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President Joe Biden has muscled through the highest number of federal judges in the first year of a presidency in four decades, rapidly filling vacancies at a clip that outpaces [...]

Continuous synthesis of high-crystalline carbon nanotubes (CNTs) is achieved by reconfiguring the injection part in the reactor that is used in the floating catalyst chemical vapor deposition (FC-CVD) process. The degree of gas mixing is divided into three cases by adjusting the configuration of the injection part: Case 1: most-delayed gas mixing (reference experiment), Case 2: earlier gas mixing than Case 1, Case 3: earliest gas mixing. The optimal synthesis condition is obtained using design of experiment (DOE) in the design of Case 1, and then is applied to the other cases to compare the synthesis results. In all cases, the experiments are performed by varying the timing of gas mixing while keeping the synthesis conditions constant. Production rate (Case 1: 0.63 mg/min, Case 2: 0.68 mg/min, Case 3: 1.29 mg/min) and carbon content (Case 1: 39.6 wt%, Case 2: 57.1 wt%, Case 3: 71.6 wt%) increase as the gas-mixing level increases. The amount of by-products decreases stepwise as the gas-mixing level increases. The IG/IDratio increases by a factor of 7 from 10.3 (Case 1) to 71.7 (Case 3) as the gas-mixing level increases; a high ratio indicates high-crystalline CNTs. The radial breathing mode (RBM) peak of Raman spectrograph is the narrowest and sharpest in Case 3; this result suggests that the diameter of the synthesized CNTs is the most uniform in Case 3. This study demonstrates the importance of configuration of the injection part of the reactor for CNT synthesis using FC-CVD.

The White House is requesting approximately $4 billion in emergency funding from Congress to address the collapse and repair of the Francis Scott Key bridge in Baltimore, as well as other recent disasters in the United States. This request is an addition to a previous $56 billion ask from last October that was largely ignored by Congress. The Biden administration is seeking an additional $3.1 billion for the Department of Transportation to rebuild the Key Bridge, with the federal government covering the entire cost. The remaining funds would be allocated to the Coast Guard and the Army Corps of Engineers for expenses related to the bridge collapse. The request also includes funding for other disasters, such as tornadoes in the Midwest and wildfires in Hawaii. The bridge collapse occurred after a cargo ship, which had experienced electrical blackouts, struck the bridge, resulting in the deaths of six construction workers. [Extracted from the article]

Sudomotor dysfunction is common in patients with multiple system atrophy (MSA). Postganglionic sudomotor dysfunction in MSA, which can be assessed using quantitative sudomotor axon reflex testing (QSART), results from the degeneration of preganglionic sympathetic neurons and direct loss of postganglionic fibers. We investigate whether abnormal QSART responses in patients with MSA are associated with disease severity. In this retrospective study, patients with probable MSA who underwent both 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) and autonomic function tests were included. Autonomic function test results were integrated divided into three sub-scores, including sudomotor, cardiovagal, and adrenergic sub-scores. The sudomotor sub-score represented postganglionic sudomotor function. Unified Multiple System Atrophy Rating Scale (UMSARS) Part I, Part II, and sum of Part I and II scores (Part I + II) to reflect disease severity and 18F-FDG-PET/CT results were collected. Of 74 patients with MSA, 62.2%demonstrated abnormal QSART results. The UMSARS Part I + II score was significantly higher in the abnormal QSART group than in the normal QSART group (p = 0.037). In the regression analysis, both UMSARS Part I (β= 1.185, p = 0.013) and Part II (β= 1.266, p = 0.021) scores were significantly associated with the sudomotor sub-score. On 18F-FDG-PET/CT, the abnormal QSART group exhibited more severely decreased metabolic activity in the cerebellum and basal ganglia in patients with MSA-P and MSA-C, respectively. The sudomotor sub-score was significantly associated with regional metabolism in these areas. Patients with MSA and postganglionic sudomotor dysfunction may have worse disease severity and greater neuropathological burden than those without.

Sodium yttrium fluoride (NaYF4) is an important upconverting material with many potential uses in chemistry, materials science, and biology, which can be synthesized hydrothermally in both cubic (α) and hexagonal (β) crystallographic polymorphs. Understanding the mechanisms underlying the phase conversion between the cubic and hexagonal polymorphs is of great interest to help inform future synthetic efforts, for example in the design of atomically precise quantum materials with well-defined sizes and morphologies. In this work, we use a combination of analytical transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), powder X-ray diffraction (XRD), in situ liquid cell TEM, atom probe tomography (APT), and extended X-ray absorption fine structure (EXAFS) measurements to show that the hexagonal NaYF4nanowires form through a nonclassical crystal growth mechanism involving the formation and subsequent oriented attachment of mesocrystals consisting of cubic (α) phase units. EXAFS measurements also suggest that substitutional Yb3+point defects within NaYF4are distributed evenly throughout the crystal lattice without clustering and also that they may exhibit selective substitution into one of the two possible trivalent yttrium sites in the unit cell for hydrothermally synthesized β-NaYF4.

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This paper reports on the experimental investigations on the failure modes of ring-stiffened cylinder models subjected to external hydrostatic pressure. Nine models were welded from general structural steel. The shells were initially formed by cold-rolling, and flat-bar ring frames were welded to the shell. The hydrostatic pressure tests were conducted by using water as the medium in pressure chambers. The details of the preparation and main test were briefly explained. The investigation identified the consequence of the structural failure modes, including: shell yielding, local shell buckling between ring stiffeners, overall buckling of the shell together with the stiffeners, and interactive buckling mode combining local and overall buckling. In addition, the ultimate strengths were predicted by using existing design codes. Non-linear numerical computations were also conducted by employing the actual imperfection coordinates. Finally, accuracy and reliability of the predictions of design formulae and numerical were substantiated with the test results.

Three cyclic lipopeptides, including one known (1) and two new (2and 3) compounds, that possess the rare enamide linkage group were discovered from Streptomycessp. KCB14A132, an actinobacterium isolated from a soil sample collected from Jeung Island, Korea. The NMR and MS-based characterization showed that they differed in the amino acid residues in the peptide backbone. Application of Marfey’s analysis, GITC derivatization, and modified Mosher’s method, as well as ECD measurements provided the absolute configurations of enamidonin (1) and those of new compounds enamidonins B and C (2and 3). The two new enamidonin analogues were shown to exhibit antibacterial activity against Gram-positive bacteria including methicillin-resistant and quinolone-resistant Staphylococcus aureus. Furthermore, evaluation of the extraction conditions and a close inspection of the LC-MS chromatograms revealed that the N,N-acetonide unit of the enamidonin family was formed during the acetone extraction process. The chemically prepared deacetonide derivatives of enamidonins were found to lack antibacterial activity, demonstrating that the dimethylimidazolidinone residue is necessary for antibacterial activity.

Cas9 ribonucleoprotein (RNP)-mediated delivery has emerged as an ideal approach for in vivoapplications. However, the delivery of Cas9 RNPs requires electroporation or lipid- or cationic-reagent-mediated transfection. Here, we developed a carrier-free Cas9 RNP delivery system for robust gene editing in vivo. For simultaneous delivery of Cas9 and a guide RNA into target cells without the aid of any transfection reagents, we established a multifunctional Cas9 fusion protein (Cas9-LMWP) that forms a ternary complex with synthetic crRNA:tracrRNA hybrids in a simple procedure. Cas9-LMWP carrying both a nuclear localization sequence and a low-molecular-weight protamine (LMWP) enables the direct self-assembly of a Cas9:crRNA:tracrRNA ternary complex (a ternary Cas9 RNP) and allows for the delivery of the ternary Cas9 RNPs into the recipient cells, owing to its intrinsic cellular and nuclear translocation ability with low immunogenicity. To demonstrate the potential of this system, we showed extensive synergistic anti-KRAS therapy (CI value: 0.34) via in vitroand in vivoediting of the KRASgene by the direct delivery of multifunctional Cas9 RNPs in lung cancer. Thus, our carrier-free Cas9 RNP delivery system could be an innovative platform that might serve as an alternative to conventional transfection reagents for simple gene editing and high-throughput genetic screening.

In this study, we propose a method for improving the stability of multilayer MoS2field-effect transistors (FETs) by O2plasma treatment and Al2O3passivation while sustaining the high performance of bulk MoS2FET. The MoS2FETs were exposed to O2plasma for 30 s before Al2O3encapsulation to achieve a relatively small hysteresis and high electrical performance. A MoOxlayer formed during the plasma treatment was found between MoS2and the top passivation layer. The MoOxinterlayer prevents the generation of excess electron carriers in the channel, owing to Al2O3passivation, thereby minimizing the shift in the threshold voltage (Vth) and increase of the off-current leakage. However, prolonged exposure of the MoS2surface to O2plasma (90 and 120 s) was found to introduce excess oxygen into the MoOxinterlayer, leading to more pronounced hysteresis and a high off-current. The stable MoS2FETs were also subjected to gate-bias stress tests under different conditions. The MoS2transistors exhibited negligible decline in performance under positive bias stress, positive bias illumination stress, and negative bias stress, but large negative shifts in Vthwere observed under negative bias illumination stress, which is attributed to the presence of sulfur vacancies. This simple approach can be applied to other transition metal dichalcogenide materials to understand their FET properties and reliability, and the resulting high-performance hysteresis-free MoS2transistors are expected to open up new opportunities for the development of sophisticated electronic applications.

Here, we take advantage of in situtransmission electron microscopy (TEM) to investigate the thermal stability of P2-type NaxCoO2cathode materials for sodium ion batteries, which are promising candidates for next-generation lithium ion batteries. A double-tilt TEM heating holder was used to directly characterize the changes in the morphology and the crystallographic and electronic structures of the materials with increase in temperature. The electron diffraction patterns and the electron energy loss spectra demonstrated the presence of cobalt oxides (Co3O4, CoO) and even metallic cobalt (Co) at higher temperatures as a result of reduction of Co ions and loss of oxygen. The bright-field TEM images revealed that the surface of NaxCoO2becomes porous at high temperatures. Higher cutoff voltages result in degrading thermal stability of NaxCoO2. The observations herein provide a valuable insight that thermal stability is one of the important factors to be considered in addition to the electrochemical properties when developing new electrode materials for novel battery systems.

•Cortical involvement may exist in aquaporin-4-antibody-positive patients.•Conventional imaging is limited in evaluating cortical involvement.•Double inversion recovery imaging can help determine the location of the lesion.