First measurement of decimeter-sized rocky material in the Oort cloud

The Oort cloud is thought to be a reservoir of icy planetesimals and a source of long-period comets (LPCs) implanted from the outer Solar System during the time of giant planet formation. The presence of rocky ice-free bodies is much harder to explain. The rocky fraction in the Oort cloud is a key diagnostic of Solar System formation models as this ratio can distinguish between "massive" and "depleted" proto-asteroid belt scenarios and thus disentangle competing planet formation models. Objects of asteroidal appearance have been telescopically observed on LPC orbits, but from reflectance spectra alone it is uncertain whether they are asteroids or extinct comets. Here we report a first direct observation of a decimeter-sized rocky meteoroid on a retrograde LPC orbit (e ≈ 1.0, i = 121°). The ~2 kg object entered the atmosphere at 62 km/s. The associated fireball terminated at 46.5 km, 40 km deeper than cometary objects of similar mass and speed. During its flight, it experienced dynamic pressures of several MPa, comparable to meteorite-dropping fireballs. In contrast, cometary material measured by Rosetta have compressive strengths of ~1 kPa. The earliest fragmentation of this fireball occurred at >100 kPa, indicating it had a minimum global strength well in excess of cometary. A numerical ablation model produces bulk density and ablation properties consistent with asteroidal meteoroids. We estimate the flux of rocky objects impacting Earth from the Oort cloud to be ~0.7 × 106 km2 per year to a mass limit of 10 g. This is ~6% of the total flux of fireballs on LPC-orbits to these masses. Our results suggests there is a high fraction of asteroidal material in the Oort cloud at small sizes and gives support to migration-based dynamical models of the formation of the Solar System which predict that significant rocky material is implanted in the Oort cloud, a result not explained by traditional Solar System formation models.

Network Analysis of Depressive Symptoms Among Residents of Wuhan in the Later Stage of the COVID-19 Pandemic

Background: Depression has been a common mental health problem during the COVID-19 epidemic. From a network perspective, depression can be conceptualized as the result of mutual interactions among individual symptoms, an approach that may elucidate the structure and mechanisms underlying this disorder. This study aimed to examine the structure of depression among residents in Wuhan, the epicenter of the COVID-19 outbreak in China, in the later stage of the COVID-19 pandemic.Methods: A total of 2,515 participants were recruited from the community via snowball sampling. The Patient Health Questionnaire was used to assess self-reported depressive symptoms with the QuestionnaireStar program. The network structure and relevant centrality indices of depression were examined in this sample.Results: Network analysis revealed Fatigue, Sad mood, Guilt and Motor disturbances as the most central symptoms, while Suicide and Sleep problems had the lowest centrality. No significant differences were found between women and men regarding network structure (maximum difference = 0.11, p = 0.44) and global strength (global strength difference = 0.04; female vs. male: 3.78 vs. 3.83, p = 0.51), a finding that suggests there are no gender differences in the structure or centrality of depressive symptoms.Limitations: Due to the cross-sectional study design, causal relationships between these depressive symptoms or dynamic changes in networks over time could not be established.Conclusions: Fatigue, Sad mood, Guilt, and Motor disturbances should be prioritized as targets in interventions and prevention efforts to reduce depression among residents in Wuhan, in the later stage of the COVID-19 pandemic.

On the edge of criticality: strength-dependent perturbation unveils delicate balance between fluctuation and oscillation in brain dynamics

Going beyond previous research, we use strength-dependent perturbation to obtain a deeper understanding of the mechanisms underlying the emergence of large-scale brain activity. Despite decades of research, we still have a shallow understanding of the role and generating mechanisms of the ubiquitous fluctuations and oscillations found in recordings of brain dynamics. Here, we used global strength-dependent perturbation to give a causal mechanistic description of human brain function providing a delicate balance between fluctuation and oscillation on the edge of criticality. After application of precise local strength-dependent perturbations and measuring the well-known perturbative complexity index, we demonstrated that the overall balance is shifted towards a fluctuating regime which is superior in terms of enhancing different functional networks compared to the oscillatory regime. This framework can generate specific, testable empirical predictions to be tested in human stimulation studies with strength-dependent rather than constant perturbation. Overall, our novel strength-dependent perturbation framework demonstrates that the human brain is poised on the edge of criticality, between fluctuations to oscillations, allowing for maximal flexibility.

A detailed analysis of long-term outcomes following reconstruction for congenital thumb hypoplasia

This retrospective study analyses long-term outcomes of reconstruction for congenital thumb hypoplasia Grades 2 and 3 A. In 22 thumbs (mean follow-up 9 years), instability of the metacarpophalangeal joint was found in 20 thumbs regardless of the method of reconstruction, double breasting of local tissue with or without adductor pollicis advancement or use of a slip of flexor digitorum superficialis to supplement local tissue. There was a trend towards a greater global strength, higher Kapandji score and better subjective function score when the abductor digiti minimi was used as an opposition transfer as compared with the flexor digitorum superficialis. Results for motion and subjective parameters were consistent with comparable studies though these comparisons are compromised by different methods of classification and assessment. Consistent application of an expanded Blauth grading system and a formal hypoplastic thumb score will improve the ability to compare pre- and postoperative status, different techniques and results from different centres. Level of evidence: IV

Network analysis of depressive symptoms in Hong Kong residents during the COVID-19 pandemic

In network theory depression is conceptualized as a complex network of individual symptoms that influence each other, and central symptoms in the network have the greatest impact on other symptoms. Clinical features of depression are largely determined by sociocultural context. No previous study examined the network structure of depressive symptoms in Hong Kong residents. The aim of this study was to characterize the depressive symptom network structure in a community adult sample in Hong Kong during the COVID-19 pandemic. A total of 11,072 participants were recruited between 24 March and 20 April 2020. Depressive symptoms were measured using the Patient Health Questionnaire-9. The network structure of depressive symptoms was characterized, and indices of “strength”, “betweenness”, and “closeness” were used to identify symptoms central to the network. Network stability was examined using a case-dropping bootstrap procedure. Guilt, Sad Mood, and Energy symptoms had the highest centrality values. In contrast, Concentration, Suicide, and Sleep had lower centrality values. There were no significant differences in network global strength (p = 0.259), distribution of edge weights (p = 0.73) and individual edge weights (all p values > 0.05 after Holm–Bonferroni corrections) between males and females. Guilt, Sad Mood, and Energy symptoms were central in the depressive symptom network. These central symptoms may be targets for focused treatments and future psychological and neurobiological research to gain novel insight into depression.

Network Replicability & Generalizability: Exploring the Effects of Sampling Variability, Scale Variability, and Node Reliability

Work surrounding the replicability and generalizability of network models has increased in recent years, prompting debate as to whether network properties can be expected to be consistent across samples. To date, certain methodological practices may have contributed to observed inconsistencies, including the common use of single-item indicators to estimate nodes, and use of non-identical measurement tools. The current study used a resampling approach to systematically disentangle the effects of sampling variability from scale variability when assessing network replicability. Additionally, we explored the extent to which consistencies in network characteristics were improved when precision in node estimation was increased. Overall, scale variability produced less stability in network properties than sampling variability, however under more optimal measurement conditions (i.e. larger sample, greater node precision), discrepancies were markedly reduced. Findings also importantly underscored the value of improving node reliability: Use of multi-item indicators led to denser networks, higher network sensitivity, greater estimates of global strength, and greater levels of consistency in network properties (e.g., edge weights, centrality scores). Taken together, variability in network properties across samples may be less indicative of a lack of replicability, but may arise from poor measurement precision, and/or may reflect properties of the underlying true network model or scale-specific properties. All data and syntax are openly available online (https://osf.io/m37q2/).

God's Marshall Plan

God’s Marshall Plan explores the origins of Christian nationalism and Christian globalism—two competing theologies of global engagement—in the American Protestant encounter with twentieth-century Europe. It recovers the story of the American Protestants who crossed the Atlantic in an era of world war, tracked the rise of totalitarian dictators, mobilized against the Axis powers, and began to identify Europe as a continent in need of saving. In response, they launched far-reaching missions to spread their faith and democracy across the Atlantic. As they joined army platoons in occupying Germany, they singled out the defeated nation as the prime European territory for a new American-led, Christian and democratic world order that could thwart any totalitarian threat. Throughout these efforts, however, American Protestants realized they had come to dramatically different conclusions about how to rebuild Europe out of the ruins of war. Their diverging visions ultimately sparked a spiritual struggle for the continent and leadership of the postwar world. All the while, European Protestants began to sharply protest America’s spiritual advance. Faced by this challenge, a growing number of ecumenical Protestants rethought their efforts to build God’s kingdom through America’s global strength. Forsaking their wartime nationalism, they championed a new theology of global peace, reconciliation, and justice. A fresh wave of Protestant cold warriors surged forward, however, to retake their nation and promote a theology of liberty and anti-communism across the Atlantic. The spiritual struggle for Europe thus left American Protestants deeply divided and at odds over their global mission. It ultimately forged competing visions of global engagement that transformed the United States, diplomacy, and politics in the Cold War and beyond.

Network structure of ICD-11 adjustment disorder: a cross-cultural comparison of three African countries

Background Adjustment disorder is one of the most widespread mental disorders worldwide. In ICD-11, adjustment disorder is characterised by two main symptom clusters: preoccupation with the stressor and failure to adapt. A network analytic approach has been applied to most ICD-11 stress-related disorders. However, no study to date has explored the relationship between symptoms of adjustment disorder using network analysis. Aims We aimed to explore the network structure of adjustment disorder symptoms and whether its structure replicates across questionnaire versions and samples. Method A network analysis was conducted on adjustment disorder symptoms as assessed by the Adjustment Disorder–New Module (ADNM-8) and an ultra-brief version (ADNM-4) using data from 2524 participants in Nigeria (n = 1006), Kenya (n = 1018) and Ghana (n = 500). Results There were extensive connections between items across all samples in both ADNM versions. Results highlight that preoccupation symptoms seem to be more prominent in terms of edges strengths (i.e. connections) and had the highest centrality in all networks across samples and ADNM versions. Comparisons of network structure invariance revealed one difference between Nigeria and Ghana in both ADNM versions. Importantly, the ADNM-8 global strength was similar in all networks whereas in the ADNM-4 Kenya had a higher global strength score compared with Nigeria Conclusions Results provide evidence of the coherence of adjustment disorder in ICD-11 as assessed by the ADNM questionnaire. The prominence of preoccupation symptoms in adjustment disorder highlights a possible therapeutic target to alleviate distress. There is a need to further replicate the network structure of adjustment disorder in non-African samples.

Design finite element method based models of floating dry docks strength

The features of global strength modelling of floating dry docks using finite element method are considered. Comparative analysis of two- and three-dimensional models was performed considering the interaction of the floating dry dock and the ship. To solve the problem of reducing the complexity of creating and the size of the finite element model, it is proposed to use the elements of a volumetric orthotropic body to model the main transverse beams of the pontoon. Hydrostatic elastic base of floating dry dock is represented as spring elements. The model of the dock support device includes spring and gap elements. The vessel is considered in the equivalent beam model. Results were obtained on such effects as redistribution of buoyant force due to deformation of the dock, incomplete inclusion of the towers in the general longitudinal bending of the dock, the effect of ship stiffness not only on the longitudinal, but also on the transverse bending of the dock.

Exer-Gaming reduces fall risk and improves mobility after stroke

Objective: Major goal concealed behind conducting current study was to evaluate the effect of balance training via virtual reality in patients with chronic stroke having history of reduced global strength, reduced anticipatory balance and having history of fall. Methodology: A randomized control trial in which 30 chronic stroke survivors were recruited via purposive sampling technique was conducted. Sealed envelope method was used to randomly allocate patients into two groups that were Exer-gaming group (EGG) (n=15) and traditional training (TBT) group (n=15). Those patients having age above 50 were included using Modified Rankin Scale (MRS). Patients having cognitive deficits, severe contractures, unable to perform task, severe orthopedic condition of joint or those having fracture were not included in the study. The tools used to collect data included Berg Balance Scale (BBS), Timed Up & Go Test (TUG). The data was analyzed before starting the intervention and after every Continuous...