Cloning and expression of pineapple sucrosephosphate synthase gene during fruit development

A 1132-base pairs (bp) polymerase-chain-reaction product of sucrose-phosphate synthase (SPS) (EC 2.3.1.14) from pineapple (Ananas comosus cv. Comte de paris) fruit was cloned and nominated as Ac- SPS1. The sequence encodes a putative 377 amino acids protein containing two serine conserved features that had been found in other plant SPS genes: the presence of a 14-3-3 protein special binding domain and an activated site of osmosis stress, which can been activated by phosphorylation and dephosphorylation. The Neighbour-joining tree revealed that Ac-SPS1 belonged to the first kind of sucrose phosphate synthase gene. The results indicated that, the Ac-SPS1 expression was low in the earlier period of fruit growth, then, increasing from 20 days after anthesis and gradually a falling on 40 days, reached the peak with the highest value around 70 days. The SPS activity and sucrose content reached their maximum 80 days after anthesis. It proved that the  accumulation of sucrose was correlated with SPS activity and mRNA content and it maximally occurred at 10 d after SPS mRNA and activity had reached its maxima. These results indicated that Ac-SPS1 gene played a key role in sucrose accumulation during the pineapple fruit development and transcriptional activation with increase in Ac- SPS1 expression might be important regulatory events of sugar during pineapple fruit maturation.Key words: Pineapple fruit, sucrose phosphate synthase, gene cloning, expression

Where is VALDO? VAscular Lesions Detection and segmentatiOn challenge at MICCAI 2021

Imaging markers of cerebral small vessel disease provide valuable information on brain health, but their manual assessment is time-consuming and hampered by substantial intra- and interrater variability. Automated rating may benefit biomedical research, as well as clinical assessment, but diagnostic reliability of existing algorithms is unknown. Here, we present the results of the VAscular Lesions DetectiOn and Segmentation (Where is VALDO?) challenge that was run as a satellite event at the international conference on Medical Image Computing and Computer Aided Intervention (MICCAI) 2021. This challenge aimed to promote the development of methods for automated detection and segmentation of small and sparse imaging markers of cerebral small vessel disease, namely enlarged perivascular spaces (EPVS) (Task 1), cerebral microbleeds (Task 2) and lacunes of presumed vascular origin (Task 3) while leveraging weak and noisy labels. Overall, 12 teams participated in the challenge proposing solutions for one or more tasks (4 for Task 1-EPVS, 9 for Task 2-Microbleeds and 6 for Task 3-Lacunes). Multi-cohort data was used in both training and evaluation. Results showed a large variability in performance both across teams and across tasks, with promising results notably for Task 1-EPVS and Task 2-Microbleeds and not practically useful results yet for Task 3-Lacunes. It also highlighted the performance inconsistency across cases that may deter use at an individual level, while still proving useful at a population level

The Debt-contracting Value of Accounting Numbers, Renegotiation, and Investment Efficiency

This study investigates the impact of the debt-contracting value (DCV) of borrowers' accounting information on the likelihood of private debt renegotiation and the implication of renegotiation for borrowing firms' investment efficiency. Accounting numbers, as contractible signals, are broadly used in formal debt contracting. DCV captures the inherent ability of firms' accounting numbers to predict future credit quality. Building on incomplete contract theory, I hypothesize that a lower DCV of a borrower's accounting numbers creates ex post incentives for both parties to renegotiate the terms of the initial contract, leading to a higher probability of renegotiation. During the renegotiation, the lenders can extract partial gains from the borrowers' investment according to their relative bargaining power. Anticipating the high-probability of renegotiation reduces the ex ante investment incentives of borrowers, inducing underinvestment. Using a sample of 3,720 private debt contracts, I find that 76% of the contracts are renegotiated before maturity, and 75% of renegotiation cases are related to the changes of accounting-based contractual terms. I further find that firms with a higher DCV have a lower probability of renegotiation and less underinvestment. Moreover, the impact of DCV on investment increases with lenders' relative bargaining power.Ph

Health Insurer Bargaining Power and Firms’ Incentives to Manage Earnings: Evidence From an Economic Shock

Health insurance premiums account for a significant portion of the cost base of U.S. corporations. A recent study finds that health insurance premiums increase for firms that experience positive profit shocks, suggesting that the U.S. health insurance market is not perfectly competitive. Motivated by this finding and the economic importance of health insurance premiums, this is the first study to examine firms’ earnings management incentives in the face of insurance carriers with strong bargaining power. We use an innovative data set for a large sample of U.S. firms with detailed information on insurance premiums and insurance plan characteristics. Using an economic shock to insurance firms’ bargaining power and difference-in-differences tests, we find that firms manage their reported earnings downward when insurance providers have strong bargaining power. We further show that this effect is more pronounced in settings in which there are ex ante reasons to expect stronger incentives to manage earnings downward. We also provide preliminary evidence suggesting that downward earnings management has the intended effect of mitigating future increases in health insurance premiums. Our analyses highlight an inefficient health insurance market as an important determinant of firms’ financial reporting choices