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We present a sediment-mixing process model of till genesis based on data from surface tills of the Saginaw lobe terrain in lower Michigan. Our research uses a spatial approach to understanding glacial landsystems and till genesis. We sampled calcareous till at 336 upland sites and at 17 sites in lacustrine sediment of the Saginaw Lake plain. The loamy tills have bimodal grain-size curves, with a fine-texture mode near the silt–clay boundary and a sand mode. Spatial grouping analysis suggests that tills can be divided into six groups, each with different textures and clay mineral compositions that vary systematically down-ice. The similarity among groups with respect to the silt–clay mode and clay mineralogy argues for a common origin for the fines—illite-rich lacustrine sediment of the Saginaw Lake plain. Fine-textured sediments were probably entrained, transported, and deposited down-ice as till, which also becomes sandier and enriched in kaolinite, reflecting increasing mixing with shallow sandstone bedrock with distance from the lacustrine clay source. Clayey tills on the flanks of the Saginaw terrain may reflect proglacial ponding against nearby uplands. A process model of progressive down-ice mixing of preexisting fine lake sediments with crushed/abraded sandstone bedrock helps to better explain till textures compared with a purely crushing/abrasion process model.
Diverse theoretical perspectives suggest that place plays an important role in human behavior. One recent perspective proposes that habitual and recursive use of places among humans may be an emergent property of obligate tool use by our species. In this view, the costs of tool use are reduced by preferential occupation of previously occupied places where cultural materials have been discarded. Here we use the model to generate five predictions for ethnographic mobility patterns. We then test the predictions against observations made during one month of coresidence with a residentially mobile Dukha family in the Mongolian Taiga. We show that (1) there is a strong tendency to occupy previously used camps, (2) previously deposited materials are habitually recycled, (3) reoccupation of places transcends kinship, (4) occupational hiatuses can span decades or longer, and (5) the distribution of occupation intensity among camps is highly skewed such that most camps are not intensively reoccupied whereas a few camps experience extremely high reoccupation intensity. These findings complement previous archaeological findings and support the conclusion that the constructed dimensions of human habitats exert a strong influence on mobility patterns in mobile societies.
In several recently published phylogenetic analyses, two Lower Devonian taxa, Doliodus and Pucapampella, both fall on the chondrichthyan stem, very close to the base of ‘conventionally defined chondrichthyans’ (i.e., forms possessing tessellated mineralization of the cartilaginous endoskeleton). These two taxa nevertheless exhibit strongly discordant morphologies from each other. A summary of the anatomical data concerning these taxa is presented here, including new, as well as previously published, findings. A new family Pucapampellidae is erected, containing Pucapampella and a newly recognized genus from South Africa. Morphological evidence is summarized for the monophyly of crown elasmobranchs (sharks and rays), holocephalans (chimaeras) and other chondrichthyans. Based on these data, Doliodus and pucapampellids both fall outside the chondrichthyan crown, but their relative phylogenetic positions on the chondrichthyan stem are unclear. Pucapampellid interrelationships are particularly hard to assess because little is known beyond their cranial and visceral arch morphology and also because pucapampellids possess a suite of ontogenetically primitive (and thus potentially neotenic) features. By contrast, the phylogenetic position of Doliodus seems less elusive; it possessed an ‘acanthodian-like’ complex of dermal spines, including pectoral fin spines, prepectoral, admedian, and prepelvic spines, and possibly dorsal and pelvic fin spines, in conjunction with numerous ‘chondrichthyan-like’ endoskeletal features and a heterodont ‘sharklike’ dentition. Doliodus can be viewed as a quintessential component of the evolutionary transition between ‘acanthodians’ and ‘conventionally defined chondrichthyans’, leaving little doubt that the chondrichthyan total group includes ‘acanthodians’ (now widely perceived to be a paraphyletic group, populating the basal part of the chondrichthyan stem). Although Doliodus has been resolved as a basal member of the ‘conventionally defined chondrichthyans’, it could occupy a more basal position on the chondrichthyan stem.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.
This Research Communication describes an investigation of the nutritional depletion of total mixed rations (TMR) by pest birds. We hypothesized that species-specific bird depredation of TMR can alter the nutritional composition of the ration and that these changes can negatively impact the performance of dairy cows. Blackbirds selected the high energy fraction of the TMR (i.e., flaked corn) and reduced starch, crude fat and total digestible nutrients during controlled feeding experiments. For Holsteins producing 37·1 kg of milk/d, dairy production modeling illustrated that total required net energy intake (NEI) was 35·8 Mcal/d. For the reference TMR unexposed to blackbirds and the blackbird-consumed TMR, NEI supplied was 41·2 and 37·8 Mcal/d, and the resulting energy balance was 5·4 and 2·0 Mcal/d, respectively. Thus, Holsteins fed the reference and blackbird-consumed TMR were estimated to gain one body condition score in 96 and 254 d, and experience daily weight change due to reserves of 1·1 and 0·4 kg/d, respectively. We discuss these results in context of an integrated pest management program for mitigating the depredation caused by pest birds at commercial dairies.
In September 2016, the annual meeting of the International Union for Quaternary Research’s Loess and Pedostratigraphy Focus Group, traditionally referred to as a LoessFest, met in Eau Claire, Wisconsin, USA. The 2016 LoessFest focused on “thin” loess deposits and loess transportation surfaces. This LoessFest included 75 registered participants from 10 countries. Almost half of the participants were from outside the United States, and 18 of the participants were students. This review is the introduction to the special issue for Quaternary Research that originated from presentations and discussions at the 2016 LoessFest. This introduction highlights current understanding and ongoing work on loess in various regions of the world and provides brief summaries of some of the current approaches/strategies used to study loess deposits.
Our primary goal was to decrease time to resolution of postoperative chylothorax as demonstrated by total days of chest tube utilisation through development and implementation of a management protocol.
A chylothorax management protocol was implemented as a quality improvement project at a tertiary-care paediatric hospital in July, 2015. Retrospective analysis was completed on patients aged 0–17 years diagnosed with chylothorax within 30 days of cardiac surgery in a pre-protocol cohort (February, 2014 to June, 2015, n=20) and a post-protocol cohort (July, 2015 to March, 2016, n=22).
Measurements and results
Patient characteristics were similar before and after protocol implementation. Duration of mechanical ventilation and cardiac ICU and hospital lengths of stay were unchanged between cohorts. Following protocol implementation, total duration of chest tube utilisation decreased from 12 to 7 days (p=0.047) with a decrease in maximum days of chest tube utilisation from 44 to 13 days. Duration of medium-chain triglyceride feeds decreased from 42 days to 31 days (p=0.01). In total, three patients in the post-protocol cohort underwent additional surgical procedures to treat chylothorax with subsequent resolution of chylothorax within 24 hours. There were no chest tube re-insertions or re-admissions related to chylothorax in either the pre- or post-protocol cohorts. Protocol compliance was 81%.
Adoption of a chylothorax management protocol is feasible, and in our small cohort of patients implementation led to a significant decrease in the duration of chest tube utilisation, while eliminating practice variability among providers.
Two new species of Schramocaris from the Viséan, Lower Carboniferous of Scotland and eastern Canada extend the range and distribution of this crustacean along the northwestern coast of the Rheic Ocean. New species from Glencartholm, southern Scotland and Upperton, New Brunswick, Canada represents the first recognised occurrence of this genus in Scotland and Canada. The Scottish species is here named S. clarksoni; it lacks the rugosity of the carinae of Schramocaris gilljonesorum, but has the same relative position of the carinae, as well as similar characteristics of the pleon, such as the relative lengths of the somites and the shape of the telson. The Canadian species is named Schramocaris matthewi on the basis of the papillations on the cuticle and robust second carinae of the carapace. The deposits at both these localities are that of a shallow marine argillaceous environment, although the Glencartholm deposit contains more lime. Schramocaris has previously only been known from the Avon Group (Hastarian) of the Forest of Dean, England.
There is a growing concern about the role of the environment in the dissemination of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARG). In this systematic review, we summarize evidence for increases of ARG in the natural environment associated with potential sources of ARB and ARG such as agricultural facilities and wastewater treatment plants. A total of 5247 citations were identified, including studies that ascertained both ARG and ARB outcomes. All studies were screened for relevance to the question and methodology. This paper summarizes the evidence only for those studies with ARG outcomes (n = 24). Sixteen studies were at high (n = 3) or at unclear (n = 13) risk of bias in the estimation of source effects due to lack of information or failure to control for confounders. Statistical methods were used in nine studies; three studies assessed the effect of multiple sources using modeling approaches, and none reported effect measures. Most studies reported higher ARG concentration downstream/near the source, but heterogeneous findings hindered making any sound conclusions. To quantify increases of ARG in the environment due to specific point sources, there is a need for studies that emphasize analytic or design control of confounding, and that provide effect measure estimates.
Our study adds to the Quaternary history of eolian systems and deposits in western Wisconsin, USA, primarily within the lower Chippewa River valley. Thickness and textural patterns of loess deposits in the region indicate transport by west-northwesterly and westerly winds. Loess is thickest and coarsest on the southeastern flanks of large bedrock ridges and uplands, similar in some ways to shadow dunes. In many areas, sand was transported up and onto the western flanks of bedrock ridges as sand ramps, presumably as loess was deposited in their lee. Long, linear dunes, common on the sandy lowlands of the Chippewa valley, also trend to the east-southeast. Small depressional blowouts are widespread here as well and often lie immediately upwind of small parabolic dunes. Finally, in areas where sediment was being exposed by erosion along cutbanks of the Chippewa River, sand appears to have been transported up and onto the terrace treads, forming cliff-top dunes. Luminescence data indicate that this activity has continued throughout the latest Pleistocene and into the mid-Holocene. Together, these landforms and sediments paint a picture of a locally destabilized landscape with widespread eolian activity throughout much of the postglacial period.
The Association of American Medical Colleges recommended an increase in medical education for public health emergencies, bioterrorism, and weapons of mass destruction in 2003. The University of South Dakota Sanford School of Medicine (USD SSOM) implemented a 1-day training event to provide disaster preparedness training and deployment organization for health professions students called Disaster Training Day (DTD).
Hospital staff and emergency medical services personnel provided the lecture portion of DTD using Core Disaster Life Support (CDLS; National Disaster Life Support Foundation) as the framework. Pre-test and post-test analyses were presented to the students. Small group activities covered leadership, anaphylaxis, mass fatality, points of dispensing deployment training, psychological first aid, triage, and personal protective equipment. Students were given the option to sign up for statewide deployment through the South Dakota Statewide Emergency Registry of Volunteers (SERV SD). DTD data and student satisfaction surveys from 2009 to 2016 were reviewed.
Since 2004, DTD has provided disaster preparedness training to 2246 students across 13 health professions. Significant improvement was shown on CDLS post-test performance with a t-score of −14.24 and a resulting P value of <0.00001. Students showed high levels of satisfaction on a 5-level Likert scale with overall training, small group sessions, and perceived self-competency relating to disaster response. SERV SD registration increased in 2015, and 77.5% of the participants registered in 2016.
DTD at the USD SSOM provides for an effective 1-day disaster training course for health professions students. Resources from around the state were coordinated to provide training, liability coverage, and deployment organization for hundreds of students representing multiple health professions. (Disaster Med Public Health Preparedness. 2017;11:735–740)
We describe the design and performance of the Engineering Development Array, which is a low-frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased array. The Engineering Development Array was conceived of, developed, and deployed in just 18 months via re-use of Square Kilometre Array precursor technology and expertise, specifically from the Murchison Widefield Array radio telescope. Using drift scans and a model for the sky brightness temperature at low frequencies, we have derived the Engineering Development Array’s receiver temperature as a function of frequency. The Engineering Development Array is shown to be sky-noise limited over most of the frequency range measured between 60 and 240 MHz. By using the Engineering Development Array in interferometric mode with the Murchison Widefield Array, we used calibrated visibilities to measure the absolute sensitivity of the array. The measured array sensitivity matches very well with a model based on the array layout and measured receiver temperature. The results demonstrate the practicality and feasibility of using Murchison Widefield Array-style precursor technology for Square Kilometre Array-scale stations. The modular architecture of the Engineering Development Array allows upgrades to the array to be rolled out in a staged approach. Future improvements to the Engineering Development Array include replacing the second stage beamformer with a fully digital system, and to transition to using RF-over-fibre for the signal output from first stage beamformers.
Timing of weed emergence and seed persistence in the soil influence the ability to implement timely and effective control practices. Emergence patterns and seed persistence of kochia populations were monitored in 2010 and 2011 at sites in Kansas, Colorado, Wyoming, Nebraska, and South Dakota. Weekly observations of emergence were initiated in March and continued until no new emergence occurred. Seed was harvested from each site, placed into 100-seed mesh packets, and buried at depths of 0, 2.5, and 10 cm in fall of 2010 and 2011. Packets were exhumed at 6-mo intervals over 2 yr. Viability of exhumed seeds was evaluated. Nonlinear mixed-effects Weibull models were fit to cumulative emergence (%) across growing degree days (GDD) and to viable seed (%) across burial time to describe their fixed and random effects across site-years. Final emergence densities varied among site-years and ranged from as few as 4 to almost 380,000 seedlings m−2. Across 11 site-years in Kansas, cumulative GDD needed for 10% emergence were 168, while across 6 site-years in Wyoming and Nebraska, only 90 GDD were needed; on the calendar, this date shifted from early to late March. The majority (>95%) of kochia seed did not persist for more than 2 yr. Remaining seed viability was generally >80% when seeds were exhumed within 6 mo after burial in March, and declined to <5% by October of the first year after burial. Burial did not appear to increase or decrease seed viability over time but placed seed in a position from which seedling emergence would not be possible. High seedling emergence that occurs very early in the spring emphasizes the need for fall or early spring PRE weed control such as tillage, herbicides, and cover crops, while continued emergence into midsummer emphasizes the need for extended periods of kochia management.