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The primary objective of this research work is to generate a dynamically balanced gait for the 16-DOF biped robot while crossing an obstacle using the concept of the zero moment point (ZMP). Also, the authors discussed both the theoretical justification and its practical feasibility on real biped robot. Initially, the position and orientation of the biped robot were obtained with the help of forward kinematics while crossing the obstacle. Later on, various joint angles of the biped robot were calculated using the inverse kinematics approach. Further, the Lagrange-Euler formulation approach was employed for evaluating the dynamics of the biped robot. To generate the smooth gait of the biped robot, a cubic polynomial equation has been assigned for foot and wrist trajectories in the sagittal plane and hip trajectories in the horizontal plane. This integration allows the robot to cross the obstacles while maintaining dynamic balance, marking a significant advancement while crossing the obstacle with a height and width equal to 50 mm, which is 16.10% of the length of the robot's leg. While crossing the obstacle, the gait of the biped robot has been considered in three stages, such as landing the foot on the obstacle, landing the foot on the ground away from the obstacle by one leg and crossing over the obstacle by another leg. A simulation study has been conducted on MATLAB to verify the dynamically balanced gait while crossing the obstacle. Finally, the generated gait angles are fed into the real 16-DOF biped robot developed by the Robotics Lab at MANIT Bhopal. It has been observed that the generated gait at three stages is more dynamically balanced while crossing the obstacle. [ABSTRACT FROM AUTHOR]

Clinical orthopedics continuously aims to improve methods for bone formation. Clinical applications where bone formation is necessary include critical long bone defects in orthopedic trauma or tumor patients. Though some biomaterials combined with autologous stem cells significantly improve bone repair, critical-size damages are still challenged with the suitable implantation of biomaterials and donor cell survival. Extracellular matrix (ECM) is the fundamental structure in tissues that can nest and nourish resident cells as well as support specific functions of the tissue type. ECM also plays a role in cell signaling to promote bone growth, healing and turnover. In the last decade, the use of bone-derived ECMs or ECM-similar biomaterials have been widely investigated, including decellularized and demineralized bone ECM. In this article, we reviewed the current productions and applications of decellularized and demineralized bone matrices. We also introduce the current study of whole limb decellularization and recellularization. Article highlights The extracellular matrix (ECM) of bone has promoted bone growth, healing and turnover, and maintains its strength through the inorganic matrix. Demineralized bone matrix (DBM) is the allograft bone with only the organic compounds of ECM and decellularized bone matrix (dECM) is allograft or xenograft bone with removed nuclear material but maintenance of the native ECM components. Both are studied in clinical orthopedics. Basic science of DBM Optimizing the amounts of collagen and hydroxyapatite in DBM can maximize hypoxia-inducible factor-1a (HIF-1a) mediated angiogenesis and stromal cell-derived factor-1a (SDF-1a) mediated recruitment of MSCs to sites of bone injury in bone healing. Cortical bone demineralization is completed by immersing the sample in acid and making bone matrix growth factors (BMP-2, BMP-7) bioavailable. Decellularization of bone involves physical, chemical and/or enzymatic techniques to strip bone of cellular components and leave behind noncellular ECM. Clinical applications of DBM DBM has been successfully used in multiple spine surgeries, in the treatment of bone cysts, long bone nonunions and small foot bone defects. DBM has been studied in relation to tibial lengthening revealing enhanced consolidation. Use of decellularized whole limbs The decellularization of entire limbs has been investigated as potential graft material. A proof-of-concept study has demonstrated the decellularization of an entire upper extremity of a human cadaver, including bone tissue. Conclusion DBM is commonly used to treat recipient bone defects but is less mechanically stable due to the loss of hydroxyapatite. dECM retains the ECM structure and should be explored further in the future. Future implications dECM should be used in human trials. Recellularization of decellularized entire limbs should be further explored in animal models. [ABSTRACT FROM AUTHOR]

Deep Chlorophyll Maxima (DCMs) are ubiquitous in low‐latitude oceans, and of recognized biogeochemical and ecological importance. DCMs have been observed in the Southern Ocean, initially from ships and recently from profiling robotic floats, but with less understanding of their onset, duration, underlying drivers, or whether they are associated with enhanced biomass features. We report the characteristics of a DCM and a Deep Biomass Maximum (DBM) in the Inter‐Polar‐Frontal‐Zone (IPFZ) south of Australia derived from CTD profiles, shipboard‐incubated samples, a towbody, and a BGC‐ARGO float. The DCM and DBM were ∼20 m thick and co‐located with the nutricline, in the vicinity of a subsurface ammonium maximum characteristic of the IPFZ, but ∼100 m shallower than the ferricline. Towbody transects demonstrated that the co‐located DCM/DBM was broadly present across the IPFZ. Large healthy diatoms, with low iron requirements, resided within the DCM/DBM, and fixed up to 20 mmol C m−2 d−1. The BGC‐ARGO float revealed that DCM/DBM persisted for >3 months. We propose a dual environmental mechanism to drive DCM/DBM formation and persistence within the IPFZ: sustained supply of both recycled iron within the subsurface ammonium maxima, and upward silicate transport from depth. DCM/DBM cell‐specific growth rates were considerably slower than those in the overlying mixed layer, implying that phytoplankton losses such as herbivory are also reduced, possibly because of heavily silicified diatom frustules. The light‐limited seasonal termination of the observed DCM/DBM did not result in a "diatom dump", rather ongoing diatom downward export occurred throughout its multi‐month persistence. Plain Language Summary: Deep Chlorophyll and Deep Biomass Maxima are typically observed in the low latitude oceans where they contribute to regional ecology and biogeochemistry. They are cryptic features not observable from satellites. They are being more frequently observed in the Southern Ocean due to increased deployment of robotic profilers. The mechanisms that lead to their formation are not well understood in the Southern Ocean. Little is known about their seasonality or biogeochemical role. We use multiple observational platforms to address these issues. Key Points: Coupled Deep Chlorophyll Maxima (DCM) and Deep Biomass Maxima (DBM) subsurface features in the polar Southern Ocean are formed while mixed layer chlorophyll is not depletedThese subsurface features are dominated by large diatoms, and persist for around 3 months before declining due to low light conditionsDCM/DBMs photosynthetically fix low levels of carbon but their longevity results in a substantial amount of carbon export to depth [ABSTRACT FROM AUTHOR]

Background Child growth and development are profoundly influenced by postnatal nutrition. Despite global efforts, malnutrition and obesity remain pressing issues. In Turkey, child stunting and maternal obesity are significant concerns, with emerging cases of double burden of malnutrition (DBM), where households face both undernutrition and obesity. Aims and objectives This study aims to determine the prevalence of DBM at the household level in Manisa, Turkey, and identify associated factors. Objectives include assessing the nutritional status of children and mothers and exploring sociodemographic and lifestyle factors related to DBM. Methods A cross-sectional study was conducted with 385 women and their children (0-5 years) from two family health centers. Data were collected via interviews and anthropometric measurements. Descriptive statistics and logistic regression analyses were performed using Statistical Product and Service Solutions (SPSS, version 23.0; IBM SPSS Statistics for Windows, Armonk, NY) to evaluate DBM prevalence and associated factors. Results The study highlights that 63.2% of mothers are overweight or obese, with significant associations with lower education levels, inadequate health insurance, and financial instability. Among children, 7.8% were obese and 15.1% were stunted, with significant links to age, birth weight, and breastfeeding practices. The double DBM, where both maternal obesity and child malnutrition coexist, was present in 15.9% of households. Migration patterns, economic challenges, and price increases affected dietary choices and overall health. Notably, birth order and type of health insurance were significant predictors of the double DBM. Conclusion The study underscores the interplay between socioeconomic factors and nutritional status in both mothers and children. High rates of maternal obesity and child malnutrition, including stunting and obesity, are linked to education, income, and health insurance status. Addressing these socio-economic disparities and improving access to healthcare and nutrition is essential to mitigate the double DBM and enhance overall health outcomes., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Ethical Committee of Manisa Celal Bayar University issued approval 14538. This study employed a cross-sectional design, with data collected through face-to-face questionnaire surveys and anthropometric measurements. The research was conducted in compliance with ethical standards, with approval obtained from the Ethical Committee of Manisa Celal Bayar University prior to the commencement of the study. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Longwill et al.)