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WAAM technology (Wire + Arc Additive Manufacture) is a new method of additive manufacturing using wire as a construction material. The high productivity of the process, the ability to construct large-sized products without the need to use a controlled atmosphere chamber, and the low cost of equipment and construction materials allow using the WAAM technology to built products of simple and medium complexity with the highest economic efficiency. However, WAAM technologies in MIG-Pulse/CMT surfacing processes have a number of disadvantages, such as significant size of the heat-affected zone (HAZ) and large sizes of the build-up layer, which leads to undesirable temperature gradients and the accumulation of residual stresses. A further way to improve WAAM technology is to use metal-cored wires. For the research, metal-cored wire Cr20Mn5Ni4Mo2.5Cu3N0.3 Ø 1.6 mm was developed. It has been established that the use of metal-cored wire allows producing a defect-free surfaced metal with an austenite-ferritic structure (δF ≈ 1–3%), which has high strength and plastic characteristics (σB = 810 MPa, σ0,2 = 500 MPa, δ = 40%). The yield strength of the developed composition is more than 2 times higher than that of the widespread austenitic steel of the Kh18N10T type (σ0,2 = 206 MPa). Further research will be aimed at improving the impact strength of the surfaced cast metal by optimizing the composition of the metal-cored wire. [ABSTRACT FROM AUTHOR]

An austenitic metal-cored wire (diameter – 1.6 mm) with additional nitrogen alloying (0.25–0.40 wt.%) was developed for this study. Mechanical tests and metallographic studies of the deposited metal and welded joints made with austenitic metal-cored wire (composition – Cr20Mn5Ni4Mo2.5Cu3N0.3) were conducted. It was found that the values of σu and σ0.2 of the deposited metal obtained by using the developed wire were 20 to 30% higher compared to the utilized electrode materials, while the ductility characteristics were preserved (δ = 43%). It was shown that the use of metal-cored wire (Cr20Mn5Ni4Mo2.5Cu3N0.3) for welding of high-strength steel 20HGSNM (EN 1.6523) makes it possible to obtain defect-free welded joints with austenitic-ferritic structure, which have 20% higher strength characteristics compared to the analogues. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the impact of Boston Type I Keratoprosthesis (BI-Kpro) implantation on retinal and visual pathway function, respectively, assessed by full-field electroretinography (ERG) and visually evoked potentials (VEPs). Methods : This is a prospective interventional longitudinal study, and patients with BI-Kpro implantation were assessed preoperatively and at 3 and 12 months after surgery. ERG, flash, and pattern-reversal VEPs (15' and 60' checks) along with visual acuity (VA) were performed. Results: A total of 13 patients (24 to 88 years of age) were included. Mean baseline VA (logMAR) improved from 2.30 to 1.04 at 3 months and to 1.00 at 12 months. Flash VEPs were normal in 6 (46%) patients and in 10 (77%) patients at the 12-month follow-up. PVEP was non-detectable in all patients preoperatively for both check sizes. For 15' check size, 6 (46%) patients showed responses after 3 and 12 months except for 1 patient with normal responses at 12 months with the remaining non-detectable. For 60' checks, 11 (85%) patients had responses 3 months after surgery with only 9 (70%) showing responses at 12 months. Abnormal full-field ERGs were found in all patients preoperatively. Amplitude improvement was found in 10 (77%) patients from baseline to 3 months and in 8 (62%) patients from the 3- to the 12-month follow-up. Conclusions: In this small cohort of patients with BI-Kpro implantation, a remarkable improvement on visual function quantitatively assessed by electrophysiological testing was found in the majority of cases. Visual electrophysiological testing can contribute to objectively assess functional outcomes in this population. [ABSTRACT FROM AUTHOR]

We tackle here genomic mechanisms of a rapid onset and recovery from anosmia—a potential diagnostic indicator for early-stage COVID-19 infection. Based on previous observations on how olfactory receptor (OR) gene expression is regulated via chromatin structure in mice, we hypothesized that the disruption of the OR gene expression and, respectively, deficiency of the OR function can be caused by chromatin reorganization taking place upon SARS-CoV-2 infection. We obtained chromatin ensemble reconstructions from COVID-19 patients and control samples using our original computational framework for the whole-genome 3D chromatin ensemble reconstruction. Specifically, we used megabase-scale structural units and effective interactions between them obtained in the Markov State modelling of the Hi-C contact network as an unput in the stochastic embedding procedure of the whole-genome 3D chromatin ensemble reconstruction. We have also developed here a new procedure for analyzing fine structural hierarchy with (sub)TAD-size units in local chromatin regions, which we apply here to parts of chromosomes containing OR genes and corresponding regulatory elements. We observed structural modifications in COVID-19 patients on different levels of chromatin organization, from the alteration of whole genome structure and chromosomal intermingling to reorganization of contacts between chromatin loops at the level of topologically associating domains. While complementary data on known regulatory elements point to potential pathology-associated changes within the overall picture of chromatin alterations, further investigation using additional epigenetic factors mapped on 3D reconstructions with improved resolution will be required for better understanding of anosmia caused by SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the diagnostic contribution of grating visual acuity (GVA) measured by sweep pattern-reversal visually evoked potentials (SPRVEP) in unexplained visual loss (UVL). Methods: This case-control study included adult patients under suspicion of UVL referred to SPRVEP and transient pattern-reversal visually evoked potentials (TPRVEP) testing. Optotype visual acuity (OVA) was measured by ETDRS 4-meter chart and GVA by SPRVEP. UVL patients were assigned into three distinctive categories, according to the presence of ocular disease, motivation, and electrophysiological evaluation, as follows: exaggerators, malingerers, and psychogenic. Healthy controls and patients with organic visual loss were also tested. Receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic performance of GVA and TPRVEP parameters. Results: A total of 76 patients with UVL were analyzed: 60 (79.0%) exaggerators, 11 (14.4%) malingerers, and 5 (6.6%) psychogenic. Controls were 49 subjects evaluated for TPRVEP and 28 subjects for SPRVEP. There were 13 patients with organic visual loss enrolled. Mean difference between OVA and GVA was 1.19±0.67 (median=0.84; 95% CI: 1.04 to 1.34) in UVL and 0.14 ±0.09 (median= 0.14; 95% CI: 0.08 to 0.20) in organic visual loss. The area under the ROC curve (AUC) of GVA to distinguish UVL from healthy controls was 0.998 with a cutoff of 0.09 logMAR showing specificity of 100% and sensitivity of 96.0%. Conclusions: GVA measured by SPRVEP had good diagnostic validity to discriminate patients with unexplained visual loss from healthy controls and patients with organic visual loss, demonstrating its contribution to the diagnosis of this condition. [ABSTRACT FROM AUTHOR]

A new bivalve species C. (Crassatella) lassa is described from the Upper Eocene sediments of the village of Luzanivka (Cherkasy Region, Ukraine). It occurred together with valves of 15 bivalve species including Crassatella personata Berezovsky, Crassatina woodi (Koenen), Miocardiopsis praelonga (Giebel), Tivelina deleta (Koenen), Pitar porrecta (Koenen), Circe edwardsi (Koenen), Barbatia rustica (Koenen), and Spondylus tenuispina Sandberger. These species are exclusively found in Upper Eocene sediments, thus indicating a Late Eocene age for sediments with C. lassa. [ABSTRACT FROM AUTHOR]

The results of the revision of Crassatella (Bathytormus) species from Middle Eocene deposits exposed by the quarry of the Ingulets Mining and Processing Plant and Vizirka-1 quarry (town of Krivoi Rog) are presented. The genus Bathytormus has been reclassified as a subgenus. Forms with ridge-like ribs in the umbonal region were differentiated from the species previously described as Bathytormus cipitis cipitis (Berezovsky, 1998) and described as a new species, Crassatella(Bathytormus)ignava sp. nov. The name C. (B.) cipita is retained for valves in which the upper part is covered with spaced lamellar ribs. C. (B.) cipita and its nominotypical subspecies are redescribed due to changes in their composition and diagnostic features. [ABSTRACT FROM AUTHOR]

Recently, it has been recommended that population-based studies report not only frequencies of vision impairment and blindness but also any ocular abnormalities that might lead an individual to seek for eyecare services. The current study aimed to determine prevalence of ocular findings regardless of visual acuity (VA) status in older adults from the Brazilian Amazon Region. Disturbances were grouped into: Eyelids; Anterior Segment; Posterior Segment; Increased intraocular pressure; and Overall Globe. The presence of an ocular finding was considered positive when any abnormality was noted, regardless of VA. Refractive errors were not considered. A total 2384 eligible persons were enumerated and 2041 (85.6%) examined. The prevalence of ocular disturbances in either eye was 87.0% and was associated with male gender, older age, lower education, and rural residence. Overall, main findings were pterygium, cataract, and pinguecula, occurring in 58.8%, 45.4% and 17.4%, respectively. Among individuals with 20/20 VA in both eyes, the most frequent findings were pterygium, pinguecula, and glaucoma cupping, occurring in 47.4%, 31.2% and 6.5%, respectively. The high prevalence of ocular findings observed in this population reinforces that different conditions might not immediately decrease VA but can indicate risk and/or discomfort symptoms and should be considered when planning public health ophthalmic services. [ABSTRACT FROM AUTHOR]

Two new bivalve species of the genus Chama, C. subcalcarata and C. ferrata, from the Middle Eocene of Krivoi Rog are described. [ABSTRACT FROM AUTHOR]

It is often impossible or impractical to conduct experiments on cooling, freezing, and thawing during medical cryoexposures with using biological tissues. In such cases, gel-phantoms are used. Due to the lack of accurate data, the definition of the thermal properties of gel-phantoms is relevant. The current study presents the results of the thermal properties measurements with using the differential scanning calorimetry (DSC) and transient hot bridge (THB) methods and of their analysis for five gel-phantoms: 1) 95% water and 5% gelatin; 2) 95% water and 5% agar-agar; 3) 94% water, 3% gelatin, 2.5% agar-agar, and 0.5% sodium chloride; 4 and 5) ultrasound gels. The values of the effective specific heat capacity from –160 to 40°C, thermal conductivity, moisture content, freezable water fraction, and of the initial melting and cryoscopic temperatures are determined. The obtained results are compared with the values of the thermal properties of biotissue and distilled water. The influence of the gelphantom type on the character of phase transition is shown. Adaptation of the experimental data for cryoexposure simulation software is proposed. Recommendations for selecting a phantom are given. The impact of simplification of the thermal properties on the thermal diffusivity is estimated. The data for calculating the properties of phantoms of different composition are proposed. [ABSTRACT FROM AUTHOR]

The species Chama clavaticostata Klushnikov, 1958, which was originally described based on one juvenile exemplar from the Middle Eocene in the environs of the town of Krivoi Rog (Ukraine), is redescribed. [ABSTRACT FROM AUTHOR]

Purpose: To determine normative values, intra- and inter-session variability for a range of parameters derived from the photopic negative response (PhNR) using a handheld mini-Ganzfeld stimulator in healthy normal adults. Methods: Light-adapted flash full-field electroretinograms (ERGs) were recorded from healthy individuals with no visual complaints, visual acuity equal to or better than 0.0 logMAR (20/20 Snellen), and negative family history for visual diseases. ERGs were recorded from both eyes using a DTL® type fiber electrode after dilation of the pupils with instillation of 1 drop of tropicamide eye drops (1%). The full-field PhNR stimulus conditions were produced by a LED-based ColorBurst™ (Diagnosys LLC, Lowell, MA, USA) handheld stimulator. Red flashes of 1, 5 and 7 cd.s/m2 on a blue background of 10 cd/m2 were presented. A-wave, b-wave and PhNR amplitude (determined by both baseline to trough-BT and peak to trough-PT) and peak times were analyzed. Normal limits were determined as 5% percentile for amplitudes and 95% percentile for latencies. Intra- and inter-session variability were assessed with Wilcoxon signed-rank test, intraclass correlation coefficient (ICC) and the coefficient of variability (COV). Results: Normative limits for PhNR amplitude (µV) using 1, 5 and 7 cd.s./m2 stimuli were, respectively: 20.81; 18.06 and 19.60 for BT and 69.11; 77.98; 76.51 for PT. Peak times (ms) normative limits for 1, 5 and 7 cd.s/m2 intensities were, respectively, 65.98; 78.20 and 77.96. Overall, intra-session variability assessed by coefficients of variation ranged from 1.35 to 10.28%. Inter-session variability disclosed significant intraclass correlation values for all PhNR parameters only for 1 cd.s/m2 stimuli. Conclusions: The normative values provided by this study are clinically helpful in the diagnosis of inner retinal disorders, especially those affecting retinal ganglion cells such as glaucoma and other optic neuropathies. Further studies, including a larger sample with variable age range would extend the validity of the current results. [ABSTRACT FROM AUTHOR]

Three new species of bivalves of the family Cardiidae are described from the Paleogene of Ukraine: Freneixicardia picturata (Upper Eocene, town of Dnepr), Loxocardiummarmoreum (Middle Eocene, the town of Kanev), and Schedocardia imperfecta (Middle Eocene, town of Ingulets). The species Loxocardium denticostatum (Berezovsky, 1998) is redescribed, because its first description was based on specimens (besides the types), which are assigned in this work to the new species L. marmoreum. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of a child with strabismus and delayed discovery of a metallic intraocular foreign body with good recovery of visual acuity and stereopsis with 36-month follow-up. Methods: A 4-year-old girl was evaluated due to exotropia of right eye initiated 9 months before with progressive worsening. Visual acuity was 1.00 logMAR (20/200) in the right eye and 0.00 logMAR (20/20) in the left eye. Anterior segment evidenced a small paracentral corneal leukoma, posterior synechia and mild lens opacity in the temporal quadrant only in the right eye. Fundus examination in the right eye identified the presence of an intraocular foreign body, with appearance of metallic components surrounded by retinal pigmented endothelial cells atrophy. Full-field electroretinography (ERG) showed reduced amplitudes and delayed implicit times for both rods and cones in the affected eye. All tests were normal in the fellow eye. Results: Pars plana vitrectomy was promptly performed in the right eye, followed by phacoemulsification with intraocular lens implantation 4 months later due to worsening of the lens opacification. The full-field ERG was repeated after the surgical procedures. The ERG showed mild worsening of all responses in the right eye. After 36 months of follow-up, visual acuity was 0.20 logMAR (20/32) with improvement of the ocular misalignment and with 60 s of arc stereopsis with ERG responses unchanged. Conclusion: In this young girl perforating ocular trauma with metallic material was lately diagnosed with strabismus as a sign of alert. Prompt surgical intervention and proper management were essential to provide reasonable visual function including some degree of stereopsis, even though retinal dysfunction characterized by ERG was persistent. [ABSTRACT FROM AUTHOR]

new species of the genus Chelotia, C. pervicina sp. nov., from Middle Eocene deposits of the southern outskirts of the town of Krivoi Rog (Ukraine) is described. This species is compared with the most similar species C. concava (Deshayes) based on studying Chelotia specimens from the collection of the National Museum of Natural History (Paris, France). [ABSTRACT FROM AUTHOR]

Abstract: In the second part of the monograph, bivalves of the family Crassatellidae from the Upper Eocene Mandrikovka Beds of Dnepr (former city of Dnepropetrovsk, Ukraine) and its environs are described. The family Crassatellidae is represented by 25 species, 21 of which were established by the author. These species belong to the genera Crassatella (Crassatella) (seven species), Crassatella (Furvusa subgen. nov.) (one species), Crassatella (Bathytormus) (five species), Crassatina (Crassatina) (four species), Crassovella gen. nov. (four species), and Chattonia (three species). All of these taxa are described and provided with figures of type species. Species are figured in 15 plates. These taxa are mostly established on the shell material from the Upper Eocene beds exposed by the Rybalsky quarry in the city of Dnepr. Valves belonging to the new genus Crassovella and new subgenus Crassatella (Furvusa) come from the same beds. Three out of 25 species are described from a core of the same age, which was obtained during drilling in the vicinity of Dnepr (near the towns of Sinel'nikovo and Kamensky and the village of Vasil'kovka). [ABSTRACT FROM AUTHOR]

Abstract: Three new species of Crassatellidae: Crassatella ballista sp. nov., C. calva sp. nov., and Eucrassatella depulsoris sp. nov. from the Middle Eocene deposits of the western slope of the a quarry of the Ingulets Ore Mining and Processing Enterprise (Ingulets, Ukraine), which are correlated with the Lutetian Stage, are described. The study of valves of Crassatella parisiensis Orbigny, 1852 from the Middle Eocene deposits of the Parisian Basin has shown that it differs from the species C. illustris Berezovsky, 2004, which was previously described as a subspecies of C. parisiensis. The study of variation of Crassatellidae provided substantiation of the species rank of C. artacosta Berezovsky, 2004, which was previously described as a subspecies of C. densicostata Berezovsky, 1998. [ABSTRACT FROM AUTHOR]

Representatives of the genus Crassatina from the Upper Eocene Mandrikovka Beds in the vicinity of Dnepr (former Dnepropetrovsk) are discussed and figured. From the Mandrikovka assemblage, two new species, C. conquisita and C. insolita, are described. One more new species, C. subcostata, is described from the Middle Eocene deposits of southern suburbs of Krivoi Rog. Two species, C. raricostata (Klushnikov) and C. expolita (Klushnikov), which were originally established as varieties, are redescribed and their species rank is substantiated. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the contribution of full-field transient pattern-reversal visually evoked potentials (PRVEP) on cross-sectional evaluations of visual function in patients with and without neurofibromatosis type 1 (NF1) affected by optic pathway low-grade gliomas (OPLGG).Methods: Participants were children and adolescents referred for visual function evaluation and receiving treatment for OPLGG, linked (NF1-OPLGG) or not to NF1 (Non-NF1-OPLGG). An age-adjusted control group was included for comparison. Monocular full-field PRVEPs were recorded from each eye in accordance with ISCEV standards. Parameters of peak-to-peak P100 amplitude (µV) and P100 peak time (ms) were measured. Cutoff normative values obtained from controls for 15′ and 60′ check sizes were ≥ 9.0 µV for N75-P100 amplitude and ≤ 103.0 ms for P100 peak time. The association of age, gender, tumor resection and NF1 with P100 amplitude reduction and P100 peak time delay was explored by Firth logistic regression modeling.Results: Participants were 30 patients (15 males, 60% Non-NF1) with ages from 3.6 to 19.9 years (mean ± SD = 9.2 ± 3.8 years; median = 8.4 years) and 19 controls (12 males) with ages from 3.7 to 19.9 years (mean ± SD = 10.4 ± 4.9 years; median = 9.5 years). Overall, 68% of tested eyes presented reduced P100 amplitudes for both check sizes (46% in the NF-1 and 83% in the Non-NF1) and delayed P100 for both check sizes (38% in NF1 and 89% in Non-NF1). Absence of NF1 adjusted for age, gender and tumor resection was significantly associated with marginally reduced P100 amplitude for 15′ checks [odds ratio (OR): 6.26; 95% confidence interval (CI) = 0.96-40.94; p = 0.055].Conclusions: Full-field PRVEP on cross-sectional evaluations contributed to detect visual dysfunction in two-thirds of patients with OPLGG by highlighting subclinical evidence of visual loss. Abnormalities were more frequent and more severe in OPLGG not linked to NF1 than in NF1-OPLGG; however, there was a difference in surgical management between these groups. PRVEP parameters may provide reliable evidence of visual pathway involvement in OPLGG, helping to hasten treatment before optic atrophy is detected. [ABSTRACT FROM AUTHOR]

Molecular simulations have been employed to explore at the microscopic scale the adsorption of CO in zeolites (MFI, CHA and DDR). On the basis of classical force fields, grand canonical Monte Carlo simulations are performed to predict the adsorption properties (isotherms) of these types of zeolites up to high pressure. Subsequent careful analysis yields details the microscopic mechanism in play, along the whole adsorption process, together with a considering of the arrangements of CO in MFI at high pressure. This work also summarizes an approach which uses single component diffusion data in prediction of multicomponent diffusion. [ABSTRACT FROM AUTHOR]

A differential scanning calorimetry study of the specific isobaric heat capacity, phase-transition enthalpy, moisture content, and cryoscopic temperature for samples of benign and malignant human prostate tumor tissues is reported. Empirical relationships have been obtained that describe the specific isobaric heat capacity of prostate-tissue samples in a wide temperature range and the effect of the moisture contents of the samples on the cryoscopic temperature and the heat of the phase transition, as well as a semi-empirical relationship that describes the effective specific-heat capacity in the subcryoscopic temperature range. The correlations and experimental data presented in this article can be used in mathematical modeling and optimization of heat-exchange processes in cryosurgery. [ABSTRACT FROM AUTHOR]

Background: Desmoid tumors are borderline tumors of the connective tissue, arising in the musculo-aponeurotic stromal elements. A desmoid tumor (DT) has an infiltrative and locally aggressive growth pattern and usually does not metastasize; however, it has a high recurrence and complication rate. DT located in the breast (BDT) represents a rare extra-abdominal form. Recently, the presence of breast silicone implants was suggested by several researchers as a risk factor for developing BDT. Objectives: The goal of this review is to investigate the possible correlation between BDT and breast implant surgery. Methods: We conducted a literature review of BDT-reported cases, associated with breast implant surgery. Results: The search revealed 36 cases of BDT associated with silicone breast implants. Conclusions: Based on the reviewed data, the incidence of BDT following breast implant surgery is lower than BDT in the general population. At the moment, a possible association between breast implants and the development of breast desmoid tumors cannot be unequivocally confirmed. A world registry with accurate documentation of each case of BDT associated with breast implant surgery should be performed for future investigation. Level of Evidence II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors . [ABSTRACT FROM AUTHOR]

Three new bivalve species of Crassatella (C. necopina sp. nov., C. personata sp. nov., C. singulata sp. nov.) from detrital sand of the Rybal'sky quarry of Dnepropetrovsk are described. Based on the study of additional material, the subspecies C. (C.) parisiensis Orbigny duplex Berezovsky, 2004 is ranked species (Upper Eocene; Ukraine Dnepropetrovsk, Ryba'sky quarry, Mandrikovka Beds). [ABSTRACT FROM AUTHOR]

It is found that adding boehmite nanoparticles to a sodium-carboxymethyl cellulose suspension with glycerin and aluminum powder allows the formation of films with ordered pores (cells of 1200-600 μm in size). X-ray diffraction and infra-red spectroscopy reveal no changes in the chemical composition of films upon their solidification. The surface porosity of the films is established to be 65%. The developed porous composites are shown to be promising in the fabrication of antifriction coatings. [ABSTRACT FROM AUTHOR]

Purpose: To determine gender-based normative values for pattern-reversal (PR) and flash (F) visually evoked potentials (VEP) under binocular and monocular stimulation in healthy adults. Methods: Healthy adults (age ≥18 years) were recruited among university employees and students. Inclusion criteria were absence of abnormalities in fundoscopy, tracking ability, stereopsis and pupillary reflexes; best-corrected visual acuity ≤.00 logMAR; and refractive error (spherical equivalent) from −6.00 to +6.00. Exclusion criteria were previous intraocular surgery, systemic and/or neurological disorders. Binocular and monocular tests were performed according to International Society for Clinical Electrophysiology of Vision standards for PRVEP (reversal rate = 1.9 Hz, checkerboard stimuli 15′ and 60′ at 100% contrast) and FVEP (3 cd s/m, rate = 1 Hz). VEP parameters of amplitude (µV) and peak times (ms) were measured. Inter-ocular differences, inter-peak intervals (N135-N75) and binocular summation were determined. Results: Fifty-four subjects (28 females; mean age = 40.4 ± 13.7 years; median = 40.0 years) were included. Mean P100 latencies for 15′ and 60′ stimuli were, respectively, 94.6 ± 4.7 ms and 96.1 ± 4.2 for women. Mean values of P100 latency for men were 97.4 ± 4.9 for 15′ and 97.7 ± 4.2 for 60′ stimuli. Larger mean P100 for 15′ checks was observed in women (12.8 ± 5.7 µV) than men (8.6 ± 2.5 µV) in PRVEP. Similar results were found for FVEP N2-P2 amplitudes (mean = 14.6 ± 4.9 for women and 9.8 ± 4.0 for men). Conclusions: Gender-based normative values for PRVEP and FVEP were determined, with women disclosing higher responses than men for smaller stimuli in the visual pathway. The use of gender-based normative values in the analysis of clinical VEP data for diagnostic and therapeutic purposes is recommendable. Additional analysis including inter-peak intervals and binocular summation ratio might improve the diagnostic power of VEP. [ABSTRACT FROM AUTHOR]

Two new bivalve genera and three new species of the family Limidae from the Upper Eocene of Ukraine are described. [ABSTRACT FROM AUTHOR]

Two new species of the genus Crassatella, C. imitatoris sp. nov. and C. pseudolamellosa sp. nov., from Upper Eocene detrital sands of the Rybal'sky quarry of Dnepropetrovsk are described. The species Crassatella oblongula Klushnikov, 1958 is redescribed as a variety. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate possible functional and structural ocular changes caused by chronic sildenafil therapy to treat pulmonary arterial hypertension (PAH). Methods: Case-control study included patients with pulmonary arterial hypertension: chronically using sildenafil and without sildenafil treatment. A comprehensive ophthalmologic exam including ectoscopy, extrinsic ocular motility, logMAR visual acuity measurement, contrast sensitivity test, color test, anterior segment biomicroscopy, Schirmer test 1, intraocular pressure, fundus exam under pupil dilation, fundus pictures, time domain and spectral domain optical coherence tomography, ocular Doppler ultrasound were performed. Full-field electroretinography (ERG) was tested for each eye in a subgroup of sildenafil-treated patients. Results: Twenty patients from each group were tested. Bilateral severe keratitis was found in seven (35 %) patients under sildenafil therapy. Lacrimal film break-up time (BUT) was significantly reduced ( p = 0.006 respectively) and Doppler ultrasound showed a reduced resistance index of the central retinal artery in the group of sildenafil users ( p = 0.019). No diffuse retinal functional abnormalities were found in ERG in treated patients. Visual acuity, contrast sensitivity and color discrimination were normal in both groups. No abnormalities were found in both time-domain and spectral-domain OCT for retinal parameters. Conclusions: One-third of the treated PAH group showed severe bilateral keratitis. This finding could be related to connective tissue abnormalities usually present in patients with this condition that might be exacerbated with the sildenafil usage. The resistance index of the central retinal artery was diminished in the chronic users group and it could be associated to the vasodilation caused by the medication in the choroidal vessels. An ophthalmic assessment for these patients is recommended to diagnose and treat possible ocular surface and choroidal blood flow abnormalities caused by sildenafil. [ABSTRACT FROM AUTHOR]

All presently known bivalve species of the orders Nuculida and Arcida with the taxodont hinge from the Upper Eocene of Dnepropetrovsk (Ukraine) are described and figured. The material includes private bivalve collection of the author collected from 1989 to 2013 and specimens collected by N.A. Sokolov, M.N. Klushnikov, S.V. Popov, O.V. Amitrov, I.A. Goncharova, L.S. Belokrys, V.V. Ablets, V.L. Stefansky, V.V. Dovben', and V.V. Dem'yanov, housed in the museums, scientific institutes, and private collections. The material comes from three localities: Rybal'sky quarry, village of Mandrikovka, and channel of the Dnieper River under the Amurskii railroad bridge. Revision is based on representative materials from the Rybal'sky quarry and specimens collected by N.A. Sokolov and M.N. Klushnikov. Previously published identification of species from the last two localities are revised. Photographs arranged in 33 plates display 56 species of the genera Arca, Barbatia, Asperarca, Acar, Venignia, Cucullaria, Siptionella, Arcopsis, Trigonodesma, Limopsis, Nucunella, Nucinella, Glycymeris, Nucula, Nuculana, and Yoldia. Of them 32 species are new. Two new genera, Venignia and Siptionella, are established. An extensive collection of shells from the Middle and Upper Eocene of Western Europe kindly placed at my disposal by the Netherlands paleontologist R. Hessel was of great importance for revision. [ABSTRACT FROM AUTHOR]

Two new genera and two new species of Mitilidae, Admytilus alius sp. nov. and Assytilus alpha sp. nov., from the Middle Eocene of a quarry near the town of Ingulets, Ukraine, are described. [ABSTRACT FROM AUTHOR]

Breast reconstruction has become standard of care for female patients with breast cancer. The transverse rectus abdominis musculo-cutaneous flap (TRAMf) is the most common method of immediate or delayed autologous breast reconstruction following mastectomy. We share our experience with modified, double back cut of post-mastectomy skin in delayed pedicled TRAMf breast reconstruction, resulting in fish-shaped skin paddle. This sort of back cut is a simple, reliable way to obtain a natural, esthetically pleasant breast mound with inconspicuous hidden scars. Level of Evidence V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors . [ABSTRACT FROM AUTHOR]

Five new bivalve species ( Limopsis obscura, L. indubia, L. lacunosa, L. pretiosa, and L. quadrata) from the Upper Eocene of Ukraine (Dnepropetrovsk, Rybal'sky quarry, Mandrikovka Beds) are described. [ABSTRACT FROM AUTHOR]

A new bivalve genus and species, Venignia arcula gen. et sp. nov. of the family Arcidae from the Upper Eocene of Ukraine is described. [ABSTRACT FROM AUTHOR]

Two new species of Asperarca, A. acuta and A. microida, from the Upper Eocene of the Ukraine (Dnepropetrovsk, Mandrikovka Beds) are described. This genus is recorded for the first time in the Paleogene. The most ancient previously known records of Asperarca were dated Miocene. [ABSTRACT FROM AUTHOR]

Cancer treatment-related chronic neuropathic pain (NP) is a pervasive and distressing problem that negatively influences function and quality of life for countless cancer survivors. It occurs because of cancer treatment-induced damage to peripheral and central nervous system structures. NP becomes chronic when pain signal transmission persists, eventually sensitizing neurons in the dorsal horn and other pain-processing regions in the central nervous system. Frequently overlooked, NP due to cancer treatment has been understudied. Consequently, only a few pharmacologic interventions have been shown to be effective based on the results of randomized controlled trials. Future research designed to explore pathophysiologic mechanisms and effective mechanism-targeted interventions is sorely needed. [ABSTRACT FROM AUTHOR]

A new genus of the family Parallelodontidae (Bivalvia: Arcoidea), Siptionella gen. nov., with four species from the Upper Eocene of Ukraine and Germany and the Maestrichtian of Denmark is described. From the Upper Eocene of Ukraine, two species, the type species of the genus S. prompta (Berezovsky, 2002), previously described by the author within the genus Porterius, and the new species S. demissa sp. nov. are described and figured. [ABSTRACT FROM AUTHOR]

New bivalve species of the genus Acar from the Upper Eocene of Dnepropetrovsk (Ukraine) are described. The differences in ontogenetic development of these species from the close genus Barbatia are discussed. [ABSTRACT FROM AUTHOR]

Purpose: To investigate contributing factors to visual evoked potential (VEP) grating acuity deficit (GAD) and inter-ocular acuity difference (IAD) measured by sweep-VEPs in children with cerebral visual impairment (CVI). Methods: VEP GAD was calculated for the better acuity eye by subtracting acuity thresholds from mean normal VEP grating acuity according to norms from our own laboratory. Deficits were categorized as mild (0.17 ≤ deficit < 0.40 log units), moderate (0.40 ≤ deficit < 0.70 log units) or severe (deficit ≥0.70 log units). Maximum acceptable IAD was 0.10 log units. Results: A group of 115 children (66 males-57 %) with ages ranging from 1.2 to 166.5 months (median = 17.7) was examined. VEP GAD ranged from 0.17 to 1.28 log units (mean = 0.68 ± 0.27; median = 0.71), and it was mild in 23 (20 %) children, moderate in 32 (28 %) and severe in 60 (52 %). Severe deficit was significantly associated with older age and anti-seizure drug therapy. IAD ranged from 0 to 0.49 log units (mean = 0.06 ± 0.08; median = 0.04) and was acceptable in 96 (83 %) children. Children with strabismus and nystagmus had IAD significantly larger compared to children with orthoposition. Conclusion: In a large cohort of children with CVI, variable severity of VEP GAD was found, with more than half of the children with severe deficits. Older children and those under anti-seizure therapy were at higher risk for larger deficits. Strabismus and nystagmus provided larger IADs. These results should be taken into account on the clinical management of children with this leading cause of bilateral visual impairment. [ABSTRACT FROM AUTHOR]

To investigate pattern-reversal visual evoked potentials (PRVEP) in asymptomatic maternally and non-maternally related members from a large Brazilian 11778/ND4 LHON pedigree. Transient PRVEP for check sizes 15′ and 60′ were recorded from asymptomatic mutation carriers and non-mutant descendants of affected/non-affected males, all with best-corrected visual acuity of 20/20. A control group of spouses (off-pedigree) was also included. Parameters of N75, P100 and N135 latencies (ms) and N75-P100 peak-to-peak amplitude (μV) as well as temporal dispersion (latency of N135-latency of N75) were determined. Longitudinal testing was obtained in a subseries of carriers in three annual consecutive visits. We tested 48 asymptomatic mutation carriers, 19 descendants of affected males, 9 descendants of non-affected males and 27 off-pedigrees, all of the latter being non-mutant. All non-mutant male descendants did not differ from off-pedigree controls. Statistically prolonged P100 latencies were found in mutation carriers ( P = 0.0143) when compared with off-pedigrees for check sizes 15′, as well as significantly larger temporal dispersions for both check size 15′ ( P = 0.0012) and check size 60′ ( P = 0.0271). Serial testing in 15 mutation carriers disclosed prolonged P100 latencies and larger temporal dispersion that did not change over time. Subclinical PRVEP abnormalities were detected in this large group of asymptomatic carriers of the 11778/ND4 LHON mutation from the same family, confirming and extending previous psychophysical and structural findings of a selective involvement of the parvocellular pathway. PRVEP is a useful test to characterize and monitor visual dysfunction in this devastating disease. [ABSTRACT FROM AUTHOR]

Tamoxifen, an effective treatment of breast cancer, has been shown to cause ocular toxic effects. The purpose of this study was to determine retinal toxicity by full-field and focal electroretinograms (ERGs) in patients treated with tamoxifen. Full-field and focal ERGs were obtained from three groups: Tamoxifen—14 females (47–72 years, mean 58.3 ± 9.1) with normal fundus, treated with tamoxifen from 2 to 37 months; No Treatment—10 females (39–65 years, mean 50.1 ± 8.7) with previous breast cancer diagnosis and before tamoxifen treatment; Control—13 normal female volunteers (41–81 years, mean 52.7 ± 12.1). Peak-to-peak amplitude and b-wave implicit time were measured and statistically analyzed. Mean peak-to-peak amplitudes and implicit time from full-field and focal ERGs were comparable for the three different groups. Low-dosage tamoxifen showed no retinotoxic effect assessed by full-field and focal ERG in this small group of women with breast cancer. [ABSTRACT FROM AUTHOR]

The motion of a system of interacting nonlinear charged oscillators is investigated numerically. Because of nonlinearity, the total collective electric field gives rise to a phasing effect—correlations in the phases of the oscillators. The consequence is superradiation—the enhanced spontaneous short-term emission of the energy stored in the oscillators. It is shown that the oscillations of the oscillators become stochastic because of the dipole-dipole interaction between them and their nearest neighbors. As a result, as the density of the oscillators increases, distant collective correlations are suppressed, superradiation ceases to be generated, and radiation is shielded in the medium. The phenomena considered in the present paper can play an important role in cyclotron emission from a plasma and thus should be taken into account in emission calculations. The process whereby the energy of the transverse electron motion in electron cooling devices decreases is analyzed as an example. This process occurs as a result of the development of cyclotron maser instability and has the nature of superradiation. The onset of correlations between individual electrons moving in their Larmor circles is the initial, linear stage of instability developing in the plasma. Superradiation is the final, nonlinear instability stage. [ABSTRACT FROM AUTHOR]

The ability to sequentially initialize, manipulate and read out the state of a qubit, such as an electron spin in a quantum dot (QD), is a requirement in virtually any scheme for quantum information processing. However, previous optical measurements of a single electron spin have focused on time-averaged detection, with the spin being initialized and read out continuously. Here, we monitor the coherent evolution of an electron spin in a single QD. We use time-resolved Kerr rotation (KR) spectroscopy, an all-optical, non-destructive technique that enables us to monitor the precession of the spin in a superposition of Zeeman-split sublevels with nanosecond time resolution. The data show an exponential decay of the spin polarization with time, and directly reveal the g-factor and spin lifetime of the electron in the QD. Furthermore, the observed spin dynamics provide a sensitive probe of the local nuclear spin environment. [ABSTRACT FROM AUTHOR]

In the field of quantum information science, semiconductor quantum dots (QDs) are of particular interest for their ability to confine a single electron for use as a qubit. However, to realize the potential offered by quantum information processing, it is necessary to couple two or more qubits. In contrast to coupling individual QDs, we demonstrate the integration of two coupled electronic states within a single QD heterostructure. These chemically synthesized nanocrystals, known as quantum-dot quantum wells (QDQWs), comprise concentric layers of different semiconducting materials. We investigate carrier and spin dynamics in these structures using transient absorption and time-resolved Faraday rotation measurements. By tuning the excitation and probe energies, we find that we can selectively initialize and read out spins in different coupled states within the QDQW. These results open a pathway for engineering coupled qubits within a single nanostructure. [ABSTRACT FROM AUTHOR]

Leber's hereditary optic neuropathy (LHON) is a maternally inherited disease, associated with mitochondrial DNA (mtDNA) point mutations and characterized by bilateral, usually sequential, rapid loss of central vision. The purpose of this study was to investigate electrophysiologically a small cohort of members from an extensive Brazilian family affected by LHON. Pattern-reversal visual evoked potentials (PVEP), and full-field electroretinograms (ERG) were performed on the four index members, all carrying the 11778 homoplasmic mtDNA mutation. They were a 14-year-old recently affected male, his unaffected mother, and her two affected brothers. The three affected members all had bilateral profound visual loss with visual acuities that ranged from 20/250 to CF, cecocentral defects, and severe dyschromatopsia (by FM-100). The unaffected (carrier) female had normal visual acuities, visual fields and color discrimination. Severely prolonged P100 latencies and decreased N75-P100 peak amplitudes were found in pattern-reversal VEPs for three affected members. Normal PVEP responses were found in the carrier female. Rod and cone ERG responses were normal in two affected members, but both the carrier mother and her affected son showed reduced peak-to-peak amplitude for single-flash cone response and 30 Hz flicker, with normal b-wave implicit times. Thus, optic nerve function, evaluated by PVEP, was severely reduced in LHON affected members and normal in the carrier female. However, reduced ERG cone responses suggest that LHON can also affect retinal elements, even in the absence of fundus and other clinical changes that constitute the full and classical expression of LHON. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine electroretinographic parameters according to the standard protocol from the International Society for Clinical Electrophysiology of Vision (ISCEV) in healthy preterm infants with normal fundus. Seventeen healthy preterm infants with normal fundus were recruited and divided in two age groups: 3-week group, nine infants with mean adjusted age at test = 2.67±0.92 weeks and 8-week group, eight infants with mean adjusted age at test = 7.92±1.72 weeks. Full-field ERGs were obtained with a Burian-Allen bipolar contact lens electrode from the anesthetized cornea in one eye, through a fully dilated pupil after 30 min of dark adaptation. The standard ISCEV protocol was used and the following responses were recorded: rod, maximal, oscillatory potentials, cone and 30 Hz flicker. Median values and 1st, 5th, 95th and 99th percentiles for amplitude and implicit time are described for both age groups. There was statistically larger amplitude for 30 Hz flicker (t=2.191; p=0.046) and for cone response (t=2.307; p=0.044) in the 8-week-old group. Statistically shorter implicit times were found in 8-week group for rod response (t=3.219; p=0.015), cone response (t=2.839; p=0.016) and flicker response (t=3.326; p=0.005). Shortening of implicit time was evident in the older group of preterms and this finding is consistent with other maturational studies confirming the anatomical and functional development of the photoreceptors. Medians and ranges between the 1st and 99th and the 5th and 95th percentiles can be used as a baseline for future comparisons with infants with ROP. [ABSTRACT FROM AUTHOR]

On the basis of recent basic developments in protein structure, a proteomic code is suggested, which would potentially allow the sequence, structure, and function of proteins to be described by a spectrum of elementary loop-n-lock units. All major characteristics of the nearly standard units are described, and the first five “codons” of the proteomic code are presented with their respective unique sequences, structures, and functions. More such codons are to be discovered, and the general procedure for their identification is described. [ABSTRACT FROM AUTHOR]