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The synthesis of amides from amines and carboxylic acids is the most widely carried out reaction in medicinal chemistry. Yet, most amide couplings are still conducted using stoichiometric reagents, leading to significant waste; few synthetic catalysts for this transformation have been adopted industrially due to their limited scope and/or poor recyclability. The majority of catalytic approaches focus on a single activation mode, such as enhancing the electrophilicity of the carboxylic acid partner using a Lewis acid. In contrast, nature effortlessly forges and breaks amide bonds using precise arrays of Lewis/Brønsted acidic and basic functional groups. Drawing inspiration from these systems, herein we report a simple defect engineering strategy to colocalize Lewis acidic Zr sites with other catalytically active species within porous metal–organic frameworks (MOFs). Specifically, the combination of pyridine N-oxide and Zr open metal sites within the defective framework MOF-808-py-Noxproduces a heterogeneous catalyst that facilitates amide bond formation with broad functional group compatibility from amines and carboxylic acids, esters, or primary amides. Extensive density functional theory (DFT) calculations using cluster models support that the formation of a hydrogen-bonding network at the defect sites facilitates amide bond formation in this material. MOF-808-py-Noxcan be recycled at least five times without losing significant crystallinity, porosity, or catalytic activity and can be employed in continuous flow. This defect engineering strategy can be potentially generalized to produce libraries of catalytically active MOFs with different combinations of colocalized functional groups.

The survival and growth of plant pathogens on crop residues are key factors facilitating the dynamics of crop diseases. Spores (e.g., perithecia, and chlamydospores) and mycelium of pathogenic fungi overwinter on harvest residues, such as straw, and serve as initial inoculum infecting crops in the next growing season. Therefore, targeting overwintering fungi is essential to attaining effective disease control. Beneficial microorganisms offer advantages in controlling pathogens through their ability to colonize and exploit different environmental niches. In this study, we applied qPCR assays to explore the biocontrol performance of locally isolated strains of Clonostachysagainst various Fusariumpathogens. We proved that prior colonization of wheat straw by Fusariumspp. can be effectively reduced by Clonostachys rosea. We demonstrated that the efficiency of C. roseato reduce Fusariuminoculum appears to remain at a similar level for most studied strains regardless of the target pathogen and the level of colonization of substrates by pathogens. Efficient performance of local C. roseastrains identifies possible targets for future strategies to control Fusarium diseases in cereals. Our study also highlights the challenge in sequence-based determination of C. rosea,which is crucial for the efficient selection of beneficial strains for biocontrol purposes.

Phototoxicity and skin cancer are severe adverse effects of the anti-fungal drug voriconazole (VOR). These adverse effects resemble those seen in xeroderma pigmentosum, caused by defective DNA nucleotide excision repair (NER), and we show that VOR decreases NER capacity. We show that VOR treatment does not perturb the expression of NER, or other DNA damage-related genes, but that VOR localizes to heterochromatin, in complexes containing histone acetyltransferase general control of amino-acid synthesis 5-like 2. Impairment of general control of amino-acid synthesis 5-like 2 binding to histone H3 reduced acetylation of H3, restricting damage-dependent chromatin unfolding, thereby reducing NER initiation. Restoration of H3 histone acetylation using histone deacetylase inhibitors, rescued VOR-induced NER repression, thus offering a preventive therapeutic option. These findings underline the importance of DNA damage-dependent chromatin remodeling as an important prerequisite of functional DNA repair.

We conducted a study on the performance of the local hybrid exchange–correlation functional PBE0r for a set of 95 experimentally characterized iron spin-crossover (SCO) complexes [Vennelakanti, V.; J. Chem. Phys.2023, 159, 024120]. The PBE0r functional is a variant of PBE0 where the exchange correction is restricted to on-site terms formulated on the basis of local orbitals. We determine the free parameters of the PBE0r functional against the experimental data and other hybrid functionals. With a Hartree–Fock (HF) exchange factor of 4%, the PBE0r functional accurately reproduces the electronic and free-energy trends predicted in prior DFT studies for these 95 complexes by using the B3LYP functional. Larger values of HF exchange stabilize high-spin states. The PBE0r-predicted bond lengths tend to exceed the experimental bond lengths, although bond lengths are less sensitive to HF exchange than in global hybrids. The predicted SCO transition temperatures T1/2from PBE0r correlate moderately with the experimental transition temperatures, showing a slight improvement compared to the previous modB3LYP-predicted T1/2. This study suggests that the PBE0r functional is computationally cost-effective and offers the possibility of simulating larger complexes with accuracy comparable to global hybrid functionals, provided the HF-exchange parameter is carefully optimized.

Aggregation-induced emission luminogens (AIEgens) that respond to mechanical force are increasingly used as force probes, memory devices, and advanced security systems. Most of the known mechanisms to modulate mechanoresponsive AIEgens have been based on changes in aggregation states, involving only physical alterations. Instances that employ covalent bond cleavage are still rare. We have developed a novel mechanochemical uncaging strategy to unveil AIEgens with diverse emission characteristics using engineered norborn-2-en-7-one (NEO) mechanophores. These NEOmechanophores were covalently integrated into polymer molecules and activated in both the solution and solid states. This activation resulted in highly tunable fluorescence upon immobilization through solidification or aggregation, producing blue, green, yellow, and orange-red emissions. By designing the caged and uncaged forms as donor–acceptor pairs for Förster resonance energy transfer (FRET), we achieved multicolor mechanofluorescence, effectively broadening the color spectrum to include white emission. Additionally, we computationally explored the electronic structures of activated NEOs, providing insights into the observed regiochemical effects of the substituents. This understanding, together with the novel luminogenic characteristics of the caged and activated species, provides a highly tunable reporter that traces progress with continuous color evolution. This advancement paves the way for future applications of mechanoresponsive materials in areas like damage detection and bioimaging.

Metal–organic cages form well-defined microenvironments that can enhance the catalytic proficiency of encapsulated transition metal complexes (TMCs). We introduce a screening protocol to efficiently identify TMCs that are promising candidates for encapsulation in the Ga4L612–nanocage. We obtain TMCs from the Cambridge Structural Database with geometric and electronic characteristics amenable to encapsulation and mine the text of associated manuscripts to curate TMCs with documented catalytic functionality. By docking candidate TMCs inside the nanocage cavity and carrying out electronic structure calculations, we identify a subset of successfully optimized candidates (TMC-34) and observe that encapsulated guests occupy an average of 60% of the cavity volume, in line with previous observations. Notably, some guests occupy as much as 72% of the cavity as a result of linker rotation. Encapsulation has a universal effect on the electrostatic potential (ESP), systematically decreasing the ESP at the metal center of each TMC in the TMC-34 data set, while minimally altering TMC metal partial charges. Collectively these observations support geometry-based screening of potential guests and suggest that encapsulation in Ga4L612-cages could electrostatically stabilize diverse cationic or electropositive intermediates. We highlight candidate guests with associated known reactivity and solubility most amenable for encapsulation in experimental follow-up studies.

Abstract: The phytocenotic potential of pasture ecosystems of the Tsimlyanskii sand massif using the ecological scales of humidity, soil reaction, and soil richness in mineral nitrogen of G. Ellenberg is studied. This work is based on landscape-bioecological and ecological-morphological research methods using methods for studying the structure, stability and development of plant communities. It has been established that the family types Poaceae, Fabaceae, and Asteraceaeplay the greatest role in projective coverage. The predominant life form of vegetation at all sites studied are is 40–71%. The average productivity of phytocenoses is 156–287 g/m2. The species composition and productivity of pasture phytocenoses changes noticeably depending on the humidity, physicochemical properties, and the richness of the soil in mineral nitrogen. On moist, non-drying, slightly acidic soils with an average nitrogen content, edificators are Agrostis caninaL., A. tenuisSibth., Thlaspi arvenseL., Typha angustifoliaL., T. latifoliaL., Tanacetum vulgareL., Phragmites australis(Cav.) Trin. ex Steud., and Scirpus lacustrisL. Under average moisture conditions, on slightly acidic soils with an average nitrogen content, edificators are Achillea millefoliumL., Astragalus arenariusL., Elytrigia repens(L.) Nevski, Medicago falcataL., and Phleum pratenseL. Under average moisture conditions, on slightly acidic soils rich in mineral nitrogen, edificators are Apera spica-venti(L.) P.Beauv., Atriplex tataricaL., and Calamagrostis epigeios(L.) Roth. Under average moisture conditions, on neutral soils with an average nitrogen content, edificators are Artemisia abrotanumL., Cirsium incanum(SG Gmel.) Fisch., Gypsophila paniculataL., Inula germanicaL., Juncus gerardiiLoisel., and Senecio erucifoliusL.On dry, slightly acidic soils with an average nitrogen content, edificators are Chamaecytisus ruthenicus(Fisch. ex Wol) and Festuca valesiacaGaudin.On dry, slightly acidic and mineral nitrogen-poor soils, edificators are Anisantha tectorum(L.) Nevski, Artemisia campestrisL., A. maritimaL., A. marschallianaSpreng., A. scopariaWaldst. & Kit., Bromopsis inermis(Leyss.) Holub, Crepis tectorumL., Koeleria glauca(Spreng.) DC., Leymus racemosus(Lam.) Tzvelev, Potentilla incanaP. Gaertn., B. Mey. & Scherb., Psammophiliella muralis(L.) Ikonn., and Stipa capillataL. Under conditions of sufficient and variable moisture, on neutral and slightly acidic soils with an average nitrogen content, edificators are Agropyron cristatumL. and Thlaspi arvenseL. In the brome–bushgrass–wormwood (Bromopsis inermis, Calamagrostis epigeios, Artemisia marschalliana) community, there is a large proportion of therophytes (22.9%), which indicates anthropogenic pressure on this territory.

Metal organochalcogenides (MOCs) are an emerging class of luminescent hybrid organic–inorganic semiconductors, whose structures and properties can be tuned by organic functionalization and substitutions of their metal and chalcogen elements. Herein, we present a new design strategy by heterocyclic modification, resulting in the transformation of prototypical two-dimensional (2D) silver phenylselenide (AgSePh) to a zero-dimensional (0D) silver pyridinylselenide (AgSePy) via the formation of Ag–N bonds. At room temperature, AgSePy shows strong and broad orange photoluminescence (PL; λmax= 636 nm, full-width-at-half-maximum = 111 nm, quantum yield = 64%) with a large 259 nm Stoke’s shift and a 3.4 μs lifetime. Using steady-state and time-resolved PL spectroscopy under varying temperature and oxygen conditions, we found AgSePy to exhibit air-stable luminescence and maintain a high PL quantum yield and a single exponential PL lifetime down to 4 K. Furthermore, AgSePy shows excellent thermal stability up to ∼250 °C and chemical stability against polar, nonpolar, and aqueous solvents at pH 3–14. Density functional theory calculations further confirm the 0D electronic structure. Finally, we successfully demonstrated the performance of AgSePy as an X-ray scintillator with an estimated light yield of ∼8,000 phe/MeV and a spatial resolution down to 0.080 ± 0.005 mm. Overall, this work provides a novel tactic to modify the structures and properties of MOCs, highlighting their structural richness and structure–property relationship, and introduces their new use as X-ray scintillators, encouraging further development in radiation detection and medical imaging.

We study active-site models of nonheme iron hydroxylases and their vanadium-based mimics using density functional theory to determine if vanadyl is a faithful structural mimic. We identify crucial structural and energetic differences between ferryl and vanadyl isomers owing to the differences in their ground electronic states, i.e., high spin (HS) for Fe and low spin (LS) for V. For the succinate cofactor bound to the ferryl intermediate, we predict facile interconversion between monodentate and bidentate coordination isomers for ferryl species but difficult rearrangement for vanadyl mimics. We study isomerization of the oxo intermediate between axial and equatorial positions and find the ferryl potential energy surface to be characterized by a large barrier of ca. 10 kcal/mol that is completely absent for the vanadyl mimic. This analysis reveals even starker contrasts between Fe and V in hydroxylases than those observed for this metal substitution in nonheme halogenases. Analysis of the relative bond strengths of coordinating carboxylate ligands for Fe and V reveals that all of the ligands show stronger binding to V than Fe owing to the LS ground state of V in contrast to the HS ground state of Fe, highlighting the limitations of vanadyl mimics of native nonheme iron hydroxylases.

The moving k nearest neighbor(MkNN) query finds the knearest neighbors of a moving query point continuously. The high potential of reducing the query processing cost as well as the large spectrum of associated applications have attracted considerable attention to this query type from the database community. This paper presents an incremental safe-region-based technique for answering MkNN queries, called the V*-Diagram.In general, a safe region is a set of points where the query point can move without changing the query answer. Traditional safe-region approaches compute a safe region based on the data objects but independent of the query location. Our approach exploits the current knowledge of the query point and the search space in addition to the data objects. As a result, the V*-Diagram has much smaller IO and computation costs than existing methods. The experimental results show that the V*-Diagram outperforms the best existing technique by two orders of magnitude.

Accurate speed measurement is mandatory for precision electric drives. These drives frequently utilize incremental position encoders for speed measurement as a derivative of the position in time. At present, the best practice is the implementation of the constant elapsed time (CET) methods, which operate with the position increment of multiples of four owing to the inaccuracies of the position encoder. The position increment defines the measurement time or the delay in the feedback, which strongly affects the performance of the speed loop. At low speeds, the position increment should be made smaller than four to keep the measurement delay within the limits of speed loop stability. However, the utilization of position increments smaller than four leads to high errors in speed estimation due to the uncompensated errors of the incremental encoder. Therefore, this study examined the errors of the incremental encoder to propose a calibration strategy for the synchronous CET speed estimation technique, which allows for accurate speed measurement at low speeds. The experimental results proved that the proposed method helps in decreasing the minimum measurable speed four times more than the original synchronous CET method with acceptable accuracy and computational complexity.

Hintergrund: Menschen mit Störung der Intelligenzentwicklung entwickeln häufig dissoziative Anfälle. Bei Psychotherapierenden bestehen oftmals große Unsicherheiten bei der Behandlung dieser Klientel. Ziel der Arbeit/Material und Methoden: Es erfolgt die Darstellung des Vorgehens mit speziellen Hinweisen zur Anpassung der Behandlung bei Menschen mit Störung der Intelligenzentwicklung. Ergebnisse und Diskussion: Die Behandlung dissoziativer Anfälle sollte bei Menschen mit Störung der Intelligenzentwicklung grundsätzlich gleich wie bei Normintelligenten erfolgen. Die erforderlichen Anpassungen sind mit etwas Übung leicht umzusetzen. Ein Umdenken in der Versorgung von psychisch kranken Menschen mit Störung der Intelligenzentwicklung ist daher dringend erforderlich und wünschenswert.

Purpose: FAST is a point of care ultrasound study that evaluates for the presence of free fluid, typically hemoperitoneum in trauma patients. FAST is an essential skill for Emergency Physicians. Thus, it requires objective evaluation tools that can reduce the necessity of direct observation for proficiency assessment. In this work, we use deep neural networks to automatically assess operators’ FAST skills. Methods: We propose a deep convolutional neural network for FAST proficiency assessment based on motion data. Prior work has shown that operators demonstrate different domain-specific dexterity metrics that can distinguish novices, intermediates, and experts. Therefore, we augment our dataset with this domain knowledge and employ fine-tuning to improve the model’s classification capabilities. Our model, however, does not require specific points of interest (POIs) to be defined for scanning. Results: The results show that the proposed deep convolutional neural network can classify FAST proficiency with 87.5% accuracy and 0.884, 0.886, 0.247 sensitivity for novices, intermediates, and experts, respectively. It demonstrates the potential of using kinematics data as an input in FAST skill assessment tasks. We also show that the proposed domain-specific features and region fine-tuning increase the model’s classification accuracy and sensitivity. Conclusions: Variations in probe motion at different learning stages can be derived from kinematics data. These variations can be used for automatic and objective skill assessment without prior identification of clinical POIs. The proposed approach can improve the quality and objectivity of FAST proficiency evaluation. Furthermore, skill assessment combining ultrasound images and kinematics data can provide a more rigorous and diversified evaluation than using ultrasound images alone.