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As of March 30, 2020, approximately 750,000 cases of coronavirus disease (COVID-19) had been reported globally since December 2019 (1), severely burdening the healthcare system (2). The extremely fast transmission [...]

Quantum interference (QI) has been identified as a promising strategy for designing molecular-scale electronic devices. Heteroatom doping can effectively tailor the local structures and electronic states of intrinsic molecules, and endow them with modified electron transport properties. Herein, the impacts of multiple heteroatom substitution on destructive quantum interference (DQI) have been investigated based on tripodal meta-linked phenyl derivatives. Orbital views based on the Hückel method qualitatively predict the meta-anchored molecules with DQI features, while the introduction of nitrogen atoms can alleviate the suppression of DQI at the Fermi level (EF). This is generally consistent with the movement or even removal of the antiresonance dips in transmission spectra. The substituent on position 2 can raise the antiresonance energy, while the substituent on position 4 or 6 can lower the antiresonance energy. When more than one nitrogen atom is incorporated, the impact of the substitution on positions 4 and 6 can be superimposed and the substitution on positions 2 and 4 can be partly cancelled. The experimental single-molecule conductance for tripodal molecules follows the trend of 0N-3SMe < 1N-3SMe < 3N-3SMe < 2N-3SMe, in agreement with the theoretical prediction. Additionally, the regulation is the intrinsic property depending on the position and number of the nitrogen atoms in the backbone and is irrelevant to the number and type of the anchoring groups. Our findings provide qualitative guidance for tuning the electron transport based on DQI in heterocycle molecular devices. [ABSTRACT FROM AUTHOR]

A nickel-catalyzed strategy for the synthesis of 1,3-diaryl-6H-pyrazino[2,1-b]quinazolin-6-one was developed. This method enabled us to access valuable pyrazino-fused quinazolinones with tolerance of many functional groups even at room temperature. The desired pyrazino-fused quinazolinones emit strongly in both solution and solid states. Furthermore, the thermally-activated delayed fluorescence (TADF) of 3a was investigated. This study provides an efficient synthetic route for the development of TADF-active pyrazino-fused quinazolinones, thus expanding the application range of this versatile molecular scaffold in optoelectronics. [ABSTRACT FROM AUTHOR]

Combining quantum-tunneling-effect-enabled hopping theory with kinetic Monte Carlo simulation and dynamic disorder effects, the charge transport properties of a series of N-hetero 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) derivatives with halogen substitutions were studied. Based on the single molecule and the theoretically predicted crystal structure, the electronic structures and nuclear dynamic disorder effects of halogen and aza systems and their impacts on the charge transport behaviors were expounded. On the one hand, this study revealed the regularity of carrier transport by substitution with one or two pyrazine rings from the external toward the internal for benzene rings in TIPS-PEN, suggesting the substitution of two internal pyrazine rings can sharply shrink the hole transport features. Meanwhile, internal pyrazine rings improve the electron transport performance mainly by enhancing air stability and compacting π-stacking. On the other hand, the investigation elaborated the delicate tuning effect of chlorination on two kinds of carrier transports based on aza-TIPS-PEN derivatives, indicating chlorination can effectively equilibrate the electron and hole reorganization energies and decrease the slip distances along the molecular long and short axes in favor of the similarity in the hole and electron transfer integral values, thereby yielding increasingly balanced ambipolar transport characteristic. The coordination of monopyrazine substitution and chlorination on the acene is an effective way to acquire ambipolar transport properties. In addition, the nuclear dynamic disorder effect affects the hole transfer integral more than the electron transfer integral. In the case of the comprehensive consideration of both ease of charge injection and intrinsic transport mobility, both 8,9,10,11-tetrafluoro-6,13-bis((triisopropylsilyl)ethynyl)naphtho[2,3-b]phenazine (2b) and tetrachloro-6,13-bis((triisopropylsilyl)ethynyl)quinoxalino[2,3-b]phenazine (3c) exhibited to be electron-dominant materials, while 8,9,10,11-tetrachloro-6,13-bis((triisopropylsilyl)ethynyl)naphtho[2,3-b]phenazine (2c) showed effective ambipolar transport characteristics with average hole/electron mobility of 3.64/2.21 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

It is very important to analyse the most advantageous connection style for quinoidal thiophene derivatives, which are used in n-type organic semiconductor transport materials. In the present work, the charge transport properties of three series of quinoidal thiophene derivatives, oligothiophene (series A), thienothiophene (series B) and benzothiophene (series C), are systematically investigated by employing full quantum charge transfer theory combined with kinetic Monte-Carlo simulation. The single crystal structures of the molecules we had constructed were predicted using the USPEX program combined with density functional theory (DFT) and considering the dispersion corrected. Our theoretical results expounded how the different connection styles, including oligo-, thieno-, and benzo-thiophene in the quinoidal thiophenes derivatives, effectively tune their electronic structures, and revealed how their intermolecular interactions affect the molecular packing patterns and hence their charge transport properties by symmetry-adapted perturbation theory (SAPT). In the meantime we also elucidated the role of end-cyano groups in noncovalent interactions. Furthermore, it is clarified that quinoidal thiophene derivatives show excellent carrier transport properties due to their optimal molecular stacking motifs and larger electronic couplings besides their low energy gap. In addition, our theoretical results demonstrate that quinoidal oligothiophene derivatives (n = 3–5) with more thiophene rings will have ambipolar transport properties, so quinoidal thienothiophene and benzothiophene derivatives should be promising alternatives as n-type OSCs. When we focused only on the electronic transport properties in the three series of molecules, quinoidal benzothiophene derivatives were slightly better than quinoidal oligothiophene or thienothiophene derivatives. [ABSTRACT FROM AUTHOR]

Chinese ferret badger (FB)-transmitted rabies is a serious threat to public health in southeast China. Although mostly associated with dogs, the rabies virus (RABV) presents genetic diversity and has a significantly wide host range in China. Instead of the dog- and wildlife-associated China II lineage in the past decades, the China I lineage has become the main epidemic group hosted and transmitted by dogs. In this study, four new lineages, including 43 RABVs from FBs, have been classified within the dog-dominated China I lineage since 2014. FB RABVs have been previously categorized in the China II lineage. Moreover, FB-hosted viruses seem to have become the main independent FB-associated clade in the phylogenetic tree. This claim suggests that the increasing genetic diversity of RABVs in FBs is a result of the selective pressure from coexisting dog rabies. FB transmission has become complicated and serious with the coexistence of dog rabies. Therefore, apart from targeting FB rabies, priority should be provided by the appropriate state agencies to perform mass immunization of dog against rabies. [ABSTRACT FROM AUTHOR]

2,5-Difluoro-7,7,8,8-tetracyanoquinodimethane (F2-TCNQ) was recently reported to display excellent electron transport properties in single crystal field-effect transistors (FETs). Its carrier mobility can reach 25 cm2 V−1 s−1 in devices. However, its counterparts TCNQ and F4-TCNQ (tetrafluoro-7,7,8,8-tetracyanoquinodimethane) do not exhibit the same highly efficient behavior. To better understand this significant difference in charge carrier mobility, a multiscale approach combining semiclassical Marcus hopping theory, a quantum nuclear enabled hopping model and molecular dynamics simulations was performed to assess the electron mobilities of the Fn-TCNQ (n = 0, 2, 4) systems in this work. The results indicated that the outstanding electron transport behavior of F2-TCNQ arises from its effective 3D charge carrier percolation network due to its special packing motif and the nuclear tunneling effect. Moreover, the poor transport properties of TCNQ and F4-TCNQ stem from their invalid packing and strong thermal disorder. It was found that Marcus theory underestimated the mobilities for all the systems, while the quantum model with the nuclear tunneling effect provided reasonable results compared to experiments. Moreover, the band-like transport behavior of F2-TCNQ was well described by the quantum nuclear enabled hopping model. In addition, quantum theory of atoms in molecules (QTAIM) analysis and symmetry-adapted perturbation theory (SAPT) were used to characterize the intermolecular interactions in TCNQ, F2-TCNQ and F4-TCNQ crystals. A primary understanding of various noncovalent interaction responses for crystal formation is crucial to understand the structure–property relationships in organic molecular materials. [ABSTRACT FROM AUTHOR]

Rabies is a neglected zoonotic disease that is preventable in humans by appropriate post-exposure prophylaxis (PEP). However, current PEP relies on polyclonal immune globulin products purified from pooled human (HRIG) or equine (ERIG) plasma that are either in chronic shortage or in association with safety concerns. Here, we present the development of an antibody cocktail, SYN023, made of two novel monoclonal antibodies (MAb) CTB011 and CTB012 that could serve as safer and more cost-effective alternatives to the current RIG products. Both CTB011 and CTB012 are humanized MAbs that bind to non-overlapping epitopes on the rabies virus (RABV) glycoprotein (G) with sub-nanomolar affinities. Sequence analysis revealed that many of the critical residues in binding are highly conserved across different species of lyssaviruses. When combined at a 1:1 ratio, CTB011/CTB012 exhibited neutralization capabilities equivalent or superior to HRIG against 10 North American street RABV isolates in vitro and 15 prevalent Chinese RABV strains in animal models. Finally, SYN023, at a dosage of 0.03 mg/kg, was able to offer the same degree of protection as standard HRIG administration (20 IU/kg) in Syrian hamsters challenged with a highly virulent bat (Tadarida brasiliensis) RABV variant. Taken together, the high-potency and broad-spectrum neutralization demonstrated by SYN023 make it an effective candidate for human rabies PEP consideration. [ABSTRACT FROM AUTHOR]

Rabies remains a continuous threat to public health in Beijing. In this study, a total of 224 brain tissues were collected from suspected infected stray dogs within Beijing between January 2015 and December 2016. Among them, total of 67 samples were diagnosed positive for rabies. In the phylogenetic analysis, rabies in Beijing is currently a relatively independent public health issue originating from local rabid dogs apart from the imported cases from elsewhere in the country. Because vaccination of unregistered dogs against rabies is still neglected in Beijing and other regions of China, national and local authorities should play central roles in all related aspects, such as development of policies, engagement of stakeholders for public and professional education, entire vaccination process, and animal management. [ABSTRACT FROM AUTHOR]

A theoretical study was carried out to investigate the electronic structures and the charge transport properties of a series of naphthodithiophene diimide (NDTI) thiophene α-substituted derivatives NDTI-X using density functional theory and classical Marcus charge transfer theory. This study deeply revealed the structure–property relationships by analyzing the intermolecular interactions in crystal structures of C8-NDTI and C8-NDTI-Cl thoroughly by using the Hirshfeld surface, QTAIM theories and symmetry-adapted perturbation theory (SAPT). Our results suggested that a 2-D brick-like π-stacking structure makes C8-NDTI-Cl a more excellent n-type semiconducting material with μmax-e of 2.554 cm2 V−1 s−1 than C8-NDTI with a herringbone-like slipped π-stacking motif. In addition, the calculated results showed that by modifying the thiophene α-positions of NDTI with electron-withdrawing substituents, –F, –Cl and –CN, low-lying LUMO energy levels and a high adiabatic electron affinity EA(a) can be obtained; while introducing electron-donating groups, benzene (–B), thiophene (–T), benzo[b]thiophene (–BT) and naphtha[2,3-b]thiophene (–NT), expanded the molecular π-conjugated backbone, and narrow band gaps, high EA(a) and small reorganization energies can be obtained. Theoretical simulations predict that NDTI-CN is an excellent air-stable n-type organic semiconducting material with an average electron mobility μe of up to 1.743 cm2 V−1 s−1. Owing to their high EA(a), moderate adiabatic ionization potential IP(a) as well as small hole and electron reorganization energies, NDTI-BT and NDTI-NT are two well-balanced air-stable ambipolar semiconducting materials. The theoretical average hole/electron mobilities are as high as 2.708/3.739 cm2 V−1 s−1 for C8-NDTI-NT and 1.597/2.350 cm2 V−1 s−1 for C8-NDTI-BT, respectively. [ABSTRACT FROM AUTHOR]

In contrast to many countries where rabies has been well controlled in humans and livestock, even in wildlife, rabies is still endemic in almost regions of China. In Northwest China, rabies transmitted by stray dogs and wild foxes has caused heavy economic losses to local herdsmen, as well as causing numbers of human cases. In this study, as part of an investigation of ways to prevent rabies epidemics in livestock, we report an analysis of domestic cattle and camel rabies cases in Ningxia Hui (NHAR) and Inner Mongolia Autonomous Region (IMAR) and the immune efficacy of canine inactivated rabies vaccines in these animals. We found that rabies viruses from these animals are closely related to dog-hosted China I and fox-associated China III lineages, respectively, indicating that the infections originated from two different sources (dogs and wild foxes). As well as the previously reported Arctic and Arctic-related China IV lineage in IMAR, at least three separate phylogenetic groups of rabies virus consistently exist and spread throughout Northwest China. Since there is no licensed oral vaccine for wild foxes and no inactivated vaccine for large livestock, local canine inactivated vaccine products were used for emergency immunization of beef and milk cattle and bactrian (two-humped) camels in local farms. Compared with a single injection with one (low-efficacy) or three doses (high-cost), a single injection of a double dose of canine vaccine provided low-price and convenience for local veterinarians while inducing levels of virus neutralizing antibodies indicative of protection against rabies for at least 1 year in the cattle and camels. However, licensed vaccines for wildlife and large domestic animals are still needed in China. [ABSTRACT FROM AUTHOR]

Lyssaviruses, including Rabies virus, Duvenhage virus, European bat lyssavirus 1, European bat lyssavirus 2, Australian bat lyssavirus, and Irkut virus (IRKV), have caused human fatalities, but infection of IRKV in dogs has not been previously reported. In China, a dead dog that previously bit a human was determined to be infected with IRKV. Pathogenicity tests revealed that IRKVs can cause rabies-like disease in dogs and cats after laboratory infection. The close relationship between humans and pets, such as dogs and cats, may generate a new spillover-spreading route for IRKV infection. Therefore, additional attention should be paid to trans-species infection of IRKV between bats and dogs or dogs and humans through investigation of the prevalence and circulation patterns of IRKV in China. [ABSTRACT FROM AUTHOR]

The article presents a study of the use of multiple reverse transcriptase polymerase chain reaction (RT-PCR) assay to analyze the five viruses including the peste des petits ruminants virus N protein gene (PPRV), Hendra virus H protein gene (HeV), and West Nile fever virus PrM protein gene (WNV). It performs a retrospective study of 101 frozen samples, which include 45 swine samples and 56 bat samples. It says that PCR gave positive results for positive control, but not for other samples.

Human rabies is a serious public health problem that can't be ignored. Rabies immune globulin (RIG) is an indispensable component of rabies post-exposure prophylaxis (PEP). However, current PEP relies on RIG purified from pooled human or equine plasma, which are either in chronic shortage or associated with safety concerns. Monoclonal antibodies have become widely accepted as safer and more cost-effective alternatives to RIG products in recent years. Here, we assessed the neutralization breadth of human monoclonal antibody ormutivimab and its protective efficacy in PEP models. Ormutivimab was able to neutralize a broad panel of Chinese prevalent street RABVs with neutralizing potency form 198–1487.6 IU/mL. Furthermore, ormutivimab offered comparable protection to that with HRIG both at standard doses (20 IU/kg) and higher doses (100 IU/kg and 200 IU/kg). The interference of ormutivimab on vaccine potency was also analyzed and found slightly reduced neutralizing antibody titers similar to HRIG. The broad-spectrum neutralization activities, highly protective potency, and rapid onset of action make ormutivimab an effective candidate for human rabies PEP. [ABSTRACT FROM AUTHOR]

The article presents information on a study related to the use of nested reverse transcriptase polymerase chain reaction (RT-PCR) for detection of nucleic acid of rabies virus genotype 1. It informs that in the study a set of primers was designed for nested RT-PCR for the detection of rabies virus from multiple samples. It further informs that RT-PCR proved to be fully reaction to a panel of isolates from humans, dogs, sheep, deer and ferret badgers.

The article explores the isolation of a feline calicivirus from the saliva of a cat during epidemiological study of its rabies. It was found to be a naturally attenuated virus through a series of systematic identification such as morphological test, physicochemical test, and in vivo infection. A high level of antibody against the virus is induced after subcutaneous or oral inoculation. The antibody was found to persist for at least 50 weeks.

The article discusses a study on the construction of recombinant retroviral vector of antimicrobial peptide genes and expression in mammary gland in the post partum cow.

The article discusses a study on the construction of recombinant pseudorabies virus (TK-/gI-) norientation expressing glycoprotein of rabies virus using the AseI/Mlu I restriction enzymes.

The article presents a study which discusses the construction of recombinant pseudorabies virus norientation expressing glycoprotein of rabies virus (8202 strain).

Quantum-chemistry methods are used to investigate the effect of phenylamine chromophore on the electronic structure, optical properties, and phosphorescence efficiencies of a series of fac -iridium(III) complexes, Ir-(g0) 3 (1) , meta-substituted Ir compounds [Ir-(g0) 2 -(g1) 1 ] (1a) , [Ir-(g0) 1 -(g1) 2 ] (1b) , [Ir-(g1) 3 ] (1c) and para-substituted Ir compounds [Ir-(g0) 2 -(g1′) 1 ] (2a) , [Ir-(g0) 1 -(g1′) 2 ] (2b) , [Ir-(g1′) 3 ] (2c) , where g0 = l -phenylisoquinolinato, g1 = 4-(isoquinolin-1-yl)- N , N -diphenylbenzenamine, g1′ = 3-(isoquinolin-1-yl)- N , N -diphenylbenzenamine. The calculations show that introduction of phenylamine chromophore at meta position of phenyl ring ( 1a – 1c ) slightly changes the ground-states geometries but largely increases the energy of HOMO and decreases IP values hence improves the ability of hole injection, which is consistent with the experimental report. The introduction of diphenylamine substitutions on the para position ( 2a – 2c ) is effective for extending the π-electron delocalization, which results in strengthening metal-ligand bond and dramatically increasing the HOMO energy. More important, the 2a – 2c have enhanced metal-to-ligand charge transfer 3 MLCT participation in the phosphorescent spectra, decreased the singlet-triplet splitting energy (Δ E S1–T1 ), as well as dramatically small energy differences between the highest occupied orbitals splitting (Δdd occ ) and large lowest unoccupied d-orbitals splitting (Δdd*) at the both S 0 and T 1 geometries, these account for the quantum yield and efficiency of phosphorescence. The calculated ionization potentials (IPs), electronic affinities (EAs), and reorganization energy ( λ ) confirm that the hole and electron injection and transfer ability were enhanced by importing the diphenylamine. Furthermore, based on the analyses of triple energy differences between host and guest, charge carrier mobility, optical overlap, it is found that these Ir complexes maybe good guest materials in CBP. Thus, the introduction of phenylamine at para position is effective approach to obtain highly efficient red phosphorescent emitters. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an obligate intracellular apicomplexan parasite which is able to infect almost all warm-blooded animals. There is no information about the prevalence and genetic characterization of T. gondii in badgers ( Melogale moschata ) in China. Here, a total of 367 badgers were captured from different cities in Jiangxi province, Southern China. Genomic DNA was extracted from brain tissues of each badgers, and 57 (15.45%) of them were positive for T. gondii by semi-nested PCR of the B1 gene. The positive DNA samples were typed at 11 genetic markers, including 10 nuclear loci (SAG1, 5′-SAG2 and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1) and an apicoplast locus (Apico), with multilocus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Among them, 4 were completely typed at all loci, and 2 was genotyped for 9 loci, showing that they belong to ToxoDB#9. This is the first report of prevalence and genetic characterization of T. gondii isolates from badgers in China, which contributes to broader understanding of population structure of T. gondii in China. It is important for the prevention and control of T. gondii infection in wild animals. [ABSTRACT FROM AUTHOR]