Heat Transfer across the Free Surface of a Thermocapillary Liquid Bridge

The heat transfer across the free surface of a millimetric thermocapillary liquid bridge is investigated for two dimensional axisymmetric flows, computed by Newton–Raphson iteration. The coupled multiphase flow in the silicone-oil liquid bridge and in the ambient gas (air) is considered for Marangoni and Prandtl numbers of interest for typical space experiments. Based on the space-resolved heat flux of the two-phase flow for a wide range of parameters, we derive a model for the heat flux in form of Newton’s heat transfer law for a surrogate single phase flow, in which a space-dependent Biot function is considered. A parametric study for a 2 St silicone-oil liquid bridge is conducted for 150 configurations to derive a reliable fit of the Biot function for a wide range of Reynolds numbers and aspect ratios. An explicit form of the parametric fit is provided which takes into account the hot- and cold-wall boundary layers in the liquid

Healing of surgical site after total hip and knee replacements show similar telethermographic patterns

BACKGROUND: Isolated reports indicate the efficacy of infrared thermography for monitoring wound healing and septic complications, but no long-term analysis has ever been performed on this, and there are no data on the telethermographic patterns of surgical site healing after uncomplicated total hip prosthesis and after knee prosthesis. MATERIALS AND METHODS: In this prospective, observational, nonrandomized cohort study, two groups with forty consecutive patients each, who were operated on respectively for total hip and for total knee replacements, underwent telethermographic examination of the operated and contralateral joints prior to and at fixed intervals for up to 1\ua0year after uncomplicated surgery. A digital, portable telethermocamera and dedicated software were used for data acquisition and processing. RESULTS: No thermographic difference was observed preoperatively between the affected side and the contralateral side in both groups. After the intervention, a steep increase in the temperature of the operated joint was recorded after total hip replacement and after knee replacement, with a peak mean differential temperature measured three days postoperatively between the operated and unoperated joint of 3.1\ua0\ub1\ua00.8\ub0C after total hip replacement, and 3.4\ua0\ub1\ua00.7\ub0C after total knee replacement. Thereafter, the mean differential temperature declined slowly to 0.7\ua0\ub1\ua01.1\ub0C and to 0.5\ua0\ub1\ua01.3\ub0C at 60\ua0days, and to 0.0\ua0\ub1\ua01.0\ub0C and -0.1\ua0\ub1\ua01.1\ub0C 90\ua0days post-operatively, respectively. No further changes were observed for up to 1\ua0year after surgery. Results were similar when comparing the average telethermographic values of an elliptical area where the main axis corresponded to the surgical wound. CONCLUSIONS: The surgical sites after uncomplicated total hip or total knee replacement show similar telethermographic patterns for up to 1\ua0year from surgery, and can easily be monitored using a portable, digital, telethermocamera

Clinical and Virological Features and Course of Acute Hepatitis B (AHB) in Italy

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Short communication: Characterization of Staphylococcus aureus from bulk tank milk of dairy cattle in Lombardy (northern Italy).

ABSTRACT Staphylococcus aureus is one of the most important pathogens causing mastitis in cattle, and it is responsible for economic losses in dairy herds worldwide. The PCR amplification of the 16S-23S rRNA intergenic spacer (ribosomal spacer PCR, RS-PCR) allows a rapid classification of the strains in genotypes and genotypic clusters (CL), which are characterized by different epidemiological and clinical properties. Both RS-PCR and multi-locus sequence typing (MLST) were performed on strains isolated from bovine bulk tank milk (BTM) collected from dairy herds located in the Lombardy region (northern Italy), to outline the distribution of Staph. aureus genotypes in this geographical area. Out of 844 examined samples, 398 were positive for Staph. aureus, with a variable count (cfu/mL) Up to 8 colonies from each sample were genotyped. A total of 1,101 Staph. aureus strains were analyzed with RS-PCR, and only a selection of them (n = 86), in relation to their frequency and geographical origin, underwent MLST. This study revealed 8 major genotypic clusters (CLB, CLC, CLR, CLS, CLI, CLF, CLAO, and CLZ), of which Staph. aureus CLB (29.3%) was the most common. Samples of BTM positive for CLB had a Staph. aureus cfu/mL count significantly higher than the non-CLB positive ones. Our MLST analysis showed genotypes already known as bovine-associated in literature, such as clonal complexes CC8, CC97, and CC151. The same selection of 86 strains was also analyzed for the presence of the adlb gene, which was recently proposed as a possible marker of contagiousness. Most Staph. aureus belonging to CLB or CC8 carried the adlb gene (85%), whereas this gene was detected in only 9% of non-CLB strains (CLAA, CLBI, CLBJ, CLS). In conclusion, the present study confirms that Staph. aureus CLB, which is recognized as a contagious genotype, is a particularly relevant agent of intramammary infection in dairy cows in Lombardy, and indirectly supports the idea that adlb can be a possible marker of contagiousness of isolates

Successful staged hip replacement in septic hip osteoarthritis in osteopetrosis: a case report

<p>Abstract</p> <p>Background</p> <p>Osteopetrosis is a rare, inherited, bone disorder, characterized by osteosclerosis, obliteration of the medullary cavity and calcified cartilage. The autosomal dominant form is compatible with a normal life span, although fractures often result from minimal trauma, due to the pathologic nature of bone. Osteomyelitis is common in patients with osteopetrosis because of a reduced resistance to infection, attributed to the lack of marrow vascularity and impairment of white cell function. Only one case of osteomyelitis of the proximal third of the femur has been previously reported, treated with several repeated debridements and finally with femoral head resection. Here we present for the first time a case of a staged implant of a cementless total hip prosthesis for the treatment of a septic hip in femoral neck nonunion in osteopetrosis.</p> <p>Case presentation</p> <p>A 36-years-old woman, affected by autosomal dominant osteopetrosis was referred to our department because of a septic hip arthritis associated with femoral neck septic non-union, with draining fistulas. The infection occurred early after a plate osteosynthesis for a closed perthrocanteric fracture of the femur and persisted in spite of osteosynthesis removal, surgical debridement and external fixation. In our hospital the patient underwent accurate debridement, femoral head and greater trochanter resection, preparation of the diaphyseal intramedullary canal and implant of an antibiotic-loaded cement spacer. The spacer was exchanged after one month, due to infection recurrence and four months later, a cementless total hip arthroplasty was implanted, with no clinical and laboratory signs of infection recurrence at two years follow-up.</p> <p>Conclusions</p> <p>In case of hip septic arthritis and proximal femur septic non-union, femoral head resection may not be the only option available and staged total hip arthroplasty can be considered.</p

Single-level anterior cervical discectomy and interbody fusion using PEEK anatomical cervical cage and allograft bone

BACKGROUND: In an effort to avoid the morbidity associated with autogenous bone graft harvesting, cervical cages in combination with allograft bone are used to achieve fusion. The goal of the current study was to assess the reliability and efficacy of anterior cervical discectomy and interbody fusion (ACDF) using a PEEK anatomical cervical cage in the treatment of patients affected by single-level cervical degenerative disease. METHODS AND MATERIALS: Twenty-five patients affected by single-level cervical degenerative pathology between C4 and C7 were enrolled in this study. The clinical findings were assessed using the Neck Disability Index and the Visual Analog Scale. Surgical outcomes were rated according to Odom's criteria at last follow-up. Fusion was graded as poor, average, good or excellent by assessing the radiographs. Cervical spine alignment was evaluated by sagittal segmental alignment and sagittal alignment of the whole cervical spine preoperatively, 6 months postoperatively and at the last follow-up. RESULTS: Twenty-five patients underwent ACDF using a PEEK anatomical cervical cage. All patients had a minimum 2 years of follow-up. The operative levels were C4-C5 in 5 patients, C5-C6 in 12 patients and C6-C7 in 8 patients. Preoperatively, average NDI was 34, 13 at 6 months, and 10 at latest follow-up. The mean preoperative VAS was 7; the mean postoperative VAS at latest follow-up was 3. Good or excellent fusion was achieved in all patients within 10 months (mean 5 months). Preoperatively, average sagittal segmental alignment (SSA) was 0.2\ub0 and average sagittal alignment of the cervical spine (SACS) 15.8\ub0. Six months after surgery, average SSA was 1.8\ub0 and average SACS 20.9\ub0, and at last follow-up, average SSA was 1.6\ub0 and average SACS 18.5\ub0. CONCLUSION: Anterior cervical discectomy and interbody fusion using PEEK anatomical cervical cages can be considered a safe and effective technique to cure cervical disc herniation with intractable pain or neural deficit in cases where conservative treatment failed

Perceptions of the appropriate response to norm violation in 57 societies

Norm enforcement may be important for resolving conflicts and promoting cooperation. However, little is known about how preferred responses to norm violations vary across cultures and across domains. In a preregistered study of 57 countries (using convenience samples of 22,863 students and non-students), we measured perceptions of the appropriateness of various responses to a violation of a cooperative norm and to atypical social behaviors. Our findings highlight both cultural universals and cultural variation. We find a universal negative relation between appropriateness ratings of norm violations and appropriateness ratings of responses in the form of confrontation, social ostracism and gossip. Moreover, we find the country variation in the appropriateness of sanctions to be consistent across different norm violations but not across different sanctions. Specifically, in those countries where use of physical confrontation and social ostracism is rated as less appropriate, gossip is rated as more appropriate.info:eu-repo/semantics/publishedVersio

EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial

More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369