bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary investigation of multiparametric strain Z‐score (MPZS) computation using displacement encoding with simulated echoes (DENSE) and radial point interpretation method (RPIM)
Authors: Kar Julia , Cupps Brian , Zhong Xiaodong , Koerner Danielle , Kulshrestha Kevin , Neudecker Samuel , Bell Jennifer , Craddock Heidi , Pasque Michael
Published: April 2016

Purpose

To describe and assess an automated normalization method for identifying sentinel (septal) regions of myocardial dysfunction in nonischemic, nonvalvular dilated cardiomyopathy (DCM), using an unprecedented combination of the navigator‐gated 3D spiral displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI), radial point interpolation (RPIM) and multiparametric strain z‐score (MPZS).

Materials and Methods

Navigator‐gated 3D spiral DENSE, in a 1.5T MRI machine, was used for acquiring the displacement encoded complex images, MR Analytical Software System (MASS) for automated boundary detection and automated meshfree RPIM for left‐ventricular (LV) myocardial strain computation to analyze MPZS in 36 subjects (with n = 17 DCM patients). Pearson's r correlation established relations between global/sentinel MPZS and ejection fraction (EF). The time taken for combined RPIM‐MPZS computations was recorded.

Results

Maximum MPZS differences were seen between anteroseptal and posterolateral regions in the base (2.0 ± 0.3 vs. 0.9 ± 0.5) and the mid‐wall (2.1 ± 0.4 vs. 1.0 ± 0.4). These regional differences were found to be consistent with historically documented septal injury in nonischemic DCM. Correlations were 0.6 between global MPZS and EF, and 0.7 between sentinel MPZS and EF. The time taken for combined RPIM‐MPZS computations per subject was 18.9 ± 5.9 seconds.

Conclusion

Heterogeneous contractility found in the sentinel regions with the current automated MPZS computation scheme and the correlation found between MPZS and EF may lead to the creation of a new clinical metric in LV DCM surveillance. J. MAGN. RESON. IMAGING 2016;44:993–1002.
Nonsurgical treatment and early return to activity leads to improved Achilles tendon fatigue mechanics and functional outcomes during early healing in an animal model
Authors: Freedman Benjamin R. , Gordon Joshua A. , Bhatt Pankti R. , Pardes Adam M. , Thomas Stephen J. , Sarver Joseph J. , Riggin Corinne N. , Tucker Jennica J. , Williams Alexis W. , Zanes Robert C. , Hast Michael W. , Farber Daniel C. , Silbernagel Karin G. , Soslowsky Louis J.
Published: April 2016

Achilles tendon ruptures are common and devastating injuries; however, an optimized treatment and rehabilitation protocol has yet to be defined. Therefore, the objective of this study was to investigate the effects of surgical repair and return to activity on joint function and Achilles tendon properties after 3 weeks of healing. Sprague–Dawley rats (N = 100) received unilateral blunt transection of their Achilles tendon. Animals were then randomized into repaired or non‐repaired treatments, and further randomized into groups that returned to activity after 1 week (RTA1) or after 3 weeks (RTA3) of limb casting in plantarflexion. Limb function, passive joint mechanics, and tendon properties (mechanical, organizational using high frequency ultrasound, histological, and compositional) were evaluated. Results showed that both treatment and return to activity collectively affected limb function, passive joint mechanics, and tendon properties. Functionally, RTA1 animals had increased dorsiflexion ROM and weight bearing of the injured limb compared to RTA3 animals 3‐weeks post‐injury. Such functional improvements in RTA1 tendons were evidenced in their mechanical fatigue properties and increased cross sectional area compared to RTA3 tendons. When RTA1 was coupled with nonsurgical treatment, superior fatigue properties were achieved compared to repaired tendons. No differences in cell shape, cellularity, GAG, collagen type I, or TGF‐β staining were identified between groups, but collagen type III was elevated in RTA3 repaired tendons. The larger tissue area and increased fatigue resistance created in RTA1 tendons may prove critical for optimized outcomes in early Achilles tendon healing following complete rupture. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2172–2180, 2016.
N‐acetyl cysteine protects cells from chondrocyte death induced by local anesthetics
Authors: Kim Ra Jeong , Kang Jae‐Ran , Hah Young‐Sool , Park Hyung Bin
Published: April 2016

Local anesthetics (LA) are among the drugs most frequently used for musculoskeletal problems, in procedures ranging from diagnosis to postoperative pain control. Chondrocyte toxicity induced by LA is an emerging area of concern. The purpose of this study was to determine whether N‐acetyl cysteine (NAC), an antioxidant, will exert cytoprotective effects against chondrocyte death induced by LA. Primary cultured human chondrocytes were used for this study. This study used control, NAC, LA, and NAC‐LA groups. Cytotoxicity was induced in the LA subgroups and their paired NAC‐LA subgroups through exposure to ropivacaine (0.075%), bupivacaine (0.05%), or lidocaine (0.2%) for 24 h. The NAC‐LA subgroups were exposed to 10 mM NAC for 1 h, before LA exposure. These study groups were evaluated for rates of cell viability, apoptosis, necrosis, intracellular ROS production, and caspase‐3/7 activity. Cell viability in all LA subgroups was significantly lower than in the control group (p < 0.001). Cell viability in the NAC‐LA subgroups was significantly higher than in their paired LA subgroups (p < 0.001). In the LA subgroups, rates of apoptosis and necrosis, intracellular ROS production, and caspase‐3/7 activity were significantly higher than in the control group (p ≤ 0.029). In the NAC‐LA subgroups, rates of apoptosis and necrosis, intracellular ROS production, and caspase‐3/7 activity were significantly lower than in their paired LA subgroups (p ≤ 0.023). These results indicate that N‐acetyl cysteine, an antioxidant, has cytoprotective effects against LA‐induced toxicity to chondrocytes in vitro. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:297–303, 2017.
Interaction between living bone particles and rhBMP‐2 in large segmental defect healing in the rat femur
Authors: Liu Fangjun , Wells James W. , Porter Ryan M. , Glatt Vaida , Shen Zhenxin , Schinhan Martina , Ivkovic Alan , Vrahas Mark S. , Evans Christopher H. , Ferreira Elisabeth
Published: April 2016

Orthopedic surgeons sometimes combine recombinant, human BMP‐2 with autograft bone when dealing with problematic osseous fractures. Although some case reports indicate success with this off‐label strategy, there have been no randomized controlled trials. Moreover, a literature search revealed only one pre‐clinical study and this was in a cranial defect model. The present project examined the consequences of combining BMP‐2 with particles of living bone in a rat femoral defect model. Human bone particles were recovered with a reamer‐irrigator‐aspirator (RIA). To allow acceptance of the xenograft as surrogate autograft, rats were administered an immunosuppressive cocktail that does not interfere with bone healing. Implantation of 200 µg living bone particles generated a small amount of new bone and defects did not heal. Graded amounts of BMP‐2 that alone provoked no healing (1.1 µg), borderline healing (5.5 µg), or full healing (11 µg) were added to this amount of bone particles. Addition of BMP‐2 (1.1 µg) increased osteogenesis, and produced bridging in 2 of 7 defects. The combination of BMP‐2 (5.5 µg) and bone particles made healing more reliable and advanced the maturation of the regenerate. Bone formation with BMP‐2 (11 µg) and bone particles showed improved maturation. Thus, the combination of autograft and BMP‐2 may be helpful clinically under conditions where the healing response is suboptimal. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2137–2145, 2016.

Clinical significance

These data support the clinical use of recombinant, human BMP‐2 with autograft bone when treating large segmental osseous defects. The combination leads to greater bone formation and accelerates the maturation of the regenerate.
Movement and survival of an amphibian in relation to sediment and culvert design
Authors: Honeycutt R. Ken , Lowe Winsor H. , Hossack Blake R.
Published: April 2016

Habitat disturbance from stream culverts can affect aquatic organisms by increasing sedimentation or forming barriers to movement. Land managers are replacing many culverts to reduce these negative effects, primarily for stream fishes. However, these management actions are likely to have broad implications for many organisms, including amphibians in small streams. To assess the effects of culverts on movement and survival of the Idaho giant salamander (Dicamptodon aterrimus), we used capture‐mark‐recapture surveys and measured sediment in streams with 2 culvert types (i.e., unimproved culverts, improved culverts) and in streams without culverts (i.e., reference streams). We predicted culverts would increase stream sediment levels, limit movement, and reduce survival of Idaho giant salamanders. We also determined the effect of sediment levels on survival of salamanders because although sediment is often associated with distribution and abundance of stream amphibians, links with vital rates remain unclear. To estimate survival, we used a spatial Cormack–Jolly–Seber (CJS) model that explicitly incorporated information on movement, eliminating bias in apparent survival estimated from traditional (i.e., non‐spatial) CJS models caused by permanent emigration beyond the study area. To demonstrate the importance of using spatial data in studies of wildlife populations, we compared estimates from the spatial CJS to estimates of apparent survival from a traditional CJS model. Although high levels of sediment reduced survival of salamanders, culvert type was unrelated to sediment levels or true survival of salamanders. Across all streams, we documented only 15 movement events between study reaches. All movement events were downstream, and they occurred disproportionately in 1 stream, which precluded measuring the effect of culvert design on movement. Although movement was low overall, the variance among streams was high enough to bias estimates of apparent survival compared to true survival. Our results suggest that where sedimentation occurs from roads and culverts, survival of the Idaho giant salamander could be reduced. Though culverts clearly do not completely block downstream movements of Idaho giant salamanders, the degree to which culvert improvements affect movements under roads in comparison to unimproved culverts remains unclear, especially for rare, but potentially important, upstream movements. © 2016 The Wildlife Society.
Recovery of American peregrine falcons along the upper Yukon River, Alaska
Authors: Ambrose Skip , Florian Chris , Ritchie Robert J. , Payer David , O'brien Robert M.
Published: April 2016

American peregrine falcons (Falco peregrinus anatum) throughout North America declined following the introduction of dichlorodiphenyltrichloroethane (DDT) in 1947. In the 1960s, intensive studies were initiated in many areas of North America, including interior Alaska, to determine the cause of the decline and assess population status. From 1977 to 2015, we studied peregrine falcons along a 265‐km section of the upper Yukon River in east‐central Alaska. We counted occupied territories, documented breeding success and productivity, and collected unhatched eggs for contaminant analysis. We observed 1,602 occupied territories and 2,349 nestlings. Annual breeding success averaged 64%, and annual productivity averaged 1.54 nestlings/territory and 2.38 nestlings/successful territory. Annual rates of increase in the number of occupied territories were greatest in the late 1970s and 1980s (8.6%), moderate in the 1990s (2.8%), and least in the 2000s (1.5%). Reproductive metrics were highest in the late 1970s and 1980s, declining in recent years. As the number of occupied territories increased (14–60) and average nearest neighbor distance decreased (from 9.8 km to 2.6 km), breeding success declined (from 71% in the 1980s to 57% in the 2000s). Productivity, as measured by nestlings per occupied territory, declined (from 1.84 in the 1980s to 1.29 in the 2000s). Nestlings per successful territory also declined from 2.56 in the 1980s to 2.25 in the 2000s. Survey data for 1966–2015 reveal a declining population in the 1960s and early 1970s, increasing in the late 1970s through the early 2000s, and apparently stabilizing in recent years. The recovery of this local population took roughly 40 years, from a low of 12 occupied territories in early 1970s to 60 in 2012–2014. Importantly, the recovery of American peregrine falcons in Alaska occurred without captive breeding, releases, or nest site manipulations. Long‐term studies are essential in fully understanding the biology of any species, and this study provides insight into the unaided, natural recovery of American peregrine falcons in Alaska. © 2016 The Wildlife Society.
Buchbesprechung: Lebensmittelchemie 2/2016
Authors: Schneider R.
Published: April 2016

Enzyme, Struktur, Kinetik und Anwendungen von Hans Bisswanger.
Protective role of normothermic machine perfusion during reduced‐size liver transplantation in pigs
Authors: Zhang Zhi‐Bin , Gao Wei , Shi Yuan , Liu Lei , Ma Ning , Chen Jing , Zhu Zhi‐Jun
Published: April 2016

The purpose of this study is to explore whether normothermic machine perfusion (NMP) preservation is superior to cold preservation during reduced‐size liver transplantation (RSLT) in pigs. Twenty‐four healthy Ba‐Ma mini pigs were used (aged >13 months; weight 25‐35 kg; regardless of sex). The animals were randomized into 2 groups. In group A (NMP), donor livers were harvested without warm ischemia time and heartbeats and then were connected to the NMP system to reduce the livers' size under the normothermic condition. In group B (University of Wisconsin [UW] solution), donor livers were harvested without warm ischemia time and heartbeats after being perfused by UW solution and were then preserved in 0°C‐4°C UW solution to reduce the livers' size under cold conditions. After that, liver transplantation without venovenous bypass was performed. General RSLT information of the pigs from the 2 groups was recorded; the serological indices were measured; and routine pathological examination of liver tissue was observed. A significant difference was observed in the intraoperative bleeding between the 2 groups (P < 0.05), whereas no significant difference was found in the other indices (all P > 0.05). Significant differences of alanine aminotransferase levels, aspartate aminotransferase levels, and lactate dehydrogenase levels between the 2 groups were observed between postoperative days 3 and 5 (P < 0.05). Significant differences of lactic acid levels between the 2 groups were observed between postoperative days 2 and 5 (P < 0.05). Compared with the cold preservation group, the liver tissues of the NMP preservation group only rarely experienced liver cell necrosis and maintained integrities in the hepatic sinusoid spaces and endothelial cells. In conclusion, NMP preservation is superior to cold preservation during RSLT in pigs. Liver Transplantation 22 968–978 2016 AASLD
An infinite natural sum
Authors: Lipparini Paolo
Published: April 2016

As far as algebraic properties are concerned, the usual addition on the class of ordinal numbers is not really well behaved; for example, it is not commutative, nor left cancellative etc. In a few cases, the natural Hessenberg sum is a better alternative, since it shares most of the usual properties of the addition on the naturals.
A countably infinite iteration of the natural sum has been used in a recent paper by Väänänen and Wang, with applications to infinitary logics. We present a detailed study of this infinitary operation, showing that there are many similarities with the ordinary infinitary sum, providing an order theoretical characterization, and finding connections with certain kinds of infinite mixed sums.
Oligomeropathies and pathogenesis of Alzheimer and Parkinson's diseases
Authors: Forloni Gianluigi , Artuso Vladimiro , La Vitola Pietro , Balducci Claudia
Published: April 2016

The term oligomeropathies defines the neurodegenerative disorders associated with protein misfolding, where small soluble aggregates (oligomers 4‐200 KDa) are the cause of neuronal dysfunction and are responsible for spreading the pathology. The ability of these soluble β‐sheet conformers to induce neuronal damage has been investigated in direct challenge with the monomeric and fibrillary structures, showing that only the oligomeric species affected the neurons. β amyloid oligomers were initially purified from Alzheimer brains and obtained using synthetic peptides. Together with the neuronal death, synaptic dysfunction, loss of spines, and LTP impairment were seen with the direct application of β amyloid oligomers. Similar results have been described with proteins associated with other neurodegenerative disorders. The biological activities of oligomeric forms of α synuclein have been described in Parkinson's disease and Lewy body dementia. Detrimental effects have been associated with the oligomeric forms of prion, tau, and huntingtin, the key proteins in prion diseases, frontotemporal dementia, and Huntington's disease, respectively. The molecular mechanisms of the oligomer‐related toxic effects can be summarized under three headings: nonspecific perturbance of cellular and intracellular membranes, specific interaction with various cellular entities, and amyloid pore channel formation. To characterize and distinguish oligomer actions better, we compared the ability of β amyloid and α synuclein oligomers to induce cognitive impairment when applied directly into the brain in the same acute mouse model. We also investigated the role of inflammatory components. © 2016 International Parkinson and Movement Disorder Society
Fibroblast Growth Factor 21 As an Emerging Therapeutic Target for Type 2 Diabetes Mellitus
Authors: So Wing Yan , Leung Po Sing
Published: April 2016

Fibroblast growth factor (FGF) 21 is a distinctive member of the FGF family that functions as an endocrine factor. It is expressed predominantly in the liver, but is also found in adipose tissue and the pancreas. Pharmacological studies have shown that FGF21 normalizes glucose and lipid homeostasis, thereby preventing the development of metabolic disorders, such as obesity and diabetes. Despite growing evidence for the therapeutic potential of FGF21, paradoxical increases of FGF21 in different disease conditions point to the existence of FGF21 resistance. In this review, we give a critical appraisal of recent advances in the understanding of the regulation of FGF21 production under various physiological conditions, its antidiabetic actions, and the clinical implications. We also discuss recent preclinical and clinical trials using engineered FGF21 analogs in the management of diabetes, as well as the potential side effects of FGF21 therapy.
Incorporating dixon multi‐echo fat water separation for novel quantitative magnetization transfer of the human optic nerve in vivo
Authors: Smith Alex K. , Dortch Richard D. , Dethrage Lindsey M. , Lyttle Bailey D. , Kang Hakmook , Welch E. Brian , Smith Seth A.
Published: April 2016

Purpose

The optic nerve (ON) represents the sole pathway between the eyes and brain; consequently, diseases of the ON can have dramatic effects on vision. However, quantitative magnetization transfer (qMT) applications in the ON have been limited to ex vivo studies, in part because of the fatty connective tissue that surrounds the ON, confounding the magnetization transfer (MT) experiment. Therefore, the aim of this study was to implement a multi‐echo Dixon fat‐water separation approach to remove the fat component from MT images.

Methods

MT measurements were taken in a single slice of the ON and frontal lobe using a three‐echo Dixon readout, and the water and out‐of‐phase images were applied to a two‐pool model in ON tissue and brain white matter to evaluate the effectiveness of using Dixon fat‐water separation to remove fatty tissue from MT images.

Results

White matter data showed no significant differences between image types; however, there was a significant increase (p < 0.05) in variation in the out‐of‐phase images in the ON relative to the water images.

Conclusions

The results of this study demonstrate that Dixon fat‐water separation can be robustly used for accurate MT quantification of anatomies susceptible to partial volume effects resulting from fat. Magn Reson Med 77:707–716, 2017. © 2016 International Society for Magnetic Resonance in Medicine
LORAKS makes better SENSE: Phase‐constrained partial fourier SENSE reconstruction without phase calibration
Authors: Kim Tae Hyung , Setsompop Kawin , Haldar Justin P.
Published: April 2016

Purpose

Parallel imaging and partial Fourier acquisition are two classical approaches for accelerated MRI. Methods that combine these approaches often rely on prior knowledge of the image phase, but the need to obtain this prior information can place practical restrictions on the data acquisition strategy. In this work, we propose and evaluate SENSE‐LORAKS, which enables combined parallel imaging and partial Fourier reconstruction without requiring prior phase information.

Theory and Methods

The proposed formulation is based on combining the classical SENSE model for parallel imaging data with the more recent LORAKS framework for MR image reconstruction using low‐rank matrix modeling. Previous LORAKS‐based methods have successfully enabled calibrationless partial Fourier parallel MRI reconstruction, but have been most successful with nonuniform sampling strategies that may be hard to implement for certain applications. By combining LORAKS with SENSE, we enable highly accelerated partial Fourier MRI reconstruction for a broader range of sampling trajectories, including widely used calibrationless uniformly undersampled trajectories.

Results

Our empirical results with retrospectively undersampled datasets indicate that when SENSE‐LORAKS reconstruction is combined with an appropriate k‐space sampling trajectory, it can provide substantially better image quality at high‐acceleration rates relative to existing state‐of‐the‐art reconstruction approaches.

Conclusion

The SENSE‐LORAKS framework provides promising new opportunities for highly accelerated MRI. Magn Reson Med 77:1021–1035, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Absence of anti–HMG‐CoA reductase autoantibodies in severe self‐limited statin‐related myopathy
Authors: Floyd James S. , Brody Jennifer A. , Tiniakou Eleni , Psaty Bruce M. , Mammen Andrew
Published: April 2016

Introduction: Patients with self‐limited statin‐related myopathy improve spontaneously when statins are stopped. In contrast, patients with statin‐associated autoimmune myopathy have autoantibodies recognizing 3‐hydroxy‐3‐methyl‐glutaryl‐coenzyme A reductase (HMGCR) and usually require immunosuppressive therapy to control their disease. On initial presentation, it can sometimes be difficult to distinguish between these 2 diseases, as both present with muscle pain, weakness, and elevated serum creatine kinase (CK) levels. The goal of this study was to determine whether patients with severe self‐limited statin‐related myopathy also make anti‐HMGCR autoantibodies. Methods: We screened 101 subjects with severe self‐limited cerivastatin‐related myopathy for anti‐HMGCR autoantibodies. Results: No patient with severe self‐limited cerivastatin‐related myopathy had anti‐HMGCR autoantibodies. Conclusion: Anti‐HMGCR autoantibody testing can be used to help differentiate whether a patient has self‐limited myopathy due to cerivastatin or autoimmune statin‐associated myopathy; these findings may apply to other statins as well. Muscle Nerve 54: 142–144, 2016
Pelvic floor dysfunction and sensory impairment: Current evidence
Authors: Mahoney Charlotte , Smith Anthony , Marshall Andy , Reid Fiona
Published: April 2016

Aims

To explore the role of sensory nerve impairment in women with pelvic organ prolapse, painful bladder syndrome, urinary and fecal incontinence, and sexual dysfunction.

Methods

Medline and Embase were searched for articles in which sensory testing, either quantitative sensory testing or current perception thresholds, had been used to evaluate women with pelvic organ prolapse, stress and urge urinary incontinence, fecal incontinence and female sexual dysfunction. All search terms were expanded within each database prior to searching.

Results

Research to date has included small numbers of participants, used poorly matched controls, lacked a systemic sensory examination and applied non‐standardized sensory testing techniques. However, the evidence suggests women with pelvic organ prolapse demonstrate sensory dysfunction. The role of sensory impairment in stress urinary incontinence is inconclusive. In women with urge urinary incontinence there is some evidence to suggest it may be urethrally mediated. Women with painful bladder syndrome may have more sensitive nerve endings which are unable to ignore repeated stimuli. Sensory impairment is common in women with sexual dysfunction, typically involving larger nerve fibres. There were no studies evaluating sensory function in women with fecal incontinence.

Conclusion

Current evidence suggests women with pelvic floor dysfunction demonstrate sensory impairment though the causes remain unclear. Further studies are needed to investigate the different conditions of pelvic floor dysfunction using standardized sensory testing techniques, as well as evaluate the timing and mechanism by which any sensory impairment develops. Neurourol. Urodynam. 36:550–556, 2017. © 2016 Wiley Periodicals, Inc.
Urethral bulking for recurrent stress urinary incontinence after midurethral sling failure
Authors: Zivanovic Irena , Rautenberg Oliver , Lobodasch Kurt , von Bünau Günther , Walser Claudia , Viereck Volker
Published: April 2016

Aims

To assess the effectiveness of a polyacrylamide hydrogel (PAHG; Bulkamid®) in treating recurrent stress urinary incontinence (SUI) following a previous midurethral sling (MUS) implant.

Methods

This observational study, conducted since 2009, included 60 patients with recurrent SUI or mixed urinary incontinence (MUI) after a previous MUS and who chose to be treated with PAHG. Objective and subjective outcomes were assessed at 1, 6, and 12 months after the initial injection. Patients were classified as cured based on a negative cough test (supine and standing) and <2 g urine on 1‐hr pad test and a VAS score improved by ≥90%. Improved were those with the loss of only a few drops of urine during the cough test and 2–10 g urine on 1‐hr pad test or a reduction >50% compared with preoperative urine loss and a VAS score improved by ≥75%.

Results

The volume of PAHG injected in the current study ranged from 1–3 ml. Cured/improved rates were 93.3% (56/60), 88.3% (53/60), and 83.6% (46/55) at 1, 6, and 12 months, respectively. Patients with MUI had a cured urgency urinary incontinence rate of 36.8%, 47.4%, and 38.9%, respectively. Voiding dysfunction rates were 13.3% (8/60), 8.3% (5/60), and 1.8% (1/55) at 1, 6, and 12 months and urinary tract infection rates were 5% (3/60), 11.7% (7/60), and 3.6% (2/55), respectively. Other adverse events were short‐term and/or observed in <4% of patients.

Conclusions

PAHG can be used to treat recurrent SUI after MUS failure with good outcome and low complication rates. Neurourol. Urodynam. 36:722–726, 2017. © 2016 The Authors. Neurourology and Urodynamics published by Wiley Periodicals, Inc.
Doubly Stochastic Sequential Assignment Problem
Authors: Khatibi Arash , Jacobson Sheldon H.
Published: April 2016

This article introduces the Doubly Stochastic Sequential Assignment Problem (DSSAP), an extension of the Sequential Stochastic Assignment Problem (SSAP), where sequentially arriving tasks are assigned to workers with random success rates. A given number of tasks arrive sequentially, each with a random value coming from a known distribution. On a task arrival, it must be assigned to one of the available workers, each with a random success rate coming from a known distribution. Optimal assignment policies are proposed for DSSAP under various assumptions on the random success rates. The optimal assignment algorithm for the general case of DSSAP, where workers have distinct success rate distribution, has an exponential running time. An approximation algorithm that achieves a fraction of the maximum total expected reward in a polynomial time is proposed. The results are illustrated by several numerical experiments. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 124–137, 2016
Feasibility of Pegylated Interferon in Children and Young Adults With Resected High‐Risk Melanoma
Authors: Navid Fariba , Herzog Cynthia E. , Sandoval John , Daryani Vinay M. , Stewart Clinton F. , Gattuso Jami , Mandrell Belinda , Phipps Sean , Chemaitilly Wassim , Sykes April , Davidoff Andrew M. , Shulkin Barry L. , Bahrami Armita , Furman Wayne L. , Mao Shenghua , Wu Jianrong , Schiff Deborah , Rao Bhaskar , Pappo Alberto
Published: April 2016

Background

Pegylated interferon α‐2b (IFN α‐2b) improves disease‐free survival in adults with resected stage III melanoma. We conducted a study to determine the feasibility and safety of incorporating pegylated IFN α‐2b as adjuvant therapy in the treatment of children and adolescents with high‐risk melanoma. Pharmacokinetic studies of IFN α‐2b and neuropsychological and quality of life (OL) assessments were performed.

Patient and Methods

Eligible patients with resected American Joint Committee on Cancer Stage IIC, IIIA, and IIIB cutaneous melanoma received nonpegylated IFN α‐2b 20 million units/m2/day intravenously 5 days per week for 4 weeks (induction) followed by pegylated IFN α‐2b 1 μg/kg/dose weekly subcutaneously (SQ) for 48 weeks (maintenance).

Results

Twenty‐three patients (15 females, median age 10 years) were enrolled. All patients completed induction therapy; five patients did not complete maintenance therapy either because of recurrent disease (n = 2) or toxicity (n = 3). The most common grade 3 and 4 toxicities of pegylated IFN α‐2b were neutropenia (35%) and elevated liver transaminases (17%). The median nonpegylated IFN α‐2b AUC0‐∞ (5,026 pcg⋅hr/ml) was similar to adults. The median pegylated IFN α‐2b exposure (48,480 pcg⋅hr/ml) was greater than the cumulative weekly exposure for nonpegylated IFN α‐2b administered SQ three times per week (TIW). Validated measures demonstrated an improvement in QOL scores and no decline in psychological functioning over the course of therapy.

Conclusions

Pegylated IFN α‐2b 1 μg/kg/dose SQ weekly as maintenance therapy in children and adolescents with high‐risk melanoma is feasible with tolerable toxicity and appears to yield higher exposures than nonpegylated IFN α‐2b administered SQ TIW.
A Phase 3, Randomized, Double‐Blind, Placebo‐Controlled Study to Determine the Effect of Romiplostim on Health‐Related Quality of Life in Children with Primary Immune Thrombocytopenia and Associated Burden in Their Parents
Authors: Mathias Susan D. , Li Xiaoyan , Eisen Melissa , Carpenter Nancy , Crosby Ross D. , Blanchette Victor S.
Published: April 2016

Background

Chronic immune thrombocytopenia (ITP) in children can negatively impact their health‐related quality of life (HRQoL) and impose a burden on their parents. This study sought to examine the effect of romiplostim on HRQoL and parental burden in children with primary ITP.

Procedure

This was a phase 3, randomized, double‐blind, placebo‐controlled study. Children aged <18 years with ITP ≥6 months were randomly assigned to receive romiplostim or placebo for 24 weeks. The Kids’ ITP Tool (KIT) was used to measure HRQoL and was administered to patients and/or their parents at baseline and weeks 8, 16, and 25. Mean KIT scores at each assessment and mean changes in KIT scores from baseline were calculated overall by treatment group and platelet response status. Psychometric properties of the KIT were evaluated and the minimally important difference (MID) was estimated for different KIT versions.

Results

Sixty‐two patients (42 romiplostim and 20 placebo) were enrolled. Changes in KIT scores by treatment group showed numerically greater and more often statistically significant improvements from baseline to each assessment for children receiving romiplostim versus placebo. Mixed‐effects analysis demonstrated statistically significantly greater reduction in parental burden from baseline in the romiplostim group versus placebo. Ranges for the MID were estimated as 9–13 points for the Child Self‐Report version and 11–13 points for the Parent Impact version.

Conclusions

The treatment with romiplostim may be associated with improved HRQoL in children with primary ITP and reduced burden to their parents.
Evaluation of sugar mill lime waste in biobased epoxy composites
Authors: Soydal Ulku , Esen Marti Mustafa , Kocaman Suheyla , Ahmetli Gulnare
Published: April 2016

In this study, precipitated calcium carbonate‐lime waste (LW) from sugar beet production was recycled as a raw material for the preparation of composite materials. Epoxidized soybean oil (ESO) was used as a co‐matrix in 50 wt% with bisphenol A‐type epoxy resin (ER). The composites were prepared with LW in varied per cent values (10 − 50 wt%) using the casting technique. The morphology of the composites was characterized by X‐ray diffraction and scanning electron microscopy. Effects of ESO and LW amounts on the mechanical and thermal properties of the composites were investigated. Modification with ESO remarkably enhanced the plasticity of the material, but decreased the curing degree about 2%. The modified ER shows about 13% increase in elongation at break over the pure epoxy matrix. Density and hardness of neat epoxy matrices were observed to increase with the LW content in the composite. Tensile strengths of all composites are higher than that obtained with neat epoxy. The thermogravimetric analyses show that ESO and LW significantly improve the thermal stability of neat ER at the temperatures above 300°C. The best thermal results were obtained with the composites containing 40‐ and 50 wt% LW. The residual weights of the composites are higher than that of neat ER and ER‐ESO, and increases with the increasing LW amount. The T5, T10 and T50 data of the composites are higher than those of neat ER and ER‐ESO. The water sorption values of the ER‐ESO matrix composites are in the range of 1.0 − 2.9 wt%. POLYM. COMPOS., 39:924–935, 2018. © 2016 Society of Plastics Engineers
Synthesis of single component element‐block materials based on siloxane‐based cage frameworks
Authors: Naka Kensuke , Irie Yasuyuki
Published: April 2016

This mini‐review focuses on recent efforts to prepare single component element‐block materials based on siloxane‐based cage frameworks, a promising approach to control the sequence of organic and inorganic segments in organic–inorganic hybrids at the molecular level. Polyhedral octasilsesquioxanes, denoted (RSiO1.5)8 or labeled T8 cages, and octadimethylsiloxy‐Q8 cages, denoted (RSiMe2OSiO1.5)8, are used here as siloxane‐based cage frameworks. Thermoplastic optically transparent silsesquioxane materials derived from a single cage compound can be obtained with dumbbell‐ and star‐shaped cage structures, allowing precise design of their structures for tuning properties. The siloxane‐based cage core dendrimers are ideal candidates for single component element‐block materials which possess three‐dimensional, well‐defined molecular level structures. Their rigid and cubic inorganic frameworks provide unique features for siloxane‐based cage core dendrimers. These topics attract attention in both academia and industry. © 2016 Society of Chemical Industry
Amine‐modified poly(vinyl alcohol) as a novel surfactant to modulate size and surface charge of poly(lactide‐co‐glycolide) nanoparticles
Authors: Cella Claudia , Martello Federico , Ghisletti Serena , Lenardi Cristina , Milani Paolo , Argentiere Simona
Published: April 2016

Poly(lactide‐co‐glycolide) (PLGA) nanoparticles (NPs) represent a promising tool for effective delivery of biomacromolecules, thanks to their biodegradability and biocompatibility properties. PLGA NPs are often synthesized by the emulsion‐solvent evaporation method and poly(vinyl alcohol) (PVA) represents one of the most commonly used surfactants. Although PVA‐mediated synthesis of PLGA NPs is effective in tailoring NP size and stability, the resulting negative surface charge can prevent both endosomal escape and biomacromolecule release in cell cytosol. To overcome this limit, a novel amino‐modified PVA (amino‐PVA) surfactant with a cationic charge was synthesized and its potential for the formulation of PLGA NPs was investigated. In either single (oil‐in‐water) or double (water‐in‐oil‐in‐water) emulsion synthesis, different mixtures of PVA and amino‐PVA were studied, by monitoring their effects on NP size and surface charge. Optimized properties were obtained with a combination of 0.975% (w/v) of PVA with 0.025% (w/v) of amino‐PVA. This formulation was further investigated for degradation properties and cytocompatibility. High stability and low cytotoxicity make the system promising for the encapsulation and release of hydrophilic drugs and biomacromolecules. © 2016 Society of Chemical Industry
Disorder transitions and conformational diversity cooperatively modulate biological function in proteins
Authors: Zea Diego Javier , Monzon Alexander Miguel , Gonzalez Claudia , Fornasari María Silvina , Tosatto Silvio C. E. , Parisi Gustavo
Published: April 2016

Structural differences between conformers sustain protein biological function. Here, we studied in a large dataset of 745 intrinsically disordered proteins, how ordered‐disordered transitions modulate structural differences between conformers as derived from crystallographic data. We found that almost 50% of the proteins studied show no transitions and have low conformational diversity while the rest show transitions and a higher conformational diversity. In this last subset, 60% of the proteins become more ordered after ligand binding, while 40% more disordered. As protein conformational diversity is inherently connected with protein function our analysis suggests differences in structure‐function relationships related to order‐disorder transitions.
Surface shapes and surrounding environment analysis of single‐ and double‐stranded DNA‐binding proteins in protein‐DNA interface
Authors: Wang Wei , Liu Juan , Sun Lin
Published: April 2016

Protein‐DNA bindings are critical to many biological processes. However, the structural mechanisms underlying these interactions are not fully understood. Here, we analyzed the residues shape (peak, flat, or valley) and the surrounding environment of double‐stranded DNA‐binding proteins (DSBs) and single‐stranded DNA‐binding proteins (SSBs) in protein‐DNA interfaces. In the results, we found that the interface shapes, hydrogen bonds, and the surrounding environment present significant differences between the two kinds of proteins. Built on the investigation results, we constructed a random forest (RF) classifier to distinguish DSBs and SSBs with satisfying performance. In conclusion, we present a novel methodology to characterize protein interfaces, which will deepen our understanding of the specificity of proteins binding to ssDNA (single‐stranded DNA) or dsDNA (double‐stranded DNA). Proteins 2016; 84:979–989. © 2016 Wiley Periodicals, Inc.
Film dissolution kinetics of aluminium at precisely adjusted pH‐values
Authors: Walkner Sarah , Hafner Martina , Hassel Achim Walter
Published: April 2016

This work focuses on the corrosion of aluminium in alkaline solution particularly at pH 11.0. The pH value plays a key role in corrosion processes. In a certain pH range, either the metal dissolves or protective films may be formed. For performing electrochemical measurements at a precisely adjusted pH value a setup, the so called ‘impedance titrator’ is used, that allows adjusting and controlling of pH value very precisely, while characterising the film properties. Electrochemical impedance spectroscopy is performed to investigate the formation of corrosion products. By keeping the pH at a constant value and simultaneously offering the system a constant hydroxide concentration, film formation takes place under defined conditions and a full kinetic characterisation becomes possible. This special system is required as the behaviour of aluminium in alkaline solution is quite complex and a various number of competing reactions like oxide film formation and dissolution occur.
Q‐factor study of nanomechanical system “metal tip – carbon nanowhisker” at low and ambient pressure
Authors: Lukashenko S. Y. , Mukhin I. S. , Veniaminov A. V. , Sapozhnikov I. D. , Lysak V. V. , Golubok A. O.
Published: April 2016

Nanomechanical oscillators based on amorphous carbon whiskers, localized on the top of tungsten tip were fabricated and investigated. The whiskers were grown in the scanning electron microscope chamber using focused electron beam technique. Oscillation trajectories and amplitude‐frequency characteristic of the oscillator were visualized at low and ambient pressure using a scanning electron microscope and a confocal laser‐scanning microscope, respectively. We experimentally show that at ambient pressure, the resonant frequency decreases significantly but the Q‐factor of the oscillator unexpectedly increases with respect to experimental data acquired at low pressure. The explanation was provided taking into account the role of thin water layer absorbed on the whisker from atmosphere. The model of the coupled oscillators is considered.
Mobility of a supported lipid bilayer on dispersed single‐walled carbon nanotubes
Authors: Posseckardt Juliane , Zhang Jiawei , Mertig Michael
Published: April 2016

The mobility of lipid bilayers supported on single‐walled carbon nanotube (SWCNT) networks on mica has been investigated by fluorescence recovery after photobleaching (FRAP). The carbon nanotubes have been dispersed by two different bile salt derivatives (sodium taurodeoxycholate (TDOC) and sodium cholate (SC)) as well as by single‐stranded deoxyribonucleic acid (ssDNA) oligonucleotides. Whereas the diffusion coefficient of the supported lipid bilayer (SLB) is not influenced by TDOC‐dispersed SWCNTs, for SC‐ and ssDNA‐dispersed SWCNTs, it is reduced and becomes SWCNT concentration dependent. Scanning force microscopy (SFM) measurements reveal that the lipid bilayer is not affected, when spanning over TDOC‐dispersed SWCNTs, whereas SC‐ and ssDNA‐dispersed SWCNTs are only bridged by a lipid monolayer acting as diffusion barrier. The effect is more pronounced for ssDNA‐dispersed SWCNTs.

Schematic viewgraph of lipid bilayer supported on a SWCNT network on mica.
Spatial interpolation of experimental raindrop size distribution spectra
Authors: Raupach Timothy H. , Berne Alexis
Published: April 2016

We present a new approach for spatial interpolation of experimental raindrop size distribution (DSD) spectra. The DSD is fundamental to the study and understanding of precipitation and its monitoring and modelling. It is measured insitu using disdrometers at point locations. Disdrometers provide a (non‐parametric) DSD spectrum in which drop concentrations are provided per class of drop diameter. Our approach uses geostatistics to estimate the same non‐parametric DSD at unmeasured locations. Non‐stationarity due to intermittency is taken into account through estimation of the dry drift of drop concentrations, using a rain occurrence field. Principal component analysis is used to express the DSD spectra in terms of uncorrelated components that can be interpolated independently at a requested point. These interpolated components can then be recombined into the full DSD. Estimation uncertainty for the interpolated DSD spectra is provided. Because all bulk rainfall variables can be calculated from the DSD and the entire DSD is estimated, the technique effectively interpolates all bulk variables at once. Leave‐one‐out testing shows that the technique estimates the DSD with minimal bias, and it is shown that the technique can be easily adapted to perform stochastic simulation of the non‐parametric DSD.
Bayesian estimation of the observation‐error covariance matrix in ensemble‐based filters
Authors: Ueno Genta , Nakamura Nagatomo
Published: April 2016

We develop a Bayesian technique for estimating the parameters in the observation‐noise covariance matrix Rt for ensemble data assimilation. We design a posterior distribution by using the ensemble‐approximated likelihood and a Wishart prior distribution and present an iterative algorithm for parameter estimation. The temporal smoothness of Rt can be controlled by an adequate choice of two parameters of the prior distribution, the covariance matrix S and the number of degrees of freedom ν. The ν parameter can be estimated by maximizing the marginal likelihood. The present formalism can handle cases in which the number of data points or data positions varies with time, the former of which is exemplified in the experiments. We present an application to a coupled atmosphere–ocean model under each of the following assumptions: Rt is a scalar multiple of a fixed matrix (Rt=αtΣ, where αt is the scalar parameter and Σ is the fixed matrix), Rt is diagonal, Rt has fixed eigenvectors or Rt has no specific structure. We verify that the proposed algorithm works well and that only a limited number of iterations are necessary. When Rt has one of the structures mentioned above, by assuming S to be the previous estimate we obtain a Bayesian estimate of Rt that varies smoothly in time compared with the maximum‐likelihood estimate. When Rt has no specific structure, we need to regularize S to maintain the positive‐definiteness. Through twin experiments, we find that the best estimate of Rt is, in general, obtained by a combination of structure‐free Rt and tapered S using decorrelation lengths of half the size of the model ocean basin. From experiments using real observations, we find that the estimates of the structured Rt lead to overfitting of the data compared with the structure‐free Rt.
The efficiency of diabatic heating and tropical cyclone intensification
Authors: Smith Roger K. , Montgomery Michael T.
Published: April 2016

Widely held arguments attributing the increasingly rapid intensification of tropical cyclones to the increasing ‘efficiency’ of diabatic heating in the cyclone's inner core region associated with deep convection are examined. The efficiency, in essence the amount of temperature warming compared with the amount of latent heat released, is argued to increase as the vortex strengthens on account of the strengthening inertial stability. Another aspect of the efficiency ideas concerns the location of the heating in relation to the radius of maximum tangential wind speed, with heating inside this radius seen to be more efficient in rapidly developing a warm‐core thermal structure and, presumably, a rapid increase in the tangential wind.

A more direct interpretation of the increased spin‐up rate is offered when the diabatic heating is located inside the radius of maximum tangential wind speed. Further, we draw attention to the limitations of assuming a fixed diabatic heating rate as the vortex intensifies and offer reasons, on these grounds alone, as to why it is questionable to apply the efficiency argument to interpret the results of observations or numerical model simulations of tropical cyclones. Moreover, since the spin‐up of the maximum tangential winds in a tropical cyclone takes place in the boundary layer and the spin‐up of the eyewall is a result of the vertical advection of high angular momentum from the boundary layer, it is questionable also whether deductions about efficiency in theories that neglect the boundary‐layer dynamics and thermodynamics are relevant to reality.