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Wastewater treatment facilities can filter out some plastics before they reach the open environment, yet microplastics often persist throughout these systems. As they age, microplastics in wastewater may both leach and sorb pollutants and fragment to provide an increased surface area for bacterial attachment and conjugation, possibly impacting antimicrobial resistance (AMR) traits. Despite this, little is known about the effects of persistent plastic pollution on microbial functioning. To address this knowledge gap, we deployed five different artificially weathered plastic types and a glass control into the final maturation pond of a municipal wastewater treatment plant in Ōtautahi-Christchurch, Aotearoa/New Zealand. We sampled the plastic-associated biofilms (plastisphere) at 2, 6, 26, and 52 weeks, along with the ambient pond water, at three different depths (20, 40, and 60 cm from the pond water surface). We investigated the changes in plastisphere microbial diversity and functional potential through metagenomic sequencing. Bacterial 16S ribosomal RNA genes composition did not vary among plastic types and glass controls ( P = 0.997) but varied among sampling times [permutational multivariate analysis of variance (PERMANOVA), P = 0.001] and depths (PERMANOVA, P = 0.011). Overall, there was no polymer-substrate specificity evident in the total composition of genes (PERMANOVA, P = 0.67), but sampling time (PERMANOVA, P = 0.002) and depth were significant factors (PERMANOVA, P = 0.001). The plastisphere housed diverse AMR gene families, potentially influenced by biofilm-meditated conjugation. The plastisphere also harbored an increased abundance of genes associated with the biodegradation of nylon, or nylon-associated substances, including nylon oligomer-degrading enzymes and hydrolases.IMPORTANCEPlastic pollution is pervasive and ubiquitous. Occurrences of plastics causing entanglement or ingestion, the leaching of toxic additives and persistent organic pollutants from environmental plastics, and their consequences for marine macrofauna are widely reported. However, little is known about the effects of persistent plastic pollution on microbial functioning. Shotgun metagenomics sequencing provides us with the necessary tools to examine broad-scale community functioning to further investigate how plastics influence microbial communities. This study provides insight into the functional consequence of continued exposure to waste plastic by comparing the prokaryotic functional potential of biofilms on five types of plastic [linear low-density polyethylene (LLDPE), nylon-6, polyethylene terephthalate, polylactic acid, and oxygen-degradable LLDPE], glass, and ambient pond water over 12 months and at different depths (20, 40, and 60 cm) within a tertiary maturation pond of a municipal wastewater treatment plant.

The fragmentation of plastic debris is a key pathway to the formation of microplastic pollution. These disintegration processes depend on the materials' physical and chemical characteristics, but insight into these interrelationships is still limited, especially under natural conditions. Five plastics of known polymer/additive compositions and processing histories were deployed in aquatic environments and recovered after six and twelve months. The polymer types used were linear low density polyethylene (LLDPE), oxo-degradable LLDPE (oxoLLDPE), poly(ethylene terephthalate) (PET), polyamide-6 (PA6), and poly(lactic acid) (PLA). Four geographically distinct locations across Aotearoa/New Zealand were chosen: three marine sites and a wastewater treatment plant (WWTP). Accelerated UV-weathering under controlled laboratory conditions was also carried out to evaluate artificial ageing as a model for plastic degradation in the natural environment. The samples' physical characteristics and surface microstructures were studied for each deployment location and exposure time. The strongest effects were found for oxoLLDPE upon artificial ageing, with increased crystallinity, intense surface cracking, and substantial deterioration of its mechanical properties. However, no changes to the same extent were found after recovery of the deployed material. In the deployment environments, the chemical nature of the plastics was the most relevant factor determining their behaviours. Few significant differences between the four aquatic locations were identified, except for PA6, where indications for biological surface degradation were found only in seawater, not the WWTP. In some cases, artificial ageing reasonably mimicked the changes which some plastic properties underwent in aquatic environments, but generally, it was no reliable model for natural degradation processes. The findings from this study have implications for the understanding of the initial phases of plastic degradation in aquatic environments, eventually leading to microplastics formation. They can also guide the interpretation of accelerated laboratory ageing for the fate of aquatic plastic pollution, and for the testing of aged plastic samples., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Robert Abbel reports financial support was provided by Ministry of Business Innovation and Employment (contract number CO3X1802, Aotearoa Impact and Mitigation of Microplastics (AIM2)). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

An environmentally benign conductive composite that rapidly degrades in the presence of warm water via enzyme-mediated hydrolysis is described. This represents the first time that hydrolytic enzymes have been immobilized onto eco-friendly conductive carbon sources with the express purpose of degrading the encapsulating biodegradable plastic. Amano Lipase (AL)-functionalized carbon nanofibers (CNF) were compounded with polycaprolactone (PCL) to produce the composite film CNF AL -PCL (thickness ∼ 600 μm; CNF AL = 20.0 wt %). To serve as controls, films of the same thickness were also produced, including CNF-AL 5 -PCL (CNF mixed with AL and PCL; CNF = 19.2 wt % and AL = 5.00 wt %), CNF-PCL (CNF = 19.2 wt %), AL x -PCL (AL = x = 1.00 or 5.00 wt %), and PCL. The electrical performance of the CNF-containing composites was measured, and conductivities of 14.0 ± 2, 22.0 ± 5, and 31.0 ± 6 S/m were observed for CNF AL -PCL, CNF-AL 5 -PCL, and CNF-PCL, respectively. CNF AL -PCL and control films were degraded in phosphate buffer (2.00 mg/mL film/buffer) at 50 °C, and their average percent weight loss (Wt avg% ) was recorded over time. After 3 h CNF AL -PCL degraded to a Wt avg% of 90.0% and had completely degraded after 8 h. This was considerably faster than CNF-AL 5 -PCL, which achieved a total Wt avg% of 34.0% after 16 days, and CNF-PCL, which was with a Wt avg% of 7.00% after 16 days. Scanning electron microscopy experiments (SEM) found that CNF AL -PCL has more open pores on its surface and that it fractures faster during degradation experiments which exposes the interior enzyme to water. An electrode made from CNF AL -PCL was fabricated and attached to an AL 5 -PCL support to form a fast-degrading thermal sensor. The resistance was measured over five cycles where the temperature was varied between 15.0-50.0 °C. The sensor was then degraded fully in buffer at 50 °C over a 48 h period.

Plastic pollution causes detrimental environmental impacts, which are increasingly attributed to chemical additives. However, the behaviour of plastic additives in the marine environment is poorly understood. We used a marine deployment experiment to examine the impact of weathering on the extractables profile, analysed by liquid chromatography-mass spectrometry, of four plastics at two locations over nine months in Aotearoa/New Zealand. The concentration of additives in polyethylene and oxo-degradable polyethylene were strongly influenced by artificial weathering, with deployment location and time less influential. By comparison, polyamide 6 and polyethylene terephthalate were comparatively inert with minimal change in response to artificial weathering or deployment time. Non-target analysis revealed extensive differentiation between non-aged and aged polyethylene after deployment, concordant with the targeted analysis. These observations highlight the need to consider the impact of leaching and weathering on plastic composition when quantifying the potential impact and risk of plastic pollution within receiving environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Complex microbial communities colonize plastic substrates over time, strongly influencing their fate and potential impacts on marine ecosystems. Among the first colonizers, diatoms play an important role in the development of this 'plastiphere'. We investigated 936 biofouling samples and the factors influencing diatom communities associated with plastic colonization. These factors included geographic location (up to 800 km apart), duration of substrate submersion (1 to 52 weeks), plastics (5 polymer types) and impact of artificial ageing with UV light. Diatom communities colonizing plastic debris were primarily determined by their geographic location and submersion time, with the strongest changes occurring within two weeks of submersion. Several taxa were identified as early colonizers (e.g. Cylindrotheca , Navicula and Nitzschia spp.) with known strong adhesion capabilities. To a lesser extent, plastic-type and UV-ageing significantly affected community composition, with 14 taxa showing substrate-specificity. This study highlights the role of plastics types-state for colonization in the ocean.

Behavioral health services have been tasked with rapidly adopting and implementing teletherapy during the SARS-CoV-2/COVID-19 pandemic to assure patient and staff safety. Existing teletherapy guidelines were developed prior to the pandemic and do not capture the nuances of rapidly transitioning in-person individual and group-based treatments to a teletherapy format. In this paper, we describe our approach to quickly adapting to a teletherapy technology platform for an intensive outpatient program (IOP) guided by cognitive and behavioral modular principles for adults with serious mental illness. A review of existing guidelines was conducted and the staged approach for teletherapy implementation (Muir et al., 2020) was selected as the most appropriate model for our organizational context. We describe the most pertinent implementation strategies and report our preliminary findings detailing the feasibility of IOPs delivered via telehealth. This model of rapid teletherapy implementation offers practical clinical guidelines for administrators and clinicians seeking to transition traditional in-person behavioral health services to a teletherapy format., (© 2021 Association for Behavioral and Cognitive Therapies. Published by Elsevier Ltd. All rights reserved.)

Additive manufacturing or 3D printing has the potential to displace some of the current manufacturing techniques and is particularly attractive if local renewable waste resources can be used. In this study, rice husk, and wood powders were compounded in polylactic acid (PLA) by twin screw extrusion to produce filaments for fused-deposition modeling 3D printing. The biomasses were characterized in terms of physical features (e.g., particle size, density) and chemical compositions (e.g., solid state nuclear magnetic resonance, ash content). The two biomasses were found to have a different impact on the rheological behavior of the compounds and the extrusion process overall stability. When comparing the complex viscosity of neat PLA to the biomass/PLA compounds, the integration of wood powder increased the complex viscosity of the compound, whereas the integration of rice husk powder decreased it. This significant difference in rheological behavior was attributed to the higher specific surface area (and chemical reactivity) of the rice husk particles and the presence of silica in rice husks compared to the wood powder. Color variations were also observed. Despite the biomass filler and rheological behavior differences, the mechanical properties of the 3D printed samples were similar and predominantly affected by the printing direction., (Copyright © 2019 Le Guen, Hill, Smith, Theobald, Gaugler, Barakat and Mayer-Laigle.)

Purpose: In traumatic brain injury (TBI), hyperglycemia and hypothermia are thought to be associated with poor outcomes, but have not been systematically studied in children. Thus, our aim was to evaluate whether serum glucose and temperature at admission, among other clinical variables, were associated with need for post hospital-discharge seizure medication in children diagnosed with TBI., Methods: We performed a retrospective study of 1814 children who were diagnosed with TBI at a tertiary pediatric hospital. Serum glucose levels at admission and temperature at initial presentation, 12, and 24 h were collected. Ongoing seizure activity was defined as discharge prescription of a seizure-modifying medication., Results: We identified 121 patients with need for continued seizure medications, and 80 patients expired. Independent predictors of prolonged seizures included serum glucose levels above 140 mg/dl (p < 0.003) and 199 mg/dl (p < 0.001), hypothermia (<35 °C), subdural hematoma (p < 0.001), midline shift (p < 0.001), and > 1% temperature change in the first 24 h (p < 0.001). Multivariate regression adjusting for GCS revealed that bilateral bleed (p = 0.008), body-temperature instability (p = 0.026), subdural hematoma (p < 0.001), and mechanism of injury (p = 0.007) were predictive of prolonged seizure activity., Conclusions: In summary, we conclude that body temperature may be playing a more significant role than glycemic control in propensity for ongoing seizure activity in children sustaining TBI.

Unlabelled: Fostriecin is a natural product purified from Sterptomyces extracts with antitumor activity sufficient to warrant human clinical trials. Unfortunately, difficulties associated with supply and stable drug formulation stalled further development. At a molecular level, fostriecin is known to act as a catalytic inhibitor of four PPP-family phosphatases, and reports describing the design of molecules in this class suggest derivatives targeting enzymes within the fostriecin-sensitive subfamily can be successful. However, it is not clear if the tumor-selective cytotoxicity of fostriecin results from the inhibition of a specific phosphatase, multiple phosphatases, or a limited subset of fostriecin sensitive phosphatases. How the inhibition of sensitive phosphatases contributes to tumor-selective cytotoxicity is also not clear. Here, high-content time-lapse imaging of live cells revealed novel insight into the cellular actions of fostriecin, showing that fostriecin-induced apoptosis is not simply induced following a sustained mitotic arrest. Rather, apoptosis occurred in an apparent second interphase produced when tetraploid cells undergo mitotic slippage. Comparison of the actions of fostriecin and antisense-oligonucleotides specifically targeting human fostriecin-sensitive phosphatases revealed that the suppression PP4C alone is sufficient to mimic many actions of fostriecin. Importantly, targeted suppression of PP4C induced apoptosis, with death occurring in tetraploid cells following mitotic slippage. This effect was not observed following the suppression of PP1C, PP2AC, or PP5C. These data clarify PP4C as a fostriecin-sensitive phosphatase and demonstrate that the suppression of PP4C triggers mitotic slippage/apoptosis., Implications: Future development of fostriecin class inhibitors should consider PP4C as a potentially important target. Mol Cancer Res; 11(8); 845-55. ©2013 AACR., (©2013 AACR.)

Nanoporosity is a frequently reported phenomenon in bimetallic particle ensembles used as electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells. It is generally considered a favorable characteristic, because it increases the catalytically active surface area. However, the effect of nanoporosity on the intrinsic activity and stability of a nanoparticle electrocatalyst has remained unclear. Here, we present a facile atmosphere-controlled acid leaching technique to control the formation of nanoporosity in Pt-Ni bimetallic nanoparticles. By statistical analysis of particle size, composition, nanoporosity, and atomic-scale core-shell fine structures before and after electrochemical stability test, we uncover that nanoporosity formation in particles larger than ca. 10 nm is intrinsically tied to a drastic dissolution of Ni and, as a result of this, a rapid drop in intrinsic catalytic activity during ORR testing, translating into severe catalyst performance degradation. In contrast, O2-free acid leaching enabled the suppression of nanoporosity resulting in more solid core-shell particle architectures with thin Pt-enriched shells; surprisingly, such particles maintained high intrinsic activity and improved catalytic durability under otherwise identical ORR tests. On the basis of these findings, we suggest that catalytic stability could further improve by controlling the particle size below ca. 10 nm to avoid nanoporosity. Our findings provide an explanation for the degradation of bimetallic particle ensembles and show an easy to implement pathway toward more durable fuel cell cathode catalysts.

Background: Liposomes have been successfully used as delivery vehicles for anticancer drugs. Both sonication and microfluidic technologies have been used to produce liposomes. The combination of the two methods was evaluated in this study., Materials and Methods: The microfluidic devices, mainly comprising micro-dispensers and a sonicator, were used to produce liposomal nanoparticles. Sonication was used to enhance the reduction of liposome size., Results: Sonication significantly reduced the size of the liposomes. The particle size also decreased as the buffer to solvent flow rate ratio increased. The smallest particle sizes were achieved with a volumetric flow rate of lipids at 0.374 ml/min., Conclusion: The microfluidic devices in combination with ultrasound are simple and may be used to produce liposomal nanoparticles with narrow size distribution.

A series of carbon supported PtRu bimetallic catalysts with varying Pt:Ru ratio were prepared and characterised using ex situ and in situ XRD, in situ EXAFS at 0 V vs. RHE, ex situ XPS and monolayer CO stripping voltammetry. Although the catalysts were found to be well mixed/alloyed, with no evidence of unalloyed Ru (oxides) present, the surfaces of the electrocatalyst nanoparticles were found to be enriched with Pt compared to the nominal bulk composition. The methanol oxidation activities of the catalysts were determined in 1.0 mol dm(-3) H2SO4. In agreement with published studies of polycrystalline bulk PtRu alloys the catalyst with a 0.6 surface fraction of Pt was found to give the best methanol oxidation activity at 30 degrees C. However, at 80 degrees C a greater surface fraction of Ru could be tolerated, with some activity at low current densities found for a Pt surface fraction as low as 0.2. The results support the conclusion that a limited amount of methanol dehydrogenation occurs at Ru sites or Ru dominated surface ensembles at 80 degrees C.

The synthesis of a series of platinum complexes of trans coordination geometry [centered around the general formula, trans-ammine(amine)dichlorodihydroxoplatinum(IV) plus corresponding tetrachloroplatinum(IV) or Pt(II) counterparts] is described as part of a drug discovery program to identify more effective platinum-based anticancer drugs, particularly targeted toward the circumvention of resistance to cisplatin. Complexes have been evaluated for antitumor activity using in vitro and in vivo tumor models. In vitro against a panel of cisplatin-sensitive and -resistant human tumor cell lines (predominantly ovarian), many of the trans platinum complexes studied (e.g., 1, R = cyclohexyl) exhibited comparable potency to cisplatin and also overcame acquired cisplatin resistance, where resistance was due mainly to either reduced drug uptake or enhanced platinum-DNA adduct removal. Moreover, 14 trans complexes showed significant in vivo antitumor activity against the subcutaneous murine ADJ/PC6 plasmacytoma model; all were platinum(IV) complexes, 13/14 possessing axial hydroxo ligands the other possessing axial ethylcarbamato ligands. Where tested, all of their respective platinum(II) or tetrachloroplatinum(IV) counterparts were inactive. Notably, three dihydroxoPt(IV) complexes (18, 29, 34) (R = c-hexyl, c-heptyl, and 1-adamantyl) retained some efficacy against a cisplatin-resistant variant of the ADJ/PC6. Compounds 18 (trans-[PtCl2(OH)2NH3-(RNH2)]) R = c-C6H11, 22, R = Me3C, 27, R = n-C6H13, 28, R = PhCH2, and 36 (trans-[PtBr2(OH)2NH3(c-C6H11NH2)]) also produced evidence of antitumor activity (> 5 days growth delay) against subcutaneously grown advanced stage human ovarian carcinoma xenografts. These data demonstrate that a series of trans-ammine(amine)dichlorodihydroxoplatinum(IV) complexes are active in vivo against both murine and human subcutaneous tumor models and represent potential leads to a new generation of platinum-based anticancer drug.