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We address the problem of position control of micro-chips (chiplets) immersed in a fluid. An electric field, shaped by controlling the voltages of spiral-shaped electrodes, is used to reliably and accurately transport and position chiplets using dielectrophoretic forces. A lumped, capacitive-based (nonlinear) motion model is used to generate an open loop control policy. The spatial dependency of the capacitances is estimated using detailed electrostatic COMSOL simulations. The open loop policy is generated using a one step model predictive control approach. By exploiting the spatial symmetry and periodicity of the open loop control solution, a real-time control scheme is designed by applying simple algebraic operations to a base function defined on a finite domain. The chiplets position is tracked using image processing algorithms. We demonstrate the validity of our approach with an experiment where real-time control is used to move a chiplet for $1000~\mu \text{m}$ in a controlled manner. The results shown in this paper represent a critical step for the realization of a system that can digitally convert a design directly to the physical placement of micro-chips. [2018-0279]

BACKGROUND: As the cost of care for patients with specific diagnoses becomes fixed, hospitals must develop systems to reduce length of stay and optimize the utilization of hospital resources while maintaining a high quality of care. The goal of this study is to evaluate the implementation and efficacy of a system designed to reduce average length of stay on a vascular surgery service. STUDY DESIGN: To effectively reduce our average length of stay we restructured patient rounds, implemented multi-disciplinary rounds, introduced clinical pathways to post-operative care, and expanded outpatient management of post-operative patients. 1697 adult vascular surgery patients discharged while under the medical direction of a vascular surgeon between 7/1/2013 and 6/30/2016 were included in the study. RESULTS: Improving communication with critical staff and utilizing procedural space outside of the main operating rooms led to a 2.8-day reduction in length of stay (10.8 vs 8.0, P < 0.001). There was a trend toward a reduction in 30-day readmission rate (12% vs. 10%, respectively; P = 0.01) and no significant difference in case-mix index as a measure of illness severity (2.5 vs. 2.4, respectively; P = 0.15). Length of stay reductions were heterogeneous among the types of vascular disease studied, with greater improvements seen in patients undergoing lower extremity amputation, lower extremity angiogram, and endovascular aneurysm repair for non-ruptured abdominal aortic aneurysm. Less pronounced differences were observed in patients undergoing carotid artery endarterectomy/stenting and lower extremity bypasses. CONCLUSIONS: Restructuring team rounds and instituting a multidisciplinary approach to discharge planning produced significant reductions in length of stay without a deleterious effect on patient care that may impact hospital profitability.

We investigate the association between bond returns and 32 financial statement variables. Our findings show that 17 of the 32 financial statement measures we examined are significantly related to f...

Background National guidelines recommend screening and treatment for cancer-related bone disease and continued monitoring of bone-modifying agents. It is unclear whether a standardized screening tool is utilized to identify eligible patients and ensure appropriate supportive care is implemented. The purpose of this study was to evaluate current prescribing practices and optimize management of bone-modifying agents. Methods A retrospective chart review was performed to identify patients who received hormone deprivation therapy or had bone metastases through Hematology/Oncology or Urology clinics from 1 November 2016 to 31 October 2017. The primary endpoints of this study were the incidence of completed baseline dual-energy X-ray absorptiometry (DEXA) scan for patients on hormone deprivation therapy and percent of patients started on a bone-modifying agent for the prevention of skeletal-related events secondary to bone metastasis. Secondary endpoints included percent of patients with dental examinations prior to initiation, adequate calcium and vitamin D supplementation, incidence of osteonecrosis of the jaw or flu-like symptoms and education, and percent of bisphosphonate doses appropriately adjusted based on renal function. Results A total of 375 patients were assessed for baseline DEXA scans and bone-modifying therapy. Of the 226 patients on hormone deprivation therapy, 111 (49%) patients were appropriately screened with a DEXA scan prior to initiation of hormone deprivation therapy. Among the 149 patients with bone metastases, only 94 (63.1%) patients were started on a bone-modifying agent. Conclusions Opportunities have been identified to optimize management of patients with cancer-related bone disease. Implementation of standardized tools may increase the rate of appropriate screening and initiation of bone-modifying therapy when warranted.

Building on social exchange theory, this study examines the relationship between perceptions of organizational politics and employee performance and interpersonal skills. We hypothesized that perce...

We measure the welfare distortions from endogenous quality choice in imperfectly competitive markets. For US cable television markets between 1997–2006, prices are 33 percent to 74 percent higher and qualities 23 percent to 55 percent higher than socially optimal. Such quality overprovision contradicts classic results in the literature and our analysis shows that it results from the presence of competition from high-end satellite TV providers: without the competitive pressure from satellite companies, cable TV monopolists would instead engage in quality degradation. For welfare, quality overprovision implies cable customers would prefer smaller, lower-quality cable bundles at a lower price, amounting to a twofold increase in consumer surplus for the average consumer. (JEL L13, L15, L82)

The proliferation of small unmanned aerial systems (sUAS) is making very high-resolution imagery attainable for vegetation classifications, potentially allowing land managers to monitor vegetation in response to management or wildlife activities and offering researchers opportunities to further examine relationships among wildlife species and their habitats. The broad adoption of sUAS for remote sensing among these groups may be hampered by complex coding, expensive equipment, and time-consuming protocols. We used a consumer sUAS, semiautomated flight planning software, and graphical user interface GIS software to classify grassland vegetation with the aim of providing a user-friendly framework for managers and ecological researchers. We compared the overall accuracy from classifications using this sUAS imagery (89.22%) to classifications using freely available National Agriculture Imagery Program imagery (76.25%) to inform decisions about cost and accuracy. We also compared overall accuracy between manual classification (89.22%) and random forest classification (69.26%) to aid with similar decisions. Finally, we examined the impact of resolution and the addition of a canopy height model on classification accuracy, obtaining mixed results. Our findings can help new users make informed choices about imagery sources and methodologies, and our protocols can serve as a template for those groups wanting to perform similar vegetation classifications on grassland sites without the need for survey-grade equipment or coding. These should help more land managers and researchers obtain appropriate grassland vegetation classifications for their projects within their budgetary and logistical constraints.

The pleiotropic chemokine CXCL12 is involved in diverse physiological and pathophysiological processes, including embryogenesis, hematopoiesis, leukocyte migration, and tumor metastasis. It is known to engage the classical receptor CXCR4 and the atypical receptor ACKR3. Differential receptor engagement can transduce distinct cellular signals and effects as well as alter the amount of free, extracellular chemokine. CXCR4 binds both monomeric and the more commonly found dimeric forms of CXCL12, whereas ACKR3 binds monomeric forms. Here, we found that CXCL12 also bound to the atypical receptor ACKR1 (previously known as Duffy antigen/receptor for chemokines or DARC). In vitro nuclear magnetic resonance spectroscopy and isothermal titration calorimetry revealed that dimeric CXCL12 bound to the extracellular N terminus of ACKR1 with low nanomolar affinity, whereas the binding affinity of monomeric CXCL12 was orders of magnitude lower. In transfected MDCK cells and primary human Duffy-positive erythrocytes, a dimeric, but not a monomeric, construct of CXCL12 efficiently bound to and internalized with ACKR1. This interaction between CXCL12 and ACKR1 provides another layer of regulation of the multiple biological functions of CXCL12. The findings also raise the possibility that ACKR1 can bind other dimeric chemokines, thus potentially further expanding the role of ACKR1 in chemokine retention and presentation. published

Objective To describe the outcomes of robotic ventral hernia repair (rVHR) with varying prosthetic reinforcement techniques. Summary background data As a recent addition to minimally invasive hernia repair, more data is needed to establish the long-term benefits of rVHR and to identify potential predictors of adverse outcomes. Methods Patients who underwent rVHR over a 7-year period were evaluated. Robotic intraperitoneal onlay mesh (rIPOM), transabdominal preperitoneal (rTAPP), Rives-Stoppa (rRS), and transversus abdominis release (rTAR) techniques were compared. The main outcomes were 90-day freedom from complication (FFC) and 5-year freedom from recurrence (FFR), depicted through Kaplan-Meier curves stratified by repair type and date. Results A total of 644 rVHRs were analyzed; 197 rIPOM, 156 rTAPP, 153 rRS, and 138 rTAR. There was a gradual transition from intraperitoneal to extraperitoneal mesh placement across the study period. While rTAPP had the highest 90-day FFC (89.5%) it also had the lowest 5-year FFR (93.3%). Conversely, while rTAR demonstrated the lowest FFC (71%), it had the highest FFR (100%). Coronary artery disease, lysis of adhesions, incisional hernia, and skin-to-skin time (10 min. increment) were significant predictors of 90-day complications. Incisional hernia was the sole predictor of 5-year recurrence. Conclusions This study provides an in-depth perspective of the largest series of rVHR. Based on this experience, rTAPP is no longer recommended due to its limited applicability and high recurrence rate. Both rIPOM and rRS offer encouraging short- and long-term outcomes, while rTAR is associated with the highest perioperative morbidity. Longer follow-up is needed to assess rTAR durability, despite a promising recurrence profile.

Current research in the recognition of American Sign Language (ASL) has focused on perception using video or wearable gloves. However, deaf ASL users have expressed concern about the invasion of privacy with video, as well as the interference with daily activity and restrictions on movement presented by wearable gloves. In contrast, RF sensors can mitigate these issues as it is a non-contact ambient sensor that is effective in the dark and can penetrate clothes, while only recording speed and distance. Thus, this paper investigates RF sensing as an alternative sensing modality for ASL recognition to facilitate interactive devices and smart environments for the deaf and hard-of-hearing. In particular, the recognition of up to 20 ASL signs, sequential classification of signing mixed with daily activity, and detection of a trigger sign to initiate human-computer interaction (HCI) via RF sensors is presented. Results yield %91.3 ASL word-level classification accuracy, %92.3 sequential recognition accuracy, 0.93 trigger recognition rate.

Over the years, there has been much research in both wearable and video-based American Sign Language (ASL) recognition systems. However, the restrictive and invasive nature of these sensing modalities remains a significant disadvantage in the context of Deaf-centric smart environments or devices that are responsive to ASL. This paper investigates the efficacy of RF sensors for word-level ASL recognition in support of human-computer interfaces designed for deaf or hard-of-hearing individuals. A principal challenge is the training of deep neural networks given the difficulty in acquiring native ASL signing data. In this paper, adversarial domain adaptation is exploited to bridge the physical/kinematic differences between the copysigning of hearing individuals (repetition of sign motion after viewing a video), and native signing of Deaf individuals who are fluent in sign language. Domain adaptation results are compared with those attained by directly synthesizing ASL signs using generative adversarial networks (GANs). Kinematic improvements to the GAN architecture, such as the insertion of micro-Doppler signature envelopes in a secondary branch of the GAN, are utilized to boost performance. Word-level classification accuracy of 91.3% is achieved for 20 ASL words.

Despite heightened interest in robotic transversus abdominis release (rTAR), concerns over its steep learning curve (LC) and associated challenges may limit its adoption. This study defines the operative time and morbidity-based LC of a single surgeon’s experience with rTAR. A retrospective analysis of patients undergoing rTAR over an 8-year period was conducted. Consecutive ventral and incisional hernia repairs were stratified into four sub-categories based on bilaterality and complexity, with complex hernias being defined as those > 10 cm. Cumulative sum analyses (CUSUM) were used to evaluate skin-to-skin time and morbidity LCs. This study included a total of 156 rTARs with a mean skin-to-skin time of 222.8 min. Mean skin-to-skin times (min) for sub-categories were as follows: unilateral non-complex (137.6), bilateral non-complex (206.8), unilateral complex (241.9), and bilateral complex (298.6). The CUSUM-LC was obtained by summing the differences between each procedure’s operative time and its sub-category mean, revealing a quadratic best-fit line maximum at case 49 and a transition point between early and late phases at case 75. Although skin-to-skin times between early and late phases did not differ significantly (235.3 vs 211.2, respectively; p = 0.12), a significant difference was found in console times. Overall postoperative complications also decreased significantly from early to late phases (41.3% vs 25.9%; p = 0.041). Postoperative complications were predicted by a history of wound infection (c = 0.61). This study reveals that the rTAR LC was overcome between 49 and 75 cases, after which, console time and postoperative complications decreased significantly.

A multi-fluid magnetohydrodynamic model has been developed to investigate artificial clouds in the lower ionosphere. The model is based on the five-moment approximation of the fluid equations with ...

PURPOSE: The primary objective of this study was to evaluate the impact of a pharmacist-driven oral antineoplastic (OAN) renewal clinic on medication adherence and cost savings. METHODS: This was a preimplementation and postimplementation retrospective cohort evaluation within a single US Department of Veterans Affairs health care system following implementation of a pharmacist-managed OAN refill clinic. The primary outcome was medication adherence defined as the median medication possession ratio (MPR) before and after implementation of the clinic. Secondary outcomes included the proportion of patients who were adherent from pre- to postimplementation and estimated cost-savings of this clinic. Patients were eligible for inclusion if they had received at least 2 prescriptions of the most commonly prescribed oral antineoplastic agents at the institution between September 1, 2013 and January 31, 2015. RESULTS: Of preimplementation patients, 96 of 99 (96.9%) were male and all patients (n = 35) in the postimplementation group were male. The mean age of the preimplementation group was 69.2 years while the postimplementation group was 68.4 years. Median MPR in the preimplementation group was 0.94, compared with 1.06 in the postimplementation group (P < .001). Thirty-six (36.7%) patients in the preimplementation group were considered nonadherent to their OAN regimen compared with zero patients in the postimplementation group. Estimated total cost savings was $36,335 in the postimplementation period. CONCLUSIONS: Implementation of a pharmacist-driven OAN renewal clinic was associated with a 12% increase in median MPR while saving an estimated $36,335 during the 5-month postimplementation period.

OBJECTIVE When the integrated vascular surgery training pathway was introduced, training was comprised of nearly equal amounts of core general surgery and vascular surgery experience. However, specific requirements for case numbers or types were not defined. Over time, the time spent on core general surgery requirements has been reduced, most recently in 2018, from 24 to 18 months. We sought to determine trends in general surgery case volume and type over the past 10 years for vascular surgery residents. METHODS We conducted a retrospective review of the Accreditation Council for Graduate Medical Education case log data for integrated vascular surgery graduates from 2012-2018. We evaluated trends in mean numbers of cases, categorized as general surgery open (GS-open), general surgery laparoscopic (GS-laparoscopic), vascular surgery open (VS-open), and vascular surgery endovascular (VS-endo). Cases were also categorized by anatomic region as head/neck, thoracic, or abdominal. RESULTS The mean number of total head/neck, thoracic, or abdominal cases logged by graduating integrated vascular surgery trainees was 263.5. This total, as well as the proportion of general surgery cases (35%-38%, p = 0.99) has remained constant over time. The type of general surgery cases has changed significantly, with an upward trend in the mean number of GS-open cases and downward trend in mean GS-laparoscopic cases (GS-open p = 0.006, GS-laparoscopic p = 0.048). Among head/neck and thoracic subgroups, no significant changes were observed, while in the abdominal subgroup, there has been a significant increase in GS-open over time (p = 0.005). Additionally, the number of open vascular abdominal aortic cases has remained stable, with an average of 36.82 per graduating trainee per year. CONCLUSIONS In the 10 years since the introduction of integrated vascular surgery programs, total case volume and proportion of general surgery cases have remained remarkably stable. The type of general surgery cases has shifted though, with a decrease in GS-laparoscopic cases, replaced primarily by open abdominal cases. These changes likely reflect integrated vascular residents actively seeking out these opportunities during their core rotations and a willingness by general surgery partners to provide these opportunities. At the program level, these data may help guide program directors’ choices about the specific core rotations they incorporate into their curriculum. At the national level, this information may contribute to future discussions regarding the optimal number of core general surgery rotation requirements.

Modern Intelligent Virtual Agents (IVAs) are gradually progressing from just voice control tools to interactive, rich, humanlike social systems. However, creating these social humanlike IVAs is usually a daunting task and may present challenges for novice programmers, given the high technical complexity of practical implementation. In this work, we present AvaFlow, a web-based educational flow-based programming tool designed to assist novice programmers with creating and deploying IVA prototypes. We also aim to expand the use of the tool beyond IVAs to teach additional CS concepts related to data-driven applications.

We aim to develop the capability to rapidly sort, place, and orient micro objects into custom positions and transfer them to a final substrate eventually at costs similar to laser printers assembling toner particles onto paper. We are using programmable directed electrostatic parallel control to move particles from random to ordered patterns. Such a process could enable significantly more heterogeneity, complexity and customizability in material and device integration. We summarize experimental results including assembly and transfer microchip and microbeads at the 1um to 250um size scale, combined with transfer (including roll-roll based) to a final substrate.

Objective The degree of carotid artery stenosis, calculated using catheter-based angiography and the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method, has been shown to predict the stroke risk in several, large, randomized controlled trials. In the present era, patients have been increasingly evaluated using computed tomography (CT) angiography (CTA) before carotid artery revascularization, especially as the use of transcarotid artery revascularization has increased. Interpretation of CTA findings regarding the degree of carotid stenosis has not been standardized, with both NASCET methods and the area stenosis used. We performed a single-institution, blinded, retrospective analysis of CTA studies using both the NASCET method and the CT-derived area stenosis to assess the concordance and discordance between the two methods when evaluating ≥70% and ≥80% stenosis. Methods The UMass Memorial Medical Center vascular laboratory database was queried for all carotid duplex ultrasound scans performed from 2008 to 2017. The included patients were limited to those with duplex-defined ≥70% stenosis (defined as a peak systolic velocity of ≥125 cm/s and an internal carotid artery/common carotid artery ratio of ≥4), and a correlative CTA study performed within 1 year of the duplex ultrasound examination. A blinded review of all correlative CTA studies using centerline measurements on a three-dimensional workstation (Aquarius iNtuition Viewer; Terarecon, Durham, NC) was performed to characterize the degree of carotid stenosis using the NASCET method and the area stenosis method. Patients were excluded if revascularization had been performed between the two imaging studies. Results Of the 37,204 carotid duplex ultrasound scans reviewed (performed from 2008 to 2017), 3480 arteries met the criteria for duplex ultrasound-defined ≥70% stenosis. A correlative CTA study within 1 year of the duplex ultrasound examination was identified in 460 arteries, of which 320 were adequate quality for blinded review. The median interval between the duplex ultrasound and CTA examinations was 9.5 days. Concordance between the area stenosis and NASCET methods was poor for both ≥70% (κ = 0.32) and ≥80% (κ = 0.25) stenosis. Of the 247 arteries considered to have ≥70% area stenosis, 127 (51.4%) were considered to have ≥70% stenosis using the NASCET method. Of the 169 arteries considered to have ≥80% area stenosis, 44 (26.0%) were considered to have ≥80% stenosis using the NASCET method. Conclusions The area stenosis CTA calculations of carotid artery stenosis dramatically overestimated the degree of carotid stenosis compared with that calculated using the NASCET method. Given that stroke risk estimates have been determined from trials that used the NASCET method, the area stenosis method likely overestimates the risk of stroke. Therefore, area stenosis calculations could lead to unnecessary carotid revascularization procedures. This model highlights the need for standardized usage of the NASCET method when using CTA as the imaging modality to determine the threshold for carotid revascularization.

BACKGROUND Fenestrated/branched endovascular aneurysm repair (F/BEVAR) is a minimally invasive alternative for patients at high risk of open repair of complex aortic aneurysms. Nearly all investigative study protocols evaluating F/BEVAR have required a predicted life expectancy of >2 years for study inclusion. However, accurate risk models for predicting 2-year survival in this patient population are lacking. We sought to identify the preoperative predictors of 2-year survival for patients undergoing F/BEVAR. METHODS The prospectively collected data for all consecutive F/BEVAR procedures, performed in an institutional review board-approved registry and/or a physician-sponsored investigational device exemption (IDE) trial (IDE no. G130210), were reviewed (November 2010 to February 2019). We assessed 44 preoperative patient characteristics, including comorbidities, preoperative functional status, aneurysm morphologies, and repair techniques. Preoperative functional status was defined as totally dependent (any impairment in activities of daily living or residing in a skilled nursing facility), partially dependent (any impairment in instrumental activities of daily living), or independent (no impairment in activities of daily living or instrumental activities of daily living). Using the results of univariate analysis (P

As countries continue to industrialize, major cities experience diminished air quality, whereas rural populations also experience poor air quality from sources such as agricultural operations. These exposures to environmental pollution from both rural and populated/industrialized sources have adverse effects on human health. Although respiratory diseases (e.g., asthma and chronic obstructive pulmonary disease) are the most commonly reported following long-term exposure to particulate matter and hazardous chemicals, gastrointestinal complications have also been associated with the increased risk of lung disease from inhalation of polluted air. The interconnectedness of these organ systems has offered valuable insights into the roles of the immune system and the micro/mycobiota as mediators of communication between the lung and the gut during disease states. A topical example of this relationship is provided by reports of multiple gastrointestinal symptoms in patients with coronavirus disease 2019 (COVID-19), whereas the rapid transmission and increased risk of COVID-19 has been linked to poor air quality and high levels of particulate matter. In this review, we focus on the mechanistic effects of environmental pollution on disease progression with special emphasis on the gut-lung axis.

There is broad international consensus that ex ante regulation is needed to address the market dominance of the very largest digital platforms and that there are benefits to having broadly coherent regulatory approaches across jurisdictions. Regulation in any one jurisdiction will have extra-territorial effects, and inconsistent regulation will create unnecessary costs, reduce service quality, and dampen innovation. Greater coherency in the regulation of digital markets should make regulation more effective, more proportionate, and better able to limit any negative consequences. This article considers current US and EU proposals. We compare and contrast these two proposals through an economic lens, with a focus on substance rather than legal process and enforcement. We find substantial similarity of intent and approach between the US and EU proposals but also some important divergences, which highlight areas for further consideration by the EU and the US. We note in particular that the EU proposal does not include a provision analogous to a US proposal for strengthening the merger test applicable to acquisitions by large platforms, but that it should. More generally, the more the two sets of proposals can learn from each other, the better and more coherent the final regulations are likely to be.

New Experiments with Spheres-Gas (NEWS-G) is a dark matter direct detection experiment that will operate at SNOLAB (Canada). Similar to other rare-event searches, the materials used in the detector construction are subject to stringent radiopurity requirements. The detector features a 140-cm diameter proportional counter comprising two hemispheres made from commercially sourced 99.99% pure copper. Such copper is widely used in rare-event searches because it is readily available, there are no long-lived Cu radioisotopes, and levels of non-Cu radiocontaminants are generally low. However, measurements performed with a dedicated 210Po alpha counting method using an XIA detector confirmed a problematic concentration of 210Pb in bulk of the copper. To shield the proportional counter's active volume, a low-background electroforming method was adapted to the hemispherical shape to grow a 500-$��$m thick layer of ultra-radiopure copper to the detector's inner surface. In this paper the process is described, which was prototyped at Pacific Northwest National Laboratory (PNNL), USA, and then conducted at full scale in the Laboratoire Souterrain de Modane in France. The radiopurity of the electroplated copper was assessed through Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Measurements of samples from the first (second) hemisphere give 68% confidence upper limits of, 11 pages, 11 figures, 3 tables

This paper addresses interoperability a “super tool” to promote and preserve competition in digital platform markets where network effects are strong. As is widely acknowledged, these markets have an inherent tendency towards concentration, leaving consumers with little competition in the market. Mandated interoperability is a form of regulation that is less intrusive than many other forms and is particularly suited to digital business models and fast changing digital technology. We introduce the concept of “equitable interoperability,” which means that not only can an entrant join the platform, but it can join on qualitatively equal terms as others, without being discriminated against by the dominant platform that might have its own competing service. Carefully implemented, equitable interoperability breaks down entry barriers which paves the way for new entrants, which in turn creates competition and consumer choice. Interoperability transforms what might have been competition for the market into competition in the market, which is a more efficient and effective form of competition.

We analyze the use of the concepts of fairness and contestability in the Digital Markets Act (DMA) and propose formal definitions rooted in the economic analysis of digital markets as well as the goals of the proposed law. We discuss the implication of these concepts for innovation in digital markets.

Robot-assisted transabdominal preperitoneal inguinal hernia repair (rTAPP-IHR) is a safe and feasible approach for hernias of varying etiology. We aim to present a single surgeon's learning curve (LC) of this technique based on operative times, while accounting for bilaterality and complexity.This is a retrospective cohort analysis of patients who underwent rTAPP-IHR over a period of 5 years. Patients who underwent primary, recurrent, and complex (previous posterior repair, previous prostatectomy, scrotal, incarcerated) repairs were included. Cumulative and risk-adjusted cumulative sum analyses (CUSUM and RA-CUSUM) were used to depict the evolution of skin-to-skin times and complications/surgical site events (SSEs) with time, respectively.A total of 371 patients were included in the study. Mean skin-to-skin times were stratified according to four subgroups: unilateral non-complex (46.8 min), unilateral complex (63.2 min), bilateral non-complex (70.9 min), and bilateral complex (102 min). A CUSUM-LC was then plotted using each procedures difference in operative time from its subgroup mean. The peak of the plot occurred at case number 138, which was used as a transition between 'early' and 'late' phases. The average operative time for the late phase was 15.9 min shorter than the early phase (p 0.001). The RA-CUSUM, plotted using the weight of case complexity and unilateral/bilateral status, also showed decreasing SSE rates after the completion of 138 cases (early phase: 8.8% vs. late phase: 2.2%, p = 0.008). Overall complication rates did not differ significantly between the two phases.Our study shows that regardless of bilateral or complex status, rTAPP operative times and SSE rates gradually decreased after completing 138 procedures. Previous laparoscopic experience, robotic team efficiency, and surgical knowledge are important considerations for a surgeon's LC.

Background: Robotic Rives-Stoppa ventral hernia repair (rRS-VHR) is a minimally invasive technique that incorporates extraperitoneal mesh placement, using either transabdominal or totally extraperi...

BACKGROUND Cumulative sum (CUSUM) learning curves (LCs) are useful to analyze individual performance and to evaluate the acquisition of new skills and the evolution of those skills as experience is accumulated. The purpose of this study is to present a CUSUM LC based on the operative times of robotic intraperitoneal onlay mesh (rIPOM) ventral hernia repair (VHR) and identify differences observed throughout its phases. MATERIALS AND METHODS Patients who underwent rIPOM repair for elective, midline, and primary hernias were included. All procedures were performed exclusively by one surgeon within a 5-year period. CUSUM and risk-adjusted CUSUM were used to visualize the LC of rIPOM-VHR, based on operative times and complications. Once groups were obtained, univariate comparisons were performed. RESULTS Of the 90 rIPOM repairs, 25, 40, and 25 patients were allocated using a CUSUM analysis to the early, middle, and late phases, respectively. In terms of skin-to-skin times, the middle phase has a mean duration of 23 minutes shorter than the early phase (P

Fenestrated-branched endovascular aneurysm repair (FBEVAR) has expanded the treatment of patients with thoracoabdominal aortic aneurysms (TAAAs). Previous studies have demonstrated that women are less likely to be treated with standard infrarenal endovascular aneurysm repair because of anatomic ineligibility and experience greater mortality after both infrarenal and thoracic aortic aneurysm repair. The purpose of the present study was to describe the sex-related outcomes after FBEVAR for treatment of TAAAs.The data from 886 patients with extent I to IV TAAAs (excluding pararenal or juxtarenal aneurysms), enrolled in eight prospective, physician-sponsored, investigational device exemption studies from 2013 to 2019, were analyzed. All data were collected prospectively, audited and adjudicated by clinical events committees and/or data safety monitoring boards, and subject to Food and Drug Administration oversight. All the patients had been treated with Cook-manufactured patient-specific FBEVAR devices or the Cook t-Branch off-the-shelf device (Cook Medical, Brisbane, Australia).Of the 886 patients who underwent FBEVAR, 288 (33%) were women. The women had more extensive aneurysms and a greater prevalence of diabetes (33% vs 26%; P = .043) but a lower prevalence of coronary artery disease (33% vs 52%; P .0001) and previous infrarenal endovascular aneurysm repair (7.6% vs 16%; P .001). The women had required a longer operative time from incision to surgery end (5.0 ± 1.8 hours vs 4.6 ± 1.7 hours; P .001), experienced lower technical success (93% vs 98%; P = .002), and were less likely to be discharged to home (72% vs 83%; P = .009). Despite the smaller access vessels, the women did not have an increased incidence of access site complications. Also, the 30-day outcomes were broadly similar between the sexes. At 1 year, no differences were found between the women and men in freedom from type I or III endoleak (91.4% vs 92.0%; P = .64), freedom from reintervention (81.7% vs 85.3%; P = .10), target vessel instability (87.5% vs 89.2%; P = .31), and survival (89.6% vs 91.7%; P = .26). The women had a greater incidence of postoperative sac expansion (12% vs 6.5%; P = .006). Multivariable modeling adjusted for age, aneurysm extent, aneurysm size, urgent procedure, and renal function showed that patient sex was not an independent predictor of survival (hazard ratio, 0.83; 95% confidence interval, 0.50-1.37; P = .46).Women undergoing FBEVAR demonstrated metrics of increased complexity and had a lower level of technical success, especially those with extensive aneurysms. Compared with the men, the women had similar 30-day mortality and 1-year outcomes, with the exception of an increased incidence of sac expansion. These data have demonstrated that FBEVAR is safe and effective for women and men but that further efforts to improve outcome parity are indicated.

Objective The outcomes after open repair of thoracoabdominal aneurysms (TAAAs) have been definitively demonstrated to worsen as the TAAA extent increases. However, the effect of TAAA extent on fenestrated/branched endovascular aneurysm repair (F/BEVAR) outcomes is unclear. We investigated the differences in outcomes of F/BEVAR according to the TAAA extent. Methods We reviewed a single-institution, prospectively maintained database of all F/BEVAR procedures performed in an institutional review board-approved registry and/or physician-sponsored Food and Drug Administration investigational device exemption trial (trial no. G130210). The patients were stratified into two groups: group 1, extensive (extent 1-3) TAAAs; and group 2, nonextensive (juxtarenal, pararenal, and extent 4-5) TAAAs. The perioperative outcomes were compared using the χ2 test. Kaplan-Meier analysis of 3-year survival, target artery patency, reintervention, type I or III endoleak, and branch instability (type Ic or III endoleak, loss of branch patency, target vessel stenosis >50%) was performed. Cox proportional hazards modeling was used to assess the independent effect of extensive TAAA on 1-year mortality. Results During the study period, 299 F/BEVAR procedures were performed for 87 extensive TAAAs (29%) and 212 nonextensive TAAAs (71%). Most repairs had used company-manufactured, custom-made devices (n = 241; 81%). Between the two groups, no perioperative differences were observed in myocardial infarction, stroke, acute kidney injury, dialysis, target artery occlusion, access site complication, or type I or III endoleak (P > .05 for all). The incidence of perioperative paraparesis was greater in the extensive TAAA group (8.1% vs 0.5%; P = .001). However, the incidence of long-term paralysis was equivalent (2.3% vs 0.5%; P = .20), with nearly all patients with paraparesis regaining ambulatory function. On Kaplan-Meier analysis, no differences in survival, target artery patency, or freedom from reintervention were observed at 3 years (P > .05 for all). Freedom from type I or III endoleak (P Conclusions Unlike open TAAA repair, the F/BEVAR outcomes were similar for extensive and nonextensive TAAAs. The differences in perioperative paraparesis, branch instability, and type I or III endoleak likely resulted from the increasing length of aortic coverage and number of target arteries involved. These findings suggest that high-volume centers performing F/BEVAR should expect comparable outcomes for extensive and nonextensive TAAA repair.