minimum frequency
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GYNECOLOGY ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. 435-440
Author(s):  
Mekan R. Orazov ◽  
Viktor E. Radzinsky ◽  
Ljudmila M. Mihaleva ◽  
Elena S. Silantieva ◽  
Marina B. Khamoshina ◽  
...  

The most urgent problem of modern gynecology is not just the treatment of intrauterine adhesive disease in fertile women, but the prevention of its recurrence. The lack of a systematic approach to management create grounds for searching for remedies with maximum anti-relapse effectiveness, minimum frequency of side effects. The purpose of the review is to consider the effectiveness of various types of treatment of intrauterine adhesions in women of reproductive age.


Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5961
Author(s):  
Sung-Eun Kim ◽  
Yeong-Han Chun

In recent years, the need for generation mixes that consider the inertial constraints in unit commitment (UC) has increased because the inertia of these systems has decreased with the increased use of renewable energy. In these circumstances, single-machine models can calculate the minimum frequency and rate of change of frequency (RoCoF) at a high speed in terms of the characteristics of the changes in the generation mix, in order to identify the generation mixes that can satisfy inertial constraints. This study proposed methods to determine the parameters of the reduced frequency response (RFR) model, which is a single-machine model that considers the nonlinearity caused by restrictions on the generator’s output power, in order to apply inertial constraints to UC. The RFR models can include various forms of governor models and consider the nonlinear response characteristics of restrictions on the generator’s output power that change according to the scales of contingencies, system inertia, and changes in load characteristics through these parameters. From the simulations of real systems, it was observed that the parameters determined through the proposed methods achieved considerable accuracy in calculating the minimum frequency and RoCoF with the RFR model.


2021 ◽  
Vol 61 ◽  
pp. e20216159
Author(s):  
Ronan de Azevedo Monteiro ◽  
Carolina Demetrio Ferreira ◽  
Gilmar Perbiche-Neves

Vocal plasticity reflects the ability of animals to vary vocalizations according to context (vocal repertoire) as well as to develop vocal convergence (vocal group signature) in the interaction of members in social groups. This feature has been largely reported for oscine, psittacine and trochilid birds, but little has been investigated in birds that present innate vocalization. The smooth-billed ani (Crotophaga ani) is a social bird that lives in groups between two and twenty individuals, and which presents innate vocalization. Here we analyzed the vocal repertoire of this species during group activities, and further investigated the existence of a vocal group signature. The study was conducted in the Southeast of Brazil between May 2017 and April 2018. Two groups of smooth-billed anis were followed, Guararema and Charqueada groups, and their vocalizations were recorded and contextualized as to the performed behavior. The vocal repertoire was analyzed for its composition, context and acoustic variables. The acoustic parameters maximum peak frequency, maximum fundamental frequency, minimum frequency, maximum frequency and duration were analyzed. To verify the vocal signature of the group, we tested whether there was variation in the acoustic parameters between the monitored groups. We recorded ten vocalizations that constituted the vocal repertoire of the Smooth-billed Ani, five of which (“Ahnee”, “Whine”, “Pre-flight”, “Flight” and “Vigil”) were issued by the two groups and five exclusive to the Charqueada group. There were significant differences in the acoustic parameters for “Flight” and “Vigil” vocalizations between the groups, suggesting vocal group signature for these sounds. We established that the Smooth-billed Ani has a diverse vocal repertoire, with variations also occurring between groups of the same population. Moreover, we found evidence of vocal group signature in vocalizations used in the context of cohesion, defense and territory maintenance.


Author(s):  
Padmini Nigam ◽  
Arjuna Muduli ◽  
Sandeep Sharma ◽  
Amrindra Pal

In this letter, an efficient and electrically compact cavity-backed self-triplexing antenna using a substrate integrated waveguide (SIW) technique is proposed. The antenna model is nested with an inverted “T”-shaped cavity and convert the rectangular SIW cavity into the two quarter mode (QM) and a half mode cavity (HM) approximately; excited through a coax probe and two micro-strip feed line separately. The proposed model operates at three distinct frequencies at 9.37 GHz, 9.86 GHz, and 10.36 GHz used for X-band wireless and radar communication systems. The self-triplexing feature is obtained with the mode perturbation concept and adequate intrinsic isolation of >31 dB is observed among three input ports. The proposed antenna possesses a minimum frequency ratio, uni-directional radiation patterns with high gain, and better efficiency.


Author(s):  
Razieh Gholaminejad ◽  
Mohammad Reza Anani Sarab

In this commentary, we begin with the discussion on a brief history of academic wordlists. Adopting a comparative perspective, then, the merits and demerits of the Academic Word List (AWL) (Coxhead, 2000) and its competing counterpart the Academic Vocabulary List (AVL) (Gardner & Davies, 2014) are presented. We also explore whether the AWL can still be considered as “the best list” (Nation, 2001, p. 12) for improving academic words, or whether its counterpart is reasonably “the most current, accurate, and comprehensive list” (Gardner & Davies, 2014, p. 325). The comparison was made in terms of twelve aspects: corpus size, types of corpus texts, sources of corpus texts, text balance, disciplines included, counting unit, wordlist items, method for excluding highfrequency words, minimum frequency, method for excluding technical words, sequence of list items and lexical coverage. The comparison reveals that the AVL is far from complete and cannot replace the AWL. The results of the comparison can have implications for practitioners and course developers.


2021 ◽  
Author(s):  
Irina Logvinenko ◽  

Abstract: Various clinical scenarios of the course of the post-COVID syndrome in the period of convalescence were studied. The frequency and volume of studies in combined pathology in patients who have undergone COVID-19 are considered. The controlled indicators of the medical state within the framework of follow-up monitoring and the minimum frequency of follow-up visits were clarified. Key words: New coronavirus infection, convalescents, the long COVID syndrome, follow-up monitoring


Author(s):  
Anya Selwyn ◽  
Jeremy Davis ◽  
Robert Hone

Key Points: 1. We have identified ambiguity in the current guidance on thyroid MDT’s, and have also found nationwide variation in compliance with this. 2. We recommend: a. All surgeons undertaking thyroid surgery should complete a minimum of 20 thyroid procedures per year, and this should also form part of surgeons’ annual appraisal. b. All surgeons should contribute data to UKRETS (unless prevented by local legal frameworks) and this should form part of surgeons’ annual appraisal and be audited by individual MDT’s and regional cancer networks. c. Thyroid MDT’s should be held weekly where possible, with a minimum frequency of fortnightly. d. The core membership of a thyroid MDT (stand alone and joint) should include thyroid surgeons, specialist radiology, endocrinology, nuclear medicine, nurse specialists, histopathology +/- cytology and clinical oncology.


2021 ◽  
pp. 1-12
Author(s):  
Tobias Dienerowitz ◽  
Thomas Peschel ◽  
Mandy Vogel ◽  
Tanja Poulain ◽  
Christoph Engel ◽  
...  

<b><i>Purpose:</i></b> The purpose of this study was to establish and characterize age- and gender-specific normative data of the singing voice using the voice range profile for clinical diagnostics. Furthermore, associations between the singing voice and the socioeconomic status were examined. <b><i>Methods:</i></b> Singing voice profiles of 1,578 mostly untrained children aged between 7.0 and 16.11 years were analyzed. Participants had to reproduce sung tones at defined pitches, resulting in maximum and minimum fundamental frequency and sound pressure level (SPL). In addition, maximum phonation time (MPT) was measured. Percentile curves of frequency, SPL and MPT were estimated. To examine the associations of socioeconomic status, multivariate analyses adjusted for age and sex were performed. <b><i>Results:</i></b> In boys, the mean of the highest frequency was 750.9 Hz and lowered to 397.1 Hz with increasing age. Similarly, the minimum frequency was 194.4 Hz and lowered to 91.9 Hz. In girls, the mean maximum frequency decreased from 754.9 to 725.3 Hz. The mean minimum frequency lowered from 202.4 to 175.0 Hz. For both sexes, the mean frequency range ∆f showed a constant range of roughly 24 semitones. The MPT increased with age, for boys and girls. There was neither an effect of age nor sex on SPL<sub>min</sub> or SPL<sub>max</sub>, ranging between 52.6 and 54.1 dBA and between 86.5 and 82.8 dBA, respectively. Socioeconomic status was not associated with the above-mentioned variables. <b><i>Conclusion:</i></b> To our knowledge, this study is the first to present large normative data on the singing voice in childhood and adolescence based on a high number of measurements. In addition, we provide percentile curves for practical application in clinic and vocal pedagogy which may be applied to distinguish between normal and pathological singing voice.


2021 ◽  
Vol 66 (1) ◽  
pp. 56-61
Author(s):  
L. E. Nazarov ◽  
A. S. Zudilin ◽  
V. I. Kaevitser ◽  
I. V. Smolyaninov

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