A direct analysis method using sheath flow probe electrospray ionisation-mass spectrometry (sfPESI-MS) to detect drug residues from fingerprint forensic gel lifts.

Latent fingerprints at crime scenes are frequently recovered using forensic gel-lifters, which can help to preserve the crime scene and to enhance visualisation of traces such as blood or paint. In addition to providing fingerprint ridge detail, additional chemical information can also be recovered from gel lifts that may prove pertinent to an investigation. However, while DNA and metal ions have been shown to be able to be detected in gel-lifted fingerprints, the determination of other types of chemical information such as the presence of drugs in gel-lifted prints has not been previously shown. This study demonstrates the application of an ambient ionisation method, sheath flow probe electrospray ionisation-mass spectrometry (sfPESI-MS), to the direct analysis of gel-lifted fingerprints. A model drug compound (zolpidem) is successfully detected from gel-lifted prints from three different surface types: glass, metal, and paper. The surface activity-based separation associated with probe electrospray approaches is shown to resolve zolpidem ions from background phthalate species, significantly enhancing the response obtained from the gel-lifter. A depletion series experiment shows that the drug residue can be detected with up to 100% efficiency after eight consecutive contacts; however, detection efficiency drops to 20% after 30 contacts. The developed approach has potential application to analysis of historical gel-lifters to obtain additional chemical information.

Minority-group incubators and majority-group reservoirs support the diffusion of climate change adaptations.

Successful climate change adaptation depends on the spread and maintenance of adaptive behaviours. Current theory suggests that the heterogeneity of metapopulation structure can help adaptations diffuse throughout a population. In this paper, we develop an agent-based model of the spread of adaptations in populations with minority-majority metapopulation structure, where subpopulations learn more or less frequently from their own group compared to the other group. In our simulations, minority-majority-structured populations with moderate degrees of in-group preference better spread and maintained an adaptation compared to populations with more equal-sized groups and weak homophily. Minority groups act as incubators for an adaptation, while majority groups act as reservoirs for an adaptation once it has spread widely. This means that adaptations diffuse throughout populations better when minority groups start out knowing an adaptation, as Indigenous populations often do, while cohesion among majority groups further promotes adaptation diffusion. Our work advances the goal of this theme issue by developing new theoretical insights and demonstrating the utility of cultural evolutionary theory and methods as important tools in the nascent science of culture that climate change adaptation needs. This article is part of the theme issue 'Climate change adaptation needs a science of culture'.

The form of uncertainty affects selection for social learning.

Social learning is a critical adaptation for dealing with different forms of variability. Uncertainty is a severe form of variability where the space of possible decisions or probabilities of associated outcomes are unknown. We identified four theoretically important sources of uncertainty: temporal environmental variability; payoff ambiguity; selection-set size; and effective lifespan. When these combine, it is nearly impossible to fully learn about the environment. We develop an evolutionary agent-based model to test how each form of uncertainty affects the evolution of social learning. Agents perform one of several behaviours, modelled as a multi-armed bandit, to acquire payoffs. All agents learn about behavioural payoffs individually through an adaptive behaviour-choice model that uses a softmax decision rule. Use of vertical and oblique payoff-biased social learning evolved to serve as a scaffold for adaptive individual learning - they are not opposite strategies. Different types of uncertainty had varying effects. Temporal environmental variability suppressed social learning, whereas larger selection-set size promoted social learning, even when the environment changed frequently. Payoff ambiguity and lifespan interacted with other uncertainty parameters. This study begins to explain how social learning can predominate despite highly variable real-world environments when effective individual learning helps individuals recover from learning outdated social information.

Development of a rapid, in-situ analysis method using sheath-flow probe electrospray ionisation-mass spectrometry for the direct identification of cocaine metabolites in dried blood spots.

RATIONALE: Small amounts of biofluid samples are frequently found at crime scenes; however, existing gold standard methods such as LC-MS frequently require destructive extraction of the sample before a time-consuming analysis which puts strain on forensic analysis providers and can preclude further sample analysis. This study presents the application of sheath-flow probe electrospray ionization-mass spectrometry (sfPESI-MS) to the direct analysis of drug metabolites in dried blood spots (DBS) as a high throughput, minimally destructive alternative. METHODS: A rapid direct analysis method using a sfPESI ionisation source coupled to an Orbitrap Exactive mass spectrometer was applied to detect cocaine metabolites (benzoylecgonine, BZE, cocaethylene, CE, and ecgonine methyl ester, EME) from DBS. An optimisation study exploring the use of different chemical modifiers (formic acid and sodium acetate) in the sfPESI probe extraction solvent was conducted to enhance the sensitivity and reproducibility of the sfPESI-MS method. RESULTS: Optimisation of the extraction solvent significantly enhanced the sensitivity and reproducibility of the sfPESI-MS method. A quantitative response over a five-point calibration range 0.5 to 10 µg/ml was obtained for BZE (R2 = 0.9979) and CE (R2 = 0.9948). Limits of detection (LOD) of 1.31, 0.29 and 0.15 µg/ml were achieved for EME, BZE and CE, respectively, from 48 h aged DBSs with % RSD (relative standard deviation) across the calibration range ranging between 19%-28% for [BZE + H]+ , 13%-21% for [CE + H]+ and 12%-29% for [EME + H]+ . CONCLUSIONS: A rapid (< 20 s) quantitative method for the direct analysis of cocaine metabolites from DBS which requires no prior sample preparation was developed. Although the LOD achieved for BZE (LOD: 0.29 µg/ml) was above the UK threshold limit of exposure for drug driving (0.05 µg/ml), the method may be suitable for use in identifying overdose in forensic analysis.

Ultrafast transient absorption spectroelectrochemistry: femtosecond to nanosecond excited-state relaxation dynamics of the individual components of an anthraquinone redox couple.

Many photoactivated processes involve a change in oxidation state during the reaction pathway and formation of highly reactive photoactivated species. Isolating these reactive species and studying their early-stage femtosecond to nanosecond (fs-ns) photodynamics can be challenging. Here we introduce a combined ultrafast transient absorption-spectroelectrochemistry (TA-SEC) approach using freestanding boron doped diamond (BDD) mesh electrodes, which also extends the time domain of conventional spectrochemical measurements. The BDD electrodes offer a wide solvent window, low background currents, and a tuneable mesh size which minimises light scattering from the electrode itself. Importantly, reactive intermediates are generated electrochemically, via oxidation/reduction of the starting stable species, enabling their dynamic interrogation using ultrafast TA-SEC, through which the early stages of the photoinduced relaxation mechanisms are elucidated. As a model system, we investigate the ultrafast spectroscopy of both anthraquinone-2-sulfonate (AQS) and its less stable counterpart, anthrahydroquinone-2-sulfonate (AH2QS). This is achieved by generating AH2QS in situ from AQS via electrochemical means, whilst simultaneously probing the associated early-stage photoinduced dynamical processes. Using this approach we unravel the relaxation mechanisms occurring in the first 2.5 ns, following absorption of ultraviolet radiation; for AQS as an extension to previous studies, and for the first time for AH2QS. AQS relaxation occurs via formation of triplet states, with some of these states interacting with the buffered solution to form a transient species within approximately 600 ps. In contrast, all AH2QS undergoes excited-state single proton transfer with the buffered solution, resulting in formation of ground state AHQS- within approximately 150 ps.

Mechanistic modeling for the masses.

The generalizability crisis is compounded, or even partially caused, by a lack of specificity in psychological theories. Expanding the use of mechanistic models among psychologists is therefore important, but faces numerous hurdles. A cultural evolutionary approach can help guide and evaluate interventions to improve modeling efforts in psychology, such as developing standards and implementing them at the institutional level.

The Impact of a Graded Maximal Exercise Protocol on Exhaled Volatile Organic Compounds: A Pilot Study.

Exhaled volatile organic compounds (VOCs) are of interest due to their minimally invasive sampling procedure. Previous studies have investigated the impact of exercise, with evidence suggesting that breath VOCs reflect exercise-induced metabolic activity. However, these studies have yet to investigate the impact of maximal exercise to exhaustion on breath VOCs, which was the main aim of this study. Two-litre breath samples were collected onto thermal desorption tubes using a portable breath collection unit. Samples were collected pre-exercise, and at 10 and 60 min following a maximal exercise test (VO2MAX). Breath VOCs were analysed by thermal desorption-gas chromatography-mass spectrometry using a non-targeted approach. Data showed a tendency for reduced isoprene in samples at 10 min post-exercise, with a return to baseline by 60 min. However, inter-individual variation meant differences between baseline and 10 min could not be confirmed, although the 10 and 60 min timepoints were different (p = 0.041). In addition, baseline samples showed a tendency for both acetone and isoprene to be reduced in those with higher absolute VO2MAX scores (mL(O2)/min), although with restricted statistical power. Baseline samples could not differentiate between relative VO2MAX scores (mL(O2)/kg/min). In conclusion, these data support that isoprene levels are dynamic in response to exercise.

Covert signaling is an adaptive communication strategy in diverse populations.

Identity signals are those common components of communication transmissions that inform receivers of the signaler's membership in a categorizable subset of individuals. Such signals may be overt, broadcast to all possible receivers, or covert, encrypted so that only similar receivers are likely to perceive their identity-relevant meaning. Here we present an instrumental theory of covert signaling, based on the function of identity signals in social assortment. We argue that covert signaling is favored when signalers are generous toward strangers, when costs of being discovered as dissimilar are high, and when the ability to assort only with preferred partners is restricted. We further argue that covert signaling should be more common among members of "invisible" minorities, who are less likely to encounter similar individuals by chance. We formalize this theory with an evolutionary model to more rigorously explore the consequences of our assumptions. Our results have implications for our understanding of numerous aspects of social life, including communication, cooperation, social identity, humor, pragmatics, politics, hate speech, and the maintenance of diversity. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Subways and Urban Air Pollution.

We investigate the effect of subway system openings on urban air pollution. On average, particulate concentrations are unchanged by subway openings. For cities with higher initial pollution levels, subway openings reduce particulates by 4 percent in the area surrounding a city center. The effect decays with distance to city center and persists over the longest time horizon that we can measure with our data, about four years. For highly polluted cities, we estimate that a new subway system provides an external mortality benefit of about $1 billion per year. For less polluted cities, the effect is indistinguishable from zero. Back of the envelope cost estimates suggest that reduced mortality due to lower air pollution offsets a substantial share of the construction costs of subways.

Applications of ambient ionization mass spectrometry in 2021: An annual review.

Ambient ionization mass spectrometry (AIMS) has revolutionized the field of analytical chemistry, enabling the rapid, direct analysis of samples in their native state. Since the inception of AIMS almost 20 years ago, the analytical community has driven the further development of this suite of techniques, motivated by the plentiful advantages offered in addition to traditional mass spectrometry. Workflows can be simplified through the elimination of sample preparation, analysis times can be significantly reduced and analysis remote from the traditional laboratory space has become a real possibility. As such, the interest in AIMS has rapidly spread through analytical communities worldwide, and AIMS techniques are increasingly being integrated with standard laboratory operations. This annual review covers applications of AIMS techniques throughout 2021, with a specific focus on AIMS applications in a number of key fields of research including disease diagnostics, forensics and security, food safety testing and environmental sciences. While some new techniques are introduced, the focus in AIMS research is increasingly shifting from the development of novel techniques toward efforts to improve existing AIMS techniques, particularly in terms of reproducibility, quantification and ease-of-use.

Volatile atmospheric pressure chemical ionisation mass spectrometry headspace analysis of E. coli and S. aureus.

Identifying the characteristics of bacterial species can improve treatment outcomes and mass spectrometry methods have been shown to be capable of identifying biomarkers of bacterial species. This study is the first to use volatile atmospheric pressure chemical ionisation mass spectrometry to directly and non-invasively analyse the headspace of E. coli and S. aureus bacterial cultures, enabling major biological classification at species level (Gram negative/positive respectively). Four different protocols were used to collect data, three utilising discrete 5 min samples taken between 2 and 96 h after inoculation and one method employing 24 h continuous sampling. Characteristic marker ions were found for both E. coli and S. aureus. A model to distinguish between sample types was able to correctly identify the bacteria samples after sufficient growth (24-48 h), with similar results obtained across different sampling methods. This demonstrates that this is a robust method to analyse and classify bacterial cultures accurately and within a relevant time frame, offering a promising technique for both clinical and research applications.

Effects of substituent position on aminobenzoate relaxation pathways in solution.

The negative effects of ultraviolet radiation (UVR) on human skin have led to the widespread use of sunscreens, i.e. skincare products containing UV filters to absorb, reflect or otherwise block UVR. The mechanisms by which UV filters dissipate energy following photoexcitation, i.e. their photodynamics, can crucially determine a molecule's performance as a sunscreen UV filter. In this work, we evaluate the effects of substituent position on the in-solution relaxation pathways of two derivates of methyl anthranilate (an ortho compound that is a precursor to the UV filter meradimate), meta- and para-methyl anthranilate, m-MA and p-MA, respectively. The photodynamics of m-MA were found to be sensitive to solvent polarity: its emission spectra show larger Stokes shifts with increasing polarity, and both the fluorescence quantum yield and lifetimes for m-MA increase in polar solvents. While the Stokes shifts for p-MA are much milder and more independent of solvent environment than those of m-MA, we find its fluorescence quantum yields to be sensitive not only to solvent polarity but to the hydrogen bonding character of the solvent. In both cases (m- and p-MA) we have found common computational methods to be insufficient to appropriately model the observed spectroscopic data, likely due to an inability to account for explicit solvent interactions, a known challenge in computational chemistry. Therefore, apart from providing insight into the photodynamics of anthranilate derivatives, the work presented here also provides a case study that may be of use to theoretical chemists looking to improve and develop explicit solvent computational methods.

Exploring the Blueprint of Photoprotection in Mycosporine-like Amino Acids.

Microorganisms require protection against the potentially damaging effects of ultraviolet radiation exposure. Photoprotection is, in part, provided by mycosporine-like amino acids (MAAs). Previous reports have proposed that nonradiative decay mediates the impressive photoprotection abilities of MAAs. In this letter, we present the first ultrafast dynamics study of two MAAs, shinorine and porphyra-334. We demonstrate that, in aqueous solution, these MAAs relax along their S1 coordinates toward the S1/S0 conical intersection within a few hundred femtoseconds after photoexcitation and then traverse the conical intersection and vibrationally cool in approximately 1 ps through heat transfer to the solvent. This new insight allows a quintessential component of microbial life to be unraveled and informs the development of molecular photon-to-heat converters for a myriad of applications.

Towards developing novel and sustainable molecular light-to-heat converters.

Light-to-heat conversion materials generate great interest due to their widespread applications, notable exemplars being solar energy harvesting and photoprotection. Another more recently identified potential application for such materials is in molecular heaters for agriculture, whose function is to protect crops from extreme cold weather and extend both the growing season and the geographic areas capable of supporting growth, all of which could help reduce food security challenges. To address this demand, a new series of phenolic-based barbituric absorbers of ultraviolet (UV) radiation has been designed and synthesised in a sustainable manner. The photophysics of these molecules has been studied in solution using femtosecond transient electronic and vibrational absorption spectroscopies, allied with computational simulations and their potential toxicity assessed by in silico studies. Following photoexcitation to the lowest singlet excited state, these barbituric absorbers repopulate the electronic ground state with high fidelity on an ultrafast time scale (within a few picoseconds). The energy relaxation pathway includes a twisted intramolecular charge-transfer state as the system evolves out of the Franck-Condon region, internal conversion to the ground electronic state, and subsequent vibrational cooling. These barbituric absorbers display promising light-to-heat conversion capabilities, are predicted to be non-toxic, and demand further study within neighbouring application-based fields.

Reinvestigating the Photoprotection Properties of a Mycosporine Amino Acid Motif.

With the growing concern regarding commercially available ultraviolet (UV) filters damaging the environment, there is an urgent need to discover new UV filters. A family of molecules called mycosporines and mycosporine-like amino acids (referred to as MAAs collectively) are synthesized by cyanobacteria, fungi and algae and act as the natural UV filters for these organisms. Mycosporines are formed of a cyclohexenone core structure while mycosporine-like amino acids are formed of a cyclohexenimine core structure. To better understand the photoprotection properties of MAAs, we implement a bottom-up approach by first studying a simple analog of an MAA, 3-aminocyclohex-2-en-1-one (ACyO). Previous experimental studies on ACyO using transient electronic absorption spectroscopy (TEAS) suggest that upon photoexcitation, ACyO becomes trapped in the minimum of an S1 state, which persists for extended time delays (>2.5 ns). However, these studies were unable to establish the extent of electronic ground state recovery of ACyO within 2.5 ns due to experimental constraints. In the present studies, we have implemented transient vibrational absorption spectroscopy (as well as complementary TEAS) with Fourier transform infrared spectroscopy and density functional theory to establish the extent of electronic ground state recovery of ACyO within this time window. We show that by 1.8 ns, there is >75% electronic ground state recovery of ACyO, with the remaining percentage likely persisting in the electronic excited state. Long-term irradiation studies on ACyO have shown that a small percentage degrades after 2 h of irradiation, plausibly due to some of the aforementioned trapped ACyO going on to form a photoproduct. Collectively, these studies imply that a base building block of MAAs already displays characteristics of an effective UV filter.

Exploring the Photochemistry of an Ethyl Sinapate Dimer: An Attempt Toward a Better Ultraviolet Filter.

The photochemistry and photostability of a potential ultraviolet (UV) radiation filter, dehydrodiethylsinapate, with a broad absorption in the UVA region, is explored utilizing a combination of femtosecond time-resolved spectroscopy and steady-state irradiation studies. The time-resolved measurements show that this UV filter candidate undergoes excited state relaxation after UV absorption on a timescale of ~10 picoseconds, suggesting efficient relaxation. However, steady-state irradiation measurements show degradation under prolonged UV exposure. From a photochemical standpoint, this highlights the importance of considering both the ultrafast and "ultraslow" timescales when designing new potential UV filters.

Insights into the photoprotection mechanism of the UV filter homosalate.

Homosalate (HMS) is a salicylate molecule that is commonly included within commercial sunscreen formulations to provide protection from the adverse effects of ultraviolet (UV) radiation exposure. In the present work, the mechanisms by which HMS provides UV photoprotection are unravelled, using a multi-pronged approach involving a combination of time-resolved ultrafast laser spectroscopy in the gas-phase and in solution, laser-induced fluorescence, steady-state absorption spectroscopy, and computational methods. The unique combination of these techniques allow us to show that the enol tautomer of HMS undergoes ultrafast excited state intramolecular proton transfer (ESIPT) upon photoexcitation in the UVB (290-320 nm) region; once in the keto tautomer, the excess energy is predominantly dissipated non-radiatively. Sharp transitions are observed in the LIF spectrum at close-to-origin excitation energies, which points towards the potential presence of a second conformer that does not undergo ESIPT. These studies demonstrate that, overall, HMS exhibits mostly favourable photophysical characteristics of a UV filter for inclusion in sunscreen formulations.

Evidence for alternative exhaled elimination profiles of disinfection by-products and potential markers of airway responses to swimming in a chlorinated pool environment.

Chlorine-based disinfectants protect pool water from pathogen contamination but produce potentially harmful halogenated disinfection by-products (DBPs). This study characterized the bioaccumulation and elimination of exhaled DBPs post-swimming and investigated changes in exhaled breath profiles associated with chlorinated pool exposure. Nineteen participants provided alveolar-enriched breath samples prior to and 5, 90, 300, 510, and 600 minutes post-swimming. Known DBPs associated with chlorinated water were quantitated by thermal desorption-gas chromatography-mass spectrometry. Two distinct exhaled DBP elimination profiles were observed. Most participants (84%) reported peak concentrations immediately post-swimming that reduced exponentially. A sub-group exhibited a previously unobserved and delayed washout profile with peak levels at 90 minutes post-exposure. Metabolomic investigations tentatively identified two candidate biomarkers associated with swimming pool exposure, demonstrating an upregulation in the hours after exposure. These data demonstrated a hitherto undescribed exhaled DBP elimination profile in a small number of participants which contrasts previous findings of uniform accumulation and exponential elimination. This sub-group which exhibited delayed peak-exhaled concentrations suggests the uptake, processing, and immediate elimination of DBPs are not ubiquitous across individuals as previously understood. Additionally, non-targeted metabolomics highlighted extended buildup of compounds tentatively associated with swimming in a chlorinated pool environment that may indicate airway responses to DBP exposure.

Correction to 'Open science and modified funding lotteries can impede the natural selection of bad science'.

[This corrects the article DOI: 10.1098/rsos.190194.].

Open science and modified funding lotteries can impede the natural selection of bad science.

Assessing scientists using exploitable metrics can lead to the degradation of research methods even without any strategic behaviour on the part of individuals, via 'the natural selection of bad science.' Institutional incentives to maximize metrics like publication quantity and impact drive this dynamic. Removing these incentives is necessary, but institutional change is slow. However, recent developments suggest possible solutions with more rapid onsets. These include what we call open science improvements, which can reduce publication bias and improve the efficacy of peer review. In addition, there have been increasing calls for funders to move away from prestige- or innovation-based approaches in favour of lotteries. We investigated whether such changes are likely to improve the reproducibility of science even in the presence of persistent incentives for publication quantity through computational modelling. We found that modified lotteries, which allocate funding randomly among proposals that pass a threshold for methodological rigour, effectively reduce the rate of false discoveries, particularly when paired with open science improvements that increase the publication of negative results and improve the quality of peer review. In the absence of funding that targets rigour, open science improvements can still reduce false discoveries in the published literature but are less likely to improve the overall culture of research practices that underlie those publications.