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Short-term probabilistic forecasts of the trajectory of the COVID-19 pandemic in the United States have served as a visible and important communication channel between the scientific modeling community and both the general public and decision-makers. Forecasting models provide specific, quantitative, and evaluable predictions that inform short-term decisions such as healthcare staffing needs, school closures, and allocation of medical supplies. Starting in April 2020, the US COVID-19 Forecast Hub (https://covid19forecasthub.org/) collected, disseminated, and synthesized tens of millions of specific predictions from more than 90 different academic, industry, and independent research groups. A multimodel ensemble forecast that combined predictions from dozens of groups every week provided the most consistently accurate probabilistic forecasts of incident deaths due to COVID-19 at the state and national level from April 2020 through October 2021. The performance of 27 individual models that submitted complete forecasts of COVID-19 deaths consistently throughout this year showed high variability in forecast skill across time, geospatial units, and forecast horizons. Two-thirds of the models evaluated showed better accuracy than a naïve baseline model. Forecast accuracy degraded as models made predictions further into the future, with probabilistic error at a 20-wk horizon three to five times larger than when predicting at a 1-wk horizon. This project underscores the role that collaboration and active coordination between governmental public-health agencies, academic modeling teams, and industry partners can play in developing modern modeling capabilities to support local, state, and federal response to outbreaks.

An increasing number of treatment guidelines recommend rapid initiation of antiretroviral therapy (ART) after the diagnosis of human immunodeficiency virus (HIV) infection. However, data on the association between rapid ART initiation and alterations in brain structure and function remain limited in people with HIV (PWH). A cross-sectional analysis was conducted on HIV-positive men who have sex with men (MSM) undergoing ART. Fifty-four participants who started ART within 30 days of confirmed HIV diagnosis (rapid ART group) and 20 participants who started ART more than 6 months of confirmed HIV diagnosis (non-rapid ART group) completed clinical assessments and multimodal magnetic resonance imaging scans to obtain both anatomical and resting-state functional images. Compared to PWH in the non-rapid ART group, those in the rapid ART group exhibited a greater total gray matter volume (P = 0.001) and functional changes, including a lower amplitude of low-frequency fluctuations in the left angular gyrus (P < 0.001). Moreover, the results of the main effects and interactions indicated that rapid ART initiation had main effects on major imaging outcomes. The validation analysis results in participants who started ART within 7 days of confirmed HIV diagnosis generally corroborated and complemented the aforementioned findings. Our study demonstrated brain gray matter volume atrophy and functional alterations in PWH of the non-rapid ART group compared to those in the rapid ART group, suggesting that rapid ART initiation may be associated with better brain structure and function changes in HIV-positive MSM. [ABSTRACT FROM AUTHOR]

To evaluate the effects of different TiO2 crystalline phases on the catalytic oxidation performance of benzene on Pt-loaded TiO2 catalysts, physicochemical examinations were conducted using several spectroscopic and analytical techniques. Obvious effects on the valence state and morphology of Pt were exhibited by different crystalline phases. The rutile phase favored the formation of specific Pt(111) crystal faces, which enhanced the amount of surface-active oxygen species. Moreover, the àPt-O-Ti species was formed between Pt4+ and Ti at the edge of the Pt nanoparticles, promoting both electron flow and the transfer of reactive oxygen species, thus accounting for catalytic activity. [ABSTRACT FROM AUTHOR]

The condition of the root system affects the quality of seedlings in forestry and horticulture. Previously, the electrical impedance loss factor (δ) and the reverse‐flow hydraulic conductance (Kr) of the roots of Scots pine seedlings were found to increase when assessed a few days after frost damage. How these variables change with time after the root damage is unknown. We arranged an experiment with 1.5‐year‐old Scots pine seedlings exposed to −5°C or − 30°C, with the control seedlings kept at 3°C. Then, δ and Kr of roots were monitored for 5 weeks in favorable growing conditions. The properties of the roots were observed to be in a dynamic state after the damage. A significant difference in δ was found between the test temperatures −30°C versus −5°C and 3°C (p = 0.004 and p < 0.001, respectively). The clearest effect of freezing injuries on δ of roots was observed in the first measurement 1 week after the freezing test. The temperature significantly affected Kr, too, with a significant difference between the low‐temperature treated plants −30°C versus −5°C and control (p < 0.001, respectively). The difference in Kr between −30°C and the other two temperatures increased with time and was the largest in the last samples, taken after 5 weeks. We conclude that the impedance loss factor may detect root damage if the measurements occur early enough after the damage, but a longer time difference (3–5 weeks) is needed according to the reverse‐flow hydraulic conductance. [ABSTRACT FROM AUTHOR]

Phase change material (PCM) and hygroscopic material (HM) in building walls are promising passive technologies for temperature and humidity regulation, respectively. Integrating the two materials allows for hygrothermal environment regulation and energy savings. However, the joint effect of the temperature dependence of the HM's hygroscopic properties and the location dependence of the PCM's thermal properties has not been mentioned or demonstrated. This study experimentally assessed the hygrothermal and energy performance of a shell enclosed by a PCM-HM wall. Different wall scenarios were proposed to study the effect of the HM, PCM, and PCM's location. The results highlighted the dominance of temperature and the significance of the PCM on performance. For PCM walls, the thermal and hygric inertia were enhanced, the characteristic times of temperature/relative humidity were increased, and the variation was dampened. Under a sinusoidally varying climate, the peak temperature, thermal load, and fluctuations in temperature, relative humidity, and vapor pressure were reduced, and the peak temperature was delayed. Additionally, the repositioning of the PCM further improved the performance. When the PCM was repositioned from the outside to the middle, the temperature, relative humidity, vapor pressure fluctuations, and thermal load were reduced by 25.0 %, 45.8 %, 54.6 %, and 33.1 %, respectively, in warm to hot climates, and by 12.5 %, 63.6 %, 41.9 %, and 66.0 %, respectively, in cold to temperate climates. The PCM properties are important as the PCM in the PCM-middle wall has a higher melt fraction in the solid–liquid state, which utilizes more PCM latent heat energy and improves wall performance. • Bio-based hygroscopic material and PCM were integrated as a novel building wall. • Hygrothermal and energy performance were studied and assessed experimentally. • The presence of the PCM improved the hygrothermal and energy performance. • The repositioning of the PCM can further improve the performance. • PCMs at different locations in the wall have different latent heat utilization. [ABSTRACT FROM AUTHOR]

The synthesis of polymer-protein nanostructures opens up a new avenue for the development of new biomaterials. In this research, covalently connected polymer-protein nanostructures were fabricated through a reactive self-assembly approach. Poly( tert-butyl methacrylate- co-pyridyl disulfide methacrylamide) (P tBMA- co-PPDSMA) was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. Covalently connected nanostructures (CCNs) with hydrophobic polymer cores and hydrophilic protein coronae were prepared by adding solutions of P tBMA- co-PPDSMA/DMF to aqueous solutions of bovine serum albumin (BSA). The thiol-disulfide exchange reaction between pyridyl disulfide groups on the polymer chains and thiol groups on the protein molecules plays a key role in the fabrication of CCNs. The self-assembly process was investigated by dynamic light scattering (DLS) and stopped-flow techniques. DLS results indicated that the sizes of the CCNs were determined by the initial polymer concentration, the BSA concentration, and the average number of thiol groups on BSA molecules. TEM and sodium dodecyl sulfate polyacrylamide gel electrophoresis were used to analyze the nanostructures. Far-UV circular dichroism results demonstrated that the original folded conformations of BSA molecules were basically maintained in the reactive self-assembly process. Compared with native BSA, the secondary structure and conformation change of coronal BSA induced by urea or thermal treatment were remarkably suppressed. The cytotoxicity assays demonstrated that the CCNs were essentially nontoxic to Hela and COS-7 cells. [ABSTRACT FROM AUTHOR]

Serralysin is a well studied metalloprotease, and typical serralysins are not thermostable. The serralysin isolated from Serratia sp. FS14 was found to be thermostable, and in order to reveal the mechanism responsible for its thermostability, the crystal structure of serralysin from Serratia sp. FS14 was solved to a crystallographic R factor of 0.1619 at 1.10 Å resolution. Similar to its homologues, it mainly consists of two domains: an N-terminal catalytic domain and a `parallel β-roll' C-terminal domain. Comparative studies show that the shape of the catalytic active-site cavity is more open owing to the 189-198 loop, with a short 310-helix protruding further from the molecular surface, and that the β-sheets comprising the `parallel β-roll' are longer than those in its homologues. The formation of hydrogen bonds from one of the nonconserved residues (Asn200) to Lys27 may contribute to the thermostability. [ABSTRACT FROM AUTHOR]

Confined to one cell: A method to detect and isolate single circulating melanoma cells (CMCs; see figure) has been produced by integrating a polymer‐nanofiber‐embedded nanovelcro cell‐affinity assay with a laser microdissection (LMD) technique. This method is able to separate CMCs from normal white blood cells (WBCs) and sequence individual cells for a specific mutation related to cancer progression, allowing for more personalized cancer therapy. [ABSTRACT FROM AUTHOR]

We report here the modulation of a peptide assembly with a molecular template at the liquid–solid interface using scanning tunneling microscopy (STM). A lamella structure is observed for the assembly of pentapeptide 5Ala, and the introduction of the terpyridine derivative (BT–O–C16) gives rise to co-assembled molecular architectures with pentapeptide monomers and dimers encapsulated in the nanoscale cavities of the BT–O–C16 network. The selectivity of the molecular networks could allow for programmable construction of organic–peptide architectures. [ABSTRACT FROM AUTHOR]

The transcription factor nuclear factor erythroid 2 p45-related factor 2 (Nrf2), a major regulator of genes encoding Phase II detoxifying enzymes and antioxidant proteins, is important for protecting cells against oxidative damage. In this work, we report that in the immune-mediated motor neuron injury animal model, expression of Nrf2 and antioxidative enzymes including glutathione S-transferase, nicotinamide adenine dinucleotide phosphate (reduced)-quinone oxidoreductase 1 and heme oxygenase 1 were greatly reduced in motor neurons of spinal cord anterior horn in paralyzed guinea pigs, whereas the antioxidant enzymes in the dorsal horn of paralyzed guinea pigs were generally preserved. Our findings suggest that declined antioxidative capacity may contribute to the damage to motor neurons in the process of immune-mediated motor neuron injury. Although the exact mechanism of immune reactivity and Nrf2-antioxidant response element pathway inactivation remains to be elucidated, inducers of Phase II detoxification enzymes may be an attractive therapeutic target for immune-mediated motor neuron degeneration. [ABSTRACT FROM AUTHOR]

Reactive astrogliosis has been found in the cerebral cortex and spinal cord in amyotrophic lateral sclerosis, whereas astrocytic pathology in immune-mediated motor neuron injury has not been reported. On the basis of the establishment of an immune-mediated motor neuron injury model, histological, immunohistochemical and ultrastructural studies on astrocytes were carried out. Reactive astrogliosis in spinal cord anterior horn was observed, and the increase of GFAP-positive astrocytes may occur prior to the clinical manifestations. Reactive astrocytes could show pathological changes similar to those of motor neurons, such as swollen mitochondria and dilated endoplasmic reticulum. Of special interest are crystallized inclusions that were frequently observed in the reactive astrocytes in the bovine ventral horn homogenate-immunized anterior horn. The precise nature and origin of these inclusions deserve to be elucidated. [ABSTRACT FROM AUTHOR]