Assessing the Benefits and Costs of Homeland Security Research: A Risk-Informed Methodology with Applications for the U.S. Coast Guard.

This article describes a methodology for risk-informed benefit-cost analyses of homeland security research products. The methodology is field-tested with 10 research products developed for the U.S. Coast Guard. Risk-informed benefit-cost analysis is a tool for risk management that integrates elements of risk analysis, decision analysis, and benefit-cost analysis. The cost analysis methodology includes a full-cost accounting of research projects, starting with initial fundamental research costs and extending to the costs of implementation of the research products and, where applicable, training, maintenance, and upgrade costs. The benefits analysis methodology is driven by changes in costs and risks leading to five alternative models: cost savings at the same level of security, increased security at the same cost, signal detection improvements, risk reduction by deterrence, and value of information. The U.S. Coast Guard staff selected 10 research projects to test and generalize the methodology. Examples include tools to improve the detection of explosives, reduce the costs of harbor patrols, and provide better predictions of hurricane wind speeds and floods. Benefits models and estimates varied by research project and many input parameters of the benefit estimates were highly uncertain, so risk analysis for sensitivity testing and simulation was important. Aggregating across the 10 research products, we found an overall median net present value of about $385 million, with a range from $54 million (5th percentile) to $877 million (95th percentile). Lessons learned are provided for future applications.

Development of challenge models to evaluate the efficacy of a vaccine to reduce carriage of Salmonella in peripheral lymph nodes of cattle.

Because challenge models to infect peripheral lymph nodes (PLNs) with Salmonella have not been reported, we performed a series of experiments to develop and refine challenge models to evaluate an intervention applied at the animal level and to provide initial estimates of efficacy of an intervention (i.e., a vaccine) to aid in the design of future studies. In each of four experiments, steers (control or vaccinated) were inoculated with Salmonella strains Montevideo or Newport, and in experiment IV, Salmonella Senftenberg was also used. Calves were euthanized 14 to 42 days postinoculation, and PLNs were collected. In the first experiment, calves were challenged with ∼10¹° Salmonella cells, and few treatment differences were observed 14 days postchallenge. However, by day 21, Salmonella Newport was recovered from fewer vaccinated calves than control calves (P < 0.05). In experiment II, calves were challenged with ∼107 Salmonella cells and, after two necropsies (14 and 28 days postchallenge), only one lymph node was Salmonella positive; therefore, the study was terminated. In experiment III, calves were again challenged with ∼10¹° Salmonella cells, and no significant effect of vaccine was observed in calves challenged with Montevideo or Newport strains. A transdermal route of challenge was explored in experiment IV, using a 10-lancet, allergy testing instrument. Sixteen steers were challenged with either Salmonella Newport or Salmonella Montevideo (Salmonella Newport right legs; Salmonella Montevideo left legs), and all steers were challenged on the lower abdomen with Salmonella Senftenberg. Transdermal inoculation resulted in predictably Salmonella-positive PLNs, and a modest vaccine effect was detected. Because it is well tolerated by the calves and results in predictable and regionally specific Salmonella recovery from PLNs, the transdermal route of challenge may be preferred by researchers wishing to evaluate the impact of interventions designed to reduce the carriage of Salmonella in PLNs.

Evaluation of the potential antimicrobial resistance transfer from a multi-drug resistant Escherichia coli to Salmonella in dairy calves.

Previous research conducted in our laboratory found a significant prevalence of multi-drug resistant (MDR) Salmonella and MDR Escherichia coli (MDR EC) in dairy calves and suggests that the MDR EC population may be an important reservoir for resistance elements that could potentially transfer to Salmonella. Therefore, the objective of the current research was to determine if resistance transfers from MDR EC to susceptible strains of inoculated Salmonella. The experiment utilized Holstein calves (approximately 3 weeks old) naturally colonized with MDR EC and fecal culture negative for Salmonella. Fecal samples were collected for culture of Salmonella and MDR EC throughout the experiment following experimental inoculation with the susceptible Salmonella strains. Results initially suggested that resistance did transfer from the MDR E. coli to the inoculated strains of Salmonella, with these stains demonstrating resistance to multiple antibiotics following in vivo exposure to MDR EC. However, serogrouping and serotyping results from a portion of the Salmonella isolates recovered from the calves post-challenge, identified two new strains of Salmonella; therefore transfer of resistance was not demonstrated under these experimental conditions.

The effect of chlortetracycline on faecal microbial populations in growing swine.

The effect of antimicrobial use on the gastrointestinal microbiota of food animals is of increasing concern as bacteria accumulate resistance to multiple antimicrobials. Only a small fraction of the gastrointestinal microbiome is culturable, complicating characterisation of the swine gastrointestinal ecosystem. The objective of this study was to determine the effect of a growth promotion dose (50g/ton) of chlortetracycline on the phylogenetic diversity of bacteria from swine faeces using a culture-independent method. Four freshly weaned pigs were provided a grower ration of primarily corn (63.7%) and soybean meal (25.2%) for 21 days; on Day 21 for 4 weeks the diet of two pigs was medicated with 50g/ton chlortetracycline. Faecal material was collected from each pig on Days 0, 14, 23, 28, 35, 42 and 49 for 454-pyrosequencing of the 16S rRNA gene. UniFrac analysis of pyrosequencing data showed no significant difference in bacterial diversity based on diet and among pigs (P>0.05) fed the low-level dose of chlortetracycline. The most abundant phyla in both treatment groups were Firmicutes, Bacteroidetes, Proteobacteria and Spirochaetes. Higher concentrations of chlortetracycline (e.g. 200g/ton or 400g/ton) may be required to observe a shift in the gastrointestinal flora in swine faeces compared with the low-level dose in this study. Studies of broader scope are needed to understand thoroughly how growth-promoting antimicrobials influence the gut microflora and benefit food animal growth efficiency.

Development of colonic microflora as assessed by pyrosequencing in dairy calves fed waste milk.

The objective of the current study was to examine the effect of pasteurization of waste milk, used to feed dairy calves, on the bacterial diversity of their lower gut. Using 16S rDNA bacterial tag-encoded FLX amplicon pyrosequencing, fecal samples from dairy calves, ages 1 wk to 6 mo old and fed either pasteurized or nonpasteurized waste milk, were analyzed for bacterial diversity. Calves were maintained on 2 separate farms and, aside from how the waste milk was treated, were housed and cared for similarly. Fifteen calves were sampled from each age group (1, 2, and 4 wk, and 2, 4, and 6 mo of age; n=90 samples per milk treatment, 180 total samples) on each farm via rectal palpation and the samples shipped and frozen before analysis. In general, bacterial diversity, as represented by the total number of different species, was greater for the calves fed pasteurized waste milk at all ages (except 1 wk of age) and increased with increasing age in both treatments. Proteobacteria, Bacteroidetes, and Firmicutes were the predominant phyla. Differences in phyla and class were observed among treatments and age of calf but with no consistent trends. Salmonella were detected in 9 out of 14 (64%) of the 1-wk-old calves fed nonpasteurized milk. Treponema, an important beneficial bacterium in cattle rumen, was more prevalent in the pasteurized waste milk-fed animals and became higher in the older animals from this group. Escherichia-Shigella were detected among treatments at all ages, and highest at 1 wk of age, averaging approximately 21 and 20% of all bacteria for calves fed pasteurized and nonpasteurized waste milk, respectively, and decreasing as calves aged (2.6 and 1.3%). The consistent detection of Salmonella in the younger animals fed nonpasteurized milk and its absence in all other groups is an important finding related to this feeding practice.

Lack of effect of feeding citrus by-products in reducing salmonella in experimentally infected weanling pigs.

The objective of the current research was to determine if feeding the citrus by-products(D) -limonene (DL) and citrus molasses would reduce the concentration and prevalence of Salmonella in weanling pigs experimentally infected with Salmonella Typhimurium. Twenty crossbred weanling pigs (average body weight [BW], 19.9 kg) were randomly assigned to one of four treatments: control, low-dose DL (1.5 ml/kg of BW per day), high-dose DL (3.0 ml/kg of BW per day), and citrus molasses (0.05 kg/kg of BW per day). Treatments were administered in the feed (twice daily) for 7 days, with one-half of the dose administered at each feeding. Fecal samples were collected twice daily (prior to administration of treatment) and cultured for quantitative and qualitative determination of the challenge strain of Salmonella. Upon termination of the study, pigs were euthanized and tissues from the stomach, ileum, cecum, spiral colon, and rectum, as well as luminal contents, were collected. In addition, the popliteal and ileocecal lymph nodes and liver, spleen, and tonsil tissue were collected for qualitative Salmonella culture. No significant treatment differences (P > 0.05) were observed among treatments for fecal concentration or prevalence of Salmonella throughout the 7-day collection period. Likewise, no treatment differences (P > 0.05) were observed for any of the tissue or luminal content samples collected. Salmonella was not cultured from the muscle-bound popliteal lymph node but was cultured from the mesenteric ileocecal lymph nodes. While there were no effects in the current experiment, future research may examine the effect of a lower challenge dose and/or different administration (dose or duration) of the citrus by-products.

A missing error term in benefit-cost analysis.

Benefit-cost models are frequently used to inform environmental policy and management decisions. However, they typically omit a random or pure error which biases downward any estimated forecast variance. Ex-ante benefit-cost analyses create a particular problem because there are no historically observed values of the dependent variable, such as net present social value, on which to construct a historically based variance as is the usual statistical approach. To correct this omission, an estimator for the random error variance in this situation is developed based on analysis of variance measures and the coefficient of determination, R(2). A larger variance may affect decision-maker's choices if they are risk averse, consider confidence intervals, exceedance probabilities, or other measures related to the variance. When applied to a model of the net benefits of the Clean Air Act, although the probability of large net benefits increases, the probability that the net present value is negative also increases from 0.2 to 4.5%. A framework is also provided to assist in determining when a variance estimate would be better, in a utility sense, than using the current default of a zero error variance.

Evaluation of the effect of gallium maltolate on fecal Salmonella shedding in cattle.

Strategies aimed at reducing fecal shedding of Salmonella and other foodborne pathogens may be effective for limiting transmission of pathogens from food animals to humans. The objective of this study was to determine the effectiveness of gallium maltolate (GaM) against Salmonella in vitro and to determine whether oral administration of GaM would reduce fecal shedding of Salmonella in cattle. Gallium is a semimetal exhibiting antimicrobial properties against some pathogenic bacteria, including Salmonella, by exploiting their need for iron to survive and replicate. In vitro growth studies were performed in pure cultures of Salmonella and in mixed cultures from ruminal fluid. Inclusion of GaM in culture medium or in mixed cultures of ruminal fluid resulted in a significant reduction in growth of Salmonella, suggesting that GaM may be effective for limiting growth and survival in vivo. Therefore, we subsequently administered two doses of GaM to Holstein steers, experimentally infected them with Salmonella, and quantitatively and qualitatively monitored fecal shedding at 12-h intervals. Sixty hours after beginning treatment, cattle were euthanized, and luminal contents and tissue were aseptically harvested from the rumen, jejunum, spiral colon, cecum, and rectum. The luminal contents were processed for quantitative and qualitative analysis of the challenge strains of Salmonella, and tissue samples were enriched and plated for qualitative analysis. We found no significant differences between control and treated animals in quantitative levels of Salmonella in the feces or the luminal contents. Likewise, we observed no pattern between control and treated animals in the frequency of positive or negative results from enriched feces, luminal contents, or tissue samples. These results suggest that GaM was not effective for reducing Salmonella in cattle.

Prediction of beef carcass salable yield and trimmable fat using bioelectrical impedance analysis.

Bioelectrical impedance technology (BIA) is capable of providing an objective method of beef carcass yield estimation with the rapidity of yield grading. Electrical resistance (Rs), reactance (Xc), impedance (I), hot carcass weight (HCW), fat thickness between the 12th and 13th ribs (FT), estimated percentage kidney, pelvic, and heart fat (KPH%), longissimus muscle area (LMA), length between electrodes (LGE) as well as three derived carcass values that included electrical volume (EVOL), reactive density (XcD), and resistive density (RsD) were determined for the carcasses of 41 commercially fed cattle. Carcasses were subsequently fabricated into salable beef products reflective of industry standards. Equations were developed to predict percentage salable carcass yield (SY%) and percentage trimmable fat (FT%). Resulting equations accounted for 81% and 84% of variation in SY% and FT%, respectively. These results indicate that BIA technology is an accurate predictor of beef carcass composition.

Acyl-homoserine-lactone autoinducer in the gastrointestinal [corrected] tract of feedlot cattle and correlation to season, E. coli O157:H7 prevalence, and diet.

Acyl-homoserine-lactone autoinducer (AHL) produced by nonenterohemorrhagic Escherichia coli species in cattle appears to be required for enterohemorrhagic E. coli (EHEC) colonization of the gastrointestinal tract (GIT). The current research aimed to examine the effect of season, diet, EHEC shedding, and location within the GIT on AHL prevalence in the ruminant. Luminal content samples were collected from the rumen and rectum of feedlot cattle at slaughter in the spring, summer, fall, and winter for culture of E. coli O157:H7 and AHL determination. During the spring collection, samples were additionally collected from the cecum and small intestine, but these samples all were AHL negative and therefore not examined again. To assess the influence of diet on AHL prevalence, 14 lambs were fed either 100% forage or 80% concentrate diets and experimentally inoculated with EHEC. At 8 days after infection, all the lambs were killed, and necropsies were taken, with luminal contents collected from the GIT. The collections from the feedlot cattle had AHL in 100% of the rumen content samples from the spring, summer, and fall, but not in any of the winter samples. No other GIT samples from feedlot cattle were AHL positive, and all the samples from the sheep study were AHL negative. The cattle seemed to show a weak correlation between ruminal AHL and EHEC prevalence. This research found AHL only in the rumen and not in the lower GIT of feedlot cattle. However, it is unclear whether this is because the pH of the lower gut destroys the AHL or because a lack of certain bacteria in the lower gut producing AHL.

Irish coroners' attitudes towards suicide and its prevention.

BACKGROUND: Coroners routinely enquire into suicide deaths and communicate with people bereaved by suicide. However, no research has been conducted into coroners' attitudes towards suicide and its prevention. AIMS: We assessed attitudes towards suicide among Irish coroners in order to determine their understanding of suicide and its prevention. METHODS: An internationally validated questionnaire assessing attitudes towards suicide was sent to all coroners in the Republic of Ireland and Northern Ireland. RESULTS: Sixty completed questionnaires (response 62%) were analysed. Overall, the coroners' responses reflected openness towards communication about suicide and suicide prevention initiatives. Approximately, one in five favoured the attitudes that suicide is a right or that it may be a justifiable resolution. Only 23% agreed that people who die by suicide are usually mentally ill. CONCLUSIONS: Irish coroners favour communication about suicide and have a positive attitude towards its prevention but they appear to underestimate the prevalence of mental illness.

An exploratory observational study to develop an improved method for quantifying beef carcass salable meat yield.

Eighty-seven grain-finished steers were harvested, evaluated, and fabricated into wholesale cuts to determine what measured composition indicators most accurately describe the percentage of closely trimmed salable meat yield. Indicators of lean and fat composition present at the cross-section between the 12th and 13th ribs were objectively evaluated using Assess image analysis software. Salable meat yield ranged from 50.18% to 72.92%, trimmable fat yield ranged from 12.87% to 36.69%, and bone yield ranged from 10.07% to 19.21%. Regression models were developed to estimate percentage of total salable meat yield. Composition indicators chosen to predict salable meat yield included hot carcass weight (HCW), perinephric fat weight, longissimus muscle area (LMA), subcutaneous fat thickness (SFT), ratio of LMA to subcutaneous fat area, and ratio of subcutaneous fat depth to HCW. These results indicate that prediction of beef carcass salable meat yield can be improved via modification to current measures used in the USDA yield grade equation and addition of new measures.

Technical note: the United States Department of Agriculture beef yield grade equation requires modification to reflect the current longissimus muscle area to hot carcass weight relationship.

With the adoption of visual instrument grading, the calculated yield grade can be used for payment to cattle producers selling on grid pricing systems. The USDA beef carcass grading standards include a relationship between required LM area (LMA) and HCW that is an important component of the final yield grade. As noted on a USDA yield grade LMA grid, a 272-kg (600-lb) carcass requires a 71-cm(2) (11.0-in.(2)) LMA and a 454-kg (1,000-lb) carcass requires a 102-cm(2) (15.8-in.(2)) LMA. This is a linear relationship, where required LMA = 0.171(HCW) + 24.526. If a beef carcass has a larger LMA than required, the calculated yield grade is lowered, whereas a smaller LMA than required increases the calculated yield grade. The objective of this investigation was to evaluate the LMA to HCW relationship against data on 434,381 beef carcasses in the West Texas A&M University (WTAMU) Beef Carcass Research Center database. In contrast to the USDA relationship, our data indicate a quadratic relationship [WTAMU LMA = 33.585 + 0.17729(HCW) -0.0000863(HCW(2))] between LMA and HCW whereby, on average, a 272-kg carcass has a 75-cm(2) (11.6-in.(2)) LMA and a 454-kg carcass has a 96-cm(2) (14.9-in.(2)) LMA, indicating a different slope and different intercept than those in the USDA grading standards. These data indicate that the USDA calculated yield grade equation favors carcasses lighter than 363 kg (800 lb) for having above average muscling and penalizes carcasses heavier than 363 kg (800 lb) for having below average muscling. If carcass weights continue to increase, we are likely to observe greater proportions of yield grade 4 and 5 carcasses because of the measurement bias that currently exists in the USDA yield grade equation.

Collection of wind-borne haematophagous insects in the Torres Strait, Australia.

Circumstantial evidence has implicated wind-borne mosquitoes (Diptera: Culicidae) in the introduction of Japanese encephalitis (JE) virus into Australia from the New Guinea mainland. A study was initiated on Saibai Island in the northern Torres Strait, during January and February 2000, to identify the potential source of insects collected in aerial (kytoon) and surface-level traps. Wind speed and direction were recorded to determine wind profiles during insect sampling. Northerly winds capable of carrying insects from New Guinea to Saibai Island were only present on three out of 18 nights sampled. Only three male mosquitoes, comprising two Verrallina funerea (Theobald) and one Ochlerotatus vigilax (Skuse), were collected in aerial samples, and were most likely of local origin. Culicoides midges were also collected in aerial nets and included gravid/parous C. bundyensis Lee and Reye, and one parous C. histrio Johannsen. Highest densities of arthropods (up to 1562/million m3) were on 30 January 2000 when NW winds, sustained for six hours, probably introduced midges from the New Guinea mainland. Adult mosquitoes (including three female Ve. funerea and a single female Ficalbia) and Culicoides (including two gravid C. bundyensis and one parous C. cordiger Macfie) were also collected in 2 m high mast nets during northerly surface winds. Although the results do not provide evidence that wind-blown mosquitoes introduced JE from New Guinea into Australia, they do not preclude that strong N winds associated with low pressure systems SW of the Torres Strait could have done so. However, results suggest that Culicoides were more likely than mosquitoes to reach high altitude and travel long distances during the light N winds experienced during the study.

Clearance of barium from the oesophagus with diet cola and metoclopramide: a one stop approach to patients with dysphagia.

AIM: To establish a "one-stop" dysphagia service in which a consultation, barium swallow and endoscopy can all be performed in the same hospital visit. MATERIALS AND METHODS: In order to allow both barium swallow examination and endoscopy to be performed on the same day, a novel technique for clearing barium from the upper gastrointestinal tract was established. Following the barium swallow examination, patients were given diet cola and metoclopramide syrup. If appropriate, an upper gastrointestinal endoscopy was then performed shortly afterwards. The service was piloted for 6 months in which time 25 patients were investigated in this way. RESULTS: All patients were seen within 2 weeks of referral. The mean time between barium swallow and endoscopy was 3 h 38 min (range, 1 h 50 min to 5 h 20 min). In all 24 patients in whom an endoscopy was performed, barium had been satisfactorily cleared from the oesophagus and stomach. CONCLUSION: This technique allows both barium swallow and upper gastrointestinal endoscopy to be performed on the same day, providing a rapid, safe and accurate diagnosis with minimum patient inconvenience. Mitchell, J., (2001). Clinical Radiology56, 64-66

Comparison of Gas Temperatures Measured by Coherent Anti-Stokes Raman Spectroscopy (CARS) of O(2) and N(2).

We investigate the accuracy of temperature measurements by coherent anti-Stokes Raman spectroscopy (CARS) of O(2) and use measurements taken with N(2) CARS and a thermocouple for comparison. Scanning vibrational CARS spectra of O(2) and N(2) were recorded over a broad range of temperatures: between 294 K and 1900 K in air that was heated in a tube furnace and at approximately 2450 K in a fuel-lean CH(4)-O(2)-N(2) flame. Temperatures were derived from least-squares fits of simulated and experimental spectra. Both the fundamental vibrational band and the first hot vibrational band were included in fitting. In the case of the tube furnace, the N(2) and the O(2) CARS temperature measurements agreed to within 3%, and results were similar with the thermocouple; in the flame the agreement was to within 1%. We conclude that, for cases in which O(2) is present in sufficient concentrations ( approximately 10% or greater), the accuracy of O(2) thermometry is comparable with that of N(2).

Mosquito (Diptera: Culicidae) dispersal: implications for the epidemiology of Japanese and Murray Valley encephalitis viruses in Australia.

One hypothesis to explain the southern extension of Japanese encephalitis (JE) virus from Papua New Guinea into the Torres Strait islands in 1995 and to mainland Australia in 1998 is the dispersal of infected mosquitoes, particularly Culex annulirostris Skuse from which JE virus has been isolated repeatedly. To investigate whether this species disperses in this manner, mosquitoes were identified from 368 aerial kite trap collections operated at 50-310 m (altitude) at inland New South Wales between November 1979 to December 1984. Forty samples (9 during daylight and 31 at night) contained mosquitoes, of which 221 could be identified as Culex australicus Dobrotworsky & Drummond (58.8%), Culex annulirostris (21.3%), Anopheles annulipes Walker s.l. (10.4%), Aedes theobaldi (Taylor) (7.2%), Aedes rubrithorax (Macquart) (1.4%), and Aedes sagax (Skuse) (< 0.9%). During the night, mosquitoes were found in 22.6% of the collections at a mean density (+/- SD) of 91.3 +/- 151.7/10(6) m3 of air sampled. During the day, only 3.8% were positive at a mean density 125.3 +/- 152.1. When examined in relation to possible flying time and wind speed, mean +/- SD dispersal distances by day and night were 23.9 +/- 15.3 km and 152.4 +/- 116.3 km, respectively. These data provide circumstantial evidence that aerial carriage southward approximately 200 km from Papua New Guinea to Cape York peninsula is feasible, but that southern dispersal of Murray Valley encephalitis virus infected mosquitoes from tropical to temperate Australia is unlikely.

Core biopsy of the bowel wall: efficacy and safety in the clinical setting.

OBJECTIVE: The purpose of this study was to evaluate the efficacy and complications of percutaneous 18-gauge core biopsies of lesions of the bowel wall using CT and sonographic guidance. A retrospective study was made of 15 biopsy procedures performed on 12 patients with suspected neoplasia of the gastrointestinal tract. The biopsies were performed when there were no sites of metastatic disease more readily accessible to biopsy and the lesion was inaccessible to endoscopic techniques or when the endoscopic biopsy findings were negative. CONCLUSION: Three biopsy procedures provided inadequate samples and the biopsies were repeated, giving a total of 15 biopsy procedures. A tissue diagnosis was made in all 12 patients. All procedures were well tolerated, and no immediate or delayed complications occurred. Percutaneous core biopsy of bowel wall masses is a safe technique that allows a histologic diagnosis to be obtained in difficult cases when other methods cannot provide an adequate tissue sample.