bluuebunny/crossref_metadata_2025 huggingface dataset:
8 Effects of magnetic-activated cell sorting on human sperm motility and DNA fragmentation index
Authors: Toishibekov Y. M. , Baikoshkarova S. B. , Assanova Y. A. , Otarbayev M. K. , Komogortsev A. N. , Nekhorosheva V. A. , Tokubayeva A. A. , Battalov B. P. , Toishybek D. Y.
Published: January 2021

Selection of spermatozoa before their use for assisted reproductive techniques is an important step in therapy of human infertility. The DNA fragmentation index of sperm plays a major role in pregnancy rates following IVF and intracytoplasmic sperm injection (ICSI). Sperm analyses and standard sperm selection methods in many cases do not eliminate a sufficient proportion of sperm with apoptosis and DNA fragmentation. Magnetic-activated cell sorting (MACS) is a selection method that eliminates apoptotic spermatozoa based on the presence of externalized phosphatidylserine residues. The aim of our study was to evaluate the effect of MACS on human sperm motility and DNA fragmentation index (DFI) in a patient population. The participants were 63 male patients of an IVF clinic, 34 to 45 years old, with 3 years of primary infertility due to male factor. Semen analysis was performed according to the World Health Organization guidelines (2010) and revealed oligoasthenoteratozoospermia in 63 patients. The DFI of fresh semen samples was evaluated using the sperm chromatin structure assay (SCSA) test and revealed DFI 32.4±5.9%. The SCSA test was done on a flow cytometer CyFlow Space (Sysmex-Partec; Evenson 2016 Anim. Reprod. Sci. 169, 56-75; https://doi.org/10.1016/j.anireprosci.2016.01.017). Sperm motility was studied on Hamilton Thorne IVOS. For MACS, we used the MACS® ART Annexin V system (Miltenyi Biotec). The semen sample was diluted to a concentration 10×106 spermatozoa mL−1. After double-density gradient centrifugation, the pellet was resuspended in 100µL of MACS Art Annexin V reagent and added MACS Art Binding Buffer (BB) to 500µL. The sample was gently mixed and incubated for 15min at room temperature. After rinsing the column with BB, the sperm-bead suspension was added on top with BB and, immediately after that, the annexin V-negative and annexin V-positive fractions were obtained (MiniMACS; Miltenyi Biotec). Data were evaluated by ANOVA Student’s t-test. Fresh semen samples collected from the patients had an average sperm concentration of 29.7±5.7×106 mL−1, motility of 32.7±5.9%, and DFI of 32.4±5.9%. Motility of spermatozoa after MACS for the annexin-negative fraction was 47.2±6.3% and for the annexin-positive fraction was 3.5±2.3% (P<0.003). Similarly, the annexin-negative spermatozoa had a lower DFI (10.5±3.8%) rate than did the annexin-positive fraction (67.8±5.9%; P<0.003). The MACS technique allowed a significant reduction of DNA fragmentation levels (from 32.4% for the original sample to 10.5% for the annexin-negative; P<0.01). The separation of a distinct population of nonapoptotic spermatozoa with intact membranes may optimize outcomes from IVF and ICSI procedures. Magnetic-activated cell sorting of human sperm using annexin-V microbeads results in selection of a population with enhanced motility and reduced DFI rates.
95 Invitro correction of F508del and G542X mutations in sheep fibroblasts of cystic fibrosis models
Authors: Bunch K. , Perisse I. V. , Fan Z. , White K. , Polejaeva I.
Published: January 2021

Cystic fibrosis (CF) is a human genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. Among the ∼2000 known CF mutations, the F508del mutation is found in 84% and G542X in 4.6% of the CF patients in the United States. The F508del mutation occurs in exon 11 and is characterised by deletion of the “CTT” nucleotides, resulting in deletion on the phenylalanine residue at the position 508 of CFTR. This causes misfolding of the CFTR protein, which is further degraded by proteases. The G542X mutation is a nonsense mutation found in exon 12 and associated with nonsense-mediated decay of the mutant transcript causing the absence of protein production. Previously, we generated CFTRF508del/F508del and CFTRG542X/G542X lambs (unpublished) using CRISPR/Cas9 and somatic cell nuclear transfer (SCNT) techniques. We hypothesised that gene editing may be an effective tool to correct these mutations and permanently cure this genetic disease. Thus, in this study, we evaluated the efficiency of CRISPR/Cas9-meditated gene knock-in to correct the F508del and G542X mutations in sheep fibroblasts invitro. We designed single guide (sg)RNAs using the Benchling software (https://benchling.com/academic) and approximately 100bp of single-stranded oligodeoxynucleotides (ssODNs) targeting the mutation sites at exon 11 and 12 to introduce either “CTT” or change the “T” to “G” nucleotide in genome of F508del or G542X CF sheep cells, respectively. Each of Cas9/sgRNA ribonucleoproteins was transfected into sheep fibroblast cells along with ssODNs using the Lonza-4D-NucleofectorTM (Lonza) system for homology-directed repair. The transfected cells were subsequently cultured in Dulbecco’s modified Eagle medium, supplemented with 15% fetal bovine serum and 1% penicillin, and incubated at 38.5°C. DNA was extracted 48h post-transfection to validate mutation efficiency. PCR products of the exons 11 and 12 were ligated into T-vector, and bacterial colonies were selected based on blue/white screening. In total, we isolated 32 single cell bacterial colonies for each mutant. Sequencing results indicate that “CTT” was introduced in 4/26 (15.3%) plasmid colonies, and “T to G” replaced in 13/31 (41.9%) colonies. Therefore, our results indicate that the F508del and G542X mutations can be effectively corrected in CF sheep fibroblasts invitro using a CRISPR/Cas9 approach.
Prosodic transfer across constructions and domains in L2 inflectional morphology
Authors: Austin Gavin , Chang Heejin , Kim Nayoung , Daly Eoin
Published: January 2021

Second language (L2) learners are known to have difficulty producing inflection in obligatory contexts reliably. According
to the Prosodic Transfer Hypothesis (PTH), the prosodic organisation of L2 inflection is constrained by the inventory of representations
available in the L1. At the same time, this hypothesis does not explicitly limit how freely prosodic representations can be transferred, so
that transfer across constructions within the same domain (e.g., verbal domain: L1 tense → L2 agreement) and across domains (e.g., verbal
domain: L1 tense → nominal domain: L2 plurals) are both possible in principle. The goal of this study was to determine if the current
formulation of the PTH is valid, or must be reined in to exclude transfer across domains in particular. Forty-four Korean learners of
English did a spoken sentence-construction task in which they had to produce subject-verb agreement and regular plural inflection. Bayesian
hierarchical regression was used to analyse the results. By examining asymmetries in the suppliance of short- vs. long-stemmed inflection,
we show that there are no grounds for attaching any stipulations to the PTH along the above lines, as prosodic representations are
transferrable not only across constructions but also across domains.
Le Nouveau conseil de Smil Flaška de Pardubice
Authors: Adde Éloïse
Published: January 2021

Abstrait

Œuvre didactique qui tient tant du bestiaire, de la satire, du miroir au prince que de l’œuvre d’édification religieuse, le Nouveau conseil fait partie des grands textes de la littérature médiévale de langue tchèque. Rédigé en 1394–1395 par le seigneur Smil Flaška de Pardubice, actif partisan du mouvement de l’Union seigneuriale qui s’était opposé au roi, ce texte a souvent été analysé pour son contenu factuel (historique et politique) comme une critique du gouvernement de Venceslas IV. À travers une lecture anthropologique qui interroge l’utilisation du bestiaire, cet article propose de restituer l’épaisseur du message du Nouveau conseil, sa conception de l’homme et de sa place dans le monde (aspects sociaux) ainsi que dans la perspective de la providence. Plus qu’une satire, l’œuvre nous livre une représentation complexe de l’individu, à la charnière entre monde divin et monde terrestre, les animaux permettant de dire l’humanité dans sa diversité, l’individu dans sa singularité, et la personne dans sa complexité.
On the borders of humanity
Authors: Cipriani Mattia
Published: January 2021

The Liber de natura rerum is a thirteenth-century encyclopedia that reflects the naturalistic interests
of its author, the Dominican friar Thomas of Cantimpré (ca.1200/ 01–ca.1270/ 72). Despite his realistic
focus, Thomas was a man of his time and he introduced elements in his work that may seem bizarre to a modern reader. The purpose of this
article is twofold. Firstly, it analyses how the Friar treats these different elements, whether they were widespread in thirteenth-century
culture (e.g. Amazons, wild men, mermaids, etc.) or discussed for the first time by the Thomas himself (e.g. giants of Vienna, wolf-girl of
Burgundy, etc.). Secondly, the paper highlights some very interesting and new aspects of Thomas’s work that shed light on his way of
thinking and on his encyclopedia.
Mnemonic verses concerning animals and birds in Cambridge University Library, Ms Oo. Vii.48
Authors: Dines Ilya
Published: January 2021

This article is devoted to an essentially unknown fragment containing a collection of thirteenth-century mnemonic verses
about animals and birds. It is a logical continuation of a study I published in 2010 in Reinardus about the entire corpus
of mnemonic verses that appear in medieval Latin bestiaries. As the core of that investigation, I chose a late thirteenth-century English
bestiary of the so-called Second Family (Oxford, Bodleian Library, MS Bodley 533). In that article I suggested that further
research would likely uncover more such examples in non-bestiary manuscripts. This was confirmed in 2018 by a newly discovered fragment in
Cambridge University Library, MS Oo.vii.48, containing the verses present in MS Bodley 533, and additional verses about animals and birds.
Using this fragment, I put forward the idea that there was an established medieval tradition of collecting and keeping organized mnemonic
verses devoted to animals and birds. I argue that finding these verses from bestiaries and other sources together in one fragment sheds
light on the interrelations of bestiaries and other genres.
Tracking the Mysterious Loz in the Secrets of Natural History
Authors: Friedman John Block
Published: January 2021

The loz is a bovid that in medieval folklore was believed to live in Bohemia. It defended itself against hunters by spraying them with boiling and corrosive water stored in a dewlap beneath its neck. First appearing in the learned tradition with Bartholomaeus Anglicus’ De proprietatibus rerum, it then shows up in a richly illustrated geographical and wonders treatise, the Secrets of Natural History (SNH) of about 1380. This work is a Middle French translation of a small portion (on wonders of various regions of the world) of Pierre Bersuire’s exempla collection Reductorium Morale. The only visual representations of the loz are to be found in the SNH. I argue that both in its written and in its visual existence, the loz is the offspring of two different animals, also more or less imaginary, the bonnacon of the Bestiary and the other, the onager, or wild ass, though a very unusual form of that animal.
What are they saying?
Authors: Šorm Martin
Published: January 2021

The study presents the interpretative history of the poem New Council written by the author Smil
Flaška in the 1390s. It argues against accents on its determinative connection with the Czech political history; instead it
promotes interpretation based on research of the ways it documents on representations of piety or the social, ethical, or
environmental imagination of the late 14th and 15th centuries. Concentrating on the manuscript context (three codices from the
latter half of the 15th century) as well as on reception of the poem in the 16th century, the study demonstrates that at the time
the poem was transcribed and read, it functioned not as an exclusive lesson for the upper classes or as criticism of the king, but
as a long-tried-and-tested edutaining text, accessible to recipients from various social groups. The New
Council is a synecdochal representation of the created world, wherein birds and animals compel the reader to
relinquish the misleading categories of allegory, irony or satire and submit to the actual subjective effects of God’s word coming
from non-human mouths. The recipient is invited to enter the space between man and animal, as the animals’ utterances based on religious teaching lead to a transformation of his conscience and perception.
Strong gravity effects of charged Q-clouds and inflating black holes
Authors: Brihaye Yves , Hartmann Betti
Published: January 2021

In this paper, we re-examine chargedQ-clouds around spherically symmetric, static black holes. In particular, we demonstrate that for fixed coupling constants two different branches of charged scalar clouds exist around Schwarzschild black holes. This had not been noticed previously. We find that the new solutions possess a ‛hard wall’ at maximal possible gauge coupling. This wall separates the interior (containing the black hole horizon), in which the scalar field is trapped in the ‛false vacuum’, from the ‛true vacuum’ exterior. When taking back-reaction onto the space-time into account, we find that at maximal possible back-reaction, the black hole solutions corresponding to these two branches either become extremal black holes with diverging scalar field derivative on the horizon or inflating black holes with a second, ‛cosmological’ horizon which—outside this second horizon—correspond to extremal Reissner–Nordström black holes.
Investigating the role of oxygen and related defects in the self-biased and moderate-biased performance of β-Ga2O3 solar-blind photodetectors
Authors: Arora Kanika , Kumar Naveen , Vashishtha Pargam , Gupta Govind , Kumar Mukesh
Published: January 2021

High-performance, low-cost, self-powered deep-ultraviolet photodetectors (DUV-PDs) are essential for military and civil applications. β-Ga2O3 stands alone among all the solar-blind materials in its suitability for use in next-generation DUV-PDs. However, deep traps by oxygen vacancies critically affect the photogenerated carriers, and hence the photodetector’s final efficiency. Notwithstanding, both a lack of and an excess of oxygen in β-Ga2O3 ultimately lead to leakage channels, carrier scattering and sub-bandgap absorption. However, no studies on the impact of extremes of oxygen (oxygen-poor and oxygen-rich) on β-Ga2O3 photodetector efficiency are available in the literature. Therefore, in the present work, we aim to understand the impact of varied oxygen flow rates from 0% to 4% on material properties and photodetector performance. Photoluminescence, time-resolved photoluminescence (TRPL), x-ray photoelectron spectroscopy and the electrical properties of fabricated photodetectors confirmed the critical role of oxygen in β-Ga2O3. TRPL measurements revealed that β-Ga2O3 with 1% oxygen flow had a reported shortest decay time of nearly 50 ps. A very low dark current of 0.9 pA and a maximum photo-to-dark current of >103 were achieved at zero bias for β-Ga2O3 under optimum oxygen flow. The responsivity, external quantum efficiency, detectivity and dark current for a sample at moderate bias fabricated under optimum oxygen flow were found to be 190.08 A W−1, 9.42 × 104%, 1.22 × 1015 Jones and 21 nA, respectively. Hence, the measurements showed that for better device performance and self-powered response, oxygen concentrations that are neither too low nor too high are needed, and the detailed mechanism behind this is discussed. Comparison of the figures of merit with those of other reported devices in both self-powered and high bias mode reveals the far superior performance of the present device.
First-principle investigation of all types of topological nodal lines in a realistic P63/mmc type titanium selenide
Authors: Li Yang , Xia Jihong , Khenata Rabah , Kuang Minquan
Published: January 2021

Topological nodal line (TNL) materials with one-dimensional band-crossing points (BCPs) exhibit interesting electronic characteristics and have special applications in electronic devices. Normally, based on the slopes of the crossing bands, the BCPs can be divided into two types, i.e., type I and type II nodal points. Based on the combination of the different types of nodal points, the nodal lines (NLs) can be divided into three categories: (i) type I NL, type II NL, and hybrid NL, these being formed by type I nodal points, type II nodal points, and type I and II nodal points, respectively. Compared with the large number of predicted type I NL materials, there are less type II and hybrid NL materials. In this study, it is predicted that P63/mmc type TiSe metal is a topological material which exhibits all types of NL states. Furthermore, the dynamic stability as well as the effect of spin–orbit coupling on the topological signatures are examined. Also, the nontrivial surface states are shown to provide evidence for the occurrence of the NL states. This novel material can be seen as a good platform to use for further investigations on the three types of NLs and diverse fermions.
Performance evaluation of the mouse version of the LabPET II PET scanner
Authors: Gaudin Émilie , Thibaudeau Christian , Arpin Louis , Leroux Jean-Daniel , Toussaint Maxime , Beaudoin Jean-Francois , Cadorette Jules , Paillé Maxime , Pepin Catherine M , Koua Konin , Bouchard Jonathan , Viscogliosi Nicolas , Paulin Caroline , Fontaine Réjean , Lecomte Roger
Published: January 2021

The LabPET II is a new positron emission tomography technology platform designed to achieve submillimetric spatial resolution imaging using fully pixelated avalanche photodiodes-based detectors and highly integrated parallel front-end processing electronics. The detector was designed as a generic building block to develop devices for preclinical imaging of small to mid-sized animals and for clinical imaging of the human brain. The aim of this work is to assess the physical characteristics and imaging performance of the mouse version of LabPET II scanner following the NEMA NU4-2008 standard and using high resolution phantoms and in vivo imaging applications. A reconstructed spatial resolution of 0.78 mm (0.5 μ
l) is measured close to the center of the radial field of view. With an energy window of 350 650 keV, the system absolute sensitivity is 1.2% and its maximum noise equivalent count rate reaches 61.1 kcps at 117 MBq. Submillimetric spatial resolution is achieved in a hot spot phantom and tiny bone structures were resolved with unprecedented contrast in the mouse. These results provide convincing evidence of the capabilities of the LabPET II technology for biomolecular imaging in preclinical research.
A low turn-on voltage AlGaN/GaN lateral field-effect rectifier compatible with p-GaN gate HEMT technology
Authors: Wang Fangzhou , Chen Wanjun , Wang Zeheng , Wang Yuan , Lai Jingxue , Sun Ruize , Zhou Qi , Zhang Bo
Published: January 2021

In this paper, we designed a low turn-on voltage (V
On) AlGaN/GaN lateral field-effect rectifier (LFER) compatible with p-GaN gate high-electron-mobility transistor (HEMT) technology (PG-LFER). We also established an analytical model on the gated control two-dimensional-electron-gas density (n
S) distributions and V
On to investigate the underlying mechanism. The designed PG-LFER features a p-GaN charge storage layer (CSL) under the anode terminal. Net negative charge density in the p-GaN CSL (σ
p-GaN) is associated with the activated doping concentration of p-GaN CSL (N
p-GaN) and p-GaN CSL thickness (t
p-GaN). V
On of the PG-LFER is significantly lowered due to the low σ
p-GaN caused by reducing the N
p-GaN and t
p-GaN. Meanwhile, the low V
On PG-LFER also preserves recognizable reverse blocking and capacitance characteristics. Verified by the calibrated simulation, the designed PG-LFER shows 70% lower V
On compared with the non-optimized LFER with a high σ
p-GaN. Compatible with p-GaN gate HEMT technology, the designed PG-LFER with improved performance is a promising candidate for power integrated applications.
Identification and Prevention of Accidents Using Smart Helmet and GPS System
Authors: Shalini S , Muruganandham J , Surya S
Published: January 2021

In each one hour 17 people are dying in India because of street mishaps. According to the administration report practically 1.5 lacks people are passed on street mishaps in 2017.Most of mishaps is bikes in view of person not worn helmet and consuming alcohol. So in this proposed framework if the rider isn’t worn helmet or consumes any alcoholic substance is distinguished, the bike will not start. In addition, it has a smart feature to identifying accidents and sends SMS to rescue vehicle, police headquarters and family members with location by using GSM and GPS module, thus aiding ambulance to reach the correct location. We want to integrate all the sensors inside the helmet, which will send the all the data to the receiver connected in motorcycle wirelessly. This brilliant head protector framework comprises of two modules, one is head protector(transmitter) and another one is bike (receiver). Alcohol sensor, IR sensor and ultrasonic sensor are associated inside the helmet unit and vibration sensor, GPS and GSM are connected in vehicle unit. The transmitting and receiving unit communicate wirelessly using RF transmitter and receiver, using arduino.
An Energy Efficient Sleep and Wake-up Scheduling Approach in Heterogeneous Networks
Authors: Vasanthi D. , Sivasakthi T. , Lakshmy N. , Sathyavathi V.
Published: January 2021

In current years, there is an sudden increase of wireless data Traffic which has resulted in a huge scale dense deployment of small cells, with which the increasing cost of energy has concerned a set of research interest. I present the wireless network which consists of distributed sensor nodes. The function of distributed sensor nodes is to manage the physical condition and to generate the traffic system. Each and every nodes in WSN will sends and receives the packet ensuing in depletion of bandwidth. However, bandwidth sensor nodes are not an productive by saving the energy. Thus, sleep/wake-up scheduling is one of the vital problems in the wireless sensor network. Because, they are fixed and it cannot be recharge again. An energy efficient sleep/wake-up scheduling approach is proposed. The aim of this approach is to save the energy of each nodes and to increase their lifetimes.
Advanced PIC Technologies and Recent Simulation Tools: A Survey
Authors: Bhuvaneshwari K. , Elizabeth Caroline B.
Published: January 2021

Nowadays, electronics were completely replaced by photonics as a result of substantial growth in Photonic Integrated Circuits (PICs). The expansion of photonics on various platforms such as III-V integration, silicon photonics, polymer integration and lithium Niobate techniques were reviewed and the parameters like bandwidth, data rate and bit error rate were analyzed on time and frequency domains. A study of the Photonic integration software was included such as Lumerical interconnect to interconnect PIC simulator and the co-simulation software OPTSIM tool.
Survey for Dependent on Neuro Fuzzy Algorithm for Framework ID
Authors: Umadevi S. , Namratha B.V.K.
Published: January 2021

This article focuses on hybrid neuro-fuzzy techniques, its advantages and disadvantages. The techniques of fuzzy logic and neural networks are commonly used for artificial intelligence. At the point when they are utilized in a joined manner, they are called Neuro-Fuzzy Systems. In the Neuro-Fuzzy Systems fuzzy sets and fuzzy rules are adjusted using input output patterns. The Neuro-fuzzy systems are implemented by different authors in different models. The Neuro-Fuzzy frameworks have the accompanying attributes: quick learning, versatility on-line, to modify itself with the point of getting the little worldwide blunder conceivable and little computational multifaceted nature. The obtaining of information, the pre-handling of information and preparing information are additionally significant for the achievement of the use of the neuro-fuzzy models
Effect of smart environmental elements on occupancy rates of subsidy housing in North Balikpapan District
Authors: Ulimaz M , Syafitri E D
Published: January 2021

In line with the decline of mining and oil business since 2015, the purchasing power of the middle and upper class houses of Balikpapan City residents has also decreased. Property developers change strategy by developing low-cost and subsidies housing. However, often the end result of the construction of cheap housing is still not built environmentally. It is very important to consider environmentally friendly housing. Many of these subsidy housing developments are built in North Balikpapan District. Based om the existence of subsidy housing in Balikpapan Utara that is already built and inhabited, it is necessary to identify the influence of smart environment elements on the occupancy rates of existing subsidy housing in order to improve environmental quality. The analysis of the occupancy rate of subsidy houses based on smart environmental elements is carried out through a linear regression model. The results of the analysis show that there are only 2 significant variables, distance of arterial roads and the affordability of religious facilities. If the affordability of arterial roads increases by one unit, then the number of houses occupied will increase by 15%. If the affordability of religious facilities increases, the number of houses occupied will increase by 74%.
Titanium and titanium based alloy prepared by spark plasma sintering method for biomedical implant applications—a review
Authors: Annur Dhyah , Kartika Ika , Supriadi Sugeng , Suharno Bambang
Published: January 2021

Titanium has been widely used in biomedical implant applications due to its excellent mechanical properties and biocompatibility. However, manufacturing titanium was quite challenging due to the need for high temperature while having high reactivity. Therefore, spark plasma sintering (SPS) is proposed as an advance rapid sintering technique which allows the fabrication of bulk and porous titanium for biomedical application. This review aims to explore the recent status of titanium alloys prepared by the SPS method. There are two common approaches of titanium development by the SPS method, develop a bulk titanium alloy, or develop porous titanium. The development of titanium for biomedical implant application was done by improving biocompatibility alloy and repair some unsatisfactory mechanical properties. Some low toxicity of titanium alloys (Aluminum free and Vanadium free) had been studied such as Ti–Nb, Ti–Zr, Ti–Ag, Ti–Mg, Ti–Nb–Zr, Ti–Nb–Cu, Ti–Nb–Zr–Ta, etc. SPS was shown to increase the mechanical properties of titanium alloys. However, porous titanium alloys prepared by SPS had gained much attention since it may produce titanium with lower elastic modulus in such a short time. Low elastic modulus is preferable for implant material because it can reduce the risk of implant failure due to the stress-shielding effect. Besides mechanical properties, some corrosion resistance and the biocompatibility of titanium are also reviewed in this paper.
Blunted beta-adrenoceptor-mediated inotropy in valvular cardiomyopathy: another piece of the puzzle in human aortic valve disease
Authors: Petersen Johannes , Kloth Benjamin , Iqbal Shahria , Reichenspurner Hermann , Geelhoed Bastian , Schnabel Renate , Eschenhagen Thomas , Christ Torsten , Girdauskas Evaldas
Published: January 2021

OBJECTIVES

Heart failure induced by valvular cardiomyopathy occurs in a substantial proportion of patients undergoing heart valve surgery. We aimed (i) to quantify beta-adrenoceptor (beta-AR) function by measuring the inotropic effect of isoprenaline in left ventricular (LV) tissue and (ii) to correlate beta-AR-mediated inotropy with clinical markers of heart failure.

METHODS

A total of 179 LV myocardial samples were obtained from 104 consecutive patients who underwent aortic valve (AV) surgery between 2017 and 2019. Beta-ARs were stimulated by increasing the concentrations of isoprenaline, followed by a single high concentration of forskolin and calcium. Beta-AR sensitivity was estimated as the concentration to achieve half maximum effects (EC50). Maximum effect size was calculated as the relative beta-AR-mediated inotropic response compared to the force in the presence of high calcium [FISO/Ca (%)]. In vitro data were correlated with the clinical indicators of LV disease.

RESULTS

FISO/Ca was independent of age and sex and amounted to 79.6 ± 20.5%. In a multivariate regression model, we found a significant inverse association between FISO/Ca and preoperative left ventricular end-diastolic diameter increase per 10 mm (OR −9.24, 95% CI −16.66 to −1.82; P = 0.015). Furthermore, patients with end-stage heart failure showed a strong tendency towards more severe reduction of max beta-AR response, as indicated by reduced FISO/Ca in a multivariate model (OR −29.60, 95% CI −61.92 to 2.72; P = 0.055).

CONCLUSIONS

Our study indicates that in vitro myocardial contractility testing can quantify beta-AR dysfunction in patients with AV disease. We found a significant association between reduced beta-AR sensitivity and increased LV diameter, which may indicate a role of beta-AR dysfunction in the development of heart failure in patients with AV disease.
RECOMBINATION AND TRANSFECTION MAPPING OF CISTRON 5 OF BACTERIOPHAGE SP82G
Authors: Green D MacDonald , Urban Margeret I
Published: January 2021

Recombination between transfecting SP82G DNA molecules has been studied in Bacillus subtilis. Recombinant progeny issuing from transfected cells show many of the features that characterize progeny production in multiplicity reactivated bacteriophage, such as: majority recombinant clones, non-reciprocity of recombinant clones and the frequent absence of input alleles. While transfection substantially lowers the linkage observed between markers in normal phage crosses, linkage is observed at small map distances in transfection either by plating transfected bacteria or the progeny phage. Maps constructed from transfection crosses are identical to those of normal phage crosses, except in magnitude.—Examination of the concentration response of two marker biparental crosses, and three marker triparental crosses using transfecting DNA leads to the conclusion that at all concentrations, transfective centers are saturated with respect to the number of molecules that can be taken up. Thus, the frequency of recombinant infective centers, or recombinant progeny is independent of concentration effects.
INTERACTIONS BETWEEN COLICINOGENIC FACTOR B AND F-TYPE FACTORS: ISOLATION OF A MUTANT F-lac FACTOR INSENSITIVE TO THE EFFECT OF COLICINOGENIC FACTOR B
Authors: Negrotti T , de Zwaig R Nagel
Published: January 2021

An extrachromosomal factor, colicinogenic factor B (colB) inhibits expression of fertility functions of various F-type factors in strains of E. coli K12. Mutant F-lac factors simultaneously became insensitive to all the effects of colB as well as to similar actions exerted by a resistance transfer factor, R fi+. This suggests that a common site or activity necessary for the expression of several F functions is affected by products of both colB and R fi+.
PROPERTIES OF TWO NUCLEASE GENES IN NEUROSPORA CRASSA
Authors: Hasunuma Kohji , Ishikawa Tatsuo
Published: January 2021

Two genes, nuc-1 and nuc-2, of Neurospora crassa which were responsible for the nucleic acid digestion, were located on linkage group 1 and 2, respectively. A temperature-sensitive mutant (B1ts-2) was obtained from a nuc-2 mutant. Nuclease mutants showed a reduced activity of nuclease N3 which was found to be a complex consisting of nuclease N3' and inhibitor molecule. Nuclease N3, nuclease N3' and inhibitor were partially purified and estimated to have the approximate molecular weights of 38,000, 12,500 and 25,000 respectively. A nuc-1 mutant produced the nuclease N3' altered in thermolability. A nuc-2 mutant and B1ts-2 produced the inhibitor altered in the capacity to inhibit nuclease N3' activity. The inhibitor prepared from B1ts-2 was more thermostable than that from other strains. From these results, it was suggested that the nuc-1 gene is the structural gene for nuclease N3' and the nuc-2 gene that for the inhibitor. A possible involvement of this enzyme-inhibitor complex in the regulation of nuclease activity and synthesis of other proteins was suggested.
THE EFFECTS OF HETEROZYGOSITY CHANGES ON VIABILITY IN DROSOPHILA MELANOGASTER
Authors: Moree Ray
Published: January 2021

The viability effects of chromosomes from an old and from a new laboratory strain of D. melanogaster were studied in eight factorial combinations and at two heterozygosity levels. The combinations were so constructed that heterozygosity level could be varied in the third chromosomes of the carriers of a homozygous lethal marker, in the third chromosomes of their wild-type segregants, and in the genetic backgrounds of both. Excluding the effect of the marker and the exceptional outcomes of two of the combinations, and taking into account both large and small deviations from theoretical expectation, the following summary is given as the simplest consistent explanation of the results: 1) If total heterozygosities of two segregant types tend toward equality their viabilities tend toward equality also, whether background heterozygosity is high or low; if background heterozygosities is higher the tendency toward equality is slightly greater. 2) If total heterozygosity of two segregant types are unequal the less heterozygous type has the lower viability; the difference is more pronounced when background heterozygosity is low, less when it is high. 3) Differences between segregant viabilities are correlated with differences between the total heterozygosities of the two segregants; genetic background is effective to the extent, and only to the extent, that it contributes to the magnitude of this difference. This in turn appears to underlie, at least partly, the expression of a pronounced interchromosomal epistasis. Thus in this study viability is seen to depend upon both the quantity and distribution of heterozygosity, not only among the chromosomes of an individual but among the individuals of a given combination as well.
GENETIC FINE STRUCTURE ANALYSIS OF THE AMYLOSE-EXTENDER LOCUS IN ZEA MAYS L
Authors: Moore Carol W , Creech Roy G
Published: January 2021

On the basis of interallelic recombination frequencies measured in diallelic crosses of the 5 amylose-extender alleles in maize, ae, B1, B3, M2 and i1, it was possible to construct a unique linear genetic map ordering all 5 alleles within the locus. The reciprocal diallelic crosses each gave comparable frequency estimates. The relative order is ae, i1, B3, B1, M2 or the reverse. Even though F1 endosperms resulting from all possible diallelic crosses were phenotypically mutant, therefore non-complementing, no decision as to whether or not these alleles exhibit functional complementation should be made without biochemical characterization of the starches from the various heteroallelic genotypes.
A MESSENGER RNA FROM THE LACTOSE OPERON OF ESCHERICHIA COLI THAT CAN NOT DIRECT THE PRODUCTION OF FUNCTIONAL β-GALACTOSIDASE IN ABSENCE OF EXOGENOUS ADENOSINE 3',5'-CYCLIC MONOPHOSPHATE
Authors: Simon Michel , Apirion David
Published: January 2021

In a temperature-sensitive mutant of Escherichia coli, β-galactosidase cannot be induced at the nonpermissive temperature (43°C) without the addition of exogenous 3´, 5´-cyclic AMP (cAMP), although the intracellular concentration of this nucleotide is normal. This specific effect of cAMP is probably general in this strain for those operons which are controlled by the cAMP receptor protein and cAMP, but not for other parts of the chromosome. The lac mRNA produced at 43°C in absence of cAMP is transcribed from the correct DNA strand and it directs the synthesis of enzymatically inactive material cross-reacting with β-galactosidase. Experiments separating transcription from translation by using rifampicin, suggest that cAMP exerts its effect during initiation of transcription or translation of lac mRNA, but does not affect the propagation of either the messenger or of the β-galactosidase polypeptide chain.
DOMINANCE MODIFIERS IN NEUROSPORA CRASSA: PHENOCOPY SELECTION AND INFLUENCE ON CERTAIN ASCUS MUTANTS
Authors: Russell Peter J , Srb Adrian M
Published: January 2021

When homozygous in zygotes, mutant alleles at the peak locus in linkage group V of Neurospora crassa initiate aberrant asci that are nonlinear, in contrast to the linear asci characteristic of wild type. Most mutant alleles are recessive, inasmuch as crosses of the mutant strains with wild type give linear asci. However, five different mutant alleles, when heterozygous with the wild-type allele, act in varying degrees as zygote dominants, initiating both linear and nonlinear asci, the relative proportions depending on the allele. Five modifiers that act on the dominance relationships of at least one of the five possible heterozygotes of a dominant peak and its wild-type allele have been characterized, four of them having been obtained by selection directed against a phenocopy of these mutants induced by treatment of wild type with l-sorbose. The pattern of modifier specificity observed among the various dominant peak heterozygotes indicates that the phenotypic effects are produced by a complex relationship between the modifiers and the dominant peak alleles in relation to their wild-type allele. In all but two cases the direction of modification, where present, is towards decreasing the dominance of the mutant allele in the heterozygote, evidenced by an increase in the percentage of linear asci when compared with control data. The modifiers exert their maximum modification when they themselves are heterozygous with their wild-type alleles and when the dominant peak allele is heterozygous with its wild-type allele. No modification occurs when heterozygous modifiers are included in zygotes homozygous for a dominant peak allele, reinforcing the notion that the modifiers act on the dominance relationship existent between a dominant peak allele and its wild-type allele, rather than influencing some activity of the mutant allele itself. The modifiers have no detectable effect of their own on ascus morphology, since homozygous modifier zygotes initiate entirely linear asci when only wild-type alleles of peak are present in the zygotes. Their only detectable effect, other than dominance modification, appears to be in conferring sorbose resistance to the mycelium. The modifiers are unlinked to the peak locus, and, except for two of them, they are nonallelic.
INHERITANCE OF ESTERASES A AND B IN SYNGEN 2 OF PARAMECIUM AURELIA
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Authors: Allen Sally Lyman , Golembiewski Patricia A
Published: January 2021

Stocks 50, 93 and 305 in syngen 2 of Paramecium aurelia differ in their A esterases. Stock 305 also has a variant B esterase. The results of crosses carried out between stocks show that the A and B esterases are under the control of separate genes, thus confirming the prediction based on differences in the chemical properties and the distribution of these esterases in different syngens.
ISOLATION AND CLASSIFICATION OF EXTRANUCLEAR MUTANTS OF NEUROSPORA CRASSA
Authors: Bertrand H , Pittenger T H
Published: January 2021

Four extranuclear mutants, [exn-1], [exn-2],[exn-4], and [stp-C], were obtained from N-methyl-N'-nitro-N-nitrosoguanidine-treated conidia and mycelium of Neurospora crassa. The three exn mutants grow with a pronounced lag from conidia and ascospores and are female fertile, whereas [stp-C] has a stop-start growth phenotype and is female sterile. The mitochondria from all four mutants are deficient in cytochromes a+a  3 and b, but contain an excess of cytochrome c. On the basis of growth and fertility, nuclear suppressors and complementation in heteroplasmons, 16 of the extranuclear mutants now available in Neurospora can be divided into three groups. Group I consists of 8 female-fertile variants with both poky-like growth and cytochrome defects. Their slow growth is suppressed by the nuclear factor, f, but not by a second nuclear suppressor, su-1([mi-3]). They complement with group III mutants in mixed cytoplasmons. Group II is represented by a single variant, [mi-3]. It is phenotypically modified by the su-1([mi-3]) factor, but not by f. Its unique cytochrome spectrum shows a deficiency of cytochrome a, but c and b are present. It complements in heteroplasmons with group I and III mutants. Group III included 7 female-sterile variants with stopper growth phenotypes and the same cytochrome defects as group I. Group III mutants complement both with group I and II isolates, but they are unaffected by either f or su-1.
SEGREGATION OF TWO ALLELES FOR COLOR OF DOWN IN PARTHENOGENETIC AND NORMAL TURKEY EMBRYOS AND POULTS
Authors: Olsen M W , Buss E G
Published: January 2021

Data were collected on the down color of 1,386 parthenogenetic embryos and poults from eggs of 306 young virgin and older nonmated bronze turkey hens. Each hen involved was heterozygous (Cc) for alleles which affect feather pigmentation. Six hundred and sixty nine white and 717 colored parthenogenetic embryos and poults were observed, a 1:1 ratio. Subsequently, 89 of these 306 heterozygous bronze hens were inseminated with semen from BSW (cc) males and down color of embryos and poults from fertilized eggs recorded. the 89 females produced a total of 233 white and 239 colored normal embryos and poults. The 1:1 ratio for down color among both parthenogenetic and normal embryos and poults shows that, in both instances, the two alleles at a locus on an autosome segregated equally. Four possible cytological routes which would lead to diploidy were discussed.
8-AZAGUANINE RESISTANCE IN MAMMALIAN CELLS I. HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE
Authors: Gillin F D , Roufa D J , Beaudet A L , Caskey C T
Published: January 2021

Chinese hamster cells were treated with ethyl methanesulfonate or N-methyl-N'-nitro-N-nitrosoguanidine, and mutants resistant to 8-azaguanine were selected and characterized. Hypoxanthine-guanine phosphoribosyltransferase activity of sixteen mutants is extremely negative, making them suitable for reversion to HGPRTase+. Ten of the extremely negative mutants revert at a frequency higher than 10-7 suggesting their point mutational character. The remaining mutants have demonstrable HGPRTase activity and are not useful for reversion analysis. Five of these mutants have < 2% HGPRTase and are presumably also HGPRTase point mutants. The remaining 14 mutants utilize exogenous hypoxanthine for nucleic acid synthesis poorly, and possess 20-150% of wild-type HGPRTase activity in in vitro. Their mechanism of 8-azaguanine resistance is not yet defined.
REGULATION OF RIBOSOMAL RNA AND 5s RNA SYNTHESIS IN DROSOPHILA MELANOGASTER: I. BOBBED MUTANTS
Authors: Weinmann Roberto
Published: January 2021

Analysis of the rates and amounts of rRNA and 5s RNA synthesized in Drosophila melanogaster bobbed mutants was done by using acrylamide-gel electrophoresis. The results show that the amounts of rRNA synthesized are constant, although the rates of rRNA synthesis in bb's are reduced to 30% of the wild-type level. The rates of synthesis of 5s RNA were constant. The rate of synthesis of the two kinds of molecules that enter in equimolar amounts into the mature ribosome is non-coordinated.—The rates of rRNA synthesis were shown to be proportional to the length of the scutellar bristles, supporting the notion that in trichogen cells there is no developmental delay, but the size of the bristle depends directly on the rate of rRNA synthesis.
SYNERGISTIC EFFECT OF INBREEDING ON VIABILITY IN DROSOPHILA VIRILIS
Authors: Kosuda Kazuhiko
Published: January 2021

The effect of inbreeding on egg to adult viability was determined for Drosophila virilis over a wide range of inbreeding levels (0 < F <.734). The quantity —loge (Viability) was found to be a curvilinear function of F, indicating synergistic interaction among loci. The curvature was not evident, however, below F =.500. The values of A and B (Morton et al. 1956) were calculated to be.06 and.77-.86, respectively. This extremely small value of A yielded a very large value for the B/A ratio i.e., 12.51-14.99.
ELECTROPHORETIC MUTANTS AS USEFUL MARKERS FOR CHROMOSOME ABERRATIONS
Authors: Kleese R A , Phillips R L
Published: January 2021

The efficacy of using an electrophoretic mutant to mark chromosome aberrations was demonstrated for an interchange in maize. Using a closely-linked esterase gene (E  4), plants homozygous and heterozygous for this interchange and plants homozygous for the normal chromosomes were detectable in the seedling stage via an electrophoretic assay; the error was only 0.3%.
SELECTIVE ALLELE LOSS IN MIXED INFECTIONS WITH T4 BACTERIOPHAGE
Authors: Benz Wendy C , Berger Hillard
Published: January 2021

Evidence is presented that when E. coli B is mixedly infected with T4D wild type and rII deletion mutants, the excess DNA of the wild type allele is lost. No loss is seen in mixed infections with rII point mutants and wild type. In similar experiments with lysozyme addition mutants, the mutant allele is lost. We believe these results demonstrate a repair system which removes "loops" in heteroduplex DNA molecules. A number of phage and host functions have been tested for involvement in the repair of the excess DNA, and T4 genes x and v have been implicated in this process.
THE INABILITY OF YEAST TRANSFER RNA TO SUPPRESS AN AMBER MUTATION IN AN E. coli SYSTEM
Authors: Kiger John A , Brantner Carol J
Published: January 2021

Transfer RNA from super-suppressor mutants of Saccharomyces cerevisiae cannot suppress an amber mutation in vitro in an E. coli protein synthesizing system. It is tentatively concluded that the yeast amber suppressor does not contain a transfer RNA altered in the anticodon.
GENETIC RECOMBINATION IN COPRINUS. IV. A KINETIC STUDY OF THE TEMPERATURE EFFECT ON RECOMBINATION FREQUENCY
Authors: Lu B C
Published: January 2021

At the restrictive conditions (35° under continuous light) Coprinus lagopus is unable to initiate premeiotic S phase which takes place normally within 8-10 h of karyogamy. A shift-up to the restrictive conditions causes an arrest of the basidiocarps at this critical stage. A prolonged arrest causes a reversal to mitosis (Lu 1974b). Incubation of basidiocarps at the restrictive conditions before this critical stage causes no increase in recombination frequency (R.F.) in the loci studied. An arrest of 4 h at the critical stage still causes no R.F. increase, but 12-13 h and 18-19 h arrests cause increases of 50% and 90% over the controls, respectively. Thus R.F. can be increased even before the cells are fully committed to meiosis.—A 3-h heat treatment at the beginning of S phase (or 8 h before karyogamy) also causes some (30%) increase in R.F. while the same treatment at late S phase (or 3 h before karyogamy) causes a substantial (164%) increase in R.F. over the controls. A 3-h heat treatment before S phase causes no increase in R.F.—Pachytene is also responsive to temperature treatments (Lu 1969). The maximum R.f. increase is 100% by heat and 220% by cold treatment. The shortest time that can cause the maximum increase in recombination by high temperature is 3 h and that by cold treatment is 7 h. These durations are correlated with the length of the pachytene stage under the treatment conditions. The kinetic data show that the increase in R.F. caused by high and low temperatures follows two-hit kinetics and their rate of increase is almost identical. The higher increase in R.F. by low temperature can be attributed to the increased duration of pachytene and therefore R.F. is a function of time. The longer the homologous chromosomes are held together, the higher the recombination frequency.