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This article describes a positive-sequence model to represent two widely reported droop-controlled grid-forming inverters for transmission system transient stability simulation studies. Methods of how to develop the equivalent voltage source behind impedance to represent inverters with and without inner control loops, modeling of P-f and Q-V droop controls, active and reactive power limiting modeling, and modeling of fault current limiting controls have been described in detail. The model was implemented in commercially available positive-sequence simulation tools and compared with detailed electromagnetic transient models in both a single-grid-forming-inverter infinite-bus system and a modified IEEE 39-bus system. Finally, the model was tested on the U.S. Western Interconnection system. The study results showed that the model has a good level of accuracy compared to the detailed EMT models, and at the same time also achieves a high computational efficiency, making it suitable for large-scale transmission system simulation studies.

Chemical upcycling of plastic waste into high-value materials has the potential to contribute to a more sustainable plastic economy. We report the synthesis of high-value ionomers directly from commodity polyolefins enabled by amidyl radical-mediated C–H functionalization. The use of thiosulfonates as a linchpin functionality for the group transfer of a variety of heteroaryl groups provided tunable incorporation of ionizable functionality onto a variety of polyolefin substrates, including postconsumer polyethylene packaging waste. Synthetic, structural, and thermomechanical studies provided a comprehensive understanding of both structure–reactivity and structure–property relationships for polyolefin ionomers. X-ray scattering experiments conducted in the solid and melt states confirm the presence of ionic multiplets that serve as physical cross-links both below and above the melting temperature of polyolefin crystallites. The incorporation of ionic groups into the polyolefins yielded materials with significantly enhanced melt strength and tensile toughness. We anticipate that this approach to access performance-advantaged polyolefin ionomers from commodity substrates or plastic waste will enhance sustainability efforts and lead to new opportunities for this versatile class of thermoplastics.

Spatial omics enables the molecular profiling of cells with the tissue context preserved. A new analytic approach shows how cellular neighborhood analysis and feature augmentation can spatially connect and cluster millions of cells into higher-order functional units.

This study deals with the application of data reconciliation to wastewater treatment processes which are subject to dynamic conditions and therefore do not reach a steady-state behaviour sensu stricto. The SHARON partial nitritation process, which is operated cyclically with alternating aerated and anoxic periods, is studied as an example. The collected data long-term dynamic data set was split up into data subsets corresponding with different pseudo-steady-state operations, which allowed a better gross error detection. Mass balances were set up taking into account off-gas measurements besides liquid phase measurements and including kinetic relations between measurements based on the biological conversions in the reactor. As a result, a higher number of variables could be reconciled, more key variables could be identified, and gross error detection was facilitated. In order to draw conclusions on the process performance in a shorter period of operation, e.g., on the N2O emission factor, the average value of the whole data set should be used with caution. The strong dependence of infiltrated air on the aeration regime and gross error in grab sampling (magnitude of 20%) had a substantial impact on calculating N2O emission. It is recommended that the process performance indicators are derived and checked separately for steady state data subsets to guarantee reliable outcomes.

α-Diimine palladium complexes incorporating phenanthryl- and 6,7-dimethylphenanthrylimino groups have been synthesized and characterized. The (diimine)PdMeCl complexes prepared from 2,3-butanedione and acenaphthenequinone bearing the unsubstituted phenanthrylimino groups, 12aand 14a, respectively, exist as a mixtures of synand antiisomers in a ca. 1:1 ratio. Separation and X-ray diffraction analysis of 14a-synand 14a-antiisomers confirms the syn/antiassignments. The barrier to interconversion of 14a-synand 14a-antivia ligand rotation, ΔG⧧, was found to be 25.5 kcal/mol. The corresponding (diimine)PdMeCl complex prepared from acenaphthenequinone and incorporating the 6,7-dimethylphenanthrylimino group exists solely as the antiisomer, 14b, due to steric crowding which destabilizes the synisomer. Analogous (diimine)NiBr2complexes were prepared from 2,3-butanedione incorporating the phenanthrylimino group, 16a, and the 6,7-dimethylphenanthrylimino group, 16b. Nickel-catalyzed polymerizations of ethylene were carried out by activation of the dibromide complexes 16a,busing various aluminum alkyl activators. Complex 16ayields a bimodal distribution polymer, the low-molecular-weight fraction originating from the synisomer and the high-molecular-weight fraction arising from the antiisomer. Polymerizations carried out by 16byield only high-molecular-weight polymers with monomodal distributions due to the existence of a single isomer (anti) as the active catalyst. All polymers are linear or nearly so. All catalysts are highly active, but catalysts derived from 16bare somewhat more active than 16aand exhibit turnover frequencies generally over 106and up to 5 × 106per hour (40 °C, 27.2 atm ethylene, 15 min). Active palladium ethylene oligomerization catalysts were generated by conversion of the neutral methyl chloride complexes 14a,bto the cationic nitrile complexes 15a,bvia halide abstraction.

New neutral nickel and palladium ethylene polymerization catalysts have been prepared that incorporate an anionic (N,O) chelating ligand. Extensive axial shielding is provided by two 3,5-dichloroaryl moieties in a “sandwich” orientation. Such shielding results in an exceptionally slow rate of chain transfer relative to migratory insertion in the nickel catalyst, and thus highly controlled polymerization of ethylene is observed, leading to lightly branched ultra-high molecular weight polyethylene with Mnvalues up to 4.1 × 106g/mol. The analogous palladium catalysts provide the means for a detailed mechanistic study of chain propagation in an electronically asymmetric neutral palladium catalyst. Both isomers of the methyl ethylene complex can be generated and observed at low temperatures allowing experimental elucidation of mechanistic details of chain propagation probed in other electronically asymmetric systems only through DFT studies or by examination of model studies. The barrier to migratory insertion in these complexes is ca. 19.2 kcal/mol. Investigation of the equilibration of the methyl ethylene isomers in the presence of excess ethylene showed the isomerization rate is dependent on ethylene concentration. This is the first direct proof that isomerization in these alkyl ethylene intermediates is catalyzed by ethylene. Furthermore, isomer equilibration is much faster than migratory insertion so that the barriers for insertion of individual isomers cannot be determined.

Nickel and palladium complexes bearing “sandwich” diimine ligands with perfluorinated aryl caps have been synthesized, characterized, and explored in ethylene polymerization reactions. The X-ray crystallographic analysis of the precatalysts 16and 6bshows differences from their nonfluorinated analogues 17and 19, with the perfluorinated aryl caps centered precisely over the nickel and palladium centers, which results in higher buried volumes of the metal centers relative to the nonfluorinated analogues. The sandwich diimine-palladium complexes 5aand 5bcontaining perfluorinated aryl caps polymerize ethylene in a controlled fashion with activities that are substantially increased compared with their nonfluorinated analogues. Migratory insertion rates in relevant methyl ethylene complexes agree with the activities exhibited in bulk polymerization experiments. DFT studies suggest that facility of ethylene rotation from its preferred orientation perpendicular to the Pd-alkyl bond into a parallel in-plane conformation contributes to the higher polymerization activity for 5brelative to 18a.For these palladium systems, polymer molecular weights can be controlled via hydrogen addition (hydrogenolysis), which is unusual for late-transition-metal-catalyzed olefin polymerizations with no catalyst deactivation occurring. Sandwich diimine-nickel complexes 6aand 6bwith perfluorinated aryl caps show ethylene polymerization activities that are about half of those of classical tetraisopropyl-substituted catalyst 2but again are more active than the analogous nonfluorinated sandwich complexes. Ethylene polymerizations exhibit living behavior, and branched ultrahigh-molecular-weight polyethylenes (UHMWPEs) with very low-molecular-weight distributions (less than 1.1) are obtained. The activated nickel catalysts are stable in the absence of monomer and show good long-term stability at 25 °C.

Delay discounting refers to the devaluation of a reward given increasing delays to delivery. Similarly, effort discounting refers to the devaluation of a reward given increasing effort required to obtain it. Individuals with substance use disorder show higher rates of delay discounting, exacerbating short‐term positive reinforcement at the expense of long‐term consequences. This study explores how effort discounting compares to delay discounting behavior among alcohol users as well as how these preferences change between monetary and alcohol rewards. A total of 100 participants completed an online survey through Amazon Mechanical Turk. Participant alcohol use was evaluated using DSM‐5 and the Alcohol Use Disorders Identification Test criteria. All participants completed 4 randomized discounting tasks involving delay or effort discounting, in which the reward was money or alcohol. A follow‐up experiment (n= 423) added the alcohol purchase task to assess alcohol valuation. Individuals with greater alcohol use disorder (AUD) severity discounted future money and alcohol significantly more than those with less AUD. However, individuals meeting more DSM‐5 criteria were only willing to perform more effort for alcohol. The follow‐up experiment replicated these findings and demonstrated that individuals with greater AUD also showed an increased valuation of alcohol and alcohol value‐mediated effort discounting. These results suggest that individuals with greater AUD were less willing to wait for money or alcohol. While all participants were willing to work for money regardless of AUD severity, individuals with greater AUD showed increased valuation of alcohol drinks and were willing to exert more effort to obtain alcohol. Together, these results paint a picture of individuals with increased AUD as both more impulsive and willing to work to obtain alcohol, contributing to our understanding of decision making among individuals who abuse substances. Participants (n= 423) completed four delay or effort discounting tasks, with money or alcohol rewards. DSM‐5 criteria for alcohol use disorder was positively associated with delay discounting for money and alcohol (Panels A and C). Conversely, DSM‐5 criteria was negatively associated with effort discounting for alcohol (Panel D), suggesting that greater AUD severity predicts inability to wait (increased delay discounting) but willingness to work for alcohol (low effort discounting). No relationship emerged between DSM‐5 criteria and monetary effort discounting (Panel B).

Persistent human papillomavirus (HPV) infection is responsible for at least 5% of human malignancies. Most HPV-associated cancers are initiated by the HPV16 genotype, as confirmed by detection of integrated HPV DNA in cells of oral and anogenital epithelial cancers. However, single-cell RNA sequencing may enable prediction of HPV involvement in carcinogenesis at other sites. We conducted single-cell RNA sequencing on keratinocytes from a mouse transgenic for the E7gene of HPV16 and showed sensitive and specific detection of HPV16-E7mRNA, predominantly in basal keratinocytes. We showed that increased E7mRNA copy number per cell was associated with increased expression of E7 induced genes. This technique enhances detection of active viral transcription in solid tissue and may clarify possible linkage of HPV infection to development of squamous cell carcinoma.

Heterogeneity of cell states represented in pluripotent cultures has not been described at the transcriptional level. Since gene expression is highly heterogeneous between cells, single-cell RNA sequencing can be used to identify how individual pluripotent cells function. Here, we present results from the analysis of single-cell RNA sequencing data from 18,787 individual WTC-CRISPRi human induced pluripotent stem cells. We developed an unsupervised clustering method and, through this, identified four subpopulations distinguishable on the basis of their pluripotent state, including a core pluripotent population (48.3%), proliferative (47.8%), early primed for differentiation (2.8%), and late primed for differentiation (1.1%). For each subpopulation, we were able to identify the genes and pathways that define differences in pluripotent cell states. Our method identified four transcriptionally distinct predictor gene sets composed of 165 unique genes that denote the specific pluripotency states; using these sets, we developed a multigenic machine learning prediction method to accurately classify single cells into each of the subpopulations. Compared against a set of established pluripotency markers, our method increases prediction accuracy by 10%, specificity by 20%, and explains a substantially larger proportion of deviance (up to threefold) from the prediction model. Finally, we developed an innovative method to predict cells transitioning between subpopulations and support our conclusions with results from two orthogonal pseudotime trajectory methods.

A simple, affordable diagnostic test for pulmonary tuberculosis (TB) is urgently needed to improve detection of active Mycobacterium tuberculosis.Recently, it has been suggested that animal behavior can be used as a biosensor to signal the presence of human disease. For example, the giant African pouched rats can detect tuberculosis by sniffing sputum specimens while trained honeybees respond to three of the volatile organic compounds (VOCs) detected in the breath of TB positive patients by proboscis extension. However, both rats and honeybees require animal housing facilities and professional trainers, which are outside the scope of most disease testing facilities. Here, we report that the innate olfactory behavioral response of the roundworm nematode Caenorhabditis eleganscan be used to detect the TB-specific VOCs methyl p-anisate, methyl nicotinate, methyl phenylacetate and o-phenylanisole, in chemotaxis assays. Dauer larvae, a long-lived stress resistant alternative development state of C. elegansin which the animals can survive for extended periods of time in dry conditions with no food, were also demonstrated to detect the VOCs. We propose that exposing naive dauer larvae to TB-related VOCs and recording their response in this behavioral assay could lead to the development of a new method for TB diagnostics using breath as the sample type.

Introduction:Bystander CPR is not often performed on OHCA patients, particularly in limited-resource regions. This study aimed to investigate the rate of OHCA patients who did not receive bystander CPR and its impact on the outcomes in an LMIC.Hypothesis:Understanding the reasons bystanders are reluctant to call EMS and how no bystander CPR impacts the outcomes of OHCA patients are crucial for improving survival in Vietnam.Methods:We performed a multicenter prospective cohort study of OHCA patients (≥18 years) presenting to three central hospitals in Vietnam from February 2014 to December 2018. We collected data on characteristics, management, and outcomes and compared these data between patients who did not receive bystander CPR and patients who did. Using logistic regression, we assessed factors associated with survival and good neurological function on discharge (a CPC score of 1 or 2).Results:Of 521 patients, 388 (74.5%) were male, and the mean age was 56.71 years (SD: 17.32). Although most cardiac arrests (68.7%; 358/521) occurred at home and 67.9% (353/520) were witnessed by bystanders, a high rate (77.9%, 406/521) of these patients did not receive bystander CPR. Only half of the patients were taken by EMS (8.1%, 42/521) or private ambulance (42.8%, 223/521); 50.8% (133/262) of whom were given resuscitation attempts by EMS or private ambulance. There was no significant difference in survival to admission (16.7%; 68/406 and 24.3%; 28/115; p=0.064) and survival to discharge (7.9%; 32/406 and 14.8%; 17/115; p=0.094) between patients who did not receive bystander CPR and patients who did. In contrast, the rate of good neurological function of patients who did not receive bystander CPR (4.7%, 19/406) was significantly lower than that of patients who received bystander CPR (12.2%, 14/115; p=0.004). Moreover, multivariate analysis showed that no bystander CPR (OR: 0.276; 95% CI: 0.124-0.614) was inversely and independently associated with good neurological function.Conclusions:In our study, poor outcomes emphasize the need for increasing bystander CPR performance, increasing the number of EMS ambulances and the utilization of private ambulances, and developing a standard emergency first-aid program for both healthcare personnel and the community.

Nanocovax is a recombinant severe acute respiratory syndrome coronavirus 2 subunit vaccine composed of full-length prefusion stabilized recombinant SARS-CoV-2 spike glycoproteins (S-2P) and aluminium hydroxide adjuvant.

The goal of our study was to compare the incidence of motor vehicle accidents (MVA), attempted or completed suicides, and injuries inflicted by others between individuals with and without epilepsy.

Pig oocytes cultured in vitro for 0, 25, 33 and 44h were inseminated by frozen-thawed ejaculated sperm. At specified times after insemination, sperm penetration, cell cycle progression and mitogen-activated protein kinase (MAPK) phosphorylation were evaluated. It was shown that: (1) oocytes at various maturational stages could be penetrated by sperm; (2) sperm penetration did not affect meiotic cell cycle progression; (3) sperm penetration of germinal vesicle (GV) oocytes and maturing oocytes did not alter MAPK phosphorylation; and (4) when premetaphase I (pre-MI) and metaphase I (MI) oocytes, in which MAPK was activated, were fertilised, no evident MAPK dephosphorylation was detected as in metaphase II oocytes. The data suggest that sperm penetration before oocyte maturation does not affect MAPK phosphorylation and that the machinery inactivating MAPK upon fertilisation is not developed in maturing (pre-MI to MI) oocytes.

Introduction:Pre-hospital services are not well developed in Vietnam, especially the immature of a trauma system of care. The prognosis of traumatic out-of-hospital cardiac arrest (OHCA) might differ from that of other countries. This study aimed to investigate the survival rate from traumatic OHCA and to measure the critical components of the chain of survival following a traumatic OHCA in the country.Hypothesis:Although the outcome in cardiac arrest following trauma is dismal, pre-hospital resuscitation efforts are not futile and seem worthwhile. Understanding the country-specific causes, risk, and prognosis of traumatic OHCA is important to reduce mortality in Vietnam.Methods:We performed a multicenter prospective observational study of consecutive patients (>16 years) presenting with traumatic OHCA to 3 central hospitals in Vietnam from February 2014 to December 2018. We collected data on characteristics, management, and outcomes of patients with traumatic OHCA and compared these data between patients who died before hospital discharge and patients who survived to discharge from the hospital.Results:Of 111 eligible patients with traumatic OHCA, 92 (82.9%) were male and the mean age was 39.27 years (standard deviation: 16.38). Only 5.4% (6/111) survived to discharge from the hospital. Most cardiac arrests (62.2%; 69/111) occurred on the street or highway, 31.2% (29/93) were witnessed by bystanders, and 33.7% (32/95) were given cardiopulmonary resuscitation (CPR) by a bystander. Only 26.1% (29/111) of the patients were taken by the emergency medical services (EMS), 90% (27/30) received pre-hospital advanced airway, and 54.7% (29/53) were given resuscitation attempts by EMS or private ambulance. No significant difference between patients who died before hospital discharge and patients who survived to discharge from the hospital was found for bystander CPR (33.7%, 30/89 and 33.3%, 2/6, P>0.999; respectively) and resuscitation attempts (56.3%, 27/48, and 40.0%, 2/5, P=0.649; respectively).Conclusion:Improvements are needed in the EMS in Vietnam, such as increasing bystander first-aid and developing a trauma system of care, as well as developing a standard emergency first-aid program for both healthcare personnel and the community.

Background & Aims: Prostaglandin production in the normal gastrointestinal tract, believed to be critical for mucosal integrity, is mediated by cyclooxygenase (COX)-1, whereas prostaglandin production at inflammatory sites seems to occur via induction of COX-2. We hypothesized that COX-2-specific inhibition with rofecoxib (25 mg once daily) in the treatment of patients with osteoarthritis would cause fewer gastroduodenal ulcers than an equally effective dose of ibuprofen (800 mg 3 times a day), a nonspecific COX inhibitor. Methods: A total of 742 osteoarthritis patients without ulcers on baseline endoscopy were randomly assigned to receive rofecoxib (25 or 50 mg once daily), ibuprofen (800 mg 3 times daily), or placebo. Endoscopy was repeated at 6, 12, and 24 weeks. At 16 weeks, by study design, 95% of the placebo group and 5% of the other groups were discontinued. Results: The cumulative incidence of gastroduodenal ulcers >=3 mm with rofecoxib (25 or 50 mg once daily) was significantly (P < 0.001) lower than with ibuprofen and was statistically equivalent to placebo at week 12 (placebo, 9.9%; 25 mg rofecoxib, 4.1%; 50 mg rofecoxib, 7.3%; and ibuprofen, 27.7%). At 24 weeks, ulcer rates were 25 mg rofecoxib, 9.6%; 50 mg rofecoxib, 14.7%; and ibuprofen, 45.8% (P < 0.001, ibuprofen vs. 25 and 50 mg rofecoxib). Conclusions: Rofecoxib, at doses 2-4 times the dose demonstrated to relieve symptoms of osteoarthritis, caused significantly less gastroduodenal ulceration than ibuprofen, with ulcer rates comparable to placebo. GASTROENTEROLOGY 1999;117:776-783

Abstract: The desorption behaviour (desorption temperature and extent of desorption) of HF,HCFC-133a (CF3CH2Cl) and HFC-134a (CF3CH2F) on γ-AlF3 or catalyst supported on γ-AlF3 was studied using an adsorption apparatus and TG, DTA and DSC methods. On the basis of the results a reaction mechanism was proposed for the preparation of HFC-134a. The γ-AlF3 employed for preparing the catalyst was expected to be stable below 550C based on the crystalline phase transition temperature of γ-AlF3.

The problem is addressed of assessing realistic confidence limits for oncogenic transformation rates when the incidence of transformation is small, and there is a background present. It is shown that the commonly used approximations for assessing the confidence interval on the radiation-induced transformation rate (t1) and the control rate (t2) are inadequate when only a small number of transformants are observed. Accurate techniques are described for these cases for the estimation of confidence limits of t1, t2 and also t1 - t2.

Immunohistochemistry and flow cytometry analyses were performed to characterize the specific T cell subpopulations infiltrating basal cell carcinomas (BCC) and to determine their phenotypic response to in vitroexpansion with IL-2. Tumor-infiltrating lymphocytes (TIL) within BCC predominantly expressed the CD45RO (activated or "memory") phenotype (65 ± 3%) and the percentage of TIL expressing CD45RO consistently increased when cultured in vitrowith IL-2 (85 ± 5%). In comparison, fresh normal peripheral blood lymphocytes predominantly expressed the CD45RA (naive) phenotype (79 ± 4%), but shifted to the expression of CD45RO following in vitroexpansion in IL-2 (86 ± 6%). To determine whether IL-2 alone, in the absence of antigen or mitogen, can promote naive lymphocytes to convert from the expression of the CD45RA isoform to the CD45RO isoform, we cultured purified CD45RA + lymphocytes in IL-2. After three weeks in culture, 90% of the lymphocytes expressed exclusively CD45RO. We conclude that tumor-infiltrating lymphocytes from BCC predominantly express CD45RO and that this expression may represent specific antigen stimulation and/or in situactivation by cytokines.

Helicobacter pylori is involved in gastritis, gastric and duodenal ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. Earlier studies already suggested a role for autoimmune phenomena in H. pylori-linked disease. We now report that lipopolysaccharides (LPS) of H. pylori express Lewis y, Lewis x, and H type I blood group structures similar to those commonly occurring in gastric mucosa. Immunization of mice and rabbits with H. pylori cells or purified LPS induced an anti-Lewis x or y or anti-H type I response, yielding antibodies that bound human and murine gastric glandular tissue, granulocytes, adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma cells. Experimental oral infections in mice or natural infection in humans yielded anti-Lewis antibodies also. The beta chain of gastric (H+,K+)-ATPase, the parietal cell proton pump involved in acid secretion, contained Lewis y epitopes; gastric mucin contained Lewis x and y antigenic determinants. Growth in mice of a hybridoma that secretes H. pylori-induced anti-Lewis y monoclonal antibodies resulted in histopathological evidence of gastritis, which indicates a direct pathogenic role for anti-Lewis antibodies. In conclusion, our observations demonstrate that molecular mimicry between H. pylori LPS and the host, based on Lewis antigens, and provide understanding of an autoimmune mechanism for H. pylori-associated type B gastritis.

It has long been known that there is a problem with the results of ‘conventional’ (as epitomized in the Biometrika Tables for Statisticians) techniques for calculating confidence limits for parameters of discrete distributions. Specifically, the calculated limits at a given confidence level are always much too wide, i.e. overly conservative. For large sample sizes (n≥ 100) this is not important, but for small samples, the conventional techniques can be very conservative. In this note, exact confidence limits for the parameter p, as calculated in binomial sampling, are presented. A Bayesian technique is used, and the results are presented for the situation where no prior information is assumed, corresponding to the ‘conventional’ scenario for confidence‐limit estimation. Our results are compared quantitatively with those in the Biometrika Tables by use of Monte‐Carlo simulation. The results show, as expected, that for small sample sizes, the Biometrika Tables yield confidence intervals that are considerably too wide, and that our approach does indeed produce exact confidence limits. Extensive graphs of results are presented.

The e.m.f. of the galvanic cell Sn/Sn(II)//Cr(II), Cr(III)/C changes sign between 25–95° C. Its possibilities for electrochemical conversion of thermal energy have been considered. The redox potentials of the systems Sn/Sn(II) and Cr(II)/Cr(III) have been determined as a function of the temperature and the concentration of chloride ions. By choosing the appropriate CaCl2 concentration the inversion may be made to occur at any temperature. The temperature coefficient of the cell has been found to be 1·42 mV/° C. An experimental cell has been designed and the causes of the phenomenon are discussed.