3D multi-robot olfaction in naturally ventilated indoor environments: Locating a time-varying source at unknown heights.

Source localization is significant for mitigating indoor air pollution and safeguarding the well-being and safety of occupants. While most study focuses on mechanical ventilation and static sources, this study explores the less-explored domain of locating time-varying sources in naturally ventilated spaces. We have developed an innovative 3D localization system that adjusts to varying heights, significantly enhancing capabilities beyond traditional fixed-height 2D systems. To ensure consistency in experimental conditions, we conducted comparative analyses of 2D and 3D methods, using a swinging fan to simulate natural ventilation. Our findings reveal a substantial disparity in performance: the 2D method had a success rate below 46.7% in cases of height mismatches, while our 3D methods consistently achieved success rates above 66.7%, demonstrating their superior effectiveness in complex environments. Furthermore, we validated the 3D strategies in real naturally ventilated settings, confirming their wider applicability. This research extends the scope of indoor source localization and offers valuable insights and strategies for more effective pollution control.

Binding of Carbon Monoxide to Hemoglobin in an Oxygen Environment: Force Field Development for Molecular Dynamics.

Carbon monoxide (CO) is a byproduct of the incomplete combustion of carbon-based fuels, such as wood, coal, gasoline, or natural gas. As incomplete combustion in a fire accident or in an engine, massively produced CO leads to a serious life threat because CO competes with oxygen (O2) binding to hemoglobin and makes people suffer from hypoxia. Although there is hyperbaric O2 therapy for patients with CO poisoning, the nanoscale mechanism of CO dissociation in the O2-rich environment is not completely understood. In this study, we construct the classical force field parameters compatible with the CHARMM for simulating the coordination interactions between hemoglobin, CO, and O2, and use the force field to reveal the impact of O2 on the binding strength between hemoglobin and CO. Density functional theory and Car-Parrinello molecular dynamics simulations are used to obtain the bond energy and equilibrium geometry, and we used machine learning enabled via a feedforward neural network model to obtain the classical force field parameters. We used steered molecular dynamics simulations with a force field to characterize the mechanical strength of the hemoglobin-CO bond before rupture under different simulated O2-rich environments. The results show that as O2 approaches the Fe2+ of heme at a distance smaller than ∼2.8 Å, the coordination bond between CO and Fe2+ is reduced to 50% bond strength in terms of the peak force observed in the rupture process. This weakening effect is also shown by the free energy landscape measured by our metadynamics simulation. Our work suggests that the O2-rich environment around the hemoglobin-CO bond effectively weakens the bonding, so that designing of O2 delivery vector to the site is helpful for alleviating CO binding, which may shed light on de novo drug design for CO poisoning.

Total Synthesis of Ganoderma Meroterpenoids Cochlearol B and Its Congeners Driven by Structural Similarity and Biological Homology.

Secondary metabolites that have the same biological origin must share some relationship in their biosynthesis. Exploring this relationship has always been a significant task for synthetic biologists. However, from the perspective of synthetic chemists, it is equally important to propose, prove, or refute potential biosynthetic pathways in order to elucidate and understand the biosynthesis of homologous secondary metabolites. In this study, driven by the high structural similarity between the homologous Ganoderma meroterpenoids cochlearol B and ganocin B, two chemically synthetic strategies were designed and investigated sequentially for the synthesis of cochlearol B from ganocin B. These strategies include intramolecular metal-catalyzed hydrogen atom transfer (MHAT) and intramolecular photochemical [2+2] cycloaddition. The aim was to reveal their potential biosynthetic conversion relationship using chemical synthesis methods. As a result, a highly efficient total synthesis of cochlearol B, cochlearol T, cochlearol F, as well as the formal total synthesis of ganocins A-B, and ganocochlearins C-D, has been achieved. Additionally, a novel synthetic approach for the synthesis of 6,6-disubstituted 6H-dibenzo[b,d]pyran and its analogues has been developed through palladium(II)-catalyzed Wacker-type/cross-coupling cascade reactions.

Theoretical study of graded-index fiber for beam quality improvement and SRS suppression.

A confined-doped graded-index fiber model was established with reference to Nufern's 42C ytterbium-doped fiber. The core NA of the fiber is ∼0.06; the doping/core/cladding diameter is 30/42/250 µm; and the gain ion doping distribution is double parabolic. Based on a forward tandem-pumped amplifier structure, the numerical simulation was carried out on the physics characters of the fiber model. The fourth-order Runge-Kutta method was used to solve the boundary value problem during the numerical simulation. The differences between the graded-index fiber (GIF) and the step-index fiber (SIF) were studied theoretically, and the results illuminated that the beam quality of the GIF was better than the SIF. The stimulated Raman scattering (SRS) power in the GIF was lower than that in the SIF. These results show that the GIF has great potential for increasing the laser output power while maintaining good beam quality and can provide theoretical guidance and reference to experimental research of the high-power fiber laser.

Efficient combinatorial optimization by quantum-inspired parallel annealing in analogue memristor crossbar.

Combinatorial optimization problems are prevalent in various fields, but obtaining exact solutions remains challenging due to the combinatorial explosion with increasing problem size. Special-purpose hardware such as Ising machines, particularly memristor-based analog Ising machines, have emerged as promising solutions. However, existing simulate-annealing-based implementations have not fully exploited the inherent parallelism and analog storage/processing features of memristor crossbar arrays. This work proposes a quantum-inspired parallel annealing method that enables full parallelism and improves solution quality, resulting in significant speed and energy improvement when implemented in analog memristor crossbars. We experimentally solved tasks, including unweighted and weighted Max-Cut and traveling salesman problem, using our integrated memristor chip. The quantum-inspired parallel annealing method implemented in memristor-based hardware has demonstrated significant improvements in time- and energy-efficiency compared to previously reported simulated annealing and Ising machine implemented on other technologies. This is because our approach effectively exploits the natural parallelism, analog conductance states, and all-to-all connection provided by memristor technology, promising its potential for solving complex optimization problems with greater efficiency.

Label-Free Imaging of Cell Apoptosis by a Light-Addressable Electrochemical Sensor.

Label-free electrochemical visualization of cancer cell apoptosis is essential for cancer therapies. In this work, we proposed a noninvasive imaging method using a light-addressable electrochemical sensor (LAES) for label-free imaging of drug-induced tumor cell apoptosis. The dynamic AC photocurrent changes on MCF-7 human breast adenocarcinoma cells after inducing by tamoxifen were imaged. And the reasons for photocurrent changes on the cells were explored by monitoring the changes in the ζ potentials of cells and Faradic impedance. The results demonstrated that the AC photocurrent on apoptotic MCF-7 cells increased, and the apoptosis degree of each cell was heterogeneous. Moreover, the AC photocurrent increase was attributed to the increased cell membrane permeability and the increased gap between the cell basal surface and the substrate caused by cell apoptosis. This study provides a brand new approach for label-free visualizing cell apoptosis heterogeneity, which has great potential in apoptosis-associated drug screening or drug efficacy evaluation.

Carbonized polydopamine layer-protected silicon substrates for light-addressable electrochemical sensing and imaging.

The application of silicon (Si) substrate as photoelectrode in light-addressable electrochemistry (LAE) is severely limited due to its ease of surface oxidation. The resulted silicon oxide (SiOx) layer is electronically insulating and blocks charge transfer between the electrode and electrolyte. Keeping the Si from being oxidized is a key challenge for its practical use as a semiconductor electrode. In this work, we find that by developing a thin layer of polydopamine film on the surface of Si substrate, followed by carbonization at 550 °C, the natural oxidation of Si substrate can be successfully forestalled. When applied as an electrode, it is further found that the carbonized polydopamine (cPDA) layer can also prevent anodic oxidation of Si. The cPDA layer-modified Si substrate exhibits good photoelectrochemical performance and great stability, with no obvious signal decrease under ambient environment over 32 h. Our work here provides a new modification strategy for anti-oxidation of Si substrate and it is promising in the application of light-addressable electrochemical sensing and imaging.

Pharmacokinetics and tissue distribution of five bioactive components in the Corydalis yanhusuo total alkaloids transdermal patch following Shenque acupoint application in rats assessed by ultra-performance liquid chromatography-tandem mass spectrometry.

The purpose of this study was to evaluate the pharmacokinetics and tissue distribution of the Corydalis yanhusuo total alkaloids transdermal patch (CTTP) following Shenque acupoint application in rats. The concentrations of corydaline, tetrahydropalmatine, tetrahydrocolumbamine, protopine, and dehydrocorydaline in rat plasma and various tissues were simultaneously detected by ultra-performance liquid chromatography-tandem mass spectrometry after Shenque acupoint administration of CTTP. Plasma, heart, liver, spleen, lung, and kidney tissue samples were collected at specific times and separated by gradient elution on an ACQUITY UPLC HSS T3 column (1.8 µm, 100 mm × 2.1 mm) with a mobile phase of 0.01% formic acid aqueous solution and acetonitrile-0.01% formic acid. The methodological results showed that the selectivity, linear range, accuracy, precision, stability, matrix effect, and extraction recovery of the established method met the requirements of biological sample analysis. The results indicated that CTTP following Shenque acupoint administration rapidly delivered adequate drug into rat blood and maintained an effective plasma level for a significantly longer time than non-acupoint administration. Furthermore, CTTP effectively reached the liver through Shenque acupoint administration and showed tissue selectivity. The data obtained could provide a prospect for the treatment of chronic pain with CTTP following Shenque acupoint application.

An integrated fecal microbiome and metabolome in rats reveal variations in gut microbiota and fecal metabolic phenotype of Semen Euphorbiae and Semen Euphorbiae Pulveratum.

Semen Euphorbiae (SE) is a toxic traditional Chinese medicine made from the dry or mature seed of Euphorbia lathyris L. Research demonstrates that the toxic side-effects from eating SE are associated with intestinal disturbance. By processing to produce Semen Euphorbiae Pulveratum (SEP), the toxicity is reduced, and diarrhea is attenuated. However, there are minimal studies on the differential effects between SE and SEP on microbiota and fecal metabolites. In this study, 16S rDNA sequencing and UPLC-Q-TOF/MS were interpreted with PCA and OPLS-DA multivariate analysis to understand the effect of SE and SEP on the gut microbiota and fecal metabolic phenotype in rats. Compared to the blank control group, the results showed that both SE and SEP were associated with increased microbes from the phylum Firmicutes and decreased Bacteroidetes, but the change was not as strong in the SEP administration group. Meanwhile, the fecal metabolism of rats also changed significantly, since 17 additional metabolites were detected in both groups, including amino acid metabolites, bacterial metabolites, and lipid metabolites. Our results indicate that the SEP administration group may reduce toxicity by differentially influencing intestinal metabolites and flora.

Visualization of electrochemical reactions on microelectrodes using light-addressable potentiometric sensor imaging.

Visualization of the electrochemical reaction is essential for comprehensively understanding the electrochemical reaction mechanism and precisely characterizing dynamic electrochemical processes. Herein, we propose a simple device that combines light-addressable potentiometric sensor (LAPS) imaging and microelectrodes to serve as a general electroanalysis platform for the label-free sensing and imaging of electrochemical reactions. In this device, two microelectrodes are assembled on the LAPS chip. Electrochemical reactions occurring on the microelectrodes can be qualitatively and quantitatively observed and visualized using a LAPS chip that is sensitive to the reaction products. Validations were performed to monitor the effect of water electrolysis and potassium ferrocyanide oxidation surrounding the microelectrodes, respectively. We believe that this study will provide an excellent platform for the visualization and monitoring of electrochemical reactions and broaden the application scope of LAPS imaging to a general electroanalysis tool that is widely applicable in several fields.

Construction of magnetic drug delivery system and its potential application in tumor theranostics.

Magnetic nanoparticles(NPs) are characterized by a rich variety of properties. Because of their excellent physical and chemical properties, they have come to the fore in biomedicine and other fields. The magnetic NPs were extensively studied in magnetic separation of cells, targeted drug delivery, tumor hyperthermia, chemo-photothermal therapy, magnetic resonance imaging (MRI) and other biomedical fields. Magnetic NPs are increasingly used in magnetic resonance imaging (MRI) based on their inherent magnetic targeting, superparamagnetic enzyme-like catalytic properties and nanoscale size. Poly(lactic-co-glycolic acid) (PLGA) is a promising biodegradable material approved by FDA and EU for drug delivery. Currently, PLGA-based magnetic nano-drug delivery systems have attracted the attention of researchers. Herein, we achieved the effective encapsulation of sized-controlled polyethylene glycol-3,4-dihydroxy benzyl-amine-coated superparamagnetic iron oxide nanoparticles (SPIO NPs) and euphorbiasteroid into PLGA nanospheres via a modified multiple emulsion solvent evaporation method (W1/O2/W2). NPs with narrow size distribution and acceptable magnetic properties were developed that are very useful for applications involving cancer therapy and MRI. Furthermore, SPIO-PLGA NPs enhanced the MRI T2 relaxation properties of tumor sites.The prepared SPIO NPs and magnetic PLGA nanospheres can be promising magnetic drug delivery systems for tumor theranostics. This study has successfully constructed a tumor-targeting and magnetic-targeting smart nanocarrier with enhanced permeability and retention, multimodal anti-cancer therapeutics and biodegradability, which could be a hopeful candidate for anti-tumor therapy in the future.

Robotic Versus Laparoscopic Gastrectomy for Gastric Cancer: A Mega Meta-Analysis.

Background: Laparoscopic gastrectomy and robotic gastrectomy are the most widely adopted treatment of choice for gastric cancer. To systematically assess the safety and effectiveness of robotic gastrectomy for gastric cancer, we carried out a systematic review and meta-analysis on short-term and long-term outcomes of robotic gastrectomy. Methods: In order to find relevant studies on the efficacy and safety of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) in the treatment of gastric cancer, numerous medical databases including PubMed, Medline, Cochrane Library, Embase, Google Scholar, and China Journal Full-text Database (CNKI) were consulted, and Chinese and English studies on the efficacy and safety of RG and LG in the treatment of gastric cancer published from 2012 to 2022 were screened according to inclusion and exclusion criteria, and a meta-analysis was conducted using RevMan 5.4 software. Results: The meta-analysis inlcuded 48 literatures, with 20,151 gastric cancer patients, including 6,175 in the RG group and 13,976 in the LG group, respectively. Results of our meta-analysis showed that RG group had prololonged operative time (WMD = 35.72, 95% CI = 28.59-42.86, P < 0.05) (RG: mean ± SD = 258.69 min ± 32.98; LG: mean ± SD = 221.85 min ± 31.18), reduced blood loss (WMD = -21.93, 95% CI = -28.94 to -14.91, P < 0.05) (RG: mean ± SD = 105.22 ml ± 62.79; LG: mean ± SD = 127.34 ml ± 79.62), higher number of harvested lymph nodes (WMD = 2.81, 95% CI = 1.99-3.63, P < 0.05) (RG: mean ± SD = 35.88 ± 4.14; LG: mean ± SD = 32.73 ± 4.67), time to first postoperative food intake shortened (WMD = -0.20, 95% CI = -0.29 to -0.10, P < 0.05) (RG: mean ± SD = 4.5 d ± 1.94; LG: mean ± SD = 4.7 d ± 1.54), and lower length of postoperative hospital stay (WMD = -0.54, 95% CI = -0.83 to -0.24, P < 0.05) (RG: mean ± SD = 8.91 d ± 6.13; LG: mean ± SD = 9.61 d ± 7.74) in comparison to the LG group. While the other variables, for example, time to first postoperative flatus, postoperative complications, proximal and distal mar gin, R 0 resection rate, mortality rate, conversion rate, and 3-year overall survival rate were all found to be statistically similar at P > 0.05. Conclusions: In the treatment of gastric cancer, robotic gastrectomy is a safe and effective procedure that has both short- and long-term effects. To properly evaluate the advantages of robotic surgery in gastric cancer, more randomised controlled studies with rigorous research methodologies are needed.

Characterization of diterpene metabolism in rats with ingestion of seed products from Euphorbia lathyris L. (Semen Euphorbiae and Semen Euphorbiae Pulveratum) using UHPLC-Q-Exactive MS.

Previous pharmacological studies have indicated that diterpenoids are the primary effective chemical cluster in the seeds of Euphorbia lathyris L. The seed products are used in traditional Chinese medicine in the forms of Semen Euphorbiae (SE) and Semen Euphorbiae Pulveratum (SEP). However, the metabolism of the plant's diterpenoids has not been well elucidated, which means that the in vivo metabolite products have not been identified. The current study screened the physiological metabolites of six diterpenes [Euphorbia factor L1 (L1), L2 (L2), L3 (L3), L7a (L7a), L7b (L7b), and L8 (L8)] in feces and urine of rats after oral administration of SE and SEP using UHPLC-Q-Exactive MS. A total of 22 metabolites were detected in feces and 8 in urine, indicating that the major elimination route of diterpenoids is via the colon. Hydrolysis, methylation, and glucuronidation served as the primary metabolic pathways of these diterpenoids. In sum, this study contributed to the elucidation of new metabolites and metabolic pathways of SE and SEP, and the new chemical identities can be used to guide further pharmacokinetic studies.

Morphological study of chronic prostatitis-chronic pelvic pain syndrome (CP/CPPS) normal modeling dose of T2 peptide in mice.

OBJECTIVES: However, the pathogenesis and etiology of CP/CPPS are still poorly understood. Therefore, there is a need for further research through the Image J software to develop models capable of imitating the pathogenesis and etiology of CP/CPPS with different doses of the pathogenesis and the etiology of CP/CPPS is still poorly understood. The aim was to determine the area of the prostatic interstitium, the localization of the inflammation, and the impact of different doses on the group model. MATERIALS AND METHODS: A total of 30 male ICR mice were randomly grouped into 5 (n = 6): 45 µg group = 6, 60  µg group = 6, 90  µg group = 6, 120  µg group = 6, 120  µg group = 6, control group = 6. With the exception of the control group, all the groups were immunized by injecting 0.2 mL of T2 peptide emulsion and immune adjuvant CFA to induce non-bacterial chronic prostatitis on days 0 and 14 of the mice and finally executed on day 28. All injections were administered subcutaneously. HE staining was used to evaluate changes in prostate pathology. Image J was used to calculate the area of the prostate interstitium, which represents the degree of prostate edema. To compare statistical differences between groups, the ANOVA test was used. RESULTS: From the perspective of pathological scoring, the 60 µg, 90  µg, and 120  µg groups had the highest scores using Image J to treat inflammatory cells. In addition, in the prostate interstitium area treated, it was found that the 90  µg group attained the largest prostate interstitial area as well as the highest degree of swelling. CONCLUSIONS: From the results, Image J software is an effective tool in the calculating the surface of the prostatic interstitium and the specific localization of the inflammation.

Metabonomics analysis of semen euphorbiae and semen Euphorbiae Pulveratum using UPLC-Q-TOF/MS.

Semen Euphorbiae (SE), the dry and mature seed of Euphorbia lathyris L., a common traditional Chinese medicine, has significant pharmacological activity. However, its toxicity limits its clinical application, and less toxic Semen Euphorbiae Pulveratum (SEP) is often used clinically. To explore the possible mechanism of SE frost-making and attenuation, this study used ultrahigh-performance liquid chromatography coupled with quadrupole time of flight mass spectrometry to perform a comprehensive metabolomics analysis of serum and urine samples from rats treated with SE and SEP, and performed histopathological evaluation of liver, kidney and colon tissues. Meanwhile, the different metabolites were visualized through multivariate statistical analysis and the HMDB and KEGG databases were used to distinguish the differential metabolites of SE and SEP to reveal related metabolic pathways and their significance. In total, 32 potential biomarkers, 14 in serum and 18 in urine, were identified. The metabolic pathway analysis revealed that arachidonic acid metabolism, sphingolipid metabolism, tyrosine and tryptophan biosynthesis, the tricarboxylic acid cycle and seven other metabolic pathways were significantly altered. Importantly, compared with SE, SEP reduced the metabolic disorder related to endogenous components. The mechanism may be related to the regulation of lipid metabolism, intestinal flora metabolites, amino acid metabolism and energy metabolism. This study provided new insights into the possible mechanism of SE freezing and attenuation.

A Homogeneous Label-Free Electrochemical microRNA Biosensor Coupling With G-Triplex/Methylene Blue Complex and λ-Exonuclease-Assisted Recycling Amplification.

A novel homogeneous label-free electrochemical biosensor using G-triplex/methylene blue (G3/MB) complex as the signal generator together with an amplification assisted by the λ-exonuclease (λ-Exo) has been successfully constructed for ultrasensitive microRNA (miRNA) detection. An integrated microelectrode was designed to realize the miniaturization of the homogeneous electrochemical assay. Taking advantage of G3, that can specifically bind with MB and decrease its diffusion current, a single-stranded functional DNA hairpin structure was designed as the bio-recognition probe. The probe consisted of G3, eight bases to block G3, and the complementary sequences of the target miRNA. Here we chose miRNA141-a potentially diagnostic biomarker of prostate cancer as the model target. The presence of miRNA141 could hybridize with the probe DNA to form a double-stranded structure with a 5'-phosphorylated terminus. Then λ-Exo was adopted to digest mononucleotides from the 5'-end, leading to the release of G3 part and miRNA141. The released miRNA could hybridize with another probe to trigger the cycling process, while the released G3 could therefore interact with MB to cause a detectable decrease of diffusion current. The proposed strategy showed a low detection limit of 16 fM and an excellent specificity to discriminate single-base mismatches. Furthermore, this sensor was applied to detect miRNA141 from diluted human serum samples, indicating that it has great potential in the application of nucleic acid detection in real samples.

Ligand-modified homologous targeted cancer cell membrane biomimetic nanostructured lipid carriers for glioma therapy.

The main treatment measure currently used for glioma treatment is chemotherapy; the biological barrier of solid tumors hinders the deep penetration of nanomedicines and limits anticancer therapy. Furthermore, the poor solubility of many chemotherapeutic drugs limits the efficacy of antitumor drugs. Therefore, improving the solubility of chemotherapeutic agents and drug delivery to tumor tissues through the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB) are major challenges in glioma treatment. Nanostructured lipid carriers (NLCs) have high drug loading capacity, high stability, and high in vivo safety; moreover, they can effectively improve the solubility of insoluble drugs. Therefore, in this study, we used solvent volatilization and ultrasonic melting methods to prepare dihydroartemisinin nanostructured lipid carrier (DHA-NLC). We further used the glioma C6 cancer cell (CC) membrane to encapsulate DHA-NLC owing to the homologous targeting mechanism of the CC membrane; however, the targeting ability of the CC membrane was weak. We accordingly used targeting ligands for modification, and developed a bionanostructured lipid carrier with BBB and BBTB penetration and tumor targeting abilities. The results showed that DHA-loaded NGR/CCNLC (asparagine-glycine-arginine, NGR) was highly targeted, could penetrate the BBB and BBTB, and showed good anti-tumor effects both in vitro and in vivo, which could effectively prolong the survival time of tumor-bearing mice. Thus, the use of DHA-loaded NGR/CCNLC is an effective strategy for glioma treatment and has the potential to treat glioma.

Comparison of Pharmacokinetics and Tissue Distribution Characteristics of Three Diterpenoid Esters in Crude and Prepared Semen Euphorbiae.

BACKGROUND: Semen Euphorbiae (SE) and Semen Euphorbiae Pulveratum (SEP) have a long history of medicinal use. SEP is the processed product of SE; both ancient and modern studies have shown that SEP has a lower toxicity compared to SE. To clarify the influence of processing on the pharmacological properties of SE and SEP, a study was carried out to compare the pharmacokinetics and distribution characteristics of three active compounds after oral administration of SE and SEP extracts. METHODS: A UPLC-MS/MS method was established to simultaneously determine the contents of Euphorbia factors L1, L2, and L3 in rat plasma and mouse tissues after an oral administration of crude and processed SE with approximately the same dosage. Plasma and heart, liver, spleen, lung, kidney, and colon tissue samples were treated with ethyl acetate and separated by gradient elution on a C18 column with a mobile phase of 0.1% formic acid and methanol. RESULTS: The established method had good selectivity, linear range, accuracy, precision, stability, matrix effect, and extraction recovery. The area under the concentration time curve, time to maximum concentration, maximum concentration, half-life of elimination, and mean retention time of plasma samples in SEP-treated group decreased, and the clearance in SEP-treated group increased. Moreover, the active component concentrations in colon, liver, and kidney tissues were more followed by those in the heart, lungs, and spleen. CONCLUSION: These results indicate that the processing could influence the pharmacokinetics and tissue distribution of Euphorbia factors L1, L2, and L3 after oral administration of crude and processed SE. The data obtained may lay a foundation for the clinical use of SE and for further study on the processing mechanism of SE.