Markovianization with approximate unitary designs

Memoryless processes are ubiquitous in nature, in contrast with the mathematics of open systems theory, which states that non-Markovian processes should be the norm. This discrepancy is usually addressed by subjectively making the environment forgetful. Here we prove that there are physical non-Markovian processes that with high probability look highly Markovian for all orders of correlations; we call this phenomenon Markovianization. Formally, we show that when a quantum process has dynamics given by an approximate unitary design, a large deviation bound on the size of non-Markovian memory is implied. We exemplify our result employing an efficient construction of an approximate unitary circuit design using two-qubit interactions only, showing how seemingly simple systems can speedily become forgetful. Conversely, since the process is closed, it should be possible to detect the underlying non-Markovian effects. However, for these processes, observing non-Markovian signatures would require highly entangling resources and hence be a difficult task.Comment: 6+9 pages, 5 figures. Published version, only presentation change

Almost Markovian processes from closed dynamics

It is common, when dealing with quantum processes involving a subsystem of a much larger composite closed system, to treat them as effectively memory-less (Markovian). While open systems theory tells us that non-Markovian processes should be the norm, the ubiquity of Markovian processes is undeniable. Here, without resorting to the Born-Markov assumption of weak coupling or making any approximations, we formally prove that processes are close to Markovian ones, when the subsystem is sufficiently small compared to the remainder of the composite, with a probability that tends to unity exponentially in the size of the latter. We also show that, for a fixed global system size, it may not be possible to neglect non-Markovian effects when the process is allowed to continue for long enough. However, detecting non-Markovianity for such processes would usually require non-trivial entangling resources. Our results have foundational importance, as they give birth to almost Markovian processes from composite closed dynamics, and to obtain them we introduce a new notion of equilibration that is far stronger than the conventional one and show that this stronger equilibration is attained.Comment: 9 pages, 13 pages of appendices, 5 figures, numerical example. Replaced with journal version and fixed hyperlink

Effect of the microstructure generated by repetitive corrugation and straightening (RCS) process on the mechanical properties and stress corrosion cracking of Al-7075 alloy

This study discussed the effect of the heterogeneous microstructure generated through the Repetitive Corrugation and Straightening (RCS) process on the mechanical and stress corrosion cracking behavior of the AA7075. As a result of the RCS process, significant grain refinement was obtained. The average grain size ranged from 126 to 59 µm, for the initial condition and 4 RCS passes, respectively. The yield strength and hardness increased 170% and 15% from the initial pass, remaining almost constant afterward. The evaluation of stress corrosion cracking showed a decrement in the number of cracks of 21.6% and 23.5% between the initial condition and fourth RCS passes. The cracking and pitting corrosion were the dominant mechanisms in the tested samples. The mechanical and corrosion results were also discussed in terms of the microstructural features.Peer ReviewedPostprint (published version

Las especies exóticas predominan en la flora leñosa urbana de Chile central

The expansion of cities promotes the replacement of local biotas with exotic species causing a decrease in global diversity.As urbanization continues to expand, efforts directed towards the conservation within urban landscapes could supportregional biodiversity conservation. The biogeographic region of central Chile displays a native flora of global importancebecause of its high endemism. Up to date, studies analysing the composition of the floras within the cities are scarce. Thepresent study aims at characterizing the compositional and distributional patterns of the ornamental flora of five cities ofcentral Chile (La Serena, Valparaíso, Santiago, Rancagua, and Talca). For this purpose, we sampled several streets andsquares recording all woody species. The species were then characterized by their biogeographical origin and incidence.It was recorded 302 species of which approx. 86% were exotic and 14% were native, a consistent pattern found in the fivecities studied; these results contrast with the European urban flora, where native species can usually overcome 50% of theplant species. Almost half of the exotic species had their origin in Asia (including Australasia, Temperate, and TropicalAsia), Europe, and North America. Consequently, the representation of the regional flora within the urban context is lowfor central Chile, with the native species registered, accounting for only 0.81% of the total species described for thecountry. Urban habitats could support regional biodiversity conservation, so a shift towards sustainable urban planningcould promote local biological conservation.La expansión de las ciudades promueve el reemplazo de biotas locales (nativas) por especies exóticas, lo que causa unadisminución en la diversidad. A medida que la urbanización continúa, los esfuerzos dirigidos a la conservación dentrode los paisajes urbanos podrían apoyar la conservación de la biodiversidad regional. La región biogeográfica de ChileCentral muestra una flora nativa de importancia mundial debido a su alto endemismo. No obstante, hasta la fecha haypocos estudios que analicen la composición de las floras dentro de las ciudades de esta región. El presente estudio analizala composición de la flora ornamental para cinco ciudades de Chile central: La Serena, Valparaíso, Santiago, Rancaguay Talca. Para ello realizamos un muestreo de calles y plazas de estas ciudades, registrando especies de plantas leñosas,distinguiendo su origen biogeográfico y su incidencia. Se registraron 302 especies de las cuales aprox. el 86% fueronespecies exóticas y el 14% nativas, patrón numéricamente consistente en las cinco ciudades estudiadas. Casi la mitad delas especies exóticas provienen de Asia (incluyendo Australasia y Asia tropical y templada), Norteamérica y Europa. Enconsecuencia, la representación de la flora regional dentro del contexto urbano es baja para el centro de Chile. Los habitatsurbanos podrían apoyar la conservación de la biodiversidad regional, por lo que un cambio hacia una planificación urbanasostenible podría promover la conservación biológica local

A systematic review of the biomarkers associated with cognition and mood state in bipolar disorder

Background Bipolar disorder (BD) is a severe psychiatric disorder characterized by changes in mood that alternate between (hypo) mania or depression and mixed states, often associated with functional impairment and cognitive dysfunction. But little is known about biomarkers that contribute to the development and sustainment of cognitive defcits. The aim of this study was to review the association between neurocognition and biomarkers across diferent mood states. Method Search databases were Web of Science, Scopus and PubMed. A systematic review was carried out fol‑ lowing the PRISMA guidelines. Risk of bias was assessed with the Newcastle–Ottawa Scale. Studies were selected that focused on the correlation between neuroimaging, physiological, genetic or peripheral biomarkers and cog‑ nition in at least two phases of BD: depression, (hypo)mania, euthymia or mixed. PROSPERO Registration No.: CRD42023410782. Results A total of 1824 references were screened, identifying 1023 published articles, of which 336 were considered eligible. Only 16 provided information on the association between biomarkers and cognition in the diferent afective states of BD. The included studies found: (i) Diferences in levels of total cholesterol and C reactive protein depending on mood state; (ii) There is no association found between cognition and peripheral biomarkers; (iii) Neuroimaging biomarkers highlighted hypoactivation of frontal areas as distinctive of acute state of BD; (iv) A deactivation failure has been reported in the ventromedial prefrontal cortex (vmPFC), potentially serving as a trait marker of BD. Conclusion Only a few recent articles have investigated biomarker-cognition associations in BD mood phases. Our fndings underline that there appear to be central regions involved in BD that are observed in all mood states. However, there appear to be underlying mechanisms of cognitive dysfunction that may vary across diferent mood states in BD. This review highlights the importance of standardizing the data and the assessment of cognition, as well as the need for biomarkers to help prevent acute symptomatic phases of the disease, and the associated functional and cognitive impairment

Mechanical, stress corrosion cracking and crystallographic study on flat components processed by two combined severe plastic deformation techniques

Although the current field of application of Al–alloy 7075 (AA7075) is vast, it is still limited due to some drawbacks, especially due to its susceptibility to stress corrosion cracking (SCC). This work aims to evaluate the microstructural, mechanical, and stress corrosion cracking (SCC) behaviors on an AA7075 in flat format deformed by a combination of repetitive corrugation and straightening (RCS) and accumulative roll bonding (ARB) techniques. Four different deformation routes were applied, namely: ARB (A), RCS (R), RCS + ARB (RA) and ARB + RCS (AR). As expected, the efficiency for grain refinement depends on the applied route, in terms of average grain size regarding the initial condition IC): AR > A > RA > R. All conditions resulted in unimodal and widened grain size distributions of micro-, submicro- and nano-metric dimensions. The study of crystallographic orientations showed that route R did not generate any new texture, whereas different preferred orientations were obtained for routes A, RA, and AR. The hardness and three-point bending tests showed an improvement of mechanical strength in the following order: AR > RA > A > R. The cracks per cm2 obtained in the corrosion study indicated that the best SCC resistance was R > A > AR > RA. Based on the above, the best combination of microstructural, mechanical, and SCC properties until one deformation pass was obtained by the single route of the ARB process.Peer ReviewedPostprint (published version

Trend, Associated Factors and Concordance of Obesity by Body Mass Index, Waist Circumference and Waist-Height Ratio in Adolescents. An Analysis of a 4-Year National Survey

Introduction: Regarding diagnosis, identifying reliable anthropometric measures to detect adolescent obesity is fundamental. However, in this age group has different definitions, either according to the body mass index (BMI), the waist circunference (WC) and the waist-height ratio (WHtR), making the measurement of this inaccurate. Objective: This study analyzed the prevalence, trends, and factors associated with obesity in Peruvian adolescents using data from the Demographic and Health Survey (ENDES) for 2019-2022. Methods: A secondary data analysis was conducted on 14,330 adolescents aged 15 to 19. The response variable was obesity, defined in three different ways. General obesity was assessed using the BMI was ≥ 2 standard deviations. 2) Abdominal obesity was defined through WC, with cutoff points ≥ 80.5 cm in men and ≥ 81 cm in women. 3) The relevant indicator for obesity was the WHtR, with a cutoff point ≥ 0.5. The associated factors to be evaluated were sex, age, natural region, marital status, education level, wealth, area of residence, alcohol consumption, and physical disability. Results: The study found that based on BMI, WC, and WHtR respectively, approximately 12.80%, 29.72%, and 24.27% of participants were considered obese. Significant associations were found between obesity and variables such as gender, natural region, marital status, wealth index, area of residence, education level, alcohol consumption, and physical disability. Conclusion: This research uncovered an alarmingly prevalence occurrence of obesity among adolescents in Peru with fluctuating patterns over time, emphasizing the need to tackle the interconnected issues contributing to this health concern. These findings can help inform and guide obesity prevention and control strategies in this population

Early life metal dysregulation in amyotrophic lateral sclerosis

ObjectiveDeficiencies and excess of essential elements and toxic metals are implicated in amyotrophic lateral sclerosis (ALS), but the age when metal dysregulation appears remains unknown. This study aims to determine whether metal uptake is dysregulated during childhood in individuals eventually diagnosed with ALS.MethodsLaser ablation- inductively coupled plasma- mass spectrometry was used to obtain time series data of metal uptake using biomarkers in teeth from autopsies or dental extractions of ALS (n = 36) and control (n = 31) participants. Covariate data included sex, smoking, occupational exposures, and ALS family history. Case- control differences were identified in temporal profiles of metal uptake for individual metals using distributed lag models. Weighted quantile sum (WQS) regression was used for metals mixture analyses. Similar analyses were performed on an ALS mouse model to further verify the relevance of dysregulation of metals in ALS.ResultsMetal levels were higher in cases than in controls: 1.49 times for chromium (1.11- 1.82; at 15 years), 1.82 times for manganese (1.34- 2.46; at birth), 1.65 times for nickel (1.22- 2.01; at 8 years), 2.46 times for tin (1.65- 3.30; at 2 years), and 2.46 times for zinc (1.49- 3.67; at 6 years). Co- exposure to 11 elements indicated that childhood metal dysregulation was associated with ALS. The mixture contribution of metals to disease outcome was likewise apparent in tooth biomarkers of an ALS mouse model, and differences in metal distribution were evident in ALS mouse brains compared to brains from littermate controls.InterpretationOverall, our study reveals direct evidence that altered metal uptake during specific early life time windows is associated with adult- onset ALS.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155978/1/acn351006_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155978/2/acn351006.pd

SUMOylation of the mitochondrial fission protein Drpl occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle

Dynamin‐related protein (Drp) 1 is a key regulator of mitochondrial fission and is composed of GTP‐binding, Middle, insert B, and C‐terminal GTPase effector (GED) domains. Drpl associates with mitochondrial fission sites and promotes membrane constriction through its intrinsic GTPase activity. The mechanisms that regulate Drpl activity remain poorly understood but are likely to involve reversible post‐translational modifications, such as conjugation of small ubiquitin‐like modifier (SUMO) proteins. Through a detailed analysis, we find that Drpl interacts with the SUMO‐conjugating enzyme Ubc9 via multiple regions and demonstrate that Drpl is a direct target of SUMO modification by all three SUMO isoforms. While Drpl does not harbor consensus SUMOylation sequences, our analysis identified2 clusters of lysine residues within the B domain that serve as noncanonical conjugation sites. Although initial analysis indicates that mitochondrial recruitment of ectopically expressed Drpl in response to staurosporine is unaffected by loss of SUMOylation, we find that Drpl SUMOylation is enhanced in the context of the K38A mutation. This dominant‐negative mutant, which is deficient in GTP binding and hydrolysis, does not associate with mitochondria and prevents normal mitochondrial fission. This finding suggests that SUMOylation of Drpl is linked to its activity cycle and is influenced by Drpl localization.—Figueroa‐Romero, C., Iniguez‐Lluhi, J. A., Stadler, J., Chang, C.‐R., Arnoult, D., Keller, P. J., Hong, Y., Blackstone, C., Feldman, E. L. SUMOylation of the mitochondrial fission protein Drpl occurs at multiple nonconsensus sites within the B domain and is linked to its activity cycle. FASEB J. 23, 3917–3927 (2009). www.fasebj.orgPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154272/1/fsb2fj09136630.pd