bluuebunny/crossref_metadata_2025 huggingface dataset:
A contrail cirrus prediction model
Authors: Schumann U.
Published: May 2012

Abstract. A new model to simulate and predict the properties of a large ensemble of contrails as a function of given air traffic and meteorology is described. The model is designed for approximate prediction of contrail cirrus cover and analysis of contrail climate impact, e.g. within aviation system optimization processes. The model simulates the full contrail life-cycle. Contrail segments form between waypoints of individual aircraft tracks in sufficiently cold and humid air masses. The initial contrail properties depend on the aircraft. The advection and evolution of the contrails is followed with a Lagrangian Gaussian plume model. Mixing and bulk cloud processes are treated quasi analytically or with an effective numerical scheme. Contrails disappear when the bulk ice content is sublimating or precipitating. The model has been implemented in a "Contrail Cirrus Prediction Tool" (CoCiP). This paper describes the model assumptions, the equations for individual contrails, and the analysis-method for contrail-cirrus cover derived from the optical depth of the ensemble of contrails and background cirrus. The model has been applied for a case study and compared to the results of other models and in-situ contrail measurements. The simple model reproduces a considerable part of observed contrail properties. Mid-aged contrails provide the largest contributions to the product of optical depth and contrail width, important for climate impact.
Importance of the surface size distribution of erodible material: an improvement on the Dust Entrainment And Deposition (DEAD) Model
Authors: Mokhtari M. , Gomes L. , Tulet P. , Rezoug T.
Published: May 2012

Abstract. This paper is based on dust aerosol cycle modelling in the atmospheric model ALADIN (Aire Limitée Adaptation dynamique Développement InterNational) coupled with the EXternalised SURFace scheme SURFEX. Its main goal is to create an appropriate mineral dust emission parameterization compatible with the global database of land surface parameters ECOCLIMAP, and the Food and Agriculture Organization (FAO) soil type database in SURFEX. An improvement on the Dust Entrainment And Deposition scheme (DEAD) is proposed in this paper by introducing the geographical variation of surface soil size distribution, the Marticorena and Bergametti (1995) formulation of horizontal saltation flux and the Shao et al. (1996) formulation of sandblasting efficiency α. To show the importance of the modifications introduced in the DEAD, both sensitivity and comparative studies are conducted in 0 dimensions (0-D) and then in 3 dimensions (3-D) between the old DEAD and the new DEAD. The results of the 0-D simulations indicate that the revised DEAD scheme represents the dust source emission better, particularly in the Bodélé depression, and provides a reasonable friction threshold velocity. In 3-D simulations, small differences are found between the DEAD and the revised DEAD for the simulated Aerosol Optical Depth (AOD) compared with the AErosol RObotic NETwork (AERONET) photometer measurements available in the African Monsoon Multidisciplinary Analyses (AMMA) databases. For the surface concentration, a remarkable improvement is noted for the revised DEAD scheme.
Laminar and weakly turbulent oceanic gravity currents performing inertial oscillations
Authors: Wirth A.
Published: May 2012

Abstract. The small scale dynamics of a weakly turbulent oceanic gravity current is determined. The gravity current considered is initially at rest and adjusts by performing inertial oscillations to a geostrophic mean flow. The dynamics is explored with a hierarchy of mathematical models. The most involved are the fully 3-D Navier-Stokes equations subject to the Boussinesq approximation. A 1-D and 0-D mathematical model of the same gravity current dynamics are systematically derived. Using this hierarchy and the numerical solutions of the mathematical models, the turbulent dynamics at the bottom and the interface is explored and their interaction investigated. Three different regimes of the small scale dynamics of the gravity current are identified, they are characterised by laminar flow, coherent roll vortices and turbulent dynamics with coherent streaks and bursts. The problem of the rectification of the turbulent fluxes, that is, how to average out the fluctuations and calculate their average influence on the flow, is considered. It is shown that two different regimes of friction are superposed, an Ekman friction applies to the average geostrophic flow and a linear friction, not influenced by rotation, to the inertial oscillations. The combination of the two makes the bulk friction non-local in time for the 0-D model. The implications of the results for parametrisations of the Ekman dynamics and the small scale turbulent fluxes in the planetary boundary layer are discussed.
Drifting snow climate of the Greenland ice sheet: a study with a regional climate model
Authors: Lenaerts J. T. M. , van den Broeke M. R. , van Angelen J. H. , van Meijgaard E. , Déry S. J.
Published: May 2012

Abstract. This paper presents the drifting snow climate of the Greenland ice sheet, using output from a high-resolution (~11 km) regional climate model (RACMO2). Because reliable direct observations of drifting snow do not exist, we evaluate the modeled near-surface climate instead, using Automatic Weather Station (AWS) observations from the K-transect and find that RACMO2 realistically simulates near-surface wind speed and relative humidity, two variables that are important for drifting snow. Integrated over the ice sheet, drifting snow sublimation (SUds) equals 24 ± 3 Gt yr−1, and is significantly larger than surface sublimation (SUs, 16 ± 2 Gt yr−1). SUds strongly varies between seasons, and is only important in winter, when surface sublimation and runoff are small. A rapid transition exists between the winter season, when snowfall and SUds are important, and the summer season, when snowmelt is significant, which increases surface snow density and thereby limits drifting snow processes. Drifting snow erosion (ERds) is only important on a regional scale. In recent decades, following decreasing wind speed and rising near-surface temperatures, SUds exhibits a negative trend (0.1 ± 0.1 Gt yr−1), which is compensated by an increase in SUs of similar magnitude.
Socio-Cultural and Economic Impediments of Inequality in Provision of Educational Right to Female: A Case of Southern Punjab (Pakistan)
Authors: Sattar Tehmina , Yasin Ghulam , Afzal Saima
Published: May 2012

Abstract:Inequality in provision of educational right to girls is the leading rationale of their exclusion from the mainstream. If the marginalized sections of the society such as minorities, disabled and girls are given education as their indispensable human right then this will escorts towards their social inclusion in education sector. Enrollment ratios of girls lag far behind than boys at all levels of education in Pakistan. Worldwide literacy rates for adult men far exceed from women. Education enhances labor market productivity and income growth, yet educated women have beneficial effects on social well-being of the family. The social benefits from women's education ranges from fostering economic growth to extending the average life expectancy among female population. Despite these facts the issue of educational right for girls has been denied in the educational policies of Pakistan since 1947. In Pakistan women have to face biasness in acquiring quality education. Gender discrimination is explicit from Economic Survey of Pakistan (2010) where the men are 65% literate and the women are 45% literate. In Southern Punjab (Pakistan) rigid cultural patterns, poverty, prejudice, stereotypic expectations from girls education, restricted movement of girls, precarious traveling and lack of female teachers confines the girls from acquiring quality education. The respondents (N=600) were interviewed from affiliated schools (n=100 out of N=520) from BISE through multistage sampling technique from Multan and Khanewal districts. The results of the research illustrated that parental preference to boys education, rigid cultural patterns, cost of schooling (direct and indirect) and low socio-economic status of the parents were the foremost determinants of social exclusion of girls from education sector of Southern Punjab (Pakistan). Despite these determinants family size, prejudice, patriarchal structure of society, limited involvement of girls in decision making process and rigid values allied with girls education are the major constraints that restricted the access of girls from education sector of Southern Punjab (Pakistan).
Retinal Nerve Fiber Layer Thickness Variability in Leber Hereditary Optic Neuropathy Carriers
Authors: Barboni Piero , Savini Giacomo , Feuer William J. , Budenz Donald L. , Carbonelli Michele , Chicani Filipe , Ramos Carolina Do V.F. , Salomao Solange R. , De Negri Annamaria , Parisi Vincenzo , Carelli Valerio , Sadun Alfredo A.
Published: May 2012

Purpose.

Recent investigations suggested that unaffected carriers of Leber hereditary optic neuropathy (LHON) may show subclinical visual alterations. Structural changes have also been detected by optical coherence tomography (OCT), which revealed a temporal thickening of the retinal nerve fiber layer (RNFL). These changes may reflect compensatory effects such as mitochondria accumulation within the RNFL axons. This study aimed to investigate whether the RNFL of LHON carriers shows greater than expected thickness variations, which may reflect transient subclinical changes, over the course of years.

Methods.

Using Stratus OCT, the RNFL thickness was measured yearly from 2005 to 2008 in 24 Brazilian LHON carriers, all with homoplasmic 11778/ND4 mtDNA mutation. An Italian sample of 20 healthy subjects served as a control. Data were compared also to a previously published sample (n=59) of glaucomatous eyes.

Results.

The LHON carriers showed test-retest standard deviations that were larger than normal controls in the temporal (p=0.004), superior (p<0.0001), and inferior quadrants (p=0.019). Compared to the glaucoma cases, no statistical differences were observed.

Conclusions.

The RNFL thickness in LHON carriers, when measured at different time points, has higher variability than in normal subjects. Transitory RNFL swelling may be caused either by compensatory mechanisms (increased mitochondrial biogenesis) or by axonal stasis preceding decompensation of retinal ganglion cells. In both situations, these changes may represent the origin of the visual alterations previously detected in LHON carriers. Alternatively, increased variability of RNFL thickness may be influenced by the LHON microangiopathy, as retinal blood vessels contribute to the OCT RNFL thickness measurements.
Surgical Intervention in Central Toxic Keratopathy
Authors: Tu Kyaw L. , Aslanides Ioannis M.
Published: May 2012

Purpose.

To report management and outcome of 3 cases of bilateral central toxic keratopathy (CTK).

Methods.

A retrospective chart review on 3 laser-assisted in situ keratomileusis patients who developed CTK within a short time of one another.

Results.

Patient A had flap lifts and irrigation (FL+I) twice in the right eye (OD) on postoperative day 1 at diffuse lamellar keratitis (DLK) stage 3 and once each on days 1 (at DLK stage 3) and 5 (at CTK) for the left eye (OS). She attained 20/20 unaided visual acuity (UVA) OD at 1 month. Her UVA OS remained at 20/32 but best-corrected visual acuity (BCVA) gradually improved to 20/25 at 8 months. Patient B had right FL+I on day 3 and left FL+I on day 5 (both for CTK). His OS achieved full visual potential (20/25 UVA) by 1 month but UVA OD was reduced to 20/25 (preoperative BCVA 20/20) at 8 months. Patient C had medical management only. Her preoperative BCVA OD of 20/33 fell to 20/50 postoperative UCVA/BCVA; OS regained full visual potential of 20/40 between 2 and 8 months. Patient A's OD did not develop a full-blown CTK; instead an arrested CTK resulted. All except that one eye had initial hyperopic/astigmatic errors that gradually lessened. Artemis II imaging confirmed early stromal loss posterior to the flap with stroma regaining some thickness over the following months.

Conclusions.

Surgical intervention in cases of CTK may improve clinical outcomes.
Association of C‐reactive protein with high disease activity in systemic sclerosis: Results from the Canadian Scleroderma Research Group
Authors: Muangchan Chayawee , Harding Sarah , Khimdas Sarit , Bonner Ashley ,   Canadian Scleroderma Research Group, Baron Murray , Pope Janet
Published: May 2012

Objective

This study was performed to determine the prevalence of elevated C‐reactive protein (CRP) levels and the significance of CRP in clinical parameters in systemic sclerosis (SSc; scleroderma) patients.

Methods

Canadian Scleroderma Research Group data were used. Statistical comparisons were made for CRP levels ≤8 mg/liter versus >8 mg/liter, early (≤3 years from first non–Raynaud's phenomenon symptom) versus late SSc, and diffuse cutaneous SSc (dcSSc) versus limited cutaneous SSc (lcSSc). A survival analysis was analyzed between patients with normal versus elevated CRP levels.

Results

A total of 1,043 patients (mean ± SD age 55.4 ± 12.1 years, mean ± SD disease duration of 11.0 ± 9.5 years) were analyzed; elevation of CRP level and erythrocyte sedimentation rate (ESR; >20 mm/hour) occurred in 25.7% and 38.2%, respectively. Mean ± SD baseline CRP level in dcSSc (11.98 ± 25.41 mg/liter) was higher than in lcSSc (8.15 ± 16.09 mg/liter; P = 0.016). SSc patients with an early disease duration had a higher mean ± SD CRP level (12.89 ± 28.13 mg/liter) than those with a late disease duration (8.60 ± 17.06 mg/liter; P = 0.041). Although not consistent in all subsets, CRP was significantly associated (P < 0.01) with ESR, modified Rodnan skin score (MRSS), worse pulmonary function parameters, disease activity, damage, and Health Assessment Questionnaire. CRP level seemed to normalize in many SSc patients over time. Total lung capacity <80% predicted, MRSS, and serum creatinine were predictors of elevated CRP levels in SSc (odds ratio [OR] 2.76 [95% confidence interval (95% CI) 1.73–4.40], P = 0.0001; OR 1.03 [95% CI 1.01–1.05], P = 0.005; and OR 1.005 [95% CI 1.001–1.010], P = 0.02, respectively). Survival for patients with elevated CRP levels was less than for patients with normal CRP levels (P = 0.001).

Conclusion

CRP level is elevated in one‐quarter of SSc patients, especially early disease. It is correlated with disease activity, severity, poor pulmonary function, and shorter survival.
Cartilage thickening in early radiographic knee osteoarthritis: A within‐person, between‐knee comparison
Authors: Cotofana Sebastian , Buck Robert , Wirth Wolfgang , Roemer Frank , Duryea Jeff , Nevitt Michael , Eckstein Felix ,   Osteoarthritis Initiative Investigators Group
Published: May 2012

Objective

To determine whether the presence of definite osteophytes (in the absence of joint space narrowing [JSN]) on radiographs is associated with (subregional) increases in cartilage thickness in a within‐person, between‐knee cross‐sectional comparison of participants in the Osteoarthritis Initiative. Based on previous results, the external weight‐bearing medial femoral condyle (ecMF) and external weight‐bearing lateral femoral condyle (ecLF) subregions were selected as primary end points.

Methods

Both knees of 61 Osteoarthritis Initiative participants (n = 4,796) displayed definite tibial or femoral marginal osteophytes and no JSN in 1 knee, and no signs of radiographic osteoarthritis (OA) in the contralateral knee; this was confirmed by an expert central reader. In these participants, cartilage thickness was measured in 16 femorotibial subregions of each knee, based on sagittal double‐echo steady‐state with water excitation magnetic resonance images. Location‐specific joint space width from fixed‐flexion radiographs was determined using dedicated software. Location‐specific associations of osteophytes with cartilage thickness were evaluated using paired t‐tests and mixed‐effects models.

Results

Of the 61 participants, 48% had only medial osteophytes, 36% only lateral osteophytes, and 16% bicompartmental osteophytes. The knees with osteophytes had significantly thicker cartilage than contralateral knees without osteophytes in the ecMF (mean ± SD +71 ± 223 μmoles, equivalent to an increase of +5.5%; P = 0.015) and ecLF (mean ± SD +64 ± 195 μmoles, +4.1%; P = 0.013). No significant differences between knees were noted in other subregions or in joint space width. Cartilage thickness in the ecMF and ecLF was significantly associated with tibial osteophytes in the same (medial or lateral) compartment (P = 0.003).

Conclusion

The knees with early radiographic OA display thicker cartilage than (contralateral) knees without radiographic findings of OA, specifically in the external femoral subregions of compartments with marginal osteophytes.
Lumbar spine radiographic features and demographic, clinical, and radiographic knee, hip, and hand osteoarthritis
Authors: Goode Adam P. , Marshall Stephen W. , Renner Jordan B. , Carey Timothy S. , Kraus Virginia B. , Irwin Debra E. , Stürmer Til , Jordan Joanne M.
Published: May 2012

Objective

To determine the prevalence of lumbar spine individual radiographic features (IRFs) of disc space narrowing (DSN), osteophytes (OST), and facet joint osteoarthritis (FOA); to describe the frequencies of demographic, clinical, and radiographic knee, hip, and hand osteoarthritis (OA) across lumbar spine IRFs; and to determine factors associated with lumbar spine IRFs.

Methods

We conducted a cross‐sectional study of 840 participants enrolled in the Johnston County Osteoarthritis Project (2003–2004). Sample‐based prevalence estimates were generated for each lumbar spine IRF. The associations between lumbar spine IRFs and demographic, clinical, and peripheral joint OA were determined with logistic regression models.

Results

Sample‐based prevalence estimates were similar for DSN (57.6%) and FOA (57.9%) but higher for OST (88.1%), with significant differences across race and sex. Hand and knee OA frequencies increased across IRFs, whereas the effect was absent for hip OA. African Americans had lower odds of FOA (adjusted odds ratio [ORadj] 0.45 [95% confidence interval (95% CI) 0.32–0.62]), while there was no racial association with DSN and OST. Low back symptoms were associated with DSN (ORadj 1.37 [95% CI 1.04–1.80]) but not OST or FOA. Knee OA was associated with OST (ORadj 1.62 [95% CI 1.16–2.27]) and FOA (ORadj 1.69 [95% CI 1.15–2.49]) but not DSN. Hand OA was associated with FOA (ORadj 1.67 [95% CI 1.20–2.28]) but not with DSN or OST. No associations were found with hip OA.

Conclusion

These findings underscore the importance of analyzing lumbar spine IRFs separately as the associations with demographic, clinical, and radiographic knee, hip, and hand OA differ widely.
Incomplete reporting of recruitment information in clinical trials of biologic agents for the treatment of rheumatoid arthritis: A review
Authors: Simsek Ismail , Yazici Yusuf
Published: May 2012

Objective

It is important to evaluate how a randomized controlled trial (RCT) sample was assembled from the general patient population in order to determine whether a patient differs from those who participated in the trial in a meaningful way. The aim of this study is to assess the adequacy of reporting of the recruitment process of rheumatoid arthritis (RA) patients participating in RCTs with biologic agents.

Methods

We searched PubMed for all reports of RCTs involving etanercept, infliximab, adalimumab, golimumab, certolizumab, abatacept, tocilizumab, and rituximab in RA patients. Data recorded were eligibility fraction, enrollment fraction, recruitment fraction, and number of patients needed to be screened (NNS) in order to randomize 1 participant.

Results

Of the 66 trials included in the analysis, 23 (35%) reported the number of individuals assessed by investigators for eligibility, and 18 (27%) reported the number eligible for participation. Of the studies that reported quantitative recruitment information, the median eligibility fraction was 80.6% (interquartile range [IQR] 71.8–91.1%) and the median enrollment fraction was 100% (IQR 88.4–100%). The median NNS was found to be 1.28 (IQR 1.18–1.43).

Conclusion

A substantial majority of RCTs conducted in RA patients with biologic agents did not provide sufficient information about the patient recruitment process, which makes assessments of external validity difficult. The rate of reporting of the recruitment process in this study was found to be lower as compared to similar studies conducted in different specialties.
Association of morbid obesity with disability in early inflammatory polyarthritis: Results from the Norfolk Arthritis Register
Authors: Humphreys J. H. , Verstappen S. M. M. , Mirjafari H. , Bunn D. , Lunt M. , Bruce I. N. , Symmons D. P. M.
Published: May 2012

Objective

Obesity has been associated with disease outcomes in inflammatory arthritis. This study aimed to investigate cross‐sectionally the relationship between body mass index (BMI) and functional disability in a large inception cohort of patients with early inflammatory polyarthritis (IP).

Methods

Patients age ≥16 years with ≥2 swollen joints for ≥4 weeks were recruited into the Norfolk Arthritis Register. At the initial assessment, clinical and demographic data were obtained, joints were examined, and height and weight were measured. Blood samples were taken to measure inflammatory markers and autoantibodies, and patients completed the Health Assessment Questionnaire (HAQ) to assess functional disability. Univariate and multivariate ordinal regression were used to examine the cross‐sectional association between BMI and the HAQ. Multiple imputation using chained equations allowed inclusion of patients with missing variables.

Results

A total of 1,246 patients were studied (median age 57 years). Of those patients, 782 patients (63%) were female and 303 (25%) were obese (BMI ≥30 kg/m2). Morbid obesity (BMI ≥35 kg/m2) was significantly associated with worse functional disability in the univariate and multivariate analysis with missing data imputed, adjusting for age, sex, symptom duration, smoking status, disease activity, autoantibodies, comorbidities, and treatment (multivariate odds ratio 1.87, 95% confidence interval 1.14–3.07).

Conclusion

Morbid obesity in patients with early IP is associated with worse HAQ scores. This should be taken into account in patient management and when interpreting the HAQ in clinical practice.
Predictors of change in bodily pain in early rheumatoid arthritis: An inception cohort study
Authors: McWilliams Daniel F. , Zhang Weiya , Mansell Josephine S. , Kiely Patrick D. W. , Young Adam , Walsh David A.
Published: May 2012

Objective

To investigate possible predictors for lack of pain improvement after 1 year of treatment for early rheumatoid arthritis (RA).

Methods

The Early Rheumatoid Arthritis Network (ERAN) database was used for analysis of baseline and 1‐year pain data. The ERAN is a hospital‐based inception cohort of 1,189 people. Short Form 36 questionnaire bodily pain scores were used to calculate change in pain at 1 year as the outcome. The proportion of the Disease Activity Score in 28 joints (DAS28) attributable to patient‐reported components (joint tenderness and visual analog scale score; DAS28‐P) at baseline was derived as a predictor. Predictors of less improvement in pain were investigated using adjusted odds ratios (ORadj) generated by logistic regression, adjusting for 14 additional clinical and demographic covariates.

Results

Greater pain at baseline was associated with sex, high DAS28, worse mental health, and smoking. Most patients with early RA reported incomplete improvement in bodily pain after 1 year. The DAS28‐P index did not significantly change in the patients whose disease remained active. Less improvement in pain was predicted by female sex (ORadj 3.41, 95% confidence interval [95% CI] 1.35–8.64) and a high DAS28‐P index at baseline (ORadj for tertiles 2.09, 95% CI 1.24–3.55). Other conventional RA risk factors did not predict pain changes.

Conclusion

The factors most likely to predict less improvement in pain in early RA are female sex and a high DAS28‐P index. A high DAS28‐P index may reflect greater contributions of noninflammatory factors, such as central sensitization, to pain. Strategies in addition to inflammatory disease suppression may be required to adequately treat pain.
Disease‐specific knowledge and clinical skills required by community‐based physiotherapists to co‐manage patients with rheumatoid arthritis
Authors: Briggs Andrew M. , Fary Robyn E. , Slater Helen , Bragge Peter , Chua Jason , Keen Helen I. , Chan Madelynn
Published: May 2012

Objective

While strong evidence supports the role of physiotherapy in the co‐management of patients with rheumatoid arthritis (RA), it remains unclear what constitutes the essential disease‐specific knowledge and clinical skills required by community‐based physiotherapists to effectively and safely deliver recommended care. This study aimed to identify essential disease‐specific knowledge and skills, link these with evidence from clinical guidelines, and broadly determine the professional development (PD) needs and confidence related to the management of RA among physiotherapists.

Methods

An international Delphi panel of rheumatologists, physiotherapists, and consumers (n = 27) identified essential disease‐specific knowledge and clinical skills over 3 rounds. Physiotherapy‐relevant recommendations from high‐quality, contemporary clinical guidelines were linked to Delphi responses. Finally, an e‐survey of PD needs among registered physiotherapists (n = 285) was undertaken.

Results

Overarching themes identified by the Delphi panel across the RA disease stages included the need for excellent communication, the importance of a multidisciplinary team and early referral, adoption of chronic disease management principles, and disease monitoring. Of the essential Delphi themes, 86.7% aligned with clinical guideline recommendations. Up to 77.5% of physiotherapists reported not being confident in managing patients with RA. Across the range of essential knowledge and skills themes, 45.1–93.5% and 71.1–95.2% of respondents, respectively, indicated they would benefit from or definitely need PD.

Conclusion

To effectively manage RA, community‐based physiotherapists require excellent communication skills and disease‐specific knowledge, including understanding the role of the multidisciplinary team and the principles of early referral, chronic disease management, and monitoring. Physiotherapists identified a need for PD to develop these skills.
Structural Characterization of Sputtered Fe70Pd30 Thin Films During Ex Situ and In Situ TEM Heating
Authors: Bechtold Christoph , Lotnyk Andriy , Erkartal Burak , Kienle Lorenz , Quandt Eckhard
Published: May 2012

Magnetic shape memory (MSM) thin films have been investigated for their use as actuators and sensors in micro‐electro‐mechanical systems (MEMS). Here, we report on the fabrication of polycrystalline Fe7Pd3 thin films by magnetron sputtering. Two‐dimensionally structured, freestanding films can be obtained by the use of different lift‐off techniques and optical lithography. The effect of different heat treatments is discussed. In situ transmission electron microscopy of the as deposited films up to 850 °C shows intermediate phases during heating. Significant changes in magnetic properties of the intermediate phases are observed in complementary investigations on ex situ annealed freestanding films.
CNTs in Optoelectronic Devices: New Structural and Photophysical Insights on Porphyrin‐DWCNTs Hybrid Materials
Authors: Aurisicchio Claudia , Marega Riccardo , Corvaglia Valentina , Mohanraj John , Delamare Romain , Vlad Dana Alina , Kusko Cristian , Dutu Constantin Augustin , Minoia Andrea , Deshayes Gaëlle , Coulembier Olivier , Melinte Sorin , Dubois Philippe , Lazzaroni Roberto , Armaroli Nicola , Bonifazi Davide
Published: May 2012

The preparation and physical characterization of diverse porphyrin‐derived double‐walled carbon nanotubes (DWCNTs) conjugates are described. A porphyrin molecule is covalently linked and physically adsorbed to COOH‐derived DWCNTs. The photophysical properties of all porphyrin‐CNTs derivatives are studied in solution and in polymeric matrices. Definitive experimental evidence for photoinduced electron and/or energy transfer processes involving the porphyrin chromophores and the CNT wall is not obtained, but solid‐state UV‐vis absorption profiles display electronic transitions fingerprinting J‐ and H‐ type aggregates, where porphyrin molecules intermolecularly interact “head‐to‐tail” and “face‐to‐face”, respectively. In parallel, molecular modeling based on force‐field simulations is performed to understand the structure of the porphyrin‐CNTs interface and the nature of the interactions between the porphyrins and the DWCNTs. Finally, multilayered‐type devices are fabricated with the aim of investigating the interaction of the porphyrin‐derived DWCNTs with poly(3‐hexylthiophene)‐pyrene matrices containing small amounts of 1‐[3‐(methoxycarbonyl)propyl]‐1‐phenyl‐[6.6]C61.
Crystal Growth of Calcium Carbonate in Hydrogels as a Model of Biomineralization
Authors: Asenath‐Smith Emily , Li Hanying , Keene Ellen C. , Seh Zhi Wei , Estroff Lara A.
Published: May 2012

In recent years, the prevalence of hydrogel‐like organic matrices in biomineralization has gained attention as a route to synthesizing a diverse range of crystalline structures. Here, examples of hydrogels in biological, as well as synthetic, bio‐inspired systems are discussed. Particular attention is given to understanding the physical versus chemical effects of a broad range of hydrogel matrices and their role in directing polymorph selectivity and morphological control in the calcium carbonate system. Finally, recent data regarding hydrogel‐matrix incorporation into the growing crystals is discussed and a mechanism for the formation of these single‐crystal composite materials is presented.
The Impact of Carrier Transport Confinement on the Energy Transfer Between InGaN/GaN Quantum‐Well Nanorods and Colloidal Nanocrystals
Authors: Jiang Bin , Zhang Chunfeng , Wang Xiaoyong , Park Min Joo , Kwak Joon Seop , Xu Jian , Zhang Huichao , Zhang Jiayu , Xue Fei , Xiao Min
Published: May 2012

The energy transfer (ET) between InGaN/GaN multiple‐quantum‐well (MQW) nanorods (NRs) and semiconductor nanocrystals (NCs) for efficient color conversion is studied. An exceptional contribution of carrier transport confinement to the ET mechanisms is observed in the proximal side‐wall coupling system, which consists of InGaN/GaN NRs and CdSe NCs. Under relatively low or high excitation, the ET rate shows different carrier‐density dependence, resulting from different electron‐hole configurations, i.e., bound excitons and free carriers. In the localized exciton regime, the ET rate decreases when increasing temperature from 20 K to 200 K. However, in the free‐carrier regime, the ET rate varies insignificantly in the same temperature range. The temperature dependence in this NR‐NC coupling system is different from that in the previously studied planar MQW‐NC coupling system. It is suggested that the carrier transport confinement in NRs is a major factor for these divergences. The highly efficient ET with efficiency up to 80% shows a promising potential of using such NR‐NC coupled structures for ET‐pumped, NC‐based, light‐emitting devices.
Short‐term secular variation in menarche and blood lead concentration in school girls in the copper basin of southwestern poland: 1995 and 2007
Authors: Sławińska Teresa , Ignasiak Zofia , Little Bertis B. , Malina Robert M.
Published: May 2012

Objectives:

To evaluate short‐term secular change in menarche and associations with blood lead level in Polish girls between 1995 and 2007.

Methods:

Menarcheal status of school girls 7–16 years from villages in southwestern Poland was surveyed in 1995, 2001, 2004, and 2007. Blood lead was sampled in 1995 and 2007. Median ages and variance statistics for menarche were estimated with probit analysis. Associations between blood lead level and menarcheal status in 1995 and 2007 were analyzed with logistic regression using blood lead level as an independent binary variable: 2.00–5.00 and ≥5.10 μg/dl.

Results:

Median ages at menarche declined slightly from 1995 (13.36 ± 0.06 years) to 2001 (13.20 ± 0.04 years), was stable in 2004 (13.20 ± 0.05 years), and declined to 2007 (12.81 ± 0.05 years). Blood lead levels declined from 6.57 ± 0.13 μg/dl in 1995 to 4.24 ± 0.14 μg/dl in 2007. With age, height, and BMI controlled, probability of attaining menarche was not associated with blood lead in 1995, but was decreased with increased blood lead in 2007 (OR 0.31, 95% CI 0.09–1.06, P = 0.057).

Conclusion:

Ages at menarche and blood lead levels declined between 1995 and 2007. Higher blood lead levels were not associated with menarche in 1995, suggesting that nutritional and health conditions and perhaps somewhat unstable social and economic conditions in the 1980s and early 1990s may have masked the influence of lead on sexual maturation. Elevated blood lead was associated with the probability of later menarche in 2007, although the association was of borderline (P = 0.06). Am. J. Hum. Biol., 2012. © 2012 Wiley Periodicals, Inc.
Assessing the influence of occupational and physical activity on the rate of degenerative change of the pubic symphysis in portuguese males from the 19th to 20th century
Authors: Campanacho Vanessa , Santos Ana Luísa , Cardoso Hugo F.V.
Published: May 2012

Among the many factors suggested as potential sources of variation in the rate of ageing of the pubic symphysis is occupational/physical activity, but this has yet to be demonstrated. This study's main goal is to determine whether occupational/physical activity influences the aging process in the pubic symphysis. We analyzed a sample of 161 males (18–96 years) from two Portuguese identified skeletal collections, where age‐related features were recorded in the pubic symphysis as absent/present. The sample was divided in two groups according to the occupation of the individuals (manual and non‐manual) and in two groups according to the femoral robusticity index (robust and gracile). The manual and robust groups represent individuals with more physically demanding occupations while the non‐manual and gracile groups represent less physically demanding occupations. The possible influence of occupational/physical activity on the rate of ageing was evaluated by comparing the transition age for each age‐related feature, between the two groups, using logistic regression. Only the ligamentous outgrowths on the ventral beveling showed a statistically significant younger age in the robust group, indicating a possible faster rate or early timing of change in the individuals with a more physically demanding activity compared with their gracile counterparts. Thus, these results do not provide significant support to the hypothesis that individuals with a greater demanding occupation or physical activity show greater pubic symphysis degeneration. Further testing of this hypothesis in other samples with individuals from known occupation is required. Am J Phys Anthropol 148:371–378, 2012. © 2012 Wiley Periodicals, Inc.
Multi‐isotopic analysis reveals individual mobility and diet at the early iron age monumental tumulus of magdalenenberg, germany
Authors: Oelze Vicky M. , Koch Julia K. , Kupke Katharina , Nehlich Olaf , Zäuner Steve , Wahl Joachim , Weise Stephan M. , Rieckhoff Sabine , Richards Michael P.
Published: May 2012

For the Early Iron Age western Hallstatt culture, which includes the site of Magdalenenberg in southwest Germany, it has been proposed that people were mobile and maintained far reaching social and trading networks throughout Europe. We tested this hypothesis by analyzing multiple isotopes (strontium, oxygen, sulfur, carbon, and nitrogen) of the preserved skeletons from the Magdalenenberg elite cemetery to determine diets and to look for evidence of mobility. The analysis of carbon, nitrogen, and sulfur isotope ratios in collagen of humans (n = 50) and associated domestic fauna (n = 10) indicates a terrestrial‐based diet. There was a heterogeneous range of isotope values in both strontium (0.70725 to 0.71923, n = 76) and oxygen (13.4‰ to 18.5‰, n = 78) measured in tooth enamel. Although many of the individuals had values consistent with being from Hallstatt culture sites within southwest Germany, some individuals likely originated from further afield. Possible areas include the Alps of Switzerland and Austria or even locations in Italy. Our study strongly supports the assumption of far reaching social and economic networks in the western Hallstatt culture. Am J Phys Anthropol 148:406–421, 2012. © 2012 Wiley Periodicals, Inc.
Low birth weight does not predict the ontogeny of relative leg length of infants and children: An allometric analysis of the NHANES III sample
Authors: Bogin Barry , Baker Jack
Published: May 2012

Previous research links both low birth weight (LBW) and relative leg length (RLL) to a similar set of adult pathologies, including type II diabetes, coronary vascular disease, and some cancers. Historically, LBW has been frequently used as a broad indicator of the quality of the intrauterine environment, while RLL has been considered a sensitive measure of childhood environmental quality. While these observations have been taken to suggest that these measures reflect independent exposures at different life‐stages, their mutual association with a similar set of later pathologies makes this assumption less certain than it may have previously seemed. Nationally representative data from the Third National Health and Nutrition Examination Survey (NHANES III) are used to test the hypothesis that LBW predicts reductions in the development of leg length relative to stature. After controls for important socioeconomic exposures that might confound measurement of such a relationship, we find statistical and biological evidence that variation in birth weight and variation in the development of leg length relative to stature (RLL) are independent. The results suggest that these two measures may represent independent information on prenatal and postnatal environmental quality. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc.
Changing cultures, changing cuisines: Cultural transitions and dietary change in iron age, roman, and early medieval croatia
Authors: Lightfoot E. , Šlaus M. , O'Connell T.C.
Published: May 2012

Food is well‐known to encode social and cultural values, for example different social groups use different consumption patterns to act as social boundaries. When societies and cultures change, whether through drift, through population replacement or other factors, diet may also alter despite unchanging resource availability within a region. This study investigates the extent to which dietary change coincides with cultural change, to understand the effects of large‐scale migrations on the populations' diets. Through stable carbon and nitrogen isotope analysis of Iron Age, Roman, and Early Medieval human bone collagen, we show that in Croatia large‐scale cultural change led to significant changes in diet. The isotopic evidence indicates that Iron Age diet consisted of C3 foodstuffs with no isotopic evidence for the consumption of C4 or marine resources. With the Roman conquest, marine resources were added to the diet, although C3 foodstuffs continued to play an important role. In the Early Medieval period, this marine component was lost and varying amounts of C4 foodstuffs, probably millet, were added to the otherwise C3 diet. In both of these transitions it is likely that the changes in diet are related to the arrival of a new people into the area. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc.
The thumb of Miocene apes: New insights from Castell de Barberà (Catalonia, Spain)
Authors: Almécija Sergio , Alba David M. , Moyà‐Solà Salvador
Published: May 2012

Primate hands display a major selective compromise between locomotion and manipulation. The thumb may or may not participate in locomotion, but it plays a central role in most manipulative activities. Understanding whether or not the last common ancestor of humans and Pan displayed extant‐ape‐like hand proportions (i.e., relatively long fingers and a short thumb) can be clarified by the analysis of Miocene ape hand remains. Here we describe new pollical remains—a complete proximal phalanx and a partial distal phalanx—from the middle/late Miocene site of Castell de Barberà (ca., 11.2–10.5 Ma, Vallès‐Penedès Basin), and provide morphometric and qualitative comparisons with other available Miocene specimens as well as extant catarrhines (including humans). Our results show that all available Miocene taxa (Proconsul, Nacholapithecus, Afropithecus, Sivapithecus, Hispanopithecus, Oreopithecus, and the hominoid from Castell de Barberà) share a similar phalangeal thumb morphology: the phalanges are relatively long, and the proximal phalanges have a high degree of curvature, marked insertions for the flexor muscles, a palmarly bent trochlea and a low basal height. All these features suggest that these Miocene apes used their thumb with an emphasis on flexion, most of them to powerfully assist the fingers during above‐branch, grasping arboreal locomotion. Moreover, in terms of relative proximal phalangeal length, the thumb of Miocene taxa is intermediate between the long‐thumbed humans and the short‐thumbed extant apes. Together with previous evidence, this suggests that a moderate‐length hand with relatively long thumb—involved in locomotion—is the original hand morphotype for the Hominidae. Am J Phys Anthropol 148:436–450, 2012. © 2012 Wiley Periodicals, Inc.
Early anthropometric indices predict short stature and overweight status in a cohort of peruvians in early adolescence
Authors: Sterling Robie , Miranda J. Jaime , Gilman Robert H. , Cabrera Lilia , Sterling Charles R. , Bern Caryn , Checkley William
Published: May 2012

While childhood malnutrition is associated with increased morbidity and mortality, less well understood is how early childhood growth influences height and body composition later in life. We revisited 152 Peruvian children who participated in a birth cohort study between 1995 and 1998, and obtained anthropometric and bioimpedance measurements 11–14 years later. We used multivariable regression models to study the effects of childhood anthropometric indices on height and body composition in early adolescence. Each standard deviation decrease in length‐for‐age at birth was associated with a decrease in adolescent height‐for‐age of 0.7 SD in both boys and girls (all P < 0.001) and 9.7 greater odds of stunting (95% CI 3.3–28.6). Each SD decrease in length‐for‐age in the first 30 months of life was associated with a decrease in adolescent height‐for‐age of 0.4 in boys and 0.6 standard deviation in girls (all P < 0.001) and with 5.8 greater odds of stunting (95% CI 2.6–13.5). The effect of weight gain during early childhood on weight in early adolescence was more complex to understand. Weight‐for‐length at birth and rate of change in weight‐for‐length in early childhood were positively associated with age‐ and sex‐adjusted body mass index and a greater risk of being overweight in early adolescence. Linear growth retardation in early childhood is a strong determinant of adolescent stature, indicating that, in developing countries, growth failure in height during early childhood persists through early adolescence. Interventions addressing linear growth retardation in childhood are likely to improve adolescent stature and related‐health outcomes in adulthood. Am J Phys Anthropol 148:451–461, 2012. © 2012 Wiley Periodicals, Inc.
Ecology and sociality in a multilevel society: Ecological determinants of spatial cohesion in hamadryas baboons
Authors: Schreier Amy L. , Swedell Larissa
Published: May 2012

The multilevel society of hamadryas baboons, consisting of troops, bands, clans, and one‐male units (OMUs), is commonly perceived to be an effective means of adapting to variable food availability while allowing spatial cohesion in response to predator pressure. The relationship between these variables, however, has never been tested quantitatively. The Filoha site in Awash National Park, Ethiopia is ideally suited to such an investigation as it contains nutrient‐dense palm forests in addition to the Acacia scrublands typical of hamadryas distribution elsewhere, allowing comparisons of spatial cohesion across habitat types. Here, we use observations over a 1‐year period to examine the relationship between resource availability, perceived predator pressure, and spatial cohesion in a band of wild hamadryas baboons at Filoha. Our results demonstrate that the band was more likely to break into OMUs when foraging in habitats with lower food availability, and that the band fissioned into independent clans more often when preferred resources were not available. Furthermore, the baboons remained in larger aggregations for longer periods of time (i.e., prior to embarking on their daily foraging route) on mornings after predators were heard in the vicinity, and increased cohesion in response to encounters with people who may have been perceived as predators. These results support the notion that hamadryas baboons change their social groupings in response to both food availability and predation risk and that the ability of hamadryas bands to cleave and coalesce in response to changes in these factors underlies the evolution of the hamadryas modular social structure. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc.
A model for the evolution of developmental arrest in male orangutans
Authors: Pradhan Gauri R. , van Noordwijk Maria A. , van Schaik Carel
Published: May 2012

Male Sumatran orangutans (Pongo abelii) may delay for many years the acquisition of the full array of secondary sexual traits, including their characteristic cheek flanges. Such flexible developmental arrest is unique among male primates. Among male Bornean orangutans (Pongo pygmaeus) such long delays appear less common. Here, we develop a simple model to identify the conditions under which developmental arrest can be adaptive. We show that the baseline strategy (i.e., males are not susceptible to arrest) cannot be invaded by the flexible strategy (i.e., males can arrest their development when the conditions are unfavorable) when the potential for high‐ranking unflanged or flanged males to monopolize sexual access to females is low. In contrast, at high monopolization potential, the flexible strategy is the evolutionarily stable strategy. We also derive the proportion of flanged males in the population for each combination of monopolization values. This model concurs with field data that found a different monopolization potential between Bornean and Sumatran flanged males and a lower proportion of flanged males in the population in Sumatran orangutans. Pronounced developmental arrest is linked to very low adult mortality, which explains why it is so limited in its taxonomic distribution. Am J Phys Anthropol 2012. © 2012 Wiley Periodicals, Inc.