Airway and Voice Outcomes After Thyroarytenoid Myomectomy for Bilateral Vocal Fold Immobility.

INTRODUCTION: Type 4 posterior glottic stenosis and bilateral vocal fold paralysis are clinically challenging causes of bilateral vocal fold immobility (BVFI) that result in glottic airway obstruction. Established procedures for BVFI typically worsen dysphonia. We hypothesize the use of thyroarytenoid myomectomy (TAM) in the setting of BVFI will improve dyspnea with decreased detriment to voice. METHODS: Eleven unilateral TAM procedures were performed between April 2021 and June 2023 at a single institution. Pre- and postoperative patient reported outcomes were compared. Representative images of maximal glottic opening were analyzed in ImageJ to calculate ipsilateral bowing index (BI), total BI, maximum glottic surface area (MGSA), and maximum opening angle (MOA). Statistical comparisons were performed with paired t-tests when normality was confirmed with Shapiro-Wilk test and otherwise with Wilcoxon signed-rank tests, with threshold for significance of α = 0.05. Interrater reliability for objective glottal measures was compared with intraclass correlation coefficient (ICC). RESULTS: Dyspnea Index improved from mean (standard error) of 24.1 (3.8) to 9.1 (3.3), p = 0.004. Voice Handicap Index-10 improved from 20.0 (4) to 10.3 (3.8), p = 0.011. Glottal Function Index improved from 9.6 (1.4) to 6.3 (1.3), p = 0.017. There was no significant difference in ipsilateral BI, total BI, MOA, and median MGSA. There was good to excellent ICCs for all comparisons (0.83-0.95). CONCLUSIONS: TAM demonstrated significant improvement in symptoms from BVFI while not significantly altering glottal structure. These data suggest TAM improves dyspnea in patients with BVFI without significantly impairing voice. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Non-negligible impact of microplastics on wetland ecosystems.

There has been much concern about microplastic (MP) pollution in marine and soil environments, but attention is gradually shifting towards wetland ecosystems, which are a transitional zone between aquatic and terrestrial ecosystems. This paper comprehensively reviews the sources of MPs in wetland ecosystems, as well as their occurrence characteristics, factors influencing their migration, and their effects on animals, plants, microorganisms, and greenhouse gas (GHG) emissions. It was found that MPs in wetland ecosystems originate mainly from anthropogenic sources (sewage discharge, and agricultural and industrial production) and natural sources (rainfall-runoff, atmospheric deposition, and tidal effects). The most common types and forms of MPs identified in the literature were polyethylene and polypropylene, fibers, and fragments. The migration of MPs in wetlands is influenced by both non-biological factors (the physicochemical properties of MPs, sediment characteristics, and hydrodynamic conditions) and biological factors (the adsorption and growth interception by plant roots, ingestion, and animal excretion). Furthermore, once MPs enter wetland ecosystems, they can impact the resident microorganisms, animals, and plants. They also have a role in global warming because MPs act as unique exogenous carbon sources, and can also influence GHG emissions in wetland ecosystems by affecting the microbial community structure in wetland sediments and abundance of genes associated with GHG emissions. However, further investigation is needed into the influence of MP type, size, and concentration on the GHG emissions in wetlands and the underlying mechanisms. Overall, the accumulation of MPs in wetland ecosystems can have far-reaching consequences for the local ecosystem, human health, and global climate regulation. Understanding the effects of MPs on wetland ecosystems is essential for developing effective management and mitigation strategies to safeguard these valuable and vulnerable environments.

Indications and Short-Term Outcomes for In-Office Therapeutic Superior Laryngeal Nerve Block.

OBJECTIVE: Superior laryngeal nerve (SLN) block consists of injection of steroid and anesthetic at the internal branch of the SLN entry site. Prior case series have demonstrated beneficial effects on neurogenic cough. SLN blocks have also recently shown benefit for paralaryngeal pain. We describe short-term outcomes for multiple symptoms of irritable larynx syndrome (ILS) including neurogenic cough, dysphonia related to laryngeal hypersensitivity, inducible laryngeal obstruction (ILO), paralaryngeal pain, and isolated globus. METHODS: Retrospective review from 2 institutions of patients undergoing a single SLN block for the indications listed. Variables include age, sex, indication(s), known vagus neuropathy, and patient-reported outcomes at short-term follow-up. RESULTS: A total of 209 patients were included (59 males, 150 females; age: 58 ± 13 years). Twenty-six patients (12%) had a history of a vagus nerve injury. Indications included neurogenic cough (n = 149), dysphonia related to laryngeal hypersensitivity (n = 66), paralaryngeal pain (n = 50), ILO (n = 23), and isolated globus (n = 3). Some patients had multiple indications. Significant improvements in patient-reported measures occurred after a single SLN block within 2 to 4 weeks for neurogenic cough (cough severity index; 25.2 ± 11.2 to 19.0 ± 12.8; P < .001), dysphonia (voice handicap index-10; 22.1 ± 12.2-18.0 ± 13.3; P = .005), and ILO (dyspnea index; 21.0 ± 14.9-14.7 ± 15.7; P = .017). Subjective pain improved in 23 of 39 patients with paralaryngeal pain. There was no observed improvement for isolated globus. Presence of known vagal neuropathy or therapy around the time of SLN block did not affect outcome. CONCLUSION: SLN block can be an effective component of treatment for a variety of ILS symptoms. Patients may experience some improvement after 1 injection. LAY SUMMARY: Symptoms of irritable larynx syndrome, such as neurogenic cough, paralaryngeal pain, inducible laryngeal obstruction, and dysphonia related to laryngeal hypersensitivity can be challenging to manage. In-office Superior Laryngeal Nerve blocks can serve as a quick, well tolerated, adjunctive treatment with positive short-term outcomes. LEVEL OF EVIDENCE: 4.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange in Endoscopic Esophageal Surgery.

OBJECTIVES: Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) describes apneic oxygenation using humidified high flow nasal-cannula oxygen. Although it has been described as a sole mode of oxygenation in endoscopic laryngotracheal surgery, its use in endoscopic esophageal surgery under general anesthesia with neuromuscular paralysis has not previously been described. The objective of this study is to assess the safety and efficacy of THRIVE in esophagology. METHODS: We conducted a retrospective review of adult patients undergoing esophageal procedures under general anesthesia who were oxygenated using THRIVE at two academic institutions. Demographic, clinical, and anesthesiologic data were collected and analyzed. RESULTS: 14 cases performed from March 2021 to March 2022 met inclusion criteria. 13/14 (92.9%) of patients were able to maintain oxygenation throughout the entirety of their procedure. The mean apneic time was 17.9 minutes with a maximum of 32 minutes. One patient required "rescue" intubation due to failure to maintain oxygenation. Excluding the sole THRIVE failure, the median SpO2 at the conclusion of surgery was 99% (range 94-100%). A linear regression model yielded an increase in EtCO2 of 0.95 mmHg/min or 0.127 kPa/min. SpO2 was negatively associated with both tobacco pack-year smoking history (R2 = 0.343, P = .014) and BMI (R2 = 0.238, P = .038). CONCLUSION: THRIVE is a feasible, safe, and efficacious means of apneic oxygenation for patients undergoing esophageal endoscopic surgery under general anesthesia with neuromuscular paralysis, which may be particularly beneficial in patients with airway stenosis, as post-intubation changes can have severe clinical implications for this patient population. Obese patients and tobacco smokers may be at increased risk of oxygen desaturation when using THRIVE.

Novelty three stages for humification of sewage sludge during hyperthermophilic aerobic fermentation.

Compared with conventional aerobic fermentation (CAF), there is limited knowledge of how hyperthermophilic aerobic fermentation (HAF) enhances the humification of sewage sludge. This study compared three novel stages of organic degradation, precursors, functional groups, bacterial community, and humus synthesis mechanism in HAF with CAF. The results showed that organic matter (OM) degraded rapidly, and 68% of the degradation could be completed of stage I in HAF. Compared with the initial stage, ammonium nitrogen (NH4+-N), water-soluble organic carbon, and water-soluble total nitrogen increased by 2.83 times, 40.5 times, and 33.5 times, respectively. Cellulose and hemicellulose decreased by 29.22% and 21.85%, respectively. These results suggested that temperature (>80 °C) and Bacillus dominated accelerate the humification process by rapidly improving OM degradation. Compared with the initial value of HAF, the maximum increment of reducing sugar at stage II was 297%, and the degradation rate of cellulose was effectively increased by 21.03% compared with that of CAF. The precursors such as reducing sugars and amino acids formed humus at stage II. The content of Aryl C increased significantly during the HAF process, the degree of polymerization of humus and the aromatization degree of HA and FA increased significantly, and complex organic macromolecular material polymers were formed at stage III. The sugar-amine condensation was the mechanism of humification in the sludge HAF process. This investigation provided three new stages of insights into the synthesis of humification during the HAF process and extended the current mechanism of humification in the HAF process.

The spatial effects of rural toilet retrofitting investment on farmers' medical and health expenditure in China.

Background: China stretches across a vast area, and different geographical environments and economic and social development conditions, along with learning imitation and factor flow among participants can lead to two major spatial characteristics of toilet retrofitting investment: spatial heterogeneity and spatial correlation. Methods: This study contributes to explore this topic by assessing the spatial heterogeneity and spatial correlation of toilet retrofitting investment on farmers' medical and health expenditure based on the spatial econometric model. Results: (1) There are significant spatial agglomeration characteristics of both the toilet retrofitting investment and farmers' medical and health expenditure in China. (2) At the national level, the rural toilet retrofitting investment will influence the farmers' medical and health expenditure, and the effect on the local area is greater than on the surrounding areas. (3) After taking into account the differences in natural geographical environment and social and economic development, China is divided into four regions: east, central, west and northeast. In terms of spatial effects within different regions, the intensity of the impact of toilet retrofitting investment on local farmers' medical and health expenditure is in the order of central > eastern > western > northeast. The improvement of people's livelihood in the eastern and central regions by toilet retrofitting investment would lead to imitation by surrounding regions, thus reflecting spillover effects, while in the western region, toilet retrofitting investment would trigger fierce competition in related industries and factor markets, manifesting the competition effect. (4) As for the spatial effects across different regions, the toilet retrofitting investment produces spillover effects in all four regions, among which the intensity of the influence effect is the greatest in the central-western region, followed by the west-northeast, and the influence effect in the east-west is not significant. Discussion: The comprehensive promotion of rural toilet retrofitting should not only focus on investment in the western and northeastern regions, but also strengthen regional communication and cooperation to improve rural residents' health and quality of life.

Implementation of an interdisciplinary tracheostomy care protocol to decrease rates of tracheostomy-related pressure ulcers and injuries.

OBJECTIVES: Tracheostomy-related pressure injuries (TRPI) have been demonstrated to occur in approximately 10% of tracheostomy patients. In this study, we present TRPI outcomes after implementation of a standardized tracheostomy care protocol. METHODS: A tracheostomy care protocol was developed by an interdisciplinary quality improvement program and implemented on July 1, 2016. The protocol was designed to minimize factors that contribute to the development of TRPI. Rates of TRPI over the subsequent 20 months were compared to the year before implementation. RESULTS: 9 out of 85 patients (10.6%) developed TRPI in the pre-protocol cohort compared to 0 of 137 (0%) in the post-protocol cohort, which was a statistically significant decrease by Fisher's exact test with a p-value of 0.0001. Pearson's correlation coefficient demonstrated a negative correlation between age and post-operative day of diagnosis (r = -0.641, p = 0.063), indicating that older patients develop TRPI more quickly. CONCLUSIONS: Interdisciplinary peri-operative tracheostomy care protocols can be effective in decreasing rates of TRPI.

Iguratimod ameliorates inflammatory responses by modulating the Th17/Treg paradigm in dextran sulphate sodium-induced murine colitis.

Inflammatory bowel disease (IBD) is an autoimmune disease with an abnormal and persistent immune response. Iguratimod, a novel anti-rheumatic drug, exhibits anti-inflammatory effects and regulates immune response. The role of iguratimod in intestinal mucosal inflammation and immunity has not been examined. The aim of this study was to investigate whether iguratimod ameliorates dextran sulphate sodium (DSS)-induced murine colitis and its potential regulatory mechanism. Murine colitis was induced by administering 2.5% DSS for 5days. Some mice were administered iguratimod (5, 30mg/kg) by oral gavage once daily for 7days, beginning on the day 3 after colitis induction. Our study showed that iguratimod alleviates the symptoms of colitis and suppresses intestinal tissue damage, including macroscopic and histopathological manifestations. Moreover, iguratimod reduced interleukin (IL)-6, IL-17, and tumour necrosis factor-α levels, and increased the expression levels of IL-10 and TGF-ß. In addition, iguratimod downregulated the proportion of Th17 cells, the level of transcription factor retinoic acid-related orphan receptor γt (RORγt), and the phosphorylation of signal transducer and activator of transcription-3 (STAT3), and upregulated the proportion of Treg cells, the level of transcription factor forkhead box p3 (Foxp3), and the phosphorylation of STAT5 in the colonic tissues. In conclusion, iguratimod plays a protective role in mice with DSS-induced colitis via anti-inflammatory effects and regulation of Th17/Treg cells. Therefore, use of iguratimod may serve as a novel therapeutic strategy for the treatment of IBD.

Comparison of Survival Outcomes Following Postsurgical Radioactive Iodine Versus External Beam Radiation in Stage IV Differentiated Thyroid Carcinoma.

BACKGROUND: There is a lack of well-powered data regarding outcomes in stage IV differentiated thyroid carcinoma (DTC) treated with postsurgical radiation. The objective of this study was to examine survival in patients with stage IV papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) who received radioactive iodine (RAI), external beam radiation therapy (EBRT), or neither following surgery. METHODS: In this retrospective cohort study, data collected from the National Cancer Data Base (NCDB) yielded 11,832 patients with stage IV DTC who underwent primary surgical treatment between 2002 and 2012. Patients were stratified by histology and sub-stage. Fully parametric, multilevel survival-time models were used to evaluate survival outcomes in three adjuvant treatment groups: RAI, EBRT, or no adjuvant radiation. Hazard ratios (HR) and time ratios (TR) were calculated against patients who did not receive radiation. All models were adjusted for demographic and clinical factors. RESULTS: The mean age of all patients was 61.6 years (SD = 11.6), and 57.5% were female. Patients who received EBRT had significantly higher 5- and 10-year hazards of death in several PTC sub-stages (10-year HRPTC Stage IV-A = 2.12 [confidence interval (CI) 1.79-2.52]; HRPTC Stage IV-B = 2.03 [CI 1.33-3.10]). For stage IV-B PTC requiring EBRT, lifespan after diagnosis was shortened by a factor of 3 when compared to patients who did not receive radiation (TRPTC Stage IV-B = 0.32 [CI 0.16-0.62]). In contrast, RAI was significantly associated with improved 5- and 10-year survival in both PTC and FTC patients regardless of pathological sub-stage. Large reductions in mortality were observed in patients with FTC who were treated with RAI (HRFTC Stage IV-C = 0.19 [CI 0.06-0.65]). When patients with stage IV-C FTC were treated with RAI, life-span after diagnosis doubled (TRFTC Stage IV-C = 1.98 [CI 1.31-3.00]). CONCLUSIONS: Through the NCDB, this study sought to describe prognosis and survival for adjuvant radiation in stage IV DTC. RAI was associated with improved survival for stage IV DTC. Despite treatment benefits conferred by adjuvant EBRT, indications to treat with EBRT were associated with poorer survival outcomes in patients with advanced-stage DTC, particularly PTC.

Safety and outcomes of cochlear implantation in the elderly: A review of recent literature.

Global demographic changes related to longevity are leading to increasing numbers of the elderly, for whom hearing loss is a significant cause of morbidity and disability. Once met with reticence, severely hearing impaired older adults are increasingly being considered for cochlear implantation (CI). Significant data indicate that CI in the elderly population is safe, well-tolerated, and effective. Risks from CI surgery and anesthesia are low and generally comparable to rates in other age groups. Outcomes studies regarding CI in older adults have shown excellent improvements to speech perception, quality of life, and even cognition. Overall, currently available data suggests that advanced age should not, in itself, be considered a barrier to implantation. This review paper will highlight selected articles from recent medical literature regarding the safety and efficacy of CI in the elderly population.

High Incidence of Malaria Along the Sino-Burmese Border Is Associated With Polymorphisms of CR1, IL-1A, IL-4R, IL-4, NOS, and TNF, But Not With G6PD Deficiency.

Malaria is highly endemic in Yunnan Province, China, with the incidence of malaria being highest along the Sino-Burmese border. The aim of our study was to determine whether genetic polymorphisms are associated with the prevalence of malaria among Chinese residents of the Sino-Burmese border region. Fourteen otherwise healthy people with glucose-6-phosphate dehydrogenase (G6PD) deficiency, 50 malaria patients, and 67 healthy control subjects were included in our cross-sectional study. We analyzed the frequency of the G3093T and T520C single-nucleotide polymorphisms (SNPs) of CR1. Logistic regression was used to calculate the prevalence odds ratio (POR) and 95% confidence interval (CI) of malaria for the T520C SNP of CR1 and SNPs of G6PD, IL-4, IL-4R, IL-1A, NOS, CD40LG, TNF, and LUC7L. The frequency of the 3093T/3093T genotype of CR1 in the malaria group (0.16) was significantly higher than that in the control group (0.045, P < 0.05), and significantly lower than that in the G6PD deficiency group (0.43, P < 0.01). The frequency of the 520T/520T genotype of CR1 was significantly higher in the malaria patients (0.78) than that in the control group (0.67, P < 0.05) and G6PD-deficiency group (0.36, P < 0.05). The T allele of the T520C variant of CR1 was significantly associated with the prevalence of malaria (POR: 1.460; 95% CI: 0.703-3.034). Polymorphisms of G6PD did not significantly influence the prevalence malaria (P > 0.05). A GTGTGTC haplotype consisting of IL-1A (rs17561), IL-4 (rs2243250), TNF (rs1800750), IL-4R (rs1805015), NOS (rs8078340), CD40LG (rs1126535), and LUC7L (rs1211375) was significantly associated with the prevalence of malaria (POR: 1.822, 95% CI: 0.998-3.324). The 3093G/3093G and 520T/520T genotypes are the predominant genetic variants of CR1 among Chinese residents near the Sino-Burmese border, and the T allele of T520C is associated with the prevalence of malaria in this region. Although G6PD deficiency does not protect against malaria, it may diminish the association between malaria and the CR1 polymorphisms in this population. The GTGTGTC haplotype is also associated with the prevalence of malaria in this region.

Patients undergoing total laryngectomy: an at-risk population for 30-day unplanned readmission.

IMPORTANCE: Patients undergoing total laryngectomy are at high risk for hospital readmission. Hospital readmissions are increasingly scrutinized because they are used as a metric of quality care and are subject to financial penalties. OBJECTIVE: To determine the rate of, reasons for, and risk factors that predict 30-day unplanned readmission for patients undergoing total laryngectomy. DESIGN, SETTING, AND PATIENTS: Retrospective cohort study at a single academic tertiary referral medical center. The study population comprised 155 patients who underwent total laryngectomy with or without flap closure between January 2007 and December 2012 as either a primary treatment or salvage treatment for prior nonsurgical management. INTERVENTIONS: Total laryngectomy. MAIN OUTCOMES AND MEASURES: Rate of 30-day unplanned readmission, readmission diagnoses, and risk factors for unplanned readmission. Univariable and multivariable logistic regression were performed to identify risk factors for unplanned readmission within 30 days of discharge. RESULTS: The 30-day unplanned readmission rate for patients following discharge after total laryngectomy was 26.5% (41 of 155). The most common readmission diagnoses were pharyngocutaneous fistula (27% of readmissions; n = 11) and stomal cellulitis (16% of readmissions; n = 7). The median time to unplanned readmission was 7 days. Thirty-four percent of readmissions (14 of 41) occurred within 3 days of discharge. Significant predictors of 30-day unplanned readmission on multivariable analysis were postoperative complication after discharge (odds ratio [OR], 11.50; 95% CI, 4.10-32.28), visit to the emergency department within 30 days after discharge (OR, 5.25; 95% CI, 1.84-14.99), salvage total laryngectomy (OR, 3.52; 95% CI, 1.56-13.12), and chyle fistula during the index hospitalization (OR, 5.25; 95% CI, 0.86-29.92). The discriminative ability of the model to predict unplanned readmission, as measured by the C statistic, was 0.88. CONCLUSIONS AND RELEVANCE: Patients undergoing total laryngectomy are an at-risk patient population with a high rate of unplanned readmission within 30 days of discharge. By identifying the risk factors that predict 30-day unplanned readmission, these data can be used to design and implement quality-improvement interventions to decrease readmissions.

Dynamics of autotrophic marine planktonic thaumarchaeota in the East China Sea.

The ubiquitous and abundant distribution of ammonia-oxidizing Thaumarchaeota in marine environments is now well documented, and their crucial role in the global nitrogen cycle has been highlighted. However, the potential contribution of Thaumarchaeota in the carbon cycle remains poorly understood. Here we present for the first time a seasonal investigation on the shelf region (bathymetry≤200 m) of the East China Sea (ECS) involving analysis of both thaumarchaeal 16S rRNA and autotrophy-related genes (acetyl-CoA carboxylase gene, accA). Quantitative PCR results clearly showed a higher abundance of thaumarchaeal 16S and accA genes in late-autumn (November) than summer (August), whereas the diversity and community structure of autotrophic Thaumarchaeota showed no statistically significant difference between different seasons as revealed by thaumarchaeal accA gene clone libraries. Phylogenetic analysis indicated that shallow ecotypes dominated the autotrophic Thaumarchaeota in the ECS shelf (86.3% of total sequences), while a novel non-marine thaumarchaeal accA lineage was identified in the Changjiang estuary in summer (when freshwater plumes become larger) but not in autumn, implying that Changjiang freshwater discharge played a certain role in transporting terrestrial microorganisms to the ECS. Multivariate statistical analysis indicated that the biogeography of the autotrophic Thaumarchaeota in the shelf water of the ECS was influenced by complex hydrographic conditions. However, an in silico comparative analysis suggested that the diversity and abundance of the autotrophic Thaumarchaeota might be biased by the 'universal' thaumarchaeal accA gene primers Cren529F/Cren981R since this primer set is likely to miss some members within particular phylogenetic groups. Collectively, this study improved our understanding of the biogeographic patterns of the autotrophic Thaumarchaeota in temperate coastal waters, and suggested that new accA primers with improved coverage and sensitivity across phylogenetic groups are needed to gain a more thorough understanding of the role of the autotrophic Thaumarchaeota in the global carbon cycle.

Niche partitioning of marine group I Crenarchaeota in the euphotic and upper mesopelagic zones of the East China Sea.

Marine group I Crenarchaeota (MGI) represents a ubiquitous and numerically predominant microbial population in marine environments. An understanding of the spatial dynamics of MGI and its controlling mechanisms is essential for an understanding of the role of MGI in energy and element cycling in the ocean. In the present study, we investigated the diversity and abundance of MGI in the East China Sea (ECS) by analysis of crenarchaeal 16S rRNA gene, the ammonia monooxygenase gene amoA, and the biotin carboxylase gene accA. Quantitative PCR analyses revealed that these genes were higher in abundance in the mesopelagic than in the euphotic zone. In addition, the crenarchaeal amoA gene was positively correlated with the copy number of the MGI 16S rRNA gene, suggesting that most of the MGI in the ECS are nitrifiers. Furthermore, the ratios of crenarchaeal accA to amoA or to MGI 16S rRNA genes increased from the euphotic to the mesopelagic zone, suggesting that the role of MGI in carbon cycling may change from the epipelagic to the mesopelagic zones. Denaturing gradient gel electrophoretic profiling of the 16S rRNA genes revealed depth partitioning in MGI community structures. Clone libraries of the crenarchaeal amoA and accA genes showed both "shallow" and "deep" groups, and their relative abundances varied in the water column. Ecotype simulation analysis revealed that MGI in the upper ocean could diverge into special ecotypes associated with depth to adapt to the light gradient across the water column. Overall, our results showed niche partitioning of the MGI population and suggested a shift in their ecological functions between the euphotic and mesopelagic zones of the ECS.

The application of complex multiple forklike ZnO nanostructures to rapid and ultrahigh sensitive hydrogen peroxide biosensors.

A new complex multiple forklike ZnO nanostructure was fabricated by citric acid assisted annealing process. The complex multiple forklike ZnO nanostructure is composed of several nanorods. These nanorods grow from a thin platelet base and are parallel to each other to form complex multiple forklike ZnO nanostructure. The widthes of thin platelet bases range from 60 to 230 nm. The diameters of the nanorods range from 16 to 60 nm, and their lengths are 0.5 mu approximately 1.3mu. FT-IR spectrum, room-temperature PL, and UV-Vis absorption spectra are also discussed. A possible growth mechanism is proposed. Complex multiple forklike ZnO nanostructure was first used to construct a novel enzymatic biosensor based on the ZnO/CHIT inorganic-organic composite film. Well-studied horseradish peroxidase (HRP) was chosen as a model enzyme. The as-prepared biosensor displays ultrahigh sensitivity, quick response time, low detection limit and small apparent Michaelis-Menten constant. These results show that the Complex multiple forklike ZnO nanostructure is a promising material to construct enzyme biosensors.

Substrate-free growth, characterization and growth mechanism of ZnO nanorod close-packed arrays.

ZnO nanorod close-packed arrays are successfully fabricated in a substrate-free manner by a citric acid assisted annealing process at a low growth temperature of 400 °C. Each nanorod of ZnO nanorod close-packed arrays grows along the [0001] direction and is single crystalline with an average diameter of 50 nm, and an average length of 0.5 µm. The aspect ratio is 10. The ZnO nanorod close-packed arrays show a strong exciton absorption peak at 372 nm in UV-visible absorption spectra, exhibiting a blue-shift relative to the bulk exciton absorption (387 nm). Finally, a new growth mechanism is proposed for the substrate-free preparation of ZnO nanorod close-packed arrays by a citric acid assisted annealing process.

[Sludge characteristics in an aerobic granular sludge membrane bioreactor].

Granular sludge membrane bioreactor (GMBR), operated with alternating anaerobic-aerobic mode, showed good organics removal and simultaneous nitrification and denitrification (SND) performances during 120 days operation. Moreover, sludge size distribution examination showed that the increase of sludge concentration in GMBR was mostly due to the increase of small granular sludge with diameter between 0.18 - 0.45 mm and flocculent sludge smaller than 0.18 mm, and most of granular sludge larger than 0.45 mm was stably existed in GMBR, at the end of operation granular sludge with diameter larger than 0.18mm remained 60%-65% in GMBR. Sludge surface negative charge increased with the sludge size distribution variation, and surface charge remained -0.42 - -0.80 meq x g(-1) after 80 days operation. The increase of sludge surface negative charge was mostly caused by sludge smaller than 0.45 mm, thereinto sludge smaller than 0.18 mm had the greatest effect. Moreover, results revealed that the sludge surface negative charge decreased as the sludge size increased, and a linear correlation can be obtained between sludge surface negative charge and sludge size. Sludge in GMBR had good settleability, and SVI was about 60-90 mL/g. Furthermore results showed that sludge surface charge was correlated with SVI, sludge SVI increased with surface negative charge increased.