On the complexity of quantum link prediction in complex networks

Link prediction methods use patterns in known network data to infer which connections may be missing. Previous work has shown that continuous-time quantum walks can be used to represent path-based link prediction, which we further study here to develop a more optimized quantum algorithm. Using a sampling framework for link prediction, we analyze the query access to the input network required to produce a certain number of prediction samples. Considering both well-known classical path-based algorithms using powers of the adjacency matrix as well as our proposed quantum algorithm for path-based link prediction, we argue that there is a polynomial quantum advantage on the dependence on N, the number of nodes in the network. We further argue that the complexity of our algorithm, although sub-linear in N, is limited by the complexity of performing a quantum simulation of the network's adjacency matrix, which may prove to be an important problem in the development of quantum algorithms for network science in general.

Political quarrel overshadows vaccination advocacy: How the vaccine debate on Brazilian Twitter was framed by anti-vaxxers during Bolsonaro administration

Despite Brazil's tradition of successful mass immunization programs, the country has been experiencing alarming declines in vaccination coverage, especially among children. That is aggravated by the growth of anti-vaccine movements and the spread of health misinformation in social media in the last decade, which have worsened during the COVID-19 outbreak. Several reports link populism and far-right politicians to anti-vaccination support worldwide, which was also the case in Brazil during president Jair Bolsonaro's administration. This project aimed to identify the circulating pro and anti-vaccine narratives in Portuguese on Twitter, during a crucial decision-making period regarding childhood vaccination in Brazil, from December 9, 2021, until February 9, 2022. From the over one million tweets and four million retweets collected, we identified two well-defined groups, one in favor and another against vaccination. Within the sample, we selected 1500 influencer tweets with the highest impact (>500 retweets) and conducted content analysis. Although the pro-vaccine influencers were more retweeted than anti-vaxxer ones, we observed that anti-vaccine movements were more succesful in framing discussions on Twitter. The subject of COVID-19 was the target of political polarization embedded in populist, anti-science and anti-traditional media discourses promoted by anti-vaxxers. As a counterpart, the pro-vaccine influencers reacted inarticulately, focusing on criticizing the anti-vaccination actors, attitudes, and policies instead of promoting vaccines. Based on reults, we claim that a well-coordinated network of health communicators from science centers and health institutions, in partnership with properly briefed social media influencers and fact-checking sources, would more efectively pre-tempt the public about vaccine misinformation.

Operationalizing Integrated Water Resource Management in Latin America: Insights from Application of the Freshwater Health Index

Water crises in Latin America are more a consequence of poor management than resource scarcity. Addressing water management issues through better coordination, identification of problems and solutions, and agreement on common objectives to operationalize integrated water resources management (IWRM) could greatly improve water governance in the region. Composite indices have great potential to help overcome capacity and information challenges while supporting better IWRM. We applied one such index, the Freshwater Health Index (FHI) in three river basins in Latin America (Alto Mayo, Perú; Bogotá, Colombia; and Guandu, Brazil) to assess freshwater ecosystem vitality, ecosystem services, and the water governance system in place. The approach included convening management agencies, water utilities, planning authorities, local NGOs and industries, community groups and researchers to co-implement the FHI. The results provide detailed information on the ecological integrity of each basin and the sustainability of the ecosystem services being provided. All three basins show very low scores for governance and stakeholder engagement, thus improving both in the region should be a priority. The results also shed light on how the FHI framework can help inform decision-making to improve IWRM implementation by facilitating stakeholder engagement while contributing to coordination, identification of problems and solutions as well as agreement on common objectives. Because implementation of IWRM is part of the solution for the United Nations Sustainable Development Goal (SDG) 6.5 ("By 2030, implement IWRM at all levels, including through transboundary cooperation as appropriate"), our case studies can serve as examples to other Latin American countries to achieve SDG 6.5.

Seasonal sensitivity and psychiatric morbidity: study about seasonal affective disorder

BACKGROUND

Seasonal Affective Disorder is a recurrent depressive disorder which usually begins in the fall/winter and enters into remission in the spring/summer, although in some cases may occur in the summer with remission in the autumn-winter. In this study the authors evaluated the association between seasonal changes in mood and behavior with psychiatric disturbance.

METHOD

Descriptive, cross-sectional study. Participants, students attending higher education and vocational courses (N = 324), were evaluated with the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Screening Scale for Mental Health (ER80).

RESULTS

Among the respondents, 12.7% showed seasonal affective disorder (SAD), 29.0% showed subsyndromal seasonal affective disorder (s-SAD) and 58.3% did not show significant seasonal affective symptomatology. As for psychiatric morbidity, 36.6% of subjects with SAD and 13.8% of those with s-SAD were considered "psychiatric cases" whereas for subjects without SAD this value was only 3.2%.

CONCLUSIONS

There is a statistically significant association between psychiatric morbidity and seasonal affective disorder. This association corroborates the importance of the Seasonal Pattern Assessment Questionnaire in screening for seasonal fluctuations in mood and behavior related disorders, and the clinical need for recognition of these conditions, particularly associated suffering and disabilities.

The uncertain future of protected lands and waters

Protected areas are intended to safeguard biodiversity in perpetuity, yet evidence suggests that widespread legal changes undermine protected area durability and efficacy. We documented these legal changes—protected area downgrading, downsizing, and degazettement (PADDD) events—in the United States and Amazonian countries and compiled available data globally. Governments of the United States and Amazonian countries enacted 269 and 440 PADDD events, respectively. Between 1892 and 2018, 73 countries enacted 3749 PADDD events, removing 519,857 square kilometers from protection and tempering regulations in an additional 1,659,972 square kilometers; 78% of events were enacted since 2000. Most PADDD events (62%) are associated with industrial-scale resource extraction and development, suggesting that PADDD may compromise biodiversity conservation objectives. Strategic policy responses are needed to address PADDD and sustain effective protected areas.

Enhanced NMR relaxation of fluids confined to porous media: A proposed theory and experimental tests

We propose a theory to account for the NMR relaxation of water protons in situations in which the fluid is confined to porous structures exhibiting a scarce distribution of paramagnetic centers on their surface. Though much of what is stated and assumed concerns the response of water, the model has sufficiently general features to be able to explain proton relaxation of other polar fluids under similar conditions. One of the main results of the paper is to show that the local anisotropy introduced by the dominant dipolar coupling in the relaxation rates of active surface elements induces a measurable dependence on sample orientation in the overall relaxation rates of the saturating fluid provided its confining structure is not statistically isotropic. Measurements of T_{1} proton relaxation on water saturating microcapillary tubes are performed to reveal the effect.

Questionário de Avaliação do Perfil Sazonal — Características psicométricas da versão portuguesa do Seasonal Pattern Assessment Questionnaire (SPAQ)

Introdução/Objetivo: Alterações sazonais do humor e do comportamento caracterizadas por estados depressivos no outono/inverno e remissão na primavera/verão são condições muito frequentes. Para identificar a sensibilidade dos sujeitos às alterações sazonais o Seasonal Pattern Assessment Questionnaire (SPAQ) é provavelmente o instrumento de autoavaliação mais utilizado. O presente estudo avalia as propriedades psicométricas da versão portuguesa do SPAQ.Material e métodos: A amostra foi constituída por estudantes universitários e de cursos profissionais (137 homens, 187 mulheres; média das idades = 27.7 ± 9.8). A análise do SPAQ centrou‑se nos itens que constituem a Pontuação Global de Sazonalidade – PGS (Global Seasonality Score – GSS) e na categorização dos sujeitos em subtipos: sem perturbação afetiva sazonal (sem PAS); subsíndrome da perturbação afetiva sazonal (S‑PAS); perturbação afetiva sazonal (PAS).Resultados: A média da Pontuação Global de Sazonalidade foi de 9.1 ± 4.3, não se verificando diferenças significativas entre homens e mulheres. A consistência interna dos itens que constituem a Pontuação Global de Sazonalidade foi 0.804 (α de Cronbach) e a correlação média inter‑itens de r = 0.406. Com base nas respostas ao questionário, 29.0% correspondiam a subsíndrome afetiva sazonal e 12.7% a perturbação afetiva sazonal. Independentemente da gravidade, 30.6% dos inquiridos consideravam as alterações sazonais do humor e do comportamento como problema.Conclusão: O SPAQ revela ser um instrumento de autoavaliação com boas propriedades psicométricas, fácil de aplicar. Considerando a amostra estudada os resultados sugerem que as variações sazonais do humor e do comportamento são muito frequentes. O facto de se encontrarem valores superiores ao de outros estudos efetuados em populações não clínicas evidencia a necessidade de se avaliar a especificidade do questionário e de se realizarem estudos em amostras representativas da população.

Post-stroke acute elation shortly followed by pathologic jealousy - is there a common anatomic substrate?

Both mania and psychotic symptoms are well known to result from vascular brain injury, but their pathophysiology remains largely unknown.

A 69-year-old man with diabetes and hypertension was seen for sudden behaviour disturbance: euphoric, talkative and uninhibited, he continuously shouted he trusted in Medicine, called the doctor the “King of Medicine”, and repeatedly said “I love doctors, I love nurses, I love Hospitals”. He was overcompliant during neurologic exploration, clearly amused with it. Left sensitive hemi-inattention and left homonymous hemianópsia could also be found. MRI showed an acute right temporo-parieto-insular cortical infarction. The following day he was euthymic and embarrassed for what happened. When visited that afternoon by his wife, she noticed he was strangely suspicious, continuously surveilling all her moves. He progressively worsened, believing she was having affairs with several men. This delusion persisted for the following months, even on risperidone 1 mg/day, culminating in Christmas Eve, when the patient shocked his family saying that his wife was having an affair with one of their sons. At this time, risperidone was discontinued and replaced by quetiapine 200 mg/day, resulting in rapid fading of all symptoms.

Both post-stroke mania and psychotic symptoms have been consistently associated with right hemisphere damage, but, to our knowledge, were not previously reported after the same injury. We believe our patient provides evidence that the same anatomic dysfunction, in this case a temporoparietal infarct, can cause both psychiatric phenomena.