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2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenylhydrazine (DNH) are harmful to the environment and human beings. Trace detection of TNP and DNH is worth of developing facile methods. In this work, cellulose powder and filter paper based fluorescence sensor are synthesized. Firstly, NH2CH2CH2– was introduced into cellulose through etherification reaction, and at the same time, a small molecule BODIPY with –CHO was synthesized. Then BODIPY was incorporated into cellulose by Schiff base reaction to obtain fluorescent macromolecular probes. These fluorescent cellulose sensors can efficiently identify TNP and DNH, with the lowest detection limits of 2.8 × 10−7 M and 1.6 × 10−7 M, respectively. Fluorescent filter paper is obtained via the same route. They also exhibit TNP and DNH identification ability. The method developed in filter paper not only expands the application range of cellulose, but also can efficiently identify the pollutants TNP and DNH, which is of great significance in theory and practical applications.

Organisms may respond to local stimuli that benefit or threaten their fitness. The adaptive movement behaviour may allow individuals to adjust their speed to maximise the chances of being in comfort zones, where death risk is minimal. We investigate spatial cyclic models where the rock-paper-scissors game rules describe the nonhierarchical dominance. We assume that organisms of one out of the species can control the mobility rate in response to the information obtained from scanning the environment. Running a series of stochastic simulations, we quantify the effects of the movement strategy on the spatial patterns and population dynamics. Our findings show that the ability to change mobility to adapt to environmental clues is not reflected in an advantage in cyclic spatial games. The adaptive movement provokes a delay in the spatial domains occupied by the species in the spiral waves, making the group more vulnerable to the advance of the dominant species and less efficient in taking territory from the dominated species. Our outcomes also show that the effects of adaptive movement behaviour accentuate whether most individuals have a long-range neighbourhood perception. Our results may be helpful for biologists and data scientists to comprehend the dynamics of ecosystems where adaptive processes are fundamental., Comment: 8 pages, 7 figures

A facile and cost-effective method was developed to create superhydrophobic surfaces onto a superhydrophilic commercial paper for the application of droplet splitting of microliter droplets into nano and sub-nano-liter droplets. The high wettability contrast of nearly 180° between the superhydrophobic region created via candle soot coated onto the patterned poly (dimethylsiloxane) and the paper causes the self-partitioning of a 1 µl droplet while sliding through the surface with a speed ranging from 0.001 to 7.3 mm/s. Additionally, the splitting of the droplet demonstrated for µl droplets of surface tension ranging from 72 mN/m to 38.5 mN/m. The plasmonic droplet assay for surface-enhanced Raman spectroscopy was fabricated via in-situ reduction of Ag nanoparticles onto the superhydrophilic region. The Raman scattering studies of methyl orange using the prepared substrates exhibit a limit of detection of 670 pM. Further, by using methyl orange as a probe molecule, selective detection of Hg2+ ions up to a concentration of 100 pM in nanoliter droplet volume is demonstrated. It is envisaged that these cost-effective plasmonic nanoliter droplet assays created via patterned superhydrophilic-superhydrophobic can find applications in high throughput screening, microfluidic bioassays, medical diagnosis.

In this work, the hydrothermal method is adopted to synthesize needle-like Co3O4 on the carbon fiber paper (CP) followed by the growth of nickel-manganese layered double hydroxide (Ni-Mn LDH) using the water bath method. Accordingly, the Ni-Mn LDH could be deposited onto the needle-like Co3O4 to form Ni-Mn LDH/Co3O4/CP composite electrode with a hierarchical structure. The electrochemical performance and the material properties are measured, and the influences of different concentrations of Ni(NO3)2∙6H2O, Mn(NO3)2∙4H2O on the performances of Ni-Mn LDH/Co3O4/CP are investigated. Based upon the results, it is concluded that although Co3O4 contributes some of the specific capacitance, Ni-Mn LDH and its uniform deposition on the Co3O4 surface play a key factor to enhance the specific capacitance. At a current density of 1 A/g, a specific capacitance of 219 F/g of the Co3O4/CP electrode is obtained, while an extremely high specific capacitance of 1327 F/g of the Ni-Mn LDH/Co3O4/CP electrode can be attained. In addition, the asymmetric supercapacitor which is built using the Ni-Mn LDH/Co3O4/CP electrode as the positive electrode and active carbon on CP electrode as the negative electrode, shown an energy density of 35.87 Wh/kg with a power density of 449.99 W/kg as well as a power density of up to 9000 W/kg and an energy density of 18.20 Wh/kg. By connecting two asymmetric supercapacitors in series, charging the supercapacitors for three seconds can light a 1.8 V red LED shine for 1320 sec, indicating that the as-synthesized composite electrode possessing outstanding potential can be used in supercapacitors.

For the important applications of gas identification related to specific diseases in healthcare, flexible gas sensors have attracted more attention. Among them, two-dimensional transition metal dichalcogenides (2D TMDs) have been known as good promising flexible gas-sensitive materials. While how to tightly attach 2D materials on flexible substrates is still challenging. Here, we propose an enhanced room-temperature flexible paper-substrate sensors based on 2D tungsten disulfide (WS2) with S defects, which are facilely synthesized by chemical exfoliation and vacuum filtration method. Structure characterization shows that most of the as-prepared 2D WS2 are within 3 layers. Spectroscopic characterization proves the existence of S defects on the surface of 2D WS2 produced by chemical exfoliation. The room-temperature (25 °C) NH3 gas sensitivity results show that the response intensity of 2D WS2 with rich S defects is nearly three times higher than the highly crystalline 2D WS2. The results of the flexible gas sensitivity indicate the fast response and high stability of our devices in breathing detection and bending experiments. Furthermore, the devices can effectively distinguish bending stress changes and gas-sensitive response signals at the same time, realizing multifunctional sensing detection. Our work will be a reference for fabricating flexible sensors based on 2D materials.

The authors of the title paper (J Photochem & Photobio A:Chem 393 (2020) 112413) claim to have synthesized a toluidine tartrate (TT) crystal and examined its nonlinear optical (NLO) behavior by experimental and theoretical studies. In this critique, it is shown that the so-called TT crystal is a surface degraded material and the experimental and theoretical data contradict literature reports on the 1:1 salt of p-toluidine and l -tartaric acid.

Room-temperature phosphorescence (RTP) materials have harvested enormous attention owing to their advanced optical properties, providing their possibility of the wider applications. Here, we designed a facile strategy to synthesize phosphorus and nitrogen co-doped carbon dots, while creatine provided the carbon and nitrogen source (CDs@creatine). Meanwhile, the as-prepared CDs@creatine exhibited the bright blue fluorescence in aqueous suspension, and showed the green RTP while being fixed on the filter paper. Significantly, the fluorescence of CDs@creatine was quenched by the introduction of warfarin, whereas their RTP was simultaneously enhanced. Specifically, their fluorescence reduction was mainly ascribed to static quenching effect (SQE) and inner filter effect (IFE). In addition, the abundant hydroxyl groups on the surface of CDs@creatine interacted with the carbonyl groups of warfarin to form hydrogen bonds which rigidified the excited triplet against the non-radiative transition, and thus leading to their enhanced phosphorescence. Therefore, a dual-channel detecting strategy of warfarin has been successfully proposed with the fluorescent linear range from 8 × 10−3 to 8 × 10−7 M and phosphorescent linear range of 2 × 10−5 to 1 × 10−8 M, which established a new way of assaying warfarin. Besides, CDs@creatine served as both fluorescent and phosphorescent ink, and were applied for painting and information encryption.

Water dispersible 3-marcaptoproponic acid protected Mn2+@ZnSe QDs were applied for sensing hazardous mercury and lead ions, which acts as an acceptor for metal ions due to the strong interaction between the metal ions and thiol group (-SH). The photoluminescence (PL) intensity of Mn2+@ZnSe QDs was strongly quenched with Hg2+ and Pb2+ (0-100 μL). The average PL lifetime of Mn2+@ZnSe was shortened with Hg2+ concentrations whereas increased with Pb2+ concentrations. A filter paper-based sensor was also prepared and successfully tested for sensing via colorimetric and fluorometric detection methods. The system provided a new possibility for dual response ions detection in real samples.

The past three decades have seen multiple reports of people with neurodegenerative disorders, or other forms of changes in their brains, who also show putative changes in how they approach and produce visual art. Authors argue that these cases may provide a unique body of evidence, so-called 'artistic signatures' of neurodegenerative diseases, that might be used to understand disorders, provide diagnoses, be employed in treatment, create patterns of testable hypotheses for causative study, and also provide unique insight into the neurobiological linkages between the mind, brain, body, and the human penchant for art-making itself. However-before we can begin to meaningfully build from such emerging findings, much less formulate applications-not only is such evidence currently quite disparate and in need of systematic review, almost all case reports and artwork ratings are entirely subjective, based on authors' personal observations or a sparse collection of methods that may not best fit underlying research aims. This leads to the very real question of whether we might actually find patterns of systematic change if fit to a rigorous review-Can we really 'read' art to illuminate possible changes in the brain? How might we best approach this topic in future neuroscientific, clinical, and art-related research? This paper presents a review of this field and answer to these questions. We consider the current case reports for seven main disorders-Alzheimer's and Parkinson's disease, frontotemporal and Lewy body dementia, corticobasal degeneration, aphasia, as well as stroke-consolidating arguments for factors and changes related to art-making and critiquing past methods. Taking the published artworks from these papers, we then conduct our own assessment, employing computerized and human-rater-based approaches, which we argue represent best practice to identify stylistic or creativity/quality changes. We suggest, indeed, some evidence for systematic patterns in art-making for specific disorders and also find that case authors showed rather high agreement with our own assessments. More important, through opening this topic and past evidence to a systematic review, we hope to open a discussion and provide a theoretical and empirical foundation for future application and research on the intersection of art-making and the neurotypical, the changed, and the artistic brain.

This review paper is devoted to study the conceptual difficulties that mathematics meets when attempting to describe the complexity of living matter focusing on the challenging perspective of developing a mathematical theory for living systems including mutations and selection. The quest starts with the identification of a number of common complexity features of living systems. Then, mathematical structures are derived to include these features, while mathematical models are derived by inserting in the structures models of individual based interactions. Three applications are examined by active particles methods, i.e., models of SARS2-CoV-2 pandemics, models of idiosyncratic learning in open markets and of the dynamics of prices accounting for human behaviors. A critical study, which pervades the whole paper, shows that also economics can be viewed as a behavioral science thus accounting for specific aspects typical of living systems.

In this paper, a unique one-dimensional double anti-PT-symmetric ring optical waveguide network (1D DAPTSROWN) is designed whose refractive index satisfies n ( x ) = − n ∗ ( − x ) . The extraordinary optical characteristics of the network are studied by means of the generalized Floquet-Bloch theorem, three-material network equation and generalized eigenfunction method. Due to the physical difference between the anti-PT-symmetric and PT-symmetric optical waveguide networks, the previous methond of the PT-symmetric optical waveguide network is not applicable to the anti-PT-symmetric optical waveguide network designed in this paper. Thus, based on the previous method and the network equation, we propose a connection function to identify the extremum mode points in the anti-PT-symmetric optical waveguide network. At the extremum mode point, the optical waveguide network can produce extraordinary ultra-strong transmission, ultra-strong reflection, and ultra-strong photonic localizations. The corresponding calculated values in this paper arrives at 1 0 28 , which is much larger than 1 0 12 (the best result reported previously). This shows that the anti-PT-symmetric network may have potential in applications in designing optical filters, optical amplifiers and so on.

In principle, this paper suggests powerful laser technology as a promising instrument that can be experimentally useful to control the lifetime and branching ratio for an unstable particle decay. In a recent paper [ arXiv:2101.00224 ], we calculated theoretically the W − -boson leptonic decay ( W − → l − ν l ) in the presence of a circularly polarized laser and we showed that the laser significantly contributed to the diminution of the leptonic decay rate. In this paper, as a continuation of the previous one, we mainly deal with the theoretical calculation of the W − -boson hadronic decay ( W − → q q ′ ) and we combine the analytical results obtained in both papers to examine the effect of an intense laser, in terms of its field strength and frequency, on the three measurable quantities in W − -boson decay (total decay rate, lifetime and branching ratios). It was found that the laser has notably contributed to the reduction of the total decay rate leading to a longer lifetime. Most importantly, the two branching ratios (one for leptons and the other for hadrons) are affected (increased or decreased) by the presence of a strong external electromagnetic field. Combined together, these two complementary works may provide an in-depth and comprehensive study that would be useful for any experimental investigation in the future.

This paper presents a numerical investigation of the laminar flow and pressure drop characteristics of planar Tee joints, a canonical flow of interest for the thermal-hydraulic design of oil-immersed power transformer windings. After formulating the problem in nondimensional form, the steady, constant property flow in planar 90 ∘ Tee joints is computed numerically by integrating the Navier–Stokes equations with fully developed upstream and downstream boundary conditions. The analysis assumes a straight-through configuration in which the straight duct holds flow in the same direction before and after the junction, whereas the flow in the side branch can either divide from the incoming flow or combine with it. The analysis starts with the description of the flow patterns that emerge in the dividing and combining cases for all mass split ratios, 0 ≤ m 1 ≤ 1 , and a wide range of straight duct to side branch width ratios, 1 ≤ α ≤ 3 , and Reynolds numbers of the common branch, 0 < Re3 ≤ 200, values that are representative of the cooling oil flow in oil-immersed transformer winding. Flow maps for planar Tee joints are then presented, showing the existence of different regions in the (Re3, m 1 )-plane that exhibit different number and location of recirculation zones. Pressure distributions and secondary loss coefficients are then computed and analyzed, providing a numerical database that is used to develop new local pressure loss correlations for planar Tee joints in an accompanying paper.

Inspired by the principles of Medical Physics 3.0, this paper frames a new model of clinical physics practice, anchored to clinical realities, clinical priorities, and advanced physics. The model is based on the conviction that the physicist is vested with the expertise and the responsibility to ensure each patient gets the optimum imaging exam towards the best clinical outcome. Key expectations and activities are encapsulated into 12 areas: scientific perspective, quality and safety assurance, regulatory compliance, technology assessment, use optimization, performance monitoring, technology acquisition, technology commissioning, vendor cooperation, translational practice, research consultancy, and technology education. The paper further highlights key challenges to effective clinical physics practice of increased scope of competency, balancing rigor and relevance, managing metrological surrogates of quality and safety, and integrating principle- and data-informed approaches. Mindful to practically mitigate these challenges, clinical imaging physics can play an essential role to enable evidence-based imaging care.

Gupta et al. (2020) had obtained a nontrivial solution for the Chaplygin gas equations and the generalized Riemann problem for the Chaplygin gas equations was solved by them through a rarefaction wave. In this paper, we explain that the existence of a rarefaction wave is not possible and that the solution obtained in Gupta et al. (2020) is also in error. In fact, in this paper, we solved the generalized Riemann problem through a characteristic shock(s). For several classes of non-constant and smooth initial data, the solution to the generalized Riemann problem is presented.

This paper proves a linear algebra result that has to do with the geometry of "widgets". For us a widget is a collection of n pairs of points in a vector space. (The pairs represent the different possible spin states of a particle.) We investigate linear relations among such collections. A corollary of our theorem was conjectured in arXiv:2208.02478v1 where it arose in an attempt to understand some issues in super string theory. In that paper an investigation of perturbative superstring theory with Ramond punctures required the special case when the ambient dimension is n. Here we prove the general case., Comment: 3 pages

In the present paper, discussion of the canonical quantization of a weakly nonideal Bose gas at zero temperature within the framework of the Bogolyubov approach is continued. Contrary to the previous paper on this subject, here the two-body interaction potential is considered in the general form. It is shown that in such a case consideration of the first nonlinear correction also leads to the automatic particle number conservation without any additional assumptions or modification of the resulting effective Hamiltonian., 30 pages. Supplementary material: the standard Maxima .wxmx file is automatically unpacked by the arXiv upload software, so the .xml file, which can also be processed by Maxima, is uploaded instead. v2: major revision of the text, added references, minor corrections in ancillary files. v3: typos corrected