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To improve the coverage in bottom-up proteomics, S-aminoethylation of cysteine residues (AE-Cys) was carried out with 2-bromoethylamine, followed by cleavage with lysyl endopeptidase (Lys-C) or Lys-C/trypsin. A model study with bovine serum albumin showed that the C-terminal side of AE-Cys was successfully cleaved by Lys-C. The frequency of side reactions at amino acids other than Cys was less than that in the case of carbamidomethylation of Cys with iodoacetamide. Proteomic analysis of A549 cell extracts in the data-dependent acquisition mode after AE-Cys modification afforded a greater number of identified protein groups, especially membrane proteins. In addition, label-free quantification of proteins in mouse nonsmall cell lung cancer (NSCLC) tissue in the data-independent acquisition mode after AE-Cys modification showed improved NSCLC pathway coverage and greater reproducibility. Furthermore, the AE-Cys method could identify an epidermal growth factor receptor peptide containing the T790 M mutation site, a well-established lung-cancer-related mutation site that has evaded conventional bottom-up methods. Finally, AE-Cys was found to fully mimic Lys in terms of collision-induced dissociation fragmentation, ion mobility separation, and cleavage by Lys-C/trypsin, except for sulfoxide formation during sample preparation., To improve the coverage in bottom-up proteomics, S-aminoethylation of cysteine residues (AE-Cys) was carried out with 2-bromoethylamine, followed by cleavage with lysyl endopeptidase (Lys-C) or Lys-C/trypsin. A model study with bovine serum albumin showed that the C-terminal side of AE-Cys was successfully cleaved by Lys-C. The frequency of side reactions at amino acids other than Cys was less than that in the case of carbamidomethylation of Cys with iodoacetamide. Proteomic analysis of A549 cell extracts in the data-dependent acquisition mode after AE-Cys modification afforded a greater number of identified protein groups, especially membrane proteins. In addition, label-free quantification of proteins in mouse nonsmall cell lung cancer (NSCLC) tissue in the data-independent acquisition mode after AE-Cys modification showed improved NSCLC pathway coverage and greater reproducibility. Furthermore, the AE-Cys method could identify an epidermal growth factor receptor peptide containing the T790 M mutation site, a well-established lung-cancer-related mutation site that has evaded conventional bottom-up methods. Finally, AE-Cys was found to fully mimic Lys in terms of collision-induced dissociation fragmentation, ion mobility separation, and cleavage by Lys-C/trypsin, except for sulfoxide formation during sample preparation.

In recent decades, there’s been a growing trend in universities to interact with non-academic partners. The term ‘academic engagement’ describes the interactions and activities between academia and these partners, including industries and governmental organizations. Commercialization activities that involve patenting, licensing, and establishing spin-out companies are common for the interactions between university and industry, or so-called University-Industry (U-I) interactions. Examples of University-Government (U-G) interactions previously identified in the literature include advising, school projects, and public exhibitions. Among different U-G interactions, University-Regulator (U-R) interactions refer to those relevant to policymaking and granting legal approval. This study focused on the ones between universities and drug regulatory authorities. U-R interactions in drug development appealed to us for a couple of reasons. Compared to other fields of expertise, U-R interactions in drug development are more common and the bond between academia and regulatory authorities is fairly tight. Moreover, further insights on U-R interactions in drug development were expected to optimize the drug development procedure. We conducted an interview study to understand the context of U-R interactions in drug development and regulations, motivations for academics and regulators to interact with each other, potential barriers in these interactions, and suggestions perceived by both parties to improve the situation. In total, 21 experts from Dutch academia and Dutch and European regulatory authorities participated in the interviews. The online interviews were recorded and transcribed. The transcripts were later analyzed qualitatively to answer our research questions. This study revealed some U-R interactions in drug development that overlapped with U-I and general U-G interactions. People-based activities such as giving lectures and advising were examples of these mutual interact

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a ‘one-step operation’. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars ‘Smooth Cayenne’ and ‘Queen’ exhibited ancient and recent admixture, while ‘Singapore Spanish’ supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a ‘one-step operation’. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars ‘Smooth Cayenne’ and ‘Queen’ exhibited ancient and recent admixture, while ‘Singapore Spanish’ supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a ‘one-step operation’. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars ‘Smooth Cayenne’ and ‘Queen’ exhibited ancient and recent admixture, while ‘Singapore Spanish’ supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

Domestication of clonally propagated crops such as pineapple from South America was hypothesized to be a 'one-step operation'. We sequenced the genome of Ananas comosus var. bracteatus CB5 and assembled 513 Mb into 25 chromosomes with 29,412 genes. Comparison of the genomes of CB5, F153 and MD2 elucidated the genomic basis of fiber production, color formation, sugar accumulation and fruit maturation. We also resequenced 89 Ananas genomes. Cultivars 'Smooth Cayenne' and 'Queen' exhibited ancient and recent admixture, while 'Singapore Spanish' supported a one-step operation of domestication. We identified 25 selective sweeps, including a strong sweep containing a pair of tandemly duplicated bromelain inhibitors. Four candidate genes for self-incompatibility were linked in F153, but were not functional in self-compatible CB5. Our findings support the coexistence of sexual recombination and a one-step operation in the domestication of clonally propagated crops. This work guides the exploration of sexual and asexual domestication trajectories in other clonally propagated crops.

Ling-Bo Liang, Xia Zhu, Li-Bo Yan, Ling-Yao Du, Cong Liu, Li-Yu Chen, Juan Liao, Hong Tang Center of Infectious Disease, West China Hospital, West China School of Medicine, and State Key Laboratory of Biotherapy, Sichuan University, Chengdu, People’s Republic of China Objective: To explore the predictive value of serum hepatitis B surface antigen (HBsAg) titer and transient elastography in screening for insignificant fibrosis in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients. Methods: We conducted a cross-sectional study of eligible patients treated from March 2012 to May 2013 at the West China Hospital of Sichuan University. Eligible patients underwent liver transient elastography and liver biopsy. We assessed the serum HBsAg level, serum hepatitis B virus (HBV) deoxyribonucleic acid (DNA) level, HBV genotypes, liver stiffness measurement (LSM) values by transient elastography, and histological fibrosis staging by METAVIR classification. Results: A total of 129 consecutive patients were recruited. The LSM value (P<0.001, odds ratio 14.67, 95% CI 0.158–0.551) and log10HBsAg (P=0.045, odds ratio 4.03, 95% CI 0.136–0.976) correlated with a liver fibrosis score

The purification of human adipose-derived stem cells (hADSCs) from human adipose tissue cells (stromal vascular fraction) was investigated using membrane filtration through poly(lactide-co-glycolic acid)/silk screen hybrid membranes. Membrane filtration methods are attractive in regenerative medicine because they reduce the time required to purify hADSCs (i.e., less than 30 min) compared with conventional culture methods, which require 5–12 days. hADSCs expressing the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the permeation solution from the hybrid membranes. Expression of the surface markers CD44, CD73, and CD99 on the cells in the permeation solution from the hybrid membranes, which were obtained using 18 mL of feed solution containing 50 × 104 cells, was statistically significantly higher than that of the primary adipose tissue cells, indicating that the hADSCs can be purified in the permeation solution by the membrane filtration method. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the permeation solution, whereas CD34+ cells could not be purified by the conventional culture method. The hADSCs in the permeation solution demonstrated a superior capacity for osteogenic differentiation based on their alkali phosphatase activity, their osterix gene expression, and the results of mineralization analysis by Alizarin Red S and von Kossa staining compared with the cells from the suspension of human adipose tissue. These results suggest that the hADSCs capable of osteogenic differentiation preferentially permeate through the hybrid membranes.

The purification of human adipose-derived stem cells (hADSCs) from human adipose tissue cells (stromal vascular fraction) was investigated using membrane filtration through poly(lactide-co-glycolic acid)/silk screen hybrid membranes. Membrane filtration methods are attractive in regenerative medicine because they reduce the time required to purify hADSCs (i.e., less than 30 min) compared with conventional culture methods, which require 5–12 days. hADSCs expressing the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the permeation solution from the hybrid membranes. Expression of the surface markers CD44, CD73, and CD99 on the cells in the permeation solution from the hybrid membranes, which were obtained using 18 mL of feed solution containing 50 × 104 cells, was statistically significantly higher than that of the primary adipose tissue cells, indicating that the hADSCs can be purified in the permeation solution by the membrane filtration method. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the permeation solution, whereas CD34+ cells could not be purified by the conventional culture method. The hADSCs in the permeation solution demonstrated a superior capacity for osteogenic differentiation based on their alkali phosphatase activity, their osterix gene expression, and the results of mineralization analysis by Alizarin Red S and von Kossa staining compared with the cells from the suspension of human adipose tissue. These results suggest that the hADSCs capable of osteogenic differentiation preferentially permeate through the hybrid membranes.

This thesis comprises an empirical review of the cost asymmetric behaviour and two empirical studies on cost structures in family-type organisations. In this thesis, I first introduce cost asymmetric behaviour and review the relevant literature in Chapter 2. Scholars refer to the phenomenon of cost asymmetric behaviour as “cost stickiness”. This chapter includes the evidence for cost stickiness and the significant critical determinants that impact the degree of cost stickiness. In two empirical studies in Chapters 3 and 4, I explore the cost stickiness in firms based on the unique characteristics and culture of a family type of organisational structure. Because of greater alignment of owner-manager incentives, higher accounting conservatism, and being more risk-averse, research on family firms has shown that founding family firms have fewer agency problems between owners and managers than non-family firms (Shleifer and Vishny 1997; Villalonga and Amit 2006; Anderson and Reeb 2003b; Chen et al. 2010). This context provides an interesting case for examining how managerial choices in family firms can adjust resources to influence family firms’ cost structure and stickiness. Chapter 3 investigates the effects of different agency problems on selling general and administrative (SG&A) cost stickiness in family and non-family firms based on the unique characteristics and culture of family firms. I use four measures of agency problems arising from CEOs’ incentives, including free cash flow, CEO tenure of the first three years, CEO tenure of the final year, and the percentage of fixed pay in the CEO’s total compensation. In additional tests, I examine the role of corporate governance in moderating to mitigate the effect of the agency problem on SG&A asymmetrical cost. As managers in family firms face different incentives, I conjecture that they are more likely to avoid rapidly increasing or slowly decreasing SG&A costs when sales grow or decline, respectively, compared with n

This thesis comprises an empirical review of the cost asymmetric behaviour and two empirical studies on cost structures in family-type organisations. In this thesis, I first introduce cost asymmetric behaviour and review the relevant literature in Chapter 2. Scholars refer to the phenomenon of cost asymmetric behaviour as “cost stickiness”. This chapter includes the evidence for cost stickiness and the significant critical determinants that impact the degree of cost stickiness. In two empirical studies in Chapters 3 and 4, I explore the cost stickiness in firms based on the unique characteristics and culture of a family type of organisational structure. Because of greater alignment of owner-manager incentives, higher accounting conservatism, and being more risk-averse, research on family firms has shown that founding family firms have fewer agency problems between owners and managers than non-family firms (Shleifer and Vishny 1997; Villalonga and Amit 2006; Anderson and Reeb 2003b; Chen et al. 2010). This context provides an interesting case for examining how managerial choices in family firms can adjust resources to influence family firms’ cost structure and stickiness. Chapter 3 investigates the effects of different agency problems on selling general and administrative (SG&A) cost stickiness in family and non-family firms based on the unique characteristics and culture of family firms. I use four measures of agency problems arising from CEOs’ incentives, including free cash flow, CEO tenure of the first three years, CEO tenure of the final year, and the percentage of fixed pay in the CEO’s total compensation. In additional tests, I examine the role of corporate governance in moderating to mitigate the effect of the agency problem on SG&A asymmetrical cost. As managers in family firms face different incentives, I conjecture that they are more likely to avoid rapidly increasing or slowly decreasing SG&A costs when sales grow or decline, respectively, compared with n

This thesis comprises an empirical review of the cost asymmetric behaviour and two empirical studies on cost structures in family-type organisations. In this thesis, I first introduce cost asymmetric behaviour and review the relevant literature in Chapter 2. Scholars refer to the phenomenon of cost asymmetric behaviour as “cost stickiness”. This chapter includes the evidence for cost stickiness and the significant critical determinants that impact the degree of cost stickiness. In two empirical studies in Chapters 3 and 4, I explore the cost stickiness in firms based on the unique characteristics and culture of a family type of organisational structure. Because of greater alignment of owner-manager incentives, higher accounting conservatism, and being more risk-averse, research on family firms has shown that founding family firms have fewer agency problems between owners and managers than non-family firms (Shleifer and Vishny 1997; Villalonga and Amit 2006; Anderson and Reeb 2003b; Chen et al. 2010). This context provides an interesting case for examining how managerial choices in family firms can adjust resources to influence family firms’ cost structure and stickiness. Chapter 3 investigates the effects of different agency problems on selling general and administrative (SG&A) cost stickiness in family and non-family firms based on the unique characteristics and culture of family firms. I use four measures of agency problems arising from CEOs’ incentives, including free cash flow, CEO tenure of the first three years, CEO tenure of the final year, and the percentage of fixed pay in the CEO’s total compensation. In additional tests, I examine the role of corporate governance in moderating to mitigate the effect of the agency problem on SG&A asymmetrical cost. As managers in family firms face different incentives, I conjecture that they are more likely to avoid rapidly increasing or slowly decreasing SG&A costs when sales grow or decline, respectively, compared with n

This thesis comprises an empirical review of the cost asymmetric behaviour and two empirical studies on cost structures in family-type organisations. In this thesis, I first introduce cost asymmetric behaviour and review the relevant literature in Chapter 2. Scholars refer to the phenomenon of cost asymmetric behaviour as “cost stickiness”. This chapter includes the evidence for cost stickiness and the significant critical determinants that impact the degree of cost stickiness. In two empirical studies in Chapters 3 and 4, I explore the cost stickiness in firms based on the unique characteristics and culture of a family type of organisational structure. Because of greater alignment of owner-manager incentives, higher accounting conservatism, and being more risk-averse, research on family firms has shown that founding family firms have fewer agency problems between owners and managers than non-family firms (Shleifer and Vishny 1997; Villalonga and Amit 2006; Anderson and Reeb 2003b; Chen et al. 2010). This context provides an interesting case for examining how managerial choices in family firms can adjust resources to influence family firms’ cost structure and stickiness. Chapter 3 investigates the effects of different agency problems on selling general and administrative (SG&A) cost stickiness in family and non-family firms based on the unique characteristics and culture of family firms. I use four measures of agency problems arising from CEOs’ incentives, including free cash flow, CEO tenure of the first three years, CEO tenure of the final year, and the percentage of fixed pay in the CEO’s total compensation. In additional tests, I examine the role of corporate governance in moderating to mitigate the effect of the agency problem on SG&A asymmetrical cost. As managers in family firms face different incentives, I conjecture that they are more likely to avoid rapidly increasing or slowly decreasing SG&A costs when sales grow or decline, respectively, compared with n