Drive-noise tolerant optical switching inspired by composite pulses.

Electro-optic modulators within Mach-Zehnder interferometers are a common construction for optical switches in integrated photonics. A challenge faced when operating at high switching speeds is that noise from the electronic drive signals will effect switching performance. Inspired by the Mach-Zehnder lattice switching devices of Van Campenhout et al. [Opt. Express17(26), 23793 (2009).] and techniques from the field of Nuclear Magnetic Resonance known as composite pulses, we present switches which offer protection against drive-noise in both the on and off state of the switch for both the phase and intensity information encoded in the switched optical mode.

Laparoscopic versus open surgery for complicated appendicitis: a randomized controlled trial to prove safety.

BACKGROUND: To date, no randomized control trial has been performed comparing open appendectomy (OA) to laparoscopic appendectomy (LA) in complicated appendicitis. A systematic review and meta-analysis in 2010 concluded LA is advantageous to OA with less surgical site sepsis in complicated appendicitis; however, the level of evidence is weak (level 3a). The aim of the study was to determine whether LA is safe in the treatment of complicated appendicitis. Primary outcome included all-cause mortality and procedure-related mortality; secondary outcomes included intra-operative duration, rates of wound sepsis and re-intervention, length of hospital stay and re-admission rates. METHODS: One hundred and fourteen patients were randomized prospectively to either OA or LA using a computer-generated blind method. Patients who were either less than 12 years of age, had previous abdominal surgery or were pregnant were excluded. A team of senior surgeons capable of doing both OA and LA performed all procedures. RESULTS: The intra-operative duration, the rate of wound sepsis, the number of re-operations, the length of hospital stay and the rate of re-admissions between the OA and LA groups did not differ statistically. CONCLUSION: Laparoscopic appendectomy is safe in complicated appendicitis. Current Control Trials (ISRCTN92257749).

Loneliness and low life satisfaction associated with older adults' poor oral health.

Objective: To examine the association of older adults' loneliness, life satisfaction, and other psychological stressors and resources with oral health status. Methods: This study merged 2018 data from the Health and Retirement Study (HRS) CORE survey with the HRS-Dental Module, and Psychosocial and Lifestyle Questionnaire-Panel A "Leave Behind" surveys (HRS-LB)(N = 418). Dental Module outcomes of interest were self-rated oral health status (SROH), and oral health-related quality of life (OHQOL). Older adults reported on loneliness, life satisfaction, perceived age, social status, control, mastery, and chronic stressors. Three distinct profiles based on the distribution of loneliness and life satisfaction were previously identified in the combined HRS and HRS-LB study population (N = 4,703) using latent class analysis (LCA). Class A:"Not Lonely/Satisfied" adults had the fewest psychosocial risk factors and most resources; Class C:"Lonely/Unsatisfied" adults exhibited the opposite profile (most risk factors, fewest resources); Class B:"Lonely/Satisfied" adults exhibited loneliness with favorable life satisfaction. Regression models examined associations between LCA classes and fair/poor SROH and the OHQOL scale score and individual items, after adjusting for socio-demographics. Results: About 13% of older adults experienced loneliness, and about 16% reported low life satisfaction. About one-quarter (28%) of older adults reported fair/poor SROH, and they experienced more psychosocial risk factors than their counterparts with better oral health status. Nearly half the older adults were categorized in Class A:"Not Lonely/Satisfied" (n = 201), and about one-quarter each in Class B:"Lonely/Satisfied" (n = 103) and Class C:"Lonely/Unsatisfied" (n = 112). In fully adjusted models, Class B older adults had 1.81 (1.11-2.96) times greater odds of fair/poor SROH, and Class C had 4.64 (2.78-7.73) times greater odds of fair/poor SROH than Class A. Fully adjusted linear regression model results indicated a gradient by LCA class. OHQOL varied; Class A older adults had the best (lowest) OHQOL score (mean = 8.22, 4.37-12.10), Class B scored in the middle (mean = 12.00, 7.61-16.50), while Class C had the worst (highest) OHQOL score (mean = 16.20, 11.80-20.60). Conclusion: Loneliness, as a defining characteristic distinguishing three latent classes of older adults, was associated with more risk factors and poorer oral health outcomes. Loneliness, life satisfaction, perceived age, social status, control, mastery, and chronic stressors vary widely for older adults and matter for oral health and OHQOL.

Edentulism Predicts Cognitive Decline in the US Health and Retirement Cohort Study.

This longitudinal cohort study examines if 1) cognitive decline varies by birth cohort, adjusting for covariates, and 2) edentulism and nonuse of dental care predict 10-y cognitive decline (2008-2018). The Health and Retirement Study (HRS) features a representative sample of US adults over age 50. Eligibility criteria included having cognitive interview data available and responding to the question, "Have you lost all of your upper and lower natural permanent teeth?" at 2+ time points between 2006 and 2018. Use of dental care in the past 2 y was assessed. Linear mixed models for repeated measures estimated the trajectories of mean cognition over time for the birth cohorts, adjusted for baseline cognition, dentition status, dental care use, and covariates (demographic characteristics, health behaviors, and medical conditions). Cohort-by-time interaction terms were included to assess if cognitive decline varied by birth cohort. Ten-year change in cognition status (measured by HRS Cogtot27)-categorized as dementia (<7); cognitive impairment, not demented (7-11) 7≤Cogtot27<12; and normal (≥12)-was also investigated according to birth cohort, dentition status, and dental care use. Mean (SD) baseline age was 63.4 (10.1) y (n = 22,728). Older birth cohorts had greater cognitive decline than younger cohorts. Linear mixed-model estimates and 95% confidence intervals for protective factors for cognitive decline included higher baseline cognition (HRS Cogtot27) (0.49; 0.48-0.50), use of dental care in the past 2 y (0.17; 0.10-0.23), and covariates such as greater household wealth and being married. Risk increased with being edentulous (-0.42; -0.56 to -0.28), history of stroke or diabetes, less education, Medicaid recipient, current smoker, loneliness, and poor/fair self-rated health. Edentulism and irregular dental care are among important predictors of cognitive decline. Tooth retention and regular dental care throughout life appear to be important for maintaining oral and cognitive health.

Prediction Model Development and Validation of 12-Year Incident Edentulism of Older Adults in the United States.

INTRODUCTION: Edentulism affects health and quality of life. OBJECTIVES: Identify factors that predict older adults becoming edentulous over 12 y in the US Health and Retirement Study (HRS) by developing and validating a prediction model. METHODS: The HRS includes data on a representative sample of US adults aged >50 y. Selection criteria included participants in 2006 and 2018 who answered, "Have you lost all of your upper and lower natural permanent teeth?" Persons who answered "no" in 2006 and "yes" in 2018 experienced incident edentulism. Excluding 2006 edentulous, the data set (n = 4,288) was split into selection (70%, n = 3,002) and test data (30%, n = 1,286), and Monte Carlo cross-validation was applied to 500 random partitions of the selection data into training (n = 1,716) and validation (n = 1,286) data sets. Fitted logistic models from the training data sets were applied to the validation data sets to obtain area under the curve (AUC) for 32 candidate models. Six variables were included in all models (age, race/ethnicity, gender, education, smoking, last dental visit) while all combinations of 5 variables (income, alcohol use, self-rated health, loneliness, cognitive status) were considered for inclusion. The best parsimonious model based on highest mean AUC was fitted to the selection data set to obtain a final prediction equation. It was applied to the test data to estimate AUC and 95% confidence interval using 1,000 bootstrap samples. RESULTS: From 2006 to 2018, 9.7% of older adults became edentulous. The 2006 mean (SD) age was 66.7 (8.7) for newly edentulous and 66.3 (8.4) for dentate (P = 0.31). The baseline 6-variable model mean AUC was 0.740. The 7-variable model with cognition had AUC = 0.749 and test data AUC = 0.748 (95% confidence interval, 0.715-0.781), modestly improving prediction. Negligible improvement was gained from adding more variables. CONCLUSION: Cognition information improved the 12-y prediction of becoming edentulous beyond the modifiable risk factors of smoking and dental care use, as well as nonmodifiable demographic factors. KNOWLEDGE TRANSFER STATEMENT: This prediction modeling and validation study identifies cognition as well as modifiable (dental care use, smoking) and nonmodifiable factors (race, ethnicity, gender, age, education) associated with incident complete tooth loss in the United States. This information is useful for the public, dental care providers, and health policy makers in improving approaches to preventive care, oral and general health, and quality of life for older adults.

Topical Fluoride Effectiveness in High Caries Risk Adults.

This retrospective analysis of longitudinal data was developed to determine which types, combinations, and intensities of topical fluorides more effectively prevent new caries-related restorations and extractions in high caries risk adults. We included data from October 1, 2008, through June 30, 2018, from electronic dental and medical records and pharmacy database from the US Department of Veterans Affairs. Veterans who were eligible for continuing and comprehensive care, met the criteria of high caries risk (received 2 or more caries-related restorations within a 365-d period), and had 3 y of follow-up were included. Multivariable logistic regression models estimated the odds of caries-related treatment during the 1-y observation period, controlling for age, gender, race and ethnicity, illness burden (Selim comorbidity index), use of prescription medications, attendance at dental prophylaxis appointments, number of caries-related restorations during the index year, and time between first and last caries-related restoration during the index year. The study sample included 68,757 veterans, who were primarily male (91.5%), were White (73.6%), had a mean age of 59.2 ± 13.5 y, and had significant medical comorbidity as measured by the Selim index (3.7 ± 2.4 physical and 1.3 ± 1.2 mental diagnoses). They had 10.8 ± 6.3 prescription VA drug classes, took 0.6 ± 0.8 strong anticholinergic medications, and had 3.9 ± 2.6 teeth restored due to caries during the index year. Adjusted multivariable logistic regression models showed veterans who received a varnish or gel/rinse fluoride intervention versus no fluoride had an approximately 29% decreased odds of receiving caries-related treatment during the observation period (gel/rinse adjusted odds ratio [AOR] = 0.72; 95% confidence interval [CI], 0.67-0.76; varnish AOR = 0.71; 95% CI, 0.67-0.75). The receipt of a varnish and gel/rinse did not demonstrate statistically better odds than each intervention alone (AOR = 0.69; 95% CI, 0.64-0.75). A dose-response effect was observed. Two-plus applications of varnish versus none (AOR = 0.73; 95% CI, 0.69-0.77) and 2-plus applications of gel/rinse versus none (AOR = 0.71; 95% CI, 0.67-0.75) were more effective than 1 application of either modality versus none.

The disposition and metabolism of zibotentan (ZD4054): an oral-specific endothelin A receptor antagonist in mice, rats and dogs.

Zibotentan (ZD4054) is an oral-specific endothelin A receptor antagonist in development for the treatment of castration-resistant prostate cancer. In a number of preclinical studies, the disposition and metabolism of zibotentan were investigated in mice, rats and dogs. Following oral and intravenous administration, zibotentan was slowly absorbed (maximal concentration at approximately 4 h) and rapidly excreted, with the majority being eliminated by 48 h. The main route of elimination was via the urine in dogs and female rats, but via the faeces in male rats and mice of both sexes. Zibotentan was moderately bound to plasma proteins of all species examined (55-95%), and widely distributed throughout all tissues with the highest concentrations seen in the organs of excretion. Zibotentan was moderately metabolised. Zibotentan was well absorbed, moderately bound to plasma proteins, widely distributed and excreted predominantly via the urine.

Abnormal lymphatic phenotype in a CRISPR mouse model of the human lymphedema-causing Connexin47 R260C point mutation.

Connexin proteins form gap junctions controlling exchange of ions and small molecules between cells and play an important role in movement of lymph within lymphatic vessels. Connexin47 (CX47) is highly expressed in lymphatic endothelial cells and CX47 missense mutations, i.e., R260C, cosegregate with primary lymphedema in humans. However, studies utilizing CX47 knockout mice have failed to demonstrate any lymphatic anomalies. To unravel the lymphatic consequences of expressing a mutant CX47 protein, we used CRISPR technology to create a mouse carrying a Cx47 missense mutation (Cx47R259C) equivalent to the human CX47R260C missense mutation associated with human primary lymphedema. Intradermal Evans Blue dye injection identified a 2-fold increase in regional lymph nodes in homozygous Cx47R259C mice compared to wildtype, particularly in the jugular region (4.8 ± 0.4 and 2.0 ± 0.0, respectively, p<0.01). Associated lymphatic channels were increased in Cx47R259C mice and mesenteric lymph reflux occurred in homozygous Cx47R259C mice but not in wildtype. Contractility of superficial cervical lymphatics, assessed by pressure myography, was reduced in homozygous Cx47R259C mice compared to wildtype. In conclusion, our data are the first to demonstrate a role for the Cx47 protein in lymphatic anatomy and function. This phenotype is similar to that found with other valve deficient mouse mutants, e.g., in Foxc2. Of significance, this study is the first to use CRISPR technology to develop a pre-clinical model of primary lymphedema and demonstrates the importance of distinguishing between lack of and presence of mutant protein when developing clinically relevant animal models for translation of pre-clinical findings.

Antibiotic manipulation of intestinal microbiota to identify microbes associated with Campylobacter jejuni exclusion in poultry.

The ability of various subsets of poultry intestinal microbiota to protect turkeys from colonization by Campylobacter jejuni was investigated. Community subsets were generated in vivo by inoculation of day-old poults with the cecal contents of a Campylobacter-free adult turkey, followed by treatment with one antimicrobial, either virginiamycin, enrofloxacin, neomycin, or vancomycin. The C. jejuni loads of the enrofloxacin-, neomycin-, and vancomycin-derived communities were decreased by 1 log, 2 logs, and 4 logs, respectively. Examination of the constituents of the derived communities via the array-based method oligonucleotide fingerprinting of rRNA genes detected a subtype of Megamonas hypermegale specific to the C. jejuni-suppressive treatments.

The impact of immigration on tuberculosis rates in the United Kingdom compared with other European countries.

OBJECTIVE: To investigate whether trends in tuberculosis (TB) rates across Europe are linked to patterns of migration. DESIGN: Descriptive analysis of Organisation for Economic Co-operation and Development population statistics and EuroTB data for 21 European countries for 1996-2005. RESULTS: TB notification rates increased in only three of the 21 countries: the United Kingdom, Norway and Sweden. In all three countries, approximately three quarters of cases were foreign-born. The UK had the third highest number of foreign nationals overall, but the highest number from a country with a TB incidence > or =250 cases/100000 (219000, 13%). European countries with declining TB rates had varying patterns of migration, but did not generally receive migrants from very high-incidence countries and/or had a smaller proportion of their total TB cases in their migrant population. CONCLUSIONS: The increase in the rate of TB in the UK, which contrasts with most other European countries, may, at least in part, be due to the fact that a high proportion of UK cases occur in the foreign-born, coupled with a comparatively large number of foreign nationals from countries with a very high incidence of TB.

Salivary lysozyme and prevalent hypertension.

Although the etiology of essential hypertension is not clearly understood, endothelial dysfunction from chronic infection and/or impaired glucose metabolism may be involved. We hypothesized that salivary lysozyme, a marker for oral infection and hyperglycemia, might display a significant relationship with hypertension, an early stage of cardiovascular disease. Logistic regression analyses of the Kuopio Oral Health and Heart Study demonstrated that persons with higher lysozyme levels were more likely to have hypertension, after adjustment for age, gender, smoking, BMI, diabetes, the ratio of total cholesterol to HDL cholesterol, and C-reactive protein. The exposure to increasing quartiles of lysozyme was associated with adjusted Odds Ratios for the outcome, hypertension, 1.00 (referent), 1.25, 1.42, and 2.56 (linear trend p < 0.003). When we restricted the sample to the individuals without heart disease (N = 250), we observed a non-significant trend for increasing odds. Our hypothesis--"high salivary lysozyme levels are associated with the odds of hypertension"--was confirmed.

Evaluation of the use of UPLC-TOFMS with simultaneous [14C]-radioflow detection for drug metabolite profiling: application to propranolol metabolites in rat urine.

The non-selective beta-adrenergic receptor antagonist propranolol [1-(isopropylamino)-3-(1-naphthoxy)-2-propanol] is metabolised extensively in vivo. Enumerating and identifying the many metabolites that result from multiple biotransformations provides a considerable analytical challenge, greatly aided by efficient chromatography coupled to sensitive mass spectrometric detection. Here the use of the newly introduced high-resolution technique of "ultra performance liquid chromatography" (UPLC) linked to quadrupole time-of-flight mass spectrometry (TOFMS) with simultaneous [(14)C]-radioflow detection was applied to rapid metabolite profiling. [14C]-propranolol, dosed intraperitoneally to rat at 25 mg kg(-1) and 200 microCi kg(-1) was used as a model compound for this evaluation. Some 14 metabolites were detected in the urine by this technique including a number of conjugated metabolites such as sulphates, several isobaric glucuronides and two novel di-glucuronides.

New developments to support decision-making in contaminated inhabited areas following incidents involving a release of radioactivity to the environment.

The Chernobyl accident demonstrated that releases from nuclear installations can lead to significant contamination of large inhabited areas. A new generic European decision support handbook has been produced on the basis of lessons learned on the management of contaminated inhabited areas. The handbook comprises detailed descriptions of 59 countermeasures in a standardised datasheet format, which facilitates a comparison of features. It also contains guidance in the form of decision flowcharts, tables, check lists and text to support identification of optimised solutions for managing the recovery of inhabited areas within a framework consistent with ICRP recommendations. A new comprehensive inhabited-area dose model is also being developed for implementation in the ARGOS and RODOS decision support systems. Shortcomings of previous models are demonstrated. Decision support modelling in relation to malicious dispersion of radioactive matter in inhabited areas is also discussed. Here, the implications of, e.g., particle sizes and dispersion altitude are highlighted.

Sphingolipid-binding proteins.

Emerging information on sphingolipid metabolism and signaling is leading to a better understanding of cellular processes such as apoptosis, cancer, cell survival and aging. In this review, we discuss the involvement of sphingolipids in these processes and focus on underlying mechanisms based on sphingolipid:protein interactions. Due to the inherent difficulty of studying lipids, we discuss techniques that are useful in the elucidation of these interactions. We classify sphingolipid-binding proteins into four main classes: receptor, effector, enzyme, and transporter. Known structures of sphingolipid-binding proteins are surveyed, and sphingolipid-binding characteristics are described, acknowledging the limitations that there are presently insufficient protein:sphingolipid complexes for more definitive conclusions on this topic. Finally we summarize relevant literature to better inform the reader about sphingolipid:protein interactions.

In vitro modulation of cisplatin accumulation in human ovarian carcinoma cells by pharmacologic alteration of microtubules.

We have previously shown that forskolin and 3-isobutyl-1-methylxanthine (IBMX) increased accumulation of cisplatin (DDP) in DDP-sensitive 2008 human ovarian carcinoma cells in proportion to their ability to increase cAMP. Since the major function of cAMP is to activate protein kinase A, it was conjectured that the stimulation of DDP accumulation was mediated by a protein kinase A substrate. We now show that exposure of 2008 cells to forskolin resulted in phosphorylation of a prominent 52-kD membrane protein. Microsequencing of the band demonstrated it to be human beta-tubulin. Similarly, pretreatment of 2008 cells with the microtubule stabilizing drug taxol increased platinum accumulation in a dose-dependent manner. In 11-fold DDP-resistant 2008/C13*5.25 cells, decreased DDP accumulation was associated with enhanced spontaneous formation of microtubule bundles and decreased expression of beta-tubulin and the tubulin-associated p53 antioncogene relative to 2008 cells. 2008/C13*5.25 cells had altered sensitivity to tubulin-binding drugs, being hypersensitive to taxol and cross-resistant to colchicine. We conclude that pharmacologic alterations of tubulin enhance accumulation of DDP, and that the DDP-resistant phenotype in 2008/C13*5.25 cells is associated with tubulin abnormalities.

A distant gene deletion affects beta-globin gene function in an atypical gamma delta beta-thalassemia.

We describe an English family with an atypical gamma delta beta-thalassemia syndrome. Heterozygosity results in a beta-thalassemia phenotype with normal hemoglobin A2. However, unlike previously described cases, no history of neonatal hemolytic anemia requiring blood transfusion was obtained. Gene mapping showed a deletion that extended from the third exon of the G gamma-globin gene upstream for approximately 100 kilobases (kb). The A gamma-globin, psi beta-, delta-, and beta-globin genes in cis remained intact. The malfunction of the beta-globin gene on a chromosome in which the deletion is located 25 kb away suggests that chromatin structure and conformation are important for globin gene expression.

Tuberculosis in non-UK-born persons, England and Wales, 2001-2003.

SETTING: England and Wales, 2001-2003. OBJECTIVES: To describe demographic and clinical characteristics of tuberculosis (TB) in non-UK-born persons and compare with UK-born cases to inform public health action and health service provision. DESIGN: Analysis of surveillance data. RESULTS: Among the 67% of cases who were non-UK-born, TB incidence was 88/100000 compared to 4/100000 among the UK-born. UK-born minority ethnic groups were also at increased risk of TB. Although the highest TB incidence occurred in recent entrants to the UK, nearly half the cases had been resident for >or=5 years. The majority of non-UK-born cases originated from South Asia (48%) and sub-Saharan Africa (35%). The demographic characteristics of non-UK-born and UK-born cases differed. In addition, non-UK-born cases were less likely to have pulmonary TB than the UK-born (52% vs. 73%, chi(2) P<0.001), but were more likely to have isoniazid-resistant disease (8% vs. 6%, chi(2) P=0.002), depending on region of birth. CONCLUSIONS: During 2001-2003, most TB cases were non-UK-born. TB services need to take the characteristics of TB in this group into account. Furthermore, awareness of the risk of disease is required among the non-UK-born for many years after arrival into the UK, and among UK-born minority ethnic groups.

Musculoskeletal morbidity: the growing burden of shoulder pain and disability and poor quality of life in diabetic outpatients.

OBJECTIVE: To investigate shoulder pain and disability and quality of life (QoL) over 12 months in patients with diabetes and in a non-diabetic control group. METHODS: Cross-sectional study with 12-month follow-up in diabetic (n=189) and medical (n=99) outpatients employing the Shoulder Pain and Disability Index (SPADI) and SF-36 version 2. The results were analysed using restricted maximum likelihood (REML). RESULTS: The prevalence of current shoulder symptoms was 35% in diabetics and 17% in controls. Shoulder pain and disability as calculated by the SPADI were independently associated with diabetes (vs controls) and current shoulder symptoms, and worsened over 12 months. Disability scores worsened with age in diabetics, and pain scores were higher in diabetics than controls among patients reporting current shoulder symptoms. Poor physical QoL worsened over time in patients with diabetes and was worse in patients with current shoulder symptoms, whether they had diabetes or not. Mental QoL was worse only in patients with current shoulder symptoms. CONCLUSION: Shoulder symptoms are common, affecting 1 in every 3 diabetic patients and 1 in every 6 control patients. In this study shoulder pain, disability and physical QoL were poorer among diabetics and patients reporting current shoulder symptoms, and worsened over time. Mental QoL was worse in patients reporting current shoulder symptoms and was independent of diabetes. Therefore, shoulder symptoms are common, are associated with poor physical and mental QoL in addition to shoulder pain and disability, and are worse in patients with diabetes, even in a population with relatively moderate shoulder pain and disability.

Mechanisms of action for an anti-radiation vaccine in reducing the biological impact of high dose and dose-rate, low-linear energy transfer radiation exposure.

The development of an anti-radiation vaccine could be very useful in reducing acute radiation syndromes. Existing principles for the treatment of acute radiation syndromes are based on the amelioration of progressive pathophysiological changes, using the concept of replacement therapy. Active immunization by small quantities of the essential radiation-induced systemic toxins of what we call the Specific Radiation Determinant (SRD) before irradiation increased duration of life among animals that were irradiated by lethal or sub-lethal doses of gamma-radiation. The SRD toxins possess antigenic properties that are specific to different forms of acute radiation sickness. Intramuscular injection of larger quantities of the SRD toxins induce signs and symptoms in irradiated naive animals similar to those observed in acute radiation syndromes, including death. Providing passive immunization, at variable periods of time following radiation, with preparations of immune-globulins directed at the SRD molecules, can confer some protection in the development of clinical sequelae in irradiated animals. Improved survival rates and times were observed in animals that received lower, sublethal doses of the same SRDs prior to irradiation. Therefore, active immunization can be induced by SRD molecules as a prophylaxis. The protective effects of the immunization begin to manifest 15-35 days after an injection of a biologically active SDR preparation. The SRD molecules are a group of radiation toxins with antigenic properties that correlate specifically with different forms of radiation disease. The SRD molecules are composed of glycoproteins and lipoproteins that accumulate in the lymphatic system of mammals in the first hours after irradiation, and preliminary analysis suggests that they may originate from cellular membrane components. The molecular weight of the SRD group ranges from 200-250 kDa. The SRD molecules were isolated from the lymphatic systems of laboratory animals that were irradiated with doses known to induce the development of cerebral (SRD-1), non-specific toxic effects (SRD-2), gastrointestinal (SRD-3) and hematological (bone marrow) (SRD-4) syndromes. Our results suggest that an anti-radiation vaccine can be developed for prophylactic use against radiation damage induced by acute exposure to significant doses of low Linear Energy Transfer (LET) radiation for humans, including nuclear power workers, commercial and military pilots, cosmonauts/astronauts, nuclear-powered engine vessel operators and possibly even the civilian population in the case of a nuclear terrorism event.

The EXPURT model for calculating external gamma doses from deposited material in inhabited areas.

EXPURT, NRPB's model for calculating external gamma doses in inhabited areas, was originally developed in the mid-1980s. Deposition on surfaces in the area, the subsequent transfer of material between different surfaces or its removal from the system, and dose rates in various locations from material on the different surfaces are modelled. The model has been updated to take account of more recent experimental data on the transfer rates between surfaces and to make it more flexible for use in assessing dose rates following an accidental release. EXPURT is a compartmental model and models the transfer of material between the surfaces using a set of first order differential equations. It enables the impact of the decontamination of surfaces on doses and dose rates to be explored. The paper describes the EXPURT model and presents some preliminary results obtained using it.