Widely targeted metabolomics combined with E-tongue and E-nose reveal dynamic changes of tender coconut water in responses to the infection of Ceratocystis paradoxa.

Ceratocystis paradoxa is a major cause of postharvest disease in tender coconuts worldwide. We conducted a comprehensive study using widely targeted metabolomics, electronic tongue (E-tongue), and electronic nose (E-nose) analyses to investigate the impacts of C. paradoxa invasion on the quality of tender coconut water (TCW) from fresh control (FC), uninoculated (UN), skin-inoculated (SI), and deep-inoculated (DI) nuts. DI exhibited significantly higher taste indicators associated with bitterness, saltiness, astringency aftertaste, and bitter aftertaste, as well as odor sensor values related to various compounds such as long-chain alkanes, hydrides, methane, organic sulfides, etc. Invasion of C. paradoxa into the endosperm altered the flavor characteristics of TCW mainly through the modulation of carbohydrate and secondary metabolite pathways. Furthermore, significant correlations were observed between the differentially expressed flavorful metabolites and the sensor indicators of the E-nose and E-tongue. These findings offer valuable insights into understanding the impact of C. paradoxa infection on coconuts.

Potential of Near-Infrared Spectroscopy (NIRS) for Efficient Classification Based on Postharvest Storage Time, Cultivar and Maturity in Coconut Water.

Coconut water (CW) is a popular and healthful beverage, and ensuring its quality is crucial for consumer satisfaction. This study aimed to explore the potential of near-infrared spectroscopy (NIRS) and chemometric methods for analyzing CW quality and distinguishing samples based on postharvest storage time, cultivar, and maturity. CW from nuts of Wenye No. 2 and Wenye No. 4 cultivars in China, with varying postharvest storage time and maturities, were subjected to NIRS analysis. Partial least squares regression (PLSR) models were developed to predict reducing sugar and soluble sugar contents, revealing moderate applicability but lacking accuracy, with the residual prediction deviation (RPD) values ranging from 1.54 to 1.83. Models for TSS, pH, and TSS/pH exhibited poor performance with RPD values below 1.4, indicating limited predictability. However, the study achieved a total correct classification rate exceeding 95% through orthogonal partial least squares discriminant analysis (OPLS-DA) models, effectively discriminating CW samples based on postharvest storage time, cultivar, and maturity. These findings highlight the potential of NIRS combined with appropriate chemometric methods as a valuable tool for analyzing CW quality and efficiently distinguishing samples. NIRS and chemometric techniques enhance quality control in coconut water, ensuring consumer satisfaction and product integrity.

Synthesis of Multicolor Carbon Dots Catalyzed by Inorganic Salts with Tunable Nonlinear Optical Properties.

The nonlinear optical properties of carbon dots have been in the spotlight in recent years. In light of the complexity and diversity of factors affecting the nonlinear optical properties of carbon dots, how to reveal the origin and physical mechanism of the nonlinear optical properties of carbon dots accurately has become a problem. In this work, a template-free method was designed to prepare carbon dots via solid-phase reaction with phloroglucinol as a single carbon source and sodium bisulfate as the catalyst. This method is simple, green, safe, and easy to be prepared on a large scale. Three carbon dots with different luminous colors were obtained by simply adjusting the reaction temperature. The rise of reaction temperature affects the surface functional groups, and then hinders the luminescence of surface states, leading to the change of luminescence properties. The nonlinear optical properties of carbon dots were analyzed by the Z-scan technique. Surprisingly, all carbon dots have nonlinear optical responses, but there are differences in performance. Results prove the increase in sp2 domains may contribute to the significant improvement of the nonlinear optical properties of carbon dots, indicating a direction to improve the nonlinear optical properties of carbon dots.

In-Situ Growth of Mn3 O4 Nanoparticles on Nitrogen-Doped Carbon Dots-Derived Carbon Skeleton as Cathode Materials for Aqueous Zinc Ion Batteries.

Mn3 O4 is a promising cathode material for aqueous zinc ion batteries (ZIBs) which is a new type of low cost, eco-friendly, high security energy storage system, while those previously reported electrochemical capacities of Mn3 O4 are far from its theoretical value. In this work, Mn3 O4 nanoparticles and nitrogen-doped carbon dots (NCDs) are synthesized together through an in-situ hydrothermal route, and then calcined to be a nanocomposite in which Mn3 O4 nanoparticles are anchored on a nitrogen-doped carbon skeleton (designated as Mn3 O4 /NCDs). Although the carbon content is only 3.9 wt.% in the Mn3 O4 /NCDs, the NCDs-derived carbon skeleton provides an electrically conductive network and a stable structure. Such a special nanocomposite has a large specific surface area, plenty of active sites, excellent hydrophilicity and good electronic conductivity. Owing to these structural merits, the Mn3 O4 /NCDs electrode exhibits a preeminent specific capacity of 443.6 mAh g-1 and 123.3 mAh g-1 at current densities of 0.1 and 1.5 A g-1 in ZIBs, respectively, which are far beyond the bare Mn3 O4 nanoparticles synthesized under the similar condition. The electrochemical measurement results prove that carbon dots, as a new type of carbon nanomaterials, have strong ability to modify and improve the performance of existing electrode materials, which may push these electrode materials forward to practical applications.

Red Fluorescent Carbon Dot Powder for Accurate Latent Fingerprint Identification using an Artificial Intelligence Program.

Development and comparison of the latent fingerprints (LFPs) are two major studies in detection and identification of LFPs, respectively. However, integrated research studies on both fluorescent materials for LFP development and digital-processing programs for LFP comparison are scarcely seen in the literature. In this work, highly efficient red-emissive carbon dots (R-CDs) are synthesized in one pot and mixed with starch to form R-CDs/starch phosphors. Such phosphors are comparable with various substrates and suitable for the typical powder dusting method to develop LFPs. The fluorescence images of the developed LFPs are handled with an artificial intelligence program. For the optimal sample, this program presents an excellent matching score of 93%, indicating that the developed sample has very high similarity with the standard control. Our results are significantly better than the benchmark obtained by the traditional method, and thus, both the R-CDs/starch phosphors and the digital processing program fit well for the practical applications.

Genetic Transformation and Green Fluorescent Protein Labeling in Ceratocystis paradoxa from Coconut.

Ceratocystis paradoxa, the causal agent of stem-bleeding disease of the coconut palm, causes great losses to the global coconut industry. As the mechanism of pathogenicity of C. paradoxa has not been determined, an exogenous gene marker was introduced into the fungus. In this study, pCT74-sGFP, which contains the green fluorescent protein (GFP) gene, and the hygromycin B resistance gene as a selective marker, was used as an expression vector. Several protoplast release buffers were compared to optimize protoplast preparation. The plasmid pCT74-sGFP was successfully transformed into the genome of C. paradoxa, which was verified using polymerase chain reaction and green fluorescence detection. The transformants did not exhibit any obvious differences from the wild-type isolates in terms of growth and morphological characteristics. Pathogenicity tests showed that the transformation process did not alter the virulence of the X-3314 C. paradoxa strain. This is the first report on the polyethylene glycol-mediated transformation of C. paradoxa carrying a 'reporter' gene GFP that was stably and efficiently expressed in the transformants. These findings provide a basis for future functional genomics studies of C. paradoxa and offer a novel opportunity to track the infection process of C. paradoxa.

Efficient Oxygen Electrocatalyst for Zn-Air Batteries: Carbon Dots and Co9S8 Nanoparticles in a N,S-Codoped Carbon Matrix.

Non-noble metal-based bifunctional electrocatalysts for both oxygen reduction reactions (ORRs) and oxygen evolution reactions (OERs) are an essential component of high-performance rechargeable Zn-air batteries (ZABs). Herein, we report a novel and simple method for preparing Co9S8 nanoparticles embedded in N and S codoped carbon materials with aid of carbon dots (CDs). CDs play a key role in distributing Co9S8 nanoparticles in the matrix uniformly and enhancing the specific surface area and the electric conductivity simultaneously. The obtained Co9S8/CD@NSC exhibits an excellent ORR and OER bifunctional catalytic activity and a great long-term durability, with a half-wave potential of 0.84 V versus reversible hydrogen electrode (RHE) for the ORR and a low potential of 1.62 V versus RHE at 10 mA cm-2, which outperform the popular Pt/C and RuO2 commercial catalysts. Moreover, the Co9S8/CD@NSC catalyst also displays a superior activity and cycling stability as a cathode material in ZABs, which is far better than Pt/C + RuO2 mixture catalysts. Such a ZAB shows a low charge/discharge voltage gap of 0.62 V and great cycling stability over 125 h at 10 mA cm-2.

Robust Negative Electrode Materials Derived from Carbon Dots and Porous Hydrogels for High-Performance Hybrid Supercapacitors.

Hybrid supercapacitors generally show high power and long life spans but inferior energy densities, which are mainly caused by carbon negative electrodes with low specific capacitances. To improve the energy densities, the traditional methods include optimizing pore structures and modifying pseudocapacitive groups on the carbon materials. Here, another promising way is suggested, which has no adverse effects to the carbon materials, that is, constructing electron-rich regions on the electrode surfaces for absorbing cations as much as possible. For this aim, a series of hierarchical porous carbon materials are produced by calcinating carbon dots-hydrogel composites, which have controllable surface states including electron-rich regions. The optimal sample is employed as the negative electrode to fabricate hybrid supercapacitors, which show remarkable specific energy densities (up to 62.8-90.1 Wh kg-1 ) in different systems.

Red-Emissive Carbon Dots for Fingerprints Detection by Spray Method: Coffee Ring Effect and Unquenched Fluorescence in Drying Process.

Brightly red fluorescent carbon dots are synthesized hydrothermally and dissolved in diluted hydrochloric acid solution. Such carbon dots exhibit excitation-independent emission at about 620 nm with quantum yield over 10%, which is visible in daylight. After the carbon dots solution is sprayed to the fingerprints on various solid substrates and dried in air, clear fingerprints can be seen under an ultraviolet lamp and stay stable for 1 day. Detailed characterizations suggest that during the drying process, the coffee-ring effect and the electrostatic interactions between the carbon dots and the fingerprint residues prevent the typical aggregation-induced fluorescence quenching of carbon dots.

Frozen section and electron microscopy studies of the infection of the red palm weevil, Rhynchophorus ferrugineus (coleoptera:curculionidae) by the entomopathogenic fungus Metarhizium anisopliae.

This study determined the pathogenicity of Metarhizium anisopliae strain SD-3 against invasive red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (coleoptera:curculionidae) larvae in Hainan Province, China. Inoculation of 1 × 108 conidia/mL caused 100 % mortality of R. ferrugineus, indicating that the conidia of strain SD-3 were highly virulent. The process of invasion mechanism was showed by scanning electron microscopy (SEM) and frozen section as follows. Once R. ferrugineus was infected by strain SD-3, M. anisopliae hyphae first invaded the cuticular and body cavity of R. ferrugineus. Secondly, well-developed muscles, fat, tracheaes and digestive tube tissues in the abdomen of R. ferrugineus were then decomposed and absorbed by M. anisopliae hyphae, leading to the total destruction of the larvae. Finally, M. anisopliae hyphae reproduced, resulting in a large number of conidia in the body of RPW. The SEM and frozen section are convenient tools to observe the mode of action of entomopathogenic fungi and to observe how M. anisopliae is able to colonize and infect the host.

Screening of tropical isolates of Metarhizium anisopliae for virulence to the red palm weevil Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae).

The red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) is a serious pest of the palm tree in tropical regions of the world. One strain of Metarhizium sp. ZJ-1, isolated from Chinese soils, was evaluated for growth characteristics, and screened for its virulence to R. ferrugineus larvae in laboratory conditions. An approximately 685-bp fragment was amplified by ITS (ITS1-5.8S-ITS2) PCR from strain ZJ-1, further phylogenetic analysis revealed that 93 % similarity to Metarhizium anisopliae. Inoculation of 1 × 10(8) conidia/mL caused 100 % mortality of R. ferrugineus, LT50 levels of ZJ-1 were 1.66 days (1 × 10(8) conidia/mL), indicating that the conidia of strain ZJ-1 were highly virulent. These results suggest that M. anisopliae ZJ-1 has potential as an effective and persistent biological control agent for R. ferrugineus.

Emergency Department Use and Postvisit Care for Anxiety and Stress Disorders Among Children: A Population-Based Cohort Study in Alberta, Canada.

OBJECTIVE: We examined sociodemographic trends in emergency department ED visits and postvisit health care for anxiety and stress disorders. METHODS: Emergency department visits (N = 11,289) by children younger than 18 years were extracted from population-based administrative databases from Alberta, Canada (2002-2011). We examined health services use by demographics and socioeconomic proxy (First Nations status, family subsidy type: government, human services program, none). We calculated visit rates and described physician visits after discharge (n = 8075 children). Multivariable survival analyses (with 95% confidence intervals [CIs]) estimate time to first physician visit and ED return. RESULTS: During 2002-2011, visit rates increased by age, First Nations, and subsidy status. The largest increase was for children (all ages) from families receiving government subsidy (491.43/100,000, P < 0.001). Thirty days after an index visit, most physician follow-up visits were made by children aged 15 to 17 years (61.0%) and from families receiving no subsidy (66.5%). The median time to physician follow-up for First Nations children was 32 days (95% CI, 27-37) compared with 19 days for children from families receiving government subsidy whose median time was shortest (95% CI, 18-23). Children (all ages) in the government and human services program subsidy groups and those who had First Nations status returned earlier to the ED compared with children in the no subsidy group. CONCLUSIONS: Adolescents had high ED use and physician follow-up, whereas First Nations children and those from families receiving subsidy (all ages) had high ED use and low physician follow-up. Efforts to improve disorder identification and treatment among high ED user groups and low physician follow-up user groups are needed.

Histiocytic sarcoma combined with acute monocytic leukemia: a case report.

BACKGROUND: Histiocytic sarcoma (HS) is a rare malignant tumor. Underlying or associated disorders have been reported in some patients with HS. We herein report a very rare case of HS combined with acute monocytic leukemia (AMoL). CASE PRESENTATION: A 62-year-old man presented with systemic lymph node enlargement and pancytopenia in August 2012. Bone marrow (BM) aspirate showed abnormal hematopoiesis with 3% blast, but no obvious abnormalities on flow cytometric immunophenotyping. A BM cytogenetic study and fluorescence in situ hybridization revealed a 46, XY karyotype and no myelodysplastic syndrome-associated features, respectively. A right cervical node biopsy showed disrupted node structure with diffuse pleomorphic neoplastic cells that were positive for cluster of differentiation (CD) 68, MAC387 and lysozyme, but negative for CD1a, CD21, CD30, S100, and T-cell, B-cell, and myeloid lineage markers. The patient was diagnosed with HS and treated with 8 courses of CHOP chemotherapy. After 4 courses, total-body FDG-PET imaging showed partial remission and disappearance of abnormal hematopoiesis in the BM, but 2% blasts remained. Lymphadenopathy and pancytopenia recurred 1 month after the his last chemotherapy dose. He became resistant to second-line chemotherapy, with gradually increasing leukocytes, up to 50% blasts in BM in December 2013, and abnormal cells positive for CD117, CD13, CD33, HLA-DR, CD34, CD11c, CD38, and myeloperoxidase. He was diagnosed with acute monocytic leukemia (AMoL-M5), and treated by CAG regimen + decitabine, but died of severe pneumonia and hepatic failure. CONCLUSION: To our knowledge, this is the first case of HS combined with AMoL. The coexistence of these two neoplasms was shown by the lymph node biopsy findings and BM myeloid markers. The patient had a transient response to chemotherapy and a poor prognosis. Whether these two neoplasms were related is unclear; however, if so, we suspect the combination might be caused by a malignant transformation of a promonocyte or stem cell, upstream of histiocytes and monocytes.

Nickel Hydroxide-Modified Sulfur/Carbon Composite as a High-Performance Cathode Material for Lithium Sulfur Battery.

Tailored sulfur cathode is vital for the development of a high performance lithium-sulfur (Li-S) battery. A surface modification on the sulfur/carbon composite would be an efficient strategy to enhance the cycling stability. Herein, we report a nickel hydroxide-modified sulfur/conductive carbon black composite (Ni(OH)2@S/CCB) as the cathode material for the Li-S battery through the thermal treatment and chemical precipitation method. In this composite, the sublimed sulfur is stored in the CCB, followed by a surface modification of Ni(OH)2 nanoparticles with size of 1-2 nm. As a cathode for the Li-S battery, the as-prepared Ni(OH)2@S/CCB electrode exhibits better cycle stability and higher rate discharge capacity, compared with the bare S/CCB electrode. The improved performance is largely due to the introduction of Ni(OH)2 surface modification, which can effectively suppress the "shuttle effect" of polysulfides, resulting in enhanced cycling life and higher capacity.

Interaction of Anthracycline 3'-azido-epirubicin with Calf Thymus DNA via Spectral and Molecular Modeling Techniques.

Anthracycline antibiotics are extensively applied to clinical antitumor therapy. The binding mode and mechanism of a new anthracycline 3'-azido-epirubicin (AEPI) with calf thymus deoxyribonucleic acid (ctDNA) were investigated employing multiple spectroscopy techniques in Tris-HCl buffer solution (pH 7.4). Effect of pH on the interaction was provided to determine the proper environment for whole research. Iodide quenching studies and fluorescence polarization measurement indicated that ctDNA quenched the fluorescence of AEPI significantly via intercalation binding mode. The binding constants and binding sites for the interaction were calculated. From binding constant dependence on the temperature, static quenching mechanism of AEPI by ctDNA was confirmed based on the Stern-Volmer equation. Additionally, the thermodynamic parameters for the reaction revealed that the van der Waals force and hydrogen bonding were the main acting forces in the binding process. Molecular modeling result indicated that the hydrogen bonding played a major role in the binding of AEPI to ctDNA.

[Effects of DNMT1 Gene Silencing on Methylation of SOCS-1 Gene in Myeloma Cells].

OBJECTIVE: To investigate the effect of DNA methyhransferase l (DNMT1) gene silencing on methylation of suppressor of cytokine signaling (SOCS-1) in multiple myeloma RPMI 8226 cells. METHODS: Recombinant plasmid pshRNA-DNMTl was transfected into multiple myeloma RPMI 8226 cells by lipofectamine 2000. RT-PCR and Western blot were used to detect the mRNA and protein expression of DNMTl in RPMI 8226 cells respectively before and after transfection. Methylation-specific polymerase chain reaction was used to detect the methylation level change of SOCS-1 gene in RPMI8226 cells transfected. RESULTS: DNMTl targeted short hairpin RNA(shRNA) was successfully inserted into the plasmid vector pshRNA. RT-PCR results showed that the relative mRNA expression level of DNMTI gene in RPMI 8226 cells transfected with pshRNA was 0.176±0.004 which was significantly lower than that in cells transfected by empty vector (0.956±0.033, P<0.01). Western blot analysis showed that the relative expression level of DNMT1 protein of RPMI 8226 cells transfected by pshRNA was 0.065±0.014, which was significantly lower than that in transfected cells by empty vector(0.415±0.027) (P<0.05). These results indicated that the recombinant plasmid pshRNA could effectively knock down the expression of DNMT1 gene in RPMI 8226 cells. Methylation analysis showed that the methylation level of SOCS-1 gene was obviously reduced after transfection. CONCLUSION: DNMT1 gene in RPMI 8226 cell can be silenced by shRNA. DNMT1 gene silencing can significantly induce SOCS-1 gene hypomethylation, which indicates that DNMT1 may play an important role in the process of SOCS-1 hypermethylation.

Predicting time to emergency department return for anxiety disorders and acute stress reactions in children and adolescents: a cohort study.

PURPOSE: While studies indicate that few children with anxiety disorders receive specialized mental health care, significant knowledge gaps exist for the mental health care trajectory outside of specialized care. We examined whether physician-based care after an emergency department (ED) visit for mental health care predicted time to ED return. METHODS: We conducted a retrospective cohort study using administrative data from Alberta, Canada. Included in the cohort were 8075 children <18 years discharged from an ED (104 EDs in total), April 2002-September 2010, following a visit for an anxiety disorder or acute stress reaction. We used a multivariable Cox proportional hazards model to estimate time to ED return for mental health care (censored at 90 days). The variables of interest were: number and type of physician visits 30 days after index visit. We adjusted for sociodemographics, clinical acuity, comorbidity, and recent history of ED mental health care in the model. RESULTS: Within 30 days of ED discharge, multiple physician follow-up visits were associated with shorter return time (adjusted HR 1.24, 95 % CI 1.08-1.43). A single physician follow-up visit was associated with longer return time (adjusted HR 0.68, 95 % CI 0.58-0.79). Physician follow-up visits for mental health care were associated with shorter return time (adjusted HR 2.5, 95 % CI 2.21-2.83). CONCLUSIONS: Following an index visit, ED return by children with anxiety disorders or acute stress reactions is associated with specific characteristics of subsequent physician visits. Improving physician use of evidence-based treatment and family access to coordinated services may reduce costly hospital-based care.

Probing the interaction of anthraquinone with DNA by spectroscopy, molecular modeling and cancer cell imaging technique.

A new anthraquinone derivative, (E)-2-(1-(4,5-dihydroxy-6-(hydroxymethyl)-tetrahydro-2H-pyran-2-yloxyimino)ethyl)-1,4-dihydroxyanthracene-9,10-dione (AODGlc), was synthesized and its binding properties towards DNA were explored under physiological conditions by fluorescence spectroscopy, DNA melting as well as docking techniques. The experimental results revealed that AODGlc could bind to calf thymus DNA (ctDNA) through intercalation between DNA base pairs. The values of thermodynamic parameters at different temperatures including ΔG, ΔH, and ΔS and the molecular modeling study implied that hydrophobic interactions and hydrogen bonds were the main interactions in the AODGlc-ctDNA system. Cervical cancer cells (HepG2 cells) were used in cell viability assay and cell imaging experiment. AODGlc could interact with HepG2 cells and kill HepG2 cells under high concentration with nice curative effect, indicating its potential bioapplication in the future.

Knockdown of DNA methyltransferase-1 inhibits proliferation and derepresses tumor suppressor genes in myeloma cells.

DNA methyltransferases (including DNMT1, DNMT3A and DNMT3B), catalyze the transfer of methyl groups from S-adenosyl-l-methionine to cytosine position 5; this methylation in promoter regions silences gene expression. In addition, DNMT1 plays a critical role in the maintenance of genomic DNA methylation during DNA replication. In the present study, silencing of DNMT1 with siRNA was performed in RPMI-8226 human multiple myeloma (MM) cells, and the impact on gene methylation status and proliferation of the cells was analyzed. Upon DNMT1 downregulation, proliferation decreased significantly compared with that in the control, non-transfected cells. The expression of B-cell lymphoma 2 and nuclear factor κB proteins was also significantly reduced. Furthermore, nested methylation-specific polymerase chain reaction revealed that methylation of the tumor suppressor genes, suppressor of cytokine signaling 1 and p16, was significantly reduced upon DNMT1 knockdown. Our results suggest that DNMT1 silencing may be a promising strategy to consider during development of novel MM treatment strategies.