bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adjoint Sensitivity of the Niño-3 Surface Temperature to Wind Forcing
Authors: Zhang Xuebin , Cornuelle Bruce , Roemmich Dean 
Published: March 2011

Abstract
The evolution of sea surface temperature (SST) over the eastern equatorial Pacific plays a significant role in the intense tropical air–sea interaction there and is of central importance to the El Niño–Southern Oscillation (ENSO) phenomenon. Effects of atmospheric fields (especially wind stress) and ocean state on the eastern equatorial Pacific SST variations are investigated using the Massachusetts Institute of Technology general circulation model (MITgcm) and its adjoint model, which can calculate the sensitivities of a cost function (in this case the averaged 0–30-m temperature in the Niño-3 region during an ENSO event peak) to previous atmospheric forcing fields and ocean state going backward in time. The sensitivity of the Niño-3 surface temperature to monthly zonal wind stress in preceding months can be understood by invoking mixed layer heat balance, ocean dynamics, and especially linear equatorial wave dynamics. The maximum positive sensitivity of the Niño-3 surface temperature to local wind forcing usually happens ~1–2 months before the peak of the ENSO event and is hypothesized to be associated with the Ekman pumping mechanism. In model experiments, its magnitude is closely related to the subsurface vertical temperature gradient, exhibiting strong event-to-event differences with strong (weak) positive sensitivity during La Niña (strong El Niño) events. The adjoint sensitivity to remote wind forcing in the central and western equatorial Pacific is consistent with the standard hypothesis that the remote wind forcing affects the Niño-3 surface temperature indirectly by exciting equatorial Kelvin and Rossby waves and modulating thermocline depth in the Niño-3 region. The current adjoint sensitivity study is consistent with a previous regression-based sensitivity study derived from perturbation experiments. Finally, implication for ENSO monitoring and prediction is also discussed.
Physical Mechanisms Regulating Summertime Rainfall over Northwestern Australia
Authors: Berry Gareth , Reeder Michael J. , Jakob Christian 
Published: March 2011

Abstract
Summertime (December–February) rainfall over northwestern Australia has increased significantly since the middle of the twentieth century. As a prerequisite to understanding the observed trend, this investigation examines the broad characteristics of rainfall and identifies the physical mechanisms by which rainfall in the region is initiated. This is achieved using a combination of in situ, spaceborne, and numerical reanalysis datasets.
Hourly pluviograph data and the Tropical Rainfall Measuring Mission (TRMM)-3B42 dataset show distinctly different diurnal cycles of rainfall in different geographical subregions; near the coast, rainfall rates peak in the midafternoon, whereas inland (near the maximum rainfall trend) the rainfall rate is largest overnight. These data also indicate that most of the summertime rain falls in events lasting 2–5 days. Analysis of the ECMWF Re-Analysis (ERA-Interim) demonstrates that convergence into the continental heat low controls the diurnal cycle of rainfall but cannot explain the synoptic variability.
Composites of wet and dry conditions from ERA-Interim expose synoptic-scale differences in the environmental flow. Prior to rain falling in the interior of northwestern Australia, there is a distinct shift in the origins of low-level air parcels, such that air with high convective available potential energy is advected from the tropical maritime regions, rather than from over the continent. Preliminary analysis suggests that these flow changes may be linked to transient synoptic disturbances such as midlatitude cyclones and monsoon lows. Rather than reflecting a large-scale change in the ocean state, these results imply that the observed increase in rainfall may be linked more closely to changes in the synoptic weather systems.
How should we teach everyday skills in dementia? A controlled study comparing implicit and explicit training methods
Authors: van Tilborg Ilse ADA , Kessels Roy PC , Hulstijn Wouter 
Published: March 2011

Objective: To compare the immediate and delayed effects of implicit and explicit training methods for everyday skills in patients with dementia. Design: Counterbalanced self-controlled cases series. Subjects: Convenience sample of 10 patients with dementia (Mini-Mental State Examination score between 15 and 26) and 16 age- and education-matched controls. Intervention: Two everyday tasks (using a microwave oven and a coffee machine) that were novel to all participants were trained in five 15-minute sessions. Each participant learned both tasks, one using an implicit learning method (modelling) and the other using an explicit learning method (providing verbal cues). Tasks and conditions were counterbalanced. Measures: The participants’ performance was videotaped to assess how well the tasks were performed before training, after each training session, and 7–10 days after the final training session. A rater, who was blind to the training method used, scored the number of correctly executed steps by viewing the videotapes. Results: The two training methods were effective in both the patient and healthy control groups, with there being a significant baseline-to-follow-up increase in the number of correctly completed steps (P < 0.001). There were no differences between the training methods (P = 0.16) and no significant interaction between training method and group (P = 0.31). Conclusions: Older patients with mild dementia are able to acquire new skills that are relevant for daily life, showing a similar rate of learning regardless of whether implicit or explicit learning techniques are used.
An initial exploration of the perceptual threshold test using electrical stimulation to measure arm sensation following stroke
Authors: Hedman Lois D , Sullivan Jane E 
Published: March 2011

Objective: To explore the viability of the perceptual threshold test using electrical stimulation to measure light touch sensation in the hands of stroke survivors. Design: Descriptive study. Setting: University research laboratory. Subjects: Twenty-nine adult community-dwelling chronic stroke survivors. Main measure(s): Perceptual threshold test using electrical stimulation, stroke rehabilitation assessment of movement, Nottingham sensory assessment for stereognosis, action research arm test, Fugl-Meyer assessment of sensation and motor activity log 14. Results: Perceptual threshold test using electrical stimulation mean threshold values were 1.23 (0.6) milliamperes (range 0.5–3.5) for the uninvolved side and 1.68 (0.91) milliamperes (range 0.5–4.5) for the involved side. The perceptual threshold test using electrical stimulation demonstrated excellent intra-rater reliability (intraclass correlation coefficient = 0.896 – uninvolved; 0.829 – involved). There was a statistically significant difference between the perceptual threshold test using electrical stimulation mean threshold values for the uninvolved and involved arms ( P = 0.003), but this significance did not hold for subjects who had normal sensation as measured by the Fugl-Meyer assessment of sensation ( P = 0.083). Low to nonexistent correlations were found between the perceptual threshold test using electrical stimulation and other measures of sensation, arm movement, activity and participation. Conclusions: The perceptual threshold test using electrical stimulation is a reliable and clinically feasible test with the potential to identify sensory capacity in stroke survivors with substantial sensory loss. Electrical sensory thresholds do not reflect overall sensory function or motor capabilities in stroke survivors.
A randomized controlled trial on the efficacy of intermittent cervical traction for patients with chronic neck pain
Authors: Chiu Thomas TW , Ng Joseph Kim-Fai , Walther-Zhang Barbro , Lin Rex JH , Ortelli Luc , Chua Siew Kuan 
Published: March 2011

Objective: To investigate the efficacy of intermittent cervical traction in the treatment of chronic neck pain over a 12-week follow-up. Design: A randomized controlled trial. Setting: Hospital-based outpatient practice. Subjects: Seventy-nine patients with chronic neck pain. Interventions: Subjects were randomly assigned to either experimental group ( n = 39, mean age = 50.5 ± 9.8) or control group ( n = 40, mean age = 48.8 ± 9.1). Experimental group received intermittent cervical traction and control group received infrared irradiation alone; twice a week over a period of six weeks. Outcome measurements: The values of Chinese version of the Northwick Park Neck Pain Questionnaire (NPQ), verbal numerical pain scale (VNPS), and cervical active range of motion (AROM) were measured at baseline, six-week and 12-week follow-up. Results: No significant differences were found between the two groups in the NPQ ( P > 0.05), VNPS ( P > 0.05) and AROM ( P > 0.05).
Efficacy of gait trainer as an adjunct to traditional physical therapy on walking performance in hemiparetic cerebral palsied children: a randomized controlled trial
Authors: Gharib Nevein MM , El-Maksoud Gehan M Abd , Rezk-Allah Soheir S 
Published: March 2011

Objective: To assess the effects of additional gait trainer assisted walking exercises on walking performance in children with hemiparetic cerebral palsy. Design: A randomized controlled study. Setting: Paediatric physical therapy outpatient clinic. Subjects: Thirty spastic hemiparetic cerebral palsied children of both sexes (10–13 years – 19 girls and 11 boys). Methods: Children were randomly assigned into two equal groups; experimental and control groups. Participants in both groups received a traditional physical therapy exercise programme. Those in the experimental group received additional gait trainer based walking exercises which aimed to improve walking performance. Treatment was provided three times per week for three successive months. Main measures: Children received baseline and post-treatment assessments using Biodex Gait Trainer 2 assessment device to evaluate gait parameters including: average step length, walking speed, time on each foot (% of gait cycle) and ambulation index. Results: Children in the experimental group showed a significant improvement as compared with those in the control group. The ambulation index was 75.53±7.36 (11.93 ± 2.89 change score) for the experimental group and 66.06 ± 5.48 (2.13 ± 4.43 change score) for the control group ( t = 3.99 and P = 0.0001). Time of support for the affected side was 42.4 ± 3.37 (7 ± 2.20 change score) for the experimental group and 38.06 ± 4.63 (3.33 ± 6.25 change score) for the control group ( t = 2.92 and P = 0.007). Also, there was a significant improvement in step length and walking speed in both groups. Conclusion: Gait trainer combined with traditional physiotherapy increase the chance of improving gait performance in children with spastic hemiparetic cerebral palsy.
Early Structural and Functional Outcomes for Arthroscopic Double-Row Transosseous-Equivalent Rotator Cuff Repair
Authors: Toussaint Bruno , Schnaser Erik , Bosley Jacob , Lefebvre Yves , Gobezie Reuben 
Published: March 2011

Background: The arthroscopic double-row transosseous-equivalent (TOE) rotator cuff repair is growing in popularity. The current body of literature supports this technique; however, the number of patients in these studies is relatively small. The authors conducted this study to learn more about the natural history of this construct in a large sample of patients. Hypothesis: The double-row TOE rotator cuff repair will have an acceptable structural failure rate with improved clinical outcomes at 1-year follow-up. Study Design: Case series; Level of evidence, 4. Methods: Between June 2006 and October 2007, 225 patients underwent an all-arthroscopic rotator cuff repair at 2 surgical centers. A total of 155 TOE primary rotator cuff repairs were performed, and 154 of these patients met the inclusion criteria. Assessment of structural integrity was based on evaluation of postoperative magnetic resonance imaging or computed tomography arthrogram at a minimum of 12 months after surgery. The Constant scores, visual analog pain scale, range of motion, strength, and complications were the clinical outcomes analyzed for the study. Seventeen patients (of 154) had postoperative shoulder stiffness at follow-up. Results: The 154 patients were clinically and radiologically evaluated at a mean of 15 months postoperatively (range, 12-26.1 months). The study included 47 small (30.5%), 89 large (57.1%), and 19 massive (12.3%) rotator cuff tears. Analysis of postoperative imaging demonstrated that 92%, 83%, and 84% of the small, large, and massive rotator cuff tears, respectively, were intact. The mean Constant score improved from 44.42 points preoperatively to 80.47 points postoperatively ( P < .001). The mean preoperative pain score improved from 3.83 to 12.77 ( P < .001) postoperatively. The mean forward flexion improved from 123.06° preoperatively to 162.39° postoperatively ( P < .001). Seventeen patients (of 154) had postoperative shoulder stiffness at follow-up. Conclusion: The short-term results of this study indicate that the clinical outcomes and structural integrity of TOE double-row rotator cuff repair (the suture-bridge technique) have results that compare favorably with those reported for other double-row suture anchor techniques employed in rotator cuff repairs. Long-term follow-up will be necessary to determine if the durability of these repairs and the structural integrity of these constructs maintain their performance over time.
Exercise training restores the endothelial response to vascular growth factors in patients with stable coronary artery disease
Authors: Beck Ephraim B , Erbs Sandra , Möbius-Winkler Sven , Adams Volker , Woitek Felix J , Walther Thomas , Hambrecht R , Mohr Friedrich-Wilhelm , Stumvoll Michael , Blüher Matthias , Schuler Gerhard , Linke Axel 
Published: March 2011

Objective: Exercise training partially corrects endothelial dysfunction in patients with coronary artery disease (CAD). Growth factors like vascular endothelial growth factor (VEGF) as well as erythropoietin (EPO) are known to modulate the bioavailability of nitric oxide and, thereby, contribute to the maintenance of a normal vascular tone. The aim of the present study was to determine the impact of 4 weeks of exercise training on circulating growth factors and to elucidate their involvement in the training-induced changes in vasomotion in patients with CAD. Methods and results: A total of 39 patients were enrolled (training group: n = 20; control group: n = 19). At start of study and after 4 weeks, average peak flow velocity (APV) of the left internal mammary artery (LIMA) in response to acetylcholine was measured invasively in the treatment and control groups. Serum concentrations of VEGF and EPO were determined by enzyme-linked immunosorbent assay. After exercise training, LIMA APV in response to acetylcholine was increased by 93% (from 69 ± 17% at start of study to 133 ± 16% at 4 weeks, p < 0.01 vs. start of study and control). At start of study, there was no association between any of the vascular growth factors and endothelial function. However, after exercise training a close correlation was apparent between the acetylcholine-induced change in APV and EPO ( r = 0.69, p < 0.01) and VEGF ( r = 0.76, p < 0.01) serum concentrations. In the control group, these correlations were not evident and there was no change in endothelial function either. Conclusion: Exercise training improves agonist-mediated endothelium-dependent vasodilatation in CAD, partially through a restoration of the endothelial response to EPO and VEGF.
Vav guanine nucleotide exchange factors link hyperlipidemia and a prothrombotic state
Authors: Chen Kan , Li Wei , Major Jennifer , Rahaman Shaik Ohidar , Febbraio Maria , Silverstein Roy L. 
Published: March 2011

AbstractPlatelet hyperactivity associated with hyperlipidemia contributes to development of a pro-thrombotic state. We previously showed that oxidized LDL (oxLDL) formed in the setting of hyperlipidemia and atherosclerosis initiated a CD36-mediated signaling cascade leading to platelet hyperactivity. We now show that the guanine nucleotide exchange factors Vav1 and Vav3 were tyrosine phosphorylated in platelets exposed to oxLDL. Pharmacologic inhibition of src family kinases abolished Vav1 phosphorylation by oxLDL in vitro. Coimmunoprecipitations revealed the tyrosine phosphorylated form of src kinase Fyn was associated with Vav1 in platelets exposed to oxLDL. Using a platelet aggregation assay, we demonstrated that Vav1 deficiency, Fyn deficiency, or Vav1/Vav3 deficiency protected mice from diet-induced platelet hyperactivity. Furthermore, flow cytometric analysis revealed that Vav1/Vav3 deficiency significantly inhibited oxLDL-mediated integrin αIIbβIII activation of platelets costimulated with ADP. Finally, we showed with an in vivo carotid artery thrombosis model that genetic deletion of Vav1 and Vav3 together may prevent the development of occlusive thrombi in mice fed a high-fat diet. These findings implicate Vav proteins in oxLDL-mediated platelet activation and suggest that Vav family member(s) may act as critical modulators linking a prothrombotic state and hyperlipidemia.
Human T-lymphotropic type 1 virus p30 inhibits homologous recombination and favors unfaithful DNA repair
Authors: Baydoun Hicham H. , Pancewicz Joanna , Nicot Christophe 
Published: March 2011

AbstractWhereas oncogenic retroviruses are common in animals, human T-lymphotropic virus 1 (HTLV-1) is the only transmissible retrovirus associated with cancer in humans and is etiologically linked to adult T-cell leukemia. The leukemogenesis process is still largely unknown, but relies on extended survival and clonal expansion of infected cells, which in turn accumulate genetic defects. A common feature of human tumor viruses is their ability to stimulate proliferation and survival of infected pretumoral cells and then hide by establishing latency in cells that have acquired a transformed phenotype. Whereas disruption of the DNA repair is one of the major processes responsible for the accumulation of genomic abnormalities and carcinogenesis, the absence of DNA repair also poses the threat of cell-cycle arrest or apoptosis of virus-infected cells. This study describes how the HTLV-1 p30 viral protein inhibits conservative homologous recombination (HR) DNA repair by targeting the MRE11/RAD50/NBS1 complex and favors the error-prone nonhomologous-end–joining (NHEJ) DNA-repair pathway instead. As a result, HTLV-1 p30 may facilitate the accumulation of mutations in the host genome and the cumulative risk of transformation. Our results provide new insights into how human tumor viruses may manipulate cellular DNA-damage responses to promote cancer.
Mechanism for phosphatidylserine-dependent erythrophagocytosis in mouse liver
Authors: Lee Sung-Jin , Park Seung-Yoon , Jung Mi-Yeon , Bae Sang Mun , Kim In-San 
Published: March 2011

AbstractAged or damaged RBCs are effectively removed from the blood circulation by Kupffer cells in the liver, but little is known regarding the mechanism of the clearance process. Here we show that stabilin-1 and stabilin-2 in hepatic sinusoidal endothelial cells (HSECs) are critical in effectively clearing damaged RBCs in mouse liver. Damaged RBCs and phosphatidylserine (PS)–coated beads were effectively sequestered in the hepatic sinusoid regardless of the presence of Kupffer cells, suggesting a role for HSECs in PS-dependent sequestration of PS-exposed RBCs in the liver. HSECs mediate tethering of damaged RBCs in a PS-dependent manner via stabilin-1 and stabilin-2. In a sinusoid-mimicked coculture system consisting of macrophages layered over HSECs, there was significant enhancement of the phagocytic capacity of macrophages, and this was mediated by stabilin-1 and stabilin-2 in HSECs. Liver-specific knockdown of stabilin-1 and stabilin-2 inhibited the sequestration of damaged RBCs in the hepatic sinusoid and delayed the elimination of damaged cells in an in vivo animal model. Thus, the roles of stabilin-1 and stabilin-2 in hepatic sequestration of PS-exposed RBCs may represent a potential mechanism for the clearance of damaged RBCs by Kupffer cells and for the control of some pathologic conditions such as hemolytic anemia.
Thymic T-cell development in allogeneic stem cell transplantation
Authors: Krenger Werner , Blazar Bruce R. , Holländer Georg A. 
Published: March 2011

AbstractCytoreductive conditioning regimens used in the context of allogeneic hematopoietic cell transplantation (HCT) elicit deficits in innate and adaptive immunity, which predispose patients to infections. As such, transplantation outcomes depend vitally on the successful reconstruction of immune competence. Restoration of a normal peripheral T-cell pool after HCT is a slow process that requires the de novo production of naive T cells in a functionally competent thymus. However, there are several challenges to this regenerative process. Most notably, advanced age, the cytotoxic pretransplantation conditioning, and posttransplantation alloreactivity are risk factors for T-cell immune deficiency as they independently interfere with normal thymus function. Here, we discuss preclinical allogeneic HCT models and clinical observations that have contributed to a better understanding of the transplant-related thymic dysfunction. The identification of the cellular and molecular mechanisms that control regular thymopoiesis but are altered in HCT patients is expected to provide the basis for new therapies that improve the regeneration of the adaptive immune system, especially with functionally competent, naive T cells.