Security and Privacy Issues of Federated Learning

Federated Learning (FL) has emerged as a promising approach to address data privacy and confidentiality concerns by allowing multiple participants to construct a shared model without centralizing sensitive data. However, this decentralized paradigm introduces new security challenges, necessitating a comprehensive identification and classification of potential risks to ensure FL's security guarantees. This paper presents a comprehensive taxonomy of security and privacy challenges in Federated Learning (FL) across various machine learning models, including large language models. We specifically categorize attacks performed by the aggregator and participants, focusing on poisoning attacks, backdoor attacks, membership inference attacks, generative adversarial network (GAN) based attacks, and differential privacy attacks. Additionally, we propose new directions for future research, seeking innovative solutions to fortify FL systems against emerging security risks and uphold sensitive data confidentiality in distributed learning environments.Comment: 6 pages, 2 figure

An Analysis of Bugs In Persistent Memory Application

Over the years of challenges on detecting the crash consistency of non-volatile persistent memory (PM) bugs and developing new tools to identify those bugs are quite stretching due to its inconsistent behavior on the file or storage systems. In this paper, we evaluated an open-sourced automatic bug detector tool (i.e. AGAMOTTO) to test NVM level hashing PM application to identify performance and correctness PM bugs in the persistent (main) memory. Furthermore, our faithful validation tool able to discovered 65 new NVM level hashing bugs on PMDK library and it outperformed the number of bugs (i.e. 40 bugs) that WITCHER framework was able to identified. Finally, we will propose a Deep-Q Learning search heuristic algorithm over the PM-Aware search algorithm in the state selection process to improve the searching strategy efficiently.Comment: 8 pages, 4 figure

Decellularisation and characterisation of porcine bone-medial meniscus-bone

The meniscus in the knee functions to absorb shock and transmit load within the joint. Problems arise when the meniscus is injured or damaged as the meniscus’ healing potential is limited by the limited vascular supply extending only ~20% of the way through the mature meniscus. Current treatment options are only effective at abating further degeneration and osteoarthritis due to altered joint mechanics. Replacement of the meniscus has the potential to prevent the onset of osteoarthritis by restoring native joint mechanics. Here we aim to develop a decellularisation protocol for porcine medial meniscus with added bone blocks for easy fixation for use as a meniscal replacement. Menisci were decellularised using a low sodium dodecyl sulphate (SDS) method including freeze-thaw cycles, hypertonic, hypotonic and nuclease wash steps, as well as mechanical removal of cellular material. Decellularised menisci were then characterised histologically, immunohistochemically, biochemically and biomechanically for successful decellularisation and compared to native meniscus. Histology revealed the absence of whole cells and nuclei from meniscus and bone, while quantification of DNA revealed ~96% and ~91% removal of DNA from meniscus and bone, respectively. Immunohistochemical analysis showed retention of major structural collagens I, II and II; however there was complete removal of collagen IV and some loss of collagen VI. Hydroxyproline assay showed retention of collagen and the collagen content of native meniscus was 802.90 (± 52.95, 95% CL) mg.g-1 dry weight and for decellularised meniscus was 935.35 (± 18.03, 95% CL) mg.g-1 dry weight, however there was a complete loss of GAGs from the decellularised matrices as revealed by Safranin O staining and quantified using dimethyl methylene blue assay (23.49 ± 8.63 μg.mg-1 vs. 0.30 ± 0.47 μg.mg-1, 95% C.I.). There was also a 51% reduction in calcium content of the decellularised bone blocks when compared to native bone blocks. Material properties of meniscus were obtained using uniaxial tensile and indentation testing with no significant differences observed between native and decellularised groups under tension although greater deformation was seen for decellularised samples under compression. Unconfined compression of bone however revealed a significant decrease in the compressive modulus and strength of decellularised bone blocks. Differential scanning calorimetry revealed no significant differences in thermal stability between native and decellularised meniscus except for in the attachment region where collagen was mechanically manipulated prior to decellularisation. Magnetic resonance imaging (MRI) also revealed no gross differences between native and decellularised bone and meniscus. Extract and contact cytotoxicity assays were used to determine biocompatibility of decellularised bone-meniscus-bone and residual SDS content determined using radio-labelled 14C SDS. There was 0.289 μg.mg-1 of residual SDS in decellularised bone-meniscus-bone and assays showed no cytotoxicity to 3T3 and BHK cells. The immunogenic galactose-α-1,3-galactose epitope could not be detected in decellularised meniscus by immunohistochemistry. In conclusion, a protocol for the successful decellularisation of porcine bone-medial meniscus-bone has been developed which retains the structure and tensile properties of native meniscus and is non-cytotoxic. Further investigation is required to determine whether loss of mechanical strength in the bone will prevent effective fixation in vivo

Reasons behind the Drop out of Street Children from Non-formal Primary Education Program

The aim of this study is to find out the inner reasons of dropping out of street children from non-formal primary education program. With this study also we can have a figure of the lifestyle, needs and social conditions of street children. To have the findings of my study qualitative research method will be conducted. In accordance with the study objectives from the large areas only 1 authority member, 1 teacher, 5 admitted children and 5 dropped out children were selected as sample. I designed open-ended questionnaire and semi-structured interview to collect my data. The thematic analysis method was used for data analysis. I have a variation in findings because of using questionnaire for teacher and authority and interview for children. Moreover in commonly I can say the demographic conditions, lacking’s of parental care and guidance, lacking’s of Interest and awareness, lacking’s of facilities, lacking’s of economic support, effects of misguidances, lacking’s of proper relationship among program stuff with parents and children’s are major problems that disturbed the street children to continue their education. Considering the findings it can be recommended that increasing of education program or giving support with educational equipment is not enough to continue education in this marginal sector of society. It is more important to grow consciousness, make them understood the importance of education, giving them a link of better future through education and make a reliable environment between education program and parents-children. Keywords: Street Children, Non-formal Education Program, Drop ou

Ethnobotanical study of the family Marantaceae R. Br in Bangladesh Agricultural University Botanical Garden

The Marantaceae family is a diverse group of plants that has drawn the interest of scientists and researchers worldwide due to their distinctive morphological characteristics, ecological and economic relevance. The Bangladesh Agricultural University Botanical Garden is home to an abundance of Marantaceae species, making it a useful resource for examining the diversity and significance of this plant family. This present study was designed to survey and document the family Marantaceae with an overview of the family emphasizing its morphological, economic, and ethnobotanical relevance based on a literature review. During the study, we found 25 species (two of which have two varieties each) belonging to 8 genera of which Goeppertia contributed the most species, with 16, followed by Maranta with 4 (including varieties) and Thalia with 2; the remaining 5 genera each contributed one species. Our findings reveal the remarkable diversity and significance of Marantaceae plants in this region, highlighting the necessity for their conservation and protection

“Greener” chemical modification of cellulose nanocrystals via oxa-Michael addition with N-Benzylmaleimide

Surface modification of cellulose nanocrystals (CNCs) was conducted by an oxa-Michael addition of primary hydroxyl groups on the CNC surface with N-Benzylmaleimide (BnM). Six principles of green chemistry were used to obtain the hydrophobized CNC. Two catalytic approaches were used, a self-catalyzed reaction where alkyl sulfuric acid on the surface of the CNC was the catalyst, and a base-catalyzed approach using triethylamine (TEA). DMSO was chosen as reaction solvent due to its low cost, low toxicity and ability to disperse native CNC compared to other polar diprotic solvents. NMR and FTIR studies confirmed the successful modification of CNCs in both reaction routes. The TEA-catalyzed reaction showed a higher BnM conversion at 70 ​°C after 72 ​h (46 ​± ​2%) compared to the self-catalyzed reaction at 100 ​°C (24 ​± ​2%). Since BnM was added at a two-fold excess compared to superficial primary –OH groups, these had estimated conversions of 92% and 48%, for the base catalyzed and acid catalyzed routes, respectively. Zeta potential measurements suggest, the sulfate groups were retained after the modification reaction. AFM demonstrated no change in particle morphology after modification. Modified CNCs degraded at a higher temperature (390 ​± ​8 ​°C) when the reaction was catalyzed by TEA compared to native CNCs and the self-catalyzed product (220 ​± ​10 ​°C). Contact angle measurements demonstrated the increased hydrophobicity of the modified nanoparticles. Visual inspection and UV–vis spectroscopy demonstrated the modified CNCs had an increased affinity towards organic solvents like acetone, acetonitrile and toluene

Population Dynamics of Vibrios in Biotic Biofilm in the Aquatic Environment of Bangladesh

Abstract: The Vibrio sp. forming biofilm on biotic surface especially chitin and algae was investigated using artificial chitin and Anabaena variabilis from pure culture of laboratory and glued to plexiglass disc. The presence of culturable Vibrio spp. were investigated using cultural technique for TCBS agar medium after homogenization and physicochemical parameters were measured by standard techniques. The Pearson correlation coefficient applied by SPSS software. The results indicated that out of 13 sampling period, only V. cholerae O1 was isolated 7.7% sample while 30.8% samples were positive for V. cholerae non-O1, V. proteolyticus and V. mimicus from canal site. From pond ecosystem, all the chitin samples were negative for V. cholerae O1 but 15.4% were positive for V. cholerae non-O1 and V. proteolyticus and 30.8% samples were positive for V. mimicus. The biofilm formation is significantly correlated with the pH, DO and CO 2 concentration present of the corresponding water. This study indicates that biotic surface like chitin and algae could function to form biofilm and the water physicochemical parameters have the relationship with the Vibrio community present in the samples

Five-Class SSVEP Response Detection using Common-Spatial Pattern (CSP)-SVM Approach

Brain-computer interface (BCI) technologies significantly facilitate the interaction between physically impaired people and their surroundings. In electroencephalography (EEG) based BCIs, a variety of physiological responses including P300, motor imagery, movement-related potential, steady-state visual evoked potential (SSVEP) and slow cortical potential have been utilized. Because of the superior signal-to-noise ratio (SNR) together with quicker information transfer rate (ITR), the intentness of SSVEP-based BCIs is progressing significantly. This paper represents the feature extraction and classification frameworks to detect five classes EEG-SSVEP responses. The common-spatial pattern (CSP) has been employed to extract the features from SSVEP responses and these features have been classified through the support vector machine (SVM). The proposed architecture has achieved the highest classification accuracy of 88.3%. The experimental result proves that the proposed architecture could be utilized for the detection of SSVEP responses to develop any BCI applications