The development of quantum networks will be paramount towards practical and secure telecommunications. These networks will need to sign and distribute information between many parties with ...information-theoretic security, requiring both quantum digital signatures (QDS) and quantum key distribution (QKD). Here, we introduce and experimentally realise a quantum network architecture, where the nodes are fully connected using a minimum amount of physical links. The central node of the network can act either as a totally untrusted relay, connecting the end users via the recently introduced measurement-device-independent (MDI)-QKD, or as a trusted recipient directly communicating with the end users via QKD. Using this network, we perform a proof-of-principle demonstration of QDS mediated by MDI-QKD. For that, we devised an efficient protocol to distil multiple signatures from the same block of data, thus reducing the statistical fluctuations in the sample and greatly enhancing the final QDS rate in the finite-size scenario.
During the third trimester, the human brain undergoes rapid cellular and molecular processes that reshape the structural architecture of the cerebral cortex. Knowledge of cortical differentiation ...obtained predominantly from histological studies is limited in localized and small cortical regions. How cortical microstructure is differentiated across cortical regions in this critical period is unknown. In this study, the cortical microstructural architecture across the entire cortex was delineated with non-Gaussian diffusion kurtosis imaging as well as conventional diffusion tensor imaging of 89 preterm neonates aged 31–42 postmenstrual weeks. The temporal changes of corticalmean kurtosis (MK) or fractional anisotropy (FA) were heterogeneous across the cortical regions. Cortical MK decreases were observed throughout the studied age period, while cortical FA decrease reached its plateau around 37 weeks. More rapid decreases in MK were found in the primary visual region, while faster FA declines were observed in the prefrontal cortex. We found that distinctive cortical microstructural changes were coupled with microstructural maturation of associated white matter tracts. Both cortical MK and FA measurements predicted the postmenstrual age of preterm infants accurately. This study revealed a differential 4D spatiotemporal cytoarchitectural signature inferred by non-Gaussian diffusion barriers inside the cortical plate during the third trimester. The cytoarchitectural processes, including dendritic arborization and neuronal density decreases, were inferred by regional cortical FA and MK measurements. The presented findings suggest that cortical MK and FA measurements could be used as effective imaging markers for cortical microstructural changes in typical and potentially atypical brain development.
About half of Americans 50 to 75 years old do not follow recommended colorectal cancer (CRC) screening guidelines, leaving 40 million individuals unscreened. A simple blood test would increase ...screening compliance, promoting early detection and better patient outcomes. The objective of this study is to demonstrate the performance of an improved sensitivity blood-based Septin 9 (SEPT9) methylated DNA test for colorectal cancer. Study variables include clinical stage, tumor location and histologic grade.
Plasma samples were collected from 50 untreated CRC patients at 3 institutions; 94 control samples were collected at 4 US institutions; samples were collected from 300 colonoscopy patients at 1 US clinic prior to endoscopy. SEPT9 methylated DNA concentration was tested in analytical specimens, plasma of known CRC cases, healthy control subjects, and plasma collected from colonoscopy patients.
The improved SEPT9 methylated DNA test was more sensitive than previously described methods; the test had an overall sensitivity for CRC of 90% (95% CI, 77.4% to 96.3%) and specificity of 88% (95% CI, 79.6% to 93.7%), detecting CRC in patients of all stages. For early stage cancer (I and II) the test was 87% (95% CI, 71.1% to 95.1%) sensitive. The test identified CRC from all regions, including proximal colon (for example, the cecum) and had a 12% false-positive rate. In a small prospective study, the SEPT9 test detected 12% of adenomas with a false-positive rate of 3%.
A sensitive blood-based CRC screening test using the SEPT9 biomarker specifically detects a majority of CRCs of all stages and colorectal locations. The test could be offered to individuals of average risk for CRC who are unwilling or unable to undergo colonscopy.
In the extracellular environment, cell-free virions seek out naive host cells over long distances and between organisms. This is the primary mechanism of spread for most viruses. Here we provide ...evidence for an alternative pathway previously undescribed for orthomyxoviruses, whereby the spread of influenza A virus (IAV) infectious cores to neighboring cells can occur within intercellular connections. The formation of these connections requires actin dynamics and is enhanced by viral infection. Connected cells have contiguous membranes, and the core infectious viral machinery (RNP and polymerase) was present inside the intercellular connections. A live-cell movie of green fluorescent protein (GFP)-tagged NS1 of IAV shows viral protein moving from one cell to another through an intercellular connection. The movement of tagged protein was saltatory but overall traveled only in one direction. Infectious virus cores can move from one cell to another without budding and release of cell-free virions, as evidenced by the finding that whereas a neuraminidase inhibitor alone did not inhibit the development of IAV microplaques, the presence of a neuraminidase inhibitor together with drugs inhibiting actin dynamics or the microtubule stabilizer paclitaxel (originally named taxol) precluded microplaque formation. Similar results were also observed with parainfluenza virus 5 (PIV5), a paramyxovirus, when neutralizing antibody was used to block spread by cell-free virions. Intercellular spread of infectious core particles was unaffected or enhanced in the presence of nocodazole for IAV but inhibited for PIV5. The intercellular connections have a core of filamentous actin, which hints toward transport of virus particles through the use of a myosin motor.
Here we describe a new method by which influenza A virus (IAV) spreads from cell to cell: IAV uses intracellular connections. The formation of these connections requires actin dynamics and is enhanced by viral infection and the absence of microtubules. Connected cells appeared to have contiguous membranes, and the core infectious viral machinery (RNP and polymerase) was present inside the intercellular connections. Infectious virus cores can move from one cell to another without budding and release of cell-free virions. Similar results were also observed with parainfluenza virus 5 (PIV5).
To present updated national birthweight percentiles by gestational age for male and female singleton infants born in Australia.
Cross-sectional population-based study of 2.53 million singleton live ...births in Australia between 1998 and 2007.
Birthweight percentiles by gestational age and sex.
Between 1998 and 2007, women in Australia gave birth to 2 539 237 live singleton infants. Of these, 2 537 627 had a gestational age between 20 and 44 weeks, and sex and birthweight data were available. Birthweight percentiles are presented by sex and gestational age for a total of 2 528 641 births, after excluding 8986 infants with outlying birthweights. Since the publication of the previous Australian birthweight percentiles in 1999, median birthweight for term babies has increased between 0 and 25 g for boys and between 5 g and 45 g for girls.
There has been only a small increase in birthweight percentiles for babies of both sexes and most gestational ages since 1991-1994. These national percentiles provide a current Australian reference for clinicians and researchers assessing weight at birth.
In aqueous electrochemical processes, the pH evolves spatially and temporally, and often dictates the process performance. Herein, a new method for the in‐operando monitoring of pH distribution in an ...electrochemical cell is demonstrated. A combination of pH‐sensitive fluorescent dyes, encompassing a wide pH range from ≈1.5 to 8.5, and rapid electrochemically coupled laser scanning confocal microscopy is used to observe pH changes in the cell. Using electrocoagulation as an example process, we show that the method provides new insights into the reaction mechanisms. The pH close to the aluminium electrode surface is influenced by the applied current density, hydrolysis of aluminium cations, and gas evolution. Through quantification of the pH at the anode, along with gas analysis, we find that hydrogen is evolved at the anode due to a non‐Faradaic chemical reaction. This leads to increased production of coagulant, which may open new routes to enhance the process performance. This method for in‐operando dynamic visualization of pH paves the way for studies of electrochemical processes, including other water treatment, electrosynthesis, and batteries.
Spatially and temporally resolved pH in an electrochemical system was obtained by laser scanning confocal microscopy. A combination of pH sensitive dyes was used to extend the dynamic pH range. This approach can be used to investigate the reaction products and transport phenomena in aqueous electrochemical systems.
Ozone exposure effect on free radical-catalyzed oxidation products of lipids, proteins, and DNA in the plasma and urine of rats was studied as a continuation of the international Biomarker of ...Oxidative Stress Study (BOSS) sponsored by NIEHS/NIH. The goal was to identify a biomarker for ozone-induced oxidative stress and to assess whether inconsistent results often reported in the literature might be due to the limitations of the available methods for measuring the various types of oxidative products. The time- and dose-dependent effects of ozone exposure on rat plasma lipid hydroperoxides, malondialdehyde, F2-isoprostanes, protein carbonyls, methionine oxidation, and tyrosine- and phenylalanine oxidation products, as well as urinary malondialdehyde and F2-isoprostanes were investigated with various techniques. The criterion used to recognize a marker in the model of ozone exposure was that a significant effect could be identified and measured in a biological fluid seen at both doses at more than one time point. No statistically significant differences between the experimental and the control groups at either ozone dose and time point studied could be identified in this study. Tissue samples were not included. Despite all the work accomplished in the BOSS study of ozone, no available product of oxidation in biological fluid has yet met the required criteria of being a biomarker. The current negative findings as a consequence of ozone exposure are of great importance, because they document that in complex systems, as the present in vivo experiment, the assays used may not provide meaningful data of ozone oxidation, especially in human studies.
•The following oxidized molecules in plasma and urine are not markers of ozone: lipid hydroperoxides, MDA, F2-isoprostanes, cholesteryl ester hydroperoxides, HETEs protein carbonyls, methionine sulfoxide, tyrosine products (nitro-, o/m, di), DNA strand breaks, 8-OHdG.
To determine the association of circulating cell-free hemoglobin with poor clinical outcomes in patients with sepsis and to characterize the potential protective effects of acetaminophen, an ...inhibitor of hemoprotein-mediated oxidation.
Retrospective observational study.
A total of 391 critically ill patients with sepsis in multiple ICUs in an academic tertiary care hospital.
None.
Nonsurvivors had significantly higher plasma cell-free hemoglobin concentrations (median 20mg/dL, interquartile range 10-40) measured on enrollment compared to survivors (10mg/dL, interquartile range 10-30, p = 0.002). After controlling for potential confounders, patients with higher cell-free hemoglobin concentrations were significantly more likely to die in the hospital (odds ratio 1.078, 95% confidence interval 1.012-1.149, p = 0.02). In addition, receiving acetaminophen in the setting of increased cell-free hemoglobin was independently associated with a protective effect against death (odds ratio 0.48, 95% confidence interval 0.25-0.91, p = 0.026) and lower plasma concentrations of the lipid peroxidation product F2-isoprostanes (18.5 pg/mL, interquartile range 9-22.2) compared to no acetaminophen (42 pg/mL, interquartile range 29.7-86, p = 0.009).
In critically ill patients with sepsis, elevated concentrations of circulating cell-free hemoglobin are independently associated with an increased risk of death. Acetaminophen may exert a protective effect by reducing cell-free hemoglobin-induced oxidative injury.
Few modifiable risk factors for post-COVID-19 condition (PCC) have been identified.
To investigate the association between healthy lifestyle factors prior to SARS-CoV-2 infection and risk of PCC.
In ...this prospective cohort study, 32 249 women in the Nurses' Health Study II cohort reported preinfection lifestyle habits in 2015 and 2017. Healthy lifestyle factors included healthy body mass index (BMI, 18.5-24.9; calculated as weight in kilograms divided by height in meters squared), never smoking, at least 150 minutes per week of moderate to vigorous physical activity, moderate alcohol intake (5 to 15 g/d), high diet quality (upper 40% of Alternate Healthy Eating Index-2010 score), and adequate sleep (7 to 9 h/d).
SARS-CoV-2 infection (confirmed by test) and PCC (at least 4 weeks of symptoms) were self-reported on 7 periodic surveys administered from April 2020 to November 2021. Among participants with SARS-CoV-2 infection, the relative risk (RR) of PCC in association with the number of healthy lifestyle factors (0 to 6) was estimated using Poisson regression and adjusting for demographic factors and comorbidities.
A total of 1981 women with a positive SARS-CoV-2 test over 19 months of follow-up were documented. Among those participants, mean age was 64.7 years (SD, 4.6; range, 55-75); 97.4% (n = 1929) were White; and 42.8% (n = 848) were active health care workers. Among these, 871 (44.0%) developed PCC. Healthy lifestyle was associated with lower risk of PCC in a dose-dependent manner. Compared with women without any healthy lifestyle factors, those with 5 to 6 had 49% lower risk (RR, 0.51; 95% CI, 0.33-0.78) of PCC. In a model mutually adjusted for all lifestyle factors, BMI and sleep were independently associated with risk of PCC (BMI, 18.5-24.9 vs others, RR, 0.85; 95% CI, 0.73-1.00, P = .046; sleep, 7-9 h/d vs others, RR, 0.83; 95% CI, 0.72-0.95, P = .008). If these associations were causal, 36.0% of PCC cases would have been prevented if all participants had 5 to 6 healthy lifestyle factors (population attributable risk percentage, 36.0%; 95% CI, 14.1%-52.7%). Results were comparable when PCC was defined as symptoms of at least 2-month duration or having ongoing symptoms at the time of PCC assessment.
In this prospective cohort study, pre-infection healthy lifestyle was associated with a substantially lower risk of PCC. Future research should investigate whether lifestyle interventions may reduce risk of developing PCC or mitigate symptoms among individuals with PCC or possibly other postinfection syndromes.
Disruption of circadian rhythms, such as shift work and jet lag, are associated with negative physiological and behavioral outcomes, including changes in affective state, learning and memory, and ...cognitive function. The prefrontal cortex (PFC) is heavily involved in all of these processes. Many PFC-associated behaviors are time-of-day dependent, and disruption of daily rhythms negatively impacts these behavioral outputs. Yet how disruption of daily rhythms impacts the fundamental function of PFC neurons, and the mechanism(s) by which this occurs, remains unknown. Using a mouse model, we demonstrate that the activity and action potential dynamics of prelimbic PFC neurons are regulated by time-of-day in a sex specific manner. Further, we show that postsynaptic K
channels play a central role in physiological rhythms, suggesting an intrinsic gating mechanism mediating physiological activity. Finally, we demonstrate that environmental circadian desynchronization alters the intrinsic functioning of these neurons independent of time-of-day. These key discoveries demonstrate that daily rhythms contribute to the mechanisms underlying the essential physiology of PFC circuits and provide potential mechanisms by which circadian disruption may impact the fundamental properties of neurons.
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