Moderate Inclination Research Articles

Brass wire ligation for treatment of the ectopic eruption of the mandibular second molar: a case report.

Ectopic eruption of the second permanent molar is a tooth replacement disorder during adolescence. If not treated in time, it can cause hard tissue of the adjacent first molar resorption, early tooth loss, decreased chewing efficiency, and other serious malocclusions. Timely detection and treatment of ectopic eruption of the second permanent molar are of great significance in preventing malocclusions in adolescents and establishing normal occlusion relationships. However, current case reports on the ectopic eruption of the mandibular second molar are relatively rare and are mostly concentrated on surgical and orthodontic treatments, and long-term follow-up is lacking. This paper reports a case in which brass wire ligation was used to treat ectopic eruption of the mandibular second permanent molar, allowing the permanent teeth to erupt smoothly and establish a normal occlusion. The patient was observed for five years after the operation. The occlusion was stable, and the tooth root development, pulp vitality, and periodontal conditions were normal. This paper provides a clinical approach that is short in treatment duration, simple, and minimally invasive for young mandibular second permanent molars with moderate mesial inclination and partial eruption. This method is of importance in helping children establish physiological occlusion.

Resolving the vicinity of supermassive black holes with gravitational microlensing

ABSTRACT Upcoming wide-field surveys will discover thousands of new strongly lensed quasars which will be monitored with unprecedented cadence by the Legacy Survey of Space and Time (LSST). Many of these quasars will undergo caustic-crossing events over the 10-yr LSST survey, during which the quasar’s inner accretion disc crosses a caustic feature produced by an ensemble of microlenses. Such caustic-crossing events offer the unique opportunity to probe the vicinity of the central supermassive black hole, especially when combined with high cadence, multi-instrument follow-up triggered by LSST monitoring. To simulate the high-cadence optical monitoring of caustic-crossing events, we use relativistic accretion disc models which leads to strong asymmetric features. We develop analysis methods to measure the innermost stable circular orbit (ISCO) crossing time of isolated caustic-crossing events and benchmark their performance on our simulations. We also use our simulations to train a convolutional neural network (CNN) to infer the black hole mass, inclination angle, and impact angle directly from these light curves. As a pilot application of our methods, we used archival caustic-crossings of QSO 2237+0305 to estimate the black hole mass and inclination angle. From these data, two of these methods called the second derivative and wavelet methods measure an ISCO crossing time of 48.5 and 49.5 d, corresponding to a Kerr black hole mass of MBH = (1.5 ± 1.2) × 109 and (1.5 ± 1.3) × 109 M⊙, respectively. The CNN inferred log10(MBH/M⊙) = 8.35 ± 0.30 when trained on Schwarzschild black hole simulations, and a moderate inclination of i = 45 ± 23°. These measurements are found to be consistent with previous estimates.

THE EFFECT OF BUY NOW, PAY LATER FINTECH ON TRADITIONAL FINANCIAL SERVICES AND CONSUMER BEHAVIOR IN SAUDI ARABIA

This research investigates the impacts of financial technology (Fintech) on traditional financial services and the emergence of Buy Now Pay Later (BNPL) companies within the Kingdom of Saudi Arabia. Fintech signifies a paradigmatic shift in the financial landscape, utilizing technology to transform banking, payment systems, investment strategies, and lending practices. The BNPL model, recognized for its disruptive nature, enables consumers to divide purchases into interest-free installments, thereby reshaping global consumer spending patterns. This study concentrates specifically on the Saudi Arabian context, where Fintech adoption is experiencing rapid growth. It scrutinizes the factors that influence BNPL adoption behavior among Saudi consumers, addressing a research void in localized studies. A sample of 100 consumer participants responded to an online survey. The statistical analysis underscores the strength, significance, and correlation between financial elements and the factors crucial to the decision-making process for BNPL adoption. The descriptive analysis of Independent Variables (IVs) encompassing Performance Expectancy (PE), Effort Expectancy (EE), Social Influence (SI), and Facilitating Conditions (FC) has provided significant insights into the perceptions of consumers regarding the adoption of Buy Now Pay Later (BNPL) services. The analysis has revealed noteworthy patterns in the data. Performance Expectancy (PE) demonstrates moderate perceptions (Mean = 2.98), indicating a measured belief in the usefulness of BNPL. Furthermore, Facilitating Conditions (FC) registered moderate scores (Mean = 3.04), underscoring the significance of favorable external factors. Collectively, these findings depict a moderate inclination and a generally positive outlook among respondents towards BNPL adoption, providing insights into the factors influencing their adoption behaviors. The research findings contribute to academic comprehension, provide insights for industry stakeholders, and inform the development of policies and regulations within Saudi Arabia's dynamic Fintech ecosystem. Future studies may utilize longitudinal studies, conduct cross-cultural comparisons, and explore technological integration in exploring the BNPL consumer behavior studies.

The formation of transiting circumplanetary debris discs from the disruption of satellite systems during planet–planet scattering

Abstract Several stars show deep transits consistent with discs of roughly 1 R⊙ seen at moderate inclinations, likely surrounding planets on eccentric orbits. We show that this configuration arises naturally as a result of planet–planet scattering when the planets possess satellite systems. Planet–planet scattering explains the orbital eccentricities of the discs’ host bodies, while the close encounters during scattering lead to the exchange of satellites between planets and/or their destabilisation. This leads to collisions between satellites and their tidal disruption close to the planet. Both of these events lead to large quantities of debris being produced, which in time will settle into a disc such as those observed. The mass of debris required is comparable to a Ceres-sized satellite. Through N-body simulations of planets with clones of the Galilean satellite system undergoing scattering, we show that 90 % of planets undergoing scattering will possess debris from satellite destruction. Extrapolating to smaller numbers of satellites suggests that tens of percent of such planets should still possess circumplanetary debris discs. The debris trails arising from these events are often tilted at tens of degrees to the planetary orbit, consistent with the inclinations of the observed discs. Disruption of satellite systems during scattering thus simultaneously explains the existence of debris, the tilt of the discs, and the eccentricity of the planets they orbit.

Polarized signatures of orbiting hot spots: Special relativity impact and probe of spacetime curvature

Context. The Galactic Center supermassive black hole is well known to exhibit transient peaks of flux density on a daily basis across the spectrum. Recent infrared and millimeter observations have strengthened the case for the association between these flares and circular orbital motion in the vicinity of the event horizon. The strongly polarized synchrotron radiation associated with these events leads to specific observables called QU loops, that is, looping motion in the Stokes QU plane of linear polarization. These patterns have been observed by the Submillimeter Array, VLTI/GRAVITY, and ALMA. Aims. We want to deepen the understanding of the QU loops associated with orbiting hot spots. To this end, we computed such loops in Minkowski and Schwarzschild spacetimes in order to determine which aspects of the observed patterns are due to special- or general-relativistic phenomena. Methods. We considered a parcel of energized plasma in circular motion in Minkowski spacetime and in Keplerian orbit in the Schwarzschild spacetime. We computed, using the GYOTO ray-tracing code, the polarized radiative transfer associated with this orbiting hot spot and derived the evolution of the flux density, astrometry, and Stokes Q and U parameters. Results. We show that QU loops in Minkowski spacetime at low or moderate inclination i ≲ 45° (where i = 0° is a face-on view) share all the qualitative features of Schwarzschild QU loops. There exist QU loops for all setups considered (including for the face-on view and vertical magnetic field), there may be one or two QU loops per orbital period for a vertical magnetic field configuration, and there are always two QU loops in case of a toroidal magnetic field. The simplicity of Minkowski spacetime is a key asset for allowing us to provide analytical formulas that explain the details of this behavior. Moreover, we analyzed the flux variation of the hot spot and show that it is dictated either by the angular dependence of the radiative transfer coefficients or by relativistic beaming. In the former case, this can lead to extreme flux ratios, even at a moderate inclination. Finally, we highlight the increasing mirror asymmetry of the Schwarzschild QU track with increasing inclination and show that this behavior is a specific Schwarzschild feature caused by light bending. Conclusions. Although special-relativistic effects have not been extensively discussed in this context, they are a crucial part in generating the observed QU loops. However, general-relativistic light bending leads to a specific observable feature encoded in the asymmetry of the observed loops, and this feature might allow the spacetime curvature to be quantified.

Substorm‐Time Ground dB/dt Variations Controlled by Interplanetary Shock Impact Angles: A Statistical Study

AbstractIn this study, we investigate the effects caused by interplanetary (IP) shock impact angles on the subsequent ground dB/dt variations during substorms. IP shock impact angles have been revealed as a major factor controlling the subsequent geomagnetic activity, meaning that shocks with small inclinations with the Sun‐Earth line are more likely to trigger higher geomagnetic activity resulting from nearly symmetric magnetospheric compressions. Such field variations are linked to the generation of geomagnetically induced currents (GICs), which couple to artificial conductors on the ground leading to deleterious consequences. We use a sub‐set of a shock data base with 237 events observed in the solar wind at L1 upstream of the Earth, and large arrays of ground magnetometers at stations located in North America and Greenland. The spherical elementary current system methodology is applied to the geomagnetic field data, and field‐aligned‐like currents in the ionosphere are derived. Then, such currents are inverted back to the ground and dB/dt variations are computed. Geographic maps are built with these field variations as a function of shock impact angles. The main findings of this investigation are: (a) typical dB/dt variations (5–10 nT/s) are caused by shocks with moderate inclinations; (b) the more frontal the shock impact, the more intense and the more spatially defined the ionospheric current amplitudes; and (c) nearly frontal shocks trigger more intense dB/dt variations with larger equatorward latitudinal expansions. Therefore, the findings of this work provide new insights for GIC forecasting focusing on nearly frontal shock impacts on the magnetosphere.

Factors Influencing Prostate Cancer Screening Intentions in Lebanese Men.

The objective of this study is to investigate the perceived obstacles and willingness of Lebanese men aged 40 and above to undergo screening for prostate cancer. A cross-sectional research design was employed. The study utilized a survey questionnaire to collect data on various factors influencing screening behaviors. The research instrument consisted of a comprehensive survey questionnaire that incorporated validated scales to assess barriers to prostate cancer screening, intention to screen, and the International Prostate Symptom Score (IPSS). The study found that the 120 participants had an average IPSS score of 7.20 ± 2.23, most people (70%) had mild symptoms of prostate cancer, whereas others had moderate (20%) or severe symptoms (10%). The majority of the men indicated a low to moderate inclination to undergo screening through Prostate-specific antigen testing, or digital rectal examination (DRE) (PSA), with 76% considering DRE and 70% considering PSA. The main barriers to screening included the dread of receiving distressing outcomes (48%) and a lack of understanding about the screening procedure (54%). The study identified key factors affecting the intention to undergo a prostate cancer screening. Regarding DREs, these factors included the perceived danger of the illness and prior information from doctors about prostate conditions. When it came to the intention to undergo screening through the prostate-specific antigen test (PSA), determinants included the perceived threat of the disease, one's general health perception, and prior information from doctors about prostate-related issues. Additionally, a significant proportion of participants believed that prostate cancer was not a serious illness (56%) and 57% thought DRE was embarrassing. The participants displayed a low willingness to get screened for prostate cancer. Implementing interventions that focus on increasing awareness of the disease and its associated risks could potentially reduce the barriers and boost participation in prostate cancer screening.

Entrepreneurial Attributes of the College Students Towards the Entrepreneurship

This study investigates entrepreneurial attributes, focusing on key elements such as the need for achievement, need for independence, risk-taking behavior, and entrepreneurial motivation, with a specific emphasis on college students and their involvement in entrepreneurship. The primary objective is to analyze the motivational aspects that drive students to embark on entrepreneurial endeavors. To fulfill these objectives, the current research conducted a comprehensive evaluation of the entrepreneurial motivation of students concerning entrepreneurship. The study was carried out at Chaudhary Charan Singh Haryana Agriculture University in Hisar. A systematic and proportional sampling method was employed to select a sample of 200 students, including 100 graduates and 100 postgraduates, who have faced unemployment over the last 3–4 years. It was observed that among the graduate unemployed students, there was a predominant indication of high entrepreneurial motivation (49.0%). Furthermore, they reported a moderate level of need for achievement (63.0%), a moderate need for independence (70.0%), and a moderate inclination towards risk-taking behavior (54.0%). In contrast, postgraduate students displayed a high level of need for achievement (51.0%), a substantial need for independence (50.0%), a notable propensity for risk-taking behavior (68.0%), and also exhibited a medium level of entrepreneurial motivation (53.0%).

Self-Cultivation According to Li Zhi and Its Paradoxes

This essay delves into the significance of self-cultivation in the thought of Li Zhi (1527–1602), particularly the process of rediscovering one’s childlike innocence (tongxin 童心). This journey challenges conventional morals and doctrines due to Li Zhi’s various levels of interpretation, which scrutinize the concept of self and the objectives of self-cultivation. Li Zhi’s notion of the self develops some concepts elaborated within the School of Mind, notably those of Wang Ji (1498–1583), and reconstructs an alternative Chinese model of a self, centered on individual autonomy. His ideas provoke ethical and philosophical considerations from both intra-cultural and transcultural perspectives. Central to Li Zhi’s concept of self-cultivation is based on his psychological realism, which begins with an acknowledgment of the inherent “selfishness” of human nature. However, unlike Xunzi’s viewpoint, Li Zhi contends that this innate selfishness is not the cause of conflicts and disorder. On the contrary, it is the source of morality and a positive dynamic force both in society and in personal life. He harnesses the concept of emptiness inherited from Buddhism and Wang Ji, employing it as a practical and secular tool to liberate individuals from biases, authoritarian dictates, and social norms. Situated within the framework of the cult of qing and the reclamation of emotions and desires, Li Zhi’s notion of the childmind, with its natural inclinations, self-interests, and desires, resonates with modern psychological theories on the flow of consciousness and self-motivation, as well as contemporary discussions on the morality of self-interest. This juxtaposition unveils the paradox of “Unsocial sociability,” prompting an exploration of the intricate relationship between sociability and selfishness. Questions remain, then, concerning the efficacy of self-cultivation in fostering the spontaneous expression of moderate and genuine inclinations. Can such self-cultivation establish a moral standard accessible to all, on their own terms, while simultaneously preventing harm among individuals (bu xianghai 不相害)? These inquiries underscore the complexity inherent in Li Zhi’s philosophy and invite further contemplation on the dynamics of selfhood and ethical conduct.

Research on the Dissemination Strategies of Traditional Culture in Anime Illustrations and Picture Books - Based on the Application of Information Diffusion Models

Abstract Animation illustrations and picture books themed on traditional culture play a crucial role in its dissemination. This paper analyzes the present scenario of traditional cultural transmission via these mediums and introduces an information diffusion model as the theoretical framework for subsequent questionnaire design and analysis. The model incorporates the theory of network dimensional force and information diffusion resistance to depict the diffusion process within cyberspace, accounting for the constraints imposed by information resistance. This results in a model that accurately mirrors the realities of the network environment. The study further examines the velocity and distortion in information diffusion, exploring the model’s diffusion scale and laws. In assessing the diffusion effectiveness through a questionnaire on cartoon illustrations and picture books, findings indicate a moderate inclination towards purchases, with average willingness and mean purchase values at 3.32 and 3.35, respectively. The analysis reveals that the pivotal factors affecting dissemination include content knowledge, thematic significance, and channel preferences, all scoring an average of 4 in terms of mean and median values. However, the overall satisfaction with the dissemination of traditional culture remains moderate among respondents. To enhance the dissemination effectiveness, it is imperative to advance the construction of conventional cartoon-quality illustrations and picture books, thereby fostering a more robust propagation of traditional culture.

Asymmetric capture into Neptunian 1:2 resonance

The asymmetric resonance configuration characterised by the critical angle librating around centres other than 0° or 180° is found in the 1:N mean motion resonance. The asymmetric 1:2 resonance with Neptune is of particular interest because the two asymmetric islands seem to host different populations, and this might be a direct clue to understanding the early evolution of the Solar System. The asymmetry has been investigated from both observational and theoretical perspectives, but conclusions among studies vary widely. In this paper, using toy models, we carefully designed a series of tests to systematically study the capture of planetesimals into the leading and trailing resonance islands. Although these tests may not exactly reproduce the real processes the Solar System experienced, they reveal some typical dynamics in the resonance capture. Since the real Twotinos have small to moderate inclinations, as a first attempt, we adopted planar models in this paper in order to investigate the mechanisms that may lead to asymmetric capture by the leading and trailing islands, including their size variation during the outward migration of Neptune, the stickiness of the leading island, and the migration slowdown effect. We find that the ratio between the populations of the leading and trailing islands can be easily tuned by introducing the slowdown effect into the migration model, and thus it may not be a good tracer of the migration history. However, the eccentricity of objects trapped in two asymmetric islands may conserve some valuable information of the early evolution of the Solar System.

Exposure to inclined trunk postures in surgical staff

In surgical staff, low-back pain (LBP) is prevalent and prolonged trunk inclination is hypothesized to be one of its potential causes. The aim of this study was to evaluate the magnitude and duration of trunk inclination in the sagittal plane of surgical assistants during surgical procedures. The three-dimensional trunk orientation was measured in 91 surgical assistants across four medical facilities during surgical procedures using an inertial measurement unit on the thorax. Per participant, Exposure Variation Analysis was used to evaluate the percentage of the total time of trunk inclination (< -10° (backward inclination); -10–10° (upright posture); 10–20° (light inclination); 20–30° (moderate inclination); >30° (strong inclination)) taking into account posture duration (< 10 s; 10–60 s; 60–300 s; > 300 s). Participants reported their LBP history and perceived low-back load during the procedure via a questionnaire. Participants were in an upright posture for 75% [63–84%] (median [interquartile range]) of the total surgery time (average surgery time: 174 min). Trunk inclination was beyond 20° and 30° for 4.3% [2.1–8.7%] and 1.5% [0.5–3.2%] of the surgery time, respectively. In most of the participants, the duration of trunk inclination beyond 20° or 30° was less than 60 s. Questionnaire response rate was 81%. Persistent or repeated LBP was reported by 49% of respondents, and was unrelated to the exposure to inclined trunk postures. It is concluded that other factors than prolonged trunk inclination, for instance handling of loads or prolonged standing may be causally related to the reported LBP in the investigated population.

Polarimetry and astrometry of NIR flares as event horizon scale, dynamical probes for the mass of Sgr A*

We present new astrometric and polarimetric observations of flares from Sgr A* obtained with GRAVITY, the near-infrared interferometer at ESO’s Very Large Telescope Interferometer (VLTI), bringing the total sample of well-covered astrometric flares to four and polarimetric flares to six. Of all flares, two are well covered in both domains. All astrometric flares show clockwise motion in the plane of the sky with a period of around an hour, and the polarization vector rotates by one full loop in the same time. Given the apparent similarities of the flares, we present a common fit, taking into account the absence of strong Doppler boosting peaks in the light curves and the EHT-measured geometry. Our results are consistent with and significantly strengthen our model from 2018. First, we find that the combination of polarization period and measured flare radius of around nine gravitational radii (9Rg ≈ 1.5RISCO, innermost stable circular orbit) is consistent with Keplerian orbital motion of hot spots in the innermost accretion zone. The mass inside the flares’ radius is consistent with the 4.297 × 106 M⊙ measured from stellar orbits at several thousand Rg. This finding and the diameter of the millimeter shadow of Sgr A* thus support a single black hole model. Second, the magnetic field configuration is predominantly poloidal (vertical), and the flares’ orbital plane has a moderate inclination with respect to the plane of the sky, as shown by the non-detection of Doppler-boosting and the fact that we observe one polarization loop per astrometric loop. Finally, both the position angle on the sky and the required magnetic field strength suggest that the accretion flow is fueled and controlled by the winds of the massive young stars of the clockwise stellar disk 1–5″ from Sgr A*, in agreement with recent simulations.

Design, synthesis, metal chelation potential and biological evaluation of pyridine chalcones as multi-target-directed ligands against Alzheimer's disease

Two sets of 1-phenyl-3-(pyridinyl) prop‑2-en-1-one analogs, 7a-d and 8a-d were designed by the incorporation of pyridine and chalcone privileged scaffolds with the objective of developing multifunctional molecules for Alzheimer's disease (AD). The structure-based approach was used to evaluate the binding potential of the designed pyridine chalcone series in acetylcholinesterase, prior to synthesis. The hybrid molecules designed from the amalgamation of two privileged scaffolds demonstrated excellent potential for simultaneous inhibition of acetylcholinesterase (AChE) and amyloid beta (Aβ1–42) aggregation in addition to promising radical scavenging activities, metal-chelating properties and inhibitory potential for attenuation of advanced glycation products. The compounds showed mixed inhibition of AChE in enzyme kinetic studies with the most potent compound 8c showing an IC50 value of 0.1 ± 0.01 μM. Compounds of both series exhibited good potential of inhibiting Aβ1–42 aggregation, with compound 8c exhibiting an inhibitory potential of 83.58% after 48 h. The molecules demonstrated moderate to good radical scavenging activity in both DPPH and H2O2 radical scavenging assays, moderate inclination for metal chelation and significant potential to inhibit formation of advanced glycation products. The mechanistic basis of these actions has been probed by experimental and computational techniques that leads to greater understanding of the underlying structural basis for the activities of these promising molecules for holistic treatment of AD. Taken together, this work reveals the multifaceted pleiotropy of the designed molecules, especially the 4-pyridine analogs, with the compounds 8b and 8c demonstrating excellent potential as multi-target directed ligands to address most of the causative pathologies of AD.

Weeding out the Truth: A Survey Experiment on the Role of Scientific Evidence in Shaping Public Opinion on Marijuana Policy

PurposeThis study aims to explore the extent to which different forms of scientific research on the criminogenic effects of marijuana use impact public opinion on marijuana-related policy issues. MethodsWe conducted an experimental priming survey using Qualtrics, targeting heads of households in South Carolina with associated email addresses. Multiple OLS regression models were employed to analyze single-item and aggregate scores of our dependent variables. ResultsOur findings reveal that, except for the policy regarding the immediate release of a convicted offender, scientific research on the criminogenic effects of marijuana use did not significantly or substantively influence public perceptions of cannabis policies. Factors such as perceptions of police legitimacy, legal orientation, trust in law enforcement, and conservative or moderate political inclinations were significantly correlated with various outcomes. ConclusionsRespondents primed with research suggesting a link between marijuana use and an increased likelihood of engaging in violent and property crimes were more inclined to disapprove of releasing non-violent cannabis offenders from incarceration. However, exposure to scientific research generally did not influence participants' support or disapproval of other policies promoting the liberalization of marijuana-related policies. The study also discusses potential research and policy implications.

Inclined colloidal drops: Evaporation kinetics and pattern formation

The drying of solute-laden drops is ubiquitous in everyday life, from paints and printers to the raindrops drying on our windows. Nonetheless, scientific interest has primarily focused on understanding the evaporation kinetics on flat surface, with the key parameter of substrate inclination only recently started being addressed. This work focuses on the influence of moderate substrate inclinations at 20° and 40° on the evaporation kinetics and associated deposit patterns of colloidal drops. Inclination altered the shape of the drops which formed a lower contact angle at the upper side of the drop (rear edge) and larger contact angle at the lower side (front edge). As evaporation rate is a function of contact angle, which in turn is a function of inclination, the evaporation lifetime was extended by 43% and 61% for 20° and 40°, respectively, compared to a flat drop. A theoretical approximation of the evaporative flux across the liquid-vapour interface of the drops showed the contribution of each edge to the evaporation kinetics. These differences in the evaporative fluxes altered the internal flows within the drop and in turn the coffee-ring formation mechanism. The particle deposit shape at the two edges for each drop was visualised which combined with the theoretical arguments allowed the proposition of the particle deposition mechanism in inclined drops: inclination added a gravitationally-driven velocity flow component within the drops, which is perpendicular and hence negligible in flat drops. This additional flow hindered or enhanced the number of particles arriving at the rear and front edges of the inclined drops, respectively, and hence influenced the dimensions of the coffee-ring patterns. Eventually, the particle deposits grew sufficiently tall to effectively stagnate the outward flow which resulted in enhanced particle accumulation at the interior of the drops as inclination increased.

Analytical Study of the Co-orbital Motion in the Circular Restricted Three-body Problem

In the restricted three-body problem (RTBP), if a small body and a planet stably orbit around a central star with almost exactly the same semimajor axis, and thus almost the same mean motion, this phenomenon is called the co-orbital motion, or equivalently, the 1:1 mean motion resonance. The classical expansion of the disturbing function is divergent when the semimajor axis ratio of the small body to the planet is close to unity. Thus, most of the previous studies on the co-orbital dynamics were carried out through numerical integrations or semi-analytical approaches. In this work, we construct an analytical averaged model for the co-orbital motion in the framework of the circular RTBP. This model is valid in the entire coorbital region except in the vicinity of the collision singularity. The results of the analytical averaged model are in good agreement with the numerical averaged model even for moderate eccentricities and inclinations. The analytical model can reproduce the tadpole, horseshoe and quasi-satellite orbits common in the planar problem. Furthermore, the asymmetry of 1:1 resonance and the compound orbits (Icarus 137:293–314) in the general spatial problem can also be obtained from the analytical model.

Lifelong learning and personal learning environments: a productive symbiosis in higher education

The aim of this study was to analyze lifelong learning (LLL) and its relationship with the educational approach of the personal learning environment (PLE). In the last year students do various degrees at a university in Costa Rica. METHOD. Using a non-experimental, transactional design, we applied a probabilistic questionnaire where the representative sample was (n=1187). RESULTS. The results show that the LLL scale used is a valid, and the tool used to explore the topic is reliable. In addition, we saw a moderate inclination towards lifelong learning in the students, mainly about all the application capability of new knowings and skills in practical surroundings, and how they relate to the new learning with previous acquisitions. DISCUSSION. It is observed a significant relationship among this training approach and personal learning environments, characterized by the use of the potential offered by technological tools. It has been found significant differences by gender, knowledge area, academic performance, and internet connection hours. Among the conclusions, it is pointed out that the universities must foster the linked competences with LLL to boost the PLE of the learners and propitiate its optimum social and professional insertion along their vital route.

Mechanical properties and failure law of composite rock containing two coplanar fractures

Composite rocks comprise the rock structures that are commonly used in geotechnical engineering. The fracture configuration has a substantial influence on the mechanical behavior, failure mode, and crack propagation of composite rocks. In this study, we considered a composite rock with two prefabricated coplanar fractures. Through laboratory uniaxial compression tests and using a digital image acquisition system, we systematically studied the effects of different fracture lengths and inclination angles on the mechanical properties and failure characteristics of the rocks. We obtained the following results: 1) during the loading deformation of the rock sample, the peak stress and elastic modulus increased with an increase in the fracture inclination angle and decreased with an increase in the fracture length. The deterioration coefficient k (the ratio of the difference between the peak strength of intact and fractured rock sample to that of intact rock sample) decreased with an increase in the fracture inclination angle and increased with an increase in the fracture length. 2) The failure type of the rock samples was primarily controlled by the fracture inclination angle and material of the two rock types, and the fragmentation degree was primarily controlled by the fracture length. With an increase in the fracture inclination angle, the failure mode of rock sample exhibited the following order of changes leading to failure: a double-Y type (trwo wing and one antiwing cracks appeared on each prefabricated fracture) → double-Z type (two wing cracks appeared on each prefabricated fracture) → Z type (one wing crack appeared on each prefabricated fracture). 3) The type of coalescence of the rock bridge was controlled by the fracture inclination angle and structural plane. The crack positions were primarily affected by the fracture length. 4) At a low fracture inclination angle (α ≤ 30°), the propagation of the microcracks showed aggregated band formation. Above moderate fracture inclination angles (α &amp;gt; 30°), the microcrack aggregation band gradually weakened and expanded in the direction of dispersion.

Influence of a residential drug and alcohol program on young people's criminal conviction trajectories

BackgroundThis study examined the effect of a residential drug and alcohol therapeutic community program on criminal convictions among young people who had different trajectories of conviction prior to referral. MethodData was derived from linked administrative records of all young people referred to a modified therapeutic community for serious alcohol and drug related difficulties located in New South Wales, Australia (n = 3059). Group-based trajectory modelling and propensity score matching estimated the potential treatment effect at age 17 on subsequent convictions up to 22 years of age, by three pre-referral trajectories of convictions from ages 10 to 16 years, designated “no or low convictions”, “moderate incline convictions”, and “high incline convictions”. ResultsTreatment was associated with a significant decrease in convictions for only the high incline convictions trajectory after double adjustment of propensity scores and post-discharge incarceration. The reduction in the number of convictions for the high incline group was substantial (Cohen's d = 0.96), corresponding to 4.36 fewer convictions over five years post referral. ConclusionsResidential therapeutic communities may be an effective intervention to reduce future convictions among young people with drug and alcohol problems who have a high number of convictions prior to referral.