Oriented regulation of earthworm production and vermicompost quality by carbon bioavailability management.

Vermicomposting is an efficient bioconversion technology for recycling nutrients from organic waste materials. The biodegradability of raw materials has a significant impact on the earthworm transformation product. However, the management of carbon bioavailability is often overlooked during the vermicomposting process due to the varying degradability of C-rich source in different organic waste. This research aims to investigate the impact of different bioavailable carbon compositions on vermicomposting and to develop a strategy for efficient carbon management. The study involved systematic vermicomposting using four different biodegradable carbon sources (pineapple peels, rice straw, tomato straw, and sawdust) with varying carbon­nitrogen ratios (ranging from 24 to 42). The earthworm production and vermicompost quality were comprehensively evaluated, along with the influence of carbon components on microbial community structure. The results indicated that the optimal vermicomposting treatments were achieved at PCM24, RCM30, TCM30, and MCM30 treatments. Maintaining an approximate ratio of 1:(0.5-1.3) between available and recalcitrant carbon components based on the optimal carbon­nitrogen ratio was found to be optimal for regulating vermicomposting products. Increasing the proportion of available carbon enhanced the quality of vermicompost fertilizer, while a higher proportion of recalcitrant carbon could improve earthworm biomass production efficiency. Labile carbon proportion I (LCP1) and available carbon component (ACC) were identified as key indicators in influencing the formation of microbial community structure. Different carbon compositions led to the specific development and formation of microbial communities, further resulting in significant variations in vermicompost quality under the mediation of microbes. This study, for the first time, clarifies the impact of vermicomposting performance and microbial community from the perspective of carbon bioavailability, which is of great significance for the oriented regulation the vermicomposting efficiency and product in practice.

Correction: Burden of disease and risk factors for mortality amongst hospitalized newborns in Nigeria and Kenya.

[This corrects the article DOI: 10.1371/journal.pone.0244109.].

Plant-derived biochar amendment for compost maturity improvement and gaseous emission reduction in food waste composting: Insight from bacterial community and functions.

This study assessed the impact of different plant-derived biochar (cornstalk, rice husk, and sawdust) on bacterial community and functions for compost maturity and gaseous emissions during the composting of food waste. Results showed that all biochar strengthened organic biotransformation and caused a higher germination index on day 12 (over 100%), especially for rice husk biochar to enhance the growth of Thermobifida related to aerobic chemoheterotrophy. Rice husk biochar also achieved a relatively higher reduction efficiency of methane (85.8%) and ammonia (82.7%) emissions since its greater porous structure. Besides, the growth of Pseudomonas, Pusillimonas, and Desulfitibacter was restricted to constrict nitrate reduction, nitrite respiration, and sulfate respiration by optimized temperature and air permeability, thus reducing nitrous oxide and hydrogen sulfide emissions by 48.0-57.3% by biochar addition. Therefore, rice husk biochar experienced the optimal potential for maturity increment and gaseous emissions mitigation.

Accelerating the humification of mushroom waste by regulating nitrogen sources composition: Deciphering mechanism from bioavailability and molecular perspective.

Regulating nitrogen source composition is efficient approach to accelerate the spent mushroom substrate (SMS) composting process. However, currently, most traditional composting study only focuses on total C/N ratio of initial composting material. Rarely research concerns the effect of carbon or nitrogen components at different degradable level and their corresponding decomposed-substances on humification process. This study deciphers and compares the mechanism of mixed manure-N sources on SMS humification from bioavailability and molecular perspective. Two different biodegradable manure-N sources, cattle manure (CM) and Hainan chicken manure (CH), were added into the SMS composting with the different CM:CH ratio of 1:0, 3:1, 1:1, 1:3, and 0:1, respectively. The physicochemical properties and humic substances were determined to evaluate the compost quality. Coupling analysis of spectroscopy, fluorescence, and humic intermediate precursors were conducted to characterizing molecular formation process of humic acid (HA). The results indicated that regulating the carbon-nitrogen nutrient biodegradability of composting material by adding mixed nitrogen sources is an effective strategy to accelerate the SMS humification process. The C1H3 (CM:CH ratio of 1:3) and CH treatments obtained great physicochemical properties and the highest growth rate of HA (31.96% and 27.02%, respectively). The rapid reaction of polysaccharide, ketone, quinone, and amide in DOM (LCP1) might be the key for the fast humification in C1H3 and CH. The polyphenol, reducing sugar and amino acid originated from the labile-carbon-proportion I (LCP1) and recalcitrant-carbon-proportion (RCP), labile-carbon-proportion II (LCP2) and RCP, and labile-nitrogen-proportion I (LNP1), respectively, were the main driving intermediate precursors for the formation of HA. This study deciphers the SMS humification mechanism at molecular level and provides a strategy in accelerating-regulating the composting process. which will be beneficial for enhancing the disposing efficiency of SMS, producing high-quality organic fertilizer, and even popularizing to the similar types of organic waste in practical field.

Insight into humification of mushroom residues under addition of Rich-N sources: Comparing key molecular evolution processes using EEM-PARAFAC and 2D-FTIR-COS analysis.

Accelerating the humification of organic solid waste is one of the most important issues in composting. This present study aims to study and compare the humification process of different rich-N sources (chicken manure, cattle manure, and urea) addition during the composting of mushroom residues, from macro physicochemical properties to micro humic molecular structure evolution process. The physicochemical elements and humic components were determined for evaluating the compost quality and humification degree as composting proceed. The coupled analysis of excitation-emission matrix with parallel factor analysis (EEM-PARAFAC) and two-dimensional correlation with Fourier transform infrared spectrum (2D-FTIR-COS) were used to characterize the functional molecular structure evolution of dissolved organic matter during humification process. The results indicated that the rank order for humification level were the treatments of chicken manure (HM), urea (UM), cattle manure (CM), and single mushroom residue treatment (CK), with their humification index of 22.18%, 22.05%, 18.47%, and 16.52%, respectively. Humic substance, humic acid, and fulvic acid were obtained the highest in HM treatment with contents of 35.41 ± 0.86%, 23.32 ± 1.57%, and 10.97 ± 0.52%, respectively. The rich-N source addition enhanced the degradation of protein-like and polysaccharides-like substances in dissolved organic matter, thus accelerating the humification process of mushroom residues. The key structure evolution of dissolved organic matter in the HM treatment, in which the CO and CC stretching of quinone, amide, or ketone, and the C-O stretching of polysaccharides may be responsible for the faster formation of humus compared to the other nitrogen treatments. In this study, redundancy analysis indicated that the total nitrogen (TN) and nitrate nitrogen (NO3--N) may be the potential indicators for determining the humification level as composting proceed. The result provides significant insight into the humification mechanism of mushroom residue under different types of nitrogen sources at the molecular level, and will be reference for improving the composting technique in practical field.

High-normal liver enzyme levels in early pregnancy predispose the risk of gestational hypertension and preeclampsia: A prospective cohort study.

Background: Gestational hypertension (GH) and preeclampsia (PE) are severe adverse gestational complications. Previous studies supported potential link between elevated liver enzyme levels and GH and PE. However, given the transient physiological reduction of liver enzyme levels in pregnancy, little is known whether the associations of the high-normal liver enzyme levels in early pregnancy with GH and PE exist in pregnant women. Methods: Pregnant women in this study came from a sub-cohort of Shanghai Preconception Cohort, who were with four liver enzyme levels examined at 9-13 gestational weeks and without established liver diseases, hypertension and preeclampsia. After exclusion of pregnant women with clinically-abnormal liver enzyme levels in the current pregnancy, associations of liver enzyme levels, including alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase (GGT), with GH and PE status were assessed by multivariable log-binomial regression. Population attributable fraction was measured to estimate the fractions of GH and PE that were attributable to the high-normal liver enzyme levels. Results: Among 5,685 pregnant women 160 (2.8%) and 244 (4.3%) developed GH and PE, respectively. After adjustment for potential covariates, higher ALP, ALT and GGT levels were significantly associated with the risk of GH (adjusted risk ratio (aRR):1.21 [95% confidence interval, 1.05-1.38]; 1.21 [1.05-1.38]; and 1.23 [1.09-1.39]), as well as the risk of PE(1.21 [1.13-1.29]; 1.15 [1.03-1.28]; 1.28 [1.16-1.41]), respectively. The cumulative population attributable fraction of carrying one or more high-normal liver enzyme levels (at 80th percentile or over) was 31.4% for GH and 23.2% for PE, respectively. Conclusion: Higher ALT, ALP and GGT levels within the normal range in early pregnancy are associated with increased risk of GH and PE. The documented associations provide new insight to the role of hepatobiliary function in GH and PE pathogenesis.

Periconception Red Blood Cell Folate and Offspring Congenital Heart Disease : Nested Case-Control and Mendelian Randomization Studies.

BACKGROUND: Periconception folic acid supplementation has been suggested to protect against congenital heart disease (CHD), but the association between maternal red blood cell (RBC) folate, the gold-standard biomarker of folate exposure, and subsequent offspring CHD risk is lacking. OBJECTIVE: To quantify the association between periconception maternal RBC folate and offspring CHD risk. DESIGN: Prospective, nested, case-control study and 1-sample Mendelian randomization. (ClinicalTrials.gov: NCT02737644). SETTING: 29 maternity institutions in 12 districts of Greater Shanghai, China. PARTICIPANTS: All 197 mothers of offspring with CHD and 788 individually matched mothers of unaffected offspring from the SPCC (Shanghai Preconception Cohort). MEASUREMENTS: Maternal RBC folate was measured before or at early pregnancy. Odds ratios [ORs] were estimated using conditional logistic regression after adjustment for covariates. Mendelian randomization was done using the methylenetetrahydrofolate reductase (MTHFR) C677T as the genetic instrument. RESULTS: Case patients had lower median maternal RBC folate concentrations than control participants (714 nmol/L [interquartile range, 482 to 1008 nmol/L] vs. 788 nmol/L [557 to 1094 nmol/L]). Maternal RBC folate concentrations were inversely associated with offspring CHD (adjusted OR per 100 nmol/L, 0.93 [95% CI, 0.89 to 0.99]). The adjusted OR for mothers with periconception RBC folate of 906 nmol/L or more (vs. <906 nmol/L) was 0.61 (CI, 0.40 to 0.93). Mendelian randomization showed that each 100-nmol increase in maternal RBC folate concentrations was significantly associated with reduced offspring CHD risk (OR, 0.75 [CI, 0.61 to 0.92]). LIMITATION: Potential confounding due to unmeasured covariates in the nested case-control study. CONCLUSION: Higher maternal RBC folate is associated with reduced offspring CHD risk. For primary CHD prevention, higher target RBC folate levels than currently recommended for neural tube defect prevention may be needed and warrant further study. PRIMARY FUNDING SOURCE: National Key Research and Development Program of China, National Natural Science Foundation of China, China Postdoctoral Science Foundation, and Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences.

RBC Folate and Serum Folate, Vitamin B-12, and Homocysteine in Chinese Couples Prepregnancy in the Shanghai Preconception Cohort.

BACKGROUND: The protective effects of maternal folate on neural tube defects are well-established. Emerging evidence has shown paternal folate also is related to pregnancy outcome and offspring health. OBJECTIVES: This study aimed to assess the status of red blood cell (RBC) folate and serum folate, vitamin B-12, and homocysteine (Hcy) and their associated factors in a cohort of pregnancy-preparing couples. METHODS: This was a cross-sectional study involving 14,178 participants from the extension of the Shanghai Preconception Cohort conducted in 2018-2021. Circulating biomarker concentrations were measured, and the prevalence of abnormal status was reported. Linear and logistic regression analyses were conducted to examine associations of demographic factors (age, education, and income), lifestyle factors (smoking, drinking, and folic acid supplement use), and BMI with concentrations of the folate-related biomarkers, abnormal status of folate (deficiency and insufficiency) and vitamin B-12 (deficiency and marginal deficiency), and hyperhomocysteinemia. RESULTS: The geometric mean (95% CI) concentrations of RBC folate, serum folate, vitamin B-12, and Hcy were 490 nmol/L (485, 496 nmol/L), 20.1 nmol/L (19.8, 20.3 nmol/L), 353 pmol/L (350, 357 pmol/L), and 7.54 µmol/L (7.48, 7.60 µmol/L) in females, respectively, and 405 nmol/L (401, 409 nmol/L), 13.5 nmol/L (13.4, 13.7 nmol/L), 277 pmol/L (274, 279 pmol/L), and 12.0 µmol/L (11.9, 12.2 µmol/L) in males, respectively. Prevalence of abnormal status was higher in males than females for the 4 folate-related biomarkers: RBC folate deficiency (<340 nmol/L, 32.2% compared with 18.9%), serum folate deficiency (<10.0 nmol/L, 26.5% compared with 7.3%), RBC folate insufficiency (<906 nmol/L, 96.6% compared with 90.1%), serum folate insufficiency (<15.9 nmol/L, 65.5% compared with 31.4%), vitamin B-12 marginal deficiency (148-221 pmol/L, 21.4% compared with 8.8%), and hyperhomocysteinemia (>15.0 µmol/L, 22.1% compared with 2.5%). CONCLUSIONS: Most pregnancy-preparing couples failed to achieve the optimal RBC folate status (>906 nmol/L) as recommended by the WHO. These findings call for attention to the insufficiency status of folate and promising strategies to improve the folate status of the pregnancy-preparing population not exposed to folic acid fortification.

Maternal liver dysfunction in early pregnancy predisposes to gestational diabetes mellitus independent of preconception overweight: A prospective cohort study.

OBJECTIVE: To evaluate whether the associations of maternal liver dysfunction and liver function biomarkers (LFBs) with gestational diabetes mellitus (GDM) are independent of overweight. DESIGN: Prospective cohort study. METHODS: A sub-cohort of pregnant women with seven LFBs examined at 9-13 weeks of gestation and with complete GDM evaluation at mid-gestation were extracted from the prospective Shanghai Preconception Cohort Study. Associations of liver dysfunction, defined as having any elevated LFB levels, and individual LFB levels with GDM incidence were assessed by adjusting body mass index and other covariates in the multivariable logistic regression model. Odds ratios (ORs) and 95% CI were reported. MAIN OUTCOME MEASURES: Incident GDM. RESULTS: Among 6211 pregnant women, 975 (15.7%) developed GDM. Liver dysfunction was associated with increased odds of GDM (OR 1.63; 95% CI 1.38-1.92). This association persisted after adjustment for BMI (adjusted OR [aOR] 1.37; 95% CI 1.15-1.63). Higher γ-glutamyl transferase, alanine aminotransferase, alkaline phosphatase, and albumin levels were also linked with GDM (aOR per 1 SD: 1.15, 95% CI 1.08-1.23; 1.10, 1.03-1.17; 1.21, 1.13-1.29 and 1.19, 1.11-1.27, respectively). Similar magnitudes of associations were observed between normal weight and overweight pregnant women. CONCLUSION: Maternal liver dysfunction in early pregnancy predisposes women to subsequent GDM, and this association is independent of being overweight preconception. Our findings of an increased risk even in normal-weight pregnant women adds new mechanistic insights about the pathophysiological role of liver function in GDM aetiology. TWEETABLE ABSTRACT: Maternal liver dysfunction in early pregnancy is associated with GDM incidence independent of preconception overweight.

Burden of disease and risk factors for mortality amongst hospitalized newborns in Nigeria and Kenya.

OBJECTIVE: To describe the patient population, priority diseases and outcomes in newborns admitted <48 hours old to neonatal units in both Kenya and Nigeria. STUDY DESIGN: In a network of seven secondary and tertiary level neonatal units in Nigeria and Kenya, we captured anonymised data on all admissions <48 hours of age over a 6-month period. RESULTS: 2280 newborns were admitted. Mean birthweight was 2.3 kg (SD 0.9); 57.0% (1214/2128) infants were low birthweight (LBW; <2.5kg) and 22.6% (480/2128) were very LBW (VLBW; <1.5 kg). Median gestation was 36 weeks (interquartile range 32, 39) and 21.6% (483/2236) infants were very preterm (gestation <32 weeks). The most common morbidities were jaundice (987/2262, 43.6%), suspected sepsis (955/2280, 41.9%), respiratory conditions (817/2280, 35.8%) and birth asphyxia (547/2280, 24.0%). 18.7% (423/2262) newborns died; mortality was very high amongst VLBW (222/472, 47%) and very preterm infants (197/483, 40.8%). Factors independently associated with mortality were gestation <28 weeks (adjusted odds ratio 11.58; 95% confidence interval 4.73-28.39), VLBW (6.92; 4.06-11.79), congenital anomaly (4.93; 2.42-10.05), abdominal condition (2.86; 1.40-5.83), birth asphyxia (2.44; 1.52-3.92), respiratory condition (1.46; 1.08-2.28) and maternal antibiotics within 24 hours before or after birth (1.91; 1.28-2.85). Mortality was reduced if mothers received a partial (0.51; 0.28-0.93) or full treatment course (0.44; 0.21-0.92) of dexamethasone before preterm delivery. CONCLUSION: Greater efforts are needed to address the very high burden of illnesses and mortality in hospitalized newborns in sub-Saharan Africa. Interventions need to address priority issues during pregnancy and delivery as well as in the newborn.

Association of Maternal Folate and Vitamin B12 in Early Pregnancy With Gestational Diabetes Mellitus: A Prospective Cohort Study.

OBJECTIVE: To investigate the association of folate and vitamin B12 in early pregnancy with gestational diabetes mellitus (GDM) risk. RESEARCH DESIGN AND METHODS: The data of this study were from a subcohort within the Shanghai Preconception Cohort Study. We included pregnancies with red blood cell (RBC) folate and vitamin B12 measurements at recruitment (between 9 and 13 gestational weeks) and those with three samples available for glucose measurements under an oral glucose tolerance test. GDM was diagnosed between 24 and 28 weeks' gestation. Odds ratio (OR) and 95% CI of having GDM was used to quantify the association. RESULTS: A total of 1,058 pregnant women were included, and GDM occurred in 180 (17.01%). RBC folate and vitamin B12 were significantly higher in pregnancies with GDM than those without GDM (P values were 0.045 and 0.002, respectively) and positively correlated with 1-h and 2-h serum glucose. Daily folic acid supplementation in early pregnancy increases the risk of GDM; OR (95% CI) was 1.73 (1.19-2.53) (P = 0.004). Compared with RBC folate <400 ng/mL, pregnancies with RBC folate ≥600 ng/mL were associated with ∼1.60-fold higher odds of GDM; the adjusted OR (95% CI) was 1.58 (1.03-2.41) (P = 0.033). A significant trend of risk effect on GDM risk across categories of RBC folate was observed (P trend = 0.021). Vitamin B12 was significantly associated with GDM risk (OR 1.14 per 100 pg/mL; P = 0.002). No significant association of serum folate and percentile ratio of RBC folate/vitamin B12 with GDM was observed. CONCLUSIONS: Higher maternal RBC folate and vitamin B12 levels in early pregnancy are significantly associated with GDM risk, while the balance of folate/vitamin B12 is not significantly associated with GDM.

Effectiveness of community-based folate-oriented tertiary interventions on incidence of fetus and birth defects: a protocol for a single-blind cluster randomized controlled trial.

BACKGROUND: Birth defects are the main cause of fetal death, infant mortality and morbidity worldwide. However, the etiology of birth defects remains largely unknown. Maternal folate status during periconception plays an important role in organogenesis and folic acid supplement reduces the risk of neural tube defects, congenital heart diseases, and several other birth defects. This trial seeks to evaluate the effectiveness of folate-oriented tertiary interventions during periconception on the incidence of fetus and birth defects. METHODS: This is a single-blind, two-arm cluster randomized controlled trial in Shanghai, China. Eligible women from 22 clusters are recruited at pre-pregnancy physical examinations clinical settings. Compared to the routine perinatal care group (control arm), folate-oriented tertiary interventions will be provided to the intervention arm. The core interventions consist of assessments of folate status and metabolism, folate intake guidance, and re-evaluation of folate status to ensure red blood cell folate level above 400 ng/ml (906 nmol/L) before pregnancy. Screening and consulting of fetus and birth defects, and treatments of birth defects during pregnancy and afterward will be provided to both arms. The primary outcome is a composite incidence of fetus defects, stillbirth, and neonatal birth defects identified from the confirmation of pregnancy to 28 days after birth. Secondary outcomes include maternal and offspring adverse complications and cost-effectiveness of folate-oriented tertiary interventions. This protocol adheres to the SPIRIT Checklist. DISCUSSION: To achieve the recommended folate status before or during pregnancy is still a challenge worldwide. This community-based cluster-randomized controlled intervention trial will evaluate the effectiveness of a package of interventions aiming at achieving recommended maternal folate status covering pre- and during pregnancy in reducing fetus and birth defects. Our study has the potential to improve the community-based practice of reducing modifiable risk factors of disease and improving primary prevention of the defects in China. The procedures would formulate the policy on folic acid supplementation during periconception against birth defects in primary care settings. TRIAL REGISTRATION: Clinical Trial Registry, NCT03725878 . Prospectively registered on 31 October 2018.

Shanghai Preconception Cohort (SPCC) for the association of periconceptional parental key nutritional factors with health outcomes of children with congenital heart disease: a cohort profile.

PURPOSE: The Shanghai Preconception Cohort (SPCC) was initially established to investigate the associations of parental periconceptional nutritional factors with congenital heart disease (CHD) but has further analysed child growth and development and paediatric diseases. PARTICIPANTS: Preparing-for-pregnancy couples who presented at Shanghai preconception examination clinics and early-pregnancy women before 14 gestational weeks were enrolled to comprise the periconceptional baseline study population. General characteristics, routine clinical data and consumption of diet supplements, such as folic acid and multivitamins, were collected. Blood samples were obtained at preconception and early, middle and late gestations using standard procedures. Multiple nutritional factors, including folate, homocysteine, vitamin A, vitamin D, vitamin E and metals, in the blood samples of participants selected using a case-control design were examined. Genomic DNA was extracted. FINDINGS TO DATE: The baseline population included 8045 preconception couples, 3054 single women and 15 615 early-pregnancy women. Data from 12 402 births were collected, and follow-up of the cohort for other outcomes is ongoing. Currently, 151 cases of CHD were identified after birth. The pilot analysis in a small subgroup showed that approximately 20.0% of preconception women and 44.9% of early-pregnancy women had red blood cell (RBC) folate levels that met the international recommendation for preventing neural tube defects. FUTURE PLANS: Once a sufficient number of CHD cases are achieved, we will investigate the quantitative association of preconception RBC folate levels with CHD using a nested case-control design. The SPCC will be followed up for 18 years to investigate extensive outcomes of growth, development, obesity, and common and rare diseases during childhood and adolescence according to our plan. Blood nutritional factors will be examined in participants selected for specific aims. The SPCC will also allow for prospective cohort studies on extensive research questions. TRIAL REGISTRATION NUMBER: NCT02737644.

Enhanced dewaterability of waste-activated sludge by combined cationic polyacrylamide and magnetic field pretreatment.

The potential function of combining magnetic field (MF) pretreatment with cationic polyacrylamide (CPAM) additive on enhancing the dewaterability of waste-activated sludge was investigated in the present work. Two reactors were involved in a specially designed experimental apparatus, one of which was built with MF accessories. Several parameters were conducted, including CPAM dosages, MF strengths and processing times, respectively. Capillary suction time (CST) and specific resistance to filtration (SRF) were used to evaluate sludge dewaterability. Extracellular polymeric substances (EPS) concentration was also determined in an attempt to identify the observed changes in dewaterability. It was indicated by the results that both CPAM conditioning and MF pretreatment on sludge can lower CST and SRF values. However, subjecting to a combination of MF pretreatment and CPAM conditioning, sludge dewaterability was significantly enhanced beyond the level observed of CPAM addition alone. The lowest CST and SRF values of 36.5 s and 0.75×10(12) m kg(-1), respectively, were obtained when sludge was co-conditioned by CPAM (at a dosage of 40 mg L(-1)) and MF (at an induction of 40 mT) for 30 min, suggesting the optimal condition for enhancing sludge dewaterability. It is also shown from the significant correlations between EPS, protein, polysaccharide and CST/SRF that the increment of EPS concentration in sludge supernatant may be the major reason for the enhancement of dewaterability.

Sewage sludge biochar as an efficient catalyst for oxygen reduction reaction in an microbial fuel cell.

Sewage sludge (SS) biochars have been prepared under an inert atmosphere at different temperatures. Morphologic and chemical analyses reveal that the surface of the biochar carbonized at 900°C (SS900) has more abundant micropores, and higher nitrogen and iron contents as compared to those carbonized at 500 (SS500) and 700°C (SS700). The electrochemical analyses display that the prepared biochars are active for catalyzing oxygen reduction reaction (ORR). However, more positive peak potential and larger peak current of ORR are found using the SS900 as compared to the SS500 and SS700. In MFCs, the maximum power density of 500±17 mW m(-2) was obtained from the SS900 cathode, which is comparable to the Pt cathode. The proposed cathode exhibited good stability and great tolerance to methanol. Given these results, it is expected that the SS-derived biochar cathode can find application in fuel cell systems.

Bacillus thermotolerans sp. nov., a thermophilic bacterium capable of reducing humus.

A novel thermotolerant bacterium, designated SgZ-8(T), was isolated from a compost sample. Cells were non-motile, endospore-forming, Gram-staining positive, oxidase-negative and catalase-positive. The isolate was able to grow at 20-65 °C (optimum 50 °C) and pH 6.0-9.0 (optimum 6.5-7.0), and tolerate up to 9.0 % NaCl (w/v) under aerobic conditions. Anaerobic growth occurred with anthraquinone-2,6-disulphonate (AQDS), fumarate and NO3(-) as electron acceptors. Phylogenetic analysis based on the16S rRNA and gyrB genes grouped strain SgZ-8(T) into the genus Bacillus, with the highest similarity to Bacillus badius JCM 12228(T) (96.2 % for 16S rRNA gene sequence and 83.5 % for gyrB gene sequence) among all recognized species in the genus Bacillus. The G+C content of the genomic DNA was 49.3 mol%. The major isoprenoid quinone was menaquinone 7 (MK-7) and the polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The major cellular fatty acid was iso-C16 : 0. On the basis of its phenotypic and phylogenetic properties, chemotaxonomic analysis and the results of physiological and biochemical tests, strain SgZ-8(T) ( = CCTCC AB 2012108(T) = KACC 16706(T)) was designated the type strain of a novel species of the genus Bacillus, for which the name Bacillus thermotolerans sp. nov. is proposed.