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A common feature of fluorescent sensing materials for detecting chemical warfare agents (CWAs) and simulants is the presence of nitrogen-based groups designed to nucleophilically displace a phosphorus atom substituent, with the reaction causing a measurable fluorescence change. However, such groups are also basic and so sensitive to acid. In this study we show it is critical to disentangle the response of a candidate sensing material to acid and CWA simulant. We report that pyridyl-containing sensing materials designed to react with a CWA gave a strong and rapid increase in fluorescence when exposed to Sarin, which is known to contain hydrofluoric acid. However, when tested against acid-free diethylchlorophosphate and di-iso-propylfluorophosphate, simulants typically used for evaluating novel G-series CWA sensors, there was no change in the fluorescence. In contrast, simulants that had been stored or tested under a standard laboratory conditions all led to strong changes in fluorescence, due to acid impurities. Thus the results provide strong evidence that care needs to be taken when interpreting the results of fluorescence-based solid-state sensing studies of G-series CWAs and their simulants. There are also implications for the application of these pyridyl-based fluorescence and other nucleophilic/basic sensing systems to real-world CWA detection. Chemical warfare agents and simulants are commonly detected with fluorescent sensing materials containing nitrogen-based groups, however these groups’ basicity can cause false positives in the presence of acids. Here, the authors disentangle the response of pyridyl-containing sensing materials to acid-containing and acid-free Sarin and simulants.

Sarin is a highly toxic nerve agent classified by the Chemical Weapon Convention as a Schedule 1 chemical with no use other than to kill or injure. Moreover, in recent times, chemical warfare agents have been deployed against both military and civilian populations. Chemical warfare agents always contain minor impurities that can provide important chemical attribution signatures (CAS) that can aid in forensic investigations. In order to understand the trace molecular composition of sarin, various analytical approaches including GC-MS, LC-MS and NMR were used to determine the chemical markers of a set of sarin samples. Precursor materials were studied and the full characterisation of a synthetic process was undertaken in order to provide new insights into potential chemical attribution signatures for this agent. Several compounds that were identified in the precursor were also found in the sarin samples linking it to its method of preparation. The identification of these CAS contributes critical information about a synthetic route to sarin, and has potential for translation to related nerve agents.

The first discrete bimetallic europium(iii)/copper(ii) complex for the fast, sensitive and selective luminescent detection of both aqueous and gaseous hydrogen sulfide has been developed. The chemosensor displayed an impressive response time of 30 seconds and a low theoretical limit of detection (100 ppb) for gaseous hydrogen sulfide.

The addition of G- and V-series organophosphorus chemical warfare agents and simulants to a paper-based assay of a dual-luminescent Ir(iii)/Eu(iii) dyad generated different emissive responses between the classes and compound types. The emission responses are complex and based not only on altering the balance between red Eu(iii)-based and blue Ir(iii)-based luminescent components, but also incorporate other factors such as analyte volatility, concentration and UV absorption. The extent of this emission colour change was analysed colorimetrically and related to the change in RGB output over time.

We present the construction of a new white-light coronal brightness index (CBI) from the entire archive of observations recorded by the Large Angle Spectrometric Coronagraph (LASCO) C2 camera between 1996 and 2017, comprising two full solar cycles. We reduce all fully calibrated daily C2 observations of the white light corona into a single daily coronal brightness observation for every day of observation recorded by the instrument, with mean daily brightness values binned into 0.1 Rsun radial x 1 degree angular regions from 2.4 -- 6.2 Rsun for a full 360-degrees. As a demonstration of the utility of the CBI, we construct a new solar irradiance proxy that correlates well with a variety of direct solar irradiance observations, with correlations shown to be in the range of 0.77-0.89. We also present a correlation mapping technique to show how irradiance correlations depend on, and relate to, coronal structure/locations, and to demonstrate how the LASCO CBI can be used to perform long-term "spatial correlation" studies to investigate relationships between the solar corona and any arbitrary concurrent geophysical index. Using this technique we find possible relationships between coronal brightness and plasma temperature, interplanetary magnetic field magnitude and (very weakly) proton density., Comment: 35 pages, 9 Figures. Accepted to Solar Physics

Aims. We present the design and pre-launch performance of the Solar Orbiter Heliospheric Imager (SoloHI) which is an instrument prepared for inclusion in the ESA/NASA Solar Orbiter mission, currently scheduled for launch in 2020.Methods. The goal of this paper is to provide details of the SoloHI instrument concept, design, and pre-flight performance to give the potential user of the data a better understanding of how the observations are collected and the sources that contribute to the signal.Results. The paper discusses the science objectives, including the SoloHI-specific aspects, before presenting the design concepts, which include the optics, mechanical, thermal, electrical, and ground processing. Finally, a list of planned data products is also presented.Conclusions. The performance measurements of the various instrument parameters meet or exceed the requirements derived from the mission science objectives. SoloHI is poised to take its place as a vital contributor to the science success of the Solar Orbiter mission.

In August 2018, the U.S. Centers for Disease Control and Prevention (CDC) noted an increased number of reports of patients in the U.S. having symptoms clinically compatible with acute flaccid myelitis (AFM). AFM is characterized by rapid onset of flaccid weakness in one or more limbs and distinct abnormalities of the spinal cord gray matter on magnetic resonance imaging (MRI). Clinical and laboratory data suggest that AFM is associated with an antecedent viral infection. AFM may be difficult to differentiate from other causes of paralysis and, given that it is rare, has the potential to be overlooked. This case highlights important clinical characteristics of AFM and emphasizes the importance of including AFM in the differential diagnosis when evaluating active duty service members and Military Health System (MHS) beneficiaries presenting with paralysis.

In order to develop new, low toxicity and readily accessible supramolecular simulants for V-series organophosphorus chemical warfare agents (OP CWAs) a series of organothiophosphate compounds, that are structurally analogous to the V-series OP CWAs, were designed and synthesized. Solution spectroscopic studies (luminescence and UV-vis) into the binding behaviors of these compounds and some organothiophosphate pesticides with the simple model trivalent lanthanide complex [Eu(phen)2(NO3)3]·3H2O were performed and association constants (Kassoc) determined. Binding behaviors of these compounds with other OP CWAs and simulants investigated previously in analogous studies are presented and the implications of this in the context of OP CWA and related chemical sensing are discussed.

Solution spectroscopic investigations into the interactions of eight potential bidentate V-series organophosphorus chemical warfare agent (OP CWA) simulants with [Eu(phen)2(NO3)3]·2H2O demonstrated that the chemical and structural composition of the secondary binding site within the simulant was of paramount importance. Only simulants containing both phosphoryl/phosphonyl and amine moieties generated analogous spectroscopic behaviours to V-series OP CWAs seen in previous studies. The results demonstrated that the bidentate chelation mechanism was driven by the phosphoryl/phosphonyl moieties and that the presence of the amine moieties induced a significant secondary dynamic luminescence quenching mechanism. The binding modes of the simulants VO and TEEP to trivalent lanthanides (Eu and La) were further investigated using 1H and 31P NMR spectroscopic titrations and kinetic IR experiments. VO, with both the phosphonyl and amine binding sites was found to be the most appropriate simulant for V-series OP CWAs in supramolecular studies with trivalent lanthanide ions and we recommend VO for use in supramolecular studies of this type.

Interaction of the V-series chemical warfare agent simulant ‘VO’ with Eu(III) results in selective quenching of the red Eu-based emission component from a dual-luminescent (blue/red) Ir(III)/Eu(III) dyad, resulting in a colour change in the luminescence from red to blue in the presence of the simulant.

Background Wide variations exist in healthcare expenditures, though most prior studies have assessed aggregate utilization. We sought to examine healthcare utilization variation in New York State by assessing hospitals in peer groups of similar capabilities. Methods Using charge data in New York State from the 2008 Statewide Planning and Research Cooperative System (SPARCS) and cost-to-charge ratios at the cost-center level drawn from Institutional Cost Reports, we calculated total, routine, and ancillary costs for patients discharged with an acute myocardial infarction (AMI) diagnosis in 2008. We assessed the correlation of these cost data to Hospital Referral Region (HRR) Medicare reimbursement data from the 2007 Dartmouth Atlas of Health Care. After describing hospital level cost variability, we examined characteristics associated with higher costs within peer groups of similar cardiac care capabilities. Results We found greater costs in hospitals providing the highest level of cardiovascular services, with cardiac surgery capable hospitals and non-invasive hospitals having total costs of $21,166 and $9268 per AMI discharge, and ancillary costs of $12,006 and $4167 per AMI discharge, respectively. Substantial variability in utilization existed in all levels of hospitals and across individual departmental cost centers. The two factors most frequently associated with higher total and ancillary costs across peer groups were patient case mix index and major or minor teaching status. Conclusions Significant variation in cost per AMI discharge exists even within peer groups of hospitals with similar cardiac care capabilities. Implications These findings support measurement and analysis at the hospital level to further understand the reasons for variation in utilization.

Fundamental supramolecular interactions of the G-series organophosphorus (OP) chemical warfare agent (CWA) sarin, and various simulants, with simple lanthanide complexes of the type Ln(phen)2(NO3)3·(H2O)x (where phen = 1,10-phenanthroline; 1: Ln = Eu(III), x = 3 and 2: Ln = Tb(III), x = 2) have been elucidated by spectroscopic investigations. Luminescent and UV-Vis results show only minimal fluorescence quenching occurring as a result of a dynamic mechanism. These results have been compared with previously presented V-series OP CWA data demonstrating that the luminescence quenching of the two series occurs with differing magnitudes and mechanisms. Agent-simulant correlations for use with lanthanide complexes are also discussed which are of critical importance for informing the design and construction of efficient, advanced and regenerable supramolecular sensing systems.

There have been significant advances in understanding how the fragile X gene (FMR1) can lead to distinct neurological syndromes. Clinical features of two disorders – fragile X syndrome and fragile X-associated tremor ataxia syndrome (FXTAS) – are highlighted in this article. These two disorders – one a neurodevelopmental disorder, the other a neurodegenerative disorder – are caused by a single expanded CGG repeat sequence within the FMR1 gene. Minor differences in repeat length result in the markedly different phenotypes. Understanding the action of FMR1 in FXTAS and fragile X syndrome has yielded significant insights into the genetics of neurodegeneration. Moreover, the genetic model in FXTAS is similar to several other neurologic genetic disorders, suggesting there are common pathways shared by many phenotypically diverse progressive neurodegenerative disorders. Finally, it is possible that targeted therapies for disorders such as FXTAS may also be effective in other neurodegenerative disorders that share similar mechanisms of pathogenesis.

This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (August 2017) in accordance with the publisher’s archiving policy, In the course of providing assistance to legal counsel in a matter that involved the analysis of firearms propellant by gas chromatography/mass spectrometry it was noticed that phenoxazine was reported as a component of 0.22 calibre propellant that contained diphenylamine as the stabiliser. The research was conducted to find how phenoxazine was formed. The results showed that the compound was not phenoxazine but a diphenylamine derivative 4-(phenylimino) cyclohexa-2,5-dien-1-one that formed in the injection port of the gas chromatograph. In addition a second artefact was found to form in the ion source of the mass spectrometer. While the presence of the artefacts does not affect the ability to identify particles as propellant they may impact on comparison with source ammunition.

Background Lyme disease is the most common vector-borne disease in the United States and is caused by infection with the spirochete Borrelia burgdorferi . In children, neuroborreliosis usually presents as peripheral facial nerve palsy and lymphocytic meningitis and only rarely is associated with cranial polyneuritis. Patient Description We present a 15-year-old with tinnitus, hearing loss, and facial nerve palsy in the setting of acute, severe right arm pain and a several week history of malaise and headache. Lumbar puncture was notable for lymphocytic pleocytosis. Serologic testing demonstrated positive Lyme antibody and a positive immunoglobulin M Western blot. Immunofluorescent assay of cerebrospinal fluid was also positive for anti-Lyme immunoglobulin M. Audiologic testing revealed mixed, right-sided hearing loss. Neuroimaging demonstrated cranial polyneuritis and right-sided cochlear inflammation. The patient was treated with parenteral ceftriaxone with resolution of his symptoms at close follow-up. Discussion Neuroborreliosis with radiculopathy, lymphocytic meningitis, and cranial polyneuritis is a rare presentation of pediatric Lyme disease. Additionally, cochlear inflammation along with cranial nerve VIII inflammation may contribute to hearing loss in patients with neuroborreliosis.

Organophosphorus chemical warfare agents (OP CWAs) are potent acetylcholinesterase inhibitors that can cause incapacitation and death within minutes of exposure, and furthermore are largely undetectable by the human senses. Fast, efficient, sensitive and selective detection of these compounds is therefore critical to minimise exposure. Traditional molecular-based sensing approaches have exploited the chemical reactivity of the OP CWAs, whereas more recently supramolecular-based approaches using non-covalent interactions have gained momentum. This is due, in part, to the potential development of sensors with second-generation properties, such as reversibility and multifunction capabilities. Supramolecular sensors also offer opportunities for incorporation of metal ions allowing for the exploitation of their unique properties. In particular, trivalent lanthanide ions are being increasingly used in the OP CWA sensing event and their use in supramolecular sensors is discussed in this Minireview. We focus on the fundamental interactions of simple lanthanide systems with OP CWAs and simulants, along with the development of more elaborate and complex systems including those containing nanotubes, polymers and gold nanoparticles. Whilst literature investigations into lanthanide-based OP CWA detection systems are relatively scarce, their unique and versatile properties provide a promising platform for the development of more efficient and complex sensing systems into the future.

Investigations into V-agent interaction with 1,10-phenanthroline nitrate Ln(III) complexes (Eu and Tb) were carried out using luminescence and UV-Vis spectroscopy. Addition of several equivalents of agent resulted in the loss of luminescence intensity and the observation of free 1,10-phenanthroline by UV-Vis. We propose a displacement mechanism in which the V-agent acts as a bidentate ligand to the lanthanide ion. Association constants were determined by luminescence titrations and found to be 10(5) mol(-1) dm(3).

Organophosphorus chemical warfare agents (OP CWAs) are potent acetylcholinesterase inhibitors that can cause incapacitation and death within minutes of exposure, and furthermore are largely undetectable by the human senses. Fast, efficient, sensitive and selective detection of these compounds is therefore critical to minimise exposure. Traditional molecular-based sensing approaches have exploited the chemical reactivity of the OP CWAs, whereas more recently supramolecular-based approaches using non-covalent interactions have gained momentum. This is due, in part, to the potential development of sensors with second-generation properties, such as reversibility and multifunction capabilities. Supramolecular sensors also offer opportunities for incorporation of metal ions allowing for the exploitation of their unique properties. In particular, trivalent lanthanide ions are being increasingly used in the OP CWA sensing event and their use in supramolecular sensors is discussed in this Minireview. We focus on the fundamental interactions of simple lanthanide systems with OP CWAs and simulants, along with the development of more elaborate and complex systems including those containing nanotubes, polymers and gold nanoparticles. Whilst literature investigations into lanthanide-based OP CWA detection systems are relatively scarce, their unique and versatile properties provide a promising platform for the development of more efficient and complex sensing systems into the future.

A retrospective case-cohort study was formed with 48,762 children with Autistic Spectrum Disorders (ASD) aged 2-18 years enrolled in the Military Health System from 2000-13. Children with ASD were matched 1:5 by age, gender, and enrollment time to children without ASD. International Classification of Diseases, 9th Revision, Clinical Modification and Current Procedural Terminology codes were extracted to examine associations and co-morbidities. Of perinatal conditions, seizures in the first 90 days of life were most highly associated with ASD. Specific seizure types such as absence seizures and infantile spasms have high associations with ASD, with children with ASD 4 times more likely to have seizures labeled as intractable. Seizures also account for most of the 17% increase in injury risk. Obesity and its complications are twice as common in children with ASD. However, children with ASD also are at risk for deficiencies in macro- and micronutrients, such as iron and vitamin D. Other comorbid conditions can be masked by ASD and lead to complications of missed or late diagnoses. Eosinophilic esophagitis is most strongly associated with a feeding disorder and not with ASD itself. Children with ASD who develop appendicitis are more likely to have perforation and sepsis, and those with otitis media are more likely to have perforation and cholesteatoma. Sleep disorders have a prevalence of 30% in children with ASD, and they are more likely to undergo procedures for their sleep issues. ASD is associated with multiple conditions throughout childhood, and the presence of ASD affects how clinicians diagnose and treat these conditions. These results provide clinicians with data to better screen and manage ASD patients.

Phase-change memory devices fabricated using MOCVD-deposited 30% Ge, 20% Sb, and 50% Te atomic composition, GST325 alloy, are fully characterized. In 100-nm-size test devices, a more than 2x reduction of reset current and set resistance were demonstrated compared with equivalent devices using PVD-deposited GST225. The devices show set speeds of 175-260 ns and a ten-year data-retention temperature of 102°C, comparable with devices made using a PVD GST225 alloy. Cycle endurance of up to 7 × 109 was also demonstrated.

Phase-change memory alloys based on germanium, antimony, and tellurium with SiO2 nanophase dielectric inclusions are investigated for material and electrical properties. The new alloys are prepared by cosputtering with a SiO2 target creating nanophase dielectric inclusions. The addition of the dielectric inclusions significantly increases the crystallization temperature without affecting the required programming current. In memory device configurations, the nanocomposite alloys exhibit a ten-year data retention above 200°C and a cycle life greater than 1 × 107 cycles while maintaining the SET programming speed of 250 ns.

Background: Given the rising costs of medical care in the US, efforts at improving quality of care seek also to control expenditures with high-value healthcare - better quality and lower cost. Prior studies have used variations in Medicare reimbursements at the regional level, rather than individual hospital costs, to account for the unique patient case-mix of individual hospitals. To date, higher expenditures have been unrelated to clinical outcomes. We sought to explore variation using costs, rather than payment, and to study the links between inpatient hospital Medicare expenditures, hospital costs, and Medicare's quality indicators. Methods: In New York State, we analyzed hospital discharges in 2008 for acute myocardial infarction (AMI) in the New York State Planning and Resource Cooperative System (SPARCS) database. Using SPARCS reported hospital charges and the Medicare cost-to-charge ratio we calculated, at the individual hospital level, the total costs and departmental-level ancillary costs (costs of specific hospital services) for patients discharged with a primary diagnosis of AMI. We compared total inpatient cost to Dartmouth Atlas of Health Care Medicare inpatient reimbursements, analyzed variation in ancillary costs by hospital cardiac program peer groups (based on highest-level capability), and related total costs to Medicare AMI quality scores. Results: The study analyzed data that represented 56,000 AMI cases in 150 hospitals. When comparing total costs to Medicare inpatient reimbursements, there was high correlation with an R-squared of 0.84. The mean ancillary costs per AMI discharge were $12,006 [standard deviation (SD) $4,301, coefficient of variation (COV) 0.358] for cardiac surgery-capable, $6,452 [SD $1,732, COV 0.268] for percutaneous coronary intervention-capable, $5,104 [SD $2,548, COV 0.499] for diagnostic catheterization-capable, and $4,167 [SD $2,756, COV 0.661] for non-invasive hospitals. There was no overall correlation between AMI total costs and Medicare composite AMI quality scores, yet 19.7% (28 out of 142 hospitals with AMI quality score reporting in 2008) of hospitals had above average quality scores, with lower than average total costs. Conclusions: In AMI hospitalizations, regional Medicare reimbursements have a strong correlation with total hospital costs. Hospitals vary greatly in their costs of caring for AMI patients. Though there is no overall association between the level of costs and performance on standardized quality scores, high-value healthcare in AMI does exist with numerous high-quality, low-cost hospitals. Examining the expenditures of these hospitals may be useful in identifying patterns of quality and cost-effective patient care. These findings support that high-spending is not necessary for high-quality, and that high-value healthcare can be realized.

MOCVD (Metal-organic Chemical Vapor Deposition) has been investigated extensively to achieve smooth and conformal deposition of GST (GeSbTe) films. The studies are focused on filling confined cells as well as improving material properties for high performance PCM (Phase Change Memory) applications. Our MOCVD process allows GST alloys to fill 15nm hole structures. By tailoring the MOCVD process and GST compositions, MOCVD GST alloys exhibit superior material properties compared to Ge 2 Sb 2 Te 5 PVD (Physical Vapor Deposition) alloys in terms of higher device speeds and lower reset currents. PCM devices made from optimized MOCVD GST alloys demonstrate set-speed of 12ns in ∼100nm size devices, which is more than 10X faster than the typical 150–200ns set-speed observed for devices of similar size made from benchmark PVD Ge 2 Sb 2 Te 5 alloys. PCM devices made from the 12ns high speed GST alloys by the MOCVD process also exhibit programming cycle endurances greater than 5×108 at a 20ns set time. In addition, devices made from MOCVD GST alloys can also be made to have ∼3X lower reset currents than devices made from PVD GST alloy of same compositions.

Phase change memory devices were originally reported by S. R. Ovshinsky [1] in 1968. A 256-bit phase-change memory array based on chalcogenide materials was reported in 1970 [2], Recent advances in phase change materials, memory device designs, and process technology have resulted in significant advances in phase change device performance, and a new memory device, called Ovonic Unified Memory (OUM), has been developed. This paper will discuss various device and materials characteristics of OUM phase change memory materials of interest in applications for nonvolatile high-density memories. These materials are generally Te chalcogenide based, exploiting the congruent crystallization of the FCC phase and the associated reduction in resistivity that results from crystallization from the quenched amorphous state. Data storage is a thermally initiated, rapid, reversible structural phase change in the film. While rewriteable DVD disks employ laser heat to induce the phase change and modulate reflectivity, OUM technology uses a short electrical current pulse to modulate resistivity. The device geometry and thermal environment dictate the power and energy required for memory state programming. We will review the device structure, characterization data, device performance, and reliability as well as device modeling results. Characteristics of key material and device performance metrics such as crystallization and amorphization programming speed will be presented. Programming algorithms will be discussed for optimizing operating margin for high-density applications. Data retention characteristics will be reviewed along with means for accelerated statistical evaluation. Potential high-density memory array data disturb issues will be identified, and their impact on scalability will be assessed. Scaling attributes and issues will be reviewed.

The health care system in the United States has been experiencing rapid change for decades. Beginning after World War II, the health care system grew and expanded. Change was driven by advances in technology, shifting demographics, and increases in the supply of physicians and hospitals, all fueled by supportive public policy and governmental funding. While change continues today, new dynamics drive the direction of change. These new dynamics generally share a common theme of cost containment. The purchasing power of buyers, both industry and government, has overshadowed the historical power of providers. Managed care financing mechanisms have changed provider behavior by introduction of utilization management mechanisms and shifted incentives through assumption of insurance risk by providers. The role of patients has also changed as the consumer has become more knowledgeable and empowered. There are large and growing numbers of uninsured Americans. There is growing discontent around the quality of care being provided by the health care system. All these factors, and more, drive today's changes in the organization, delivery, and financing of health care in the United States. However, the change we see in each community varies in terms of its pace and in how the parts of the health care delivery and financing system have organized and reorganized. There appears to be no clearly articulated public policy that is shaping the structure and function of the health care system of the future. This symposium explores the issues behind the variability of the change observed in the health care system from community to community, and particularly to place Syracuse, New York, in the context of these changes.

The health care system in the United States has been experiencing rapid change for decades. Beginning after World War II, the health care system grew and expanded. Change was driven by advances in technology, shifting demographics, and increases in the supply of physicians and hospitals, all fueled by supportive public policy and governmental funding. While change continues today, new dynamics drive the direction of change. These new dynamics generally share a common theme of cost containment. The purchasing power of buyers, both industry and government, has overshadowed the historical power of providers. Managed care financing mechanisms have changed provider behavior by introduction of utilization management mechanisms and shifted incentives through assumption of insurance risk by providers. The role of patients has also changed as the consumer has become more knowledgeable and empowered. There are large and growing numbers of uninsured Americans. There is growing discontent around the quality of care being provided by the health care system. All these factors, and more, drive today's changes in the organization, delivery, and financing of health care in the United States. However, the change we see in each community varies in terms of its pace and in how the parts of the health care delivery and financing system have organized and reorganized. There appears to be no clearly articulated public policy that is shaping the structure and function of the health care system of the future. This symposium explores the issues behind the variability of the change observed in the health care system from community to community, and particularly to place Syracuse, New York, in the context of these changes.

health-care practitioners should be aware of how their equipment and practices can increase the patient's risk for noise-induced hearing loss.We conducted this study to determine the type of noise produced by humidifiers and nebulizers used with hoods in the neonatal intensive care unit (NICU). We performed octave waveband analysis to determine sound intensities and frequencies because degree of hearing loss from noise exposure is related to the intensity of sound, frequency of sound and duration of exposure.We studies 4 simple humidifiers, 3 heated humidifiers, and 4 nebulizers. Sound levels were measured at various frequencies, flows, and water levels using Peace and Shiley oxygen hoods.The findings show that sound levels were significantly louder (p.0.001) for nebulizers compared to humidifiers. Aquapak nebulizers pose the greatest risk for hearing loss because they produce sound at the highest frequencies and volumes. The peak sound levels of humidifiers not only were significantly lower but also occurred at the lowest sound frequencies, which are the least damaging to hearing. Sound levels were generally higher across sound frequencies at higher flows and with the Peace Hood.We conclude that heated humidifiers produce lowest sound intensities at the lowest sound frequencies and, consequently, are most appropriate for use in the NICU.

To produce a chronic, ischemic heart failure preparation of controllable severity, plastic microspheres (6 to 14 μ in diameter) were injected into the left main coronary artery of unanesthetized calves. Two dose levels were used (4 and 5 mg/kg, Groups I and II, respectively). Hemodynamic and electrocardiographic changes were not observed during the microsphere infusion. Arterial-coronary sinus lactate differences shifted from positive control values (mean +5.3 mg/ 100 ml) to negative during and throughout the injection (mean −6.4 mg/100 ml). Significant hemodynamic abnormalities at rest (Group II only) were first noted on postinfusion day 1, and unaccompanied by subsequent significant physiologic recovery. These included an increase in left ventricular end-diastolic pressure (+18 to 21 mm Hg), reduction in stroke volume (−32 percent), cardiac output (−25 percent), dP/dt (−22 percent), mean ejection rate (−18 percent) and left ventricular ejection time, and a prolongation of preejection period. Cardiac response to angiotensin-induced stress was impaired in both test groups. Mean heart weight and left ventricular wall thickness increased by 65 and 45 percent, respectively, in both groups. Histopathologic examination demonstrated microinfarcts widely distributed throughout the myocardium supplied by the left coronary artery at various stages of healing, sometimes in the same heart, with typical time-dependent morphologic characteristics. The myocardial fibers were hypertrophied. In addition, atypical areas were found on glycogen selective staining. The results suggest that the extent of microcirculatory ischemia and infarction determines the degree of myocardial impairment at rest and during stress irrespective of compensatory hypertrophy.

Fourteen 3-month-old calves weighing from 90 to 100.5 kg. were studied hemodynamically while in the standing resting state. Measurements were made of left ventricular (implanted transducer) and arterial pressure (catheter), aortic flow (electromagnetic probe), and the electrocardiogram. The following average results were found: left ventricular pressure (134/9 mm. Hg); arterial pressure (134/94 mm. Hg); and heart rate (101 beats/min.). From this basic data several derivations were made. These include (with their average values): Stroke volume (84 cc.) and stroke index (40 cc./m.2); (2) cardiac output (8.4 liters/min.) and cardiac index (3.9 liters/min./m.2); (3) maximum rate of pressure rise (1719 mm. Hg/sec.); (4) mean ejection rate (380 cc./sec.); and (5) stroke work (130 gm.-m) and stroke power (588 gm.-m/sec.). Various systolic and diastolic time intervals were also measured, regression equations derived, and the resultant regression lines plotted against heart rate. These included: electromechanical systole (QS2); left ventricular ejection period (LVET); the preejection period (PEP); diastole (D); and the ratio of systole to diastole (QS2/D). The results suggest that the hemodynamic resemblance to man is indeed very close. In addition, the calibration, performance, and utilization of an implantable ventricular pressure transducer is discussed. The data provide useful information for the utilization and evaluation of circulatory and cardiac assist devices in the calf.

The high‐temperature heat contents of scandium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, and lutetium were measured from 0°C to at least the melting points of these metals. The specific heats, heats of transition, heats of fusion, and related thermodynamic functions were calculated. The smoothed values of H°T—H°298.15, (H°T—H°298.15)/T, S°T, and − (F°T—H°298.15)/T are tabulated at 100° intervals. An examination of the entropies of transition and fusion of all of the measured rare‐earth metals shows that the entropy of the fcc(or hcp)⇄bcc transition depends upon the number of valence electrons and the entropy of fusion decreases with increasing rare‐earth‐metal size. The electronic dependence of the entropy of transformation has also been observed to hold for other metals undergoing similar transformations.

We measured the resistance in nine complete ventilator circuits, partial circuits and 7, 8, and 9 mm ID endotracheal tubes at flow rates of 20 to 120 liters per minute. We found a statistically significant (p less than 0.01) increase in resistive pressure with increases in flow rate, as the diameter of the ETT decreased, and as each component of the ventilator circuit was added to the ETT. There was a curvilinear increase in resistive pressure to increase in flow rate. However, when resistances were computed, the Bennett cascade "circuit" created higher resistance at 20 lpm than at flow rates up to 120 lpm. The Bennett cascade humidifier added the greatest resistive pressure, 3.5 to 8.5 cm H2O, the Engstrom Edith, 0.5 to 6.5 cm H2O, and the Conchapak added the least, 0.0 to 2.5 cm H2O at flow rates of 20 to 120 lpm. After all the components of the ventilator circuit were attached to the ETTs, there was approximately a 97 to 450 percent increase in resistive pressure compared to the resistive pressure created by the ETTs alone.

Failure analysis of the CK12 capacitor indicated three failure modes: (1) transient increases in dissipation factor; (2) permanent changes in dissipation factor; and (3) permanent changes in dissipation factor accompanied by a change in capacity. From a failure effects analysis, the magnitude of change would not effect a filtering or by-pass application. A coupling application is more critical and each circuit would have to be treated individually. Failure mechanisms for the first two failure modes are the result of moisture and salt. The third failure mode has a mechanism which may be the result of an aging phenomenon (physical strain relief). Acceleration test planning was completed. (Author)

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