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In recent years, advancements in brain science and neuroscience have significantly influenced the field of computer science, particularly in the domain of reinforcement learning (RL). Drawing insights from neurobiology and neuropsychology, researchers have leveraged these findings to develop novel mechanisms for understanding intelligent decision-making processes in the brain. Concurrently, the emergence of quantum computing has opened new frontiers in artificial intelligence, leading to the development of quantum machine learning (QML). This study introduces a novel model that integrates quantum spiking neural networks (QSNN) and quantum long short-term memory (QLSTM) architectures, inspired by the complex workings of the human brain. Specifically designed for reinforcement learning tasks in energy-efficient environments, our approach progresses through two distinct stages mirroring sensory and memory systems. In the initial stage, analogous to the brain's hypothalamus, low-level information is extracted to emulate sensory data processing patterns. Subsequently, resembling the hippocampus, this information is processed at a higher level, capturing and memorizing correlated patterns. We conducted a comparative analysis of our model against existing quantum models, including quantum neural networks (QNNs), QLSTM, QSNN and their classical counterparts, elucidating its unique contributions. Through empirical results, we demonstrated the effectiveness of utilizing quantum models inspired by the brain, which outperform the classical approaches and other quantum models in optimizing energy use case. Specifically, in terms of average, best and worst total reward, test reward, robustness, and learning curve. [ABSTRACT FROM AUTHOR]

Frontal ablation is responsible for a large fraction of the mass loss from tidewater glaciers. The main contributors to frontal ablation are iceberg calving and submarine melting, with calving often being the largest. However, submarine melting, in addition to its direct contribution to mass loss, also promotes calving through the changes induced in the stress field at the glacier terminus, so both processes should be jointly analysed. Among the factors influencing submarine melting, the formation of a buoyant plume due to the emergence of fresh subglacial water at the glacier grounding line plays a key role. In this study we used Elmer/Ice to develop a 3D glacier dynamics model including calving and subglacial hydrology coupled with a line plume model to calculate the calving front position at every time step. We applied this model to the Hansbreen–Hansbukta glacier–fjord system in southern Spitsbergen, Svalbard, where a large set of data are available for both the glacier and the fjord from September 2008 to March 2011. We found that our 3D model reproduced the expected seasonal cycle of advance–retreat. Besides, the modelled front positions were in good agreement with the observed front positions at the central part of the calving front, with longitudinal differences, on average, below 15 m for the period from December 2009 to March 2011. But there were regions of the front, especially the eastern margin, that presented major differences. [ABSTRACT FROM AUTHOR]

Background: Progression diets after bariatric surgery (BS) are restricted in calories and protein, and they may induce a worsening of body composition. The aim of this study was to evaluate the effect of a modified diet with an oral nutritional supplement that is hyperproteic and normocaloric over the body composition. Methods: A two-arm ambispective observational cohort study was designed. Forty-four patients who underwent sleeve gastrectomy were included in the study. Thirty patients received a progression diet with a normocaloric, hyperproteic oral nutritional supplement during the first two weeks after surgery (820 kcal, 65.5 g protein). They were compared with a historical cohort of 14 patients treated with a standard progression diet (220 kcal, 11.5 g protein). Anthropometric and body composition (using electrical bioimpedanciometry) data were analyzed before BS and 1 month after the surgery. Results: The mean age was 47.35(10.22) years; 75% were women, and the average presurgical body mass index (BMI) was 45.98(6.13) kg/m2, with no differences between both arms of intervention. One month after surgery, no differences in the percentage of excess weight loss (%PEWL) were observed between patients in the high-protein-diet group (HP) and low-protein-diet group (LP) (HP: 21.86 (12.60)%; LP: 18.10 (13.49)%; p = 0.38). A lower loss of appendicular skeletal muscle mass index was observed in the HP (HP: −5.70 (8.79)%; LP: −10.54 (6.29)%; p < 0.05) and fat-free mass index (HP: 3.86 (8.50)%; LP:−9.44 (5.75)%; p = 0.03), while a higher loss of fat mass was observed in the HP (HP: −14.22 (10.09)%; LP: −5.26 (11.08)%; p < 0.01). Conclusions: In patients undergoing gastric sleeve surgery, the addition of a normocaloric, hyperproteic formula managed to slow down the loss of muscle mass and increase the loss of fat mass with no differences on total weight loss. [ABSTRACT FROM AUTHOR]

The hydrography of the Arctic Ocean has experienced profound changes over the last 2 decades. The sea ice extent has declined by more than 10 % per decade, and its liquid freshwater content has increased mainly due to glaciers and sea ice melting. Further, new satellite retrievals of sea surface salinity (SSS) in the Arctic might contribute to better characterizing the freshwater changes in cold regions. Ocean salinity and freshwater content are intimately related such that an increase (decrease) in one entails a decrease (increase) in the other. In this work, we evaluate the freshwater content in the Beaufort Gyre using surface salinity measurements from the satellite radiometric mission Soil Moisture and Ocean Salinity (SMOS) and TOPAZ4b reanalysis salinity at depth, estimating the freshwater content from 2011 to 2019 and validating the results with in situ measurements. The results highlight the underestimation of the freshwater content using reanalysis data in the Beaufort Sea and a clear improvement in the freshwater content estimation when adding satellite sea surface salinity measurements in the mixed layer. The improvements are significant, with up to a 70 % reduction in bias in areas near the ice melting. Our research demonstrates how remotely sensed salinity can assist us in better monitoring the changes in the Arctic freshwater content and understanding key processes related to salinity variations that cause density differences with potential to influence the global circulation system that regulates Earth's climate. [ABSTRACT FROM AUTHOR]

Frontal ablation is responsible for a large fraction of the mass loss from tidewater glaciers. The main contributors to frontal ablation are iceberg calving and submarine melting, with calving being the largest. However, submarine melting, in addition to its direct contribution to mass loss, also promotes calving through the changes induced in the stress field at the glacier terminus, so both processes should be jointly analysed. Among the factors influencing submarine melting, the formation of a buoyant plume due to the emergence of fresh subglacial water at the glacier grounding line plays a key role. In this study we used Elmer/Ice to develop a 3D glacier dynamics model including calving and subglacial hydrology, coupled with a lineplume model to calculate the calving front position at every time-step. We applied this model to the Hansbreen-Hansbukta glacier-fjord system in Southern Spitsbergen, Svalbard, where a large set of data are available for both glacier and fjord, from September 2008 to March 2011. We found that our 3D model reproduced the expected seasonal cycle of advance-retreat. Besides, the modelled front positions were in good agreement with the observed front positions at the central part of the calving front, with longitudinal differences, on average, below 15 meters for the period from December 2009 to March 2011. But there were regions of the front presenting major differences, specially the eastern margin. [ABSTRACT FROM AUTHOR]

During the second half of the 20th century, the Antarctic Peninsula region has undergone a long and sustained warming period, followed by a shorter but also sustained cooling period, and then a very recent return to warming conditions. All of these have profoundly impacted the glaciers peripheral to the Antarctic Peninsula. This paper focuses on the analysis of the surface mass balance monitoring of such glaciers by the glaciological method, complemented by the analysis of mass-balance estimates by geodetic methods, as well as frontal ablation estimates. We aim to summarize the current knowledge and outline the main challenges faced by investigating the mass balance of such peripheral glaciers and their current contribution to sea-level rise. [ABSTRACT FROM AUTHOR]

In a context of scarcity, where it is estimated that the urban population will be 66% by the year 2050, the process of urbanization of poverty has become one of the most significant challenges of the 21st century. In Latin America, 113 million people live in selfproduced settlements and in Argentina, according to the latest update of the National Registry of LowIncome Neighborhoods, five million people live in the country’s 5,687 popular neighborhoods. This article aims to analyze to what extent do public policies contribute or not to promote socio-spatial justice, according to Nancy Fraser’s critical theory, in co-produced low-income neighborhoods in the Matanza Riachuelo hydrographic basin in the Autonomous City of Buenos Aires between the years 2016 and 2019. The results show that, in the majority of cases, families residing in these neighborhoods are the ones who have worked the hardest to promote socio-spatial justice. However, these efforts are not only unrecognized by the public administration, but also their representation in decision-making spaces has been hampered, and the redistributive practices and policies impeded. [ABSTRACT FROM AUTHOR]

62.8% of the Romani population in Spain lives in settlements that are segregated from the urban center or in peripheral neighborhoods, a sign of their historical persecution and discrimination. Anti-Romani sentiment has been territorialized by eliminating autonomy and means of self-production of space, with urban planning and housing policies being a key element in the materialization of their urban segregation, particularly during the Franco regime. Identifying the Romani as a surplus element in urban space led to their expulsion from self-produced housing, relocating them to peripheral social housing neighborhoods. Through the case studies, this article analyzes the Lo Campano and Los Mateos neighborhoods in Cartagena, Spain, the production of socio-spatial injustice against the Romani during Franco's regime, using Nancy Fraser's (1996) definition of social justice, and Giddens' (1994) structuration theory, as an analytical framework. The results obtained point to the role of urban planning and housing policies in the production of socio-spatial injustice, forming an exercise of urban and housing necropolitics against the Romani people. [ABSTRACT FROM AUTHOR]