bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating sustainable biomass harvesting level for charcoal production to promote degraded woodlands recovery: A case study from Mutomo District, Kenya
Authors: Ndegwa Geoffrey M. , Nehren Udo , Anhuf Dieter , Iiyama Miyuki
Published: March 2018

Charcoal is an important urban fuel; however, when production is unregulated, it is a major cause of land and forest degradation. Production through selective harvesting of the preferred large, hardwood tree species leads to a degraded residual forest or woodland composed of juvenile hardwood trees and unused softwood tree species. This situation can be addressed by ensuring that the rate of preferred tree species extraction does not exceed the mean annual increment. This study estimated the sustainable rate of tree harvesting for charcoal in Mutomo District, based on field data collected between December 2012 and January 2013, through a forest inventory. The woodlands are subjected to selective logging for charcoal production, an activity undertaken by about half of the residents for their livelihood. The study findings show that charcoal production through selective logging has led to a reduction of the hardwood trees biomass density to 3.8 t ha−1 compared with an estimated desirable level of 12.5 t ha−1. The results also show that it would take between 25 and 31 years for the woodlands to recover to the desirable stocking level if harvesting was completely stopped. This duration would increase to between 54 and 64 years if 80% of the mean annual increment was harvested for charcoal production and 20% was retained for woodlands recovery. As the residents of Mutomo District are poor and highly dependent on charcoal production for their livelihood, a harvesting plan based on the latter option would set the woodlands on the path to recovery and ensuring a sustainable livelihood source.
Defining the low‐risk salvage laryngectomy—A single‐center retrospective analysis of pharyngocutaneous fistula
Authors: Vasani Sarju S. , Youssef Daniel , Lin Charles , Wellham Annabelle , Hodge Robert
Published: March 2018

Objectives

Salvage total laryngectomies (STL) are not a homogeneous group. Most will fall into two groups: i) Patients with previous AJCC stage I/II larynx cancer who have had radiotherapy to the larynx only (STL‐LOR), or ii) Patients who have had previous AJCC stage III/IV larynx cancer and subsequent radiotherapy to the larynx and draining nodal basins with concurrent cisplatin chemotherapy (STL‐CRT). We aimed to compare PCF rates following STL in these two groups.

Methods

A retrospective review of the department's cohort between January 2010 and August 2015 was conducted.

Results

Seventy‐seven patients underwent total laryngectomy for larynx cancer between January 2010 and August 2015. There were 10 post‐laryngectomy fistulas (13.0%). Three of these occurred in the 38 patients undergoing primary total laryngectomy (PTL), and seven in the 39 patients undergoing STL, rates of 7.9% and 17.9%, respectively. Twenty‐two patients had received radiation to the larynx alone without chemotherapy (STL‐LOR) for initial Stage I/II disease. Eleven patients had received laryngeal and neck irradiation plus cisplatin chemotherapy (STL‐CRT) for initial stage III/IV disease. Of the 22 STL‐LOR patients, two developed PCF (9.1%). Of the 11 STL‐CRT patients, five developed PCF. There was no difference in the rate of PCF between PTL and STL‐LOR. There was a statistically significant increase in PCF in STL‐CRT versus PTL (p = .009) and in PCF in STL‐CRT versus STL‐LOR (p = .027).

Conclusion

Salvage laryngectomies are often treated as a homogenous group. We demonstrate that PCF rates vary significantly depending on preoperative radiation fields and the use of chemotherapy.

Level of Evidence

2b.
The endoscopic modified lothrop procedure: Review of single institution experience and long‐term outcomes
Authors: Shen Jasper , Chan Nadia , Wrobel Bozena B.
Published: March 2018

Background

Endoscopic Modified Lothrop Procedure (EMLP) has become a fundamental practice in rhinology. Improvements in symptom burden, ostial patency, morbidity, and costs have surpassed that of an open approach to the frontal sinus. Long‐term efficacy has not been well established.

Objective

This study details the long‐term outcomes of EMLP and risk factors for subsequent surgical revision at a single institution.

Methods

This study utilized a retrospective review of patients who underwent EMLP from September 2006 to February 2017 by a single surgeon at an academic tertiary referral center. Patient demographics, indications, symptom burden, and endoscopic assessment of frontal ostium patency were analyzed for their effect on surgical outcome. Risk factors for failures were identified.

Results

Seventy‐six consecutive patients with an average age of 58.1 years met the inclusion and exclusion criteria and underwent EMLP for chronic rhinosinusitis (CRS, 59%), neoplasm (26%), and mucoceles (15%). The average number of standard endoscopic sinus surgeries prior to EMLP was 2.9. The mean follow‐up of the cohort was 34.8 months, at the end of which, EMLP was successful in 78% of all patients, requiring no further surgery. Ninety percent of patients reported significant clinical improvement at the most recent follow‐up. Subgroup analysis of CRS patients revealed an equally high success rate but a higher likelihood of ostial closure. Recurrent disease necessitated revision endoscopic surgery in 17 patients, the majority of whom suffered CRS. Only tissue eosinophilia was identified to significantly increase the risk of revision surgery.

Conclusions

The majority of the patients who undergo EMLP achieve sustained patency of the frontal sinus outflow tract and adequate symptom improvement. Prominent tissue eosinophilia identifies patients at risk of requiring additional frontal sinus surgery.

Level of Evidence

4.
Enhanced Photoluminescence of Mesostructured Organosilica Films with a High Density of Fluorescent Chromophores
Authors: Mizoshita Norihiro , Inagaki Shinji
Published: March 2018

Synthesis of mesostructured materials containing a high density of organic chromophores in the frameworks is highly desired for applications in unique optical devices using energy transfer. However, a dense accumulation of fluorescent chromophores in solid form generally causes concentration quenching. In this study, dense embedding of the chromophore 1,6‐diphenylpyrene within the framework of mesostructured organosilica films results in efficient blue fluorescence emission with high quantum yields of over 0.75. In contrast to conventional fluorescent films where chromophores are diluted and isolated to suppress concentration quenching, increasing the density of 1,6‐diphenylpyrene moieties within the mesostructured framework leads to the efficient formation of highly emissive excimers. Mesostructured frameworks achieving both high light‐absorptivity and efficient fluorescence emission have great potential in light‐emitting materials, fluorescence sensors, and light‐harvesting components for photoluminescent and photocatalytic systems.
Enzyme‐PISA: An Efficient Method for Preparing Well‐Defined Polymer Nano‐Objects under Mild Conditions
Authors: Tan Jianbo , Xu Qin , Li Xueliang , He Jun , Zhang Yuxuan , Dai Xiaocong , Yu Liangliang , Zeng Ruiming , Zhang Li
Published: March 2018

Enzyme catalysis is a mild, efficient, and selective technique that has many applications in organic synthesis as well as polymer synthesis. Here, a novel enzyme‐catalysis‐induced reversible addition‐fragmentation chain transfer (RAFT)‐mediated dispersion polymerization for preparing AB diblock copolymer nano‐objects with complex morphologies at room temperature is described. Taking advantage of the room‐temperature feature, it is shown that pure, worm‐like polymer nano‐objects can be readily prepared by just monitoring the viscosity. Moreover, it is demonstrated that inorganic nanoparticles and proteins can be loaded in situ into vesicles by this method. Finally, a novel oxygen‐tolerant RAFT‐mediated dispersion polymerization initiated by enzyme cascade reaction that can be carried out in open vessels is developed. The enzyme‐initiated RAFT dispersion polymerization provides a facile platform for the synthesis of various functional polymer nano‐objects under mild conditions.
Mycobiota of maize seeds revealed by rDNA‐ITS sequence analysis of samples with varying storage times
Authors: Xing Hui‐Qin , Ma Jian‐Cang , Xu Bing‐Liang , Zhang Shu‐Wu , Wang Jin , Cao Li , Yang Xue‐Mei
Published: March 2018

Fungi are an integral component of the plant microbiome. However, the composition and variation in the fungal communities (mycobiota) associated with seeds are poorly understood. In this study, we investigated the mycobiota of 11 maize seed samples with storage times ranging from 6 months to 12 years. Mycobiota were characterized by a culture‐based approach, and fungal species were identified through rDNA‐ITS sequence analyses. From a total of 169 pure fungal isolates obtained from both the seed surface and internal tissues, we identified 16 distinct species (belonging to 10 genera) associated with maize seeds, all but one of which were ascomycetes. Among these species, seven were exclusively isolated from internal tissues, two species were isolated only from the seed surface, and another six species were isolated from both the surface and internal tissues. Aspergillus niger was consistently found under all storage conditions and dominated fungal communities with a relative abundance of 36%–100%. Species of Fusarium (9%–40%) and Penicillium (9%–20%) were also frequently isolated, but other species appeared sporadically and were isolated from fewer than three seed stocks. According to our results, while the overall incidence of fungal infection generally declined with storage time, there was no consistent association between seed storage time and fungal species richness or relative abundance; furthermore, the composition of the mycobiota associated with maize seeds was highly variable among the samples. The detection of the four major mycotoxigenic fungal genera, specifically Aspergillus, Fusarium, Penicillium, and Alternaria, was alarming, and the isolation of a potential controlling agent as well as information about their temporal occurrence will contribute to the management of mycotoxins in the future.
Pseudopod‐associated protein KIF20B promotes Gli1‐induced epithelial‐mesenchymal transition modulated by pseudopodial actin dynamic in human colorectal cancer
Authors: Lin Wen‐Feng , Lin Xiao‐Lu , Fu Seng‐Wang , Yang Li , Tang Chao‐Tao , Gao Yun‐Jie , Chen Hao‐Yan , Ge Zhi‐Zheng
Published: March 2018

Kinesin family member 20B (KIF20B) has been reported to have an oncogenic role in bladder and hepatocellular cancer cells, but its role in colorectal cancer (CRC) progression remains unclear. In this study, we assessed the mRNA and protein levels of KIF20B in CRC tissues using qRT‐PCR and immunohistochemistry, respectively. KIF20B was overexpressed in CRC tissues and was associated with cancer invasion and metastasis. Mechanistically, KIF20B overexpression promoted the epithelial‐mesenchymal transition (EMT) process mediated by glioma‐associated oncogene 1 (Gli1) as well as CRC cell migration and invasion. Interestingly, KIF20B was localized in pseudopod protrusions of CRC cells and influenced the formation of cell protrusions, especially the EMT‐related invadopodia. Moreover, intracellular actin dynamic participated in the modulation of the Gli1‐mediated EMT and EMT‐related cell pseudopod protrusion formation induced by KIF20B. We identified a role for KIF20B in CRC progression and revealed a correlation between KIF20B expression in CRC tissues and patient prognosis. The underlying mechanism was associated with the Gli1‐mediated EMT and EMT‐related cell protrusion formation modulated by intracellular actin dynamic. Thus, KIF20B may be a potential biomarker and promising treatment target for CRC.
Molecular changes in the absence of severe pathology in the pulvinar in dementia with Lewy bodies
Authors: Erskine Daniel , Ding Jinhui , Thomas Alan J. , Kaganovich Alice , Khundakar Ahmad A. , Hanson Peter S. , Taylor John‐Paul , McKeith Ian G. , Attems Johannes , Cookson Mark R. , Morris Christopher M.
Published: March 2018

Background: Dementia with Lewy bodies is characterized by transient clinical features, including fluctuating cognition and visual hallucinations, implicating dysfunction of cerebral hub regions, such as the pulvinar nuclei of the thalamus. However, the pulvinar is typically only mildly affected by Lewy body pathology in dementia with Lewy bodies, suggesting additional factors may account for its proposed dysfunction.

Methods: We conducted a comprehensive analysis of postmortem pulvinar tissue using whole‐transcriptome RNA sequencing, protein expression analysis, and histological evaluation.

Results: We identified 321 transcripts as significantly different between dementia with Lewy bodies cases and neurologically normal controls, with gene ontology pathway analysis suggesting the enrichment of transcripts related to synapses and positive regulation of immune functioning. At the protein level, proteins related to synaptic efficiency were decreased, and general synaptic markers remained intact. Analysis of glial subpopulations revealed astrogliosis without activated microglia, which was associated with synaptic changes but not neurodegenerative pathology.

Discussion: These results indicate that the pulvinar, a region with relatively low Lewy body pathological burden, manifests changes at the molecular level that differ from previous reports in a more severely affected region. We speculate that these alterations result from neurodegenerative changes in regions connected to the pulvinar and likely contribute to a variety of cognitive changes resulting from decreased cortical synchrony in dementia with Lewy bodies. © 2018 International Parkinson and Movement Disorder Society
A rapid and reliable chromosome analysis method for products of conception using interphase nuclei
Authors: Babu Ramesh , Van Dyke Daniel L. , Bhattacharya Saurabh , Dev Vaithilingam G. , Liu Mingya , Kwon Minjae , Gu Guangyu , Koduru Prasad , Rao Nagesh , Williamson Cynthia , Fuentes Ernesto , Fuentes Sarah , Papa Stephen , Kopuri Srikanthi , Lal Vandana
Published: March 2018

Background

Karyotype determination has a central role in the genetic workup of pregnancy loss, as aneuploidy (trisomy and monosomy) and polyploidy (triploidy and tetraploidy) are the cause in at least 50% of first trimester, 25% of second trimester, and 11% of third trimester miscarriages. There are several limitations with the current approaches of obtaining a karyotype using traditional cytogenetics, fluorescence in situ hybridization with a limited number of probes, and chromosomal microarray. These include culture failure, incomplete results, lower sensitivity, and longer reporting time.

Methods

To overcome current limitations, a novel molecular assay is developed with a Standard Resolution Interphase Chromosome Profiling probe set which is a variation of the recently developed High Resolution probe set. It generates a molecular karyotype that can detect all major changes commonly associated with pregnancy loss. Initial familiarization of signal patterns from the probe set was used, followed by validation of the method using 83 samples from miscarriages in a blind study from three different laboratories. Finally, the clinical utility of the method was tested on 291 clinical samples in two commercial reference laboratory settings on two different continents.

Results

The new molecular approach not only identified all the chromosome changes observed by current methods, but also significantly improved abnormality detection by characterizing derivative chromosomes and finding subtle subtelomeric rearrangements, balanced and unbalanced. All Robertsonian translocations were also detected. The abnormality rate was 54% on clinical samples from commercial laboratory 1 and 63% from laboratory 2.

Conclusion

The attributes of this method make it an ideal choice for the genetic workup of miscarriages, namely (1) near 100% successful results, (2) greater sensitivity than conventional chromosome analysis or FISH panels, (3) rapid reporting time, and (4) favorable comparisons with chromosomal microarray.
Toward clinical and molecular understanding of pathogenic variants in the ZBTB18 gene
Authors: van der Schoot Vyne , de Munnik Sonja , Venselaar Hanka , Elting Mariet , Mancini Grazia M. S. , Ravenswaaij‐Arts Conny M. A. , Anderlid Britt‐Marie , Brunner Han G. , Stevens Servi J. C.
Published: March 2018

Background

Patients with pathogenic variants in ZBTB18 present with Intellectual Disability (ID) with frequent co‐occurrence of corpus callosum (CC) anomalies, hypotonia, microcephaly, growth problems and variable facial dysmorphologies. These features illustrate a key role for ZBTB18 in brain development.

Methods

Patients with a pathogenic variant in ZBTB18 were detected by diagnostic whole exome sequencing (WES) performed in our center. We reviewed the literature and used GeneMatcher to include other cases. YASARA and WHAT IF were used to provide insight into the structural effect of missense variants located in the C2H2 zinc finger domains of the ZBTB18 protein.

Results

We give a complete overview of pathogenic variants in ZBTB18 detected to date, showing inconsistent presence of clinical features, including CC anomalies. We present four new cases with a de novo pathogenic variant in the ZBTB18 gene, including the fourth case in which a de novo p.Arg464His variant was found.

Conclusion

Homology modeling of protein structure points to a variable degree of impaired DNA binding caused by missense variants in these domains probably leading to Loss of Function (LoF). Putative partial LoF may present with a less distinctive phenotype than complete LoF, as seen in truncating variants, which presents with an extensive variability in the phenotypic spectrum. Our data do not support a clear genotype to phenotype correlation.
Numerical algorithms for approximation of fractional integral operators based on quadratic interpolation
Authors: Blaszczyk Tomasz , Siedlecki Jaroslaw , Ciesielski Mariusz
Published: March 2018

We present numerical algorithms calculating compositions of the left and right fractional integrals. We apply quadratic interpolation and obtain the fractional Simpson's rule. We estimate the local truncation error of the proposed approximations, calculate errors generated by presented algorithms, and determine the experimental rate of convergence. Finally, we show examples of numerical evaluation of these operators.
Forced oscillation of delay difference equations via nonprincipal solution
Authors: Özbekler Abdullah
Published: March 2018

In this paper, we obtain a new oscillation result for delay difference equations of the form

urn:x-wiley:mma:media:mma4843:mma4843-math-0001
under the assumption that corresponding homogenous equation

urn:x-wiley:mma:media:mma4843:mma4843-math-0002
is nonoscillatory, where τn≤n+1. It is observed that the oscillation behaviormay be altered due to presence of the delay. Extensions to forced Emden‐Fowler–type delay difference equations

urn:x-wiley:mma:media:mma4843:mma4843-math-0003
in the sublinear (0<α<1) and the superlinear (1<α) cases are also discussed.
Mediterranean Diet, Glucose Homeostasis, and Inflammasome Genetic Variants: The CORDIOPREV Study
Authors: Roncero‐Ramos Irene , Rangel‐Zuñiga Oriol A. , Lopez‐Moreno Javier , Alcala‐Diaz Juan F. , Perez‐Martinez Pablo , Jimenez‐Lucena Rosa , Castaño Justo P. , Roche Helen M. , Delgado‐Lista Javier , Ordovas Jose M. , Camargo Antonio , Lopez‐Miranda Jose
Published: March 2018

Scope

Insulin resistance (IR) and chronic low‐grade inflammation are hallmarks of type 2 diabetes mellitus (T2DM). The “NOD‐like receptor pyrin domain containing‐3” (NLRP3) inflammasome component of innate immunity is a metabolic stress sensor modulated by dietary and genetics factors. The aim of this study was to evaluate the effects of the consumption of two diets for 3 years, Mediterranean (Med) and low fat, on glucose homeostasis in the 1002 coronary heart disease patients of the CORDIOPREV study, according to a genetic variant of NLRP3 inflammasome.

Methods and results

The study was conducted in the framework of the CORDIOPREV study, a randomized dietary intervention with Med and low‐fat diets. Single nucleotide polymorphisms (SNPs) located at inflammasome NLRP3 gene were genotyped by OpenArray platform. Nondiabetic CT+TT carriers of the rs4612666 SNP and AG+AA carriers of the rs10733113 SNP increased insulin sensitivity index (ISI) after 3 years of dietary intervention, whereas no effect was observed in diabetic patients. Further analysis by diet showed that the improvement of the ISI in nondiabetic rs10733113 AG+AA carriers was specific to the consumption of the Med diet.

Conclusion

Our results show that the benefits associated with a Med diet regarding glucose homeostasis in non‐T2DM patients depend on genetic variation in the inflammasome.
Experimental validation of absolute SPECT/CT quantification for response monitoring in breast cancer
Authors: Collarino Angela , Pereira Arias‐Bouda Lenka M. , Valdés Olmos Renato A. , van der Tol Pieternel , Dibbets‐Schneider Petra , de Geus‐Oei Lioe‐Fee , van Velden Floris H. P.
Published: March 2018

Purpose

Recent developments in iterative image reconstruction enable absolute quantification of SPECT/CT studies by incorporating compensation for collimator–detector response, attenuation, and scatter as well as resolution recovery into the reconstruction process (Evolution; Q.Metrix package; GE Healthcare, Little Chalfont, UK). The aim of this experimental study is to assess its quantitative accuracy for potential clinical 99mTc‐sestamibi (MIBI)‐related SPECT/CT application in neoadjuvant chemotherapy response studies in breast cancer.

Methods

Two phantoms were filled with MIBI and acquired on a SPECT/CT gamma camera (Discovery 670 Pro; GE Healthcare), that is, a water cylinder and a NEMA body phantom containing six spheres that were filled with an activity concentration reflecting clinical MIBI uptake. Subsequently, volumes‐of‐interest (VOI) of each sphere were drawn (semi)automatically on SPECT using various isocontour methods or manually on CT. Finally, prone MIBI SPECT/CT scans were acquired 5 and 90 min p.i. in a locally advanced breast cancer patient.

Results

Activity concentration in the four largest spheres converged after nine iterations of evolution. Depending on the count statistics, the accuracy of the reconstructed activity concentration varied between −4.7 and −0.16% (VOI covering the entire phantom) and from 6.9% to 10% (8.8 cm ⌀ cylinder VOI placed in the center of the phantom). Recovery coefficients of SUVmax were 1.89 ± 0.18, 1.76 ± 0.17, 2.00 ± 0.38, 1.89 ± 0.35, and 0.90 ± 0.26 for spheres with 37, 28, 22, 17, and 13 mm ⌀, respectively. Recovery coefficients of SUVmean were 1.07 ± 0.06, 1.03 ± 0.09, 1.17 ± 0.21, 1.10 ± 0.20, and 0.52 ± 0.14 (42% isocontour); 1.10 ± 0.07, 1.02 ± 0.09, 1.13 ± 0.19, 1.06 ± 0.19, and 0.51 ± 0.13 (36% isocontour with local background correction); and 0.96, 1.09, 1.03, 1.03, and 0.29 (CT). Patient study results were concordant with the phantom validation.

Conclusions

Absolute SPECT/CT quantification of breast studies using MIBI seems feasible (<17% deviation) when a 42% isocontour is used for delineation for tumors of at least 17 mm diameter. However, with tumor shrinkage, response evaluation should be handled with caution, especially when using SUVmax.
Machine learning RF shimming: Prediction by iteratively projected ridge regression
Authors: Ianni Julianna D. , Cao Zhipeng , Grissom William A.
Published: March 2018

Purpose

To obviate online slice‐by‐slice RF shim optimization and reduce
mapping requirements for patient‐specific RF shimming in high‐field magnetic resonance imaging.

Theory and Methods

RF Shim Prediction by Iteratively Projected Ridge Regression (PIPRR) predicts patient‐specific, SAR‐efficient RF shims with a machine learning approach that merges learning with training shim design. To evaluate it, a set of
maps was simulated for 100 human heads for a 24‐element coil at 7T. Features were derived from tissue masks and the DC Fourier coefficients of the coils’
maps in each slice, which were used for kernelized ridge regression prediction of SAR‐efficient RF shim weights. Predicted shims were compared to directly designed shims, circularly polarized mode, and nearest‐neighbor shims predicted using the same features.

Results

PIPRR predictions had 87% and 13% lower
coefficients of variation compared to circularly polarized mode and nearest‐neighbor shims, respectively, and achieved homogeneity and SAR similar to that of directly designed shims. Predictions were calculated in 4.92 ms on average.

Conclusion

PIPRR predicted uniform, SAR‐efficient RF shims, and could save a large amount of
mapping and computation time in RF‐shimmed ultra‐high field magnetic resonance imaging.
Fibromyalgia syndrome and small fiber, early or mild sensory polyneuropathy
Authors: Lawson Victoria H. , Grewal Jessie , Hackshaw Kevin V. , Mongiovi Phillip C. , Stino Amro M.
Published: March 2018

Introduction: Pain mechanisms in fibromyalgia syndrome (FMS) are not clearly understood. Growing evidence appears to suggest a role for small fiber polyneuropathy (SFPN) in some FMS patients, as measured by epidermal nerve fiber density (ENFD). We aimed to better characterize and distinguish the subset of patients with both fibromyalgia and small fiber, early or mild sensory polyneuropathy (FM‐SFSPN). Methods: 155 FMS patients with neuropathic symptoms completed a Short Form McGill Questionnaire and visual analog scale in addition to having skin biopsies, nerve conduction studies (NCS), and serologic testing. Results: Sural and medial plantar (MP) response amplitudes correlated with ENFD, with markers of metabolic syndrome being more prevalent in this subset of patients. Pain intensity and quality did not distinguish patients. Discussion: The FM‐SFSPN subset of patients may be identified through sural and MP sensory NCS and/or skin biopsy but cannot be identified by pain features and intensity. Muscle Nerve 58: 625–630, 2018
Correlation between electromyography and perineometry in evaluating pelvic floor muscle function in nulligravidas: A cross‐sectional study
Authors: Macêdo Lorena C. , Lemos Andrea , A. Vasconcelos Danilo , Katz Leila , Amorim Melania M.R.
Published: March 2018

Objective

To correlate the results of electromyography and perineometry in the assessment of PFM function in nulligravidas.

Methods

The cross‐sectional observational study was approved by the internal review board of the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP) and was conducted in the Instituto Paraibano de Pesquisa Professor Joaquim Amorim Neto (IPESQ). Thirty‐eight nulligravidas aged 18‐39 years of age, who had already initiated their sexual life, participated in the study. Exclusion criteria consisted of the presence of genital prolapse, a history of pelvic or urogenital surgery and the presence of neurological disease producing muscle disorders. For the evaluation procedure, the women were submitted to a clinical evaluation of the pelvic floor muscles followed by electromyography. Perineometry was performed 72 h later. Prior to electromyography and perineometry, the women were given standardized training with electromyographic biofeedback to teach them to contract only their pelvic floor muscles.

Results

A highly positive, statistically significant correlation (r = 0.968; P < 0.001) was found between the electromyographic and perineometric findings.

Conclusions

A strong correlation was found between perineometric and electromyographic findings of pelvic floor muscle function.
Place of surgery in the management of post‐operative chronic pain after placement of prosthetic material based on a series of 107 cases
Authors: Leonard Grégoire , Perrouin‐Verbe Marie‐Aimée , Levesque Amélie , Riant Thibault , Normand Loïc Le , Labat Jean‐Jacques , Rigaud Jérôme
Published: March 2018

Aims

The objective of this study was to evaluate the efficacy of surgical removal of prosthetic material, possibly combined with nerve release, on chronic postoperative pain following placement of prosthetic material.

Material and methods

Single‐tertiary‐centre study on 107 patients managed between November 2004 and April 2016 for removal of prosthetic material responsible for postoperative chronic pain: retropubic suburethral sling (n = 32), transobturator suburethral sling (n = 50), prolapse mesh (n = 16), and hernia mesh (n = 9). The primary endpoint was at least 50% reduction of pain evaluated by a pain numerical rating scale (NRS).

Results

The mean interval between the initial operation involving placement of prosthetic material and reoperation for removal of prosthetic material was 41.2 ± 35.4 months. In all cases pain apperaed immediately following prosthetic material placement surgery. Pain presented neuropathic features in almost 30% of cases and was poorly systematized in more than one‐half The mean follow‐up of the study population was 8.4 ± 10.3 months. The mean pain NRS score for the overall population was seven preoperatively and three at last follow‐up. At least 50% reduction of the pain NRS score was observed 67% of cases at last follow‐up. During follow‐up, 45% of patients experienced relapse of the disorder for which the prosthetic material was initially placed with, in particular, a 62% recurrence rate of urinary incontinence after removal of transobturator suburethral tape.

Conclusion

Surgical removal of prosthetic material to treat chronic postoperative pain, achieved global improvement of pain in about two‐thirds of cases, but with a risk of recurrence of the initial disorders.
Faster computation of successive bounds on the group betweenness centrality
Authors: Dinler Derya , Tural Mustafa Kemal
Published: March 2018

We propose a method that computes bounds on the group betweenness centrality (GBC) of groups of vertices of a network. Once certain quantities related to the network are computed in the preprocessing step that takes time, where n is the number of vertices in the network, our method can compute bounds on the GBC of any number of groups of vertices successively, for each group requiring a running time proportional to the square of its size. Our method is an improvement of the method of Kolaczyk et al. [Social Networks, 31, 3 (2009)], which has to be restarted for each group making it less efficient for the successive GBC computations. In addition, the bounds used in our method are stronger and/or faster to compute. Our computational experiments show that in the search for a group of a certain size with the highest GBC value, our method reduces the number of candidate groups substantially and in some cases the optimal group can be found without exactly computing the GBC values which is computationally more demanding.
Transient solutions to nonlinear acousto‐magneto‐mechanical coupling for axisymmetric MRI scanner design
Authors: Bagwell S. , Ledger P.D. , Gil A.J. , Mallett M.
Published: March 2018

In this work, we simulate the coupled physics describing a magnetic resonance imaging (MRI) scanner by using a higher‐order finite element discretisation and a Newton‐Raphson algorithm. To apply the latter, a linearisation of the nonlinear system of equations is necessary, and we consider two alternative approaches. In the first approach, ie, the nonlinear approach, there is no approximation from a physical standpoint, and the linearisation is performed about the current solution. In the second approach, ie, the linearised approach, we realise that the MRI problem can be described by small dynamic fluctuations about a dominant static solution and linearise about the latter. The linearised approach permits solutions in the frequency domain and provides a computationally efficient way to solve this challenging problem, as it allows the tangent stiffness matrix to be inverted independently of time or frequency. We focus on transient solutions to the coupled system of equations and address the following two important questions: (i) how good is the agreement between the computationally efficient linearised approach compared with the intensive nonlinear approach and (ii) over what range of MRI operating conditions can the linearised approach be expected to provide acceptable results for outputs of interest in an industrial context for MRI scanner design? We include a set of academic and industrially relevant examples to benchmark and illustrate our approach.
Material design of elastic structures using Voronoi cells
Authors: Podestá J. M. , Méndez C. G. , Toro S. , Huespe A. E. , Oliver J.
Published: March 2018

New tools for the design of metamaterials with periodic microarchitectures are presented. Initially, a two‐scale material design approach is adopted. At the structure scale, the material effective properties and their spatial distribution are obtained through a Free Material Optimization technique. At the microstructure scale, the material microarchitecture is designed by appealing to a Topology Optimization Problem (TOP). The TOP is based on the topological derivative and the level set function. The new proposed tools are used to facilitate the search of the optimal microarchitecture configuration. They consist of the following: (i) a procedure to choose an adequate shape of the unit cell domain where the TOP is formulated and shapes of Voronoi cells associated with Bravais lattices are adopted and (ii) a procedure to choose an initial material distribution within the Voronoi cell being utilized as the initial configuration for the iterative TOP.
A fast algorithm for multifield representation and multiscale simulation of high‐quality 3D stochastic aggregate microstructures by concurrent coupling of stationary Gaussian and fractional Brownian random fields
Authors: Huang Junjie , Peng Qi
Published: March 2018

This study presents a multiscale computational framework for the representation and generation of concrete aggregate microstructures on the basis of the multifield theory, which couples the stationary Gaussian random field with the fractional Brownian random field. Specifically, the stationary Gaussian field is utilized to simulate the morphological shape of an aggregate on the coarse scale, whereas the surface topography of the aggregate on the fine scale is represented by the fractional Brownian field. To bridge the 2 scales, a concurrent coupling formula is proposed. This coupled technique allows for smooth transition between the coarse and fine scales and permits the rapid generation of highly realistic concrete aggregates that can be tailored to the desired quality and requirements, making the algorithm computationally appealing. In the generation of the random fields on the 2 scales, the Fourier representation of block circulant covariance matrices with circulant blocks is exploited, which yields substantial efficiency advantages over the conventional Cholesky decomposition approach in factorizing covariance matrices as well as simulating random fields. Meanwhile, a microsurface postprocessing and reconstruction procedure is also developed to convert the generated random fields into realistic 3D shapes. The numerical methodology proposed in this study offers tremendous potential for a plethora of applications in cement‐based materials.
The morphological, mechanical, rheological, and thermal properties of PLA/PBAT blown films with chain extender
Authors: Li Xin , Ai Xue , Pan Hongwei , Yang Jia , Gao Guanghui , Zhang Huiliang , Yang Huili , Dong Lisong
Published: March 2018

Biodegradable poly(lactic acid) (PLA)/poly(butylene adipate‐co‐terephthalate) (PBAT) blends and films were prepared using melt blending and blowing films technique in the presence of chain extender‐Joncryl ADR 4370F. The ADR contains epoxy functional groups and used as a compatibilizer. The morphological, mechanical, rheological, thermal, and crystalline properties of the PLA/PBAT/ADR blown films were studied. Scanning electron microscopy micrographs of the films revealed more ductile deformation with increasing PBAT content. The addition of PBAT enhanced the toughness of the PLA film. Tensile tests indicated that the elongation at break increased from 20.5% to 334.6% in the machine direction and from 7.1% to 715.9% in the transverse direction. The Young modulus increased from 2690.5 to 395.6 MPa in the machine direction and from 2623.5 to 154.0 MPa in the transverse direction. The sealing strength of 40/60/0.15 PLA/PBAT/ADR film was the highest among all the samples up to 9.4 N 15 mm−1. These findings gave important implications for designing and manufacturing polymer packaging materials.
Microwave‐assisted synthesis of nanocomposites from polyimides chemically cross‐linked with functionalized carbon nanotubes for aerospace applications
Authors: Govindaraj Balasubramani , Sarojadevi Muthusamy
Published: March 2018

Polymer‐carbon nanotube nanocomposites are extensively investigated for microelectronics and aerospace applications. In this study, novel polyimide/f‐MWCNT nanocomposites made from 2,4‐bis(4‐aminophenylamido)‐6‐chloroquinazoline, pyromellitic dianhydride and functionalized‐Multi Walled Carbon Nanotubes (f‐MWCNT) by an efficient microwave assisted method were investigated. The structure of the prepared diamine monomer was confirmed by FT‐IR, 1H‐NMR, and 13C‐NMR spectral techniques. The prepared nanocomposites (Tg values from 338°C to 375°C) show improved thermal property as indicated by differential scanning calorimetry and thermogravimetric analysis. Polyimide/f‐MWCNT nanocomposites were found to have higher dielectric constant, and the limiting oxygen index values of prepared nanocomposites are in the range of 29.5 to 35.5, indicating a high flame retardancy. Additionally, the morphological studies were conducted by X‐ray diffraction and scanning electron microscopy. Overall, it is observed that chemically connected polyimide‐functionalized carbon nanotube nanocomposites could be used for aerospace and microelectronics applications that require high Tg, dielectric constant and high flame retardancy.
Novel synthesis of high‐molecular‐weight prepolymer of poly(p‐phenylene benzoxazole) in ionic liquids
Authors: Li Xianglong , Meng Linghui , Wu Yadong , Wang Fang , Huang Yudong
Published: March 2018

Using ionic liquids (ILs) as the reaction solvent for the synthesis of prepolymer polyamide of poly(p‐phenylene benzoxazole) (PBO) was investigated. The optimum condition of prepolymer preparation was determined in ILs. A series of 1,3‐dialkylimidazolium ILs were used to be the reaction media of the polycondensation. The relationship between the molecular weight of prepolymer and the structure of ILs was analysed by changing the structure of the cation and species of anion of ILs. In order to prove the feasibility of the transformation, the prepolymer was used to prepare PBO in polyphosphoric acid media, and the conversion process was analyzed. The spinnability of the PBO solution was explored by the preparation of PBO fibers. The basic mechanical properties of PBO single fiber were tested. In a word, using 1,3‐dialkylimidazolium ILs as the reaction solvents was feasible for the synthesis of high‐molecular‐weight PBO prepolymer, which could be a promising PBO preparation method.
A review on the mechanical, electrical and EMI shielding properties of carbon nanotubes and graphene reinforced polycarbonate nanocomposites
Authors: Bagotia Nisha , Choudhary Veena , Sharma D. K.
Published: March 2018

Recently, it has been found that carbon nanotubes (CNTs) and graphene could prove to be the most promising carbonaceous fillers in polymers nanocomposites field because of their better structural and functional properties. Their uniform dispersion in polymer matrix leads to significant improvements in their several properties. This paper reviews the effect of nanofillers, ie, CNTs, derivatized CNTs, and graphene on the polycarbonate nanocomposite and its application in aerospace, automobile, sports, electronic sectors, and various industries. The comparative analysis of carbon‐based fillers on the different properties of polycarbonate nanocomposites is also included.
New hybrid materials based on double‐functionalized linseed oil and halloysite
Authors: Balanuca Brindusa , Ghebaur Adi , Stan Raluca , Vuluga Dumitru Mircea , Vasile Eugeniu , Iovu Horia
Published: March 2018

A series of hybrid systems which combine double‐functionalized linseed oil (methacrylated epoxidized linseed oil) and 2 types of functionalized halloysite (methacrylated halloysite and epoxidized halloysite) was designed in the current study. The curing of the new formulated oil‐clay mixtures was performed via 2 different mechanisms under the influence of the temperature: free‐radical and anionic polymerization. The effect of the functionalized clay tubes against the oil‐based macromonomer reactivity, representing the focus of this study, was monitored by differential scanning calorimetry and Fourier transform infrared spectrometry, concluding that both types of halloysite nanotubes (HNTs) exhibit significant influence on the building of methacrylate/epoxy networks. The effect of the HNTs on the methacrylated epoxidized linseed oil network properties was studied by dynamic mechanical analysis and thermogravimetric analysis, and the morphology of the synthesized hybrids was investigated by scanning electron microscopy. The results suggested that the designed oil‐based hybrid performance is determined by the presence of the both HNT molecules.
Role, effect, and influences of micro and nano‐fillers on various properties of polymer matrix composites for microelectronics: A review
Authors: Nilagiri Balasubramanian Karthik Babu , Ramesh Thillaigovindan
Published: March 2018

Ever since the discovery of polymer composites, its potential has been anticipated for numerous applications in various fields such as microelectronics, automobiles, and industrial applications. In this paper, we review filler reinforced polymer composites for its enormous potential in microelectronic applications. The interface and compatibility between matrix and filler have a significant role in property alteration of a polymer nanocomposites. Ceramic reinforced polymeric nanocomposites are promising candidate dielectric materials for several micro‐ and nano‐electronic devices. Because of its synergistic effect like high thermal conductivity, low thermal expansion, and dielectric constant of ceramic fillers with the polymer matrix, the resultant nanocomposites have high dielectric breakdown strength. The thermal and dielectric properties are discussed in the view of filler alignment techniques and its effect on the composites. Furthermore, the effect of various surface modified filler materials in polymer matrix, concepts of network forming using filler, and benefits of filler alignment are also discussed in this work. As a whole, this review article addresses the overall view to novice researchers on various properties such as thermal and dielectric properties of polymer matrix composites and direction for future research to be carried out.
Multifaceted polymeric materials in three‐dimensional processing (3DP) technologies: Current progress and prospects
Authors: Oderinde Olayinka , Liu Shunli , Li Kewen , Kang Mengmeng , Imtiaz Hussain , Yao Fang , Fu Guodong
Published: March 2018

Three‐dimensional printing (3DP) technologies, which are sets of powerful deposition methods employed to fabricate 3D objects with materials in the fields of material sciences and engineering, biomedical and biocompatible structural components, automotive, aviation, and polymers, among others, are currently rapidly developing manufacturing technologies. The methods have significant advantages, which include designing flexibility, enhanced geometrical freedom, low cost, and net shape manufacture, among others, over the traditional “subtractive” method. This review highlights the major 3D printing techniques, especially in the fields of advanced polymeric material fabrication and engineering, as well as the synergy in the incorporation of different types of polymeric materials and composites in a process that will lead to an enhancement of dimensional accuracy for 3D technologies. Furthermore, composite ink systems especially polymer‐based and hydrogel‐based in tissue engineering applications are also discussed.
Nanocavitation in silica filled styrene‐butadiene rubber regulated by varying silica‐rubber interfacial bonding
Authors: Cao Xijuan , Zhou Xing , Weng Gengsheng
Published: March 2018

The influence of filler‐matrix interfacial bonding on the nanocavitation of rubber materials has not been explored clearly. We herein report the nanocavitation modes and geometrical features impacted by varying the silica‐styrene‐butadiene rubber interfacial bonding. The interfacial bonding is tuned by grafting different amount of multi‐functional silane coupling agents on to the silica nanoparticles. By using synchrotron radiation small angle X‐ray scattering measurements, 2 major classes of cavitation were detected. When the interfacial strength was weak, fibrillar nanocavitation, with lengths ranging from 120 to 217 nm and diameter of the same order of the particle size, was generated by interfacial decohesion at the particle pores along the stretching direction. After grafting modification, the fibril‐like nanocavitation almost disappears and nanocavitation content decreases first at lower grafting density; then nanocavitation content increases at higher grafting density, where nanocavitation in confined rubber regions dominates. It is finally proposed that nanoparticle interfacial strengthening can change the cavitation mode from interfacial decohesion to confined rubber matrix nanocavitation, which exhibits more favorable prevention of the macroscopic failure by cracking.
Preparation of urea formaldehyde microsphere and its effect on flame retardant ethylene vinyl acetate composites
Authors: Yu Guoxing , Liu Yinfeng , Li Juan
Published: March 2018

Urea formaldehyde microsphere (UFM) was prepared and used with organic montmorillonite (OMMT) to modify the flame retardant efficiency of ethylene vinyl acetate copolymer (EVA)/intumescent flame retardant (IFR) composites. The results show that single IFR may modify the flame retardancy of EVA, but its efficiency is not good enough. The EVA composite containing 21 wt% IFR is just classified the UL_94 V2 and has a limiting oxygen index (LOI) 24.7 vol%. Combining UFM with IFR does not improve the flame retardancy of EVA/IFR composites, and blending OMMT with IFR only improves its LOI. Adding 2 wt% UFM, 2 wt% OMMT, and 17 wt% IFR into EVA, it obtains the UL_94 V0 without melt dripping and a LOI 29.0 vol%. Also, the peak heat release rate and total heat release decrease a lot. Good synergistic effects among IFR, UFM, and OMMT improve the char residues and modify the char micromorphology of EVA composites, which provide better protect for the underlying resin.