Search

Early-onset colorectal cancer (EO-CRC), diagnosed before age 50, is rising in incidence worldwide. Although post-surgical colonoscopy surveillance strategies exist, appropriate intervals in EO-CRC remain elusive, as long-term surveillance outcomes remain scant. We sought to compare findings of surveillance colonoscopies of EO-CRC with patients with average onset colorectal cancer (AO-CRC) to help define surveillance outcomes in these groups. Single-institution retrospective chart review identified EO-CRC and AO-CRC patients with colonoscopy and no evidence of disease. Surveillance intervals and time to development of advanced neoplasia (CRC and advanced polyps [adenoma/sessile serrated]) were examined. For each group, 3 serial surveillance colonoscopies were evaluated. Statistical analyses were performed utilizing log-ranked Kaplan-Meier method and Cox proportional hazards. A total of 1259 patients with CRC were identified, with 612 and 647 patients in the EO-CRC and AO-CRC groups, respectively. Compared with patients with AO-CRC, patients with EO-CRC had a 29% decreased risk of developing advanced neoplasia from time of initial surgery to first surveillance colonoscopy (hazard ratio, 0.71; 95% confidence interval, 0.52–1.0). Average follow-up time from surgical resection to first surveillance colonoscopy was 12.6 months for both cohorts. Overall surveillance findings differed between cohorts (P =.003), and patients with EO-CRC were found to have less advanced neoplasia compared with their counterparts with AO-CRC (12.4% vs 16.0%, respectively). Subsequent colonoscopies found that, while patients with EO-CRC returned for follow-up surveillance colonoscopy earlier than patients with AO-CRC, the EO-CRC cohort did not have more advanced neoplasia nor non-advanced adenomas. Patients with EO-CRC do not have an increased risk of advanced neoplasia compared with patients with AO-CRC and therefore do not require more frequent colonoscopy surveillance than current guidelines recommend. [ABSTRACT FROM AUTHOR]

EMR and endoscopic submucosal dissection (ESD) are both accepted resection strategies for Barrett's esophagus–related neoplasia and esophageal adenocarcinoma (EAC). However, a lack of consensus exists regarding which technique offers superior outcomes. This study aims to systematically review the evidence comparing EMR versus ESD in treating Barrett's neoplasia and EAC. We searched 3 databases (Embase, MEDLINE, Cochrane Central) through October 2023. We included studies comparing the efficacy of EMR and ESD for Barrett's neoplasia and EAC. Primary outcomes include en bloc, R0, and curative resection; complete remission of dysplasia (CRD), and local recurrence. Secondary outcomes encompass adverse events. Our search identified 905 records. Eleven studies were included in the final analyses. Data showed significantly higher en bloc resection rates with ESD (odds ratio [OR], 31.53; 95% confidence interval [CI], 10.02-99.19; P <.01; 7 studies). R0 resection rates were significantly higher with ESD (OR, 5.92; 95% CI, 2.75-12.77; P <.01; 8 studies). Curative resection rates tended to be higher with ESD (OR, 3.49; 95% CI, 0.86-14.14; P =.080; 4 studies). There was no significant difference in CRD rates (OR, 0.92; 95% CI, 0.37-2.26; P =.86; 3 studies). Local recurrence rates tended to be lower with ESD (OR, 0.35; 95% CI, 0.11-1.04; P =.058; 10 studies). As for adverse events, there was no significant difference in bleeding, perforation, and postoperative stricture rates. This systematic review and meta-analysis demonstrates that ESD achieves higher en bloc, R0, and curative resection rates, with a tendency toward lower recurrence rates. These results suggest that ESD may be a more effective option for managing Barrett's neoplasia and EAC. (International Prospective Register of Systematic Reviews [PROSPERO] registration number: CRD42023426486.) [Display omitted] [ABSTRACT FROM AUTHOR]

The COVID-19 vaccine was initially offered to frontline health care workers (HCWs), due to the high risk of contracting COVID-19 through occupational exposure to patients. Low HCW vaccine uptake can impact overall community-level vaccine uptake. This study used the Diffusion of Innovation (DOI) Theory to understand factors related to COVID-19 vaccine uptake in HCWs. We surveyed Pennsylvanian HCWs (excluding Philadelphia) from August 2022 to February 2023. Survey questions inquired about demographics, COVID-19 vaccination status, reasons for receiving/declining the COVID-19 vaccine, and sources of information about the vaccine. Participants (n = 3,490) were 85% female, 89% White, and 93% (n = 3,255) reported receiving at least one dose of a COVID-19 vaccine. HCWs were categorized into adopter categories of the DOI Theory: innovators (56%), early adopters (9%), early majority (11%), late majority (7%), and laggards (17%). The major reason that prompted participants to get the vaccine was to protect them against COVID-19 infection (78%), while the major reason for declining the vaccine was due to concern about possible side effects from the vaccine (78%). We applied the DOI Theory to characterize adopters and identify factors related to COVID-19 vaccine uptake in HCWs. As updated COVID-19 vaccines are approved for the United States market, our findings may be used to improve vaccine education and communication among HCWs to support vaccine uptake. • The Diffusion of Innovation Theory was used to characterize COVID-19 vaccine uptake. • Most health care workers were categorized as innovators and early adopters. • Factors related to COVID-19 vaccine uptake vary by category of adoption. [ABSTRACT FROM AUTHOR]

The incidence, risk factors, and outcomes of post-ERCP cholecystitis are poorly described. We aimed to describe cases of post-ERCP cholecystitis from a prospective multicenter registry with protocolized 30-day follow-up. Patient- and procedure-related data from 7 centers were obtained. The primary outcome was post-ERCP cholecystitis, defined according to a Delphi-based criteria and causal attribution system. Risk factors and outcomes were described for all cases. Seventeen cases of post-ERCP cholecystitis were identified among 4428 patients with gallbladders undergoing ERCP between 2018 and 2023 (incidence, 0.38%; 95% confidence interval, 0.20-0.57). In ERCPs with covered metal stenting, 7 of 467 resulted in cholecystitis (incidence, 1.50%; 95% confidence interval, 0.40-2.60). Patients had symptoms at a median of 5 days (interquartile range, 5) after ERCP. Management strategies included cholecystectomy, percutaneous cholecystostomy, and endoscopic stent removal/exchange. Estimates of post-ERCP cholecystitis incidence can inform discussions around procedural risk. [ABSTRACT FROM AUTHOR]

Stent dysfunction is common after ERCP with self-expandable metal stent (SEMS) insertion for malignant distal biliary obstruction (MDBO). Chronic aspirin (acetylsalicylic acid; ASA) exposure has been previously shown to potentially decrease this risk. We aim to further ascertain the protective effect of ASA and to identify other predictors of stent dysfunction. This multicenter retrospective cohort study was conducted at 9 sites in Canada and 1 in the United States. Patients with MDBO who underwent ERCP with SEMS placement between January 2014 and December 2019 were included and divided into 2 cohorts: ASA exposed (ASA-E) and ASA unexposed (ASA-U). Propensity-score matching (PSM) was performed to limit selection bias. Matched variables were age, sex, tumor stage, and type of metal stent. The primary outcome was the hazard rate of stent dysfunction. A multivariable Cox proportional hazards model was used to identify independent predictors of stent dysfunction. Of 1396 patients assessed, after PSM 496 patients were analyzed (248 ASA-E and 248 ASA-U). ERCP with SEMS placement was associated with a high clinical success of 82.2% in ASA-E and 81.2% in ASA-U cohorts (P =.80). One hundred eighty-four patients had stent dysfunction with a mean stent patency time of 229.9 ± 306.2 days and 245.4 ± 241.4 days in ASA-E and ASA-U groups, respectively (P =.52). On multivariable analysis, ASA exposure did not protect against stent dysfunction (hazard ratio [HR], 1.25; 95% confidence interval [CI],.96-1.63). An etiology of pancreatic cancer (HR, 1.36; 95% CI, 1.15-1.61) predicted stent dysfunction, whereas cancer therapy was protective (HR,.73; 95% CI,.55-.96). Chronic ASA use was not associated with an increased risk for adverse events including bleeding, post-ERCP pancreatitis, and perforation. In this large, multicenter study using PSM, chronic exposure to ASA did not protect against stent dysfunction in MDBO. Instead, the analysis revealed that the etiology of pancreatic cancer was an independent predictor of stent dysfunction and cancer therapy was protective. [ABSTRACT FROM AUTHOR]

• Research regarding the effective implementation of infection control processes in the long-term care setting is lacking. • Project ECHO is an innovative strategy to disseminate evidence-based programming during times of crises. • This study aimed to explore the effectiveness of ECHO versus ECHO+ in reducing the number of nursing home residents with COVID-19, hospitalizations, deaths, and flu-like illnesses. • A multipronged approach to improving infection control and emergency preparedness in nursing homes is important. Nursing homes were ill-equipped for the pandemic; though facilities are required to have infection control staff, only 3% have taken a basic infection control course. Little is known about the implementation of effective practices outside of the acute care setting. We proposed an intervention utilizing Project ECHO, to connect Penn State University experts with nursing home staff and administrators to explore how infection control guidelines can be implemented effectively. A stratified cluster randomized design was used to assign nursing homes to either AHRQ-funded COVID-19 ECHO or AHRQ-funded COVID-19 ECHO+. 136 nursing homes participated. There were no significant differences in COVID-19 infection rate, hospitalization, deaths, or influenza, between ECHO or ECHO+. The ECHO model has significant strengths when compared to traditional training, as it allows for remote learning delivered by a multidisciplinary team of experts and utilizes case discussions that match the context of nursing homes. [ABSTRACT FROM AUTHOR]

Resection of colorectal polyps has been shown to decrease the incidence and mortality of colorectal cancer. Large nonpedunculated colorectal polyps are often referred to expert centers for endoscopic resection, which requires relevant information to be conveyed to the therapeutic endoscopist to allow for triage and planning of resection technique. The primary objective of this study was to establish minimum expected standards for the referral of large nonpedunculated colonic polyps for potential endoscopic resection. A Delphi method was used to establish consensus on minimum expected standards for the referral of large colorectal polyps among a panel of international endoscopy experts. The expert panel was recruited through purposive sampling, and 3 rounds of surveys were conducted to achieve consensus. Quantitative and qualitative data were analyzed for each round. A total of 24 international experts from diverse continents participated in the Delphi study, resulting in consensus on 19 statements related to the referral of large colorectal polyps. The identified factors, including patient demographic characteristics, relevant medications, lesion factors, photodocumentation, and the presence of a tattoo, were deemed important for conveying the necessary information to therapeutic endoscopists. The mean scores for the statements, which were scored on a scale of 1 to 10, ranged from 7.04 to 9.29, with high percentages of experts considering most statements as a very high priority. Subgroup analysis according to continent revealed some variations in consensus rates among experts from different regions. The identified consensus statements can aid in improving the triage and planning of resection techniques for large colorectal polyps, ultimately contributing to the reduction of colorectal cancer incidence and mortality. [ABSTRACT FROM AUTHOR]

Pathology of the long head of the biceps can contribute to substantial shoulder pain. After nonoperative treatment has failed, either open or arthroscopic tenotomy or tenodesis can be recommended depending on age, occupation, function, and cosmetic preference. While classic tenodesis techniques rely on tendon-to-bone fixation, multiple studies have shown superior healing results for fixation between similar types of tissue, such as tendon-to-tendon. In this technique, we present the "sandwich technique," performed entirely arthroscopically. A single 4-strand anchor with bioabsorbable screw is used to provide 2 types of fixation. Two strands are first used to lasso-loop the long head of the biceps to the bicipital groove, providing bone-to-tendon fixation. The other strands are then used to anchor rotator interval tissue to the tendon, providing a similar tissue or tendon-to-tendon patch augmentation. Video 1 This video shows an all-arthroscopic biceps tenodesis using a bioabsorbable anchor. This technique is called "sandwich" tenodesis because it combined a soft-tissue fixation between the biceps tendon and rotator interval tissue from one hand, and a bony fixation between the biceps tendon and bicipital groove from the other hand. [ABSTRACT FROM AUTHOR]

Industry led schemes to eradicate the endemic cattle disease bovine viral diarrhoea involving government legislation represent a new type of biosecurity governance. This paper explores the governance of schemes to eradicate bovine viral diarrhoea in the UK and Ireland, using the concept of the institutional void. The institutional void describes the devolution of responsibility from central government to devolved administrations and industry. In addition, our research took place within the context of uncertainty over Brexit and how this will affect biosecurity governance within the UK, and the UK's relationship with EU countries, particularly Ireland. The paper draws on interviews with key stakeholders involved in the design and administration of the schemes across the UK and Ireland. The paper identifies three institutional logics that motivated the development of the schemes and their design to ensure successful disease eradication. The key findings from the paper were that though the schemes had a novel industry led design, novel governance mechanisms for ensuring compliance other than national government enforcement do not yet exist. The most common response to threats to the schemes' logic was to call for a scaling up of responsibility – from industry to government and from government to the EU. This may allow for the harmonisation of schemes and enforcement of compliance but may also open up fresh legitimacy challenges as control of the scheme is also scaled up from industry to government and government to the EU. While past research has shown that international biosecurity regulation can become depoliticised by the actors involved and is treated as a risk calculation exercise, this was not the case with BVD eradication schemes where the meaning of 'BVD free' was a politicised concept. The schemes represented a new departure in biosecurity governance and so raise the need to rethink what compliance means in an industry-government hybrid scheme – is it compliance with epidemiological advice or compliance with the law and how can these two meanings be best harmonised? • Schemes eradicating BVD in UK and Ireland are novel forms of biosecurity governance. • Schemes are industry led and involve industry-government partnerships. • Despite novel partnerships government seen as having responsibility for compliance. • Disagreements about role of government and whether BVD is public or industry good. • Harmonising schemes between countries was about scaling up responsibility to the EU. [ABSTRACT FROM AUTHOR]

In this paper we advance the conceptualisation of the 'good farmer' through integration of Bourdieusian concepts with DeLanda's assemblage theory. Considering new farms as assemblages is useful to unlock the relative power of association amongst component parts, and to understand what drives the emergence of a farm. Utilising an empirical case study of new entrants to crofting in Scotland, we assess the interlinked processes of new symbolic capital formation and new croft establishment. Following Bourdieu, the 'good farmer' concept provides an approach to identify how established and shifting norms of crofting shape new holding establishment. Findings develop the materiality of social and cultural capital formation, with 'good crofting' ideals coded in relation to land capacity, practical experiences working the farm, multifunctional transitions and crofting legislation. New entrants actively 'territorialise' (define) their crofts by integrating new markets and management practices. The historicity of new farm assemblage is evident in the active mobilisation of historic images to inform expectations of productivity. The authors argue that integration of assemblage theory with Bourdieusian concepts elucidates the flexibility of farming forms and identities, the role of 'more-than-human' actants in farming identity construction, and the role of legislation in shaping understanding of what farming should entail. This is important for academics and policy makers alike concerned with the efforts to revitalise rural and agrarian economies. • Social and cultural capital act as the 'glue' holding assemblages together. • Identity develops iteratively through experimentation with commodities. • De-territorialising involved identifying neighbours as 'bad crofters'. • New crofters establish hybrid identities, based on diffuse sources. • New entrants assert a mobilising identity to 'revitalise' crofting. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic seemingly is peaking now in New York City and has triggered significant changes to the standard management of gastrointestinal diseases. Priorities such as minimizing viral transmission, preserving personal protective equipment, and freeing hospital beds have driven unconventional approaches to managing gastroenterology (GI) patients. Conversion of endoscopy units to COVID units and redeployment of GI fellows and faculty has profoundly changed the profile of most GI services. Meanwhile, consult and procedural volumes have been reduced drastically. In this review, we share our collective experiences regarding how we have changed our practice of medicine in response to the COVID surge. Although we review our management of specific consults and conditions, the overarching theme focuses primarily on noninvasive measures and maximizing medical therapies. Endoscopic procedures have been reserved for those timely interventions that are most likely to be therapeutic. The role of multidisciplinary discussion, although always important, now has become critical. The support of our faculty and trainees remains essential. Local leadership can encourage well-being by frequent team check-ins and by fostering trainee development through remote learning. Advancing a clear vision and a transparent process for how to organize and triage care in the recovery phase will allow for a smooth transition to our new normal. [ABSTRACT FROM AUTHOR]

Study Objective: In the Emergency Department (ED) setting, clinicians commonly treat severely elevated blood pressure (BP) despite the absence of evidence supporting this practice. We sought to determine if this rapid reduction of severely elevated BP in the ED has negative cerebrovascular effects.Methods: This was a prospective quasi-experimental study occurring in an academic emergency department. The study was inclusive of patients with a systolic BP (SBP) > 180 mm Hg for whom the treating clinicians ordered intensive BP lowering with intravenous or short-acting oral agents. We excluded patients with clinical evidence of hypertensive emergency. We assessed cerebrovascular effects with measurements of middle cerebral artery flow velocities and any clinical neurological deterioration.Results: There were 39 patients, predominantly African American (90%) and male (67%) and with a mean age of 50 years. The mean pre-treatment SBP was 210 ± 26 mm Hg. The mean change in SBP was -38 mm Hg (95% CI -49 to -27) mm Hg. The average change in cerebral mean flow velocity was -5 (95% CI -7 to -2) cm/s, representing a -9% (95% CI -14% to -4%) change. Two patients (5.1%, 95% CI 0.52-16.9%) had an adverse neurological event.Conclusion: While this small cohort did not find an overall substantial change in cerebral blood flow, it demonstrated adverse cerebrovascular effects from rapid BP reduction in the emergency setting. [ABSTRACT FROM AUTHOR]

Endoscopic ultrasound–guided choledochoduodenostomy with a lumen-apposing metal stent (EUS-CDS) is a promising modality for management of malignant distal biliary obstruction (MDBO) with potential for better stent patency. We compared its outcomes with endoscopic retrograde cholangiopancreatography with metal stenting (ERCP-M). In this multicenter randomized controlled trial, we recruited patients with MDBO secondary to borderline resectable, locally advanced, or unresectable peri-ampullary cancers across 10 Canadian institutions and 1 French institution. This was a superiority trial with a noninferiority assessment of technical success. Patients were randomized to EUS-CDS or ERCP-M. The primary end point was the rate of stent dysfunction at 1 year, considering competing risks of death, clinical failure, and surgical resection. Analyses were performed according to intention-to-treat principles. From February 2019 to February 2022, 144 patients were recruited; 73 were randomized to EUS-CDS and 71 were randomized to ERCP-M. The mean (SD) procedure time was 14.0 (11.4) minutes for EUS-CDS and 23.1 (15.6) minutes for ERCP-M (P <.01); 40% of the former was performed without fluoroscopy. Technical success was achieved in 90.4% (95% CI, 81.5% to 95.3%) of EUS-CDS and 83.1% (95% CI, 72.7% to 90.1%) of ERCP-M with a risk difference of 7.3% (95% CI, –4.0% to 18.8%) indicating noninferiority. Stent dysfunction occurred in 9.6% vs 9.9% of EUS-CDS and ERCP-M cases, respectively (P =.96). No differences in adverse events, pancreaticoduodenectomy and oncologic outcomes, or quality of life were noted. Although not superior in stent function, EUS-CDS is an efficient and safe alternative to ERCP-M in patients with MDBO. These findings provide evidence for greater adoption of EUS-CDS in clinical practice as a complementary and exchangeable first-line modality to ERCP in patients with MDBO. ClinicalTrials.gov , Number: NCT03870386. The study compared 2 different procedures for treating blockages in the bile duct from certain types of cancer. The newer modality—endoscopic ultrasound-guided choledochoduodenostomy—had no major differences from the other procedure—endoscopic retrograde cholangiopancreatography with metal stenting—meaning that the former is a viable and safe alternative for patients with this condition, providing more treatment options for physicians and patients. [ABSTRACT FROM AUTHOR]

The freshwater ferns (Salviniales) are well represented in the Maastrichtian deposits of Cerro de los Fragmentos in the headwaters of the Río Chico, Golfo San Jorge Basin. The fossil material of Salviniaceae includes complete megaspore apparatuses with attached microspore massulae and dispersed megaspores, float systems and microspore massulae of Azolla . The new species Azolla colhuehuapensis displays distinctive morphological characters including relative small megaspore apparatuses with easily detached floats and usually attached eglochidiate massulae. The Marsileaceae are represented by the megaspore Molaspora lobata , microspores of Crybelosporites and vegetative remains of Marsileaceaephyllum sp. The assemblage also includes zygospores of the green filamentous algae Zygnemataceae, spores of Marchantiophyta and Monilophyta (Schizaeales), megaspores of Isoetalean affinity and Palm-type angiosperm pollen grains. All these organic microfossils and the associated palynomorphs indicate the presence of a freshwater environment where abundant water ferns were developing and reproducing. [ABSTRACT FROM AUTHOR]

We use blended quadrature rules to reduce the phase error of isogeometric analysis discretizations. To explain the observed behavior and quantify the approximation errors, we use the generalized Pythagorean eigenvalue error theorem to account for quadrature errors on the resulting weak forms [28]. The proposed blended techniques improve the spectral accuracy of isogeometric analysis on uniform and non-uniform meshes for different polynomial orders and continuity of the basis functions. The convergence rate of the optimally blended schemes is increased by two orders with respect to the case when standard quadratures are applied. Our technique can be applied to arbitrary high-order isogeometric elements. [ABSTRACT FROM AUTHOR]

With the increasing rates of same-day discharge following minimally invasive surgery for endometrial cancer, the need for and value of routine postoperative testing is unclear. This study aimed to determine whether routine postoperative laboratory testing following minimally invasive hysterectomy for endometrial cancer leads to clinically significant changes in postoperative care. This was a single-institution retrospective cohort study of patients undergoing minimally invasive hysterectomy for endometrial cancer by a gynecologic oncologist between June 2014 and June 2017. Patient demographics, preoperative comorbidities, operative and postoperative data, and pathologic findings were manually extracted from the patients' medical records. The financial burden of laboratory testing was computed using hospital-level cost data. Of the 649 women included in the analysis, most (91.4%) were White, with a mean age of 61 years, and mean body mass index of 38.0 kg/m2. The most common comorbidities were diabetes mellitus (31.9%, n=207), chronic pulmonary disease (7.9%, n=51), and congestive heart failure (3.2%, n=21). Median operative time was 151 minutes (range, 61–278), and median estimated blood loss was 100 mL (range, 10–1500). Most patients (68.6%, n=445) underwent lymphadenectomy. All patients had postoperative laboratory tests ordered: 100% complete blood count, 99.7% chemistry, 62.9% magnesium, 46.8% phosphate, 37.4% calcium, and 1.2% liver function tests. Twenty-six patients (4.0%) had a change in management owing to postoperative laboratory test results. Of these 26 women, 88% experienced a change in clinical status that would have otherwise prompted testing. Only 3 (0.5% of entire cohort) were asymptomatic: 1 received a blood transfusion for asymptomatic anemia, and the other 2, who did not carry a diagnosis of diabetes mellitus, had interventions for hyperglycemia. On univariable analysis, peripheral and cerebrovascular disease, diabetes mellitus with end-organ damage, and a Charlson Comorbidity Index of ≥3 were associated with increased odds of change in management; these were not significant on multivariable analysis. Routine postoperative laboratory evaluation in this cohort increased hospital costs by $292,000. Routine postoperative laboratory tests are unlikely to lead to significant changes in management for women undergoing minimally invasive hysterectomy for endometrial cancer, and may increase cost without providing a discernible clinical benefit. In the setting of strict postoperative guidelines, laboratory tests should be ordered when clinically indicated rather than as part of routine postoperative management for women undergoing minimally invasive hysterectomy for endometrial cancer. [ABSTRACT FROM AUTHOR]

In this work, we present a novel isogeometric analysis discretization for the Navier-Stokes- Cahn-Hilliard equation, which uses divergence-conforming spaces. Basis functions generated with this method can have higher-order continuity, and allow to directly discretize the higher- order operators present in the equation. The discretization is implemented in PetIGA-MF, a high-performance framework for discrete differential forms. We present solutions in a two- dimensional annulus, and model spinodal decomposition under shear flow. [ABSTRACT FROM AUTHOR]

This paper describes a telescopic solver for two dimensional h adaptive grids with point singularities. The input for the telescopic solver is an h refined two dimensional computational mesh with rectangular finite elements. The candidates for point singularities are first localized over the mesh by using a greedy algorithm. Having the candidates for point singularities, we execute either a direct solver, that performs multiple refinements towards selected point singularities and executes a parallel direct solver algorithm which has logarithmic cost with respect to refinement level. The direct solvers executed over each candidate for point singularity return local Schur complement matrices that can be merged together and submitted to iterative solver. In this paper we utilize a parallel multi-thread GALOIS solver as a direct solver. We use Incomplete LU Preconditioned Conjugated Gradients (ILUPCG) as an iterative solver. We also show that elimination of point singularities from the refined mesh reduces significantly the number of iterations to be performed by the ILUPCG iterative solver. [ABSTRACT FROM AUTHOR]

In this paper we present an application of Alternating Direction Implicit (ADI) algorithm for solution of non-stationary PDE-s using isogeometric finite element method. We show that ADI algorithm has a linear computational cost at every time step. We illustrate this approach by solving two example non-stationary three-dimensional problems using explicit Euler and Newmark time-stepping scheme: heat equation and linear elasticity equations for a cube. The stability of the simulation is controlled by monitoring the energy of the solution. [ABSTRACT FROM AUTHOR]

Resumo Objetivos O paciente queimado representa um desafio para o anestesiologista, pois se submete a várias intervenções cirúrgicas durante sua hospitalização e necessita de anestesia geral e relaxamento muscular na maior parte delas. Apresenta sistema respiratório comprometido e uma resposta aos relaxantes musculares que difere do paciente sadio; portanto, um monitoramento correto e reversão tornam‐se imprescindíveis. Avaliamos a eficácia e segurança do sugamadex nessa população. Material e métodos Estudo descritivo com caráter prospectivo que inclui quatro pacientes, todos eles considerados grandes queimados, submetidos a escarectomia com anestesia geral e relaxamento neuromuscular. Como variável principal tomou‐se o tempo de recuperação de TOF superior a 0,9 após a administração de sugamadex antes de extubação. Resultados O tempo médio de recuperação de uma razão TOF superior a 0,9 após a administração de sugamadex foi de 4,95 minutos (IC95% 3,25‐6,64; p = 0,53). Conclusões A reversão do relaxamento neuromuscular com sugamadex parece ser eficaz e segura no paciente queimado. Seriam necessários mais estudos analíticos, comparativos e de maior população para confirmar esses dados. Objectives The burn patient is a challenge for the anesthesiologist, undergoing several surgeries during admission, and requiring general anesthesia and muscle relaxation most of the times. They have respiratory system impairment and a response to muscle relaxants that differs from the healthy patient, thus proper monitoring and reversal is crucial. We analyzed sugammadex effectiveness and safety in this population. Material and methods Prospectively descriptive study including four patients, all of them considered major burn patients, who underwent escharotomy with general anesthesia and neuromuscular relaxation. The main variable was the time for recovery of a TOF higher than 0.9 after the administration of sugammadex before extubation. Results Mean time of recovery from a TOF ratio higher than 0.9 following the administration of Sugammadex was of 4.95 minutes 95% CI (3.25‐6.64, p = .53); Conclusions The reversion of neuromuscular relaxation with sugammadex appears to be effective and safe in the burn patient. More analytical, comparative studies, of larger populations would be necessary to confirm this data. [ABSTRACT FROM AUTHOR]

The neuropeptide nociceptin/orphanin FQ (N/OFQ) is the endogenous ligand of the G-protein-coupled receptor NOP. Cells from the immune system express the precursor preproN/OFQ and the NOP receptor, as well as secrete N/OFQ. The activation of the N/OFQ-NOP pathway can regulate inflammatory and immune responses. Several immune activities, including leukocyte migration, cytokine and chemokine production, and lymphocytes proliferation are influenced by NOP activation. It was demonstrated that cytokines and other stimuli such as Toll-like receptor agonist (e.g., lipopolysaccharide) induce N/OFQ production by cells from innate and adaptive immune response. In this context, N/OFQ could modulate the outcome of inflammatory diseases, such as sepsis and immune-mediated pathologies by mechanisms not clearly elucidated. In fact, clinical studies revealed increased levels of N/OFQ under sepsis, arthritis, and Parkinson's disease. Preclinical and clinical studies pointed to the blockade of NOP receptor signaling as successful strategy for the treatment of inflammatory diseases. This review is focused on experimental and clinical data that suggest the participation of N/OFQ-NOP receptor activation in the modulation of the immune response, highlighting the immunomodulatory potential of NOP antagonists in the inflammatory and immunological disturbances. [ABSTRACT FROM AUTHOR]

Introduction: Delay in current nucleic acid amplification testing for Neisseria gonorrhoeae and Chlamydia trachomatis has led to recommendations for presumptive treatment in patients with concern for infection and unreliable follow-up. In the urban setting, it is assumed that many patients have unreliable follow-up, therefore presumptive therapy is thought to be used frequently. We sought to measure the frequency of disease and accuracy of presumptive treatment for these infections.Methods: This was an observational cohort study performed at an urban academic Level 1 trauma center ED with an annual census of 95,000 visits per year. Testing was performed using the APTIMA Unisex swab assay (Gen-Probe Incorporated, San Diego, CA). Presumptive therapy was defined as receiving treatment for both infections during the initial encounter without confirmation of diagnosis.Results: A total of 1162 patients enrolled. Infection was present in 26% of men, 14% of all women and 11% of pregnant women. Despite high frequency of presumptive treatment, >4% of infected patients in each category went untreated.Conclusion: Inaccuracy of presumptive treatment was common for these sexually transmitted infections. There is an opportunity to improve diagnostic accuracy for treatment. [ABSTRACT FROM AUTHOR]

Summary: Background & aims: Cardiovascular disease, the most common cause for morbidity and mortality in end-stage renal disease (ESRD), has prompted the exploration of multiple approaches to improve outcomes. Cardiovascular risk factors such as oxidative stress (OxSt) and cardiac remodelling are common in ESRD and dialysis patients. Green tea (GT) is well recognized as reducing OxSt. This 6 months study evaluated in 20 ESRD patients under chronic dialysis, the effect of GT treatment (1 g/day as commercially available capsule) on cellular and plasma OxSt and proliferation related markers using a molecular biology approach. Methods: Mononuclear cell p22phox, Haeme Oxygenase (HO)-1 protein expression, and phosphorylated ERK1/2 status were evaluated in dialysis patients at baseline, after 3 and 6 months of GT treatment by Western blot analysis and plasma oxLDL by ELISA. Cardiac remodelling was assessed by echocardiographic left ventricular (LV) mass determination at baseline and at the end of the study. Results: GT treatment reduced p22phox and pERK1/2 from baseline while HO-1 increased. At baseline, LV mass correlated with both p22phox and oxLDL. GT treatment decreased LV mass from baseline, which correlated with oxLDL. 9 patients had LV hypertrophy at baseline, which, at 6 months, was normalized in 5 and reduced in 3, showing a parallel decrease of p22phox, pERK1/2, oxLDL and increase of HO-1. Conclusions: Treatment with GT decreased the expression of OxSt-related proteins tightly associated with cardiovascular disease and decreased LV mass. It appears highly likely that the addition of GT can provide a benefit in terms of cardiovascular protection in dialysis patients. [Copyright &y& Elsevier]

Abstract: We discretized the two-dimensional linear momentum, microrotation, energy and mass conservation equations from micropolar fluids theory, with the finite element method, creating divergence conforming spaces based on B-spline basis functions to obtain pointwise divergence free solutions [8]. Weak boundary conditions were imposed using Nitsche's method for tangential conditions, while normal conditions were imposed strongly. Once the exact mass conservation was provided by the divergence free formulation, we focused on evaluating the differences between micropolar fluids and conventional fluids, to show the advantages of using the micropolar fluid model to capture the features of complex fluids. A square and an arc heat driven cavities were solved as test cases. A variation of the parameters of the model, along with the variation of Rayleigh number were performed for a better understanding of the system. The divergence free formulation was used to guarantee an accurate solution of the flow. This formulation was implemented using the framework PetIGA as a basis, using its parallel stuctures to achieve high scalability. The results of the square heat driven cavity test case are in good agreement with those reported earlier. [Copyright &y& Elsevier]

Abstract: In this paper, we present a high-performance framework for solving partial differential equations using Isogeometric Analysis, called PetIGA, and show how it can be used to solve phase-field problems. We specifically chose the Cahn-Hilliard equation, and the phase-field crystal equation as test cases. These two models allow us to highlight some of the main advantages that we have access to while using PetIGA for scientific computing. [Copyright &y& Elsevier]

Abstract: In this paper we present a dynamic programming algorithm for finding optimal elimination trees for computational grids refined towards point or edge singularities. The elimination tree is utilized to guide the multi-frontal direct solver algorithm. Thus, the criterion for the optimization of the elimination tree is the computational cost associated with the multi-frontal solver algorithm executed over such tree. We illustrate the paper with several examples of optimal trees found for grids with point, isotropic edge and anisotropic edge mixed with point singularity. We show the comparison of the execution time of the multi-frontal solver algorithm with results of MUMPS solver with METIS library, implementing the nested dissection algorithm. [Copyright &y& Elsevier]

Abstract: We model high molecular weight homopolymers in semidilute concentration via Dissipative Particle Dynamics (DPD). We show that in model reduction methodologies for polymers it is not enough to preserve system properties (i.e., density ρ, pressure p, temperature T, radial distribution function g(r)) but preserving also the characteristic shape and length scale of the polymer chain model is necessary. In this work we apply a DPD-model-reduction methodology for linear polymers recently proposed; and demonstrate why the applicability of this methodology is limited upto certain maximum polymer length, and not suitable for solvent coarse graining. [Copyright &y& Elsevier]

Abstract: A variational multi scale approach to model blood flow through arteries is proposed. A finite element discretization to represent the coarse scales (macro size), is coupled to smoothed dissipative particle dynamics that captures the fine scale features (micro scale). Blood is assumed to be incompressible, and flow is described through the Navier Stokes equation. The proposed cou- pling is tested with two benchmark problems, in fully coupled systems. Further refinements of the model can be incorporated in order to explicitly include blood constituents and non-Newtonian behavior. The suggested algorithm can be used with any particle-based method able to solve the Navier-Stokes equation. [Copyright &y& Elsevier]

Abstract: Shape Memory Alloys (SMAs) are capable of changing their crystallographic structure due to changes of either stress or temperature. SMAs are used in a number of aerospace devices and are required in some devices in exotic environments. We are developing dynamic data driven application system (DDDAS) tools to monitor and change SMAs in real time for delivering payloads by aerospace vehicles. We must be able to turn on and off the sensors and heating units, change the stress on the SMA, monitor on-line data streams, change scales based on incoming data, and control what type of data is generated. The application must have the capability to be run and steered remotely as an unmanned feedback control loop. [Copyright &y& Elsevier]

Abstract: Phase field modeling has become a widely used framework in the computational material science community. Its ability to model different problems by defining appropriate phase field parameters and relating it to a free energy functional makes it highly versatile. Thermodynamically consistent partial differential equations can then be generated by assuming dissipative dynamics, and setting up the problem as one of minimizing this free energy. The equations are nonetheless challenging to solve, and having a highly efficient and parallel framework to solve them is necessary. In this work, a brief review on phase field models is given, followed by a short analysis of the Phase Field Crystal Model solved with Isogeometric Analysis us- ing PetIGA. We end with an introduction to a new modeling concept, where free energy functions are built with a periodic equilibrium structure in mind. [Copyright &y& Elsevier]

Abstract: In this work different nonlinear hyperelastic models for slightly compressible materials are implemented in an isogeometric finite element model. This is done within the recently developed computational framework called PetIGA, which uses isoge- ometric analysis and modern computational tools to solve systems of equations directly and iteratively. A flexible theoretical background is described to implement other hyperelastic models and possibly transient problems in future work. Results show quadratic convergence of the nonlinear solution consistent with the Newton-Raphson method that was used. Finally, PetIGA proves to be a powerful and versatile tool to solve these types of problems efficiently. [Copyright &y& Elsevier]

Abstract: This paper introduces a grammar-based model for developing a multi-thread multi-frontal parallel direct solver for one- dimensional isogeometric finite element method. The model includes the integration of B-splines for construction of the element local matrices and the multi-frontal solver algorithm. The integration and the solver algorithm are partitioned into basic indivisible tasks, namely the grammar productions, that can be executed squentially. The partial order of execution of the basic tasks is analyzed to provide the scheduling for the execution of the concurrent integration and multi-frontal solver algo- rithm. This graph grammar analysis allows for optimal concurrent execution of all tasks. The model has been implemented and tested on NVIDIA CUDA GPU, delivering logarithmic execution time for linear, quadratic, cubic and higher order B-splines. Thus, the CUDA implementation delivers the optimal performance predicted by our graph grammar analysis. We utilize the solver for multiple right hand sides related to the solution of non-stationary or inverse problems. [Copyright &y& Elsevier]

Abstract: Round-off error analysis has been historically studied by analyzing the condition number of the associated matrix. By controlling the size of the condition number, it is possible to guarantee a prescribed round-off error tolerance. However, the opposite is not true, since it is possible to have a system of linear equations with an arbitrarily large condition number that still delivers a small round-off error. In this paper, we perform a round-off error analysis in context of 1D and 2D hp-adaptive Finite Element simulations for the case of Poisson equation. We conclude that boundary conditions play a fundamental role on the round-off error analysis, specially for the so-called ‘radical meshes’. Moreover, we illustrate the importance of the right-hand side when analyzing the round-off error, which is independent of the condition number of the matrix. [Copyright &y& Elsevier]