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Replacing the steam cracking process with oxidative dehydrogenation for ethylene production offers potential energy and environmental benefits. To evaluate these possibilities, a study combining conceptual process design, techno-economic analysis, and life cycle assessments of the oxidative dehydrogenation of ethane (ODHE) for producing ethylene at an industrial scale is performed. For comparison, the conventional steam cracking process of ethane is also simulated and optimized. The techno-economic analysis results for ODHE with a boron-containing zeolite chabazite (B-CHA) catalyst, as developed in our group, demonstrate that it is economically competitive ($790 per t ethylene production) compared to the steam cracking process ($832 per t ethylene production). However, a "cradle-to-gate" life-cycle assessment shows that the ODHE process emits more greenhouse gases (2.42 kg CO2 equiv. per kg ethylene) compared to the steam cracking counterpart (1.34 kg CO2 equiv. per kg ethylene). The discrepancy between the initial hypothesis and the results arises from the significant refrigerant input required by the ODHE process to recover ethylene from byproducts such as CO, CH4, and unreacted oxygen and ethane. Further scenario analysis reveals that plausible improvements in the C2H6 conversion per pass, the selectivity to ethylene and the ratio of ethane to oxygen in the current ODHE process could render it both economically and environmentally viable as a replacement for the steam cracking process. [ABSTRACT FROM AUTHOR]

BackgroundBased on the ovarian-adnexal reporting and data system (O-RADS), we constructed a nomogram model to predict the malignancy potential of adnexal masses with sophisticated ultrasound morphology.MethodsIn a multicenter retrospective study, a total of 430 subjects with masses were collected in the adnexal region through an electronic medical record system at the Fourth Hospital of Harbin Medical University during the period of January 2019–April 2023. A total of 157 subjects were included in the exception validation cohort from Harbin Medical University Tumor Hospital. The pathological tumor findings were invoked as the gold standard to classify the subjects into benign and malignant groups. All patients were randomly allocated to the validation set and training set in a ratio of 7:3. A stepwise regression analysis was utilized for filtering variables. Logistic regression was conducted to construct a nomogram prediction model, which was further validated in the training set. The forest plot, C-index, calibration curve, and clinical decision curve were utilized to verify the model and assess its accuracy and validity, which were further compared with existing adnexal lesion models (O-RADS US) and assessments of different types of neoplasia in the adnexa (ADNEX).ResultsFour predictors as independent risk factors for malignancy were followed in the preparation of the diagnostic model: O-RADS classification, HE4 level, acoustic shadow, and protrusion blood flow score (all p

There are several surgical strategies which have been proposed to treat the osteoporotic patient with vertebral fracture, ranging from vertebral body cement augmentation, percutaneous/mini-open short segment pedicle screw fixation, and cortical bone trajectory screw to kyphotic deformity correction surgery. Minimally invasive spine surgery has the potential benefits of faster recovery, reduced blood loss, less postoperative wound pain, lower infection risk, and shorter length of hospital stay. Novel surgical techniques such as percutaneous instrumentation fixation, cortical bone trajectory technique, screw cement augmentation, and vertebral body augmentation are developed. However, various complications have been reported, including pedicle fracture, instrumentation loosening, adjacent-level disc degeneration with herniation, and progressive junctional kyphosis. The purpose of this review was to outline various advancements in minimally invasive spinal surgery for patients with osteoporosis. Minimally invasive surgical techniques for fixation including percutaneous instrumentation, cortical bone trajectory technique, screw cement augmentation, and vertebral body augmentation have benefited patient with osteoporosis. Studies and discussions about short-segment pedicle screw fixation (one level above and below the fracture level) have shown that it provides enough stability for thoracolumbar burst fractures. There are also complications, including cement embolism, adjacent vertebral fracture, neuraxial anesthesia, and infection, which have been observed with the above technique. With the advancement of instrument and technique, the complication rate decreased in recent studies. Minimally invasive fixation still has many advantages for patients with osteoporosis. Many of these studies and strategies only have evidence from biomechanical and cadaveric studies and require further clinical trials to establish their clinical efficacy.

Retaining a waterproof coal pillar is an important measure to defend against water inrush accidents in mining areas and guarantee the safe mining of the next working face. In this paper, the mechanical model of the coal pillar is established and the calculation formula of the waterproof coal pillar width is derived. Then, the development of the water-conducting fracture zone of the overlying rock layer under different coal pillar widths is analyzed using numerical simulation and finally, the integrity of the coal pillar is detected using the geophysical survey method. The main conclusions are as follows: (1) According to the mechanical failure characteristics of the coal pillar, it can be divided into the plastic zone, elastic zone, and water pressure damage zone. The mechanical calculation model for each zone was established, and the formula for calculating the width of the waterproof coal pillar was obtained. (2) Numerical simulation was employed to investigate the development condition of the water conducting fracture zone in the overlying rock strata under the actual width of the waterproof coal pillar; the simulation results indicated that the water conducting fracture zone of two working faces was not connected, which can effectively prevent the accumulation of water in the 2303 goaf. (3) On-site geophysical surveys determined that the influence of water-logged goaf on the coal pillar is between 5 to 15 m; the integrity of the waterproof coal pillar is good, which effectively prevents water accumulation in the previous working face goaf and ensures safe mining in the next working face.

In this article, I compare constitutional and administrative models in terms of their implications for the EU legal order’s interaction with other legal regimes. I aim to make a twofold argument on the implications of the EU’s constitutional self-image to the world political order. First, as the CJEU adopts an identity-centred strong constitutionalist position on the Union’s external relations, it implicitly frames the EU legal order’s interaction with other legal regimes as in a federated order. Yet the strong political implications of federation are likely to bring about more inter-regime conflicts and provoke reactions from Member States. Second, I provide a critique of the administrative model in the light of GAL’s intervention in inter-regime relations, suggesting a post-identity constitutional alternative in times of crisis. Freed from the value-laden concept of constitutional identity, but without de-constitutionalizing itself, the EU can have the benefits of both the constitutional and administrative models by moving towards a weak-form constitutional order. In the event, the debate, as to whether to conduct the EU’s external relations according to the constitutional or the administrative model, is misconceived.

Abstract Background Chikungunya fever is a pandemic disease caused by the mosquito-borne Chikungunya virus (CHIKV). E1 glycoprotein mediation of viral membrane fusion during CHIKV infection is a crucial step in the release of viral genome into the host cytoplasm for replication. How the E1 structure determines membrane fusion and whether other CHIKV structural proteins participate in E1 fusion activity remain largely unexplored. Methods A bicistronic baculovirus expression system to produce recombinant baculoviruses for cell-based assay was used. Sf21 insect cells infected by recombinant baculoviruses bearing wild type or single-amino-acid substitution of CHIKV E1 and EGFP (enhanced green fluorescence protein) were employed to investigate the roles of four E1 amino acid residues (G91, V178, A226, and H230) in membrane fusion activity. Results Western blot analysis revealed that the E1 expression level and surface features in wild type and mutant substituted cells were similar. However, cell fusion assay found that those cells infected by CHIKV E1-H230A mutant baculovirus showed little fusion activity, and those bearing CHIKV E1-G91D mutant completely lost the ability to induce cell-cell fusion. Cells infected by recombinant baculoviruses of CHIKV E1-A226V and E1-V178A mutants exhibited the same membrane fusion capability as wild type. Although the E1 expression level of cells bearing monomeric-E1-based constructs (expressing E1 only) was greater than that of cells bearing 26S-based constructs (expressing all structural proteins), the sizes of syncytial cells induced by infection of baculoviruses containing 26S-based constructs were larger than those from infections having monomeric-E1 constructs, suggesting that other viral structure proteins participate or regulate E1 fusion activity. Furthermore, membrane fusion in cells infected by baculovirus bearing the A226V mutation constructs exhibited increased cholesterol-dependences and lower pH thresholds. Cells bearing the V178A mutation exhibited a slight decrease in cholesterol-dependence and a higher-pH threshold for fusion. Conclusions Cells expressing amino acid substitutions of conserved protein E1 residues of E1-G91 and E1-H230 lost most of the CHIKV E1-mediated membrane fusion activity. Cells expressing mutations of less-conserved amino acids, E1-V178A and E1-A226V, retained membrane fusion activity to levels similar to those expressing wild type E1, but their fusion properties of pH threshold and cholesterol dependence were slightly altered.

Abstract Introduction Angiomyolipoma is a common benign renal tumor composed of thick-walled blood vessels, smooth muscle, and adipose tissue. It may be found incidentally during workup for suspected renal disease. Although angiomyolipoma may present as a palpable, tender renal mass with flank pain and gross or microscopic hematuria, many patients are asymptomatic. Erythrocytosis is an unusual presentation, and malignant transformation may be suspected. This report describes a rare case of a woman diagnosed with renal angiomyolipoma and polycythemia vera. The report discusses the differential diagnosis using erythropoietin, erythropoietin-receptor and Janus kinase 2. Case presentation A 79-year-old Chinese woman was diagnosed with erythrocytosis according to World Health Organization criteria. An upper left renal pole angiomyolipoma was successfully ablated after multiple phlebotomy treatments. Red cell count immediately returned to normal, but gradually increased after 4 months. Polycythemia vera was finally diagnosed by positive mutation of Janus kinase 2 and negative erythropoietin protein expression. Her clinical symptoms improved with regular phlebotomy and hydroxyurea treatment. Conclusion Concurrent occurence of angiomyolipoma and polycythemia vera is rare. Polycythemia vera can be easily missed. Polycythemia vera can be confirmed with high specificity and sensitivity by the acquired somatic mutation. Surgical intervention for this renal tumor should be avoided unless malignancy or renal cell carcinoma is suspected or to prevent spontaneous rupture of larger tumors.

The effects of chymosin on the physicochemical and hydrolysis characteristics of casein micelles and individual caseins were investigated. Adding 0.03 units of chymosin/mL led to the casein micelles in skim milk coagulating after a 3 h incubation period at 30 °C. SDS-PAGE investigation showed that β-CN, κ-CN, α s -CN, and a portion of β-lactoglobulin (β-LG) in the milk supernatant fraction (MSF) were precipitated into the milk pellet fraction (MPF). The mean particle size of the MSF with chymosin decreased from 254.4 nm to 179.2 nm after a 3 h incubation period. Mass spectrometry and SDS-PAGE analysis suggested that chymosin hydrolyzed individual β-CN, κ-CN, and α s -CN, but not β-LG. Chymosin hydrolysis led to a decrease in the molecular weights of the hydrolyzed β-CN, κ-CN, and α s -CN. Particle size analysis indicated that there was no difference in the particle size distribution of hydrolyzed β-CN and α s -CN. Moreover, our outcomes demonstrated that the hydrolysis of κ-CN by chymosin occurs before that of β-CN and α s -CN.

Black soybeans are commonly consumed as health foods and used in traditional Chinese medicine, but they are rarely cultivated as edible sprouts. During germination, the composition of seeds undergoes distinct changes that cause variations in bioactivities. In this study, the water-soluble black soybean polysaccharide (BSPS) was isolated from sprouts harvested at two-day intervals during the first week of seedling growth. The chromatographic profiles of the BSPS in ungerminated seeds showed fraction 1 (F1, about 64kDa) and fraction 2 (F2, <1kDa) that degraded during germination. The polysaccharide in F1 fraction of ungerminated seeds was covalently associated with the protein and mainly contained arabinose, galactose, glucose, and galacturonic acid at various levels during germination. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) scavenging activities and the reducing power of F1 were highest on the seventh day of germination. The phenolic and flavonoid content significantly increased after the fifth day of germination, suggesting that these ingredients also contributed to the antioxidant activities. During long-term germination, the polysaccharide-protein conjugate in the F1 fraction with enhanced antioxidant activities is regarded as a potential natural antioxidant for the development of functional foods., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The physicochemical properties of Chinese soft-shell turtle egg were characterized for functional use in the food industry. The egg yolk of un-fertilized soft-shell turtle eggs was separated and fractionated into granules and plasma. Then, the egg yolk, albumen, granules, and plasma were freeze-dried for further analysis. Results showed that the Chinese soft-shell turtle egg typically comprised 50% egg yolk, 34% albumen, and 16% shell in average. The egg yolk composed of 61% granules and 39% plasma. The granules contained most of the protein, while the plasma contained most of the lipid in egg yolk. The albumen contained about 26% ash on a dry weight basis. Lysozyme was the major component in turtle egg albumen. The protein solubility of egg yolk, granules, and plasma was affected by the changes in pH, while that of albumen remains constant. The emulsifying and foaming properties increased when the concentration increased for all samples. Both the yolk and the albumen in turtle egg exhibited better functional properties than those in normal hen egg. These physicochemical and functional properties of Chinese soft-shell turtle egg are fundamental and essential for future study and food applications., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This study investigated the propylene glycol alginate (PGA)-induced coacervation of β-conglycinin (7S), glycinin (11S) and isoflavones in heated soymilk. The addition of 0.9% PGA caused 7S, 11S, daidzein and genistein to coacervate following a 1h incubation period. SDS-PAGE showed that the protein bands corresponding to the 7S α', 7S α, 7S β, 11S A3, and 11S acidic subunits and the 11S basic proteins in the soymilk supernatant fraction (SSF) decreased to 37.7 ± 12.7%, 24.7 ± 3.9%, 4.9 ± 1.8%, 8.5 ± 2.7%, 18.1 ± 1.8% and 6.0 ± 1.6%, respectively. In addition, isoflavones including daidzein and genistein were also coacervated from the SSF into the soymilk pellet fraction (SPF) following incubation with 0.9% PGA for 1h. The amounts of daidzein and genistein in the SSF decreased to 8.6 ± 1.6% and 2.0 ± 1.0%, respectively. HPLC analysis suggested that daidzein and genistein were bound to the 7S and 11S proteins. These results suggested that daidzein and genistein were co-precipitated with the 7S and 11S proteins into the SPF by 0.9% PGA. Our results demonstrated that PGA is a potent coagulant for the coacervation of 7S, 11S, daidzein and genistein., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Sixteen red rice accessions from the southern United States were studied for their physical, milling, pasting, and thermal properties, chemical composition, and starch fine structure relative to cultivated medium- and long-grain rice varieties. All red rice samples were medium-grain, but their physicochemical properties were different from those of Bengal, a cultivated medium-grain rice. Their apparent amylose and crude protein contents were generally higher, and their amylopectin structure consisted of a higher percentage of the shorter branch chains (DP6-24) and a lower percentage of the longer branch chains (DP25-65). Red rice starch pasting and thermal properties were similar to those of Wells, a long-grain rice cultivar. The red rice samples can be classified into two major clusters according to their kernel properties by hierarchical cluster analysis: one cluster with more resemblance to Wells and another cluster with more resemblance to Bengal. Starch structure and kernel physicochemical properties may offer an alternative way of classifying red rice in addition to phenotypic and genetic indices.

Lipase-catalyzed acetylation of cellulose solubilized in the dimethyl sulfoxide/paraformaldehyde organic solvent system was conducted with lipase A12 from Aspergillus niger. The accompanying side cellulase activity of the A. niger lipase partly accounted for the enhanced acetylation mediated by the enzyme, via facilitating the partial degradation of cellulose substrate as evidenced by high-performance size exclusion chromatograph analysis. The enzymatic cellulose acetylation was improved by substrate pretreatment with cellulase or ultrasound by 18 and 14%, respectively, as a result of the reduced substrate molecular size. Additionally, the ultrasound-pretreated cellulose as the starting substrate was beneficial for the cellulose solution preparation due to the increased accessible surface of cellulose as evidenced by its increased sedimentation volume and SEM micrographs. The effect of thermodynamic water activity (aw) on lipase catalytic activity in organic media was also investigated. The maximum acetylation extent (nearly 11 wt %) occurred at aw = 0.52, which was improved by 51% relative to the enzymatic reaction with no control of water activity. The much larger extent to which the lipase-catalyzed cellulose acetylation was enhanced by water activity optimization than by substrate pretreatment further supported the predominant role played by the major lipase activity of the A. niger lipase over its side cellulase activity in catalyzing cellulose ester synthesis in organic media.

The formation of ice during freezing of pasta filata and non-pasta filata Mozzarella cheeses, and the spatial redistribution of water T2 relaxation time and the changes of water self-diffusion coefficient (D) within the unfrozen and frozen-stored cheese samples were observed by nuclear magnetic resonance imaging. Images of water spin number density and water T2 relaxation time were obtained using spin-echo imaging pulse sequence. The water self-diffusion coefficient was measured by pulsed-field gradient spin-echo technique. The ice formation was accompanied by loss of signal intensity in the affected areas of the cheese sample. There was a significant change in T2 and D values of water following freezing-thawing, which can be used to characterize the effect of freezing on cheeses. The D values of the frozen-stored pasta filata Mozzarella cheese samples were higher than those for the unfrozen samples. Such a difference was not observed for the non-pasta filata Mozzarella cheese samples. The T2 distributions of frozen-stored pasta filata Mozzarella cheese samples were narrower, and those for the non-pasta filata Mozzarella cheese samples were broader T2. This may be attributed to the microstructure differences between the two cheeses.

The effects of 1) ripening 2, 7, and 14 d at 7 degrees C before freezing; 2) tempering 7, and 14 d at 7 degrees C after freezing; and 3) frozen storage for 1 and 4 wk at -20 degrees C, on the meltability, stretchability, and microstructure of pasta filata and nonpasta filata Mozzarella cheeses were investigated. Cheeses were cut into 5 x 10 x 7-cm blocks and vacuum-sealed 1 d after manufacture. The results were compared to the corresponding results obtained with unfrozen control samples, aged at 7 degrees C between 2 and 21 d. The changes in physical properties of frozen-stored pasta filata and nonpasta filata Mozzarella cheeses were consistent with critical damage to the cheese microstructure as compared to the unfrozen control samples. Generally, aging before and tempering after freezing resulted in increased meltability of both frozen-stored pasta filata and nonpasta filata Mozzarella cheeses. The stretchability of frozen-stored pasta filata Mozzarella cheese increased during tempering, but that of nonpasta filata Mozzarella cheese decreased during aging and tempering. In most cases, one-week frozen stored pasta filata Mozzarella cheese had higher meltability and stretchability than 4-wk frozen-stored sample. For 1-wk frozen-stored nonpasta filata Mozzarella cheese, the meltability increased but stretchability decreased when it was frozen-stored for 4 wk.

The effect of heat treatments on the meltability of cheese was investigated. Cheddar cheeses of different composition and low-moisture, part-skim Mozzarella cheese were studied at 1, 3, 6, and 12 wk of aging. Cheese samples were heated to 60 degrees C and held for 0, 10, and 20 min before allowing the melted cheese to flow. Mean meltabilities, over all ages, of both Cheddar and Mozzarella cheeses decreased significantly as holding time increased. Meltability of young cheese was scarcely affected by the holding time, in sharp contrast to that of the old cheese where increasing the holding time greatly reduced meltability.

Changes in molecular mobility of water in pasta filata and non-pasta filata Mozzarella cheeses were investigated during the first 10 d of storage using nuclear magnetic resonance (NMR) relaxation techniques. Water in pasta filata Mozzarella was classified into two fractions by spin-spin relaxation times, T21 and T22, and corresponding proton intensities, A1 and A2, representing low and high molecular mobility, respectively. Increase in A1 (and decrease in A2) suggested that, there was a redistribution of water from more- to less-mobile fraction (from T22 to T21 fraction) during the first 10 d of storage. The NMR data did not indicate the two-state behavior of water molecules in non-pasta filata Mozzarella. However, the T2 values of non-pasta filata Mozzarella were comparable to the T21 values of pasta filata Mozzarella indicating that the molecular mobility of water in non-pasta filata Mozzarella is comparable to that of the less mobile water fraction in pasta filata Mozzarella. Generally, T2 and T1 values of pasta filata and non-pasta filata Mozzarella cheeses increased during the 10-d storage. This is believed to be due to structural changes in the protein matrix.

A device especially designed for uniaxial creep test was used in this study. Cheddar cheeses of different fat content were used. To study the linear viscoelastic response of the cheese, temperature of 40 degrees C and stress of 1119.5 Pa were chosen. Tests were carried out at cheese ages of 1, 3, 6, and 12 wk after production date. A six-element Kelvin model was used to model the creep data. Instantaneous slope of the creep curve was defined as the viscoelasticity index. The results showed that the viscoelasticity index based on viscoelastic parameters could be used for predicting cheese meltability. From the analysis of variance test, it was evident that that the viscoelasticity index can be used to distinguish the meltability of Cheddar cheeses of different ages and fat levels.