Large detection range and high strain sensitivity fiber SPR sensor based on wave structure.

To achieve a fiber strain sensor with a large detection range and high sensitivity, this paper proposes a wave structured fiber SPR strain sensor. When subjected to axial strain, the wave structured fiber is stretched axially, increasing the stretchability of the sensor and achieving a large detection range strain sensing. Meanwhile, axial strain reduces the longitudinal amplitude of the fiber wave structure, effectively changing the total reflection angle of the transmitted beam at the peak and valley (SPR incidence angle) to achieve high sensitivity SPR strain sensing. The experiment indicates that the strain detection range of the sensor can reach 0-1800µÎµ, with a maximum strain sensitivity of 36.25pm/µÎµ. The wave structured fiber SPR strain sensor designed in this article provides a new approach to improve the range and sensitivity of strain detection.

Spiral cone fiber SPR sensor for detecting ginsenoside Rg1.

The conical fiber SPR sensor is easy to manufacture and has been used in biochemical detection research, but it has the problem of structural fragility. This article proposes a spiral cone fiber SPR sensor, which introduces a spiral structure on the 76µm fiber coarse cone, achieving good coupling of the core mode into the cladding mode, and improving the physical strength and practicality of the cone-shaped fiber SPR sensor. By modifying the target protein on the surface of the sensor gold film, specific detection of ginsenoside Rg1, an active ingredient of traditional Chinese medicine ginseng, was achieved. The detection sensitivity was 0.138 nm/(µm/ml) and the detection limit was 0.22µm/ml. The proposed spiral cone fiber SPR sensor provides a new scheme for the specific detection of active ingredients in traditional Chinese medicine, which is structurally stable and physically strong.

Metatranscriptomic data mining together with microfluidic card uncovered the potential pathogens and seasonal RNA viral ecology in a drinking water source.

AIMS: Despite metatranscriptomics becoming an emerging tool for pathogen surveillance, very little is known about the feasibility of this approach for understanding the fate of human-derived pathogens in drinking water sources. METHODS AND RESULTS: We conducted multiplexed microfluidic cards and metatranscriptomic sequencing of the drinking water source in a border city of North Korea in four seasons. Microfluidic card detected norovirus, hepatitis B virus (HBV), enterovirus, and Vibrio cholerae in the water. Phylogenetic analyses showed that environmental-derived sequences from norovirus GII.17, genotype C of HBV, and coxsackievirus A6 (CA6) were genetically related to the local clinical isolates. Meanwhile, metatranscriptomic assembly suggested that several bacterial pathogens, including Acinetobacter johnsonii and V. cholerae might be prevalent in the studied region. Metatranscriptomic analysis recovered 349 species-level groups with substantial viral diversity without detection of norovirus, HBV, and CA6. Seasonally distinct virus communities were also found. Specifically, 126, 73, 126, and 457 types of viruses were identified in spring, summer, autumn, and winter, respectively. The viromes were dominated by the Pisuviricota phylum, including members from Marnaviridae, Dicistroviridae, Luteoviridae, Potyviridae, Picornaviridae, Astroviridae, and Picobirnaviridae families. Further phylogenetic analyses of RNA (Ribonucleic Acid)-dependent RNA polymerase (RdRp) sequences showed a diverse set of picorna-like viruses associated with shellfish, of which several novel picorna-like viruses were also identified. Additionally, potential animal pathogens, including infectious bronchitis virus, Bat dicibavirus, Bat nodavirus, Bat picornavirus 2, infectious bursal disease virus, and Macrobrachium rosenbergii nodavirus were also identified. CONCLUSIONS: Our data illustrate the divergence between microfluidic cards and metatranscriptomics, highlighting that the combination of both methods facilitates the source tracking of human viruses in challenging settings without sufficient clinical surveillance.

Computer aided design of a single degree-of-freedom six-bar mechanism via Monte Carlo layered optimization method.

Planar single degree of freedom (DOF) 6-bar mechanisms, characterized by simple control and high stiffness, find extensive applications across various robotic systems. Nevertheless, the augmented quantity of design variables presents challenges in mechanism design, particularly when confronted with multiple constraints. This paper presents the implementation of computer-aided design for a single DOF 6-bar mechanism. Considering the characteristics of the 6-bar mechanism, a classified kinematics modeling method is proposed. Subsequently, a constraint index system is established, encompassing trajectory, posture, performance, and additional auxiliary variable constraints. A Monte Carlo layered optimization method is then proposed. The introduction of the constraint scaling coefficient divides the optimization process into multiple layers, wherein the constraint conditions are dynamically adjusted at each layer. The Monte Carlo method is integrated to screen initial values and determine the number of variables in each iteration, facilitating efficient optimization of the mechanism under multiple constraints. Building on this foundation, mechanism design software is developed to diminish reliance on experience. Numerous examples demonstrate the rapid acquisition of 6-bar mechanisms satisfying multiple constraints through the proposed method, showcasing exceptional computational efficiency. This study serves as a reference for different users seeking to accomplish the efficient design of 6-bar mechanisms.

Adipose-derived stem cells can alleviate RHDV2 induced acute liver injury in rabbits.

Rabbit hemorrhagic disease virus (RHDV) can cause fatal fulminant hepatitis, which is very similar to human acute liver failure. The aim of this study was to investigate whether adipose-derived stem cells (ADSCs) could alleviate RHDV2-induced liver injury in rabbits. Twenty 50-day-old rabbits were divided randomly into two groups (RHDV2 group, ADSCs + RHDV2 group). Starting from the 1st day, two groups of rabbits were given 0.5 ml of viral suspensions by subcutaneous injection in the neck. Meanwhile, the ADSCs + RHDV2 group was injected with ADSCs cell suspension (1.5 × 107 cells/ml) via a marginal ear vein, and the RHDV2 group was injected with an equal amount of saline via a marginal ear vein. At the end of the 48 h experiment, the animals were euthanized and gross hepatic changes were observed before liver specimens were collected. Histopathological analysis was performed using hematoxylin-eosin (HE), periodic acid schiff (PAS) and Masson's trichrome staining. For RHDV2 affected rabbits, HE staining demonstrated disorganized hepatic cords, loss of cellular detail, and severe cytoplasmic vacuolation within hepatocytes. Glycogen was not observed with PAS staining, and Masson's Trichrome staining showed increased hepatic collagen deposition. For rabbits treated with ADSCs at the time of inoculation, hepatic pathological changes were significantly less severe, liver glycogen synthesis was increased, and collagen fiber deposition was decreased. For RHDV2 affected rabbits, Tunel and immunofluorescence staining showed that the number of apoptotic cells, TGF-ß, and MMP-9 protein expression increased. And that in the ADSC treated group there was less hepatocyte apoptosis. In addition, RHDV2 induces liver inflammation and promotes the expression of IL-1ß, IL-6, and TNF-α. In rabbits administered ADSCs at time of inoculation, the expression of inflammatory factors in liver tissue decreased significantly. Our experiments show that ADSCs can protect rabbits from liver injury by RHDV2 and reduce the pathological and inflammatory response of liver. However, the specific protective mechanism needs further study.

Effect of ultrasonic vibration on oxide layer properties in ultrasonic-assisted ELID internal cylinder grinding.

The oxide film on the surface of the grinding wheel plays a very important role in ultrasonic-assisted electrolytic in-process dressing (UA-ELID) grinding. In order to investigate the influence of ultrasonic vibration on the characteristics of oxide film on the surface of grinding wheel in compound grinding, the formation mechanism of oxide film on the surface of grinding wheel under ultrasonic action was analyzed theoretically from two aspects: the change of single grain trajectory caused by ultrasonic vibration and the effect of ultrasonic cavitation. The pre-dressing tests were conducted with different pre-dressing times to observe the oxide layer properties at different pre-dressing stages. The grinding tests were conducted after pre-dressing to verify the grinding performance of oxide layer under different pre-dressing methods. The results show that after the ultrasonic vibration of the grinding wheel is added during electrolytic in-process dressing (ELID) process, the holes and cracks of the oxide film on the surface of the grinding wheel are greatly reduced during the whole pre-dressing process. In addition, the pre-dressing current decreases more stably and the current is smaller when it reaches stability. After the pre-dressing, the thickness of the oxide film is reduced by about 35 % and the hardness is increased by about 70 % compared with the ordinary pre-dressing process. The grinding test results show that the oxide film obtained by ultrasonic vibration of the additional grinding wheel is more conducive to improving the surface quality of the grinding process. Therefore, compared with the ordinary pre-dressing process, the density and uniformity of oxide film on the surface of grinding wheel is better and the hardness is higher after the additional ultrasonic vibration of grinding wheel. It is beneficial to improve the surface quality of workpiece.

Tailored wastewater surveillance framework uncovered the epidemics of key pathogens in a Northwestern city of China.

Wastewater surveillance enables rapid pathogen monitoring and community prevalence estimation. However, how to design an integrated and tailored wastewater surveillance framework to monitor major health threats in metropolises remains a major challenge. In this study, we first analyzed the historical clinical data of Xi'an city and designed a wastewater surveillance framework covering five key endemic viruses, namely, SARS-CoV-2, norovirus, influenza A virus (IAV), influenza B virus (IBV), respiratory syncytial virus (RSV), and hantavirus. Amplicon sequencing of SARS-CoV-2, norovirus and hantavirus was conducted biweekly to determine the prevalent community genotypes circulating in this region. The results showed that from April 2023 to August 2023, Xi'an experienced two waves of SARS-CoV-2 infection, which peaked in the middle of May-2023 and late August-2023. The sewage concentrations of IAV and RSV peaked in early March and early May 2023, respectively, while the sewage concentrations of norovirus fluctuated throughout the study period and peaked in late August. The dynamics of the sewage concentrations of SARS-CoV-2, norovirus, IAV, RSV, and hantavirus were in line with the trends in the sentinel hospital percent positivity data, indicating the role of wastewater surveillance in enhancing the understanding of epidemic trends. Amplicon sequencing of SARS-CoV-2 revealed a transition in the predominant genotype, which changed from DY.1 and FR.1.4 to the XBB and EG.5 subvariants. Amplicon sequencing also revealed that there was only one predominant hantavirus genotype in the local population, while highly diverse genotypes of norovirus GI and GII were found in the wastewater. In conclusion, this study provided valuable insights into the dynamics of infection trends and predominant genotypes of key pathogens in a city without sufficient clinical surveillance, highlighting the role of a tailored wastewater surveillance framework in addressing public health priorities. More importantly, our study provides the first evidence demonstrating the applicability of wastewater surveillance for hantavirus, which is a major health threat locally.

Protective effect of selenomethionine on rabbit testicular injury induced by Aflatoxin B1.

The aim of this study was to investigate the alleviating effect of selenomethionine (SeMet) on aflatoxin B1 (AFB1)-induced testicular injury in rabbits. Twenty-five 90-d-old rabbits were randomly divided into 5 groups (the control group, the AFB1 group, the 0.2 mg/kg SeMet + AFB1 group, the 0.4 mg/kg SeMet + AFB1 group and the 0.6 mg/kg SeMet + AFB1 group). After 1 d of the experiment, the SeMet-treated groups were fed 0.2 mg/kg SeMet, 0.4 mg/kg SeMet, or 0.6 mg/kg SeMet daily, and the remaining two groups were fed a normal diet for 30 d. On Day 31, all rabbits in the model group and the three treatment groups were fed 0.5 mg/kg AFB1 for 21 d. The levels of testosterone (T), luteinizing hormone (LH) and follicle stimulating hormone (FSH) in rabbit plasma were detected. Rabbit semen was collected, and its quality was evaluated. Pathological changes in rabbit testes were observed by hematoxylin-eosin (HE) staining. The expression of related proteins in testicular tissue was detected by immunohistochemistry, immunofluorescence and western blot (WB) analysis. Enzyme-linked immunosorbent assays (ELISAs) were used to detect oxidative stress-related indices and inflammatory factors in testicular tissue. The results showed that AFB1 can induce oxidative stress and inflammation to activate the p38/MSK/NF-κB signalling pathway, mediate apoptosis, inhibit the proliferation and differentiation of testicular cells, destroy the integrity of the blood-testis barrier (BTB) and the normal structure of the testis, and reduce the content of sex hormones and semen quality. SeMet pretreatment significantly alleviated testicular injury oxidative stress, and the inflammatory response in rabbits. Thus, we demonstrated that SeMet restores AFB1-induced testicular toxicity by inhibiting the p38/MSK/NF-κB signalling pathway. In addition, in this study, 0.4 mg/kg SeMet had the most impactful effect.

Wastewater surveillance together with metaviromic data revealed the unusual resurgence of infectious diseases after the first wave of the COVID-19 outbreak.

How to address public health priorities after COVID-19 is becoming a critical task. To this end, we conducted wastewater surveillance for six leading pathogens, namely, SARS-CoV-2, norovirus, rotavirus, influenza A virus (IAV), enteroviruses and respiratory syncytial virus (RSV), in Nanchang city from January to April 2023. Metaviromic sequencing was conducted at the 1st, 4th, 7th, 9th, 12th and 14th weeks to reveal the dynamics of viral pathogens that were not covered by qPCR. Amplicon sequencing of the conserved region of norovirus GI and GII and the rotavirus and region encoding nonstructural protein of RSV was also conducted weekly. The results showed that after a rapid decrease in SARS-CoV-2 sewage concentrations occurred in January 2023, surges of norovirus, rotavirus, IAV and RSV started at the 6th, 7th, 8th and 11th weeks, respectively. The dynamics of the sewage concentrations of norovirus, rotavirus, IAV and RSV were consistent with the off-season resurgence of the above infectious diseases. Notably, peak sewage concentrations of norovirus GI, GII, rotavirus, IAV and RSV were found at the 6th, 3rd, 7th, 7th and 8th weeks, respectively. Astroviruses also resurge after the 7th week, as revealed by metaviromic data, suggesting that wastewater surveillance together with metaviromic data provides an essential early warning tool for revealing patterns of infectious disease resurgence.

Landscape of tumoral ecosystem for enhanced anti-PD-1 immunotherapy by gut Akkermansia muciniphila.

Gut Akkermansia muciniphila (Akk) has been implicated in impacting immunotherapy or oncogenesis. This study aims to dissect the Akk-associated tumor immune ecosystem (TIME) by single-cell profiling coupled with T cell receptor (TCR) sequencing. We adopted mouse cancer models under anti-PD-1 immunotherapy, combined with oral administration of three forms of Akk, including live Akk, pasteurized Akk (Akk-past), or its membrane protein Amuc_1100 (Amuc). We show that live Akk is most effective in activation of CD8 T cells by rescuing the exhausted type into cytotoxic subpopulations. Remarkably, only live Akk activates MHC-II-pDC pathways, downregulates CXCL3 in Bgn(+)Dcn(+) cancer-associated fibroblasts (CAFs), blunts crosstalk between Bgn(+)Dcn(+) CAFs and PD-L1(+) neutrophils by a CXCL3-PD-L1 axis, and further suppresses the crosstalk between PD-L1(+) neutrophils and CD8 T cells, leading to the rescue of exhausted CD8 T cells. Together, this comprehensive picture of the tumor ecosystem provides deeper insights into immune mechanisms associated with gut Akk-dependent anti-PD-1 immunotherapy.

Wave type fiber SPR sensor for rapid and highly sensitive detection of hyperoside.

The fiber surface plasmon resonance (SPR) sensor used for the detection of active ingredients in traditional Chinese medicine has the problems of low sensitivity and difficult specific recognition. This paper proposed a wave type fiber SPR sensor, which reduced the mode of transmitted light through a periodic wave structure and caused concentrated and total reflection of the transmitted beam at the interface between the bent peak cladding and the air. A 50 nm gold film was coated on the surface of the cladding in the wave structure area to form the SPR sensing area. By controlling the width and height of the wave structure to control the total reflection angle of the transmitted light, i.e., the SPR incidence angle, the sensitivity of the fiber SPR sensor was effectively improved to 4972 nm/RIU. Furthermore, HSP90AA protein was modified on the gold film of the sensor to achieve specific detection of hyperoside. The longest single detection time was only 3 minutes, and the detection sensitivity was 0.53 nm/(µg/ml), with a detection limit as low as 0.68µg/ml, which is comparable to liquid chromatography. The proposed wave type fiber SPR sensor is fast in production and has high structural mechanical strength, providing a new approach for the rapid, highly sensitive, and specific detection of active ingredients in traditional Chinese medicine.

Fe-Bi dual sites regulation of Bi2O2.33 nanosheets to promote photocatalytic nitrogen fixation activity.

In the process of photocatalytic ammonia synthesis, efficient activation of nitrogen molecules constitutes a fundamental challenge. During the N2 activation, the close interdependence between the acceptance and donation of electron results in their mutual limitation, leading to high energy barrier for N2 activation and unsatisfactory photocatalytic performance. This work decoupled the electron acceptance and donation processes by constructing Fe-Bi dual active sites, resulting in enhancing N2 activation through the high electron trapping ability of Fe3+ and strong electron donating ability of Bi2+. The photocatalytic nitrogen reduction efficiency of 3%Fe/Bi2O2.33 (118.71 µmol gcat-1h-1) is 5.3 times that of Bi2O2.33 (22.41 µmol gcat-1h-1). In-situ Fourier transform infrared (In situ FTIR) spectroscopy and density functional theory (DFT) calculations manifest that Fe3+-Bi2+ dual active sites work together to promote nitrogen adsorption and activation, and the reaction path is more inclined toward alternate hydrogenation path. N2 adsorption and activation properties are optimized by heteronuclear bimetallic active sites, which offers a new way for the rational design of nitrogen-fixing photocatalysts.

Effect of the Sr-Fe layered double hydroxide coating based on the microenvironment response on implant osseointegration in osteoporotic rats.

Osteoporosis is a disease that manifests itself as an abnormality of bone metabolism and is characterized by low bone mass and destruction of the bone microstructure. Since bone resorption occurs more rapidly than new bone formation, osteoporosis leads to reduced orthopedic implant stability. From a microenvironmental point of view, the rationale for this outcome is that osteoclasts are overactive in the bone tissue of patients with osteoporosis, and the large amount of H+ they produce leads to local chronic acidosis, which promotes bone mineral loss. Therefore, we designed a weakly alkaline layered double hydroxide (LDH) coating to modulate the pathologically acidic microenvironment and the osteogenic-osteoclastic coupling by releasing Sr2+. We prepared Sr-Fe LDH coatings on pure titanium implants using a hydrothermal method in this study and characterized the material using SEM, AFM, XRD, XPS, EDS, ICP, pH acidimeter, etc. We found that the coatings had good nanomorphology and were able to efficiently neutralize H+ as well as steadily release Sr2+ for up to 21 days. In vitro, the coating not only significantly promoted the adhesion, proliferation, and differentiation of osteoblasts, but also inhibited the differentiation of osteoclasts at the same time. In addition, in animal experiments, the coating significantly improved the mechanical stability of the implant in osteoporotic rats, increasing Sr-Fe LDH@Ti maximal push-out force by 72.2% compared to Ti. At the same time, the coating was effective in reversing the osteoporotic state, resulting in a 58.5% increase in BV/TV (%), and a 12.4% increase in Tb. N (1 mm-1), a 31.6% increase in Tb. Th (µm), and a 30.9% increase in BA (%). Our results suggest that this Sr-Fe LDH nanocoating material with acid-neutralizing, as well as long-term Sr2+-releasing capabilities, is a novel and effective orthopedic implant coating material under osteoporotic conditions.

Evaluation of antiarthritic activity of ginkgolic acid against Freund's adjuvant induced arthritic rat model

This study aimed to analyze the antiarthritic activity of ginkgolic acid against the Complete Freund's Adjuvant (CFA)-induced arthritis in rats. Arthritis was induced through an intradermal injection of CFA (0.1 mL) at the right hind footpad of adult Wistar Albino rats. Ginkgolic acid was administered orally at doses of 25 mg/kg and 50 mg/kg, respectively, once daily via gavage for 25 days upon inducing arthritis. Indomethacin was administered orally at a dose of 3 mg/kg twice in a week which served as positive control group. The animals were sacrificed and subjected to biochemical and histopathological analysis upon completion of treatment. Ginkgolic acid was able to reverse the arthritic effect (p < 0.01) induced by CFA in a dose dependent manner. Swelling of paw, thymus and spleen index, serum biomarker levels, and pro-inflammatory cytokines were significantly reduced (p < 0.01) by the acid whereas the antioxidant enzyme activities were remarkably restored. The histopathological findings were in agreement with the biochemical results. The results indicate that the antioxidant and anti-inflammatory properties of ginkgolic acid can be credited to the antiarthritic effects, and it can be promoted as a potential agent for therapeutic use against osteoarthritis