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Accurate airborne aerosol instrumentation is required to determine the spatial distribution of ambient aerosol particles, particularly when dealing with the complex vertical profiles and horizontal variations of atmospheric aerosols. A versatile water-based condensation particle counter (vWCPC) has been developed to provide aerosol concentration measurements under various environments with the advantage of reducing the health and safety concerns associated with using butanol or other chemicals as the working fluid. However, the airborne deployment of vWCPCs is relatively limited due to the lack of characterization of vWCPC performance at reduced pressures. Given the complex combinations of operating parameters in vWCPCs, modeling studies have advantages in mapping vWCPC performance. In this work, we thoroughly investigated the performance of a laminar-flow vWCPC using COMSOL Multiphysics® simulation coupled with MATLAB™. We compared it against a modified vWCPC (vWCPC model 3789, TSI, Shoreview, MN, USA). Our simulation determined the performance of particle activation and droplet growth in the vWCPC growth tube, including the supersaturation, Dp,kel,0 (smallest size of particle that can be activated), Dp,kel,50 (particle size activated with 50 % efficiency) profile, and final growth particle size Dd under wide operating temperatures, inlet pressures P (30–101 kPa), and growth tube geometry (diameter D and initiator length Lini). The effect of inlet pressure and conditioner temperature on vWCPC 3789 performance was also examined and compared with laboratory experiments. The COMSOL simulation result showed that increasing the temperature difference (ΔT) between conditioner temperature Tcon and initiator Tini will reduce Dp,kel,0 and the cut-off size Dp,kel,50 of the vWCPC. In addition, lowering the temperature midpoint (Tmid=Tcon+Tini2) increases the supersaturation and slightly decreases the Dp,kel. The droplet size at the end of the growth tube is not significantly dependent on raising or lowering the temperature midpoint but significantly decreases at reduced inlet pressure, which indirectly alters the vWCPC empirical cut-off size. Our study shows that the current simulated growth tube geometry (D=6.3 mm and Lini=30 mm) is an optimized choice for current vWCPC flow and temperature settings. The current simulation can more realistically represent the Dp,kel for 7 nm vWCPC and also achieved good agreement with the 2 nm setting. Using the new simulation approach, we provide an optimized operation setting for the 7 nm setting. This study will guide further vWCPC performance optimization for applications requiring precise particle detection and atmospheric aerosol monitoring.

As one of the most characteristic components of ancient Chinese architecture, Dougong has an important significance in the history of ancient Chinese architecture, but with the passage of time, wooden building components are prone to decay and missing, so it is particularly important to digitally retain the Dougong. In order to realize the Dougong component segmentation, this paper proposes a super voxel-based Dougong component primitive segmentation method, which is divided into two parts: firstly, super voxelizing the Dougong point cloud data, and secondly, realizing the Dougong component primitive segmentation by using multi-geometric constrained region growth algorithm. In order to verify the effectiveness of the method, this paper selects three main Dougong types of the Qing Dynasty, including pingshenke, jiaoke, zhutouke, for experimental validation, and the results show that the combination of super voxel and regional growth algorithm can effectively extract the geometric primitive surface of the Dougong components with high extraction efficiency and good adaptability, which can be prepared for the subsequent knowledge of Dougong construction method to achieve component segmentation.

We report on a successful application of the horizontal-to-vertical spectral ratio (H / V) method, generally used to investigate the subsurface velocity structures of the shallow crust, to estimate the Antarctic ice sheet thickness for the first time. Using three-component, five-day long, seismic ambient noise records gathered from more than 60 temporary seismic stations located on the Antarctic ice sheet, the ice thickness measured at each station has comparable accuracy to the Bedmap2 database. Preliminary analysis revealed that 60 out of 65 seismic stations on the ice sheet obtained clear peak frequencies (f0) related to the ice sheet thickness in the H / V spectrum. Thus, assuming that the isotropic ice layer lies atop a high velocity half-space bedrock, the ice sheet thickness can be calculated by a simple approximation formula. About half of the calculated ice sheet thicknesses were consistent with the Bedmap2 ice thickness values. To further improve the reliability of ice thickness measurements, two-type models were built to fit the observed H / V spectrum through non-linear inversion. The two-type models represent the isotropic structures of single- and two-layer ice sheets, and the latter depicts the non-uniform, layered characteristics of the ice sheet widely distributed in Antarctica. The inversion results suggest that the ice thicknesses derived from the two-layer ice models were in good concurrence with the Bedmap2 ice thickness database, and that ice thickness differences between the two were within 300 m at almost all stations. Our results support previous finding that the Antarctic ice sheet is stratified. Extensive data processing indicates that the time length of seismic ambient noise records can be shortened to two hours for reliable ice sheet thickness estimation using the H / V method. This study extends the application fields of the H / V method and provides an effective and independent way to measure ice sheet thickness in Antarctica.

In this paper, Statistical Distribution based Conditional Random Fields (STA-CRF) algorithm is exploited for improving marginal ice-water classification. Pixel level ice concentration is presented as the comparison of methods based on CRF. Furthermore, in order to explore the effective statistical distribution model to be integrated into STA-CRF, five statistical distribution models are investigated. The STA-CRF methods are tested on 2 scenes around Prydz Bay and Adélie Depression, where contain a variety of ice types during melt season. Experimental results indicate that the proposed method can resolve sea ice edge well in Marginal Ice Zone (MIZ) and show a robust distinction of ice and water.

Satellite altimetry plays an important role in many geoscientific and environmental studies of Antarctic ice sheet. The ranging accuracy is degenerated near coasts or over nonocean surfaces, due to waveform contamination. A postprocess technique, known as waveform retracking, can be used to retrack the corrupt waveform and in turn improve the ranging accuracy. In 2010, the CryoSat-2 satellite was launched with the Synthetic aperture Interferometric Radar ALtimeter (SIRAL) onboard. Satellite altimetry waveform retracking methods are discussed in the paper. Six retracking methods including the OCOG method, the threshold method with 10 %, 25 % and 50 % threshold level, the linear and exponential 5-β parametric methods are used to retrack CryoSat-2 waveform over the transect from Zhongshan Station to Dome A. The results show that the threshold retracker performs best with the consideration of waveform retracking success rate and RMS of retracking distance corrections. The linear 5-β parametric retracker gives best waveform retracking precision, but cannot make full use of the waveform data.

Leaves falling gently or fluttering are common phenomenon in nature scenes. The authenticity of leaves falling plays an important part in the dynamic modeling of natural scenes. The leaves falling model has a widely applications in the field of animation and virtual reality. We propose a novel modeling method of fluttering leaves based on point cloud in this paper. According to the shape, the weight of leaves and the wind speed, three basic trajectories of leaves falling are defined, which are the rotation falling, the roll falling and the screw roll falling. At the same time, a parallel algorithm based on OpenMP is implemented to satisfy the needs of real-time in practical applications. Experimental results demonstrate that the proposed method is amenable to the incorporation of a variety of desirable effects.

The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 107 to 1010 cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 109 cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

This study presents the results from two sets of 18-year air quality simulations over the Northeastern US performed with a regional photochemical modeling system. These two simulations utilize different sets of lateral boundary conditions, one corresponding to a time-invariant climatological vertical profile and the other derived from monthly mean concentrations extracted from archived ECHAM5-MOZART global simulations. The objective is to provide illustrative examples of how model performance in several key aspects – trends, intra- and interannual variability of ground-level ozone, and ozone/precursor relationships – can be evaluated against available observations, and to identify key inputs and processes that need to be considered when performing and improving such long-term simulations. To this end, several methods for comparing observed and simulated trends and variability of ground level ozone concentrations, ozone precursors and ozone/precursor relationships are introduced. The application of these methods to the simulation using time-invariant boundary conditions reveals that the observed downward trend in the upper percentiles of summertime ozone concentrations is captured by the model in both directionality and magnitude. However, for lower percentiles there is a marked disagreement between observed and simulated trends. In terms of variability, the simulations using the time-invariant boundary conditions underestimate observed inter-annual variability by 30%–50% depending on the percentiles of the distribution. The use of boundary conditions from the ECHAM5-MOZART simulations improves the representation of interannual variability but has an adverse impact on the simulated ozone trends. Moreover, biases in the global simulations have the potential to significantly affect ozone simulations throughout the modeling domain, both at the surface and aloft. The comparison of both simulations highlights the significant impact lateral boundary conditions can have on a regional air quality model's ability to simulate long-term ozone variability and trends, especially for the lower percentiles of the ozone distribution.

Introduction Conjugal homicide refers to the act of killing a current or former intimate life partner, regardless of their marital status. This type of behavior is still inadequately addressed by prevention programs, as it is often regarded as exceptional compared to other forms of domestic violence. Objectives To describe the sociodemographic, clinical, and criminological data of individuals who commit spousal homicide. Methods This is a retrospective descriptive study of 21 psychiatric expertise files conducted between January 2002 and September 2023 in the psychiatric department of Hedi Chaker Hospital in Sfax. Sociodemographic, clinical, and criminological data were collected from criminal psychiatric expertise files and supplemented with information from medical records. Results The perpetrators of spousal homicide were predominantly male (85.7%), had an educational level above secondary school (57.1%), were married (85.7%), and had an average age at the time of the act of 40.3 years. Most of them had no psychiatric history (81%) or legal history(85%), and only 19% were using psychoactive substances. Among the perpetrators, 66.7% had a history of violence against their partners, with threats of homicide in 19% of cases. The majority of homicides occurred during the day (42.9%), in a public place (28.6%), were perpetrated in isolation (95.2%), happened impulsively (47.6%), and employed a single method (81%), with knives being the primary weapon (42.9%). In 76.2% of cases, the perpetrators of spousal homicides were found criminally responsible, while 19% were hospitalized in a psychiatric setting as part of a judicial non-prosecution decision. Conclusions The study of specific characteristics of spousal homicides holds crucial importance for the early detection of domestic violence situations that carry a lethal risk. By highlighting these particularities, it enables the development of more targeted prevention strategies. Disclosure of Interest None Declared

Introduction The evaluation of manic behavior with later onset is crucial, as various organic factors such as medications, infections, metabolic disturbances, tumors, and epilepsy can serve as potential etiological causes. While not universally observed, most studies indicate a connection between late-onset mania and neurological disorders like neurosyphilis. Objectives Our study aims to investigate the relationship between late-onset mania and neurosyphilis. Methods In this paper, we present a case of neurosyphilis presenting exclusively with symptoms of mania. Results A 72-year-old Tunisian woman with no prior medical or psychiatric history was referred to the psychiatric emergency room due to alterations in her mental state and behavior over the past ten days. During the psychiatric assessment, she displayed increased motor activity, fluctuating emotions, and rapid flow of ideas. The general physical examination yielded no notable findings. The serum Venereal Disease Research Laboratory (VDRL) test returned a strongly positive result (+++), and the TPHA examination confirmed a positive result at a titer of 1/60. In the serologic analysis of cerebrospinal fluid, VDRL was also positive, thereby confirming the diagnosis of neurosyphilis (NS). The diagnosis of mania secondary to a medical condition was established. The patient was treated with ceftriaxone and antimanic medications, resulting in a significant improvement in her psychiatric symptoms within a few days. Conclusions This case underscores the importance of conducting serologic testing for syphilis in patients who present with manic symptoms, experience a late-onset mental disorder, and have no prior history or family history of affective disorders. Disclosure of Interest None Declared

Introduction Emigration has a substantial impact on Tunisia’s healthcare sector. Graduates, including medical students at different educational levels, as well as general practitioners and specialists, often choose to emigrate. Some do so to pursue further studies abroad, while others seek careers and settlement primarily in Europe. This phenomenon exerts a significant influence on the quality of healthcare systems in their home countries. Objectives To evaluate the inclination to emigrate among medical residents employed in Tunisian healthcare institutions and to identify the factors associated with this intention. Methods This is a descriptive cross-sectional study conducted among medical residents undergoing their training in various healthcare facilities in Tunisia. The study employed an online questionnaire to assess the degree of satisfaction with various aspects of their professional life and the socio-economic situation in the country, as well as their intention to emigrate. Satisfaction levels were measured using a 4-point Likert scale, ranging from “very dissatisfied” to “very satisfied”. Results A total of 50 physicians participated in the survey. Among them, 72% were female, 80% were single, with an average age of 27.72 years at the time of the study. Regarding their professional status, 84% worked in university hospitals, 16% specialized in surgery, 40% specialized in medicine, and 44% were family physicians. The majority were students from the Faculty of Medicine in Sfax (56%), with 30% in Monastir, 8% in Tunis, and 6% in Sousse. The study found that 68% of medical residents expressed an intention to emigrate. Among the participants, 74% were dissatisfied with their working conditions, and 68% were dissatisfied with workplace safety. Additionally, 84% were dissatisfied with their salaries, 40% with their workload, 54% with supervision, and the quality of training provided in their hospitals. The political situation in the country and social security were considered unsatisfactory by 92% and 90% of the participants, respectively. Among the potential reasons studied to explain this emigration phenomenon, working conditions were a factor in 54% of cases, salary in 56%, training in 36%, and quality of life in 56%. Conclusions The emigration of young Tunisian medical professionals is driven by a range of factors, including working conditions, salaries, training opportunities, and quality of life. To counteract this phenomenon, it is crucial to enhance these aspects in order to retain these talented individuals in the country and thereby bolster the Tunisian healthcare system. Disclosure of Interest None Declared

Introduction The burnout syndrome is a blend of physical exhaustion and emotional fatigue that impairs an individual’s performance at work. In Tunisia, factors like working hours, the frequency of monthly shifts, and the physical and emotional abuse that physicians face from patients have collectively led to a significant incidence of burnout among medical professionals. Objectives To evaluate the prevalence of burnout syndrome among medical residents working in healthcare facilities in Tunisia and to pinpoint the contributing factors. Methods This study is a descriptive cross-sectional survey conducted among medical residents completing their training in various healthcare facilities in Tunisia. The study employed an online self-administered questionnaire and assessed burnout across three dimensions: personal burnout, professional burnout, and relational burnout, using the Copenhagen Burnout Inventory (CBI). Results A total of 50 physicians took part in the survey. Among them, 72% were female, 80% were single, and the average age at the time of the study was 27.72 years. Concerning their professional status, 84% worked in university hospitals, 16% specialized in surgery, 40% specialized in medicine, and 44% were family physicians. The majority were students from the Faculty of Medicine in Sfax (56%), with 30% in Monastir, 8% in Tunis, and 6% in Sousse. Regarding their work hours, more than 40 hours per week were reported by 32% of participants. According to the CBI scale, 12% of participants had scores indicating severe personal burnout, while 20% had scores indicating moderate personal burnout. Additionally,16% reported severe professional burnout, and 12% had scores suggesting severe relational burnout. In contrast, only 8% had scores indicating moderate relational burnout. The sociodemographic and professional factors that were studied, such as weekly working hours, monthly shifts, specialty, and workplace, did not show a significant correlation with the presence of burnout syndrome. Conclusions Burnout syndrome among medical resident physicians not only impacts their physical and mental well-being but also reduces their effectiveness and motivation at work. It is essential to introduce stress management strategies within hospitals to foster a healthier work-life balance. Disclosure of Interest None Declared

Introduction While postictal mania is a well-recognized clinical condition, it has received less research attention compared to other postictal manifestations. Objectives Drawing upon an analysis of a case report that underscores the clinical and therapeutic challenges associated with comorbid epilepsy and mania, a literature review was carried out to investigate the connection between these two disorders. Methods We illustrate a case of comorbidity between mania and epilepsy and provide a concise review of the literature summarizing the key characteristics of this association. Results This case pertains to Mr. M, a 44-year-old male with a history of frontal epilepsy characterized by secondary partial generalization, which was partially controlled with sodium valproate. He was admitted to our service due to acute agitation following a loss of consciousness lasting a few minutes. Upon admission, the patient exhibited symptoms of mental confusion. A neurological examination did not uncover any abnormalities. Brain computed tomography revealed mild frontal atrophy. Video electroencephalography conducted during the interictal period and outside the episodes of confusion did not reveal any abnormalities. The patient was restarted on sodium valproate (20 mg/kg/day) and clonazepam (2 mg/day). Following a lucid interval of ten days, the patient started to manifest psychiatric symptoms, which included irritability, hostility towards his spouse, increased talkativeness, thought pressure, and an unusual sense of familiarity, raising suspicion of post-ictal mania. Conclusions Based on this clinical case and the existing scientific literature, post-ictal mania occupies a distinct position among the mental disorders observed in the post-ictal period. Therefore, clinicians must be aware of these conditions to facilitate accurate diagnosis and appropriate management. Disclosure of Interest None Declared