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Methane (CH4), a potent greenhouse gas, plays a pivotal role in the dynamics of climate change. While CH4emissions have been widely investigated, biological removal of CH4by upland soils has been less explored. Understanding the mechanisms and factors affecting CH4oxidation in soils is of paramount importance for devising successful mitigation strategies. This perspective paper discusses different types of aerobic methanotrophs and their activities under varying environmental conditions, highlighting the significant contribution of soil ecosystems to global CH4sinks. We emphasize the need for in-depth research on variables controlling CH4sinks on different spatiotemporal scales and the exploration of previously unidentified CH4sinks, such as deserts and areas of glacier retreat.

As semiconductor scaling continues to reach sub-nanometer levels, two-dimensional (2D) semiconductors are emerging as a promising candidate for the post-silicon material. Among these alternatives, Bi2O2Se has risen as an exceptionally promising 2D semiconductor thanks to its excellent electrical properties, attributed to its appropriate bandgap and small effective mass. However, unlike other 2D materials, growth of large-scale Bi2O2Se films with precise layer control is still challenging due to its large surface energy caused by relatively strong interlayer electrostatic interactions. Here, we present the successful growth of a wafer-scale (∼3 cm) Bi2O2Se film with precise thickness control down to the monolayer level on TiO2-terminated SrTiO3using metal–organic chemical vapor deposition (MOCVD). Scanning transmission electron microscopy (STEM) analysis confirmed the formation of a [BiTiO4]1–interfacial structure, and density functional theory (DFT) calculations revealed that the formation of [BiTiO4]1–significantly reduced the interfacial energy between Bi2O2Se and SrTiO3, thereby promoting 2D growth. Additionally, spectral responsivity measurements of two-terminal devices confirmed a bandgap increase of up to 1.9 eV in monolayer Bi2O2Se, which is consistent with our DFT calculations. Finally, we demonstrated high-performance Bi2O2Se field-effect transistor (FET) arrays, exhibiting an excellent average electron mobility of 56.29 cm2/(V·s). This process is anticipated to enable wafer-scale applications of 2D Bi2O2Se and facilitate exploration of intriguing physical phenomena in confined 2D systems.

6G refers to the communication and services expected to emerge around 2030, coinciding with the convergence of service/terminal evolution and the evolution of mobile communication. Successful implementation of 6G necessitates collaborative efforts from all participants in emerging 6G ecosystems. This includes expanding the range of 6G usage scenarios, selecting appropriate candidate spectrum, and fostering open interfaces. Promising applications for 6G, such as artificial intelligence (AI), sensing, autonomous vehicles (AVs), urban air mobility (UAM), extended reality (XR), holograms, and digital twins, are under discussion. However, the identification of “killer services” unique to 6G and the development of innovative form factor devices are deemed crucial for delivering unprecedented customer experiences. This article reviews key lessons learned from the world's initial 5G commercialization, known as “5G Lessons Learned,” and subsequently presents perspectives on 6G usage scenarios and services anticipated to be implemented by 2030. Notably, simultaneous exploration of new spectrum and refarming of underutilized spec-trum in existing services are highlighted as imperative. As part of this initiative, we provide tangible measurement study results for high-frequency bands considered as potential 6G candidate spectrum.

We present a dynamic random access memory (DRAM) design technology co-optimization (DTCO) methodology that allows the optimization of the DRAM cell structure in the presence of contact resistance variation, trap-assisted tunneling (TAT) leakage variation, and storage node capacitance variation. We showcase our methodology features and results by studying the optimization of a DRAM metal gate work function under the constraints of writeability, retention time (tRET) performance, and robustness to the row hammer effect. Our simulation results show that DRAM performance and its reliability are strongly affected by the contact resistance variations induced by random discrete dopants (RDDs) and can be maximized by means of DTCO-based engineering of contact area and doping concentrations. Our findings also highlight that focusing the optimization on leakage reduction can pay higher dividends than increasing storage node capacitance or improving writeability.

Background: The Korean regulatory authority has enacted legislation to expedite the new drug approval (NDA) process. However, the effectiveness of such efforts in reducing review time and drug approval delays between Korea and the USA/EU remains to be evaluated. Methods: We investigated NDA trends in Korea from 2011 to 2020 using approval information from pharmaceutical companies. We compared the changes in the actual review duration according to active ingredient (chemical vs. biological), orphan status, therapeutic class, and NDA review process. We estimated the submission and approval gaps of new drugs between Korea and the US and EU across the study period. Results: For 235 new drugs, the median NDA review time was 315 days, with a significant increase in the delay (average 15.4 days) over time. Biological drugs had a 43.2-day delay for approval than the time taken for approving chemical drugs. The median NDA review time for orphan drugs was 130.4 days faster than that for others, although the difference diminished after 2016. Good manufacturing practice reviews played a crucial role in delaying review time. The median submission and approval gaps in Korea were 493 and 551 days, respectively, compared to those of the US and EU. Conclusions: Despite recent legislative initiatives, the delay in the NDA review timeline has steadily increased over 10 years in Korea. Delays in orphan drugs reviews increased after the enactment of the ‘Rare Disease Management Act’ in 2016. Careful enforcement of relevant laws and supplementary actions is required to increase new drug accessibility.

South Korea has a long history of the planning, development, and management of smart cities to integrate emerging technological advances into complex physical infrastructure. This article explores lessons learned from smart city programs in South Korea to better understand the challenges and opportunities of future sustainable smart city innovation and development. This article conducted a comprehensive review and analysis of South Korea's smart city programs and conceptualized a sustainable smart city framework that will assist policymakers, planners, citizens, and other key stakeholders. This research proposed Governance, Policy, and Services (GPS) as the three pillars of a successful smart city framework, in addition to integrating physical and cyber infrastructures. This article argues that a smart city should function as a service platform that incubates and delivers long-term services to citizens and society. This article also emphasizes that a strong groundwork of the GPS framework will lead to the successful adaptation of innovative technologies and ideas for future smart city programs.

Molecular spins are emerging platforms for quantum information processing. By chemically tuning their molecular structure, it is possible to prepare a robust environment for electron spins and drive the assembly of a large number of qubits in atomically precise spin-architectures. The main challenges in the integration of molecular qubits into solid-state devices are (i) minimizing the interaction with the supporting substrate to suppress quantum decoherence and (ii) controlling the spatial distribution of the spins at the nanometer scale to tailor the coupling among qubits. Herein, we provide a nanofabrication method for the realization of a 2D patterned array of individually addressable Vanadyl Phthalocyanine (VOPc) spin qubits. The molecular nanoarchitecture is crafted on top of a diamagnetic monolayer of Titanyl Phthalocyanine (TiOPc) that electronically decouples the electronic spin of VOPc from the underlying Ag(100) substrate. The isostructural TiOPc interlayer also serves as a template to regulate the spacing between VOPc spin qubits on a scale of a few nanometers, as demonstrated using scanning tunneling microscopy, X-ray circular dichroism, and density functional theory. The long-range molecular ordering is due to a combination of charge transfer from the metallic substrate and strain in the TiOPc interlayer, which is attained without altering the pristine VOPc spin characteristics. Our results pave a viable route towards the future integration of molecular spin qubits into solid-state devices.

We demonstrate the design and manufacture of RF (radio-frequency) electron linac (linear accelerator) cavity of 6/3 MeV dual-energy X-ray generator for air-cargo security inspections. When an accelerated electron beam collides with the metal target, an X-ray is generated by a bremsstrahlung process. We designed a dual-energy RF cavity using a three-dimensional electromagnetic field simulation code and an electron beam trajectory code. The designed RF cavity is a side-coupled standing-wave type, driven by the π/2 mode, and has a resonant frequency of 2856 MHz. The maximum dose rate of X-ray was calculated to be 7.07 and 0.91 Gy/min at 1 m for an X-ray energy of 6 and 3 MeV using a tungsten target, respectively. In the simulation results, the accelerating gradient was about 13.5 MV/m, the Q-factor was 15,900, and the total length of the RF cavity was 57 cm for 6 MeV of the maximum accelerated electron energy. The resonance frequency and the Q-factor of the fabricated RF cavity were measured by 2855.34 MHz and 14,000, respectively.

Various 3D field physics challenges of magnetically confined plasmas arise when the driving source comes from either externally applied non-axisymmetric 3D magnetic perturbations or plasma instabilities inside the plasma. Recently, several key outstanding topics of 3D field physics have been extensively studied in the Korean Superconducting Tokamak Advanced Research (KSTAR), such as edge-localized-mode (ELM) control by resonant magnetic perturbation (RMP), error field (EF) control, 3D field effects on rotation and transport, and RMP-induced alteration of divertor heat flux and detachment. KSTAR has a few physically unique features (i.e., high rotation and long-pulse plasmas with a low intrinsic EF) and machine/diagnostic capabilities (i.e., 3-row in-vessel control coil and state-of-the-art 2D/3D imaging diagnostics), which have been taken advantage of until now to address critical 3D field physics issues relevant to ITER and K-DEMO. Among many remarkable achievements are the robust access to and control of n= 1 RMP ELM suppression, along with a development of its physics basis tools, parameter expansion, optimization, and long-pulse control techniques. Nonetheless, a series of unresolved 3D physics themes, as well as limited coverage of 3D field operating regimes, have also been identified as future works for the 3D field research in KSTAR. In this paper, we provide an overview about the recent progress of KSTAR 3D field physics and present future plans of KSTAR 3D research toward a future fusion reactor.

Although self-assembly of various peptides has been widely applied, it is challenging to obtain single-crystalline and layer-by-layered nanostructures in a two-dimensional system. Here, we report a method for controlling the morphology and crystal growth at room temperature by a redox-active peptide template that can specifically co-assemble with metal ions. During the crystal growth, a silver ion-coordinated α-helical peptide (+3HN-YYACAYY-COO-) induces long-range atomic ordering at the air/water interface, which leads to multilayered single-crystalline silver nanosheets without an additional annealing process. Furthermore, this peptide template can facilitate efficient electron transfer between the independent metal nanosheets to improve electrochemical properties. We expect that this peptide template-based single-crystal growth method can be extended to synthesize other materials.

Restoration of graft-versus leukemia activity underlies the efficacy of donor lymphocyte infusion (DLI), a curative immunotherapy for leukemic relapse following allogeneic stem cell transplant (SCT). We found that while specific exhausted T cell subsets defined DLI response, no pattern of T cell dysfunction appeared in nonresponders (NRs) [PMID: 34758319]. We hypothesized that leukemic molecular pathways define DLI resistance (DLIr).

Background

Organic–inorganic hybrid layer-by-layer (LBL) composite structures can not only increase the strength and ductility of materials but also well disperse nanomaterials for better-conducting pathways. Here, we discovered the self-assembly process of an organic and silver (Ag) LBL hybrid structure having excellent sustainability during the long-term bending cycle. During the assembly process, the organic and Ag hybrid structure can be self-assembled into a layered structure. Unlike other conventional LBL fabrication processes, we applied the hydrogel scaffold of a biological polymer, which can spontaneously phase separate into an LBL structure in a water/alcohol solvent system. This new hydrogel-based Ag LBL patterns can successfully be printed on a flexible polyimide film without nozzle-clogging problem. Although these Ag LBL patterns cracked during the bending cycle, carbonized organic compounds between the Ag layers help to self-heal within few minutes at a low temperature (<80 °C). On the basis of our new hydrogel-based Ag ink, we could fabricate a fully printed reliable microscale flexible heater. We expect that our self-layering phenomenon can expand to the broad research field of flexible electronics in the near future.

A photoinjector is used as the electron source to generate a high peak current and low emittance beam for an X-ray free electron laser (FEL). The beam emittance is one of the critical parameters to determine the FEL performance together with the slice energy spread and the peak current. The Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL) was constructed in 2015, and the beam commissioning was carried out in spring 2016. The injector is running routinely for PAL-XFEL user operation. The operational parameters of the injector have been optimized experimentally, and these are somewhat different from the originally designed ones. Therefore, we study numerically the injector parameters based on the empirically optimized parameters and review the present operating condition.

Peripheral nerve injury can induce pathological conditions that lead to persistent sensitized nociception. Although there is evidence that plastic changes in the cortex contribute to this process, the underlying molecular mechanisms are unclear. Here, we find that activation of the anterior cingulate cortex (ACC) induced by peripheral nerve injury increases the turnover of specific synaptic proteins in a persistent manner. We demonstrate that neural cell adhesion molecule 1 (NCAM1) is one of the molecules involved and show that it mediates spine reorganization and contributes to the behavioral sensitization. We show striking parallels in the underlying mechanism with the maintenance of NMDA-receptor- and protein-synthesis-dependent long-term potentiation (LTP) in the ACC. Our results, therefore, demonstrate a synaptic mechanism for cortical reorganization and suggest potential avenues for neuropathic pain treatment.

A one-step sub-micrometer-scale electrohydrodynamic (EHD) inkjet three-dimensional (3D)-printing technique that is based on the drop-on-demand (DOD) operation for which an additional postsintering process is not required is proposed. Both the numerical simulation and the experimental observations proved that nanoscale Joule heating occurs at the interface between the charged silver nanoparticles (Ag-NPs) because of the high electrical contact resistance during the printing process; this is the reason why an additional postsintering process is not required. Sub-micrometer-scale 3D structures were printed with an above-35 aspect ratio via the use of the proposed printing technique; furthermore, it is evident that the designed 3D structures such as a bridge-like shape can be printed with the use of the proposed printing technique, allowing for the cost-effective fabrication of a 3D touch sensor and an ultrasensitive air flow-rate sensor. It is believed that the proposed one-step printing technique may replace the conventional 3D conductive-structure printing techniques for which a postsintering process is used because of its economic efficiency.

Abstract: This paper presents a modelling and simulation study of advanced semiconductor devices. Different Technology Computer Aided Design approaches and models, used in nowadays research are described here. Our discussions are based on numerous theoretical approaches starting from first principle methods and continuing with discussions based on more well stablished methods such as Drift-Diffusion, Monte Carlo and Non-Equilibrium Green's Function formalism.

Three materials had highly twisted core structures and m-terphenyl introduced into core. In film state, excimer emission can be interpreted as result of orientation effect. Wavelength of excimer was controlled through change of center position of triple-core chromophore, and CIE of white light and efficiency could be controlled.

We have designed a new compensation film on the basis of the analyses of optical path in various compensation film structures and optimization of optical path in each compensation structure. This newly developed compensation film dramatically increased the off‐axis contrast ratio up to 300:1 by the minimization of off‐axis black light leakage and realized halo‐free display for HDR display.

CH4emission in the Arctic has large uncertainty due to the lack of mechanistic understanding of the processes. CH4oxidation in Arctic soil plays a critical role in the process, whereby removal of up to 90% of CH4produced in soils by methanotrophs can occur before it reaches the atmosphere. Previous studies have reported on the importance of rising temperatures in CH4oxidation, but because the Arctic is typically an N-limited system, fewer studies on the effects of inorganic nitrogen (N) have been reported. However, climate change and an increase of available N caused by anthropogenic activities have recently been reported, which may cause a drastic change in CH4oxidation in Arctic soils. In this study, we demonstrate that excessive levels of available N in soil cause an increase in net CH4emissions via the reduction of CH4oxidation in surface soil in the Arctic tundra. In vitro experiments suggested that N in the form of NO3–is responsible for the decrease in CH4oxidation via influencing soil bacterial and methanotrophic communities. The findings of our meta-analysis suggest that CH4oxidation in the boreal biome is more susceptible to the addition of N than in other biomes. We provide evidence that CH4emissions in Arctic tundra can be enhanced by an increase of available N, with profound implications for modeling CH4dynamics in Arctic regions.

This study explored the possibility of recycling aluminum waste scrap, an industrial byproduct resulting from the increasing production of capacitors, a vital component in the modern electronics industry, as a reinforcement material for buildings without the need for re-melting and forming process. To achieve this, an aluminum alloy perforated sheet (ALS) was developed that preserves the form of aluminum scrap and is coated with copper. ALS has the potential to be used as a reinforcing and electromagnetic wave-shielding material for building structures while suppressing the increase in self-weight. Therefore, in this study, ALS was reinforced in a highly homogeneous mortar and experimentally evaluated to determine whether it could improve the mechanical properties and electromagnetic shielding performance of the structures. Static compressive, tensile, and flexural strength tests were conducted to investigate the mechanical properties of the specimens reinforced with ALS, and electromagnetic shielding measurements were performed through waveguide tests. Among them, the tensile performance of the ALS-reinforced specimens increased to 229% in strain with a strength increase of up to 2.6 times, and the electromagnetic shielding effect was improved by 3.6 times. These results show that ALS can improve the mechanical properties and electromagnetic shielding performance of mortar specimens. In addition, based on the experimental results, this study evaluates the possibility of using ALS as a reinforcing material and discusses its applications in building systems.

The X-ray Free Electron Laser of Pohang Accelerator Laboratory (PAL-XFEL) was opened for the user in 2017. PAL-XFEL was the third XFEL facility in the world and well known for the small timing jitter of FEL radiation. This success was possible because of the significant achievements in the accelerator technology in PAL-XFEL. They are not limited to a small part of the accelerator but cover from the injector for the electron beam generation to the undulator line for FEL radiation. In this review, we describe the details of newly developed devices that contributed to the successful construction of PAL-XFEL.

AbstractThis study proposes a method for examining storage function of intercepting sewers, following sewerage rehabilitation works to convert combined-type to separate-type systems. The selected case study sewage treatment area recently completed a large-scale rehabilitation work; the area incorporates six sub-areas (SAs) and one wastewater treatment plant (WWTP), the latter having treatment capacity of 11,000 m3/d. Sewage flow generated in dry weather was domestic sewage flow only. Wet weather wastewaters consist of the dry weather sewage flow, in addition to rainfall-derived infiltration/inflow. In order to calculate wet weather wastewater flows of the six SAs, an advanced regression model was used. This was calibrated and verified using long-term monitoring flow data of 816 and 204 h, respectively; the model was then used to predict wastewater flows for 168 h. Hydraulic simulations of intercepting sewers were conducted using a conventional pipe hydrodynamic model (i.e. Saint-Venant equations). By assuming different inflow conditions to the WWTP (multiples of daily peak flows, Qd), storage function tests were conducted, based on water balance calculations between sewage flows generated from the six SAs and inflow measured at the WWTP. The existing intercepting sewer of the case study area appears to have 70, 11, and 3 h flow storage functions, for inflow controls of 1.5Qd, 2Qd, and 2.5Qd, respectively. Under 3Qdinflow conditions, almost all wastewater flowed to the WWTP. The storage function is thus expected to be effective for wet weather operation of the WWTP. Such storage function would also be achievable in other areas conducting large-scale rehabilitation works. The method proposed in this study will be useful for decision-making concerning the removal of existing intercepting sewers.

This study proposes a method for examining storage function of intercepting sewers, following sewerage rehabilitation works to convert combined-type to separate-type systems. The selected case study sewage treatment area recently completed a large-scale rehabilitation work; the area incorporates six sub-areas (SAs) and one wastewater treatment plant (WWTP), the latter having treatment capacity of 11,000 m3/d. Sewage flow generated in dry weather was domestic sewage flow only. Wet weather wastewaters consist of the dry weather sewage flow, in addition to rainfall-derived infiltration/inflow. In order to calculate wet weather wastewater flows of the six SAs, an advanced regression model was used. This was calibrated and verified using long-term monitoring flow data of 816 and 204 h, respectively; the model was then used to predict wastewater flows for 168 h. Hydraulic simulations of intercepting sewers were conducted using a conventional pipe hydrodynamic model (i.e. Saint-Venant equations). By assuming different inflow conditions to the WWTP (multiples of daily peak flows, Qd), storage function tests were conducted, based on water balance calculations between sewage flows generated from the six SAs and inflow measured at the WWTP. The existing intercepting sewer of the case study area appears to have 70, 11, and 3 h flow storage functions, for inflow controls of 1.5Qd, 2Qd, and 2.5Qd, respectively. Under 3Qdinflow conditions, almost all wastewater flowed to the WWTP. The storage function is thus expected to be effective for wet weather operation of the WWTP. Such storage function would also be achievable in other areas conducting large-scale rehabilitation works. The method proposed in this study will be useful for decision-making concerning the removal of existing intercepting sewers.

We describe two novel blue emission materials based on a new type of dual core concept. 1-Phenyl-6-(10-phenyl-anthracen-9-yl)-pyrene (Ph-AP-Ph) and 1-[1,1′;3′,1′′]terphenyl-5′-yl-6-(10-[1,1′;3′,1′′]terphenyl-5′-yl-anthracen-9-yl)-pyrene (TP-AP-TP) were synthesized through boronylation and Suzuki coupling reactions. The Tgvalues of Ph-AP-Ph and TP-AP-TP were 228 °C and 243 °C, respectively, compared to values of 135 °C and 139 °C for the single core materials 9-(3′,5′-diphenylphenyl)-10-(3′′′,5′′′-diphenylbiphenyl-4′′-yl)anthracene (MAM) and 1,6-bis-[1,1′;3′,1′′]terphenyl-5′-yl-pyrene (TP-P-TP). One of the dual core derivatives, TP-AP-TP, exhibited an ELmaxvalue of 456 nm and a high luminance EQE of 7.51% when used in an EL device. The dual core chromophore materials had narrower PL and EL spectra and better thermal properties than the single core chromophore materials. A device based on TP-AP-TP showed twice the lifetime of a device based on the commercialized material, 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN).

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Eine gezielte Genstummschaltung in Krebszellengelang mit magnetischen EisenoxidNanopartikeln MEIO, an denen ein Fluoreszenzfarbstoff, siRNA sowie ein RGDPeptid zur Erkennung von Krebszellen angebracht waren siehe Bild. Die verschiedenen funktionellen Einheiten ermöglichen eine kombinierte makroskopische Kernspin und mikroskopische FluoreszenzTomographie der Zielzellen. Dieses System könnte sich für die parallele diagnostische und therapeutische Anwendung eignen.

Cancercelltargeted gene silencingwas observed with a magneticnanoparticle platform MEIO, magnetismengineered iron oxide on which a fluorescent dye, siRNA, and a RGDpeptide targeting moiety were attached see picture. The different functionalities enable the macroscopic magnetic resonance and microscopic fluorescence imaging of target cells. This system may be suitable for concurrent diagnostic and therapeutic applications.

Synthetic magnetic nanoparticles MNPs are emerging as versatile probes in biomedical applications, especially in the area of magnetic resonance imaging MRI. Their size, which is comparable to biological functional units, and their unique magnetic properties allow their utilization as molecular imaging probes. Herein, we present an overview of recent breakthroughs in the development of new synthetic MNP probes with which the sensitive and targetspecific observation of biological events at the molecular and cellular levels is possible.

Synthetische magnetische Nanopartikel MNP werden in der Biomedizin immer häufiger als Sonden eingesetzt. Dies gilt besonders für die Anwendung in der Kernspintomographie Magnetic Resonance Imaging, MRI. Diese Nanopartikel sind von ähnlicher Größe wie biologische Funktionseinheiten. Deshalb und wegen ihrer einzigartigen magnetischen Eigenschaften eignen sie sich zur molekularen Bildgebung. Dieser Aufsatz gibt einen Überblick zu neuartigen MNPSonden, mit denen biologische Ereignisse auf molekularer und zellulärer Ebene empfindlich und spezifisch nachgewiesen werden können.

In this study, green and blue perovskite light-emitting diodes (PeLEDs) were systematically investigated by using various organic spacers of different molecular lengths to control the number of dimensions of the PeLED material. The primary perovskite used was CsPbBr3, and the organic spacers tested were aniline hydrobromide (AnBr), benzylamine hydrobromide (BABr), phenylethylamine hydrobromide (PEABr), phenylpropylamine hydrobromide (PPABr), and phenylbutylamine hydrobromide (PBABr). By specifically testing different amounts of each spacer, green to blue PeLEDs were prepared, and were analyzed using XRD and SEM. The best optical and electrical performances were obtained with PEABr as the organic spacer. Using 0.4 moles of PEABr for one mole of CsPbBr3yielded a green electroluminescence (EL) emission with a CIE of (0.078, 0.745), maximum current efficiency of 43.9 cd/A, and EQE of 8.67%; and using 1.6 moles of PEABr per mole of CsPbBr3yielded a blue EL emission with a CIE of (0.151, 0.084), maximum current efficiency of 0.87 cd/A, and EQE of 0.39 %.

Abstract:This paper presents a modelling and simulation study of advanced semiconductor devices. Different Technology Computer Aided Design approaches and models, used in nowadays research are described here. Our discussions are based on numerous theoretical approaches starting from first principle methods and continuing with discussions based on more well stablished methods such as Drift-Diffusion, Monte Carlo and Non-Equilibrium Green’s Function formalism.