67 research outputs found

    Microbiological and Technological Insights on Anaerobic Digestion of Animal Manure: A Review

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    Anaerobic digestion of animal manure results in the production of renewable energy (biogas) and nutrient-rich biofertilizer. A further benefit of the technology is decreased greenhouse gas emissions that otherwise occur during manure storage. Since animal manure makes anaerobic digestion cost-efficient and further advance the technology for higher methane yields, it is of utmost importance to find strategies to improve bottlenecks such as the degradation of lignocellulose, e.g., in cattle manure, or to circumvent microbial inhibition by ammonia caused by the degradation of nitrogen compounds in, e.g., chicken, duck, or swine manure. This review summarizes the characteristics of different animal manures and provides insight into the underlying microbial mechanisms causing challenging problems with the anaerobic digestion process. A particular focus is put upon the retention time and organic loading rate in high-ammonia processes, which should be designed and optimized to support the microorganisms that tolerate high ammonia conditions, such as the syntrophic acetate oxidizing bacteria and the hydrogenotrophic methanogens. Furthermore, operating managements used to stabilize and increase the methane yield of animal manure, including supporting materials, the addition of trace elements, or the incorporation of ammonia removal technologies, are summarized. The review is finalized with a discussion of the research needed to outline conceivable operational methods for the anaerobic digestion process of animal manure to circumvent process instability and improve the process performance

    A novel microfluidic resistive pulse sensor with multiple voltage input channels and a side sensing gate for particle and cell detection

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    The final publication is available at Elsevier via https://doi.org/10.1016/j.aca.2018.11.049. © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Traditionally, a resistive pulse sensor (also known as Coulter counter) works by letting a particle pass through a small orifice in an electrolyte solution. The detection sensitivity mainly relies on the volume ratio of the particle to the orifice. This paper presents a novel resistive pulse sensor which has a sensing orifice located on the side wall of a microchannel. In this way, the sensor can detect and count particles (or cells) without requiring particles (or cells) passing through the sensing gate. An equation was derived to relate the magnitudes of the detected signals and the electrical resistances. Results show that the magnitudes of the detected signals can be increased by applying voltages from more than one voltage input channels simultaneously. Under the same conditions, the magnitudes of the detected signals become larger when the diameters of particles are larger. Higher detection sensitivity can be obtained simply by increasing either the magnitudes of the applied voltages or the number of the voltage input channels, or reducing the opening of the side sensing gate to a size that is even smaller than the diameter of the particle. Due to the high detection sensitivity, detection of 1 μm particles by a relatively large sensing gate of 5 × 10 × 10 μm (width × length × height) was successfully demonstrated with a signal to noise ratio (S/N) of approximately 3. This sensor was also applied to detect and count human red blood cells and lymphocyte cells. Results show that this method can clearly distinguish the cells with different sizes based on the pre-determined-thresholds. Because this sensor does not require cells to pass through the sensing gate, the channel clogging problem can be avoided. More importantly, the detection sensitivity can be tuned by applying different voltages without fabricating a smaller sensing gate.The authors wish to acknowledge financial support of National Natural Science Foundation program of China (51679023) and Liaoning BaiQianWan Talents Program to Yongxin Song; the Natural Sciences and Engineering Research Council of Canada through a research grant to D. Li, the support from Fundamental Research Funds for the Central Universities (3132016325) and from the University 111 project of China under Grant No. B08046 is greatly appreciated

    A Deep-learning Real-time Bias Correction Method for Significant Wave Height Forecasts in the Western North Pacific

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    Significant wave height is one of the most important parameters characterizing ocean waves, and accurate numerical ocean wave forecasting is crucial for coastal protection and shipping. However, due to the randomness and nonlinearity of the wind fields that generate ocean waves and the complex interaction between wave and wind fields, current forecasts of numerical ocean waves have biases. In this study, a spatiotemporal deep-learning method was employed to correct gridded SWH forecasts from the ECMWF-IFS. This method was built on the trajectory gated recurrent unit deep neural network,and it conducts real-time rolling correction for the 0-240h SWH forecasts from ECMWF-IFS. The correction model is co-driven by wave and wind fields, providing better results than those based on wave fields alone. A novel pixel-switch loss function was developed. The pixel-switch loss function can dynamically fine-tune the pre-trained correction model, focusing on pixels with large biases in SWH forecasts. According to the seasonal characteristics of SWH, four correction models were constructed separately, for spring, summer, autumn, and winter. The experimental results show that, compared with the original ECMWF SWH predictions, the correction was most effective in spring, when the mean absolute error decreased by 12.972~46.237%. Although winter had the worst performance, the mean absolute error decreased by 13.794~38.953%. The corrected results improved the original ECMWF SWH forecasts under both normal and extreme weather conditions, indicating that our SWH correction model is robust and generalizable.Comment: 21 page

    Genotype-phenotype correlation in patients with 21-hydroxylase deficiency.

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    INTRODUCTION: 21-hydroxylase deficiency (21OHD) is the most common cause of congenital adrenal hyperplasia (CAH). However, patients with 21OHD manifest various phenotypes due to a wide-spectrum residual enzyme activity of different CYP21A2 mutations. METHODS: A total of 15 individuals from three unrelated families were included in this study. Target Capture-Based Deep Sequencing and Restriction Fragment Length Polymorphism was conducted on peripheral blood DNA of the three probands to identify potential mutations/deletions in CYP21A2; Sanger sequencing was conducted with the DNA from the family members of the probands. RESULTS: Dramatically different phenotypes were seen in the three probands of CAH with different compound heterozygous mutations in CYP21A2. Proband 1 manifested simple virilizing with mutations of 30-kb deletion/c.[188A\u3eT;518T\u3eA], the latter is a novel double mutants classified as SV associated mutation. Although both probands carry the same compound mutations [293-13C\u3eG]:[518T\u3eA], gonadal dysfunction and giant bilateral adrenal myelolipoma were diagnosed for proband 2 and proband 3, respectively. CONCLUSION: Both gender and mutations contribute to the phenotypes, and patients with the same compound mutations and gender could present with different phenotypes. Genetic analysis could help the etiologic diagnosis, especially for atypical 21OHD patients

    Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) patient with ARMC5 mutations.

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    BACKGROUND: Primary bilateral macronodular adrenocortical hyperplasia (PBMAH) is a highly heterogeneous disease with divergent manifestations ranging from asymptomatic subclinical Cushing syndrome (CS) to overt Cushing syndrome with severe complications. ARMC5 mutations occur in 20 to 55% PBMAH patients usually with more severe phenotypes. Different ARMC5 mutations might be associated with diverse phenotypes of PBMAH. CASE PRESENTATION: A 39-year-old man was admitted to our hospital with progressive weight gain and severe hypertension. He presented typical CS and its classical metabolic and bone complications like hypertension and osteoporosis. The laboratory results showed high levels of cortisol and low levels of ACTH. Low- and high-dosed dexamethasone suppression tests were negative. Contrast-enhanced computed tomography (CT) revealed multiple bilateral irregular macronodular adrenal masses. Adrenal venous sampling (AVS) confirmed that the right adrenal gland with larger nodules secreted more hormone that the left side did. Right adrenalectomy and subsequent contralateral subtotal resection were conducted. His blood pressure and CS symptoms as well as comorbidities including backache and muscle weakness improved. Whole exome sequencing identified one ARMC5 germline mutation (c.1855C \u3e T, p. R619*), five ARMC5 somatic mutations (four novel mutations) in his right and left adrenal nodules. CONCLUSIONS: This PBMAH patient was identified with one ARMC5 germline mutation and five different somatic ARMC5 mutations (four novel mutations) in the different nodules of the bilateral adrenal masses. AVS combined with CT imagine could be helpful to determine the dominant side for adrenalectomy. Genetic testing is important for the diagnosis and management of the patient with PBMAH

    PHF8-GLUL axis in lipid deposition and tumor growth of clear cell renal cell carcinoma.

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    For clear cell renal cell carcinoma (ccRCC), lipid deposition plays important roles in the development, metastasis, and drug resistance. However, the molecular mechanisms underlying lipid deposition in ccRCC remain largely unknown. By conducting an unbiased CRISPR-Cas9 screening, we identified the epigenetic regulator plant homeodomain finger protein 8 (PHF8) as an important regulator in ccRCC lipid deposition. Moreover, PHF8 is regulated by von Hippel-Lindau (VHL)/hypoxia-inducible factor (HIF) axis and essential for VHL deficiency-induced lipid deposition. PHF8 transcriptionally up-regulates glutamate-ammonia ligase (GLUL), which promotes the lipid deposition and ccRCC progression. Mechanistically, by forming a complex with c-MYC, PHF8 up-regulates TEA domain transcription factor 1 (TEAD1) in a histone demethylation-dependent manner. Subsequently, TEAD1 up-regulates GLUL transcriptionally. Pharmacological inhibition of GLUL by l-methionine sulfoximine not only repressed ccRCC lipid deposition and tumor growth but also enhanced the anticancer effects of everolimus. Thus, the PHF8-GLUL axis represents a potential therapeutic target for ccRCC treatment

    INTEnsive ambulance-delivered blood pressure Reduction in hyper-ACute stroke Trial (INTERACT4) : study protocol for a randomized controlled trial

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    Background: Early pre-hospital initiation of blood pressure (BP) lowering could improve outcomes for patients with acute stroke, by reducing hematoma expansion in intracerebral hemorrhage (ICH), and time to reperfusion treatment and risk of intracranial hemorrhage in ischemic stroke (IS). We present the design of the fourth INTEnsive ambulance-delivered blood pressure Reduction in hyper-ACute stroke Trial (INTERACT4). Methods: A multi-center, ambulance-delivered, prospective, randomized, open-label, blinded endpoint (PROBE) assessed trial of pre-hospital BP lowering in 3116 hypertensive patients with suspected acute stroke at 50+ sites in China. Patients are randomized through a mobile phone digital system to intensive BP lowering to a target systolic BP of < 140 mmHg within 30 min, or guideline-recommended BP management according to local protocols. After the collection of in-hospital clinical and management data and 7-day outcomes, trained blinded assessors conduct telephone or face-to-face assessments of physical function and health-related quality of life in participants at 90 days. The primary outcome is the physical function on the modified Rankin scale at 90 days, analyzed as an ordinal outcome with 7 categories. The sample size was estimated to provide 90% power (α = 0.05) to detect a 22% reduction in the odds of a worse functional outcome using ordinal logistic regression. Discussion: INTERACT4 is a pragmatic clinical trial to provide reliable evidence on the effectiveness and safety of ambulance-delivered hyperacute BP lowering in patients with suspected acute stroke. Trial registration: ClinicalTrials.gov NCT03790800. Registered on 2 January 2019; Chinese Trial Registry ChiCTR1900020534. Registered on 7 January 2019. All items can be found in this protocol paper

    Process Performance and Functional Microbial Community in the Anaerobic Digestion of Chicken Manure: A Review

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    Anaerobic digestion is one of the most widely used treatment methods for animal manure. Chicken manure has high methane production potential and is thus a suitable substrate for biogas plants. However, high nitrogen content inhibits the metabolism of anaerobic microorganisms and thus hinders methane production from chicken manure. Enhancing the performance of anaerobic digestion for chicken manure is indeed a long-standing challenge. This review presents new insights into maintaining methanogens’ activities, the decomposition of acetate, and the dynamics of methanogenic pathways under high ammonia stress. This review also analyzed the possible strategies for alleviating ammonia inhibition effects, including supplementing trace elements, co-digestion with nitrogen-less materials, in-situ ammonia removal, and long adaptation of anaerobic consortia to ammonia stress. The insights obtained in this paper may provide helpful information for a better understanding of anaerobic digestion technology for chicken manure and other nitrogen-rich waste and wastewater

    Effect of Zero Water Exchange Systems for <i>Litopenaeus vannamei</i> Using Sponge Biocarriers to Control Inorganic Nitrogen and Suspended Solids Simultaneously

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    The traditional shrimp farming mode, which mainly uses water exchange to dilute toxic nitrogenous compounds, not only brings risks of disease infections and outbreaks but also results in waste of water resources and has a negative impact on the environment. In this study, zero water exchange systems for Litopenaeus vannamei were constructed by using sponge biocarriers with precultured biofilms (SBBFs), and the effect of SBBFs on controlling inorganic nitrogen, suspended solids and on the performance of L. vannamei was determined. The experiment consisted of four treatments: (1) SBC (control, SB 5% (v/v) + aeration); (2) SBBF2.5a (SBBF 2.5% (v/v) + aeration); (3) SBBF5a (SBBF 5% (v/v) + aeration); and (4) SBBF5 (SBBF 5% (v/v)). The results showed that the concentrations of TAN and NO2−-N in the SBBF treatments were significantly lower than those in the SBC treatments, while the SBBF treatments registered higher NO3−-N concentrations. After the adsorbates were removed by regular cleaning to regenerate the adsorption capacity of the SBs, the turbidity was reduced by 47.8%~71.5%. The shrimp grown in the SBBF treatments exhibited a higher mean final weight, survival and productivity than those grown in the SBC treatments. This work found that the use of SBBFs can maintain the low levels of TAN, NO2−-N and suspended solids while improving the performance of the L. vannamei under the strict requirement of zero water exchange

    Microbiological and Technological Insights on Anaerobic Digestion of Animal Manure: A Review

    No full text
    Anaerobic digestion of animal manure results in the production of renewable energy (biogas) and nutrient-rich biofertilizer. A further benefit of the technology is decreased greenhouse gas emissions that otherwise occur during manure storage. Since animal manure makes anaerobic digestion cost-efficient and further advance the technology for higher methane yields, it is of utmost importance to find strategies to improve bottlenecks such as the degradation of lignocellulose, e.g., in cattle manure, or to circumvent microbial inhibition by ammonia caused by the degradation of nitrogen compounds in, e.g., chicken, duck, or swine manure. This review summarizes the characteristics of different animal manures and provides insight into the underlying microbial mechanisms causing challenging problems with the anaerobic digestion process. A particular focus is put upon the retention time and organic loading rate in high-ammonia processes, which should be designed and optimized to support the microorganisms that tolerate high ammonia conditions, such as the syntrophic acetate oxidizing bacteria and the hydrogenotrophic methanogens. Furthermore, operating managements used to stabilize and increase the methane yield of animal manure, including supporting materials, the addition of trace elements, or the incorporation of ammonia removal technologies, are summarized. The review is finalized with a discussion of the research needed to outline conceivable operational methods for the anaerobic digestion process of animal manure to circumvent process instability and improve the process performance.
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