Line Of Convergence Research Articles

Increasing precision during neuromodulator injections for frontal rhytids-Using ultrasound imaging to identify the line of convergence.

Recent research introduced the concept of the "line of convergence" as a guide for injectors to enhance precision and avoid complications when treating the frontalis muscle with toxins. However, currently, no pre-injection ultrasound scanning is employed to increase precision and reduce adverse events when searching for the line of convergence. To explore the feasibility and practicality of implementing pre-injection ultrasound scanning into aesthetic neuromodulator treatments of the forehead. The sample of this study consisted of n = 55 volunteers (42 females and 13 males), with a mean age of 42.24 (10.3) years and a mean BMI of 25.07 (4.0) kg/m2. High-frequency ultrasound imaging was utilized to measure the thickness, length, and contractility of the frontal soft tissue and to determine the precise location of the line of convergence during maximal frontalis muscle contraction. The results revealed that the line of convergence was located at 58.43% (8.7) of the total forehead height above the superior border of the eyebrow cilia without a statistically significant difference between sex, age, or BMI. With frontalis muscle contraction, the forehead shortens in males by 25.90% (6.5), whereas in females it shortens only by 21.74% (5.1), with p < 0.001 for sex differences. This study demonstrated the feasibility and practicality of pre-injection ultrasound scanning for facial aesthetic neuromodulator treatments. Knowing the location of the line of convergence, injectors can determine precisely and on an individual basis where to administer the neuromodulator deep or superficial or when the injection location is at risk to cause eyebrow ptosis.

Mesoscale structures in the Orinoco basin during an extreme precipitation event in the tropical Andes

During the night of March 31st, 2017, a severe precipitation event affected the city of Mocoa, in the tropical Andes. Total 24-h accumulated precipitation during that day was the fourth largest on record. Satellite data shows that the event was associated with a Mesoscale Convective System (MCS) that formed over the Amazon and moved westward, reaching the tropical Andes. Reanalysis data suggests that a rapid intensification of the Orinoco Low-Level Jet (OLLJ) traveling southwestward parallel to the Andes was a precursor that favored the zones of convergence for MCS formation. Upstream intensification of the OLLJ was evident 8 h prior to the Mocoa precipitation event. Given the lack of a dense network of observations in this understudied region, we use the Weather Research and Forecasting model (WRF) to explore the plausible mesoscale structures in the OLLJ region associated with the initiation and development of the MCS. We study an ensemble of simulations with different grid spacings (12, 4 and 1.3 km) and Planetary Boundary Layer (PBL) schemes (YSU, MYNN and QNSE). The more realistic MCSs were obtained with the QNSE and YSU schemes, given that the corresponding simulations included a density current in the lowest levels moving parallel to the Andes, with a sharp line of convergence and large vertical velocities over the leading edge of the mesoscale disturbance. In contrast, the MYNN scheme produced a weaker OLLJ and no density current. It is suggested that the stronger vertical mixing in the MYNN scheme was associated with the vertical dilution of the OLLJ, and with a much weaker low-level traveling perturbation via the upward radiation of energy by gravity waves. Our results help to better understand flood-producing extreme events over the poorly studied Andes-Amazon region and provide the groundwork for improved predictability of such storms.

The Platysma Contraction Pattern in Healthy Adults: A Vector Analysis Study.

The platysma muscle's role in lower face dynamics is complex. Multiple insertion points to soft-tissue structures at various levels in the lower face create a multifaceted contraction pattern. To avoid adverse effects in cosmetic procedures when targeting the platysma, its anatomy and physiology must be understood. Clinical observations hint at a bidirectional contraction pattern. Eighteen healthy volunteers (13 women and five men) with a mean age of 44.2 ± 10.1 years were enrolled. Skin displacement vector analysis was used on maximal platysma contraction to characterize and calculate the movement of the neck and lower face skin. In all of the participants, a bidirectional movement of the skin was observed: the skin of the lower face and inferior to the jawline moved caudally, whereas the skin of the lower neck moved cephalad. Both movements converged at a line situated at 54% ± 10% and 55% ± 8% of the length between the clavicle and the inferior base of the ear lobe in men and women, respectively ( P = 0.70). The platysma is a bidirectional muscle with a line of convergence. Whereas the superior portion acts as lip depressor, the lower portion elevates the skin of the upper chest and lower neck. This transition can explain some of the clinically observed adverse effects of neuromodulation of the neck area. It can potentially direct neuromodulation injections to focus above the convergence line to better address lower face descent.

Locking the line of convergence by botulinum toxin type A for the treatment of dynamic forehead wrinkles.

Treatment of horizontal forehead lines with botulium toxin type A is a common procedure that helps achieve a youthful and rejuvenated look. Adequate knowledge of the anatomy and an individualized treatment approach is the key to successful treatment outcome. To evaluate the cosmetic outcome following treatment of dynamic forehead wrinkles by locking the line of convergence using botulinum toxin type A. Fifty female patients with dynamic forehead wrinkles were included. The line of convergence was identified, and injection points were determined. Patients received injections of botulinum toxin type A in the upper part of the frontalis along the line of convergence. Patients were evaluated before injection and the response was evaluated after 2 weeks and after 3 months of injection. Post-treatment significant decrease in dynamic wrinkle scale was detected. The distance between the medial and lateral canthi and theircorresponding lower brow margins on maximum brow elevation was also significantly decreased after treatment. Meanwhile, the validated brow positioning score revealed no significant change in the resting brow position when pre-and post-treatment scores were compared. Treating forehead wrinkles by injecting botulinum toxin along the line of convergence is an effective technique that requires less overall amount of toxin, improves the appearance of the wrinkles and minimizes the risk of development of side effects.

Entrepreneurial self-efficacy and a student's predisposition to choose an entrepreneurial career path: the role of self-perceived employability

PurposeThe purpose of this paper is to examine how entrepreneurial self-efficacy (ESE) and self-perceived employability (SPE) affect students' choice of an entrepreneurial career path.Design/methodology/approachA survey approach was used to gather data from 274 final year undergraduate students at a South African university. The study made use of partial least squares (PLS) structural equation model (SEM) analyses to test the hypothesized associations.FindingsESE was positively associated with the intention to engage in both a full-time and a hybrid entrepreneurial career path. Also, SPE was positively associated with the intention to engage in hybrid entrepreneurship but negatively associated with engaging in full-time entrepreneurship. Additionally, the effect of ESE on the intention to engage in hybrid entrepreneurship was significantly moderated by SPE, such that the effect was more pronounced for students with a high SPE.Research limitations/implicationsData were gathered only from one South African university and as such there is a need for similar studies to improve the generalizability of the findings. Also, the measures for ESE and SPE used in the present study are not the only ones available. Thus, future studies are encouraged to use alternative measures to further assess the robustness of the proposed associations.Originality/valueThe arguments and the subsequent findings of this study indicate a new line of convergence for the popular but disjointed literature on ESE and SPE.

Sea-land breeze diurnal component and its interaction with a cold front on the coast of Sisal, Yucatan: A case study

The breeze phenomenon is of great importance in coasts around the world owing to both its impact on local atmospheric dynamics and its influence on coastal processes. The northwest of the Yucatan Peninsula (YP) is characterized by the presence of intense sea breezes and Cold Surge (CS) events (locally known as Nortes). Field observations suggest that nearshore hydrodynamics and beach evolution in the study area are strongly controlled by waves generated during sea breeze events. In this paper, the diurnal wind component associated with the breeze phenomenon and its variability due to the presence of a CS event are investigated utilizing the Weather Research and Forecasting (WRF) model. The WRF model is implemented in three nested domains with a maximum resolution of 3.6-km. The numerical model was validated with observations at 20 stations located across the YP, adequately reproducing wind speed and direction at Sisal, Yuc. coast, with a correlation coefficient of 0.56 and a circular correlation coefficient of 0.83, respectively. Diurnal wind components were least-squares fitted to a sinusoidal signal, and the resulting parameters were used to obtain an elliptical hodograph related to the breeze phenomenon. Numerical results suggest that sea breezes, with wind intensities higher than 10 ms−1, extend more than 100 km offshore in the northern YP. Although breeze events are caused by differential heating at a small spatial scale, particularly in the Gulf of Mexico, this diurnal signal exceeds the local spatial scale. Furthermore, the interaction between the sea breeze and the mean wind associated to the trade winds generates a line of convergence that crosses the YP. Model results allow us to identify that the mechanisms responsible of such large amplitude of the diurnal signal in this area are: (i) the thermal gradient, (ii) the relatively small value of the Coriolis force, (iii) the orography, (iv) the friction, and (v) the peninsula's geometry. The numerical results revealed that during the interaction between local breezes and a CS event, the diurnal signal remains, except for the initial day of the event. However, further research is needed to generalize the current results for other CS events with different intensity and displacement characteristics.

The Bidirectional Movement of the Frontalis Muscle: Introducing the Line of Convergence and Its Potential Clinical Relevance.

Cosmetic treatment of the forehead using neuromodulators is challenging. To avoid adverse events, the underlying anatomy has to be understood and thoughtfully targeted. Clinical observations indicate that eyebrow ptosis can be avoided if neuromodulators are injected in the upper forehead, despite the frontalis muscle being the primary elevator. Twenty-seven healthy volunteers (11 men and 16 women) with a mean age of 37.5 ± 13.7 years (range, 22 to 73 years) and of diverse ethnicity (14 Caucasians, four African Americans, three Asians, and six of Middle Eastern descent) were enrolled. Skin displacement vector analyses were conducted on maximal frontalis muscle contraction to calculate magnitude and direction of forehead skin movement. In 100 percent of investigated volunteers, a bidirectional movement of the forehead skin was observed: the skin of the lower forehead moved cranially, whereas the skin of the upper forehead moved caudally. Both movements converged at a horizontal forehead line termed the line of convergence, or C-line. The position of the C-line relative to the total height of the forehead was 60.9 ± 10.2 percent in men and 60.6 ± 9.6 percent in women (p = 0.941). Independent of sex, the C-line was located at the second horizontal forehead line when counting from superior to inferior (men, n = 2; women, n = 2). No difference across ethnicities was detected. The identification of the C-line may potentially guide practitioners toward more predictable outcomes for forehead neuromodulator injections. Injections above the C-line could mitigate the risk of neuromodulator-induced brow ptosis.

Convection Initiation Aided by Lake-Breeze Convergence over the Niagara Peninsula

AbstractObservations from the 2015 Environment and Climate Change Canada Pan/Parapan American Science Showcase (ECPASS) and real-case, cloud-resolving numerical simulations with the Weather Research and Forecasting (WRF) Model are used to investigate two cases of moist convection forced by lake-breeze convergence over southern Ontario (18 July and 15 August 2015). The two cases shared several characteristics, including high pressure conditions, similar morning soundings, and isolated afternoon convection along a line of lake-breeze convergence between Lakes Erie and Ontario. However, the convection was significantly stronger in the August case, with robustly deeper clouds and larger radar reflectivities than in the July case. Synoptic and mesoscale analyses of these events reveal that the key difference between them was their large-scale forcing. The July event exhibited a combination of strong warm advection and large-scale descent at midlevels (850–650 hPa), which created an inversion layer that capped cloud tops at 4–6 km. The August case exhibited similar features (large-scale descent and warm advection), but these were focused at higher levels (700–400 hPa) and weaker. As a consequence, the convection in the August case was less suppressed at midlevels and ascended deeper (reaching over 8 km). Although the subcloud updraft along the lake-breeze convergence zone was also found to be stronger in the August case, this difference was found to be an effect, rather than a cause, of stronger moist convection within the cloud layer.

A numerical study of the thermal bar in shallow water during the autumn cooling

The article presents numerical simulation of the autumnal thermal bar dynamics on the example of the Selenga River shallow water in Lake Baikal. Hydrophysical and atmospheric conditions of the object under study in autumn are taken into account. The influence of river inflow (runoff current and water mineralization) and wind impact on the thermal bar behavior are evaluated. The numerical modeling analysis demonstrates that in the early stage of the thermal bar development, the most significant for convection is the momentum of the river inflow. However, with the distance increase between the thermal bar and the river mouth, the role of the river mineralization and wind stress also increases. Highly mineralized inflow waters have the largest impact on thermohydrodynamic processes in shallow waters under calm weather conditions. Wind action on the lake surface may lead to the deviation of the line of convergence of water masses from to the 4 °C isotherm. Moreover, prolonged wind activity may result in the destruction of the thermal bar front and vertical thermal homogeneity across the entire shallow water area.

On the Zeros of Euler Product Dirichlet Functions

We study a class of Dirichlet functions obtained as analytic continuation across the line of convergence of Dirichlet series which can be written as Euler products. This class includes that of Dirichlet L-functions. The problem of the existence of multiple zeros for this last class is outstanding. It is tacitly accepted, yet not proved that the Riemann Zeta function, which belongs to this class, does not possess multiple zeros. In a previous study we provided an example of Dirichlet function having double zeros, but that function is not an Euler product function. In this paper we deal with Euler product functions and by using the geometric properties of the mapping realized by these functions, we tackle the problem of the multiplicity of their zeros.

Performance analysis of three-dimensional differential geometric guidance law against low-speed maneuvering targets

The performance of the three-dimensional differential geometric guidance law with proportional navigation formation against a target maneuvering arbitrarily with time-varying normal acceleration is thoroughly analyzed using the Lyapunov-like approach. The validation of this guidance law is firstly proved, and then the performance issues such as capturability, heading error control efficiency, line of sight rate convergence, and commanded acceleration requirement are analyzed, under the condition that the missile is initially flying toward the target with a speed advantage. It is proved that an intercept can occur and the line of sight rate and missile commanded acceleration can be limited in certain ranges, if the initial heading error is small and the navigation gain is sufficiently large. The nonlinear relative dynamics between the missile and the target is taken into full account, and the analysis process is simple and intuitive, due to the use of a convenient line of sight rotating coordinate system. Finally, the new theoretical findings are validated by numerical simulations.

Effects of Explicit Urban-Canopy Representation on Local Circulations Above a Tropical Mega-City

The Advanced Regional Prediction System (ARPS) is coupled with the tropical town energy budget (tTEB) scheme to analyze the effects of the urban canopy circulation over the metropolitan area of Sao Paulo and its interactions with the sea breeze and mountain-valley circulation in the eastern state of Sao Paulo, Brazil. Two experiments are carried out for the typical sea-breeze event occurring on 22 August 2014 under weak synoptic forcing and clear-sky conditions: (a) a control run with the default semi-desert surface parametrization and; (b) a tTEB run for the urban canopy of Sao Paulo. A realistic land-use database over the south-eastern domain of Brazil is used in the downscaling simulation to a horizontal grid resolution of 3 km. Our results indicate that ARPS effectively simulates features of the nighttime and early morning land-breeze circulation, which is affected by the surrounding hills and the nocturnal heat island of Sao Paulo. By early afternoon, the south-eastern sea-breeze circulation moves inland perpendicular to the upslope of the Serra do Mar scarp, which generates a line of moisture convergence and updrafts further inland. Later, the convergence line reaches Sao Paulo and interacts with the circulation arising from the urban heat island (UHI), which increases the moisture convergence and strength of updrafts. The surface energy balance indicates that the UHI is caused by large sensible heat storage within the urban canopy during the day, which is later released in the afternoon and at night. The simulations are verified with available radiosonde and surface weather station data, land-surface-temperature estimates from the moderate resolution imaging spectroradiometer, as well as the National Center for Atmospheric Research reanalysis databases. The three-dimensional geometry of the urban canyons within the tTEB scheme consistently improves the thermodynamically-induced circulation over Sao Paulo.

Zeta functions and complex dimensions of relative fractal drums: theory, examples and applications

In 2009, the first author introduced a new class of zeta functions, called `distance zeta functions', associated with arbitrary compact fractal subsets of Euclidean spaces of arbitrary dimension. It represents a natural, but nontrivial extension of the theory of `geometric zeta functions' of bounded fractal strings. In this memoir, we introduce the class of `relative fractal drums' (or RFDs), which contains the classes of bounded fractal strings and of compact fractal subsets of Euclidean spaces as special cases. Furthermore, the associated (relative) distance zeta functions of RFDs, extend (in a suitable sense) the aforementioned classes of fractal zeta functions. This notion is very general and flexible, enabling us to view practically all of the previously studied aspects of the theory of fractal zeta functions from a unified perspective as well as to go well beyond the previous theory. The abscissa of (absolute) convergence of any relative fractal drum is equal to the relative box dimension of the RFD. We pay particular attention to the question of constructing meromorphic extensions of the distance zeta functions of RFDs, as well as to the construction of transcendentally $\infty$-quasiperiodic RFDs (i.e., roughly, RFDs with infinitely many quasiperiods, all of which are algebraically independent). We also describe a class of RFDs (and, in particular, a new class of bounded sets), called {\em maximal hyperfractals}, such that the critical line of (absolute) convergence consists solely of nonremovable singularities of the associated relative distance zeta functions. Finally, we also describe a class of Minkowski measurable RFDs which possess an infinite sequence of complex dimensions of arbitrary multiplicity $m\ge1$, and even an infinite sequence of essential singularities along the critical line.

On the turbulent flow structure around an instream structure with realistic geometry

We investigate the flow dynamics around a rock vane, a widely-used instream structure for stream restoration, by conducting laboratory flume experiments, and carrying out high-resolution Large Eddy Simulation (LES) taking advantage of parallel computing. The flume experiments are conducted under fixed- and mobile-bed conditions, where the velocities and bed elevations are measured, respectively. The LES is carried out for the fixed-bed experiment by directly resolving the details of the rocks that constitute the vane and the individual roughness elements on the channel bed. The LES-computed mean flow statistics show good agreement with the measurements, and the analysis of the computed flow field reveals the existence of two counter-rotating secondary flow cells downstream of the vane, which originate from the plunging of the three-dimensional streamlines onto a lower part of the sidewall downstream of the vane. To further examine the role of the secondary flow cells under a mobile-bed condition, the LES results are compared with the equilibrium bed elevation measured in the mobile bed experiment. The mobile-bed experiment reveals the existence of an oblique sand ridge downstream of the vane that is aligned with the line of flow convergence caused by the collision of the two secondary flow cells. The results indicate that the two counter-rotating cells downstream of the rock vane has a profound impact on the mean flow and bed shear stress as well as on the bed morphodynamics. This article is protected by copyright. All rights reserved.

IN-SYNC. III. THE DYNAMICAL STATE OF IC 348—A SUPER-VIRIAL VELOCITY DISPERSION AND A PUZZLING SIGN OF CONVERGENCE

Most field stars will have encountered the highest stellar density and hence the largest number of interactions in their birth environment. Yet the stellar dynamics during this crucial phase are poorly understood. Here we analyze the radial velocities measured for 152 out of 380 observed stars in the 2?6 Myr old star cluster IC 348 as part of the SDSS-III APOGEE. The radial velocity distribution of these stars is fitted with one or two Gaussians, convolved with the measurement uncertainties including binary orbital motions. Including a second Gaussian improves the fit; the high-velocity outliers that are best fit by this second component may either (1) be contaminants from the nearby Perseus OB2 association, (2) be a halo of ejected or dispersing stars from IC 348, or (3) reflect that IC 348 has not relaxed to a Gaussian velocity distribution. We measure a velocity dispersion for IC 348 of 0.72 ? 0.07 km s?1 (or 0.64 ? 0.08 km s?1 if two Gaussians are fitted), which implies a supervirial state, unless the gas contributes more to the gravitational potential than expected. No evidence is found for a dependence of this velocity dispersion on distance from the cluster center or stellar mass. We also find that stars with lower extinction (in the front of the cloud) tend to be redshifted compared with stars with somewhat higher extinction (toward the back of the cloud). This data suggest that the stars in IC 348 are converging along the line of sight. We show that this correlation between radial velocity and extinction is unlikely to be spuriously caused by the small cluster rotation of 0.024 ? 0.013 km s?1 arcmin?1 or by correlations between the radial velocities of neighboring stars. This signature, if confirmed, will be the first detection of line of sight convergence in a star cluster. Possible scenarios for reconciling this convergence with IC 348's observed supervirial state include: (a) the cluster is fluctuating around a new virial equilibrium after a recent disruption due to gas expulsion or a merger event, or (b) the population we identify as IC 348 results from the chance alignment of two sub-clusters converging along the line of sight. Additional measurements of tangential and radial velocities in IC 348 will be important for clarifying the dynamics of this region and informing models of the formation and evolution of star clusters. The radial velocities analyzed in this paper have been made available online.

Shock wave convergence in water with parabolic wall boundaries

The convergence of shock waves in water, where the cross section of the boundaries between which the shock wave propagates is either straight or parabolic, was studied. The shock wave was generated by underwater electrical explosions of planar Cu wire arrays using a high-current generator with a peak output current of ∼45 kA and rise time of ∼80 ns. The boundaries of the walls between which the shock wave propagates were symmetric along the z axis, which is defined by the direction of the exploding wires. It was shown that with walls having a parabolic cross section, the shock waves converge faster and the pressure in the vicinity of the line of convergence, calculated by two-dimensional hydrodynamic simulations coupled with the equations of state of water and copper, is also larger.

IMPROVING THE PRECISION OF TIME-DELAY COSMOGRAPHY WITH OBSERVATIONS OF GALAXIES ALONG THE LINE OF SIGHT

In order to use strong gravitational lens time delays to measure precise and accurate cosmological parameters the effects of mass along the line of sight must be taken into account. We present a method to achieve this by constraining the probability distribution function of the effective line of sight convergence k_ext. The method is based on matching the observed overdensity in the weighted number of galaxies to that found in mock catalogs with k_ext obtained by ray-tracing through structure formation simulations. We explore weighting schemes based on projected distance, mass, luminosity, and redshift. This additional information reduces the uncertainty of k_ext from sigma_k $0.06 to ~0.04 for very overdense lines of sight like that of the system B1608+656. For more common lines of sight, sigma_k is reduced to ~<0.03, corresponding to an uncertainty of ~<3% on distance. This uncertainty has comparable effects on cosmological parameters to that arising from the mass model of the deflector and its immediate environment. Photometric redshifts based on g, r, i and K photometries are sufficient to constrain k_ext almost as well as with spectroscopic redshifts. As an illustration, we apply our method to the system B1608+656. Our most reliable k_ext estimator gives sigma_k=0.047 down from 0.065 using only galaxy counts. Although deeper multi-band observations of the field of B1608+656 are necessary to obtain a more precise estimate, we conclude that griK photometry, in addition to spectroscopy to characterize the immediate environment, is an effective way to increase the precision of time-delay cosmography.

Knowledge-based automatic generation of 3D building models from building footprint by straight skeleton computation

3D urban models are important in several fields, such as urban planning and gaming industries. However, enormous time and labour has to be consumed to create these 3D models. In order to automate laborious steps, a GIS and CG integrated system was proposed for automatically generating 3D building models, based on building polygons (building footprints) on digital maps. For either orthogonal or non-orthogonal building polygons, the knowledge-based system is proposed for automatically generating 3D building models with general shaped roofs by straight skeleton computation. In this paper, the algorithm for 'split event' is clarified and the new methodology is presented for constructing roof models by assuming the third event: 'simultaneous event' and, at the end of the shrinking process, some polygons are converged to 'a line of convergence'.

VHF radar observations of surface currents off the northern Opal coast in the eastern English Channel

Two very high-frequency radars (VHFR) operating on the Opal coast of eastern English Channel provided a nearly continuous 35-day long dataset of surface currents over a 500 km 2 area at 0.6–1.8 km resolution. Argo drifter tracking and CTD soundings complemented the VHFR observations, which extended approximately 25 km offshore. The radar data resolve three basic modes of the surface velocity variation in the area, that are driven by tides, winds and freshwater fluxes associated with seasonal river discharge. The first mode, accounting for 90% of variability, is characterized by an along-shore flow pattern, whereas the second and third modes exhibit cross-shore, and eddy-like structures in the current velocity field. All the three modes show the dominant semi-diurnal variability and low-frequency modulation by the neap-spring tidal cycle. Although tidal forcing provides the major contribution to variability of local currents, baroclinicity plays an important role in shaping the 3D velocity field averaged over the tidal cycle and may strongly affect tracer dynamics on larger time scales. An empirical orthogonal function (EOF) decomposition and a spectral rotary analysis of the VHFR data reveal a discontinuity in the velocity field occurring approximately 10 km offshore which was caused by the reversal in the sign of rotation of the current vector. This feature of local circulation is responsible for surface current convergence on ebb, divergence on flood and strong oscillatory vertical motion. Spectral analysis of the observed currents and the results of the Agro drifter tracking indicate that the line of convergence approximately follows the 30-m isobath. The most pronounced feature of the radar-derived residual circulation is the along-coast intensification of surface currents with velocity magnitude of 0.25 m/s typical for the Regions of Freshwater Influence (ROFI). The analysis has provided a useful, exploratory examination of surface currents, suggesting that the circulation off the Opal coast is governed by ROFI dynamics on the hypertidal background.

Natural boundary of random Dirichlet series

For the random Dirichlet series $$\sum\limits_{n = 0}^\infty {X_n (\omega )e^{ - s\lambda _n } } (s = \sigma + it \in \mathbb{C}, 0 = \lambda _0 < \lambda _n \uparrow \infty )$$ whose coefficients are uniformly nondegenerate independent random variables, we provide some explicit conditions for the line of convergence to be its natural boundary a.s.