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• Changes in survey mode introduce artifacts in youth ENDS use prevalence trends. • PATH changed from self- to telephone-interview during COVID, in Wave 5.5 (2020). • Reported ENDS use was lower in telephone (vs. self-) interviews (4.6 % vs. 8.6 %). • Youth ENDS use declined from 2019–20, but artifact magnified the apparent decline. • Artifact also produced a false uptick in 2021, when true ENDS use trends plateaued. The Population Assessment of Tobacco and Health (PATH) provides annual prevalence data on youth use of electronic nicotine delivery systems (ENDS). However, trends may be complicated by COVID-related changes in survey mode (self-completed vs. telephone interview) across 2019–2021. Trends in past 30-day (P30D) ENDS use over PATH waves 5 (2019; 100 % self-completed), 5.5 (2020; 100 % telephone interview), and 6 (2021; 33.5 % self-completed, 66.5 % telephone interview) were examined among continuing youth, overall and within survey mode. Further analyses examined the nature of these changes by examining 1) potential response biases in social contexts of nicotine use, and 2) sources of ENDS over time. Telephone interviewees were less likely to report ENDS use (4.6 % vs. 8.6 % for self-completers), and more likely to report social disapproval of nicotine use, suggesting a reporting bias in telephone interviews. Survey-mode-naïve analyses suggested a large decline in P30D ENDS use prevalence between 2019–20 (10.2–4.6 %) followed by an apparent uptick in 2021 (5.9 %); however, comparing like-to-like survey modes showed a more modest decline (10.2 % in 2019; 8.6 % in 2021; self-completed) with no change between 2020 and 2021 (4.6 % in both; telephone interviews). Analyses suggested that the mode effects were partly, but not wholly, related to social desirability effects. Changes in PATH survey mode introduced artifacts into ENDS use prevalence, possibly due in part to social desirability bias suppressing reporting in telephone interviews, rather than a true uptick. It is essential to account for survey mode in PATH surveys. [ABSTRACT FROM AUTHOR]

Subsurface engineering systems undergo large changes in pore pressure, which can have drastic effects on their ability to transport and store fluids. For rock samples retrieved from conventional reservoirs, standard core analysis procedures provide suitable estimates of petrophysical properties, such as porosity and permeability. However, performing similar investigations on low-permeability systems like shales and tight gas sands remains a challenge. Steady-state gas permeametry is considered the gold standard for analyzing low-permeability cores, but researchers often forego it in favor of faster but less reliable methods. Attempting a conventional permeability test on a tight plug sample typically results in miniscule flow rates that only expensive, specialized equipment can measure directly. Furthermore, these time-consuming tests are best run multiple times under varying ranges of pore pressure and confining stress. Doing so allows one to anticipate suitably the changes in permeability that will occur because of the expected changes in reservoir conditions. This study describes the methodology of the Randolph Steady-State Core Analysis Laboratory (RaSSCAL), a new experimental design and data analysis algorithm that accounts for changes in permeability over the range of pore pressures and confining stresses that occur during processes like unconventional hydrocarbon recovery and geologic carbon sequestration. Routine steady-state core analysis requires relatively small pressure drops across the sample so a uniform apparent permeability can be assumed. The approach outlined here enables an effective interpretation of core-flood data in the presence of arbitrarily large pressure gradients. The experiment maintains a near-constant pressure difference of arbitrary magnitude across a core-plug sample and indirectly measures the flow rate induced by that gradient using a differential pressure transmitter. Tests were performed on a Marcellus Shale sample from Bedford, Pennsylvania and an Oriskany Sandstone sample from Berkeley Springs, West Virginia over a wide array of pore pressures and net confining stresses using helium and methane gas. Having a quantifiable understanding of how the permeability of the system may change during the various stages of subsurface activity should significantly enhance the ability to optimize design outcomes. This will ultimately lead to improved oil and gas recovery and better predictions of injectivity and storage capacity during carbon-storage operations. • Shale formations undergo large pressure gradients during production. • A new experimental method applies representatively large pressure gradients to lab samples. • The flow model accounts for slip flow and net effective stress changes. • Model predictions show good agreement with measured induced flow rates. [ABSTRACT FROM AUTHOR]

Objective Evaluate the relationship between patient preferences for total knee replacement (TKR) with receipt of TKR, and assess participant characteristics that may influence change in willingness to undergo TKR. Methods Structured interviews of knee osteoarthritis (OA) patients were conducted. Logistic regression models were conducted to assess the association between baseline willingness and eventual receipt of TKR, adjusted for sociodemographic and clinical variables. Mixed models for repeated measures were used to estimate the effects of sex, race, social support, Δ WOMAC, and orthopedic consult on change in willingness. Results A total of 589 participants were willing, and 215 participants were unwilling to undergo TKR. Willing participants, compared to others, were more often White (69.4% vs. 48.4%), with more than a high school education (60.8% vs. 47.0%) and employed (39.1% vs. 26.5%). At follow-up, the odds of having TKR were twice as high among those who were willing to have the procedure at baseline, but this was no longer significant when adjusted for demographic variables (adjusted OR = 1.82, 95% CI: 0.89–3.69). Willingness to undergo TKR declined over 2 years. Among those who were willing to undergo TKR at baseline but did not obtain one, only 66.5% were still willing at the 2-year follow-up. This decline was less among those who had a greater increase (>median) in WOMAC disability (adjusted Δ = −0.34, 95% CI: −0.47 to −0.20) than those who had minimal change in their WOMAC disability ( p = 0.08). The decline in willingness was also less among those who had seen an orthopedic surgeon (adjusted Δ = −0.32, 95% CI: −0.46 to −0.17) than those who did not ( p = 0.05). Conclusions Preference for TKR was consistent with TKR surgery utilization, but not after controlling for patient demographic characteristics. Willingness to undergo TKR declined over time, but this decrease was mitigated by worsening OA-related disability and by consultation with an orthopedic surgeon. [ABSTRACT FROM AUTHOR]

Objective To determine whether changes in preoperative osteoarthritis (OA) symptoms are associated with improvement after total knee replacement (TKR) and to identify predictors of clinically significant improvement. Methods Data on Osteoarthritis Initiative participants who were annually assessed and underwent TKR were included. T0 was the assessment prior to TKR while T−1 was the assessment prior to that. T+2 was the second assessment after TKR. We compiled data on the Western Ontario and McMaster Universities OA Index (WOMAC), OA-related symptoms, and radiographic severity. We defined clinically significant improvement as improvement in WOMAC total score ≥ to the minimal important difference (MID) (0.5 SD of mean change) between T0 and T+2 and also considered other definitions of improvement. Logistic regression models were performed to evaluate the relationship between improvement and preoperative measures. Results Improved ( n = 211) compared to unimproved ( n = 58) patients had greater worsening of their WOMAC pain ( p = 0.002) and disability ( p < 0.001) from T−1 to T0. Preoperative measures as predictors of improvement included higher WOMAC disability (OR = 1.08, p < 0.001), presence of chronic OA symptoms in the surgical knee (OR = 5.77, p = 0.033), absence of OA-related symptoms in the contralateral knee (OR = 9.25, p < 0.001), exposure to frequent knee bending (OR = 3.46, p = 0.040), and having a Kellgren–Lawrence x-ray grade of ≥2 in the contralateral knee (OR = 4.71, p = 0.010). Conclusions More than 75% of participants had improvement after TKR. Improved patients were more likely to have escalation of OA pain and disability prior to surgery than unimproved patients. Other preoperative measures predicted improvement after TKR. [ABSTRACT FROM AUTHOR]

Abstract: Photosynthetic marine algae are attractive targets for the production of biofuels and bio-products because they have the ability to capture and fix carbon dioxide using solar energy and they grow in seawater, thereby minimizing fresh water usage. Algae are a large and diverse group and transformation of algal chloroplasts has been limited to very few examples, mainly the model freshwater alga, Chlamydomonas reinhardtii. However, the potential for metabolic engineering and recombinant protein production using algal chloroplasts has been well demonstrated in this model species. Here we report the transformation of the chloroplast of the marine green alga Dunaliella tertiolecta. D. tertiolecta is an ideal species for biofuel production because it can maintain relatively high growth rates in a wide range of pH and salt concentrations, and because it contains relatively high lipid content. Here we show that transformation of the chloroplast of D. tertiolecta can occur by homologous recombination and selection for resistance to the antibiotic erythromycin using the erythromycin esterase gene, ereB. We successfully produce measurable quantities of five different classes of recombinant enzymes; xylanase, α-galactosidase, phytase, phosphate anhydrolase, and β-mannanase, in the plastids of D. tertiolecta or C. reinhardtii. This was achieved by transforming the plastid of D. tertiolecta via particle bombardment using a D. tertiolecta psbD promoter with 5′ UTR and psbA terminator with 3′ UTR to drive stable expression of codon optimized transgenes. Similar strategies should allow for recombinant protein production in many species of marine algae. [Copyright &y& Elsevier]

Abstract: In this work we present the results of a molecular simulation study of two different tetracationic bis iron(II) supramolecular cylinders interacting with DNA. One cylinder has been shown to bind in the major groove of DNA and to induce dramatic coiling of the DNA; the second is a derivative of the first, with additional methyl groups attached so as to give a larger cylinder-radius. The simulations show that both cylinders bind strongly to the major groove of the DNA, and induce complex structural changes in A–T rich regions. Whereas the parent cylinder tends to bind along the major groove, the derivatised cylinder tends to twist so that only one end remains within the major groove. Both G–C rich and A–T rich binding sites for the derivatised cylinder are discussed. [Copyright &y& Elsevier]

• Youth use of e-cigarettes peaked in 2019 and declined by nearly half in 2020. • Youth cigarette smoking declined to all-time lows in 2020. • Youth e-cigarette users migrated from pods to disposable devices between 2019 and 2020. • Use of fruit/sweet-flavored e-cigarettes remained stable between 2019 and 2020. • However, the use of these flavors became concentrated in disposables in 2020. Youth use of electronic nicotine delivery systems (ENDS) is a continuing concern, making it important to assess evolving patterns, especially as non-tobacco, non-menthol (NTM) flavors were withdrawn for pod-based (but not disposable) ENDS in February 2020. Trends in past-30-day (P30D) ENDS use and smoking prevalence, usual device type, flavor (tobacco, mint/menthol, or fruit/sweet/other), and regular/last-used brand in PATH Waves 4 (2017), 4.5 (2018), 5 (2019), and 5.5 (2020) were examined. Shifts between 2019 and 2020 in flavor use for pods and disposables were examined. P30D ENDS use peaked in 2019 at 8.6 % of all youth, subsequently declining by nearly half to 4.5 % in 2020. Meanwhile, P30D cigarette smoking declined to an all-time low (1.3 %) in 2020. Within this overall decline, consumption shifted to disposable ENDS, which increased nearly 10-fold (from 5.0 % to 49.2 % of P30D ENDS users). Relatedly, use of fruit/sweet/other flavors remained similar overall between 2019 and 2020 (approximately 75–80 % of P30D ENDS users), but the use of these flavors became concentrated in disposable ENDS in 2020 (a 12-fold increase from 4.4 % to 58.4 % of fruit/sweet/other-flavor users). PATH results show similar trends to other US national surveys in youth ENDS trends. The removal of non-tobacco, non-menthol flavors in pod-based ENDS (while remaining available in disposables) has likely driven youth towards disposable devices, resulting in continued high use of fruit/sweet/other flavors, which are now predominant in users of disposable ENDS. Wave 5.5 is uninformative regarding brand use because common disposable brands were not queried. [ABSTRACT FROM AUTHOR]

Abstract: The prevalence of antibiotic resistance has resulted in the need for new approaches to be developed to combat previously easily treatable infections. Here we investigated the potential of the synthetic metallomolecules [Fe2L3]4+ and [Cu2(L’)2]2+ as antibacterial agents. Both molecules have been shown to bind DNA; [Fe2L3]4+ binds in the major groove and causes DNA coiling, whilst [Cu2(L’)2]2+ can act as an artificial nuclease. The work described here shows that only [Fe2L3]4+ is bactericidal for Bacillus subtilis and Escherichia coli. We demonstrate that [Fe2L3]4+ binds bacterial DNA in vivo and, strikingly, that it kills B. subtilis cells very rapidly. [Copyright &y& Elsevier]

The interaction of enantiomerically pure dinuclear complexes of the form [Ru2(L–L)4L1]4+ (where L–L=2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen) and L1 =bis(pyridylimine) ligand ((C5H4N)C ═ N(C6H4))2CH2)) with ct-DNA have been investigated by absorbance, circular dichroism, fluorescence displacement assays, thermal analysis, linear dichroism and gel electrophoresis. The complexes all bind more strongly to DNA than ethidium bromide, stabilise DNA and have a significant bending effect on DNA. The data for Δ,Δ-[Ru2(bpy)4L1]4+ are consistent with it binding to DNA outside the grooves wrapping the DNA about it. By way of contrast the other complexes are groove-binders. The phen complexes provide a chemically and enantiomerically stable alternative to the DNA-coiling di-iron triple-helical cylinder previously studied. In contrast to the di-iron helicates, the phen complexes show DNA sequence effects with Δ,Δ-[Ru2(phen)4L1]4+ binding preferentially to GC and Λ,Λ-[Ru2(phen)4L1]4+ to AT. [Copyright &y& Elsevier]

Abstract: Purpose: The aim of the study was to compare semiquantitative assessment of focal cartilage damage using the dual echo at steady state (DESS)- and intermediate-weighted (IW) fat suppressed (fs) sequences at 3T MRI. Methods: Included were 201 subjects aged 35–65 with frequent knee pain. MRI was performed with the same sequence protocol as in the Osteoarthritis Initiative (OAI): sagittal IW fs, triplanar DESS and coronal IW sequences. Cartilage status was scored according to the WORMS system using all five sequences. A total of 243 focal defects were detected. In an additional consensus reading, the lesions were evaluated side-by-side using only the sagittal DESS and IW fs sequences. Lesion conspicuity was graded from 0 to 3, intrachondral signal changes adjacent to the defect were recorded and the sequence that depicted the lesion with larger diameter was noted. Wilcoxon signed-rank tests, controlled for clustering by person, were used to examine differences between the sequences. Results: 37 (17.5%) of the scorable lesions were located in the medial tibio-femoral (TF), 48 (22.7%) in the lateral TF and 126 (59.7%) in the patello-femoral compartment. 82.5% were superficial and 17.5% full-thickness defects. Conspicuity was superior for the IW sequence (p <0.001). The DESS sequence showed more associated intrachondral signal changes (p <0.001). In 103 (48.8%) cases, the IW fs sequence depicted the lesions as being larger (p <0.001). Conclusions: The IW fs sequence detected more and larger focal cartilage defects than the DESS. More intrachondral signal changes were observed with the DESS. [Copyright &y& Elsevier]

Abstract: The novel steroidal carrier ligand 17-α-[4′-ethynyl-dimethylbenzylamine]-17-β-testosterone (ET-dmba 1) and the steroid — C,N-chelate platinum(II) derivatives [Pt(ET-dmba)Cl(L)] (L = DMSO (2) and PTA (3; PTA =1,3,5-triaza-7-phosphaadamantane)) have been prepared. Values of IC50 were calculated for the new platinum complexes 2 and 3 against a panel of human tumor cell lines representative of ovarian (A2780 and A2780cisR) and breast cancers (T47D). At 48h incubation time complexes 2 and 3 show very low resistance factors (RF of <2) against an A2780 cell line which has acquired resistant to cisplatin and were more active than cisplatin (about 4-fold for 3) in T47D (AR+, AR=androgen receptor). Compound 1 retains a moderate degree of relative binding affinity (RBA=0.94%) for androgen receptors. The cytotoxicity of the non steroidal platinum analogues [Pt(dmba)Cl(L)] (dmba=dimethylbenzylamine; L=DMSO (4) and PTA (5)) has also been studied for comparison purposes. Theoretical calculations at the BP86/def2-TZVP level of theory on complex 3 have been undertaken. [Copyright &y& Elsevier]

Abstract: In order to probe the DNA-helicate interactions responsible for the DNA binding and remarkable changes of the DNA secondary structure induced by a tetracationic bi-metallo helicate [Fe2(L1)3]4+ (L1 =C25H20N4), we have designed and synthesised derivatives with hydrophobic methyl groups at different positions on the ligand backbone. Two dimetallo helicates [Fe2(Li)3]4+ were prepared using ligands L3 and L5 with the methyl substituent on, respectively, the 3 and 5 positions of the pyridyl ring thus producing a wider or slightly longer tetracationic DNA binder. UV/visible absorbance, circular and linear dichroism spectroscopies have been used to characterize the interactions of the cylinders with DNA with the aim of investigating any sequence preference or selectivity upon binding. Competitive binding studies using fluorescent dyes Hoechst 33258 (a minor groove binder), ethidium bromide (an intercalator) and a major groove binding cation (cobalt (III) hexammine) which induces the B→Z transition have been employed to determine the binding geometries of the enantiomers of two methylated helicates (L3 and L5) to DNA and compare with the data obtained previously for the unmethylated analogue (L1). The results demonstrate that the racemic mixtures and the resolved enantiomers of all helicates bind to DNA inducing structural changes. The overall conclusion from the effect of adding these groups to the surface of the parent helicate is that increasing the width (L3) reduces the DNA binding strength, the bending and coiling effect and the groove selectivity of the enantiomers compared with the parent compound. There is limited evidence to suggest a slight GC sequence preference. Lengthening the helicate (L5) results in DNA interactions similar to those of the parent compounds, with an increased preference of the P enantiomer for the minor groove indicating an enhancement of mode selectivity. [Copyright &y& Elsevier]

The non-covalent interaction of five novel ruthenium(II) bis-terpyridine complexes with calf thymus DNA and, where appropriate, with poly[d(G–C)]2 and poly[d(A–T)]2 is described. Each complex is functionalised with aryl tail groups in the 4′ position of the terpyridine ligands ((i) 9-anthracenyl, (ii) 4,4′-biphenyl, (iii) β-naphthyl, (iv) 9-phenanthrenyl, and (v) 1-pyrenyl). Circular dichroism and linear dichroism show that the binding of three of the complexes (phenanthrenyl, anthracenyl and pyrenyl) at low metal complex concentration is dominated by intercalation of the aryl tail groups between the DNA bases. The complex with the biphenyl tail predominantly exhibits groove binding with no significant tail intercalation. The naphthyl derivative binds both by intercalation and a non-intercalative mode even at low metal complex concentrations. At high metal complex concentrations, aggregation of the complexes on the DNA is observed. Resonance light scattering indicates that the aggregates are of low nuclearity along the groove. [Copyright &y& Elsevier]