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Solving mathematical equations faster and more efficiently has been a Holy Grail for centuries for scientists and engineers across all disciplines. While electronic digital circuits have revolutionized equation solving in recent decades, it has become apparent that performance gains from brute-force approaches of compute-solvers are quickly saturating over time. Instead, paradigms that leverage the universes’ natural tendency to minimize a system’s free energy, such as annealers or Ising Machines, are being sought after due to favorable complexity scaling. Here, we introduce a programmable analog solver leveraging the formal mathematical equivalence between Maxwell’s equations and photonic circuitry. It features a mesh network of nanophotonic beams to find solutions to partial differential equations. As an example, we designed, fabricated, and demonstrated a novel application-specific photonic integrated circuit comprised of electro-optically reconfigurable nodes and experimentally validated 90 % accuracy with respect to a commercial solver. Finally, we tested this photonic integrated chip performance by simulating thermal diffusion on a spacecraft’s heat shield during re-entry to a planet’s atmosphere. The programmable light-circuitry presented herein offers a facile route for solving complex problems and thus will have profound potential applications across many scientific and engineering fields.

The development of superhydrophobic materials with inexpensive cost, and simple preparation processes is crucial for alleviating oil pollution. In this paper, cotton-based composites (cotton@LDH-SA) were prepared by an in situ hydrothermal growth and simple impregnation method. The needle-like Ni–Co LDHs growing on the surface of the cotton fibers formed micro/nano hierarchical structures, and subsequently grafted stearic acid endowing the composite with superwettability. The optimized cotton@LDH-SA possesses a superior superhydrophobicity with a water contact angle of 161.6 ± 2°. The prepared composite adsorbent exhibits excellent oil absorption performance with an adsorption capacity of more than 10 times its own mass. The adsorbent has acceptable reusability, and after 6 cycles of repeated adsorption, the adsorption rate remains at 72.4%. Given the excellent economic and renewable properties of cotton, this composite adsorbent has great potential for application in large-scale production and oil–water separation. [ABSTRACT FROM AUTHOR]

Here, a simple spraying-induced in situ growth of inorganic particles strategy was adopted to fabricate composite membranes. Sodium alginate was first sprayed on a polyvinylidene fluoride membrane to provide active sites, and subsequently, alternate spraying of Ca2+ and CO32− induced in situ growth of CaCO3 particles to construct hierarchical structures. The optimal membrane exhibited superhydrophilicity/underwater superoleophobicity. The membrane has good oil–water separation efficiency (>99%) and high flux (>2238 L m−2 h−1) for several oil–water emulsions. Importantly, the membrane retained acceptable separation performance even after 10 cycles, proving its good mechanical stability and anti-fouling features. The current work may open up a new avenue for the large-scale fabrication of super-wetting membranes for oily wastewater remediation. [ABSTRACT FROM AUTHOR]

Diboride‐based ultra‐high temperature ceramics (UHTCs) are a special class of ceramics with excellent comprehensive properties, which have extensive potential applications in extreme environments. However, their practical applications are limited, mainly due to the poor fracture toughness and thermal shock resistance. Refractory metals have high melting points, good ductility, and high toughness, which have huge potential to improve the properties of diboride‐based ceramics. As a special class of additives, they have been adopted to promote densification, improve microstructure, and properties. However, diboride‐based ceramics containing refractory metals have not received adequate attention due to relatively weak practical effects on property improvement. The present review highlights the progress and existing problems of transition metal diborides with refractory metal additives, including W, Ta, Mo, Nb, Hf, V, Cr, and Zr, focusing mainly on the microstructure change and property improvements, followed by challenges and possible future development strategies. [ABSTRACT FROM AUTHOR]

The super line graph of index r, denoted by L r (G) , is defined for any graph G with at least r edges. Its vertices are the sets of r edges of G, and two such sets are adjacent if an edge of one is adjacent to an edge of the other. In this paper, we give an explicit characterization for all graphs G with L 2 (G) being a complete graph. We present lower bounds for the clique number and chromatic number of L 2 (G) for several classes of graphs. In addition, bounds for the domination number of L 2 (G) are established in terms of the domination number of the line graph L (G) of a graph. A number of related problems on L 2 (G) are proposed for a further study. [ABSTRACT FROM AUTHOR]

Electron transport layers (ETLs) with excellent electron extraction capability are essential for realizing high efficiency in organic solar cells (OSCs). A sol–gel-processed ZnO ETL is widely used in OSCs due to its high mobility and suitable work function. However, the existence of defects usually results in low photovoltaic performance during the operation of OSCs. In this work, glucose (Gl) was used to passivate free OH traps via hydrogen-bonding interaction and formed ZnO/Gl ETLs with ZnO, which exhibited improved electron extraction capability and reduced trap defect density. Thus, a champion efficiency of 18.03% was obtained in a PM6:Y6 light absorber-based cell, which is >11% higher than that of the reference cell (16.15%) with a pristine ZnO ETL. Impressive enhancements by >11% were also observed in different fullerene and non-fullerene light absorber-based cells relative to that of the reference cell. This study demonstrates a new strategy to design ETLs for realizing high efficiency in OSCs. [ABSTRACT FROM AUTHOR]

In the past decade, there is an increasing interest in the deployment of unmanned surface vehicles (USVs) for undertaking ocean missions in dynamic, complex maritime environments. The success of these missions largely relies on motion planning algorithms that can generate optimal navigational trajectories to guide a USV. Apart from minimising the distance of a path, when deployed a USVs’ motion planning algorithms also need to consider other constraints such as energy consumption, the affected of ocean currents as well as the fast collision avoidance capability. In this paper, we propose a new algorithm named anisotropic GPMP2 to revolutionise motion planning for USVs based upon the fundamentals of GP (Gaussian process) motion planning (GPMP, or its updated version GPMP2). Firstly, we integrated the anisotropy into GPMP2 to make the generated trajectories follow ocean currents where necessary to reduce energy consumption on resisting ocean currents. Secondly, to further improve the computational speed and trajectory quality, a dynamic fast GP interpolation is integrated in the algorithm. Finally, the new algorithm has been validated on a WAM-V 20 USV in a ROS environment to show the practicability of anisotropic GPMP2. Note to Practitioners—The work reported in this article will be significant for USVs to conduct missions in complex, dynamic maritime environments where various obstacles and time-varying ocean currents exit. We develop this novel motion planning algorithm based on Gaussian process and optimise the trajectory using probabilistic inferences. The new algorithm can generate collision free trajectories that also minimise the influences caused by adverse ocean currents in a highly efficient way. In addition, the planning has been undertaken in a continuous-time domain making the generated trajectory have a guaranteed smoothness and readily feasible for autopilots to track. We use a coastal area with time-varying vortexes to present a challenging practical maritime environment. The presented algorithm integrates the available information about a fluid field regarding energy consumption and hazard level, along with the density of obstacles to plan a navigational route efficiently. To increase the practical performance of the proposed method, diverse models for generating ocean currents need to be developed in the future to tackle unpredictable situations. [ABSTRACT FROM AUTHOR]

Human milk oligosaccharides (HMOs) have recently attracted ever-increasing interest because of their versatile physiological functions. In HMOs, two tetrasaccharides, lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT), constitute the essential components, each accounting 6% (w/w) of total HMOs. Also, they serve as core structures for fucosylation and sialylation, generating functional derivatives and elongation generating longer chains of core structures. LNT, LNnT, and their fucosylated and/or sialylated derivatives account for more than 30% (w/w) of total HMOs. For derivatization, LNT and LNnT can be modified into a series of complex fucosylated and/or sialylated HMOs by transferring fucose residues at α1,2-, α1,3-, and α1,3/4-linkage and/or sialic acid residues at α2,3- and α2,6-linkage. Such structural diversity allows these HMOs to possess great commercial value and an application potential in the food and pharmaceutical industries. In this review, we first elaborate the physiological functions of these tetrasaccharides and derivatives. Next, we extensively review recent developments in the biosynthesis of LNT, LNnT, and their derivatives in vitro and in vivo by employing advanced enzymatic reaction systems and metabolic engineering strategies. Finally, future perspectives in the synthesis of these HMOs using enzymatic and metabolic engineering approaches are presented. [ABSTRACT FROM AUTHOR]

Apples are one of the most widely planted fruits in the world, with an extremely high annual production. Several issues should be addressed to avoid the damaging of samples during the quality grading process of apples (e.g., the long detection period and the inability to detect the internal quality of apples). In this study, an electronic nose (e-nose) detection system for apple quality grading based on the K-nearest neighbor support vector machine (KNN-SVM) was designed, and the nasal cavity structure of the e-nose was optimized by computational fluid dynamics (CFD) simulation. A KNN-SVM classifier was also proposed to overcome the shortcomings of the traditional SVMs. The performance of the developed device was experimentally verified in the following steps. The apples were divided into three groups according to their external and internal quality. The e-nose data were pre-processed before features extraction, and then Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used to reduce the dimension of the datasets. The recognition accuracy of the PCA–KNN-SVM classifier was 96.45%, and the LDA–KNN-SVM classifier achieved 97.78%. Compared with other commonly used classifiers, (traditional KNN, SVM, Decision Tree, and Random Forest), KNN-SVM is more efficient in terms of training time and accuracy of classification. Generally, the apple grading system can be used to evaluate the quality of apples during storage. [ABSTRACT FROM AUTHOR]

In this paper, we will use MATLAB to create a Markov model, determine the input and output membership functions of the study area, and import the data of the study area into the model. The ROC method is used to prove the accuracy of the sensitivity distribution map of mountain landslide disaster and the feasibility of the model in the sensitivity assessment of mountain landslide. It also shows the reliability and applicability of the selected factors. Based on GIS technology, the influencing factors of sensitivity coefficient of landslides in mountainous areas can be extracted. According to the spatial distribution characteristics of landslides, six influencing factors of landslides and their spatial distribution relationships are analyzed: height, slope, geological lithology, terrain curvature, terrain humidity index, and runoff intensity index. Training management combined with aerobic exercise is helpful to improve people's body shape. The effect of "resistance training + aerobic exercise" training method adopted by experimental group 1 on body shape is the most significant. The arm circumference of the male experimental group increased, while that of the female experimental group decreased. In the training management, different combination methods of resistance training and aerobic exercise have no significant effect on the improvement of the muscle strength of the subjects after the experiment. By analyzing and comparing the changes of cardiopulmonary function indexes of the subjects before and after training, this paper expounds the training effect of blood flow restriction under different pressures combined with low-intensity aerobic exercise on cardiopulmonary function. In this paper, through the study of the Markov model and mountain landslide sensitivity, it is applied to aerobic training management, which promotes the better improvement of people's body shape. [ABSTRACT FROM AUTHOR]

In this work, a novel magnetic nanomaterial functionalized with a molecularly imprinted polymer was prepared for the extraction of protoberberine alkaloids. Molecularly imprinted polymers were made on the surface of Fe3O4 nanoparticles by using berberine as template, acetonitrile/water as porogen, acrylamide as functional monomer and ethylene glycol dimethacrylate as cross-linker. The optimized molar ratio of template/functional monomer was 1:7. The polymeric magnetic nanoparticles were characterized by transmission electron microscopy and Fourier transform infrared spectroscopy. The stability and adsorption capacity of the molecularly imprinted polymers were investigated. The molecularly imprinted polymers were used as a selective sorbent for the magnetic molecularly imprinted solid-phase extraction and determination of jatrorrhizine, palmatine, and berberine. Extraction parameters were studied including loading pH, sample volume, stirring speed, and extraction time. Finally, a magnetic molecularly imprinted solid-phase extraction coupled to high-performance liquid chromatography method was developed. Under the optimized conditions, the method showed good linear range of 0.1-150 ng/mL for berberine and 0.1-100 ng/mL for jatrorrhizine and palmatine. The limit of detection was 0.01 ng/mL for berberine and 0.02 ng/mL for jatrorrhizine and palmatine. The proposed method has been applied to determine protoberberine alkaloids in Cortex phellodendri and rat plasma samples. The recoveries ranged from 87.33-102.43%, with relative standard deviation less than 4.54% in Cortex phellodendri and from 102.22-111.15% with relative standard deviation less than 4.59% in plasma. [ABSTRACT FROM AUTHOR]

Abstract Human milk oligosaccharides (HMOs) have attracted considerable attention owing to their unique physiological functions. Two important tetrasaccharides, lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT), are core structures of HMOs. Their safety has been evaluated and they can be added to infant formula as functional ingredients. The fucosylated derivatives of LNT and LNnT, mainly lacto-N-fucopentaose (LNFP) I, LNFP II, LNFP III, and lacto-N-difucohexaose I, exhibit prominent physiological characteristics, including modificating the intestinal microbiota, immunomodulation, anti-bacterial activities, and antiviral infection. However, they have received lesser attention than 2’-fucosyllactose. As precursors, LNT and LNnT are connected to one or two fucosyl units through α1,2/3/4 glycosidic bonds, forming a series of compounds with complex structures. These complex fucosylated oligosaccharides can be biologically synthesized using enzymatic and cell factory approaches. This review summarizes the occurrence, physiological effects, and biosynthesis of fucosylated LNT and LNnT derivatives and their future development. [ABSTRACT FROM AUTHOR]

Poultry breeding is one of the most significant components of agriculture and an essential link of material exchange between humans and nature. Moreover, poultry breeding technology has a considerable impact on the life quality of human beings, and could even influence the survival of human beings. As one of the most popular poultry, broiler has a good economic benefit due to its excellent taste and fast growing cycle. This paper aims to improve the efficiency of raising broilers by understanding the impact of ammonia concentration distribution within a smart broiler breeding chamber, and the rationality of the system's design. More specifically, we used computational fluid dynamics (CFD) technology to simulate the process of ammonia production and identify the characteristics of ammonia concentration. Based on the simulation results, the structure of the broiler chamber was reformed, and the ammonia uniformity was significantly improved after the structural modification of the broiler chamber and the ammonia concentration in the chamber had remained extremely low. In general, this study provides a reference for structural optimization of the design of broiler chambers and the environmental regulation of ammonia. [ABSTRACT FROM AUTHOR]

The first total synthesis of the thiazole-containing cyclic depsipeptide pagoamide A, is detailed. The longest linear sequence of the liquid-phase synthesis comprises 9 long linear steps from simple known starting materials, which led to the unambiguous structural confirmation of pagoamide A. [ABSTRACT FROM AUTHOR]

Lacto- N -triose II (LNTri II), an important precursor for human milk oligosaccharide (HMOs) synthesis, has garnered significant attention due to its structural features and physiological properties. Composed of galactose (Gal), N -acetylglucosamine (GlcNAc), and glucose (Glc), with the chemical structure GlcNAcβ1,3Galβ1,4Glc, the distinctive structure of LNTri II confers various physiological functions such as promoting the growth of beneficial bacteria, regulating the infant immune system, and preventing certain gastrointestinal diseases. Extensive research efforts have been dedicated to elucidating efficient enzymatic synthesis pathways for LNTri II production, with particular emphasis on the transglycosylation activity of β- N -acetylhexosaminidases and the action of β-1,3- N -acetylglucosaminyltransferases. Additionally, metabolic engineering and cell factory approaches have been explored, harnessing the potential of engineered microbial hosts for the large-scale biosynthesis of LNTri II. This review summarizes the structure, derivatives, physiological effects, and biosynthesis of LNTri II.

Human milk oligosaccharides (HMOs) have attracted considerable attention owing to their unique physiological functions. Two important tetrasaccharides, lacto- N -tetraose (LNT) and lacto- N -neotetraose (LNnT), are core structures of HMOs. Their safety has been evaluated and they can be added to infant formula as functional ingredients. The fucosylated derivatives of LNT and LNnT, mainly lacto- N -fucopentaose (LNFP) I, LNFP II, LNFP III, and lacto- N -difucohexaose I, exhibit prominent physiological characteristics, including modificating the intestinal microbiota, immunomodulation, anti-bacterial activities, and antiviral infection. However, they have received lesser attention than 2'-fucosyllactose. As precursors, LNT and LNnT are connected to one or two fucosyl units through α1,2/3/4 glycosidic bonds, forming a series of compounds with complex structures. These complex fucosylated oligosaccharides can be biologically synthesized using enzymatic and cell factory approaches. This review summarizes the occurrence, physiological effects, and biosynthesis of fucosylated LNT and LNnT derivatives and their future development.

Background: It is unclear whether 25(OH)D concentrations in children and female adults may be influenced by inflammation and thus require adjustment when estimating the population prevalence of vitamin D deficiency., Objectives: We examined correlations between inflammation biomarkers, CRP or alpha-1-acid glycoprotein (AGP), and serum 25(OH)D concentrations among preschool children (PSC; 6-59 mo) and nonpregnant females of reproductive age (FRA; 15-49 y)., Methods: We analyzed cross-sectional data from 6 nationally representative nutrition surveys (Afghanistan, Cambodia, Pakistan, UK, USA, and Vietnam) conducted among PSC (n = 9880) and FRA (n = 14,749) from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia project. Rank correlations between CRP or AGP and 25(OH)D concentrations were examined while taking into account complex survey design effects., Results: Among both PSC and FRA, correlations between inflammation and vitamin D biomarkers were weak and inconsistent across surveys. For PSC, correlation coefficients between CRP and 25(OH)D concentrations ranged from -0.04 to 0.08, and correlations between AGP and 25(OH)D ranged from 0.01 to 0.05. Correlation coefficients between CRP and 25(OH)D for FRA ranged from -0.11 to 0.14, and correlations between AGP and 25(OH)D concentrations ranged from -0.05 to 0.01., Conclusions: Based on the weak and inconsistent correlations between CRP or AGP and 25(OH)D, there is no rationale to adjust for these inflammation biomarkers when estimating population prevalence of vitamin D deficiency in PSC or FRA., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Over the last decade, there has been an increased interest in developing aerial robotic platforms that exhibit grasping and perching capabilities not only within the research community but also in companies across different industry sectors. Aerial robots range from standard multicopter vehicles/drones, to autonomous helicopters, and fixed-wing or hybrid devices. Such devices rely on a range of different solutions for achieving grasping and perching. These solutions can be classified as: 1) simple gripper systems, 2) arm-gripper systems, 3) tethered gripping mechanisms, 4) reconfigurable robot frames, 5) adhesion solutions, and 6) embedment solutions. Grasping and perching are two crucial capabilities that allow aerial robots to interact with the environment and execute a plethora of complex tasks, facilitating new applications that range from autonomous package delivery and search and rescue to autonomous inspection of dangerous or remote environments. In this review paper, we present the state-of-the-art in aerial grasping and perching mechanisms and we provide a comprehensive comparison of their characteristics. Furthermore, we analyze these mechanisms by comparing the advantages and disadvantages of the proposed technologies and we summarize the significant achievements in these two research topics. Finally, we conclude the review by suggesting a series of potential future research directions that we believe that are promising., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Meng, Buzzatto, Liu and Liarokapis.)

Human milk oligosaccharides (HMOs) attract particular attention because of their health benefits for infants. Lacto- N -neotetraose (LNnT) is one of the most abundant neutral core structures of HMOs. Bacterial β-1,4-galactosyltransferase (β-1,4-GalT) displays an irreplaceable role in the practical application of LNnT biosynthesis. In this study, a novel β-1,4-GalT from Histophilus somni was identified to efficiently synthesize LNnT from UDP-Gal and lacto- N -triose II (LNT II). The optimum pH and temperature were determined to be pH 6.0 and 30 °C, respectively. The enzyme showed both transgalactosylation and hydrolysis activity, with a specific activity of 3.7 and 6.6 U/mg, respectively. LNnT was synthesized using H. somni β-1,4-GalT via both enzymatic and cell factory approaches, and both approaches provided an LNnT ratio with the remaining LNT II at approximately 1:2 when reactions attained a balance. These findings indicated that H. somni β-1,4-GalT has a potential in biosynthesis of LNnT and derivatives in future.

Purpose: To evaluate the sensitivity of apoptosis-stimulating protein of p53 (ASPP) and P-glycoprotein (P-gp) to the recombinant human adenovirus-p53 (rAd-p53) combined with neoadjuvant chemotherapy for locally advanced cervical cancer and their predictive value for efficacy., Methods: 80 patients with histopathologically diagnosed locally advanced cervical cancer (stage Ib2-IIa2) and operative treatment from February 2009 to June 2013 were enrolled and randomly divided into 3 groups: radical hysterectomy group (RH group, n=30), simple intravenous chemotherapy with cisplatin paclitaxel group (TP group, n=30) and gene therapy + intravenous chemotherapy group with cisplatin+paclitaxel (rAd-p53 + TP group, n=20). Patients in the RH group were directly operated, those in the TP group were treated with TP chemotherapy for 2 courses, and those in the rAd-p53 + TP group were treated with the same chemotherapy regimen and the rAd-p53 agent (1×1012 virus particles) was injected for the first time 3 days after chemotherapy for 3 times. The changes in tumor volume, adverse reactions and survival of patients in the TP group and rAd-p53 + TP group, and the levels of p53, ASPP2, inhibitory member of the ASPP family (iASPP) and P-gp in postoperative tumor tissues in the 3 groups were evaluated., Results: The efficacy was evaluated for all patients in the TP group and rAd-p53 + TP group 3 weeks after chemotherapy. The tumor was reduced by 10.90±2.62 cm2 after medication in the TP group and 15.25±4.01 cm2 after medication in rAd-p53 + TP group, and the difference was statistically significant. The response rate [complete response (CR) + partial response (PR)] was 76.7% in the TP group and 95% in the rAd-p53 + TP group, with statistically significant difference. The positive expression rate of p53 protein showed a gradual decreasing trend in the RH group, TP group and rAd-p53 + TP group, with statistically significant difference (p<0.05). The positive expression rate of ASPP2 displayed a gradual increasing trend in the RH group, TP group and rAd-p53 + TP group, without statistically significant difference (p>0.05). The positive expression rate of iASPP was different and gradually declined in the RH group, TP group and rAd-p53 + TP group (p<0.05). Moreover, the positive expression rate of P-gp was also different among the 3 groups, and it was increased in the TP group, while it was decreased in the RH and rAd-p53 + TP group (p<0.05)., Conclusion: The intratumor injection of rAd-p53 into patients with cervical cancer is safe and effective, showing a new way in the gene therapy of cervical cancer. Both ASPP and P-gp may be potential biomarkers in the treatment of cervical cancer.

Photonic neural networks benefit from both the high-channel capacity and the wave nature of light acting as an effective weighting mechanism through linear optics. Incorporating a nonlinear activation function by using active integrated photonic components allows neural networks with multiple layers to be built monolithically, eliminating the need for energy and latency costs due to external conversion. Interferometer-based modulators, while popular in communications, have been shown to require more area than absorption-based modulators, resulting in a reduced neural network density. Here, we develop a model for absorption modulators in an electro-optic fully connected neural network, including noise, and compare the network's performance with the activation functions produced intrinsically by five types of absorption modulators. Our results show the quantum well absorption modulator-based electro-optic neuron has the best performance allowing for 96% prediction accuracy with 1.7×10 -12 J/MAC excluding laser power when performing MNIST classification in a 2 hidden layer feed-forward photonic neural network.

Graphene is a new kind of two-dimensional carbon nanomaterial with excellent properties and is promising for solid-phase microextraction (SPME). Plastic microtubes such as poly(tetrafluoroethylene) (PTFE) and poly(ether ether ketone) are ideal substrates for in-tube SPME. However, immobilization of graphene layers onto these materials is still a problem due to their nature of chemical resistance. In order to solve the problem, we proposed a novel method based on universal mussel-inspired polydopamine (PD) and layer-by-layer assembly of graphene in this work. To make a graphene assembly layer inside PTFE, the strategy includes two major steps. First, a PD layer is made on the PTFE surface by noncovalent interaction. Second, multilayer graphene is assembled on the PD layer by covalent interaction. By repeating these two steps, a functional graphene oxide (FGO)-modified PTFE tube with a controllable number of layers can be obtained. Morphology of the multilayer structure of graphene has been confirmed by scanning electronic microscopy. Formation of the covalent layer has also been characterized by Foourier transform infrared and X-ray photoelectron spectroscopy. It is very interesting that (FGO-PD)3-PTFE shows exceptional efficiency for SPME. Enrichment from 1082- to 2331-fold was achieved for six polyaromatic hydrocarbons (PAHs). An online SPME-HPLC-fluorescent detection method has been developed on the basis of (FGO-PD)3-PTFE. For qualitative analysis of PAHs, the method has low limits of detection of 0.05-0.1 pg/mL, which is significantly lower (up to 1000 times) than that reported in literature. The method shows wide linear range (0.3-200 pg/mL), good linearity (R(2) ≥ 0.9968), and good reproducibility (relative standard deviation < 3.4%). The method has been applied to determine PAHs in environmental samples. Good recoveries were obtained, ranging from 85.1% to 96.7%.