Updates on coding in dermatology.

Correct coding is an important component of effective dermatology practice management. Over the past several years there have been updates to many commonly used codes within dermatology. This review highlights many of these updates, such as: the skin biopsy codes have been subdivided to reflect the different biopsy techniques. The definition of complex linear repairs has been updated and clarified. Outpatient and inpatient evaluation and management visits have new coding guidelines to determine level of care. Dermatopathology consultation codes have been updated and category III codes related to digital pathology have been created. Understanding the details and nuances of each of these categories of codes is vital to ensuring appropriate coding is performed.

On the genetic basis of tail-loss evolution in humans and apes.

The loss of the tail is among the most notable anatomical changes to have occurred along the evolutionary lineage leading to humans and to the 'anthropomorphous apes'1-3, with a proposed role in contributing to human bipedalism4-6. Yet, the genetic mechanism that facilitated tail-loss evolution in hominoids remains unknown. Here we present evidence that an individual insertion of an Alu element in the genome of the hominoid ancestor may have contributed to tail-loss evolution. We demonstrate that this Alu element-inserted into an intron of the TBXT gene7-9-pairs with a neighbouring ancestral Alu element encoded in the reverse genomic orientation and leads to a hominoid-specific alternative splicing event. To study the effect of this splicing event, we generated multiple mouse models that express both full-length and exon-skipped isoforms of Tbxt, mimicking the expression pattern of its hominoid orthologue TBXT. Mice expressing both Tbxt isoforms exhibit a complete absence of the tail or a shortened tail depending on the relative abundance of Tbxt isoforms expressed at the embryonic tail bud. These results support the notion that the exon-skipped transcript is sufficient to induce a tail-loss phenotype. Moreover, mice expressing the exon-skipped Tbxt isoform develop neural tube defects, a condition that affects approximately 1 in 1,000 neonates in humans10. Thus, tail-loss evolution may have been associated with an adaptive cost of the potential for neural tube defects, which continue to affect human health today.

Nickel-catalyzed ester carbonylation promoted by imidazole-derived carbenes and salts.

Millions of tons of acetyl derivatives such as acetic acid and acetic anhydride are produced each year. These building blocks of chemical industry are elaborated into esters, amides, and eventually polymer materials, pharmaceuticals, and other consumer products. Most acetyls are produced industrially using homogeneous precious metal catalysts, principally rhodium and iridium complexes. We report here that abundant nickel can be paired with imidazole-derived carbenes or the corresponding salts to catalyze methyl ester carbonylation with turnover frequency (TOF) exceeding 150 hour-1 and turnover number (TON) exceeding 1600, benchmarks that invite comparisons to state-of-the-art rhodium-based systems and considerably surpass known triphenylphosphine-based nickel catalysts, which operate with TOF ~7 hour-1 and TON ~100 under the same conditions.

Making ends meet - relating a self-reported indicator of financial hardship to health status.

BACKGROUND: Area-based index of multiple deprivation (IMD) indicators of financial hardship lack individual specificity and sensitivity. This study compared self-reports of hardship with area measures in relation to health status. METHODS: Interviews in one London Borough, reported financial hardship and health status. Associations of health status with most and least deprived quintiles of the IMD 2015 were compared with self-reported hardship; always or sometimes 'having difficulty making ends meet at the end of the month' in relation to never. RESULTS: 1024 interviews reported hardship status in 1001 (98%). 392 people (39%) reported they 'always' or 'sometimes' had hardship. In multivariate analysis, self-reported hardship was more strongly associated with smoking; odds ratio = 5.4 (95% CI: 2.8-10.4) compared with IMD, odds ratio = 1.9 (95% CI: 1.2-3.2). Health impairment was also more likely with self-reported hardship, odds ratio = 11.1 (95% CI: 4.9-25.4) compared with IMD; odds ratio = 2.7 (95% CI: 1.4-5.3). Depression was similarly related; odds ratio = 2.4 (95% CI: 1.0-5.6) and 2.7 (95% CI: 1.2-6.6), respectively. CONCLUSIONS: Self-reported hardship was more strongly related to health status than area-based indicators. Validity and implementation in routine health care settings remains to be established.

Tunable and Switchable Catalysis Enabled by Cation-Controlled Gating with Crown Ether Ligands.

ConspectusCatalysis has become an essential tool in science and technology, impacting the discovery of pharmaceuticals, the manufacture of commodity chemicals and plastics, the production of fuels, and much more. In most cases, a particular catalyst is optimized to mediate a particular reaction, continually producing a desired product at a given rate. There is enormous opportunity in developing catalysts that are dynamic, capable of responding to a change in the environment to alter structure and function. Controlled catalysis, in which the activity or selectivity of a catalytic reaction can be adjusted through an external stimulus, offers opportunities for innovation in catalysis. Catalyst discovery could be simplified if a single thoughtfully designed complex could work synergistically with additives to optimize performance rather than trying a multitude of different metal/ligand combinations. Temporal control could be gained to facilitate the execution of multiple reactions in the same flask, for example, by activating one catalyst and deactivating another to avoid incompatibilities. Selectivity switching could enable copolymer synthesis with well-defined chemical and material properties. These applications might sound futuristic for synthetic catalysts, but in nature, such a degree of controlled catalysis is commonplace. For example, allosteric interactions and/or feedback loops modulate enzymatic activity to enable complex small-molecule synthesis and sequence-defined polymerization reactions in complex mixtures containing many catalytic sites. In many cases, regulation is achieved by "gating" substrate access to the active site. Fundamental advances in catalyst design are needed to better understand the factors that enable controlled catalysis in the arena of synthetic chemistry, particularly in achieving substrate gating outside of macromolecular environments. In this Account, the development of design principles for achieving cation-controlled catalysis is described. The guiding hypothesis was that gating substrate access to a catalyst site could be achieved by controlling the dynamics of a hemilabile ligand through secondary Lewis acid/base and/or cation-dipole interactions. To enforce such interactions, catalysts sitting at the interface of organometallic catalysis and supramolecular chemistry were designed. A macrocyclic crown ether was incorporated into a robust organometallic pincer ligand, and these "pincer-crown ether" ligands have been explored in catalysis. Complementary studies of controlled catalysis and detailed mechanistic analysis guided the development of iridium, nickel, and palladium pincer-crown ether catalysts capable of substrate gating. Toggling the gate between open and closed states leads to switchable catalysis, where cation addition/removal changes the turnover frequency or the product selectivity. Varying the degree of gating leads to tunable catalysis, where the activity can be tuned based on the identity and amount of salt added. Research has focused on reactions of alkenes, particularly isomerization reactions, which has in turn led to design principles for cation-controlled catalysts.

Oxidative Addition of a Phosphinite P-O Bond at Nickel.

Oxidative addition is an essential elementary reaction in organometallic chemistry and catalysis. While a diverse array of oxidative addition reactions has been reported to date, examples of P-O bond activation are surprisingly rare. Herein, we report the ligand-templated oxidative addition of a phosphinite P-O bond in the diphosphinito aniline compound HN(2-OPiPr2-3,5-tBu-C6H2)2 [H(P2ONO)] at Ni0 to form (PONO)Ni(HPiPr2) after proton rearrangement. Notably, the P-O cleavage occurs selectively over an amine N-H bond activation. Additionally, the ligand cannibalization is reversible, as addition of XPR2 (X = Cl, Br; R = iPr, Cy) to (PONO)Ni(HPiPr2) readily produces either symmetric or unsymmetric (P2ONO)NiX species and free HPiPr2. Finally, the mechanisms of both the initial P-O bond cleavage and its subsequent reconstruction are investigated to provide further insight into how to target P-O bond activation.

The feminine and the transgender sinthome: clinical and theoretical issues / Feminino e sintoma transgênero: questões clínicas e teóricas / Féminin et sinthome transgenre: enjeux cliniques et théoriques / Feminino y síntoma transgénero: cuestiones clínicas y teóricas

In some contemporary psychoanalytic theories, a thesis has emerged according to which gender transition can constitute a sinthome. But gender remains a much-discussed notion in Lacanian psychoanalysis, especially in France. This article contributes to the debate by questioning the notion of femininity since it seems to be an essential point in how gender studies and Lacanian sexuation theory diverge. First, we clarify the Lacanian notion of femininity and its conceptual link to the notion of sinthome. Then, we discuss the clinical case of a transgender woman for whom the question of femininity was central during her transition. Finally, we argue how gender transition might function as a sinthome and the limits to such an understanding.

Em algumas teorias psicanalíticas contemporâneas, surgiu a tese de que a transição de gênero pode constituir um sinthoma. Mas gênero continua sendo uma noção muito discutida na psicanálise lacaniana, especialmente na França. Este artigo contribui para o debate ao questionar a noção de feminilidade, pois parece ser um ponto essencial na divergência entre os estudos de gênero e a teoria lacaniana da sexuação. Primeiramente, esclarecemos a noção lacaniana de feminilidade e seu vínculo conceitual com a noção de sinthoma. Em seguida, discutimos o caso clínico de uma mulher transgênero para quem a questão da feminilidade foi central durante sua transição. Por fim, discutimos como a transição de gênero pode funcionar como um sinthoma e os limites para tal compreensão.

Dans certaines théories psychanalytiques contemporaines, une thèse a émergé selon laquelle la transition de genre peut constituer un sinthome. Mais le genre reste une notion très discutée dans la psychanalyse lacanienne, notamment en France. Cet article contribue au débat en interrogeant la notion de féminité puisqu'elle semble être un point sur lequel divergent les études de genre et la théorie lacanienne de la sexuation. Pour ce faire, nous clarifions la notion lacanienne de féminité et son lien conceptuel avec la notion de sinthome. Ensuite, nous étudions le cas clinique d'une femme transgenre pour qui la question de la féminité a été centrale lors de sa transition. Enfin, nous discutons de la manière dont la transition de genre peut fonctionner comme un sinthome et des limites de cette thèse.

En algunas teorías psicoanalíticas contemporáneas ha surgido la tesis de que la transición de género puede constituir un sinthome. Pero el género sigue siendo una noción muy discutida en el psicoanálisis lacaniano, especialmente en Francia. Este artículo contribuye al debate cuestionando la noción de feminidad ya que parece ser un punto esencial en la divergencia entre los estudios de género y la teoría lacaniana de la sexuación. Primero, aclaramos la noción lacaniana de feminidad y su vínculo conceptual con la noción de sinthome. Luego, discutimos el caso clínico de una mujer transgénero para quien la cuestión de la feminidad fue central durante su transición. Finalmente, argumentamos cómo la transición de género podría funcionar como un sinthome y los límites de tal comprensión.

Procedural and anthropometric factors associated with musculoskeletal injuries among gastroenterology endoscopists.

BACKGROUND AND AIMS: Musculoskeletal (MSK) injuries among gastroenterologists are common. Our study describes risk factors and consequences of injury by comparing provider-specific anthropometric and objective procedural data to self-reported injury patterns. METHODS: A validated MSK symptom survey was sent to gastroenterologists to gauge prevalence, distribution, and severity of active injury. Respondents' procedural activities over 7 years were collected via an endoscopic database. RESULTS: 64 surveys were completed. 54 respondents had active pain; 53.1% reported activity-limiting injury. Activity-limiting injuries lead to longer colonoscopy times (25.3 vs. 22.1 min, P = 0.03) and lower procedural volumes (532 vs. 807, P = 0.01). Hand/wrist injuries yielded longer colonoscopy insertion times (9.35 vs. 8.21 min, P = 0.03) and less hands-on scope hours (81.2 vs. 111.7 h, P = 0.04). Higher esophagogastroduodenoscopy volume corelated with shoulder injury (336.5 vs. 243.1 EGDs/year, P = 0.04). Females had more foot injuries (P = 0.04). CONCLUSION: Activity-limiting MSK symptoms/injuries affect over 50% of endoscopists with negative impact on procedural volume and efficiency.

LINC00355 regulates p27KIP expression by binding to MENIN to induce proliferation in late-stage relapse breast cancer.

Late-stage relapse (LSR) in patients with breast cancer (BC) occurs more than five years and up to 10 years after initial treatment and has less than 30% 5-year relative survival rate. Long non-coding RNAs (lncRNAs) play important roles in BC yet have not been studied in LSR BC. Here, we identify 1127 lncRNAs differentially expressed in LSR BC via transcriptome sequencing and analysis of 72 early-stage and 24 LSR BC patient tumors. Decreasing expression of the most up-regulated lncRNA, LINC00355, in BC and MCF7 long-term estrogen deprived cell lines decreases cellular invasion and proliferation. Subsequent mechanistic studies show that LINC00355 binds to MENIN and changes occupancy at the CDKN1B promoter to decrease p27Kip. In summary, this is a key study discovering lncRNAs in LSR BC and LINC00355 association with epigenetic regulation and proliferation in BC.

Photochemical H2 Evolution from Bis(diphosphine)nickel Hydrides Enables Low-Overpotential Electrocatalysis.

Molecules capable of both harvesting light and forming new chemical bonds hold promise for applications in the generation of solar fuels, but such first-row transition metal photoelectrocatalysts are lacking. Here we report nickel photoelectrocatalysts for H2 evolution, leveraging visible-light-driven photochemical H2 evolution from bis(diphosphine)nickel hydride complexes. A suite of experimental and theoretical analyses, including time-resolved spectroscopy and continuous irradiation quantum yield measurements, led to a proposed mechanism of H2 evolution involving a short-lived singlet excited state that undergoes homolysis of the Ni-H bond. Thermodynamic analyses provide a basis for understanding and predicting the observed photoelectrocatalytic H2 evolution by a 3d transition metal based catalyst. Of particular note is the dramatic change in the electrochemical overpotential: in the dark, the nickel complexes require strong acids and therefore high overpotentials for electrocatalysis; but under illumination, the use of weaker acids at the same applied potential results in a more than 500 mV improvement in electrochemical overpotential. New insight into first-row transition metal hydride photochemistry thus enables photoelectrocatalytic H2 evolution without electrochemical overpotential (at the thermodynamic potential or 0 mV overpotential). This catalyst system does not require sacrificial chemical reductants or light-harvesting semiconductor materials and produces H2 at rates similar to molecular catalysts attached to silicon.

Apprising the choice of bariatric surgery in patients with compensated cirrhosis with morbid obesity: results of a national analysis.

Bariatric surgery (BS) was proved safe in carefully selected patients with compensated cirrhosis (CC). However, limited data exist on differential impact of bariatric surgery type on clinical outcomes and health care utilization. This retrospective study utilizes the 2010-2014 Nationwide Readmissions Database. We included obese adults with CC who underwent the two most commonly used BS, Roux-en-Y (RYGB) and laparoscopic sleeve gastrectomy (LSG). Those with decompensation within 6 months of BS were excluded. Rates of hepatic decompensation (new-onset ascites, variceal bleed, encephalopathy, spontaneous bacterial peritonitis, and/or hepatorenal syndrome), surgical complications, health care utilization, and mortality were compared between RYGB and LSG. Multivariable analysis was performed to fit various models. A total of 3032 patients with CC underwent BS, including 1864 (61.5%) RYGB and 1168 (38.5%) LSG. The majority (56%) of BS were performed at large, metropolitan teaching hospitals. There were no significant differences in various decompensations and surgical complications comparing RYGB to LSG. Healthcare utilization including index length of stay (RYGB: 3.4 days vs LSG: 3.0 days), 30-day readmission rate (RYGB: 9.5% vs LSG: 3.7%), and cost of admission (RYGB: $14,006 vs LSG: $12,523) were higher in RYGB (p values < 0.001). Index admission and calendar year mortality could not be analyzed due to the few number of events. Two types of bariatric surgeries in obese patients with compensated cirrhosis have similar rates of decompensated cirrhosis events and surgical complications. However, RYGB procedure incurred increased healthcare utilization. Therefore, LSG may be the preferred BS for patients with CC. Prospective, randomized studies comparing the types of BS are needed to confirm our observations.

Evidence-Based Clinical Practice Guideline: Reconstruction after Skin Cancer Resection.

SUMMARY: A multi-disciplinary work group involving stakeholders from various backgrounds and societies was convened to develop guidelines for the management of reconstruction after skin cancer resection. The goal was to identify areas of common ground and provide evidence-based recommendations to improve patient care. Given the heterogeneity of reconstructive techniques and clinical scenarios, investigation centered around common elements in the process. In some cases, a distinction was made between treatment options in the office-based setting as opposed to those in the facility setting. A systematic literature review was performed, and an established appraisal process was used to rate the quality of relevant scientific research (Grading of Recommendations Assessment, Development, and Evaluation methodology). Final recommendations are related to concepts concerning the timing of reconstruction, management of anticoagulation, use of antibiotics, methods of pain control, and follow-up assessment. At times, there was insufficient evidence to make high-level recommendations. The literature analysis highlights the need for additional methodologically robust studies in this area, to help guide clinical practice.

Evidence-based clinical practice guideline: Reconstruction after skin cancer resection.

A multi-disciplinary work group involving stakeholders from various backgrounds and societies was convened to develop guidelines for the management of reconstruction after skin cancer resection. The goal was to identify areas of common ground and provide evidence-based recommendations to improve patient care. Given the heterogeneity of reconstructive techniques and clinical scenarios, investigation centered around common elements in the process. In some cases, a distinction was made between treatment options in the office-based setting as opposed to those in the facility setting. A systematic literature review was performed, and an established appraisal process was used to rate the quality of relevant scientific research (Grading of Recommendations Assessment, Development, and Evaluation methodology). Final recommendations are related to concepts concerning the timing of reconstruction, management of anticoagulation, use of antibiotics, methods of pain control, and follow-up assessment. At times, there was insufficient evidence to make high-level recommendations. The literature analysis highlights the need for additional methodologically robust studies in this area, to help guide clinical practice.

Evidence-Based Clinical Practice Guideline: Reconstruction after Skin Cancer Resection.

SUMMARY: A multi-disciplinary work group involving stakeholders from various backgrounds and societies was convened to develop guidelines for the management of reconstruction after skin cancer resection. The goal was to identify areas of common ground and provide evidence-based recommendations to improve patient care. Given the heterogeneity of reconstructive techniques and clinical scenarios, investigation centered around common elements in the process. In some cases, a distinction was made between treatment options in the office-based setting as opposed to those in the facility setting. A systematic literature review was performed, and an established appraisal process was used to rate the quality of relevant scientific research (Grading of Recommendations Assessment, Development, and Evaluation methodology). Final recommendations are related to concepts concerning the timing of reconstruction, management of anticoagulation, use of antibiotics, methods of pain control, and follow-up assessment. At times, there was insufficient evidence to make high-level recommendations. The literature analysis highlights the need for additional methodologically robust studies in this area, to help guide clinical practice.

Postobesity Surgery Esophageal Dysfunction: A Combined Cross-Sectional Prevalence Study and Retrospective Analysis.

INTRODUCTION: Esophageal dysmotility including features of achalasia may develop because of bariatric surgery. However, the prevalence of these complications is unknown. We sought to define the prevalence of dysphagia and major esophageal motility disorders including achalasia after bariatric surgery through a large retrospective database review. METHODS: Patients with a history of laparoscopic sleeve gastrectomy or Roux-en-Y gastric bypass who underwent a diagnostic high-resolution impedance manometry (HRIM) either before or after bariatric surgery across 3 large tertiary referral sites from June 2012 through February 2019 were identified from a procedural database. HRIM studies were interpreted per the Chicago classification v3.0 by a blinded investigator (K.R.). Demographic/clinical features were collected. In addition, patients who underwent bariatric surgery from January 2014 to April 2015 were contacted and administered a validated symptom assessment survey to gauge the overall prevalence of dysphagia in a postbariatric population. RESULTS: A total of 137 patients were identified, including 97 who underwent HRIM after bariatric surgery (laparoscopic sleeve gastrectomy [n = 39, 40.1%]; Roux-en-Y gastric bypass [n = 58, 59.8%]) at a median of 5.84 years (interquartile range 2.1-12.5) postoperatively and 40 preoperative bariatric surgery candidates with medically complicated obesity. A manometric pattern consistent with achalasia was identified in 7 (7.2%) postsurgical patients compared with none in the preoperative group (P = 0.08). We further identified a separate achalasia-like pattern defined by aperistalsis and increased intragastric pressure (postobesity surgery esophageal dysfunction [POSED]) in 5 (5.2%) postsurgical patients vs none found preoperatively (P = 0.14). Achalasia or POSED was associated with postbariatric surgery (12.4% vs 0%, P = 0.02). Increasing time since surgery was independently associated with the development of achalasia (median 12.5 vs 5.8 years, P = 0.02), POSED (median 15.0 vs 5.8 years, P = 0.02) and major motility disorders (6.6 vs 4.9 years, P = 0.01). Furthermore, among 271 postbariatric surgery patients contacted for symptom assessment via survey, the prevalence of dysphagia was 13.7% at a mean 3.9 years after surgery. DISCUSSION: Postoperative dysphagia is a common long-term complication of bariatric surgery. This is potentially the consequence of a time-dependent association with the development of postoperative esophageal dysmotility, particularly achalasia and POSED. Consequently, esophageal dysmotility may be an important under-recognized complication of bariatric surgery.

Efficacy of Macular Hole Surgery in Patients with Idiopathic Macular Telangiectasia Type 2.

PURPOSE: To compare visual acuity (VA) and OCT outcomes in patients with idiopathic macular telangiectasia (IMT) type 2 who underwent pars plana vitrectomy (PPV) surgery for full-thickness macular holes (FTMHs) versus those who elected to be medically managed (MM) without surgery. DESIGN: Comparative retrospective case series. PARTICIPANTS: Patients with IMT type 2 and FTMH. METHODS: We reviewed records within an 11-year period and collected data on VA, OCT changes, development of choroidal neovascularization, and length of follow-up. The VA measurements were standardized from Snellen to logarithm of the minimum angle of resolution units for statistical analysis. Two-sample t tests were used to analyze VA data. OCT changes were assessed by a single masked retinal specialist. RESULTS: There were 12 eyes in the PPV group and 26 eyes in the MM group. There was no statistically significant VA improvement in either group between initial VA recording and last follow-up. The PPV group had no significant change in VA between the preoperative visit and the visits at 3 or 12 months. OCT scans improved by 1 step in 10 patients in the PPV group. None of the patients in the MM group had OCT improvement. Choroidal neovascularization developed in 1 eye in the PPV group and 5 eyes in the MM group. CONCLUSIONS: There was no significant change in VA in patients who opted to have PPV to treat their IMT type 2 and FTMH compared with those who did not undergo surgery. OCT scans improved by qualitative judgment in patients who underwent surgery compared with those who opted for medical management.

Decarbonylative ether dissection by iridium pincer complexes.

A unique chain-rupturing transformation that converts an ether functionality into two hydrocarbyl units and carbon monoxide is reported, mediated by iridium(i) complexes supported by aminophenylphosphinite (NCOP) pincer ligands. The decarbonylation, which involves the cleavage of one C-C bond, one C-O bond, and two C-H bonds, along with formation of two new C-H bonds, was serendipitously discovered upon dehydrochlorination of an iridium(iii) complex containing an aza-18-crown-6 ether macrocycle. Intramolecular cleavage of macrocyclic and acyclic ethers was also found in analogous complexes featuring aza-15-crown-5 ether or bis(2-methoxyethyl)amino groups. Intermolecular decarbonylation of cyclic and linear ethers was observed when diethylaminophenylphosphinite iridium(i) dinitrogen or norbornene complexes were employed. Mechanistic studies reveal the nature of key intermediates along a pathway involving initial iridium(i)-mediated double C-H bond activation.

Competency in esophagogastroduodenoscopy: a validated tool for assessment and generalizable benchmarks for gastroenterology fellows.

BACKGROUND AND AIMS: The Assessment of Competency in Endoscopy (ACE) tools for colonoscopy and EGD were both put forth by the Training Committee of the American Society for Gastrointestinal Endoscopy (ASGE), with the intent of providing teachers and programs a means to continuously assess fellow skills in these procedures throughout their years of training. Despite the availability of the tools, there are no data that define when competency in EGD has been reached. The goal of this study is to validate the EGD ACE tool (ACE-E) and for the first time describe learning curves and competency benchmarks for EGD by examining a large national cohort of trainees. METHODS: In a prospective, multicenter trial, gastroenterology fellows at all stages of training had their core cognitive and motor skills in EGDs assessed by staff using the ACE-E tool. Evaluations occurred at set intervals of every 50 procedures over an academic year. Like the previously reported and validated ACE tool for colonoscopy, the ACE-E tool uses a 4-point grading scale to define a skills continuum from novice to competent. At each assessment interval, average scores for each skill were computed and overall competency benchmarks for each skill were established using the contrasting groups method. RESULTS: Ninety-six GI fellows at 10 U.S. academic institutions had 1002 EGDs assessed using the ACE-E tool. Average ACE-E scores of 3.5 were found to be inclusive of all minimal competency thresholds identified for each core skill. In addition, independent intubation of the second part of the duodenum (D2) at rates of ≥95% as well as D2 intubation times of ≤4.75 minutes and average total procedure times of ≤12.5 minutes were identified as the points separating competent from non-competent groups. Although the average fellow achieves the D2 intubation rates and time criteria by 100 and 150 procedures, respectively, achieving ACE-E threshold scores on the remaining metrics was typically not achieved until 200 to 250 procedures. CONCLUSIONS: Nationally generalizable learning curves for EGD skills in GI fellows are described. Average ACE-E scores of 3.5, independent D2 intubation rates of 95%, and D2 intubation times of ≤4.75 minutes are recommended as minimum competency criteria. On average, it takes GI fellows only 150 procedures to simply drive the scope adequately but 250 procedures to achieve minimum competence in the remaining cognitive and motor skills. The D2 intubation rate threshold and learning curve found in this multicenter cohort using the ACE-E tool are similar to those recently described by researchers in the United Kingdom; however, development of cognitive and overall competence requires a higher procedure threshold than previously described.

Stabilization of Ruthenium(II) Polypyridyl Chromophores on Mesoporous TiO2 Electrodes: Surface Reductive Electropolymerization and Silane Chemistry.

Stabilization is a critical issue in the long term operation of dye-sensitized photoelectrosynthesis cells (DSPECs) for water splitting or CO2 reduction. The cells require a stable binding of the robust molecular chromophores, catalysts, and chromophore/catalyst assemblies on metal oxide semiconductor electrodes under the corresponding (photoelectro)chemical conditions. Here, an efficient stabilization strategy is presented based on functionalization of FTO|nanoTiO2 (mesoporous, nanostructured TiO2 deposited on fluorine-doped tin oxide (FTO) glass) electrodes with a vinylsilane followed by surface reductive electropolymerization of a vinyl-derivatized Ru(II) polypyridyl chromophore. The surface electropolymerization was dominated by a grafting-through mechanism, and rapidly completed within minutes. Chromophore surface coverages were controlled up to three equivalent monolayers by the number of electropolymerization cycles. The silane immobilization and cross-linked polymer network produced highly (photo)stabilized chromophore-grafted FTO|nanoTiO2 electrodes. The electrodes showed significant improvements over structures based on atomic layer deposition and polymer dip-coating stabilization methods in a wide pH range from pH ≈ 1 to pH ≈ 12.5 under both dark and light conditions. Under illumination, with hydroquinone added as a sacrificial electron transfer donor, a photoresponse for sustained electron transfer mediation occurred for at least ∼20 h in a pH ≈ 7.5 phosphate buffer (0.1 M NaH2PO4/Na2HPO4, with 0.5 M NaClO4). The overall procedure provides an efficient way to fabricate highly stabilized molecular assemblies on electrode surfaces with potential applications for DSPECs in solar fuels.