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The Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2) updates NASA's previous satellite era (1980 - onward) reanalysis system to include additional observations and improvements to the Goddard Earth Observing System, Version 5 (GEOS-5) Earth system model. As a major step towards a full Integrated Earth Systems Analysis (IESA), in addition to meteorological observations, MERRA-2 now includes assimilation of aerosol optical depth (AOD) from various ground- and space-based remote sensing platforms. Here, in the first of a pair of studies, we document the MERRA-2 aerosol assimilation, including a description of the prognostic model (GEOS-5 coupled to the GOCART aerosol module), aerosol emissions, and the quality control of ingested observations. We provide initial validation and evaluation of the analyzed AOD fields using independent observations from ground, aircraft, and shipborne instruments. We demonstrate the positive impact of the AOD assimilation on simulated aerosols by comparing MERRA-2 aerosol fields to an identical control simulation that does not include AOD assimilation. Having shown the AOD evaluation, we take a first look at aerosol-climate interactions by examining the shortwave, clear-sky aerosol direct radiative effect. In our companion paper, we evaluate and validate available MERRA-2 aerosol properties not directly impacted by the AOD assimilation (e.g. aerosol vertical distribution and absorption). Importantly, while highlighting the skill of the MERRA-2 aerosol assimilation products, both studies point out caveats that must be considered when using this new reanalysis product for future studies of aerosols and their interactions with weather and climate.

Semiconductor nanowires (NWs) have been demonstrated as a potential platform for a wide-range of technologies, yet a method to interconnect functionally encoded NWs has remained a challenge. Here, we report a simple capillarity-driven and self-limited welding process that forms mechanically robust and Ohmic inter-NW connections. The process occurs at the point-of-contact between two NWs at temperatures 400-600 °C below the bulk melting point of the semiconductor. It can be explained by capillarity-driven surface diffusion, inducing a localized geometrical rearrangement that reduces spatial curvature. The resulting weld comprises two fused NWs separated by a single, Ohmic grain boundary. We expect the welding mechanism to be generic for all types of NWs and to enable the development of complex interconnected networks for neuromorphic computation, battery and solar cell electrodes, and bioelectronic scaffolds.

Introduction: On 21 August 2011 an F3 tornado hit the Canadian town of Goderich, Ontario, leaving 40 people injured and one dead. Specific medium-term changes in utilization of health care following a disaster have not been analyzed in medical literature. Documenting the emergency department utilization through this subacute period would be helpful to enable institutions and healthcare practitioners to be better prepared for future events., Methods: A medical chart review was conducted at the Alexandra Marine and General Hospital in Goderich. All emergency department visits made during the 30 days after the Tornado in 2011 (intervention group), 30 days prior to the tornado in 2011 (primary control group), and during the similar calendar period of 30 days after the tornado in 2010 (seasonal control group) were reviewed. Medical diagnoses of all patients who presented at the emergency department were collected and compared., Results: Fewer people presented to the emergency department following the tornado than during the control periods, and those who did were significantly older than those who presented in the control periods ( p <0.001). A significantly greater number of patients presented with undiagnosed medical problems, many came to refill their medications, and significantly fewer people left the emergency department without being seen ( p <0.001)., Conclusions: This study identifies the medical conditions that are most likely to be seen in an emergency department following a tornado in a rural Ontario community. This information serves to inform the medical community and other hospitals how to increase their level of preparedness should a comparable disaster occur again in the future.

For nanomaterials, surface chemistry can dictate fundamental material properties, including charge-carrier lifetimes, doping levels, and electrical mobilities. In devices, surface defects are usually the key limiting factor for performance, particularly in solar-energy applications. Here, we develop a strategy to uniformly and selectively passivate defect sites in semiconductor nanomaterials using a vapor-phase process termed targeted atomic deposition (TAD). Because defects often consist of atomic vacancies and dangling bonds with heightened reactivity, we observe-for the widely used p-type cathode nickel oxide-that a volatile precursor such as trimethylaluminum can undergo a kinetically limited selective reaction with these sites. The TAD process eliminates all measurable defects in NiO, leading to a nearly 3-fold improvement in the performance of dye-sensitized solar cells. Our results suggest that TAD could be implemented with a range of vapor-phase precursors and be developed into a general strategy to passivate defects in zero-, one-, and two-dimensional nanomaterials.

The effectiveness of chemical amendment of pig slurry to ameliorate phosphorus (P) losses in runoff is well studied, but research mainly has concentrated only on the runoff pathway. The aims of this study were to investigate changes to leachate nutrient losses, soil properties and greenhouse gas (GHG) emissions due to the chemical amendment of pig slurry spread at 19 kg total phosphorus (TP), 90 kg total nitrogen (TN), and 180 kg total carbon (TC) ha(-1). The amendments examined were: (1) commercial grade liquid alum (8% Al2O3) applied at a rate of 0.88:1 [Al:TP], (2) commercial-grade liquid ferric chloride (38% FeCl3) applied at a rate of 0.89:1 [Fe:TP] and (3) commercial-grade liquid poly-aluminium chloride (PAC) (10% Al2O3) applied at a rate of 0.72:1 [Al:TP]. Columns filled with sieved soil were incubated for 8 mo at 10 °C and were leached with 160 mL (19 mm) distilled water wk(-1). All amendments reduced the Morgan's phosphorus and water extractable P content of the soil to that of the soil-only treatment, indicating that they have the ability to reduce P loss in leachate following slurry application. There were no significant differences between treatments for nitrogen (N) or carbon (C) in leachate or soil, indicating no deleterious impact on reactive N emissions or soil C cycling. Chemical amendment posed no significant change to GHG emissions from pig slurry, and in the cases of alum and PAC, reduced cumulative N2O and CO2 losses. Chemical amendment of land applied pig slurry can reduce P in runoff without any negative impact on nutrient leaching and GHG emissions. Future work must be conducted to ascertain if more significant reductions in GHG emissions are possible with chemical amendments., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Losses of phosphorus (P) from soil and slurry during episodic rainfall events can contribute to eutrophication of surface water. However, chemical amendments have the potential to decrease P and suspended solids (SS) losses from land application of slurry. Current legislation attempts to avoid losses to a water body by prohibiting slurry spreading when heavy rainfall is forecast within 48 h. Therefore, in some climatic regions, slurry spreading opportunities may be limited. The current study examined the impact of three time intervals (TIs; 12, 24 and 48 h) between pig slurry application and simulated rainfall with an intensity of 11.0 ± 0.59 mm h(-1). Intact grassed soil samples, 1 m long, 0.225 m wide and 0.05 m deep, were placed in runoff boxes and pig slurry or amended pig slurry was applied to the soil surface. The amendments examined were: (1) commercial-grade liquid alum (8 % Al2O3) applied at a rate of 0.88:1 [Al/ total phosphorus (TP)], (2) commercial-grade liquid ferric chloride (38 % FeCl3) applied at a rate of 0.89:1 [Fe/TP] and (3) commercial-grade liquid poly-aluminium chloride (10 % Al2O3) applied at a rate of 0.72:1 [Al/TP]. Results showed that an increased TI between slurry application and rainfall led to decreased P and SS losses in runoff, confirming that the prohibition of land-spreading slurry if heavy rain is forecast in the next 48 h is justified. Averaged over the three TIs, the addition of amendment reduced all types of P losses to concentrations significantly different (p < 0.05) to those from unamended slurry, with no significant difference between treatments. Losses from amended slurry with a TI of 12 h were less than from unamended slurry with a TI of 48 h, indicating that chemical amendment of slurry may be more effective at ameliorating P loss in runoff than current TI-based legislation. Due to the high cost of amendments, their incorporation into existing management practices can only be justified on a targeted basis where inherent soil characteristics deem their usage suitable to receive amended slurry.

The silicon p-n junction is the most successful solar energy technology to date, yet it accounts for a marginal percentage of worldwide energy production. To change the status quo, a disruptive technological breakthrough is needed. In this Perspective, we discuss the potential for complex silicon nanowires to serve as a platform for next-generation photovoltaic devices. We review the synthesis, electrical characteristics, and optical properties of core/shell silicon nanowires that are subwavelength in diameter and contain radial p-n junctions. We highlight the unique features of these nanowires, such as optical antenna effects that concentrate light and intense built-in electric fields that enable ultrafast charge-carrier separation. We advocate a paradigm in which nanowires are arranged in periodic horizontal arrays to form ultrathin devices. Unlike conventional planar silicon, nanowire structures provide the flexibility to incorporate multiple semiconductor, dielectric, and metallic materials in a single system, providing the foundation for a disruptive, unconventional solar energy technology.

Semiconductor nanowires (NWs) are a developing platform for electronic and photonic technologies, and many demonstrated devices utilize a p-type/n-type (p-n) junction encoded along either the axial or radial directions of the wires. These miniaturized junctions enable a diverse range of functions, from sensors to solar cells, yet the physics of the devices has not been thoroughly evaluated. Here, we present finite-element modeling of axial and radial Si NW p-n junctions with total diameters of ~240 nm and donor/acceptor doping levels ranging from 10(16) to 10(20) cm(-3). We evaluate the photovoltaic performance of horizontally oriented NWs under 1 sun illumination and compare simulated current-voltage data to experimental measurements, permitting detailed analysis of NW performance, limitations, and prospect as a technology for solar energy conversion. Although high surface-to-volume ratios are cited as detrimental to NW performance, radial p-n junctions are surprisingly insensitive to surface recombination, with devices supporting open-circuit voltages (V(OC)) of ~0.54 V and internal quantum efficiencies of 95% even with high surface recombination velocities (SRVs) of 10(5) cm/s. Axial devices, in which the depletion region is exposed to the surface, are far more sensitive to SRV, requiring substantially lower values of 10(3)-10(4) cm/s to produce the same level of performance. For low values of the SRV (<100 cm/s), both axial and radial NWs can support V(OC) values of >0.70 V if the bulk minority carrier lifetime is 1 μs or greater. Experimental measurements on NWs grown by a vapor-liquid-solid mechanism yield V(OC) of 0.23 and 0.44 V for axial and radial NWs, respectively, and show that axial devices are limited by a SRV of ~7 × 10(3) cm/s while radial devices are limited by a bulk lifetime of ~3 ns. The simulations show that with further development the electrical characteristics of 200-300 nm Si NWs are sufficient to support power-conversion efficiencies of 15-25%. The analysis presented here can be generalized to other semiconductor homo- and heterojunctions, and we expect that insights from finite element modeling will serve as a powerful method to guide the design of advanced nanoscale structures.

Introduction: The Canadian Association of Emergency Physicians (CAEP) published a position statement in 2006 encouraging immediate access to emergency medicine ultrasonography (EMUS) 24 hours a day, 7 days a week. However, barriers to advanced imaging care still exist in many rural hospitals. Our study investigated the current availability of EMUS in rural communities and physicians' ability to use this technology., Methods: A literature review and interviews with rural physicians were conducted in the summer of 2010 to design a questionnaire focusing on EMUS. The survey was then sent electronically or via regular mail in November 2010 to all Ontario physicians self-identified as "rural." Descriptive statistics and the Fisher exact test were used to analyze the data., Results: A total of 207 rural physicians responded to the survey (response rate 28.6%). Of the respondents, 70.9% were male, median age was 49 years and median year of graduation was 1988. The respondents had been in practice for a median of 20 years and had been in their present community for a median of 15 years. More than two-thirds of physicians (69.5%) practised in communities with populations of less than 10 000. Nearly three-quarters (72.6%) worked in a rural emergency department (ED). Almost all (96.9%) reported having access to ultrasonography in the hospital. However, only 60.6% had access to ultrasonography in the ED. Less than half (44.4%) knew how to perform ultrasonography, with 77.3% citing lack of training. Of those using EMUS, 32.5% were using it at least once per shift. The most common reason to use EMUS was to rule out abdominal aortic aneurysm (58.3%). Most respondents (71.5%) agreed or strongly agreed that EMUS is a skill that all rural ED physicians should have., Conclusion: Patients in many rural EDs do not have immediate access to EMUS, as advocated by CAEP. This gap in care needs to be addressed to ensure that all patients, no matter where they live, have access to this proven imaging modality.

In Ireland, no database detailing the design, influent loading rates or performance of constructed wetlands (CWs) exists. On account of this, they are designed without any protocol based on empirical data. The aim of this paper was to provide the first published data on the performance of free-water surface flow (FWSF) CWs treating primary and secondary-treated municipal wastewater, and agricultural dairy soiled water (DSW) in Ireland. In total, the performance of thirty-four FWSF CWs, comprising fourteen CWs treating primary-treated municipal wastewater, thirteen CWs treating secondary-treated municipal wastewater, and seven CWs treating DSW, were examined. In most CWs, good organic, suspended solids (SS) and nutrient removal was measured. At an average organic loading rate (OLR) of 10 and 9 g biochemical oxygen demand (BOD) m(-2) d(-1), CWs treating primary and secondary wastewater removed 95 and 84% of influent BOD. Constructed wetlands treating DSW had an average BOD removal of 98%. At average SS loading rates of 6 and 14 g m(-2) d(-1), CWs treating primary and secondary wastewater had a 96 and an 82% reduction, and produced a final effluent with a concentration of 14 and 13 mg L(-1). Constructed wetlands treating DSW produced a final effluent of 34 mg L(-1) (94% reduction). Similar to other studies, all CWs examined had variable performance in ammonium-N (NH(4)(+)-N) removal, with average removals varying between 37% (for CWs treating secondary wastewater) and 88% (for CWs treating DSW). Variable ortho-phosphorus (PO(4)(3-)-P) removal was attributable to different durations of operation, media types and loading rates., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The analysis of temporal and spatial patterns of gene expression is critically important for many kinds of developmental studies, including the construction of gene regulatory networks. Recently, multiplex, fluorescent, whole mount in situ hybridization (multiplex F-WMISH), applied in combination with confocal microscopy, has emerged as the method of choice for high-resolution, three-dimensional (3D) mapping of gene expression patterns in developing tissues. We have developed an image analysis tool, GeneExpressMap (GEM), that facilitates the rapid, 3D analysis of multiplex F-WMISH data at single-cell resolution. GEM assigns F-WMISH signal to individual cells based upon the proximity of cytoplasmic hybridization signal to cell nuclei. Here, we describe the features of GEM and, as a test of its utility, we use GEM to analyze patterns of regulatory gene expression in the non-skeletogenic mesoderm of the early sea urchin embryo. GEM greatly extends the power of multiplex F-WMISH for analyzing patterns of gene expression and is a valuable tool for gene network analysis and many other kinds of developmental studies., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Many computational chemistry analyses require the generation of conformers, either on-the-fly, or in advance. We present Confab, an open source command-line application for the systematic generation of low-energy conformers according to a diversity criterion., Results: Confab generates conformations using the 'torsion driving approach' which involves iterating systematically through a set of allowed torsion angles for each rotatable bond. Energy is assessed using the MMFF94 forcefield. Diversity is measured using the heavy-atom root-mean-square deviation (RMSD) relative to conformers already stored. We investigated the recovery of crystal structures for a dataset of 1000 ligands from the Protein Data Bank with fewer than 1 million conformations. Confab can recover 97% of the molecules to within 1.5 Å at a diversity level of 1.5 Å and an energy cutoff of 50 kcal/mol., Conclusions: Confab is available from http://confab.googlecode.com.

Aims: To determine the value of routine follow-up in detecting and salvaging recurrence after radical treatment of locally advanced head and neck squamous cell carcinoma and to identify clinical or pathological prognostic factors that predicted for survival., Materials and Methods: A retrospective medical chart review was conducted at the Odette Cancer Centre between January 2000 and May 2006. Two hundred and twenty-three patients with advanced (stage III or IV) squamous cell carcinoma of the head and neck who were treated with curative intent were reviewed. Recurrences were divided into local, regional or distant recurrences. The detection method for each recurrence was categorised as self or physician detected. A self-detected recurrence arose from symptoms that led to investigations that confirmed a recurrence (even if initiated at the time of a routine visit), whereas a physician-detected recurrence was found during the routine follow-up examination and was asymptomatic., Results: There was no evidence to suggest a significant improvement in disease-free or overall survival in the physician-detected versus patient-detected groups. Regional and distant recurrences were only detected by physicians in one-fifth of cases and, overall, patients self-detected their own recurrence in two-thirds of the cases that experienced disease progression within the sample. Of the 12 clinical/pathological variables considered, only the response to treatment and perineural invasion were associated with survival., Conclusions: Current surveillance methods do not appear to improve cancer control in the stage III/IV head and neck squamous cell carcinoma population. However, technological advances and biomarker development may lead to surveillance technique enhancements. Also, post-treatment follow-up remains important for the evaluation of treatment results, emotional support and management of late complications. Among the clinical and pathological factors considered, only the treatment response and perineural invasion predicted survival., (Copyright © 2010 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Excellent enantiocontrol (up to 98% ee) is achieved in copper catalyzed C-H insertions of alpha-diazosulfones to form thiopyrans, with up to 60% ee in C-H insertions leading to sulfolanes.

This paper reports two cases of acrometastasis to the hands. The first case involved a 78-year-old woman with a permeative osteolytic lesion in her proximal second metacarpal. A biopsy of this lesion suggested a diagnosis of non-small-cell lung carcinoma with secondary osseous metastasis. This was the first presentation of the woman's primary diagnosis. A single 8-Gy fraction of palliative radiotherapy was delivered to the patient's left hand. The treatment proved successful: the woman soon experienced pain relief and regained the use of her hand. The second case involved a 69-year-old woman with extensive lytic destruction involving the proximal two thirds of her third metacarpal. This patient had been diagnosed with carcinoma of the breast in 1990. She also received a single 8-Gy fraction of radiation, which improved both her pain and her hand mobility.An extensive review of the literature uncovered 257 previously reported cases of acrometastasis. Articles were analyzed based on age and sex of the patient, site of the primary carcinoma, metastatic locations within the hand and affected appendage or appendages, the treatment given, and the patient's length of survival. Men were almost twice as likely to experience acrometastasis as women, and the median age of the patients overall was 58 years (range: 18 months-91 years). Lung, kidney, and breast carcinoma were the three most prevalent primary diagnoses reported in the literature. Cancers of the colon, stomach, liver, prostate, and rectum affected the remainder of the population.Overall, the right hand was more often host to the metastatic lesions. In addition, almost 10% of the patients experienced lesions in both hands. The third finger was the digit most affected by osseous metastases reported in the literature. Lesions of the thumb, fourth finger, second finger, and fifth finger were less commonly reported. The region of the digit most often affected within the patient population was the distal phalanx. The metacarpal bones, proximal phalanges, and middle phalanges comprised the remainder of the four most frequent acrometastatic sites. In the literature, single lesions were more prevalent than multiple bony lesions.Based on the reported cases, amputation appeared to be the preferred method of treatment. Radiation, excision, and systemic therapy were the next most frequently used treatments. Patient survival was not well documented within the literature. However, the median survival of patients in the reported cases was 6 months. Thus, our review suggested that a diagnosis of hand metastasis is an indication of poor prognosis.This report serves to emphasize the importance of properly diagnosing acrometastases. Identifying and effectively treating these metastases in a timely manner can lead to a dramatic improvement in a patient's quality of life.

Shadow-band radiometers in general, and especially the Multi-Filter Rotating Shadow-band Radiometer (MFRSR), are widely used for atmospheric optical depth measurements. The major programs running MFRSR networks in the United States include the Department of Energy Atmospheric Radiation Measurement (ARM) Program, U.S. Department of Agriculture UV-B Monitoring and Research Program, National Oceanic and Atmospheric Administration Surface Radiation (SURFRAD) Network, and NASA Solar Irradiance Research Network (SIRN). We discuss a number of technical issues specific to shadow-band radiometers and their impact on the optical depth measurements. These problems include instrument tilt and misalignment, as well as some data processing artifacts. Techniques for data evaluation and automatic detection of some of these problems are described.

Polarization-sensitive detection of elastic backscattered light is useful for detection of cloud phase and depolarizing aerosols. The U.S. Department of Energy's Atmospheric Radiation Measurement Program has deployed micropulse lidar (MPL) for over a decade, but without polarized detection. Adding an actively-controlled liquid crystal retarder provides the capability to identify depolarizing particles by alternately transmitting linearly and circularly polarized light. This represents a departure from established techniques, which transmit exclusively linear polarization or exclusively circular polarization. Mueller matrix calculations yield simple relationships between the well-known linear depolarization ratio delta(linear), the circular depolarization ratio delta(circ), and this MPL depolarization ratio delta(MPL).

Rationale: An association between tardive dyskinesia (TD) and severely impaired metabolism of the large neutral amino acid (LNAA), phenylalanine (Phe) was defined in a group of mentally retarded patients. Subsequently, an altered kinetics of Phe was associated with TD in men with schizophrenia based on plasma analyses subsequent to the ingestion of a protein meal., Methods: In the present study, a standardized oral challenge of pure Phe (100 mg/kg in 170 ml orange juice) was administered to psychiatric patients of both sexes (n = 312), with and without TD after an overnight fast. Plasma LNAA levels were assayed both fasting and 2 h subsequent to the ingestion of the challenge. The extent of the increase in plasma Phe levels 2 h following a standardized challenge is determined by the sum of the kinetic processes of plasma absorption, tissue distribution, metabolism and elimination., Results: The study hypothesis, that TD would be associated with significantly higher post-challenge plasma Phe indices of an absolute plasma Phe level and plasma Phe/LNAA ratio (a brain availability measure), was verified for the study men (n = 209), but not for the study women (n = 103)., Conclusions: The demonstrated altered kinetics of Phe in men with TD indicates a greater availability of Phe to the brain in these men. We suggest that the disorder may be related to the effects of this greater availability. Such effects could be the direct neurotoxic effects of Phe and its metabolites and/or the modulating effects of these compounds on the synthesis of the monoamine neurotransmitters. The fact that TD (Yes/No) group differences in post-challenge plasma Phe indices were not seen for the study women suggests the possibility of a sex difference in the biology of TD that we propose may be reflective of the young age of the study sample.

Rationale: Prior studies had suggested (a) that a lessened ability to clear ingested forms of the large neutral amino acid (LNAA), phenylalanine (Phe), was associated with having tardive dyskinesia (TD), and (b) that greater availability of a group of LNAA, the branched chain amino acids (BCAA), concomitant with the lower availability of Phe to the brain are associated with a decrease in TD symptoms. The present study was then conducted to test whether increasing the daily intake of the BCAA would decrease the symptoms of TD., Methods: A 2-week trial of a BCAA medical food administered three times a day was conducted in nine men with long neuroleptic treatment histories. Frequency counts of TD movements were collected by videotape throughout the trial and these tapes were analyzed in blind random sequence for both patient and time for TD symptom level changes subsequent to completion of the trial. Plasma levels of the LNAA were also collected throughout the trial., Results: A statistically significant decrease in the level of TD symptoms was observed for the sample. The symptom changes were also clinically significant in that six of the nine subjects had symptom decreases of at least 58%, with all subjects having a decrease of at least 38%. BCAA administration increased plasma BCAA concentrations and BCAA/LNAA ratios and decreased plasma Phe concentrations and the Phe/LNAA ratio. Analyses indicated a strong significant correlation between the percent increase in the plasma BCAA values at the first administration and the percent improvement in TD over the trial in eight of the nine subjects., Conclusions: The BCAA show promise as a treatment for TD. The decrease in TD symptoms seen in the trial may have been modulated by the BCAA treatment-induced increased availability of the BCAA and decreased availability of Phe to the brain.

Study Objective: To quantify the number of individuals bitten, the number of bites per patient, and the types of injuries and complications caused by law enforcement K-9 dog bites treated in the Jail Ward Emergency Department of the Los Angeles County-University of Southern California Medical Center. These variables were compared before and after a change in K-9 police policy from the "bite-and-hold" to the "find-and-bark" technique or stricter controls were instituted over the K-9 teams., Methods: A retrospective chart review of all patients in police custody with K-9 dog bites who presented to the Jail Ward ED between January 1, 1988, and December 31, 1995, was conducted. Demographic data of patients with K-9 dog bites, the number and location of bites, complications, procedures performed, and management of bites were recorded and compared between the periods 1988-1991 (before the policy changes) and 1992-1995 (after the changes)., Results: Between 1988 and 1995 790 in-custody patients were treated for K-9 dog bites in the Jail Ward ED; 705 charts were available for review. Nearly all the patients (98.6%) were male, with a mean age of 25; 85.0% were Hispanic or black. More than half (57.2%) sustained three or more bites, mainly to the extremities. Complications ensued in 19.3%: vascular in 7.0%, infection in 5.0%, fracture or cortical violation in 4.0%, nerve injury in 1.9%, and tendon injury in 1.1%. Half (49.9%) were hospitalized, with a median stay of 3 days. After the change in K-9 policy, the number of patients with K-9 dogs bites presenting to the Jail Ward ED decreased from 639 (1988-1991) to 66 (1992-1995). The proportion of patients who sustained three or more bites decreased from 58.4% to 45.5%. The rate of vascular complications decreased from 7.5% to 1.6%, the rate of fractures decreased from 2.4% to 0, and the rate of cortical violations increased from 1.4% to 6.3%. The proportion of patients hospitalized decreased from 52.0% to 33.8%., Conclusion: K-9 dog bites are associated with significant injuries and complications. In this study, changes in law enforcement K-9 policy contributed to a significant decrease in the overall number of individuals bitten, the number of injuries and complications, and the proportion of patients hospitalized.

Objective: To review the types of injuries due to law enforcement (K-9) dog bites and address related management issues., Methods: A case series of law enforcement dog bite victims is reported and related literature reviewed., Results: Law enforcement dogs are taught a bite-and-hold technique for subduing individuals suspected of felony crimes. This bite-and-hold technique's greater applied force results in a unique spectrum of injuries, including deep puncture wounds, severe crush injuries, large tissue avulsions and lacerations, wounds necessitating surgical débridement, bony injuries ranging from cortical violations to displaced fractures, neurovascular damage, and other wounds at high risk for infection. The four reported cases highlight the types of injuries and complications associated with law enforcement dog bites., Conclusion: Attention to potential deep injuries of nerves, vessels, and the musculoskeletal system is essential with law enforcement dog bites. Injuries associated both with pursuit and arrest and with the bites themselves must be identified and assessed. Guidelines for the ED treatment of patients with law enforcement dog bite injuries are proposed.

We studied the effects of dietary calcium and lead exposure on lead toxicity, fetal and neonatal growth, erythropoiesis and blood pressure during pregnancy and lactation in rats. Pregnant Sprague-Dawley rats (n = 43) were randomly assigned to one of six treatment groups of 7-8 rats each. Half of the rats were fed diets of low (0.1%), normal (0.5%) or high (2.5%) calcium as calcium carbonate and exposed to 250 mg/L of lead in their drinking water for the duration of the pregnancy and for 1 wk of lactation. Three control groups were fed the same diets without lead exposure. Pups were studied at 1 d and 1 wk of age. Maternal and fetal blood and organ samples from the groups fed the low calcium diet had the highest lead concentrations, whereas the lowest lead concentrations were found in the groups fed the high calcium diet. Dam and pup hemoglobin concentrations, hematocrits, and body weights and lengths were reduced by lead exposure and by the high calcium diet. The latter also reduced organ iron concentrations and prevented lead-induced increases in free erythrocyte protoporphyrin. Dam systolic blood pressures during the third trimester of gestation were significantly higher in rats exposed to lead and fed the low calcium diet than in rats in the other five treatment groups. The results demonstrate that dietary calcium and lead exposure interact in rats to influence maternal blood pressure, erythropoiesis, and fetal and neonatal growth during pregnancy and lactation.

In this report, we describe the fractionation of crude axolemmal fractions from rat lower brainstem into subfractions enriched in markers for either periaxolemmal myelin or axolemma. These subfractions were isolated on density gradients as bands layering on 0.8M and 1.0M sucrose. Both subfractions consisted of unilamellar vesicles. Relative to myelin purified from the same starting material, the 0.8M subfraction was enriched in MAG, CNPase, carbonic anhydrase and Na+, K+ ATPase but was extremely low in PLP and MBP. In addition, this fraction exhibited a protein profile distinct from myelin. The 1.0M fraction was also highly enriched in Na+, K+ ATPase and had an overall composition similar to the 0.8M subfraction. However, it differed from the 0.8M subfraction by being low in MAG, CNPase, and carbonic anhydrase, but enriched in voltage-dependent Na+ channel, axon-specific fodrin, and MAP-1B. Based on these characteristics we concluded that the 0.8M and 1.0M subfractions were highly enriched in periaxolemmal myelin and axolemmal membrane, respectively. Plasmolipin10 was unique with equally high levels in myelin and in the 0.8M and 1.0M subfractions. Both subfractions were enriched, relative to myelin, in the alpha subunit of the GTP binding protein, Go, and the alpha subunit common to all G proteins, GA/1. Electrophysiology with membrane subfractions fused to lipid bilayers showed that both membranes contained sets of K+ and Cl- channels, which based on channel sizes and open times, are largely distinct from one another.

Plasmolipin is a plasma membrane proteolipid is a major myelin membrane component (Cochary et al., 1990). In this study we report the phylogenic expression of plasmolipin in the vertebrate nervous system. Using Western blot analysis with polyclonal antibodies, we have analyzed membrane fractions, including myelin, from elasmobranchs, teleosts, amphibians, reptiles, birds and mammals. On the basis of immune detection, plasmolipin appears to be restricted to the mammalian nervous system. Comparison of the central and peripheral nervous systems of mammals showed only minor differences in the level of plasmolipin in these two regions. Within mammals, little quantitative differences were observed when rat, human and bovine membrane fractions were compared. The late evolutionary expression of plasmolipin which results in its restriction to mammals makes it unique among the (major) myelin proteins. The potential physiologic significance of these data are discussed.

Male and female guinea pigs receiving, respectively, 100 and 280 mg/day Vitamin C throughout the duration of immunization showed enhanced humoral antibody production to bovine serum albumin (BSA) and, in castrated females, to penicilloyl-coupled guinea pig gamma-globulin. A significant degree of protection was afforded against fatal anaphylactic shock in passively sensitized males. Under appropriate conditions of sensitization with rabbit anti-HGG and challenge with human gamma-globulin, 8 of 20 unsupplemented animals died of shock, whereas in the group receiving 280 mg Na ascorbate/day for 4 days preceding passive transfer and again 60' before challenge, only 2 of 18 died. The rate of dose-dependent mortality observed when groups of passively sensitized animals were challenged with increasing doses of antigen was reduced in animals supplemented as above. Actively immunized guinea pigs were not protected by 5 daily doses of 280 mg Na ascorbate given prior to challenge. There were no significant differences in the total hemolytic activity of the serum nor in the C3 and C4 components of complement in immunized animals. There was no change in the concentration of Cl esterase in non-immunized controls, but immunization with BSA was followed by a rapid decline in Cl concentration, the decrease being greater in the ascorbate-treated group than in the unsupplemented controls, possibly reflecting a higher level of circulating immune complexes in the former case.

The main objective of this study was to determine whether the excitotoxic cholinesterase inhibitor soman increases the catabolism of phospholipids in rat brain. Injections of soman (70 micrograms/kg, s.c.), at a dose that produced toxic effects, increased the levels of both free fatty acids (175-250% of control) and free choline (250% of control) in rat cerebrum 1 h after administration. All fatty acids contained in brain phosphatidylcholine were elevated significantly including palmitic (16:0), stearic (18:0), oleic (18:1), arachidonic (20:4), and docosahexaenoic (22:6) acids. The changes observed were consistent with those reported to occur following ischemia and the administration of other convulsants. Pretreatment of rats with the anticonvulsant diazepam (4 mg/kg, i.p.) prevented both the signs of soman toxicity and the soman-induced increase of choline and free fatty acids. Diazepam alone did not affect the levels of choline or free fatty acids, cholinesterase activity, or soman-induced cholinesterase inhibition, suggesting that soman toxicity involves a convulsant-mediated increase in phosphatidylcholine catabolism. In addition, administration of the convulsant bicuculline, at a dose that produces seizures and increases the levels of free fatty acids in brain, significantly increased the levels of choline. Results suggest that excitotoxic events enhance the hydrolysis of phosphatidylcholine in brain as evidenced by a concomitant increase in the levels of choline and free fatty acids.

The role of cholinergic and non-cholinergic mechanisms in mediating organophosphate cholinesterase (ChE) inhibitor-induced elevations in choline levels in brain was investigated. The nerve agents soman and sarin, when administered to rats at doses greater than the IC50 for acetylChE inhibition, significantly increased the levels of choline and acetylcholine in both the striatum and hippocampus. The elevation in choline levels was evident 1 hr after injection with a maximal increase at 2 hr. Levels of choline returned to control by 4 hr. In contrast, the administration of diisopropyl phosphorofluoridate at doses greater than the IC50 for acetylChE inhibition increased the levels of acetylcholine, but did not alter the concentration of choline during the first 3 hr. Between 4 and 24 hr after injection, however, a significant decrease in choline levels was apparent. This effect persisted for 48 hr. When rats were pretreated with the anticonvulsant diazepam, the sarin- and soman-induced increases in choline levels were attenuated significantly. Results indicate that the organophosphates differentially alter the levels of choline in brain and suggest that the effect of soman and sarin to elevate choline levels is not a reflection of excessive cholinergic activity, but rather may be a consequence of the excitotoxic actions of these compounds.

The effect of chronic choline supplementation was studied on the toxicity of various pharmacological agents in rats and mice. Choline prevented both the incidence of seizures and the consequent lethality of nicotine, paraoxon, pentylenetetrazol, and strychnine. Nicotine toxicity was most markedly affected, and the prophylactic effects of choline were present in both rats and mice following either dietary or parenteral supplementation. Results suggest that chronic choline availability may alter neuronal membrane excitability.