Analysis of standard unit carbon emission and cost assessment of the changing building envelope over material production phase.

It is undeniable that the material production stage is crucial to the whole life cycle of structures. This study proposes the window-to-envelope ratio (WER) based on standard units to determine the inherent relationship between changes in door and window areas and carbon emissions, presuming six distinct types of engineering practices for various buildings are selected. It was concluded that larger door and window areas would result in more embodied carbon emissions. Additionally, as the size of windows and doors increases, the costs and embodied carbon of prefabricated and cast-in-place construction become more comparable. According to the analysis, when the building scale is larger and the door and window opening area is also larger, prefabrication has more potential for saving carbon than cast-in-place building, but with a cost of approximately 10-20% higher. Considering the perspective of consumers, producers, and markets, this study revealed a costing assessment methodology based on standard units for prefabricated structures. In this methodology, producers choose and create various residential layouts based on the distinctive requirements of consumers, while tracking the trends in carbon emissions and production costs. This assessment method tries to create a favorable atmosphere for moral market activity and offers an acceptable solution for the trade-off between environmental and economic factors throughout the material production phase of the building.

Lightweight ZnO/Carbonated Cotton Fiber Nanocomposites for Electromagnetic Interference Applications: Preparation and Properties.

Electromagnetic wave pollution has become a significant harm posed to human health and precision instruments. To shelter such instruments from electromagnetic radiation, high-frequency electromagnetic interference (EMI) shielding materials are extremely desirable. The focus of this research is lightweight, high-absorption EMI shielding composites. Simple aqueous dispersion and drying procedures were used to prepare cotton fiber (CF)-based sheets combined with various zinc oxide (ZnO) contents. These composites were carbonated in a high-temperature furnace at 800 °C for two hours. The obtained CF/ZnO samples have densities of 1.02-1.08 g/cm3. The EMI shielding effectiveness of CF-30% ZnO, CF-50% ZnO, and CF-70% ZnO reached 32.06, 38.08, and 34.69 dB, respectively, to which more than 80% of absorption is attributed. The synergetic effects of carbon networks and surface structures are responsible for the high EMI shielding performance; various reflections inside the interconnected networks may also help in improving their EMI shielding performance.

Application of Contrast-enhanced Ultrasound and Bosniak Classification to the Diagnosis of Cystic Renal Masses.

BACKGROUND: The Bosniak classification system based on contrast-enhanced computed tomography (CECT) is commonly used for the differential diagnosis of cystic renal masses. Contrastenhanced ultrasound (CEUS) is a relatively novel technique, which has gradually played an important role in the diagnosis of cystic renal cell carcinoma (CRCC) due to its safety and lowest price. OBJECTIVE: The aim of the study is to investigate the application value of CEUS and Bosniak classification into the diagnosis of cystic renal masses. METHODS: 32 cystic masses from January 2018 to December 2019 were selected. The images of conventional ultrasound (US), CEUS and CECT from subjects confirmed by surgical pathology were retrospectively analyzed. The Bosniak classification system of cystic renal masses was implemented using CEUS and CECT, and the diagnostic ability was compared. RESULTS: For the 32 cystic masses, postoperative pathology confirmed 11 cases of multilocular CRCC, 15 cases of clear cell carcinoma with hemorrhage, necrosis and cystic degeneration, 5 cases of renal cysts, and 1 case of renal tuberculosis. The Bosniak classification based on CEUS was higher than that based on CECT, and the difference was statistically significant (P = .024). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CEUS were comparable to CECT. There was no significant difference observed in the diagnosis of CRCC (P >.05). CONCLUSION: CEUS combined with Bosniak classification greatly improves the diagnosis of CRCC. CEUS shows a comparable diagnostic ability to CECT. In daily clinical routine, patients who require multiple examinations and present contraindications for CECT can particularly benefit from CEUS.

Contrast-enhanced Ultrasound for Diagnosis of Renal Cystic Mass.

BACKGROUND: Cystic Renal Cell Carcinoma (CRCC) is often difficult to differentiate from complex cysts with sonographic manifestations of renal carcinoma. Contrast-Enhanced Ultrasound (CEUS) is a new technology, and its clinical utility in the diagnosis of renal cystic mass has not been established. OBJECTIVE: The objective of this study is to analyze the characteristics of CEUS of renal cystic masses and to explore the clinical significance and value of CEUS in the diagnosis of CRCC. METHODS: This study was a retrospective study. A total of 32 cystic masses from January 2018 to December 2019 were selected. The images of conventional Ultrasound (US) and CEUS were confirmed via surgical pathology. Routine US was used to observe the location, shape, size, boundary, cyst wall, internal echo, and blood supply of each cystic mass. CEUS observed contrast enhancement of the cyst wall, cystic septa, and solid nodules of cystic masses. RESULTS: There were 26 cases of CRCC, 5 cases of renal cysts, and 1 case of renal tuberculosis. The enhancement pattern, degree of enhancement, and pseudocapsular sign by CEUS in benign and malignant masses had statistically significant differences (P<.05). In the diagnosis of CRCC, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 92.3%, 83.3%, 90.6%, 96.0%, and 71.4% for CEUS; 57.6%, 66.7%, 59.3%, 88.2%, and 26.7% for conventional US, respectively. CEUS had a higher sensitivity and accuracy than the conventional US (P<.05), although the diagnostic specificity, positive predictive value and negative predictive value of the two methods were not significantly different (P>.05). CONCLUSION: CEUS is more accurate in the diagnosis of renal cystic masses, and it can be used as an effective imaging method.

NapM enhances the survival of Mycobacterium tuberculosis under stress and in macrophages.

Hostile environmental cues cause Mycobacterium tuberculosis to enter a state of slow growth for survival. However, the underlying regulatory mechanism remains unclear. DnaA is essential for DNA replication initiation and represents an efficient target for growth regulation in bacteria. Here, we show that the nucleoid-associated protein NapM is a DnaA antagonist, protecting M. tuberculosis from stress-mediated killing. NapM can be induced by diverse stressful signals. It binds to DnaA to inhibit both its DNA replication origin-binding and ATP hydrolysis activity. As a DnaA antagonist, NapM inhibits the mycobacterial DNA synthesis in vitro and in vivo in M. tuberculosis. Furthermore, we show that NapM contributes to the survival of M. tuberculosis under stress and within macrophages during infection. Our findings provide a previously unidentified mechanism of mycobacterial survival under stress and also suggest NapM as a potential drug target for tuberculosis control.

NapM, a new nucleoid-associated protein, broadly regulates gene expression and affects mycobacterial resistance to anti-tuberculosis drugs.

Nucleoid-associated proteins (NAPs) play important roles in the global organization of bacterial chromosomes. However, potential NAPs and their functions are barely characterized in mycobacteria. In this study, NapM, an alkaline protein, functions as a new NAP. NapM is conserved in all of the sequenced mycobacterial genomes, and can recognize DNA in a length-dependent but sequence-independent manner. It prefers AT-rich DNA and binds to the major groove. NapM possesses a clear DNA-bridging function, and can protect DNA from DNase I digestion. NapM globally regulates the expression of more than 150 genes and the resistance of Mycobacterium smegmatis to two anti-tuberculosis drugs, namely, rifampicin and ethambutol. An ABC transporter operon was found to be specifically responsible for the napM-dependent ethambutol resistance of M. smegmatis. NapM also presents a similar regulation of anti-tuberculosis drug resistance in M. tuberculosis. These results suggest that NapM is a new member of the mycobacterial NAP family. Our findings expand the range of identified NAPs and improve the understanding on the relationship between NAPs with antibiotic resistance in mycobacteria.