Academic research can make significant contributions to policymakers and other researchers interested in building evidence-based knowledge. However, it is difficult for students to imagine how their ...research can effectively contribute to social change while respecting curriculum requirements, especially with regard to maintaining methodological and scientific rigour and the validity demanded by academic standards. The rich work and experience of Aziz Choudry contribute directly to overcoming these obstacles and challenges, as he conceptualised research and knowledge production as an activity not exclusive to academia or research institutes, but widely present within social organisations and social movements.
In this paper, we reflect on our experiences of conducting research within community organisations as graduate scholars. Building on our respective research experience, including popular education in our research practice, we highlight how popular education spaces offer opportunities for scholars to disseminate their research results and contribute to raising awareness, but also to achieve the standards of intellectual rigour expected by academia. The main goal of this paper is to position the field of social movement learning and knowledge production as key for students who want to develop engaged and relevant research.
Musculoskeletal model is a useful tool to evaluate the complex biomechanical problems, simulate and evaluate the injuries, estimate the muscle-tendon forces, and joint the torques during motion and ...predict the effects of orthopedic surgeries. Moreover, the musculoskeletal model is a rich source of information to develop robotics exoskeleton aiming to restore the normal gait after some injuries. This paper presents a full musculoskeletal model in an open-source framework to perform the biomechanical analysis of the human lower limb in order to simulate both healthy and pathological gait; 14 bones, 88 Hill-type muscle-tendon segments, ten ligament segments for each knee, and six joints for each lower limb were modeled. The model allows us to simulate different injuries of the lower limb, such as ictus, stroke, and so on, by sending different signal profiles to muscle-tendon segments, emulating the functional electrical stimulation (FES). At the same time, forces and torques could be computed for muscles and joints. Hence, the proposed model can be suitable not only to perform a complete biomechanical analysis for medical purposes but also for the exoskeleton controller design and actuators dimensioning. In order to validate the model, it was exported to Simulink environment to simulate the joints range of motion, muscle moment arm, and joint torque, and then, these data were compared with the medical literature. All simulations results show that the data from the model are according to the previously published works. Furthermore, the model was validated using the real data obtained by our own gait capture system and by CODA motion software for normal and pathological gait. Finally, the goodness-of-fit of our model was assessed using the root mean square error (RMSE) and the normalized mean square error (NMSE); the values of these indices suggest that the model estimated the kinematics and kinetics parameters of healthy and pathological gait successfully.
In this work, a proposal to quantify the security gap between Encryption-then-Compression (EtC) systems and the Substitution-Permutation Network (SPN) is presented. A new image transmission system ...for JPEG files, EtC with Quantization before Transformation (EtCQT) was developed to test the proposed comparison. SPN is a well-known model used for security comparisons but is incompatible with the lossy compression required for saving storage while transmitting images. EtC systems have been designed considering compression performance rather than security, and in most developments in this field, only compression parameters are evaluated. The proposed evaluation was carried out with the metrics used for SPN, and the results showed the weaknesses of the EtC systems by quantifying them. This could help to improve security while keeping compatibility in future designs. EtCQT is based on the EtC scheme combined with block scrambling, with a quantization step instead of a permutation in the color transformation stage. The impact of this modification is an important reduction of the original pixel values in the color distribution that increases the information security, preserving only <inline-formula> <tex-math notation="LaTeX">16.\overline {6}\% </tex-math></inline-formula> of the initial values compared to 50% in other EtC systems.
Some images that contain sensitive information and travel through the network require security. Therefore, a symmetric cryptosystem that encrypts images and resists known attacks is developed. ...Subsequently, in this work, an encryption algorithm known as Image Cipher utilizing Lorenz equation and a Bijective Function—ICLEBF are proposed. In the proposal, the Lorenz equations and the Bijective function are used to generate boxes, the permutation, and schedule keys, considering that all these elements are different in each encryption process. The encryption procedure consists of 14 rounds, where a different box is applied in each round. In this type of algorithm, the impact of quantum computers will be less forceful and can be useful for that epoch. On the other hand, the quality of the encrypted images and the loss of sharpness in decoded images with damage are measured. In addition, an attack from five types of noise (one of which is a developed proposal) is carried out by applying it to encrypted images. Finally, the results of the proposed ICLEBF are compared with other recent image encryption algorithms, including the Advanced Encryption Standard. As a result, this proposal resists known attacks and others that the current standard does not support.
Cet article explore le rôle des agences d’emploi temporaire à Montréal dans l’exploitation de la main-d’oeuvre immigrante et la relation de ces agences avec le racisme systémique au Québec. ...L’hypothèse qui guide cet article est que la dérégulation des agences et les vulnérabilités produites par les statuts migratoires des travailleurs sont des facteurs qui font du travail intérimaire une composante du racisme systémique sur le marché du travail québécois. Nous cherchons ici à analyser si le régime de travail intérimaire s’articule avec la discrimination fondée sur le statut d’immigration et le racisme systémique. Dans cet article, j’aborde d’abord ce qu’est le travail intérimaire et ses effets sur les conditions de travail en soulignant l’importance de l’utilisation de la main-d’oeuvre immigrante. Par la suite, je revisite les schémas historiques de discrimination raciale au Canada et au Québec, puis je présente et analyse certaines expériences d’abus et de discrimination en milieu de travail ainsi que certaines pratiques d’agence dans la gestion des vulnérabilités des immigrants. Ces analyses sont tirées d’entrevues avec 42 travailleurs immigrants ainsi que d’entretiens avec des organisateurs du Centre des travailleurs et travailleuses immigrants (CTI) et de l’Association des travailleurs et travailleuses d’agences de placement de Montréal (ATTAP).
The negative–positive transformation (NPT) is a widely employed technique for encrypting images on pixel blocks, commonly integrated into cryptosystems compatible with compression algorithms. The ...existing literature on NPT analysis can be categorized into two types: theoretical analyses with results that apply to any image, primarily focused on compression compatibility, and numerical analyses that report empirical results from specific images, some without explaining the causes of the security results, while others are only related to the compression performance. Consequently, there is a significant gap in understanding the implications of applying the NPT for data protection. For that reason, this paper conducts a theoretical statistical analysis, presenting, demonstrating, and verifying six theorems to understand the security contributions of NPT. Two theorems examine the shape of the image histogram and the scatter plot of adjacent pixels after the NPT application. The subsequent four theorems explore the influence of NPT on the mean, variance, covariance, and correlation within each pixel block. The findings indicate that the NPT generates images with symmetrical histograms, the correlation of pixel blocks remains invariant, and distinct vertical and horizontal reflections manifest on the scatter plot. These theorems are verified by encrypting the Lena image with four pixel-block sizes. The histogram symmetry passed the goodness-of-fit test at a significance level of 5%, revealing consistent results. The correlation of pixel blocks remained unchanged, and the scatter plot exhibited an x-shaped pattern. Therefore, as the NPT alone does not achieve desirable encryption results, such as uniform histograms, scatter plots, and decreasing correlation, cryptosystems should complement it with additional techniques.
The superconductivity observed in boron-doped diamond is discussed from the point of view of the phonon-driven BCS theory. It is shown that electron-phonon interaction is particularly strong in ...diamond. Othersemiconductors possibly exhibiting superconductivity are broughtto the fore. Related evidence for strong electron-phonon interaction in semiconductors containing carbon, nitrogen and oxygen is presented.
This paper shows the dynamic modeling and design of a passivity-based controller for the RV-3SB robot. Firstly, the dynamic modeling of a Mitsubishi RV-3SB robot is conducted using Euler–Lagrange ...formulation in order to obtain a decoupled dynamic model, considering the actuator orientation besides the position of the analyzed robot. It is important to remark that the dynamic model of the RV-3SB robot is conducted based on kinematic model obtention, which is developed by the implementation of screw theory. Then, the passivity-based controller is obtained by separating the end effector variables and the actuator variables by making an appropriate coordinate transformation. The passivity-based controller is obtained by selecting an appropriate storage function, and by using Lyapunov theory, the passivity-based control law is obtained in order to drive the error variable, which is the difference between the measured end effector position variable and the desired end effector position variable. The passivity-based controller makes the error variable reach the origin in finite time, taking into consideration the dissipation properties of the proposed controller in order to stabilize the desired end effector position. A numerical simulation experiment is performed in order to validate the theoretical results obtained in this research. Using numerical experimentation, it is verified that the proposed control strategy is efficient and effective in driving the error variable to the origin in comparison with other modified techniques found in the literature. Finally, an appropriate discussion and conclusion of this research study are provided.
BackgroundEffective cancer therapy is still a challenge, and there is a strong need for remarkable therapeutic outcomes. Among the most compelling new cancer approaches are targeted therapies, ...specialized cancer vaccines (MTI, MVA),100-mer peptide, and immune checkpoint blocking (ICI) antibodies association.1 Our initial studies showed that established tumors in mice derived from tumor cell lines expressing a tumor-associated form of MUC1 (TA-MUC1), a cell-surface antigen that presents a tumor-specific glycan structure that is hidden on normal cells, treated with a combination of MTI and ICI, reduce tumor growth and extend survival compared to either agent alone.2 We are optimizing the conditions for tumor growth kinetics on the human MUC1 transgenic mice (hMUC1.tg), an immune-competent in vivo model, to evaluate a vaccine regiment that can produce a broad spectrum of anti-tumor immune responses.MethodsTwo mouse PDCA cell lines (KCM-Luc, Panc02.MUC1) were characterized for a high MUC1 and PD-L1 expression and for tumor growth kinetics in MUC1.tg mice model (N= 8, females and males). The cells were injected subcutaneously in the right flank of the hMUC1.tg mice. The tumor size was measured with calipers once a week with routine surveillance of body weight until the tumor reached 20x20mm3. The serum was collected from the tail at day 7. The survival interval was analyzed, and samples (serum, tumor, spleen, and lymph nodes) were collected for further analysis. The efficacy was measured as reduction or clearance of tumors and survival, the vaccination regimen for KCM-Luc and Panc02.MUC1 are described below (table 1 and 2).ResultsWe characterized the cells for high levels of MUC1 and PD-L1 expression (>70%). KCM-Luc the best growth kinetics and vaccine efficacy was with 125x103 cells/mice. The combination of MVA-MUC1 with 100-mer and anti-PD1 showed better results and increased animal survival than the non-treated group (figure 1). However, the growth kinetics do not allowed the complete vaccine regiment evaluation, so we used Panc02.MUC1 cell line,3 showed the best tumor growth kinetics with 0.5x106 cells/mice (figure 2), no significative changes in the body weight, and effective anti-PD-L1 results in prolonged animal survival and slow tumor growth were reported. These results are consistent with previous researchers4 and will allow the start of the new vaccination regimen (table 2).ConclusionsThose are initial data to optimize the conditions for the next experiments with vaccine evaluation associated with adjuvant drugs to understand the mechanisms of protection investigation cellular and antibody immune responses.AcknowledgementsThe authors gratefully acknowledge UNC at Charlotte and GeoVax company.ReferencesAli A, Chianese U, Papulino C, Toraldo A, Abakar MEA, Passaro E, Cennamo R, Del Gaudio N, Altucci L, Benedetti R. Metabolic pathways as a novel landscape in pancreatic ductal adenocarcinoma. Cancers 2022;14:3799. https://doi.org/10.3390/cancers 14153799Pinku Mukherjee, Gargi D Basu, Teresa L Tinder, Durai B Subramani, Judy M Bradley, Million Arefayene, Todd Skaar, Giovanni De Petris. Progression of pancreatic adenocarcinoma is significantly impeded with a combination of vaccine and COX-2 inhibition1. J Immunol 1 January 2009;182(1):216–224. https://doi.org/10.4049/jimmunol.182.1.216Mehla K, Tremayne J, Grunkemeyer JA, O’Connell KA, Steele MM, Caffrey TC, Zhu X, Yu F, Singh PK, Schultes BC, Madiyalakan R, Nicodemus CF, Hollingsworth MA. Combination of mAb-AR20.5, anti-PD-L1 and PolyICLC inhibits tumor progression and prolongs survival of MUC1.Tg mice challenged with pancreatic tumors. Cancer Immunol Immunother. 2018 Mar;67(3):445–457. doi: 10.1007/s00262-017-2095-7. Epub 2017 Dec 4. PMID: 29204701; PMCID: PMC7108804.Sagiv-Barfi I, Kohrt HE, Czerwinski DK, Ng PP, Chang BY, Levy R. Therapeutic antitumor immunity by checkpoint blockade is enhanced by ibrutinib, an inhibitor of both BTK and ITK. Proc Natl Acad Sci U S A. 2015 Mar 3;112(9):E966–72. doi: 10.1073/pnas.1500712112. Epub 2015 Feb 17. PMID: 25730880; PMCID: PMC4352777.Ethics ApprovalThis study was approved by the protocol institution’s Ethics Board, IACUC (Institutional Animal Care & Use Committee) at the University of North Carolina at Charlotte (UNCC), approval number 22-018.Abstract 1147-H Table 1Evaluation of vaccine regimens to treat pancreatic tumors immunization and sampling schedule for KCM-Luc tumor cells vaccination regimentAbstract 1147-H Figure 1KCM-Luc tumor growth kinetics and vaccination regiment evaluationAbstract 1147-H Table 2Immunization and sampling schedule Panc02.MUC1 tumor cells vaccination regimentAbstract 1147-H Figure 2Panc02.MUC1 tumor growth kinetics evaluation
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