Characterization of Secondary Organic Aerosol (SOA) formed by the Reaction of β-caryophyllene, Soot and Ozone: Climate Impact

Diesel soot (black carbon, BC) is an important light absorbing aerosol component in atmosphere that can cause tropospheric heating. Laboratory studies have found it to be unreactive to ozone at ambient temperature. The low uptake coefficient i.e., γ 300 K = 2× 10-7 , of the soot-O3 reaction indicates a low probability of irreversible O3 loss from gas phase to surface-adsorbed product (Particle phase). This shows clearly that at low temperature soot is not reactive with atmospheric oxidants. In contrast, sesquiterpenes (SQT) such as β-caryophyllene (C15H24), which are produced primarily by plants, are extremely reactive with ozone. For example, the residence time of β- caryophyllene in the atmosphere is only 2 min in the presence of 60 ppb ozone. Thus, ozonolysis reaction of β-caryophyllene is expected to be a significant source of biogenic secondary organic aerosols. These oxidized products may condense onto soot particles, and a question arises as to how they will partition between the soot surface, vapor phase, and aqueous aerosol phases. Liquid chromatography- mass spectrometry (LC/MS), Fourier transform infrared (FTIR) and UVVis spectroscopies are being used to study the β- caryophyllene-dark ozonolysis reaction at low ozone levels (40-60 ppb). Products identified include low molecular weight highly volatile and water soluble products such as formaldehyde, acetaldehyde, acetone, and acetic acid. Also identified are high molecular weight components (~350 Dalton) with lower water solubility and vapor pressures. The SOA coatings of these SQTs on soot are being evaluated to determine their hygroscopicity. As these compounds absorb in the IR and UV-Vis they can add to radiative forcing by submicron aerosols and need to be better understood for climate modeling

Solvent extraction study of the thorium nitrate, nitric acid, and tributyl phosphate-dodecane system: density and acidity relationships

A solvent extraction study to determine equilibrium conditions of thorium nitrate-nitric acid with 30% tributyl phosphate in normal dodecane has been completed. Experimental conditions studied were 30 to 60{sup 0}C, 0.05 to 1.5 M Th(NO{sub 3}){sub 4}, and 0.0 to 3.0 M HNO{sub 3}. The extractant concentration was constant at 30% tributyl phosphate. The equilibrium experiments have produced data which demonstrate that thorium nitrate concentration, free acid, and density are related in equilibrium behavior between the aqueous and organic phases from 30 to 60{sup 0}C in the 30% tributyl phosphate-dodecane solvent extraction system. The concentration interactions apply to both the two- and three-phase regions. A linear correlation was observed for the density (D) of the aqueous or organic phase and the concentration of thorium and free acid. The general form of the equation is D = a(C/sub Th/ + bC/sub H/) + c, where a is the slope, b is the constant, c is the intercept, and C/sub Th/ and C/sub H/ are the molar concentrations of thorium and free acid respectively. The relationship of temperature, thorium nitrate, and free acid makes possible the definitions of the boundaries between the two- and three-phase regions. This dependence, in turn, permits operational control or simulation studies of the system within the two-phase region. The data demonstrate the interactions of the components of the Thorex system and can be used to improve the mathematical description of equilibrium in the SEPHIS-Thorex computer program

Predictors for Readmission up to 1 Year Following Hip Fracture

Background: At Altnagelvin, a district general hospital in Northern Ireland, we have observed that a significant number of hip fracture admissions are later readmitted for treatment of other medical conditions. These readmissions place increasing stress on the already significant burden that orthopedic trauma poses on national health services. Objectives: The aim of this study was to review a series of consecutive patients managed at our unit at least 1 year prior to the onset of the study. Also, we aimed to identify predictors for raised admission rates following treatment for hip fracture. Patients and Methods: We reviewed a prospective fracture database and online patient note system for patient details, past medical history, discharge destination and routine blood tests for any factors that may influence readmission rates up to 1 year. Data were analyzed using SPSS software. Results: Over 2 years, 451 patients were reviewed and 23 were managed conservatively. There was a 1-year readmission rate of 21%. Most readmission diagnoses were medical including bronchopneumonia, falls, urosepsis, cardiac exacerbations and stroke. Prolonged length of stay and discharge to a residential, fold or nursing home were found to increase readmission rate. Readmission diagnoses closely reflected the perioperative diagnoses that prolonged length of stay. Increased odds radio and risk of readmission were also found with female gender, surgery with a cephalomedullary nail, hip hemiarthroplasty or total hip replacement, time to surgery 2 g/dL and also if a blood transfusion was received. Conclusions: Our results indicate that hip fracture treatment begins at acute fracture clerk in, with consideration of comorbid status and ultimate discharge planning remaining significant predictors for morbidity and subsequent readmission

Vitamin D3 supplementation combined with sprint interval training improves aerobic and anaerobic exercise performance over sprint interval training alone in recreational combat sport athletes

Objectives: Correcting vitamin D deficiency might improve aerobic and anaerobic exercise performance. However, it is unclear if vitamin D 3 supplementation can convey a positive ergogenic benefit to aerobic and anaerobic exercise performance when combined with sprint interval training (SIT). Methods: Twenty-seven recreational male combat sport athletes were recruited (age: 25 ± 5 years, stature: 178 ± 7 cm, weight: 77 ± 10 kg). Participants completed baseline haematocrit and haemoglobin testing, lower body and upper body VO 2peak testing and two consecutive lower and upper body Wingate tests separated by five minutes rest. Participants were randomly assigned to either the vitamin D 3 group (VITD) or placebo group (CON) and underwent 6 weeks of twice-weekly SIT and weekly supplementation (50,000 IU.week −1). Following the intervention, testing was repeated. Results: Haemoglobin (P &lt; 0.001), haematocrit (P &lt; 0.001) and LB VO 2peak (P = 0.016) increased in VITD, remaining unchanged in CON (haemoglobin P = 0.981; haematocrit P = 0.947, LB VO 2peak P = 0.750). UB VO 2peak was unchanged in both groups (P = 0.284). LB and UB time to exhaustion increased in both groups (P &lt; 0.001). LB oxygen kinetics was not affected in either group (P = 0.063) with UB oxygen kinetics improved in VITD (P = 0.028). LB and UB Wingate peak power improved in both groups (P &lt; 0.001). LB Wingate average power improved in both groups (P &lt; 0.001) with VITD increasing average power over CON. Conclusion: Given the results, supplementing 50,000 IU of vitamin D 3 per week for six weeks combined with six weeks of SIT may improve markers of aerobic and anaerobic performance in recreational male combat sport athletes. </p

Investigating tiredness in Australian general practice - Do pathology tests help in diagnosis?

Copyright © 2003 Australian College of General Practitioners Copyright to Australian Family Physician. Reproduced with permission. Permission to reproduce must be sought from the publisher, The Royal Australian College of General Practitioners.INTRODUCTION: Tiredness is a common presentation in general practice for which pathology tests are commonly ordered. Our aim was to study their utilisation for tiredness. METHODS: We examined an integrated database which contains the medical records for 58,139 patients and their 696,518 associated general practitioner encounters. Three hundred and forty-two patients and their 1652 associated encounters were randomly selected out of 12,291 patients and their 26,748 associated encounters that had mentioned tiredness (or a synonym). RESULTS: One hundred and eighty-one patients (53%) had at least one pathology test ordered at any time in their episode of care. Patients over 60 years of age, patients who consulted their GP more than once and patients without comorbidity were more likely to have a pathology test ordered. Only 12 patients (3%) had a significant clinical diagnosis based on an abnormal pathology test. CONCLUSION: Pathology testing for patients presenting with tiredness is high. Most tests do not yield a significant clinical diagnosis.A Gialamas, JJ Beilby, NL Pratt, R Henning, JE Marley and JF Roddic