60 Years of the 3Rs symposium: Lessons learned and the road ahead.

When The Principles of Humane Experimental Technique was published in 1959, authors William Russell and Rex Burch had a modest goal: to make researchers think about what they were doing in the laboratory - and to do it more humanely. Sixty years later, their groundbreaking book was celebrated for inspiring a revolution in science and launching a new field: The 3Rs of alternatives to animal experimentation. On November 22, 2019, some pioneering and leading scientists and researchers in the field gathered at the Johns Hopkins Bloomberg School of Public Health in Bal-timore for the 60 Years of the 3Rs Symposium: Lessons Learned and the Road Ahead. The event was sponsored by the Johns Hopkins Center for Alternatives to Animal Testing (CAAT), the Foundation for Chemistry Research and Initiatives, the Alternative Research & Development Foundation (ARDF), the American Cleaning Institute (ACI), the International Fragrance Association (IFRA), the Institute for In Vitro Sciences (IIVS), John "Jack" R. Fowle III, and the Society of Toxicology (SoT). Fourteen pres-entations shared the history behind the groundbreaking publication, international efforts to achieve its aims, stumbling blocks to progress, as well as remarkable achievements. The day was a tribute to Russell and Burch, and a testament to what is possible when people from many walks of life - science, government, and industry - work toward a common goal.

William Russell and Rex Burch published their book The Principles of Humane Experimental Technique in 1959. The book encouraged researchers to replace animal experiments where it was possible, to refine experiments with animals in order to reduce their suffering, and to reduce the number of animals that had to be used for experiments to the minimum. Sixty years later, a group of pioneering and leading scientists and researchers in the field gathered to share how the publi­cation came about and how the vision inspired international collaborations and successes on many different levels including new laws. The paper includes an overview of important milestones in the history of alternatives to animal experimentation.

Biventricular finite element modeling of the fetal heart in health and during critical aortic stenosis.

Finite Element simulations are a robust way of investigating cardiac biomechanics. To date, it has only been performed with the left ventricle (LV) alone for fetal hearts, even though results are likely different with biventricular (BiV) simulations. In this research, we conduct BiV simulations of the fetal heart based on 4D echocardiography images to show that it can capture the biomechanics of the normal healthy fetal heart, as well as those of fetal aortic stenosis better than the LV alone simulations. We found that performing LV alone simulations resulted in overestimation of LV stresses and pressures, compared to BiV simulations. Interestingly, inserting a compliance between the LV and right ventricle (RV) in the lumped parameter model of the LV only simulation effectively resolved these overestimations, demonstrating that the septum could be considered to play a LV-RV pressure communication role. However, stresses and strains spatial patterns remained altered from BiV simulations after the addition of the compliance. The BiV simulations corroborated previous studies in showing disease effects on the LV, where fetal aortic stenosis (AS) drastically elevated LV pressures and reduced strains and stroke volumes, which were moderated down with the addition of mitral regurgitation (MR). However, BiV simulations enabled an evaluation of the RV as well, where we observed that effects of the AS and MR on pressures and stroke volumes were generally much smaller and less consistent. The BiV simulations also enabled investigations of septal dynamics, which showed a rightward shift with AS, and partial restoration with MR. Interestingly, AS tended to enhance RV stroke volume, but MR moderated that down.

Rise In First-Time ERCP For Benign Indications >1 Year After Cholecystectomy Is Associated With Worse Outcomes.

BACKGROUND & AIMS: Greater availability of less invasive biliary imaging to rule out choledocholithiasis should reduce the need for diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in patients who have a remote history of cholecystectomy. The primary aims were to determine the incidence, characteristics, and outcomes of individuals who undergo first-time ERCP > 1 year after cholecystectomy (late-ERCP). METHODS: Data from a commercial insurance claim database (Optum Clinformatics) identified 583,712 adults who underwent cholecystectomy, 4,274 of whom underwent late-ERCP, defined as first-time ERCP for nonmalignant indications > 1 year after cholecystectomy. Outcomes were exposure and temporal trends in late-ERCP, biliary imaging utilization, and post-ERCP outcomes. Multivariable logistic regression was used to examine patient characteristics associated with undergoing late ERCP. RESULTS: Despite a temporal increase in the use of non-invasive biliary imaging (35.9% in 2004 to 65.6% in 2021, p<0.001), the rate of late-ERCP increased eight-fold: 0.5 to 4.2/1,000 person-years from 2005 to 2021, p<0.001). While only 44% of patients who underwent late-ERCP had gallstone removal, there were high rates of post-ERCP pancreatitis (7.1%), hospitalization (13.1%), and new chronic opioid use (9.7%). Factors associated with late-ERCP included concomitant disorder of gut-brain interaction (OR 6.48, 95%CI:5.88-6.91) and metabolic dysfunction steatotic liver disease (OR 3.27 95%CI:2.79-3.55) along with use of anxiolytic (OR 3.45 95%CI:3.19-3.58), anti-spasmodic (OR 1.60 95%CI:1.53-1.72), and chronic opioids (OR 6.24 95%CI:5.79-6.52). CONCLUSION: The rate of late-ERCP post-cholecystectomy is increasing significantly, particularly in patients with comorbidities associated with disorder of gut-brain interaction and mimickers of choledocholithiasis. Late-ERCPs are associated with disproportionately higher rates of adverse events, including initiation of chronic opioid use.

Epigenetic dissection of human blood group genes reveals regulatory elements and detailed characteristics of KEL and four other loci.

BACKGROUND: Blood typing is essential for safe transfusions and is performed serologically or genetically. Genotyping predominantly focuses on coding regions, but non-coding variants may affect gene regulation, as demonstrated in the ABO, FY and XG systems. To uncover regulatory loci, we expanded a recently developed bioinformatics pipeline for discovery of non-coding variants by including additional epigenetic datasets. METHODS: Multiple datasets including ChIP-seq with erythroid transcription factors (TFs), histone modifications (H3K27ac, H3K4me1), and chromatin accessibility (ATAC-seq) were analyzed. Candidate regulatory regions were investigated for activity (luciferase assays) and TF binding (electrophoretic mobility shift assay, EMSA, and mass spectrometry, MS). RESULTS: In total, 814 potential regulatory sites in 47 blood-group-related genes were identified where one or more erythroid TFs bound. Enhancer candidates in CR1, EMP3, ABCB6, and ABCC4 indicated by ATAC-seq, histone markers, and co-occupancy of 4 TFs (GATA1/KLF1/RUNX1/NFE2) were investigated but only CR1 and ABCC4 showed increased transcription. Co-occupancy of GATA1 and KLF1 was observed in the KEL promoter, previously reported to contain GATA1 and Sp1 sites. TF binding energy scores decreased when three naturally occurring variants were introduced into GATA1 and KLF1 motifs. Two of three GATA1 sites and the KLF1 site were confirmed functionally. EMSA and MS demonstrated increased GATA1 and KLF1 binding to the wild-type compared to variant motifs. DISCUSSION: This combined bioinformatics and experimental approach revealed multiple candidate regulatory regions and predicted TF co-occupancy sites. The KEL promoter was characterized in detail, indicating that two adjacent GATA1 and KLF1 motifs are most crucial for transcription.

Design and Extrusion-Based 3D Printing of Continuous Fiber Composites: Status, Challenges, and Opportunities.

This perspective article summarizes recent advancements in extrusion-based 3D printing of continuous fiber-reinforced polymers (CFRPs). It focuses on manufacturing techniques and computational design methodologies. While fused deposition modeling has been the primary method for printing thermoplastic CFRPs, recent innovations have enabled the printing of thermoset CFRPs using direct ink writing or similar techniques. These printing processes are also integrated with robotic arms to dramatically enhance manufacturing capabilities. Additionally, there has been notable progress in enhancing computational design methodologies to simultaneously optimize fiber distribution and topology of 3D printed CFRPs. The article also discusses future directions aimed at improving mechanical properties, scalability, multifunctionality, and predictability in CFRP 3D printing, which offer valuable perspectives for the development of this transformative manufacturing approach.

Four enzymes control natural variation in the steroid core of Erysimum cardenolides.

Plants commonly produce families of structurally related metabolites with similar defensive functions. This apparent redundancy raises the question of underlying molecular mechanisms and adaptive benefits of such chemical variation. Cardenolides, a class defensive compounds found in the wallflower genus Erysimum (L., Brassicaceae) and scattered across other plant families, show substantial structural variation, with glycosylation and hydroxylation being common modifications of a steroid core, which itself may vary in terms of stereochemistry and saturation. Through a combination of chemical mutagenesis and analysis of gene coexpression networks, we identified four enzymes involved in cardenolide biosynthesis in Erysimum that work together to determine stereochemistry at carbon 5 of the steroid core: Ec3ßHSD, a 3ß-hydroxysteroid dehydrogenase, Ec3KSI, a ketosteroid isomerase, EcP5ßR2, a progesterone 5ß-reductase, and EcDET2, a steroid 5α-reductase. We biochemically characterized the activity of these enzymes in vitro and generated CRISPR/Cas9 knockout lines to confirm activity in vivo . Cardenolide biosynthesis was not eliminated in any of the knockouts. Instead, mutant plants accumulated cardenolides with altered saturation and stereochemistry of the steroid core. Furthermore, we found variation in carbon 5 configuration among the cardenolides of 44 species of Erysimum , where the occurrence of some 5ß-cardenolides is associated with the expression and sequence of P5ßR2. This may have allowed Erysimum species to fine-tune their defensive profiles to target specific herbivore populations over the course of evolution. SIGNIFICANCE STATEMENT: Plants use an array of toxic compounds to defend themselves from attack against insects and other herbivores. One mechanism through which plants may evolve more toxic compounds is through modifications to the structure of compounds they already produce. In this study, we show how plants in the wallflower genus Erysimum use four enzymes to fine-tune the structure of toxic metabolites called cardenolides. Natural variation in the sequence and expression of a single enzyme called progesterone 5ß-reductase 2 partly explains the variation in cardenolides observed across the Erysimum genus. These alterations to cardenolide structure over the course of evolution suggests that there may be context-dependent benefits to Erysimum to invest in one cardenolide variant over another.

Screening H3 Histone Acetylation in a Wild Bird, the House Sparrow (Passer Domesticus).

Epigenetic mechanisms are increasingly understood to have major impacts across ecology. However, one molecular epigenetic mechanism, DNA methylation, currently dominates the literature. A second mechanism, histone modification, is likely important to ecologically relevant phenotypes and thus warrants investigation, especially because molecular interplay between methylation and histone acetylation can strongly affect gene expression. There are a limited number of histone acetylation studies on non-model organisms, yet those that exist show that it can impact gene expression and phenotypic plasticity. Wild birds provide an excellent system to investigate histone acetylation, as free-living individuals must rapidly adjust to environmental change. Here, we screen histone acetylation in the house sparrow (Passer domesticus); we studied this species because DNA methylation was important in the spread of this bird globally. This species has one of the broadest geographic distributions in the world, and part of this success is related to the way that it uses methylation to regulate its gene expression. Here, we verify that a commercially available assay that was developed for mammals can be used in house sparrows. We detected high variance in histone acetylation among individuals in both liver and spleen tissue. Further, house sparrows with higher epigenetic potential in the Toll Like Receptor-4 (TLR-4) promoter (i.e., CpG content) had higher histone acetylation in liver. Also, there was a negative correlation between histone acetylation in spleen and TLR-4 expression. In addition to validating a method for measuring histone acetylation in wild songbirds, this study also shows that histone acetylation is related to epigenetic potential and gene expression, adding a new study option for ecological epigenetics.

Photoinduced Magnetic Exchange-Jump Promotes Ground State Biradical Electron Spin Polarization.

Photoinduced electron spin polarization (ESP) is reported in the electronic ground states of three Pt(II) complexes comprised of two S = 1/2 nitronyl nitroxide (NN) radicals attached through different length para-phenylethynyl bridges to the 3,6 positions of a catecholate (CAT, donor) and 4,4'-di-tert-butyl-2,2'-bipyridine (bpy, acceptor). Complexes 1-3 have from 17 to 41 bonds separating NN radicals and display cw-EPR spectra consistent with |JNN-NN| ≫ |aN|, |JNN-NN| ≥ |aN|, and |JNN-NN| < |aN|, respectively, where JNN-NN is the magnetic exchange coupling between NN radicals in the electronic ground state, and aN is the isotropic 14N hyperfine coupling constant. Light-induced transient EPR spectra characterized as enhanced ground-state absorption were observed for all three complexes using 532 nm pulsed laser excitation into the ligand-to-ligand charge transfer (LL'CT) band of the (CAT)Pt(bpy) chromophore. The magnitude of the observed ESP increases in the order 1 < 2 < 3 and is inversely correlated with the magnitude of ground-state JNN-NN. In addition to the experimental observation of net absorptive polarization in 1-3, light excitation also produces multiplet polarization in 2. Since the weak dipolar coupling leads to a strong spectral overlap of the absorptive and emissive components, the multiplet polarization is not observed in 1 and 3 and is very weak in 2. The ability to spin-polarize multiple radical spins with a single photon is anticipated to advance new photoinduced multi qubit/qudit ESP protocols for quantum information science applications.

A machine-learning method for biobank-scale genetic prediction of blood group antigens.

A key element for successful blood transfusion is compatibility of the patient and donor red blood cell (RBC) antigens. Precise antigen matching reduces the risk for immunization and other adverse transfusion outcomes. RBC antigens are encoded by specific genes, which allows developing computational methods for determining antigens from genomic data. We describe here a classification method for determining RBC antigens from genotyping array data. Random forest models for 39 RBC antigens in 14 blood group systems and for human platelet antigen (HPA)-1 were trained and tested using genotype and RBC antigen and HPA-1 typing data available for 1,192 blood donors in the Finnish Blood Service Biobank. The algorithm and models were further evaluated using a validation cohort of 111,667 Danish blood donors. In the Finnish test data set, the median (interquartile range [IQR]) balanced accuracy for 39 models was 99.9 (98.9-100)%. We were able to replicate 34 out of 39 Finnish models in the Danish cohort and the median (IQR) balanced accuracy for classifications was 97.1 (90.1-99.4)%. When applying models trained with the Danish cohort, the median (IQR) balanced accuracy for the 40 Danish models in the Danish test data set was 99.3 (95.1-99.8)%. The RBC antigen and HPA-1 prediction models demonstrated high overall accuracies suitable for probabilistic determination of blood groups and HPA-1 at biobank-scale. Furthermore, population-specific training cohort increased the accuracies of the models. This stand-alone and freely available method is applicable for research and screening for antigen-negative blood donors.

Sensibilidad de la respuesta simpática cutánea y de la gammagrafía en el diagnóstico del síndrome dolor regional complejo / Sensitivity of the sympathetic skin response and scintigraphy in the diagnosis of complex regional pain syndrome

Objetivo: Evaluar la sensibilidad de la respuesta simpática cutánea (RSC) y compararla con la gammagrafía en pacientes con síndrome de dolor regional complejo diagnosticados según criterios de Budapest. Material y métodos: Se evaluó prospectivamente a 22 pacientes con síndrome de dolor regional complejo que acudieron al Servicio de Rehabilitación y Medicina Física entre enero-2018 y mayo-2022. La gammagrafía se consideró positiva si en la 1.a-2.a fase se apreció leve captación asimétrica y difusa, o cuando en la 3.a fase se apreció marcada captación periarticular del radioisótopo. La RSC era anormal si se observaba: a) ausencia de respuesta tras 20 estímulos; b) falta de habituación con permanencia de los estímulos mayor al 67,2%. Resultados: Edad 55,4±8,57 años. Síndrome de dolor regional complejo más frecuente en mujeres (90,9%), más común en miembros superiores (68,2%) que en inferiores (31,8%). En la RSC hemos observado respuesta normal (<67,2%) en 2 pacientes (11,1%), falta de RSC en 2 pacientes (11,1%) y falta de habituación (>67,2%) en 14 pacientes (77,8%). En total, 16 pacientes presentaron respuestas anormales o ausentes (88,8%). La sensibilidad diagnóstica de la gammagrafía es similar a la de la RSC (89,5 vs. 88,8%), sin diferencia estadística (p=0,6721). Conclusión: La Gammagrafía ha demostrado una sensibilidad similar a la RSC, aunque la simpleza, el bajo coste y la no invasividad de esta última técnica sugieren que podría ser más coste/efectiva y segura (no ionizante). La falta de habituación y la ausencia de respuesta podrían identificar patrones de respuesta y localizar la afectación en las vías aferente, central, eferente o post ganglionar.(AU)

Objective: To evaluate the sensitivity of sympathetic skin response (SSR) and compare it with scintigraphy in patients with complex regional pain syndrome diagnosed according to the Budapest criteria. Material and methods: Twenty-two patients with complex regional pain syndrome who attended the Rehabilitation and Physical Medicine Department between January-2018 and May-2022 have been prospectively evaluated. The scintigraphy was considered positive if in the 1st-2nd phase slight asymmetric and diffuse uptake was observed, or when in the 3rd phase marked periarticular radioisotope uptake was observed. SSR was abnormal if: a) no response after 20 stimuli; b) lack of habituation with permanence of the stimuli greater than 67.2%. Results: Age 55.4±8.57 years. Complex regional pain syndrome was more frequent in women (90.9%), more common in upper limbs (68.2%) than lower limbs (31.8%). In SSR, we have observed normal response (<67.2%) in 2 patients (11.1%), lack of SSR in 2 patients (11.1%) and lack of habituation (>67.2%) in 14 patients (77.8%). In total, 16 patients presented abnormal or absent responses (88.8%). The diagnostic sensitivity of scintigraphy is similar to that of SSR (89.5% vs 88.8%), with no statistical difference (P=.6721). Conclusion: Scintigraphy has shown similar sensitivity to SSR, although the simplicity, security, low cost, non-ionizing and non-invasiveness of the latter technique suggest that it could be more cost-effective. The lack of habituation and the absence of response could identify response patterns and localize the involvement in the afferent, central, efferent or post-ganglionic pathways.(AU)

Effect of Early vs Late Inguinal Hernia Repair on Serious Adverse Event Rates in Preterm Infants: A Randomized Clinical Trial.

Importance: Inguinal hernia repair in preterm infants is common and is associated with considerable morbidity. Whether the inguinal hernia should be repaired prior to or after discharge from the neonatal intensive care unit is controversial. Objective: To evaluate the safety of early vs late surgical repair for preterm infants with an inguinal hernia. Design, Setting, and Participants: A multicenter randomized clinical trial including preterm infants with inguinal hernia diagnosed during initial hospitalization was conducted between September 2013 and April 2021 at 39 US hospitals. Follow-up was completed on January 3, 2023. Interventions: In the early repair strategy, infants underwent inguinal hernia repair before neonatal intensive care unit discharge. In the late repair strategy, hernia repair was planned after discharge from the neonatal intensive care unit and when the infants were older than 55 weeks' postmenstrual age. Main Outcomes and Measures: The primary outcome was occurrence of any prespecified serious adverse event during the 10-month observation period (determined by a blinded adjudication committee). The secondary outcomes included the total number of days in the hospital during the 10-month observation period. Results: Among the 338 randomized infants (172 in the early repair group and 166 in the late repair group), 320 underwent operative repair (86% were male; 2% were Asian, 30% were Black, 16% were Hispanic, 59% were White, and race and ethnicity were unknown in 9% and 4%, respectively; the mean gestational age at birth was 26.6 weeks [SD, 2.8 weeks]; the mean postnatal age at enrollment was 12 weeks [SD, 5 weeks]). Among 308 infants (91%) with complete data (159 in the early repair group and 149 in the late repair group), 44 (28%) in the early repair group vs 27 (18%) in the late repair group had at least 1 serious adverse event (risk difference, -7.9% [95% credible interval, -16.9% to 0%]; 97% bayesian posterior probability of benefit with late repair). The median number of days in the hospital during the 10-month observation period was 19.0 days (IQR, 9.8 to 35.0 days) in the early repair group vs 16.0 days (IQR, 7.0 to 38.0 days) in the late repair group (82% posterior probability of benefit with late repair). In the prespecified subgroup analyses, the probability that late repair reduced the number of infants with at least 1 serious adverse event was higher in infants with a gestational age younger than 28 weeks and in those with bronchopulmonary dysplasia (99% probability of benefit in each subgroup). Conclusions and Relevance: Among preterm infants with inguinal hernia, the late repair strategy resulted in fewer infants having at least 1 serious adverse event. These findings support delaying inguinal hernia repair until after initial discharge from the neonatal intensive care unit. Trial Registration: ClinicalTrials.gov Identifier: NCT01678638.

Numerical study of the scattering of acoustic waves by an elliptic vortex.

The scattering of the acoustic waves generated by a monopolar source propagating through a two-dimensional elliptic vortex, fixed or convected by a uniform flow, is studied by solving the Linearized Euler Equations in Cartesian coordinates using the Discontinuous Galerkin Method. For a fixed vortex position, the number, amplitudes, and angular spreads of the acoustic interference beams resulting from the sound scattering are found to significantly depend on the orientation of the vortex major axis with respect to the direction of the incident waves and on the vortex maximum tangential velocity. In particular, additional interference beams are obtained at large observation angles for a more elliptical vortex. For a convected elliptic vortex, the interference beams are curved as the angle between the incident acoustic wave and the vortex major axis varies when the vortex travels in the downstream direction. As expected, the scattering of the acoustic waves leads to spectral broadening in this case. Moreover, the widths and the frequencies of the lateral lobes obtained in the spectra on both sides of the peak at the source frequency are different for elliptic and round vortices.

Ensuring fidelity: key elements to consider in disseminating a diabetes telemanagement program for underserved Hispanic/Latinos living with type 2 diabetes.

Background: The Hispanic/Latino population has greater risk (estimated >50%) of developing type 2 diabetes (T2D) and developing it at a younger age. The American Diabetes Association estimates costs of diagnosed diabetes in 2017 was $327 billion; with medical costs 2.3x higher than patients without diabetes. The purpose of this manuscript is to describe the methodology utilized in a randomized controlled trial aimed at evaluating the efficacy of a diabetes telemanagement (DTM) program for Hispanic/Latino patients with T2D. The intent is to provide information for future investigators to ensure that this study can be accurately replicated. Methods: This study was a randomized controlled trial with 240 participants. Eligible patients (Hispanic/Latino, aged 18+, living with T2D) were randomized to Comprehensive Outpatient Management (COM) or DTM. DTM was comprised of usual care, including routine clinic visits every three months, as well as: Biometrics (a tablet, blood glucose meter, blood pressure monitor, and scale); Weekly Video Visits (facilitated in the patient's preferred language); and Educational Videos (including culturally congruent diabetes self-management education and quizzes). COM consisted of usual care including routine clinic visits every three months. For this study, COM patients received a glucometer, glucose test strips, and lancets. Establishing a therapeutic nurse-patient relationship was a fundamental component of our study for both groups. First contact (post-enrollment) centered on ensuring that patients and caregivers understood the program, building trust and rapport, creating a non-judgmental environment, determining language preference, and establishing scheduling availability (including evenings and weekends). DTM were provided with a tablet which allowed for self-paced education through videos and weekly video visits. The research team and Community Advisory Board identified appropriate educational video content, which was incorporated in diabetes educational topics. Video visits allowed us to assess patient involvement, motivation, and nonverbal communication. Communicating in Spanish, and awareness of diverse Hispanic/Latino backgrounds was critical, as using relevant and commonly-used terms can increase adherence and improve outcomes. Shared decision-making was encouraged to make realistic health care choices. Conclusion: Key elements discussed above provide a framework for future dissemination of an evidence-based DTM intervention to meet the needs of underserved Hispanic/Latino people living with T2D.

A scoping review on upper extremity prostheses: Satisfaction, barriers, and their implications in resource-limited countries.

The rates of prosthetic abandonment are not extensively understood especially in resource-limited countries. A scoping review was conducted to examine the literature on the satisfaction with and barriers to using specifically upper limb prostheses. A systematic search of the literature identified 425 studies. After reviewing the articles using predetermined inclusion and exclusion criteria, 7 cross-sectional studies were included in the final review. Barriers to the use of upper limb prostheses include the characteristics of the prosthesis (type, comfort, weight, functionality, price, and availability) and individual patient factors (recent prosthetic user, level of amputation, congenital and accidental limb loss, pain, and duration between amputation and prosthetic fitting). Considering tailored prosthetic design and funding may result in improved prosthetic adherence.

1- and 2-Tetrazolylacetonitrile as Versatile Ligands for Laser Ignitable Energetic Coordination Compounds.

1- and 2-Tetrazolylacetonitrile (1- and 2-TAN) have been synthesized by the reaction of chloroacetonitrile with 1H-tetrazole under basic conditions. They further were reacted with sodium azide in the presence of zinc(II) chloride to form 5-((1H-tetrazol-1-yl)methyl)-1H-tetrazole (1-HTMT) and 5-((2H-tetrazol-2-yl)methyl)-1H-tetrazole (2-HTMT). The nitrogen-rich compounds have been applied as ligands for Energetic Coordination Compounds (ECCs) and show interesting coordinative behavior due to different bridging modes. The structural variability of the compounds has been proved by low-temperature X-ray analysis. The ECCs were analyzed for their sensitivities to provide information about the safety of handling and their capability to serve as primary explosives in detonator setups to replace the commonly used lead styphnate and azide. All colored ECCs were evaluated for their ignitability by laser initiation in translucent polycarbonate primer caps. In addition, the spin-crossover characteristics of [Fe(1-TAN)6](ClO4)2 were highlighted by the measurement of the temperature-dependent susceptibility curve.

Aphid Resistance Segregates Independently of Cardenolide and Glucosinolate Content in an Erysimum cheiranthoides (Wormseed Wallflower) F2 Population.

Plants in the genus Erysimum produce both glucosinolates and cardenolides as a defense mechanism against herbivory. Two natural isolates of Erysimum cheiranthoides (wormseed wallflower) differed in their glucosinolate content, cardenolide content, and their resistance to Myzus persicae (green peach aphid), a broad generalist herbivore. Both classes of defensive metabolites were produced constitutively and were not further induced by aphid feeding. To investigate the relative importance of glucosinolates and cardenolides in E. cheiranthoides defense, we generated an improved genome assembly, genetic map, and segregating F2 population. The genotypic and phenotypic analysis of the F2 plants identified quantitative trait loci, which affected glucosinolates and cardenolides, but not the aphid resistance. The abundance of most glucosinolates and cardenolides was positively correlated in the F2 population, indicating that similar processes regulate their biosynthesis and accumulation. Aphid reproduction was positively correlated with glucosinolate content. Although the overall cardenolide content had little effect on aphid growth and survival, there was a negative correlation between aphid reproduction and helveticoside abundance. However, this variation in defensive metabolites could not explain the differences in aphid growth on the two parental lines, suggesting that processes other than the abundance of glucosinolates and cardenolides have a predominant effect on aphid resistance in E. cheiranthoides.

Metal-Ligand Exchange Coupling Alters the Open-Shell Ligand Electronic Structure in a Bis(semiquinone) Complex.

The electronic structure of the bis(dioxolene) bridging ligand -SQ2Th2- is responsive to metal-ligand magnetic exchange coupling. Comparison of the crystal structure of (NiSQ)2Th2 to that of (ZnSQ)2Th2 indicates an open-shell biradical ground state for the dinuclear Ni(II) complex compared to the closed-shell quinoidal character found in the dinuclear Zn(II) complex. Consistent with a comparison of bond lengths obtained by X-ray diffraction, the analysis of the variable-temperature magnetic susceptibility data for crystalline (NiSQ)2Th2 yields reduced SQ-SQ radical-radical magnetic exchange coupling (JSQ-SQ = -203 cm-1) compared to that of (ZnSQ)2Th2 (JSQ-SQ = -321 cm-1). The reduced SQ-SQ exchange coupling in (NiSQ)2Th2 derives from an attenuation of the SQ spin densities, which in turn is derived from the Ni-SQ antiferromagnetic exchange interactions. This reduction in SQ--SQ exchange that we observe for (NiSQ)2Th2 correlates with an effective lengthening of the bridge unit by ∼2.1 Šrelative to that of (ZnSQ)2Th2. This magnitude of the effective increase in the bridge distance is consistent with the (NiSQ)2Th2 JSQ-SQ value lying between those of (ZnSQ)2Th2 and (ZnSQ)2Th3. The ability to modulate spin populations on an organic radical via pairwise Ni-SQ magnetic exchange interactions is a general way to affect electronic coupling in the Th-Th bridge. Our results suggest that metal-radical exchange coupling represents a powerful mechanism for tuning organic molecular electronic structure, with important implications for molecular electronics and molecular electron transport.

Utility of a Benchmarking Report for Balancing Infection Prevention and Antimicrobial Stewardship in Children with Complicated Appendicitis.

OBJECTIVE: To develop a severity-adjusted, hospital-level benchmarking comparative performance report for postoperative organ space infection and antibiotic utilization in children with complicated appendicitis. BACKGROUND: No benchmarking data exist to aid hospitals in identifying and prioritizing opportunities for infection prevention or antimicrobial stewardship in children with complicated appendicitis. METHODS: This was a multicenter cohort study using NSQIP-Pediatric data from 16 hospitals participating in a regional research consortium, augmented with antibiotic utilization data obtained through supplemental chart review. Children with complicated appendicitis who underwent appendectomy from 07/01/2015 to 06/30/2020 were included. Thirty-day postoperative OSI rates and cumulative antibiotic utilization were compared between hospitals using observed-to-expected (O/E) ratios after adjusting for disease severity using mixed effects models. Hospitals were considered outliers if the 95% confidence interval for O/E ratios did not include 1.0. RESULTS: 1790 patients were included. Overall, the OSI rate was 15.6% (hospital range: 2.6-39.4%) and median cumulative antibiotic utilization was 9.0 days (range: 3.0-13.0). Across hospitals, adjusted O/E ratios ranged 5.7-fold for OSI (0.49-2.80, P=0.03) and 2.4-fold for antibiotic utilization (0.59-1.45, P<0.01). Three (19%) hospitals were outliers for OSI (1 high and 2 low performers), and eight (50%) were outliers for antibiotic utilization (5 high and 3 low utilizers). Ten (63%) hospitals were identified as outliers in one or both measures. CONCLUSIONS: A comparative performance benchmarking report may help hospitals identify and prioritize quality improvement opportunities for infection prevention and antimicrobial stewardship, as well as identify exemplar performers for dissemination of best practices.

Implementing systematic melanoma risk assessment and risk-tailored surveillance in a skin cancer focussed dermatology clinic: A qualitative study of feasibility and acceptability to patients and clinic staff.

BACKGROUND: International bodies recommend that melanoma risk assessment should be integrated into skin cancer care provision, but evidence to support implementation is lacking. AIM: To explore the acceptability and feasibility of implementing personalised melanoma risk assessment and tailored patient education and skin surveillance within routine clinical care. METHODS: This prospective qualitative implementation study was informed by the Theoretical Framework of Acceptability (TFA). Personalised, systematic melanoma risk assessment was implemented in the dermatology clinic at the Melanoma Institute Australia, Sydney, Australia February-May 2021. Pre- and post-implementation observations and semi-structured interviews with patients and staff were conducted (September 2020-March 2021). Observational notes and interview transcript data were analysed thematically using the TFA as a classifying framework. RESULTS: A total of 37 h of observations were made, and 29 patients and 12 clinic staff were interviewed. We found that the delivery of personalised melanoma risk estimates did not impact on patient flow through the clinic. Dermatologists reported that the personalised risk information enhanced their confidence in assessing patient risk and recommending tailored surveillance schedules. Most patients reported that the risk assessment and tailored information were a beneficial addition to their care. Among patients whose risk deviated from their expectations, some reported feeling worried, confused or mistrust in the risk information, including those at lower risk who were recommended to decrease surveillance frequency. CONCLUSIONS: It is feasible and acceptable to patients and clinic staff to calculate and deliver personalised melanoma risk information and tailored surveillance as part of routine clinical care within dermatology clinics.