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van der Waals (vdW) magnets are receiving ever-growing attention nowadays due to their significance in both fundamental research on low-dimensional magnetism and potential applications in spintronic devices. The high crystalline quality of vdW magnets is the key to maintaining intrinsic magnetic and electronic properties, especially when exfoliated down to the two-dimensional limit. Here, ultrahigh-quality air-stable vdW CrSBr crystals are synthesized using the direct solid-vapor synthesis method. The high single crystallinity and spatial homogeneity have been thoroughly evidenced at length scales from submm to atomic resolution by X-ray diffraction, second harmonic generation, and scanning transmission electron microscopy. More importantly, specific heat measurements of ultrahigh-quality CrSBr crystals show three thermodynamic anomalies at 185, 156, and 132 K, revealing a stage-by-stage development of the magnetic order upon cooling, which is also corroborated with the magnetization and transport results. Our ultrahigh-quality CrSBr can further be exfoliated down to monolayers and bilayers easily, providing the building blocks of heterostructures for spintronic and magneto-optoelectronic applications.

Despite advances in infection prevention and control and breakthroughs in vaccination development, challenges remain for long-term care facilities (LTCFs) as they face a likely future of emerging infectious diseases. To ensure the safety of LTCF residents from the current and future pandemics, we identify lessons learned from the coronavirus disease 2019 (COVID-19) experience for improving future prevention and response efforts.In addition to high disease susceptibility among LTCF residents, LTCF vulnerabilities include a lack of pandemic preparedness, a lack of surge capacity in human, material and testing resources, and poorly designed buildings. External sources of vulnerability include staff working in multiple LTCFs and high COVID-19 rates in surrounding communities. Other challenges include poor cooperation between LTCFs and the other components of health systems, inadequately enforced regulations, and the sometimes contradictory interests for-profit LTCFs face between protecting their residents and turning a profit.These challenges can be addressed in the post-COVID-19 period through systemic reforms. Governments should establish comprehensive health networks that normalize mechanisms for prediction/preparedness and response/recovery from disruptive events including pandemics. In addition, governments should facilitate cooperation among public and private sector health systems and institutions while utilizing advanced digital communication technologies. These steps will greatly reduce the threat to LTCFs posed by emerging infectious diseases in future.

Measuring the three-dimensional (3D) distribution of chemistry in nanoscale matter is a longstanding challenge for metrological science. The inelastic scattering events required for 3D chemical imaging are too rare, requiring high beam exposure that destroys the specimen before an experiment completes. Even larger doses are required to achieve high resolution. Thus, chemical mapping in 3D has been unachievable except at lower resolution with the most radiation-hard materials. Here, high-resolution 3D chemical imaging is achieved near or below one nanometer resolution in a Au-Fe3O4 metamaterial, Co3O4 - Mn3O4 core-shell nanocrystals, and ZnS-Cu0.64S0.36 nanomaterial using fused multi-modal electron tomography. Multi-modal data fusion enables high-resolution chemical tomography often with 99% less dose by linking information encoded within both elastic (HAADF) and inelastic (EDX / EELS) signals. Now sub-nanometer 3D resolution of chemistry is measurable for a broad class of geometrically and compositionally complex materials.

Nanopore Sensitivity/Specificity details

All supplementary data except table S3A and S3B

Purpose:Pediatric high-grade glioma (pHGG) diagnosis portends poor prognosis and therapeutic monitoring remains difficult. Tumors release cell-free tumor DNA (cf-tDNA) into cerebrospinal fluid (CSF), allowing for potential detection of tumor-associated mutations by CSF sampling. We hypothesized that direct, electronic analysis of cf-tDNA with a handheld platform (Oxford Nanopore MinION) could quantify patient-specific CSF cf-tDNA variant allele fraction (VAF) with improved speed and limit of detection compared with established methods.Experimental Design:We performed ultra-short fragment (100–200 bp) PCR amplification of cf-tDNA for clinically actionable alterations in CSF and tumor samples from patients with pHGG (n = 12) alongside nontumor CSF (n = 6). PCR products underwent rapid amplicon-based sequencing by Oxford Nanopore Technology (Nanopore) with quantification of VAF. Additional comparison to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) was performed.Results:Nanopore demonstrated 85% sensitivity and 100% specificity in CSF samples (n = 127 replicates) with 0.1 femtomole DNA limit of detection and 12-hour results, all of which compared favorably with NGS. Multiplexed analysis provided concurrent analysis of H3.3A (H3F3A) and H3C2 (HIST1H3B) mutations in a nonbiopsied patient and results were confirmed by ddPCR. Serial CSF cf-tDNA sequencing by Nanopore demonstrated correlation of radiological response on a clinical trial, with one patient showing dramatic multi-gene molecular response that predicted long-term clinical response.Conclusions:Nanopore sequencing of ultra-short pHGG CSF cf-tDNA fragments is feasible, efficient, and sensitive with low-input samples thus overcoming many of the barriers restricting wider use of CSF cf-tDNA diagnosis and monitoring in this patient population.

Background Pulmonary embolism (PE) in the pediatric population is uncommon, and due to a silent presentation often unrecognized entity that remains one of the most challenging medical conditions in the emergency department (ED). Risk factors for PE in children include nephrotic syndrome, immobility, obesity, congenital heart disease, and malignancy. In patients with PE, thromboembolism has been reported to occur at unusual venous sites including the veins within the central nervous system and abdomen. Although penile pain is a rare presenting symptom in the ED, in patients with hypercoagulability, it can herald a life threating event such as PE prompting further evaluation. Case presentation A 15-year-old male with a history of B-cell acute lymphoblastic leukemia who presented to the ED with an 18-hour history of penile pain. In the ED, the patient was in acute distress and rated his pain as 9/10. Initial vital signs were within normal limits, except mild tachypnea. On physical examination, his penile shaft was erythematous, indurated, and tender to palpation. He received fentanyl and morphine for pain. A complete blood cell count revealed pancytopenia with a platelet count of 73 x 109/L (139–320 x 109/L). A work-up for sexually transmitted diseases, urolithiasis, urinary tract infection, deep venous thrombosis (DVT), and priapism was negative. Approximately two hours after morphine administration, his saturations started dropping to mid-70’s. A computed tomography pulmonary angiogram (CTPA) revealed bilateral segmental acute pulmonary embolism involving multiple segmental right and left lower lobe pulmonary arteries. Penile pain and hypoxia have resolved with heparin. Conclusions PE is easily missed diagnosis among children who present to the ED and can be potentially fatal. A high index of suspicion is required in asymptomatic and oligo-symptomatic children with prothrombotic risk factors who develop thromboembolism-related symptoms at unusual sites as well as hypoxia in the ED setting.

The psychological impact of a traumatic event includes potentially both negative (e.g., PTSD, depression, and anxiety) as well as positive (e.g., post-traumatic growth) outcomes. The construct of self-compassion—the capacity to be compassionate towards oneself—has been associated with various psychological benefits following disasters, however, the association between self-compassion and PTG have not yet been examined in natural disaster settings. This study aimed to examine the relationship between these constructs, with self-compassion as a potential mediator in this relationship. Three hundred and nine undergraduate students affected by the impact of Hurricane Harvey were recruited. Statistical analyses revealed a significant mediation effect, with PTSD symptoms being both directly and indirectly (via self-compassion) associated with PTG. The capacity to grow from traumatic experiences is mediated by one’s disposition to be compassionate towards oneself, serving as a resilience factor to provide individuals with the cognitive and emotional resources to grow after trauma. These findings have significant implications in both clinical and research contexts, including the use of self-compassion interventions to protect against PTSD and other comorbid psychopathology and also act as a catalyst for growth following natural disaster events.

Purpose: Pediatric high-grade glioma (pHGG) diagnosis portends poor prognosis and therapeutic monitoring remains difficult. Tumors release cell-free tumor DNA (cf-tDNA) into cerebrospinal fluid (CSF), allowing for potential detection of tumor-associated mutations by CSF sampling. We hypothesized that direct, electronic analysis of cf-tDNA with a handheld platform (Oxford Nanopore MinION) could quantify patient-specific CSF cf-tDNA variant allele fraction (VAF) with improved speed and limit of detection compared with established methods. Experimental Design: We performed ultra-short fragment (100–200 bp) PCR amplification of cf-tDNA for clinically actionable alterations in CSF and tumor samples from patients with pHGG (n = 12) alongside nontumor CSF (n = 6). PCR products underwent rapid amplicon-based sequencing by Oxford Nanopore Technology (Nanopore) with quantification of VAF. Additional comparison to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) was performed. Results: Nanopore demonstrated 85% sensitivity and 100% specificity in CSF samples (n = 127 replicates) with 0.1 femtomole DNA limit of detection and 12-hour results, all of which compared favorably with NGS. Multiplexed analysis provided concurrent analysis of H3.3A (H3F3A) and H3C2 (HIST1H3B) mutations in a nonbiopsied patient and results were confirmed by ddPCR. Serial CSF cf-tDNA sequencing by Nanopore demonstrated correlation of radiological response on a clinical trial, with one patient showing dramatic multi-gene molecular response that predicted long-term clinical response. Conclusions: Nanopore sequencing of ultra-short pHGG CSF cf-tDNA fragments is feasible, efficient, and sensitive with low-input samples thus overcoming many of the barriers restricting wider use of CSF cf-tDNA diagnosis and monitoring in this patient population.

Patients with H3K27M-mutated diffuse midline glioma (DMG) have no proven effective therapies beyond radiation. ONC201, a DRD2 antagonist and mitochondrial ClpP agonist, has shown promise in this population. Clinical and genetic variables associated with ONC201 response in H3K27M-mutant DMG continue to be investigated. A combined clinical and genetic study evaluated patients with H3K27M-DMG treated with single-agent ONC201 at the established phase 2 dose. Clinical outcomes of patients treated on two recently completed multi-site clinical studies (NCT03416530 and NCT03134131, n = 75) were compared with historical control data from patients with confirmed H3K27M-DMG (n = 391 total, n = 119 recurrent). Patients treated with ONC201 monotherapy following initial radiation, but prior to recurrence, demonstrated a median overall survival (OS) of 25.6 months from diagnosis and recurrent patients demonstrated a median OS of 16.2 months from recurrence, both of these more than doubling historical outcomes. Using a Cox model to correct for age, gender and tumor location, OS of ONC201-treated patients with H3K27M-mutant tumors remained significantly better than non-ONC201-treated historical controls (p = 0.0001). A survival and radiographic analysis based on tumor location, revealed stronger responses in thalamic patients. In patients with thalamic tumors treated after initial radiation (n = 16), median OS was not reached with median follow up of 22.1 months (historical control median OS of 12.5 months, n = 83, p = 0.0001). Significant correlations were found between baseline cerebral blood flow (CBF) on perfusion imaging and OS (Pearson’s r = 0.75, p = 0.003) and between nrCBF and PFS (r = 0.77, p = 0.002). Baseline tumor sequencing from treated patients (n = 20) demonstrates EGFR mutation (n = 3) and high EGFR expression as a marker of resistance and improved response in tumors with MAPK-pathway alterations (n = 5). In conclusion, ONC201 demonstrates unprecedented clinical and radiographic efficacy in H3K27M-mutant DMG with outcomes enriched in patients with thalamic tumors, treatment prior to recurrence, MAPK-pathway alterations, and patients with relatively high CBF.

Effective pandemic response has become an increasingly important focus for research in the face of the COVID-19 pandemic. While there are a number of variables that may be considered as influencing effective response, this paper focuses on the potential impact of an “authoritarian advantage” in achieving an effective response in the period prior to pharmaceutical interventions being available with China as a case study. In essence, this paper explores whether China enjoys an authoritarian advantage, and if so, how it functions. This study compares China’s SARS-CoV-1 (2003) response with its SARS-CoV-2 (2019) response by exploring the impact of the authoritarian advantage on the state’s ability to effectively engage three key explanatory variables — centralized decision-making powers, public support and media engagement.

Chirality is a geometrical property described by continuous mathematical functions.1–5 However, in chemical disciplines chirality is often treated as a binary left/right characteristic of molecules rather than a continuity of chiral shapes. While being theoretically possible, a family of stable chemical structures with the same shape and progressively tunable chirality is yet unknown. Here we present such structures in the form of nanostructured microparticles with anisotropic bowtie shape and widely tunable twist angle, pitch, size, thickness, and length. The self-limited assembly of the bowties enables high synthetic reproducibility, size monodispersity, and computational predictability of their geometries for different assembly conditions.6 The bowties nanoassemblies display multiple strong circular dichroism peaks originating from absorptive and scattering phenomena. Unlike classical chiral molecules, these particles display a continuum of chirality measures2 that correlate exponentially with the spectral positions of the circular dichroism peaks. Bowtie particles with variable polarization rotation were used to print photonically active metasurfaces with spectrally tunable positive/negative polarization signatures for light detection and ranging (LIDAR) devices.

OBJECTIVEGlioblastoma (GBM) during infancy is rare, and the clinical outcomes of congenital GBM are not well understood. Correspondingly, the aim of this study was to present a long-term survivor case from the authors’ institution, and establish an integrated cohort of cases across the published literature to better understand the clinical course of this disease in this setting.METHODSThe authors report the outcomes of an institutional case of congenital GBM diagnosed within the first 3 months of life, and performed a comprehensive literature search for published cases from 2000 onward for an integrated survival analysis. All cases were integrated into 1 cohort, and Kaplan-Meier estimations, Fisher’s exact test, and logistic regression were used to interrogate the data.RESULTSThe integrated cohort of 40 congenital GBM cases consisted of 23 (58%) females and 17 (42%) males born at a median gestational age of 38 weeks (range 22–40 weeks). Estimates of overall survival (OS) at 1 month was 67%, at 1 year it was 59%, and at 10 years it was 45%, with statistically superior outcomes for subgroups in which patients survived to be treated by resection and chemotherapy. In the overall cohort, multivariable analysis confirmed resection (p < 0.01) and chemotherapy (p < 0.01) as independent predictors of superior OS. Gestational age > 38 weeks (p < 0.01), Apgar scores ≥ 7 at 5 minutes (p < 0.01), absence of prenatal hydrocephalus (p < 0.01), and vaginal delivery (p < 0.01) were associated with greater odds of surgical diagnosis versus autopsy diagnosis.CONCLUSIONSCongenital GBM can deviate from the expected poor prognosis of adult GBM in terms of OS. Both resection and chemotherapy confer statistically superior prognostic advantages in those patients who survive within the immediate postnatal period, and should be first-line considerations in the initial management of this rare disease.

Electron tomography has achieved higher resolution and quality at reduced doses with recent advances in compressed sensing. Compressed sensing (CS) theory exploits the inherent sparse signal structure to efficiently reconstruct three-dimensional (3D) volumes at the nanoscale from undersampled measurements. However, the process bottlenecks 3D reconstruction with computation times that run from hours to days. Here we demonstrate a framework for dynamic compressed sensing that produces a 3D specimen structure that updates in real-time as new specimen projections are collected. Researchers can begin interpreting 3D specimens as data is collected to facilitate high-throughput and interactive analysis. Using scanning transmission electron microscopy (STEM), we show that dynamic compressed sensing accelerates the convergence speed by 3-fold while also reducing its error by 27% for an Au/SrTiO3 nanoparticle specimen. Before a tomography experiment is completed, the 3D tomogram has interpretable structure within 33% of completion and fine details are visible as early as 66%. Upon completion of an experiment, a high-fidelity 3D visualization is produced without further delay. Additionally, reconstruction parameters that tune data fidelity can be manipulated throughout the computation without rerunning the entire process.

Although recurrent anaplastic ependymoma in pediatric patients is not uncommon, recurrent disease leading to widespread metastases to the peritoneum is extremely rare. We present a case of an 18-month old male who initially presented with posterior fossa anaplastic ependymoma, who then proceeded to present 1 year later with spinal recurrence, and then 2 years after that with widespread disease involving the intracranial ventricular system and peritoneum. We posit that surgical interventions to treat primary and recurrent presentations in combination with a conduit to the peritoneum via a ventriculoperitoneal shunt contributed to the mechanisms of this complex case.

The COVID-19 outbreak has drawn heightened attention from public health scholars researching ways to limit its spread. Much of the research has been focused on minimizing transmission in hospitals and in the general community. However, a particularly vulnerable community that has received relatively little attention is elders residing in long-term care facilities (LTCFs). In this article we address this relative lack of attention, arguing that enhanced traffic control bundling (eTCB) can and should be adopted and implemented as a means of protecting LTCF residents and staff. Enhanced TCB has been widely applied in hospital settings and has proven effective at limiting droplet and fomite transmissions both within hospitals and between hospitals and the general community. By effectively adapting eTCB to LTCF conditions, particularly by incorporating compartmentalization within zones plus active surveillance, COVID-19 transmission into and throughout LTCFs can be minimized, thereby saving numerous lives among an especially vulnerable population.

The demand for high-throughput electron tomography is rapidly increasing in biological and material sciences. However, this 3D imaging technique is computationally bottlenecked by alignment and reconstruction which runs from hours to days. We demonstrate real-time tomography with dynamic 3D tomographic visualization to enable rapid interpretation of specimen structure immediately as data is collected on an electron microscope. We show volumetric interpretation can begin in less than 10 minutes and a high-quality tomogram is available within 30 minutes. Real-time tomography is integrated into tomviz, an open-source and cross-platform 3D data analysis tool that contains intuitive graphical user interfaces (GUI), to enable any scientist to characterize biological and material structure in 3D.