College of Science and Engineering CSE publications Recent publications in Physical Sciences

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Recent publications in Physical Sciences

Brice, Sara M., Doma, Kenji, and Spratford, Wayne (2022) Effect of footwear on the biomechanics of loaded back squats to volitional exhaustion in skilled lifters. Journal of Strength and Conditioning Research. (In Press)
This study examined whether footwear influences the movement dynamics of barbell back squats to volitional exhaustion in experienced lifters. Eleven men (1 repetition maximum [1RM] = 138 ± 19 kg; 1RM % body mass = 168 ± 18%) performed 3 sets (5–12 ± 4 repetitions per set) of loaded barbell back squats to volitional exhaustion using raised-heel and flat-heel footwear. Barbell motion as well as moments, angles, angular velocity, and power in the sagittal plane at the ankle, knee, hip, and lumbopelvis were examined during the second repetition of the first set (Tsecond) and the final repetition of the third set (Tfinal). There were significant reductions (p < 0.05) in lower-limb concentric angular velocity and power output for both footwear conditions. For the raised-heel condition at Tfinal, hip and knee concentric angular velocities were significantly slower (p < 0.05), and knee concentric power output was significantly less (p < 0.05) compared with the flat-heel condition. A reduction in barbell velocity was not observed for the raised-heel condition despite there being reduction in hip and knee angular velocities. Furthermore, no differences were identified in lower-limb joint moments or any of the biomechanical characteristics of the lumbopelvis between the footwear conditions. The findings of this study suggest that neither type of footwear reduced joint loading or improved joint range-of-motion.

Jiang, Chunbo, Zheng, Lianxi, and Liu, Yang (2022) Aligned carbon nanotube films for immobilization of glucose oxidase and its application in glucose biosensor. Australian Journal of Chemistry, 75 (2). pp. 89-93.
Glucose oxidase (GOx) was immobilized between aligned carbon nanotube films (ACNTFs) using a cross-stackingmethod without any purification and functionalization processes. Direct electron transfer of GOx was achieved on theACNTFs with reversible redox peaks observed at the formal potential of –0.448 V. When applied to the determination ofglucose by cyclic voltammetry, the prepared enzymatic electrode exhibited a linear range from 1 to 5 mM under mediator-free physiological conditions, which makes it a promising candidate for the development of third-generation glucosebiosensors.

Van Irsel, Jurrian, Frauendorf, Magali, Ens, Bruno, Van De Pol, Martijn, Troost, Karen, Oosterbeek, Kees, De Kroon, Hans, Jongejans, Eelke, and Allen, Andrew M. (2022) State-dependent environmental sensitivity of reproductive success and survival in a shorebird. Ibis. (In Press)
To understand the consequences of anthropogenic and environmental changes for wildlife populations, it is important to study how individuals differ in their sensitivity to environmental change, and whether this depends on individual characteristics. An individual’s reproductive performance may provide an integrative, unidimensional proxy of an individual’s characteristics. In this study, we define an individual’s characteristics by three such reproductive states, namely successful-, failed-, and non-breeders in the previous year. We used a 16-year dataset of individually marked breeding Eurasian Oystercatchers Haematopus ostralegus to examine the inter-annual fluctuations in reproductive success and survival among breeding states, and their state-dependent sensitivity to environmental conditions. Environmental conditions included available biomass of the main prey species of breeding Oystercatchers (Ragworm, Baltic Tellin and Lugworm), tidal height which reflects one of the main causes of nest loss (flooding) and conditions that may impact the energetic requirements during incubation, such as temperature. We also included environmental variables measured in winter, including available biomass of the main winter prey species (Blue Mussel and Common Cockle) along with factors that may affect food availability and energetic requirements for homeostasis, namely bivalve weight loss, windchill, winter severity, and precipitation. Breeding birds that were successful the previous year had higher survival, and were more likely to remain successful, than failed- and non-breeders. The effects of environmental conditions acted in the same direction on reproductive success but had opposite effects on survival among the three breeding states, especially for windchill and Blue Mussel biomass. The contrasting state-dependent effects of the environment on survival thus averaged out when examining consequences for lifetime reproductive nest success (LRnS); instead LRnS was largely influenced by environmental conditions acting upon reproduction. Our study indicates that an individual’s previous breeding state provides an integrative measure of heterogeneity in individuals’ sensitivity of reproduction and survival to environmental change. Incorporating previous breeding state as a source of individual heterogeneity in population modelling may improve predictions of future population dynamics in a rapidly changing world.

Van Der Kolk, Henk-Jan, Ens, Bruno J., Oosterbeek, Kees, Jongejans, Eelke, and van de Pol, Martijn (2022) The hidden cost of disturbance: Eurasian Oystercatchers (Haematopus ostralegus) avoid a disturbed roost site during the tourist season. Ibis, 164 (2). pp. 437-450.
Disturbance may impact individual birds and ultimately bird populations. If animals avoid disturbed sites this may prevent them from being disturbed directly but may also negatively impact their movement patterns and energy budgets. Avoidance is, however, challenging to study, because it requires following individuals over large spatial scales in order to compare their movement rates between sites in relation to spatiotemporal variation in disturbance intensity. We studied how 48 GPS-tracked non-breeding Eurasian Oystercatchers Haematopus ostralegus used two neighbouring roost sites in the Wadden Sea. One roost site is highly influenced by seasonal recreational disturbance whereas the other is an undisturbed sandbar. We analysed roost choice and the probability of moving away from the disturbed roost site with regard to a seasonal recreation activity index, weekends and night-time. Oystercatchers often chose to roost on the undisturbed site, even if they were foraging closer to the disturbed roost. The probability that Oystercatchers chose to roost on the disturbed site was negatively correlated with the recreation activity index and was lowest in the tourist season (summer and early autumn), indicating that birds used the site less often when recreation levels were high. Furthermore, the probability that birds moved away from the disturbed site during high tide was positively correlated with the recreation activity index. The choice to roost on the undisturbed site implies that birds must fly an additional 8 km during one high-tide period, which equates to 3.4% of daily energy expenditure of an average Oystercatcher. Our study tentatively suggests that the costs of avoidance may outweigh the energetic cost of direct flight responses and hence that avoidance of disturbed sites requires more attention in future disturbance impact studies. Nature managers should evaluate whether high-quality undisturbed roosting sites are available near foraging sites, and in our case closing of a section of the disturbed site during high tides in the tourist season may mitigate much disturbance impact.

Whittingham, Ian B. (2022) Scattering of low energy neutrinos and antineutrinos by atomic electrons. Physical Review D, 105 (1). 013008.
Studies of neutrino mixing and oscillations, solar neutrinos as background in dark matter searches involving electron detection, detection of sterile neutrino warm dark matter, and of possible electromagnetic properties of neutrinos, have generated interest in the low energy O(10 keV) scattering of electron neutrinos and antineutrinos by atomic electrons where the binding of the atomic electron cannot be ignored. Of particular interest is the ionization of atoms by neutrinos and antineutrinos. Most existing calculations are based upon modifications of the free electron differential cross section which destroy the relationship between the neutrino helicities and the orbital and spin angular momenta of the atomic electrons. The present calculations maintain the full collision dynamics by formulating the scattering in configuration space using the Bound Interaction Picture, rather than the usual formulation in the Interaction Picture in momentum space as appropriate to scattering by free electrons. Energy spectra of ionization electrons produced by scattering of neutrinos and antineutrinos with energies of 5, 10, 20, and 30 keV by hydrogen, helium and neon have been calculated using Dirac central field eigenfunctions, and are presented as ratios to the spectra for scattering by free electrons. Binding effects increase strongly with atomic number, are largest for low neutrino energy and, for each neutrino energy, greatest at the high electron energy end of the spectrum. The most extreme effects of binding are for 5 keV scattering by Ne where the ratios are less than 0.1. The energy spectra have been calculated for both a Coulombic final electron state and a free final electron state. The results indicate that the binding effects from the continuum state of the final electron are significant and can be comparable to those arising from the bound initial electron state.

Cavalieri, Jo, and Das, Sourav (2022) Modification of a GnRH-based system to synchronise oestrus in Bos indicus cattle improves pregnancy rates to AI in heifers but not cows. Australian Veterinary Journal, 100 (4). pp. 162-171.
Objective: To investigate if modification of a gonadotrophin-releasing hormone (GnRH) based protocol to synchronise oestrus in Bos indicus cattle will improve response rates to the first administration of GnRH and improve pregnancy rates to artificial insemination (AI). Design: Randomised control study. Methods: Bos indicus heifers, nonlactating and lactating cows allocated to a GnRH-18 treatment (n = 237) were treated with an intravaginal device (IVD) and cloprostenol (0.5 mg IM) on day −11 and on day 0 remaining animals in the GnRH-7 treatment (n = 222) were administered an IVD and every animal was treated with GnRH (100 μg IM). On day 7, equine chorionic gonadotrophin (400 IU IM) and cloprostenol were administered and IVD's were removed. Animals detected in oestrus on day 9 were artificially inseminated while those not detected in oestrus were administered GnRH (100 μg IM) at 1700 hours and inseminated on day 10. Bulls were inserted 2 weeks after completion of AI and remained until day 65. Results: The GnRH-18 protocol increased the diameter of the largest follicle in the ovary on day 0, increased the percentage of new CL's induced after day 0 (46.3% vs 36.1%, for GnRH-18 and GnRH-7; P = 0.022), decreased circulating concentrations of progesterone on day 7 and increased odds of pregnancy to AI in heifers but not in nonlactating and lactating cows. Conclusion: Treatment with the GnRH-18 compared to the GnRH-7 protocol increased pregnancy rates to AI in heifers but not in nonlactating or lactating cows.

Lei, Peng, Zhou, Ying, Li, Bei, Liu, Yang, Dong, Chuan, and Shuang, Shaomin (2022) Gold/palladium–polypyrrole/graphene nanocomposites for simultaneous electrochemical detection of DNA bases. ACS Applied Nano Materials, 5 (1). pp. 1635-1643.
The unique combination of DNA bases is essential for storing genetic information. A reliable and accurate electrochemical sensor based on a gold/palladium−polypyrrole/graphene nanocomposite (Au/Pd−PPy/GR) has been prepared to individually and simultaneously detect guanine (G), adenine (A), thymine (T), and cytosine (C). The bimetallic nanomaterial (Au/Pd−PPy) is used to enhance the sensing performance of DNA bases, and the GR could further increase the electroactive area and amplify the electrochemical response. As expected, the electrochemical sensor shows excellent electrocatalytic activity with well-separated current responses at 0.704 V (G), 0.976 (A), 1.164 (T), and 1.348 V (C). The prepared sensor exhibits the linear range of 1−350 μM for G, 5−300 μM for A, 20−900 μM for T, and 10−700 μM for C. The developed device is also demonstrated as an excellently sensitive and highly selective sensor to identify the four bases in calf thymus DNA, which provides the application of electrochemical sensors in bioscience.

Binks, Oliver, Cernusak, Lucas A., Liddell, Michael, Bradford, Matt, Coughlin, Ingrid, Carle, Hannah, Bryant, Callum, Dunn, Elliot, Oliveira, Rafael, Mencuccini, Maurizio, and Meir, Patrick (2022) Forest system hydraulic conductance: partitioning tree and soil components. New Phytologist, 233 (4). pp. 1667-1681.
Soil–leaf hydraulic conductance determines canopy–atmosphere coupling in vegetation models, but it is typically derived from ex-situ measurements of stem segments and soil samples. Using a novel approach, we derive robust in-situ estimates for whole-tree conductance (ktree), ‘functional’ soil conductance (ksoil), and ‘system’ conductance (ksystem, water table to canopy), at two climatically different tropical rainforest sites. Hydraulic ‘functional rooting depth’, determined for each tree using profiles of soil water potential (Ψsoil) and sap flux data, enabled a robust determination of ktree and ksoil. ktree was compared across species, size classes, seasons, height above nearest drainage (HAND), two field sites, and to alternative representations of ktree; ksoil was analysed with respect to variations in site, season and HAND. ktree was lower and changed seasonally at the site with higher vapour pressure deficit (VPD) and rainfall; ktree differed little across species but scaled with tree circumference; rsoil (1/ksoil) ranged from 0 in the wet season to 10× less than rtree (1/ktree) in the dry season. VPD and not rainfall may influence plot-level k; leaf water potentials and sap flux can be used to determine ktree, ksoil and ksystem; Ψsoil profiles can provide mechanistic insights into ecosystem-level water fluxes.

Guo, Zhifang, Blair, Victoria L., Deacon, Glen B., and Junk, Peter C. (2022) Europium is different: solvent and ligand effects on oxidation state outcomes and C-F activation in reactions between europium metal and Pentafluorophenylsilver. Chemistry: a European journal, 28 (3). e202103865.
Unique outcomes have emerged from the redox transmetallation/ protolysis (RTP) reactions of europium metal with [Ag(C6F5)(py)] (py=pyridine) and pyrazoles (RR ' pzH). In pyridine, a solvent not normally used for RTP reactions, the products were mainly Eu-II complexes, [Eu(RR ' pz)(2)(py)(4)] (RR ' pz=3,5-diphenylpyrazolate (Ph(2)pz) 1; 3-(2-thienyl)-5-trifluoromethylpyrazolate (ttfpz) 2; 3-methyl-5-phenylpyrazolate (PhMepz) 3). However, use of 3,5-di-tert-butylpyrazole (tBu(2)pzH) gave trivalent [Eu(tBu(2)pz)(3)(py)(2)] 4, whereas the bulkier N,N '-bis(2,6-difluorophenyl)formamidine (DFFormH) gave divalent [Eu(DFForm)(2)(py)(3)] 5. In tetrahydrofuran (thf), the usual solvent for RTP reactions, C-F activation was observed for the first time with [Ag(C6F5)(py)] in such reactions. Thus trivalent [{Eu-2(Ph(2)pz)(4)(py)(4)(thf)(2)(mu-F)(2)}{Eu-2(Ph(2)pz)(4)(py)(2)(thf)(4)(mu-F)(2)}] (6), [Eu-2(ttfpz)(4)(py)(2)(dme)(2)(mu-F)(2)] (7), [Eu-2(tBu(2)pz)(4)(dme)(2)(mu-F)(2)] (8) were obtained from the appropriate pyrazoles, the last two after crystallization from 1,2-dimethoxyethane (dme). Surprisingly 3,5-dimethylpyrazole (Me(2)pzH) gave the divalent cage [Eu-6(Me(2)pz)(10)(thf)(6)(mu-F)(2)] (9). This has a compact ovoid core held together by bridging fluoride, thf, and pyrazolate ligands, the last including the rare mu(4)-1 eta(5)(N2C3): 2 eta(2)(N,N '): 3 kappa(N): 4 kappa(N ') pyrazolate binding mode. With the bulky N,N '-bis(2,6-diisopropylphenyl)formamidine (DippFormH), which often favours C-F activation in RTP reactions, neither oxidation to Eu-III nor C-F activation was observed and [Eu(DippForm)(2)(thf)(2)] (10) was isolated. By contrast, Eu reacted with Bi(C6F5)(3) and Ph(2)pzH or tBu(2)pzH in thf without C-F activation, to give [Eu(Ph(2)pz)(2)(thf)(4)] (11) and [Eu(tBu(2)pz)(3)(thf)(2)] (12) respectively, the oxidation state outcomes corresponding to that for use of [Ag(C6F5)(py)] in pyridine.

Frauendorf, Magali, Allen, Andrew M., Jongejans, Eelke, Ens, Bruno J., Teunissen, Wolf, Kampichler, Christian, van Turnhout, Chris A.M., Bailey, Liam, de Kroon, Hans, Cremer, Jenny, Kleyheeg, Erik, Nienhuis, Jeroen, and van de Pol, Martijn (2022) Love thy neighbour?-Spatial variation in density dependence of nest survival in relation to predator community. Diversity and Distributions, 28 (4). pp. 624-635.
Aim: In many species, density-dependent effects on reproduction are an important driver of population dynamics. However, it is rarely considered that the direction of density dependence is expected to vary over space and time depending on anti-predator behaviour and predator community. Aggregation may allow for effective group mobbing against avian nest predators while aggregation may also attract mammalian predators, causing negative density dependence. We aim to quantify spatial variation in the effect of conspecific breeding density on nest survival in a mobbing bird species (Eurasian oystercatcher; Haematopus ostralegus) and identify whether this variation in density dependence can be explained by the predator community. Location: Country-wide (The Netherlands). Methods: We integrated reproductive data with breeding territory maps of Eurasian oystercatchers and occupancy maps of avian and mammalian predator species across the Netherlands for a 10-year period. Results: Spatial variation in the composition of the predator community explained the effects of neighbour density, showing decreasing nest survival when both conspecific density and mammalian dominance increased. Also, heterospecific density (from breeding godwits and lapwing) has an additional effect on the oystercatcher nest survival. Strikingly, this pattern did not extend to mammal-free island populations. Main conclusions: Our study provides evidence that both the strength and sign of density dependence can vary spatially within species, implying that it is dangerous to generalize results from a single local population to large-scale management implications and modelling exercises. The study also suggests that conservation actions that aim to attract breeding birds should be prioritized in areas with fewer mammalian predators, but this idea requires further testing on island populations.

Das, Sourav, Sheth, Arshay Nimish, Bansal, Priya, Chuah, Joon, and Wasson, Robert (2022) A statistical comparison of flood-related economic damage in Indian states with reflections on policy implications. International Journal of Disaster Risk Reduction, 72. 102835.
Economic damage caused by floods in India is a serious problem that has disrupted development and the fight against poverty in some parts of the country. It is therefore important to mitigate the effects of floods as effectively as possible. An analysis of aggregated economic damage in the categories of crops, housing and utilities in six Indian States from 1953 to 2011 is presented using rigorous statistical methods. The main result is that increasing mitigation efforts since Independence have not produced a monotically decreasing long term trend in damage, although the magnitude of reduction cannot be known precisely, based on publicly available data. Andhra Pradesh has the highest total damage followed by Bihar, West Bengal, Orissa, Assam, and Gujarat. The reasons for this ranking are unclear because the only publicly available proxy for potential damage, has a weak statistical effect. Similarities in damage between some States suggest that inter-State learning may be of value despite differences in hydrology, landscape and economic activity. Despite the deficiencies in the data and its spatial resolution, there is sufficient evidence to inspire new thinking and action about flood mitigation in India, for which District and Taluk level data will be essential.

Brice, Sara, Millett, Emma L., and Philippa, Bronson (2022) The validity of using inertial measurement units to monitor the torso and pelvis sagittal plane motion of elite rowers. Journal of Sports Sciences, 40 (8). pp. 950-958.
In elite sport, inertial measurement units (IMUs) are being used increasingly to measure movement in-field. IMU data commonly sought are body segment angles as this gives insights into how technique can be altered to improve performance and reduce injury risk. The purpose of this was to assess the validity of IMU use in rowing and identify if IMUs are capable of detecting differences in sagittal torso and pelvis angles that result from changes in stroke rates. Eight elite female rowers participated. Four IMUs were positioned along the torso and over the pelvis of each athlete. Reflective markers surrounded each IMU which were used to compute gold-standard data. Maxima, minima, angle range and waveforms for ten strokes at rates of 20, 24, 28 and 32 strokes per minute were analysed. Root mean square errors as a percentage of angle range fell between 1.44% and 8.43%. In most cases when significant differences (p < 0.05) in the angles were detected between stroke rates, this was observed in both IMU and gold-standard angle data. These findings suggest that IMUs are valid for measuring torso and pelvis angles when rowing and are capable of detecting differences that result from changes in stroke rate.

Allen, Andrew M., Jongejans, Eelke, van de Pol, Martijn, Ens, Bruno J., Frauendorf, Magali, van der Sluijs, Martijn, and de Kroon, Hans (2022) The demographic causes of population change vary across four decades in a long-lived shorebird. Ecology, 103 (4). e3615.
Understanding which factors cause populations to decline begins with identifying which parts of the life cycle, and which vital rates, have changed over time. However, in a world where humans are altering the environment both rapidly and in different ways, the demographic causes of decline likely vary over time. Identifying temporal variation in demographic causes of decline is crucial to assure that conservation actions target current and not past threats. However, this has rarely been studied as it requires long time series. Here we investigate how the demography of a long-lived shorebird (the Eurasian Oystercatcher Haematopus ostralegus) has changed in the past four decades, resulting in a shift from stable dynamics to strong declines (−9% per year), and recently back to a modest decline. Since individuals of this species are likely to respond differently to environmental change, we captured individual heterogeneity through three state variables: age, breeding status, and lay date (using integral projection models). Timing of egg-laying explained significant levels of variation in reproduction, with a parabolic relationship of maximal productivity near the average lay date. Reproduction explained most variation in population growth rates, largely due to poor nest success and hatchling survival. However, the demographic causes of decline have also been in flux over the last three decades: hatchling survival was low in the 2000s but improved in the 2010s, while adult survival declined in the 2000s and remains low today. Overall, the joint action of several key demographic variables explain the decline of the oystercatcher, and improvements in a single vital rate cannot halt the decline. Conservations actions will thus need to address threats occurring at different stages of the oystercatcher's life cycle. The dynamic nature of the threat landscape is further supported by the finding that the average individual no longer has the highest performance in the population, and emphasizes how individual heterogeneity in vital rates can play an important role in modulating population growth rates. Our results indicate that understanding population decline in the current era requires disentangling demographic mechanisms, individual variability, and their changes over time.

Sinyeue, Cynthia, Matsui, Mariko, Oelgemöller, Michael, Brégier, Frédérique, Chaleix, Vincent, Sol, Vincent, and Lebouvier, Nicolas (2022) Synthesis and investigation of flavanone derivatives as potential new anti-inflammatory agents. Molecules, 27. 1781.
Flavonoids are polyphenols with broad known pharmacological properties. A series of 2,3-dihydroflavanone derivatives were thus synthesized and investigated for their anti-inflammatory activities. The target flavanones were prepared through cyclization of 2'-hydroxychalcone derivatives, the later obtained by Claisen–Schmidt condensation. Since nitric oxide (NO) represents an important inflammatory mediator, the effects of various flavanones on the NO production in the LPS-induced RAW264.7 macrophage were assessed in vitro using the Griess test. The most active compounds were flavanone (4G), 20-carboxy-5,7-dimethoxy-flavanone (4F), 40-bromo 5,7-dimethoxy-flavanone (4D), and 20-carboxyflavanone (4J), with IC50 values of 0.603, 0.906, 1.030, and 1.830 microg/mL, respectively. In comparison, pinocembrin achieved an IC50 value of 203.60 microg/mL. Thus, the derivatives synthesized in this work had a higher NO inhibition capacity compared to pinocembrin, demonstrating the importance of pharmacomodulation to improve the biological potential of natural molecules. SARs suggested that the use of a carboxyl-group in the meta-position of the B-ring increases biological activity, whereas compounds carrying halogen substituents in the para-position were less active. The addition of methoxy-groups in the meta-position of the A-ring somewhat decreased the activity. This study successfully identified new bioactive flavanones as promising candidates for the development of new anti-inflammatory agents.

Kamel, Michael S.A., Oelgemöller, Michael, and Jacob, Mohan V. (2022) Sustainable plasma polymer encapsulation materials for organic solar cells. Journal of Materials Chemistry A, 10 (9). pp. 4683-4694.
The rapid degradation of organic photovoltaics (OPVs) under ambient conditions represents a major limitation to this promising technology. Device encapsulation is an effective approach to increase the lifetime of OPVs. Herein, we report the time and cost-effective synthesis of ultrathin encapsulation materials for OPVs by radio frequency (RF) plasma polymerization from plant extract. The encapsulated device retained 66% and 87% of its initial power conversion efficiency (PCE) and fill factor, respectively, after 90 days under ambient conditions while the reference device degraded within the first month. More interestingly, the open circuit voltage of the encapsulated device was found unchanged after >4.5 months with 70% of its original short circuit current density. The investigated thin films have shown strong absorption in the ultraviolet (UV) range with high transmission exceeding 98% to visible light and can be employed to prevent harmful UV photons from reaching the photoactive layer of the device. Additionally, the synthesized films have revealed a high chemical stability under artificial UV irradiation. Thus, this work presents a solvent-free and room temperature encapsulation method based on sustainable materials to increase the lifetime of OPVs without altering the device performance.

Mclean, Nina, Kruuk, Loeske E.B., Van Der Jeugd, Henk P., Leech, David, van Turnhout, Chris A.M., and van de Pol, Martijn (2022) Warming temperatures drive at least half of the magnitude of long-term trait changes in European birds. Proceedings of the National Academy of Sciences of the United States of America, 119 (10). e2105416119.
Many wild populations are experiencing temporal changes in life-history and other phenotypic traits, and these changes are frequently assumed to be driven by climate change rather thannonclimatic drivers. However, this assumption relies on three conditions: that local climate is changing, traits are sensitive to climate variability, and other drivers are not also changing over time. Although many studies acknowledge one or more of these conditions, all three are rarely checked simultaneously. Consequently, the relative contribution of climate change to trait change, and the variation in this contribution across traits and species, remain unclear. We used long-term datasets on 60 bird species in Europe to test the three conditions in laying date, offspring number, and body condition and used a method that quantifies the contribution of warming temperatures to changes in traits relative to other effects. Across species, approximately half of the magnitude of changes in traits could be attributed to rising mean temperature,suggesting that increasing temperatures are likely the single most important contributor to temporal trends and emphasizes the impact that global warming is having on natural populations. There were also substantial nontemperature-related temporal trends (presumably due to other changes such as urbanization), which generally caused trait change in the same direction as warming. Attributing temporal trends solely to warming thus overestimates the impact of warming. Furthermore, contributions from nontemperature drivers explained most of the interspecificvariation in trait changes, raising concerns about comparative studies that attribute differences in temporal trends to species differences in climate-change sensitivity.

Shephard, Angus C.G., Daniels, Daisy P., Deacon, Glen B., Guo, Zhifang, Jaroschik, Florian, and Junk, Peter C. (2022) Selective carbon-phosphorus bond cleavage: expanding the toolbox for accessing bulky divalent lanthanoid sandwich complexes. Chemical Communications, 58. pp. 4344-4347.
The synthesis of two new tetra- and penta-phenycyclopentadienyldiphenylphosphine pro-ligands which readily undergo selective C–P bond cleavage has allowed for the facile synthesis of bulky divalent octa- and deca-phenylmetallocenes of europium, ytterbium and samarium.

Liu, Yang, Moshrefi, Reza, Rickard, William D.A., Scanlon, Micheál D., Stockmann, T. Jane, and Arrigan, Damien W.M. (2022) Ion-transfer electrochemistry at arrays of nanoscale interfaces between two immiscible electrolyte solutions arranged in hexagonal format. Journal of Electroanalytical Chemistry, 909. 116113.
The electrochemical behaviour of hexagonally arranged nanopore arrays was studied by simple ion transfer across the interface between two immiscible electrolyte solutions (ITIES) formed between water and 1,2-dichloroethane. The hexagonal nanoITIES arrays were supported at nanopores fabricated by focused ion beam milling into 50 nm thick silicon nitride films. Six arrays with different pore centre-to-centre distance (rc) to radius (ra) ratios were prepared. Within these arrays, the diffusion-limited steady-state currents (iss) of tetrapropylammonium cation (TPrA+) ion transfer increased concomitantly with increasing rc/ra ratio, reaching a plateau at rc/ra ≥ 96, which is greater than that previously reported for square-patterned nanoITIES arrays (rc/ra ≥ 56). The diffusion regime and iss associated with simple ion transfer across a nanopore array was also examined using numerical simulations, via COMSOL Multiphysics software, incorporating a 3-dimensional geometry and employing finite element analysis. Simulated linear sweep voltammograms of TPrA+ transfer demonstrated a unique diffusional behaviour dependent on hexagonal nanopore spacing and the rc/ra ratio, analogous to the experimental voltammograms. Overlay of simulated and experimental voltammograms for each rc/ra ratios showed good agreement. These results indicate that a new design criterion is required to achieve independent diffusion at hexagonal nanointerface arrays, in order to maximize nanodevice performance in electrochemical sensor technologies.

Yousef, Hibba, Liu, Yang, and Zheng, Lianxi (2022) Nanomaterial-based label-free electrochemical aptasensors for the detection of thrombin. Biosensors, 12 (4). 253.
Thrombin plays a central role in hemostasis and its imbalances in coagulation can lead to various pathologies. It is of clinical significance to develop a fast and accurate method for the quantitative detection of thrombin. Electrochemical aptasensors have the capability of combining the specific selectivity from aptamers with the extraordinary sensitivity from electrochemical techniques and thus have attracted considerable attention for the trace-level detection of thrombin. Nanomaterials and nanostructures can further enhance the performance of thrombin aptasensors to achieve high sensitivity, selectivity, and antifouling functions. In highlighting these material merits and their impacts on sensor performance, this paper reviews the most recent advances in label-free electrochemical aptasensors for thrombin detection, with an emphasis on nanomaterials and nanostructures utilized in sensor design and fabrication. The performance, advantages, and limitations of those aptasensors are summarized and compared according to their material structures and compositions.

Welter, Rosilene, Santana, Harrson Silva, Carvalho, Bruna Gregatti, Melani, Natalia, Oelgemoeller, Michael, de la Torre, Lucimara Gaziola, and Taranto, Osvaldir Pereira (2022) Droplet microfluidics for double lipase immobilisation using TiO2 and alginate microbeads. Journal of Industrial and Engineering Chemistry, 110. pp. 576-586.
A double immobilisation technique was developed for C. antarctica lipase (CALB) that improved its enzymatic activity and solved difficulties frequently observed in reactions catalysed by lipases. The first immobilisation consisted of CALB adsorption onto a TiO2 nanoparticle surface (CALB TiO2). The adsorption was carried out by an oriented monolayer formed by CALB’s hydrophilic amino acids and the TiO2 surface, leaving the CALB’s active site accessible for reaction. As a result, an increase in enzymatic activity was achieved. The Relative Enzymatic Activity ((REA) obtained was 289%. The second immobilisation consisted of CALBTiO2 entrapment into calcium alginate microbeads [(CALBTiO2)EDTA-Ca], obtained by an internal crosslinking ion-exchange mechanism and using microfluidic droplet technique. The microbiocatalyst obtained, (CALBTiO2)EDTA-Ca, retained a high enzymatic activity (REAt=0 = 232%) and stability (REAt=30days = 263%) at a size (diameter, Ø=8.9·104 nm) that enabled easier recovery than CALBTiO2 (Ø = 2.3·102 nm) or CALBFree (Ø=5.0 nm), and showed a favourable porosity for diffusion without releasing CALBTiO2. Although the microbeads showed CALBFree leaching, as demonstrated by the loss of REA after a mechanical resistant test, (CALBTiO2)EDTA-Ca maintained an almost constant REA.

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