Screening of a Small Spherical Macroion by Oppositely Charged Flexible Polyelectrolyte

Electrostatic interactions play important roles in the assembly, the structureand the functions of many biological as well as soft matter systems. In the presence of a macro-ion in aqueous solution, oppositely charged molecules mobilize around it to screen out its electrostatic potential. In this paper, we focus on screening of small macroion by a flexible polyelectrolyteusing Monte-Carlo simulation. It is shown that the condensation of the polyelectrolyte around the macroion shows a first order phase transition from a dense to a dilute concentration of monomers. The width of the condensed region increases with stronger screening or with smaller macro-ion charges. For small macro-ion charge, or when the Coulomb interactions are strongly screened, no complexation between the polyelectrolyte and the macro-ion happens.Additionally, long polyelectrolyte protrudes both tails and loops from the macroion. This is quite different from the case of large macroions where only tails appear. Our results can be used to explain various experimental trends

Fed-LSAE: Thwarting Poisoning Attacks against Federated Cyber Threat Detection System via Autoencoder-based Latent Space Inspection

The significant rise of security concerns in conventional centralized learning has promoted federated learning (FL) adoption in building intelligent applications without privacy breaches. In cybersecurity, the sensitive data along with the contextual information and high-quality labeling in each enterprise organization play an essential role in constructing high-performance machine learning (ML) models for detecting cyber threats. Nonetheless, the risks coming from poisoning internal adversaries against FL systems have raised discussions about designing robust anti-poisoning frameworks. Whereas defensive mechanisms in the past were based on outlier detection, recent approaches tend to be more concerned with latent space representation. In this paper, we investigate a novel robust aggregation method for FL, namely Fed-LSAE, which takes advantage of latent space representation via the penultimate layer and Autoencoder to exclude malicious clients from the training process. The experimental results on the CIC-ToN-IoT and N-BaIoT datasets confirm the feasibility of our defensive mechanism against cutting-edge poisoning attacks for developing a robust FL-based threat detector in the context of IoT. More specifically, the FL evaluation witnesses an upward trend of approximately 98% across all metrics when integrating with our Fed-LSAE defense

Integrating of PLS-SEM and the Importance Performance Matrix Analysis to Exploring the Role of Provincial Competitiveness Index to Growth

Provincial competitiveness was one of the engines of growth under the institutional theory. The Vietnam Provincial Competitiveness Index (PCI) has been surveyed since 2005 to reflect the perceptions of local business environments, categorized into 10 sub-indices with 128 indicators. The current PCI has challenged the governance due to its broad construction. This study aimed to reconstruct the indicators in each PCI sub-index to be more specific for improving governance. The paper further explored the importance-of performance of both the PCI sub-index and its indicators to the provincial growth in Vietnam. Secondary data of 63 provinces during the period of 2017-2020 have been used with the employment of Exploratory Factor Analysis (EFA), Partial Least Square Structural Equation Model (PLS-SEM), and the extension of the importance-performance matrix analysis (IPMA). Our results showed the reliability and validity of 21 measured items under 5 PCI sub-indices. The findings confirmed the positive impact of the PCI index on growth. Moreover, the highest importance but lowest performance of SLO (law and order) was implied. SLA (land access and security of tenure), on the contrary, peaked the performance with the lowest importance. The importance of STC (time costs and regulatory compliance), SPA (proactive provincial leadership), and SLP (labor quality) has been ranked with the former sharing the highest priority while similar performance of the four sub-indices has been found. The results implied that the provincial authorities should prioritize their efforts to improve governance based on the importance-performance analysis of PCI sub-indices. Moreover, the importance and performance of each sub-index indicator reflected the great governance improvement with an average performance of 50%. However, special attention should be focused on vocational training, effective state officials, and legal support to the business due to their high importance but low performance

H2_{2}O2_{2} production in Lactobacillus strains isolated from the intestinal microbiome of healthy people

Lactobacillus sp. in the digestive tract are capable of producing H2O2 to inhibit the growth of harmful bacteria and balance the gut microflora. In this study, we have isolated 115 strains of Lactobacillus spp. from stool samples of healthy people in Ha Noi. Of the 50 tested Lactobacillus strains, 9 strains were capable of producing H2O2, of which the Lac.VFE-14 strain produced highly H2O2 with a concentration of 2.183 mM, followed by Lac.VFE-08 strains (2.081 mM) and Lac.VFE-04 (2.067 mM). All three strains grew well in MRS medium supplemented with bile salts or adjusted to low pH value. With 0.3% of bile salt, the survival rates of these 3 strains were 99%, 95% and 97%, respectively. At pH 3.0, after 3 hours of cultivation, the survival rates of the three strains were 98.54%, 94.15% and 95.27%, respectively. In addition, each of the cell-free culture supernatants of these three strains that inhibit the growth of S. aureus ATCC-23235. The inhibition zone diameters of the three strains were 19.0±1.0 mm, 14.0±1.0 mm and 11.7±1.3 mm, respectively. The results of 16S rRNA gene analyses showed that Lac.VFE-14, Lac.VFE-08 and Lac.VFE-04 had high similarity scores with L. plantarum ZZU 23 (100%), L. rhamnosus JCM 1136 (99%) and L. plantarum S7 (98.65%), respectively. This study indicates that all three strains have the potential to be used as probiotics in the future. 

Rectal Optical Markers for In-vivo Risk Stratification of Premalignant Colorectal Lesions.

Purpose: Colorectal cancer remains the second leading cause of cancer deaths in the U.S. despite being eminently preventable by colonoscopy via removal of premalignant adenomas. In order to more effectively reduce colorectal cancer mortality, improved screening paradigms are needed. Our group pioneered the use of low coherence enhanced backscattering (LEBS) spectroscopy to detect the presence of adenomas throughout the colon via optical interrogation of the rectal mucosa. In a previous ex-vivo biopsy study of 219 patients, LEBS demonstrated excellent diagnostic potential with 89.5% accuracy for advanced adenomas. The objective of the current cross-sectional study is to assess the viability of rectal LEBS in-vivo. Experimental Design: Measurements from 619 patients were taken using a minimally invasive 3.4 mm diameter LEBS probe introduced into the rectum via anoscope or direct insertion, requiring ~1 minute from probe insertion to withdrawal. The diagnostic LEBS marker was formed as a logistic regression of the optical reduced scattering coefficient μs∗ and mass density distribution factor D. Results: The rectal LEBS marker was significantly altered in patients harboring advanced adenomas and multiple non-advanced adenomas throughout the colon. Blinded and cross-validated test performance characteristics showed 88% sensitivity to advanced adenomas, 71% sensitivity to multiple non-advanced adenomas, and 72% specificity in the validation set. Conclusions: We demonstrate the viability of in-vivo LEBS measurement of histologically normal rectal mucosa to predict the presence of clinically relevant adenomas throughout the colon. The current work represents the next step in the development of rectal LEBS as a tool for colorectal cancer risk stratification

A new species of the Cyrtodactylus chauquangensis species group (Squamata, Gekkonidae) from Lao Cai Province, Vietnam

We describe a new species of the genus Cyrtodactylus based on five adult specimens from Bac Ha District, Lao Cai Province, northern Vietnam. Cyrtodactylus luci sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following morphological characteristics: medium size (SVL up to 89.5 mm); dorsal tubercles in 17–19 irregular transverse rows; ventral scales in 32–34 longitudinal rows at midbody; precloacal pores present in both sexes, 9 or 10 in males, 8 or 9 in females; 12–15 enlarged femoral scales on each thigh; femoral pores 9–12 in males, 5–10 in females; postcloacal tubercles 2–4; lamellae under toe IV 21–23; dorsal pattern consisting of 5 or 6 irregular dark bands, a thin neckband without V-shape or triangle shape in the middle, top of head with dark brown blotches; subcaudal scales transversely enlarged. Molecular phylogenetic analyses recovered the new species as the sister taxon to C. gulinqingensis from Yunnan Province, China, with strong support from all analyses and the two taxa are separated by approximately 8.87–9.22% genetic divergence based on a fragment of the mitochondrial ND2 gene. This is the first representative of Cyrtodactylus known from Lao Cai Province

CSA: Thực hành nông nghiệp thông minh với khí hậu ở Việt Nam

During the last five years, Vietnam has been one of the countries most affected by climate change. Severe typhoons, flooding, cold spells, salinity intrusion, and drought have affected agriculture production across the country, from upland to lowland regions. Fortunately for Vietnam, continuous work in developing climate-smart agriculture has been occurring in research organizations and among innovative farmers and entrepreneurs. Application of various CSA practices and technologies to adapt to the impact of climate change in agriculture production have been expanding. However, there is a need to accelerate the scaling process of these practices and technologies in order to ensure growth of agriculture production and food security, increase income of farmers, make farming climate resilient, and contribute to global climate change mitigation. This book aims to provide basic information to researchers, managers, and technicians and extentionists at different levels on what CSA practices and technologies can be up scaled in different locations in Vietnam

Caractérisation structurale du recrutement de la protéine JIP1 par la chaîne légère (KLC) de la kinésine1

AbstractKinesins are molecular motors involved in the intracellular transport of many cargos within the cell. Although the motility of kinesins is well understood, the molecular mechanisms underlying cargo recruitment are much less so.Kinesin1 plays various roles in neuronal cells, where it contributes to the spatial and temporal organization of many cellular components. It would play a role in various neurological pathologies, such as Alzheimer's disease. Understanding how kinesin1 recognizes and interacts with its cargos is important to decorticate its role, as well as that of its cargos, in normal and pathological cells. Kinesin1 is a heterotetramer consisting of two heavy chains (KHC) and two light chains (KLC), both of which are capable of recruiting cargo proteins. One of the first cargo proteins to have been identified is JIP1 (JNK-interacting protein 1) which is: (i) a scaffold protein for the signaling pathway of MAP kinases and (ii) an adaptor protein for transporting amyloid precursor protein (APP) responsible for Alzheimer's disease. In both cases, JIP1 regulates critical processes at the cell level, making it an interesting protein to study. Early studies have led to a better understanding of how JIP1 is recruited and transported by kinesin1. However, the detail of the interaction between KLC and JIP1 is not yet fully described and therefore understood.Objectives: My doctoral work aims at characterizing at the molecular level the interaction between KLC and JIP1. To do this, I had the following objectives: 1) to characterize the interaction domains of the two proteins alone, 2) to study the formation of the complex in solution by biophysical approaches, and 3) to determine the 3D structure of the complex by crystallography.Results: Initially, I characterized the TPR domain of KLC alone, contributing among others to the development of a molecular toolbox. I also participated in the determination of two crystallographic structures of the TPR domain of KLC1/2 that highlights the structural plasticity of the first helix of this domain (Nguyen et al, submitted). In a second step, I set up the conditions for the expression and purification of the PTB domain of JIP1 and carry out the structural characterization of this domain in solution. Although this domain of JIP1 is not necessary for interaction with KLC, I studied the impact of its presence on recruitment by KLC. Finally, I characterized the recruitment of JIP1 by KLC by confirming a number of information on the interaction between the KLC-TPR and the C-terminal region (Cter) of JIP1 at the molecular level. The numerous crystallization tests that I carried out did not make it possible to obtain crystals of the KLC: JIP1 complex. However, I was able to precisely map the interaction zone of JIP1-Cter with the KLC-TPR domain using the various KLC tools available by determining by ITC their affinity with JIP1-Cter (Nguyen et al., In preparation ).Conclusion: Thus, my PhD work allowed to better understand 1) the structural versatility of the KLC-TPR domain, 2) the impact of the JIP1-PTB domain for its KLC recruitment, and 3) the interaction mode of JIP1 by KLC . On the basis of these data, I will discuss the structural basis of the mode of binding of KLC with JIP1 and compare it with that of KLC with WD-motif cargo, such as SKIP and Alcadein-α.RésuméLes kinésines sont des moteurs moléculaires impliqués dans le transport intracellulaire de nombreux cargos au sein de la cellule. Bien que la motilité des kinésines soit bien comprise, les mécanismes moléculaires à la base du recrutement des cargos le sont beaucoup moins.La kinésine1 joue divers rôles dans les cellules neuronales, où elle contribue à l’organisation spatiale et temporelle de nombreux composants cellulaires. Elle jouerait un rôle dans différentes pathologies neurologiques, comme la maladie d’Alzheimer. Comprendre comment la kinésine1 reconnaît et interagit avec ses cargos est important pour déterminer son rôle, ainsi que celui de ses cargos, au niveau du fonctionnement des cellules normales et pathologiques. La kinésine1 est un hétérotétramère constitué de deux chaînes lourdes (KHC) et de deux chaînes légères (KLC) toutes deux étant capables de recruter des protéines cargos. L’une des premières protéines cargos à avoir été identifiée est JIP1 (JNK-interacting protein 1) qui est, entre autres: (i) une protéine d’échafaudage pour la voie de signalisation des MAP kinases et (ii) une protéine adaptatrice pour le transport de la protéine précurseur de l’amyloïde (APP) responsable de la maladie d’Alzheimer. Dans les deux cas, JIP1 régule des processus critiques au niveau de la cellule, ce qui en fait une protéine intéressante à étudier. Des premières études ont permis de mieux comprendre comment JIP1 est recrutée et transportée par la kinésine1. Cependant, le détail de l’interaction entre KLC et JIP1 n’est pas encore complètement décrit et donc compris.Objectifs : Mon travail de doctorat vise à caractériser au niveau moléculaire l’interaction entre KLC et JIP1. Pour ce faire, j’avais pour objectifs : 1) de caractériser les domaines d’interaction des deux protéines seules, 2) d’étudier la formation du complexe en solution par des approches biophysiques et 3) de déterminer la structure 3D du complexe par cristallographie.Résultats : Dans un premier temps, j’ai caractérisé le domaine TPR de KLC seul en contribuant entre autres au développement d’une boite à outils moléculaires. J’ai aussi participé à la détermination de deux structures cristallographiques du domaine TPR de KLC1/2 permettant de mettre en évidence la plasticité structurale de la 1ère hélice de ce domaine (Nguyen et al, soumis). Dans un second temps, j’ai mis en place les conditions d’expression et de purification du domaine PTB de JIP1 et mener la caractérisation structurale de ce domaine en solution. Bien que ce domaine de JIP1 ne soit pas nécessaire pour l’interaction avec KLC, j’ai pu étudier l’impact de sa présence au niveau du recrutement par KLC. Finalement, j’ai caractérisé le recrutement de JIP1 par KLC en confirmant tout d’abord un certain nombre d’information sur l’interaction entre le domaine TPR de KLC et la région C-terminale (Cter) de JIP1 au niveau moléculaire. Les nombreux essais de cristallisation que j’ai menés n’ont pas permis d’obtenir des cristaux du complexe KLC:JIP1. J’ai cependant pu cartographier de façon précise la zone d’interaction de JIP1-Cter avec le domaine TPR de KLC en employant les différents outils de KLC disponibles pour déterminer par calorimétrie leur affinité avec JIP1-Cter (Nguyen et al., en préparation).Conclusion : Ainsi, mon travail de doctorat a permis de mieux comprendre 1) la versatilité structurale du domaine TPR de KLC, 2) l’impact du domaine PTB de JIP1 pour son recrutement par KLC et 3) le mode d’interaction de JIP1 par KLC. Sur la base de ces données, je discuterai les bases structurales du mode d’interaction de KLC avec JIP1 et le comparerai à celui de KLC avec les cargos à motif WD, comme SKIP et Alcadéine-α

Structural characterization of JIP1 recruitment by kinesin1 light chain (KLC)

RésuméLes kinésines sont des moteurs moléculaires impliqués dans le transport intracellulaire de nombreux cargos au sein de la cellule. Bien que la motilité des kinésines soit bien comprise, les mécanismes moléculaires à la base du recrutement des cargos le sont beaucoup moins.La kinésine1 joue divers rôles dans les cellules neuronales, où elle contribue à l’organisation spatiale et temporelle de nombreux composants cellulaires. Elle jouerait un rôle dans différentes pathologies neurologiques, comme la maladie d’Alzheimer. Comprendre comment la kinésine1 reconnaît et interagit avec ses cargos est important pour déterminer son rôle, ainsi que celui de ses cargos, au niveau du fonctionnement des cellules normales et pathologiques. La kinésine1 est un hétérotétramère constitué de deux chaînes lourdes (KHC) et de deux chaînes légères (KLC) toutes deux étant capables de recruter des protéines cargos. L’une des premières protéines cargos à avoir été identifiée est JIP1 (JNK-interacting protein 1) qui est, entre autres: (i) une protéine d’échafaudage pour la voie de signalisation des MAP kinases et (ii) une protéine adaptatrice pour le transport de la protéine précurseur de l’amyloïde (APP) responsable de la maladie d’Alzheimer. Dans les deux cas, JIP1 régule des processus critiques au niveau de la cellule, ce qui en fait une protéine intéressante à étudier. Des premières études ont permis de mieux comprendre comment JIP1 est recrutée et transportée par la kinésine1. Cependant, le détail de l’interaction entre KLC et JIP1 n’est pas encore complètement décrit et donc compris.Objectifs : Mon travail de doctorat vise à caractériser au niveau moléculaire l’interaction entre KLC et JIP1. Pour ce faire, j’avais pour objectifs : 1) de caractériser les domaines d’interaction des deux protéines seules, 2) d’étudier la formation du complexe en solution par des approches biophysiques et 3) de déterminer la structure 3D du complexe par cristallographie.Résultats : Dans un premier temps, j’ai caractérisé le domaine TPR de KLC seul en contribuant entre autres au développement d’une boite à outils moléculaires. J’ai aussi participé à la détermination de deux structures cristallographiques du domaine TPR de KLC1/2 permettant de mettre en évidence la plasticité structurale de la 1ère hélice de ce domaine (Nguyen et al, soumis). Dans un second temps, j’ai mis en place les conditions d’expression et de purification du domaine PTB de JIP1 et mener la caractérisation structurale de ce domaine en solution. Bien que ce domaine de JIP1 ne soit pas nécessaire pour l’interaction avec KLC, j’ai pu étudier l’impact de sa présence au niveau du recrutement par KLC. Finalement, j’ai caractérisé le recrutement de JIP1 par KLC en confirmant tout d’abord un certain nombre d’information sur l’interaction entre le domaine TPR de KLC et la région C-terminale (Cter) de JIP1 au niveau moléculaire. Les nombreux essais de cristallisation que j’ai menés n’ont pas permis d’obtenir des cristaux du complexe KLC:JIP1. J’ai cependant pu cartographier de façon précise la zone d’interaction de JIP1-Cter avec le domaine TPR de KLC en employant les différents outils de KLC disponibles pour déterminer par calorimétrie leur affinité avec JIP1-Cter (Nguyen et al., en préparation).Conclusion : Ainsi, mon travail de doctorat a permis de mieux comprendre 1) la versatilité structurale du domaine TPR de KLC, 2) l’impact du domaine PTB de JIP1 pour son recrutement par KLC et 3) le mode d’interaction de JIP1 par KLC. Sur la base de ces données, je discuterai les bases structurales du mode d’interaction de KLC avec JIP1 et le comparerai à celui de KLC avec les cargos à motif WD, comme SKIP et Alcadéine-α.AbstractKinesins are molecular motors involved in the intracellular transport of many cargos within the cell. Although the motility of kinesins is well understood, the molecular mechanisms underlying cargo recruitment are much less so.Kinesin1 plays various roles in neuronal cells, where it contributes to the spatial and temporal organization of many cellular components. It would play a role in various neurological pathologies, such as Alzheimer's disease. Understanding how kinesin1 recognizes and interacts with its cargos is important to decorticate its role, as well as that of its cargos, in normal and pathological cells. Kinesin1 is a heterotetramer consisting of two heavy chains (KHC) and two light chains (KLC), both of which are capable of recruiting cargo proteins. One of the first cargo proteins to have been identified is JIP1 (JNK-interacting protein 1) which is: (i) a scaffold protein for the signaling pathway of MAP kinases and (ii) an adaptor protein for transporting amyloid precursor protein (APP) responsible for Alzheimer's disease. In both cases, JIP1 regulates critical processes at the cell level, making it an interesting protein to study. Early studies have led to a better understanding of how JIP1 is recruited and transported by kinesin1. However, the detail of the interaction between KLC and JIP1 is not yet fully described and therefore understood.Objectives: My doctoral work aims at characterizing at the molecular level the interaction between KLC and JIP1. To do this, I had the following objectives: 1) to characterize the interaction domains of the two proteins alone, 2) to study the formation of the complex in solution by biophysical approaches, and 3) to determine the 3D structure of the complex by crystallography.Results: Initially, I characterized the TPR domain of KLC alone, contributing among others to the development of a molecular toolbox. I also participated in the determination of two crystallographic structures of the TPR domain of KLC1/2 that highlights the structural plasticity of the first helix of this domain (Nguyen et al, submitted). In a second step, I set up the conditions for the expression and purification of the PTB domain of JIP1 and carry out the structural characterization of this domain in solution. Although this domain of JIP1 is not necessary for interaction with KLC, I studied the impact of its presence on recruitment by KLC. Finally, I characterized the recruitment of JIP1 by KLC by confirming a number of information on the interaction between the KLC-TPR and the C-terminal region (Cter) of JIP1 at the molecular level. The numerous crystallization tests that I carried out did not make it possible to obtain crystals of the KLC: JIP1 complex. However, I was able to precisely map the interaction zone of JIP1-Cter with the KLC-TPR domain using the various KLC tools available by determining by ITC their affinity with JIP1-Cter (Nguyen et al., In preparation ).Conclusion: Thus, my PhD work allowed to better understand 1) the structural versatility of the KLC-TPR domain, 2) the impact of the JIP1-PTB domain for its KLC recruitment, and 3) the interaction mode of JIP1 by KLC . On the basis of these data, I will discuss the structural basis of the mode of binding of KLC with JIP1 and compare it with that of KLC with WD-motif cargo, such as SKIP and Alcadein-α