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Hawksbill sea turtle Eretmochelys imbricata nesting on Long Island, Antigua, West Indies (also known as Jumby Bay) has been monitored since 1987. Although the numbers of nesting females remained relatively constant for the first 11 survey seasons (1987–1997), inclusion of more recent data (1998–2004) in the analysis reveals a statistically significant upward trend. In particular, neophytes have shown a significant upturn in numbers, whereas the remigrant subpopulation has remained stationary. This indicates that recruitment is driving the upward trend in the total number of nesters. Predictive models based on the Poisson distribution suggest that the neophyte subpopulation will continue to grow in size by an average of 10% per annum. Model-based predictions and their limitations are discussed. The Jumby Bay Hawksbill Project, which has monitored and protected nesting hawksbills and their eggs since the project's onset, is one among several factors that may contribute to the recent increase in nesting females.

The temperature dependences of the d.c. magnetic susceptibility and Verdet constant in two zirconium based fluoride glasses have been studied. One sample has as a minor constituent dysprosium which has a large magnetic moment that dominates the material's magnetic character. The second sample, containing a small amount of europium, shows both Van Vleck paramagnetism and a Curie-Weiss behaviour. The Curie-Weiss character is believed to come from small amounts of and/or produced during the sample's manufacturing process. An upper limit is placed on the amount of magnetic zirconium in the material.

Context: Changes in serum vitamin D metabolites and calcium absorption with varying doses of oral vitamin D3 in healthy children are unknown. Objective: Our objective was to examine the dose-response effects of supplemental vitamin D3 on serum vitamin D metabolites and calcium absorption in children living at two U.S. latitudes. Design: Black and white children (n = 323) participated in a multisite (U.S. latitudes 34° N and 40° N), triple-masked trial. Children were randomized to receive oral vitamin D3 (0, 400, 1000, 2000, and 4000 IU/d) and were sampled over 12 weeks in winter. Serum 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) were measured using RIA and intact PTH (iPTH) by immunoradiometric assay. Fractional calcium absorption was determined from an oral stable isotope 44Ca (5 mg) in a 150-mg calcium meal. Nonlinear and linear regression models were fit for vitamin D metabolites, iPTH, and calcium absorption. Results: The mean baseline 25(OH)D value for the entire sample was 70.0 nmol/L. Increases in 25(OH)D depended on dose with 12-week changes ranging from −10 nmol/L for placebo to 76 nmol/L for 4000 IU. Larger 25(OH)D gains were observed for whites vs blacks at the highest dose (P < .01). Gains for 1,25(OH)2D were not significant (P = .07), and decreases in iPTH were not dose-dependent. There was no dose effect of vitamin D on fractional calcium absorption when adjusted for pill compliance, race, sex, or baseline 25(OH)D. Conclusion: Large increases in serum 25(OH)D with vitamin D3 supplementation did not increase calcium absorption in healthy children living at 2 different latitudes. Supplementation with 400 IU/d was sufficient to maintain wintertime 25(OH)D concentrations in healthy black, but not white, children.

The Ecological Monitoring and Compliance (EMAC) Program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, monitors the ecosystem of the Nevada National Security Site and ensures compliance with laws and regulations pertaining to NNSS biota. This report summarizes the program's activities conducted by National Security Technologies, LLC, during calendar year 2011. Program activities included (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem monitoring, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) monitoring of the Nonproliferation Test and Evaluation Complex. During 2011, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.

The Ecological Monitoring and Compliance (EMAC) Program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), monitors the ecosystem of the Nevada National Security Site (NNSS) and ensures compliance with laws and regulations pertaining to NNSS biota. This report summarizes the program’s activities conducted by National Security Technologies, LLC (NSTec), during calendar year 2010. Program activities included (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem monitoring, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) monitoring of the Nonproliferation Test and Evaluation Complex (NPTEC). During 2010, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.

From 1 July 1987 to 31 December 1988, a total of 317 animals (91% of which were dogs) were confirmed to have rabies in Hermosillo, Mexico. The median age of rabid dogs was 1 year, 69% were male, and 98% were owned. The epizootic started in the southern areas of the city, rapidly involved the entire city, and persisted mainly in lower socioeconomic status areas. The area of the city and mean household size were significant predictor variables for the population density of rabid dogs around household clusters (Poisson linear regression, P0.001 and P = 0.03, resp). Approximately 2.5% of city residents were bitten by dogs in 1987, with the rate of reported dog bite injuries being positively correlated with mean household size and the proportion of households that owned dogs. Visits to the city health centre for evaluation of possible exposures to rabies increased by 135% after the start of the epizootic; approximately 273 per 100,000 city residents were administered a full or partial course of rabies post-exposure prophylaxis in 1987. Children were at greatest risk for exposures to rabies, accounting for 60% of all reported animal bite injuries evaluated at the health centre. Also they were more likely than older persons to have received bite injuries to the head, face, and neck (odds ratio = 21.6, 95% confidence interval = 5.4, 186.5).Almost all cases of human rabies result from bites by rabid dogs. Controlling dog rabies is therefore crucial for humans. 317 animals, 91% of which were dogs, were confirmed to have rabies in Hermosillo, Mexico, from July 1, 1987, to December 31, 1988. The dogs were of median age 1 year, 69% were male, and 98% were owned. The epizootic started in the southern areas of the city, spread quickly through the city, and persisted largely in lower socioeconomic status areas. Approximately 2.5% of city residents were bitten by dogs in 1987, with the rate of reported dog bite injuries positively correlated with mean household size and the proportion of households which owned dogs. Visits to the city health center for evaluation of possible exposures to rabies increased by 135% after the start of the epizootic over which approximately 273 per 100,000 city residents were administered a full or partial course of rabies post-exposure prophylaxis in 1987. Comprising 60% of all reported animal bite injuries evaluated at the center, children were at greatest risk for exposures to rabies. Children were also more likely than older people to have received bite injuries to the head, face, and neck.

Context: The extent to which 25-hydroxyvitamin D [25(OH)D] and IGF-I influence bone mineral content (BMC) accrual from early to mid-puberty is unclear. Objective, Setting, and Participants: This study sought to determine relationships among 25(OH)D, IGF-I, and BMC in community-dwelling prepubertal females (n = 76; aged 4–8 yr at baseline) over a period of up to 9 yr. Design: The hypothesis that changes in IGF-I vs. 25(OH)D are more strongly associated with BMC accrual was formulated after data collection. 25(OH)D and IGF-I were log-transformed and further adjusted using two-way ANOVA for differences in season and race. Linear mixed modeling (including a random subject-specific intercept and a random subject-specific slope on age) was employed to analyze the proportion of variance the transformed 25(OH)D and IGF-I variables explained for the bone outcomes. Results: IGF-I was more strongly associated with BMC accrual than 25(OH)D at the total body (R2 = 0.874 vs. 0.809), proximal femur (R2 = 0.847 vs. 0.771), radius (R2 = 0.812 vs. 0.759), and lumbar spine (R2 = 0.759 vs. 0.698). The rate of BMC accrual was positively associated with changes in IGF-I but negatively associated with 25(OH)D. When IGF-I and 25(OH)D were included in the same regression equation, 25(OH)D did not have a significant predictive effect on BMC accrual above and beyond that of IGF-I. Conclusions: These prospective data in early adolescent females indicate that both 25(OH)D and IGF-I have a significant impact on bone mineral accrual; however, the positive association of IGF-I and BMC accrual is greater than the negative association of 25(OH)D and BMC accrual.

Human parvovirus B19, the cause of erythema infectiosum, has recently been associated with adverse fetal outcomes. During a large outbreak of erythema infectiosum in Connecticut, a survey was conducted on 571 (90%) of 634 school and day-care personnel to determine the risk of acquiring B19 infection. Serologic evidence of B19 infection was determined by using an enzyme-linked immunosorbent assay. Of the school and day-care personnel, 58% had evidence of previous B19 infection. The minimal rate of B19 infection in susceptible personnel during the outbreak was 19%. The risk was increased for teachers and day-care providers who had contact with younger children and with greater numbers of ill children. These results suggest that B19 infection is an occupational risk for school and day-care personnel.

A well‐established method for the accurate measurement of small changes in ac magnetic susceptibility is to initially null and then monitor the output of the susceptometer as various parameters are modified. Use of a computer‐controlled phase shift filter has allowed us to build a system that will introduce virtually orthogonal signals to compensate for the in‐phase and out‐of‐phase components of the output. The system described is designed for use over the frequency range 50 Hz–4 kHz. Extended frequency ranges are possible with only slight modifications.

It is shown that a relatively small non-linear behavior of the velocity drive system used in Mossbauer effect studies yields pseudo-discontinuities in the isomer shift near the critical temperatureT c of a magnetic-paramagnetic transition. The anomaly of the57Fe isomer shift in iron is attributed to this effect.

A furnace system is presented for Mossbauer‐effect spectroscopy at temperatures up to 1200 K with a temperature stability better than 0.03 K. This system allows the study of samples at high temperatures in an external magnetic field of a few kG with a homogeneity of better than 1%. Our measurements show that a few degrees above the Curie temperature TC, such an external field induces a considerable hyperfine field at 57Fe nuclei in iron. In addition, the magnetic hyperfine field and the isomer shift of 57Fe in metallic iron are measured over a temperature range of 300 to 1100 K. It is shown that a relatively small nonlinear behavior of the Mossbauer velocity drive system may result in a pseudodiscontinuity in the isomer shift δ near the Curie temperature, explaining the anomalous behavior observed for δ of iron and of some iron alloys in this region.

The recoilless fractionf of57Fe in iron is determined as a function of temperatureT in the vicinity of the Curie temperatureTc using a source of57Co diffused in a foil of 100% enriched56Fe. Our results show thatf does not undergo an abrupt change atTc, but that in the ferromagnetic phase |df/dT| is larger than in the non-ferromagnetic phase. This indicates that the ferromagnetic interaction increases the bond between the iron atoms, and thus contributes to the stability of the iron lattice belowTc.

Theoretical as well as experimental investigations were carried out for the propagation of leaky waves along an important class of optical thin‐film waveguides. For this type of guiding structure which may consist of heteroepitaxial deposition of ZnS or ZnSe on GaAs, the dielectric constant of the thin film is less than that of the substrate. Consequently, only the leaky type of guided waves may exist. Theoretical results show that the attenuation constants of leaky modes, which may be TE or TM, are inversely proportional to (thickness of layer)3 and directly proportional to (wavelength)2, and that TM modes are more lossy than TE modes. The existence of these leaky modes has also been demonstrated for three different thicknesses.

Triangular bending elements that can be applied to irregular plate or shell networks are presented. Equilibrium as well as elastic properties of these elements are derived. Also presented are parallelogram plate bending elements whose elastic properties include core shear deformations for sandwich or thick plates. The elements presented are peculiar to the matrix force method with virtual work concepts forming the basis for computation of the elastic properties of the elements. A method of providing transition elements between triangular and parallelogram networks is also given.

Myopia is common in Western populations but is considered rare in nonindustrialized population groups. However, studies in undeveloped areas of the Arctic and sub-Arctic have demonstrated increased rates of myopia among young Inuit adults indigenous to the region. We examined the refractive status of Yupik Eskimos, a group that had not previously been evaluated. Our subjects were young adults born between November 1960 and December 1962 to persons living in 10 villages in southwestern Alaska. The refractive status was obtained for 92% of these persons. The prevalence of myopia (refractive error -0.50 D or greater) was 68%, a rate among the highest reported for a general population anywhere in the world. The young women were significantly more myopic than the young men (mean refractive errors -1.91 and -1.36 D respectively). Astigmatism and myopia were positively correlated (r = 0.20, p less than 0.01). The etiology of myopia in this population is under study.

In 1981, a hepatitis B virus vaccine demonstration project was conducted in 1630 Yupik Eskimos in southwest Alaska. Levels of antibody to hepatitis B surface antigen and markers for hepatitis B virus infection in vaccinees were monitored yearly for 5 years. After 5 years of follow-up, 19% of those who initially had an immune response to vaccine of 10 sample ratio units or greater subsequently had levels of antibody to hepatitis B surface antigen lower than 10 sample ratio units. During the 5 years after the first dose of vaccine, in three responders and one person with an antibody to hepatitis B surface antigen response lower than 10 sample ratio units, antibody to hepatitis B core antigen developed, and the level of antibody to hepatitis B surface antigen was boosted. Hepatitis B surface antigen did not develop in any subjects, and none had clinical hepatitis. In the 5 years following the demonstration project, the annual incidence of hepatitis B virus infection decreased from 50 cases per 1000 population before the vaccine trial to 0.45 per 1000.

A 1960-62 study of southwestern Alaskan Eskimos documented an infant mortality rate--102.6 deaths per 1,000 live births--that was four times greater than that of U.S. whites. In 1980-81, 20 years after the original study, a similar cohort was identified in this population so that changes in infant mortality and other birth characteristics could be examined. Average birth weight and the amount of prenatal care received by the mothers increased from 1960 to 1980. Birth weight and prenatal visits were positively correlated. Results of the followup also revealed a 1980-81 infant mortality rate--17.1 deaths per 1,000 live births--that was less than a fifth of the 1960-62 rate and no longer significantly different from the national rate. Major changes associated with the decrease in mortality during the first 28 days of life (neonatal mortality) were a significant increase in the proportion of infants born in hospitals and an associated decrease in the number of deaths of infants weighing less than 2,500 grams at birth. The reduction in mortality during the rest of the first year of life was related to a decrease in deaths due to infectious diseases, particularly measles and pertussis. Changes in infant mortality reflect the increased availability of health care in this region, improved immunization programs, and the establishment of the Bethel Prematernal Home in Bethel, AK.

Four port single mode fiber optic directional couplers have been fabricated exhibiting coupler losses approaching 0.1% (.005 dB). A new experimental technique with an integrating sphere was used to measure these low losses. The couplers, which can be tuned for any coupling ratio, have coupled as much as 99.8% of the total input power in one fiber to another fiber. In this high coupling, low loss regime new polarization dependent effects were observed in the couplers.

In 1981, a hepatitis B vaccine demonstration project was initiated among Yupik Eskimos of southwest Alaska to demonstrate that, under field conditions, the vaccine was safe, immunogenic, and efficacious. Laboratory tests for serologic markers of hepatitis B virus infection (HBsAg, anti-HBs, and anti-HBc) performed on sera collected in May 1981 from 3,988 residents of 17 remote Eskimo villages revealed that 2,645 (66.3%) had no evidence of hepatitis B virus infection. Because of a limited supply of vaccine, specific criteria for selection were used so that those at highest risk of infection would be immunized first. In November 1981, the first dose of vaccine was administered to 1,693 carefully selected individuals. The second dose was administered to 1,678 (99.1%) of those who received the first dose, and the final dose was administered to 1,630 persons (96.3%). Serologic follow-up showed the vaccine to be safe (0.4% experienced minor adverse reactions) and immunogenic (97.4% developed antibody). Vaccine-induced antibody levels were significantly higher for persons less than 30 years of age (p less than 0.001) and for females (p less than 0.001). Vaccine recipients were also protected from hepatitis B virus infection (p = 0.002). This public health measure proved to be feasible and effective in this remote arctic population despite difficult conditions for delivery and administration of this temperature-sensitive vaccine. This strategy for immunization is now being applied on a larger scale in Alaska as part of a program for the primary prevention of this infection and its sequelae.

Structural analysis modification by force method accounting for elastic property changes of some elements