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This study presents a new method combining cold plasma-activated oxygen (CPAO) and microwave (MW) to decontaminate milkshake powder, exploring its effectiveness, mechanisms, and quality impact. CPAO (6 min) alone reduced bacterial load by 0.419 log CFU/g, and MW (3 min) by 0.030 log CFU/g. However, their co-application significantly amplified decontamination, achieving a 1.265 log CFU/g reduction. CPAO-MW co-treatment inflicted more oxidative damage on bacterial cell membranes and intracellular antioxidant defense system, leading to higher mortality. It also raised protein and lipid oxidation, while decreasing vitamin C and A levels in the powder. Specifically, CPAO (6 min)-MW (3 min) co-treatment increased the carbonyl content from 0.438 to 0.891 nmol/mg protein, malondialdehyde from 0.824 to 0.996 mg/kg, and lowered vitamin C from 162.151 to 137.640 mg/kg, and vitamin A from 2.05 to 1.38 mg/kg. This study shows CPAO-MW is effective for decontaminating powdered foods but highlights a need to reduce negative effects. [Display omitted] • Microwave boosted CPAO's ability to decontaminate microbes in milkshake powder. • CPAO-MW caused oxidative damage to the cell membrane and antioxidant defense system. • CPAO-MW led to a certain oxidation of the main nutrients in milkshake powder. [ABSTRACT FROM AUTHOR]

The removals of arsenic and selenium pollutants are always urgent desires for the water security. In this study, both sorption and catalysis strategies were combined for the effective removals of As(V) and Se(VI) over magnetic graphene oxide sheets (GOs)-oxidized carbon nanotubes (OCNTs) hydrogels. The sorption behavior facilitated the operation of catalysis reactions, meanwhile, the catalytic reduction promoted the release of occupied sorption sites and then restarted a new sorption-catalysis cycle. The synergic effect of sorption and catalysis realized 258.2 mg g−1 for As(V) enrichment capacity on MPG2T1, and ultra-fast sorption and catalysis equilibriums were identified within 9 min. In the case of Se(VI), a moderate enrichment performance was observed to be 46.2 mg g−1. Similarly, the ultra-fast sorption and reduction of Se(VI) were realized within 2 min. In the competition experiments, only SO 4 2−, SO 3 2−, and HPO 4 2− showed interference for As(V) and Se(VI) removals. These results testified the superiority of the synergy effect of sorption and catalysis, and the feasibility of 3D magnetic GOs-OCNTs hydrogel in practical implementations. The effective removals of As(V) and Se(VI) were realized on the 3D GOs-OCNTs hydrogel based on ultra-fast sorption and catalysis behaviors within a few minutes. Image 1 • The synergistic effects of sorption and catalysis demonstrated the effective removals of As(V) and Se(VI). • Ultra-fast sorption was realized within 9 min for As(V) removal, and 2 min for Se(VI), respectively. • Effective catalysis was achieved within 2 min for the reductions of As(V) and Se(VI). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Comparison study on 5 regioisomeric pyrene dyes indicate the regio-effect with an order of 1-pyrenyl > 4-pyrenyl > 2-pyrenyl. • 4-Substituted isomer demonstrated exceptionally large Stokes shift and high fluorescence quantum yield. • Preliminary fluorescent cell imaging indicated these pyrene cationic dyes could be active mitochondrial probes. Abstract Two series of regioisomeric mono-substituted far-red fluorescent pyrene-indolium and pyrene-pyridinium conjugated dyes were synthesized, and their structures were ambiguously determined by single crystal X-ray diffractions. The photophysical properties of these pyrene-containing dyes in several solvents were investigated to figure out the modulation by changing the site of substituent on the pyrene moiety. The 4-substituted pyrene dyes Py-4 and PP-4 exceptionally demonstrated remarkable fluorescence quantum yield and much larger Stokes shift than their regioisomers (Δ ṽ of PP-4 is 7732 cm−1 in acetonitrile). Preliminary cell staining and fluorescent imaging experiments indicated that t -Bu-Py-4 could be used as mitochondrial probe with good selectivity and low cytotoxicity. [ABSTRACT FROM AUTHOR]

Large and complex engineering systems are usually assembled by subcomponents with different energy dissipation levels. Therefore, these systems often contain multiple damping models, which may lead to great difficulties in analyzing efficiently. In this paper, an efficient modal projection-based reduction method, which accounts for transient dynamic responses of structural system with multiple damping models, is proposed in the framework of a modified precise integration method. Two robust modal reduction bases, namely multi-model method (MM) and modal strain energy by first-order correction method (MSEC), are introduced to reduce the order of the original system. Based on the reduced system and a general damping model (GDM), a reduced state-space formalism for the structural system with multiple damping models is developed. Finally, the transient dynamic responses are derived using a modified precise integration method on the reduced stage. The numerical stability, accuracy and complexity are discussed. Two numerical examples are illustrated to assess the performances of the computational accuracy and efficiency. The results indicate that the proposed method is more efficient than other methods and most suitable for large-scale problems with rather good accuracy. [ABSTRACT FROM AUTHOR]

Clarifying the reaction process and specific mechanism between variable-valence elements and oxidized carbon nanoparticles is essential to evaluate the environmental impact of carbon nanomaterials. In this study, the photocatalytic reduction of Cr(VI) on oxidized carbon nanotubes (OCNTs), oxidized graphene ribbons (OGRs), and graphene oxide sheets (GOs) was explored by batch experiments and spectroscopic analyses. The reaction efficiencies strongly depended on the number of oxygenated groups in the oxidized carbon nanoparticles. The abundant oxygenated groups enabled the GOs to exhibit the highest photocatalytic activity, followed by the OGRs and OCNTs. As a result, the photoreduction efficiency of Cr(VI) reached 96% for GOs, whereas those of OGRs and OCNTs were only 40% and 13%, respectively. In addition, different types of oxygenated groups exhibited various activities based on molecular model tests, following the sequence carboxylic > hydroxyl > carbonyl > ether > aldehyde > edge. Based on the underlying relationship between the oxygenated groups, topological structures, and mechanical strain in the carbon nanoparticles, we speculate that mechanical strain plays a critical role in the formation of oxygenated groups, thereby regulating their photocatalytic activities. The findings in this work provide novel insights into the roles of oxygenated groups and the mechanical strain of carbon nanoparticles in their environmental behavior. [Display omitted] • Carbon nanoparticles with abundant oxygenated groups showed the superior photoreduction efficiency of Cr(VI). • The characteristic oxygenated groups represented distinct photoactivities. • The underlying relationship between oxygenated groups and mechanical strains regulated photocatalytic behavior of carbon nanoparticles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A level set-based multi-material topological design method is proposed for multiphase micro-architectured materials. • A difference-set-based level set model is combined with an alternating active-phase algorithm to facilitate the extension to more phases. • Optimized topologies of multiphase micro-architectured materials are featured with smooth boundaries and distinct interfaces. • Both numerical examples and additive-manufactured specimens demonstrate the effectiveness of the proposed method. Micro-architectured materials with periodically configured microstructures are widely used in various engineering fields due to their superior mechanical properties. Compared with conventional topology design with one single material, topological design with multiple materials can provide a better solution as the expanded design freedom. This paper presents a level set-based multi-material topological design method for micro-architectured materials involving three phases or more. In this method, a difference-set-based multi-material level set model is employed to represent the topology of each phase, in which N + 1 phases can be precisely represented by the sequential difference-set of N level set functions without any overlaps and redundant regions. By using an alternating active-phase algorithm, the multi-material topology design problem with N + 1 phases is splitted into N (N + 1)/2 binary-phase topological design sub-problems, where each sub-problem involves fewer design variables and volume constraints. The effective properties of multiphase micro-architectured materials are evaluated by a numerical homogenization approach, and their topological evolutions of two active phases in each sub-problem can be readily achieved by updating a single level set function, which greatly facilitate the extension to topological design problems with more phases. Both numerical examples and additive-manufactured specimens demonstrate the effectiveness of the proposed method for designing multiphase micro-architectured materials. [ABSTRACT FROM AUTHOR]

Engineering structures are often assembled by subsections with various levels of energy dissipation, which lead to great difficulties in analyzing. In this paper, a direct time integration method is proposed to solve the dynamic responses of structural systems involving multiple nonviscous damping models. Based on a general non-viscously damped model, an extended state-space scheme for the damped system is derived. Then, an implicit time integration method using linear approximations is developed built on the extended state-space formalism. The stability and efficiency of the method are discussed by theoretical and numerical analyses. The method is illustrated by two examples. [ABSTRACT FROM AUTHOR]

Purpose: To study the relationship between fluorodeoxyglucose (FDG) uptake in pulmonary tissue after radical radiation therapy (RT) and the presence and severity of radiation pneumonitis. Methods and Materials: In 88 consecutive patients, 18F-FDG–positron emission tomography was performed at a median of 70 days after completion of RT. Patients received 60 Gy in 30 fractions, and all but 15 had concurrent platinum-based chemotherapy. RT-induced pulmonary inflammatory changes occurring within the radiation treatment volume were scored, using a visual (0 to 3) radiotoxicity grading scale, by an observer blinded to the presence or absence of clinical radiation pneumonitis. Radiation pneumonitis was retrospectively graded using the Radiation Therapy Oncology Group (RTOG) scale by an observer blinded to the PET radiotoxicity score. Results: There was a significant association between the worst RTOG pneumonitis grade occurring at any time after RT and the positron emission tomograph (PET) radiotoxicity grade (one-sided p = 0.033). The worst RTOG pneumonitis grade occurring after the PET scan was also associated with the PET radiotoxicity grade (one-sided p = 0.035). For every one-level increase in the PET toxicity scale, the risk of a higher RTOG radiation pneumonitis score increased by approximately 40%. The PET radiotoxicity score showed no significant correlation with the duration of radiation pneumonitis. Conclusions: The intensity of FDG uptake in pulmonary tissue after RT determined using a simple visual scoring system showed significant correlation with the presence and severity of radiation pneumonitis. 18F-FDG–PET may be useful in the prediction, diagnosis and therapeutic monitoring of radiation pneumonitis. [ABSTRACT FROM AUTHOR]

Abstract: Planarians display a concentration-related reduction in locomotor activity when amphetamine, cocaine, cannabinoid, or benzodiazepine exposure is abruptly discontinued. In the present study, we tested the hypothesis that abrupt discontinuation of methamphetamine would also cause withdrawal-like behavior in planarians and that the withdrawal-like behavior would be prevented by nociceptin, which has been shown to modulate the effects of methamphetamine in mammals. We observed a concentration-related reduction of locomotor behavior when planarians exposed to methamphetamine (0.1–100μM) were tested in drug-free water. The withdrawal-like behavior was abolished when methamphetamine (10μM)-exposed planarians were placed into water containing nociceptin (10μM) or when planarians co-exposed to methamphetamine (10μM) and nociceptin (10μM) were placed into drug-free water. The effects of nociceptin were abolished in the presence of a nociceptin receptor antagonist, JTC-801 (1μM). Planarians did not display a change in locomotor behavior during exposure to nociceptin (10μM) or JTC-801 (1μM) by themselves. These results (1) reveal a functional interaction between nociceptin and methamphetamine in planarians and (2) provide evidence that nociceptin blocks methamphetamine-induced withdrawal-like behavior in planarians through a JTC-801-sensitive mechanism. [Copyright &y& Elsevier]

Abstract: Numerous studies support a role for the endogenous 5-hydroxytryptamine (5-HT) system in the hypothermic effect of capsaicin. None of those studies, however, selectively delineate a role for 5-HT reuptake or 5-HT receptors in this regard. In the present investigation, we determined if the blockade of 5-HT reuptake or the activation of 5-HT1A or 5-HT2 receptors modulates capsaicin-evoked hypothermia. The administration of capsaicin (0.2–1mg/kg, i.m.) produced dose-related hypothermia. Fluoxetine (10mg/kg, i.p.), a selective serotonin reuptake inhibitor (SSRI), did not affect body temperature. For combined administration, pretreatment with fluoxetine (10mg/kg, i.p.) significantly attenuated the hypothermia caused by capsaicin (0.5 and 1mg/kg, i.m.). For the 5-HT receptor experiments, we pretreated rats with either WAY 100635, a 5-HT1A receptor antagonist, or mianserin, a 5-HT2 receptor antagonist, and then administered a fixed, hypothermic dose of capsaicin (1mg/kg, i.m.). WAY 100635 (1mg/kg, s.c.) administration did not affect capsaicin-evoked hypothermia. This indicates that 5-HT1A receptor activation does not play a major role in the hypothermic effect of capsaicin. In contrast, pretreatment with mianserin (10mg/kg, i.p.) enhanced the hypothermic effect of capsaicin (1mg/kg, i.m.). The present data reveal that capsaicin-evoked hypothermia in rats is attenuated by the blockade of 5-HT reuptake and enhanced by the antagonism of 5-HT2 receptors. [Copyright &y& Elsevier]

Abstract: The present study used the endpoint of hypothermia to investigate cannabinoid and nociceptin/orphanin FQ (N/OFQ) interactions in conscious animals. Prior work has established that cannabinoids produce hypothermia by activating central cannabinoid CB1 receptors. The administration of N/OFQ into the brain also causes significant hypothermia. Those data suggest a link between cannabinoid CB1 receptors and N/OFQ peptide (NOP) receptors in the production of hypothermia. Therefore, we determined if NOP receptor activation is required for cannabinoid-evoked hypothermia and if cannabinoid CB1 receptor activation is necessary for N/OFQ-induced hypothermia. In actual experiments, a cannabinoid agonist, WIN 55212-2 (2.5, 5, and 10mg/kg, i.p.), caused significant hypothermia in male Sprague-Dawley rats (200–225g). A NOP receptor antagonist, JTC-801 (1mg/kg, i.p.), did not affect body temperature. For combined administration, JTC-801 (1mg/kg, i.p.) blocked a significant proportion of the hypothermia caused by each dose of WIN 55212-2 (2.5, 5, and 10mg/kg, i.p.). JTC-801 (1mg/kg, i.p.) also blocked the hypothermia caused by another cannabinoid agonist, CP-55, 940 (1mg/kg, i.p.). In separate experiments, the direct administration of N/OFQ (9μg/rat, i.c.v.) into the brain produced significant hypothermia. The hypothermic effect of N/OFQ was blocked by JTC-801 (1mg/kg, i.p.) but not by a selective cannabinoid CB1 antagonist, SR 141716A (5mg/kg, i.m.). The finding that a NOP receptor antagonist abolishes a significant percentage of cannabinoid-induced hypothermia suggests that NOP receptor activation is required for cannabinoids to produce hypothermia. This interaction, quantitated in the present study, is the first evidence that NOP receptors mediate a cannabinoid-induced effect in conscious animals. [Copyright &y& Elsevier]

Abstract: The present study investigated the effect of a drug combination of capsaicin and l-NAME on hypothermia in rats. Capsaicin administration (0.1, 0.25, 0.5, 1 and 2mg/kg, i.m.) caused a significant hypothermia. l-NAME (50mg/kg, i.p.), a nonspecific nitric oxide synthase (NOS) inhibitor, was ineffective. For combined administration, progressively increasing doses of capsaicin (0.1, 0.25, 0.5, 1 and 2mg/kg, i.p.) were given with a non-hypothermic dose of l-NAME (50mg/kg, i.p.). Experiments revealed that l-NAME (50mg/kg, i.p.) enhanced the hypothermic response to capsaicin (0.25, 0.5, 1, and 2mg/kg, i.m.). Comparison of the graded dose–effect curves for capsaicin alone and capsaicin plus l-NAME revealed a significant difference (P <0.05), thus indicating synergy for the drug interaction. To determine if l-NAME acted centrally, a fixed dose of l-NAME (1mg/rat, i.c.v.) was given with graded doses of capsaicin (0.25, 0.5, 1, and 2mg/kg, i.m.). l-NAME (1mg/rat, i.c.v.) only enhanced the hypothermia at a single dose of capsaicin (0.5mg/kg, i.m.). The super-additive hypothermia produced by the concurrent administration of capsaicin and l-NAME (50mg/kg, i.p.) is the first evidence of synergy for a drug combination of capsaicin and a NOS inhibitor. The synergy is apparent only when l-NAME is given systemically, thus indicating that the inhibition of peripheral NO production enhances the hypothermic response to capsaicin. [Copyright &y& Elsevier]

Abstract: AM 404 inhibits endocannabinoid uptake and enhances the cannabinoid CB1-mediated effects of endogenous cannabinoids. Accumulating evidence also suggests that AM 404 acts at sites other than the endocannabinoid system. One site is the transient receptor potential vanilloid 1 cation channel (TRPV1). A useful endpoint for discriminating between TRPV1- or CB1-mediated effects of AM 404 is hypothermia. This is because TRPV1 or CB1 receptor activation produces a significant hypothermia in rats. The present study investigated the effects of AM 404 (1, 5, 10 and 20 mg/kg, i.p.) on body temperature in rats and the involvement of TRPV1 and CB1 receptors in the effects of AM 404. Doses of 10 and 20 mg/kg of AM 404 produced significant hypothermia. Pre-treatment with capsazepine (30 mg/kg, i.p.) blocked the hypothermia caused by 10 and 20 mg/kg of AM 404. Pre-treatment with SB 366791 (2 mg/kg, i.p.), a new TRPV1 antagonist, also abolished the hypothermia evoked by AM 404 (20 mg/kg, i.p.). In contrast, pre-treatment with SR 141716A (Rimonabant), a CB1 antagonist, or AA-5-HT, a fatty acid amide hydrolase (FAAH) blocker, did not affect AM 404-evoked hypothermia. The present data demonstrate that AM 404 evokes a significant hypothermia in rats that is dependent on TRPV1 receptor activation. [Copyright &y& Elsevier]

Abstract: The present study investigated a potential role for cannabinoid CB1 and CB2 receptors in capsaicin-evoked hypothermia. Capsaicin (1 mg/kg, s.c.) caused rapid and significant hypothermia in rats. Pretreatment with SR 141716A (1, 2.5 and 5 mg/kg, i.p.), a CB1 antagonist, or SR 144528 (1, 2.5 and 5 mg/kg, i.p.), a CB2 antagonist, did not affect capsaicin-induced hypothermia. In separate experiments, the hypothermia caused by WIN 55212-2 (5 mg/kg, i.m.), a cannabinoid agonist, was not significantly altered by capsazepine (10 and 30 mg/kg, i.p.) or SB 366791 (2 mg/kg, i.p.), a novel TRPV1 antagonist. These data suggest that capsaicin causes hypothermia by a CB1- and CB2-independent mechanism, and that WIN 55212-2 causes hypothermia by a TRPV1-independent mechanism. [Copyright &y& Elsevier]

In this work, ferrate(VI) was generated by the electrochemical oxidation of porous magnetite electrodes, made by melting pure magnetite grains. Pretreatment of the anode by cathodic polarization was necessary for ferrate(VI) generation and the achievement of high current efficiency. A electrolyte composition was found to be 16 M NaOH. In this electrolyte, the effect of anode current density J on Fe(VI) synthesis rate, current efficiency, and internal cell temperature were studied. An optimum result was obtained at J=3.3 mA cm-2, 30 °C in 16 M NaOH for 5 h. [Copyright &y& Elsevier]

The thermal decomposition of syngenite, K2Ca(SO4)2·H2O, formed during the treatment of liquid manure has been studied by thermal gravimetric analysis, differential scanning calorimetry, high temperature X-ray diffraction (XRD) and infrared emission spectroscopy (IES). Gypsum was found as a minor impurity resulting in a minor weight loss due to dehydration around 100 °C. The main endothermic dehydration and decomposition stage of syngenite to crystalline K2Ca2(SO4)3 and amorphous K2SO4 is observed around 200 °C. The reaction involves a solid-state re-crystallisation, while water and the K2SO4 diffuse out of the existing lattice. The additional weight loss steps around 250 and 350 °C are probably due to presence of larger syngenite particles, which exhibit slower decomposition due to the slower diffusion of water and K2SO4 out of the crystal lattice. A minor endothermic sulphate loss around 450 °C is not due to the decomposition of syngenite or its products or of the gypsum impurity. The origin of this sulphate is not clear. [Copyright &y& Elsevier]