bluuebunny/crossref_metadata_2025 huggingface dataset:
Study and analysis the effect of variable applied voltage on SCIM performances based on FEA
Authors: Al-Jubori Waleed Khalid Shakir , Ahmed Yasir Abdulhafedh
Published: June 2020

Study and analysis the effect of variable applied voltage on SCIM performances based on FEA is presented. Three phase squirrel cage induction motor SCIM has been investigated and numerically simulated using finite element method (FEM) with the aid of ANSYS software (RMxprt and Maxwell 2D/3D). This research presents study and analysis of the effects of the voltage variation on performance and efficiency of the three-phase induction motor of the squirrel cage type. The Finite Elements Analysis Method FEA is used as one of the best methods for analysis and simulation of electrical motors in addition to the possibility of dealing with nonlinear equations, Since the induction motor is a complex electromagnetic reaction, the researchers used the ANSYS program to represent and analyze the performance of the motor under variable supply voltage. The case studied in this research is three phases, 380V, 50Hz, 2.2kW, induction motor that widely use in industrial application. The aim of this research is to study the effect of voltage variation on efficiency, current value, power factor and torque of SCIM.  The RMxprt software has been used for modeling and simulating the induction motor and calculating the values of phases currents, input and output power in additional of overall efficiency at steady state condition. The next stage of the research is creating Maxwell 2-D design from the base model of RMxprt software, Maxwell 2-D model has the ability to computing the distribution of magnetic field and explaining the performance under steady-state operation. The obtained results show significant reduction of motor performance due to the effect of variation of apply voltage.
Nonlinear control of GTI for stabilizing future smart grids
Authors: Khather Salam Ibrahim
Published: June 2020

The most important components of the distributed generation frameworks is the GTIs which is an interface amidst the utility and the source of energy. The recent years have seen an increased interest in the design and usage of GTIs due to its smaller weight and size, low cost and higher efficiency. But the problem of leakage currents in the transformerless inverter that is dependant on its topology and control scheme needs to be looked into carefully. Also, the high performance of the GTI requires a stringent control and various control systems are being developed and applied to the GTIs. This paper reviews the various topologies that are classified based on the attributes of the leakage current and the method of decoupling. Further it reviews and compares the different control techniques applied to the GTIs with respect to the frame of reference, controller, modulation technique and the control parameters considered.
Full versus decoupled constant matrices to speed up power system state estimation
Authors: Majdoub Meriem , Cheddadi Bouchra , Sabri Omar , Belfqih Abdelaziz , Boukherouaa Jamal
Published: June 2020

This paper presents a performance evaluation of two solutions to reduce computational burden of the traditional Weighted Least Squares Algorithm for power system state estimation: Simplified methods SWLS1 / SWLS2 based on full constant matrices and Fast decoupled FDWLS based on decoupled constant matrices. First, the algorithms were tested on IEEE 14 and 118 bus transmission systems. Second, the solutions were tested on a rural distribution feeder to evaluate the response of the algorithms to high R/X ratio. Results show that for transmission systems, FDWLS is the fastest method but more sensitive to erroneous measurements. Simplifications considered in FDWLS, are not valid in distribution systems with high R/X ratio this results in slowing down the algorithm convergence speed considerably compared to SWLS2 which performs well. SWLS2 algorithm presents a promising solution to reduce computation time for application in future smart grid.
Optimal design of a single-phase APF based on PQ theory
Authors: Soomro Dur Muhammad , Alswed Sager K. , Abdullah Mohd Noor , Radzi Nur Hanis Mohammad , Baloch Mazhar Hussain
Published: June 2020

The instantaneous active and reactive power (PQ) theory is one of the most widely used control theory for shunt active power filter (SAPF), which can be implemented in single-phase and three-phase systems. However, the SAPF with PQ theory still had ability to improve to become more efficient. This paper presents the optimal design of a single-phase SAPF in terms of reducing the current harmonic distortion and power loss in voltage source inverter (VSI) controlled with the semiconductor switching devices IGBT, MOSFET and Hybrid (combination of IGBT and MOSFET). In order to reduce the switching frequency and power loss of VSI, instead of using single-band hysteresis current controller (HCC), double-band HCC (DHCC) and triple-band HCC (THCC) is used in the SAPF. The designed SAPF is tested with different non-linear loads to verify the results by using MATLAB Simulink.
Stability and Change in Grammatical Gender: Pronouns in Heritage Scandinavian
Authors: Johannessen Janne Bondi , Larsson Ida
Published: June 2020

Previous studies on gender in Scandinavian heritage languages in America have looked at noun-phrase internal agreement. It has been shown that some heritage speakers have non-target gender agreement, but this has been interpreted in different ways by different researchers. This paper presents a study of pronominal gender in Heritage Norwegian and Swedish, using existing recordings and a small experiment that elicits pronouns. It is shown that the use of pronominal forms is largely target-like, and that the heritage speakers make gender distinctions. There is, however, some evidence of two competing systems in the data, and there is a shift towards a two-gender system, arguably due to koinéization.
New synonyms in Celastraceae toward an update of the flora of Brazil

Authors: BIRAL LEONARDO
Published: June 2020

This paper proposes nine new synonyms for seven Brazilian taxa from two genera: Monteverdia and Plenckia (Celastroideae). This proposal is a preliminary step in the Celastraceae treatment for the ongoing “Flora do Brasil 2020” project. Most of the names discussed here had been neglected in literature and are absent in available taxonomic revisions, with some being discussed for the first time after the publication. Additionally, lectotypes for seven names are designated here.
A taxonomic review of the Afrotropical genus Dragmatucha Meyrick, 1908 (Lepidoptera, Gelechioidea, Lecithoceridae, Torodorinae), with descriptions of eleven new species
Authors: PARK KYU-TEK , KOO JUN-MO , AGASSIZ DAVID J. L. , AARVIK LEIF
Published: June 2020

The genus Dragmatucha Meyrick is reviewed and 11 species of a total of 13 are described as new. The new species originate from the Democratic Republic of Congo, Ghana, Kenya, and Uganda. Based on morphological characters, especially the color pattern of both wings, the genus is divided into two species-groups: the proaula species-group with five species (D. proaula Meyrick, 1908; D. galbinea Park, sp. nov.; D. kabarolensis Park, sp. nov.; D. saltualis Park, sp. nov. and D. vittatella Park, sp. nov.) and the hispidula species-group with eight species (D. hispidula Park, 2018; D. goniotes Park, sp. nov.; D. cochliana Park, sp. nov.; D. pedalis Park, sp. nov.; D. ghanaensis Park, sp. nov.; D. crinifrutalis Park, sp. nov.; D. dizostera Park, sp. nov. and D. kakumensis Park, sp. nov.). Adults and male genitalia of all new species are illustrated, but female genitalia are provided only for D. ghanaensis Park, sp. nov. and D. kakumensis Park, sp. nov. When fresh material was available, the analysis of COI sequences was undertaken.
On two species of the spider genus Stertinius Simon, 1890 from China (Araneae: Salticidae)
Authors: WANG CHENG , MI XIAO-QI , IRFAN MUHAMMAD , PENG XIAN-JIN
Published: June 2020

Stertinius Simon, 1890 belongs in the subtribe Simaethina Simon, 1903 of the subfamily Salticinae Blackwall, 1841 (Maddison 2015), which represents a group of small spiders with flatted prosoma and conspicuous, sclerotized sigillae (Logunov et al. 1997; Logunov 2018). Currently, a total of 12 species have been described mainly from East and Southeast Asia, of which five species have only one sex described (World Spider Catalog 2020).
Contribution to the knowledge of the caddisfly fauna of Algeria: An updated checklist of Algerian Trichoptera with new records from the Aures region
Authors: DAMBRI BESMA M. , KARAOUZAS IOANNIS , SAMRAOUI BOUDJÉMA , SAMRAOUI FARRAH
Published: June 2020

The caddisfly fauna of Algeria is poorly known and the few sporadic studies available were carried out decades ago. In this study, caddisfly larvae, pupae, and adults were collected in 11 stream localities from the Aures region, northeastern Algeria. Caddisflies were regularly sampled between April 2018 and February 2020. Two genera are new records to Algeria: Plectrocnemia and Setodes. In addition, four Trichoptera species are new to the Algerian fauna: Tinodes dives, Hydropsyche modesta, Plectrocnemia conspersa and Setodes acutus. Future caddisfly surveys in the region will doubtlessly contribute significantly to the incompletely known Trichoptera fauna of Algeria.
A Novel Functionalization of Bioactive Antimicrobial Peptide onto the Nano-CeO2/Reduced Graphene Oxide Cluster Type Biocomposite Wound Dressings for Diabetic Wound Care Management: In Vitro and In Vivo Evaluations
Authors: Wei Ran , Nie Shijun , Ma Jing , Feng Changmei , Kuang Hongyu
Published: June 2020

Diabetic wound ulcers and unhealed ulcerations have caused in severe difficulties of diabetic patients all around the world. The anti-microbial peptides (AMP) and nanomaterials have been demonstrated beneficial in diabetic wound healing studies. Diabetic wound healing process can be
delayed significantly due to the infection issues. Hence in this report, biologically synthesized cerium oxide (CeO2) nanoparticles incorporated with reduced graphene oxide (RGO) and AMP for effective and rapid diabetic wound healing have been reported. At first, reduced graphene
oxide was prepared from graphene oxide to prepare CeO2/RGO nanocomposites. Biocompatible AMP (IP-1) functionalized CeO2/RGO nanocomposites were accordingly prepared to study the diabetic wound healing process. Rats, the wound healing models with the wound size of about
1.5 cm2 were tested with the as-prepared samples. Further, the prepared samples were tested in a wound healing model of rate with the wound of size 1.5 cm2. Almost complete recovery of wounds i.e., 100% closure of wound area was observed after 2 weeks of treatment by
the prepared samples. Biocompatible AMP (IP-1) functionalized CeO2/RGO nanocomposites enhances rapid keratinocytes proliferation by short time thereby it proves the enhanced ability of the prepared samples to act as a wound healing in-vivo drugs. HE and MTC staining protocols
to illustrate histological observations elucidates the keratinocytes creation by biocompatible AMP (IP-1) functionalized CeO2/RGO nanocomposites.
Intraseasonal Variability of Cross-Slope Flow in the Northern South China Sea
Authors: Wang Qiang , Zhou Weidong , Zeng Lili , Chen Ju , He Yunkai , Wang Dongxiao
Published: June 2020

Cross-slope flow plays an important role in the exchange of material, heat, and momentum between the continental shelf and the open sea. In the northern South China Sea (SCS), long-period observations confirm that there is significant cross-slope flow. The variability of this flow is dominated by the intraseasonal component (i.e., the 10–90-day period band) that contributes 74.6% of the total standard deviation. The 10–90-day bandpassed cross-slope flow exhibits almost the same direction vertically in the observed layers, and its first empirical orthogonal function, whose direction is also not changed, contributes 86.7% to its total variance. The strong 10–90-day bandpassed cross-slope flow is phase locked to the boreal winter half year. The intraseasonal variability of cross-slope flow is mainly associated with mesoscale eddies west to the Luzon Strait. The contrasting baroclinic instability growth rates, strong in winter and weak in summer, result in a seasonal cycle of mesoscale eddy kinetic energy, that is, vigorous in winter and weak in summer, which explains the winter phase lock. The interannual variability of baroclinic instability growth rate is mainly determined by the vertical shear of velocity. The strongest vertical shear of velocity from 2014 to 2016 occurred in the winter of 2016/17 and induced the most rapid baroclinic instability growth rate and consequently the largest mesoscale eddy kinetic energy, which resulted in the strongest intraseasonal variability of cross-slope flow. The vertical shear of velocity in the northern SCS is mainly determined by the Luzon Strait transport.
An Integrated Geometric and Topological Approach for the Identification and Visual Analysis of Rossby Wave Packets
Authors: Pandey Karran , Monteiro Joy Merwin , Natarajan Vijay
Published: June 2020

A new method for identifying Rossby wave packets (RWPs) using 6-hourly data from the ERA-Interim is presented. The method operates entirely in the spatial domain and relies on the geometric and topological properties of the meridional wind field to identify RWPs. The method represents RWPs as nodes and edges of a dual graph instead of the more common envelope representation. This novel representation allows access to both RWP phase and amplitude information. Local maxima and minima of the meridional wind field are collected into groups. Each group, called a υ-max cluster or υ-min cluster of the meridional wind field, represents a potential wave component. Nodes of the dual graph represent a υ-max cluster or υ-min cluster. Alternating υ-max clusters and υ-min clusters are linked by edges of the dual graph, called the RWP association graph. Amplitude and discrete gradient-based filtering applied on the association graph helps identify RWPs of interest. The method is inherently robust against noise and does not require smoothing of the input data. The main parameters that control the performance of the method and their impact on the identified RWPs are discussed. All filtering and RWP identification operations are performed on the association graph as opposed to directly on the wind field, leading to computational efficiency. Advantages and limitations of the method are discussed and are compared against (transform-based) envelope methods in a series of experiments.
Applicant-to-Residency Program Communication: Does It Matter?
Authors: Solis Roberto N. , Quesada Pompeyo R. , Ma Cheng , Olinde Lindsay M. , Diaz Rodney C.
Published: June 2020

Objectives:

To elucidate the frequency and types of pre- and post-interview communication that applicants engage with programs, to garner the perceptions of both applicants and program directors (PDs), and determine if communication influences outcomes.

Subjects and Methods:

Electronic surveys were distributed to otolaryngology residency applicants, and to PDs of ACGME-accredited otolaryngology programs after the 2018 to 2019 application cycle.

Results:

93 of 324 applicants (28.7%) and 33 of 106 PDs (31.3%) responded. In the pre-interview period, 58.1% of applicants sent emails of interest, and 41.9% had a mentor initiate communication. In the post-interview period, the majority of applicants (82.8%) sent notes of intent to their number one choice, and 32.3% had a faculty mentor communicate this on their behalf. The majority of PDs (84.8%) were undecided or did not believe that emails of interest influence decisions to offer an interview, whereas 81.8% believed that communication initiated by an applicant’s mentor has an impact on interview offers. No PD agreed that declarations of intent from applicants have an impact on their rank lists, while only 33.3% of PDs believed that a mentor communicating this for an applicant has some impact. Our statistical findings are in agreement with these perceptions as neither applicant-initiated pre-interview ( P = .54), mentor-initiated pre-interview ( P = .62), applicant-initiated post-interview ( P = .11) nor mentor-initiated post-interview ( P = .78) communications influenced the number of interviews received or ultimate match outcome.

Conclusion:

Pre- and post-interview communication practices vary widely among otolaryngology applicants. Applicant-initiated communication has no impact on outcomes, while mentor-initiated communication is perceived to have more benefit, despite not impacting interview or match outcomes in this study.
Functional vitamin B12 deficiency in phenylketonuria patients and healthy controls: An evaluation with combined indicator of vitamin B12 status as a biochemical index
Authors: Akış Merve , Kant Melis , Işık İshak , Kısa Pelin Teke , Köse Engin , Arslan Nur , İşlekel Hüray
Published: June 2020

Background

Vitamin B12 deficiency frequently appears in phenylketonuria patients having a diet poor in natural protein. The aims of this study were to evaluate vitamin B12 status in phenylketonuria patients by using combined indicator of vitamin B12 status (cB12) as well as methylmalonic acid and homocysteine, more specific and sensitive markers, in comparison with healthy controls.

Methods

Fifty-three children and adolescents with phenylketonuria under dietary treatment and 30 healthy controls were assessed cross-sectionally. Serum vitamin B12 and folate concentrations were analysed by chemiluminescence immunoassay. Plasma methylmalonic acid and total homocysteine concentrations were measured by liquid chromatography-tandem mass spectrometry and liquid chromatography, respectively. cB12 was calculated by using a formula involving blood parameters.

Results

Methylmalonic acid and folate concentrations in phenylketonuria group were higher compared with controls. Methylmalonic acid concentrations were high in 56.5% of the patients and 26.7% of the controls with normal vitamin B12 concentrations. Based on cB12, a significant difference within the normal values was detected between the groups. However, although 24.5% of phenylketonuria patients and 13.3% of controls had decreased vitamin B12 status according to cB12, there was no significant difference.

Conclusion

Children and adolescents with phenylketonuria having a strict diet can be at risk of functional vitamin B12 deficiency. This deficiency can be accurately determined by measuring methylmalonic acid concentrations. Calculation of cB12 as a biochemical index did not provide additional information compared with the measurement of methylmalonic acid alone, but may be helpful for classification of some patients with increased methylmalonic acid as having adequate vitamin B12 status.
Measurement of faecal haemoglobin with a faecal immunochemical test can assist in defining which patients attending primary care with rectal bleeding require urgent referral
Authors: Digby Jayne , Strachan Judith A , McCann Rebecca , Steele Robert JC , Fraser Callum G , Mowat Craig
Published: June 2020

Background

Current guidelines document persistent rectal bleeding as an alarm symptom in patients presenting to primary care. We studied whether a faecal immunochemical test could assist in their assessment.

Methods

From December 2015, faecal immunochemical tests were routinely available to primary care when assessing patients with new-onset bowel symptoms: general practitioners were encouraged to include faecal haemoglobin concentration (f-Hb) within any referral to secondary care. Results with f-Hb ≥10  μg Hb/g faeces were defined as positive. The incidence of significant bowel disease (SBD: colorectal cancer [CRC], higher-risk adenoma [HRA: any ≥1 cm, or three or more] and inflammatory bowel disease [IBD]) at subsequent colonoscopy, referred symptoms and f-Hb were recorded.

Results

Of 1447 patients with a faecal immunochemical test result and colonoscopy outcome, SBD was diagnosed in 296 patients (20.5%; 95 with CRC, 133 with HRA, and 68 with IBD). Four hundred and sixty-two patients (31.9%) reported rectal bleeding: 294 had f-Hb ≥10  μg Hb/g faeces. At colonoscopy, 105/294 had SBD versus 14/168 with rectal bleeding and f-Hb <10  μg Hb/g faeces ( P < 0.0001), comprising one case of CRC (0.6%), 12 HRA (7.1%) and one new case of IBD (0.6%); further, the single cancer and 8 of the 12 HRA were located in the descending colon.

Conclusion

Patients with rectal bleeding and f-Hb <10  μg Hb/g faeces are unlikely to have SBD and could be investigated by sigmoidoscopy alone. Using the faecal immunochemical test to guide investigation of patients with rectal bleeding is a rational and practical way forward.
Book review: Gunnel Cederlöf and Mahesh Rangarajan, eds, At Nature’s Edge: The Global Present and Long-Term History
Authors: Govindrajan Radhika
Published: June 2020

Gunnel Cederlöf and Mahesh Rangarajan, eds, At Nature’s Edge: The Global Present and Long-Term History, Delhi: Oxford University Press, 2018, 331 pp.
The Effectiveness of Family-Supportive Supervisors: The Moderating Role of Employees’ Collectivistic Self-Construal
Authors: Wang Peng , Luo Zhengxue , Wang Zhen
Published: June 2020

Built upon conservation of resource theory and self-determination theory, this study explores boundary conditions under which family-supportive supervisors (FSSs) influence employee-perceived leader–member exchange (LMX) and work–family enrichment (WFE). Findings from this research reveal that FSSs positively relate to employee perceptions of LMX and WFE. Employees’ collectivistic self-construals moderate the effect of FSSs on LMX but not on WFE. Implications and future research directions are discussed.
Diversity and Perceptions of Immigration: How the Past Influences the Present
Authors: McLaren Lauren , Neundorf Anja , Paterson Ian
Published: June 2020

The question of whether high immigration produces anti-immigration hostility has vexed researchers across multiple disciplines for decades. And yet, understanding this relationship is crucial for countries dependant on immigrant labour but concerned about its impact on social cohesion. Absent from most of this research are theories about the impact of early-years socialisation conditions on contemporary attitudes. Using the British sample of the European Social Survey (2002–2017) and two innovative approaches to modelling generational differences – generalised additive models and hierarchical age‒period‒cohort models – this paper shows that rather than producing hostility to immigration, being socialised in a context of high immigrant-origin diversity is likely to result in more positive attitudes to immigration later in life. This implies that through generational replacement, countries like the UK are likely to become increasingly tolerant of immigration over time. Importantly, however, a context of high-income inequality may diminish this effect.
Great Equalizer or Great Selector? Reconsidering Education as a Moderator of Intergenerational Transmissions
Authors: Fiel Jeremy E.
Published: June 2020

A long-standing consensus among sociologists holds that educational attainment has an equalizing effect that increases mobility by moderating other avenues of intergenerational status transmission. This study argues that the evidence supporting this consensus may be distorted by two problems: measurement error in parents’ socioeconomic standing and the educational system’s tendency to progressively select people predisposed for mobility rather than to actually affect mobility. Analyses of family income mobility that address both of these problems in three longitudinal surveys converge on new findings. Intergenerational mobility is significantly lower among high school dropouts than among others, but there are no significant differences in mobility across higher education levels. This is consistent with compensatory advantage processes among the least educated in which individuals from advantaged backgrounds use family-based resources to compensate for their lack of human capital.
Tympanostomy Tube Innovation: Advances in Device Material, Design, and Office-Based Technology
Authors: Whelan Rachel L. , Maguire Raymond C.
Published: June 2020

Objectives:

With tympanostomy tube insertion remaining the most common procedure performed in children to date, growing interests in minimizing both procedural costs and anesthetic exposure in the pediatric population have inspired innovation with respect to tympanostomy tubes. As such, we aim to discuss the current state of tympanostomy tube innovation including insertion devices, tube material, and design.

Methods:

Computerized literature review.

Results:

(1) Numerous single-use devices consisting of a myringotomy knife and preloaded tympanostomy tube offer potential advantages of decreasing or eliminating operating room time and may be performed under moderate instead of a general anesthetic. (2) Innovation with respect to tympanostomy tube material and design may offer enhanced ototopical drug delivery, decreased rates of tube occlusion, and/or the ability to dissolve “on-command” with application of a novel ototopical material. (3) These technologies currently remain in various phases of preclinical and clinical testing.

Conclusions:

While clinical testing for a number of new technologies is preliminary and ongoing, tympanostomy tube-related innovations hold exciting promise to supplement or potentially replace the present-day armamentarium of tympanostomy tube design and insertion moving forward.
Maxillary Sinus Ameloblastoma: Transnasal Endoscopic Management
Authors: Karp John , Xiong Wei , Derikvand Sara , Javer Amin
Published: June 2020

Ameloblastoma (AM) is a slow growing and aggressive benign tumor with an odontogenic epithelial origin arising from the mandible or maxilla. The odontogenic neoplasm invades local tissues asymptomatically and accounts for 1% of oral tumors and over 10% of odontogenic tumors. A 64-year-old man with a history of allergic fungal rhinosinusitis (AFRS) undergoing a revision image-guided endoscopic sinus surgery was found to have a fibrous mass suspicious of malignancy projecting inferolaterally and attached to the floor of the left maxillary sinus. Diagnostic biopsies were taken, and additional surgery was required to successfully resect the tumor via a transnasal endoscopic dissection. Multiple permanent pathology samples concluded the diagnosis of an AM. Endoscopic investigations led to the incidental discovery and ultimate complete endoscopic resection of the AM. The utilization of an endoscopic resection compared to the traditional maxillectomy with reconstruction results in significant less short and long-term morbidity for the patient.
Hedging, Investment Efficiency, and the Role of the Information Environment
Authors: Lobo Gerald J. , Ranasinghe Tharindra , Yi Lin
Published: June 2020

Extant theories suggest that managers may use hedging either to alleviate underinvestment problems caused by costly external financing or to promote overinvestment by circumventing the scrutiny of external capital markets. We empirically investigate this issue using a hand-collected data set of hedging and investment behavior of oil and gas exploration and production firms. We do not find evidence that hedging alleviates underinvestment problems. However, we do find a strong positive relation between the extent of hedging and the propensity to overinvest. Further analyses indicate that the relation between hedging and overinvesting is stronger in settings where the firms’ information environment is more transparent. A more transparent information environment makes it easier for outside capital providers to distinguish between value-enhancing and value-destroying investment decisions so that greater discretion over internally generated funds becomes more valuable to overinvesting managers. Our study highlights the role of hedging in facilitating overinvestment and the conditions under which this role is likely to be more salient.
Journalism matters: reporting peace in Cyprus
Authors: Şahin Sanem , Karayianni Christiana
Published: June 2020

The article investigates journalism in societies that are working towards a peaceful resolution. Focusing on the ongoing peace process in Cyprus, it studies the influences and difficulties journalists experience when they report on the negotiations. The peace process in Cyprus, which has been divided since 1974 following a conflict between Turkish Cypriots and Greek Cypriots, is continuing. Thematic analysis of the interviews conducted with 67 journalists identifies the key issues that affect journalists in Cyprus when they report on the conflict and peace negotiations. The results show that journalists experience tension between professional values and a sense of belonging and move between professional and national/ethnic identities to cope with it. The results also indicate that despite political and ideological pressures, journalists exercise agency, making attempts to challenge and alter them.
Association Between Helicobacter pylori Infection and Otitis Media With Effusion Risk in Children: A Systematic Review and Meta‐analysis
Authors: Wu Xiaohui , Zheng Yun , Gao Xingqiang , Li Gang , Cao Qiuxue
Published: June 2020

Objective

To investigate the potential correlation between Helicobacter pylori infection and otitis media with effusion (OME) risk in children.

Data Sources

Electronic databases were searched, including Cochrane Library, PubMed, Embase, China Biology Medicine disc, China Science and Technology Journal Database, Wanfang Database, and China National Knowledge Infrastructure Database.

Review Methods

A systematic review and meta‐analysis were conducted with Revman 5.3 software. Combined odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate infection‐disease association.

Results

In total, 11 studies from 9 articles regarding H pylori infection and OME risk were enrolled in this meta‐analysis. A significant association between H pylori infection and OME was detected for both adenoid samples from the case group (OR, 2.75; 95% CI, 1.43‐5.30; P =. 002) and middle ear fluid samples from the case group (OR, 4.45; 95% CI, 2.52‐7.88; P <. 00001). Subgroup analyses suggested a stronger correlation in African and Asian populations.

Conclusion

This study indicated the correlation between H pylori infection and increased risk of OME in children, especially in African and Asian populations. Further well‐designed studies regarding the white population are strongly recommended in the future.
Eustachian Tube Balloon Dilation: A Systematic Review and Meta‐analysis of Treatment Outcomes
Authors: Froehlich Michael H. , Le Phong T. , Nguyen Shaun A. , McRackan Theodore R. , Rizk Habib G. , Meyer Ted A.
Published: June 2020

Objective

To examine the effectiveness of eustachian tube balloon dilation for the treatment of eustachian tube dysfunction.

Data Sources

PubMed, Scopus, and Google Scholar.

Review Methods

A systematic review of eustachian tube balloon dilation for the treatment of eustachian tube dysfunction was conducted following Preferred Reporting Items for Systematic Reviews and Meta‐Analysis (PRISMA) guidelines to identify randomized control trials and prospective and retrospective studies published prior to January 31, 2019. Meta‐analysis of proportions evaluated 7‐item Eustachian Tube Dysfunction Questionnaire (ETDQ7) scores, tympanometry, otoscopy findings, and the ability to perform a Valsalva maneuver.

Results

The systematic review identified 35 studies. Twelve studies met inclusion for meta‐analysis (448 patients). Mean ETDQ7 scores decreased by 2.13 from baseline to 6 weeks (95% CI, –3.02 to −1.24; P <. 001). From baseline to 6 weeks, 53.0% of patients had improvement in tympanograms (P <. 001). At the long‐term point (3‐12 months), 50.5% of patients had improved tympanograms from baseline (P <. 001). There was no significant difference in the proportion of improved tympanograms at 6 weeks compared to long term (P =. 535). Normal otoscopy exams at baseline increased by 30.0% at 6 weeks (P <. 001) and 55.4% in the long term (P <. 001). There was a 67.8% increase in proportion of patients able to perform a Valsalva maneuver in the long term compared to baseline (P <. 001).

Conclusion

Eustachian tube balloon dilation appears to be associated with improvement in subjective and objective treatment outcome metrics. The improvement appears stable at 3 to 12 months after dilation. Patients with eustachian tube dysfunction are likely to benefit from balloon dilation, particularly those with medication‐refractory disease.
Immediate Voice and Swallowing Complaints Following Revision Anterior Cervical Spine Surgery
Authors: Strohl Madeleine P. , Choy Winward , Clark Aaron J. , Mummaneni Praveen V. , Dhall Sanjay S. , Tay Bobby K. , Loftus Patricia A. , El‐Sayed Ivan H. , Russell Matthew S.
Published: June 2020

Objective

To report on the incidence of dysphagia, dysphonia, and acute vocal fold motion impairment (VFMI) following revision anterior cervical spine surgery, as well as to identify risk factors associated with acute VFMI in the immediate postoperative period.

Study Design

Retrospective cohort study.

Setting

Tertiary care center.

Subjects and Methods

All patients who underwent 2‐team reoperative anterior cervical discectomy and fusion (ACDF) were retrospectively reviewed. Incidence of dysphonia, dysphagia, and acute VFMI was noted. Patient and operative factors were evaluated for association with risk of acute VFMI.

Results

The incidence of postoperative dysphonia and dysphagia was 25% (18/72) and 52% (37/72), respectively. The incidence of immediate VFMI was 21% (15/72). Subjective postoperative dysphonia (odds ratio, [OR] 8; 95% CI, 2.2‐28; P =. 001) and dysphagia (OR, 22; 95% CI, 2.5‐168; P =. 005) were significantly associated with increased risk of VFMI. Three patients with VFMI required temporary injection medialization for voice complaints and/or aspiration. Infection (OR, 14; 95% CI, 1.4‐147, P =. 025) and level C7/T1 (OR, 5.5; 95% CI, 1.3‐23, P =. 02) were significantly associated with an increased risk of acute VFMI on multivariate logistic regression analysis. Number of prior surgeries, laterality of approach, side of approach relative to prior operations, and number of levels exposed were not significant.

Conclusion

Early involvement of an otolaryngologist in the care of a patient undergoing revision ACDF can be helpful to the patient in anticipation of voice and swallowing changes in the postoperative period. This may be particularly important in those being treated at C7/T1 or those with spinal infections.
Alternations of Blood Pressure Before and After OSA Surgery
Authors: Tsai Ming‐Hsien , Lin Pei‐Wen , Lin Hsin‐Ching , Friedman Michael , Salapatas Anna M. , Lu Yu‐Hao , Su Mao‐Chang , Lin Meng‐Chih
Published: June 2020

Objective

To investigate the changes of blood pressure (BP) on patients with obstructive sleep apnea/hypopnea syndrome (OSA) before and after upper airway surgery.

Design

Case series with chart review.

Setting

Tertiary academic medical center.

Subjects and Methods

Patients with OSA who underwent upper airway surgery were enrolled. We retrospectively investigated the nighttime and daytime BP before and at least 3 months after OSA surgery. Paired t test was used to compare the changes of BP before and after surgery. Generalized estimating equation was used to examine the prognostic significance of the variables in predicting the changes of postoperative BP.

Results

In total, 176 patients with OSA (149 men, 27 women; mean age, 42.9 years; mean apnea/hypopnea index, 43.1/h) were enrolled in this study. The overall nighttime and daytime BP decreased significantly before and after OSA surgery (daytime systolic BP was reduced from 137.3 ± 14.0 mm Hg to 132.7 ± 17.0 mm Hg, P <. 01; nighttime systolic BP was reduced from 138.7 ± 16.0 mm Hg to 133.7 ± 15.3 mm Hg, P <. 01; daytime diastolic BP was reduced from 87.7 ± 14.7 mm Hg to 84.9 ± 10.6 mm Hg, P =. 01; nighttime diastolic BP was reduced from 85.4 ± 12.9 mm Hg to 83.1 ± 11.1 mm Hg, P =. 02). The changes of nighttime systolic and diastolic BP were significantly associated with the improvement of percentage of O2 saturation <90% during polysomnography.

Conclusion

Surgical modifications of the upper airways for patients with OSA could benefit blood pressure.
Predicting COVID‐19 Incidence Using Anosmia and Other COVID‐19 Symptomatology: Preliminary Analysis Using Google and Twitter
Authors: Panuganti Bharat A. , Jafari Aria , MacDonald Bridget , DeConde Adam S.
Published: June 2020

Objective

To determine the relative correlations of Twitter and Google Search user trends concerning smell loss with daily coronavirus disease 2019 (COVID‐19) incidence in the United States, compared to other severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) symptoms. To describe the effect of mass media communications on Twitter and Google Search user trends.

Study Design

Retrospective observational study.

Setting

United States.

Subjects and Methods

Google Search and “tweet” frequency concerning COVID‐19, smell, and nonsmell symptoms of COVID‐19 generated between January 1 and April 8, 2020, were collected using Google Trends and Crimson Hexagon, respectively. Spearman coefficients linking each of these user trends to COVID‐19 incidence were compared. Correlations obtained after excluding a short timeframe (March 22 to March 24) corresponding to the publication of a widely read lay media publication reporting anosmia as a symptom of infection was performed for comparative analysis.

Results

Google searches and tweets concerning all nonsmell symptoms (0.744 and 0.761, respectively) and COVID‐19 (0.899 and 0.848) are more strongly correlated with disease incidence than smell loss (0.564 and 0.539). Twitter users tweeting about smell loss during the study period were more likely to be female (52%) than users tweeting about COVID‐19 more generally (47%). Tweet and Google Search frequency pertaining to smell loss increased significantly (>2.5 standard deviations) following a widely read media publication linking smell loss and SARS‐CoV‐2 infection.

Conclusions

Google Search and tweet frequency regarding fever and shortness of breath are more robust indicators of COVID‐19 incidence than anosmia. Mass media communications represent important confounders that should be considered in future analyses.
Effect of Implementing Simulation Education on Health Care Worker Comfort With Nasopharyngeal Swabbing for COVID‐19
Authors: Mark Michelle E. , LoSavio Phillip , Husain Inna , Papagiannopoulos Peter , Batra Pete S. , Tajudeen Bobby A.
Published: June 2020

Objective

To determine if rapid implementation of simulation training for the nasopharyngeal swab procedure can increase provider confidence regarding procedure competency.

Methods

A simulation training exercise was designed as a departmental initiative to improve competency performing nasopharyngeal swabs during the COVID‐19 pandemic. Sixty‐one health care workers attended teaching sessions led by the Department of Otorhinolaryngology on proper nasopharyngeal swab technique. After a brief lecture, participants practiced their swab technique using a high‐fidelity airway simulation model. Pre‐ and postintervention self‐evaluations were measured via standardized clinical competency questionnaires on a 5‐point Likert scale ranging from “No knowledge, unable to perform” up to “Highly knowledgeable and confident, independent.”

Results

Forty‐six participants in this study submitted pre‐ and postintervention self‐assessments. Postintervention scores improved on average 1.41 points (95% CI, 1.10‐1.73) out of 5 from a mean score of 3.13 to 4.54 (P <. 0001). This reflects a large effect size with a Glass’s delta value of 1.3.

Discussion

Lecture coupled with simulation‐based teaching can significantly improve health care workers’ confidence in performing nasopharyngeal swabs. Proper training for frontline workers performing swabs for COVID‐19 is essential to improving testing accuracy and can be achieved in a simple and timely manner.

Implications for Practice

To meet the testing needs of the growing pandemic, many health care workers who are unfamiliar with nasopharyngeal swabs have been asked to perform this test. Simulation‐based teaching sessions may improve health care workers’ confidence and help prevent false‐negative results. This intervention is easily reproducible in any setting where frequent nasopharyngeal swab testing occurs.

Level of Evidence/Study Design

Prospective cohort study.
Care of Patients With a Laryngectomy During the COVID‐19 Pandemic
Authors: Yeung David C. M. , Lai Ronald , Wong Eddy W. Y. , Chan Jason Y. K.
Published: June 2020

Patients with a laryngectomy are at increased risk for droplet‐transmitted diseases and, therefore, COVID‐19, which has now caused a worldwide pandemic. Adaptive measures to protect patients with a laryngectomy and their families were designed and implemented in the Hong Kong SAR (HK). Driven by the fear of severe acute respiratory syndrome in 2003, hospitals in HK have since modified infection control routines to prevent a repeat public health nightmare. To face COVID‐19, caused by SARS‐CoV‐2, we have adapted guidelines for our patients with a laryngectomy. Contact precautions, droplet precautions with physical barriers, and hand and equipment hygiene are our mainstays of prevention against COVID‐19, and sharing these routines is the aim of this article. The COVID‐19 pandemic is still roaring ahead. Awareness and precautions for patients with a laryngectomy who may be at higher risk are outlined here and should be maintained during the current pandemic.
Clinical analysis of uterine torsion and fibroids in full-term pregnancy: A case report and review of the literature
Authors: Yin Feng-Ling , Huang Hong-Xiang , Zhang Meng , Xia Xiao-Kun , Xu Hui , Liu Tong , Liu Dan , He Hou-Guang
Published: June 2020

This study was performed to describe the clinical features, risk factors, and treatment methods of uterine torsion in pregnancy. The most common symptoms are abdominal pain, fetal heart rate changes, and failure of cervical dilatation and are often accompanied by complete or partial placental abruption. Preoperative diagnosis is challenging even with the use of ultrasound. Uterine torsion in the third trimester is correlated with the presence of multiple uterine fibroids. The causes of gravid uterine torsion vary and the clinical manifestations are nonspecific. Early diagnosis and improved detection approaches are the keys to treatment of patients with uterine torsion. However, the preoperative diagnosis remains difficult and the diagnosis is often made during cesarean section.
Fracture Properties and Restrained Shrinkage Cracking Resistance of Cement Mortar Reinforced by Recycled Steel Fiber from Scrap Tires
Authors: Shi Xijun , Brescia-Norambuena Leonardo , Grasley Zachary , Hogancamp Joshua
Published: June 2020

Thanks to better processing technology, quality recycled steel fiber (RSF) is routinely extracted from scrap tires, offering opportunities to reinforce cementitious materials in a more economical and sustainable manner. In this study, a detailed experimental program on cement mortar reinforced by up to 2 vol. % RSF was carried out. The work involved conventional tests to characterize cement mortar mechanical properties including compressive strength, elastic modulus, and splitting tensile strength. It also featured an innovative semi-circular bending (SCB) fracture test to characterize fracture-related properties, and a customized ring test to study the cracking resistance under restrained drying shrinkage of the studied mortars. The combined use of the fracture and ring tests is believed to lead to a better assessment of concrete structure behaviors in the field. Based on the test results, the addition of up to 2% RSF shows noticeable improvement on the splitting tensile strength, but it has marginal effects on the cement mortar compressive strength and elastic modulus. The improved fracture properties of the cement mortar reinforced by 2% RSF from the SCB fracture test demonstrate that the RSF-reinforced mortar not only has a better resistance to the initiation of major cracks but also exhibits an enhanced post-cracking performance. Based on the ring test results, the longer cracking time and higher residual strain level of the 2% RSF mortar samples clearly reveal that the RSF could effectively delay and bridge cracks.
Respiratory Dysfunction and Sleep-Disordered Breathing in Children With Myasthenia Gravis
Authors: Katzberg Hans D. , Vajsar Jiri , Vezina Kevin , Qashqari Heba , Selvadurai Sarah , Chrestian Nicholas , Khayat Abdullah , Ryan Clodagh M. , Narang Indra
Published: June 2020

Objectives:

The purpose of this study was to prospectively evaluate sleep patterns and the presence of sleep-disordered breathing in children with myasthenia gravis. We further aimed to examine the relationship between sleep and daytime respiratory function using spirometry tests including upright and supine forced vital capacity, sniff nasal inspiratory pressure, and maximal inspiratory pressure.

Methods:

Eleven children between 3 and 18 years old with confirmed myasthenia gravis were recruited from The Hospital for Sick Children Neuromuscular Clinic in this prospective observational study. After informed consent was obtained, patients underwent a comprehensive clinical assessment with collection of anthropometric data. Following this, all subjects performed pulmonary function tests, overnight polysomnography and completed the Epworth Sleepiness Scale questionnaire.

Results:

Two of eleven children who reported no symptoms of sleep disordered breathing were diagnosed with mild to moderate obstructive sleep apnea. Pulmonary function tests showed abnormal maximal inspiratory pressure in 6 of 11 patients, whereas seated forced vital capacity as well as seated to supine forced vital capacity ratios were normal in the entire group.

Conclusions:

In our small group of pediatric myasthenia gravis subjects, there was an unexpected finding of obstructive sleep apnea in 2 of the 11 patients studied. Maximal inspiratory pressure appears to be a more sensitive method of detecting abnormalities compared to upright or seated forced vital capacity. A larger multicenter study is needed to validate our findings and to determine the impact of obstructive sleep apnea in the pediatric myasthenia gravis population as well as risk factors associated with sleep disordered breathing.
Prevalence and Risk Factors of Elder Mistreatment in Sheltered Homes
Authors: Alraddadi Khulood
Published: June 2020

Elder mistreatment is common in both community and institutional settings. However, the prevalence of elder mistreatment and its association with risk factors in sheltered homes are unknown. The primary objective of this study was to determine the prevalence and types of mistreatment among elderly living in sheltered homes. A second objective was to compare socio-demographics and other characteristics between elderly groups with or without a history of mistreatment. This cross-sectional study was conducted in 43 sheltered homes and utilized a face-to face, self-reporting interview with residents to complete structured question regarding each participant’s previous 12 months. The questionnaires included seven sections, including one section for demographics, five sections for subtypes of mistreatments (physical, psychological, financial, sexual, and neglect), and one section about health status and functional capacity. Among the 446 elderly participants, 81% of all participants experienced at least one type of mistreatment. Psychological was the most common type of elder mistreatment (71%), followed by neglect (67%), financial mistreatment (54%), and physical mistreatment (13%). Sexual mistreatment was rarely reported by the participants (0.01%). The most common risk factors associated with elder mistreatment were female gender and chronic illnesses. Elder mistreatment is common among the elderly living in sheltered homes, particularly in woman and those with chronic illness. Further studies are needed to better understand the risk factors that lead to the high prevalence of mistreatment in these settings.