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We present a novel approach to developing a unified radiocarbon-based chronology for multiple sediment cores from a location where radiocarbon dating is challenging. We used 36 radiocarbon ages from eight terminal Pleistocene and Holocene sediment cores with correlated stratigraphies. Stratigraphic correlation was accomplished using a combination of high-resolution photography, high-resolution X-ray fluorescence-based elemental composition data, and volcanic tephra identification. Results show that despite problems associated with potential contamination or radiocarbon reservoir effect, a useful age-depth model has been created for the correlated lacustrine sections of these eight sediment cores, providing chronological controls for future paleoenvironmental analyses of the cores.

Sentinel wetlands at Cuyahoga Valley National Park (NP) comprise a set of twenty important management areas and reference sites. These wetlands are monitored more closely than other wetlands in the wetlands monitoring program and are the focus of the volunteer monitoring program for water levels. We used the Ohio Rapid Assessment Method (ORAM) to evaluate habitat in the sentinel wetlands. A total of 37 long-term sample plots have been established within these wetlands to monitor biological condition over time using vegetation as an indicator. Vegetation is intensively surveyed using the Vegetation Index of Biotic Integrity (VIBI), where all plant species within the plot are identified to the lowest taxonomic level possible (genus or species). Sample plots were surveyed twice from 2008 to 2018 and the vegetation data were evaluated using five metrics: VIBI, Floristic Quality Assessment Index (FQAI), percent sensitive plant species, percent invasive graminoids, and species richness. These metrics are discussed for each location. This report also highlights relevant land use histories, common native plant species, and invasive species of concern at each wetland. This is the first report in a two-part series, designed to summarize the results from intensive vegetation surveys completed at sentinel wetlands in 2008–2018. Boston Mills, Virginia Kendall Lake, Stumpy Basin, Columbia, and Beaver Marsh are all in excellent condition at one or more plots. They have unique habitats with some specialized plant species. Fawn Pond is in good condition at most plots and scores very high in comparison to other wetlands within the riverine mainstem hydrogeomorphic class. Metric scores across mitigation wetlands were low. Two of the three wetlands (Brookside and Rockside) are not meeting the benchmarks originally established by the United States Army Corps of Engineers and Ohio Environmental Protection Agency. Krejci is still a young mitigation site and success will be determined over time. Park-supported invasive species control efforts will be crucial for long-term success of these sites and future mitigation/restoration projects. The wetlands monitored because of proposed ecological restoration projects (Pleasant Valley, Stanford, and Fawn Pond) have extensive invasive plant communities. These restoration sites should be re-evaluated for their feasibility and potential success and given an order of prioritization relative to the newer list of restoration sites. Cuyahoga Valley NP has added many new areas to their list of potential wetland restoration sites after these areas were selected, and there may be better opportunities available based on restoration objectives. Restoration goals should be based on the park's desired future conditions, and mitigation goals of outside partners may not always be in line with those. The multiple VIBI plots dispersed throughout the large wetlands at Cuyahoga Valley NP detected and illuminated spatial patterns in condition. Many individual wetlands had a wide range of VIBI scores within their boundaries, sometimes reflecting localized disturbances, past modifications, and management actions. Most often, these large fluctuations in condition were linked to local invasive plant infestations. These infestations appear to be the most obvious and widespread threat to wetland ecosystems within the park, but also the most controllable threat. Some sensitive species are still present in some of the lowest scoring plots, which indicates that invasive plant species control efforts may pay off immediately with a resurgence of native communities. Invasive plant control at rare habitat sites would have large payoffs over time by protecting some of the park's most unique wetlands. Reference wetlands would also be good demonstration sites for park managers to try to maintain exemplary conditions through active management. Through this work, park managers can evaluate the feasibility, effectiveness, and scalability of management practices required to maintain wetland condition.

Current archaeological research on cultigens emphasizes the protracted and intimate human interactions with wild species that defined paths to domestication and, with certain plants, profoundly impacted humanity. Tobacco arguably has had more impact on global patterns in history than any other psychoactive substance, but how deep its cultural ties extend has been widely debated. Excavations at the Wishbone site, directed at the hearth-side activities of the early inhabitants of North America’s desert west, have uncovered evidence for human tobacco use approximately 12,300 years ago, 9,000 years earlier than previously documented. Here we detail the preservation context of the site, discuss its cultural affiliation and suggest ways that the tobacco may have been used. The find has implications for our understanding of deep-time human use of intoxicants and its sociocultural intersection with food crop domestication. The finding of tobacco seeds in a Pleistocene-age fire hearth suggests people learned of this plant’s intoxicant value shortly after their arrival in the Americas, initiating a long heritage of use with global societal impact.

Mollusk and ostracode assemblages from the distal Old River Bed delta (ORBD) contribute to our understanding of the Lake Bonneville basin Pleistocene-Holocene transition (PHT) wetland and human presence on the ORBD (ca. 13,000–7500 cal yr BP). Located on U.S. Air Force-managed lands of the Great Salt Lake Desert (GSLD) in western Utah, USA, the area provided 30 samples from 12 localities. The biological assemblages and the potential water sources using 87Sr/86Sr analyses showed wetland expansion and contraction across the PHT, including the Younger-Dryas Chronozone (YDC). The record reflects cold, freshwater conditions, which is uncharacteristic of the Great Salt Lake Desert, after recession of Lake Bonneville. Lymnaea stagnalis jugularis, Cytherissa lacustris, and possibly Candona sp. cf. C. adunca, an endemic and extinct species only reported from Lake Bonneville, suggest cold-water environments. Between 13,000–12,400 cal yr BP, a shallow lake formed, referred to as the Old River Bed delta lake, fed by Lake Gunnison, as shown by 87Sr/86Sr ratios of 0.71024–0.71063 in mollusk fossils collected at the ORBD, characteristic of the Sevier basin. These findings add paleoenvironmental context to the long-term use of the ORBD by humans in constantly changing wetland habitats between 13,000–9500 cal yr BP.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover and frequency of these plant species is essential for developing risk-based approaches to managing them. Based on surveys conducted in 2006, 2013, 2018, and 2021, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 38 potentially problematic plant species in Pea Ridge National Military Park. Of the 35 species found in 2021, we characterized 13 as very low frequency, 9 as low frequency, 9 as medium frequency, and 4 as high frequency. Of these 35 species, midpoint cover estimates of 4 medium frequency and all 4 high frequency species exceeded the 10-acre threshold. The 10-acre threshold represents a limit beyond which eradication of a problematic plant species is likely not possible. Clearing of eastern redcedar (Juniperus virginiana) continues to be evident in our observations, and sericea lespedeza (Lespedeza cuneata) appears to have increased as clearing progressed. The rapid increase in Japanese stiltgrass (Microstegium vimineum) appears to be parkwide. Because of the number, extent, and cover of problematic plants in the park, control efforts should focus on early detection treatments and strategic treatment of high priority, widespread species to protect features of the park’s natural and cultural landscapes. High priority species may include plant species capable of rapid spread, species at low population levels, and species that can be effectively controlled.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover and frequency of these plant species is essential for developing risk-based approaches to managing them. Based on surveys conducted in 2006, 2013, 2016, and 2020, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 50 potentially problematic plant species in George Washington Carver National Monument. Of the 35 species found in 2020 , we characterized 8 as very low frequency, 9 as low frequency, 10 as medium frequency, and 8 as high frequency. Of these, midpoint cover estimates of only 1 high frequency species, tall fescue, exceeded the 10-acre threshold. Because of the number, extent, and cover of problematic plants in the park and the small park size, control efforts should focus on treating high priority species across the entire park. High priority species may include plant species capable of rapid spread, species at low population levels, and species that can be effectively controlled.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover and frequency of these plant species is essential for developing risk-based approaches to managing them. Based on surveys conducted in 2006, 2013, 2016, and 2020, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 53 potentially problematic plant species in Wilson’s Creek National Battlefield. Of the 40 species found in 2020, we characterized 9 as very low frequency, 13 as low frequency, 9 as medium frequency, and 9 as high frequency. Of these 40, midpoint cover estimates of 1 low-frequency, 4 medium-frequency, and 8 high-frequency species exceeded the 10-acre threshold. The 10-acre threshold represents a limit beyond which eradication of a problematic plant species is likely not possible. Because of the number, extent, and cover of problematic plants in the park and the small park size, control efforts should focus on treating high priority species across the entire park. High priority species may include plant species capable of rapid spread, species at low population levels, and species that can be effectively controlled.

Limited excavations at Nangara-Komba Shelter along the northern margin of the Congo Basin have recovered evidence for intermittent and at times intensive human visits beginning approximately 5100 c...

Problematic species, which include invasive, exotic, and harmful species, fragment native ecosystems, displace native plants and animals, and alter ecosystem function. In National Parks, such species negatively affect park resources and visitor enjoyment by altering landscapes and fire regimes, reducing native plant and animal habitat, and increasing trail maintenance needs. Recognizing these challenges, Heartland Inventory and Monitoring (I&M) Network parks identified problematic plants as the highest-ranking vital sign across the network. Given the need to provide early detection of potential problematic plants (ProPs) and the size of network parks, the Heartland I&M Network opted to allocate available sampling effort to maximize the area searched. With this approach and the available sampling effort in mind, we developed realistic objectives for the ProP monitoring protocol. The monitoring objectives are: 1. Create a watch list of ProPs known to occur in network parks and a watch list of potential ProPs that may invade network parks in the future, and occasionally update these two lists as new information is made available. 2. Provide early detection monitoring for all ProPs on the watch lists. 3. Search at least 0.75% and up to 40% of the reference frame for ProP occurrences in each park. 4. Estimate/calculate and report the abundance and frequency of ProPs in each park. 5. To the extent possible, identify temporal changes in the distribution and abundance of ProPs known to occur in network parks. ProP watch lists are developed using the best available and most relevant state, regional, and national exotic plant lists. The lists are generated using the PriorityDB database. We designed the park reference frames (i.e., the area to be monitored) to focus on accessible natural and restored areas. The field methods vary for small parks and large parks, defined as parks with reference frames less than and greater than 350 acres (142 ha), respectively. For small parks, surveyors make three equidistant passes through polygon search units that are approximately 2-acres (0.8 ha) in size. For large parks, surveyors record each ProP encountered along 200-m or 400-m line search units. The cover of each ProP taxa encountered in search units is estimated using the following cover scale: 0 = 0, 1 = 0.1-0.9 m2, 2 = 1-9.9 m2, 3 = 10-49.9 m2, 4 = 50-99.9 m2, 5 = 100-499.9 m2, 6 = 499.9-999.9 m2, and 7 = 1,000-4,999.9 m2. The field data are managed in the FieldDB database. Monitoring is scheduled to revisit most parks every four years. The network will report the results to park managers and superintendents after completing ProP monitoring.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover and frequency of these plants is essential for developing risk-based approaches to managing these species. Based on surveys conducted in 2008, 2011, 2015, and 2019, Heartland Network staff and contractors identified a cumulative total of 51 potentially problematic plant species in Hopewell Culture National Historical Park. Of the 37 species found in 2019, we characterized 7 as very low frequency, 9 as low frequency, 17 as medium frequency, and 4 as high frequency. Of these, midpoint cover estimates of 2 medium frequency and 2 high frequency species exceeded the 10-acre threshold. Because of the number, extent, and cover of problematic plants in the park and the small park size, control efforts should focus on treating high priority species across the entire park. High priority species may include plant species capable of rapid spread, species at low population levels, and species which can effectively be controlled.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover, distribution, and location of these plants is essential for developing risk-based approaches to managing these species. Based on surveys conducted in 2006, 2011, 2015, and 2019, Heartland Network staff and contractors identified a cumulative total of 45 potentially problematic plant taxa in Lincoln Boyhood National Memorial. Of the 34 species found in 2019, we characterized 4 as very low frequency, 14 as low frequency, 9 as medium frequency, and 7 as high frequency. A single species exceeded a 10-acre threshold based on a mid-point estimate. Because of the number of problematic plant taxa, as well as the extent and cover of problematic plants in the park and the small park size, control efforts should focus on treating high priority species across the entire park. High priority species may include plant species capable of rapid spread, species at low population levels, and species which can effectively be controlled.

Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover, distribution, and location of these plants is essential for developing risk-based approaches to managing these species. Based on surveys conducted in 2006, 2011, 2015, and 2019, Heartland Network staff and contractors identified a cumulative total of 28 potentially problematic plant taxa in Arkansas Post National Memorial. Of the 23 species found in 2019, we characterized 9 as very low frequency, 7 as low frequency, 5 as medium frequency, and 2 as high frequency. Cover of all species was low with a single species slightly exceeding a 1-acre threshold based on a midpoint estimate. Efforts to control the woody invasive black locust, Chinese privet, and hardy orange appear to have successfully reduced the cover of these plants across the Memorial Unit. Japanese stiltgrass may have been increasing as recently as 2015, but a combination of recent flooding and control efforts may have stemmed the spread of this invasive grass. Efforts to control localized patches of Chinaberry tree also appear to have reduced the cover of this species. Outside of the problematic species currently subject

Recently, Lupo et al. (2015, 2018) reported novel data on the nature and timing of late Holocene human settlement and iron production in the northern Congo Basin rain forest, southern Central Afric...

Archaeological surveys and excavations in the NGotto Forest Reserve, Central African Republic, discovered 98 artefact concentrations or cultural features that included ceramic scatters, iro...

A multi-year effort to develop streamlined, fit for purpose cannabis analyzers for potency analysis is described herein. These analyzers are easy to use and deliver the highest accuracy, reproducibility and reliability. Cannabis and hemp analyzers are useful in cannabis QC testing laboratories, as well as academic labs, agricultural labs, pharmaceutical labs and forensic labs. This chapter also details application of cannabis analyzers to flower (dry product), edibles, tinctures and oils. We examine the need for simplified analyzers for cannabis analyzers, as well as future development opportunities.

Physical therapy intervention is often sought to treat cervical spine conditions and a comprehensive physical therapy examination has been associated with more favourable outcomes. The cervical relocation test (CRT) is one method used to assess joint position sense (PS) integrity of the cervical spine. Previous research has found significant differences in the CRT between symptomatic and asymptomatic subjects. Impaired kinaesthetic awareness in the cervical spine may be associated with degenerative joint disease, chronicity of the complaint and increased susceptibility to re-injury.The purpose of this study was to determine the intertester and intratester reliability of cervical relocation using the cervical range of motion instrument (CROM) and an affixed laser (AL) device among subjects with and without a history of neck pain. In addition, it was hypothesised that those individuals with a history of neck pain would have greater difficulty on the CRT.A total of 50 asymptomatic subjects (n = 50) were assigned to two researchers. The CRT was performed for each tester by the subject rotating the cervical spine for three trials to the right and left for the CROM and AL.The results indicate a significant intertester reliability of the CROM (interclass correlation coefficient (ICC) = 0.717[0.502-0.839]; 0.773[0.595-0.873]) for the subjects in this sample.This study demonstrated that the CROM is a reliable device for measuring cervical relocation between different testers. Future research should investigate if the CRT is predictive of prognosis in patients with cervical pathology.

Cannabis light preparations are products derived or containing dried female inflorescences of Cannabis sativa belonging to Chemotype III (THC/CBD ratio1); the total THC (THC+THCA) content in the crop must not exceed 0.2 % in accordance with the EU regulation. In Italy the most recent law for industrial hemp (242/2016) states that only for farmers this limit is extended to 0.6 %. On the other hand, the Ministry of the Interior published a note stating that the sale or the presence in the markets of products (inflorescences, concentrates, essences and resins) or plants with concentrations higher than 0.5 % constitutes a crime. In this confusing legislation framework, it is very important to assess the legality of hemp, determining the total amount of THC. To this end a reliable LC-UV analytical method was developed and validated taking into account parameters such as precision, accuracy, linearity, repeatability of peak area and retention time, limit of detection (LOD= 0.002 % for all cannabinoids) and limit of quantification (LOQ= 0.005 % for all cannabinoids). Accuracy was expressed as the relative error (Er%), while precision was measured as the coefficient of variation (CV%). A CV% below 3 % and Er% between ± 6 % were obtained. The linearity was proven in the concentration range 0.005-1 % for THC, THCA and CBN and 0.005 %-50 % for CBD and CBDA. The analytical method was applied to more than nine hundred cannabis light samples. Based on the law 242/2016, only 18 % of the crops are to be considered legal for the market (total THC0.2 %). If the circular of the Ministry of the Interior should be converted as a proper law, a substantial amount of cannabis light preparations (24 %) would be considered illegal (total THC0.5 %). On the other hand, the most of the inflorescences (58 %) have a total THC content comprised between 0.2 % and 0.5 %, and it is not clear whether these products could be sold or not. Moreover, Cannabis light products are not authorized for human consumption, even if everybody knows that this is their primary use. In conclusion, the cannabis light panorama in Italy is quite confused and more specific and clear legislation should be proposed.

In the Great Basin, large-scale trapping features designed to capture multiple artiodactyls include fences or drive lines and corrals with associated wings. More than 100 of these features are known in the Great Basin. An experimental project confirms that these features must have been built through group effort. The marked concentration of large-scale trapping features in western and eastern Nevada may be explained by ecological factors such as the presence of migrating herds of ungulates, nearby toolstone sources, pinyon nuts, and water. The proliferation of large-scale trapping feature planning and construction beginning ca. 5000 to 6000 years ago is supported by studies of trap-associated projectile points and rock art. Initial construction of traps may have been sparked by human population increases that created new challenges and encouraged the development of new sociological and ecological adaptations.

Denial of Service (DoS) attacks are a type of interruption (malicious and/or unintended) that restrict or completely deny services meant for legitimate users. One of the most relevant DoS attacks is Distributed Denial of Service (DDoS) attack which is a variant of DoS, but on a larger scale using previously compromised, malware infected computers known as “bots” or “zombies”. DDoS attack occurs by generating large amounts of traffic towards an intended victim. This paper focuses on analyzing a variant of DDoS attacks known as Network Time Protocol (NTP) Distributed Reflective Denial of Service (DRDoS) attack. The impact of the attack will be measured in the utilization of processor, memory, network and ping of most relevant devices. Further focus is on the host and network based layered “defense in-depth” of NTP DRDoS attack mitigation techniques.

New psychoactive substances (NPS) have been associated with fatalities and severe injuries in a number of cases in the United States and have led investigators to rethink traditional drug monitoring protocols. Of particular interest are the variable phenethylamine chemical structures known as 'NBOMes', which pose an emerging threat to public health with incidence steadily growing over the past decade. In this study, direct sample analysis (DSA)-time of flight mass spectrometry was employed to leverage rapid and sensitive ambient ionization mass spectrometry without chromatographic separation as verified with an authentic case sample. Samples for method development were prepared at Boston University School of Medicine's Biomedical Forensic Sciences program (Boston, MA) and analyzed at the State of Maine Health and Environmental Testing Laboratory's Forensic Chemistry Section (Augusta, ME). Preliminary method development work was performed at the University of Central Florida (Orlando, FL). DSA without any extraction step in addition to the evaluation of methanol, dichloromethane and hexane extractions were conducted. Methanol was found to not be a suitable extraction solvent for DSA analysis of these compounds. For the screening of NBOMe designer drug variables on blotter paper, DSA-TOFMS was successful at reducing analysis time to ∼15s per sample, for qualitative identification for the selected analytes of interest. The analysis of an authentic forensic case sample by DSA-TOFMS using the method development parameters demonstrates its utility in forensic laboratories. 25C-NBOMe was identified with an exact mass accuracy of 0.60ppm.

Early Holocene adaptations are still poorly understood in North America. The archaeological record of this period is often difficult to access and most studies have taken a site-based approach, focused on a small number of well-excavated sites. The archaeological record of the Coso Basin in the northwest Mojave Desert provides the unique opportunity to approach adaptations from a landscape, rather than a site-based, perspective. Large sections of land that were formed during the Pleistocene and Early Holocene, the landforms on which Early Holocene hunter-gatherers lived, are still exposed and easily accessible today. Previous studies have significantly under-represented these landforms in regional survey and excavation. Our analyses suggest that Early Holocene people made use of a wide range of environments, not primarily lakes and wetlands as has commonly been suggested. Furthermore, there is little indication that populations were more residentially mobile and lived in lower population densities than later in time. After accounting for survey, geological, and temporal biases, it is apparent that site densities equal or exceed those of later periods in time. These findings should challenge archaeologists to reconsider certain notions about the Early Holocene in the desert west and to, when possible, take a landscape approach in reconstructing prehistoric lifeways.

In the nearshore zone of the Alaskan Beaufort Sea, three subsea pipeline bundles have been successfully installed by using conventional onshore construction equipment in the winter season operating from a thickened sea ice platform. Differences in water depth, route length and corresponding pipeline design for BP Northstar, Pioneer Oooguruk and Eni Nikaitchuq impacted the winter construction procedures used for each project. Each of these projects used the winter construction season to its maximum advantage, allowing the use of conventional and adapted onshore construction equipment and techniques. Comparatively, ice based winter pipeline construction in subarctic conditions has been generally less successful. On-ice pipeline fabrication and installation into a subsea trench has a track record for shallow water pipeline installation with reduced permitting issues compared to summer installation. Based on the experiences of these projects, this paper reviews the limitations of on-ice construction, the typical construction activities; the main equipment used and will highlight the main lessons learned.

The attraction of foreign direct investment (FDI) has become a major economic development goal of the postsocialist countries of East and Central Europe (ECE). ECE countries have rapidly adopted ‘Western’-style place-marketing policies to attract FDI. However, little is known about place marketing under postsocialism, and particularly in the context of an enlarged European Union; hence the author presents an analysis of the supply-side policies which Hungary has developed in response to its rapidly changing position with regard to FDI. In particular, he examines the strategies developed by two key agencies responsible for attracting inward investment, the Ministry of Economy and Transport and the Hungarian Investment and Trade Development Agency. Hungary’s current position in respect to patterns of attracting FDI is evaluated and, through outlining the key changes in the nature of FDI, a set of key issues which must be addressed in any place-marketing strategy in ECE is developed. The author then analyses how these two key agencies have responded to this new FDI context. The author assesses how Hungary has been able to address the new FDI context and also considers how FDI and attempts to attract it is reshaping supply-side policies, and postsocialist states themselves.

Critical thinking is often considered an essential learning outcome of institutions in higher education. Previous work has proposed three pedagogical strategies to address this goal: more active, student-centered in-class instruction, assessments which contain higher-order cognitive questions, and greater alignment within a classroom (i.e., high agreement of the cognitive level of learning objectives, assessments, and in-class instruction). Our goals were to determine which of these factors, individually or the interactions therein, contributed most to improvements in university students’ critical thinking. We assessed students’ higher-order cognitive skills in introductory non-majors biology courses the first and last week of instruction. For each of the fifteen sections observed, we also measured the cognitive level of assessments and learning objectives, evaluated the learner-centeredness of each classroom, and calculated an alignment score for each class. The best model to explain improvements in students’ high-order cognitive skills contained the measure of learner-centeredness of the class and pre-quiz scores as a covariate. The cognitive level of assessments, learning objectives, nor alignment explained improvements in students’ critical thinking. In accordance with much of the current literature, our findings support that more student-centered classes had greater improvements in student learning. However, more research is needed to clarify the role of assessment and alignment in student learning.

Numerous specimens of the majid spider crab,Encephaloides armstrongi, were sampled from six stations (populations) between 150 and 650 m depth, on the continental slope off the coast of Oman. This extended the known geographic and bathymetric range ofE. armstrongi, which is now known to occur along the continental margins of the northern Indian Ocean from the western coast of Burma to the coast of Oman. This band–like distribution is contiguous to the oxygen minimum zone in this region.The biology and genetics of populations ofEncephaloides armstrongiseparated by depth were studied. The overall sex ratio of theE. armstrongisampled was male–biased (p< 0.01; 3.3 males: 1 female;So= 0.538). However, sex ratio varied both between populations (p< 0.01) and between size classes of crabs. Size frequency analysis indicated that the male and female crabs consisted of at least two instars, one between 6 and 16 mm carapace length and one between 16 and 29 mm carapace length, which probably represented the terminal (pubertal) moult for most individuals. Accumulation of female crabs in the terminal instar probably caused the variation of sex ratio with size classes. Some male crabs grew to a larger size (up to 38 mm carapace length), possibly as a result of maturity at later instars.Length frequency distribution was significantly different between sexes (one–way ANOVAp< 0.001). Within sexes, length frequency distributions varied between different populations. In both male and femaleEncephaloides armstrongithe individuals from a single population located at 150 m depth were significantly smaller than individuals at all other stations and were considered to represent a juvenile cohort. For female crabs no other significant differences were detected in length frequency between populations from 300 m to 650 m depth. Significant differences in length frequency were detected between male crabs from populations between 300 and 650 m depth.Horizontal starch gel electrophoresis was used to detect six enzyme systems coding for eight loci for individuals sampled from each population ofEncephaloides armstrongi. Genetic identity (I) values between populations ofE. armstrongi(I= 0.98−1.00) were within the normal range for conspecific populations. Observed heterozygosity (Ho= 0.080−0.146) was lower than expected heterozygosity (He= 0.111−0.160), but in the normal range detected for eukaryotic organisms.F–statistics were used to analyse between population (FST) and within population (F) genetic structure. For both male and femaleE. armstrongisignificant genetic differentiation was detected between the population located at 150 m depth and all other populations. Analyses ofFISandFST, excluding the 150 m population indicated that for femaleE. armstrongithere was no significant structuring within or between populations. For maleE. armstrongisignificant heterozygote deficiencies were detected within populations and significant genetic differentiation between populations.The most likely explanations for the observations of the present study are: the population ofEncephaloides armstrongilocated at 150 m depth represented a juvenile cohort that is genetically distinct from deeper populations; femaleE. armstrongiformed a single population between 300 m and 650 m depth in the sampling area; maleE. armstrongiwere from two or more genetically distinct populations which are represented by different numbers of individuals at stations between 300 m and 650 m depth. This caused the observed significant differences in morphology (size distribition) and allele frequencies of male populations. It is likely thatE. armstrongiexhibits gender–biased dispersal and that the crabs collected between 300 m and 650 m depth formed spawning aggressions. This also explains the bias in sex ratio of individuals sampled in the present study.

This issue provides a clinical overview of plantar fasciitis focusing on prevention, diagnosis, treatment, practice improvement, and patient information. Readers can complete the accompanying CME quiz for 1.5 credits. Only ACP members and individual subscribers can access the electronic features of In the Clinic. Non-subscribers who wish to access this issue of In the Clinic can elect "Pay for View." Subscribers can receive 1.5 category 1 CME credits by completing the CME quiz that accompanies this issue of In the Clinic. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including PIER (Physicians' Information and Education Resource) and MKSAP (Medical Knowledge and Self Assessment Program). Annals of Internal Medicine editors develop In the Clinic from these primary sources in collaboration with the ACP's Medical Education and Publishing division and with assistance of science writers and physician writers. Editorial consultants from PIER and MKSAP provide expert review of the content. Readers who are interested in these primary resources for more detail can consult www.acponline.org, http://pier.acponline.org, and other resources referenced within each issue of In the Clinic.