Atmospheric Carbon and Transport - America (ACT-America) Data Sets: Description, Management, and Delivery.

The ACT-America project is a NASA Earth Venture Suborbital-2 mission designed to study the transport and fluxes of greenhouse gases. The open and freely available ACT-America data sets provide airborne in situ measurements of atmospheric carbon dioxide, methane, trace gases, aerosols, clouds, and meteorological properties, airborne remote sensing measurements of aerosol backscatter, atmospheric boundary layer height and columnar content of atmospheric carbon dioxide, tower-based measurements, and modeled atmospheric mole fractions and regional carbon fluxes of greenhouse gases over the Central and Eastern United States. We conducted 121 research flights during five campaigns in four seasons during 2016-2019 over three regions of the US (Mid-Atlantic, Midwest and South) using two NASA research aircraft (B-200 and C-130). We performed three flight patterns (fair weather, frontal crossings, and OCO-2 underflights) and collected more than 1,140 h of airborne measurements via level-leg flights in the atmospheric boundary layer, lower, and upper free troposphere and vertical profiles spanning these altitudes. We also merged various airborne in situ measurements onto a common standard sampling interval, which brings coherence to the data, creates geolocated data products, and makes it much easier for the users to perform holistic analysis of the ACT-America data products. Here, we report on detailed information of data sets collected, the workflow for data sets including storage and processing of the quality controlled and quality assured harmonized observations, and their archival and formatting for users. Finally, we provide some important information on the dissemination of data products including metadata and highlights of applications of ACT-America data sets.

Development of a higher power cooling system for lithium targets.

The accelerator based Boron Neutron Capture Therapy beam at the University of Birmingham is based around a solid thick lithium target cooled by heavy water. Significant upgrades to Birmingham's Dynamitron accelerator are planned prior to commencing a clinical trial. These upgrades will result in an increase in maximum achievable beam current to at least 3 mA. Various upgrades to the target cooling system to cope with this increased power have been investigated. Tests of a phase change coolant known as "binary ice" have been carried out using an induction heater to provide a comparable power input to the Dynamitron beam. The experimental data shows no improvement over chilled water in the submerged jet system, with both systems exhibiting the same heat input to target temperature relation for a given flow rate. The relationship between the cooling circuit pumping rate and the target temperature in the submerged jet system has also been tested.

A low tilt waveform in the transthoracic defibrillation of ventricular arrhythmias during cardiac arrest.

AIM: Most commercially available defibrillators utilise a high tilt waveform. Work in atrial fibrillation has shown improved defibrillation success using low tilt waveforms. We hypothesise that a novel low tilt biphasic waveform will be non-inferior to a standard tilt waveform whilst delivering lower energy for the defibrillation of ventricular arrhythmias. METHODS: Patients in cardiac arrest who experienced ventricular arrhythmias received shocks from a novel low tilt waveform defibrillator at 120J or a standard tilt waveform defibrillator at 150J. Resuscitation guidelines were followed as per Resuscitation Council UK, 2005. A shock was successful when the ventricular arrhythmia was terminated for ≥ 5s following shock delivery. RESULTS: A total of 113 cardiac arrest cases were included. The low tilt device was used for 56 cases and the standard tilt device for 57 cases. The presenting rhythm was ventricular fibrillation (VF) in 71.7% (81/113), pulseless electrical activity (PEA) in 15.9% (18/113), ventricular tachycardia (VT) in 9.7% (11/113), asystole in 1.8% (2/113) and narrow complex rhythm in 0.9% (1/113). The low tilt device resulted in first shock success in 86% (48/56 cases) vs. the standard tilt device first shock success of 77% (44/57 cases). There was no significant difference in first shock success between the two devices (p=0.36). CONCLUSION: The low tilt waveform used in this study demonstrated first shock success rates in keeping with a commercially available high tilt defibrillator which could result in less myocardial damage due to reduced energy requirements.

Takotsubo cardiomyopathy: an uncommon cause of ST segment elevation in intensive care.

A 63-year-old female developed respiratory failure and was admitted to the Intensive Care Unit for non-invasive ventilation, inotropic support and antibiotic therapy. The patient was initially stable but then suddenly deteriorated with acute pulmonary oedema requiring mechanical ventilation. An electrocardiogram showed an acute ST elevation myocardial infarction and the patient subsequently had an urgent coronary angiogram which revealed normal coronary arteries but apical ballooning characteristic of Takotsubo cardiomyopathy. A short review is provided of this relatively newly described heart syndrome which has the potential to present in numbers of intensive care patients. This case emphasises the importance of being aware of uncommon causes of acute ECG changes in the critically ill.

Does washing swabs increase the efficiency of red cell recovery by cell salvage in aortic surgery?

BACKGROUND AND OBJECTIVES: We investigated the contribution of swab washing to the efficiency of red cell recovery by intraoperative cell salvage (ICS) in 10 patients undergoing elective aortic aneurysm repair. MATERIALS AND METHODS: Volumes and haemoglobin (Hb) concentrations were recorded in the blood recovered by direct suction and from washed swabs, both before and after processing with a Haemonetics Cell Saver 5. RESULTS: The mean +/- standard deviation (SD) estimated blood loss was 991 +/- 403 ml, resulting in a mean +/- SD salvaged RBC volume of 380 +/- 124 ml. The median [interquartile (IQR) range] Hb collected from suction was 84.9 (61.8-131.4) g, of which 50.1 (45-71.5) g was returned to the patient after processing, a median yield of 68 (49-77)%. The swab wash produced a median (IQR) Hb of 39.4 (28.4-64.9) g, of which 26.2 (16.8-31) g was reinfused, a 67 (33-98)% yield. Swab wash thus contributed with a median (IQR) of 31 (24-39)% of the total RBC recovery. CONCLUSIONS: Washing swabs improves the efficiency of red cell recovery by ICS.

Respiratory muscle activity during REM sleep in patients with diaphragm paralysis.

The diaphragm is the main inspiratory muscle during REM sleep. It was hypothesized that patients with isolated bilateral diaphragm paralysis (BDP) might not be able to sustain REM sleep. Polysomnography with EMG recordings was undertaken from accessory respiratory muscles in patients with BDP and normal subjects. Patients with BDP had a normal quantity of REM sleep (mean +/- SD, 18.6 +/- 7.5% of total sleep time) achieved by inspiratory recruitment of extradiaphragmatic muscles in both tonic and phasic REM, suggesting brainstem reorganization.

A preliminary study on adaptive field-of-view tracking in peripheral digital subtraction angiography.

About two million peripheral angiographies are performed annually in the United States, hence a reduction in exposure would yield significant healthcare benefits. The synchronization of bolus traveling, the table motion, and the fluoroscopic imaging chain can be highly effective for dose reduction in Digital Subtraction Angiography (DSA) by minimizing the field-of-view according to the vascular anatomy of the region traveled by the bolus. The goal of this paper is to demonstrate the feasibility of adjusting the field-of-view while tracking the contrast bolus, thus reducing the dosage of both the bolus and the radiation. The speed of the bolus is respectively estimated in the systole and diastole stages. An EKG-gated Hammerstein model is used to predict the bolus chasing speed. A real-time algorithm is designed to extract the bolus dynamics, and define the field of view transversely and longitudinally. A limb stabilization technique is also presented to suppress any significant image misalignment. Our simulation results show that the proposed techniques are promising for clinical applications.

Enhanced activity of antisense phosphorothioate oligos against leishmania amastigotes: augmented uptake of oligo, ribonuclease H activation, and efficient target intervention under altered growth conditions.

Leishmania, a parasitic protozoan, infects human macrophages, often causing severe morbidity and mortality. The pathogenic form of this parasite, the amastigote, lives inside the acidic phagolysosomes of infected macrophages. In our attempt to develop anti-miniexon phosphorothioate oligodeoxyribonucleotides (S-oligos) as an alternative chemotherapy against Leishmania, we found that intracellular as well as 'axenic' amastigotes were more susceptible to these S-oligos than were the cultured promastigotes. Lower pH (4.5) and elevated temperature (35 degrees) of the medium were among the direct enhancing factors for killing. Addition of the cationic polypeptide poly-l-lysine (PLL) to the growth medium further enhanced the killing effect of the S-oligo at pH 4.5. The enhancement of specific ablation of mRNA expression was directly correlated to the increased leishmanicidal activity of the S-oligo. This was shown by the increased inhibition of luciferase activity expressed in transgenic Leishmania amazonensis promastigotes by anti-miniexon S-oligo or anti-luciferase S-oligo at acidic pHs and in the presence of PLL. The leishmanicidal effects of S-oligos at acidic pH and in the presence of PLL were related to increased uptake of the S-oligos under these conditions. The rate of S-oligo uptake was enhanced up to 15-fold at pH 4.5. The addition of PLL to the assay medium at acidic pH further enhanced the uptake of S-oligo up to 80-fold. RNase H is known to accentuate the antisense action of S-oligos. We found that at an elevated temperature RNase H activity in Leishmania cell extracts increased about 5-fold. Thus, enhanced uptake of S-oligos at the acidic pH of macrophage phagolysosomes and activation of RNase H may explain the efficient killing of the parasite in macrophages, both in tissue culture and in the animal model, by antisense miniexon oligonucleotide/PLL, when targeted directly to the parasite-containing phagolysosomes.

Increased efficacy of antileishmanial antisense phosphorothioate oligonucleotides in Leishmania amazonensis overexpressing ribonuclease H.

Ribonuclease H (RNase H), an enzyme that cleaves an RNA sequence base-paired with a complementary DNA sequence, is proposed to be the mediator of antisense phosphorothioate oligonucleotide (S-oligo) lethality in a cell. To understand the role of RNase H in the killing of the parasitic protozoan Leishmania by antisense S-oligos, we expressed an episomal copy of the Trypanosoma brucei RNase H1 gene inside L. amazonensis promastigotes and amastigotes that constitutively express firefly luciferase. Our hypothesis was that S-oligo-directed degradation of target mRNA is facilitated in a cell that has higher RNase H activity. Increased inhibition of luciferase mRNA expression by anti-luciferase S-oligo and by anti-miniexon S-oligo in these stably transfected promastigotes overexpressing RNase H1 was correlated to the higher activity of RNase H in these cells. The efficiency of killing of the RNase H overexpressing amastigotes inside L. amazonensis-infected macrophages by anti-miniexon S-oligo was higher than in the control cells. Thus, RNase H appears to play an important role in the antisense S-oligo-mediated killing of Leishmania. Chemical modification of S-oligos that stimulate RNase H and/or co-treatment of cells with an activator of RNase H may be useful for developing an antisense approach against leishmaniasis. The transgenic Leishmania cells overexpressing RNase H should be a good model system for the antisense-mediated gene expression ablation studies in these parasites.

Endoscopic assessment of oesophagitis: clinical and functional correlates and further validation of the Los Angeles classification.

BACKGROUND: Endoscopic oesophageal changes are diagnostically helpful and identify patients exposed to the risk of disease chronicity. However, there is a serious lack of agreement about how to describe and classify the appearance of reflux oesophagitis AIMS: To examine the reliability of criteria that describe the circumferential extent of mucosal breaks and to evaluate the functional and clinical correlates of patients with reflux disease whose oesophagitis was graded according to the Los Angeles system. METHODS: Forty six endoscopists from different countries used a detailed worksheet to evaluate endoscopic video recordings from 22 patients with the full range of severity of reflux oesophagitis. In separate studies, Los Angeles system gradings were correlated with 24 hour oesophageal pH monitoring (178 patients), and with clinical trials of omeprazole treatment (277 patients). RESULTS: Evaluation of circumferential extent of oesophagitis by the criterion of whether mucosal breaks extended between the tops of mucosal folds, gave acceptable agreement (mean kappa value 0.4) among observers. This approach is used in the Los Angeles system. An alternative approach of grouping the circumferential extent of mucosal breaks as occupying 0-25%, 26-50%, 51-75%, 76-99%, or 100% of the oesophageal circumference, gave unacceptably high interobserver variation (mean kappa values 0-0.15) for all but the lowest category of extent (mean kappa value 0.4). Severity of oesophageal acid exposure was significantly (p<0.001) related to the severity grade of oesophagitis. Preteatment oesophagitis grades A-C were related to heartburn severity (p<0.01), outcomes of omeprazole (10 mg daily) treatment (p<0.01), and the risk for symptom relapse off therapy over six months (p<0.05). CONCLUSIONS: Results add further support to previous studies for the clinical utility of the Los Angeles system for endoscopic grading of oesophagitis.

Association of adult achalasia and alacrima.

Achalasia is the best described motor disorder of the esophagus. Associations with familial glucocorticoid deficiency and alacrima (triple A syndrome) have been described in the pediatric population, but no attention has been paid to the possibility of this association in adults. Tear production was assessed in 20 patients with achalasia and 20 age- and sex-matched controls. Deficient tears were found in four achalasics compared with none among the controls (P < 0.05). This suggests that some variant of the triple A Syndrome (achalasia, alacrima, and adrenocortical insufficiency) may exist in adult patients with achalasia as well.

A look back at the year in health law.

The Bennett article takes us back to 1997 and reviews key legislators, regulations and judicial developments in Medicare, antitrust, tax and ERISA, all of which greatly impact the practice of health law.

Consultants' study leave--value for money?

The consultants in a single large acute hospital trust were given a personal allocation of 500.00 pounds for study leave and asked to supply reports on the purpose and value of that leave. The majority of consultants (82%) took leave during the 12-month period at an average cost of 182.80 pounds for each episode. Most was regarded of value and the majority was shared with other members of staff.

The endoscopic assessment of esophagitis: a progress report on observer agreement.

BACKGROUND & AIMS: The study and management of reflux esophagitis require an endoscopic classification system founded on esophageal lesions that can be reproducibly identified. The aim of this study was to investigate interobserver agreement for the identification of endoscopic lesions typical of reflux esophagitis. METHODS: Paired comparisons of observers' descriptions were obtained. Seventeen endoscopists assessed 100 still images, and 42 endoscopists, including 13 endoscopists in training, assessed 23 endoscopic video recordings. In a third, ancillary study, using a simpler evaluation sheet, 219 gastroenterologists recorded their assessments of 20 still images. RESULTS: The agreement between endoscopists was similar for still images and video recordings. Agreement between experienced endoscopists was acceptable to good for recognition of minimal changes (erythema, friability, mucosal edema; kappa = 0.46 to kappa = 0.8), mucosal breaks (discretely, demarcated areas of slough or erythema; kappa = 0.84), and complications (ulceration, kappa = 0.92; stricturing, kappa = 0.80; columnar metaplasia, kappa = 0.81), although there was poor agreement when the circumferential extent and number of mucosal breaks were assessed. However, total circumferential extent of the mucosal break had a kappa value of 0.59. Agreement between inexperienced endoscopists was poor for recognition of minimal changes but was good for recognition of complications (kappa, 0.70-0.90). CONCLUSIONS: Endoscopists can identify mucosal breaks confined to a mucosal fold and lesions that extend throughout the esophageal circumference. Complications of reflux disease can be reproducibly recorded. Criteria for assessing the number of mucosal breaks and their radial extent must be defined more clearly, as must the features of minimal change esophagitis.