GSH-doped GQDs using citric acid rich-lime oil extract for highly selective and sensitive determination and discrimination of Fe3+ and Fe2+ in the presence of H2O2 by a fluorescence “turn-off” sensor

Synthesis and characterization of graphene quantum dots (GQDs) simultaneously doped with 1% glutathione (GSH-GQDs) by pyrolysis using citric acid rich-lime oil extract as a starting material. The excitation wavelength (λ_max = 337 nm) of the obtained GSH-GQD solution is blue shifted from that of bare GQDs (λ_max = 345 nm), with the same emission wavelength (λ_max = 430 nm) indicating differences in the desired N and S matrices decorating the carbon based nanoparticles, without any background effect of both ionic strength and masking agent. For highly Fe³⁺-sensitive detection under optimum conditions, acetate buffer at pH 4.0 in the presence of 50 μM H₂O₂, the linearity range was 1.0–150 μM (R² = 0.9984), giving its calibration curve: y = 34.934x + 169.61. The LOD and LOQ were found to be 0.10 and 0.34 μM, respectively. The method’s precisions expressed in terms of RSDs for repeatability (n = 3 × 3 for intra-day analysis) were 2.03 and 3.17% and for reproducibility (n = 5 × 3 for inter-day analysis) were 3.11 and 4.55% for Fe²⁺ and Fe³⁺, respectively. The recoveries of the method expressed as the mean percentage (n = 3) were found in the ranges of 100.1–104.1 and 98.08–102.7% for Fe²⁺ and Fe³⁺, respectively. The proposed method was then implemented satisfactorily for trace determination of iron speciation in drinking water.

Synthesis and characterization of graphene quantum dots (GQDs) simultaneously doped with 1% glutathione (GSH-GQDs) by pyrolysis using citric acid rich-lime oil extract as a starting material.     

Green and facile synthesis of water-soluble carbon dots from ethanolic shallot extract for chromium ion sensing in milk,fruit juices,and wastewater samples

Self-functionalized carbon dots (CDs) were prepared from ethanolic shallot extract to obtain a total phenolic precursor. The total phenolic extract was then heated at 180 °C for four hours in an autoclave. Only 1 mg L⁻¹ of CDs had high fluorescence emission at 430 nm after excitation at 340 nm and manifested a high selectivity for Cr(vi) ions. The inter- and intra-day emission stability, pH, ionic strength, solvent effect, Stern–Volmer constant, incubation time, speciation of Cr(iii) and Cr(vi) ions, and ion selectivity of the as-prepared CDs were investigated in detail. The proposed method was validated in 20–100 μM linearity with y = 2.2346x as the set-zero intercept linear equation, 0.9981 as the correlation coefficient, 3.5 μM as the limit of detection (LOD), 11.7 μM as the limit of quantification (LOQ), and 2.78% and 5.29% as the intra-day and inter-day relative standard deviations (RSD), respectively. The recovery of drinking water, milk, soymilk, fruit juices (apple and coconut), tap water, and chromium-coated industrial waste water by the investigated Cr sensor was found to be 78.58–119.69%. Therefore, the proposed Cr(vi) sensor had superior advantages of sensitivity, selectivity, rapidity, and reproducibility.

Self-functionalized carbon dots (CDs) were prepared from ethanolic shallot extract to obtain a total phenolic precursor.     

Phase I/II study of a candidate vaccine designed against the B and E subtypes of HIV-1

A phase I/II trial of a candidate vaccine to prevent HIV infection was carried out in Bangkok, Thailand, testing AIDSVAX B/E (VaxGen, Inc., Brisbane, CA), a bivalent subunit vaccine prepared by combining recombinant gp120 from a subtype B virus (HIV-1MN) with gp120 from a subtype E virus (HIV-1A244) in alum adjuvant. The studies provide human data on the immunogenicity of various dose combination of non-subtype B vaccine antigens. The results suggest that AIDSVAX B/E is safe and immunogenic in humans. The optimal dose for humans in developing countries was 300 microg of each antigen (B and E). Clade E responses were measurably increased by immunizing with gp120 B/E over B alone. Using the B/E combination did not interfere with the response to either clade. Antibodies to AIDSVAX B/E were able to bind to oligomeric gp120 on the surface of cells infected with primary isolates of HIV-1.     

Adiponectin/ACP30, a collagen-like plasma protein in relation to anthropometric measurement in Thai overweight and obese subjects

Adiponectin, anthropometric parameters including weight, height, body mass index (BMI), arm circumference, triceps skinfold, subscapular skinfold, waist, hip circumferences and waist/hip ratio were recorded in 48 male and 166 female overweight and obese Thai volunteers (BMI?≥?25.0 kg/m²), and in 26 male and 81 female normal subjects (BMI?=?18.5???24.9 kg/m²). Thai volunteers were investigated. Statistically significantly lower adiponectin concentrations in overweight and obese subjects were found when compared with control subjects of both sexes. Anthropometric parameters, including weight, height, BMI, arm circumference, triceps skinfold, subscapular skinfold, waist, hip circumferences and waist/hip ratio, except arm span, were statistically significantly higher in overweight and obese subjects than in control subjects. The overweight and obese subjects had higher glucose concentrations than the control subjects. The BMI and glucose concentrations were found to be significantly related, under these conditions, to adiponectin.     

Selective Fe(ii)-fluorescence sensor with validated two-consecutive working range using N,S,I-GQDs associated with garlic extract as an auxiliary green chelating agent

The goal of this work was to use the pyrolysis process to synthesize graphene quantum dots doped with garlic extract (as N,S-GQDs) and simultaneously co-doped with iodine (as I-GQDs). XPS, HR-TEM, FE-SEM/EDX, FT-IR, fluorescence, and UV-visible absorption spectroscopy were used to characterize the N,S,I-GQDs and analyze their morphological images. The quantum yield of N,S,I-GQDs was found to be 45%, greater than that of undoped GQDs (31%). When stimulated at 363 nm, the N,S,I-GQDs display a strong fluorescence intensity at a maximum wavelength of 454 nm. Using N,S,I-GQDs as a fluorescence quenching sensor for screening tests with various metal ions, it was discovered that they are extremely selective towards Fe²⁺ over Fe³⁺ and other ions. Thus, solution pH, concentration of N,S,I-GQDs, quantity of garlic extract, EDTA and AgNO₃ concentration as masking agents, reaction duration under ultrasonic aid, and tolerable limit of Fe³⁺ presence in the target analyte were all optimized for Fe²⁺ detection. A highly sensitive detection of Fe²⁺ was obtained using a linear curve with y = 141.34x + 5.5855, R² = 0.9961, LOD = 0.11 mg L⁻¹, and LOQ = 0.35 mg L⁻¹. The method precision, given as RSDs, was determined to be satisfactory at 1.04% for intra-day analysis and 3.22% for inter-day analysis, respectively. As a result, the selective determination of trace amounts of Fe²⁺ in real water samples using such labile multi-element doped GQDs in conjunction with garlic extract as a green chelating agent to maintain its enhanced sensitivity was successfully applied with good recoveries ranging from 89.16 to 121.45%.

The goal of this work was to use the pyrolysis process to synthesize graphene quantum dots doped with garlic extract (as N,S-GQDs) and simultaneously co-doped with iodine (as I-GQDs).     

Beyond the bend: a literature review and case report of radial artery loop

Transradial cardiac catheterization is an exciting technique that has many advantages over the traditional femoral approach. Most importantly it is a safe option for PCI with potential same day discharge for uncomplicated cases. Despite its advantages, some challenges may be encountered with the transradial approach. After arterial access and spasm, vascular artery anomalies constitute a significant number of procedural failure. Radial artery anomalies are encountered in greater than 17% of cases performed in literature. In particular, radial loop is an important cause of transradial procedural failure. We present a literature review and a case from our institution and outline techniques in order to traverse the loop and make the transradial approach a success.     

The use of S2O82− and H2O2 as novel specific masking agents for highly selective “turn-on” fluorescent switching recognition of CN− and I− based on Hg2+–graphene quantum dots

In this study, we report that both CN⁻ and I⁻ can enhance the fluorescent intensity of Hg²⁺–graphene quantum dots (Hg²⁺–GQDs). However, the selectivity of the sensor was poor. Accordingly, simple specific masking agents can be directly used to solve this problem. Here, for the first time, we report the use of persulfate ion (S₂O₈²⁻) as a turn-on fluorescent probe of Hg²⁺–GQDs for selective CN⁻ detection, while hydrogen peroxide (H₂O₂) was selected for its sensing ability towards I⁻ ion detection. Interestingly, the signal was immediately measured after addition of the masking agent to Hg²⁺–GQDs and the sample because its interaction was very fast and efficient. The method had a linear response in the concentration ranges of 0.5–8 μM (R² = 0.9994) and 1–12 μM (R² = 0.9998) with detection limits of 0.17 and 0.20 μM for CN⁻ and I⁻, respectively. The sensor was successfully used for the dual detection of both CN⁻ and I⁻ in real water samples with satisfactory results. In conclusion, the specific masking agents in a Hg²⁺–GQDs system appeared to be good candidates for fluorometric “turn-on” sensors for CN⁻ and I⁻ with excellent selectivity over other ions.

In this study, we report that both CN⁻ and I⁻ can enhance the fluorescent intensity of Hg²⁺–graphene quantum dots (Hg²⁺–GQDs).     

From the Cover: Sex-specific ornament evolution is a consistent feature of climatic adaptation across space and time in dragonflies

Adaptation to different climates fuels the origins and maintenance of biodiversity. Detailing how organisms optimize fitness for their local climates is therefore an essential goal in biology. Although we increasingly understand how survival-related traits evolve as organisms adapt to climatic conditions, it is unclear whether organisms also optimize traits that coordinate mating between the sexes. Here, we show that dragonflies consistently adapt to warmer climates across space and time by evolving less male melanin ornamentation—a mating-related trait that also absorbs solar radiation and heats individuals above ambient temperatures. Continent-wide macroevolutionary analyses reveal that species inhabiting warmer climates evolve less male ornamentation. Community-science observations across 10 species indicate that populations adapt to warmer parts of species’ ranges through microevolution of smaller male ornaments. Observations from 2005 to 2019 detail that contemporary selective pressures oppose male ornaments in warmer years; and our climate-warming projections predict further decreases by 2070. Conversely, our analyses show that female ornamentation responds idiosyncratically to temperature across space and time, indicating the sexes evolve in different ways to meet the demands of the local climate. Overall, these macro- and microevolutionary findings demonstrate that organisms predictably optimize their mating-related traits for the climate just as they do their survival-related traits.

Dating back to Darwin (1) and Wallace (2), biologists have long hypothesized that much of the Earth’s biodiversity was forged by adaptation to different climates. Characterizing how organisms respond to climatic factors, like temperature, is therefore an enduring goal in biology, which has become even more crucial due to the ongoing climate crisis (3). To date, researchers have uncovered many ways that organisms improve survival in their local climates through the evolution of traits such as physiological tolerance (4), life cycle timing (5), and body size (6). However, recent work reveals that climatic adaptation can also involve optimizing mating and reproduction in addition to survival (7). The evolution of sexual traits that coordinate mating could therefore be an important way that plants and animals improve fitness in their local climate from one generation to the next. Nevertheless, despite >95% of eukaryotic taxa engaging in sexual reproduction, it is unclear if sexual characters are a dimension of the phenotype that organisms typically optimize for the climate (3, 8–10).One type of sexual trait that could often be involved in climatic adaptation is ornamental coloration, which many animals use to attract mates and intimidate rivals. As the dark and/or saturated colors used in many ornaments absorb solar radiation and lead to heating, the demands of warmer climates could force animals to evolve smaller or less saturated ornaments (9, 11, 12). Alternatively, because tropical species are frequently more ornately colored than their temperate relatives, some researchers have suggested that adaptation to warmer climates may instead favor more exaggerated ornamentation (13). By understanding how ornamental coloration responds to selective pressures in different climates, we can begin to resolve if the evolution of sexual traits is indeed a major feature of how organisms adapt to the climate (3, 10).Testing if ornaments respond predictably to climatic factors across multiple lineages and/or timescales is one approach to assessing ornament evolution’s role in climatic adaptation (14, 15). If, for example, selective pressures in warmer climates require the evolution of less exaggerated ornamentation, then we should observe that animals inhabiting hotter environments consistently evolve less ornamental color regardless of timescale or historical contingencies (e.g., differing genetic backgrounds, or genetic drift) (14). Dragonflies and damselflies are well suited for such tests because they possess ornamental wing melanization that varies within and among species (16). Males with greater wing melanization typically attract more mates and ward off territorial rivals, and both sexes use these ornaments to signal their species’ identity to con- and heterospecifics (16). Though these advantages in courtship and rival intimidation often favor greater ornamentation, wing melanization can also heat individuals >2 °C (11, 12, 17). Such heating may provide modest locomotor benefits under cool conditions (11), but it can damage wing tissue, reduce male fighting ability and territorial defense, and even cause death under warm conditions (11, 17). In contrast, because females mainly spend their time foraging in cooler and/or more shaded microhabitats to maximize fecundity (16), their wing melanization may rarely cause overheating. These sex-specific thermal consequences for both reproduction and survival suggest that dragonflies should adapt to their local climates across space and time through the evolution of ornamental wing melanization in males but not necessarily in females (11, 12). We tested this hypothesis by exploring how male and female ornaments have responded to climatic differences across the macroevolutionary, microevolutionary, and contemporary history of Nearctic dragonflies.To first evaluate if selective pressures in different climates have favored ornament evolution across macroevolutionary timescales, we tested if Nearctic dragonfly species inhabiting warmer ranges are less likely to have evolved wing melanization than those inhabiting cooler ranges. Using field guides, community-science observations, and >387,900 occurrence records from the Global Biodiversity Information Facility (https://www.gbif.org), we compiled phenotypic and climatic data for 319 Nearctic species (Fig. 1 A and B). After controlling for shared evolutionary history, we found sex-specific patterns of ornament evolution among climates. Species with warmer ranges are indeed less likely to have male wing melanization than species with cooler ranges (β ± SE = −0.078 ± 0.024, 95% CIs = −0.162 to −0.035; Fig. 1C). Species with the darkest patches of male wing melanization also tend to have the coolest ranges (β ± SE = −0.010 ± 0.004, 95% CIs = −0.017 to −0.003). However, interspecific patterns for female wing melanization contrasted starkly with these patterns for males. Species with warmer ranges have a somewhat higher probability of female wing melanization, though the trend is not different from zero (β ± SE = 0.027 ± 0.016, 95% CIs = −0.008 to 0.068; Fig. 1D). There is also no relationship between the temperature of a species’ range and the darkness of its female wing melanization (β ± SE = −0.006 ± 0.004, 95% CIs = −0.012 to 0.001). Thus, the evolution of male, but not female, wing melanization is a component of how dragonflies respond to climatic differences over long timescales.Open in a separate windowFig. 1.Macroevolution of dragonfly wing melanization in relation to temperature. (A) Nearctic dragonfly phylogeny. Filled tips indicate the presence of male (green) and female (purple) wing melanization. (B) Dragonfly species across the Nearctic. (C and D) Probability of males (C) and females (D) possessing wing melanization. Tick marks are species (n = 319), and lines are from phylogenetic logistic regressions.These macroevolutionary findings indicate that selective pressures in warmer climates have favored less male, but not female, ornamentation among Nearctic dragonfly species. However, most dragonfly species are much older than their current geographic distributions (16). Thus, as is true in many studies of ancient lineages, these biogeographic patterns probably stem from both ecological filtering and adaptation. For instance, following the Last Glacial Maximum, species may have recolonized regions where the climatic conditions did not make male ornamentation too costly (i.e., ecological filtering) (12). Additionally, because ornamentation is quite evolutionarily labile (18), these macroevolutionary patterns likely also arise from adaptation to local climates. The relative contributions of colonization and adaptation to interspecific ornament variation cannot yet be disentangled for this group or for many other ancient clades. Nevertheless, if adaptation to local climatic conditions has led species to evolve differing ornamentation over long timescales, then it should also entail ornament evolution across shorter timescales—such as those separating populations within the same species.To evaluate if populations consistently adapt to their local climates via ornament evolution, we next tested for parallel shifts in ornament size across the ranges of 10 widely distributed Nearctic dragonfly species (14) (Fig. 2). Here, we measured the proportion of melanized wing area on >2,700 dragonfly observations from the community-science platform iNaturalist (https://www.inaturalist.org) (19). Despite some of these species being separated by >100 My of evolution, we found that their constituent populations exhibit remarkably parallel responses in their male, but not female, ornamentation. Within 7 of the 10 species, males in warmer regions had significantly less wing melanization than their counterparts in cooler areas (Fig. 2A and SI Appendix, Table S1). Consequently, when averaging across all 10 species’ responses, male wing melanization tended to decrease as local temperatures increased (β ± SE = −0.064 ± 0.031 SD per 1 °C; 95% CIs = −0.127 to −0.001). Because developing at warmer temperatures does not induce male dragonflies to express less ornamentation (20), genetic differences among populations are more likely to underlie these parallel responses than phenotypic plasticity alone. In contrast to the patterns in males, females possessed significantly less wing melanization in warmer climates for only 3 out of 10 species (Fig. 2A and SI Appendix, Table S1). As a result, the average female response to temperature across the 10 species was indistinguishable from 0 (β ± SE = −0.006 ± 0.024 SD per 1 °C; 95% CIs = −0.054 to 0.042). Thus, mirroring macroevolutionary patterns among species, the differing selective pressures among climates also favor consistent patterns of sex-specific ornament evolution within species (Fig. 2B). In particular, these sex-specific responses within species result in male ornaments being 25.8 ± 2.0% larger than female ornaments in the coolest parts of North America, on average, but only 2.0 ± 3.3% larger in the warmest areas.Open in a separate windowFig. 2.Parallel evolution of wing melanization in response to mean annual temperature (MAT) within dragonfly species. (A) Graphs show species’ relationships for males (green) and females (purple). Points are individuals (n = 2,718), and lines are fitted from linear mixed-effects models. Asterisks indicate significant declines. (B) Average within-species SD change wing melanization (± SE) for 1 °C increase.Across timescales ranging from >150 My to only dozens of millennia, our results show that dragonflies consistently adapt to their climate via sex-specific evolution of wing melanization. However, climatic projections indicate North America could warm >4.5 °C by 2070 (21). The ornament evolution that previously facilitated adaptation over thousands of years may therefore need to occur over fewer than 100 generations unless alternative responses can be employed. Two such alternatives to rapid ornament evolution are shifts in species’ distributions and phenologies (22). For instance, more-ornamented species could lessen the threat of overheating by tracking northward shifts of cooler temperatures. When we incorporated each species’ ornamentation into a recently published analysis of range shifts among 65 European dragonflies (23), however, we found that species with male ornamentation have not moved further northward than species without it (difference in northward range shifts ± SE = 10.50 ± 24.33 km, 95% CIs = −37.19 to 58.18). More-ornamented species could also alleviate the risk of overheating by shifting phenology to defend territories in cooler times of day or to reproduce in cooler times of year (22). Though we cannot rule out this possibility, it is notable that such phenological shifts, if they occur, have not enabled males to possess greater ornamentation in warmer climates over the previous >150 My. Rapid ornament evolution may therefore be necessary to avoid overheating as our planet’s climate changes (24).To evaluate how natural and sexual selection might alter ornamentation as the Earth warms, we tested if the 10 widely distributed dragonfly species (Fig. 2) possessed less wing melanization in years that were warmer than the Northern Hemisphere’s long-term average (mean temperature anomaly). Our analyses show that, from 2005 to 2019, species averaged less wing melanization in warmer years for males but not females (males: β ± SE = −0.263 ± 0.103 SD per 1 °C, 95% CIs = −0.513 to −0.005; females: β ± SE = −0.118 ± 0.146 SD per 1 °C, 95% CIs = −0.418 to 0.181; Fig. 3). However, since males and females responded more similarly to each other across annual variation than geographic variation, the estimated extent of sexual dimorphism was only modestly more male biased in cold years (16.0 ± 1.5%) than in warm years (14.5 ± 1.9%). Nonetheless, these results collectively reveal that male ornaments were smallest in this century’s warmest years. By contrast, our analyses show that the extent of wing melanization did not exhibit a net decrease across the 15-y timespan for either sex nor was it related to the previous year’s temperature (SI Appendix, Table S8). The temporal patterns in ornament size therefore likely emerge from processes operating within generations rather than across generations. As dragonflies do not develop less wing melanization when reared under warmer conditions (20), a probable explanation for this within-generation effect is that selection in warmer years consistently reduces the number of highly ornamented individuals in breeding populations.Open in a separate windowFig. 3.Wing melanization shifts with interannual temperature variation. (A) Lines show fitted relationship (with 95% CIs) between wing melanization (SD relative to mean) and the Northern Hemisphere’s yearly temperature anomaly from 2005 to 2019 (n = 2,620). (B) Estimated-marginal mean wing melanization (with 95% CIs) for 2005 to 2019. The sexes’ points are offset horizontally to reduce overlap.Since selective pressures in warmer years appear to favor less ornamented males, we estimated how wing melanization might shift as North America warms over the next several decades. Based on the best- and worst-case scenarios for climatic warming (21), we used the current geographic relationship between ornamentation and temperature to forecast the amount of wing melanization each species should possess in 2070 for the coolest third, thermal midpoint, and warmest third of its range (21, 24) (SI Appendix, Table S3). Our projections indicate that, on average, species’ male wing melanization will decline 0.205 to 0.328 SD by 2070 (SI Appendix, Table S3)—a modest loss of only up to 0.007 SD per generation. In contrast, species’ female wing melanization will not need to change significantly (SI Appendix, Table S3). The breeder’s equation can illuminate the plausibility of dragonflies losing this much male wing melanization each generation to match yearly warming of 0.09 °C (4.5 °C/50 y) (24). Assuming that phenotypic selection underlies the interannual ornament variation we observed (Fig. 3B), selection in each generation will favor, on average, 0.024 SD less male wing melanization than it did in the previous generation (−0.263 SD ornamentation °C⁻¹ × 0.09 °C Y⁻¹). For male ornamentation to keep pace with this intensity of selection each generation, heritability would need to average 0.277 ± 0.111. This h² is similar to the estimated mean for all adult traits in animals [h² = 0.247 ± 0.032 (25)] and smaller than the estimated mean for melanin-based traits in insects (h² = 0.463 ± 0.114; see SI Appendix). Because the capacity for rapid responses to climatic warming is often limited along other phenotypic axes [e.g., physiological tolerance (4, 26, 27)], the modest projected responses and moderate requisite heritability of male wing melanization suggest that ornament evolution could be an important component of climatic adaptation in the coming years.Table 1.Average forecasted shifts (± SE), and 95% prediction intervals, that will be necessary for dragonflies to optimize their wing melanization to the climatic conditions of 2070 across North America

Adiponectin/ACP30, a collagen-like plasma protein in relation to anthropometric measurement in Thai overweight and obese subjects

Adiponectin, anthropometric parameters including weight, height, body mass index (BMI), arm circumference, triceps skinfold, subscapular skinfold, waist, hip circumferences and waist/hip ratio were recorded in 48 male and 166 female overweight and obese Thai volunteers (BMI=25.0 kg/m(2)), and in 26 male and 81 female normal subjects (BMI=18.5-24.9 kg/m(2)). Thai volunteers were investigated. Statistically significantly lower adiponectin concentrations in overweight and obese subjects were found when compared with control subjects of both sexes. Anthropometric parameters, including weight, height, BMI, arm circumference, triceps skinfold, subscapular skinfold, waist, hip circumferences and waist/hip ratio, except arm span, were statistically significantly higher in overweight and obese subjects than in control subjects. The overweight and obese subjects had higher glucose concentrations than the control subjects. The BMI and glucose concentrations were found to be significantly related, under these conditions, to adiponectin.