated with increased operative risk. Also, HLHS anatomic subtype was not a risk factor for stage II mortality or pre-stage III attrition. There have been 2 (4%) intermediate deaths prior to the performance of a stage III procedure, which at our institution is the fenestrated Fontan procedure. This has been performed in 25 pts at a median age of 30 months with 1 early death and no mortality at a median follow-up of 22 months. There are presently 34 HLHS pts who have modified Fontan anatomy following a course of surgical palliation performed entirely at this institution. Follow-up in this group ranges up to 92 months, with a median of 28 months. 33 of these patients are NYHA class 1 or 2.2 pts have required pacemaker implantation, but there have otherwise been no surgical reinterventions in pts who have completed palliation. We conclude that the incorporation of the bidirectional cavopulmonary shunt into a course of surgical palliation for HLHS has dramatically reduced mortality in this challenging group of pts, allowing them to undergo the modified fenestrated Fontan procedure with low operative mortality and good intermediate outcome

Northern Bobwhite Response to Control of Red Imported Fire Ants in the Gulf Coast Prairie of Texas

The population decline of northern bobwhite (Colinus virginianus; hereafter, bobwhite) on the Texas Gulf Coast Prairie, USA is largely attributed to habitat loss. However, red imported fire ants (Solenopsis invicta) occur throughout the region and are considered a possible contributing factor to the bobwhite decline. The objectives of our study were to determine the influence of red imported fire ants on bobwhites by comparing bobwhite nest success, survival, and density between sites treated with fire ant bait (treatment) and reference (control) sites. Our study was conducted on 3 private ranches in Goliad and Refugio counties, Texas. Each ranch contained 2 paired experimental units that consisted of a treatment and control site (500 ha each). The treatment sites received an aerial application of fire ant bait (Extinguish® Plus) during April 2018, whereas the control sites were not treated. We estimated mound density by counting fire ant mounds using distance sampling. We used radio-telemetry to monitor bobwhite nest success and survival, and we estimated bobwhite densities using distance sampling via helicopter surveys. Fire ant mound density decreased through time on both treatment and control sites. However, fire ant mound density was lower on treatment sites than control sites, indicating the insecticide was effective at decreasing fire ant mound density. Bobwhite survival, nest success, and density did not statistically differ between control and treated sites either pre-treatment (2017) or post-treatment (2018), but survival and nest success metrics were numerically higher in treated units. Bobwhite survival remained relatively stable in the treatment units 4 weeks after application but decreased in the control units. Following treatment, apparent nest success in the treated units increased by 37.4% while nest success in the control units decreased by 35.2%. Bobwhite populations were low in this ecoregion, which influenced our ability to trap and monitor many bobwhites or monitor many nests. In addition, it may be possible that repeated, annual treatments for fire ants are necessary for a benefit to accrue and be observed in bobwhites. Our results indicate that there may be potential benefits to bobwhites from fire ant reduction that deserve further research attention

Trend Identification in Twentieth-Century U.S. Snowfall: The Challenges

There is an increasing interest in examining long-term trends in measures of snow climatology. An examination of the U.S. daily snowfall records for 1900–2004 revealed numerous apparent inconsistencies. For example, long-term snowfall trends among neighboring lake-effect stations differ greatly from insignificant to +100% century -1. Internal inconsistencies in the snow records, such as a lack of upward trends in maximum seasonal snow depth at stations with large upward trends in snowfall, point to inhomogeneities. Nationwide, the frequency of daily observations with a 10:1 snowfall-to-liquid-equivalent ratio declined from 30% in the 1930s to a current value of around 10%, a change that is clearly due to observational practice. There then must be biases in cold-season liquid-equivalent precipitation, or snowfall, or both. An empirical adjustment of snow-event, liquid-equivalent precipitation indicates that the potential biases can be statistically significant. Examples from this study show that there are nonclimatic issues that complicate the identification of and significantly change the trends in snow variables. Thus, great care should be taken in interpretation of time series of snow-related variables from the Cooperative Observer Program (COOP) network. Furthermore, full documentation of optional practices should be required of network observers so that future users of these data can properly account for such practices

Trends in Twentieth-Century U.S. Extreme Snowfall Seasons

Temporal variability in the occurrence of the most extreme snowfall years, both those with abundant snowfall amounts and those lacking snowfall, was examined using a set of 440 quality-controlled, homogenous U.S. snowfall records. The frequencies with which winter-centered annual snowfall totals exceeded the 90th and 10th percentile thresholds at individual stations were calculated from 1900–01 to 2006–07 for the conterminous United States, and for 9 standard climate regions. The area-weighted conterminous U.S. results do not show a statistically significant trend in the occurrence of either high or low snowfall years for the 107-yr period, but there are regional trends. Large decreases in the frequency of low-extreme snowfall years in the west north-central and east north-central United States are balanced by large increases in the frequency of low-extreme snowfall years in the Northeast, Southeast, and Northwest. During the latter portion of the period, from 1950–51 to 2006–07, trends are much more consistent, with the United States as a whole and the central and northwest U.S. regions in particular showing significant declines in high-extreme snowfall years, and four regions showing significant increases in the frequency of low-extreme snowfall years (i.e., Northeast, Southeast, south, and Northwest). In almost all regions of the United States, temperature during November–March is more highly correlated than precipitation to the occurrence of extreme snowfall years. El Nin ̃ o events are strongly associated with an increase in low-extreme snowfall years over the United States as a whole, and in the northwest, northeast, and central regions. A reduction in low-extreme snowfall years in the Southwest is also associated with El Nin ̃ o. The impacts of La Nin ̃ a events are strongest in the south and Southeast, favoring fewer high-extreme snowfall years, and, in the case of the south, more low-extreme snowfall years occur. The Northwest also has a significant reduction in the chance of a low-extreme snowfall year during La Nin ̃ a. A combination of trends in temperature in the United States and changes in the frequency of ENSO modes influences the frequency of extreme snowfall years in the United States