The role of autophagy in osteoclast differentiation and bone resorption function

Autophagy is an evolutionary conserved and highly regulated recycling process of cellular wastes. Having a housekeeping role, autophagy through the digestion of domestic cytosolic organelles, proteins, macromolecules, and pathogens, eliminates unnecessary materials and provides nutrients and energy for cell survival and maintenance. The critical role of autophagy and autophagy-related proteins in osteoclast differentiation, bone resorption, and maintenance of bone homeostasis has previously been reported. Increasing evidence reveals that autophagy dysregulation leads to alteration of osteoclast function and enhanced bone loss, which is associated with the onset and progression of osteoporosis. In this review, we briefly consolidate the current state-of-the-art technology regarding the role of autophagy in osteoclast function in both physiologic and pathologic conditions to have a more general view on this issue

The Effect of Educating the Use of Developmental Positions of Premature Infants on the Clinical Performance of Neonatal Intensive Care Unit Nurses

BACKGROUND AND OBJECTIVE: One of the early interventions in neurodevelopmental disorders in neonatal intensive care units is providing proper conditions for infants. Premature infants have lost their last three months of life in the uterus, and as a result, have not reached a collapsed status, which is a developmental position that indicates brain growth in the infant. Considering the importance of the neonatal position in developmental positions and achievement of better neural evolution, this study was conducted to implement educational intervention to improve the performance of nurses in order to properly implement the developmental positions of premature infants in neonatal intensive care unit. METHODS: This interventional study was carried out among 85 neonatal intensive care unit nurses in Shahid Akbar-Abadi and Ali Asghar Hospitals in Tehran in three stages. First, the nurses' performance was evaluated regarding the supportive developmental positions of the premature infants in the neonatal intensive care unit through a neonatal assessment tool (IPAT with a maximum score of 12 and a minimum score of 3). Then, nurses were educated by slides and face to face and the performance of nurses was evaluated and compared after the first week after training and two months after the training. FINDINGS: Demographic data showed that the education level of most nurses (98.8%) was bachelor's degree and most nurses (48.2%) were older than 30 years of age. The highest work experience of nurses (42.4%) was in the range of 5–10 years. In addition, the nurses' performance score regarding the supportive developmental position of premature infants in the pre-training stage (5.84±0.03), the first week after training (8.35±1.42) and two months after training (8.71±1.16) had a significant difference (p<0.001). CONCLUSION: Based on the results of this research, educating the use of developmental positions of premature infants has positive effects on the clinical performance of neonatal intensive care unit nurses

Dynamics of fully coupled rotators with unimodal and bimodal frequency distribution

We analyze the synchronization transition of a globally coupled network of N phase oscillators with inertia (rotators) whose natural frequencies are unimodally or bimodally distributed. In the unimodal case, the system exhibits a discontinuous hysteretic transition from an incoherent to a partially synchronized (PS) state. For sufficiently large inertia, the system reveals the coexistence of a PS state and of a standing wave (SW) solution. In the bimodal case, the hysteretic synchronization transition involves several states. Namely, the system becomes coherent passing through traveling waves (TWs), SWs and finally arriving to a PS regime. The transition to the PS state from the SW occurs always at the same coupling, independently of the system size, while its value increases linearly with the inertia. On the other hand the critical coupling required to observe TWs and SWs increases with N suggesting that in the thermodynamic limit the transition from incoherence to PS will occur without any intermediate states. Finally a linear stability analysis reveals that the system is hysteretic not only at the level of macroscopic indicators, but also microscopically as verified by measuring the maximal Lyapunov exponent.Comment: 22 pages, 11 figures, contribution for the book: Control of Self-Organizing Nonlinear Systems, Springer Series in Energetics, eds E. Schoell, S.H.L. Klapp, P. Hoeve

A Monte Carlo Simulation-Based Approach to Evaluate the Performance of Three Meteorological Drought Indices in Northwest of Iran

Although meteorological drought indices are considered as important tools for drought monitoring, they are embedded with different theoretical and experimental structures. Regarding the different geographic and climatic conditions around the world, the most meteorological drought indices have been commonly applied for drought monitoring in different parts of the world. Interestingly, it is observed that such indices in the published studies on drought monitoring have usually yielded inconsistent performance. On the other hand, most studies on drought monitoring as well as the performance of drought indices has been based on short-term historical data (less than 50 years). Therefore, this study aimed to analyze and compare the performance of three common indices of SPI, RAI and PNPI to predict long-term drought events using the Monte Carlo procedure and historical data. To do this end, the 50-year recorded or historical rainfall data across 11 synoptic stations in the Northwest of Iran were employed to generate 1000 synthetic data series so that the characteristics of long-term drought might be determined and the performance of those three indices might be analyzed and compared. The results indicated a very high comparative advantage of the SPI in terms of yielding a satisfactory and detailed analysis to determine the characteristics of long-term drought. Also, the RAI indicated significant deviations from normalized natural processes. However, these results could not reasonably and sufficiently predict long-term drought. Finally, the PNPI was determined as the most uncertain and spatial index (depending on average or coefficient of variation of rainfall data) in drought monitoring