bluuebunny/crossref_metadata_2025 huggingface dataset:
Preselection algorithm based on predictive control for direct matrix converter
Authors: Dan Hanbing , Zhu Qi , Peng Tao , Yao Sun , Wheeler Patrick
Published: November 2016

This study presents an enhanced predictive control strategy to reduce the calculation effort for direct matrix converters. The main idea is to preselect the switching states to decrease the calculation effort during each sample period. The proposed preselection algorithm enables a predefined cost function to consider only the preselected switching states to perform the expected control. On the basis of the preselection of switching states at each sample period, the proposed method can effectively reduce the calculation effort as well as show a good performance. The proposed predictive control scheme uses only preselected switching states to generate the desired source/load current waveforms and control the input power factor. The feasibility of the proposed method is experimentally verified and results are presented in the study.
Active torque ripple reduction based on an analytical model of torque
Authors: Zhong Zaimin , Jiang Shang , Zhou Yingkun , Zhou Shuihua
Published: November 2016

The vibration caused by torque ripple may degrade the performance of drivetrain, thus the reduction of torque ripple are necessary for hybrid electrical vehicle/electrical vehicle application, while an analytical description of torque will be the basis. In this study, two‐dimensional Fourier series supplemented by polynomial fitting is introduced to reconstruct the numerical solution of magnetic coenergy (MCE) from finite element analysis. An analytical torque model, which can describe torque ripple precisely at all working points, is derived from the reconstructed MCE. On the basis of the torque model, the expressions of harmonic currents used to reduce torque ripple are obtained. The proposed expression also satisfies the principle of maximum torque per ampere. Then, a feedforward torque controller based on the expression of harmonic currents is introduced. Meanwhile, a feedback torque controller based on a torque observer is developed as a comparison. The results of simulation and experiments show that both two controllers can reduce the torque ripple in steady state, but the feedforward torque controller has obviously better effects when motor speed increases. Furthermore, the feedforward torque controller is also beneficial to decline torque ripple during transient process of torque response.
Finite control set predictive torque control for induction motor drive with simplified weighting factor selection using TOPSIS method
Authors: Muddineni Vishnu Prasad , Sandepudi Srinivasa Rao , Bonala Anil Kumar
Published: November 2016

Finite control set predictive torque control (FCS‐PTC) becomes popular for induction motor drives due to its simple structure and flexibility of including additional control parameters into the control law. However, primary concern of this control technique is the selection of suitable weighting factors in the cost‐function. Usually, empirical method is used to select the weighting factors, which is time‐consuming and heuristic process. In this study, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method is introduced in the cost‐function optimization to simplify the difficulties involved in the weighting factor selection. This method selects an optimal control action, which is closer to positive ideal control action and far away from negative ideal control action. This ensures the selection of optimal control action in each sampling period based on the priorities given to control parameters in the cost‐function. Further, to reduce the computational burden of proposed technique, a predefined set of switching states are used for the cost‐function optimization based on previous optimal control action. Both simulation and experimental studies are carried out for a two‐level voltage source inverter fed induction motor drive. These results are compared with conventional FCS‐PTC technique to highlight the merits of proposed technique.
Conventional and fuzzy PODCs for DFIG‐based wind farms and their impact on inter‐area and torsional oscillation damping
Authors: Ramirez‐Gonzalez Miguel , Malik Om , Castellanos‐Bustamante Rafael , Calderon‐Guizar Guillermo
Published: November 2016

Contribution to the damping of inter‐area and torsional oscillation modes, in doubly fed induction generators (DFIG) based wind farms, by power oscillation damping controllers (PODCs) based on two conventional structures and a fuzzy control strategy is investigated in this study. In this regard, a PODC with no lead/lag compensation is designed first and then a PODC with one lead/lag block is developed using eigenvalue techniques and the application of an iterative process based on the bat optimisation algorithm (BOA). Moreover, a fuzzy PODC, based on a simple fuzzy controller and tuned with the BOA according to the system transient response under a critical perturbation, is also designed. Comparative performance of the three PODCs is evaluated on a multi‐machine power system. It is observed that all three PODCs can contribute to improving the damping of inter‐area oscillations. However, eigenvalue analysis and non‐linear time domain simulations reveal that each of them may also impact to a lesser or greater extent the shaft torsional oscillation mode damping. Their relative impact in this regard is also investigated.
Internal breather-like wave generation by the second mode solitary wave interaction with a step
Authors: Terletska Kateryna , Jung Kyung Tae , Talipova Tatiana , Maderich Vladimir , Brovchenko Igor , Grimshaw Roger
Published: November 2016

The transformation of an internal second mode solitary wave over a bottom step in a computational tank filled with a three-layer stratified fluid was studied. The convex waveforms were generated by a collapse mechanism for stratification with a thin mid-layer. The wave transformation depends on the blocking parameter B which is a ratio of the amplitude of the incident wave to the thickness of the lower water layer over the step. Three regimes of second mode wave transformation over the step are identified. In regime I (2 < B < 6) this wave generates a breather-like internal wave (BLIW) packet behind the wave of mode-2 due to the impulse-like effect of the step and a long wave of mode-1 ahead of the wave. The BLIW degenerates into a dispersive wave packet at large B > 6. In regime II (0.5 < B < 2) the mode-2 wave is permanently disintegrated, generating a chain of waves of mode-1 ahead of wave of mode-2 and tail of short waves of mode-1 behind the wave. In regime III (B < 0.5) only waves of elevation of mode-1 penetrate into the fluid layer over the step.
Association of PD-1/PD-L axis expression with cytolytic activity, mutational load, and prognosis in melanoma and other solid tumors
Authors: Danilova Ludmila , Wang Hao , Sunshine Joel , Kaunitz Genevieve J. , Cottrell Tricia R. , Xu Haiying , Esandrio Jessica , Anders Robert A. , Cope Leslie , Pardoll Drew M. , Drake Charles G. , Taube Janis M.
Published: November 2016

Significance

The Cancer Genome Atlas datasets were used in the current study to explore the relationship of programmed death ligand-1 (PD-L1) expression, a cytotoxic T-cell gene signature, and mutational load to each other, to immunoactive factors, such as programmed cell death protein-1 (PD-1),PD-L2, and other checkpoint molecules, and to survival across multiple solid tumor types. We found thatPD-L2expression is more closely related to an ongoing host immune response in certain tumor types thanPD-L1. Notably, mutational load was not immediately related to inflammation in any tumor type studied, and was inferior to an inflamed tumor microenvironment for predicting survival in patients with metastatic melanoma. Our findings also indicate the need for biomarker assays that are tumor-type–specific and include both expression studies and genomic profiling.
Density of immunogenic antigens does not explain the presence or absence of the T-cell–inflamed tumor microenvironment in melanoma
Authors: Spranger Stefani , Luke Jason J. , Bao Riyue , Zha Yuanyuan , Hernandez Kyle M. , Li Yan , Gajewski Alexander P. , Andrade Jorge , Gajewski Thomas F.
Published: November 2016

Significance

The T-cell–inflamed tumor microenvironment correlates with efficacy of immunotherapy. It is critical to understand whether non–T-cell–inflamed tumors lack antigens for T-cell recognition. In melanoma, no difference between inflamed and noninflamed tumors for multiple antigen classes was observed. Synthesized peptides corresponding to predicted HLA-A2 binding epitopes showed no differences between inflamed and noninflamed tumors. Extrapolation of a T-cell signature across The Cancer Genome Atlas showed no correlation between gene expression and mutational burden in any cancer type. These results indicate that lack of spontaneous immune infiltration in solid tumors is unlikely to be due to lack of antigens. Rather, transcriptional profiling suggests lack of Batf3-lineage dendritic cells. Our data suggest that strategies to restore T-cell entry into noninflamed tumors should be developed.
Structural basis of N-Myc binding by Aurora-A and its destabilization by kinase inhibitors
Authors: Richards Mark W. , Burgess Selena G. , Poon Evon , Carstensen Anne , Eilers Martin , Chesler Louis , Bayliss Richard
Published: November 2016

Significance

Elevated levels of N-Myc protein (the product of the
MYCN
oncogene) drive cancers such as neuroblastoma. Accumulation of N-Myc in these cancer cells depends upon the formation of a complex with the protein kinase Aurora-A in which the N-Myc is not properly degraded. We mapped the region of N-Myc that interacts with Aurora-A and determined the molecular structure of the complex. Because this region also interacts with cellular machinery that targets N-Myc for degradation, we sought to understand the mechanism by which N-Myc stabilizes Aurora-A. The structure explains how compounds that induce distorted conformations of Aurora-A are able to disrupt the interaction with N-Myc. This understanding may provide a basis for designing better compounds that work in this way for the treatment of neuroblastoma.
Two proofreading steps amplify the accuracy of genetic code translation
Authors: Ieong Ka-Weng , Uzun Ülkü , Selmer Maria , Ehrenberg Måns
Published: November 2016

Significance

We have discovered that two proofreading steps amplify the accuracy of genetic code reading, not one step, as hitherto believed. We have characterized the molecular basis of each one of these steps, paving the way for structural analysis in conjunction with structure-based standard free energy computations. Our work highlights the essential role of elongation factor Tu for accurate genetic code translation in both initial codon selection and proofreading. Our results have implications for the evolution of efficient and accurate genetic code reading through multistep proofreading, which attenuates the otherwise harmful effects of the obligatory tradeoff between efficiency and accuracy in substrate selection by enzymes.
Chloroplast division checkpoint in eukaryotic algae
Authors: Sumiya Nobuko , Fujiwara Takayuki , Era Atsuko , Miyagishima Shin-ya
Published: November 2016

Significance

Chloroplasts arose from a cyanobacterial endosymbiont, which introduced photosynthesis into eukaryotes. It is widely believed that synchronization of division in the eukaryotic host cell and in the endosymbiont was critical for the host cell to maintain the endosymbiont/chloroplast permanently. However, it is unclear how the division of the endosymbiont (the chloroplast) and host cell became synchronized. Using the unicellular red alga
Cyanidioschyzon merolae
, we show that the host cell enters into the metaphase only when chloroplast division has commenced. A similar phenomenon also was observed in the glaucophyte alga
Cyanophora paradoxa
. It thus seems likely that the acquisition of the cell-cycle checkpoint of chloroplast division played an important role in the establishment of the chloroplast in ancient algae.
The double identity of linguistic doubling
Authors: Berent Iris , Bat-El Outi , Brentari Diane , Dupuis Amanda , Vaknin-Nusbaum Vered
Published: November 2016

Significance

Across languages, certain linguistic forms are systematically preferred to others (e.g.,
blog
>
lbog
), but whether such preferences reflect abstract linguistic principles or the sensorimotor demands associated with the encoding of linguistic stimuli is unknown. To inform this debate, here we examine whether the preferences for linguistic forms can be disentangled from their sensorimotor characteristics. Our results demonstrate that people’s linguistic preferences doubly dissociate from the demands exacted by the linguistic stimulus: A single stimulus can elicit diverse percepts, whereas each such percept can remain invariant despite radical changes to stimulus modality—speech and signs. These conclusions are in line with the possibility that linguistic principles are amodal and abstract.
Catheter-Based Renal Denervation for Resistant Hypertension: Will It Ever Be Ready for “Prime Time”?
Authors: Laffin Luke J , Bakris George L
Published: November 2016

The year 2014 was a turning point for the field of renal denervation (RDN) and its potential use to treat resistant hypertension. Tremendous enthusiasm shifted to sober reflection on the efficacy of a technology once touted as the cure to resistant hypertension. The following review highlights 2 major questions: First, does catheter-based RDN lower blood pressure and, second, will RDN using catheter-directed therapy for the treatment of resistant hypertension ever become more than an investigational technology.
Shark finning in eastern Indonesia: assessing the sustainability of a data-poor fishery
Authors: Jaiteh Vanessa F. , Hordyk Adrian R. , Braccini Matías , Warren Carol , Loneragan Neil R.
Published: November 2016

For over two decades, Indonesia has reported higher average shark landings than any other nation, but very little local information exists on the fishery and life histories of targeted species. This poses severe challenges to shark sustainability and conservation in this vast archipelago. We draw on diverse sources of data to evaluate the sustainability of the shark fishery in eastern Indonesia, a particularly data-poor region where sharks are primarily targeted for their fins. Shark fishers from three coastal communities were interviewed on their perceptions of catch trends over the past twenty years and asked to collect fishing data during fishing trips in the Seram, Arafura and Timor Seas. For the most frequently harvested species, we estimated maximum intrinsic rates of increase (rmax) to predict their resilience to fishing pressure. Our results indicate that shark fishing practices in the region are likely to be unsustainable. The catches of several species largely comprised of immature individuals and most fishers attributed observed declines in shark numbers, size and species diversity to overfishing. Hammerhead sharks have relatively high intrinsic resilience but are nevertheless at risk of local extinction due to their availability to the fishery and the value of their fins. Sandbar, dusky and grey reef sharks have lower resilience and are frequently caught but not managed. We recommend a composite management approach, including consistent implementation of existing trade restrictions, fisheries research and opportunities for fishers’ livelihood diversification, to stem shark harvests in eastern Indonesia.
Safety and Efficacy of Anidulafungin for Fungal Infection in Patients With Liver Dysfunction or Multiorgan Failure
Authors: Verma Anita , Auzinger Georg , Kantecki Michal , Campling James , Spurden Dean , Percival Fran , Heaton Nigel
Published: November 2016

Background

The objective of this study was to review our clinical experience on the safety and efficacy of anidulafungin, an echinocandin antifungal, in the treatment of invasive fungal infections (IFIs) in patients with moderate to severe abnormal liver function tests or multiorgan failure and IFI, in a large United Kingdom Liver Centre.

Methods

The clinical records of the first 50 consecutive patients treated for IFI with anidulafungin between January 7, 2009 and March 2, 2011 were analyzed. Data were collected on demographics, underlying disease, disease characteristics, hematological and biochemical parameters, IFI, concomitant bacterial and viral infections, response to anidulafungin, and anidulafungin-related adverse events.

Results

The patients’ median age was 54.3 years (range, 19.6–75.9); 60% were male. Twenty-two (44%) patients were liver transplant recipients. Others had hepatopancreaticobiliary disease (n = 15, 30%) or chronic liver disease (n = 11, 22%). Invasive fungal infection (predominantly Candida spp) was proven in 36 (72%) patients, probable in 14 (28%). Of 46 evaluable patients, 35 (76%) had a favorable anidulafungin treatment outcome. Forty-nine (98%) had abnormal liver function tests (LFTs) pretreatment; 31 (62%) had ≥1 LFT raised to ≥2× baseline during anidulafungin treatment.

Conclusions

In this highly specialized group of patients, anidulafungin treatment was efficacious and well tolerated by those with decompensated liver disease, multiorgan failure, and high-risk liver transplant with proven or probable IFI.
Closed Reduction for Developmental Dysplasia of the Hip: Early-term Results From a Prospective, Multicenter Cohort
Authors: Sankar Wudbhav N. , Gornitzky Alex L. , Clarke Nicholas M.P. , Herrera-Soto José A. , Kelley Simon P. , Matheney Travis , Mulpuri Kishore , Schaeffer Emily K. , Upasani Vidyadhar V. , Williams Nicole , Price Charles T.
Published: November 2016

Background:

Closed reduction (CR) is a common treatment for infantile developmental dysplasia of the hip. The purpose of this observational, prospective, multicenter study was to determine the early outcomes following CR.

Methods:

Prospectively collected data from an international multicenter study group was analyzed for patients treated from 2010 to 2014. Baseline demographics, clinical exam, radiographic/ultrasonographic data, and history of previous orthotic treatment were assessed. At minimum 1-year follow-up, failure was defined as an IHDI grade 3 or 4 hip and/or need for open reduction. The incidence of avascular necrosis (AVN), residual dysplasia, and need for further surgery was assessed.

Results:

A total of 78 patients undergoing CR for 87 hips were evaluated with a median age at initial reduction of 8 months (range, 1 to 20 mo). Of these, 8 hips (9%) were unable to be closed reduced initially. At most recent follow-up (median 22 mo; range, 12 to 36 mo), 72/79 initially successful CRs (91%) remained stable. The likelihood of failure was unaffected by initial clinical reducibility of the hip (P=0.434), age at initial CR (P=0.897), or previous treatment in brace (P=0.222). Excluding those hips that failed initial CR, 18/72 hips (25%) developed AVN, and the risk of osteonecrosis was unaffected by prereduction reducibility of the hip (P=0.586), age at CR (P=0.745), presence of an ossific nucleus (P=0.496), or previous treatment in brace (P=0.662). Mean acetabular index on most recent radiographs was 25 degrees (±6 degrees), and was also unaffected by any of the above variables. During the follow-up period, 8/72 successfully closed reduced hips (11%) underwent acetabular and/or femoral osteotomy for residual dysplasia.

Conclusions:

Following an initially successful CR, 9% of hips failed reduction and 25% developed radiographic AVN at early-term follow-up. History of femoral head reducibility, previous orthotic bracing, and age at CR did not correlate with success or chances of developing AVN. Further follow-up of this prospective, multicenter cohort will be necessary to establish definitive success and complication rates following CR for infantile developmental dysplasia of the hip.

Level of Evidence:

Level II—prospective observational cohort.
Meat and haem iron intake in relation to glioma in the European Prospective Investigation into Cancer and Nutrition study
Authors: Ward Heather A. , Gayle Alicia , Jakszyn Paula , Merritt Melissa , Melin Beatrice , Freisling Heinz , Weiderpass Elisabete , Tjonneland Anne , Olsen Anja , Dahm Christina C. , Overvad Kim , Katzke Verena , Kühn Tilman , Boeing Heiner , Trichopoulou Antonia , Lagiou Pagona , Kyrozis Andreas , Palli Domenico , Krogh Vittorio , Tumino Rosario , Ricceri Fulvio , Mattiello Amalia , Bueno-de-Mesquita Bas , Peeters Petra H. , Quirós José Ramón , Agudo Antonio , Rodriguez-Barranco Miguel , Larrañaga Nerea , Huerta José M. , Barricarte Aurelio , Sonestedt Emily , Drake Isabel , Sandström Maria , Travis Ruth C. , Ferrari Pietro , Riboli Elio , Cross Amanda J.
Published: November 2016

Diets high in red or processed meat have been associated positively with some cancers, and several possible underlying mechanisms have been proposed, including iron-related pathways. However, the role of meat intake in adult glioma risk has yielded conflicting findings because of small sample sizes and heterogeneous tumour classifications. The aim of this study was to examine red meat, processed meat and iron intake in relation to glioma risk in the European Prospective Investigation into Cancer and Nutrition study. In this prospective cohort study, 408 751 individuals from nine European countries completed demographic and dietary questionnaires at recruitment. Multivariable Cox proportional hazards models were used to examine intake of red meat, processed meat, total dietary iron and haem iron in relation to incident glioma. During an average follow-up of 14.1 years, 688 incident glioma cases were diagnosed. There was no evidence that any of the meat variables (red, processed meat or subtypes of meat) or iron (total or haem) were associated with glioma; results were unchanged when the first 2 years of follow-up were excluded. This study suggests that there is no association between meat or iron intake and adult glioma. This is the largest prospective analysis of meat and iron in relation to glioma and as such provides a substantial contribution to a limited and inconsistent literature.
Usefulness of the Clavien–Dindo Classification in Understanding the Limitations and Indications of Larynx-preserving Esophageal Reconstruction
Authors: Umezawa Hiroki , Nakao Junichi , Matsutani Takeshi , Kuwahara Hiroaki , Taga Marie , Ogawa Rei
Published: November 2016

Background:

The Clavien–Dindo (CD) classification is used to evaluate the severity of surgical complications. However, its usefulness in esophageal reconstruction has not been reported. To address this, this case series study used the CD classification to evaluate the complications after cervical esophageal reconstruction with free jejunum transfer or supercharged pedicled intestinal transfer.

Methods:

All consecutive patients who underwent esophageal cancer surgery with larynx-preserving free jejunum or pedicled ileocolic transfer in June 2012–December 2015 were identified. The postoperative complications were classified using the CD classification.

Results:

In total, 22 patients (20 men and 2 women; mean age, 63.3 years) underwent esophageal cancer reconstruction with larynx-preserving free jejunum transfer (n = 9) and supercharged pedicled intestinal transfer (n = 13). Seven patients underwent prophylactic tracheotomy. Four patients underwent emergent tracheotomy 1 or 5 days after surgery. The most frequent complication was recurrent nerve paralysis (RNP) (n = 8). Of these 8 RNP cases, 6 and 2 were classified as CD I and III complications, respectively. Pneumonia was the next most common complication (n = 7). Of these 7 pneumonia cases, 5 and 2 were classified as CD II and III, respectively. There were 2 cases of intestinal anastomosis leakage (CD II and III). On average, patients were able to start oral alimentation 15.1 (9–35) days after surgery.

Conclusions:

Our analysis with the CD classification suggested that vascularized free jejunum transfer or supercharge-drainage pedicled ileocolic transfer prevents postoperative intestinal anastomosis leakage and that prophylactic tracheotomy is especially indicated in cases with significant surgical damage in the cervical region.
Carotid Intima-Media Thickness as a Cardiovascular Risk Factor and Imaging Pathway of Atherosclerosis
Authors: Centurión Osmar Antonio
Published: November 2016

Assessment of carotid intima-media thickness (IMT) has emerged as a simple and noninvasive technique for measuring atherosclerotic burden. Although serum biomarkers have been linked to the risk of developing atherosclerosis, carotid IMT has the theoretical advantage of directly visualizing a final consequence of the disease itself, namely atherosclerosis in the vessel wall. The current widespread application of carotid IMT measurements has been based on the validity, standardization, and reproducibility of the measurement and the evidence that an increased carotid IMT can be regarded as an attractive biomarker of atherosclerosis and of increased cardiovascular risk, potentially useful as a therapeutic target in those at increased cardiovascular risk. The utilization of carotid IMT measurements as a surrogate end point in clinical trials evaluating a specific drug intervention may result in considerably smaller efforts and costs than when using a hard end point such as myocardial infarction, stroke, or death. In addition, the use of carotid IMT measurement as a screening tool in clinical practice in association with traditional risk factors may improve risk classification and decisions regarding therapeutic interventions. However, although carotid IMT may be correlated with clinical outcomes, changes in surrogate end points over time that result from a particular therapy may not necessarily be predictive of future cardiovascular events. Therefore, it is necessary to perform more clinical studies to clearly define the relationship between the modifications in carotid IMT and the changes in cardiovascular events. In an era of economic burden, when there is a clear combination of limited resources with high expense of innovation in drug development, carotid IMT represents a reasonable, worthwhile surrogate trial end point with a history of nearly 30 years of technical progress and clinical research. Current data strongly suggest that carotid IMT will continue to successfully be used as a valuable tool in clinical atherosclerosis research.
A Novel Pretreatment Regimen for Breakthrough Radiocontrast Media Anaphylaxis in Cardiac Patients
Authors: Montandon Shari V. , Petrov Andrej A. , Fajt Merritt L.
Published: November 2016

Background:

Radiocontrast media allergy is a severe and potentially life-threatening condition. This creates a clinical dilemma for cardiac patients who require urgent interventions with radiocontrast media. Several pretreatment regimens have been suggested for patients with prior immediate hypersensitivity reactions to radiocontrast media. Despite using pretreatment regimens, breakthrough reactions have been reported in 2.1%–18% of patients with radiocontrast media allergy. Little is known about management of patients with a history of breakthrough radiocontrast media anaphylaxis who require urgent lifesaving procedures.

Methods:

We report a retrospective analysis of 2 cardiac cases with a history of breakthrough radiocontrast media anaphylaxis despite standard pretreatment. These patients required urgent cardiac intervention with the use of radiocontrast media.

Results:

We present a novel pretreatment regimen for high-risk cardiac patients with breakthrough radiocontrast media anaphylaxis despite prior pretreatment who need urgent coronary interventions.

Conclusion:

This protocol is both safe and effective in mitigating anaphylaxis in cardiac patients.
Chest Pain Risk Scores Can Reduce Emergent Cardiac Imaging Test Needs With Low Major Adverse Cardiac Events Occurrence in an Emergency Department Observation Unit
Authors: Wang Hao , Watson Katherine , Robinson Richard D. , Domanski Kristina H. , Umejiego Johnbosco , Hamblin Layton , Overstreet Sterling E. , Akin Amanda M. , Hoang Steven , Shrivastav Meena , Collyer Michael , Krech Ryan N. , Schrader Chet D. , Zenarosa Nestor R.
Published: November 2016

Objective:

To compare and evaluate the performance of the HEART, Global Registry of Acute Coronary Events (GRACE), and Thrombolysis in Myocardial Infarction (TIMI) scores to predict major adverse cardiac event (MACE) rates after index placement in an emergency department observation unit (EDOU) and to determine the need for observation unit initiation of emergent cardiac imaging tests, that is, noninvasive cardiac stress tests and invasive coronary angiography.

Methods:

A prospective observational single center study was conducted from January 2014 through June 2015. EDOU chest pain patients were included. HEART, GRACE, and TIMI scores were categorized as low (HEART ≤ 3, GRACE ≤ 108, and TIMI ≤1) versus elevated based on thresholds suggested in prior studies. Patients were followed for 6 months postdischarge. The results of emergent cardiac imaging tests, EDOU length of stay (LOS), and MACE occurrences were compared. Student t test was used to compare groups with continuous data, and χ2 testing was used for categorical data analysis.

Results:

Of 986 patients, emergent cardiac imaging tests were performed on 62%. A majority of patients were scored as low risk by all tools (85% by HEART, 81% by GRACE, and 80% by TIMI, P < 0.05). The low-risk patients had few abnormal cardiac imaging test results as compared with patients scored as intermediate to high risk (1% vs. 11% in HEART, 1% vs. 9% in TIMI, and 2% vs. 4% in GRACE, P < 0.05). The average LOS was 33 hours for patients with emergent cardiac imaging tests performed and 25 hours for patients without (P < 0.05). MACE occurrence rate demonstrated no significant difference regardless of whether tests were performed emergently (0.31% vs. 0.97% in HEART, 0.27% vs. 0.95% in TIMI, and 0% vs. 0.81% in GRACE, P > 0.05).

Conclusions:

Chest pain risk stratification via clinical decision tool scores can minimize the need for emergent cardiac imaging tests with less than 1% MACE occurrence, especially when the HEART score is used.
Novel Emergency Department Risk Score Discriminates Acute Coronary Syndrome Among Chest Pain Patients With Known Coronary Artery Disease
Authors: Crim Matthew T. , Berkowitz Scott A. , Saheed Mustapha , Miller Jason , Deutschendorf Amy , Gerstenblith Gary , Hill Peter , Korley Frederick K.
Published: November 2016

Background:

Patients with known coronary artery disease presenting to the emergency department (ED) with chest pain are often admitted, yet may not be having an acute coronary syndrome (ACS).

Methods:

We assessed whether the use of a novel risk score and a modified thrombolysis in myocardial infarction risk score obtained in the ED could discriminate which of these high-risk patients have ACS. Chart review was performed on a cohort of 285 patients with known coronary artery disease presenting to the ED with chest pain thought to be of ischemic origin and admitted to the hospital. The ED variables were assessed with logistic regression for their association with eventual ACS diagnosis at hospital discharge. ACS was diagnosed in 74 (26%) of the patients.

Results:

Non-ACS patients had a 2-day median length of stay and $6875 median inpatient (post ED) hospital charges (not including physician fees), totaling 566 hospital bed days and $1,871,250 for the 211 (74%) non-ACS patients. A novel risk score, including (1) history of prior revascularization, (2) comorbid chronic kidney disease, (3) onset of chest discomfort at rest, (4) dynamic electrocardiogram changes in the ED, (5) elevated troponin I (>0.05 ng/mL) in the ED, and (6) associated illness at presentation, discriminated ACS and non-ACS with a c statistic of 0.767; the c statistic for a modified thrombolysis in myocardial infarction risk score was 0.712.

Conclusions:

Application of these risk scores may reduce the number of potentially avoidable admissions and their associated hazards and costs.
Association Between Hospital Practices and Door-in-door-out Time in ST-segment Elevation Myocardial Infarction
Authors: Mumma Bryn E. , Eggert James , Mahler Simon A. , Kontos Michael C. , Diercks Deborah B.
Published: November 2016

Background:

Current guidelines suggest a “door-in-door-out” (DIDO) time of 30 minutes or shorter for patients with ST-segment elevation myocardial infarction (STEMI) who arrive at a STEMI referral hospital and are transferred to a STEMI-receiving center for primary percutaneous coronary intervention. Experts previously identified 18 system practices as critical for reducing DIDO times. The objective of this study was to describe how frequently these critical practices are used and to determine whether their use was associated with shorter DIDO times.

Methods:

We surveyed 18 STEMI referral hospitals for 4 STEMI-receiving centers regarding their use of these 18 practices. The median number used was 14 practices (interquartile range 12–15). We then evaluated their association with DIDO times in all patients (n = 93) transferred from these STEMI referral hospitals to the 4 STEMI-receiving centers for primary percutaneous coronary intervention.

Results:

In univariate linear regression analyses, system-wide quality improvement programs with leaders in the emergency medical services agencies and STEMI referral hospitals were associated with shorter DIDO times (P < 0.001 for all). Overall use of system practices was not associated with DIDO times (P = 0.143). The majority (76%, 95% confidence interval: 66%–85%) of DIDO times did not meet the 30-minute goal.

Conclusions:

These findings highlight the difficulty in achieving the 30-minute DIDO goal and the need for continued focus on strategies for reducing DIDO time, including system-wide quality improvement programs.
Optic Nerve Head Histopathology in High Axial Myopia
Authors: Jonas Jost B. , Ohno-Matsui Kyoko , Panda-Jonas Songhomitra
Published: November 2016

Purpose:

To describe particularities of the optic nerve head of axially highly myopic eyes.

Methods:

Measurements were obtained from enucleated globes and from population-based studies.

Results:

Morphologic optic disc particularities in high axial myopia included enlarged disc size (secondary macrodisc), widening and temporal translocation of the papillary Bruch’s membrane (BM) opening, parapapillary gamma and delta zone, elongation and thinning of lamina cribrosa and peripapillary scleral flange, steeper translamina cribrosa pressure gradient, decreased peripapillary choroid thickness, longer distance between peripapillary arterial circle and optic disc, optic cup flattening, presumably a stretching of the lamina cribrosa pores, and peripapillary intrachoroidal cavitations. These changes may be explained by growth of new BM in the retroequatorial region in the process of emmetropization or myopization as “overshooting” of the emmetropization process.

Conclusions:

The intrapapillary and parapapillary changes in the highly myopic optic nerve head may be reason for the increased susceptibility for glaucomatous optic nerve damage in high axial myopia. The widening of the papillary BM opening and the potential shift of the optic nerve head’s 3 layer into temporal direction, both potentially leading to the development of parapapillary gamma zone may be of interest for elucidating the process of emmetropization/myopization.
Linkage to Primary Care and Survival After Hospital Discharge for HIV-Infected Adults in Tanzania: A Prospective Cohort Study
Authors: Peck Robert N. , Wang Richard J. , Mtui Graham , Smart Luke , Yango Missana , Elchaki Rim , Wajanga Bahati , Downs Jennifer A. , Mteta Kien , Fitzgerald Daniel W.
Published: November 2016

Introduction:

Little is known about outcomes after hospitalization for HIV-infected adults in sub-Saharan Africa. We determined 12-month, posthospital mortality rates in HIV-infected vs. uninfected adults and predictors of mortality.

Methods:

In this prospective cohort study, we enrolled adults admitted to the medical wards of a public hospital in northwestern Tanzania. We conducted standardized questionnaires, physical examinations, and basic laboratory analyses including HIV testing. Participants or proxies were called at 1, 3, 6, and 12 months to determine outcomes. Predictors of in-hospital and posthospital mortality were determined using logistic regression. Cox regression models were used to analyze mortality incidence and associated factors. To confirm our findings, we studied adults admitted to another government hospital.

Results:

We enrolled 637 consecutive adult medical inpatients: 38/143 (26.6%) of the HIV-infected adults died in hospital vs. 104/494 (21.1%) of the HIV-uninfected adults. Twelve-month outcomes were determined for 98/105 (93.3%) vs. 352/390 (90.3%) discharged adults, respectively. Posthospital mortality was 53/105 (50.5%) for HIV-infected adults vs. 126/390 (32.3%) for HIV-uninfected adults (adjusted P = 0.006). The 66/105 (62.9%) HIV-infected adults who attended clinic within 1 month after discharge had significantly lower mortality than the other HIV-infected adults [adjusted hazards ratio = 0.17 (0.07–0.39), P < 0.001]. Adults admitted to a nearby government hospital had similar high rates of posthospital mortality.

Conclusions:

Posthospital mortality is disturbingly high among HIV-infected adult inpatients in Tanzania. The posthospital period may offer a window of opportunity to improve survival in this population. Interventions are urgently needed and should focus on increasing posthospital linkage to primary HIV care.
Single-Incision Laparoscopic Appendectomy by Surgical Trainees
Authors: Suh Sang Gyun , Sohn Hee Joo , Kim Beom Gyu , Park Joong-Min , Choi Yoo-Shin , Park Yong Keum , Lee Seung Eun
Published: November 2016

Background:

Single-incision laparoscopic appendectomy (SILA) is one of the most commonly performed single port surgeries in the world. However, there are few publications documenting a young resident’s experience. The purpose of this study is to investigate clinical outcomes of SILA performed by a surgical trainee and to evaluate its feasibility and safety compared with conventional three-port laparoscopic appendectomy (TPLA) when performed by a surgical trainee and SILA by surgical staff.

Methods:

Between September 2014 and August 2015, clinical data were retrospectively collected for SILA and TPLA cases performed at Chung-Ang University Hospital. Three surgical residents who have assisted at least 50 cases of TPLA and 30 cases of SILA performed by gastrointestinal surgery specialists performed the surgeries. The indication of SILA by surgical trainees was noncomplicated appendicitis with no comorbidity.

Results:

In total, 47 patients underwent SILA by surgical residents, 98 patients underwent TPLA by surgical residents and 137 patients underwent SILA by surgical staff. In comparing SILA and TPLA performed by surgical residents, the mean age was younger (26 vs. 41 y, P<0.005) in the SILA group, the operative time (47.2 vs. 61.5 min, P<0.010) and hospital stay (2.3 vs. 2.7 d, P=0.003) were shorter in SILA group. In the SILA group, 2 cases of postoperative fluid collection (5.7%) occurred, necessitating antibiotic treatment. In TPLA group, 1 postoperative abscess occurred, requiring drainage. When comparing SILA performed by surgical residents and SILA performed by surgical staff, there were no significant differences in operation time, and postoperative complications.

Conclusion:

Surgical residents safely performed SILA with good postoperative outcomes after short learning curve.
Cause for pause before leaping to conclusions about stepping
Authors: Zylberberg Ariel , Shadlen Michael N.
Published: November 2016

Many neurons in parietal and prefrontal association cortex undergo gradual changes in firing rate during the formation of some perceptual decisions. These dynamics are often ramp-like increases or decreases depending on the sign and strength of the sensory evidence and are thus hypothesized to represent the accumulation of noisy samples of evidence, analogous to biased diffusion. This idea was challenged recently. An analysis of sequences of action potentials recorded from neurons in the lateral intraparietal cortex (area LIP) suggests that the spikes on single trials are explained by rates that undergo a discrete step from an intermediate rate to either a low or high rate at a random time during deliberation. The average of such steps, like the average of biased diffusion, is consistent with the ramp-like firing rates observed in LIP, but a Bayesian model comparison deemed stepping superior. Here we show that a shortcoming in the mathematical depiction of drift-diffusion led to a severe bias in the model comparison. We conclude that at present there is no compelling evidence that favors the stepping account.
A TOPOLOGICAL/ECOLOGICAL APPROACH TO PERCEPTION
Authors: Tozzi Arturo , Peters James , Ramanna Sheela
Published: November 2016

During the exploration of the surrounding environment, the brain links together external inputs, giving rise to perception of a persisting object. During imaginative processes, the same object can be recalled in mind even if it is out of sight. In this proof of concept study, Borsuk's theory of shape and the Borsuk-Ulam theorem provide a mathematical foundation for Gibson's notion of persistence perception. Gibson's ecological theory of perception accounts for our knowledge of world objects by borrowing a concept of invariance in topology. A series of transformations can be gradually applied to a pattern, in particular to the shape of an object, without affecting its invariant properties, such as boundedness of parts of a visual scene. High-level representations of objects in our environment are mapped to simplified views (our interpretations) of the objects, in order to construct a symbolic representation of the environment. The representations can be projected continuously to an ecological object that we have seen and continue to see, thanks to the mapping from shapes in our memory to shapes in Euclidean space.
Self-destructive altruism in a synthetic developmental program enables complex feedstock utilization
Authors: Egbert Robert , Brettner Leandra , Zong David , Klavins Eric
Published: November 2016

Cooperation through division of labor underpins biological complexity for organisms and communities. In microbes, stochastic differentiation coupled to programmed cell death drives diverse altruistic behaviors that promote cooperation. Utilizing cell death for developmental multicellular programs requires control over differentiation rate to balance cell proliferation against the utility of sacrifice. However, these behaviors are often controlled by complex regulatory networks and have yet to be demonstrated from first principles. Here we engineered a synthetic developmental gene network that couples stochastic differentiation with programmed cell death to implement a two-member division of labor. Progenitor consumer cells were engineered to grow on cellobiose and differentiate at a controlled rate into self-destructive altruists that release an otherwise sequestered cellulase payload through autolysis. This circuit produces a developmentalEscherichia coliconsortium that utilizes cellulose for growth. We used an experimentally parameterized model of task switching, payload delivery and nutrient release to set key parameters to achieve overall population growth, liberating 14-23% of the available carbon. An inevitable consequence of engineering self-destructive altruism is the emergence of cheaters that undermine cooperation. We observed cheater phenotypes for consumers and altruists, identified mutational hotspots and developed a predictive model of circuit longeivity. This work introduces the altruistic developmental program as a tool for synthetic biology, demonstrates the utility of population dynamics models to engineer multicellular behaviors and provides a testbed for probing the evolutionary biology of self-destructive altruism.
Copyright and the Use of Images as Biodiversity Data
Authors: Egloff Willi , Agosti Donat , Kishor Puneet , Patterson David , Miller Jeremy A.
Published: November 2016

1.

Taxonomy is the discipline responsible for charting the world’s organismic diversity, understanding ancestor/descendant relationships, and organizing all species according to a unified taxonomic classification system. Taxonomists document the attributes (characters) of organisms, with emphasis on those can be used to distinguish species from each other. Character information is compiled in the scientific literature as text, tables, and images. The information is presented according to conventions that vary among taxonomic domains; such conventions facilitate comparison among similar species, even when descriptions are published by different authors.

There is considerable uncertainty within the taxonomic community as to how to re-use images that were included in taxonomic publications, especially in regard to whether copyright applies. This article deals with the principles and application of copyright law, database protection, and protection against unfair competition, as applied to images. We conclude that copyright does not apply to most images in taxonomic literature because they are presented in a standardized way and lack the creativity that is required to qualify as 'copyrightable works'. There are exceptions, such as wildlife photographs, drawings and artwork produced in a distinctive individual form and intended for other than comparative purposes (such as visual art). Further exceptions may apply to collections of images that qualify as a database in the sense of European database protection law. In a few European countries, there is legal protection for photographs that do not qualify as works in the usual sense of copyright. It follows that most images found in taxonomic literature can be re-used for research or many other purposes without seeking permission, regardless of any copyright declaration. In observance of ethical and scholarly standards, re-users are expected to cite the author and original source of any image that they use.
Giardiaalters commensal microbial diversity throughout the murine gut
Authors: Barash NR , Maloney JG , Singer SM , Dawson SC
Published: November 2016

Giardia lambliais the most frequently identified protozoan cause of intestinal infection. Over one billion people are estimated to have acute or chronic giardiasis, with infection rates approaching 90% in endemic areas. Despite its significance in global health, the mechanisms of pathogenesis associated with giardiasis remain unclear as the parasite neither produces a known toxin nor induces a robust inflammatory response.Giardiacolonization and proliferation in the small intestine of the host may, however, disrupt the ecological homeostasis of gastrointestinal commensal microbes and contribute to diarrheal disease associated with giardiasis. To evaluate the impact ofGiardiainfection on the host microbiota, we use culture-independent methods to quantify shifts in the diversity of commensal microbes throughout the entire gastrointestinal tract in mice infected withGiardia. We discovered thatGiardia’scolonization of the small intestine causes a systemic dysbiosis of aerobic and anaerobic bacterial taxa. Specifically, giardiasis is typified by both expansions in aerobicProteobacteriaand decreases in anaerobicFirmicutesandMelainabacteriain the murine foregut and hindgut. Based on these shifts, we created a quantitative index of murineGiardia-induced microbial dysbiosis. This index increased at all gut regions during the duration of infection, including both the proximal small intestine and the colon. Thus giardiasis could be an ecological disease, and the observed dysbiosis may be mediated directly via the parasite’s unique anaerobic fermentative metabolism or indirectly via parasite induction of gut inflammation. This systemic alteration of murine gut commensal diversity may be the cause or the consequence of inflammatory and metabolic changes throughout the gut. Shifts in the commensal microbiota may explain observed variation in giardiasis between hosts with respect to host pathology, degree of parasite colonization, infection initiation, and eventual clearance.