In Situ Real-Time Study on Dynamics of Microbially Induced Calcium Carbonate Precipitation at a Single-Cell Level

Ureolytic microbially induced calcium carbonate precipitation (MICP) is a promising green technique for addressing a variety of environmental and architectural concerns. However, the dynamics of MICP especially at the microscopic level remains relatively unexplored. In this work, by applying a bacterial tracking technique, the growth dynamics of micrometer-sized calcium carbonate precipitates induced by <i>Sporosarcina pasteurii</i> were studied at a single-cell resolution. The growth of micrometer-scale precipitates and the occurrence and dissolution of many unstable submicrometer calcium carbonate particles were observed in the precipitation process. More interestingly, we observed that micrometer-sized precipitated crystals did not grow on negatively charged cell surfaces nor on other tested polystyrene microspheres with different negatively charged surface modifications, indicating that a negatively charged surface was not a sufficient property for nucleating the growth of precipitates in the MICP process under the conditions used in this study. Our observations imply that the frequently cited model of bacterial cell surfaces as nucleation sites for precipitates during MICP is oversimplified. In addition, additional growth of calcium carbonates was observed on old precipitates collected from previous runs. The presence of bacterial cells was also shown to affect both morphologies and crystalline structures of precipitates, and both calcite and vaterite precipitates were found when cells physically coexisted with precipitates. This study provides new insights into the regulation of MICP through dynamic control of precipitation

In Situ Real-Time Study on Dynamics of Microbially Induced Calcium Carbonate Precipitation at a Single-Cell Level

Ureolytic microbially induced calcium carbonate precipitation (MICP) is a promising green technique for addressing a variety of environmental and architectural concerns. However, the dynamics of MICP especially at the microscopic level remains relatively unexplored. In this work, by applying a bacterial tracking technique, the growth dynamics of micrometer-sized calcium carbonate precipitates induced by <i>Sporosarcina pasteurii</i> were studied at a single-cell resolution. The growth of micrometer-scale precipitates and the occurrence and dissolution of many unstable submicrometer calcium carbonate particles were observed in the precipitation process. More interestingly, we observed that micrometer-sized precipitated crystals did not grow on negatively charged cell surfaces nor on other tested polystyrene microspheres with different negatively charged surface modifications, indicating that a negatively charged surface was not a sufficient property for nucleating the growth of precipitates in the MICP process under the conditions used in this study. Our observations imply that the frequently cited model of bacterial cell surfaces as nucleation sites for precipitates during MICP is oversimplified. In addition, additional growth of calcium carbonates was observed on old precipitates collected from previous runs. The presence of bacterial cells was also shown to affect both morphologies and crystalline structures of precipitates, and both calcite and vaterite precipitates were found when cells physically coexisted with precipitates. This study provides new insights into the regulation of MICP through dynamic control of precipitation

In Situ Real-Time Study on Dynamics of Microbially Induced Calcium Carbonate Precipitation at a Single-Cell Level

Ureolytic microbially induced calcium carbonate precipitation (MICP) is a promising green technique for addressing a variety of environmental and architectural concerns. However, the dynamics of MICP especially at the microscopic level remains relatively unexplored. In this work, by applying a bacterial tracking technique, the growth dynamics of micrometer-sized calcium carbonate precipitates induced by <i>Sporosarcina pasteurii</i> were studied at a single-cell resolution. The growth of micrometer-scale precipitates and the occurrence and dissolution of many unstable submicrometer calcium carbonate particles were observed in the precipitation process. More interestingly, we observed that micrometer-sized precipitated crystals did not grow on negatively charged cell surfaces nor on other tested polystyrene microspheres with different negatively charged surface modifications, indicating that a negatively charged surface was not a sufficient property for nucleating the growth of precipitates in the MICP process under the conditions used in this study. Our observations imply that the frequently cited model of bacterial cell surfaces as nucleation sites for precipitates during MICP is oversimplified. In addition, additional growth of calcium carbonates was observed on old precipitates collected from previous runs. The presence of bacterial cells was also shown to affect both morphologies and crystalline structures of precipitates, and both calcite and vaterite precipitates were found when cells physically coexisted with precipitates. This study provides new insights into the regulation of MICP through dynamic control of precipitation

Cross-validation results of Multi-Label classification on multifunctional enzymes only.

<p>Cross-validation results of Multi-Label classification on multifunctional enzymes only.</p

Distribution of multifunctional enzyme after de-redundance (0.9).

<p>Distribution of multifunctional enzyme after de-redundance (0.9).</p

Treatments for cesarean scar pregnancy: 11-year experience at a medical center

Cesarean scar pregnancy (CSP) is a long-term complication after cesarean section that can cause severe maternal morbidity and mortality. Although a variety of treatments have been described, there is no consensus as to the optimal management approach. Many grading systems for CSP have been proposed, among which the classification made by the consensus of Chinese experts in 2016 was shown to provide improved treatment guidance for clinical practice. The purpose of the present study was to analyze the success rate of different treatments for each type of CSP as classified according to the Chinese Expert’s Consensus (2016), and to develop a management strategy for CSP. A retrospective study was performed among patients diagnosed with CSP at Shandong Provincial Hospital between January 2009 and December 2019. We reviewed clinical characteristics, treatment methods, and subsequent outcomes; and analyzed these endpoints using the statistical software package SPSS 22.0 (SPSS, Inc., Chicago, IL). For type I CSP, systemic methotrexate (MTX) administration exhibited a success rate of 79.2% for type Ia and 14.3% for type Ib. Local and systemic MTX administration success rates were 88.9% for type Ia and 66.7% for type Ib. Dilation and curettage (D&C), curettage after uterine artery embolization (UAE + C), and hysteroscopic curettage (H + C) were 100% successful. For type II, UAE + C, H + C, and laparoscopy combined with hysteroscopic curettage (L + H+C) were 100% successful. D&C had a success rate of 97.0% for type IIa and 88.9% for type IIb. The success rate of systemic MTX administration was 52.0% for type IIa and 62.5% for type IIb. Both UAE + C and L + H+C had 100% success rates for type IIIa CSPs, while for type IIIb, the success rate was 87.9% for UAE + C vs. 96.6% for L + H+C. For type I CSPs, D&C was quick, easy, and safe; for type II, H + C was more suitable. For type III and some type II patients who wished to undergo simultaneous repair of the cesarean defect, L + H+C was the optimal method. UAE can be used as a complementary option instead of a prophylactic measure, and when difficulties with endoscopic surgeries were encountered, conversion to laparotomy was the ultimate treatment.</p

In Situ Real-Time Study on Dynamics of Microbially Induced Calcium Carbonate Precipitation at a Single-Cell Level

Ureolytic microbially induced calcium carbonate precipitation (MICP) is a promising green technique for addressing a variety of environmental and architectural concerns. However, the dynamics of MICP especially at the microscopic level remains relatively unexplored. In this work, by applying a bacterial tracking technique, the growth dynamics of micrometer-sized calcium carbonate precipitates induced by <i>Sporosarcina pasteurii</i> were studied at a single-cell resolution. The growth of micrometer-scale precipitates and the occurrence and dissolution of many unstable submicrometer calcium carbonate particles were observed in the precipitation process. More interestingly, we observed that micrometer-sized precipitated crystals did not grow on negatively charged cell surfaces nor on other tested polystyrene microspheres with different negatively charged surface modifications, indicating that a negatively charged surface was not a sufficient property for nucleating the growth of precipitates in the MICP process under the conditions used in this study. Our observations imply that the frequently cited model of bacterial cell surfaces as nucleation sites for precipitates during MICP is oversimplified. In addition, additional growth of calcium carbonates was observed on old precipitates collected from previous runs. The presence of bacterial cells was also shown to affect both morphologies and crystalline structures of precipitates, and both calcite and vaterite precipitates were found when cells physically coexisted with precipitates. This study provides new insights into the regulation of MICP through dynamic control of precipitation

Distribution of multifunctional enzymes before and after CD-HIT(0.65).

<p>Distribution of multifunctional enzymes before and after CD-HIT(0.65).</p

In Situ Real-Time Study on Dynamics of Microbially Induced Calcium Carbonate Precipitation at a Single-Cell Level

Ureolytic microbially induced calcium carbonate precipitation (MICP) is a promising green technique for addressing a variety of environmental and architectural concerns. However, the dynamics of MICP especially at the microscopic level remains relatively unexplored. In this work, by applying a bacterial tracking technique, the growth dynamics of micrometer-sized calcium carbonate precipitates induced by <i>Sporosarcina pasteurii</i> were studied at a single-cell resolution. The growth of micrometer-scale precipitates and the occurrence and dissolution of many unstable submicrometer calcium carbonate particles were observed in the precipitation process. More interestingly, we observed that micrometer-sized precipitated crystals did not grow on negatively charged cell surfaces nor on other tested polystyrene microspheres with different negatively charged surface modifications, indicating that a negatively charged surface was not a sufficient property for nucleating the growth of precipitates in the MICP process under the conditions used in this study. Our observations imply that the frequently cited model of bacterial cell surfaces as nucleation sites for precipitates during MICP is oversimplified. In addition, additional growth of calcium carbonates was observed on old precipitates collected from previous runs. The presence of bacterial cells was also shown to affect both morphologies and crystalline structures of precipitates, and both calcite and vaterite precipitates were found when cells physically coexisted with precipitates. This study provides new insights into the regulation of MICP through dynamic control of precipitation

Distribution of six enzyme classes before and after CD-HIT(0.65).

<p>Distribution of six enzyme classes before and after CD-HIT(0.65).</p