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1.  Where does the carbon go? A model–data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites 
The New Phytologist  2014;203(3):883-899.
Elevated atmospheric CO2 concentration (eCO2) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented.We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models.Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage.Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets.
PMCID: PMC4260117  PMID: 24844873
allocation; carbon (C); climate change; CO2 fertilisation; elevated CO2; free-air CO2 enrichment (FACE); models; phenology
2.  Optical Coherence Tomographic and Visual Results at Six Months after Transitioning to Aflibercept for Patients on Prior Ranibizumab or Bevacizumab Treatment for Exudative Age-Related Macular Degeneration (An American Ophthalmological Society Thesis) 
To study optical coherence tomographic (OCT) results and vision at 6 months after transition (post-Tx) from intravitreal bevacizumab and/or ranibizumab to aflibercept for treatment of neovascular age-related macular degeneration (nAMD). The null hypothesis was the lack of improvements in OCT metrics and vision outcome in study eyes at 6 months after transitioning from bevacizumab or ranibizumab to aflibercept.
This retrospective study assessed 6 monthly OCT (Cirrus) data after transitioning to aflibercept for eyes on prior Legacy-ranibizumab, Legacy-bevacizumab, or mixed treatment for nAMD. Outcome measures were subretinal fluid (SRF), cystoid macular edema (CME), pigment epithelial detachment (PED) heights and volumes, central 1- and 3-mm subfield, Macular Volume, and best spectacle and pinhole visual acuity (VA). A single masked investigator performed all OCT measurements.
One hundred eighty-nine eyes in 172 patients in Legacy-bevacizumab (95 eyes), Legacy-ranibizumab (84 eyes), or Mixed Group(10 eyes) were switched to aflibercept and followed for 6 months. Significant post-Tx reductions were noted in SRF/CME heights and volumes (all P<.001). Similar findings were noted for PED heights (122.8 μm vs 79.4 μm) and PED volumes (all P<.001). Post-Tx VA was better (20/43 vs 20/51, P<.001). There were no differences between Legacy-bevacizumab and Legacy-ranibizumab groups in OCT and VA changes. Post-Tx VA, SRF/CME, and PED heights and volumes were improved for Nonresponders (suboptimal response to bevacizumab/ranibizumab) (P=.001 to <.001), but not Responders (good responses to same). The only adverse event was a retinal pigment epithelial tear in one eye.
Significant improvements in vision and OCT metrics developed in Nonresponders but not in Responders. Post-Tx VA and OCT measures were similar for eyes on prior bevacizumab or ranibizumab. Post-Tx adverse events were uncommon.
PMCID: PMC4307397  PMID: 25646034
3.  The Walking Impairment Questionnaire Stair-Climbing Score predicts mortality in men and women with peripheral arterial disease 
Journal of vascular surgery  2012;55(6):1662-73.e2.
The Walking Impairment Questionnaire (WIQ) measures self-reported walking distance, walking speed, and stair-climbing ability in men and women with lower extremity peripheral arterial disease (PAD). We determined whether poorer WIQ scores are associated with higher all-cause and cardiovascular disease (CVD) mortality in individuals with and without PAD.
1048 men and women with and without PAD were identified from Chicago-area medical centers. Participants completed the WIQ at baseline and were followed for a median of 4.5 years. Cox proportional hazards models were used to relate baseline WIQ scores with mortality, adjusting for age, sex, race, the ankle brachial index (ABI), comorbidities, and other covariates.
461 participants (44.0%) died during follow-up, including 158 deaths from cardiovascular disease. PAD participants in the lowest baseline quartile of the WIQ stair-climbing scores had higher all-cause mortality (HR = 1.70 [95% Confidence Interval (CI) 1.08-2.66, p=0.02] and higher CVD mortality (HR = 3.11 [95% CI 1.30 – 7.47, p=0.01]) compared to those with the highest baseline WIQ stair climbing score. Among PAD participants there were no significant associations of lower baseline WIQ distance or speed scores with rates of all-cause mortality (p for trend = 0.20 and 0.07, respectively) or CVD mortality (p for trend = 0.51 and p for trend = 0.33, respectively). Among non-PAD participants there were no significant associations of lower baseline WIQ stair climbing, distance, or speed score with rates of all-cause mortality (p for trend = 0.94, 0.69, and 0.26, respectively) or CVD mortality (p for trend = 0.28, 0.68, and 0.78, respectively).
Among participants with PAD, lower WIQ stair climbing scores are associated with higher all-cause and CVD mortality, independently of the ABI and other covariates.
PMCID: PMC3963605  PMID: 22608041
4.  The Evolving Treatment Options for Diabetic Macular Edema 
Diabetic retinopathy (DR) is the leading cause of vision loss in working-age adults, and diabetic macular edema (DME) is the most common cause of visual impairment in individuals with DR. This review focuses on the pathophysiology, previous treatment paradigms, and emerging treatment options in the management of DME.
PMCID: PMC3782842  PMID: 24106640
5.  Deconstruction of the α4β2 Nicotinic Acetylchloine (nACh) Receptor Positive Allosteric Modulator des-Formylflustrabromine (dFBr) 
Journal of medicinal chemistry  2011;54(20):7259-7267.
des -Formylflustrabromine (dFBr; 1), perhaps the first selective positive allosteric modulator of α4β2 neuronal nicotinic acetylcholine (nACh) receptors, was deconstructed to determine which structural features contribute to its actions on receptors expressed in Xenopus ooycytes using 2-electrode voltage clamp techniques. Although the intact structure of 1 was found optimal, several deconstructed analogs retained activity. Neither the 6-bromo substituent nor the entire 2-position chain is required for activity. In particular, reduction of the olefinic side chain of 1, as seen with 6, not only resulted in retention of activity/potency but in enhanced selectivity for α4β2 versus α7 nACh receptors. Pharmacophoric features for the allosteric modulation of α4β2 nACh receptors by 1 were identified.
PMCID: PMC3200116  PMID: 21905680
6.  Fractures of capitellum: a review of 14 cases treated by open reduction and internal fixation with Herbert screws 
International Orthopaedics  2009;34(6):897-901.
Fourteen patients with displaced fractures of the humeral capitellum were treated by open reduction and internal fixation of the capitellar fragments with Herbert screws. As per Bryan and Morrey classification, there were seven type I fractures, one type II fracture, three type III fractures, and three non-unions. Patient outcomes were evaluated using the Mayo elbow performance score. The follow-up period ranged from three to seven years (mean 4.8 years). All patients had a stable, pain-free elbow with good range of motion at follow-up. There was no evidence of avascular necrosis or degenerative change.
PMCID: PMC2989024  PMID: 19894049
7.  Root Canal Morphology of Mandibular First Premolar in a Gujarati Population - an In Vitro Study 
Dental Research Journal  2011;8(3):118-122.
Knowledge about root canal morphology and its frequent variations can exert considerable influence on the success of endodontic treatment. The aim of this study was to survey the root canal morphology of mandibular first premolar teeth in a Gujarati population by decalcification and clearing technique.
One hundred thirty eight extracted mandibular first premolar teeth were collected from a Gujarati population. After decalcifying and clearing, the teeth were examined for tooth length, number of cusps and roots, number and shape of canal orifices and canal types.
The average length of mandibular first premolar teeth was 21.2 mm. All the teeth had 2 cusps. One hundred thirty four teeth (97.1%) had one root, and just 4 teeth (2.89%) had two roots. Mesial invagination of root was found in 21 teeth (15.21%). One canal orifice was found in 122 teeth (88.4%) and two canal orifices in 16 teeth (11.59%). Shape of orifices was found to be round in 46 teeth (33.33%), oval in 72 teeth (52.17%) and flattened ribbion in 20 teeth (14.49%). According to Vertucci's classification, Type I canal system was found in 93 teeth (67.39%), Types II,III,IV,V,and VI in 11 teeth (7.97%), 5 teeth (3.62%), 4 teeth (2.89%), 24 teeth (17.39%), and 1 tooth (0.72%) respectively.
Mandibular first premolar teeth were mostly found to have one root and Type I canal system.
PMCID: PMC3177385  PMID: 22013473
Canal orifice; Decalcification; Length of tooth; Mandibular first premolar; Root canal system
8.  Evaluation of 11 terrestrial carbon–nitrogen cycle models against observations from two temperate Free-Air CO2 Enrichment studies 
The New Phytologist  2014;202(3):803-822.
We analysed the responses of 11 ecosystem models to elevated atmospheric [CO2] (eCO2) at two temperate forest ecosystems (Duke and Oak Ridge National Laboratory (ORNL) Free-Air CO2 Enrichment (FACE) experiments) to test alternative representations of carbon (C)–nitrogen (N) cycle processes. We decomposed the model responses into component processes affecting the response to eCO2 and confronted these with observations from the FACE experiments. Most of the models reproduced the observed initial enhancement of net primary production (NPP) at both sites, but none was able to simulate both the sustained 10-yr enhancement at Duke and the declining response at ORNL: models generally showed signs of progressive N limitation as a result of lower than observed plant N uptake. Nonetheless, many models showed qualitative agreement with observed component processes. The results suggest that improved representation of above-ground–below-ground interactions and better constraints on plant stoichiometry are important for a predictive understanding of eCO2 effects. Improved accuracy of soil organic matter inventories is pivotal to reduce uncertainty in the observed C–N budgets. The two FACE experiments are insufficient to fully constrain terrestrial responses to eCO2, given the complexity of factors leading to the observed diverging trends, and the consequential inability of the models to explain these trends. Nevertheless, the ecosystem models were able to capture important features of the experiments, lending some support to their projections.
PMCID: PMC4288990  PMID: 24467623
carbon (C) storage; CO2 fertilization; ecosystem modelling; elevated CO2; Free-Air CO2 Enrichment (FACE); model evaluation; nitrogen (N) limitation; plant physiology

Results 1-8 (8)