Narrow Distribution Research Articles

Updated distribution and new emerging populations of Cynometracebuensis F. Seid. (Fabaceae), a critically endangered endemic plant from the Philippines.

Cynometracebuensis F. Seid. is an endemic and threatened tree from the Philippines. The species was previously described to exclusively thrive in the Tabunan Forest of the Central Cebu Protected Landscape. Due to its narrow geographic distribution and threats from land conversion, slash-and-burn activities and non-regulated wood harvesting by locals, C.cebuensis was assessed as Critically Endangered (CR) under criteria B1a and B1b (as well as B2a and B2b) of the IUCN Red List in 2013. The present study provides new additional locations of C.cebuensis in the Municipalities of Argao and Minglanilla in Cebu along with population data and habitat characteristics for each site. Although new populations of C.cebuensis were discovered, it remains at significant risk of extinction in its natural habitat. Urgent and comprehensive conservation efforts are imperative to prevent its extinction. This paper provides the updated distribution map of Cynometracebuensis F. Seid, a critically endangered endemic species in the Philippines showing five (5) distribution records.

In-house CAD/CAM fabricated repositioning guide in maxillary repositioning after Le Fort I osteotomy

ObjectiveThis study aimed to compare the accuracy of two transferring methods, which are the intermediate splint made by computer-aided design (CAD)/computer-aided manufacturing (CAM) and the customized maxillary repositioning guide for orthognathic surgery. Materials and methodsPatient data regarding virtual surgical simulations were collected. For analyzing the accuracy, the postoperative cone-beam computed tomography and preoperative simulation data were superimposed. The x, y, and z coordinates were obtained at three landmarks in the maxillary dentition, and the linear and angular differences between the surgical simulation and the actual surgery were evaluated. ResultsThirty-three patients were included in this study, 16 in the splint group and 17 in the guide group. One coordinate in the guide group and nine in the splint group showed errors of >2 mm, with a statistically significant difference. There was no significant difference between the two groups in the three-dimensional error distance at each reference point. In most measurements, the interquartile range of the guide group showed a narrower distribution than that of the splint group. ConclusionIt is more advantageous to use a customized maxillary repositioning guide than an intermediate splint made via CAD/CAM to obtain an accuracy within the 2 mm discrepancy range.

Fabrication of mRNA encapsulated lipid nanoparticles using state of the art SMART-MaGIC technology and transfection in vitro

The messenger ribose nucleic acid (mRNA) in the form of Corona virus of 2019 (COVID-19) vaccines were effectively delivered through lipid nanoparticles (LNP) proving its use as effective carriers in clinical applications. In the present work, mRNA (erythropoietin (EPO)) encapsulated LNPs were prepared using a next generation state-of-the-art patented, Sprayed Multi Absorbed-droplet Reposing Technology (SMART) coupled with Multi-channeled and Guided Inner-Controlling printheads (MaGIC) technologies. The LNP-mRNA were synthesized at different N/P ratios and the particles were characterized for particle size and zeta potential (Zetasizer), encapsulation or complexation (gel retardation assay) and transfection (Fluorescence microscopy and ELISA) in MG63 sarcoma cells in vitro. The results showed a narrow distribution of mRNA-lipid particles of 200 nm when fabricated with SMART alone and then the size was reduced to approximately 50 nm with the combination of SMART-MaGIC technologies. The gel retardation assay showed that the N/P > 1 exhibited strong encapsulation of mRNA with lipid. The in vitro results showed the toxicity profile of the lipids where N/P ratio of 5 was optimized with > 50% cell viability. It can be concluded that the functional LNP-mRNA prepared and analyzed with SMART-MaGIC technologies, could be a potential new fabrication method of mRNA loaded LNPs for point-of-service or distributed manufacturing.

Installing a Trigger to Upcycle High-Density Polyethylene.

Creating C═C bonds as "weak" sites in the stable C-C chains of polyethylene (PE) is an appealing strategy to promote sustainable development of the polyolefin industry. Compared to methods, such as dehydrogenation and postpolymerization modification, the copolymerization of ethylene (E) and butadiene (BD) should be a convenient and direct approach to introduce C═C bonds in PE, whereas it encounters problems in controlling the composition and regularity of the copolymer due to the mismatched activities and mechanisms between the two monomers. Herein, we report by employing the amidinate gadolinium complex, controllable E/BD copolymerization was achieved, where BD was incorporated in the uniformly discrete 1,4 mode. The obtained copolymer possesses the same physical, mechanical, processing, and antioxygen (aging at 100 °C for 28 days) properties as commercial high-density-PE, which, strikingly, were degraded by C═C bonds into α,ω-telechelic oligomers with narrow distribution. These degraded functional products were transferred to compatibilizers via atom-transfer radical polymerization or immortal ring-opening polymerization, achieving upcycling.

A higher body mass index and increased syndesmophytes volume are associated with facet joints ankylosis on thoracic spine in patients with ankylosing spondylitis: a retrospective cohort study

ObjectiveTo investigate the association between syndesmophytes and facet joint (FJ) lesions in patients with ankylosing spondylitis (AS), and to identify clinical factors associated with FJ ankylosis (FJA) in thoracic segment.MethodsNinety-seven patients with AS who underwent thoracic spine computed tomography (CT) or chest CT and without completely thoracic spine fusion were included. FJ lesions were analyzed for the numbers and distribution of normal, ankylosis, erosions, joint-space narrowing, osteophytes, and subchondral sclerosis. The volume of vertebral syndesmophtes unit (VSU) and total thoracic syndesmophtes volume were separately calculated by Mimics software. Clinical factors associated with FJA were investigated using generalized estimation equation (GEE). The association between syndesmophtes volume and numbers of FJ structural lesions was analyzed using generalized additive mixed model (GAMM).Results2328 FJ and 1164 VSUs in thoracic spine were assessed. The majority FJ structural lesions were ankylosis (32.39%). FJA was more frequently seen in vertebrae with syndesmophytes formation (p < 0.001). GEE showed that patients with normal BMI (18.5–24.9 kg/m2) and high BMI (> 24.9 kg/m2) were more likely to have FJA in thoracic spine (odds rations [95% confidence interval]: 0.27(0.12–0.59), 1.45(1.03–8.57), respectively). GAMM showed that syndesmophytes volume increase the numbers of FJA (standard β = 0.009, p < 0.05) and decreased the numbers of normal FJ (standard β = -0.07, p < 0.01).ConclusionFJA was the most common FJ structural lesion in thoracic spine, and it increases linearly with syndesmophytes before the bridging syndesmophytes formed. A higher BMI (especially > 24.9 kg/m2) and increased syndesmophytes volume are associated with FJA in thoracic spine.

Silver-Mediated ARGET-ATRP of Reactive Acrylates Using TPMANMe2 Ligand: A Universal Strategy for Controlled Copolymerization.

A controlled polymerization using activated acrylate monomers via ARGET-ATRP is developed with a tris[(4-dimethylamino pyridyl)methyl]amine ligand to address issues with weaker ligands and monomers that can undergo postpolymerization functionalization. This catalyst system enables the polymerization of N-acryloxy succinimide, fluorinated monomers, and isocyanato ethyl acrylate under controlled homogeneous conditions, ensuring linear molecular-weight growth and low polydispersity. Two block copolymerization strategies produce amphiphilic copolymers with narrow molecular-weight distributions and customizable compositions, allowing for various postpolymerization functionalizations.

Miktoarm Star-polypept(o)ide-Based Polyion Complex Micelles for the Delivery of Large Nucleic Acids.

Miktoarm star polymers exhibit a captivating range of physicochemical properties, setting them apart from their linear counterparts. This study devised a synthetic pathway to synthesize cationic miktoarm stars utilizing polypept(o)ides (PeptoMiktoStars), comprising 3 or 6 polysarcosine (pSar) arms (AB3×100, AB6×50, overall 300) for shielding and a cross-linkable poly(S-ethylsulfonyl-l-homocysteine) (pHcy(SO2Et)20) block and a poly(l-lysine) ((pLys)20) block for nucleic acid complexation. Precise control over the DPn and narrow molecular weight distributions (D̵ ≈ 1.2) were achieved for both structures. Both PeptoMiktoStars efficiently complexed mRNA and pDNA into polyion complex micelles (PICMs). AB6-PICMs provided modest (mRNA) to high (pDNA) stability against glutathione and heparin sulfate (HS), while even cross-linked AB3-PICMs were susceptible to HS. All PICMs delivered pDNA and mRNA into D1 cells (over 80%) and Jurkat T cells (over 50%) in vitro. Despite payload- and cell-dependency, AB3 showed overall higher transfection efficiency, while AB6 demonstrated better shielding and enhanced stability.

Living anionic copolymerization of 1,3-pentadiene isomers with alpha-methylstyrene in the presence of 2,2-di(2-tetrahydrofuryl)propane

The synthesis of statistical copolymers of alpha-methylstyrene (AMS) and 1,3-pentadiene (PD) isomers in the presence of 2,2-di(2-tetrahydrofuryl)propane (DTHFP) by living carbanionic polymerization was investigated in this paper. To the best of our knowledge, either AMS or PD monomer was rather difficult to homopolymerize in non-polar solvents without the help of polar additives even at high temperature due to its low ceiling temperature or relatively high electron cloud density of the conjugated CC double bond. However, the combination of RLi initiator and DTHFP regulator (0.1<DTHFP/Li < 0.5) allowed the rapid synthesis of the well-defined poly(AMS-stat-PD) with controlled molar masses (up to 32.5 kDa) and relatively narrow molecular weight distributions (1.10 < ĐMs < 1.52). Calculation of reactivity ratios by the Kelen–Tüdos method suggested that AMS copolymerized much more readily to with (Z)-1,3-pentadiene (ZP) than with (E)-1,3-pentadiene (EP) under the same conditions, whereas the EP/AMS copolymer exhibited much lower dispersity. 1H NMR results indicated that the polymer chain was found to be a mixture of 1,2-addition and 1,4-addition units, in the absence of 3,4-units. Kinetic experiments also showed that the apparent activation energy of EP/AMS copolymerization was slightly higher than that of the ZP/AMS case. To ensure complete conversion of the monomer, the feed ratio of AMS (fAMS) must be controlled to be within 0.3. In addition, the incorporation rate of AMS into the polymer chain increased with the increase in the feed ratio of AMS monomer. DSC curves showed that the Tg of the resulting copolymers increased gradually and could reach up to 25 °C (FAMS = 47). Based on the observation of the anionic statistical copolymerization behavior, an interpretation of the formation mechanism is presented here.

Species delimitation in Xanthium sect. Acanthoxanthium (Heliantheae, Asteraceae) and the neglected species Xanthium argenteum

AbstractXanthium is a genus of annual herbaceous plants that stands out within Asteraceae for being wind‐pollinated, diclinous monoecious, and bearing solitary pistillate flowers in peculiar spiny structures (burs). Xanthium sect. Acanthoxanthium is native to South America and characterized by the presence of trifurcate spines at the base of the leaves. Past taxonomic treatments of the section have been contradictory, some recognising up to six species, others reducing all to a single polymorphic species. Altogether, 42 samples of X. sect. Acanthoxanthium were analysed, the vast majority taken from herbarium specimens between 20 and 160 years old. We sampled multiple specimens of X. spinosum from throughout its broad range as well as those taxa with narrower distributions, covering the whole range of morphological variation in the section. When possible, we included types and original material. We used Hyb‐Seq techniques to obtain information from about 1000 single‐copy nuclear genes and complete plastomes. Phylogenomic data were submitted to coalescent‐based species delimitation approaches (SPEEDEMON). Additionally, we performed geometric morphometric analysis of leaf outlines. The results strongly support the identification of four lineages in the section favouring the acceptance of four of the hitherto described species, i.e., X. ambrosioides, X. argenteum, X. catharticum, and X. spinosum. These results were to some extent corroborated by morphometric analyses. While X. ambrosioides was well distinct from X. spinosum based on leaf morphology, such difference was not observed between X. spinosum and X. catharticum. However, X. catharticum differs from X. spinosum in its ecological requirements, being a species rather adapted to high‐mountain environments of the Neotropics. Intriguingly, X. argenteum – a taxon described from a single herbarium collection – was also inferred as a species.

Nanoporous Aramid Nanofiber Separators with High Modulus and Thermal Stability for Safe Lithium-Ion Batteries.

Developing high-safety separators is a promising strategy to prevent thermal runaway in lithium-ion batteries (LIBs), which stems from the low melting temperatures and inadequate modulus of commercial polyolefin separators. However, achieving high modulus and thermal stability, along with uniform nanopores in these separators, poses significant challenges. Herein, the study presents ultrathin nanoporous aramid nanofiber (ANF) separators with high modulus and excellent thermal stability, enhancing the safety of LIBs. These separators are produced using a microfluidic-based continuous printing strategy, where the flow thickness can be meticulously controlled at the micrometer scale. This method allows for the continuous fabrication of nanoporous ANF separators with thicknesses ranging from 1.6 ± 0.1µm to 2.7 ± 0.1µm. Thanks to the double-side solvent diffusion, the separators exhibit controllably uniform pore sizes with a narrow distribution, spanning from 40 ± 5nm to 105 ± 9nm, and a high modulus of 3.3 ± 0.5GPa. These nanoporous ANF separators effectively inhibit lithium dendrite formation, resulting in a high-capacity retention rate for the LIBs (80% after 240 cycles). Most notably, their robust structural and mechanical stability at elevated temperatures significantly enhances LIB safety under transient thermal abuse conditions, thus addressing critical safety concerns associated with LIBs.

Two-step and explosive synchronization in frequency-weighted Kuramoto model

We explore the dynamics of interacting phase oscillators in the generalized Kuramoto model with frequency-weighted couplings, focusing on the interplay of frequency distribution and network topology on the nature of transition to synchrony. We explore the impact of heterogeneity in the network topology and the frequency distribution. Our analysis includes unimodal (Gaussian, truncated Gaussian, and uniform) and bimodal frequency distributions. For a unimodal Gaussian distribution, we observe that in comparison to fully-connected network, the competition between topological and dynamical hubs hinders the transition to synchrony in the scale-free network, though explosive synchronization eventually happens. However, in the absence of very large frequencies, the transition is gradual. While uniform frequency distributions lead to explosive synchronization. In bimodal distributions, narrow distribution produce a two-step transition. In this case, central frequencies dominate the dynamics, overshadowing the topological features of the network. For wider bimodal distributions, scale-free network exhibits a gradual increase in the order parameter, whereas in fully-connected networks a first-order transition happens. These results specifically elucidate the mechanisms driving two-step and explosive synchronization in frequency-weighted Kuramoto models, offering new insights into managing synchronization phenomena in complex networks like power grids, neural systems, and social systems.

Integrative taxonomy and biogeography of the genus Oxytrechus (Coleoptera: Carabidae: Trechini) in the tropical alpine ecosystem of Ecuadorian Andes, with the description of six new species

Summary This study presents a taxonomic revision of the species of the ground beetle genus Oxytrechus Jeannel, 1927 that inhabit the superpáramo of the Andes of Ecuador, which constitutes the uppermost zone of the tropical alpine ecosystem, above 4200 m. Sixteen species, displayed in three clades, were recorded in this environment, six of which are described as new: Oxytrechus antisanae n. sp. (Mt Antisana), O. giachinoi n. sp. (Mt Illiniza), O. hamatus n. sp. (Mt Atacazo and Pichincha), O. prunai n. sp. (Mt Guamaní), O. reflexus n. sp. (Mt Illiniza and Mt Corazón), and O. robbiolai n. sp. (Mt Pichincha). New distributional data are presented for O. chioriae Quéinnec & Ollivier, 2019, O. lallemandi Jeannel, 1927, O. moreti Mateu, 1988 and O. zoiai Casale & Sciaky, 1985. The first molecular phylogeny of the group, based on fragments of four mitochondrial and two nuclear genes, is given. Dichotomous identification keys are provided to the species groups and the included species. Based on systematic sampling, Oxytrechus exhibits the highest degree of microendemism among páramo ground beetles. No species has been found in more than two sky islands, and half of the species recorded in the superpáramo are single-mountain endemics. As regards their conservation status, eight species (two thirds) can be classified as vulnerable or endangered, due to a mix of low abundance, narrow distribution range, microendemism, limited ecological tolerance, habitat destruction and effects of climate change.

Conservation status of three rare endemic Phaseolus bean (Leguminosae, Phaseoleae) species of Costa Rica

We aimed at an inventory of all populations of wild Phaseolus (bean) species in Costa Rica, in relation to future plant breeding. During the field work in 2003–2018, three new and rare bean species (i.e. P. albicarminus, P. angucianae and P. hygrophilus) were found in different montane forest habitats which originally occupy a small acreage. Field observations, together with satellite images, indicate deforestation due to coffee plantations or pastures. To date only eleven populations of these species are known, distributed along the Talamanca and Fila Cruces mountainous ranges, making them endemic. Their narrow distribution, deforestation affecting the original habitats, and occurrence outside established and enforced protected areas motivate the assessment of their conservation status as ‘Endangered' (EN).

Multi-functional RAFT reagent to prepare fluorescent hyper-branched macromolecular probes for the detection of Fe3+ ions

Reversible addition-fragmentation chain transfer (RAFT) polymerization has the advantages of precise control, high yield, and narrow molecular weight distribution. These merits make it an ideal method for the preparation of hyper-branched fluorescent polymers (FL-HBPs). In this work, a multi-functional RAFT reagent (AVCT-NLP) was prepared for the synthesis of monodisperse FL-HBPs. Firstly, dithionate compound (CN1) containing a CC double bond was synthesized by the reaction of 4-nitrophenol with 1-(bromomethyl)-4-vinylbenzene. Subsequently, the NO2 group on CN1 was reduced to NH2, and the −Br on the 4-bromo-1,8-naphthalic anhydride was substituted to emit fluorescence. Finally, the fluorophore was introduced by the reaction of NH2 with the anhydride on the naphthalene ring to obtain AVCT-NLP which contains fluorophore, dithionate, and CC double bond in one molecule. AVCT-NLP was then used to synthesize the homopolymer (PAVCT-NLP) as both monomer and RAFT reagent. Moreover, PAVCT-NLP served as a macromolecular RAFT reagent, and hydrophilic monomer methacrylic acid (MAA) or 3-butene-1,2-diol were polymerized to obtain amphiphilic hyper-branched polymers (FL-AHBP-1, FL-AHBP-2). All the as-prepared macromolecules (PAVCT-NLP, FL-AHBP-1, and FL-AHBP-2) exhibited specific recognition and high sensitivity for Fe3+. The fluorescence quenching reached up to 74.4 %, with the limit of detection (LOD) as low as 1.82 nM. Additionally, the probe demonstrated pH stability and environmental adaptability. Due to the multi-functional structures of AVCT-NLP, it could be subjected to RAFT polymerization to obtain a monodisperse hyper-branched polymer. All polymers have a high fluorophore density and the polydispersity index (PDI) of the polymer is close to 1.00. This paper provided an effective approach for synthesizing polymer fluorescent probes with versatile structure and fluorescence properties in future applications.

Synergistic Effect of Ionic Liquid and Embedded QDs on 2D Ferroelectric Perovskite Films with Narrow Phase Distribution for Self-Powered and Broad-Band Photodetectors.

2D layered metal halide perovskites (MHPs) are a potential material for fabricating self-powered photodetectors (PDs). Nevertheless, 2D MHPs produced via solution techniques frequently exhibit multiple quantum wells, leading to notable degradation in the device performance. Besides, the wide band gap in 2D perovskites limits their potential for broad-band photodetection. Integrating narrow-band gap materials with perovskite matrices is a viable strategy for broad-band PDs. In this study, the use of methylamine acetate (MAAc) as an additive in 2D perovskite precursors can effectively control the width of the quantum wells (QWs). The amount of MAAc greatly affects the phase purity. Subsequently, PbSe QDs were embedded into the 2D perovskite matrix with a broadened absorption spectrum and no negative effects on ferroelectric properties. PM6:Y6 was combined with the hybrid ferroelectric perovskite films to create a self-powered and broad-band PD with enhanced performance due to a ferro-pyro-phototronic effect, reaching a peak responsivity of 2.4 A W-1 at 940 nm.

Development of Mixed Micelles for Enhancing Fenretinide Apparent Solubility and Anticancer Activity Against Neuroblastoma Cells.

The purpose of the study was to evaluate the suitability of mixed micelles prepared with D-α-tocopheryl polyethylene glycol succinate (TPGS) and 1,2- distearoyl-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-PEG) to encapsulate the poorly soluble anticancer drug fenretinide (4-HPR). After assaying the solubilization ability of the surfactants by the equilibrium method, the micelles were prepared using the solvent casting technique starting from different 4-HPR:TPGS: DSPE-PEG w/w ratios. The resulting formulations were investigated for their stability under storage conditions and upon dilution, modelling the reaching of physiological concentrations after intravenous administration. The characterization of micelles included the determination of DL%, EE %, particle size distribution, Z-potential, and thermal analysis by DSC. The cytotoxicity studies were performed on HTLA-230 and SK-N-BE-2C neuroblastoma cells by the MTT essay. The colloidal dispersions showed a mean diameter of 12 nm, negative Zeta potential, and a narrow dimensional distribution. 4-HPR was formulated in the mixed micelles with an encapsulation efficiency of 88% and with an increment of the apparent solubility of 363-fold. The 4-HPR entrapment remained stable up to the surfactants' concentration of 2.97E-05 M. The loaded micelles exhibited a slow-release behaviour, with about 28% of the drug released after 24 h. On the most resistant SK-N-BE-2C cells, the encapsulated 4-HPR was significantly more active than free 4-HPR in reducing cell viability. Loaded micelles demonstrated their suitability as a new adjuvant tool potentially useful for the treatment of neuroblastoma.

Pseudomorphic synthesis of pore size-tunable mesoporous silica spherical particles and their application for the fraction of low-molecular-weight heparin.

In this study, spherical silica with pore size varied from 30 to 200 Å was synthesized by pseudomorphic transformation at atmospheric pressure. 40-80 Å silica particles with a narrow pore distribution were obtained by using quaternary amine cationic surfactants and different kinds of swelling agents, including polypropylene glycol, 1,3,5-trimethylbenzene, alkanes, and alkanols. Alkyl imidazolium ionic liquid surfactants were used to synthesize large pore size distribution silica spheres with pore sizes in the range of 110-200 Å. All these silica particles can be synthesized under mild conditions within 12h, which provides a facile synthesis method for the preparation of a chromatographic matrix with tunable pore size. The method is reproducible and the relative standard deviation of silica sphere pore structure parameters in scaled-up preparations is less than 6%. The pore size on the fraction of low-molecular-weight heparin (LMWH) was investigated in size exclusion chromatography. Matrixes with different pore size distributions have various size exclusion regions. By using UPS-60-Diol columns in a twin-column recirculation separation process, LMWH with>85% heparin with molecular weight within the range of 3000-8000Da were separated in five-column volumes.

Assessing Team Performance in a Longitudinal Neonatal Resuscitation Simulation Training Program: Comparing Validity Evidence to Select the Best Tool.

Introduction Neonatal resuscitation is a high-acuity, low-occurrence event that requires ongoing practice by interprofessional teams to maintain proficiency.Simulation provides an ideal platform for team training and evaluation of team performance. Our simulation center supports a longitudinal in situ simulation training program for delivery room teams. In addition to adherence to the Neonatal Resuscitation Program standards, team performance assessment is an essential component of program evaluation and participant feedback. Multiple published teamwork assessment tools exist. Our objective was to select the tool with the best validity evidence for our program's needs. Methods We used Messick's framework to assess the validity of evidence for potential teamwork assessment tools. Four possible tools were identified from the literature: the Mayo High Performance Teamwork Scale (Mayo), Team Performance Observation Tool (TPOT), Clinical Teamwork Scale (CTS), and Team Emergency Assessment Measure (TEAM). Relevant context included team versus individual focus, external evaluator versus self-evaluation, and ease of use (which included efficiency, clarity of interpretation, and overall assessment). Three simulation experts identified consensus anchors for each tool and independently reviewed and scored 10 pre-recorded neonatal resuscitation simulations. Raters assigned each tool a rating according to efficiency, ease of interpretation, and completeness of teamwork assessment. Interrater reliability (IRR) was calculated using intraclass correlation for each tool across the three raters. Average team performance scores for each tool were correlated with neonatal resuscitation adherence scores for each video using Spearman's rank coefficient. Results There was a range of IRR between the tools, with Mayo having the best (single 0.55 and multi 0.78). Each of the three raters ranked Mayo optimally in terms of efficiency (mean 4.66 + 0.577) and ease of use (4+1). However, TPOT and CTS scored highest (mean 4.66 ± 0.577) for overall completeness of teamwork assessment. There was no significant correlation to NRP adherence scores for any teamwork tool. Conclusion Of the four tools assessed, Mayo demonstrated moderate IRR and scored highest for its ease of use and efficiency, though not completeness of assessment. The remaining three tools had poor IRR, which is not an uncommon problem with teamwork assessment tools. Our process emphasizes the fact that assessment tool validity is contextual. Factors such as a relatively narrow (and high) performance distribution and clinical context may have contributed to reliability challenges for tools that offered a more complete teamwork assessment.

Direct numerical simulation of dispersion and mixing in gas–liquid Dean-Taylor flow with influence of a 90° bend

Gas-liquid capillary flow finds widespread applications in reaction engineering, owing to its ability to facilitate precise control and efficient mixing. Incorporating compact and regular design with Coiled Flow Inverter (CFI) enhances process efficiency due to improved mixing as well as heat and mass transfer leading to a narrow residence time distribution. The impact of Dean and Taylor flow phenomena on mixing and dispersion within these systems underscores their significance, but is still not yet fully understood. Direct numerical simulation based on finite element method enables full 3D resolution of the flow field and detailed examination of laminar flow profiles, providing valuable insights into flow dynamics. Notably, the deflection of flow velocity from the center axis contributes is followed by tracking of particle with defined starting positions, aiding in flow visualization and dispersion characterization. In this CFD study, the helical flow with the influence of the centrifugal force and pitch (Dean flow) as well as the capillary two-phase flow (Taylor bubble) is described and characterized by particle dispersion and related histograms. Future prospects in this field include advancements in imaging techniques to capture intricate flow patterns, as well as refined particle tracking methods to better understand complex flow behavior.

Shape-persistent ladder molecules exhibit nanogap-independent conductance in single-molecule junctions.

Molecular electronic devices require precise control over the flow of current in single molecules. However, the electron transport properties of single molecules critically depend on dynamic molecular conformations in nanoscale junctions. Here we report a unique strategy for controlling molecular conductance using shape-persistent molecules. Chemically diverse, charged ladder molecules, synthesized via a one-pot multicomponent ladderization strategy, show a molecular conductance (d[log(G/G0)]/dx ≈ -0.1 nm-1) that is nearly independent of junction displacement, in stark contrast to the nanogap-dependent conductance (d[log(G/G0)]/dx ≈ -7 nm-1) observed for non-ladder analogues. Ladder molecules show an unusually narrow distribution of molecular conductance during dynamic junction displacement, which is attributed to the shape-persistent backbone and restricted rotation of terminal anchor groups. These principles are further extended to a butterfly-like molecule, thereby demonstrating the strategy's generality for achieving gap-independent conductance. Overall, our work provides important avenues for controlling molecular conductance using shape-persistent molecules.