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Background Immune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts and increased risk of bleeding. In preparation for an upcoming guideline, the ITP Emergency Management Guideline Panel, including clinical experts in hematology, emergency medicine, research methodology, and patient representatives, identified the need for a standardized definition of a critical ITP bleed. The goal of the definition was to distinguish critical bleeds from bleeds that may not require urgent treatment, typically in the context of severe thrombocytopenia. Methods The panel met in person and virtually to achieve consensus on the criteria for critical bleeding events among patients with ITP. Existing ITP bleeding scores and published definitions of major bleeds in patients receiving anticoagulation informed the definition of a critical ITP bleed. The Platelet Immunology Scientific Standardization Committee (SSC) of the International Society on Thrombosis and Haemostasis endorsed the definition. Results A critical ITP bleed was defined as: (a) a bleed in a critical anatomical site including intracranial, intraspinal, intraocular, retroperitoneal, pericardial, or intramuscular with compartment syndrome; or (2) an ongoing bleed that results in hemodynamic instability or respiratory compromise. Conclusion The definition of a critical ITP bleed was developed by the ITP Emergency Management Guideline Panel and endorsed by the Platelet Immunology SSC. It incorporates both anatomic and physiologic risk and pertains to patients with confirmed or suspected ITP who typically have severe thrombocytopenia (platelet count below 20 × 109 /L).

Background Appropriate documentation of critical care services, including key time-based parameters, is critical to accurate severity of illness metrics and proper reimbursement. Documentation of time-based elements for critical care services performed in emergency departments (ED) remains inconsistent. We integrated electronic medical record and real-time location system (RTLS)-derived data to augment quality improvement methodology. Objective We aimed to increase the proportion of patient encounters with critical care services performed at a pediatric ED that had appropriate documentation from a baseline of 76 to 90% within 6 weeks. Methods The team formulated a framework of improvement and performed multiple plan-do-study-act cycles focused on key drivers. We integrated the capabilities of an RTLS for precise location tracking to identify patient encounters in which critical care services were performed and to minimize unnecessary audits and feedback. We developed an intervention using iterative revisions to address key drivers and improve documentation. The primary outcome was the proportion of patient encounters for which critical care services were performed for which a time-based attestation was documented in the medical record. Results We analyzed 92 encounters between March 2020 and April 2020. While the proportion of eligible patient encounters with critical care documentation improved from 76 to 85%, this change was unable to be directly attributed to improvement efforts. Patients with respiratory complaints encompassed the majority of eligible encounters without appropriate documentation. Conclusion Utilizing improvement methodology and a novel application of RTLS, we successfully identified the co-location of physicians with patients receiving critical care services and designed interventions to improve documentation of critical care services provided in a pediatric ED. While changes were not able to be attributed to improvement efforts in this project, this project demonstrates the utility of RTLS to augment and inform systematic improvement efforts.

Supplemental Digital Content is available in the text., Introduction: Primary headache is a common cause of pediatric emergency department (PED) visits. Without published guidelines to direct treatment options, various strategies lacking evidence are often employed. This study aims to standardize primary headache treatment in the PED by promoting evidence-based therapies, reducing nonstandard abortive therapies, and introducing dihydroergotamine (DHE) into practice. Methods: A multidisciplinary team developed key drivers, created a clinical care algorithm, and updated electronic medical record order sets. Outcome measures included the percentage of patients receiving evidence-based therapies, nonstandard abortive therapies, DHE given after failed first-line therapies, and overall PED length of stay. Process measures included the percent of eligible patients with the order set usage and medications received within 90 minutes. Balancing measures included hospital admissions and returns to the PED within 72 hours. Annotated control charts depicted results over time. Results: We collected data from July 2017 to December 2019. The percent of patients receiving evidence-based therapies increased from 69% to 73%. The percent of patients receiving nonstandard abortive therapies decreased from 2.5% to 0.6%. The percent of patients receiving DHE after failed first-line therapies increased from 0% to 37.2%. No untoward effects on process or balancing measures occurred, with sustained improvement for 14 months. Conclusion: Standardization efforts for patients with primary headaches led to improved use of evidence-based therapies and reduced nonstandard abortive therapies. This methodology also led to improved DHE use for migraine headache resistant to first-line therapies. We accomplished these results without increasing length of stay, admission, or return visits.

We aimed to develop machine learning models to accurately predict bronchiolitis severity, and to compare their predictive performance with a conventional scoring (reference) model. In a 17-center prospective study of infants (aged

Study objective This study sought to determine whether a brief intervention at the time of emergency department (ED) discharge can improve safe dosing of liquid acetaminophen and ibuprofen by parents or guardians. Methods We performed a randomized controlled trial in the ED of parents and guardians of children 90 days to 11.9 years of age who were discharged with acetaminophen or ibuprofen, or both. Families were randomized to standard care or a teaching intervention combining lay language, simplified handouts, provision of an unmarked dosing syringe, and teach-back to confirm correct dosing. Participants were called 48 to 72 hours and 5 to 7 days after ED discharge to assess understanding of correct dosing. The primary outcome was defined as parent or guardian report of safe dosing at the time of first follow-up call. Our primary hypothesis was that the intervention would decrease the rate of error from 30% to 10% at 48- to 72-hour follow-up. Results We enrolled 149 of 259 (58%) eligible subjects; 97 of 149 (65%) were reached at first follow-up call, of whom 35 of 97 (36%) received the intervention. Among those participants receiving the intervention, 25 of 35 (71%) were able to identify a safe dose for their child at the time of the first call compared with 28 of 62 (45%) of those in the control arm. The difference in proportions was 26% (95% confidence interval [CI] 7% to 46%). There was a 58% increase in reporting safe dosing in the intervention group compared with the control roup (relative risk 1.58; 95% CI 1.12 to 2.24), and it remained significant after adjustment for health literacy and language (adjusted relative risk 1.50; 95% CI 1.06 to 2.13). Conclusions A multifaceted intervention at the time of ED discharge—consisting of a simplified dosing handout, a teaching session, teach-back, and provision of a standardized dosing device—can improve parents’ knowledge of safe dosing of liquid medications at 48 to 72 hours.

IVIG has been the predominant therapy for the initial management of children with newly diagnosed immune thrombocytopenia at our hospital. With current guidelines supporting more conservative management, we undertook a quality improvement initiative to lead practice change. Over a 2-year time period (2013 to 2015), we strove to decrease use of hospital resources (use of IVIG, length of stay) while optimizing family satisfaction. An interdisciplinary working group was struck and a quality improvement bundle was implemented. The bundle comprised a patient information sheet; an evidence-informed, consensus-based protocol; and promotion of shared decision-making via stakeholder engagement and education. Data were collected prospectively; baseline data from a 2007 to 2009 audit were used for comparison. In total, 27 patients were included. Mean initial platelet count was 4×10/L. Bleeding was classified as none or mild in 56% of patients. IVIG use decreased from 88% to 55% of patients, corticosteroid prescription increased from 6% to 15%, and observation increased from 6% to 30% of patients. Hospital length of stay decreased from 47 to 36 hours. Family satisfaction was stable across treatment groups. Through introduction of a quality improvement initiative, we were able to improve family-centered care and decrease use of hospital resources.

This study combined multiple aquatic and terrestrial proxies, including diatoms, pollen, grain size, and bulk-sediment chemistry to reconstruct the history of three lake sites located in the central Sand Hills of Nebraska, USA. Long-term changes in effective moisture are evident at all sites, with significant changes occurring at ~6000, ~4000, and ~ 2000 cal. yr BP. Both aquatic and terrestrial indicators suggest that effective moisture was low between 10,000 and ~6000 cal. yr BP, and that this time interval was the driest period of the Holocene. The dominance of benthic and tychoplanktic diatom taxa indicates relatively shallow lake-level, high sand influx indicates moderately high eolian activity, and the pollen assemblage suggests xeric grasslands with abundant mud flats. About 6000 cal. yr BP, all three sites experienced an increase in effective moisture. Lake-level rise is indicated by increases in planktic and tychoplanktic diatoms relative to benthic taxa, while greater abundance of grass pollen and charcoal, and decreased eolian flux indicate stabilized dunes with dense vegetation sufficient to fuel local fires. A significant hydrologic shift recorded at all sites occurred at ~4000 cal. yr BP. This event was characterized by substantial lake-level rise, yet decreased grass cover and fire frequency, and increased eolian activity. Water-table rise may have been caused by a combination of factors including: (1) formation of dune-dams that blocked old drainage channels, (2) reduced grass cover and hence reduced evapotranspiration, and (3) changes in the frequency and duration of drought. The most likely cause(s) of the differential response of the terrestrial and aquatic systems at this time is not clear, none-the-less the late Holocene was not nearly as dry as the interval prior to 6000 cal. yr BP. The last ~2000 yr were characterized by several short-term fluctuations in lake level, including an interval of drought between 950 and 750 cal. yr BP, coincident with increased eolian activity during the latter part of the Medieval Climatic Anomaly.

OBJECTIVE We investigated the potential value of information shared by parents on a written form designed to capture needs and expectations for care to an emergency department (ED) system that values patient-centeredness. METHODS We conducted a retrospective content analysis of parent-completed written forms collected during an improvement project focused on parent-provider communication in a pediatric ED. The primary outcome was potential value of the completed forms to a patient-centered ED system, defined as a form that was legible, included observations that mapped to medical problems, and included reasonable parental requests. We analyzed variation in potential value and other form attributes across a priori-defined visit type and acuity. Visit type was validated by a separate, blinded medical record review. RESULTS A random stratified sample of 1008 forms was established from 6937 parent-completed forms collected during the 6-month improvement project; 995 of 1008 forms had matching medical records; 922 (92.7%) of 995 forms demonstrated potential value; 990 (99.5%) of 995 forms were legible; 948 (95.3%) of 995 forms included observations that mapped to a medical problem, and 599 (93.3%) of 642 forms contained reasonable parental requests. There was good agreement between the form and medical record for visit type (κ = 0.62). The potential value of forms did not vary significantly across visit type (88.2%-92.8%) or acuity (88.9%-93.4%). CONCLUSIONS Information shared by parents on written forms designed to capture needs and expectations provides potential value to a patient-centered ED system. The high level of informational value is consistent across patient type and acuity level.

Objective: We implemented and evaluated a quality improvement initiative targeting parents' communication with clinicians in a pediatric emergency department (ED). Methods: A quality improvement initiative ("Clear and Concise Communication" or "3C") targeting parent-provider communication was implemented in an urban tertiary care pediatric ED. A 1-page form that solicited parent worries, questions, and expectations for care was developed. Parent-provider communication was measured using an 8-item subset of questions from an ongoing satisfaction survey adopted for pediatric emergency care. The primary outcome was the communication score for a given ED visit scaled from 0 to 100 and was calculated as the simple average of answers where the best possible response was given a value of 1 and all others were scored as 0. A multivariate model adjusting for time-related factors, ED volume, and system-level events was developed to examine the influence of the communication initiative. Results: A total of 29,005 patients received care during implementation of 3C; a total of 100,810 patients received care during the 2-year period of interest. Data from 1233 satisfaction surveys were used to create the communication scores. Communication scores ranged from 0 to 100, with a mean of 88 and SD of 17.7. In a linear model adjusting for day, weekend, volume, system-level introduction of electronic charting for nurses, and electronic-order entry for physicians, the 3C initiative demonstrated a positive and statistically significant effect—increasing the communication score by 2.8 points/100 d (95% confidence interval, 0.1-5.5). Conclusions: The 3C initiative succeeded in improving parents' communication experience with emergency providers during the intervention period.

BACKGROUND: The true rate of neurologic sequelae and infection from penetrating palatal trauma in children is unknown, which leads to significant variation in testing and treatment. OBJECTIVES: To (1) determine the incidence of stroke and infection in well-appearing children with penetrating palatal trauma and (2) describe patterns of testing and treatment for uncomplicated palatal trauma. METHODS: We assembled a retrospective cohort of children aged 9 months to 18 years with palatal trauma seen in the emergency department (ED) at a tertiary care pediatric hospital. Patients met the following definition: well-appearing with normal neurologic examination and a palate laceration but no findings requiring immediate operative care. Stroke was defined as any abnormal neurologic examination secondary to palatal trauma. Infection was defined as cellulitis or abscess secondary to palatal injury. All abnormal computed tomographic angiography (CTA) findings, except for free air, were considered positive and potentially significant. RESULTS: We identified 1656 potential subjects. A total of 995 of 1656 subjects were screened, and 205 of 995 met the case definition. A total of 122 of 205 had follow-up through at least 1 week after injury. The incidence of stroke in our study population was 0% (95% confidence interval [CI]: 0–2.5). One of 116 patients developed infection, for an incidence of 0.9% (95% CI: 0–5.3). A total of 90 of 205 (44%) subjects had CTA scans; the results of 9 (10%) were positive. No patients with positive CTA findings required operative care. No patients received anticoagulant medications. CONCLUSIONS: The incidence of morbidity from penetrating palatal trauma in the well-appearing child is extremely low. Diagnostic evaluation in the ED did not prompt clinical interventions other than antibiotics.

Objective The aim of this study was to determine the impact of a patient-centered health information technology (HIT) on the error rate for ordering and prescribing of medications during emergency pediatric care. Methods We conducted a quasi-experimental intervention study by using control and intervention periods to evaluate the effect on medication ordering and prescribing from a patient-centered HIT designed to enhance communication between parents and emergency clinicians during emergency care. Parent-child dyads presenting to 2 emergency department (ED) sites with complaints of fever, asthma, head trauma, otalgia, and dysuria were eligible. During intervention periods, parents used the HIT to enter data on symptoms and medication-related history; a printout provided recommendations to clinicians. Data on errors/adverse drug events were collected via record reviews and phone interviews with parents. The primary outcome was the number of medication errors in orders or prescriptions for drugs targeted by the HIT. Results Of 2002 parent-child dyads screened, 1810 (90%) were eligible, 1411 of 1810 (78%) were enrolled, and 1410 analyzed; 1097 subjects had a total of 2234 orders or prescriptions written. Of these events, 1289 of 2234 (58%) were associated with at least 1 error. Of the 1755 errors discovered, 232 errors were serious and preventable. Among 654 patients exposed to medications targeted by the HIT, the number of errors per 100 patients during control versus intervention periods was not significantly different (173 vs 134 with both sites combined; P = .35.) Conclusion The patient-centered HIT demonstrated minimal impact on medication errors during ED care.

and are more degraded. Seventy-six 36 Cl dates for the moraines cluster in groups having mean ages ( 1) of 12,500 500, 13,300 800, 16,100 1100, 19,100 3000, 70,900 1500, 93,100 2600, and 105,400 2200 years; a still-older, highly weathered and eroded moraine is undated, but likely is at least 165,000 years old. The moraine ages and relative extent of the Icicle Creek glacier correspond closely to the ages and relative amplitude of July insolation minima at 47.5° N latitude. They also are in accord with ages for glaciations in the European Alps that were inferred by Milutin Milankovitch and colleagues in the 1920s based on calculations of summer insolation. Evidence that the greatest Late Pleistocene glacier advance occurred at the onset of the last glaciation (during marine isotope substage 5d) is consistent with a cooling climate and major glacier advances at that time elsewhere in North America and the Eurasian Arctic, with a dramatic increase in global ice volume, and with the shifting track of the jet stream over northwestern United States.

The heavy mineral content of volcanic ash from Mount Mazama (layer O) and Mount St. Helens (layer Yn) decreases downwind from each volcano. The transparent heavy mineral suite of layer O also varies downwind because of differences in specific gravity and shape of the grains, reflecting sorting processes during transportation in the atmosphere. In the first few tens of kilometers from the volcano some values strongly deviate from the general trend. This is attributed to exceptional turbulence at the time of eruptions in the vicinity of the vent., Le contenu en minéraux denses a été étudié dans des échantillons provenant de deux retombées volcaniques largement répandues sur le nord-ouest des États-Unis et sur le sud-ouest du Canada. L'une d'entre elles correspond à l'explosion du mont Mazama (Oregon) survenue il y a environ 6700 ans; elle est connue sous le nom de « couche O ». L'autre résulte d'une explosion du mont St. Helens qui a eu lieu il y a environ 3400 ans; elle est connue sous le nom de « couche Yn ». Dans chacun des deux lobes, le contenu en minéraux denses diminue avec la distance aux volcans respectifs, et des variations spatiales systématiques de l'association de minéraux denses transparents dans le lobe de la « couche O » ont été mises en évidence. Ces variations sont comparées à celles qui ont été observées dans les retombées récentes des volcans mont St. Helens (É.-U., 18 mai 1980) et El Chichôn (Mexique, mars-avril 1982). Elles sont expliquées par des processus de sélection qui ont lieu dans les nuages de poussières au cours du transport dans l'atmosphère., In Proben, die aus zwei ausgedehnten vulkanischen Niederschlàgen im Nord-Westen der U.S.A. und dem Sùd-Westen Kanadas stammen, wurde der Gehalt an dichten Mineralen studiert. Der eine Niederschlag entspricht dem Ausbruch des Mount Mazama (Oregon), der vor etwa 6700 Jahren stattgefunden hat; er ist unter der Bezeichnung "Schicht O" bekannt. Der andere entstammt einem Ausbruch des Mount St. Helens, der vor ungefàhr 3400 Jahren stattgefunden hat ; er ist unter der Bezeichnung "Schicht Yn" bekannt. In jedem der zwei Ausschnitte nimmt der Gehalt an dichten Mineralen ab, entsprechend zur Entfernung zum jeweiligen Vulkan, und im Ausschnitt der "Schicht O" konnten systematische ôrtliche Schwankungen in der Assoziation der transparenten dichten Minérale nachgewiesen werden. Dièse Schwankungen werden verglichen mit denen, die in den neueren Niederschlagen der Vulkane von Mount St. Helens (U.S.A., 18. Mai 1980) und El Chichôn (Mexiko, Màrz-April 1982) beobachtet wurden. Sie werden erklàrt durch Selektionsprozesse, die in den Staubwolken wàhrend des Transports in der Atmosphère stattgefunden haben.

Objective: To determine the accuracy of self-reported information from patients and families for use in a disease surveillance system. Design: Patients and their parents presenting to the emergency department (ED) waiting room of an urban, tertiary care children's hospital were asked to use a Self-Report Tool, which consisted of a questionnaire asking questions related to the subjects' current illness. Measurements: The sensitivity and specificity of three data sources for assigning patients to disease categories was measured: the ED chief complaint, physician diagnostic coding, and the completed Self-Report Tool. The gold standard metric for comparison was a medical record abstraction. Results: A total of 936 subjects were enrolled. Compared to ED chief complaints, the Self-Report Tool was more than twice as sensitive in identifying respiratory illnesses (Rate ratio (RR): 2.10, 95% confidence interval (CI) 1.81- 2.44), and dermatological problems (RR: 2.23, 95% CI 1.56 -3.17), as well as significantly more sensitive in detecting fever (RR: 1.90, 95% CI 1.67-2.17), gastrointestinal problems (RR: 1.10, 95% CI 1.00 -1.20), and injuries (RR: 1.16, 95% CI 1.08 -1.24). Sensitivities were also significantly higher when the Self-Report Tool performance was compared to diagnostic codes, with a sensitivity rate ratio of 4.42 (95% CI 3.45-5.68) for fever, 1.70 (95% CI 1.49 - 1.93) for respiratory problems, 1.15 (95% CI 1.04 -1.27) for gastrointestinal problems, 2.02 (95% CI 1.42-2.87) for dermatologic problems, and 1.06 (95% CI 1.01-1.11) for injuries. Conclusions: Disease category assignment based on patient-reported information was significantly more sensitive in correctly identifying a disease category than data currently used by national and regional disease surveillance systems.

Eighteen radiocarbon-dated eolian and paleosol profiles within a 1500-km-long belt along the arid to semi-arid transition zone of north-central China record variations in the extent and strength of the East Asian summer monsoon during the Holocene. Dated paleosols and peat layers represent intervals when the zone was dominated by a mild, moist summer monsoon climate that favored pedogenesis and peat accumulation. Brief intervals of enhanced eolian activity that resulted in the deposition of loess and eolian sand were times when strengthened winter monsoon conditions produced a colder, drier climate. The monsoon variations correlate closely with variations in North Atlantic drift-ice tracers that represent episodic advection of drift ice and cold polar surface water southward and eastward into warmer subpolar water. The correspondence of these records over the full span of Holocene time implies a close relationship between North Atlantic climate and the monsoon climate of central China.

High volcanoes on two of the southeastern Hawaiian Islands experienced Pleistocene ice-cap glaciations. Drifts of three glaciations on the upper slopes of Mauna Kea (4206 m) are interstratified with lavas. During marine isotope stage (MIS) 2, an ice cap (70.5 km2) formed when the snowline fell ca. 930 m to an altitude of ca. 3785 m. Drifts of MIS 4 and 6 age, largely buried by hawaiite lavas, record a snowline about 100 m lower. Holocene lavas bury the upper slopes of Mauna Loa (4169 m), the summit of which likely intersected the snowline during the last glaciation. The reconstructed history of snowline variations and glaciation on Maui's Haleakala (3055 m) relies on evidence of the island's growth, isostatic subsidence, and tilting. The snowline may first have intersected Haleakala about 800,000 years ago; ice caps waxed and waned during the next ca. 400,000 years (MIS 22-12) until subsidence and diminishing eruptive activity brought the summit below the snowline. Erosional morphology and thick diamictons indicative of subglacial eruptions are consistent with repeated summit glaciations. Whereas Haleakala's glacial history has ended, ice caps likely will regenerate on Mauna Kea ca. 60,000 and 100,000 years in the future, after which the summit will subside below the glacial-age snowline.

Buried gullies exposed in road excavations along the margin of a loess tableland on the Loess Plateau of central China lie within a thick loess-paleosol succession that spans ≥780,000 years. Constraining ages for gully cutting and filling are provided by dates of loess and soil units cut by and capping the paleogullies. An episode of gully cutting begins at the onset of an interglaciation and ceases as the gullies begin to fill with colluvium and airborne dust during the transition to full-glacial conditions. The episodic cutting and filling of gullies implies a basic astronomical (orbital) control of gully evolution involving cyclic changes in dominant summer and winter monsoon climates, surface hydrology, and vegetation cover.

Objective: Patient-centered information management may overcome barriers that impede high-quality, safe care in the emergency department (ED). The utility of parents' report of medication data via a multimedia, touch screen interface, the asthma kiosk, was investigated. Our specific aims were (1) to estimate the validity of parents' electronically entered medication history for asthma and (2) to compare the parents' kiosk entries regarding medications to the documentation of ED physicians and nurses. Methods: We enrolled a cohort of parents to use the asthma kiosk and tested the validity of this communication channel for medication data specific to pediatric asthma. Parents' data provided via the kiosk during the ED encounter and the documentation of ED nurses and physicians were compared with a telephone-based interview with the parent after discharge that reviewed all asthma-specific medications physically present in the home. Treating clinicians in the ED were blinded to the parents' kiosk entries. Results: Sixty-six parents were enrolled and 49 of 66 (74.2%) completed the gold standard interview. When analyzed at the level of individual medications, the validity of parental report was 81% for medication name, 79% for route of delivery, 66% for the form of the medication, and 60% for dose. Parents' report improved on the validity of documentation by physicians across all medication details save for medication name. Parents' report was more valid than nursing documentation at triage for all medication details. Conclusion: Parents can provide an independent source of medication data that improves on current documentation for key variables that impact quality and safety in emergency asthma care.

The authors report on the development and evaluation of a novel patient-centered technology that promotes capture of critical information necessary to drive guideline-based care for pediatric asthma. The design of this application, the asthma kiosk, addresses five critical issues for patient-centered technology that promotes guideline-based care: (1) a front-end mechanism for patient-driven data capture, (2) neutrality regarding patients' medical expertise and technical backgrounds, (3) granular capture of medication data directly from the patient, (4) formal algorithms linking patient-level semantics and asthma guidelines, and (5) output to both patients and clinical providers regarding best practice. The formative evaluation of the asthma kiosk demonstrates its ability to capture patient-specific data during real-time care in the emergency department (ED) with a mean completion time of 11 minutes. The asthma kiosk successfully links parents' data to guideline recommendations and identifies data critical to health improvements for asthmatic children that otherwise remains undocumented during ED-based care.

Cosmogenic-nuclide exposure ages for 13 glacially transported boulders atop the Martha's Vineyard moraine, MA, USA, indicate that the southeastern margin of the Laurentide ice sheet reached its maximum extent during the last glaciation 23,200±500 yr ago. Another 10 age determinations from the younger Buzzards Bay moraine near Woods Hole, MA, indicate that this moraine complex was formed 18,800±400 yr ago. These ages correlate approximately with the terminations of cooling cycles recorded in Greenland ice cores and coeval ice-rafting events, suggesting that the marginal position of this sector of the ice sheet was tightly coupled to North Atlantic climate during the last glacial maximum.

The thick loess–paleosol succession of central China contains a detailed record of changes in East Asian monsoon climate since the late Miocene Epoch. The alternating loess–paleosol stratigraphy closely resembles the marine oxygen-isotope record, implying that episodic dust deposition and pedogenesis are in phase with global ice-volume fluctuations and controlled by variations in solar radiation reaching the land surface. Deposits equivalent to marine isotope stages (MIS) 5 through 1 have been dated by 14C, 10Be, luminescence, and magnetic susceptibility and grain-size models. Malan Loess (MIS 4–2) decreases in thickness southeastward from >30 m in the western Loess Plateau to

Magnetic susceptibility (MS) of surface sediment varies systematically across the Loess Plateau in central China, decreasing exponentially from >200×10−8 m3/kg at the northern margin of the Qinling Shan to ≤30×10−8 m3/kg near the southern margin of the Mu Us Desert. MS correlates highly with loess median grain size (r2=0.79), which decreases south-southeastward across the plateau. It also correlates with mean annual temperature (MAT) and mean annual precipitation (MAP) (r2=0.58 and 0.60, respectively), and with their product MAT×MAP (r2=0.83), which is considered a measure of potential pedogenic activity. Because regional isopleths depicting grain size and the primary meteorological parameters are nearly parallel, it is difficult to determine their relative influence on MS. A simple MS model, based on the observed spatial variation in loess thickness, permits quantitative assessment of the effect of the dust accumulation rate on the MS signal of surface sediment and isolates the likely role of climate in the production of magnetic minerals. The model suggests that 84% of the loess MS variance is dictated by the diluting effect of dust and 10–11% is associated with meteorological factors, primarily precipitation. The observed and modeled relationships support hypotheses that attribute variations in MS in the loess-paleosol succession to varying rates of dust deposition and in situ production of magnetic minerals in the accretionary soils, both of which are controlled by monsoon climate.

A periglacial ground wedge in bajada gravel near the northern base of the Qinghai Nan Shan underlies loess of late- and postglacial age. The composition and structure of the wedge fill are consistent with an ice-wedge origin, implying former permafrost and relatively moist conditions at this locality. A luminescence date of 15,100±1600 years from the wedge fill marks the end of ice-wedge activity, which is inferred to have been during the last glaciation. The present mean annual air temperature (MAAT) (−0.7 °C) is too high to produce frost cracking and ice-wedge formation, but snowline depression of ca. 700–800 m in the adjacent mountains is consistent with a reduction in MAAT of at least 3.8 °C during the last glacial maximum. Such a temperature depression would reduce MAAT to values equivalent to Arctic regions now experiencing active ice-wedge growth. The absence of loess of full-glacial age and the presence of a weakly developed palaeosol atop the bajada gravel imply a stable, cold land surface. Qinghai Lake, although reduced in size at that time, likely raised local humidity to levels that favoured ice-wedge growth in this low-altitude sector (ca. 3000–3400 m) of the Tibetan Plateau. Copyright © 2001 John Wiley & Sons, Ltd. Resume Pres de la base septentrionale de Qinghai Nan Shan, un coin periglaciaire a ete observe dans le gravier d'une bahada recouverte de loess tardi- et postglaciaire. La composition et la structure du remplissage du coin peuvent s'expliquer par le developpement d'un coin de glace, ce qui implique l'existence autrefois d'un pergelisol et de conditions relativement humides. Une date de 15.100 +/− 1600 ans a ete obtenue par luminescence pour le remplissage ; cette date marquerait la fin de l'activite du coin de glace qui serait, de ce fait, apparu pendant la derniere glaciation. De nos jours, la temperature moyenne annuelle de l'air (MAAT) est de −0.7 °C, temperature trop elevee pour produire la fissuration par le gel et la formation d'un coin de glace ; toutefois, l'abaissement de la limite des neiges eternelles d'environ 700 a 800 m dans les montagnes voisines indique une reduction de la temperature moyenne annuelle d'au moins 3.8 °C pendant le maximum de la derniere glaciation. Une telle diminution de temperature aurait reduit la temperature a une valeur semblable a celle des regions arctiques ou se developpent de nos jours des coins de glace. L'absence de loess d'âge glaciaire et la presence d'un paleosol faiblement developpe au sommet du gravier de la bahada implique que la surface est restee stable et froide. A cette epoque, le lac Qinghai, quoique reduit en taille, a probablement augmente l'humidite locale et favorise la croissance de coins de glace dans ce secteur de faible altitude (vers 3000–3400 m) du Plateau tibetain. Copyright © 2001 John Wiley & Sons, Ltd.

Five primary methods have been used to reconstruct Pleistocene snowlines or equilibrium-line altitudes (ELAs) in the tropics (23.53N}23.53S) during the last glaciation, but each has inherent errors that limit the accuracy of the results. Additional potential errorsin determiningELA depression involveestimates of modernsnowline altitude, datingresolution, topographicreconstructionof former glaciers, orographic e!ects, the presence of rockfall debris on glaciers, and calculation of regional ELA gradients. Eustatic sea-level lowering during the last glaciation is an additional factor in#uencing estimates of ELA depression (! ELA). In cases where modern snowline lies above a mountain summit, only a minimum value for ! ELA can be obtained. At 12 tropical sites in Africa, the Americas (to 103S latitude), and Paci"c islands, estimates of average ! ELA range from 440 to 1400m, but most fall in the range of 800}1000m (mean $1" "900$135m). In a regional study of ELA depression in the southern tropical Andes (8}223S), an average ! ELA of ca. 920$250m has been reported. Based on the assumption that glacier mass balance was controlled solely by ablation-season temperature, and assuming a full-glacial temperature lapse rate of !63C/km, depression of mean annual temperature in glaciated alpine areas was ca. 5.4$0.83C. If adjusted for a sea-level fall of !120m at the glacial maximum, this value is reduced to 4.7$0.83C. The "gure is based on the (unlikely) assumption that accumulation on alpine glaciers has been invariant; nevertheless,it is similar to values of temperaturedepresson (5}6.43C)for the last glaciationobtainedfrom variousterrestrial sites, but contrasts with tropical sea-surface temperature estimates that are only 1}33C cooler than present. ! 2001 Elsevier Science Ltd. All rights reserved.

Grayscale intensity profiles from photographic images offer a rapid means of obtaining paleoclimate proxy records from Chinese loess, dune sand, and paleosols. Although the data can be obtained using conventional 35-mm film images, a digital camera and laptop computer will produce a high-resolution grayscale profile at a field site within minutes. Comparison of grayscale profiles with profiles of magnetic susceptibility measured down loess and dune-sand sections at sites on the Loess Plateau and Tibetan Plateau in a range of altitudes and climatic regimes shows that the two parameters are highly correlated. Therefore, grayscale intensity is a convenient alternative to magnetic susceptibility for generating paleoclimatic data in the loess and desert-margin regions of China. The resolution of both grayscale and susceptibility profiles ultimately is limited by bioturbation, which is most pronounced in paleosols.

Holocene paleoenvironments of Harris Lake, southwestern Saskatchewan, are reconstructed from the ostracode stratigraphy of a 10.4 m sediment core. Twenty three taxa, representing nine genera, were identified and counted from 113 samples. At each depth, a theoretical faunal assemblage was derived from the raw counts. The mean and variance of chemical, climatic and physical variables were inferred from modern analogues of the fossil assemblages, using existing autecological data from 6720 sites, mostly in western Canada. These data suggest four paleoenvironments: an early-Holocene (9240–6400 years BP) variable climate supporting aspen parkland vegetation; the warm dry hypsithermal (6400–4500 years BP); a short transitional period of ameliorating climate and expanding subboreal forest (4500–3600 years BP); and the present environment since 3600 years BP. A change in regional climate with the draining of Glacial Lake Agassiz (ca. 8500 years BP) and landsliding in the watershed (ca. 4000 years BP) caused relatively rapid environmental change. The ostracode record generally corroborates the interpretations of other proxy data previously published for Harris Lake. Most of the discrepancy involves the timing and severity of maximum Holocene warmth and aridity. Peak aridity interpreted from the pollen data is earlier than in the other proxy records. Both the diatoms and ostracodes indicate highest paleosalinity between ca. 6500 and 5000 years BP, but maximum salinity in the diatom record occurs between ca. 6000–5700 years BP, whereas the ostracode-inferred salinity is relatively low at this time and peaks later at ca. 5000 years. Neither of these reconstructions suggests the short episodes of hypersalinity interpreted from the mineralogy.

Calibrated radiocarbon dates of organic matter below and above till of the last (Fraser) glaciation provide limiting ages that constrain the chronology and duration of the last advance–retreat cycle of the Puget Lobe in the central and southeastern Puget Lowland. Seven dates for wood near the top of a thick proglacial delta have a weighted mean age of 17,420 ± 90 cal yr B.P., which is the closest limiting age for arrival of the glacier near the latitude of Seattle. A time–distance curve constructed along a flowline extending south from southwestern British Columbia to the central Puget Lowland implies an average glacier advance rate of ca. 135 m/yr. The glacier terminus reached its southernmost limit ca. 16,950 yr ago and likely remained there for ca. 100 yr. In the vicinity of Seattle, where the glacier reached a maximum thickness of 1000 m, ice covered the landscape for ca. 1020 yr. Postglacial dates constraining the timing of ice retreat in the central lowland are as old as 16,420 cal yr B.P. and show that the terminus had retreated to the northern limit of the lowland within three to four centuries after the glacial maximum. The average rate of retreat was about twice the rate of advance and was enhanced by rapid calving recession along flowline sectors where the glacier front crossed deep proglacial lakes.

Loess and dune sands that mantle volcanic rocks on the northwest flank of Mauna Kea volcano consist predominantly of fine-grained pyroclasts of the alkalic Laupahoehoe Volcanics produced by explosive eruptions. The loess is divided into lower and upper units, separated by a well-developed paleosol, while older and younger dune sands are separated by loess. Four interstratified tephra marker horizons aid in regional stratigraphic correlation. Radiocarbon ages of charcoal fragments within the loess, U-series ages of rhizoliths in the dune sand, and K/Ar ages and relative stratigraphic positions of lava flows provide a stratigraphic and temporal framework. The lower loess overlies lava flows less than 103,000 ± 10,000 K/Ar yr old, and14C dates from the paleosol developed at its top average ca. 48,000 yr. Loess separating the dune sand units ranges from ca. 38,000 to 25,00014C yr old; the youngest ages from the upper loess are 17,000–18,00014C yr B.P. Dips of sand-dune foreset strata, isopachs on the upper loess, and reconstructed isopachs representing cumulative thickness of tephra associated with late-Pleistocene pyroclastic eruptions suggest that vents upslope (upwind) from the sand dunes were the primary source of the eolian sediments. Average paleowind directions during the eruptive interval (ca. 50,000–15,000 yr B.P.), inferred from cinder-cone asymmetry, distribution of tephra units, orientation of dune foreset strata, and the regional pattern of loess isopachs, suggest that Mauna Kea has remained within the trade-wind belt since before the last glaciation.

Return visits to the emergency department (ED) resulting in admission are an important marker of quality of care. Patients and families with limited English proficiency (LEP) are at risk for suboptimal care related to imprecise communication.The objective of this study was to compare the rate of return visits resulting in admission in LEP patients to the rate in the English-speaking patients.We assembled a retrospective cohort of patients cared for in a pediatric, tertiary ED. Eligible patients included those who were discharged on the first encounter, and those who returned and were admitted to the hospital within 72 hours of ED discharge were identified. A logistic regression was performed comparing the rate of return visits resulting in admission in the LEP and non-LEP populations adjusting for emergency severity index and time of day at ED visit.A total of 119,782 patients were discharged from the ED during a 32-month study period. Of these patients, 11.7% (14,053) identified a language other than English as their primary language. The rate of return visits resulting in admission was 1.2% (1279/105,729) among English speakers and 1.6% (220/14,053) in the LEP population. Patients with LEP were more likely to return to the ED for admission (odds ratio, 1.30; 95% confidence interval, 1.12-1.50; P0.001) The increased risk of a return visit for LEP patients remained significant after controlling for age, emergency severity index, and time of day (adjusted odds ratio, 1.43; 95% confidence interval, 1.23-1.66; P0.001).Patients with LEP are at higher risk of return visit for admission.

High-resolution paleomonsoon proxy records from peat and eolian sand–paleosol sequences at the desert–loess transition zone in China denote a rapid oscillation from cold–dry conditions (11,200–10,600 14C yr B.P.) to cool–humid conditions (10,600–10,200 14C yr B.P.), followed by a return to cold–dry climate (10,200–10,000 14C yr B.P.). Variations in precipitation proxies suggest that significant climatic variability occurred in monsoonal eastern Asia during the Younger Dryas interval. Late-glacial climate in the Chinese desert–loess belt that lies downwind from Europe was strongly influenced by cold air from high latitudes and from the North Atlantic via the westerlies. The inferred precipitation variations were likely caused by variations in the strength of the Siberian high, which influenced the pressure gradient between land and ocean and therefore influenced the position of the East Asian monsoon front.

A poly(tetramethylene oxide) [PTMO] based polyetherurethaneurea (PEUU), produced by Polymer Technology Group Inc. (Emeryville, CA) as a Primary Reference Material, was spin-cast from a 3% (w/v) DMAc solution onto a glass cover slip. The polymer coating was analyzed at ambient temperature by XPS using a 55° take-off angle. An elemental survey scan shows the presence of C, N, and O (no trace elements were detected). The C 1s spectrum shows a nearly equal concentration of ether and hydrocarbon environments, suggesting that surface localization of the PTMO soft segment is occuring. A broadened peak at higher binding energy (∼289.1 eV) is indicative of the presence of both urea and urethane nitrogens. The N 1s peak location suggests that there is a greater contribution from urea groups. The dominant contributors to the O 1s spectra are ether functionalities. The urea and urethane contributions are apparent as high and low binding energy tails but are too small to be resolved accurately.

EPISODES of massive iceberg release (Heinrich events)1-3 into the North Atlantic Ocean during the last glaciation were associated with recurring episodes of unusually cold North Atlantic surface water (Bond cycles)4 and cold air temperatures over Greenland (Dansgaard-Oeschger events)5,6. Four of the youngest of these cold events have also been reported in climate records from sites outside the North Atlantic region7, but until now the entire suite has been identified only in North Atlantic marine sediments, Greenland ice-core records and, tentatively, in French lake sediments8. Here we examine grain-size data from Chinese loess and intercalated accretionary palaeosols of last-glacial age for evidence of similar climate signals remote from the North Atlantic region. We see grain-size maxima with ages that match those of the last six Heinrich events, which we interpret as an indication of the changing strength of the East Asian winter monsoon, which largely controls the transport and deposition of central Asian aeolian dust. Thus it seems that these Heinrich events have left their signature in the Chinese loess record. This is consistent with simulations of the glacial climate9, which imply that the climates of the North Atlantic and China were linked by the effect of westerly winds.

The Chinese loess-paleosol sequence constitutes an important record of variations in Asian monsoon climate over the past 2.4 myr. Magnetic susceptibility of loess and paleosols has been used as a proxy for summer monsoon intensity, while median grain size has been regarded as a measure of the strength of winter monsoon winds that were responsible for most of the dust transport. However, median grain size is only an approximate index of winter monsoon strength because both paleosols and loess have been modified, to various degrees, by weathering processes that have produced pedogenic clay. The quartz component of loess and paleosols is largely unaffected by weathering processes and therefore constitutes a more reliable proxy index of monsoon wind strength. Median grain size (Qmd) and maximum grain size (Qmax) values of monomineralic quartz isolated from the loess-paleosol section at Luochuan in the central Loess Plateau are characterized by two main intervals during the last ca. 130,000 yr when these parameters were significantly greater than 9 and 85 μm, respectively, and three main intervals when they were lower. The data imply that the winter monsoon weakened during the intervals with low Qmd and Qmax values, which coincide with marine oxygen isotope stages 5, 3, and 1, and was strongest ca. 67,000 and 20,000 yr ago during isotope stages 4 and 2. However, both quartz grainsize records display second-order high-frequency, high-amplitude variations, which are lacking in the magnetic susceptibility record, that imply rapid and significant changes in atmospheric conditions that affect dust transport and deposition.

Objectives/Hypothesis Penetrating palatal trauma in children presents a diagnostic dilemma regarding the small but severe risk of injury to carotid vessels. Decisions regarding which children require computed tomography with angiography must be balanced against the risk of radiation-induced malignancy. Our objectives were to compare outcomes between children with and without computed tomography with angiography in the evaluation of palatal trauma and to identify thresholds where the ideal strategy changes in the management of children with palatal trauma through sensitivity analyses. Study Design Decision analytic techniques were used to compare management strategies for penetrating palatal trauma. Methods We assigned utilities to the following outcomes: 1) perfect health, 2) future malignancy, 3) carotid injury diagnosed by computed tomography with angiography, and 4) delayed diagnosis of stroke. We calculated outcomes when the risk of stroke ranged from 0.01% to 5.0% for a hypothetical cohort of 10,000 injured children. Results Not obtaining computed tomography with angiography is the optimal strategy when the stroke risk is less than 4.5%. In two-way sensitivity analyses that consider a range of probabilities of radiation-induced malignancy and stroke, not obtaining computed tomography with angiography on all patients dominates as a strategy until the risk of stroke exceeds 2.3%, and the risk of malignancy is under 0.24%. Routine imaging would introduce 20 additional malignancies for each additional stroke diagnosed. Conclusions Routine use of computed tomography with angiography for well-appearing children with palatal trauma should be reconsidered, as the risk of radiation-induced malignancy may outweigh the benefit of identifying the rare carotid injury. Level of Evidence 2b.

The extent of Pleistocene glaciers is based on valley morphology and end moraines interpreted from LANDSAT images. In the absence of radiometric age control, mapped glaciers are assumed to date to the last glaciation. Fourteen glaciers were ≥ 50 km long. The full-glacial equilibrium line altitude likely lay about 900–1000 m below the estimated modern snowline.

Glacial deposits atop Mauna Kea volcano record three Pleistocene glaciations. The youngest ice cap covered 70 km 2 , averaged about 75 m thick, and extended as low as 3200 m. K/Ar, 36 Cl, OSL, and 14 C dating points to an MIS 2 age for the youngest drift, and MIS 4 and 6 for the two older ones.

Deposits of large Pleistocene valley glaciers in the Olympic Mountains and Cascade Range are separated by deposits of the Puget Lobe of the Cordilleran Ice Sheet. The alpine deposits, of Late to Middle Pleistocene age, are not yet closely dated. Dates from the ice-sheet sediments place the last glacial maximum at about 17,000 14C yr ago.

The Baxie loess section, just east of the Tibetan Plateau, contains evidence showing that the Asian monsoon climate experienced an abrupt reversal near the end of the last glacial age. Rapid deposition of dust under cool, dry full-glacial conditions gave way to an interval of soil development and reduced dust influx attributed to a strengthening of the warm, moist summer monsoon. A subsequent abrupt increase in dust deposition, a response to a weakening of the summer monsoon, was later followed by renewed soil formation as summer monsoon circulation again intensified during the early Holocene. By one interpretation, the thin upper loess is a manifestation of the European Younger Dryas oscillation; however, in this case the available 14C ages require either that (1) onset of loess deposition lagged the beginning of the Younger Dryas event in Europe by as much as 2000 calibrated 14C years or (2) all the 14C ages are too young, possibly due to contamination. Alternatively, the late-glacial paleosol, the top of which is synchronous with the abrupt end of the late-glacial δ18O anomaly in the Dye 3 Greenland ice core, records the Younger Dryas event. Such an interpretation is consistent with general circulation model simulations of Younger Dryas climate that show strong seasonality and a strengthened summer monsoon, and with marine cores from the western Pacific Ocean that contain evidence of pronounced cooling of surface waters during Younger Dryas time.

BackgroundThe development of health information technologies should be informed by iterative experiments in which qualitative and quantitative methodologies provide a deeper understanding of the abilities, needs, and goals of the target audience for a personal health application. ObjectiveOur objective was to create an interface for parents of children with attention-deficit hyperactivity/disorder (ADHD) to enter disease-specific information to facilitate data entry with minimal task burden. MethodsWe developed an ADHD-specific personal health application to support data entry into a personally controlled health record (PCHR) using a three-step, iterative process: (1) a needs analysis by conducting focus groups with parents of children with ADHD and an heuristic evaluation of a prerelease version of a PCHR, (2) usability testing of an initial prototype personal health application following a “think aloud” protocol, (3) performance testing of a revised prototype, and (4) finalizing the design and functionality of the ADHD personal health application. Study populations for the three studies (focus groups and two usability testing studies) were recruited from organizations in the greater Boston area. Study eligibility included being an English- or Spanish-speaking parent who was the primary caretaker of a school-age child with ADHD. We determined subjects’ health literacy using the Test of Functional Health Literacy in Adults (TOFHLA). We assessed subjects’ task burden using the National Aeronautics and Space Administration (NASA) Task Load Index. To assess the impact of factors associated with the time spent entering data, we calculated Pearson correlation coefficients (r) between time on task and both task burden and subject characteristics. We conducted t tests to determine if time on task was associated with successful task completion. ResultsThe focus groups included three cohorts: 4 Spanish-speaking parents with diverse health literacy, 4 English-speaking parents with lower health literacy, and 7 English-speaking parents with higher health literacy. Both the initial usability testing cohort (n = 10) and the performance-testing cohort (n = 7) included parents of diverse health literacy and ethnicity. In performance testing, the prototype PCHRs captured patient-specific data with a mean time on task of 11.9 minutes (SD 6.5). Task burden experienced during data entry was not associated with successful task completion (P = .92). Subjects’ past computer experience was highly correlated with time on task (r = .86, P = .01), but not with task burden (r = .18, P = .69). The ADHD personal health application was finalized in response to these results by (1) simplifying the visual environment, (2) including items to support users limited by health literacy or technology experience, and (3) populating the application’s welcome screen with pictures of culturally diverse families to establish a personal family-oriented look and feel. ConclusionsOur patient-centered design process produced a usable ADHD-specific personal health application that minimizes the burden of data entry.

Objective The authors examined the validity of documentation produced during paediatric emergency care to determine if a patient-driven health information technology called ParentLink produced higher-quality data than documentation completed by nurses and physicians. Design The authors analysed the quality of information across elements of allergies to medications and the history of present illness (HPI) collected during a quasiexperimental intervention study where control periods with usual care alternated with intervention periods when ParentLink was operational. Documentation by emergency department (ED) providers was abstracted and compared with information generated through ParentLink. The criterion standard for the history of allergies to medications was a structured telephone interview with parents after the ED visit. A valid report for a medication allergy was one that was both accurate and complete. Completeness of the HPI for acute head trauma was evaluated across seven elements relevant to an evidence-based risk assessment. Results Of 1410 enrolled parents, 1111/1410 (79%) completed the criterion standard interview. Parents’ valid reports of allergies to medications were higher than those of nurses (parents 94%, nurses 88%, p

Pleistocene alluvial terraces of the nonglaciated Ba River drainage basin on the north flank of the Qinling Shan are capped by a succession of loess units and paleosols that correlate with the standard marine isotope chronology and are used to date the subjacent alluvial gravels. Alluvial fills were deposited during isotope stages 2, 6, 8, 12, and 16, whereas terracing occurred during interglacial stages 1, 5, 7, 11, and 15. The apparent absence of terraces dating to stage 14 and stage 4 may be due to the lesser intensity of these glaciations compared to that of stage 2, although disruption of the alluvial regime by local tectonism is a likely alternative for the lack of a stage 4 terrace. A stage 10 terrace was not positively identified from available exposures; its possible absence could be related to post-stage 12 uplift. Aggradational episodes correlate with glaciations and loess deposition, whereas degradational episodes correlate with interglaciations or interstades and soil formation, implying that climate is the primary control on Quaternary paleohydrology. This in turn points to variations in the Earth's orbital geometry as the major factor that modulates both climate and, ultimately, the fluvial system in the Qinling Shan. In this region, glaciations were dominated by a cold, dry winter monsoon climate, whereas during interstades and interglaciations a warmer and wetter climate prevailed, implying strengthening of the summer monsoon. Both the loess/paleosol and the alluvial records are consistent with climate-model simulations spanning the last 18,000 yr that show a change from cold, dry conditions during the last glacial maximum to a climate warmer and wetter than present during the first half of the Holocene.