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Abstract We report on experimental and numerical investigation of burst-mode supercontinuum generation in sapphire crystal. The experiments were performed using bursts consisting of two 190 fs, 1030 nm pulses with intra-burst repetition rates of 62.5 MHz and 2.5 GHz from an amplified 1 MHz Yb:KGW laser and revealed higher filamentation and supercontinuum generation threshold for the second pulse in the burst, which increases with the increase of intra-burst repetition rate. The experimental results were quantitatively reproduced numerically, using a developed model, which accounted for altered material response due to residual excitations remaining after propagation of the first pulse. The simulation results unveiled that residual free electron plasma and self-trapped excitons contribute to elevated densities of free electron plasma generated by the second pulse in the burst and so stronger plasma defocusing, significantly affecting its nonlinear propagation dynamics. The presented results identify the fundamental and practical issues for supercontinuum generation in solid-state materials using femtosecond pulse bursts with very high intra-burst repetition rates, which may also apply to the case of single pulses at very high repetition rate, where residual material excitations become relevant and should be accounted for.

The objective of this study was to evaluate the association between dry period (DP) length and various indicators of productivity, reproduction, and udder health in cows managed with an automatic milking system. We analyzed records from 3861 cows, categorizing them into three groups based on their DP duration: (1) 70 days. Cows with a DP of 40–70 days had an average energy-corrected milk production that was 8.2 kg greater than that of cows with a short DP and 5.0 kg greater than that of cows with a long DP (p < 0.001). Milk from the 40–70-day DP group exhibited the highest lactose concentration (4.64 ± 0.01%). Additionally, cows with the longest DP had the smallest proportion of animals with a milk fat-to-protein ratio of 1.2 to 1.4. Cows with a DP of 40–70 days also showed the lowest milk electrical conductivity across all udder quarters, whereas cows with the shortest DP had the highest conductivity. The highest conception rates were observed in the group with the shortest DP. These results suggest that a DP of 40–70 days is optimal for maximizing milk production and improving both udder health and reproductive performance under AMS. Proper management of DP duration can be an effective strategy for sustainable dairy herd management.

This study aimed to assess the relationship between the length of the dry period (DL) and the risks of dystocia and stillbirths in Holstein cows. A total of 1072 healthy cows in lactations 1 and ≥2 were categorized based on the DL (mean: 58.07 ± 0.33 days) into three groups: short DL (70 days; 26.9%). Dystocia occurred in 12.4% of cows, while stillbirths accounted for 4.1% of calves. The medium DL group had the highest number of unassisted calvings. The dystocia rates were 11.4% for cows with gestation (GA) ≤ 274 days; 6.0% for cows with GA = 275–282 days; and 19.9% for cows with GA ≥ 283 days (p < 0.001). In season 1 (November–April), dystocia occurred in 15.0% of cases compared to 8.8% in season 2 (May–October) (p < 0.001). The stillbirth rates ranged from 3.6% to 4.0% for cows with medium and long DLs; while those with a short DL had 5.8% (p < 0.05). The stillbirth rates were 5.2% for cows with GA ≤ 274 days; 3.2% for cows with GA = 275–282 days; and 5.1% for cows with GA ≥ 283 days (p < 0.001). Season 1 had a stillbirth rate of 4.8%, while season 2 had a stillbirth rate of 3.3% (p < 0.001). This research provides insights that could assist the dairy industry in making informed decisions to reduce the incidence rates of dystocia and stillbirths in cows.

Abstract Background and purpose With a global increase in the burden of neurological diseases, the aversion towards neurology (neurophobia) may challenge the sufficient provision of new specialists in this field. We investigated the possible determinants of neurophobia among medical students and its influence on the intent to pursue neurology residency. Methods From September 2021 to March 2022, an online questionnaire was distributed to medical students in Lithuania. It included questions about knowledge, confidence, interest, and teaching quality of various medical specialties (including neurology), as well as the willingness to choose neurology for residency. Results Eight hundred fifty-two students responded to the survey (77.2% female) – they rated neurology as significantly more difficult than other medical areas and lacked confidence in assessing patients with neurological problems (p

Multiphoton photopolymerisation (MPP), also known as 3D nanoprinting, was studied using a wavelength-tunable femtosecond laser. The possibility of using any colour of the spectrum from 500 to 1200 nm with a fixed pulse width of 100 fs revealed an interplay of photophysical mechanisms more delicate than just two-photon photopolymerisation. An effective order of absorption, i.e. the X-photon absorption, as well as optimal exposure conditions were assessed for photosensitised and pure SZ2080$^{{\rm TM}}$ pre-polymer. The tunability of wavelength greatly influenced the dynamic fabrication window (DFW), optimised conditions resulting in a 10-fold increase. Furthermore, a non-trivial energy deposition by X-photon absorption was noted with an onset of a strong lateral size increase at longer wavelengths and can be understood as due to reaching epsilon-near-zero conditions. Such a control over the voxel aspect ratio and, consequently, the photopolymerised volume, may boost 3D nanoprinting efficiency. Overall, the results reveal wavelength being an important degree of freedom to tailor the MPP process and, if optimised, benefiting broad applications in areas of micro-optics, nanophotonic devices, metamaterials and tissue engineering.

The current report focuses on the analysis of the investigation results of the Abrikosov vortex motion in the YBa2Cu3O7-d (YBCO) device, which is a c-axis textured 0.3 ´ 50 ´ 100 µm3 (thickness ´ width ´ length) stripe of YBCO superconductor deposited on a LaAlO3 substrate. A laser beam focused in a Gaussian-shape optical spot of 5 mm in diameter modifies the stripe, initiating the oxygen out-diffusion and its uneven distribution in illuminated areas and in this way causing the appearance of a higher level of deoxygenation in the spot center and a lower level at its edges (slopes of weak superconductivity region). At temperatures below the temperature of the superconducting transition Tc, the current-self-produced magnetic field penetrates the optically modified area of the stripe in a form of Abrikosov magnetic vortices, and due to the current-self-produced Lorentz force, the vortices move toward their annihilation line resulting in energy dissipation. The vortices pinned on the slopes experience strong pinning and exert a magnetic drag force on moving vortices, which is confirmed by the stepped current-voltage dependences of the YBCO devices measured at temperatures 0.933·Tc £ T £ 0.958·Tc. Our results demonstrate the advantages of partially deoxygenated YBCO material for the development of superconducting electronic devices with electronic properties controlled by the motion of Abrikosov vortices at temperatures below Tc of the superconductor.

The dependence of the polymerization and optical damage thresholds in multi-photon polymerization (MPP) lithography was studied using a broadly-tunable laser system with group delay dispersion (GDD) control. The order of non-linearity and the light–matter interaction mechanisms were investigated using the resolution bridges method for non-photosensitized SZ2080TM and photosensitized SZ2080TM + IRG369 prepolymers. Energy deposition, voxel dimension growth, and the size of the dynamic fabrication window (DFW) were measured in the 700–1300 nm wavelength range at three different pulse durations measured at the sample – 100, 200 and 300 fs. Polymerization was observed at all wavelengths and pulse durations without significant differences in the achieved minimal spatial dimension (

The longshore realignment of nearshore sandbars is a morphodynamic phenomenon of multiple sandbar systems that has been known about for several decades. However, it is unknown how switching-related nearshore changes influence the evolution of subaerial beaches. This study aims to define the relationship between sandbar switching episodes and the dynamic state of the beach-foredune system along the Curonian Spit coast (Baltic Sea) using decadal satellite-derived and beach profiling data. To define this connection, sandbar switching locations, sandbar cross-shore positions, shoreline positions, and sand volume changes in the beach-foredune system were assessed on interannual and storm-related time scales. Twenty-seven sandbar switching episodes were observed with an average duration of 14.3 months. Most of the switching episodes occurred at preferred locations, coinciding with breaking points of different shoreline orientations where oblique waves and longshore currents prevailed. Shoreline retreat at an average rate of –14.2 m was observed within most of the sandbar switching zones. During major storm events, the average rate of erosion within the sandbar switching zones was significantly higher than the rate outside them. On an interannual time scale, a moderate average rate of erosion was observed within the sandbar switching zones compared to a small accretion rate outside them. Additional case studies of coastal evolution within the switching zones indicated well-correlated rates of switching-determined outer sandbar positions, shoreline positions, and sand volume on the beach and foredune during the switching episodes. The results of this study could be important for the identification of erosional hot spots and coastal prediction.

Abstract The formation and evolution of laser-induced periodic surface structures in fused silica under irradiation of widely tunable (in the 1–3 $$\upmu$$ μ m range) linearly polarized femtosecond (200 fs) pulses was studied experimentally. The structures were inscribed in high fluence regime (exceeding the surface ablation threshold for a single pulse) and characterized by using scanning electron microscopy and two dimensional Fourier transform. The results revealed rapid (after irradiation with a few successive pulses) formation of periodic laser-induced periodic surface structures aligned parallel to laser polarization, whose period increases with increasing the inscription wavelength, obeying the $$\lambda /n$$ λ / n law. With further increase of number of pulses, the generated structures gradually reorganize into laser polarization-independent low spatial frequency annular structures associated with formation of the damage crater, which fully established after irradiation with a few tens of successive laser pulses. This particular evolution scenario was observed over the entire wavelength tuning range of incident pulses.

Demonstration of generation of terahertz structured light in a form of configurable Airy beam for imaging aims and 2D materials inspection using exclusively flat silicon diffractive optics.

BackgroundSmartwatches are commonly capable to record a lead-I-like electrocardiogram (ECG) and perform a photoplethysmography (PPG)-based atrial fibrillation (AF) detection. Wearable technologies repeatedly face the challenge of frequent premature beats, particularly in target populations for screening of AF.ObjectiveTo investigate the potential diagnostic benefit of six-lead ECG compared to single-lead ECG and PPG-based algorithm for AF detection of the wrist-worn device.Methods and resultsFrom the database of DoubleCheck-AF 249 adults were enrolled in AF group (n = 121) or control group of SR with frequent premature ventricular (PVCs) or atrial (PACs) contractions (n = 128). Cardiac rhythm was monitored using a wrist-worn device capable of recording continuous PPG and simultaneous intermittent six-lead standard-limb-like ECG. To display a single-lead ECG, the six-lead ECGs were trimmed to lead-I-like ECGs. Two diagnosis-blinded cardiologists evaluated reference, six-lead and single-lead ECGs as “AF”, “SR”, or “Cannot be concluded”. AF detection based on six-lead ECG, single-lead ECG, and PPG yielded a sensitivity of 99.2%, 95.7%, and 94.2%, respectively. The higher number of premature beats per minute was associated with false positive outcomes of single-lead ECG (18.80 vs. 5.40 beats/min, P

Simple Summary: The goal of this study was to examine how the duration of the dry period is associated with milk production, health, and reproductive traits in a herd of cows managed with an automatic milking system. Cows with a dry period of 40–70 days showed higher energy-corrected milk production during the first 100 days of lactation compared to those with shorter or longer dry periods (p < 0.001). Additionally, cows in the 40–70-day dry period group exhibited the lowest milk electrical conductivity and somatic cell count, along with the highest milk lactose concentration. Mastitis pathogens were most prevalent in cows with the longest dry periods (>70 days), while Streptococcus agalactiae and Staphylococcus aureus were least detected in cows with a dry period of 40–70 days. The highest cow fertilization rate was observed in the group with the shortest dry period (<40 days). These findings provide insights that could help the dairy sector make informed decisions to enhance cow productivity and health. Moreover, managing dry period length effectively could serve as a critical tool for improving dairy herd management. The objective of this study was to evaluate the association between dry period (DP) length and various indicators of productivity, reproduction, and udder health in cows managed with an automatic milking system. We analyzed records from 3861 cows, categorizing them into three groups based on their DP duration: (1) <40 days, (2) 40–70 days, and (3) DP > 70 days. Cows with a DP of 40–70 days had an average energy-corrected milk production that was 8.2 kg greater than that of cows with a short DP and 5.0 kg greater than that of cows with a long DP (p < 0.001). Milk from the 40–70-day DP group exhibited the highest lactose concentration (4.64 ± 0.01%). Additionally, cows with the longest DP had the smallest proportion of animals with a milk fat-to-protein ratio of 1.2 to 1.4. Cows with a DP of 40–70 days also showed the lowest milk electrical conductivity across all udder quarters, whereas cows with the shortest DP had the highest conductivity. The highest conception rates were observed in the group with the shortest DP. These results suggest that a DP of 40–70 days is optimal for maximizing milk production and improving both udder health and reproductive performance under AMS. Proper management of DP duration can be an effective strategy for sustainable dairy herd management. [ABSTRACT FROM AUTHOR]

Abstract We compare supercontinuum generation in $$\hbox {CaF}_2$$ CaF 2 crystal under tight and loose focusing of 150 fs, 515 nm second harmonic pulses from an amplified Yb:KGW laser at a repetition rate of 10 kHz. It is demonstrated that supercontinuum generation geometry applying loose focusing ( $$\hbox {NA}=0.004$$ NA = 0.004 ) of the pump beam into a long (25 mm) $$\hbox {CaF}_2$$ CaF 2 sample is advantageous in terms of supercontinuum spectral extent and durability of damage-free operation of the nonlinear material as compared to a commonly used supercontinuum generation setup which employs tight focusing ( $$\hbox {NA}=0.012$$ NA = 0.012 ) into a short (5 mm) sample and to setup which uses tight focusing into a long (25 mm) sample. More specifically, loose focusing into a long sample showed remarkably longer (20 min) damage-free operation of the nonlinear material, which was not translated with respect of the pump beam, while in tight focusing condition the sample is damaged just within 2 min of operation, leading to a complete extinction of the supercontinuum spectrum. The evolution of optical degradation of the nonlinear material in time and its impact to supercontinuum spectrum is studied in terms of filament-induced luminescence due to self-trapped exciton emission and light scattering at the pump wavelength indicating the onset of optical damage. Our findings are supported by the numerical simulations which compare relevant parameters related to filament propagation in tight and loose focusing conditions.

Femtosecond laser-assisted material surface modification is a rapidly growing field with numerous applications, including tribology, micromechanics, optofluidics, and medical implant treatment. For many of these applications, precise control of surface roughness after laser treatment is crucial, as it directly affects the final properties of the work surface. However, achieving low mean surface roughness values (

Superficial modifications on silicon wafers produced by single-shot focused femtosecond laser irradiation having a 1030 nm wavelength and 300 fs pulse duration were experimentally and theoretically analyzed. The laser fluence window when the amorphous silicon phase develops, resulting in a ring-like modification shape, was experimentally estimated to be between 0.26 J/cm2 and 0.40 J/cm2 and was independent of the silicon dopant type and laser focusing conditions; however, the window was narrower when compared to results reported for shorter pulse durations. In addition, we present a simplified numerical model that can explain and predict the formation of these patterns based on the caloric coefficients of silicon and the energy distribution of the deposited material.

The marking and surface structuring of various materials is important in various industrial fields such as biomaterials, luxury goods, anti-counterfeiting, automotive and aerospace, electronics and semiconductor industries, and others. Recent advances in laser technology, such as burst-mode lasers, have opened new ways of affecting the surfaces of various materials, inducing a different appearance and/or properties of the laser-exposed areas. From earlier studies, it is known that when splitting a single pulse into multiple pulses and thus creating a quasi-MHz–GHz repetition rate regime, it is possible to increase not only the ablation efficiency but it also provides the possibility to tune the heat in-flow into the surface. Such new regimes enable the control of the surface roughness as well as the optical properties and corrosion resistance. In this work, we analyze the effect of the different burst-mode regimes for the marking of stainless-steel samples, aiming to produce high-contrast marking having different shades of black/white color (black-gray-white). Moreover, we investigate the angular dependence of the reflected light after laser treatment numerically from the measured surface morphology

Abstract Abdominopelvic vascular compression syndromes include a variety of uncommon conditions characterized by either extrinsic compression of blood vessels by adjacent anatomical structures (i.e., median arcuate ligament syndrome, nutcracker syndrome, May-Thurner syndrome) or compression of hollow viscera by adjacent vessels (i.e., superior mesenteric artery syndrome, ureteropelvic junction obstruction, ureteral vascular compression syndromes, portal biliopathy). These syndromes can be unexpectedly diagnosed even in asymptomatic patients and the predisposing anatomic conditions can be incidentally discovered on imaging examinations performed for other indications, or they can manifest with atypical abdominal symptoms and acute complications, which may lead to significant morbidity if unrecognized. Although computed tomography (CT) is an accurate noninvasive technique for their detection, the diagnosis remains challenging due to the uncommon clinical presentation and often overlooked imaging features. Dynamic imaging may be performed in order to evaluate patients with inconstant symptoms manifesting in a specific position. The purposes of this paper are to review the CT imaging findings of abdominopelvic vascular compression syndromes, correlating with anatomical variants and to provide key features for the noninvasive imaging diagnosis.

Neurophobia can be defined as a fear of neurosciences and clinical neurology experienced by students, residents, and doctors due to their inability to apply their knowledge of basic sciences to clinical situations. The concept of neurophobia was first mentioned by Ralph Jozefowicz in 1994, but only in 2002 neurophobia was scientifically proven. Since then, research around the world has shown that medical students rate neurology as the most complex discipline, have the lowest level of confidence in their neurological knowledge, and feel the least confident in their competencies when assessing patients with neurological problems. Neurophobia is thought to be caused by: too short a training period, poor study quality, complex neuroanatomy, difficult neurological examination, neurology training by a non-practicing neurologist, and the stigma that neurologists are dissatisfied with their profession. Medical students and doctors find neurology difficult. Understanding the causes of neurophobia and promoting neurophilia would not only increase the willingness of medical students to choose the profession of neurologist, but also improve the care and treatment of patients with neurological diseases.

Long-term observations of nearshore bar behaviour are a vital component of coastal monitoring, management, and prediction. Optical satellite remote sensing enables the possibility of such observations over large spatial areas, but its full potential remains unexploited. This study assessed alongshore variability in cross-shore nearshore bar behaviour on a wave-dominated multi-bar coast of the Curonian Spit (south-eastern Baltic Sea) between 2011 and 2021, using satellite-derived bar data. Nearshore bars were extracted from a time series of PlanetScope and RapidEye satellite images with an automated GIS-based algorithm, previously proposed by the study authors. The cross-shore behaviour of a multiple bar system was analysed by adapting traditional bathymetry-based analysis techniques to satellite-derived data that included bar crestlines and images of multi-scale Relative Bathymetric Position Index (RBPI). The analysis was performed on 1071 shore-perpendicular transects. Multi-bar onshore and offshore migration rates were quantified on interannual and seasonal timescales. The results show that, on an interannual timescale, bars migrated offshore at rates up to 9.7 m/month, while the rates of onshore migration reached up to 11 m/month. During the months of low wave energy, bars moved offshore at rates up to 6.2 m/month, and during the months of high wave energy, up to 12.9 m/month. However onshore migration rates, during the months of low and high wave energy, reached up to 7.0 and 13.4 m/month, respectively. A complex empirical orthogonal function (CEOF) analysis was performed on RBPI-derived cross-shore profiles, and cyclic offshore directed bar behaviour was examined. For the first time, the net offshore migration (NOM) cycle with bar cycle return periods of 1.8 to 13.5 years was investigated on the south-eastern Baltic Sea coast. Bar cycle return periods increased and rates of bar cross-shore migration decreased from north to south along the Curonian Spit. Similar nearshore bar behaviour regions were identified using clustering analysis based on quantified temporal and morphological characteristics of the bars. Factors controlling alongshore variability in bar cross-shore behaviour were determined. The study results suggest that small alongshore variations in nearshore hydrodynamics, caused by the local wave climate and its interplay with the shoreline orientation, determine the morphological and temporal variability of the multi-bar system in the Curonian Spit.

Energy dissipation from vortex motion, which appears as a resistivity of the mixed-state superconductor, limits the range of type II superconductors in low- and high-power electronics and optoelectronics. The level of dissipation increases with the development of the vortex motion phase from that of the thermally activated flux flow to that of the flux creep and finally to that of the flux flow. The vortex motion regimes depend on the balance between bias current-self-produced Lorentz force, accelerating vortices, and the pinning force, which, together with a magnetic drag force from pinned vortices, tends to stop the vortex motion. The current paper reports on energy dissipation in YBa2Cu3O7-δ (YBCO) devices provided with partially deoxygenated structures mutually interacting by magnetic force with one another. The shape of the structure and the magnetic interaction between the trapped and moving vortices, as well as the magnetic interaction between neighboring structures, can cause the appearance of voltage steps in the device’s current–voltage characteristics observed in temperature range 0.94 ≥ T/Tc ≥ 0.98 (here, Tc = 91.4 K is the temperature of the superconducting transition in the YBCO material). Current findings demonstrate the potential of artificial structures to control vortex motion in a mixed-state YBCO superconductor by means of a temperature, bias current, and a specific configuration of the structure itself and a profile of the oxygen distribution in it.

Serum- and glucocorticoid-regulated kinases (SGKs) are members of the AGC family of serine/threonine kinases, consisting of three isoforms: SGK1, SGK2, and SGK3. SGK1 was initially cloned as a gene transcriptionally stimulated by serum and glucocorticoids in rat mammary tumor cells. It is upregulated in some cancers and downregulated in others. SGK1 increases tumor cell survival, adhesiveness, invasiveness, motility, and epithelial to mesenchymal transition. It stimulates tumor growth by mechanisms such as activation of K+ channels and Ca2+ channels, Na+/H+ exchanger, amino acid and glucose transporters, downregulation of Foxo3a and p53, and upregulation of β-catenin and NFκB. This chapter focuses on major aspects of SGK1 involvement in cancer, its use as biomarker as well as potential therapeutic target.