An optometric care flow methodolgy for the military

The purpose of this thesis is to design an optometric clinical system for the military to accommodate the increased needs of the active duty dependents, retirees and their dependents. Many factors were considered that affect the delivery of optometric care in the military. These factors include ancillary personnel, space needs, manpower needs, automated refractors, no shows, appointment system, and a screening program. The methodology to be incorporated is the algorithms in the appointment system, placement of the patient into the proper appointment slot, use of a screening clinic, and clinical flow diagrams for the delivery of optometric care. An increase of 20 to 30 percent in the number of patients seen is projected from the use of the new clinical system. Because few middle grade optometry officers have had any formal management training in running the optometry clinic, or dealing with people a management guideline is included. The management style chosen is participative management. This style of management was chosen because of the type of service delivered by the optometry clinic. Recommendations were made on clinical needs and management training of middle grade optometry officers

An estimate of the global impact of commercial aviation noise

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 67-72).This study estimates the impacts of commercial aviation noise at 181 airports around the world. These airports are located in 38 countries plus Taiwan, with 95 of the airports located in the United States. They are part of the 190 Shell 1 airports in the FAA's Model for Assessing Global Exposure to the Noise of Transport Aircraft (MAGENTA), which comprise an estimated 91% of total global aviation noise exposure [FAA 2008]. The model calculates both physical and monetary impacts of aviation noise. The physical metrics are the number of people exposed to 55 dB or more noise, and the number of people highly annoyed. The model uses a noise depreciation index developed from hedonic pricing studies of housing transactions to monetize the effects on property owners in terms of housing value loss and rent changes. Due to data collection difficulties the impacts are only approximately consistent chronologically. Population data are from the years 2000 and 2001 depending on the country, while house prices and rents are 2006 estimates, and noise levels are for the year 2005. Based on there data, we calculated that around the 181 airports more than 14 million people are exposed to at least 55 dB of commercial aviation noise. Of these individuals, approximately 2.3 million are highly annoyed. We found that the noise resulted in a total of $21 billion of housing value depreciation, which is equivalent to about$1.1 billion per year using a 30-year life of the house and a 3% discount rate, and an additional $800 million of lost rent each year. The impacts are spread over all parts of the world. Although most of the airports included in this study are located in the US and Europe, each continent with an airport in the study had airports with greater than$100 million in housing value loss and greater than 200,000 exposed people.(cont.) Furthermore, North America, Europe, and Asia each had examples of airports with an estimated $80 million in annualized housing value loss ($1 billion total), 400,000 people exposed to 55 dB, and $25 million in yearly lost rent. We also examined potential changes to these impacts in the future for a scenario with no technological or operational advances to reduce noise (with the exception of retirement of older aircraft in the fleet). Based on an assumption of 2-3% annual growth rates in operations at these airports between 2005 and 2035 with no noise-technology improvements, we found that the undiscounted housing value and rent loss could approximately double by 2035 while the population exposed to 55 dB and highly annoyed could increase by about 70%. These results demonstrate the potential gains from further advances in aircraft technology and operations to mitigate community noise.by Christopher KIsh.S.M

Mapping Guaranteed Positive Secret Key Rates for Continuous Variable Quantum Key Distribution

Continuous variable quantum key distribution (CVQKD) is the sharing of secret keys between different parties using the continuous amplitude and phase quadratures of light. There are many protocols in which different modulation schemes are used to implement CVQKD. However, there has been no tool for comparison between different CVQKD protocols to determine the optimal protocol for varying channels while simultaneously taking into account the effects of different parameters. Here, a comparison tool has been developed to map regions of positive secret key rate (SKR), given a channel's transmittance and excess noise, where a user's modulation can be adjusted to guarantee a positive SKR in an arbitrary environment. The method has been developed for discrete modulated CVQKD (DM-CVQKD) protocols but can be extended to other current and future protocols and security proofs.Comment: 15 pages, 9 figure

In My View

BACKGROUND CONTEXT: Prior studies by our group have shown that nicotine delivered via a transdermal nicotine patch significantly enhanced posterior spinal fusion rates in rabbits. This runs contrary to previously published studies by other groups in which nicotine administration decreased fusion rates. Hence, there may be a dose-dependent effect of nicotine on posterior spinal fusion outcomes

Delayed maintenance modelling considering speed restriction for a railway section

The deterioration of track geometry depends on several factors of which the speed of the train is one. Imposing a speed restriction can slow down the track deterioration and allows a longer survival time before a serious condition is achieved. Preventive maintenance delays can be authorized during the survival time. However, speed restrictions also reduce the system throughput. On the other hand, a longer interval between preventive maintenance activities has a lower maintenance action cost and it also enables grouping the maintenance activities to save set-up costs as well as system down time. If the repair delay is too long, it may cause unacceptable conditions on the track and lead to higher maintenance costs and accidents. Therefore, it is interesting to assess the effect of a speed restriction on the delayed maintenance strategies for a railway track section. We want to solve a maintenance optimization problem to find the optimal tuning of the maintenance delay time and imposition of a speed restriction. To this aim, a delayed maintenance model is developed, in which track deterioration depends on the train speed and the number of passing trains. The model is used to determine an optimal speed restriction strategy and a preventive repair delay for the optimization of the system benefit and unavailability. Coloured Petri Nets (CPN) are adopted to model the maintenance and operation of the railway track section. The CPN model describes the gradual track deterioration as a stochastic process. Different speed restriction policies and maintenance delay strategies are modelled and activated by the observed component states. Monte Carlo simulations are carried out to estimate the maintenance cost, the system benefit and the system downtime under different policies. Numerical results show the maintenance decision variable trade-off

Lifetime Prevalence of Mental Disorders in Lebanon: First Onset, Treatment, and Exposure to War

In a survey of 2,857 adults in Lebanon, Elie Karam and colleagues found a lifetime prevalence of any DSM-IV psychiatric disorder of 25.8%

Schistosomiasis transmission at high altitude crater lakes in Western Uganda

<p>Abstract</p> <p>Background</p> <p>Contrary to previous reports which indicated no transmission of schistosomiasis at altitude >1,400 m above sea level in Uganda, in this study it has been established that schistosomiasis transmission can take place at an altitude range of 1487–1682 m above sea level in western Uganda.</p> <p>Methods</p> <p>An epidemiological survey of intestinal schistosomiasis was carried out in school children staying around 13 high altitude crater lakes in Western Uganda. Stool samples were collected and then processed with the Kato-Katz technique using 42 mg templates. Thereafter schistosome eggs were counted under a microscope and eggs per gram (epg) of stool calculated. A semi-structured questionnaire was used to obtain demographic data and information on risk factors.</p> <p>Results</p> <p>36.7% of the pupils studied used crater lakes as the main source of domestic water and the crater lakes studied were at altitude ranging from 1487–1682 m above sea level. 84.6% of the crater lakes studied were infective with over 50% of the users infected.</p> <p>The overall prevalence of <it>Schistosoma mansoni </it>infection was 27.8% (103/370) with stool egg load ranging from 24–6048 per gram of stool. 84.3%( 312) had light infections (<100 eggs/gm of stool), 10.8%( 40) had moderate infections (100–400 eggs/gm of stool) and 4.9% (18) had heavy infections (>400 egg/gm of stool). Prevalence was highest in the age group 12–14 years (49.5%) and geometric mean intensity was highest in the age group 9–11 years (238 epg). The prevalence and geometric mean intensity of infection among girls was lower (26%; 290 epg) compared to that of boys (29.6%; 463 epg) (t = 4.383, p < 0.05). Though 61%(225) of the pupils interviewed were aware of the existence of the disease, 78% (290)didn't know the mode of transmission and only 8% (30) of those found infected were aware of their infection status. In a multivariate logistic regression model, altitude and water source (crater lakes) were significantly associated with infection.</p> <p>Conclusion and recommendations</p> <p>The altitudinal threshold for <it>S. mansoni </it>transmission in Uganda has changed and use of crater water at an altitude higher than 1,400 m above sea level poses a risk of acquiring <it>S. mansoni </it>infection in western Uganda. However, further research is required to establish whether the observed altitudinal threshold change is as a result of climate change or other factors. It is also necessary to establish the impact this could have on the epidemiology of schistosomiasis and other vector-borne diseases in Uganda. In addition, sensitisation and mass treatment of the affected community is urgently required.</p

Religion's Role in Promoting Health and Reducing Risk Among American Youth

Although past research has long documented religion's salutary impact on adult health-related behaviors and outcomes, relatively little research has examined the relationship between religion and adolescent health. This study uses large, nationally representative samples of high school seniors to examine the relationship between religion and behavioral predictors of adolescent morbidity and mortality. Relative to their peers, religious youth are less likely to engage in behaviors that compromise their health (e.g., carrying weapons, getting into fights, drinking and driving) and are more likely to behave in ways that enhance their health (e.g., proper nutrition, exercise, and rest). Multivariate analyses suggest that these relationships persist even after controlling for demographic factors, and trend analyses reveal that they have existed over time. Particularly important is the finding that religious seniors have been relatively unaffected by past and recent increases in marijuana use.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66995/2/10.1177_109019819802500604.pd