bluuebunny/crossref_metadata_2025_split huggingface dataset:
Volatile liquid hydrocarbons in waters of the Gulf of Mexico and Caribbean Sea1
Authors: Sauer Theodor C. 
Published: March 2010

Concentrations of volatile liquid hydrocarbons (VLH), C6−C14 hydrocarbons, were determined in 1977 in coastal, shelf, and open‐ocean surface waters of the Gulf of Mexico and Caribbean Sea. In open‐ocean, nonpetroleum‐polluted surface water, VLH concentrations were 60 ng·liter−1 while in heavily polluted Louisiana shelf and coastal water values reached ≈500 ng·liter−1. Caribbean surface samples had very low concentrations, ≈30 ng·liter−1. The relationship between anthropogenic gaseous hydrocarbons and VLH was approximately linear. Aromatic VLH accounted for 60–85% of the total VLH in surface waters. Cycloalkane concentrations were <1.0 ng·liter−1 in open ocean water, 60–100 ng·liter−1 in polluted water (20% of total VLH). Alkanes were ≈15 ng·liter−1 in open ocean water, 40 ng·liter−1 in polluted water. The concentrations of five major VLH compounds (aromatics) in water samples—benzenc, toluene, ethylbenzene, m‐, p‐xylenes, and o‐xylene (called BTX)— were sufficient to predict the total VLH. The empirically determined relationship is VLH(ng·liter−1) = 1.42 BTX (ng·liter−1); r = 0.96.Subsurface VLH concentrations in samples of polluted waters collected from depths of 50 in were only 35–40 ng·liter−1 below surface concentrations. Open ocean subsurface samples had concentrations of only ≈30 ng·liter−1 at 30–50‐m depths, comparable to those of Caribbean surface water.
Size‐selective predation, light transmission, and oxygen stratification: Evidence from the recent sediments of manipulated lakes1
Authors: Kitchell Jennifer A. , Kitchell James F. 
Published: March 2010

In an experiment maintained since 1951, half of a divided lake was limed, resulting in a significantly expanded euphotic zone. In both basins native fish were removed and rainbow trout introduced. Quantitative analysis of zooplankton remains preserved in the sediments of both lakes provides evidence of the selectivity of a visually dependent predator at natural and enhanced transparency and oxygen concentrations.The sediment record effectively documents the known manipulations and the expected responses. In the control lake, no significant changes in zooplankton species composition, species dominance, or size‐frequency distribution are recorded. In the alkalized lake, a succession in zooplankton dominance from Daphnia pulex to Daphnia rosea to Bosmina is recorded, as is a reciprocal change in mean size of D. pulex and D. rosea. The relative position of the thermocline with respect to the oxygen minimum barrier and the light transmission curve accounts for the observed differences in selective predation intensity.
The egg production of a marine planktonic copepod in relation to its food supply: Laboratory studies1
Authors: Checkley David M. 
Published: March 2010

Egg production by Paracalanus parvus, a particle‐grazing copepod, was investigated in relation to its food supply. The concentration of available food (P) and the rates of ingestion (I) and egg production (B) were measured simultaneously at intervals of 6 h to 2 d for periods of 2–10 d. Concentration, chemical composition (carbon and nitrogen), and species of phytoplankton were experimental variables.Egg production was related to the food ingested during the previous day. For one food type, I and B were rectilinear functions of P. The average maximum rates of ingestion and egg production were 1.1 µg N·female−1·d−1 and 53 eggs·female−1·d−1, equivalent to specific rates of 1.5 and 0.37·d−1. B was proportional to I below a critical ingestion rate, Ic, and independent of I above Ic. For I <Ic, the gross efficiency of egg production (B ·I−1) in terms of nitrogen was 0.37 while in terms of carbon it was a hyperbolic function of the ratio of C:N in the food, ranging between 0.41 (C:Nfood = 4.0) and 0.15 (C:Nfood = 11). For I >Ic, B·I−1 declined in terms of both carbon and nitrogen.These results, together with the ratio of C:N in particulate matter in the sea off southern California, suggest that nitrogen (hence protein) potentially limits egg production by adult female Paracalanus and that ingested carbon is used inefficiently.
Windpower time series above a temperate lake
Authors: Stauffer Robert E. 
Published: March 2010

A computer model of windpower flux was developed for Lake Mendota, Madison, Wisconsin, based on 3‐h wind speeds and estimates of above‐lake bulk Richardson number, and then was applied to the period 1 April–31 October (1966–1975). Fifteen years (1962–1976) of hourly records were also analyzed for Simcoe, Ontario (Lake Erie Basin).Expected power varies diurnally during all seasons, in phase with, or lagging slightly behind the solar cycle. The diel amplitude is about 46% of the expected daily mean. At both Simcoe and Madison, the expected daily power above an ice‐free lake attains a broad maximum of 12–14 × 105 ergs·cm−2·d−1 in winter and early spring, drops sharply in late April, and shows a broad summer minimum of 3–4 × 105 ergs·cm−2·d−1 during July–August. The autocorrelation functions for both spring windpower and daily insolation show evidences of periodicity of about 7 days, probably related to synoptic‐scale cold front passages. Following the front, with its characteristic wind directional shift from SSW to NNW, a characteristic calm develops accompanied by intense solar radiation.The spring power histogram features a median value about half of the mean, because of the high probability of observing very low windpower coupled with a very long tail on the frequency distribution. Low power also shows a strong clustering tendency in spring, because of both the strong inversion conditions in that season and the period of about 7 days in the synoptic‐scale weather shifts.
Carbon budget of a marine phytoplankton‐herbivore system with carbon‐14 as a tracer1
Authors: Copping Andrea E. , Lorenzen Carl J. 
Published: March 2010

Adult female and stage V Calanus pacificus were fed 14C‐labeled phytoplankton in the laboratory in the form of monospecific cultures and natural populations. A carbon budget was constructed by following the 14C activity and the specific activity, over 48 h, in the phytoplankton, copepod, dissolved organic, dissolved inorganic, and fecal carbon compartments.The average incorporation of carbon into the copepod’s body was 45% of the phytoplankton carbon available. Of the phytoplankton carbon, 27% appeared as dissolved organic carbon, 24% as dissolved inorganic carbon, and 3–4% in the form of fecal pellets. All of the tracer was recovered at the end of the experiments. The specific activity of the phytoplankton compartment was constant throughout each experiment. The other compartments had initial specific activities of zero, or close to zero, and increased throughout the experiment. In most experiments, the copepod specific activity equalled that of the phytoplankton at the end of 48 h, while the dissolved organic carbon, dissolved inorganic carbon, and fecal specific activities remained well below that of the phytoplankton.
Food limitation of egg production by a marine, planktonic copepod in the sea off southern California1
Authors: Checkley David M. 
Published: March 2010

The in situ rate of egg production (B) and female size of Paracalanus parvus, a particle‐grazing copepod, water temperature, and the concentrations of chlorophyll a and particulate nitrogen were measured in 31 collections from the euphotic zone of the sea off southern California. B was correlated positively with chlorophyll a and female size and negatively with temperature. A multiple regression of log B on chlorophyll a, particulate nitrogen, female size, and temperature accounts for 44% of the variation in log B.B was predicted best by an empirical function of food concentration when the food available in nature was considered to be phytoplankton rather than of all types of particulate matter >5 µ.An index of immediate food limitation was derived from laboratory data as a function of food concentration. When applied to extensive measurements of chlorophyll a in the euphotic zone, this index indicates that Paracalanus was often food limited and that food limitation increased along an onshore‐offshore transect. Paracalanus was rarely food limited in Santa Monica Bay.
Dimethylsulfoxide in marine and freshwaters
Authors: Andreae Meinart O. 
Published: March 2010

Dimethylsulfoxide (DMSO) occurs at concentrations of >10 nmol·liter−1 in the surface ocean and in rivers and lakes, and is not detected (<1 nmol·liter below the euphotic zone. Its concentration correlates well with indicators of primary productivity and with dimethylarsinate, an algal excretion product. Seven of eight pure, axenic cultures of marine planktonic algae produced significant amounts of DMSO. These findings suggest that DMSO is associated with phytoplankton activity in surface waters.DMSO occurs in rain ( ≈5 nmol·liter−1) from marine air masses, suggesting that DMSO, dimethylsulfide, or both participate in the transfer of sulfur between ocean and atmosphere.
Validation of manual muscle testing and a subset of eight muscles for adult and juvenile idiopathic inflammatory myopathies
Authors: Rider Lisa G. , Koziol Deloris , Giannini Edward H. , Jain Minal S. , Smith Michaele R. , Whitney‐Mahoney Kristi , Feldman Brian M. , Wright Susan J. , Lindsley Carol B. , Pachman Lauren M. , Villalba Maria L. , Lovell Daniel J. , Bowyer Suzanne L. , Plotz Paul H. , Miller Frederick W. , Hicks Jeanne E. 
Published: March 2010

AbstractObjectiveTo validate manual muscle testing (MMT) for strength assessment in juvenile and adult dermatomyositis (DM) and polymyositis (PM).MethodsPatients with PM/DM (73 children and 45 adults) were assessed at baseline and reevaluated 6–9 months later. We compared Total MMT (a group of 24 proximal, distal, and axial muscles) and Proximal MMT (7 proximal muscle groups) tested bilaterally on a 0–10 scale with 144 subsets of 6 and 96 subsets of 8 muscle groups tested unilaterally. Expert consensus was used to rank the best abbreviated MMT subsets for face validity and ease of assessment.ResultsThe Total, Proximal, and best MMT subsets had excellent internal reliability (Total MMT rs = 0.91–0.98), and consistency (Cronbach's α = 0.78–0.97). Inter‐ and intrarater reliability were acceptable (Kendall's W 0.68–0.76, rs = 0.84–0.95). MMT subset scores correlated highly with Total and Proximal MMT scores and with the Childhood Myositis Assessment Scale, and correlated moderately with physician global activity, functional disability, magnetic resonance imaging, and axial and distal MMT scores, and, in adults, with creatine kinase level. The standardized response mean for Total MMT was 0.56 in juveniles and 0.75 in adults. Consensus was reached to use a subset of 8 muscles (neck flexors, deltoids, biceps, wrist extensors, gluteus maximus and medius, quadriceps, and ankle dorsiflexors) that performed as well as the Total and Proximal MMT, and had good face validity and ease of assessment.ConclusionThese findings aid in standardizing the use of MMT for assessing strength as an outcome measure for myositis.
Risk of revision for infection in primary total hip and knee arthroplasty in patients with rheumatoid arthritis compared with osteoarthritis: A prospective, population‐based study on 108,786 hip and knee joint arthroplasties from the Norwegian Arthroplasty Register
Authors: Schrama Johannes C. , Espehaug Birgitte , Hallan Geir , Engesæter Lars B. , Furnes Ove , Havelin Leif I. , Fevang Bjorg‐Tilde S. 
Published: March 2010

AbstractObjectiveTo compare differences in the risk of revision for infection and changes in risk over time and in time from primary surgery to revision for infection after total hip replacement (THR) and total knee replacement (TKR) in rheumatoid arthritis (RA) and osteoarthritis (OA) patients.MethodsIn the Norwegian Arthroplasty Register, 6,629 and 102,157 primary total joint replacements in patients with RA and OA, respectively, were identified from 1987 (1994 for knees) until 2008. Survival analyses with revision due to infection as the end point were performed using Kaplan‐Meier methods for constructing survival curves and multiple Cox regression to calculate relative risk (RR) estimates for diagnosis, age, sex, and year of primary surgery. An extended Cox model was used to estimate RR within different followup intervals.ResultsRA patients with TKR had a 1.6 times higher risk of revision for infection than OA patients, whereas there was no difference in the THRs. In the THRs, we found a higher risk of revision for infection from 2001 onward, whereas the development for TKRs was the opposite. These time effects affected the RA and OA groups equally. The risk of revision for infection from 6 years postoperatively on was higher in RA patients.ConclusionThe overall risk of revision for infection after TKR was higher in RA patients. The risk of late infection leading to revision of the TKR and THR was higher in RA patients than in OA patients. After the year 2000, the RR of revision for infection in RA compared with OA remained unchanged.
Prevalence of specific types of arthritis and other rheumatic conditions in the ambulatory health care system in the United States, 2001–2005
Authors: Sacks Jeffrey J. , Luo Yao‐Hua , Helmick Charles G. 
Published: March 2010

AbstractObjectiveTo estimate the overall prevalence of medically‐treated arthritis and other rheumatic conditions (AORC) for adults, the prevalence of specific medically‐treated conditions, and the overall annual number of visits for these conditions in the ambulatory health care system.MethodsWe used data from the 2001–2005 National Ambulatory Medical Care Survey and 2001–2005 National Hospital Ambulatory Medical Care Survey to estimate annual ambulatory health care visits for the International Classification of Diseases, Ninth Revision, Clinical Modification codes thought to represent AORC. Using data on the number of prior annual visits per patient per condition, we converted the visit estimates into prevalence estimates of adults age ≥18 years with medically‐treated AORC overall and for specific conditions.ResultsThe overall prevalence estimate of adults with medically‐treated AORC was 29,150,000 adults (95% confidence interval [95% CI] 26,473,000–31,826,000) and accounted for 77,887,300 ambulatory care visits (95% CI 71,266,000–84,508,000). The top 5 most prevalent conditions were osteoarthritis and allied disorders, unspecified joint disorders, peripheral enthesopathies, unspecified arthropathies, and other disorders of synovium, tendon, or bursa.ConclusionThe advantage of our approach is that it uses existing rather than expensive new surveys for tracking the prevalence of medically‐treated AORC overall and tracking the prevalence of difficult to measure specific conditions. The estimates are data based and national in scope. More relevantly, they better estimate the numbers of persons whose AORC impacts on the ambulatory health care system.
Predictors of single‐leg standing balance in individuals with medial knee osteoarthritis
Authors: Hunt Michael A. , McManus Fiona J. , Hinman Rana S. , Bennell Kim L. 
Published: March 2010

AbstractObjectiveTo identify factors related to single‐leg standing balance in individuals with medial compartment knee osteoarthritis (OA).MethodsThis cross‐sectional study assessed clinical, demographic, and biomechanical measures in 57 individuals and their relationships with single‐leg standing balance. Differences in age, mass, symptoms, knee pain, radiographic severity, lower extremity alignment, and hip and knee extension as well as hip abduction torques were compared between those who could and could not perform 3 trials of single‐leg standing balance. Multiple regression was used to identify predictors of center of pressure (COP) path length in those who could complete the task.ResultsThirty‐four individuals (60%) successfully completed all 3 single‐leg standing balance trials and were significantly younger (P = 0.003) than those who could not. No other variable was significantly different between the groups. Disease severity, number of painful knees, lower extremity alignment, pain intensity, and quadriceps torque were all significant predictors of COP path length. Specifically, better single‐leg standing balance (smaller COP path length) was related to more severe radiographic changes and stronger quadriceps, those with bilateral symptoms, and to less varus malalignment and knee pain.ConclusionSingle‐leg standing balance in those with medial knee OA is related to the modifiable factors lower extremity alignment, knee pain, and quadriceps strength. Given the reduced balancing ability in this patient population, interventions targeting these factors are necessary.
Self‐reported knee and foot alignments in early adult life and risk of osteoarthritis
Authors: McWilliams Daniel F. , Doherty Sally , Maciewicz Rose A. , Muir Kenneth R. , Zhang Weiya , Doherty Michael 
Published: March 2010

AbstractObjectiveTo determine whether self‐reported early adult life malalignment of knees or feet are risk factors for knee or hip osteoarthritis (OA).MethodsParticipants in the Genetics of Osteoarthritis and Lifestyle case–control database were sent a questionnaire (n = 3,022) containing line‐drawing instruments for self‐reported knee and foot alignment at ages 20–29 years. Respondents were categorized as having straight, valgus, or varus knee, and straight, toe‐in, or toe‐out feet. Radiographic criteria were used to define current isolated knee or hip OA, combined knee and hip OA, or non‐OA controls. Odds ratios (ORs), adjusted ORs, and 95% confidence intervals (95% CIs) were calculated and logistic regression was performed.ResultsThe response rate was 72%; 87.5% of responders (n = 1,901) completed the alignment questions. Increased risk of isolated knee OA occurred with early adult varus (adjusted OR 5.16, 95% CI 2.87–9.41) and valgus knees (adjusted OR 3.16, 95% CI 1.04–9.64). The positive association between knee OA and toe‐in foot was explained by varus knee. There was an increased risk of combined knee/hip OA from varus (adjusted OR 4.52, 95% CI 2.39–8.53) and valgus knees (adjusted OR 3.07, 95% CI 0.99–9.54). Varus knee was associated with risk of medial tibiofemoral OA, whereas valgus knee was associated with risk of lateral tibiofemoral and lateral patellofemoral OA. Toe‐out foot was associated with reduced medial patellofemoral OA. For knee OA, a multiplicative interaction analysis between occupational risks and varus/valgus yielded an ORint of 3.20 (95% CI 1.08–9.49).ConclusionConstitutional alignment of the leg in terms of varus or valgus knee or foot rotation may be a significant factor in determining development and distribution of knee but not hip OA.
Accurate detection of changes in disease activity in primary Sjögren's syndrome by the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index
Authors: Seror Raphaèle , Mariette Xavier , Bowman Simon , Baron Gabriel , Gottenberg Jacques Eric , Boostma Hendrika , Theander Elke , Tzioufas Athanasios , Vitali Claudio , Ravaud Philippe ,   European League Against Rheumatism Sjögren's Task Force
Published: March 2010

AbstractObjectiveTo assess and compare the sensitivity to change of the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (ESSDAI) with that of other primary Sjögren's syndrome (SS) disease activity indexes.MethodsWe abstracted 96 patient profiles, including data on 3 successive visits (visits 1–3), from the medical charts of patients with primary SS. Patient profiles were scored with the ESSDAI, SS Disease Activity Index (SSDAI), and Sjögren's Systemic Clinical Activity Index (SCAI). Thirty‐nine experts assessed 5 profiles for whether disease activity had improved, worsened, or remained stable at visits 2 and 3.ResultsFor improved patients, the standardized response means (SRMs) for all scores did not differ, and ranged from −1.08 to −1.38 between visits 1 and 2 and from −0.50 to −0.76 between visits 2 and 3. For patients with worsened activity, the SRMs between visits 1 and 2 and between visits 2 and 3 were +0.46 and +1.10 for the ESSDAI, −0.03 and +0.79 for the SSDAI, and +0.17 and +1.02 for the SCAI, respectively. For patients with stable activity, the SRMs between visits 1 and 2 and between visits 2 and 3 were 0.00 and −0.13 for the ESSDAI, −0.44 and −0.11 for the SSDAI, and −0.36 and +0.34 for the SCAI, respectively.ConclusionFor patients with improved activity, the 3 disease activity indexes showed similar, large sensitivity to change. However, the ESSDAI seemed to detect changes in activity more accurately than other disease activity indexes. Notably, for patients with stable activity, the ESSDAI did not show erroneous improvement.
Development and initial validation of a self‐assessed lupus organ damage instrument
Authors: Costenbader Karen H. , Khamashta Munther , Ruiz‐Garcia Silvia , Perez‐Rodriguez Maria Teresa , Petri Michelle , Elliott Jennifer , Manzi Susan , Karlson Elizabeth W. , Turner‐Stokes Tabitha , Bermas Bonnie , Coblyn Jonathan , Massarotti Elena , Schur Peter , Fraser Patricia , Navarro Iris , Hanly John G. , Shaver Timothy S. , Katz Robert S. , Chakravarty Eliza , Fortin Paul R. , Sanchez Martha L. , Liu Jigna , Michaud Kaleb , Alarcón Graciela S. , Wolfe Frederick 
Published: March 2010

AbstractObjectiveThe Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) is a validated instrument for assessing organ damage in systemic lupus erythematosus (SLE). Trained physicians must complete it, thus limiting utility where this is impossible.MethodsWe developed and pilot tested a self‐assessed organ damage instrument, the Lupus Damage Index Questionnaire (LDIQ), in 37 SLE subjects and 7 physicians. After refinement, 569 English‐speaking SLE subjects and 14 rheumatologists from 11 international SLE clinics participated in validation. Subjects and physicians completed the instruments separately. We calculated sensitivity, specificity, Spearman's correlations, and agreement using the SDI as the gold standard. Six hundred five SLE participants in the community‐based National Data Bank for Rheumatic Diseases (NDB) study completed the LDIQ and we assessed correlations with outcome and disability measures.ResultsThe mean LDIQ score was 3.3 (range 0–16) and the mean SDI score was 1.5 (range 0–9). The LDIQ had a moderately high correlation with the SDI (Spearman's r = 0.50, P < 0.001). Specificities of individual LDIQ items were >80%, except for neuropathy. Sensitivities were variable and lowest for damage, with <1% prevalence. Agreement between the SDI and LDIQ was >85% for all but neuropathy, reduced renal function, deforming arthritis, and alopecia. In the NDB, the LDIQ correlated well with the comorbidity index (r = 0.45), the Short Form 36 physical component scale (r = 0.43), the Medical Research Council dyspnea scale (r = 0.40), disability (r = 0.37), and the Systemic Lupus Erythematosus Activity Questionnaire score (r = 0.37).ConclusionThe metric properties of the LDIQ are good compared with the SDI. It has construct validity and correlations with health assessments similar to the SDI. The LDIQ should allow expansion of SLE research. Its ultimate value will be determined in longitudinal studies.