Search results for: transcranial magnetic stimulation.

Authors: Meltem Haktaniyan, Eda Cagli, Irem Erel Goktepe

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Polymers that change their properties in response to different stimuli (e.g. light, temperature, pH, ionic strength or magnetic field) are called ‘smart’ or ‘stimuli-responsive polymers’. These polymers have been widely used in biomedical applications such as sensors, gene delivery, drug delivery or tissue engineering. Temperature-responsive polymers have been studied extensively for controlled drug delivery applications. As regard of pseudo-peptides, poly (2-alky-2-oxazoline)s are considered as good candidates for delivery systems due to their stealth behavior and nontoxicity. In order to build responsive multilayer films for controlled drug release applications from surface, Layer by layer technique (LBL) is a powerful technique with an advantage of nanometer scale control over spatial architecture and morphology. Multilayers can be constructed on surface where non-covalent interactions including electrostatic interactions, hydrogen bonding, and charge-transfer or hydrophobic-hydrophobic interactions. In the present study, hydrogen bounded multilayer films of poly (2-alky-2-oxazoline) s with tannic acid were prepared in order to use as a platform to release Doxorubicin (DOX) from surface with pH and thermal triggers. For this purpose, poly (2-isopropyl-2-oxazoline) (PIPOX) and poly (2-ethyl-2-oxazoline) (PETOX) were synthesized via cationic ring opening polymerization (CROP) with hydroxyl end groups. Two polymeric multilayer systems ((PETOX)/(DOX)-(TA) complexes and (PIPOX)/(DOX)-(TA) complexes) were designed to investigate of controlled release of Doxorubicin (DOX) from surface with pH and thermal triggers. The drug release profiles from the multilayer thin films with alterations of pH and temperature will been examined with UV-Vis Spectroscopy and Fluorescence Spectroscopy.

Keywords: temperature responsive polymers, h-bonded multilayer films, drug release, polyoxazoline

Procedia PDF Downloads 289

Authors: Nacera Yassa, Abdelmalek Saidoune, Ghania Ouadfel, Hamza Houassine

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The rapid advancement in electrical technologies has underscored the increasing importance of multiphase machines across various industrial sectors. These machines offer significant advantages in terms of efficiency, compactness, and reliability compared to their single-phase counterparts. However, early detection and diagnosis of electrical faults remain critical challenges to ensure the durability and safety of these complex systems. This paper presents an advanced analytical model for multiphase machines, with a particular focus on dual stator asynchronous machines. The primary objective is to develop a robust diagnostic tool capable of effectively detecting and locating electrical faults in these machines, including short circuits, winding faults, and voltage imbalances. The proposed methodology relies on an analytical approach combining electrical machine theory, modeling of magnetic and electrical circuits, and advanced signal analysis techniques. By employing detailed analytical equations, the developed model accurately simulates the behavior of multiphase machines in the presence of electrical faults. The effectiveness of the proposed model is demonstrated through a series of case studies and numerical simulations. In particular, special attention is given to analyzing the dynamic behavior of machines under different types of faults, as well as optimizing diagnostic and recovery strategies. The obtained results pave the way for new advancements in the field of multiphase machine diagnostics, with potential applications in various sectors such as automotive, aerospace, and renewable energies. By providing precise and reliable tools for early fault detection, this research contributes to improving the reliability and durability of complex electrical systems while reducing maintenance and operation costs.

Keywords: faults, diagnosis, modelling, multiphase machine

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Authors: Gary J. Pickering, Sarah Lucas, Catherine E. Klodnicki, Nicole J. Gaudette

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Two taste pheno types that are of interest in the study of habitual diet-related risk factors and disease are 6-n-propylthiouracil (PROP) responsiveness and thermal tasting. Individuals differ considerable in how intensely they experience the bitterness of PROP, which is partially explained by three major single nucleotide polymorphisms associated with the TAS2R38 gene. Importantly, this variable responsiveness is a useful proxy for general taste responsiveness, and links to diet-related disease risk, including body mass index, in some studies. Thermal tasting - a newly discovered taste phenotype independent of PROP responsiveness - refers to the capacity of many individuals to perceive phantom tastes in response to lingual thermal stimulation, and is linked with TRPM5 channels. Thermal tasters (TTs) also experience oral sensations more intensely than thermal non-tasters (TnTs), and this was shown to associate with differences in self-reported food preferences in a previous survey from our lab. Here we report on two related studies, where we sought to determine whether PROP responsiveness and thermal tasting would associate with perceptual differences in the oral sensations elicited by sampled energy-dense foods, and whether in turn this would influence liking. We hypothesized that hyper-tasters (thermal tasters and individuals who experience PROP intensely) would (a) rate sweet and high-fat foods more intensely than hypo-tasters, and (b) would differ from hypo-tasters in liking scores. (Liking has been proposed recently as a more accurate measure of actual food consumption). In Study 1, a range of energy-dense foods and beverages, including table cream and chocolate, was assessed by 25 TTs and 19 TnTs. Ratings of oral sensation intensity and overall liking were obtained using gVAS and gDOL scales, respectively. TTs and TnTs did not differ significantly in intensity ratings for most stimuli (ANOVA). In a 2nd study, 44 female participants sampled 22 foods and beverages, assessing them for intensity of oral sensations (gVAS) and overall liking (9-point hedonic scale). TTs (n=23) rated their overall liking of creaminess and milk products lower than did TnTs (n=21), and liked milk chocolate less. PROP responsiveness was negatively correlated with liking of food and beverages belonging to the sweet or sensory food grouping. No other differences in intensity or liking scores between hyper- and hypo-tasters were found. Taken overall, our results are somewhat unexpected, lending only modest support to the hypothesis that these taste phenotypes associate with energy-dense food liking and consumption through differences in the oral sensations they elicit. Reasons for this lack of concordance with expectations and some prior literature are discussed, and suggestions for future research are advanced.

Keywords: taste phenotypes, sensory evaluation, PROP, thermal tasting, diet-related health risk

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Authors: Ghazal Mortazavi, S. M. J. Mortazavi

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Electricians, power line engineers and power station workers, welders, aluminum reduction workers, MRI operators and railway workers are occupationally exposed to different levels of electromagnetic fields. Mercury is among the most toxic metals. Dental amalgam fillings cause significant exposure to elemental mercury vapour in the general population. Today, substantial evidence indicates that mercury even at low doses may lead to toxicity. Increased release of mercury from dental amalgam fillings after exposure to MRI or microwave radiation emitted by mobile phones has been previously shown by our team. Moreover, our recent studies on the effects of stronger magnetic fields entirely confirmed our previous findings. From the other point of view, we have also shown that papers which reported no increased release of mercury after MRI, may have some methodological flaws. Over the past several years, our lab has focused on the health effects of exposure of laboratory animals and humans to different sources of electromagnetic fields such as mobile phones and their base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons, and MRI. As a strong association between exposure to electromagnetic fields and mercury level has been found in our studies, our findings lead us to this conclusion that occupational exposure to electromagnetic fields in workers with dental amalgam fillings can lead to elevated levels of mercury. Studies which reported that exposure to mercury can be a risk factor of Alzheimer’s disease (AD) due to the accumulation of amyloid beta protein (Aβ) in the brain and those reported that long-term occupational exposure to high levels of electromagnetic fields can increase the risk of Alzheimer's disease and dementia in male workers support our concept and confirm the significant role of the occupational exposure to electromagnetic fields in increasing the mercury level in workers with amalgam fillings.

Keywords: occupational exposure, electromagnetic fields, workers, mercury release, dental amalgam, restorative dentistry

Procedia PDF Downloads 395

Authors: Durjoy Lahiri, Vishal Madhukar Sawale, Ashwani Bhat, Souvik Dubey, Gautam Das, Biman Kanti Roy, Suparna Chatterjee, Goutam Gangopadhyay

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Crossed aphasia has been an area of considerable interest for cognitive researchers as it offers a fascinating insight into cerebral lateralization for language function. We conducted an observational study in the stroke unit of a tertiary care neurology teaching hospital in eastern India on subjects with crossed aphasia over a period of four years. During the study period, we detected twelve cases of crossed aphasia in strongly right-handed patients, caused by ischemic stroke. The age, gender, vernacular language and educational status of the patients were noted. Aphasia type and severity were assessed using Bengali version of Western Aphasia Battery (validated). Computed tomography, magnetic resonance imaging and angiography were used to evaluate the location and extent of the ischemic lesion in brain. Our series of 12 cases of crossed aphasia included 7 male and 5 female with mean age being 58.6 years. Eight patients were found to have Broca’s aphasia, 3 had trans-cortical motor aphasia and 1 patient suffered from global aphasia. Nine patients were having very severe aphasia and 3 suffered from mild aphasia. Mirror-image type of crossed aphasia was found in 3 patients, whereas 9 had anomalous variety. In our study crossed aphasia was found to be more frequent in males. Anomalous pattern was more common than mirror-image. Majority of the patients had motor-type aphasia and no patient was found to have pure comprehension deficit. We hypothesize that in Bengali-speaking right-handed population, lexical-semantic system of the language network remains loyal to the left hemisphere even if the phonological output system is anomalously located in the right hemisphere.

Keywords: aphasia, crossed, lateralization, language function, vascular

Procedia PDF Downloads 159

Authors: Marisa Rio, Sharanya Bola, Richard H. W. Funk, Gerald Gerlach

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Cell migration, wound healing and regeneration are some of the physiological phenomena in which electric fields (EFs) have proven to have an important function. Physiologically, cells experience electrical signals in the form of transmembrane potentials, ion fluxes through protein channels as well as electric fields at their surface. As soon as a wound is created, the disruption of the epithelial layers generates an electric field of ca. 40-200 mV/mm, directing cell migration towards the wound site, starting the healing process. In vitro electrotaxis, experiments have shown cells respond to DC EFs polarizing and migrating towards one of the poles (cathode or anode). A standard electrotaxis experiment consists of an electrotaxis chamber where cells are cultured, a DC power source and agar salt bridges that help delaying toxic products from the electrodes to attain the cell surface. The electric field strengths used in such an experiment are uniform and homogeneous. In contrast, the endogenous electric field strength around a wound tend to be multi-field and non-homogeneous. In this study, we present a custom device that enables electrotaxis experiments in non-homogeneous DC electric fields. Its main feature involves the replacement of conventional metallic electrodes, separated from the electrotaxis channel by agarose gel bridges, through electrolyte-filled microchannels. The connection to the DC source is made by Ag/AgCl electrodes, incased in agarose gel and placed at the end of each microfluidic channel. An SU-8 membrane closes the fluidic channels and simultaneously serves as the single connection from each of them to the central electrotaxis chamber. The electric field distribution and current density were numerically simulated with the steady-state electric conduction module from ANSYS 16.0. Simulation data confirms the application of nonhomogeneous EF of physiological strength. To validate the biocompatibility of the device cellular viability of the photoreceptor-derived 661W cell line was accessed. The cells have not shown any signs of apoptosis, damage or detachment during stimulation. Furthermore, immunofluorescence staining, namely by vinculin and actin labelling, allowed the assessment of adhesion efficiency and orientation of the cytoskeleton, respectively. Cellular motility in the presence and absence of applied DC EFs was verified. The movement of individual cells was tracked for the duration of the experiments, confirming the EF-induced, cathodal-directed motility of the studied cell line. The in vitro monolayer wound assay, or “scratch assay” is a standard protocol to quantitatively access cell migration in vitro. It encompasses the growth of a confluent cell monolayer followed by the mechanic creation of a scratch, representing a wound. Hence, wound dynamics was monitored over time and compared for control and applied the electric field to quantify cellular population motility.

Keywords: DC non-homogeneous electric fields, electrotaxis, microfluidic biochip, wound healing

Procedia PDF Downloads 249

Authors: Chukwudalu C. Nwazojie, Wole W. Soboyejo, John Obayemi, Ali Salifu Azeko, Sandra M. Jusu, Chinyerem M. Onyekanne

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The conventional methods for the diagnosis and treatment of breast cancer include bulk systematic mammography, ultrasound, dynamic contrast-enhanced fast 3D gradient-echo (GRE) magnetic resonance imaging (MRI), surgery, chemotherapy, and radiotherapy. However, nanoparticles and drug-loaded polymer microspheres for disease (cancer) targeting and treatment have enormous potential to enhance the approaches that are used today. The goal is to produce an implantable biomedical device for localized breast cancer drug delivery within Africa and the world. The main advantage of localized delivery is that it reduces the amount of drug that is needed to have a therapeutic effect. Polymer blends of poly (D,L-lactide-co-glycolide) (PLGA) and polycaprolactone (PCL), which are biodegradable, is used as a drug excipient. This work focuses on the development of PLGA-PCL (poly (D,L-lactide-co-glycolide) (PLGA) blended with based injectable drug microspheres and are loaded with anticancer drugs (prodigiosin (PG), and paclitaxel (PTX) control) and also the conjugated forms of the drug functionalized with LHRH (luteinizing hormone-releasing hormone) (PG-LHRH, and PTX- LHRH control), using a single-emulsion solvent evaporation technique. The encapsulation was done in the presence of PLGA-PCL (as a polymer matrix) and poly-(vinyl alcohol) (PVA) (as an emulsifier). Comparative study of the various drugs release kinetics and degradation mechanisms of the PLGA-PCL with an encapsulated drug is achieved, and the implication of this study is for the potential application of prodigiosin PLGA-PCL loaded microparticles for controlled delivery of cancer drug and treatment to prevent the regrowth or locoregional recurrence, following surgical resection of triple-negative breast tumor.

Keywords: cancer, polymers, drug kinetics, nanoparticles

Procedia PDF Downloads 76

Authors: Wasim Sajjad, Manzoor Ahmad, Sundas Qadir, Muhammad Rafiq, Fariha Hasan, Richard Tehan, Kerry L. McPhail, Aamer Ali Shah

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Aim: This study aims to investigate the possible radiation protective role of a compatible solute in the tolerance of radio-halophilic bacterium against stresses, like desiccation and exposure to ionizing radiation. Methods and Results: Nine different radio-resistant bacteria were isolated from desert soil, where strain WMA-LM19 was chosen for detailed studies on the basis of its high tolerance for ultraviolet radiation among all these isolates. 16S rRNA gene sequencing indicated that the bacterium was closely related to Stenotrophomonas sp. (KT008383). A bacterial milking strategy was applied for extraction of intracellular compatible solutes in 70% (v/v) ethanol, which were purified by high-performance liquid chromatography (HPLC). The compound was characterized as ectoine by 1H and 13C nuclear magnetic resonance (NMR), and mass spectrometry (MS). Ectoine demonstrated more efficient preventive activity (54.80%) to erythrocyte membranes and also inhibited oxidative damage to proteins and lipids in comparison to the standard ascorbic acid. Furthermore, a high level of ectoine-mediated protection of bovine serum albumin against ionizing radiation (1500-2000 Jm-2) was observed, as indicated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. Conclusion: The results indicated that ectoine can be used as a potential mitigator and radio-protective agent to overcome radiation- and salinity-mediated oxidative damage in extreme environments. Significance and Impact of the Study: This study shows that ectoine from radio-halophiles can be used as a potential source in topical creams as sunscreen. The investigation of ectoine as UV protectant also changes the prospective that radiation resistance is specific only to molecular adaptation.

Keywords: ectoine, anti-oxidant, stenotrophomonas sp., ultraviolet radiation

Procedia PDF Downloads 187

Authors: Aysheh Maslamani, Ella Daniel, Anna Dӧring, Iyas Nasser, Ariel Knafo-Noam

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Over 250 million people globally speak Arabic, one of the most widespread languages in the world, as their first language. Yet only a minuscule fraction of developmental research studies Middle East children. As values are a core component of culture, understanding how values develop is key to understanding development across cultures. Indeed, with the advent of research on value development, significantly since the introduction of the Picture-Based Value Survey for Children, interest in cross-cultural differences in children's values is increasing. As no measure exists for Arab children, PBVS-C in Arabic developed. The online application version of the PBVS-C that can be administered on a computer, tablet, or even a smartphone to measure the 10 values whose presence has been repeatedly demonstrated across the world. The application has been developed simultaneously in Hebrew and Arabic and can easily be adapted to include additional languages. In this research, the development of the multilingual PBVS-C application version adapted for five-year-olds. The translation process discussed (including important decisions such as which dialect of Arabic, a diglossic language, is most suitable), adaptations to subgroups (e.g., Muslim, Druze and Christian Arab children), and using recorded instructions and value item captions, as well as touchscreens to enhance applicability with young children. Four hundred Palestinian and Israeli 5-12 year old children reported their values using the app (50% in Arabic, 50% in Hebrew). Confirmatory Multidimensional Scaling (MDS) analyses revealed structural patterns that closely correspond to Schwartz's theoretical structure in both languages (e.g., universalism values correlated positively with benevolence and negatively with power, whereas tradition correlated negatively with hedonism and positively with conformity). Replicating past findings, power values showed lower importance than benevolence values in both cultural groups, and there were gender differences in which girls were higher in self-transcendence values and lower in self-enhancement values than boys. Cultural value importance differences were explored and revealed that Palestinian children are significantly higher in tradition and achievement values compared to Israeli children, whereas Israeli children are significantly higher in benevolence, hedonism, self-direction, and stimulation values. Age differences in value coherence across the two groups were also studied. Exploring the cultural differences opens a window to understanding the basic motivations driving populations that were hardly studied before. This study will contribute to the developmental value research since it considers the role of critical variables such as culture and religion and tests value coherence across middle childhood. Findings will be discussed, and the potential and limitations of the computerized PBVS-C concerning future values research.

Keywords: Arab-children, culture, multilingual-application, value-development

Procedia PDF Downloads 62

Authors: Emmanuel Kamal Aziz Saba, Gihan Abd El-Lateif Younis El-Tantawi, Mohammed Hamdy Zahran, Ibrahim Khalil Ibrahim, Mohammed Abd El-Salam Shehata, Hussein Al-Moghazy Sultan, Medhat

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Pelvic floor electrophysiological tests are essential for assessment of patients with obstructed defecation. The present study was conducted to determine the different patterns of pelvic floor electrophysiology that are associated with obstructed defecation. The present cross sectional study included 25 patients with obstructed defecation. A control group of 20 apparently healthy subjects were included. All patients were subjected to history taking, clinical examination, proctosigmoidoscopy, lateral proctography (evacuation proctography), dynamic pelvic magnetic resonance imaging, anal manometry and electrophysiological studies. Electrophysiological studies were including pudendal nerve motor conduction study, pudendo-anal reflex, needle electromyography of external anal sphincter and puborectalis muscles, pudendal somatosensory evoked potential and tibial somatosensory evoked potential. The control group was subjected to electrophysiological studies which included pudendal nerve motor conduction study, pudendo-anal reflex, pudendal somatosensory evoked potential and tibial somatosensory evoked potential. The most common pelvic floor electrodiagnostic pattern characteristics of obstructed defecation was pudendal neuropathy, denervation and anismus of external anal sphincter and puborectalis with complete interference pattern of external anal sphincter and puborectalis at squeezing and cough and no localized defect in external anal sphincter. In conclusion, there were characteristic pelvic floor electrodiagnostic patterns associated with obstructed defecation.

Keywords: obstructed defecation, pudendal nerve terminal motor latency, pudendoanal reflex, sphincter electromyography

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Authors: Asif Mahmood, Yousef Alzeghayer

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The size effects of a precursor Y2BaCuO5 (Y211) powder on the microstructure and critical current density (Jc) of liquid infiltration growth (LIG)-processed YBa2Cu3O7-y (Y123) bulk superconductors were investigated in terms of milling time (t). YBCO bulk samples having high Jc values have been selected for the flywheel energy storage system. Y211 powders were attrition-milled for 0-10 h in 2 h increments at a fixed rotation speed of 400 RPM. Y211 pre-forms were made by pelletizing the milled Y211 powders followed by subsequent sintering, after which an LIG process with top seeding was applied to the Y211/Ba3Cu5O8 (Y035) pre-forms. Spherical pores were observed in all LIG-processed Y123 samples, and the pore density gradually decreased as t increased from 0 h to 8 h. In addition to the reduced pore density, the Y211 particle size in the final Y123 products also decreased with increasing t. As t increased further to 10 h, unexpected Y211 coarsening and large pore evolutions were observed. The magnetic susceptibility-temperature curves showed that the onset superconducting transition temperature (Tc, onset) of all samples was the same (91.5 K), but the transition width became greater as t increased. The Jc of the Y123 bulk superconductors fabricated in this study was observed to correlate well with t of the Y211 precursor powder. The maximum Jc of 1.0×105 A cm-2 (at 77 K, 0 T) was achieved at t = 8 h, which is attributed to the reduction in pore density and Y211 particle size. The prolonged milling time of t = 10 h decreased the Jc of the LIG-processed Y123 superconductor owing to the evolution of large pores and exaggerated Y211 growth. YBCO bulk samples having high Jc (samples prepared using 8 h milled powders) have been used for the energy storage system in flywheel energy storage system.

Keywords: critical current, bulk superconductor, liquid infiltration, bioinformatics

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Authors: Ramin Ghasemi Shayan, Morteza Janebifam

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Tumors are regularly inhomogeneous. Provincial varieties in death, metabolic action, multiplication and body part are watched. There’s expanding proof that strong tumors may contain subpopulations of cells with various genotypes and phenotypes. These unmistakable populaces of malignancy cells can connect during a serious way and may contrast in affectability to medications. Most tumors show organic heterogeneity1–3 remembering heterogeneity for genomic subtypes, varieties inside the statement of development variables and genius, and hostile to angiogenic factors4–9 and varieties inside the tumoural microenvironment. These can present as contrasts between tumors in a few people. for instance, O6-methylguanine-DNA methyltransferase, a DNA fix compound, is hushed by methylation of the quality advertiser in half of glioblastoma (GBM), adding to chemosensitivity, and improved endurance. From the outset, there includes been specific enthusiasm inside the usage of dissemination weighted imaging (DWI) and dynamic complexity upgraded MRI (DCE-MRI). DWI sharpens MRI to water dispersion inside the extravascular extracellular space (EES) and is wiped out with the size and setup of the cell populace. Additionally, DCE-MRI utilizes dynamic obtaining of pictures during and after the infusion of intravenous complexity operator. Signal changes are additionally changed to outright grouping of differentiation permitting examination utilizing pharmacokinetic models. PET scan modality gives one of a kind natural particularity, permitting dynamic or static imaging of organic atoms marked with positron emanating isotopes (for example, 15O, 18F, 11C). The strategy is explained to a colossal radiation portion, which points of confinement rehashed estimations, particularly when utilized together with PC tomography (CT). At long last, it's of incredible enthusiasm to quantify territorial hemoglobin state, which could be joined with DCE-CT vascular physiology estimation to create significant experiences for understanding tumor hypoxia.

Keywords: heterogeneity, computerized tomography scan, magnetic resonance imaging, PET

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Authors: Heiko Weiß, Andreas Meister, Christoph Ament, Nils Dreifke

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Linear actuators are deployed in a wide range of applications. This paper presents the modeling and system identification of a variable excited linear direct drive (LDD). The LDD is designed based on linear hybrid stepper technology exhibiting the characteristic tooth structure of mover and stator. A three-phase topology provides the thrust force caused by alternating strengthening and weakening of the flux of the legs. To achieve best possible synchronous operation, the phases are commutated sinusoidal. Despite the fact that these LDDs provide high dynamics and drive forces, noise emission limits their operation in calm workspaces. To overcome this drawback an additional excitation of the magnetic circuit is introduced to LDD using additional enabling coils instead of permanent magnets. The new degree of freedom can be used to reduce force variations and related noise by varying the excitation flux that is usually generated by permanent magnets. Hence, an identified simulation model is necessary to analyze the effects of this modification. Especially the force variations must be modeled well in order to reduce them sufficiently. The model can be divided into three parts: the current dynamics, the mechanics and the force functions. These subsystems are described with differential equations or nonlinear analytic functions, respectively. Ordinary nonlinear differential equations are derived and transformed into state space representation. Experiments have been carried out on a test rig to identify the system parameters of the complete model. Static and dynamic simulation based optimizations are utilized for identification. The results are verified in time and frequency domain. Finally, the identified model provides a basis for later design of control strategies to reduce existing force variations.

Keywords: force variations, linear direct drive, modeling and system identification, variable excitation flux

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Authors: Md. M. Hossain, Regan Roat, Jenica Christopherson, Colette Free, Zhiguang Guo

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Long noncoding RNA (lncRNA) mediated post-transcriptional gene regulation, and their epigenetic landscapes have been shown to be involved in many human diseases. However, their regulation in diabetes through governing islet’s β-cell function and survival needs to be elucidated. Due to the technical and ethical constraints, it is difficult to study their role in β-cell function and survival in human under in vivo condition. In this study, humanized mice have been developed through transplanting human pancreatic islet under the kidney capsule of NOD.SCID mice and induced β-cell death leading to diabetes condition to study lncRNA mediated regulation. For this, human islets from 3 donors (3000 IEQ, purity > 80%) were transplanted under the kidney capsule of STZ induced diabetic NOD.scid mice. After at least 2 weeks of normoglycecemia, lymphocytes from diabetic NOD mice were adoptively transferred and islet grafts were collected once blood glucose reached > 200 mg/dl. RNA from human donor islets, islet grafts from humanized mice with either adoptive lymphocyte transfer (ALT) or PBS control (CTL) were ribodepleted; barcoded fragment libraries were constructed and sequenced on the Ion Proton sequencer. lncRNA expression in isolated human islets, islet grafts from humanized mice with and without induced β-cell death and their regulation in human islets function in vitro under glucose challenge, cytokine mediated inflammation and induced apoptotic condition were investigated. Out of 3155 detected lncRNAs, 299 that highly expressed in islets were found to be significantly downregulated and 224 upregulated in ALT compared to CTL. Most of these are found to be collocated within 5 kb upstream and 1 kb downstream of 788 up- and 624 down-regulated mRNAs. Genomic Regions Enrichment of Annotations Analysis revealed deregulated and collocated genes are related to pancreas endocrine development; insulin synthesis, processing, and secretion; pancreatitis and diabetes. Many of them, that found to be located within enhancer domains for islet specific gene activity, are associated to the deregulation of known islet/βcell specific transcription factors and genes that are important for β-cell differentiation, identity, and function. RNA sequencing analysis revealed aberrant lncRNA expression which is associated to the deregulated mRNAs in β-cell function as well as in molecular pathways related to diabetes. A distinct set of candidate lncRNA isoforms were identified as highly enriched and specific to human islets, which are deregulated in human islets from donors with different BMIs and with type 2 diabetes. These RNAs show an interesting regulation in cultured human islets under glucose stimulation and with induced β-cell death by cytokines. Aberrant expression of these lncRNAs was detected in the exosomes from the media of islets cultured with cytokines. Results of this study suggest that the islet specific lncRNAs are deregulated in human islet with β-cell death, hence important in diabetes. These lncRNAs might be important for human β-cell function and survival thus could be used as biomarkers and novel therapeutic targets for diabetes.

Keywords: β-cell, humanized mouse, pancreatic islet, LncRNAs

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Authors: Rajeev Kumar, Angad Singh Kushwaha, Amritanshu Pandey, S. K. Srivastava

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Photonic crystals (PCs) have attracted much attention due to its electromagnetic properties and potential applications. In PCs, there is certain range of wavelength where electromagnetic waves are not allowed to pass are called photonic band gap (PBG). A localized defect mode will appear within PBG, due to change in the interference behavior of light, when we create a defect in the periodic structure. We can also create different types of defect structures by inserting or removing a layer from the periodic layered structure in two and three-dimensional PCs. We can design microcavity, waveguide, and perfect mirror by creating a point defect, line defect, and palanar defect in two and three- dimensional PC structure. One-dimensional and two-dimensional PCs with defects were reported theoretically and experimentally by Smith et al.. in conventional photonic band gap structure. In the present paper, we have presented the defect mode tunability in tilted non-graded photonic crystal (NGPC) and linearly graded photonic crystal (LGPC) using lead sulphide (PbS) and titanium dioxide (TiO2) in the infrared region. A birefringent defect layer is created in NGPC and LGPC using potassium titany phosphate (KTP). With the help of transfer matrix method, the transmission properties of proposed structure is investigated for transverse electric (TE) and transverse magnetic (TM) polarization. NGPC and LGPC without defect layer is also investigated. We have found that a photonic band gap (PBG) arises in the infrared region. An additional defect layer of KTP is created in NGPC and LGPC structure. We have seen that an additional transmission mode appers in PBG region. It is due to the addition of defect layer. We have also seen the effect, linear gradation in thickness, angle of incidence, tilt angle, and thickness of defect layer, on PBG and additional transmission mode. We have observed that the additional transmission mode and PBG can be tuned by changing the above parameters. The proposed structure may be used as channeled filter, optical switches, monochromator, and broadband optical reflector.

Keywords: defect modes, graded photonic crystal, photonic crystal, tilt angle

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Authors: Niharika Keot, Manabendra Sarma

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A thorough investigation of Ln3+ complexes with more than one inner-sphere water molecule is crucial for designing high relaxivity contrast agents (CAs) used in magnetic resonance imaging (MRI). This study accomplished a comparative stability analysis of two hexadentate (H3cbda and H3dpaa) and two heptadentate (H4peada and H3tpaa) ligands with Ln3+ ions. The higher stability of the hexadentate H3cbda and heptadentate H4peada ligands has been confirmed by the binding affinity and Gibbs free energy analysis in aqueous solution. In addition, energy decomposition analysis (EDA) reveals the higher binding affinity of the peada4− ligand than the cbda3− ligand towards Ln3+ ions due to the higher charge density of the peada4− ligand. Moreover, a mechanistic overview of water exchange kinetics has been carried out based on the strength of the metal–water bond. The strength of the metal–water bond follows the trend Gd–O47 (w) > Gd–O39 (w) > Gd–O36 (w) in the case of the tris-aquated [Gd(cbda)(H2O)3] and Gd–O43 (w) > Gd–O40 (w) for the bis-aquated [Gd(peada)(H2O)2]− complex, which was confirmed by bond length, electron density (ρ), and electron localization function (ELF) at the corresponding bond critical points. Our analysis also predicts that the activation energy barrier decreases with the decrease in bond strength; hence kex increases. The 17O and 1H hyperfine coupling constant values of all the coordinated water molecules were different, calculated by using the second-order Douglas–Kroll–Hess (DKH2) approach. Furthermore, the ionic nature of the bonding in the metal–ligand (M–L) bond was confirmed by the Quantum Theory of Atoms-In-Molecules (QTAIM) and ELF along with energy decomposition analysis (EDA). We hope that the results can be used as a basis for the design of highly efficient Gd(III)-based high relaxivity MRI contrast agents for medical applications.

Keywords: MRI contrast agents, lanthanide chemistry, thermodynamic stability, water exchange kinetics

Procedia PDF Downloads 53

Authors: Cameron Wilson, Megan Hanrahan, Katie Brittain, Riona McArdle, Alison Keogh, Lynn Rochester

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Background: The loss of mobility and functional dependence is a significant marker in the progression of neurodegenerative diseases such as Parkinson’s Disease (PD). Pharmacological, surgical, and therapeutic treatments are available that can help in the management and amelioration of PD symptoms; however, these only prolong more severe symptoms. Accordingly, ensuring people with PD can maintain independence and a healthy wellbeing are essential in establishing an effective treatment option for those afflicted. Existing literature reviews have examined experiences in engaging with PD treatment options and the impact of PD on independence and wellbeing. Although, the literature fails to explore the influence of treatment options on independence and wellbeing and therefore misses what people value in their treatment. This review is the first that synthesises the impact of mobility-related treatments on independence and wellbeing in people with PD and their carers, offering recommendations to clinical practice and provides a conceptual framework (in development) for future research and practice. Objectives: To explore the impact of mobility-related treatment (both pharmacological and non-pharmacological) on the independence and wellbeing of people with PD and their carers. To propose a conceptual framework to patients, carers and clinicians which captures the qualities people with PD value as part of their treatment. Methods: We performed a critical interpretive synthesis of qualitative evidence, searching six databases for reports that explored the impact of mobility-related treatments (both drug and non-pharmacological) on independence and wellbeing in Parkinson’s Disease. The types of treatments included medication (Levodopa and Amantadine), dance classes, Deep-Brain Stimulation, aquatic therapies, physical rehabilitation, balance training and foetal transplantation. Data was extracted, and quality was assessed using an adapted version of the NICE Quality Appraisal Tool Appendix H before being synthesised according to the critical interpretive synthesis framework and meta-ethnography process. Results: From 2301 records, 28 were eligible. Experiences and impact of treatment pathway on independence and wellbeing was similar across all types of treatments and are described by five inter-related themes: (i) desire to maintain independence, (ii) treatment as a social experience during and after, (iii) medication to strengthen emotional health, (iv) recognising physical capacity and (v) emphasising the personal journey of Parkinson’s treatments. Conclusion: There is a complex and inter-related experience and effect of PD treatments common across all types of treatment. The proposed conceptual framework (in development) provides patients, carers, and clinicians recommendations to personalise the delivery of PD treatment, thereby potentially improving adherence and effectiveness. This work is vital to disseminate as PD treatment transitions from subjective and clinically captured assessments to a more personalised process supplemented using wearable technology.

Keywords: parkinson's disease, medication, treatment, dance, review, healthcare, delivery, levodopa, social, emotional, psychological, personalised healthcare

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Authors: Fernanda Gonçalves, Karla Alcântara, Vanessa Moura, Patrícia Nolasco, Jorge Kalil, Maristela Hernandez

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Introduction: Atherosclerosis is a chronic disease where two striking features are observed: retention of lipids and inflammation. Understanding the interaction between immune cells and lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death worldwide. Macrophages are critical to the development of atherosclerotic plaques and in the perpetuation of inflammation in these lesions. These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although the presence of M2 macrophages (macrophages activated by the alternative pathway, eg. The IL-4) has been identified, the function of these cells in atherosclerosis is not yet defined. M2 macrophages have a high endocytic capacity, they promote remodeling of tissues and to have anti-inflammatory activity. However, in atherosclerosis, especially unstable plaques, severe inflammatory reaction, accumulation of cellular debris and intense degradation of the tissue is observed. Thus, it is possible that the M2 macrophages have altered function (phenotype) in atherosclerosis. Objective: Our aim is to evaluate if the presence of oxidized LDL alters the phenotype and function of M2 macrophages in vitro. Methods: For this, we will evaluate whether the addition of lipoprotein in M2 macrophages differentiated in vitro with IL -4 induces 1) a reduction in the secretion of anti-inflammatory cytokines (CBA and ELISA), 2) secretion of inflammatory cytokines (CBA and ELISA), 3) expression of cell activation markers (Flow cytometry), 4) alteration in gene expression of molecules adhesion and extracellular matrix (Real-Time PCR) and 5) Matrix degradation (confocal microscopy). Results: In oxLDL stimulated M2 macrophages cultures we did not find any differences in the expression of the cell surface markers tested, including: HLA-DR, CD80, CD86, CD206, CD163 and CD36. Also, cultures stimulated with oxLDL had similar phagocytic capacity when compared to unstimulated cells. However, in the supernatant of these cultures an increase in the secretion of the pro-inflammatory cytokine IL-8 was detected. No significant changes where observed in IL-6, IL-10, IL-12 and IL-1b levels. The culture supernatant also induced massive extracellular matrix (produced by mouse embryo fibroblast) filaments degradation. When evaluating the expression of 84 extracellular matrix and adhesion molecules genes, we observed that the stimulation of oxLDL in M2 macrophages decreased 47% of the genes and increased the expression of only 3% of the genes. In particular we noted that oxLDL inhibit the expression of 60% of the genes constituents of extracellular matrix and collagen expressed by these cells, including fibronectin1 and collagen VI. We also observed a decrease in the expression of matrix protease inhibitors, such as TIMP 2. On the opposite, the matricellular protein thrombospondin had a 12 fold increase in gene expression. In the presence of native LDL 90% of the genes had no altered expression. Conclusion: M2 macrophages stimulated with oxLDL secrete the pro-inflammatory cytokine IL-8, have an altered extracellular matrix constituents gene expression, and promote the degradation of extracellular matrix. M2 macrophages may contribute to the perpetuation of inflammation in atherosclerosis and to plaque rupture.

Keywords: atherosclerosis, LDL, macrophages, m2

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Authors: Fathi Kallel, Abdulelah Alabd Uljabbar, Abdulrahman Aldukhail, Abdulaziz Alomran

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The brain is an important organ in our body since it is responsible about the majority actions such as vision, memory, etc. However, different diseases such as Alzheimer and tumors could affect the brain and conduct to a partial or full disorder. Regular diagnosis are necessary as a preventive measure and could help doctors to early detect a possible trouble and therefore taking the appropriate treatment, especially in the case of brain tumors. Different imaging modalities are proposed for diagnosis of brain tumor. The powerful and most used modality is the Magnetic Resonance Imaging (MRI). MRI images are analyzed by doctor in order to locate eventual tumor in the brain and describe the appropriate and needed treatment. Diverse image processing methods are also proposed for helping doctors in identifying and analyzing the tumor. In fact, a large Computer Aided Diagnostic (CAD) tools including developed image processing algorithms are proposed and exploited by doctors as a second opinion to analyze and identify the brain tumors. In this paper, we proposed a new advanced CAD for brain tumor identification, classification and feature extraction. Our proposed CAD includes three main parts. Firstly, we load the brain MRI. Secondly, a robust technique for brain tumor extraction is proposed. This technique is based on both Discrete Wavelet Transform (DWT) and Principal Component Analysis (PCA). DWT is characterized by its multiresolution analytic property, that’s why it was applied on MRI images with different decomposition levels for feature extraction. Nevertheless, this technique suffers from a main drawback since it necessitates a huge storage and is computationally expensive. To decrease the dimensions of the feature vector and the computing time, PCA technique is considered. In the last stage, according to different extracted features, the brain tumor is classified into either benign or malignant tumor using Support Vector Machine (SVM) algorithm. A CAD tool for brain tumor detection and classification, including all above-mentioned stages, is designed and developed using MATLAB guide user interface.

Keywords: MRI, brain tumor, CAD, feature extraction, DWT, PCA, classification, SVM

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Authors: Janet Wing-Chong Wai, Alex Chiu-Wing Lee, Hailey Hoi-Ching Tsang, Jeffrey Chiu, Kwok-Wing Tang

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Background: Mammography has limited sensitivity and specificity though it is the primary imaging technique for detection of early breast cancer. Ultrasound imaging and contrast-enhanced MRI are useful adjunct tools to mammography. The advantage of breast MRI is high sensitivity for invasive breast cancer. Therefore, indications for and use of breast magnetic resonance imaging have increased over the past decade. Objectives: 1. Cases demonstration on different indications for breast MR imaging. 2. To review of the common artifacts and pitfalls in breast MR imaging. Materials and Methods: This is a retrospective study including all patients underwent dynamic contrast-enhanced breast MRI examination in our centre, performed from Jan 2011 to Dec 2017. The clinical data and radiological images were retrieved from the EPR (electronic patient record), RIS (Radiology Information System) and PACS (Picture Archiving and Communication System). Results and Discussion: Cases including (1) Screening of the contralateral breast in patient with a new breast malignancy (2) Breast augmentation with free injection of unknown foreign materials (3) Finding of axillary adenopathy with an unknown site of primary malignancy (4) Neo-adjuvant chemotherapy: before, during, and after chemotherapy to evaluate treatment response and extent of residual disease prior to operation. Relevant images will be included and illustrated in the presentation. As with other types of MR imaging, there are different artifacts and pitfalls that can potentially limit interpretation of the images. Because of the coils and software specific to breast MR imaging, there are some other technical considerations that are unique to MR imaging of breast regions. Case demonstration images will be available in presentation. Conclusion: Breast MR imaging is a highly sensitive and reasonably specific method for the detection of breast cancer. Adherent to appropriate clinical indications and technical optimization are crucial for achieving satisfactory images for interpretation.

Keywords: MRI, breast, clinical, cancer

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Authors: Xiaoqing Liu, Kurt Friese, Karsten Rinke

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Lacustrine sediment archives rich paleoenvironmental information in lake and surrounding environment. Additionally, modern sediment is used as an effective medium for the monitoring of lake. Organic carbon in sediment is a heterogeneous mixture with varying turnover times and qualities which result from the different biogeochemical processes in the deposition of organic material. Therefore, the isolation of different carbon pools is important for the research of lacustrine condition in the lake. However, the numeric available fractionation procedures can hardly yield homogeneous carbon pools on terms of stability and age. In this work, a multi-step fractionation protocol that treated sediment with hot water, HCl, H2O2 and Na2S2O8 in sequence was adopted, the treated sediment from each step were analyzed for the isotopic and structural compositions with Isotope Ratio Mass Spectrometer coupled with element analyzer (IRMS-EA) and Solid-state 13C Nuclear Magnetic Resonance (NMR), respectively. The sequential extractions with hot-water, HCl, and H2O2 yielded a more homogeneous and C3 plant-originating OC fraction, which was characterized with an atomic C/N ratio shift from 12.0 to 20.8, and 13C and 15N isotopic signatures were 0.9‰ and 1.9‰ more depleted than the original bulk sediment, respectively. Additionally, the H2O2- resistant residue was dominated with stable components, such as the lignins, waxes, cutans, tannins, steroids and aliphatic proteins and complex carbohydrates. 6M HCl in the acid hydrolysis step was much more effective than 1M HCl to isolate a sedimentary OC fraction with higher degree of homogeneity. Owing to the extremely high removal rate of organic matter, the step of a Na2S2O8 oxidation is only suggested if the isolation of the most refractory OC pool is mandatory. We conclude that this multi-step chemical fractionation procedure is effective to isolate more homogeneous OC pools in terms of stability and functional structure, and it can be used as a promising method for OC pools fractionation of sediment or soil in future lake research.

Keywords: 13C-CPMAS-NMR, 13C signature, lake sediment, OC fractionation

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Authors: Eric Jacob Bacon, Chaoyang Jin, Dianning He, Shuaishuai Hu, Lanbo Wang, Han Li, Shouliang Qi

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Objective: Refractory epilepsy is a complicated type of epilepsy that can be difficult to diagnose. Recent technological advancements have made resting-state functional magnetic resonance (rsfMRI) a vital technique for studying brain activity. However, there is still much to learn about rsfMRI. Investigating rsfMRI connectivity may aid in the detection of abnormal activities. In this paper, we propose studying the functional connectivity of rsfMRI candidates to diagnose epilepsy. Methods: 45 rsfMRI candidates, comprising 26 with refractory epilepsy and 19 healthy controls, were enrolled in this study. A data-driven approach known as independent component analysis (ICA) was used to achieve our goal. First, rsfMRI data from both patients and healthy controls were analyzed using group ICA. The components that were obtained were then spatially sorted to find and select meaningful ones. A two-sample t-test was also used to identify abnormal networks in patients and healthy controls. Finally, based on the fractional amplitude of low-frequency fluctuations (fALFF), a chi-square statistic test was used to distinguish the network properties of the patient and healthy control groups. Results: The two-sample t-test analysis yielded abnormal in the default mode network, including the left superior temporal lobe and the left supramarginal. The right precuneus was found to be abnormal in the dorsal attention network. In addition, the frontal cortex showed an abnormal cluster in the medial temporal gyrus. In contrast, the temporal cortex showed an abnormal cluster in the right middle temporal gyrus and the right fronto-operculum gyrus. Finally, the chi-square statistic test was significant, producing a p-value of 0.001 for the analysis. Conclusion: This study offers evidence that investigating rsfMRI connectivity provides an excellent diagnosis option for refractory epilepsy.

Keywords: ICA, RSN, refractory epilepsy, rsfMRI

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Authors: Joanna Skopinska-Wisniewska, Anna Bajek, Marta Ziegler-Borowska, Alina Sionkowska

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Hydrogels are a class of materials widely used in medicine for many years. Proteins, such as collagen, due to the presence of a large number of functional groups are easily wettable by polar solvents and can create hydrogels. The supramolecular network capable to swelling is created by cross-linking of the biopolymers using various reagents. Many cross-linking agents has been tested for last years, however, researchers still are looking for a new, more secure reactants. Squaric acid, 3,4-dihydroxy 3-cyclobutene 1,2- dione, is a very strong acid, which possess flat and rigid structure. Due to the presence of two carboxyl groups the squaric acid willingly reacts with amino groups of collagen. The main purpose of this study was to investigate the influence of addition of squaric acid on the chemical, physical and biological properties of collagen materials. The collagen type I was extracted from rat tail tendons and 1% solution in 0.1M acetic acid was prepared. The samples were cross-linked by the addition of 5%, 10% and 20% of squaric acid. The mixtures of all reagents were incubated 30 min on magnetic stirrer and then dialyzed against deionized water. The FTIR spectra show that the collagen structure is not changed by cross-linking by squaric acid. Although the mechanical properties of the collagen material deteriorate, the temperature of thermal denaturation of collagen increases after cross-linking, what indicates that the protein network was created. The lyophilized collagen gels exhibit porous structure and the pore size decreases with the higher addition of squaric acid. Also the swelling ability is lower after the cross-linking. The in vitro study demonstrates that the materials are attractive for 3T3 cells. The addition of squaric acid causes formation of cross-ling bonds in the collagen materials and the transparent, stiff hydrogels are obtained. The changes of physicochemical properties of the material are typical for cross-linking process, except mechanical properties – it requires further experiments. However, the results let us to conclude that squaric acid is a suitable cross-linker for protein materials for medicine and tissue engineering.

Keywords: collagen, squaric acid, cross-linking, hydrogel

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Authors: Da-Wei Wang, Liang Yang, Xuan-Long Peng, Mei-Chuan Kuo, Jen-Taut Yeh

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The tensile retention and waterproof properties of thermoplastic starch (TPS) resins were significantly enhanced by modifying with proper amounts of citric acid (CA) and by melt-blending with poly(lactic acid) (PLA), although no distinguished chemical reaction occurred between CA and starch molecules. As evidenced by Fourier transform infrared spectroscopy and Solid-state 13C Nuclear Magnetic Resonance analyses, disruption of intra and interhydrogen-bondings within starch molecules did occur during the modification processes of CA modified TPS (i.e. TPS100CAx) specimens. The tensile strength (σf) retention values of TPS specimens reduced rapidly from 27.8 to 20.5 and 0.4 MPa, respectively, as the conditioning time at 20°C/50% relative humidity (RH) increased from 0 to 7 and 70 days, respectively. While the elongation at break (εf) retention values of TPS specimens increased rapidly from 5.9 to 6.5 and 34.8%, respectively, as the conditioning time increased from 0 to 7 and 70 days. After conditioning at 20°C/50% RH for 70 days, the σf and εf retention values of the best prepared (TPS100CA0.1)30PLA70 specimen are equivalent to 85% and 167% of its initial σf and εf values, respectively, and are more than 105 times higher but 48% lower than those of TPS specimens conditioned at 20°C/50% RH for the same amount of time. Demarcated diffraction peaks, new melting endotherms of recrystallized starch crystals and distinguished ductile characteristics with drawn debris were found for many conditioned TPS specimens, however, only slight retrogradation effect and much less drawn debris was found for most conditioned TPS100CAx and/or (TPS100CA0.1)xPLAy specimens. The significantly improved water proof, tensile retention properties and relatively unchanged in retrogradation effect found for most conditioned TPS100CAx and/or (TPS100CA0.1)xPLAy specimens are apparently due to the efficient blocking of the moisture-absorbing hydroxyl groups (free or hydrogen bonded) by hydrogen-bonding CA with starch molecules during their modification processes.

Keywords: thermoplastic starch, hydrogen-bonding, water proof, strength retention

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Authors: Angelica Alvarez-Lee, Sergio Martinez-Diaz, Jose Luis Garcia-Corona, Humberto Lanz-Mendoza

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World aquaculture is always looking for improvements to achieve productions with high yields avoiding the infection by pathogenic agents. The best way to achieve this is to know the biological model to create alternative treatments that could be applied in the hatcheries, which results in greater economic gains and improvements in human public health. In the last decade, immunomodulation in shrimp culture with probiotics, organic acids and different carbon sources has gained great interest, mainly in larval and juvenile stages. Immune priming is associated with a strong protective effect against a later pathogen challenge. This work provides another perspective about immunostimulation from spawning until hatching. The stimulation happens during development embryos and generates resistance to infection by pathogenic bacteria. Massive spawnings of white shrimp L. vannamei were obtained and placed in experimental units with 700 mL of sterile seawater at 30 °C, salinity of 28 ppm and continuous aeration at a density of 8 embryos.mL⁻¹. The immunostimulating effect of three death strains of non-pathogenic bacterial (Escherichia coli, Staphylococcus aureus and Bacillus subtilis) and a pathogenic strain for white shrimp (Vibrio parahaemolyticus) was evaluated. The strains killed by heat were adjusted to O.D. 0.5, at A 600 nm, and directly added to the seawater of each unit at a ratio of 1/100 (v/v). A control group of embryos without inoculum of dead bacteria was kept under the same physicochemical conditions as the rest of the treatments throughout the experiment and used as reference. The duration of the stimulus was 12 hours, then, the larvae that hatched were collected, counted and transferred to a new experimental unit (same physicochemical conditions but at a salinity of 28 ppm) to carry out a challenge of infection against the pathogen V. parahaemolyticus, adding directly to seawater an amount 1/100 (v/v) of the live strain adjusted to an OD 0.5; at A 600 nm. Subsequently, 24 hrs after infection, nauplii survival was evaluated. The results of this work shows that, after 24 hrs, the hatching rates of immunostimulated shrimp embryos with the dead strains of B. subtillis and V. parahaemolyticus are significantly higher compared to the rest of the treatments and the control. Furthermore, survival of L. vanammei after a challenge of infection of 24 hrs against the live strain of V. parahaemolyticus is greater (P < 0.05) in the larvae immunostimulated during the embryonic development with the dead strains B. subtillis and V. parahaemolyticus, followed by those that were treated with E. coli. In summary superficial antigens can stimulate the development cells to promote hatching and can have normal development in agreeing with the optical observations, plus exist a differential response effect between each treatment post-infection. This research provides evidence of the immunostimulant effect of death pathogenic and non-pathogenic bacterial strains in the rate of hatching and oversight of shrimp L. vannamei during embryonic and larval development. This research continues evaluating the effect of these death strains on the expression of genes related to the defense priming in larvae of L. vannamei that come from massive spawning in hatcheries before and after the infection challenge against V. parahaemolyticus.

Keywords: immunostimulation, L. vannamei, hatching, survival

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Authors: Ralene Sim, Stefan Mueller, N. Gopalakrishna Iyer, Ngian Chye Tan, Khee Chee Soo, R. Shetty Mahalakshmi, Hiang Khoon Tan

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Background: Regional failure in nasopharyngeal carcinoma (NPC) is managed by salvage treatment in the form of neck dissection. Radical neck dissection (RND) is preferred over modified radical neck dissection (MRND) since it is traditionally believed to offer better long-term disease control. However, with the advent of more advanced imaging modalities like high-resolution Magnetic Resonance Imaging, Computed Tomography, and Positron Emission Tomography-CT scans, earlier detection is achieved. Additionally, concurrent chemotherapy also contributes to reduced tumour burden. Hence, there may be a lesser need for an RND and a greater role for MRND. With this retrospective study, the primary aim is to ascertain whether MRND, as opposed to RND, has similar outcomes and hence, whether there would be more grounds to offer a less aggressive procedure to achieve lower patient morbidity. Methods: This is a retrospective study of 66 NPC patients treated at Singapore General Hospital between 1994 to 2016 for histologically proven regional recurrence, of which 41 patients underwent RND and 25 who underwent MRND, based on surgeon preference. The type of ND performed, primary treatment mode, adjuvant treatment, and pattern of recurrence were reviewed. Overall survival (OS) was calculated using Kaplan-Meier estimate and compared. Results: Overall, the disease parameters such as nodal involvement and extranodal extension were comparable between the two groups. Comparing MRND and RND, the median (IQR) OS is 1.76 (0.58 to 3.49) and 2.41 (0.78 to 4.11) respectively. However, the p-value found is 0.5301 and hence not statistically significant. Conclusion: RND is more aggressive and has been associated with greater morbidity. Hence, with similar outcomes, MRND could be an alternative salvage procedure for regional failure in selected NPC patients, allowing similar salvage rates with lesser mortality and morbidity.

Keywords: nasopharyngeal carcinoma, neck dissection, modified neck dissection, radical neck dissection

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Authors: P. Defossez, J. M. Bonnefond, D. Garrigou, P. Trichet, F. Danjon

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Windstorm damage to European forests has ecological, social and economic consequences of major importance. Most trees during storms are uprooted. While a large amount of work has been done over the last decade on understanding the aerial tree response to turbulent wind flow, much less is known about the root-soil interface, and the impact of soil moisture and root-soil system fatiguing on tree uprooting. Anchorage strength is expected to be reduced by water-logging and heavy rain during storms due to soil strength decrease with soil water content. Our paper is focused on the maritime pine cultivated on sandy soil, as a representative species of the Forêt des Landes, the largest cultivated forest in Europe. This study aims at providing knowledge on the effects of soil saturation on root anchorage. Pulling experiments on trees were performed to characterize the resistance to wind by measuring the critical bending moment (Mc). Pulling tests were performed on 12 maritime pines of 13-years old for two unsaturated soil conditions that represent the soil conditions expected in winter when wind storms occur in France (w=11.46 to 23.34 % gg⁻¹). A magnetic field digitizing technique was used to characterize the three-dimensional architecture of root systems. The soil mechanical properties as function of soil water content were characterized by laboratory mechanical measurements as function of soil water content and soil porosity on remolded samples using direct shear tests at low confining pressure ( < 15 kPa). Remarkably Mc did not depend on w but mainly on the root system morphology. We suggested that the importance of soil water conditions on tree anchorage depends on the tree size. This study gives a new insight on young tree anchorage: roots may sustain by themselves anchorage, whereas adhesion between roots and surrounding soil may be negligible in sandy soil.

Keywords: roots, sandy soil, shear strength, tree anchorage, unsaturated soil

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Authors: Akbar Esmaeili, Mahnoosh Aliahmadi

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This study synthesized a modified imaging of gallium@deferoxamine/folic acid/chitosan/polyaniline/polyvinyl alcohol (Ga@DFA/FA/CS/PANI/PVA). It contains Morus nigra extract by selenium nanoparticles prepared from Lactobacillus acidophilus. Using the impregnation method, Se nanoparticles were then deposited on (Ga@DFA/FA/ CS/PANI/PVA). The modified contrast agents were mixed with M. nigra extract, and investigated their antibacterial activities by applying to L929 cell lines. The influence of variable factors, including 1. surfactant, 2. solvent, 3. aqueous phase, 4. pH, 5. buffer, 6. minimum Inhibitory concentration (MIC), 7. minimum bactericidal concentration (MBC), 8. cytotoxicity on cancer cells., 9. antibiotic, 10. antibiogram, 11. release and loading, 12. the emotional effect, 13. the concentration of nanoparticles, 14. olive oil, and 15. they have investigated thermotical methods. The structure and morphology of the synthesized contrast agents were characterized by zeta potential sizer analysis (ZPS), X-Ray diffraction (XRD), Fourier-transform infrared (FT-IR), energy dispersive X-ray (EDX), ultraviolet–visible (UV–Vis) spectra, and scanning electron microscope (SEM). The experimental section was conducted and monitored by response surface methods (RSM), MTT, MIC, MBC, and cancer cytotoxic conversion assay. Antibiogram testing of NCs on Pseudomonas aeruginosa bacteria was successful and obtained MIC = 2 factors with less harmful effect. All experimental sections confirmed that our synthesized particles have potent antioxidant properties. Antibiogram testing revealed that NPS could kill P. aeruginosa and P. aeruginosa. A variety of synthetic conditions were done by diffusion emulsion method by varying parameters, the optimum state of DFA release Ga@DFA/FA/CS/PANI/PVA NPs (6 ml) with pH = 5.5, time = 3 h, NCs and DFA (3 mg), and achieved buffer (20 ml). DFA in Ga@DFA/FA/ CS/PANI/PVA was released and showed an absorption peak at 378 nm by applying a 300-rpm magnetic rate. In this report, Ga decreased the harmful effect on the human body.

Keywords: nanocapsules, technolgy, biology, nano

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Authors: M. Ghosh, A. Miroux, L. A. I. Kestens

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At molecular or micrometre scale, practically all materials are neither homogeneous nor isotropic. The concept of texture is used to identify the structural features that cause the properties of a material to be anisotropic. For metallic materials, the anisotropy of the mechanical behaviour originates from the crystallographic nature of plastic deformation, and is therefore controlled by the crystallographic texture. Anisotropy in mechanical properties often constitutes a disadvantage in the application of materials, as it is often illustrated by the earing phenomena during drawing. However, advantages may also be attained when considering other properties (e.g. optimization of magnetic behaviour to a specific direction) by controlling texture through thermo-mechanical processing). Nevertheless, in order to have better control over the final properties it is essential to relate texture with materials processing route and subsequently optimise their performance. However, up to date, few studies have been reported about the evolution of texture in 6061 aluminium alloy during warm processing (from room temperature to 250ºC). In present investigation, recrystallized 6061 aluminium alloy samples were subjected to tensile and plane strain compression (PSC) at room and warm temperatures. The gradual change of texture following both deformation modes were measured and discussed. Tensile tests demonstrate the mechanism at low strain while PSC does the same at high strain and eventually simulate the condition of rolling. Cube dominated texture of the initial rolled and recrystallized AA6061 sheets were replaced by domination of S and R components after PSC at room temperature, warm temperature (250ºC) though did not reflect any noticeable deviation from room temperature observation. It was also noticed that temperature has no significant effect on the evolution of grain morphology during PSC. The band contrast map revealed that after 30% deformation the substructure inside the grain is mainly made of series of parallel bands. A tendency for decrease of Cube and increase of Goss was noticed after tensile deformation compared to as-received material. Like PSC, texture does not change after deformation at warm temperature though. n-fibre was noticed for all the three textures from Goss to Cube.

Keywords: AA 6061, deformation, temperature, tensile, PSC, texture

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Authors: Mohsin Ejaz, Shiao-Wei Kuo

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The growing production and exploitation of fossil fuels have placed human society in serious environmental issues. As a result, it's critical to design efficient and eco-friendly energy production and storage techniques. Porous organic polymers (POPs) are multi-dimensional porous network materials developed through the formation of covalent bonds between different organic building blocks that possess distinct geometries and topologies. POPs have tunable porosities and high surface area making them a good candidate for an effective electrode material in energy storage applications. Herein, we prepared a fully benzoxazine-based porous organic polymers (TPA–DHTP–BZ POP) through sonogashira coupling of dihydroxyterephthalaldehyde (DHPT) and triphenylamine (TPA) containing benzoxazine (BZ) monomers. Firstly, both BZ monomers (TPA-BZ-Br and DHTP-BZ-Ea) were synthesized by three steps, including Schiff base, reduction, and mannich condensation reaction. Finally, the TPA–DHTP–BZ POP was prepared through the sonogashira coupling reaction of brominated monomer (TPA-BZ-Br) and ethynyl monomer (DHTP-BZ-Ea). Fourier transform infrared (FTIR) and solid-state nuclear magnetic resonance (NMR) spectroscopy confirmed the successful synthesis of monomers as well as POP. The porosity of TPA–DHTP–BZ POP was investigated by the N₂ absorption technique and showed a Brunauer–Emmett–Teller (BET) surface area of 196 m² g−¹, pore size 2.13 nm and pore volume of 0.54 cm³ g−¹, respectively. The TPA–DHTP–BZ POP experienced thermal ring-opening polymerization, resulting in poly (TPA–DHTP–BZ) POP having strong inter and intramolecular hydrogen bonds formed by phenolic groups and Mannich bridges, thereby enhancing CO₂ capture and supercapacitive performance. The poly(TPA–DHTP–BZ) POP demonstrated a remarkable CO₂ capture of 3.28 mmol g−¹ and a specific capacitance of 67 F g−¹ at 0.5 A g−¹. Thus, poly(TPA–DHTP–BZ) POP could potentially be used for energy storage and CO₂ capture applications.

Keywords: porous organic polymer, benzoxazine, sonogashira coupling, CO₂, supercapacitor

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