bluuebunny/crossref_metadata_2025 huggingface dataset:
Determine factors contributing to vulnerability of fishermen to these disasters
Authors: AMORE DR JOY ATIENO
Published: October 2024

Natural and technological hazards are common occurrences facing the fishing community throughout the world. Statistics show that fishermen on Lake Victoria particularly on the Kenyan side experience many natural and technological hazards including floods and storms.Vulnerability of fishermen to natural hazards is increasingly becoming a global concern. Consequently, fishermen have devised their own local coping mechanisms to the vulnerabilities posed by natural and technological hazards. However, in Kenya, little has been documented on the coping strategies employed by fishermen in relation to the existing natural and technological hazards. The overall objective of the study, therefore, was to assess the vulnerability of fishermen to natural and technological hazards on the Kenyan side of Lake Victoria. Specifically, the study sought to: establish natural and technological hazards affecting fishermen on the Kenyan side of Lake Victoria; examine factors contributing to vulnerability of fishermen to these hazards and to evaluate the effectiveness of coping strategies employed by fishermen in relation to the existing hazards. A cross-Sectional research design was employed. The study population was 40078 which comprised of fishermen, village elders, Beach Management Units (BMU) managers, Government officers. The researcher selected a sample of 625 respondents which included a sample size of 401 fishermen, and 84 key informants and 140 participants in focus group discussions. There were 14 focus group discussions each comprising of 10 participants.Cluster and random sampling techniques were used to select fishermenwith subcounties being the basis of clustering before applying simple random techniques. Key informants were sampled purposively. Questionnaires were used to obtain data from fishermen, while interview schedules were used to obtain data from key informants. The study employed observation checklists. Content validity was established by expert judgment. Cronbach alpha coefficient was obtained to establish reliability of instruments. The data was coded and analyzed using descriptive statistics and presented using frequencies which was obtained to show distribution of responses. Spearman rho correlation analysis was conducted to establish the relationships between the study variables. Results were displayed using bar graphs, tables, pie charts and bar charts to present the data. The findings of the study revealed that fishermenon the Kenyan side of Lake Victoria were vulnerable to natural and technological hazards. The study recommended that more emphasis should be placed on community awareness/capacity building on metrological hazards in the Lake; mitigation and adaptation measures targeting disaster risk reduction in Lake Victoria should focus on addressing the safety of vessels particularly boats and perception of risk by the fishermen and any effort to address disaster risks at the lake should build on the local adaptations because on the overall they contributed to lake disaster risk reduction.
The Solar Flux Dependence of Ionospheric 150 km Radar Echoes and Implications
Authors: Patra A. K. , Pavan Chaitanya P. , St.‐Maurice J.‐P. , Otsuka Y. , Yokoyama T. , Yamamoto M.
Published: November 2017

Radar echoes from the daytime equatorial ionospheric F1 region, popularly known as “150 km echoes,” have challenged ionospheric plasma physicists for several decades. Recent theoretical simulations showed that enhanced photoelectron fluxes can amplify the amplitude of plasma waves, generating spectra similar to those of the radar echoes, implying that larger solar fluxes should produce more frequent and stronger 150 km echoes. Inspired by this proposal, we studied the occurrence and intensity dependence of the echoes on the EUV flux observed by SOHO over several years. The occurrence and intensity of the echoes were found to have an inverse relationship with this EUV flux measurement. The multiyear trend is independent of the variability often observed over successive days with nearly identical EUV fluxes. These results imply that the relationship between the echoes and EUV flux is more complex. We propose that gravity waves modulate the amplitude of 150 km echoes through changes in the variations in plasma density and photoelectron fluxes associated with the gravity wave‐induced neutral density modulations.
P and S Velocity Structure in the Groningen Gas Reservoir From Noise Interferometry
Authors: Zhou Wen , Paulssen Hanneke
Published: November 2017

Noise interferometry has proven to be a powerful tool to image seismic structure. In this study we used data from 10 geophones located in a borehole at ∼3 km depth within the Groningen gas reservoir in the Netherlands. The continuous data cross correlations show that noise predominantly comes in from above. The observed daily and weekly variations further indicate that the noise has an anthropogenic origin. The direct P wave emerges from the stacked vertical component cross correlations with frequencies up to 80 Hz and the direct S wave is retrieved from the horizontal components with frequencies up to 50 Hz. The measured intergeophone travel times were used to retrieve the P and S velocity structure along the borehole, and a good agreement was found with well log data. In addition, from the S wave polarizations, we determined azimuthal anisotropy with a fast direction of N65°W±18° and an estimated magnitude of (4±2)%. The fast polarization direction corresponds to the present direction of maximum horizontal stress measured at nearby boreholes but is also similar to the estimated paleostress direction.
USArray Imaging of Continental Crust in the Conterminous United States
Authors: Ma Xiaofei , Lowry Anthony R.
Published: November 2017

The thickness and bulk composition of continental crust provide important constraints on the evolution and dynamics of continents. Crustal mineralogy and thickness both may influence gravity anomalies, topographic elevation, and lithospheric strength, but prior to the inception of EarthScope's USArray, seismic measurements of crustal thickness and properties useful for inferring lithology are sparse. Here we improve upon a previously published methodology for joint inversion of Bouguer gravity anomalies and seismic receiver functions by using parameter space stacking of cross correlations of modeled synthetic and observed receiver functions instead of standard H‐κ amplitude stacking. The new method is applied to estimation of thickness and bulk seismic velocity ratio, vP/vS, of continental crust in the conterminous United States using USArray and other broadband network data. Crustal thickness variations are reasonably consistent with those found in other studies and show interesting relationships to the history of North American continental formation. Seismic velocity ratios derived in this study are more robust than in other analyses and hint at large‐scale variations in composition of continental crust. To interpret the results, we model the pressure‐/temperature‐dependent thermodynamics of mineral formation for various crustal chemistries, with and without volatile constituents. Our results suggest that hydration lowers bulk crustal vP/vS and density and releases heat in the shallow crust but absorbs heat in the lowermost crust (where plagioclase breaks down to pyroxene and garnet resulting in higher seismic velocity). Hence, vP/vS variations may provide a useful proxy for hydration state in the crust.
Plant Embryogenesis—The Cellular Design of a Plant
Authors: Perez‐Grau Luis
Published: November 2017

The sections in this article are

Introduction

Embryo Development inArabidopsisis Representative of Many Dicot Plants

Early Embryogenesis Integrates Two Developmental Programs

Early Embryo Development Requires Control of Cell Plate Formation and Cell Wall Position

Regional Specification Processes Define Embryo Domains with Different Developmental Roles

Integrative Development of the Embryo

Prospects

Acknowledgements
Calcium Signals and Their Regulation
Authors: Pei Zhen‐Ming , Gilroy Simon
Published: November 2017

Calcium is recognized as a ubiquitous cellular regulator and changes in cytosolic Ca2+levels are known to be involved in plant processes as diverse as response to cold shock, hormone action, and touch signaling. The specificity of subsequent cellular response appears to be encoded, at least in part, in the temporal and spatial dynamics of the Ca2+change and the spectrum of Ca2+‐responsive proteins expressed in the cell. In this chapter we review the evidence for the informational content of the Ca2+signal in plant cells and discuss our current knowledge of the channel and pump systems that shape these Ca2+changes. We will also use the Ca2+‐dependent Nod‐factor signaling system that underlies rhizobium:plant interactions to highlight our current understanding of how the Ca2+change may be transduced to the appropriate cellular response. In addition we use the example of Ca2+uptake from soil and its subsequent translocation through the plant to show how, in addition to its role in cell signaling, this ion can act as a long‐range messenger, integrating the cellular activity of the stomatal guard cell with water and nutrient uptake activities in the root. The theme that emerges from these examples is that although Ca2+is involved in regulating a remarkably diverse array of plant processes, the more we understand about the systems that generate and respond to these Ca2+changes, the more we realize just how sophisticated the molecular networks that encode and decode them turn out to be.
Fungal and Oomycete Biotrophy
Authors: de Jong Mark , van den Ackerveken Guido
Published: November 2017

Biotrophic fungal and oomycete pathogens have strikingly similar mechanisms to invade plants and retrieve nutrients. In particular, the obligate biotrophs form specialised feeding structures such as haustoria and intracellular hyphae that play an important role in host–pathogen signalling and nutrient retrieval. To establish a successful infection, pathogens need to overcome host defences, and suppression of plant defence responses is now a well‐known phenomenon in disease. The molecular mechanisms of defence suppression by fungal and oomycete pathogens likely occurs via secreted or translocated effector proteins whose primary function is to establish compatibility. Many fungal and oomycete effector proteins are transported inside the host cell. In interactions with an obligate biotroph, the host provides the necessary nutrients for pathogen growth and reproduction. Specific transporters and metabolic enzymes in both host and pathogen contribute to nutrient exchange between the two organisms and hijacking of the host source–sink balance seems to be important for infection. Studies of plant–biotrophic fungal and plant–oomycete pathogen interactions, now exploiting a wealth of pathogen genome information, are providing unique insights into molecular mechanisms determining disease susceptibility and resistance.
Asymmetric Vinylogous Mannich‐Type Addition of α,α‐Dicyanoalkenes to α‐Fluoroalkyl Sulfinyl Imines
Authors: Sanz‐Vidal Álvaro , Torres Javier , Soloshonok Vadim A. , Zhu Yi , Han Jianlin , Fustero Santos , del Pozo Carlos
Published: November 2017

The asymmetric vinylogous Mannich reaction (AVMR) of α,α‐dicyanoalkenes with α‐fluoroalkyl sulfinyl imines has been successfully accomplished. This transformation is unprecedented with fluorinated imines and, at the same time, the use of dicyanoalkenes in AVMR has been scarcely reported. Several fluorinated sulfinyl imines are compatible with the process, which gives access to a family of chiral fluorinated amines with an excellent level of stereocontrol. Interestingly, the selectivity found in our protocol is the opposite of that encountered in analogous, previously reported AVMRs. Additionally, the synthetic applicability of the addition products has been exemplified with several transformations showing the particular reactivity of the dicyanoalkene moiety of these α‐fluorinated amines.

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Interstitial microdeletion of 17q11.2 is associated with hypotonia, fatigue, intellectual disability, and a subtle facial phenotype in three unrelated patients
Authors: Osio Deborah , Rankin Julia , Koillinen Hannele , Reynolds Adele , Van Esch Hilde
Published: November 2017

Over the past decade chromosomal microarray analysis (array CGH) has allowed the discovery of many novel disease‐causing recurrent microdeletion and microduplication syndromes. Here we present three unrelated patients (2F; 1M) from three different countries, with developmental delay, intellectual disability, hypotonia, fatigue, and highly similar dysmorphic facial features. Shared facial features are a broad and wide forehead, similar shape of the eyes with long palpebral fissures, a bulbous tip of the nose and thick lips. Intellectual disabilities range from mild to severe. One female patient and the male patient were investigated in childhood for significant hypotonia thought to be suggestive of a neuromuscular disorder. The two female patients also show excessive fatigue with daytime somnolence. The patients carry overlapping, de novo microdeletions of chromosome 17q11.2, with sizes ranging from 0.97 to 1.18 Mb. The smallest region of overlap (SRO) between the three patients is 863 kb, and contains seven genes, five of which are predicted to exhibit haploinsufficiency (CDK5R1, PSMD11, RHOT1, SUZ12, ZNF207) although none has yet been associated with genetic syndromes. Of these five genes, the brain expressed CDK5R1 gene constitutes a good candidate for the developmental delay, while the RHOT1 gene, involved in mitochondrial trafficking, might underlie the hypotonia and the excessive fatigue.
Further delineation of the GDF6 related multiple synostoses syndrome
Authors: Terhal Paulien A. , Verbeek Nienke E. , Knoers Nine , Nievelstein Rutger J. A. J. , van den Ouweland Ans , Sakkers Ralph J. , Speleman Lucienne , van Haaften Gijs
Published: November 2017

A mutation in GDF6 was recently found to underlie a multiple synostoses syndrome. In this report, we describe the second family with GDF6‐related multiple synostoses syndrome (SYNS4), caused by a novel c.1287C>A/p.Ser429Arg mutation in GDF6. In addition to synostoses of carpal and/or tarsal bones, at least 6 of 10 affected patients in this family have been diagnosed with mild to moderate hearing loss. In four of them otosclerosis was said to be present, one patient had hearing loss due to severe stapes fixation at the age of 6 years, providing evidence that hearing loss in the GDF6‐related multiple synostoses syndrome can be present in childhood. Two others had surgery for stapes fixation at adult age. We hypothesize that, identical to the recently published GDF6‐related multiple synostoses family, the p.Ser429Arg mutation also leads to a gain of function. The previously reported c.1330T>A/pTyr444Asn mutation was located in a predicted Noggin and receptor I interacting domain and the gain of function was partly due to resistance of the mutant GDF6 to the BMP‐inhibitor Noggin. The results in our family show that mutations predicting to affect the type II receptor interface can lead to a similar phenotype and that otosclerosis presenting in childhood can be part of the GDF6‐related multiple synostoses syndrome.
A homozygous deleterious CDK10 mutation in a patient with agenesis of corpus callosum, retinopathy, and deafness
Authors: Guen Vincent J. , Edvardson Simon , Fraenkel Nitay D. , Fattal‐Valevski Aviva , Jalas Chaim , Anteby Irene , Shaag Avraham , Dor Talia , Gillis David , Kerem Eitan , Lees Jacqueline A. , Colas Pierre , Elpeleg Orly
Published: November 2017

The primary cilium is a key organelle in numerous physiological and developmental processes. Genetic defects in the formation of this non‐motile structure, in its maintenance and function, underlie a wide array of ciliopathies in human, including craniofacial, brain and heart malformations, and retinal and hearing defects. We used exome sequencing to study the molecular basis of disease in an 11‐year‐old female patient who suffered from growth retardation, global developmental delay with absent speech acquisition, agenesis of corpus callosum and paucity of white matter, sensorineural deafness, retinitis pigmentosa, vertebral anomalies, patent ductus arteriosus, and facial dysmorphism reminiscent of STAR syndrome, a suspected ciliopathy. A homozygous variant, c.870_871del, was identified in the CDK10 gene, predicted to cause a frameshift, p.Trp291Alafs*18, in the cyclin‐dependent kinase 10 protein. CDK10 mRNAs were detected in patient cells and do not seem to undergo non‐sense mediated decay. CDK10 is the binding partner of Cyclin M (CycM) and CDK10/CycM protein kinase regulates ciliogenesis and primary cilium elongation. Notably, CycM gene is mutated in patients with STAR syndrome. Following incubation, the patient cells appeared less elongated and more densely populated than the control cells suggesting that the CDK10 mutation affects the cytoskeleton. Upon starvation and staining with acetylated‐tubulin, γ‐tubulin, and Arl13b, the patient cells exhibited fewer and shorter cilia than control cells. These findings underscore the importance of CDK10 for the regulation of ciliogenesis. CDK10 defect is likely associated with a new form of ciliopathy phenotype; additional patients may further validate this association.
Familial choreoathetosis due to novel heterozygous mutation in PDE10A
Authors: Narayanan Dhanya L. , Deshpande Dipti , Das Bhowmik Aneek , Varma Dandu R. , Dalal Ashwin
Published: November 2017

PDE10A encodes a dual cAMP‐cGMP phosphodiesterase that is enriched in the medium spiny neurons of the corpus striatum in the brain and plays an important role in basal ganglia circuitry. Three unrelated patients with childhood onset chorea and striatal abnormalities on MRI brain with heterozygous de novo variants in PDE10A have been described previously. Two families with eight affected individuals with biallelic mutations in PDE10A have also been described previously. We report a family with multiple affected individuals with childhood onset chorea, striatal abnormalities, and a novel heterozygous mutation, c.1001T>G(p.F334C) in PDE10A which was identified by exome sequencing.
How chromosomal deletions can unmask recessive mutations? Deletions in 10q11.2 associated with CHAT or SLC18A3 mutations lead to congenital myasthenic syndrome
Authors: Schwartz Mathias , Sternberg Damien , Whalen Sandra , Afenjar Alexandra , Isapof Arnaud , Chabrol Brigitte , Portnoï Marie‐France , Heide Solveig , Keren Boris , Chantot‐Bastaraud Sandra , Siffroi Jean‐Pierre
Published: November 2017

A congenital myasthenia was suspected in two unrelated children with very similar phenotypes including several episodes of severe dyspnea. Both children had a 10q11.2 deletion revealed by Single Nucleotide Polymorphisms array or by Next Generation Sequencing analysis. The deletion was inherited from the healthy mother in the first case. These deletions unmasked a recessive mutation at the same locus in both cases, but in two different genes: CHAT and SLC18A3.
Expanding the phenotypic spectrum of TP63‐related disorders including the first set of monozygotic twins
Authors: Wenger Tara , Li Dong , Harr Margaret H. , Tan Wen‐Hann , Pellegrino Renata , Stark Zornitza , Hakonarson Hakon , Bhoj Elizabeth J.
Published: November 2017

Individuals with Tumor Protein P63 (TP63)‐related disorders are known to present with a range of phenotypic features, including ectrodactyly, ectodermal dysplasia, cleft lip/palate, Rapp‐Hodgkin, Hay–Wells, and limb‐mammary syndromes. We present six individuals from three families, including a set of monozygotic twins, with pathogenic TP63 variants who had novel clinical findings. The twins were discordant for cleft lip and palate, and the type of hand malformations, but concordant for choanal atresia, and bilateral volar nail. Both failed newborn screening for severe combined immunodeficiency (SCID) due to T‐cell lymphopenia. The second family included three family members across two generations. Two of these three family members had orofacial clefting, but the remaining child had a laryngeal web and hydrocele with no clefting or hand anomalies, highlighting the variable expressivity in TP63‐related disorders. The individual from the third family had unilateral cleft lip and palate, hydronephrosis, and bilateral volar nails. Together, these cases illustrate that: there is significant familial variability, including discordant major but concordant minor anomalies in the first ever reported set of molecularly confirmed monozygotic twins with pathogenic variants in TP63; pathogenic variants in TP63 should be considered in individuals with volar nail, which was previously only strongly associated with 4q34 deletion syndrome; and failed SCID newborn screening due to abnormal immune functioning may be part of the phenotypic spectrum of TP63‐related disorders, as it was reported in one prior individual and two of the individuals in our case series.
DOCK3‐related neurodevelopmental syndrome: Biallelic intragenic deletion of DOCK3 in a boy with developmental delay and hypotonia
Authors: Iwata‐Otsubo Aiko , Ritter Alyssa L. , Weckselbatt Brooke , Ryan Nicole R. , Burgess David , Conlin Laura K. , Izumi Kosuke
Published: November 2017

Dedicator of cytokinesis (DOCK) family are evolutionary conserved guanine nucleotide exchange factors (GEFs) for the Rho GTPases, Rac, and Cdc42. DOCK3 functions as a GEF for Rac1, and plays an important role in promoting neurite and axonal growth by stimulating actin dynamics and microtubule assembly pathways in the central nervous system. Here we report a boy with developmental delay, hypotonia, and ataxia due to biallelic DOCK3 deletion. Chromosomal single nucleotide polymorphism (SNP) microarray analysis detected a 170 kb homozygous deletion including exons 6–12 of the DOCK3 gene at 3p21.2. Symptoms of our proband resembles a phenotype of Dock3 knockout mice exhibiting sensorimotor impairments. Furthermore, our proband has clinical similarities with two siblings with compound heterozygous loss‐of‐function mutations of DOCK3 reported in [Helbig, Mroske, Moorthy, Sajan, and Velinov (); https://doi.org/10.1111/cge.12995]. Biallelic DOCK3 mutations cause a neurodevelopmental disorder characterized by unsteady gait, hypotonia, and developmental delay.
Self‐assembled micelles prepared from poly(ɛ‐caprolactone)–poly(ethylene glycol) and poly(ɛ‐caprolactone/glycolide)–poly(ethylene glycol) block copolymers for sustained drug delivery
Authors: Sun Xiangke , Liu Xue , Li Chenglong , Wang Yuandou , Liu Li , Su Feng , Li Suming
Published: November 2017

A series of poly(ɛ‐caprolactone)–poly(ethylene glycol) (PCL‐PEG) and poly(ɛ‐caprolactone/glycolide)–poly(ethylene glycol) [P(CL/GA)‐PEG] diblock copolymers were prepared by ring‐opening polymerization of ɛ‐caprolactone or a mixture of ɛ‐caprolactone and glycolide using monomethoxy PEG (mPEG) as macroinitiator and Sn(Oct)2 as catalyst. The resulting copolymers were characterized using 1H‐NMR, gel permeation chromatography, differential scanning calorimetry, and wide‐angle X‐ray diffraction. Copolymer micelles were prepared using the nanoprecipitation method. The morphology of the micelles was spherical or worm‐like as revealed by transmission electron microscopy, depending on the copolymer composition and the length of the hydrophobic block. Introduction of the glycolide component, even in small amounts (CL/GA = 10), disrupted the chain structure and led to the formation of spherical micelles. Interestingly, the micelle size decreased with the encapsulation of paclitaxel. Micelles prepared from mPEG5000‐derived copolymers exhibited better drug loading properties and slower drug release than those from mPEG2000‐derived copolymers. Drug release was faster for copolymers with shorter PCL blocks than for those with longer PCL chains. The introduction of glycolide moieties enhanced drug release, but the overall release rate did not exceed 10% in 30 days. In contrast, drug release was enhanced in acidic media. Therefore, these bioresorbable micelles and especially P(CL/GA)‐PEG micelles with excellent stability, high drug loading content, and prolonged drug release could be promising for applications as drug carriers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45732.
A comprehensive investigation of dye–chitosan blended films for green chemistry applications
Authors: Rizzi Vito , Longo Alessandra , Placido Tiziana , Fini Paola , Gubitosa Jennifer , Sibillano Teresa , Giannini Cinzia , Semeraro Paola , Franco Esther , Ferrandiz Marcela , Cosma Pinalysa
Published: November 2017

In this paper, the ability of chitosan film to remove dyestuff from wastewater was evaluated for environmental applications, using three commercial direct azo dyes. Two chitosan films were adopted: the standard one prepared following a well‐known procedure to form it, and a novel one, with a weakly acidic character. Moreover, to improve the adsorption process, the hydrophobic character of the films was investigated. The pH of the dye solutions was also changed, showing an excellent ability in dye removal at pH 12. The films were characterized by means of spectroscopic and morphologic methods to better understand the nature of interactions between dyes and chitosan chains. Swelling ratio measurements were also performed. All analyses suggest that all dyes showed a strong affinity to chitosan polymer chains, with the presence of extended hydrogen bonds and Van der Waals forces perturbing the chitosan network. Interestingly, very good results were obtained in recycling experiments related to the dyeing capacities of chitosan blended films in the presence of textiles. An ecofriendly application is thus presented in this paper. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45945.
Addition flame‐retardant effect of nonreactive phosphonate and expandable graphite in rigid polyurethane foams
Authors: Li Linjie , Chen Yajun , Qian Lijun , Xu Bo , Xi Wang
Published: November 2017

A series of flame‐retardant rigid polyurethane foams (RPUFs) containing nonreactive phosphonate (5‐ethyl‐2‐methyl‐1,3,2‐dioxaphosphorinan‐5‐yl) methyl dimethyl phosphonate P‐oxide (EMD) and expandable graphite (EG) were prepared by water blown. The flame‐retardant properties and mechanism of EMD/EG on RPUFs were systematically investigated. The EMD/EG system effectively increased the limiting oxygen index (LOI) value and decreased the values of total heat release (THR), av‐effective heat of combustion (EHC), pk‐heat release rate (HRR), total smoke release (TSR) of RPUFs. The impact values of LOI, THR, and av‐EHC resulted by EMD/EG system are nearly equal to the sum of the impact values by EMD and EG individually in RPUFs, which implies the addition flame‐retardant effect from EMD and EG. EMD alone exerted excellent gas‐phase flame‐retardant effect by releasing PO fragments with quenching effect. The firm residue produced by EMD combined well with the loose and worm‐like expanded graphite from EG further to form compact and expanded char layer, which brought excellent barrier effect and filtration effect to matrix. That's why pk‐HRR and TSR values of RPUF reduced. Depending on the simultaneous actions of EMD/EG system in gas phase and condensed phase during combustion, the flame‐retardant effects from nonreactive phosphonate and EG on RPUFs were added together. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45960.
Melt compounded nanocomposites with semi‐interpenetrated network structure based on natural rubber, polyethylene, and carrot nanofibers
Authors: Haque Md. Minhaz‐Ul , Herrera Natalia , Geng Shiyu , Oksman Kristiina
Published: November 2017

The present study deals with the processing and characterization of cellulose nanocomposites natural rubber (NR), low‐density polyethylene (LDPE) reinforced with carrot nanofibers (CNF) with the semi‐interpenetrated network (S‐IPN) structure. The nanocomposites were compounded using a co‐rotating twin‐screw extruder where a master‐batch of NR and CNF was fed to the LDPE melt, and the NR phase was crosslinked with dicumyl peroxide. The prepared S‐IPN nanocomposites exhibited a significant improvement in tensile modulus and yield strength with 5 wt % CNF content. These improvements are due to a better phase dispersion in the S‐IPN nanocomposites compared with the normal blend materials, as demonstrated by optical microscopy, electron microscopy and ultraviolet–visible spectroscopy. The S‐IPN nanocomposite also displayed an improved crystallinity and higher thermal resistance compared with NR, CNF, and the normal blend materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45961.
Reduction of dielectric constant by nanovoids formed through chemical treatment on silica crosslinked polyimide and its effect on properties
Authors: Yoo Taewon , Ghorpade Ravindra V. , Kim Kwangin , Lee Juheon , Lee Sangyoup , Baek Seungsu , Song Jungkun , Han Haksoo
Published: November 2017

In this study, 2,7‐diamino‐9‐fluorenol (DAF) has been introduced to bond silica to the main chain of the polyimide (PI) copolymer. DAF contains a hydroxyl group that could covalently bond with silica particles. 4,4′‐(Hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 4,4′‐oxydianiline (4,4′‐ODA) have been used as monomers to form a copolymer with DAF. The variation of silica content was controlled as 5%, 7.5, 10, 12.5 wt %. Variation in silica content contributes to the formation of various size (100–410 nm) of macroporous voids after hydrofluoric acid (HF) treatment. HF etching process was introduced to dissolve the silica and form voids in the structure of PI copolymer films. Compared with conventional PI films, air voids that were formed in the PI copolymer film reduced the dielectric from 4.40 to 1.86. The reduction in the dielectric constants can be explained in terms of creating silica particles that increase the presence of air voids after HF treatment. The thermal stability was stable up to 500 °C and the modulus change was confirmed with a dynamic mechanical analysis (DMA) to evaluate the effect of silica on thermal and mechanical properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45982.
Preparation and characterizations of RTV epoxy blends using amide maleic anhydride‐g‐liquid polybutadience as both reactive toughening and curing components
Authors: Wu Di , Wang Jinwei
Published: November 2017

Amide maleic anhydride‐g‐liquid polybutadience (AMALPB) was synthesized using maleic anhydride‐g‐liquid polybutadience (MALPB) with ethylenediamine (EDA), and its structure was confirmed by FTIR and 1H‐nuclear magnetic resonance spectra, respectively. It was then used as a reactive toughening agent to make blends with diglycidyl end‐capped poly(bisphenol‐A‐co‐epichlorohydrin epoxy cured at room temperature. Their thermal decomposing behaviors did not show much difference because both EDA and AMALPB possessed similar aliphatic groups. All their glass transition temperatures (Tg) increased more than 10 °C than that of the neat epoxy, and with the addition of AMALPB, the blends were greatly strengthened upon heating as show from their storage moduli. When AMALPB was added at 10 wt %, its elongation at break increases to a maximum of 8.8% which was about two times higher than that of the neat epoxy, and its tensile strength also increased. However, the excessive addition of AMALPB resulted in an apparent decline in their tensile strength at content above 20%. The simultaneous improvements in both tensile strength and strain were attributed to the existence of well‐dispersed rubber particles in the continuous matrices performing plastic deformation that resulted from the chemical bonds of interfaces among the rubber particles and matrix, and meanwhile, inducing the deflection of the cracks. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45985.
Hydrolytic stability of polylactide and poly(methyl methacrylate) blends
Authors: Rodriguez Edwin , Shahbikian Shant , Marcos Bernard , Huneault Michel A.
Published: November 2017

The hydrolytic stability of polylactide/poly(methyl methacrylate) (PLA/PMMA) blends prepared using a twin‐screw extrusion process was investigated. The effects of hydrolysis were monitored in neutral and alkaline media at 80 °C by tracking the changes in molecular weight distribution, weight loss, water uptake, and crystallization behavior. The crystallinity of PLA in blends prior to hydrolysis was shown to be largely hindered by the presence of PMMA. However, PLA recrystallized rapidly during hydrolysis. The PMMA in the blends was shown to provide increased hydrolytic and structural stability to the blends. In the neutral medium, the presence of PMMA delayed and reduced the weight loss but did not significantly affect PLA degradation kinetics. On the other hand, in the alkaline medium, the weight loss rate was strongly decreased in presence of PMMA and the kinetics of degradation was shown to be depend on PMMA content. The microstructure of these blends throughout the hydrolysis process was also examined by scanning electron microscopy. A porous structure, with interconnected pores in the 20–50 nm range, was developed due to the selective removal of PLA. Based on these morphological observations, erosion mechanism of PLA/PMMA blends was discussed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45991.
Gene isolation using degenerate primers targeting protein motif: A laboratory exercise
Authors: Yeo Brandon Pei Hui , Foong Lian Chee , Tam Sheh May , Lee Vivian , Hwang Siaw San
Published: November 2017

Structures and functions of protein motifs are widely included in many biology‐based course syllabi. However, little emphasis is placed to link this knowledge to applications in biotechnology to enhance the learning experience. Here, the conserved motifs of nucleotide binding site‐leucine rich repeats (NBS–LRR) proteins, successfully used for the isolation and characterization of many plant resistance gene analogues (RGAs), is featured in the development of a series of laboratory experiments using important molecular biology techniques. A set of previously isolated RGA sequences is used as the model for performing sequence alignment and visualising 3D protein structure using current bioinformatics programs (Clustal Omega and Argusdock software). A pair of established degenerate primer sequences is provided for the prediction of targeted amino acids sequences in the RGAs. Reverse transcription‐polymerase chain reaction (RT‐PCR) is used to amplify RGAs from total RNA samples extracted from the tropical wild relative of black pepper, Piper colubrinum (Piperaceae). This laboratory exercise enables students to correlate specific DNA sequences with respective amino acid codes and the interaction between conserved motifs of resistance genes with putatively targeted proteins. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):47–53, 2018.
Contributions of infant vagal regulation at 1 month to subsequent joint attention abilities
Authors: Mateus Vera , Cruz Sara , Ferreira‐Santos Fernando , Osório Ana , Sampaio Adriana , Martins Carla
Published: November 2017

Since birth, humans develop an ability to regulate their inner states and behaviors, when facing demanding situations, in order to restore calmness and engage with other persons and the surrounding environment. The present study analyzed whether 1‐month infant vagal regulation to auditory stimuli was associated with later joint attention abilities—responding to and initiating joint attention—in interaction with their mothers. Twenty‐three infants were assessed and measures of respiratory sinus arrhythmia—RSA (baseline and vagal tone change during auditory stimulation) were used as index of vagal regulation. At 12‐months, joint attention behaviors were assessed in a 10‐min toy‐play mother‐infant interaction. Correlational analyses showed that lower baseline RSA and larger increases in vagal tone during auditory stimulation were related to more instances of joint attention behaviors at 12 months, especially responding to joint attention. Results suggest that distinct profiles of autonomic functioning may contribute to joint attention skills.
Short‐term physiological plasticity: Trade‐off between drought and recovery responses in three Mediterranean Cistus species
Authors: Puglielli Giacomo , Catoni Rosangela , Spoletini Alessandra , Varone Laura , Gratani Loretta
Published: November 2017

Short‐term physiological plasticity allows plants to thrive in highly variable environments such as the Mediterranean ecosystems. In such context, plants that maximize physiological performance under favorable conditions, such as Cistus spp., are generally reported to have a great cost in terms of plasticity (i.e., a high short‐term physiological plasticity) due to the severe reduction of physiological performance when stress factors occur. However, Cistus spp. also show a noticeable resilience ability in response to stress factors. We hypothesized that in Cistus species the short‐term physiological response to stress and that to subsequent recovery can show a positive trade‐off to offset the costs of the photosynthetic decline under drought. Gas exchange, chlorophyll fluorescence, and water relations were measured in C. salvifolius, C. monspeliensis, and C. creticus subsp. eriocephalus during an imposed experimental drought and subsequent recovery. Plants were grown outdoor in common garden conditions from seeds of different provenances. The short‐term physiological response to stress and that to recovery were quantified via phenotypic plasticity index (PIstress and PIrecovery, respectively). A linear regression analysis was used to identify the hypothesized trade‐off PIstress–PIrecovery. Accordingly, we found a positive trade‐off between PIstress and PIrecovery, which was consistent across species and provenances. This result contributes in explaining the profit, more than the cost, of a higher physiological plasticity in response to short‐term stress imposition for Cistus spp because the costs of a higher PIstress are payed back by an as much higher PIrecovery. The absence of leaf shedding during short‐term drought supports this view. The trade‐off well described the relative variations of gas exchange and water relation parameters. Moreover, the results were in accordance with the ecology of this species and provide the first evidence of a consistent trade‐off between the short‐term physiological responses to drought and recovery phases in Mediterranean species.
Parasite‐associated mortality in a long‐lived mammal: Variation with host age, sex, and reproduction
Authors: Lynsdale Carly L. , Mumby Hannah S. , Hayward Adam D. , Mar Khyne U. , Lummaa Virpi
Published: November 2017

Parasites can cause severe host morbidity and threaten survival. As parasites are generally aggregated within certain host demographics, they are likely to affect a small proportion of the entire population, with specific hosts being at particular risk. However, little is known as to whether increased host mortality from parasitic causes is experienced by specific host demographics. Outside of theoretical studies, there is a paucity of literature concerning dynamics of parasite‐associated host mortality. Empirical evidence mainly focuses on short‐lived hosts or model systems, with data lacking from long‐lived wild or semi‐wild vertebrate populations. We investigated parasite‐associated mortality utilizing a multigenerational database of mortality, health, and reproductive data for over 4,000 semi‐captive timber elephants (Elephas maximus), with known causes of death for mortality events. We determined variation in mortality according to a number of host traits that are commonly associated with variation in parasitism within mammals: age, sex, and reproductive investment in females. We found that potentially parasite‐associated mortality varied significantly across elephant ages, with individuals at extremes of lifespan (young and old) at highest risk. Mortality probability was significantly higher for males across all ages. Female reproducers experienced a lower probability of potentially parasite‐associated mortality than females who did not reproduce at any investigated time frame. Our results demonstrate increased potentially parasite‐associated mortality within particular demographic groups. These groups (males, juveniles, elderly adults) have been identified in other studies as susceptible to parasitism, stressing the need for further work investigating links between infection and mortality. Furthermore, we show variation between reproductive and non‐reproductive females, with mothers being less at risk of potentially parasite mortality than nonreproducers.
Investigating the effects of age‐related spatial structuring on the transmission of a tick‐borne virus in a colonially breeding host
Authors: Wanelik Klara M. , Burthe Sarah J. , Harris Mike P. , Nunn Miles A. , Godfray H. Charles J. , Sheldon Ben C. , McLean Angela R. , Wanless Sarah
Published: November 2017

Higher pathogen and parasite transmission is considered a universal cost of colonial breeding due to the physical proximity of colony members. However, this has rarely been tested in natural colonies, which are structured entities, whose members interact with a subset of individuals and differ in their infection histories. We use a population of common guillemots,Uria aalge, infected by a tick‐borne virus,Great Island virus, to explore how age‐related spatial structuring can influence the infection costs borne by different members of a breeding colony. Previous work has shown that the per‐susceptible risk of infection (force of infection) is different for prebreeding (immature) and breeding (adult) guillemots which occupy different areas of the colony. We developed a mathematical model which showed that this difference in infection risk can only be maintained if mixing between these age groups is low. To estimate mixing between age groups, we recorded the movements of 63 individually recognizable, prebreeding guillemots in four different parts of a major colony in the North Sea during the breeding season. Prebreeding guillemots infrequently entered breeding areas (in only 26% of watches), though with marked differences in frequency of entry among individuals and more entries toward the end of the breeding season. Once entered, the proportion of time spent in breeding areas by prebreeding guillemots also varied between different parts of the colony. Our data and model predictions indicate low levels of age‐group mixing, limiting exposure of breeding guillemots to infection. However, they also suggest that prebreeding guillemots have the potential to play an important role in driving infection dynamics. This highlights the sensitivity of breeding colonies to changes in the behavior of their members—a subject of particular importance in the context of global environmental change.
Pomegranate seed clustering by machine vision
Authors: Amiryousefi Mohammad Reza , Mohebbi Mohebbat , Tehranifar Ali
Published: November 2017

Application of new procedures for reliable and fast recognition and classification of seeds in the agricultural industry is very important. Recent advances in computer image analysis made applicable the approach of automated quantitative analysis in order to group cultivars according to minor differences in seed traits that would be indiscernible in ocular inspection. In this work, in order to cluster 20 cultivars of pomegranate seed, nine image features and 21 physicochemical properties of them were extracted. The aim of this study was to evaluate if the information extracted from image of pomegranate seeds could be used instead of time‐consuming and partly expensive experiments of measuring their physicochemical properties. After data reduction with principal component analysis (PCA), different kinds of overlapping between these two types of data were controlled. The results showed that clustering base on all variables of image features contain more similar cultivars with clustering base on physicochemical properties (66.67% for cluster 1, 75% for cluster 2, and 50% for cluster 3). Therefore, by applying image analysis technique, the seeds almost were placed in different pomegranate clusters without spending time and additional costs.
Surveillance and diagnosis of zoonotic foodborne parasites
Authors: Zolfaghari Emameh Reza , Purmonen Sami , Sukura Antti , Parkkila Seppo
Published: November 2017

Foodborne parasites are a source of human parasitic infection. Zoonotic infections of humans arise from a variety of domestic and wild animals, including sheep, goats, cattle, camels, horses, pigs, boars, bears, felines, canids, amphibians, reptiles, poultry, and aquatic animals such as fishes and shrimp. Therefore, the implementation of efficient, accessible, and controllable inspection policies for livestock, fisheries, slaughterhouses, and meat processing and packaging companies is highly recommended. In addition, more attention should be paid to the education of auditors from the quality control (QC) and assurance sectors, livestock breeders, the fishery sector, and meat inspection veterinarians in developing countries with high incidence of zoonotic parasitic infections. Furthermore, both the diagnosis of zoonotic parasitic infections by inexpensive, accessible, and reliable identification methods and the organization of effective control systems with sufficient supervision of product quality are other areas to which more attention should be paid. In this review, we present some examples of successful inspection policies and recent updates on present conventional, serologic, and molecular diagnostic methods for zoonotic foodborne parasites from both human infection and animal‐derived foods.
Effect of isolation techniques on the characteristics of pigeon pea (Cajanus cajan) protein isolates
Authors: Adenekan Monilola K. , Fadimu Gbemisola J. , Odunmbaku Lukumon A. , Oke Emmanuel K.
Published: November 2017

In this study, the effect of different isolation techniques on the isolated proteins from pigeon pea was investigated. Water, methanol, ammonium sulfate, and acetone were used for the precipitation of proteins from pigeon pea. Proximate composition, and antinutritional and functional properties of the pigeon pea flour and the isolated proteins were measured. Data generated were statistically analyzed. The proximate composition of the water‐extracted protein isolate was moisture 8.30%, protein 91.83%, fat 0.25%, ash 0.05%, and crude fiber 0.05%. The methanol‐extracted protein isolate composition was moisture 7.87%, protein 91.83%, fat 0.17%, and ash 0.13%, while crude fiber and carbohydrates were not detected. The composition of the ammonium sulfate‐extracted protein isolate was moisture 7.73%, protein 91.73%, fat 0.36, ash 0.13%, and crude fiber 0.67%. The acetone‐extracted protein isolate composition was moisture 8.03%, protein 91.50%, ash 0.67%, and fat 0.30%, but crude fiber and carbohydrates were not detected. The isolate precipitated with ammonium sulfate displayed the highest foaming capacity (37.63%) and foaming stability (55.75%). Isolates precipitated with methanol and acetone had the highest water absorption capacity (160%). Pigeon pea protein isolates extracted with methanol and ammonium sulfate had the highest oil absorption capacity of 145%. Protein isolates recovered through acetone and methanol had the highest emulsifying capacity of 2.23% and emulsifying stability of 91.47%, respectively. The proximate composition of the recovered protein isolates were of high purity. This shows the efficiency of the extraction techniques. The isolates had desirable solubility index. All the isolation techniques brought significant impact on the characteristics of the isolated pigeon pea protein.