Influence of nanosecond repetitively pulsed discharges on the stability of a swirled propane/air burner representative of an aeronautical combustor.

This paper reports on an experimental study of the influence of a nanosecond repetitively pulsed spark discharge on the stability domain of a propane/air flame. This flame is produced in a lean premixed swirled combustor representative of an aeronautical combustion chamber. The lean extinction limits of the flame produced without and with plasma are determined and compared. It appears that only a low mean discharge power is necessary to increase the flame stability domain. Lastly, the effects of several parameters (pulse repetition frequency, global flowrate, electrode location) are studied.

Low back pain patients with Modic type 1 changes exhibit distinct bacterial and non-bacterial subtypes.

Objectives: Modic type 1 changes (MC1) are vertebral endplate bone marrow (BM) lesions observed on magnetic resonance images in sub-populations of chronic low back pain (CLBP) patients. The etiopathogenesis remains unknown and treatments that modify the underlying pathomechanisms do not exist. We hypothesized that two biological MC1 subtypes exist: a bacterial and a non-bacterial. This would have important implications for developing treatments targeting the underlying pathomechanisms. Methods: Intervertebral disc (IVD) samples adjacent to MC1 (n â€‹= â€‹34) and control (n â€‹= â€‹11) vertebrae were collected from patients undergoing spinal fusion. Cutibacterium acnes (C.acnes) genome copy numbers (GCNs) were quantified in IVD tissues with 16S qPCR, transcriptomic signatures and cytokine profiles were determined in MC1 and control BM by RNA sequencing and immunoassay. Finally, we assessed if C.acnes GCNs are associated with blood plasma cytokines. Results: IVD tissues from control levels had <870 â€‹C.acnes GCNs/gram IVD. MC1-adjacent IVDs had either "low" (<870) or "high" (>870) C.acnes GCNs. MC1 patients with "high" C.acnes GCNs had upregulated innate immune cell signatures (neutrophil, macrophage/monocyte) and pro-inflammatory cytokines related to neutrophil and macrophage/monocyte function in the BM, consistent with a host defense against bacterium. MC1 patients with "low" C.acnes GCNs had increased adaptive immune cell signatures (T-and B-cell) in the BM and elevated IL-13 blood plasma levels. Conclusion: Our study provides the first evidence for the existence of bacterial (C.acnes "high") and non-bacterial (C.acnes "low") subtypes in MC1 patients with CLBP. This supports the need for different treatment strategies.

Articular degeneration after subchondral cementation for giant cell tumors at the knee.

PURPOSE: To quantify joint degeneration and the clinical outcome after curettage and cementation in subchondral giant cell tumors of the bone (GCTB) at the knee. METHODS: We conducted a retrospective analysis of 14 consecutive patients (seven female, seven male) with a mean age of 34 years (range 19-51) who underwent curettage and subchondral cementation for a biopsy-confirmed GCTB at the distal femur or the proximal tibia between August 2001 and August 2017, with a mean follow-up period of 54.6 months (range 16.1-156 months). The Whole-Organ Magnetic Resonance Imaging Score (WORMS), Kellgren-Lawrence (KL) classification, and Musculo-Skeletal Tumor Society (MSTS) score were assessed. RESULTS: Radiological degeneration progressed from preoperative to the latest follow-up, with a median WORMS from 2.0 to 4.0 (p = 0.006); meanwhile, the median KL score remained at 0 (p = 0.102). Progressive degeneration (WORMS) tended to be associated with the proximity of the tumor to the articular cartilage (mean 1.57 mm; range 0-12 mm) (p = 0.085). The most common degenerative findings were cartilage lesions (n = 11), synovitis (n = 5), and osteophytes (n = 4). Mean MSTS score increased from 23.1 (preoperatively) to 28.3 at the latest follow-up (p < 0.01). Seven patients (50%) were treated for a local recurrence, with six revision surgeries performed. Removal of the cement spacer and filling of the cavity with a cancellous autograft was performed in seven patients. Conversion to a total knee arthroplasty was performed in one patient for local tumor control. CONCLUSIONS: Cementation following the curettage of GCTB around the knee is associated with slight degeneration at medium-term follow-up and leads to a significant reduction in pain. Removal of the cement and reconstruction with an autograft may be beneficial in the long term.

Giomer composite compared to glass ionomer in occlusoproximal ART restorations of primary molars: 24-month RCT.

BACKGROUND: Occlusoproximal restorations of primary molars usually fail, so it is necessary to investigate new materials that may overcome this challenge. Thus, this trial aimed to evaluate the longevity of occlusoproximal ART restorations in primary molars using a glass ionomer cement - GIC (Equia Forte® - GC Corp) and a Giomer resin composite - GCR (Beautifil Bulk Restorative® - Shofu Inc) after 24 months. METHODS: One hundred and eighty-two (182) children aged from 4 to 8 years were selected and randomly assigned to GIC or GCR. A paediatric dentist treated them in the school setting in Cerquilho, Brazil, and the restorations were assessed after 3, 6, 12, 18 and 24 months. The primary outcome was the restoration survival, evaluated using the Kaplan-Meier and superiority Cox regression analyses. Intention to treat (ITT) was performed as a sensitivity analysis using superiority test P value and confidence interval (CI = 95%). Independent variables included gender, age, molar, jaw, cavity volume and caries experience. RESULTS: The restoration survival after 24 months was GIC = 58.1% and GCR = 49.1% (HR = 1.24; CI = 0.97-1.59). ITT analysis showed a success of GIC = 61.1% and GCR = 52.2% (RR = 1.17; CI = 0.91-1.52). The superiority hypothesis was not proved in both analyses (P > 0.05). CONCLUSION: GCR does not have superior longevity than GIC in occlusoproximal ART restorations of primary molars.

Middle molecules in peritoneal equilibration test as a marker of peritoneal stress in children on continuous peritoneal dialysis.

At 1 month, 3 months, 6 months, and more than 6 months after healed peritonitis, we evaluated repeated peritoneal equilibration tests (PETs) for small molecules such as urea, and middle molecules such as cystatin C, beta 2-microglobulin, and alpha 1-microglobulin. We analyzed a total of 104 PETs in 21 children aged 1.7-18.6 years (median: 9.9 years). Equilibration quotients (D/P)--that is, substrate concentration in dialysis fluid (D) divided by substrate concentration in plasma (P)--were calculated after a dwell time of 4 hours. The D/P for urea did not change after healed peritonitis. In a cross-sectional study, the D/P for middle molecules showed an increase in peritoneal permeability between 3 months and 6 months after a healed peritonitis. In a consecutive follow-up of 4 patients for more than 6 months, beta 2-microglobulin and, more impressively, alpha 1-microglobulin showed a statistically significant increase in D/P (p < 0.05) 3 months after a healed peritonitis. All differences seen were completely reversible after more than 6 months, showing that peritoneal function is rather stable if peritonitis is healed. It is noteworthy that peritoneal dysfunction lasts for up to 6 months after a completely healed peritonitis. This period might be a vulnerable phase in continuation of peritoneal dialysis.

Variability of peritoneal equilibration test in children on continuous peritoneal dialysis by repeated testing with solutions of different osmolarity.

To evaluate (1) differences in the peritoneal equilibration test (PET) achieved using continuous peritoneal dialysis (CPD) solutions containing different amounts of glucose and (2) intraindividual reproducibility of PETs performed twice within an interval of 8 months on CPD, we investigated 39 PETs in 13 children aged 2.4-19.0 years (median 10.6 years) on stable CPD regimens. The fill volume was 1 L/m2 body surface area. We used a standard CPD solution (Fresenius) with a 2.3% glucose content (groups 2.3a and 2.3b) two times within an interval of 1-8 months. A third test was done between the two with a CPD solution of 1.5% glucose (group 1.5). Equilibration quotients, that is, substrate concentration in dialysis fluid divided by substrate concentration in plasma (D/P), did not show any statistically significant differences between groups 1.5 and 2.3a or between groups 2.3a and 2.3b. A significant difference was seen in the decline of glucose content of dialysate between groups 1.5 and 2.3 but not between groups 2.3a and 2.3b. Ultrafiltration was higher in groups 2.3a and 2.3b compared with group 1.5. Inter- and intraindividual variability between solute transfer was small during follow-up in stable CPD patients. Different glucose contents of 1.5 and 2.3 g/dL dialysis fluid had no measurable influence on PET results of stable CPD patients. For standard PETs, reducing the glucose content of dialysis fluid to isoosmolarity is not necessary.