Conditional Neural Heuristic for Multiobjective Vehicle Routing Problems.

Existing neural heuristics for multiobjective vehicle routing problems (MOVRPs) are primarily conditioned on instance context, which failed to appropriately exploit preference and problem size, thus holding back the performance. To thoroughly unleash the potential, we propose a novel conditional neural heuristic (CNH) that fully leverages the instance context, preference, and size with an encoder-decoder structured policy network. Particularly, in our CNH, we design a dual-attention-based encoder to relate preferences and instance contexts, so as to better capture their joint effect on approximating the exact Pareto front (PF). We also design a size-aware decoder based on the sinusoidal encoding to explicitly incorporate the problem size into the embedding, so that a single trained model could better solve instances of various scales. Besides, we customize the REINFORCE algorithm to train the neural heuristic by leveraging stochastic preferences (SPs), which further enhances the training performance. Extensive experimental results on random and benchmark instances reveal that our CNH could achieve favorable approximation to the whole PF with higher hypervolume (HV) and lower optimality gap (Gap) than those of the existing neural and conventional heuristics. More importantly, a single trained model of our CNH can outperform other neural heuristics that are exclusively trained on each size. In addition, the effectiveness of the key designs is also verified through ablation studies.

Psychological status of patients with functional anorectal pain and treatment efficacy of paroxetine in alleviating the symptoms: a retrospective study.

The aim of this study was to investigate the clinical characteristics, psychological status, sleep quality, and quality of life of patients with functional anorectal pain (FAP). The study also assessed the treatment efficacy of paroxetine in alleviating FAP symptoms. A retrospective comparative study of forty-three patients with FAP who were first treated with an anal plug compound glycolate suppository versus paroxetine combined with anal plug compound glycolate suppository between November 2021 and August 2022. Pain, quality of life, depression, anxiety and sleep quality were assessed before and after treatment by the Chinese version of the Short-Form McGill Pain Questionnaire-2 (SF-MPQ-2), Health-related quality of life scale (The 12-Item Short-Form Health Survey, SF-12), 17-item Hamilton Depression Rating Scale (HDRS), 14-item Hamilton Anxiety Scale (HAMA), and Pittsburgh Sleep Quality Index (PSQI). A total of 46.5% of patients with FAP were found to have anxiety symptoms (HAMA ≥ 7), 37.2% of patients with FAP were found to have depressive symptoms (HDRS ≥ 8). A total of 32.6% of patients with FAP had sleep disorders (PSQI > 10). Within 1 week after drug withdrawal, the short-term efficacy rate of oral paroxetine was 95.5%. After treatment, the symptom pain score (VAS) and sleep score were lower than those before treatment (P < 0.01). In the areas of vitality (VT), Social Functioning (SF), and Mental Health (MH), the difference between the pre-treatment and 8 weeks posttreatment scores of the study group and the control group was statistically significant (P < 0.05). FAP patients have obvious symptoms of anxiety and depression, and the incidence of sleep disturbance is prevalent. Paroxetine, a typical serotonin reuptake inhibitor (SSRI), was able to alleviate depression, anxiety, and pain symptoms in FAP, which might have clinical application prospects.

Natural course of perianal abscess in infants: a real-world study.

Natural course of perianal abscess (PA) in infancy remains obscure. This study aimed to investigate the natural course of infants with PA after conservative treatment. A retrospective cohort study was conducted in infants with PA who were treated conservatively (due to the parents' refusal of surgery), for more than 2 months between 2014 and 2020 at a single tertiary center. 153 patients (149 boys and 4 girls) were identified. The median follow-up was 5.3 years (range 3-8.2 years). Initially, 119 patients (77.8%) were completely cured by conservative treatment, and 34 (22.2%) failed. Among the 34 patients, 23 continued conservative treatment (20 cure, 3 fistula formation) and 11 underwent surgery. After conservative treatment, the rate of fistula formation, abscess recurrence, and new-onset abscess were 15.0%, 4.6%, and 6.5%, respectively. Overall, 139 patients (90.8%) were cured conservatively without surgery, and 11 (7.2%) underwent surgical management. In addition, 3 (2.0%) patients developed fistula-in-ano (under observation). PA in infants may be a time-limited and self-limited condition. Conservative management should be the first choice of treatment in most cases. Longer periods of conservative treatment may achieve better clinical outcomes in selected cases. There will be a percentage of patients (about 10%) that would require surgical treatment.