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[NiFe]-hydrogenases catalyze the reversible activation of H2using a unique NiFe(CN)2CO metal site, which is assembled by a sophisticated multiprotein machinery. The [4Fe–4S] cluster-containing HypCD complex, which possesses an ATPase activity with a hitherto unknown function, serves as the hub for the assembly of the Fe(CN)2CO subfragment. HypCD is also thought to be responsible for the subsequent transfer of the iron fragment to the apo-form of the catalytic hydrogenase subunit, but the underlying mechanism has remained unexplored. Here, we performed a thorough spectroscopic characterization of different HypCD preparations using infrared, Mössbauer, and NRVS spectroscopy, revealing molecular details of the coordination of the Fe(CN)2CO fragment. Moreover, biochemical assays in combination with spectroscopy, AlphaFold structure predictions, protein–ligand docking calculations, and crosslinking MS deciphered unexpected mechanistic aspects of the ATP requirement of HypCD, which we found to actually trigger the transfer of the Fe(CN)2CO fragment to the apo-hydrogenase.

The production of cyclic amines, which are vital to the pharmaceutical industry, relies on energy-intensive thermochemical hydrogenation. Herein, we demonstrate the electrocatalytic hydrogenation of nitrogen-containing aromatic compounds, specifically pyridine, at ambient temperature and pressure via a membrane electrode assembly with an anion-exchange membrane. We synthesized piperidine using a carbon-supported rhodium catalyst, achieving a current density of 25 mA cm–2and a current efficiency of 99% under a circular flow until 5 F mol–1. Quantitative conversion of pyridine into piperidine with 98% yield was observed after passing 9 F mol–1, corresponding to 65% of current efficiency. The reduction of Rh oxides on the catalyst surface was crucial for catalysis. The Rh(0) surface interacts moderately with piperidine, decreasing the energy required for the rate-determining desorption step. The proposed process is applicable to other nitrogen-containing aromatic compounds and could be efficiently scaled up. This method presents clear advantages over traditional high-temperature and high-pressure thermochemical catalytic processes.

Two novel pyrroloiminoquinone alkaloids, 6-chlorodamirone A and 6-bromodamirone A, have been identified for the first time from the marine sponge Latrunculiasp. (order: Poecilosclerida: family Latrunculiidae), sourced from Western Australia. Alongside these new compounds, seven previously known metabolites were also isolated. Despite being obtained in submilligram quantities, the structures of these natural products were successfully elucidated using high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. To confirm the structures of these newly discovered alkaloids, a semisynthetic approach was employed starting from the more abundant metabolite, damirone A, additionally, single crystal X-ray crystallography was used to validate our structural proposals. The semisynthetic studies suggest that the chlorinated alkaloids are likely formed through a nonenzymatic conjugate halide substitution reaction rather than an enzymatic process. This reactivity parallels that observed in related metabolites, such as the caulibugulones B and C. Furthermore, a biomimetic cascade reaction was attempted to synthesize the spirodienone moiety characteristic of the discorhabdin alkaloids, inspired by the nucleophilic substitution observed in the tricyclic damirone A system. Albeit unsuccessful, these findings provide valuable insight into the reactivity of halogenated pyrroloiminoquinones under various conditions.

Scale-up isolation of (+)-(5Z)-(8S)-(14Z)-mycothiazole (1) from Vanuatu specimens of C. mycofijiensisto semisynthesize (+)-(5Z)-(8S)-8-O-acetyl-(14Z)-mycothiazole (2) revealed a new diastereomer, (−)-(5E)-(8R)-(14Z)-mycothiazole (4). The structure of 4was determined using HRMS, NMR, and comparing optical rotation to (−)-(5Z)-(8R)-(14Z)-mycothiazole (3) and 2. The maximum tolerated dose of 2in mice was 0.1 mg/kg. The IC50of 4in PANC-1 and HepG2 cancer cell lines was 111.6 and 115.0 nM. Evaluation of 4in C. elegansshowed similar oxygen consumption compared to 1–2, and all compounds significantly increased the lifespan. The Zorientation at Δ5,6is crucial for picomolar cytotoxicity but not for mitochondrial inhibition.

The PIWI-interacting RNA (piRNA) pathway guides the DNA methylation of young, active transposons during germline development in male mice1. piRNAs tether the PIWI protein MIWI2 (PIWIL4) to the nascent transposon transcript, resulting in DNA methylation through SPOCD1 (refs. 2–5). Transposon methylation requires great precision: every copy needs to be methylated but off-target methylation must be avoided. However, the underlying mechanisms that ensure this precision remain unknown. Here, we show that SPOCD1 interacts directly with SPIN1 (SPINDLIN1), a chromatin reader that primarily binds to H3K4me3-K9me3 (ref. 6). The prevailing assumption is that all the molecular events required for piRNA-directed DNA methylation occur after the engagement of MIWI2. We find that SPIN1 expression precedes that of both SPOCD1 and MIWI2. Furthermore, we demonstrate that young LINE1 copies, but not old ones, are marked by H3K4me3, H3K9me3 and SPIN1 before the initiation of piRNA-directed DNA methylation. We generated a Spocd1separation-of-function allele in the mouse that encodes a SPOCD1 variant that no longer interacts with SPIN1. We found that the interaction between SPOCD1 and SPIN1 is essential for spermatogenesis and piRNA-directed DNA methylation of young LINE1 elements. We propose that piRNA-directed LINE1 DNA methylation requires a developmentally timed two-factor authentication process. The first authentication is the recruitment of SPIN1–SPOCD1 to the young LINE1 promoter, and the second is MIWI2 engagement with the nascent transcript. In summary, independent authentication events underpin the precision of piRNA-directed LINE1 DNA methylation.

The rapid advancement in artificial intelligence and natural language processing has led to the development of large-scale datasets aimed at benchmarking the performance of machine learning models. Herein, we introduce “RetChemQA”, a comprehensive benchmark dataset designed to evaluate the capabilities of such models in the domain of reticular chemistry. This dataset includes both single-hop and multi-hop question-answer pairs, encompassing approximately 45,000 question and answers (Q&As) for each type. The questions have been extracted from an extensive corpus of literature containing about 2,530 research papers from publishers including NAS, ACS, RSC, Elsevier, and Nature Publishing Group, among others. The dataset has been generated using OpenAI’s GPT-4 Turbo, a cutting-edge model known for its exceptional language understanding and generation capabilities. In addition to the Q&A dataset, we also release a dataset of synthesis conditions extracted from the corpus of literature used in this study. The aim of RetChemQA is to provide a robust platform for the development and evaluation of advanced machine learning algorithms, particularly for the reticular chemistry community. The dataset is structured to reflect the complexities and nuances of real-world scientific discourse, thereby enabling nuanced performance assessments across a variety of tasks.

This article proposes a dynamic-tracking damping controller (DTDC) and designs an implementation scheme to alleviate the subsynchronous control interactions in series-compensated networks integrated with doubly-fed induction generator (DFIG) based wind farms. The DTDC can track subsynchronous oscillatory current components under various operating conditions, providing high damping performance for DFIG wind turbines at a broader range of subsynchronous frequencies. This is accomplished by designing an extra extended state observer based compensated loop for the rotor-side converter of DFIG, which enables the extraction and compensation of oscillatory current components at the subsynchronous frequencies. In addition, the implementation scheme for the damping controller is designed based on the dissipated energy criterion, which can identify the weak damping wind farm and determine the number of wind turbines required to be installed. The proposed DTDC's effectiveness and implementation scheme are validated using the modified IEEE first benchmark model and a wind farm model in North China, respectively. The control hardware-in-loop experiments results demonstrate that the DTDC outperforms traditional approaches with superior damping and robustness under varying wind speeds, compensation levels, and the number of online wind turbines.

A persistent challenge in brewing is the efficient utilization of hop bitter acids, with about 50% of these compounds precipitating with trub during wort boiling. This study aims to uncover the correlation between the barley cultivar proteome and hop bitter acid utilization during wort boiling. Therefore, comparative experiments were conducted using two cultivars, Liga and Solist, with varying proteomes to identify specific proteins’ role in hop bitter acids precipitation. High-performance liquid chromatography (HPLC) was used to measure hop bitter acid content, while liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify and identify proteins. The 107 protein groups, particularly enzymes linked to barley metabolic defense mechanisms, exhibited significant differences between the two cultivars. Results revealed significantly lower α- and iso-α-acid content in wort produced from the barley cultivar Liga. This study highlights the critical role of the barley proteome in optimizing process efficiency by enhancing hop utilization through barley cultivar selection.

The compound Na2B6Si2was synthesized under high-pressure, high-temperature conditions at pressures ranging from 6 to 9.5 GPa and temperatures from 1070 to 1270 K before quenching to room temperature followed by slow decompression. The crystal structure was determined from microcrystals using precession-assisted electron diffraction tomography, validated by dynamical refinement and full-profile refinements using optimized coordinates from quantum chemical calculations (space group R3̅m, Pearson symbol hR30, a= 5.0735(1) Å and c= 16.0004(7) Å). The atomic arrangement consists of a unique framework formed by electron-precise octahedral closo (B6)2–clusters connected via ethane-like (Si2)0dumbbells. The Na+cations occupy cavities in the hierarchical variation of a Heusler-type framework. The balance (Na+)2([B6]2–)(Si0)2reveals an electron precise Zintl-Wade phase, which is in line with electronic band structure calculations predicting semiconducting behavior.

Haiku is the world's shortest form of poetry, describing nature and ordinary everyday life. Previous studies and quotes from professional haiku poets suggest that haiku can foster self‐transcendent emotions, such as gratitude and awe. This study compares how those who did and did not create at least one haiku in the past month experience self‐transcendent emotions. A total of 192 haiku writers and 177 non‐writers responded to scales related to self‐transcendent emotions, such as gratitude for serenity, gratitude trait, and trait awe. The results of the Bayesian implementation of Generalized Linear Mixed models revealed that haiku writing increased the frequency of gratitude for serenity and awe, rather than general gratitude. These effects persisted even after controlling for interest in art and educational level, indicating that haiku writing has unique characteristics, including encouragement of attention to nature and a different perspective on daily life. Even in the absence of special events, a change in perspective toward everyday life occurs through creating haiku, and people appreciate and feel awe toward ordinary, everyday things. These novel findings contribute to the study of creativity and emotion.

To date, there are several measurement methods for evaluating human kinematics based on inertial sensors or vision systems. However, a comprehensive comparison has not been undertaken to determine which of these systems offers the most appropriate accuracy for clinical or sports evaluations. This study conducted a comparative analysis of different motion measurement systems: optoelectronic system (OS), inertial measurement units (IMUs), and vision-based methods, including deep neural network (DNN) and non-DNN approaches. Ten healthy subjects were involved, performing walking (W.) and running (R.) tests at various speeds (3.5, 5.0, and 7.0 km/h). The measurement of human kinematics was conducted by taking video images via two RGB cameras, together with an IMU-based system and an OS as the gold standard. Comparative analysis was conducted on a set of measurement methods, including IMU, a method based on blob analysis (BA), and DNN algorithms: Alphapose (AP), TC former (TC), RTMPose (RTM), and MediaPipe (MP). Data analysis involved triangulation and measurement of lower limb joint angles. Results showed that vision systems do not allow ankle joint measurement, and IMUs outperformed other methods in terms of RMSE and absolute error of range of motion ( $\varepsilon _{\text {ROM}}\text {)}$ . RTM and MP exhibited results similar to IMUs, especially for the hip and knee joints, with the minimum absolute error reporting values of ( $3.1^{\circ }~\pm ~1.8^{\circ }\text {)}$ and ( $3.5^{\circ }~\pm ~1.9^{\circ }\text {)}$ for the hip joint and ( $4.0^{\circ }~\pm ~3.7^{\circ }\text {)}$ and ( $4.8^{\circ }~\pm ~4.3^{\circ }\text {)}$ for the knee joint, respectively.

People living in coastal areas have the advantage of accessing a high level of ecosystem services, but are also exposed to the dangers inherent in living by the sea in an area prone to natural disasters. To achieve sustainable utilization of the high ecosystem services of coastal areas, establishment of an effective marine policy based on regional characteristics of human–nature interactions is essential. We compared the structure of perceived satisfaction for five components of human well-being (‘Security’, ‘Basic material for a good life’, ‘Good social relations’, ‘Health’, and ‘Freedom of choice and action’) derived from coastal ecosystem services among three sites in Japan (Wakasa, Sanriku, and Shima) that share the same natural and social backgrounds: highly dependent on fisheries industry, located in the same climate regime (temperate zone), and have similar topographical features (ria coast). Structural equation modeling using the results from questionnaire surveys showed that the three sites shared a common basic structure of the interactions among the five components of human well-being. However, the intensity of interactions among components differed among the three sites. Questionnaire surveys on anxiety about natural disasters and future access to marine ecosystem services were simultaneously conducted at the three sites. The site-specific anxieties were responsible for the difference in the interactions among the five components of human well-being. We propose a method that quantitatively evaluates both positive (satisfaction) and negative (anxiety) aspects of respondents’ subjective assessment as a useful tool for understanding the diversity of human–nature interactions caused by the region-specific natural and social backgrounds of coastal areas.

Hybrid battery cells that combine a garnet-type Li7La3Zr2O12(LLZO) solid electrolyte with other solid, polymer or liquid electrolytes are increasingly investigated. In such cells with layered electrolytes, ensuring a low-resistive heteroionic interface between neighboring electrolytes is crucial for preventing major additional overpotentials during operation. Electrochemical impedance spectroscopy is frequently used to extract such parameters, usually on multilayer symmetrical model cells that contain the different electrolytes stacked in series. Unfortunately, the impedance contributions of the heteroionic interfaces often overlap with those of the electrolyte|electrode interfaces, necessitating the use of sophisticated four-point cells that probe the electrochemical potential away from the polarization source. In this work, an alternative solution to this problem is demonstrated by taking advantage of the inherent fast charge transfer kinetics of LLZO with its parent metal electrode. The “resistance-free” nature of a reversible Li|LLZO interface enables a precise evaluation of the heteroionic interface impedance in symmetric two-point cells of the type Li|LLZO|electrolyte|LLZO|Li with negligible electrode contribution. This is exemplified for symmetric multilayer cells containing tantalum-doped LLZO and a poly(ethylene oxide) (PEO)-based dry polymer electrolyte. Validation and comparison of impedance data with results from symmetric four-point cells and two-point cells with ion-blocking electrodes demonstrate the advantage of the proposed method. Overall, this study presents a simple and reliable method for studying heteroionic interface impedances in LLZO-containing multilayer cells.

Fungi are among the most diverse and ecologically important kingdoms in life. However, the distributional ranges of fungi remain largely unknown as do the ecological mechanisms that shape their distributions1,2. To provide an integrated view of the spatial and seasonal dynamics of fungi, we implemented a globally distributed standardized aerial sampling of fungal spores3. The vast majority of operational taxonomic units were detected within only one climatic zone, and the spatiotemporal patterns of species richness and community composition were mostly explained by annual mean air temperature. Tropical regions hosted the highest fungal diversity except for lichenized, ericoid mycorrhizal and ectomycorrhizal fungi, which reached their peak diversity in temperate regions. The sensitivity in climatic responses was associated with phylogenetic relatedness, suggesting that large-scale distributions of some fungal groups are partially constrained by their ancestral niche. There was a strong phylogenetic signal in seasonal sensitivity, suggesting that some groups of fungi have retained their ancestral trait of sporulating for only a short period. Overall, our results show that the hyperdiverse kingdom of fungi follows globally highly predictable spatial and temporal dynamics, with seasonality in both species richness and community composition increasing with latitude. Our study reports patterns resembling those described for other major groups of organisms, thus making a major contribution to the long-standing debate on whether organisms with a microbial lifestyle follow the global biodiversity paradigms known for macroorganisms4,5.

Characterization of defects in large 3D printed metals is critical but challenging. This study reports on the X-ray micro-computed tomography (micro-CT) examination of porosities in large-volume 3D-printed and heat-treated titanium (Ti–6Al–4V) alloys, together with their tensile properties and failure mechanisms. Titanium alloy powders were analyzed using scanning electron microscopy (SEM). Laser powder bed fusion (L-PBF) was used to print titanium alloy specimens vertically and horizontally, followed by stress-relieved heat treatment. Micro-CT imaging was performed on printed specimens of 10 × 20 mm3(diameter × length) to determine their porosities, pore locations and size distributions using an industrial micro-CT system and relevant imaging software. Tensile testing of the processed specimens was conducted to determine their mechanical properties. Optical microscopy and SEM were used to examine the tension-induced failure mechanisms. The results show that porosities, pore sizes and locations were influenced by the build direction, resulting in different mechanical properties. Horizontal printing achieved higher tensile modulus, strength, ductility, resilience and toughness than vertical printing. Heat treatment did not change porosities in horizontally built specimens, but slightly reduced porosities for vertically built ones by 10%. This led to most mechanical properties nearly unchanged for the horizontally printed specimens but remarkably increased yield and tensile strength, and resilience, for the vertically printed ones. All tension-induced fractured surfaces contained pores, possible indicators of failure origins, which should be diminished in advanced processes for higher mechanical reliability.

Increased hair in Arabidopsisroots during phosphorus deficiency is an important adaptation mechanism. The CAPRICE(CPC) gene, along with its six homologs, plays a pivotal role in root hair formation. Our previous study indicated upregulated expression of ENHANCER OF TRY AND CPC1(ETC1) and ENHANCER OF TRY AND CPC3(ETC3) homologous genes in response to phosphorus deficiency. ETC1 translocates from the root sub-epidermis to epidermal cells, thereby increasing the number of root hairs. In this study, we specifically focused on ETC3 to explore its function in this process. Our results showed that etc1, etc3, and etc1 etc3mutants did not induce as much root hairs in response to phosphorus deficiency as the wild type. The upregulation of ETC1and ETC3in response to phosphorus deficiency was restricted to the roots, with no such response observed in leaves. Furthermore, examination of ETC3:GFP protein localization revealed that ETC3 expression was induced in the internal root tissues under phosphorus deficiency, without migrating to epidermal cells as observed for ETC1. This finding suggests that ETC3 may indirectly contribute to root hair formation through a different mechanism. Therefore, elucidating the complex process that governs root hair increase in phosphorus-deficient plants can lead to future advances in plant breeding and nutrient stress adaptation.

The primary issue with joining an immiscible magnesium/iron system is the lack of a bonding medium. This research used an aluminium (Al) additive as a bonding medium to facilitate the formation of an interface layer. Immiscible AZ31 magnesium alloy and SPHC low-carbon steel were successfully joined by employing aluminium (Al) powder as an additive in the gap between them with friction stir welding (FSW). The extensive interfacial microstructural analyses confirmed that the aluminium-rich Fe2Al5intermetallic compound (IMC) formed with a range of 20–25 nm in thickness at the interface between magnesium and iron resulted from the metallurgical reaction between the Al powder additive and base SPHC steel. This IMC phase served as a transitional layer, facilitating the metallurgical bonding between Magnesium and Iron. The tensile strength of the joint was significantly improved by 43%, from 126 MPa without the additive to 180 MPa using the aluminium additive. The formation of the following well-matched interface lattice sites between Fe and Fe2Al5region was identified: (002)Fe2Al5//(110)Fe, [110]Fe2Al5//[1‾13]Fe. The intermetallic Fe2Al5was composed of nanocrystalline and amorphous interface layers. Furthermore, the fracture of the joint occurred at the interface, indicating a brittle mode of fracture behaviour.

There are few studies examining the wellbeing of Australian school-based psychologists/counsellors (SPCs) despite the research indicating there are unique stressors associated with the role. The purpose of this study was to measure the stress perceived by working Australian SPCs. Data were collected via an online survey within which the Perceived Stress Scale – 10 item version (PSS-10) was embedded. Mean global stress for 162 participants was calculated then compared with the general population and a previous cohort of Australian SPCs. Four variables of influence were also statistically analysed: school level, years of experience, amount of time participating in supervision and alignment with two differing professional identity statements – ‘I see myself as an educator with a counselling/psychology specialisation’ or ‘as a psychologist/counsellor who works in an education setting’. Moderate – high frequency of stress, in excess of the general population and stress levels reported previously, was found. No significant relationships were found between stress and school level, years of experience or professional identity. A negative relationship was found between stress and the amount of supervision received. The level of stress experienced by Australian SPCs warrants that policies and practices monitor and protect Australian SPC wellbeing.

Chimpanzees (Pan troglodytes) with teeth severely damaged by dental caries and/or periodontal disease are often managed with medication and/or tooth extraction. A common endodontic treatment for severely decayed teeth in a 26-year-old female chimpanzee is reported. The left maxillary central incisor tooth had lost its crown, probably due to trauma that was not recent, and it had a fistula most likely due to chronic apical periodontitis. The diagnosis was confirmed radiographically before treatment. To treat the infected root canal, endodontic treatment used in humans was adapted for a chimpanzee. After the treatment, the tooth was sealed using an adhesive resin composite. At 11-years post-treatment, there were no signs of recurrence of the lesion or of failure of the tooth seal. The results of this case report suggest that common endodontic treatments used in humans are also effective in chimpanzees.

In order to investigate the occurring processes during long-term dry storage of spent fuel assemblies, a joined project called SPIZWURZ, between the Karlsruhe Institute of Technology and the Gesellschaft für Anlagen-und Reaktorsicherheit (GRS), was started. Aim of the SPIZWURZ project is the determination and quantification of the influence of texture and elastic strain on diffusion and solubility of hydrogen in three different zirconium alloys used in western Europe during a long-term cooling transient (1 K/d) starting at 400 °C. The strain in the cladding of an irradiated spent fuel rod shall be measured. Models predicting the formation of radial oriented hydrides will be validated, improved, and implemented in the GRS fuel rod performance code TESPA-ROD. This paper describes the SPIZWURZ project and already obtained first results.

Kinetic studies on the photochemical quenching reaction of the tris(2,2′-bipyridyl) ruthenium(II) complex ([Ru(bpy)3]2+) in water-glycerol binary media were conducted based on the Einstein–Smoluchowski (E-S) theory. Dynamic and static quenching behaviors were analyzed by comparing results from time-resolved spectroscopy and emission spectroscopy. While the dynamic quenching reaction aligns well with the E-S theory, static quenching was observed, leading to a notable increase in the overall photoquenching reaction rate constant. Employing chromatography and infrared spectroscopy, we correlated the microscopic molecular structure of the binary solvent system and the solvation environment around the emitters with the reaction mechanism. This correlation was found to correspond to ion pair formation and the confinement effect of the emitter, respectively.

This article presents a new multiplexed-stack converter (MSC) for high-voltage direct-current (HVDC) power conversion. The MSC reduces the number of stacks of submodules (SMs) needed for three-phase alternating-current (AC) systems from six, as in conventional modular multilevel converters (MMCs), to four, which can substantially decrease the size of converter stations. The MSC comprises two full-bridge SM (FBSM)-based Outer stacks, two half-bridge SM (HBSM)-based Inner SM stacks, and director-switch (DS) valves to generate sinusoidal three-phase AC voltages. The MSC offers several benefits over existing converters: it can handle and block DC faults due to its FBSM-based Outer stacks, it can attain high efficiency due to its HBSM-based Inner stacks, and it can ease valve design due to fundamental-frequency and zero-voltage-switching (ZVS) operation of its DSs. A sweet-spot operating voltage is derived where the Outer and Inner stack energies are naturally balanced without the need of DC pole capacitors (PCs). For deviations from the sweet-spot voltage, DC-side PCs enable energy balancing for the stacks. This article presents HVDC-scale simulations and reduced-scale hardware experiments that confirm the MSC’s performance in real and reactive power conversion. This article also contrasts the MSC with other state-of-the-art converters, indicating its competitive efficiency and compactness.

In this paper, a novel dual-arm modular multilevel converter (DAC) with inherent DC-fault-blocking capability is proposed that needs only two stacks of submodules (SMs), as well as director switches (DSs), for multilevel AC/DC conversion. Compared to the state-of-the-art modular multilevel converter (MMC) technologies with six SM-based arms, the DAC's dual multiplexed converter arm structure, combined with needing approximately 75% less capacitive energy storage than the MMC, facilitate a smaller converter station footprint. This paper presents the operating principle of the DAC and benchmarks it against other voltage source converter technologies based on converter functionalities, component count, capacitive energy storage requirements, and semiconductor losses for high voltage direct current transmission (HVDC) application. For a wider output voltage range, overlap operation is proposed to enable circulating currents to balance the SM capacitors’ energy cycle-to-cycle. A 600 kV HVDC system simulation study is presented that demonstrates the DAC's ability to (1) transmit power bidirectionally under nominal conditions, and (2) extinguish fault currents during DC-side short-circuit fault. A ${200}\; {{{V}}}_{\text{DC}}$ scaled-down converter hardware implementation further verifies the DAC's operating principle.

In the development of linear quadratic regulator (LQR) algorithms, the Riccati equation approach offers two important characteristics —it is recursive and readily meets the existence condition. However, these attributes are applicable only to transformed singular systems, and the efficiency of the regulator may be undermined if constraints are violated in nonsingular versions. To address this gap, we introduce a direct approach to the LQR problem for linear singular systems, avoiding the need for any transformations and eliminating the need for regularity assumptions. To achieve this goal, we begin by formulating a quadratic cost function to derive the LQR algorithm through a penalized and weighted regression framework and then connect it to a constrained minimization problem using the Bellman's criterion. Then, we employ a dynamic programming strategy in a backward approach within a finite horizon to develop an LQR algorithm for the original system. To accomplish this, we address the stability and convergence analysis under the reachability and observability assumptions of a hypothetical system constructed by the pencil of augmented matrices and connected using the Hamiltonian diagonalization technique.

Graphical abstract:

‘Anode-free’ or, more fittingly, metal reservoir-free cells could drastically improve current solid-state battery technology by achieving higher energy density, improving safety and simplifying manufacturing. Various strategies have been reported so far to control the morphology of electrodeposited alkali metal films to be homogeneous and dense, but until now, the microstructure of electrodeposited alkali metal is unknown, and a suitable characterization route is yet to be identified. Here we establish a reproducible protocol for characterizing the size and orientation of metal grains in differently processed lithium and sodium samples by a combination of focused ion beam and electron backscatter diffraction. Electrodeposited films at Cu|Li6.5Ta0.5La3Zr1.5O12, steel|Li6PS5Cl and Al|Na3.4Zr2Si2.4P0.6O12interfaces were characterized. The analyses show large grain sizes (>100 µm) within these films and a preferential orientation of grain boundaries. Furthermore, metal growth and dissolution were investigated using in situ electron backscatter diffraction, showing a dynamic grain coarsening during electrodeposition and pore formation within grains during dissolution. Our methodology and results deepen the research field for the improvement of solid-state battery performance through a characterization of the alkali metal microstructure.

Abstract.This study examined the factor structure and reliability of the Psychobiosocial States (PBS-S) scale in the assessment of situational performance-related experiences. We administered the scale to 483 Finnish athletes before a practice session to assess the intensity and perceived impact of their performance-related feeling states. The hypothesized two-factor structure indicating functional effects (10 items) and dysfunctional effects (10 items) toward performance was examined via exploratory structural equation modeling (ESEM) and confirmatory factor analysis (CFA). Regarding the intensity and perceived impact dimensions of reported states, ESEM and CFA showed a good fit for a two-factor solution of a 14-item PBS-S scale (seven functional and seven dysfunctional items). For both intensity and impact ratings, core state functional modalities were bodily, cognitive, and volitional, while core state dysfunctional modalities were volitional, operational, and anxiety. Findings support the use of a 14-item PBS-S scale to measure a range of preperformance states.

The state-of-the-art saturable phase-domain (PD) and voltage-behind-reactance (VBR) synchronous machine models have been recently considered in the literature as reliable and accurate alternatives to the traditional qd0 models. However, due to the rotor-position- and saturation-dependent interfacing circuit, implementing these models in electromagnetic transient (EMT) simulators has been challenging due to the need to refactorize the machine-network conductance matrix at each time step during simulation. This article presents two new VBR-based synchronous machine models with main flux saturation that yield constant interfacing conductance matrix in EMTP-type solution. Case studies in PSCAD/EMTDC verify that the proposed models demonstrate numerical accuracy similar to the state-of-the-art models, while achieving significant computational gains in multimachine systems.

BackgroundGraves’ orbitopathy (GO) is subject to epidemiological and care-related changes. Aim of the survey was to identify trends in presentation of GO to the European Group On Graves’ Orbitopathy (EUGOGO) tertiary referral centres and initial management over time.MethodsProspective observational multicentre study. All new referrals with diagnosis of GO within September–December 2019 were included. Clinical and demographic characteristics, referral timelines and initial therapeutic decisions were recorded. Data were compared with a similar EUGOGO survey performed in 2012.ResultsBesides age (mean age: 50.5±13 years vs 47.7±14 years; p 0.007), demographic characteristics of 432 patients studied in 2019 were similar to those in 2012. In 2019, there was a decrease of severe cases (9.8% vs 14.9; p<0.001), but no significant change in proportion of active cases (41.3% vs 36.6%; p 0.217). After first diagnosis of GO, median referral time to an EUGOGO tertiary centre was shorter (2 (0–350) vs 6 (0–552) months; p<0.001) in 2019. At the time of first visit, more patients were already on antithyroid medications (80.2% vs 45.0%; p<0.001) or selenium (22.3% vs 3.0%; p<0.001). In 2019, the initial management plans for GO were similar to 2012, except for lid surgery (2.4% vs 13.9%; p<0.001) and prescription of selenium (28.5% vs 21.0%; p 0.027).ConclusionGO patients are referred to tertiary EUGOGO centres in a less severe stage of the disease than before. We speculate that this might be linked to a broader awareness of the disease and faster and adequate delivered treatment.

Humans have the remarkable cognitive capacity to rapidly adapt to changing environments. Central to this capacity is the ability to form high-level, abstract representations that take advantage of regularities in the world to support generalization1. However, little is known about how these representations are encoded in populations of neurons, how they emerge through learning and how they relate to behaviour2,3. Here we characterized the representational geometry of populations of neurons (single units) recorded in the hippocampus, amygdala, medial frontal cortex and ventral temporal cortex of neurosurgical patients performing an inferential reasoning task. We found that only the neural representations formed in the hippocampus simultaneously encode several task variables in an abstract, or disentangled, format. This representational geometry is uniquely observed after patients learn to perform inference, and consists of disentangled directly observable and discovered latent task variables. Learning to perform inference by trial and error or through verbal instructions led to the formation of hippocampal representations with similar geometric properties. The observed relation between representational format and inference behaviour suggests that abstract and disentangled representational geometries are important for complex cognition.

Microtubule (MT) filaments, composed of α/β-tubulin dimers, are fundamental to cellular architecture, function and organismal development. They are nucleated from MT organizing centers by the evolutionarily conserved γ-tubulin ring complex (γTuRC). However, the molecular mechanism of nucleation remains elusive. Here we used cryo-electron tomography to determine the structure of the native γTuRC capping the minus end of a MT in the context of enriched budding yeast spindles. In our structure, γTuRC presents a ring of γ-tubulin subunits to seed nucleation of exclusively 13-protofilament MTs, adopting an active closed conformation to function as a perfect geometric template for MT nucleation. Our cryo-electron tomography reconstruction revealed that a coiled-coil protein staples the first row of α/β-tubulin of the MT to alternating positions along the γ-tubulin ring of γTuRC. This positioning of α/β-tubulin onto γTuRC suggests a role for the coiled-coil protein in augmenting γTuRC-mediated MT nucleation. Based on our results, we describe a molecular model for budding yeast γTuRC activation and MT nucleation.

Torque ripple reduction based on harmonic current injection has been developed for PMSM drives. In such methods, torque ripple model (TRM) or speed harmonics are used for harmonic current optimization, which have several limitations. The performance of TRM based methods is limited due to the accuracy of the model itself and machine parameters, which leads to the remaining torque ripples. The speed harmonic-based methods have speed limitations, since the speed harmonics generated by the torque ripples cannot be detected at high-speed operations. In this article, the torque ripples of PMSM drives are first described based on the surrogate model, which does not require machine parameters. Based on that, the numerical solution of optimal harmonic currents is obtained offline using particle swarm optimization, considering both torque ripple reduction and loss minimization. Since the torque ripples are predicted with the machine-parameter-independent model instead of the speed harmonic measurements, the impact of the inaccuracy in machine parameters and the analytical torque ripple model are removed, and the proposed method may be effective over a broader range of speeds. The proposed method is evaluated experimentally and demonstrated to have several advantages over existing alternative methods in reducing torque ripples.

Studies of bacterial adaptation and evolution are hampered by the difficulty of measuring traits such as virulence, drug resistance, and transmissibility in large populations. In contrast, it is now feasible to obtain high-quality complete assemblies of many bacterial genomes thanks to scalable high-accuracy long-read sequencing technologies. To exploit this opportunity, we introduce a phenotype- and alignment-free method for discovering coselected and epistatically interacting genomic variation from genome assemblies covering both core and accessory parts of genomes. Our approach uses a compact colored de Bruijn graph to approximate the intragenome distances between pairs of loci for a collection of bacterial genomes to account for the impacts of linkage disequilibrium (LD). We demonstrate the versatility of our approach to efficiently identify associations between loci linked with drug resistance and adaptation to the hospital niche in the major human bacterial pathogens Streptococcus pneumoniaeand Enterococcus faecalis.

Model predictive control (MPC) has recently been considered for many permanent magnet synchronous motor (PMSM) drive applications. However, the conventional MPC presents insufficient overmodulation capability and, thus, cannot reach the six-step operation, which limits its application in the traction drive areas. This article proposes a novel MPC-based six-step operation scheme for the PMSM drive in traction applications. The prediction horizon is extended to the whole commutation period of the six-step operation, and a new average current-based objective function is introduced to determine the optimal commutation instants. To enhance the method's precision, a trapezoidal discretization method has been adopted in the long-horizon prediction. The effectiveness of the proposed method has been validated by detailed studies. The proposed method is demonstrated to have excellent current-tracking accuracy and fast dynamic response in the six-step operation, which is an advantage over the existing methods.

Electrical machines are extensively used in our everyday life. On the one hand, this can be seen in the rapid growth of generation from renewable energy sources such as wind, hydropower, tidal, etc. On the other hand, at the energy utilization and consumption end visible to most people, we are also witnessing revolutionary changes in many sectors, such as the electrification of all types of transportation, i.e., electric vehicles, industry-wide initiatives for more-electric aircraft and more-electric ships, military vehicles and defense systems, industrial automation, industrial and personal robots, medical devices and instruments, flying drones, electronic toys, and the multitude of household appliances and devices, all of which are designed and built with electric motors of various types and sizes.

There are limited resources for guidance on the transition from fellowship into a new faculty role in pediatric infectious diseases. This review aims to address this gap and provides a framework for a successful transition that is composed of four essential pillars—(1) stepping into your role, (2) finding your niche, (3) building your network, and (4) self-care—all of which are supported by strong mentorship/sponsorship and continual realignment with one’s personal mission statement. In addition to providing general principles and guidance, this review also outlines specific steps that a junior faculty member can take to expand their influence and build a successful, fulfilling career in pediatric infectious diseases.

Optimal dosing of valganciclovir (VGCV) for cytomegalovirus (CMV) prevention in pediatric solid organ transplantation recipients (SOTR) is controversial. Dosing calculated based on body surface area (BSA) and creatinine clearance is recommended but simplified body weight (BW) dosing is often prescribed. We conducted a retrospective 6-center study to compare safety and efficacy of these strategies in the first-year posttransplant There were 100 (24.2%) pediatric SOTR treated with BSA and 312 (75.7%) with BW dosing. CMV DNAemia was documented in 31.0% vs 23.4% (P= .1) at any time during the first year and breakthrough DNAemia in 16% vs 12.2% (P= .3) of pediatric SOTR receiving BSA vs BW dosing, respectively. However, neutropenia (50% vs 29.3%, P<.001), lymphopenia (51% vs 15.0%, P<.001), and acute kidney injury causing treatment modification (8.0% vs 1.8%, P<.001) were documented more frequently during prophylaxis in pediatric SOTR receiving BSA vs BW dosing. The adjusted odds ratio of VGCV-attributed toxicities comparing BSA and BW dosing was 2.3 (95% confidence interval [CI], 1.4-3.7] for neutropenia, 7.0 (95% CI, 3.9-12.4) for lymphopenia, and 4.6 (95% CI, 2.2-9.3) for premature discontinuation or dose reduction of VGCV, respectively. Results demonstrate that BW dosing is associated with significantly less toxicity without any increase in CMV DNAemia.

DNA is an anisotropic, water-attracting, and biocompatible material, an ideal building block for hydrogel. The alignment of the anisotropic DNA chains is essential to maximize hydrogel properties, which has been little explored. Here, we present a method to fabricate the anisotropic DNA hydrogel that allows precise control for the polymerization process of photoreactive cationic monomers. Scanning ultraviolet light enables the uniaxial alignment of DNA chains through the polymerization-induced diffusive mass flow using a concentration gradient. While studying anisotropic mechanical properties and orientation recovery according to the DNA chain alignment direction, we demonstrate the potential of directionally controlled DNA hydrogels as smart materials.

Purpose: This study assessed two technology systems aimed at enabling a man with intellectual disability, blindness, deafness and motor and tactile discrimination problems to make verbal requests through simple one-hand signs. Design/methodology/approach: The study was conducted according to an ABAB design. During the B (intervention) phases, the man used the two systems, which included (1) nine mini recording devices fixed on the man’s clothes or wheelchair (i.e. in positions the man touched with his sign movements) and (2) nine tags with radio frequency identification codes (fixed at approximately the same positions as the mini recording devices) and a dedicated tag reader, respectively. Making a sign (i.e. touching a recording device or reaching a tag) led to the verbalization of the request related to that sign. Findings: During baseline, the mean frequency of signs/requests made was below 2 per session, and only some of those requests were identified/satisfied. During the intervention, the mean frequency of requests made and satisfied was about 10 per session with each of the systems. Originality/value: The results, which are to be taken with caution given the preliminary nature of the study, seem to suggest that the systems can help translate simple signs into verbal requests.

In this brief, we propose a suboptimal control update for lossless storage systems that operates based on the instantaneous value of the load power and generalizes previously suggested solutions for energy management problems. The proposed control update performs under uncertain conditions and does not require statistical information about the load profile. We leverage tools from Pontryagin’s minimum principle and stochastic dynamic programming methods to derive the control strategy and then investigate its stability properties using the Lyapunov analysis. However, the analysis of this control paradigm presents significant challenges, among which the key difficulty arises due to the presence of nonlinear feedback terms. To address this challenge, we first introduce a coordinate transformation, which transforms the original problem into an equivalent stabilization problem, and then verify its stability properties using the Lyapunov function theory and LaSalle’s invariance principle. We show that the proposed control policy works for both continuous-time and stochastic load profiles, and it keeps the stored energy within the capacity bounds by following the optimal path.

Many nonlinear physical phenomena, including various power systems, can be modeled, analyzed, and controlled using the framework of port-Hamiltonian systems. Moreover, this framework can offer more advanced methods to cope with modern challenges in the energy sector. This paper presents a comprehensive and systematic survey of recent studies on the application of the port-Hamiltonian approach to power systems. Over a hundred of relevant research works are reviewed to show the vast capabilities of this approach and point out its possible gaps. The works are classified according to the type of power systems under study. The analysis of the articles shows that the vast majority of them are dedicated to controller design, a much smaller part of the works deals with the modeling and stability issues, and only a few consider the problem of optimal control. Moreover, the paper discusses current challenges and future trends in this direction.