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NGC 300 ULX1 is a pulsating ultraluminous X-ray source (PULX) with the longest spin period of |$P\simeq 31.6\, \rm s$| and a high spin-up rate of |$\dot{P}\simeq -5.56\times 10^{-7}\, \rm s\, s^{-1}$| that is ever seen in the confirmed PULXs. In this paper, the inferred magnetic field of NGC 300 ULX1 is |$\sim 3.0\times 10^{14}\, \rm G$| using the recent observed parameters after its first detection of pulsations. According to the evolved simulation of the magnetic field and the spin period, it will become a recycled pulsar or a millisecond pulsar under the conditions of the companion mass and the accretion rate limitation. We suggest that NGC 300 ULX1 is an accreting magnetar accounting for its super Eddington luminosity. We also propose that there might be other accreting magnetars in the confirmed PULXs. Such PULXs will be helpful for understanding the magnetar evolution and the millisecond pulsar formation whose magnetic field is stronger than |$\sim 10^{9}\, \rm G$|⁠. [ABSTRACT FROM AUTHOR]

Charge exchange has been recognized as a primary source of soft X-ray emission in many astrophysical outflow environments, including cometary and planetary exospheres impacted by the solar wind. Some models have been set up by using different data collections of charge-exchange cross-sections. However, multiple-electron transfer has not been included in these models. In this paper, we set up a charge-exchange model with the inclusion of double-electron capture (DEC), and make a detailed investigation of this process on X-ray emissions of highly charged carbon, nitrogen, oxygen, and neon ions by using available experimental cross-sections. We also study the effect of different n- selective cross-sections on soft X-ray emission by using available experimental n -distributions. This work reveals that DEC enhancement on line intensity is linearly proportional to the ratio of ion abundance in the solar wind. It is more obvious for soft X-rays from carbon ions (C4+) in collision with CO2, and the enhancement on line intensity can be up to 53 per cent with typical ion abundances [ Advanced Composition Explorer (ACE)] in the solar wind. The synthetic spectra with parameters from the Ulysses mission for the solar wind reveal velocity dependence, target dependence, as well as the non-negligible contribution from the DEC. [ABSTRACT FROM AUTHOR]

Aims: To study the antimicrobial agents of the Bacillus velezensis strain HC6 and assess the application potential of B. velezensis HC6 in maize. Methods and Results: We applied a dual culture technique to test the antimicrobial activity of B. velezensis HC6 against bacteria and fungi of common contaminated crops. Bacillus velezensis HC6 showed antagonistic action on pathogenic fungi, including Aspergillus and Fusarium, as well as pathogenic bacteria (especially Listeria monocytogenes). When applied in maize, B. velezensis HC6 could also inhibit the growth of multiple pathogenic fungi and reduce their production of aflatoxin and ochratoxin. Three kinds of antimicrobial lipopeptides, including iturin, fengycin and surfactin were identified in B. velezensis HC6 culture supernatant by high‐performance liquid chromatography and MALDI‐TOF mass spectrometry. Iturin and fengycin showed obvious antimicrobial activity to the tested fungal strains. Conclusions: Bacillus velezensis HC6 produces three kinds of lipopeptides which showed antimicrobial activity against several common pathogenic fungi and bacteria. Bacillus velezensis HC6 is potential to be biocontrol bacteria in maize. Significance and Impact of the Study: Bacillus velezensis HC6 shows obvious antimicrobial activity to important crops pathogenic fungi which usually produce mycotoxins that are harmful to animal and human health. We demonstrate that three different types of lipopeptides produced by B. velezensis contributed to the antimicrobial activity. Bacillus velezensis HC6 has the potential to be effective biocontrol agent in crops. [ABSTRACT FROM AUTHOR]

Objective: To establish the provision and use of radiation personal protective equipment (PPE) and dosimetry amongst UK interventional radiology (IR) trainees and highlight areas of improvement in order to enhance the radiation safety. Methods: A survey questionnaire was designed by members of the British Society of Interventional Radiology (BSIR) trainee committee via survey monkey and distributed to UK IR trainees via the BSIR membership mailing list, local representatives and Twitter. The survey was open from 04/01/2021 to 20/02/2021. Only IR trainees in years ST4 and above were included. Results: Of the 73 respondents, 62 qualified for analysis. Respondents (81% male) spent a median of 5.5 sessions (half day list) per week in the angiography suite and 58% (n=36) had difficulty finding appropriately sized lead aprons at least once a week. Overall 53% (n=33) had concerns about their radiation PPE. Furthermore 56% of trainees (n=35) experienced back pain among other symptoms attributed to wearing the lead aprons available to them. 77% (n=48) regularly wore lead glasses. For trainees requiring prescription glasses (n=22) overfit goggles were provided however 17 (77%) of these trainees felt the goggles compromised their ability to perform the procedure. Eye and finger dosimeters were used by 50% and 52% of respondents respectively. Compliance with body dosimetry was 99%. Conclusion: Provision of radiation PPE and dose monitoring for IR trainees is suboptimal, particularly access to adequate eye protection or suitably fitting leads. Based on the findings of this survey, recommendations have been made to promote the safety and radiation awareness of IR trainees. Advances in knowledge: Radiation protection practices for IR trainees nationally are poor. Provision of suitable eye protection and well fitting lead body protection is low. [ABSTRACT FROM AUTHOR]

Bacillus subtilis ZK0, which was isolated from cotton, produces a type of lipopeptide antibiotic iturin A that inhibits the growth of pathogenic fungi on agricultural crops. However, the low level of iturin A production by B. subtilis ZK0 does not support its large-scale application. In this study, B. subtilis ZK0 was subjected to genetic manipulation to improve iturin A production. By the independent or simultaneous overexpression of two regulatory genes ( comA and sigA), iturin A production by B. subtilis ZK0 was significantly increased. When both genes were simultaneously overexpressed under optimal conditions, iturin A production increased up to 215 mg l−1 (an approximate 43-fold increase compared with B. subtilis ZK0). Moreover, overexpression of both genes was unexpectedly found to inhibit biofilm formation by B. subtilis ZK0, indicating that the phenomenon of 'stuck fermentation' would be avoided during B. subtilis ZK0 fermentation. In conclusion, a genetic manipulation method that improves iturin A production and inhibits biofilm formation in B. subtilis ZK0 is reported for the first time and this method has the potential to be widely applied in B. subtilis ZK0 commercial fermentation. Significance and Impact of the Study This study provides new perspectives on improving iturin A production by Bacillus subtilis. Our newly engineered strains could be applied to commercial fermentation by enhancing yields of iturin A and reducing the rate of 'stuck fermentation'. Increased production would facilitate more widespread application of this powerful antibiotic. [ABSTRACT FROM AUTHOR]

Although it is generally accepted that the unidentified infrared emission (UIE) features at 3.3, 6.2, 7.7, 8.6, and 11.3 µm are characteristic of the stretching and bending vibrations of aromatic hydrocarbon materials, the exact nature of their carriers remains unknown: whether they are free-flying, predominantly aromatic gas-phase molecules, or amorphous solids with a mixed aromatic/aliphatic composition are being debated. Recently, the 3.3 and 3.4 µmfeatures which are commonly respectively attributed to aromatic and aliphatic C-H stretches have been used to place an upper limit of ~2 per cent on the aliphatic fraction of the UIE carriers (i.e. the number of C atoms in aliphatic chains to that in aromatic rings). Here we further explore the aliphatic versus aromatic content of the UIE carriers by examining the ratio of the observed intensity of the 6.2 µm aromatic C-C feature (I6.2) to that of the 6.85 µm aliphatic C-H deformation feature (I6.85). To derive the intrinsic oscillator strengths of the 6.2 µm stretch (A6.2) and the 6.85 µm deformation (A6.85), we employ density functional theory to compute the vibrational spectra of seven methylated polycyclic aromatic hydrocarbon molecules and their cations. By comparing I6.85/I6.2 with A6.85/A6.2, we derive the fraction of C atoms in methyl(ene) aliphatic form to be at most ~10 per cent, confirming the earlier finding that the UIE emitters are predominantly aromatic. We have also computed the intrinsic strength of the 7.25 µm feature (A7.25), another aliphatic C-H deformation band. We find that A6.85 appreciably exceeds A7.25. This explains why the 6.85 µm feature is more frequently detected in space than the 7.25 µm feature. [ABSTRACT FROM AUTHOR]

Background Liver resection for intermediate (Barcelona Clinic Liver Cancer ( BCLC) stage B) hepatocellular carcinoma ( HCC) remains controversial. This study attempted to demonstrate the effectiveness of preresection transarterial chemoembolization ( TACE) as a selection criterion for BCLC-B HCC. Methods The study included patients with BCLC-B HCC who underwent liver resection after TACE. The tumour response to TACE was evaluated according to the modified Response Evaluation Criteria in Solid Tumours ( mRECIST). Patients with a complete or partial response comprised the responder group, whereas those with stable or progressive disease were classified as non-responders. Results A total of 242 patients were included. After between one and eight sessions of TACE, 141 patients were included in the responder group: 37 patients (15·3 per cent) who achieved a complete response and 104 who had a partial response. The cumulative 1-, 3- and 5-year overall survival rates were 97·2, 88·7 and 75·2 per cent respectively in the responder group, compared with 90·1, 67·3 and 53·5 per cent among 101 non-responders ( P < 0·001). Tumour-free survival rates were also better among responders than non-responders ( P < 0·001). In multivariable analysis, independent predictors of overall and tumour-free survival were response to TACE and microvascular invasion (all P < 0·001). Conclusion mRECIST may represent selection criterion for intermediate HCC for surgical treatment. [ABSTRACT FROM AUTHOR]

Background The Child-Pugh ( CP) score is used widely to assess liver function and predict postoperative outcomes in patients with hepatocellular carcinoma ( HCC). Recently, the albumin-bilirubin ( ALBI) score has been validated as a predictor of overall survival in these patients. This study aimed to compare the ability of the ALBI and CP scores to predict outcomes in patients with HCC after liver resection with curative intent. Methods Consecutive patients who underwent liver resection with curative intent for HCC between January 2007 and July 2013 were included in this retrospective study. The performance of the ALBI score in predicting postoperative liver failure ( PHLF) and long-term survival was compared with that of the CP score. Results A total of 1242 patients were enrolled. Of these, 166 (13·4 per cent) experienced PHLF. The area under the receiver operating characteristic ( ROC) curve of the ALBI score for predicting PHLF was greater than that of the CP score (0·723 versus 0·607; P < 0·001). Similar to findings for CP grade, the incidence and severity of PHLF increased with increasing ALBI grade. The ALBI grade stratified patients into at least two distinct overall survival cohorts ( P < 0·001), whereas the CP grade did not. The ALBI grade also classified patients with CP grade A disease into two distinct overall survival cohorts ( P < 0·001), and overall survival rates in the group with poorer survival were similar to those in the majority of patients with CP grade B disease. Both CP and ALBI scores had low power in predicting disease-free survival. Conclusion The ALBI grade predicted PHLF and overall survival in patients with HCC undergoing liver resection with curative intent more accurately than the CP grade. [ABSTRACT FROM AUTHOR]

Locating ultracool companions to M dwarfs is important for constraining low-mass formation models, the measurement of substellar dynamical masses and radii, and for testing ultracool evolutionary models. We present an optimized method for identifying M dwarfs which may have unresolved ultracool companions. We construct a catalogue of 440 694 M dwarf candidates, from Wide-Field Infrared Survey Explorer, Two Micron All-Sky Survey and Sloan Digital Sky Survey, based on optical- and near-infrared colours and reduced proper motion. With strict reddening, photometric and quality constraints we isolate a subsample of 36 898 M dwarfs and search for possible mid-infrared M dwarf + ultracool dwarf candidates by comparing M dwarfs which have similar optical/near-infrared colours (chosen for their sensitivity to effective temperature and metallicity). We present 1082 M dwarf + ultracool dwarf candidates for follow-up. Using simulated ultracool dwarf companions to M dwarfs, we estimate that the occurrence of unresolved ultracool companions amongst our M dwarf + ultracool dwarf candidates should be at least four times the average for our full M dwarf catalogue. We discuss possible contamination and bias and predict yields of candidates based on our simulations. [ABSTRACT FROM AUTHOR]

Optimal treatment of esophageal small-cell cancer, a rare disease, lacks consensus. Based on its lung small-cell cancer analog, we hypothesized that chemotherapy with adjuvant radiotherapy would be optimal. This hypothesis was tested by studying the collective published literature. A meta-analysis of individual patients from 148 articles (1952-2010) explored treatment and outcome of 577 patients with esophageal small-cell cancer. Hazard function frailty modeling identified optimum therapy after accounting for article-level and patient-level heterogeneity. Fifty-nine percent of publications reported one patient and 25% five or more. Sixty-six percent of patients were men, mean age was 63 ± 11 years, and 64% had localized disease. One, 3-, and 5-year survival was 37%, 14%, and 11%, respectively. Survival variation among articles was substantial ( P = 0.004), with survival improving across time ( P < 0.0004). Chemotherapy was associated with better survival (hazard ratio [ HR] = 0.53, 68% confidence interval [ CI] = 0.44-0.65; P = 0.002) than surgery alone, radiotherapy alone, nonstandard therapy, or no therapy. Adding local therapy, either surgery ( HR = 0.41, 68% CI = 0.34-0.51; P < 0.0001) or radiotherapy ( HR = 0.33, 68% CI = 0.27-0.41; P < 0.0001), to chemotherapy further improved survival. Adding both did not provide further benefit. The strategy of borrowing from consensus treatment of lung small-cell cancer and analyzing the scarce available esophageal small-cell cancer literature may be beneficial in the study of rare diseases. It confirmed that chemotherapy should be the mainstay of therapy, with additional benefit from adjuvant therapy with either surgery or radiotherapy; both are not needed. [ABSTRACT FROM AUTHOR]

Coptotermes Wasmann is one of the most important genera of wood-destroying insect pests, both in its native and introduced countries. Pyrethroids are among the most widely used insecticides in wood preservation around the world. Consequently, they have often been evaluated against different species of Coptotermes. However, because various test methods have been used between countries, comparing results is problematic. These field trials, using a single aboveground method of exposure, assessed a range of retentions of two pyrethroids (bifenthrin and permethrin) in Pinus radiata D. Don sapwood against two species of Coptotermes in three countries to provide directly comparable results. Coptotermes acinaciformis (Froggatt) in Australia consumed the most nontreated wood, followed by Coptotermes formosanus Shiraki in China, then C. formosanus in the United States, although these data were not significantly different. Both termite species demonstrated a dose-response to wood treated with the two pyrethroids; less wood was consumed as retention increased. Overall, C. acinaciformis consumed relatively little of the treated wood. In comparison, C. formosanus consumed 20-90% of the wood treated at the lowest retentions of the pyrethroids evaluated. Results indicated that C. acinaciformis was more sensitive to pyrethroid toxicity/repellency compared with C. formosanus. Factors that may have influenced the results are discussed. However, using a single aboveground method of exposure across three countries, that suited both species of Coptotermes, made it possible to determine unambiguously the actual differences between the species in their tolerances to the two pyrethroid insecticides. [ABSTRACT FROM AUTHOR]

Aims: The purpose of this study was to provide micrographic evidences for the damaged membrane structure and intracellular structure change of Escherichia coli strain 8099, induced by polyhexamethylene guanidine hydrochloride (PHMG). Methods and Results: The bactericidal effect of PHMG on E. coli was investigated based on β-galactosidase activity assay, fluorescein-5-isothiocyanate confocal laser scanning microscopy, field emission scanning electron microscopy and transmission electron microscopy. The results revealed that a low dose (13 μg ml−1) of PHMG slightly damaged the outer membrane structure of the treated bacteria and increased the permeability of the cytoplasmic membrane, while no significant damage was observed to the morphological structure of the cells. A high dose (23 μg ml−1) of PHMG collapsed the outer membrane structure, led to the formation of a local membrane pore across the membrane and badly damaged the internal structure of the cells. Subsequently, intracellular components were leaked followed by cell inactivation. Conclusions: Dose-dependent membrane disruption was the main bactericidal mechanism of PHMG. The formation of the local membrane pores was probable after exposure to a high dose (23 μg ml−1) of PHMG. Micrographic evidences were provided about the damaged membrane structure and intracellular structure change of E. coli. Significance and Impact of the Study: The presented information helps understand the bactericidal mechanism of PHMG by membrane damage. [ABSTRACT FROM AUTHOR]

BACKGROUND: HGS004 is a fully human immunoglobulin (Ig) G4 monoclonal antibody against CC chemokine receptor 5 (CCR5) with robust in vitro activity against a diverse panel of CCR5-tropic human immunodeficiency virus type 1 (HIV-1) isolates. METHODS: A single-blind, randomized, placebo-controlled study was conducted in patients infected with CCR5-tropic HIV-1 to evaluate the safety, pharmacokinetics, and antiviral activity of HGS004. Sixty-three subjects were randomized into 5 dose cohorts (0.4, 2, 8, 20, and 40 mg/kg) and received a single intravenous dose of HGS004 or placebo. RESULTS: HGS004 was well tolerated, and no dose-limiting toxicities were observed. Pharmacokinetics were nonlinear across the 0.4-40-mg/kg dose range, with dose-proportional increases in maximum concentration, although the area under the curve increased more than proportionally to dose. High levels of receptor occupancy were observed for up to 28 days in the higher-dose cohorts. Plasma HIV-1 RNA reductions of >1 log(10) at day 14 were observed in 14 (54%) of 26 subjects in the 8-, 20-, and 40-mg/kg cohorts. In the 40-mg/kg cohort, 4 of 10 subjects had a >1 log(10) HIV-1 RNA reduction at day 28. Drug concentrations relative to isolate sensitivity (the ratio of the concentration at day 14 to IC(90)) predicted antiviral response on day 14. CONCLUSIONS: HGS004 is safe and well tolerated and demonstrates meaningful antiviral activity when administered to patients infected with CCR5-tropic HIV-1. Copyright © 2008 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012. [ABSTRACT FROM PUBLISHER]