bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling and Simulation of Excitation System for Third Harmonic Brushless Synchronous Generator
Authors: Liu Wei , Zhu Changqing
Published: August 2019

The excitation system of third harmonic excitation brushless synchronous generator (HESG) can improve the voltage stability and is widely used in small and medium generator set. In order to establish the model of harmonic brushless excitation system, the formula of third harmonic EMF is derived. Then, based on the traditional synchronous generator model, the influence of harmonic windings is counted in. Finally, the simulation model of closed-loop excitation system is analyzed with the automatic voltage regulator (AVR) as the core. On the basis of theoretical analysis, simulation and comparative analysis are carried out according to parameters from actual system. The results show that compared with normal synchronous generator, HESG has the advantage of excellent dynamic characteristics and automatic voltage adjustment.
A Rapid Capture Method of Frequency Hopping Communication System in Airborne Data-Link
Authors: Hou Xiaochen , Guo Dechun , Chen Hao , Zhang Zhibo
Published: August 2019

In frequency hopping communication systems, synchronization of frequency hopping sequences is a prerequisite for ensuring normal communication. In this paper, a rapid frequency hopping synchronization capture method is designed based on MSK modulation. A method of solving the constant false alarm threshold is given, and a set of high performance synchronization codes are selected. We assessed the effectiveness of the proposed process by simulation based on MATLAB and Vivado, and it can complete rapid synchronous capture in the frequency hopping communication system.
Authentication algorithm of secure digital halftone watermark based on SM4 algorithm
Authors: Guo L , Wang A L , Li S K , Pang J P , Xin K , Fan S X , Liu F P
Published: August 2019

With the development of information technology, the problem of piracy is getting worse. In order to increase the security of watermark information, this paper has proposed a security watermark authentication algorithm based on SM4 encryption algorithms, which is embedded in the frame of the vehicle image when the watermark information is encrypted. SM4 is the block cipher standard adopted in WAPI of wlan standard in China, and then adopted by commercial cipher standard in China. It is characterized by adding nonlinear changes in the calculation process, which greatly improves the security of the algorithm. Because the watermark information is embedded in the feature points of the structure, which is relatively stable and not easy to change, so the robustness of the watermark is enhanced to a certain extent. Through the test, the algorithm can encrypt and authenticate the watermark information.
DGA and Weibull Distribution Model-based Transformer Fault Early Warning
Authors: Yang Pei , Pan Sen , Jiang Jing , Rao Wei , Qiao Junfeng
Published: August 2019

As an important power transmission and transformation equipment, transformer fault has a great impact on the safe and stable operation of smart grid and probably incurs serious consequences. Therefore, how to detect and warn the fault of transformers as early as possible becomes particularly critical. In this paper, a fault early warning method based on DGA and Weibull distribution model is proposed for a large number of transformers in smart grid and the calculation formulas of the attention value and warning value of transformer fault are given. First, the defect rate and fault rate of transformers can be obtained by analysing the transformer maintenance data. Then, the attention value and warning value of transformer fault are calculated with the Weibull distribution model according to the gases volume distribution of oil chromatographic data, which provides an effective method for the transformer fault early warning. The actual case study shows that the proposed method can effectively achieve the transformer fault early warning.
Power dispatching tracking control of wind turbine considering maximum and limited power generation below rated wind speed
Authors: Wang Huipan , Hu Yang
Published: August 2019

Wind turbines should respond to power dispatching of power grid at all times. According to this demand, this paper puts forward a set of feasible power control strategies below rated wind speed. Firstly, the operation state of wind turbine is divided into two working modes: maximum power generation and wind power curtailment generation. Different control strategies are adopted in different working conditions. Under the mode of maximum power generation, the model predictive control (MPC) algorithm is used to give a torque compensation gain. The MPC controller not only improves the utilization efficiency of wind energy, but also reduces the mechanical load. Under the mode of wind curtailment, a hybrid tracking control strategy of giving priority to torque control than pitch regulation is adopted. It reduces the frequency and amplitude of the pitch mechanism greatly. By comparing the simulation results under various wind speeds, it is found that the proposed power control strategy can adapt to different power dispatching scenes, and can respond to power dispatching with greater performance. It is very significant for the improvement of wind power generation system.
Domestication influences morphological and physiological responses to salinity in Brassica oleracea seedlings
Authors: Lema M , Ali Md Y , Retuerto R
Published: August 2019

Brassica oleracea cultivars include important vegetable and forage crops grown worldwide, whereas the wild counterpart occurs naturally on European sea cliffs. Domestication and selection processes have led to phenotypic and genetic divergence between domesticated plants and their wild ancestors that inhabit coastal areas and are exposed to saline conditions. Salinity is one of the most limiting factors for crop production. However, little is known about how salinity affects plants in relation to domestication of B. oleracea. The objective of this study was to determine the influence of domestication status (wild, landrace or cultivar) on the response of different B. oleracea crops to salinity, as measured by seed germination, plant growth, water content and mineral concentration parameters at the seedling stage. For this purpose, two independent pot experiments were conducted with six accessions of B. oleracea, including cabbage (group capitata) and kale (group acephala), in a growth chamber under controlled environmental conditions. In both taxonomic groups, differences in domestication status and salt stress significantly affected all major process such as germination, changes in dry matter, water relations and mineral uptake. In the acephala experiment, the domestication × salinity interaction significantly affected water content parameters and shoot Na+ allocation. At early stages of development, wild plants are more succulent than cultivated plants and have a higher capacity to maintain lower Na+ concentrations in their shoots in response to increasing levels of salinity. Different responses of domesticated and cultivated accessions in relation to these traits indicated a high level of natural variation in wild B. oleracea. Exclusion of Na+ from shoots and increasing succulence may enhance salt tolerance in B. oleracea exposed to extreme salinity in the long term. The wild germplasm can potentially be used to improve the salt tolerance of crops by the identification of useful genes and incorporation of these into salinity-sensitive cultivars.
Regulatory effect of phosphorus and nitrogen on nodulation and plant performance of leguminous shrubs
Authors: Míguez-Montero M A , Valentine A , Pérez-Fernández M A
Published: August 2019

The impact of phosphorus (P) nutrition on plant growth, symbiotic N2 fixation, and phosphorus and nitrogen use and their assimilation was investigated in four leguminous plants of the genus Cytisus. Plants inoculated with Rhizobium strains isolated from plants of the four species growing in the wild were crop under controlled conditions in soils with either low P (5 µM) or high P (500 µM). The experiment was replicated in the presence and absence of plant irrigation to test for the effects of drought stress of inoculated and non-inoculated plants under the two P levels of fertilization. P-low treatments increased nodule production while plant biomass and shoot and root P and N contents were maximum at sufficient P. The reduction of P in the soil clearly induced biological nitrogen fixation and greater phosphorus and nitrogen uptake efficiencies, as shown by the total N and P accumulated in plants. Similarly, distinct tolerances to drought support this idea. Cytisus balansae had the lowest tolerance to water scarcity. Cytisus multiflorus and Cytisus scoparius were the most resistant species to drought, with this resistance enhanced in the inoculated plants. In the four species, the inoculation treatment clearly enhanced N-use efficiency, whereas P-use efficiency was greater in the non-inoculated plants in the irrigated treatment. With a P-induced demand for N, the plants nodulated prolifically and increased N supply from biological fixation. The physiological basis for N2-fixing C. scoparius and C. striatus maintaining growth at low P supply and responding to greater P supply is through balanced acquisition of P and N for plant demand.

Native shrubby legumes are key species in natural ecosystems due to their capability to increase the net N budget in plants and soils and because they modulate the phosphorus availability. Four legumes in the genus Cytisus either native to or commonly represented in the Iberian Peninsula proved to be able shift their N use depending on the soil P availability and on the interactions established with their Bradyrhizobium symbionts. In the four species the inoculation treatment clearly enhanced N-use efficiency and drought tolerance, whereas P-use efficiency was greater in the non-inoculated plants in the irrigated treatment.
Development and Validation of a Novel, Rapid Gradient HPLC Method for Simultaneous Estimation of Bioactive Marker Compounds in a Mixture of Convolvulus pluricaulis, Withania somnifera and Bacopa monnieri Extracts
Authors: Choudhary Sunayna , Kaur Indu Pal , Malik Jai
Published: August 2019

The use of herbs as medicine is an ancient form of healthcare known to mankind. Standardization of herbal medicines is however a challenging task and is the major bottleneck in their acceptance as the primary therapeutic option. The aim of this study was to develop and validate a simple, rapid HPLC method for standardizing the mixture of extracts of three Medhya Rasayanas (neurotonic), Convolvulus pluricaulis, Withania somnifera and Bacopa monnieri. Simultaneous estimation of the respective bioactive markers of these plants viz., scopoletin, withaferin A, bacoside A 3, bacopaside II, jujubogenin and bacosaponin C has been reported for the first time. The method was developed using Waters Hybrid X-Bridge shield with BEH technology 2.5 μm, 4.6 × 75 mm column and validated according to ICH guidelines. The 20 minutes run time makes the method eco-friendly. The method was linear over a range of 12.5–400 ng/10 μL for scopoletin and 62.5–2,000 ng/10 μL for withaferin A, bacoside A 3, bacopaside II, jujubogenin and bacosaponin C with detection limits of 8.0, 48.3, 30.4, 40.7, 15.6 and 18.9 ng/10 μL and quantification limits of 24.5, 146.5, 92.2, 123.4, 47.4 and 57.4 ng/10 μL, respectively. The correlation coefficient for each analyte was >0.999. The intra-day and inter-day precision was <2%. These results confirmed the precision, accuracy and robustness of the proposed method.
Improved nephrology referral of chronic kidney disease patients: potential role of smartphone apps
Authors: Oliva-Damaso Nestor , Oliva-Damaso Elena , Rodriguez-Perez Jose C , Payan Juan
Published: August 2019

In chronic kidney disease (CKD), referral to nephrology is based on Kidney Disease: Improving Global Outcomes 2012 guidelines and is generally indicated when the estimated glomerular filtration rate (eGFR) is <30 mL/min/1.73 m2 or when there is a rapid decline of eGFR, elevated urinary albumin:creatinine ratio (>300 mg/g) or other ‘alert’ signs such as the presence of urinary red blood cell casts. Since eGFR declines with ageing in otherwise healthy individuals, we propose that the eGFR threshold for nephrology referral should be adjusted according to age. According to current recommendations, young patients without rapidly progressing CKD are referred more often to nephrology when CKD is more severe, compared with age-matched controls with normal eGFRs, than elderly CKD patients. In this commentary, we discuss the age factor and other specific situations not considered in current guidelines for nephrology referral of CKD patients.
Assessing the accuracy of ICD-10 coding for measuring rates of and mortality from acute kidney injury and the impact of electronic alerts: an observational cohort study
Authors: Logan Rachael , Davey Peter , De Souza Nicosha , Baird David , Guthrie Bruce , Bell Samira
Published: August 2019

Background

The application of a uniform definition for acute kidney injury (AKI) is vital to advance understanding and management of AKI. International Classification of Diseases (Tenth Revision) (ICD-10) coding is frequently used to define AKI, but its accuracy is unclear. The aim of this study was to determine whether ICD-10 coding is a reliable method of monitoring rates and outcomes of AKI in inpatients compared with biochemically defined AKI, and whether electronic alerts (e-alerts) for AKI affect ICD-10 AKI coding.

Methods

An observational cohort study of all 505 662 adult admissions to acute hospitals in two Scottish Health Boards [National Health Service (NHS) Tayside and NHS Fife] from January 2013 to April 2017 was performed. AKI e-alerts were implemented in NHS Tayside in April 2015. Sensitivity, specificity, positive and negative predictive values of ICD-10 coding for AKI compared with biochemically defined AKI using the Kidney Disease: Improving Global Outcomes definition and relative risk of 30-day mortality in people with ICD-10 and biochemically defined AKI before and after AKI e-alert implementation were performed.

Results

Sensitivity of ICD-10 coding for identifying biochemically defined AKI was very poor in both health boards for all AKI (Tayside 25.7% and Fife 35.8%) and for Stages 2 and 3 AKI (Tayside 43.8% and Fife 53.8%). Positive predictive value was poor both for all AKI (Tayside 76.1% and Fife 45.5%) and for Stages 2 and 3 AKI (Tayside 45.5% and Fife 36.8%). Measured mortality fell following implementation of AKI e-alerts in the ICD-10-coded population but not in the biochemically defined AKI population, reflecting an increase in the proportion of Stage 1 AKI in ICD-10-coded AKI. There was no evidence that the introduction of AKI e-alerts in Tayside improved ICD-10 coding of AKI.

Conclusion

ICD-10 coding should not be used for monitoring of rates and outcomes of AKI for either research or improvement programmes.
Two decades of the Eurotransplant Senior Program: the gender gap in mortality impacts patient survival after kidney transplantation
Authors: Schachtner Thomas , Otto Natalie M , Reinke Petra
Published: August 2019

Background

Long-term outcomes of the Eurotransplant Senior Program (ESP) are urgently needed to improve selection criteria and allocation policies in the elderly.

Methods

We analysed patient and allograft outcomes of 244 ESP-kidney transplant recipients (KTRs) between 1999 and 2019 and assessed quality of living compared with 82 ESP-waitlisted dialysis patients using standardized short form-8.

Results

We observed 1-, 5- and 10-year patient survival of 91.7, 66.3 and 38.0%, respectively. Mortality risk factors included male gender (P = 0.006) and T-cell-mediated rejection (P < 0.001). Median patient survival of male ESP-KTRs was 80 versus 131 months for female ESP-KTRs (P = 0.006). 1-, 5- and 10-year death-censored allograft survival was 93.3, 82.6 and 70.4%. Risk factors included high body mass index (P < 0.001) and T-cell-mediated rejection (P < 0.001). After re-initiation of dialysis median patient survival was 58 months. Change of estimated glomerular filtration rate showed a mean decline of 2.3 and 6.8 mL/min at 5 and 10 years. Median physical and mental component scores of ESP-KTRs were 40.2 and 48.3, significantly higher compared with dialysis patients (P < 0.05). Of ESP-KTRs, 97.5% who underwent transplantation would again do so.

Conclusions

Long-term outcomes of ESP-KTRs ultimately support the effectiveness of an age-matched allocation system. Our data suggest that the survival advantage of women is maintained after kidney transplantation and calls for gender-specific care.
Multilayered Tuning of Dosage Compensation and Z-Chromosome Masculinization in the Wood White (Leptidea sinapis) Butterfly
Authors: Höök Lars , Leal Luis , Talla Venkat , Backström Niclas
Published: August 2019

In species with genetic sex determination, dosage compensation can evolve to equal expression levels of sex-linked and autosomal genes. Current knowledge about dosage compensation has mainly been derived from male-heterogametic (XX/XY) model organisms, whereas less is understood about the process in female-heterogametic systems (ZZ/ZW). In moths and butterflies, downregulation of Z-linked expression in males (ZZ) to match the expression level in females (ZW) is often observed. However, little is known about the underlying regulatory mechanisms, or if dosage compensation patterns vary across ontogenetic stages. In this study, we assessed dynamics of Z-linked and autosomal expression levels across developmental stages in the wood white (Leptidea sinapis). We found that although expression of Z-linked genes in general was reduced compared with autosomal genes, dosage compensation was actually complete for some categories of genes, in particular sex-biased genes, but equalization in females was constrained to a narrower gene set. We also observed a noticeable convergence in Z-linked expression between males and females after correcting for sex-biased genes. Sex-biased expression increased successively across developmental stages, and male-biased genes were enriched on the Z-chromosome. Finally, all five core genes associated with the ribonucleoprotein dosage compensation complex male-specific lethal were detected in adult females, in correspondence with a reduction in the expression difference between autosomes and the single Z-chromosome. We show that tuning of gene dosage is multilayered in Lepidoptera and argue that expression balance across chromosomal classes may predominantly be driven by enrichment of male-biased genes on the Z-chromosome and cooption of available dosage regulators.
Unique DNA Methylation Profiles Are Associated with cis-Variation in Honey Bees
Authors: Yagound Boris , Smith Nicholas M A , Buchmann Gabriele , Oldroyd Benjamin P , Remnant Emily J
Published: August 2019

DNA methylation is an important epigenetic modification that mediates diverse processes such as cellular differentiation, phenotypic plasticity, and genomic imprinting. Mounting evidence suggests that local DNA sequence variation can be associated with particular DNA methylation states, indicating that the interplay between genetic and epigenetic factors may contribute synergistically to the phenotypic complexity of organisms. Social insects such as ants, bees, and wasps have extensive phenotypic plasticity manifested in their different castes, and this plasticity has been associated with variation in DNA methylation. Yet, the influence of genetic variation on DNA methylation state remains mostly unknown. Here we examine the importance of sequence-specific methylation at the genome-wide level, using whole-genome bisulfite sequencing of the semen of individual honey bee males. We find that individual males harbor unique DNA methylation patterns in their semen, and that genes that are more variable at the epigenetic level are also more likely to be variable at the genetic level. DNA sequence variation can affect DNA methylation by modifying CG sites directly, but can also be associated with local variation in cis that is not CG-site specific. We show that covariation in sequence polymorphism and DNA methylation state contributes to the individual-specificity of epigenetic marks in social insects, which likely promotes their retention across generations, and their capacity to influence evolutionary adaptation.
Bicuspid aortic valve patients show specific epigenetic tissue signature increasing extracellular matrix destruction
Authors: Haunschild Josephina , Schellinger Isabel N , Barnard Sarah J , von Aspern Konstantin , Davierwala Piroze , Misfeld Martin , Petroff David , Borger Michael A , Etz Christian D
Published: August 2019

OBJECTIVES

Patients with a bicuspid aortic valve (BAV) have an increased risk for developing thoracic aortic aneurysm, which is characterized by the destruction of the elastic media of the aortic wall. Several important enzymes have been characterized to play key roles in extracellular matrix homeostasis, namely matrix metalloproteinases (MMPs). In this study, we investigated MMP-2 levels and their epigenetic regulation via the miR-29 family.

METHODS

Aortic tissue samples from 58 patients were collected during cardiac surgery, of which 30 presented with a BAV and 28 with a tricuspid aortic valve. Polymerase chain reaction, western blot analysis and immunohistochemistry were performed to analyse MMP-2. In addition, enzyme-linked immunosorbent assay measurements were carried out to investigate both MMP-2 and tissue inhibitor of metalloproteinase-2 levels. To examine the epigenetic regulation of aortic extracellular matrix homeostasis, we furthermore studied the expression levels of miR-29 via qRT-PCR.

RESULTS

Patients with a BAV were significantly younger at the time of surgery, presented significantly less frequently with arterial hypertension and displayed more often with an additional valvular disease. On a molecular level, we found that MMP-2 is increased on gene and protein level in BAV patients. Tissue inhibitor of metalloproteinase-2 levels do not differ between the groups. Interestingly, we also found that only miR-29A is significantly downregulated in BAVs.

CONCLUSIONS

Our findings highlight the importance of MMP-2 in the context of extracellular matrix destruction in BAV patients. We present new evidence that miR-29A is a crucial epigenetic regulator of these pathomechanistic processes and might hold promise for future translational research.
Destroying Trust in Government: Effects of a Broken Pact among Colombian Ex-Combatants
Authors: Kreutz Joakim , Nussio Enzo
Published: August 2019

Mistrust between conflict parties after civil war is a major hurdle to sustainable peace. However, existing research focuses on elite interactions and has not examined the trust relationship between government and rank-and-file members of armed groups, despite their importance for postconflict stability. We use the unexpected decision of the Colombian government to extradite top-level former paramilitary leaders to the United States in 2008 to identify how a peace deal reversal influences ex-combatants’ trust in government. In theory, they may lose trust for instrumental reasons, if they suffer personal costs, or for normative reasons, if they think the government is failing its commitments. Using quasi-experimental survey evidence, we find that extradition decreases trust substantially among ex-paramilitaries, but not in a comparison group of ex-guerrillas not part of the same peace deal. Even though paramilitaries are seen as particularly opportunistic, our evidence suggests that normative rather than instrumentalist considerations led to trust erosion.
Legal Gender Beyond the Binary
Authors: Gössl Susanne Lilian , Völzmann Berit
Published: August 2019

The article explores the fundamental rights regarding a person’s status registration as neither male nor female and, thus, gender registrations ‘beyond the binary’. The authors analyse the fundamental rights of the individual as codified in the European Convention on Human Rights (ECHR) and examine ‘third options’ in jurisdictions and recent court decisions in Europe. They analyse to what extent similar results might be achieved at the European Court of Human Rights (ECtHR).
A tubo-ovarian abscess mimicking an appendiceal abscess: a rare presentation of Streptococcus agalactiae
Authors: Taylor Gregory M , Erlich Andrew H , Wallace Laurie C , Williams Vernon , Ali Reehan M , Zygowiec Jonathan P
Published: August 2019

A tubo-ovarian abscess (TOA) is a relatively rare medical complication that results from an untreated/unrecognized ascending pelvic infection of the female genital tract. In a right-sided TOA, this clinical entity may mimic appendicitis on computed tomography (CT). In addition, both disease processes can present with pelvic pain, leukocytosis and fever. We present the case of a 47-year-old female with mid right-sided abdominal pain that was diagnosed on CT scan with an appendiceal abscess. She underwent CT-guided percutaneous drainage with interventional radiology. On Day 8, a CT limited study involving a contrast injection was performed to evaluate for abscess resolution. The contrast within the drain filled the fallopian tube, endometrial cavity and contralateral fallopian tube. These findings demonstrated that the initial diagnosis actually represented a TOA. To the authors’ knowledge, this is the only reported case involving a TOA secondary to Streptococcus agalactiae (GBS) mimicking an appendicitis with abscess formation.
A case of protein-losing gastroenteropathy caused by systemic AA amyloidosis secondary to undifferentiated carcinoma of unknown primary origin
Authors: Shiroshita Akihiro , Uegami Wataru , Otsuki Ayumu , Nakashima Kei , Sunagawa Keishin , Fukuoka Junya , Kami Shota , Saito Ayumi , Aoshima Masahiro
Published: August 2019

We report the case of a 61-year-old woman with Kartagener syndrome who presented with a 3-month history of chronic watery diarrhoea and severe hypoalbuminaemia. Histopathological examination of duodenum and large intestine biopsies showed amyloid A (AA) amyloid deposition. Scintigraphy and alpha-1 anti-trypsin clearance evaluations revealed protein-losing gastroenteropathy. Computed tomography with contrast and positron emission tomography showed a pelvic mass with multiple para-aortic lymph node enlargement. We suspected protein-losing gastroenteropathy secondary to AA amyloid produced related to malignant tumours. Following tumour resection, histopathological examination of the lesion revealed undifferentiated carcinoma of unknown origin. Postoperatively, the patient’s nutritional condition improved. There has been no recurrence of protein-losing gastroenteropathy 6 months postoperatively. This is the first report of protein-losing gastroenteropathy and AA amyloidosis secondary to undifferentiated carcinoma. Early recognition and intervention could increase the likelihood of amyloidosis remission.
Predicting Overwintering of Wheat Stripe Rust in Central and Northwestern China
Authors: Hu Xiaoping , Cao Shiqin , Cornelius Alex , Xu Xiangming
Published: August 2019

Stripe rust, caused by Puccinia striiformis Westend. f. sp. tritici Erikss. (Pst), is an important disease of wheat. In China, Pst management has focused on the Gansu region where the pathogen can complete its annual cycle, including oversummering and overwintering. From this region, Pst inoculum is dispersed to the southern Yangtze River region in the late autumn/early winter and then to the main wheat production regions in the following spring. We used historical weather data (1995 to 2016) and field stripe rust assessment data (8 years) in the spring to evaluate the performance of a published model for predicting the potential of Pst overwintering in the Gansu region. Both predicted and observed values of rust overwintering in the Gansu region varied greatly between years and between sites within a single year, indicating the value of predicting rust overwintering for disease management. The model predictions fitted with observed values satisfactorily. All high incidences of rust in the spring were observed in the fields of the monitoring sites where the high potential of overwintering was predicted. Conversely, the predicted rust overwintering potential was also close to zero in the fields where rust was not observed in the spring. There were many false-positive predictions, which may be attributable to the absence of rust in autumn seedlings. This model can be used to target rust management in the spring and its effectiveness will be further improved if autumn rust assessment can be carried out.
Do Patients Require Emergency Department Interventions After Prehospital Naloxone?
Authors: Fidacaro G. Anthony , Patel Prarthi , Carroll Gerard , Bartimus Holly , Hunter Krystal , Hong Rick
Published: August 2019

Objective:

Patients receiving naloxone for suspected opioid overdose in the prehospital setting are typically transported to the emergency department (ED) for further evaluation, regardless of Glasgow Coma Scale (GCS). The objective of our study is to determine whether patients with GCS ≥14 after receiving prehospital naloxone received additional doses of naloxone and medical interventions in the ED compared with those with GCS <14 after prehospital naloxone.

Methods:

Our retrospective observational study included patients ≥18 years old treated with naloxone and transported by an inner-city hospital-based Emergency Medical Services (EMS) to its affiliated ED from January 2, 2016 to December 31, 2016. Investigators collected demographic data, prehospital interventions, GCS, ED interventions, and dispositions. Institutional Review Board approval was obtained. The main outcome measures were repeat doses of naloxone and ED interventions.

Results:

In all, 473 patient encounters were reviewed. Most common route of prehospital naloxone administration was intranasal (68%). Nearly two-thirds (n = 473) of patients had GCS ≥14 upon ED arrival. Repeat naloxone was administered to 3.5% (n = 314) of patients with GCS ≥14 versus 14.6% (n = 159) of patients with GCS <14. ED interventions, such as airway maneuvers, laboratory and radiology testing, and cardiac monitoring, were less common among patients who had improved GCS of 14 or higher (n = 314). There were 8 deaths among patients with GCS <14 (n = 159) and no deaths among patients with GCS ≥14 (n = 314).

Conclusion:

Patients with GCS score ≥14 after administration of prehospital naloxone are less likely to receive additional naloxone doses and medical interventions in the ED compared with those with a GCS score <14 after prehospital naloxone and may present an invaluable opportunity for the ED to initiate an addiction treatment program for patients with nonfatal overdose.
Perceived Behavioral Control and Barriers to Cleaning Skin Before Injecting Drugs
Authors: Kenney Shannon R. , Phillips Kristina T. , Herman Debra S. , Keosaian Julia , Anderson Bradley J. , Stein Michael D.
Published: August 2019

Objectives:

Skin and soft-tissue infections (SSTI) among people who inject drugs (PWID) are common and represent a significant public health burden. In the current study, we examined the relationship between perceived behavioral control and perceived barriers to cleaning skin before injecting drugs.

Methods:

Participants (n = 248; 37.9 [±10.7] years of age, 58.5% male, 59.3% white, 16.1% Hispanic) were patients seeking medical care at a large urban hospital in the northeastern United States. We used ordinary least squares regression to estimate the associations between perceived barriers to skin cleaning with background characteristics and perceived behavioral control.

Results:

Controlling for background and other study variables, greater number of past-year skin abscesses was associated with greater level of perceived barriers to skin cleaning (P < 0.001), whereas higher level of education and higher perceived behavioral control were associated with lower levels of perceived barriers to skin cleaning (P < 0.001).

Conclusions:

Interventions aiming to reduce the likelihood for SSTI among people who inject drugs may benefit from strengthening individual's behavioral control and providing skin cleaning skills training.
Predictive Model for Failed Induction of Labor Among Obese Women
Authors: Rossi Robert M. , Requarth Erin W. , Warshak Carri R. , Dufendach Kevin , Hall Eric S. , DeFranco Emily A.
Published: August 2019

OBJECTIVE:

To evaluate antenatal risk factors associated with failed induction of labor among obese women to develop a predictive model for induction of labor outcome.

METHODS:

We conducted a population-based cohort study of all obese (body mass index higher than 30.0) women with singleton live births who underwent attempted induction of labor between 37 and 44 weeks of gestation in the United States from 2012 to 2016 using de-identified U.S live birth records. The primary objective was to build a predictive model for the probability of induction of labor failure using antenatal factors. Multivariable logistic regression estimated the association of these factors on risk of failed induction of labor. We performed k-fold cross-validation for internal validation and then externally validated the model using a separate live birth cohort from 2017 (n=197,982). An online calculator was developed after validation, and calibration was performed. The 10 variables selected for inclusion in the model in order of significance were prior vaginal delivery, prior cesarean delivery, maternal height, age, weight at delivery, parity, gestational weight gain, Medicaid insurance, pregestational diabetes, and chronic hypertension.

RESULTS:

Among 19,844,580 live births in the United States between 2012 and 2016, 1,098,981 obese women with singleton pregnancies underwent induction of labor, of which 273,184 (24.9%) were unsuccessful. The receiver operator characteristic curve for the 10 variable model achieved an area under the curve (AUC) of 0.79 (95% CI 0.78–0.79). External validation demonstrated a consistent measure of discrimination, with an AUC curve of 0.77 (95% CI 0.76–0.77).

CONCLUSION:

This model provides valuable estimation as to the cumulative effect of multiple factors on the risk of failed induction of labor among obese parturients. The predictive model identifies women at increased or decreased risk (ie, greater than 75% vs less than 20%) for cesarean delivery. This risk calculator may be a useful tool for practitioners in the counseling, triaging, risk stratifying, and delivery planning for obese women before attempted induction of labor.
Serum Uric Acid Measurement in Women With Hypertensive Disorders of Pregnancy
Authors: Chescheir Nancy C.
Published: August 2019

A 27-year-old asymptomatic primigravid woman at 36 weeks of gestation is evaluated in the labor and delivery unit with new-onset hypertension of 145/92 mm Hg (with similar measurements 4 hours apart). A spot urine protein/creatinine ratio is 0.35, serum transaminases and creatinine level are normal, and uric acid is 6.0 mg/dL (upper limit of normal for adult woman is 6.0 mg/dL but typically 4–5 mg/dL in the third trimester).1 Antenatal fetal testing and growth on ultrasound scan are reassuring. She is discharged for home management and ultimately delivered at 37 weeks of gestation for preeclampsia without severe features.
Association of Labor With Neonatal Respiratory Outcomes at 36–40 Weeks of Gestation
Authors: Plunkett Beth A. , Sandoval Grecio , Bailit Jennifer L. , Reddy Uma M. , Wapner Ronald J. , Varner Michael W. , Thorp John M. , Caritis Steve N. , Prasad Mona , Tita Alan T. N. , Saade George R. , Sorokin Yoram , Rouse Dwight J. , Blackwell Sean C. , Tolosa Jorge E. ,   for the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Maternal-Fetal Medicine Units (MFMU) Network
Published: August 2019

OBJECTIVE:

To evaluate whether labor is associated with lower odds of respiratory morbidity among neonates born from 36 to 40 weeks of gestation and to assess whether this association varies by gestational age and maternal diabetic status.

METHODS:

We conducted a secondary analysis of women in the Assessment of Perinatal Excellence obstetric cohort who delivered across 25 U.S. hospitals over a 3-year period. Women with a singleton liveborn nonanomalous neonate who delivered from 36 to 40 weeks of gestation were included in our analysis. Those who received antenatal corticosteroids, underwent amniocentesis for fetal lung maturity, or did not meet dating criteria were excluded. Our primary outcome was composite neonatal respiratory morbidity, which included respiratory distress syndrome, ventilator support, continuous positive airway pressure, or neonatal death. Maternal characteristics and neonatal outcomes between women who labored and those who did not were compared. Multivariable logistic regression models were used to evaluate the association between labor and the primary outcome. Interactions between labor and diabetes mellitus and labor and gestational age were tested.

RESULTS:

Our analysis included 63,187 women who underwent labor and 10,629 who did not. There was no interaction between labor and diabetes mellitus (P=.90). However, there was a significant interaction between labor and gestational age (P=.01). In the adjusted model, labor was associated with lower odds of neonatal respiratory morbidity compared with no labor for neonates delivered from 36–39 weeks of gestation. A 1-week increase in gestational age was associated with a 1.2 times increase in the adjusted odds ratio for the neonatal outcome comparing labor and no labor.

CONCLUSION:

Labor was associated with lower odds of the composite outcome among neonates delivered from 36–39 weeks of gestation. The magnitude of this association varied by gestational age. The association was similar for women with or without diabetes mellitus.
Developing as an Academic Medical Educator in Obstetrics and Gynecology
Authors: Graziano Scott C. , Page-Ramsey Sarah M. , Buery-Joyner Samantha D. , Bliss Susan , Craig LaTasha B. , Forstein David A. , Hampton Brittany S. , Hopkins Laura , McKenzie Margaret L. , Morgan Helen , Pradhan Archana , Everett Elise N. ,   for the Undergraduate Medical Education Committee, Association of Professors of Gynecology and Obstetrics
Published: August 2019

The lack of a defined framework for advancement and development of professional identity as a medical educator may discourage faculty from pursuing or progressing through a career in academic medical education. Although career advancement has historically been linked to clinical work and research, promotion for teaching has not been supported at the same level. Despite potential challenges, a career in academic medicine has its share of rewards. This article by the Association of Professors of Gynecology and Obstetrics Undergraduate Medical Education Committee will describe how to develop as an academic medical educator in obstetrics and gynecology, providing tips on how to start, advance, and succeed in an academic career, and provide an overview of available resources and opportunities.
Transfer of Candesartan Into Human Breast Milk
Authors: Coberger Elle Dagmar , Jensen Berit Packert , Dalrymple Judith Maree
Published: August 2019

BACKGROUND:

There are currently no data regarding the transfer of candesartan into human milk. This report provides data on this transfer, an estimation of the amount breastfed infants receive, and plasma concentrations from two breastfed infants.

CASES:

Three breastfeeding mothers, all stabilized on candesartan (8–32 mg/d), provided milk and plasma samples over one dosing interval (24 hours). Two infant plasma samples were obtained. The amount the infants ingested was estimated to be 0.09% (95% CI 0.07–0.11) of the maternal dose (weight-adjusted). Candesartan was undetectable (less than 0.2 micrograms/L) in infant plasma samples.

CONCLUSION:

A relative infant dose of 0.09% suggests that maternal benefit from candesartan at standard therapeutic doses may outweigh risk in breastfeeding healthy, term infants.
Spectrum of Current Management of Pediatric Pulmonary Hypertensive Crisis
Authors: Bernier Meghan L. , Romer Lewis H. , Bembea Melania M.
Published: August 2019

Objectives:

Pulmonary hypertension is a growing pediatric problem and children may present with pulmonary hypertensive crisis—a life-threatening emergency requiring acute interventions. The aim of this study was to characterize the broad spectrum of care provided in North American PICUs for children who present with pulmonary hypertensive crisis.

Design:

Electronic cross-sectional survey. Survey questions covered the following: demographics of the respondents, institution, and patient population; pulmonary hypertension diagnostic modalities; pulmonary hypertension-specific pharmacotherapies; supportive therapies, including sedation, ventilation, and inotropic support; and components of multidisciplinary teams.

Setting:

PICUs in the United States and Canada.

Subjects:

Faculty members from surveyed institutions.

Interventions:

None.

Measurement and Main Results:

The response rate was 50% of 99 identified institutions. Of the respondents, 82.2% were pediatric intensivists from large units, and 73.9% had over a decade of experience beyond training. Respondents provided care for a median of 10 patients/yr with acute pulmonary hypertensive crisis. Formal echocardiography protocols existed at 61.1% of institutions with varying components reported. There were no consistent indications for cardiac catheterization during a pulmonary hypertensive crisis admission. All institutions used inhaled nitric oxide, and enteral phosphodiesterase type 5 inhibitor was the most frequently used additional targeted vasodilator therapy. Milrinone and epinephrine were the most frequently used vasoactive infusions. Results showed no preferred approach to mechanical ventilation. Fentanyl and dexmedetomidine were the preferred sedative infusions. A formal pulmonary hypertension consulting team was reported at 51.1% of institutions, and the three most common personnel were pediatric cardiologist, pediatric pulmonologist, and advanced practice nurse.

Conclusions:

The management of critically ill children with acute pulmonary hypertensive crisis is diverse. Findings from this survey may inform formal recommendations - particularly with regard to care team composition and pulmonary vasodilator therapies - as North American guidelines are currently lacking. Additional work is needed to determine best practice, standardization of practice, and resulting impact on outcomes.
Embolic Hypodermic Needle Causing Traumatic Cardiac Tamponade: A Case Report
Authors: Yen Albert F. , Homer Christina M. , Mohapatra Alexander , Langnas Erica , Gomez Antonio , Hendrickson Carolyn M.
Published: August 2019

Objectives:

We present a unique case of a broken fragment of a hypodermic needle breaking and embolizing to the heart. This needle subsequently penetrated the right ventricle and the patient developed hemopericardium which resulted in cardiac tamponade physiology.

Data Sources:

None.

Study Selection:

None.

Data Extraction:

None.

Data Synthesis:

Recognizing the potential for unusual and serious complications of IV illicit drug use is an important part of providing effective and timely medical care in this vulnerable population.

Conclusions:

An embolic needle phenomenon can have significant sequela, including direct cardiac trauma leading to tamponade and subsequent cardiac collapse. Partnering with the patient to take a detailed history was critical in uncovering the underlying etiology of this patient’s cardiogenic shock.
Pilot Study to Assess Safety and Usability of the Kyron NPWT System
Authors: Karki Bishal , Rai Shankar Man , Nakarmi Kiran , Laminchhane Apar , Maharjan Niran , Giri Piyush , Pathak Kamal , Spielman Amanda , Kung Tiffany H. , Ludwig Cassie A.
Published: August 2019

Background:

There is an evident need for Negative Pressure Wound Therapy (NPWT) systems specifically designed for use in resource-constrained settings to aid in the treatment of open wounds.

Methods:

Prospective single-arm interventional pilot study of 14 patients with complex wounds was conducted at Kirtipur Hospital in Kathmandu, Nepal. A novel NPWT device, the Kyron Suction Unit, was used by 4 plastic surgeons. Primary outcomes were ease of use (10-point Likert scale) and device safety (adverse events recorded). Pain (Visual Analogue Scale score), quality of life (modified EuroQol Derived Single Index scores), and wound dimensions were recorded.

Results:

User ratings on the 10-point Likert scale indicated high confidence and ease of use: median confidence setting up the device of 1.0 [interquartile range (IQR), 1.0; mean 2.3], median confidence maintaining the device of 1.0 (IQR, 1.0; mean, 1.5), and median ease of disassembly of 1.0 (IQR, 1.0; mean, 1.4). Significant improvement in Visual Analogue Scale scores (P = 0.03), modified EuroQol Derived Single Index scores (P < 0.001), and a reduction in wound volume [median, 47.25–9.75 cm3 (P = 0.01)]. Image analysis of wounds pretreatment and posttreatment demonstrated increase in granulation tissue surface area [median, 7.6–28.7 cm2 (P = 0.003)] and decrease in open wound surface area [median, 48.33–33.6 cm2 (P = 0.01)].

Conclusions:

The Kyron Suction Unit was safe and easily managed by plastic surgeons. The device design promoted access to NPWT, a therapy proven to reduce healing time and decrease complications for patients with open wounds, in a resource-constrained setting.
Acellular Dermal Matrix Sterility: Does It Affect Microbial and Clinical Outcomes Following Implantation?
Authors: Klein Gabriel M. , Singh Gurtej , Marquez Jocellie , Gebre Matthew , Barry Robert , Huston Tara L. , Ganz Jason C. , Khan Sami U. , Dagum Alexander B. , Bui Duc T.
Published: August 2019

Introduction:

The use of acellular dermal matrices (ADMs) in breast reconstruction is a controversial topic. Recent literature has investigated the effects of ADM sterilization on infectious complications, although with varying conclusions. Previous work by our group showed no difference between aseptic and sterilized products immediately out of the package. In this study, we investigate the microbiologic profiles of these agents after implantation.

Methods:

In this prospective study, we cultured samples of ADM previously implanted during the first stage of tissue expander-based immediate breast reconstruction. A 1 cm2 sample was excised during the stage II expander–implant exchange procedure, and samples were incubated for 48 hours in tryptic soy broth. Samples with growth were further cultured on tryptic soy broth and blood agar plates. Patient records were also analyzed, to determine if ADM sterilization and microbial growth were correlated with infectious complications.

Results:

In total, 51 samples of ADM were collected from 32 patients. Six samples were from aseptic ADM (AlloDerm), 27 samples were from ADM sterilized to 10–3 (AlloDerm Ready-to-Use), and 18 samples were from products sterilized to 10–6 (AlloMax). No samples demonstrated bacterial growth. Only 5 patients experienced postoperative complications, of whom only 1 patient was infectious in nature. We failed to demonstrate a statistically significant correlation between sterility and postoperative complications.

Conclusions:

Our findings showed no difference in microbial presence and clinical outcomes when comparing ADM sterility. Furthermore, no samples demonstrated growth in culture. Our study brings into question the necessity for terminal sterilization in these products.