Line Depth Research Articles

Mechanical criteria and analytical modeling of mixed-state wetting on multiscale surfaces: Of the importance of nanoscale topography for water-repellency

Multiple natural surfaces exhibit excellent water-repellent properties. Such surfaces systematically demonstrate multiscale surface topographies. However, current mechanical criteria for composite-wetting equilibrium can only be applied on model micrometric pillars. This paper suggests a theoretical basis on the foundation of which we introduce multiscale mechanical criteria for mixed-state equilibrium on real surfaces. A method for the analytical modeling of mixed-state wetting on real textured surfaces and the retrieval of critical wetting parameters such as the total solid-liquid contact area and the total triple line perimeter at the effective anchorage depth is introduced. This method is applied to the case of the sacred Lotus leaf on which we predict the effective anchorage depth of the triple lines. Results show that the nanoscale topography of these leaves leads to the minimization of the effective anchorage depth of the droplet on the sides of the micrometric asperities, a determining parameter with regards to its effect on the total solid-liquid contact area and the total triple line perimeter, unveiling a little more the role of nanoscale wax crystals in nature’s strategies for water-repellency.

Local impedance drop guided versus lesion size index guided pulmonary vein isolation: long-term outcomes and chronic reconnections

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Insufficient lesion depth and discontinuity of lesion lines are reasons for reconnections after point-by-point radiofrequent pulmonary vein isolation (PVI). Different technologies have shown to be useful for prediction of effective lesions. Measurement of the magnitude of local tissue impedance drop (LID) and calculation of lesion size index (LSI) based on monitoring of contact force are examples for corresponding technologies. Purpose To compare the long-term outcomes of LID guided with LSI guided PVI. Methods In this retrospective study we compared two groups of patients who underwent point-by-point radiofrequency PVI for treatment of atrial fibrillation. In the LID-guided group (n=35) energy was delivered using an ablation catheter with local impedance monitoring. Ablation was terminated when LID reached a plateau (Fig. A). In the LSI-guided group (n=31) lesions were created using an ablation catheter with contact force monitoring until the target LSI was reached in each point (LSI=5 for anterior and LSI=4 for posterior segments, respectively, Fig B). The inter-lesion distance of <6 mm with power of 40 W for anterior and 30W for posterior segments was used in both groups. A gap-map and touch-up ablation was performed along the index ablation line if the first pass PVI did not occur, or in the case of an acute reconnection after 20 min of waiting time. In the long-term follow-up, a holter ECG was scheduled 3, 6 and 12 months after the initial ablation as well as symptom-driven visits with ECG registration. In case of symptomatic arrhythmia recurrence, a second procedure was performed including validation of PVI, mapping of reconnection site and RePVI, if necessary. Results All pulmonary veins were successfully isolated by encirclement of ipsilateral veins during initial procedure. During the 11.5±2.9 months follow-up, 12 out of 35 (34.3%) patients from LID-guided group and 5 out of 31 (16.1%) patients from LSI-guided group experienced arrhythmia recurrence. Kaplan-Meier survival analysis showed statistically significant higher probability of the arrhythmia recurrence in patients treated with LID-guided approach (log-rank=4.37, p=0.037, Fig C). Redo procedure was performed for 10 (28.6%) patients in LID-guided group and 3 (9.7%) patients in LSI-guided group and chronic pulmonary vein reconnections were detected in 7 out of 10 (70%) and 2 out of 3 (67%) patients, respectively (Fig D). Conclusions Despite initial successful isolation of all pulmonary veins, LID-guided ablation resulted in significantly higher probability of arrhythmia recurrence during the long-term follow-up as well as higher rate of chronic PV reconnections (although not statistically significant) as compared to LSI-guided ablation. This reflects the nature of contact force guided ablation anticipating the quality of catheter-tissue interface before each application, which is not possible with an impedance only guided approach.

Local impedance drop guided versus lesion size index guided pulmonary vein isolation: acute success and reconnections

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Insufficient lesion depth and discontinuity of lesion lines are reasons for reconnections after point-by-point radiofrequency pulmonary vein isolation (PVI). Different technologies have shown to be useful for prediction of effective lesions. Measurement of the magnitude of local tissue impedance drop (LID) and calculation of lesion size index (LSI) based on monitoring of contact force are examples for corresponding technologies. Purpose To compare the acute efficacy of LID guided with LSI guided PVI. Methods In this retrospective study we compared two groups of patients who underwent point-by-point radiofrequency PVI for treatment of atrial fibrillation. In the LID-guided group (n=35) energy was delivered using IntellaNav MiFi (Boston Scientific, MA, USA) ablation catheter. Ablation was terminated when LID reached a plateau (Figure A). In the LSI-guided group (n=31) lesions were created using Tacticath (Abbott, MA, USA) ablation catheter until the target LSI was reached in each point (LSI=5 for anterior and LSI=4 for posterior segments respectively, Figure B). The inter-lesion distance of <6 mm with power of 40 W for anterior and 30W for posterior segments was used in both groups. A gap-map and touch-up ablation was performed along the index ablation line if the first pass PVI did not occur, or in the case of an acute reconnection after 20 min of waiting time. In the post hoc analysis initial levels and drop of local and system impedance, average contact force and LSI were included in models predicting PV gaps. Results All PVs were successfully isolated by encirclement of ipsilateral veins with significantly longer median ablation time 30(IQR:27-35) min in LID-guided group as compared to LSI-guided group:25 (IQR:21-31) min (p=0.035). First-pass PVI was achieved in 97 out of 132(73%) circles (LID-guided:43 out of 70 [61%] circles vs LSI-guided:54 out of 62 [87%] circles, p=0.002). Acute reconnections occurred in 14 out of 132 (11%) circles (LID-guided:9 out of 70 [13%] circles vs LSI-guided: 5 out of 62 [8%] circles, p=0.54, Figure C). Overall, significantly more patients had PV gaps when LID-guided ablation was used as compared to LSI-guided (26 out of 35[74%] vs 13 out of 31[42%] respectively, p=0.016). In the post hoc analysis a LID<9.7Ω was the only predictive parameter for PV gap (sensitivity=96.4%, specificity=67%). Conclusions LSI-guided ablation resulted in successful PVI with significantly shorter ablation time and fewer PV gaps as compared to LID-guided. This reflects the nature of contact force guided ablation anticipating the quality of catheter-tissue interface before each application, which is not possible with an impedance-only guided approach.

Comparison Between Pulsed and Continuous Accelerated Corneal Cross-Linking Protocols.

To compare between two accelerated corneal cross-linking (A-CXL) protocols in the management of keratoconus (KC) as regard to the extent of corneal treatment. This retrospective, comparative study included patients having mild to moderate, progressive KC. The study population was divided into two groups; group 1 enrolled 103 eyes of 62 patients who received pulsed light A-CXL (pl-CXL) at a power of 30 mW/cm2 with an irradiation time of 4 minutes, while group 2 comprised 87 eyes of 51 patients who received continuous light A-CXL (cl-CXL) at a power of 12 mW/cm2 with an irradiation time of 10 minutes. Recordings of the central and peripheral demarcation line depths (DD), and the maximum (DDmax) and minimum (DDmin) DD, using anterior segment optical coherence tomography, were compared between the two studied groups one month after the treatment protocol. Treatment stability was also evaluated pre and postoperatively (one year following surgery) by comparing the refractive and keratometric outcomes in both groups. The differences between the preoperative corneal thickness (minimum and central) and the epithelial thickness measurements between both groups were not statistically significant. Although group 1 had slightly larger central DD (223.4 ± 62.3 um), DDmax (240.4 ± 61.8 um), and DDmin (201 ± 54 um) than those of group 2 (221.8 ± 37 um, 229.1 ± 38.4 um, and 212 ± 37.2 um, respectively), the differences between both groups' measurements were not statistically significant. Also, the two groups showed statistically insignificant differences regarding the subjective refraction and the average and maximum keratometry pre and postoperatively, denoting visual, refractive, and keratometric stability in both groups. Longer duration cl-CXL seems to be as effective as pl-CXL regarding both postoperative stability and the extent of corneal tissue penetration by the ultraviolet treatment.

The effect of accelerated pulsed high-fluence corneal cross-linking on corneal endothelium; a prospective specular microscopy study

BackgroundCorneal collagen cross-linking (CXL) is a procedure utilized for halting keratoconus progression with different approved protocols. The current study aimed to assess the corneal endothelial changes following the relatively new accelerated pulsed high-fluence protocol of epithelium-off corneal cross-linking for the treatment of mild to moderate keratoconus.MethodsThis prospective case series study enrolled 45 eyes of 27 patients with mild to moderate progressive keratoconus who underwent accelerated pulsed high-fluence CXL (pl-ACXL, 30 mW/ cm2 UVA at 365 nm wavelength, 8 min pulsed mode 1 s on / 1 s off with a total energy of 7.2 J/ cm2). The main outcome measures were corneal endothelial changes assessed by specular microscopy at 3 and 6 months postoperatively including endothelial cell density (ECD), coefficient of variation, percentage of hexagonal cells, average, minimum and maximum endothelial cell sizes. Demarcation line depth was assessed 1 month following surgery.ResultsThe mean age of the studied sample was 24.89 ± 7.21. The mean preoperative ECD (2944.6 ± 247.41 cell/mm2) showed non-significant reduction at 3 and 6 months postoperatively (2931.03 ± 253.82 and 2924.7 ± 224.88 cell/mm2, respectively, P-value = 0.361). There were no significant changes in the mean coefficient of variation, percentage of hexagonal cells, average, minimum and maximum endothelial cell sizes at 3 and 6 months following pl-ACXL (P-value > 0.05). The mean demarcation line depth 1 month after pl-ACXL was 214 ± 17.43 μm.ConclusionsCorneal endothelial changes following accelerated pulsed high-fluence CXL were minimal with stability of endothelial cell count and non-significant morphological changes.Trial RegistrationClinicaltrials.gov: NCT04160338 (13/11/2019).

Research on the Factors Affecting the Formation of Ore-Free Zone at Blast Furnace Throat Based on DEM

The ore-free zone in the center of the blast furnace throat is a major feature of the charging system, ensuring the permeability of the center. Factors that influence the formation of the ore-free zone need to be researched to increase the control precision. In this paper, on the basis of a 1:1 3D model of a blast furnace, the formation of an ore-free zone at the burden surface at the throat was simulated by using the discrete element method (DEM). The effects of burden line depth, batch weight, and distribution angle on the formation of ore-free zones were investigated. The results showed that with increasing burden line depth, the width of the ore-free zone increased, the thickness decreased, the ore-to-coke ratio decreased, and the central airflow developed. Only changing the ore batch weight affected the thickness and width of the ore-free zone and had a greater impact on the permeability of the ore-free zone. The greater the ore batch weight was, the worse the permeability, while changing the batch weight of both coke and ore mainly affected the thickness of the ore-free zone. The greater the batch weight of coke and ore was, the greater the thickness of the ore-free zone. In the case of changing only the angle of ore in the matrix, with the angle increasing, the ore-to-coke ratio around the ore-free zone decreased, the ore-to-coke ratio around the furnace wall increased, and the edge airflow was suppressed. In the case of changing the angle of coke and ore at the same time, with the simultaneous increase in both angles, the ore-free area was compressed in the direction of smaller charge segregation, the area with better permeability in the center of the furnace throat was reduced, and the central airflow was suppressed.

Does partial adhesive preparation design and finish line depth influence trueness and precision of intraoral scanners?

Statement of problemIntraoral scanners (IOSs) are widely used for partial-coverage adhesive restorations, but data on their performance in such preparations with complex geometries are sparse. PurposeThe purpose of this in vitro study was to investigate whether the partial-coverage adhesive preparation design and finish line depth affect the trueness and precision of different IOSs. Material and methodsSeven partial-coverage adhesive preparation designs (4 different onlays, 2 endocrowns, and 1 occlusal veneer) were tested on copies of the same tooth placed in a typodont mounted on a mannequin. Each preparation was scanned 10 times with 6 different IOSs (total 420 scans) under the same light conditions. Trueness and precision, defined according to the International Organization for Standardization (ISO) 5725-1 standard, were analyzed with a best-fit algorithm by superimposition. The obtained data were analyzed by a 2-way analysis of variance to examine the effects of partial-coverage adhesive preparation design, IOS, and their interactions (α=.05). ResultsSignificant differences were found among different preparation designs and IOSs (P<.05) in terms of both trueness and precision. Significant differences were also found among mean positive and negative values (P<.05). Moreover, crosslinks observed between the preparation area and the adjacent teeth correlated with the finish line depth. ConclusionsComplex partial adhesive preparation designs affect the trueness and precision of IOSs, resulting in significant differences among them. Interproximal preparations should take into account the IOS’s resolution and placing the finish line close to adjacent structures should be avoided.

Center-to-limb variation of spectral lines and continua observed with SST/CRISP and SST/CHROMIS

Context.Observations of center-to-limb variations (CLVs) of spectral lines and continua provide a good test for the accuracy of models with a solar and stellar atmospheric structure and spectral line formation. They are also widely used to constrain elemental abundances, and are becoming increasingly more important in atmospheric studies of exoplanets. However, only a few such data sets exist for chromospheric lines.Aims.We aim to create a set of standard profiles by means of mosaics made with the CRISP and CHROMIS instruments of the Swedish 1-m Solar Telescope (SST), as well as to explore the robustness of said profiles obtained using this method.Methods.For each spectral line, we used a mosaic that ranges from the center to the limb. Each of these mosaics were averaged down to 50 individual spectral profiles and spaced by 0.02 in theμscale. These profiles were corrected for p-mode oscillations, and their line parameters (equivalent width, line shift, full-width at half-maximum, and line depth) were then compared against literature values whenever possible.Results.We present a set of 50 average profiles that are spaced equidistantly along the cosine of the heliocentric angle (μ) by steps of 0.02 for five continuum points between 4001 and 7772 Å, as well as ten of the most commonly observed spectral lines at the SST (Ca II H &amp; K, Ηβ, Mg I 5173 Å, C I 5380 Å, Fe I 6173 Å, Fe I 6301 Å, Ha, O I 7772 Å, and Ca II 8542 Å).Conclusions.The CLV of line profiles and continua are shared in the CDS as machine readable tables, providing a quantitative constraint on theoretical models that aim to model stellar atmospheres.

Molecules in the peculiar age-defying source IRAS 19312+1950

Context. IRAS 19312+1950 is an isolated infrared source that exhibits a characteristic quasi-point-symmetric morphology in the near-and mid-infrared images and is also very bright in molecular radio lines. Because of its unique observational characteristics, various observational studies have been conducted and several hypotheses have been proposed regarding its origin, which is still unclear. So far, it has been suggested that it could be a peculiar evolved star, a young stellar object, or even a red nova remnant. Regardless of which type of object it is ultimately classified as, IRAS 19312+1950 is exceptionally bright in the infrared and molecular radio lines and therefore will undoubtedly be crucial as a prototype of this kind of object having a peculiar nature or unusual evolutionary phase. Aims. This study aims to reveal the molecular composition of the central part of IRAS 19312+1950 by performing an unbiased molecular radio line survey and discussing the origin of the object from a molecular chemical point of view. Methods. We carried out a spectral line survey with the Institut de Radioastronomie Millimtrique 30 m telescope towards the centre of IRAS 19312+1950 in the 3 and 1.3 mm windows with a frequency coverage of 83.9–91.8 and 218.2–226.0 GHz, respectively. Results. In total, 28 transition lines of 22 molecular species and those isotopologues are detected towards IRAS 19312+1950, some of which exhibit a broad and a narrow component. Seventeen thermal lines and one maser line are newly detected. The molecular species of C17O, 30SiO, HN13C, HC18O+, H2CO, and c-C3H2 are detected for the first time in this object. We calculated the optical depths of the transition lines of 13CO, C18O, HCN, H13CN, and C2H, and determined the rotational temperatures, column densities, and fractional abundances of the detected molecules. We got the isotopic ratios of 12C/13C, 14N/15N, 16O/18O, 16O/17O, 18O/17O, 28Si/30Si, and 29Si/30Si in IRAS 19312+1950 and the values were compared to those of evolved stars, red novae, young stellar objects, and the Sun. The intensities of the molecular radio lines of IRAS 19312+1950 were compared with those of different categories of objects, indicating that the spectral pattern of the broad-line region is similar to that of a red nova or a low-mass young stellar object, while the narrow-line region behaves like an envelope of the asymptotic giant branch star. Conclusions. Our results, in combination with previous studies, favour the hypothesis that IRAS 19312+1950 might be a red nova remnant, in which the progenitors that merged to become a red nova may have contained at least two evolved stars with oxygen-rich and carbon-rich chemistry, respectively.

SVP Inversion for Weakening Multibeam Bathymetry Errors by Constraint of Check Line Depth

SVP Inversion for Weakening Multibeam Bathymetry Errors by Constraint of Check Line Depth

Laser-based monolithic series interconnection of two-terminal perovskite-CIGSe tandem solar cells: determination of the optimal scribe line properties

To achieve a monolithic series interconnection of tandem solar cell devices consisting of a perovskite top cell and a CIGSe bottom cell, a two-terminal interconnection scheme is introduced that includes an additional, fourth patterning step, the so-called iso-cut, which separates the window layer stack between the two solar cells. The implementation of this interconnection scheme requires a process development for a total of four structuring steps, which was achieved by systematically varying the laser parameters. Based on a detailed characterization of the individual scribe line properties with respect to their scribe line depth, morphology, electrical functionality, chemical composition and their influence on adjacent and underlying layers, the optimal patterning parameters and suitable process windows were derived for each step, which is a prerequisite for a loss-free monolithic series interconnection in a tandem module.

Effect of Surface Roughness on the Electrical Performances of CPW Transmission Lines Used in Future Ultra-High Frequency Applications.

The development of integrated circuits and packaging technology has led to smaller and smaller transmission line sizes and higher and higher operating frequencies up to nearly 100 GHz. However, the skinning depth of transmission lines due to eddy currents becomes smaller and smaller as the operating frequency of coplanar wave guide (CPW) transmission lines becomes higher and higher, while the reduction of device size makes the skinning depth consistent with the surface roughness of the device. In this paper, the concept of modified roughness coefficient was proposed based on the existing correlation factor. The concept of threshold modified roughness coefficient was proposed with a 20 dB reflection coefficient as the threshold value. The effect of surface roughness on transmission line transmission performance at frequencies above 100 GHz up to 1000 GHz was investigated. It was found that when the operating frequency of the signal was greater than the threshold roughness coefficient, the effect of surface roughness on the transmission line reflection coefficient should be considered. The modified roughness coefficient in this paper could quickly determine the effect of surface roughness on transmission line performance at different frequencies.

Comparison of Corneal Stromal Demarcation Line Depth in Epi-off and Epi-on Corneal CrossLinking Using Anterior Segment Optical Coherence Tomograph

Objective: To compare the corneal stromal demarcation line depth after Epithelium-On and Epithelium-Off corneal crosslinking in patients with keratoconus using anterior segment Optical Coherence Tomography (AS-OCT).&#x0D; Study design: Quasi-experimental study.&#x0D; Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi Pakistan from Jun 2018 to Jun 2019.&#x0D; Methodology: This study included patients (60 eyes) with progressive keratoconus treated with procedure CXL (corneal cross linkage). There were 30 eyes in each group. Two different protocols of Corneal cross linkage were performed, and patients were divided into two groups according to protocol: 1) epithelium-on Corneal cross-linkage, 2) epithelium-off Corneal crosslinkage. In the First-Group, epithelium-on Corneal cross-linkage,corneal epithelium was not removed, riboflavin solution was instilled on the cornea for one hour, and the cornea was exposed to Ultraviolet A rays. In Epithelium off Corneal cross-linkage,after epithelium was removed by spatula, riboflavin solution was instilled for 30 minutes, and Ultraviolet-A rays were focused on the cornea. After one month of the procedure, Anterior segment Optical Coherence Tomography was performed.Demarcation line depth was measured in treated corneas in all patients from both groups, and findings were compared.&#x0D; Results: The stromal demarcation line depth was similar in both groups, and there was no statistical difference between the groups. The mean value of demarcation line depth was 277.13±107.09 цm (p&gt;0.05).&#x0D; Conclusion: Corneal stromal demarcation line depth after both procedures was similar in both groups after one month of Corneal cross-linkage, so it was concluded that epithelium-on Corneal cross-linkage was comparable to epithelium-off Corneal cross-linkage.

Corneal biomechanical stiffness and histopathological changes after in vivo repeated accelerated corneal cross-linking in cat eyes

Corneal cross-linking (CXL) has been proved efficiency for treating progressive keratoconus and other corneal ectasia diseases by stabilizing corneal geometry and biomechanics. However, the necessity of repeated CXL treatment in patients is unknown. This study aimed to investigate corneal biomechanical stiffness and change in corneal histopathological characteristics after repeated accelerated CXL (A-CXL) in cat eyes. A-CXL was performed with 0.1% riboflavin applied for 10 min, followed by ultraviolet A irradiation at 30 mW/cm2 for 3 min at 365 nm in 15 domestic cats. Corneas (n = 30) were divided into three groups: one-time accelerated corneal cross-linking (A-CXL*1 group), repeated accelerated corneal cross-linking (A-CXL*2 group), and an untreated control group. In A-CXL*2 group, A-CXL was repeated at 1-month intervals. In vivo ocular examinations were performed pre- and postoperatively. Biomechanical analysis was performed using a biotester biaxial testing system. We used the Mooney–Rivlin strain-energy function to describe corneal material properties. No infection in any case after A-CXL was observed. Biomechanical tests showed that the stress-strain curves of the two A-CXL groups were significantly different from those of the control group (P < 0.01), whereas stress-strain curve of the A-CXL*2 group was similar to that of the A-CXL*1 group (P > 0.05). Delayed epithelial healing and haze were observed 1 month after surgery. Stromal demarcation line depth measured with anterior spectral-domain optical coherence tomography was 187.6 ± 20.4 and 197.1 ± 11.5 μm for the A-CXL*1 and A-CXL*2 groups, respectively (P > 0.05). These results show that A-CXL can increase corneal biomechanics in cat eyes. The biomechanical enhancement of cat corneas treated with repeated A-CXL at 1-month intervals was similar to that of performing a one-time A-CXL. Repeated cross-linking procedures at short intervals may increase the risk of adverse reactions, and more caution should be taken in clinical applications.

Corneal stromal demarcation line depth after corneal collagen cross-linking following conventional versus customized corneal epithelial debridement

Aim of the Study: Using anterior segment optical coherence tomography (AS-OCT) to compare the depth of corneal demarcation line (DL) after corneal collagen cross-linking (CXL) with subtotal versus customized corneal epithelium debridement. Design: Prospective multi centric case-control study. Materials and Methods: The study enrolled 18 patients with bilateral progressive keratoconus. Both eyes treated by CXL using 3 mW/cm2 / 30 minutes setting. One eye with subtotal epithelial debridement ( about 9 mm diameter) and the contralateral eye with customized debridement ( approximately 1 mm single horizontal scratch ). One month postoperatively, patients had AS-OCT imaging to detect and measure the depth of DL. Results: Patients’ age mean was 25.17 years +/- 4.81 SD . Epithelial healing completed with in 3-7 days in conventional treatment group and demarcation line was evident in 16 eyes ( 89% ) with a mean depth of 290.31 micro m while in customized epi-off treatment group, the epithelial healing lasted less than 24 hours and DL was detectable in 10 patients ( 55.5 % ) with a mean DL depth of 221 micro m with a statistically significant difference ( p < 0.05 ) Subjective postoperative pain graded as “moderate to severe” in about 77% of eyes underwent 9 mm epi-off CXL compared with 55% of those with customized treatment. Conclusions: Although the DL if found in majority cases, but the shallow location in customized corneal debridement cases questioned the efficacy of this technique despite the quick re-epithelialization and less postoperative pain that accompanied it.

Identification of prime factors of active river bank erosion in the lower course of Ganga Bhagirathi River: a study

The present study aims to identify prime factors of active and continuous riverbank erosion. Field visits were conducted from 2015 to 2019. To fulfil the objective of the study, 21 study units prone to bank erosion were selected along the banks of Ganga-Bhagirathi at Jangipur sub-division. Remote sensing and geographic information system were used to measure the area under erosion and deposition from the 1985 to 2015 at five-year intervals. Bank height, bank angle, length of fracture from bank line, river velocity, and channel depth were measured for each study unit using different instruments like cup-type water current meter, clinometers, and measuring tape. Soil samples were collected for textural analysis. Factor analysis was performed to find out prime responsible factors for active riverbank erosion. The result of the study shows that bank height, bank angle, channel width, and fracture length together comprise the first component, which explains 29.48 percent of variance. Riverbank erosion happens due to physical and manmade factors in the lower plain area of the Ganga-Bhagirathi River.

The GAPS Programme at TNG

Aims. We present a novel method for studying the thermal emission of exoplanets as a function of orbital phase at very high spectral resolution, and use it to investigate the climate of the ultra-hot Jupiter KELT-9b. Methods. We combine three nights of HARPS-N and two nights of CARMENES optical spectra, covering orbital phases between quadratures (0.25 &lt; φ &lt; 0.75), when the planet shows its day-side hemisphere with different geometries. We co-add the signal of thousands of Fe I lines through cross-correlation, which we map to a likelihood function. We investigate the phase-dependence of two separate observable quantities, namely (i) the line depths of Fe I and (ii) their Doppler shifts, introducing a new method that exploits the very high spectral resolution of our observations. Results. We confirm a previous detection of Fe I emission, and demonstrate a precision of 0.5 km s−1 on the orbital properties of KELT-9b when combining all nights of observations. By studying the phase-resolved Doppler shift of Fe I lines, we detect an anomaly in the planet's orbital radial velocity well-fitted with a slightly eccentric orbital solution (e = 0.016 ± 0.003, ω = 150−11+13°, 5σ preference). However, we argue that this anomaly is caused by atmospheric circulation patterns, and can be explained if neutral iron gas is advected by day-to-night atmospheric wind flows of the order of a few km s−1. We additionally show that the Fe I emission line depths are symmetric around the substellar point within 10° (2σ), possibly indicating the lack of a large hot-spot offset at the altitude probed by neutral iron emission lines. Finally, we do not obtain a significant preference for models with a strong phase-dependence of the Fe I emission line strength. We show that these results are qualitatively compatible with predictions from general circulation models (GCMs) for ultra-hot Jupiter planets. Conclusions. Very high-resolution spectroscopy phase curves are of sufficient sensitivity to reveal a phase dependence in both the line depths and their Doppler shifts throughout the orbit. They constitute an under-exploited treasure trove of information that is highly complementary to space-based phase curves obtained with HST and JWST, and open a new window onto the still poorly understood climate and atmospheric structure of the hottest planets known to date.

N-bearing complex organics toward high-mass protostars

Context. Complex organic species are known to be abundant toward low- and high-mass protostars. No statistical study of these species toward a large sample of high-mass protostars with the Atacama Large Millimeter/submillimeter Array (ALMA) has been carried out so far. Aims. We aim to study six N-bearing species: methyl cyanide (CH3CN), isocyanic acid (HNCO), formamide (NH2CHO), ethyl cyanide (C2H5CN), vinyl cyanide (C2H3CN) and methylamine (CH3NH2) in a large sample of line-rich high-mass protostars. Methods. From the ALMA Evolutionary study of High Mass Protocluster Formation in the Galaxy survey, 37 of the most line-rich hot molecular cores with ~1" angular resolution are selected. Next, we fit their spectra and find column densities and excitation temperatures of the N-bearing species mentioned above, in addition to methanol (CH3OH) to be used as a reference species. Finally, we compare our column densities with those in other low- and high-mass protostars. Results. CH3OH, CH3CN and HNCO are detected in all sources in our sample, whereas C2H3CN and CH3NH2 are (tentatively) detected in ~78 and ~32% of the sources. We find three groups of species when comparing their excitation temperatures: hot (NH2CHO; Tex ≳ 250 K), warm (C2H3CN, HN13CO and CH313CN; 100 K ≲ Tex ≲ 250 K) and cold species (CH3OH and CH3NH2; Tex ≲ 100 K). This temperature segregation reflects the trend seen in the sublimation temperature of these molecules and validates the idea that complex organic emission shows an onion-like structure around protostars. Moreover, the molecules studied here show constant column density ratios across low- and high-mass protostars with scatter less than a factor ~3 around the mean. Conclusions. The constant column density ratios point to a common formation environment of complex organics or their precursors, most likely in the pre-stellar ices. The scatter around the mean of the ratios, although small, varies depending on the species considered. This spread can either have a physical origin (source structure, line or dust optical depth) or a chemical one. Formamide is most prone to the physical effects as it is tracing the closest regions to the protostars, whereas such effects are small for other species. Assuming that all molecules form in the pre-stellar ices, the scatter variations could be explained by differences in lifetimes or physical conditions of the pre-stellar clouds. If the pre-stellar lifetimes are the main factor, they should be similar for low- and high-mass protostars (within factors ~2–3).

Trueness of intraoral scanners according to subgingival depth of abutment for fixed prosthesis

This study aimed to compare the trueness of intraoral scanners (IOSs) according to the subgingival finish line depth of tooth preparation for fixed prostheses. The prepared maxillary right first molar was fabricated by using ceramic material. A computer-aided design (CAD) reference model (CRM) of the abutment was obtained by using a contact scanner. The subgingival finish line was located according to the depth at 0-mm, 0.25-mm, 0.5-mm, 0.75-mm, and 1-mm. CAD test models (CTMs) were obtained by using 2 IOSs (i500 and CS3600). CRM and CTM were superimposed and analyzed (Geomagic control X). The one-way analysis of variance (ANOVA) was used to compare the trueness according to the subgingival finish line depth. The paired t test was used to compare the trueness of IOSs with and without gingival retraction (α = .05). When the gingival displacement code was not used, it was observed that the trueness of both IOSs decreased significantly as the depth of the subgingival finish line increased (P < 0.001). When the subgingival finish line was positioned deeper than 0.5-mm, the trueness of both IOSs exceeded 100 µm in the marginal region. When the gingival displacement cord was used, the trueness of both IOSs did not exceed 100 µm regardless of the subgingival finish line depth. When gingival cord was used, it showed significantly higher trueness than when not used (P < 0.001). When the gingival displacement cord was not used, the trueness of IOSs decreased as the subgingival finish line depth increased. But the use of the gingival displacement cord improved the scanning trueness by 90%. Thus, it is necessary to use the gingival displacement cord according to the clinical situation to improve scan trueness at the subgingival finish line.

An Interpretable Machine-learning Framework for Modeling High-resolution Spectroscopic Data* * Open-source code at https://github.com/gully/blase.

Comparison of échelle spectra to synthetic models has become a computational statistics challenge, with over 10,000 individual spectral lines affecting a typical cool star échelle spectrum. Telluric artifacts, imperfect line lists, inexact continuum placement, and inflexible models frustrate the scientific promise of these information-rich data sets. Here we debut an interpretable machine-learning framework blasé that addresses these and other challenges. The semiempirical approach can be viewed as “transfer learning”—first pretraining models on noise-free precomputed synthetic spectral models, then learning the corrections to line depths and widths from whole-spectrum fitting to an observed spectrum. The auto-differentiable model employs back-propagation, the fundamental algorithm empowering modern deep learning and neural networks. Here, however, the 40,000+ parameters symbolize physically interpretable line profile properties such as amplitude, width, location, and shape, plus radial velocity and rotational broadening. This hybrid data-/model-driven framework allows joint modeling of stellar and telluric lines simultaneously, a potentially transformative step forward for mitigating the deleterious telluric contamination in the near-infrared. The blasé approach acts as both a deconvolution tool and semiempirical model. The general-purpose scaffolding may be extensible to many scientific applications, including precision radial velocities, Doppler imaging, chemical abundances for Galactic archeology, line veiling, magnetic fields, and remote sensing. Its sparse-matrix architecture and GPU acceleration make blasé fast. The open-source PyTorch-based code blase includes tutorials, Application Programming Interface documentation, and more. We show how the tool fits into the existing Python spectroscopy ecosystem, demonstrate a range of astrophysical applications, and discuss limitations and future extensions.