Estimation and analysis of the Hurst exponent for Australian stocks using wavelet analysis

This article presents an estimation and analysis of the Hurst exponent for Australian stocks using the wavelet technique. Consistent with Mulligan's (2004) study of US technology stocks, we find that the Hurst exponent varies over the cross-section of stocks. We also analyse Mulligan's (2004) and our data and find that beta can explain some of the cross-sectional variation in the Hurst exponents. However, we find that our results are not robust to filtering out the short range dependence in the data.

Resuscitation with Vitamin C, Hydrocortisone, and Thiamin in Children with Septic Shock: A Multicenter Randomized Pilot Study

OBJECTIVES: Adjunctive therapy with vitamin C, hydrocortisone, and thiamin has been evaluated in adults, but randomized controlled trial (RCT) data in children are lacking. We aimed to test the feasibility of vitamin C, hydrocortisone, and thiamin in PICU patients with septic shock; and to explore whether the intervention is associated with increased survival free of organ dysfunction. DESIGN: Open-label parallel, pilot RCT multicenter study. The primary endpoint was feasibility. Clinical endpoints included survival free of organ dysfunction censored at 28 days and nine secondary outcomes, shock reversal, and two proxy measures of intervention efficacy. SETTING: Six PICUs in Australia and New Zealand. PATIENTS: Children of age between 28 days and 18 years requiring vasoactive drugs for septic shock between August 2019 and March 2021. INTERVENTIONS: Patients were assigned 1:1 to receive 1 mg/kg hydrocortisone every 6 hours (q6h), 30 mg/kg ascorbic acid q6h, and 4 mg/kg thiamin every 12 hours (n = 27), or standard septic shock management (n = 33). MEASUREMENTS AND MAIN RESULTS: Sixty of 77 (78%) eligible patients consented with 91% of approached parents providing consent. The median time from randomization to intervention was 44 (interquartile range [IQR] 29-120) min. Seventy of seventy-seven (28%) patients had received IV steroids before randomization. Median survival alive and free of organ dysfunction was 20.0 (0.0-26.0) days in the intervention and 21.0 (0.0-25.0) days in the standard care group. Median PICU length of stay was 5.3 (2.5-11.3) days in the intervention group versus 6.9 (3.0-11.5) days in the control group. Shock reversal occurred at a median of 35.2 (14.6-101.2) hours in the intervention group versus 47.3 (22.4-106.8) hours in the standard care group (median difference -12 hr; 95% CI, -56.8 to 32.7 hr). CONCLUSIONS: In children requiring vasopressors for septic shock, a protocol comparing adjunctive treatment with high-dose vitamin C, hydrocortisone, and thiamin versus standard care was feasible. These findings assist in making modifications to the trial protocol to enable a better-designed larger RCT.</p

Fluid management and active fluid removal practices: a global survey of paediatric critical care physicians

Aims Fluid accumulation (FA) in critically ill children is associated with poor clinical outcomes. While conservative fluid management has been proposed, evidence to guide practice is scarce. We surveyed paediatric critical care (PCC) physicians worldwide regarding their perceptions of FA, active fluid removal (AFR) practices, safety parameters, and willingness to participate in a clinical trial on the topic. Methods Cross-sectional international electronic survey of PCC physicians, distributed through research networks worldwide. ResultsA total of 409 PCC physicians from 48 countries participated in the survey; 40% (164/409) cared for cardiac patients. The majority believed FA was a modifiable source of morbidity (88%, 359/407) and expressed support for a trial on conservative fluid management trial (94%, 383/407). Restriction of maintenance fluid was more commonly practiced (87%, 335/387) than resuscitation fluid (54%, 210/387), with variability observed among individuals and patient categories. AFR was widely practiced (93%, 361/387), yet significant differences existed in patient selection, timing, modality, and rate. The most common reported time for starting AFR was 48 h (49%, 172/384), with most respondents (92%, 355/385) comfortable doing so in the setting of catecholamine infusions. While most respondents would continue diuretics with mild electrolyte or acid–base disturbances, 52% (179/342) would withhold them in cases of mild hypotension. Conclusions Fluid accumulation remains a significant concern among paediatric intensivists. The observed practice variability underscores the challenges in establishing evidence-based guidelines. Our survey highlights an urgent need for randomized trials in this field and provides valuable insights to inform the design of such future studies

High rate of persistent symptoms up to 4 months after community and hospital-managed SARS-CoV-2 infection

Recovery after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains uncertain. A considerable proportion of patients experience persistent symptoms after SARS-CoV-2 infection which impacts health-related quality of life and physical function