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Locating clandestine graves is often a significant challenge for law enforcement and other investigators. A number of search techniques can be employed including visual assessments, canines, geophysical techniques, and imaging, often depending on the location/terrain, case information, and available resources. Dowsing is believed by some to be a reliable method for locating underground items of interest including water, oil, ore, and even graves; others, however, consider the practice to be controversial or even pseudoscience. Here we assess the ability of dowsing rods (wielded by previously inexperienced dowsers) to locate buried bones using a controlled blind test. Assemblages of bones were buried in three of nine holes. A control group of participants was asked to identify which holes they believed to contain bones by visual inspection, and a test group was asked to identify which holes they believed to contain bones using dowsing rods. Results indicate that neither method had a significant relationship with the true location of the bones (Matthew’s Correlation Coefficient –0.19 for the control group and 0.00 for the test group), and that there was no significant difference between the two groups (p = 0.36). In this study, dowsing was not found to be a reliable method of detecting buried bones. Some practitioners continue to advocate dowsing or other scientifically questionable search methods, even charging investigators or families substantial fees for these services. It is therefore important that such techniques are well-understood and rigorously tested, and that investigators seek and employ methods that are appropriate and valid.

Endocrine-disrupting contaminants (EDC's) are well known to alter sexual differentiation among vertebrates via estrogenic effects during development, particularly in organisms characterized by temperature-dependent sex determination. However, substances producing androgenic effects typically lack potency when tested in laboratory settings and are virtually unstudied in field settings. Here, we assay levels of a synthetic androgen, 17a-methyltestosterone (MT), in a heavily male-biased population of American crocodiles in the Tempisque River Basin of Costa Rica based on the recent hypothesis that this chemical is an EDC in developing crocodilian embryos. The presence of MT was documented in all fieldcollected samples of egg yolk and in plasma of all age classes in among population of crocodiles. Hatchlings exhibited higher plasma MT concentrations (102.1 ± 82.8 ng/mL) than juveniles (33.8 ± 51.5) and adults (25.9 ± 20.8 ng/mL). Among populations, crocodiles captured in the Tempisque River (62.9 ± 73.7 ng/mL) were higher in MT concentration than those from Tarcoles (13.3 ± 11.4 ng/mL) and negative controls (0.001 ± 0.0002 ng/mL). A mechanism for the bio-transport of MT and its subsequent effects is proposed. Universidad de Costa Rica/[741-B5-270]/UCR/Costa Rica Organization for Tropical Studies/[OTS 507]/OTS/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiología

A male-biased sex ratio of 3:1 has been reported for a population of American crocodiles (Crocodylus acutus) in the Tempisque River Basin, Guanacaste, Costa Rica. If confirmed, this would constitute one of the largest male-biased sex ratios reported for any population of a member of the genus Crocodylus. Here, we examine the aforementioned population of C. acutus and report on sex ratios of hatchling, juvenile, and adult age classes within a sample of 474 crocodiles captured in the Tempisque Basin between May 2012 and June 2014. Hatchling sex ratio is exceptionally male biased (3.5:1), an imbalance that is maintained in juveniles but is reduced in adults (1.5:1). Mark–recapture data document that juvenile males disperse from the study site, potentially to avoid competition, a process that reduces male bias in the adult age class. An increased role of males in human–crocodile conflict may be a result of juvenile males dispersing to human-inhabited areas.

Numerous anthropogenic factors represent environmental threats to Gulf Coast wetland ecosystems and associated fauna. American alligators (Alligator mississippiensis) have been subject to long-term management and used as ecological and physiological indicators of habitat quality in response to anthropogenic events and stochastic natural disasters. The present study monitored heterophil to lymphocyte ratios (an indicator of stress), in American alligators in a Louisiana intermediate marsh from 2009 to 2011, a time period that coincides with an oil inundation event that occurred in 2011. Sixteen alligators were observed and processed morphometrically (total length, snout-vent length and body mass). Heterophil to lymphocyte ratios were negatively correlated with size, suggesting larger American alligators were physiologically more resilient to the disturbance, more able to actively avoid these poor conditions, or are less affected by localized disturbance.

This study uses the American Alligator (Alligator mississippiensis) to assess the use of reproductive allometry as a tool to infer crocodilian population marginality based on conformation to advantageous life-history strategies. It is hypothesized that reproductive allometry, a morphometric relationship between mother's size and her reproductive output, varies intraspecifically between populations and that this variation reflects population marginality based on size, stress, temporal exploitation, habitat fragmentation, and/or the presence of social hierarchy. This hypothesis is tested using relative comparisons of allometric correlation between a marginal population inundated with saline storm surge from Hurricane Ike in southeastern Texas and a hypothesized unstressed core population in southeastern Louisiana. Heterophil to lymphocyte ratios fail to falsify the hypothesis of a saline stressor. The number of significant morphometric correlations between various parameters, degree of correlation (R2), and...

The harvest and incubation of American Alligator (Alligator mississippiensis) eggs is an important component to the commercial alligator harvest industry in the southeastern United States. As a result, various methodologies have been used to monitor alligator populations including abundance counts, stress quantification, and nesting surveys. Past studies have dismissed the importance of egg shape in crocodilians, Squamates, and turtles and deemed egg shape in birds and other amniotes as similar, in relation to functionality. The complexity of crocodilian eggs has been examined, and both turtle and Squamate eggs have been regarded recently as physiologically more intricate than bird eggs. This study introduces a physiological approach to monitor alligator populations in freshwater and low salinity environments by quantifying egg shape in correlation with varying salinity. We introduce a fractional semilandmark-shape template method to quantify egg shape within a geometric morphometric framework. This approach is beneficial because it allows for the quantification of shape for curved structures, such as eggs, which lack homologous landmarks. The results from this study suggest that alligator egg shape is correlated with varying salinity levels, such that variation in alligator egg shape at low salinities changes in gradient-like fashion, whereas salinities high enough to be deemed stressful result in reversion back to a low salinity egg shape or desiccation. This study elucidates a correlation that can be implemented in management and breeding techniques and opens the door to in-depth physiological examination of the system. The American Alligator (Alligator mississippiensis), like most crocodilian species, has become an economically valuable species with an extensive commercial market. As a result, the number of commercial ranches has increased over the last couple of decades, and many of these ranches are sustained by the harvest of alligator eggs from wild populations. The management of alligator populations has been professionally discussed publicly for more than 60 yr, as indicated by Giles and Childs (1949), Allen and Neill (1949), Taylor and Neal (1984), and Rice et al. (1999). Currently, numerous management protocols are in place to protect and sustain wild populations in the United States. Such protocols were founded on numerous academic endeavors (many listed in Joanen and McNease, 1980), and populations are consistently modeled and their

Effects of xenobiotics can be organizational, permanently affecting anatomy during embryonic development, and/or activational, influencing transitory actions during adulthood. The organizational influence of endocrine-disrupting contaminants (EDC’s) produces a wide variety of reproductive abnormalities among vertebrates that exhibit temperature-dependent sex determination (TSD). Typically, such influences result in subsequent activational malfunction, some of which are beneficial in aquaculture. For example, 17-amethyltestosterone (MT), a synthetic androgen, is utilized in tilapia farming to bias sex ratio towards males because they are more profitable. A heavily male-biased hatchling sex ratio is reported from a crocodile population near one such tilapia operation in Guanacaste, Costa Rica. In this study we test the effects of MT on sexual differentiation in American alligators, which we used as a surrogate for all crocodilians. Experimentally, alligators were exposed to MT in ovo at standard ecotoxicological concentrations. Sexual differentiation was determined by examination of primary and secondary sex organs post hatching. We find that MT is capable of producing male embryos at temperatures known to produce females and demonstrate a dose-dependent gradient of masculinization. Embryonic exposure to MT results in hermaphroditic primary sex organs, delayed renal development and masculinization of the clitero-penis (CTP). UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)

Spatial variation in global climate change makes population-specific responses to this enigmatic threat pertinent on a regional scale. Organisms with temperature-dependent sex determination (TSD) potentially possess a unique physiological susceptibility that threatens population viability if rapid environmental effects on sex ratios render populations non-viable. A heavily male-biased sex ratio for hatchling American crocodiles of the Tempisque Basin, Costa Rica requires assessment of how nest temperature affects sex determination at this site, how females might compensate for these effects when creating nests, and how current patterns of climate change might alter future sex ratios and survival in hatchling cohorts. We demonstrate high within-nest variation in temperature but predict a female bias at hatching based on nest temperatures quantified here. Further, our data suggest that egg size and metabolic heating associated with this factor outweighs microhabitat parameters and depth in influencing nest thermal regimes. Finally, we document regional warming in the Tempisque Basin over the last 15 years and project that further heating over the next 15 years will not yield hatchling sex ratios as male biased as those currently found at this site. Thus, we find no support for nest temperature or climate change as likely explanations for male-biased American crocodile (Crocodylus acutus) sex ratios in the Tempisque Basin. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiología

Exposures of occupants in school buses to on-road vehicle emissions, including emissions from the bus itself, can be substantially greater than those in outdoor settings. A dual tracer method was developed and applied to two school buses in Seattle in 2005 to quantify in-cabin fine particulate matter (PM2.5) concentrations attributable to the buses' diesel engine tailpipe (DPMtp) and crankcase vent (PMck) emissions. The new method avoids the problem of differentiating bus emissions from chemically identical emissions of other vehicles by using a fuel-based organometallic iridium tracer for engine exhaust and by adding deuterated hexatriacontane to engine oil. Source testing results showed consistent PM:tracer ratios for the primary tracer for each type of emissions. Comparisons of the PM:tracer ratios indicated that there was a small amount of unburned lubricating oil emitted from the tailpipe; however, virtually no diesel fuel combustion products were found in the crankcase emissions. For the li...

Intensive poultry production generates over 100,000 t of litter annually in West Virginia and 9 x 10(6) t nationwide. Current available technological alternatives based on thermophilic anaerobic digestion for residuals treatment are diverse. A modification of the typical continuous stirred tank reactor is a promising process being relatively stable and owing to its capability to manage considerable amounts of residuals at low operational cost. A 40-m3 pilot plant digester was used for performance evaluation considering energy input and methane production. Results suggest some changes to the pilot plant configuration are necessary to reduce power consumption although maximizing biodigester performance.

Particulate matter from diesel exhaust (DPM) is a pollutant of increasing concern, but its concentrations are difficult to measure in the environment. There are no unique chemical characteristics for DPM, so elemental carbon (EC) and black carbon (BC) measurements have historically been used to estimate its concentrations. However, both methods have limitations, and neither is capable of identifying specific sources. That results in significant uncertainties in the inferred DPM concentrations. In this study an intentional fuel-based tracer, iridium, was used to mark the DPM from a school bus's exhaust. Emissions tests established the mass ratio of DPM-iridium in the exhaust. Iridium measurements inside the bus during normal operations could then be used to calculate DPM concentrations without the limitations of methods relying on nonspecific markers. Previous studies have attributed in-bus concentrations of more than 30 μ/m3 to the bus's exhaust, but they relied on nonspecific methods with a sensitivity of approximately 0.1 μ/m3. In this study the average measured DPMSB concentration was 0.22 μ/m3—about 1% of previous estimates. Measurement sensitivity was approximately 0.001 μ/m3—100 times better than that of other methods. The sensitivity and specificity achieved show that this tracer method can resolve major ambiguities and uncertainties in estimates of actual DPM concentrations. The ability to estimate accurately the contributions of different sources to DPM concentrations provides a needed tool to evaluate proposed emission reduction strategies reliably.

The article discusses the composition of the granite stone from the island of Ailsa Craig, Scotland used in the sport of curling, with information on curling in the Winter Olympic Games, the design of the curling stone, and the geological history of Ailsa Craig.

We monitored two Seattle school buses to quantify the buses' self pollution using the dual tracers (DT), lead vehicle (LV), and chemical mass balance (CMB) methods. Each bus drove along a residential route simulating stops, with windows closed or open. Particulate matter (PM) and its constituents were monitored in the bus and from a LV. We collected source samples from the tailpipe and crankcase emissions using an on-board dilution tunnel. Concentrations of PM(1), ultrafine particle counts, elemental and organic carbon (EC/OC) were higher on the bus than the LV. The DT method estimated that the tailpipe and the crankcase emissions contributed 1.1 and 6.8 mug/m(3) of PM(2.5) inside the bus, respectively, with significantly higher crankcase self pollution (SP) when windows were closed. Approximately two-thirds of in-cabin PM(2.5) originated from background sources. Using the LV approach, SP estimates from the EC and the active personal DataRAM (pDR) measurements correlated well with the DT estimates for tailpipe and crankcase emissions, respectively, although both measurements need further calibration for accurate quantification. CMB results overestimated SP from the DT method but confirmed crankcase emissions as the major SP source. We confirmed buses' SP using three independent methods and quantified crankcase emissions as the dominant contributor.

The effect of heating strategy on power consumption and performance of a pilot plant anaerobic digester treating chicken litter, under thermophilic conditions, has been studied. Heating strategy was evaluated using three different spans (0.2 degrees C, 0.6 degrees C, and 1.0 degree C) for triggering the temperature control system from target temperature (56.7 degrees C). The hydraulic retention time in the pilot plant digester was in the range of 32 to 37 days, varying the total solids concentration fed from 5% to 6%. The results showed that under the experimental conditions, heating was the most energy-demanding process with 95.5% of the energy used. Increments up to 7.5% and 3.8%, respectively, on mechanical and heating power consumption, were observed as the span, for triggering the temperature control system from target temperature, was increased. Under the experimental conditions studied here, an increment of 30.6% on the global biodigester performance index was observed when a span of 1.0 degree C was compared to the one of 0.2 degrees C.

The article discusses the results of a study that found batters increased their changes of being struck by a retribution pitch during a baseball game when the weather was hot.

The article discusses a project, called the Billion Prices Project, which is software developed by economists at the Massachusetts Institute of Technology (MIT) that measures inflation faster and cheaper than conventional methods.