Sequential group recommendations based on satisfaction and disagreement scores

Recently, group recommendations have gained much attention. Nevertheless, most approaches consider only one round of recommendations. However, in a real-life scenario, it is expected that the history of previous recommendations is exploited to tailor the recommendations towards meeting the needs of the group members. Such history should include not only which items the system suggested, but also the reaction of the members to these items. This work introduces the problem of sequential group recommendations, by exploiting the concept of satisfaction and disagreement. Satisfaction describes how well the group received the suggested items. Disagreement describes the satisfaction bias among the group members. We utilize these concepts in three new aggregation methods, SDAA, SIAA and Average+, designed to address the specific challenges introduced by sequential group recommendations. We experimentally show the effectiveness of our methods using big real datasets for both stable and ephemeral groups.

Placental Transfusion, Timing of Plastic Wrap or Bag Placement, and Preterm Neonates

Objective Compare delivery room practices and outcomes of infants born at less than 32 weeks' gestation or less than 1,500 g who have plastic wrap/bag placement simultaneously during placental transfusion to those receiving plastic wrap/bag placement sequentially following placental transfusion. Study Design Retrospective analysis of data from a multisite quality improvement initiative to refine stabilization procedures pertaining to placental transfusion and thermoregulation using a plastic wrap/bag. Delivery room practices and outcome data in 590 total cases receiving placental transfusion were controlled for propensity score matching and hospital of birth. Results The simultaneous and sequential groups were similar in demographic and most outcome metrics. The simultaneous group had longer duration of delayed cord clamping compared with the sequential group (42.3 ± 14.8 vs. 34.1 ± 10.3 seconds, p < 0.001), and fewer number of times cord milking was performed (0.41 ± 1.26 vs. 0.86 ± 1.92 seconds, p < 0.001). The time to initiate respiratory support was also significantly shorter in the simultaneous group (97.2 ± 100.6 vs. 125.2 ± 177.6 seconds, p = 0.02). The combined outcome of death or necrotizing enterocolitis in the simultaneous group was more frequent than in the sequential group (15.3 vs. 9.3%, p = 0.038); all other outcomes measured were similar. Conclusion Timing of plastic wrap/bag placement during placental transfusion did affect duration of delayed cord clamping, number of times cord milking was performed, and time to initiate respiratory support in the delivery room but did not alter birth hospital outcomes or respiratory care practices other than the combined outcome of death or necrotizing enterocolitis. Key Points

Missingness Adapted Group Informed Clustered (MAGIC)-LASSO: A novel paradigm for prediction in data with widespread non-random missingness

The availability of large-scale biobanks linking rich phenotypes and biological measures are a powerful opportunity for scientific discovery. However, real-world collections frequently have extensive non-random missing data. Machine learning methods are able to predict missing data but performance is significantly impaired by block-wise missingness inherent to many biobanks. To address this, we developed Missingness Adapted Group-wise Informed Clustered LASSO (MAGIC-LASSO) which performs hierarchical clustering of variables based on missingness followed by sequential Group LASSO within clusters. Variables are pre-filtered for missingness and balance between training and target sets with final models built using stepwise inclusion of features ranked by completeness. This research has been conducted using the UK Biobank (n>500k) to predict unmeasured Alcohol Use Disorders Identification Test (AUDIT.) The phenotypic correlation between measured and predicted total score was 0.67 while genetic correlations between independent subjects was >0.86, demonstrating the method has significant accuracy and utility.

SEQUENTIAL GROUP LENDING WITH AND WITHOUT GROUP LIABILITY; GRAMEEN I VERSUS GRAMEEN II

The paper shows that in absence of any physical collateral, sequential group lending with joint-liability fails to guarantee loan repayment by borrowers because of the coordination problem among the borrowers. The model finds that under certain conditions, profits can be higher under joint-liability group lending if one can ensure peer pressure is adequate to guarantee there is no strategic default, i.e., repayment when the borrower has earned enough to be able to repay. From the lender’s point of view, the individual lending contract may turn out to be a better option than joint-liability group lending under certain circumstances.

Sequential Foley Catheter and Misoprostol Versus Misoprostol Alone for Induction of Labor in Postdated Pregnancy: a Randomized Controlled Trial

Introduction: Induction of labor is done with the aim of normal vaginal delivery. There are different methods; mechanical like intra-cervical Foley’s or pharmacological agents like misoprostol ordinoprostone. Objectives: To compare sequential use of Foley’s catheter and vaginal misoprostol in comparison with vaginal misoprostol only. Methods: Patients with period of gestation more than or equal to 41 weeks without any complications were assigned randomly according to computer generated randomization into sequential use ofintracervical Foley followed by vaginal misoprostol after 24 hours (sequential group) or vaginalmisoprostol only. Primary outcome was rate of normal vaginal delivery. Secondary outcomes were induction to delivery interval, maternal and fetal morbidity. Results: Rate of normal vaginal delivery in sequential group (n= 353) and misoprostol alone group(n= 356) was 71.6% and 53.3% (p < 0.001) but the time to delivery from induction is statistically more in sequential group (30.3 vs. 11.2 hours, p< 0.001). Maternal outcomes like postpartum hemorrhage, hyper-stimulation syndrome, chorioamnitis and neonatal outcomes like low Apgar score, meconium stained baby and stillbirth are similar in both the groups. Conclusions: The priming of cervix using intracervical Foley catheter before giving vaginalmisoprostol was beneficial in increasing the rate of normal vaginal delivery but it increased the induction to delivery interval.

Perioperative observations of different bypass modes of a right coronary system based on instantaneous blood flow during the operation

Background: With the ageing of China's population, the incidence and mortality of coronary atherosclerotic heart disease (CAD) is increasing year by year, which brings a heavy burden to the family and society [1]. We aimed to analyse the strategy of coronary artery bypass grafting (CABG) in the right coronary artery and to compare the haemodynamic characteristics of the sequential grafts with those of single grafts and to observe the patency rate of those grafts for one week after the operation.Methods: A total of 242 patients (178 men, mean age 62.6±8.8 years) underwent right coronary artery bypass grafting in our hospital from October 2016 to January 2019. The blood flow (Q, ml/min), pulsatility index (PI) and related parameters of the grafts were measured and recorded by TTFM during the CABG. The patency of the grafts was evaluated by coronary computed tomography (CT) for one week after the operation. Results: The most common material used for the graft in the right coronary system of CABG is the greater saphenous vein (92.3%), followed by the radial artery (5.5%) and the internal mammary artery (1.9%). The highest frequency target of the right coronary artery is the posterior descending artery (PDA) (47.6%), followed by the right main coronary artery (RCA) (29.1%) and the posterior branch of the left ventricle (PL) (23.3%). The proportion of single grafts was the highest for the right coronary artery in CABG (178 cases, 67.9%), followed by a graft of the PDA-PL (42 cases, 16.0%) and other sequential grafts among the different coronary artery systems (including the system of the left anterior descending artery (LAD) and the left circumflex (LCX)). Whether there were sequential grafts of the PDA-PL or other sequential grafts among the different systems of the coronary artery, the instantaneous flow of a group of sequential grafts was higher than that of a single graft, and the difference had statistical significance (P < 0.01). However, there were no significant differences in the flow between the groups of sequential grafts (P = 0.410). Diastolic flow (DF) in the group of sequential grafts of the right coronary system was better than that in the non-sequential group (P < 0.001), and the difference had statistical significance. There was no significant difference between the DF of the groups of the other system of sequential grafts and that of the right coronary sequential grafts. Coronary artery CT suggested that there were 11 cases of poorly developing grafts or stenosis and occlusion a week after the operation, and those phenomenon mainly occurred in the group with a single graft. There was only one case that was occluded in the group of other systems of sequential grafts, and statistically significant differences existed between the two groups (P < 0.01).Conclusions: In our centre, the most common form of CABG in the right coronary artery system is a non-sequential vein bridge to the PDA. Whether there are sequential grafts of the PDA-PL or other sequential grafts among the different coronary artery systems, the instantaneous flow of a group of sequential grafts is higher than that of a single graft. DF in the group of sequential grafts of the right coronary system was better than that in the non-sequential group.

Osteonecrosis of the jaw (ONJ) in radium 223 (Ra223)-treated metastatic castration-resistant prostate cancer (mCRPC) patients (pts) with exposure to zoledronic acid and/or denosumab.

5575 Background: Bone health agents (BHA) including denosumab, a monoclonal antibody, and Zoledronic acid (ZA), a bisphosphonate, are recommended for men with CRPC and bone metastases to prevent skeletal-related complications. ONJ occurs in about 5% of patients (pts) on BHA. The incidence of ONJ in pts treated with Ra223 and BHA remains unknown, particularly in those who receive sequential treatment of BHAs. Here we describe the rate of ONJ in a real-world setting in mCRPC pts treated with Ra223 in 3 groups: 1) denosumab alone, 2) ZA alone, and 3) sequential ZA /denosumab or vice versa. Methods: A retrospective analysis of a cohort of mCRPC pts with bone metastases who received Ra223. Follow-up was until date of death or last data entry. Chart inclusion criteria included patients who received Ra223 between November 2010 to August 2018 with documentations of data points. Results: A total of 177 pts received Ra223 between 11/2010 and 8/2018. Median age 73 at 1st Ra223 (range 40-93); Median PSA 15.8- at 1st Ra223 (range 0.1-1952); Demographics-AA-10, C-130, Asian-9, unspecified-28; Median Alk Phos 95 at 1st Ra233 (range 25-1515). 93 % (164/177) received BHA. Of the 164 who received BHA, 45% (73/164) received denosumab only, 37% (61/164) received ZA only, and 18% (30/164) received sequential treatment. ONJ developed in 9.7% (16/164) of all patients on BHA. Denosumab alone caused ONJ in 7 of 73 pts (9.6%). ZA alone caused ONJ in 6 of 61 pts (9.8%). ONJ occurred in 3 of 30 pts (10%) in the sequential group. The median number of doses of BHA before development of ONJ was 10 with denosumab, 20 with ZA, and 19.5 (denosumab) and 22 (ZA) in the sequential group. Conclusions: In patients treated with Ra223 and a BHA, the rate of ONJ is 9.7%. The rate of ONJ was similar in groups treated with denosumab alone, ZA alone, and sequential treatment of ZA and denosumab However, ONJ developed more quickly in patients on denosumab. We conclude that the risk of ONJ is increased in patients treated with Ra223 and BHA. ZA or sequential therapy appears to delay time to onset of ONJ compared to denosumab. Clinicians should be mindful of the toxic synergy between Ra223 and BHA. ZA may be the preferred BHA partner with Ra223.

Radiotherapy with sequential αnti-PD-1 mAb compared with concurrent αnti-PD-1 mAb for enhancing the abscopal effect by promoting the inflammatory tumor microenvironment.

e15122 Background: Radiotherapy (RT) is one of the main approaches for treatment of lung cancer. A large number of preclinical and several clinical studies revealed that RT can activate the host’s anti-tumor immune system and induce abscopal effect. However, the optimal timing and its underlying mechanism of the combination of RT and immune checkpoint inhibitor (CHI) are unclear. Methods: MC38 cells were used for subcutaneous tumor formation in the left lower limbs (irradiation field) and the right lower limbs (non-irradiation field) of six-eight weeks old male C57BL/6 mice. When the tumor volume reached 150mm3, the mice were randomly assigned to receive RT (8Gy × 3F) with concurrent anti-PD-1 monoclonal antibody (mAb) or RT with sequential (1 week after the first irradiation) anti-PD-1 mAb (group B). The changes of immune microenvironment in irradiated and non-irradiated tumors in the two groups were analyzed by flow cytometry. Results: Both RT with concurrent anti-PD-1 mAb and RT with sequential anti-PD-1 mAb could inhibit the growth of tumors in non-irradiation field. The number of CD4+T cells (CD45+CD44+CD4+T) and effector CD4+T cells (CD44+CD4+IFNγ + T) in non-irradiated tumors in the sequential group was significantly higher than that in the concurrent group, but which showed no significant difference between the two groups in irradiated tumors. Interestingly, CD8+T cells (CD45+CD44+CD8+T) and effector CD8+T cells (CD44+CD8+IFNγ + T) increased both in the irradiation and non-irradiation field in the sequential group compared with that in the concurrent group, while tumor associated macrophages (TAM, F4/80+CD11b+) and Treg cells (CD4+FoxP3+) in the sequential group decreased significantly. RT with sequential anti-PD-1 mAb reduced more exhausted CD8+T cells (PD-1+Eomes+of CD8+T) and induced more reinvigoration of exhausted T cell (Ki-67+PD-1+Emoes+CD8+T). The decrease of MDSCs (Gr1+CD11b+) in the non-irradiated tumors was observed in both groups, but there was no difference in the extent of this decrease between two groups. Conclusions: Compared with the concurrent combination, RT with sequential anti-PD-1 mAb is more effective in promoting the inflammatory tumor microenvironment in out-field tumors and inducing the abscopal effect, which provides a new perspective for further exploring the mechanism of optimal timing of combination. Funding: 81972853, 81572279, 2016J004, LC2019ZD009, 2018CR033.