Effect of extracorporeal shockwave therapy for rotator cuff tendinopathy: a systematic review and meta-analysis.

BACKGROUND: Rotator cuff tendinopathy (RCT) is a widespread musculoskeletal disorder and a primary cause of shoulder pain and limited function. The resulting pain and limited functionality have a detrimental impact on the overall quality of life. The purpose of this study was to perform a systematic review of the effects of extracorporeal shock wave therapy (ESWT) for RCT. METHODS: The literature search was conducted on the following databases from inception to February 20, 2024: PubMed, Web of Science, the Cochrane Library, Scopus, MEDLINE, EMBASE, EBSCO, and China National Knowledge Infrastructure (CNKI) were checked to identify the potential studies exploring the effect of ESWT for the treatment of Rotator cuff tendinopathy (Calcification or non-calcification), control group for sham, other treatments (including placebo), without restriction of date, language. Two researchers independently screened literature, extracted data, evaluated the risk of bias in the included studies, and performed meta-analysis using RevMan 5.3 software. RESULTS: A total of 16 RCTs with 1093 patients were included. The results showed that compared with the control group, ESWT for pain score Visual Analogue Scale/Score (VAS) (SMD = -1.95, 95% CI -2.47, -1.41, P < 0.00001), function score Constant-Murley score (CMS) (SMD = 1.30, 95% CI 0.67, 1.92, P < 0.00001), University of California Los Angeles score (UCLA) (SMD = 2.69, 95% CI 1.64, 3.74, P < 0.00001), American Shoulder and Elbow Surgeons form (ASES) (SMD = 1.29, 95% CI 0.93, 1.65, P < 0.00001), Range of motion (ROM) External rotation (SMD = 1.00, 95% CI 0.29, 1.72, P = 0.02), Total effective rate (TER) (OR = 3.64, 95% CI 1.85, 7.14, P = 0.0002), the differences in the above results were statistically significant. But ROM-Abduction (SMD = 0.72, 95% CI -0.22, 1.66, P = 0.13), the difference was not statistically significant. CONCLUSION: Currently limited evidence suggests that, compared with the control group, ESWT can provide better pain relief, functional recovery, and maintenance of function in patients with RCT.

Highly Efficient Utilization of Ferrate(VI) Oxidation Capacity Initiated by Mn(II) for Contaminant Oxidation: Role of Manganese Species.

Manganese ion [Mn(II)] is a background constituent existing in natural waters. Herein, it was found that only 59% of bisphenol A (BPA), 47% of bisphenol F (BPF), 65% of acetaminophen (AAP), and 49% of 4-tert-butylphenol (4-tBP) were oxidized by 20 µM of Fe(VI), while 97% of BPA, 95% of BPF, 96% of AAP, and 94% of 4-tBP could be oxidized by the Fe(VI)/Mn(II) system [20 µM Fe(VI)/20 µM Mn(II)] at pH 7.0. Further investigations showed that bisphenol S (BPS) was highly reactive with reactive iron species (RFeS) but was sluggish with reactive manganese species (RMnS). By using BPS and methyl phenyl sulfoxide (PMSO) as the probe compounds, it was found that reactive iron species contributed primarily for BPA oxidation at low Mn(II)/Fe(VI) molar ratios (below 0.1), while reactive manganese species [Mn(VII)/Mn(III)] contributed increasingly for BPA oxidation with the elevation of the Mn(II)/Fe(VI) molar ratio (from 0.1 to 3.0). In the interaction of Mn(II) and Fe(VI), the transfer of oxidation capacity from Fe(VI) to Mn(III), including the formation of Mn(VII) and the inhibition of Fe(VI) self-decay, improved the amount of electron equivalents per Fe(VI) for BPA oxidation. UV-vis spectra and dominant transformation product analysis further revealed the evolution of iron and manganese species at different Mn(II)/Fe(VI) molar ratios.

Anthracite Releases Aromatic Carbons and Reacts with Chlorine to Form Disinfection Byproducts in Drinking Water Production.

Anthracite is globally used as a filter material for water purification. Herein, it was found that up to 15 disinfection byproducts (DBPs) were formed in the chlorination of anthracite-filtered pure water, while the levels of DBPs were below the detection limit in the chlorination of zeolite-, quartz sand-, and porcelain sandstone-filtered pure water. In new-anthracite-filtered water, the levels of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and ammonia nitrogen (NH3-N) ranged from 266.3 to 305.4 µg/L, 37 to 61 µg/L, and 8.6 to 17.1 µg/L, respectively. In aged anthracite (collected from a filter at a DWTP after one year of operation) filtered water, the levels of the above substances ranged from 475.1 to 597.5 µg/L, 62.1 to 125.6 µg/L, and 14 to 28.9 µg/L, respectively. Anthracite would release dissolved substances into filtered water, and aged anthracite releases more substances than new anthracite. The released organics were partly (around 5%) composed by the µg/L level of toxic and carcinogenic aromatic carbons including pyridine, paraxylene, benzene, naphthalene, and phenanthrene, while over 95% of the released organics could not be identified. Organic carbon may be torn off from the carbon skeleton structure of anthracite due to hydrodynamic force in the water filtration process.

Multidrug-resistant bacterial infection in adult patients following cardiac surgery: clinical characteristics and risk factors.

BACKGROUND: The prevalence of infections with multidrug-resistant organism (MDRO) pose great challenges for anti-infective therapy. Previous research on MDRO infections after cardiac surgery was limited. Therefore, understanding and mastering the clinical characteristics and risk predictors of MDRO infection after cardiac surgery is of great significance for standardized management of perioperative patients. METHODS: The medical records of adult patients with MDRO infection after cardiac surgery from January 2018 to October 2021 were collected, and patients were divided into MDR infection group (n = 176) and non-MDR infection group (n = 233). Univariate and multivariate regression analysis of variables was performed to determine the risk predictors of MDRO infection. RESULTS: The incidence of MDRO infection was 8.6%. Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa were the most common, accounting for 37.3%, 23.5% and 18.0%, respectively. The main infection type were lower respiratory tract infection (LTRI = 29.0%). Univariate analysis showed that underwent coronary artery bypass graft (CABG) (P = 0.001) and secondary operation (P = 0.008), pre-infection exposure to vancomycin (P < 0.001) and linezolid (P = 0.002), combination antibiotics (P < 0.001), four antibiotics in combination (P = 0.005), glucocorticoid use (P = 0.029), preoperative hypoalbuminemia (P = 0.003) were risk factors for post-operative MDRO infection. Multivariate regression analysis showed that underwent CABG (OR = 1.228, 95%CI = 1.056∽1.427, P = 0.008), secondary operation (OR = 1.910, 95%CI = 1.131∽3.425, P = 0.015) and pre-infection exposure to linezolid (OR = 3.704, 95%CI = 1.291∽10.629, P = 0.005) were independent risk predictors for MDRO infection. The risk of MDRO infection increased with the length of stay in the ICU (P < 0.001) and the length of stay before diagnosis of infection (P = 0.003), and the difference was statistically significant. Meanwhile, the length of stay after infection (P = 0.005) and the total length of hospital stay (P < 0.001) were significantly longer in the MDRO infection group, and the all-cause mortality was numerically higher in the MDRO infection group (31.3% versus 23.2%). CONCLUSIONS: The morbidity and mortality of MDRO infection was high in adult cardiac surgery, and many risk factors influence the occurrence of MDRO infection. In the future, clinicians should focus on high-risk patients, strengthen multidisciplinary collaboration on infection prevention and control measures, reduce the morbidity and mortality of MDRO infection, and improve the prognosis of in-hospital patients.

LARP7 alleviates psoriasis symptoms in mice by regulating the SIRT1/NF-κB signaling pathway.

OBJECTIVE: To unravel the role of La ribonucleoprotein 7 (LARP7), a transcriptional regulator, in the progression of psoriasis and the underlying molecular mechanisms. METHODS: The psoriasis-like mice model was created by daily administering of imiquimod on shaved skin. The histological analysis and skin damage were evaluated in each group. The inflammation and oxidative stress response were assessed by enzyme-linked-immunosorbent serologic and immunoblot assays. The involvement of silent information regulator 1 (member of the Sirtuin family; SIRT1/nuclear factor kappa B (NF-κB) signaling pathway in LARP7-mediated psoriasis progression was also detected by immunoblot assay. RESULTS: LARP7 relieved psoriasis symptoms in the mice model. LARP7 inhibited the expression of inflammatory cytokines as well as chemokines in psoriasis-like skin tissues. Additionally, LARP7 suppressed oxidative stress in the psoriasis-like skin tissues of mice. LARP7 inhibited the activation of the SIRT1/NF-κB signaling pathway, and therefore affected the progression of psoriasis. CONCLUSION: LARP7 relieved psoriasis symptoms in mice by regulating the SIRT1/NF-κB signaling pathway.

LARP7 upregulates SIRT1 deacetylase activity and inhibits Th1/Th17 cytokine response in psoriatic mice.

OBJECTIVE: To investigate the possible role of La ribonucleoprotein 7 (LARP7) in psoriasis through a mouse model and uncover its underlying mechanism. METHODS: The back skin of C57BL/6 mice was smeared with IMquimod (IMQ) cream for 7 days to induce psoriasis. Immunoblot kit was used to detect the deacetylase activity of SIRT1 (member of sirtuin family). Hematoxylin and eosin staining was used to assess the degree of psoriasis in mouse. Flow cytometry assays were performed to confirm effects on Th1/Th17 cell differentiation. Enzyme-linked-immunosorbent serologic assays were used to detect the level of secreted cytokines. RESULTS: LARP7 upregulated SIRT1 deacetylase activity. LARP7 alleviated psoriasis symptoms in mice by upregulating SIRT1 deacetylase activity. In addition, LARP7 regulated Th1/Th17 cell differentiation in psoriatic mice. We further found that LARP7 inhibited Th1/Th17 cytokine. CONCLUSION: LARP7 upregulated SIRT1 activity and inhibited Th1/Th17 cytokine response in psoriatic mice.

Long-Period Fiber Grating Sensors for Chemical and Biomedical Applications.

Optical fiber biosensors (OFBS) are being increasingly proposed due to their intrinsic advantages over conventional sensors, including their compactness, potential remote control and immunity to electromagnetic interference. This review systematically introduces the advances of OFBS based on long-period fiber gratings (LPFGs) for chemical and biomedical applications from the perspective of design and functionalization. The sensitivity of such a sensor can be enhanced by designing the device working at or near the dispersion turning point, or working around the mode transition, or their combination. In addition, several common functionalization methods are summarized in detail, such as the covalent immobilization of 3-aminopropyltriethoxysilane (APTES) silanization and graphene oxide (GO) functionalization, and the noncovalent immobilization of the layer-by-layer assembly method. Moreover, reflective LPFG-based sensors with different configurations have also been introduced. This work aims to provide a comprehensive understanding of LPFG-based biosensors and to suggest some future directions for exploration.

Microsecond-resolved smartphone time-gated luminescence spectroscopy.

Time-gated luminescence spectra are usually measured by laboratory instruments equipped with high-speed excitation sources and spectrometers, which are always bulky and expensive. To reduce the reliance on expensive laboratory instruments, we demonstrate the first, to the best of our knowledge, use of a smartphone for the detection of time-gated luminescence spectra. A mechanical chopper is used as the detection shutter and an optical switch is placed at the edge of the wheel to convert the chopping signal into a transistor-transistor logic (TTL) signal which is used to control the excitation source and achieve synchronization. The time-gated luminescence spectra at different delay times of Eu(TTA)3 powder and the solutions of Eu-tetracycline complex are successfully detected with a temporal resolution of tens of microseconds by the proposed approach. We believe our approach offers a route toward portable instruments for the measurement of luminescence spectra and lifetimes.

Occurrence of Iodophenols in Aquatic Environments and the Deiodination of Organic Iodine with Ferrate(VI).

Toxic and odorous iodophenols are commonly identified as disinfection by-products (DBPs) in drinking water. Herein, ng/L levels of iodophenols were identified in river water, wastewater treatment plant effluent, and medical wastewater, with the simultaneous identification of µg/L to mg/L levels of iodide (I-) and total organic iodine (TOI). Oxidation experiment suggested that the I-, TOI, and iodophenols could be oxidized by ferrate [Fe(VI)], and more than 97% of TOI had been transformed into stable and nontoxic IO3-. Fe(VI) initially cleaved the C-I bond of iodophenols and led to the deiodination of iodophenols. The resulted I- was swiftly oxidized into HOI and IO3-, with the intermediate phenolic products be further oxidized into lower molecular weight products. The Gibbs free energy change (ΔG) of the overall reaction was negative, indicating that the deiodination of iodophenols by Fe(VI) was spontaneous. In the disinfection of iodine-containing river water, ng/L levels of iodophenols and chloro-iodophenols formed in the reaction with NaClO/NH2Cl, while Fe(VI) preoxidation was effective for inhibiting the formation of iodinated DBPs. Fe(VI) exhibited multiple functions for oxidizing organic iodine, abating their acute toxicity/cytotoxicity and controlling the formation of iodinated DBPs for the treatment of iodide/organic iodine-containing waters.

Evaluating the role of subacromial impingement in rotator cuff tendinopathy: development and analysis of a novel rat model.

BACKGROUND: Subacromial impingement of the rotator cuff caused by variations in acromial anatomy or altered glenohumeral kinematics leads to inflammation and degeneration of the rotator cuff, ultimately contributing to the development of tendinopathy. However, the underlying cellular and molecular changes in the impinged tendon remain poorly understood. Because the rat is an accepted model for rotator cuff studies, we have developed a rat model to study rotator cuff tendinopathy. METHODS: Forty-four adult male Sprague-Dawley rats were allocated to one of 4 study groups: intact control group (group 1, n = 11); bilateral subacromial surgical clip placement to induce supraspinatus impingement for 2 weeks (group 2, n = 11), 4 weeks (group 3, n = 11), and 8 weeks (group 4, n = 11). Bilateral shoulder specimens were harvested for biomechanical testing, histology, and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. RESULTS: Radiography confirmed that all microvascular clips remained in stable position in the subacromial space. Gross inspection of supraspinatus tendon specimens in the impingement groups revealed changes in tendon morphology at the enthesis and midsubstance. Biomechanical evaluation demonstrated decreased supraspinatus tendon failure force and tissue stiffness at all time points compared with control tendons. Semiquantitative scoring of histologic specimens demonstrated significant, persistent tendinopathic changes over 8 weeks. qRT-PCR analysis of impinged tendon specimens demonstrated upregulation of gene expression for Col3 and Mmp14 in the impingement groups compared with control groups. In muscle samples, significant upregulation was seen in the expression of genes that are commonly associated with muscle atrophy (MuRF1 and Ube2b) and fatty infiltration (Fabp4, Pparg2, and Klf15). CONCLUSION: This new rat subacromial impingement model creates cellular and molecular changes consistent with the development of rotator cuff tendinopathy. The results of this study may serve as a baseline for future investigation.

Stability Analysis: Rational Design of a Ag Nanoparticle/Polymer Brush for Fabricating Cu Coating on a PET Surface.

Excellent stability of a catalytic center would facilitate the prolongation of the cycle of a chemical plating bath and the reduction of environmental pollution. In this study, silane (3-aminopropyltriethoxysilane (KH550) and γ-(2,3-epoxypropoxy)propytrimethoxysilane (KH560)) was incorporated in AgNO3 solution to rationally prepare a Ag nanoparticle/polymer brush (Ag/PB) catalytic solution. The effects of the KH560 relative content on the Ag/PB structure and stability were studied. The epoxy group in the KH560 could react with an amino group in the KH550 through direct ring-opening reaction to form a secondary amino group and hydroxyl, which could coadsorb Ag nanoparticles by means of a chelating structure; hence, Ag/PB with superior Ag-adsorbed intensity was established on a polyethylene terephthalate (PET) surface. Ag particles on PB with 75% KH560 revealed the best stability of those measured, and the relative Ag surplus was 56.7% after stability testing. The generated Ag/PB that served as catalytic centers to catalyze the electroless copper plating resulted in a facile technology for preparing Cu/PET composite material. This means that the technology has potential application in a green process for preparing metal/polymer composite materials.

Efficient Degradation of Organoarsenic by UV/Chlorine Treatment: Kinetics, Mechanism, Enhanced Arsenic Removal, and Cytotoxicity.

Roxarsone (ROX) has been widely used as an organoarsenic additive in animal feeding operations and poses a risk to the environment. Here, we first report the efficient degradation of ROX by UV/chlorine, where the kinetics, removal of total arsenic (As), and cytotoxicity were investigated. The kinetics study presented that reactive chlorine species (RCS) and HO• were the dominant species to react with ROX. Furthermore, the degradation rate of ROX can reach the maximum value at pH 7.5 due to the formation of more RCS. The degradation of ROX was affected by the amount of chlorine, pH, and water matrix. Through product analysis and Gauss theoretical calculation, two possible ROX degradation pathways were proposed. The free radicals attacked the As-C bond of ROX and resulted in releasing arsenate (As(V)). It was the reason that for an enhancement of the removal of total As by ferrous appeared after UV/chlorine, and over 98% of the total As was removed. In addition, cytotoxicity studies indicated that the cytotoxicity significantly enhanced during the degradation of ROX by UV/chlorine. However, by combination of UV/chlorine and adsorption, cytotoxicity can be greatly eliminated, probably due to the removal of As(V) and chlorinated products. These results further demonstrated that UV/chlorine treatment could be an effective method for the control of the potential environmental risks posed by organoarsenic.

Enhanced Radical Generation in an Ultraviolet/Chlorine System through the Addition of TiO2.

Ultraviolet (UV)/chlorine draws increasing attention for the abatement of recalcitrant organic pollutants. Herein, it was found that TiO2 would significantly promote the degradation of dimethyl phthalate (DMP) in the UV/chlorine system (from 19 to 84%). Hydroxyl radicals (HO•) and chlorine radicals (Cl•) were the dominant reactive species for DMP degradation in the UV/chlorine/TiO2 system. Chlorine decayed much faster in UV/chlorine/TiO2 compared with UV/chlorine, which is possibly because photogenerated electrons (ecb-) and superoxide radicals (O2•-) have high reactivity with chlorine. As a result, the recombination of photogenerated holes (hvb+) and ecb- was inhibited and the accumulation of HO• and Cl• was facilitated. A kinetic model was established to simulate the reaction process, and it was found that the concentrations of HO• and Cl• were several times to dozens of times higher in UV/chlorine/TiO2 than that in UV/chlorine. The contributions of HO• and Cl• to DMP degradation were 70.3 and 29.7% by model simulation, respectively, and were close to the probe experiment result. In the UV/chlorine/TiO2 system, the degradation of DMP did not follow pseudo-first-order kinetics but the degradation of benzoate fitted well with pseudo-first-order kinetics. This phenomenon was elucidated by the structure of the pollutant and TiO2 and further tested by calculating the adsorption energy (Eads)/binding energy (Eb) with density functional theory. Due to faster decay of chlorine, lower amounts of disinfection byproducts formed in UV/chlorine/TiO2 compared with UV/chlorine. Adding TiO2 into the UV/chlorine system can promote the degradation of recalcitrant organic pollutants in an aqueous environment.

Association between premature ovarian insufficiency and gut microbiota.

BACKGROUND: Premature ovarian insufficiency (POI) is characterized by impairment of ovarian function on a continuum before the age of 40 years. POI is affected by multiple factors. Considering new insights from recent gut microbiome studies, this study aimed to investigate the relationship between gut microbial community structure and POI. METHODS: Subjects were recruited at the Shenzhen Maternity & Child Healthcare Hospital. Fecal microbial community profiles of healthy women (n = 18), women with POI (n = 35) were analyzed using 16S rRNA gene sequencing based on Illumina NovaSeq platform. RESULTS: Compared to the controls, the serum levels of FSH, LH, T and FSH/LH ratio significantly increased in women with POI, whereas E2 and AMH decreased significantly. Higher weighted UniFrac value was observed in POI women compared with healthy women. Phylum Firmicutes, genera Bulleidia and Faecalibacterium were more abundant in healthy women, while phylum Bacteroidetes, genera Butyricimonas, Dorea, Lachnobacterium and Sutterella enriched significantly in women with POI. Moreover, these alterations of the gut microbiome in women with POI were closely related to FSH, LH, E2, AMH level and FSH/LH ratio. CONCLUSIONS: Women with POI had altered microbial profiles in their gut microbiome, which were associated with serum hormones levels. These results will shed a new light on the pathogenesis and treatment for POI.

Ferrate Oxidation of Phenolic Compounds in Iodine-Containing Water: Control of Iodinated Aromatic Products.

Highly toxic iodinated products would form in oxidation and disinfection of iodine-containing water. Variation of iodinated aromatic products in ferrate [Fe(VI)] oxidation of phenolic compounds (phenol, bisphenol A (BPA), and p-hydroxybenzoic acid (p-HBA)) in iodine-containing water was investigated. At pH 5.0, oxidation of phenolic compounds was inhibited by competitive reaction of ferrate with I-, and no formation of iodinated aromatic products was detected. Almost all I- was converted into nontoxic IO3-. At pH 7.0, 8.0, and 9.0, HOI formed in ferrate oxidation of I- and further reacted with phenols, with the formation of iodinated aromatic products. Mass spectrometry analysis showed that both kinds and contents of iodinated aromatic products were raised with the increase in solution pH and the content of I-, and these iodinated aromatic products were further oxidized by ferrate. Ferrate deprived iodine from iodinated aromatic products and transferred highly toxic organic iodine into nontoxic IO3-. An electron-donating substituent (alkyl) increased the reactivity of phenol with ferrate and HOI and facilitated ferrate oxidation of iodinated phenols. An electron-drawing substituent (carboxyl) decreased the reactivity of phenol with ferrate and HOI and hindered the further oxidation of iodinated aromatic products. A kinetic model about the variation of phenol, BPA, and p-HBA in reaction with ferrate in iodine-containing water was developed, and the oxidation profile of phenolic compounds could be satisfactorily predicted at various iodide concentrations.

Enhanced Permanganate Oxidation of Sulfamethoxazole and Removal of Dissolved Organics with Biochar: Formation of Highly Oxidative Manganese Intermediate Species and in Situ Activation of Biochar.

Sulfamethoxazole (SMX) is a broad-spectrum antibiotic and was largely used in breeding industry. The reaction rate of SMX with KMnO4 is slow, and the adsorption efficiency of biochar for SMX was inferior (less than 11% in 30 min). By adding biochar powder into SMX solution with the addition of permanganate, the oxidation ratio of SMX surged to 97% in 30 min, and over 58% of the total organic carbon (TOC) was simultaneously removed. KMnO4 interacted with biochar and resulted in the formation of highly oxidative intermediate manganese species, which transformed SMX into hydrolysis products, oxygen-transfer products, and self-coupling products. Brunauer-Emmett-Teller (BET) analysis showed that surface area, total pore volume, and micropore volume of biochar increased by 32.1%, 36.4%, and 80.6%, respectively, after reaction process. This in situ activation of biochar with KMnO4 enhanced its adsorption capacity and led to great improvement of TOC removal. Besides KMnO4 oxidation, biochar also enhanced TOC removal in Mn(III) oxidation (KMnO4+ bisulfite) and ozonization of SMX. Considering that KMnO4 could react with biochar and result in the formation of intermediate manganese species, while biochar can be simultaneously activated and exhibit high capacity for organic adsorption, the combination of biochar with the chemical/advanced oxidation could be a promising process for the removal of environmental pollutants.

Removal of Organoarsenic with Ferrate and Ferrate Resultant Nanoparticles: Oxidation and Adsorption.

Many investigations focused on the capacity of ferrate for the oxidation of organic pollutant or adsorption of hazardous species, while little attention has been paid on the effect of ferrate resultant nanoparticles for the removal of organics. Removing organics could improve microbiological stability of treated water and control the formation of disinfection byproducts in following treatment procedures. Herein, we studied ferrate oxidation of p-arsanilic acid ( p-ASA), an extensively used organoarsenic feed additive. p-ASA was oxidized into As(V), p-aminophenol ( p-AP), and nitarsone in the reaction process. The released As(V) could be eliminated by in situ formed ferric (oxyhydr) oxides through surface adsorption, while p-AP can be further oxidized into 4,4'-(diazene-1,2-diyl) diphenol, p-nitrophenol, and NO3-. Nitarsone is resistant to ferrate oxidation, but mostly adsorbed (>85%) by ferrate resultant ferric (oxyhydr) oxides. Ferrate oxidation (ferrate/ p-ASA = 20:1) eliminated 18% of total organic carbon (TOC), while ferrate resultant particles removed 40% of TOC in the system. TOC removal efficiency is 1.6 to 38 times higher in ferrate treatment group than those in O3, HClO, and permanganate treatment groups. Besides ferrate oxidation, adsorption of organic pollutants with ferrate resultant nanoparticles could also be an effective method for water treatment and environmental remediation.

Impact of Phosphate on Ferrate Oxidation of Organic Compounds: An Underestimated Oxidant.

Ferrate (K2FeO4) is a powerful oxidant and up to 3 mol of electrons could be captured by 1 mol of ferrate in the theoretical conversion of Fe(VI)-Fe(V)-Fe(IV)-Fe(III). However, it is reported that the utilization efficiency of the ferrate oxidation capacity is quite low because of the rapid autodecomposition of intermediate iron species, which negatively influences the potential of ferrate on organic pollutants control. We accidentally found that for the ferrate oxidation of carbamazepine (CBZ), bisphenol S (BPS), diclofenac (DCF), and ciprofloxacin (CIP), the determined reaction rate constants were 1.7-2.4 times lower in phosphate buffer than those in borate buffer at pH 8.0. For the reaction of ferrate with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) at pH 7.0, the determined reaction stoichiometries were 1:1.04 in 100 mM phosphate buffer, 1:1.18 in 10 mM phosphate buffer, and 1:1.93 in 10 mM borate buffer, respectively. The oxidation ability of ferrate seems depressed in phosphate buffer. A kinetic model involving the oxidation of ABTS by Fe(VI), Fe(V) and Fe(IV) species was developed and fitted the ABTS•+ formation kinetics well under different buffer conditions. The results showed that phosphate exhibited little influence on the oxidation ability of Fe(VI) and Fe(IV) species, but decreased the specific rate constants of ABTS with Fe(V) species by 1-2 orders of magnitude, resulting in the outcompeting of Fe(V) autodecomposition pathway. The complexation between phosphate anions and Fe(V) species may account for the inhibition effect of phosphate buffer. Considering that many studies regarding ferrate oxidation were carried out in phosphate buffer, the actual oxidation ability of ferrate may be underestimated.

Theoretical investigation of photonic generation of frequency quadrupling linearly chirped waveform with large tunable range.

To generate linearly chirped microwave signals with a large frequency tunable range, a photonic approach is proposed. Firstly, A dual-output dual-parallel Mach-Zehnder modulator (DPMZM) followed by the polarization beam combiner and an optical filter is utilized to generate orthogonally polarized ± second-order optical sidebands. Then a polarization modulator is employed to achieve the phase modulation of the two wavelengths. Finally, the balanced detection is applied to suppress the distortion and background noise. The key advantages of the proposed scheme are the central frequency multiplying operation and large frequency tunable range. Simulation results show that a linearly chirped pulse product with time-bandwidth as well as a compression ratio for the pulse of 11 and 9.3 respectively, and a peak-to-sidelobe ratio (PSR) of 7.4 dB is generated. The system has both good reconfigurability and tunability, its frequency can be continuously adjusted from about 10 GHz to as much as 50 GHz in principle.