Search Results (13)

This work aimed to assess the influence of the iQ Weight Control System on the weight, dimensional stability, and mechanical properties of injection-molded samples. The properties of products made from glass fiber-reinforced polyamide and 50% regrind from post-production waste were evaluated. The mechanical properties, such as impact strength and tensile strength, were measured to determine the material’s performance. Additionally, a spiral flow test was conducted to verify the process robustness and repeatability when producing with either virgin material or a blend of virgin and regrind material. The spiral flow test, which involves injecting the polymer melt into a spiral mold, provides insights into the processability and flow characteristics of the polymer under high shear rates. This test is crucial for assessing the consistency of the injection molding process and ensuring that the material maintains its properties across different production batches. Results demonstrated that, despite the viscosity reduction associated with regrind, the system successfully maintained a consistent shot weight, thereby stabilizing the amount of material injected into the mold cavity. The iQ Weight Control System activation led to an increase in impact strength from 9.50 kJ/m² to 10.78 kJ/m² for virgin samples and from 9.26 kJ/m² to 9.73 kJ/m for a 50/50 virgin/regrind blend. Full article

This paper discusses the use of IoT sensor networks and spatial data mining methods to support the design process in the revitalization of the university campus of the Warsaw University of Technology (WUT) in the spirit of universal design. The aim of the research was to develop a methodology for the use of IoT and edge computing for the acquisition of spatial knowledge based on spatial big data, as well as for the development of an open (geo)information society that shares the responsibility for the process of shaping the spaces of smart cities. The purpose of the article is to verify the hypothesis on whether it is possible to obtain spatial–temporal quantitative data that are useful in the process of designing the space of a university campus using low-cost Internet of Things sensors, i.e., already existing networks of CCTV cameras supported by simple installed beam-crossing sensors. The methodological approach proposed in the article combines two main areas—the use of IT technologies (IoT, big data, spatial data mining) and data-driven design based on analysis of urban space actors’ behavior for participatory revitalization of a university campus. The research method applied involves placing a network of locally communicating heterogeneous IoT sensors in the space of a campus. These sensors collect data on the behavior of urban space actors: people and vehicles. The data collected and the knowledge gained from its analysis are used to discuss the shape of the campus space. The testbed of the developed methodology was the central campus of the WUT (Warsaw University of Technology), which made it possible to analyze the time-varying use of the selected campus spaces and to identify the premises for the revitalization project in accordance with contemporary trends in the design of the space of HEIs (higher education institutions), as well as the needs of the academic community and the residents of the capital. The results are used not only to optimize the process of redesigning the WUT campus, but also to support the process of discussion and activation of the community in the development of deliberative democracy and participatory shaping of space in general. Full article

The indifference of Earth’s inhabitants towards progressive climate crises raises understandable anxiety for ecologists. Searching for effective forms of education aimed at radical and rapid change in attitudes is implemented in various areas of knowledge. This research combines linguistic, cognitive workshops and personality psychology, together with a selection of statistical tools. The results obtained through empirical research facilitated the construction of the semantic image of remorse and its wider (transcending the lexical) interpretation framework within self-aware emotional states and, specifically, moral feelings. The semantic analyses herein have become the grounds for educational guidelines within the process of attitude changes. Full article

The proteolytic and antioxidant systems are important components of humoral immunity, and these biomarkers indicate the immune status. These compounds are synthesized in the bees’ fat body and released into the hemolymph. Their functions maintain the organism’s homeostasis and protect it against adverse environmental factors (including pathogens). We determined the activities of acidic, neutral, and alkaline proteases and their inhibitors, as well as superoxide dismutase (SOD), catalase (CAT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and the level of total antioxidant potential (TAC). These compounds were investigated in the fat body and hemolymph in the females with increased reproductive potential, i.e., queens and rebels, and in normal (non-reproductive sterile non-rebel) workers. The phenoloxidase (PO) activities were determined in the hemolymph. The normal workers had higher activities of proteases and their inhibitors, SOD and CAT, in the fat body and hemolymph, compared to the queens and rebels. The protease inhibitors were not usually active in the queens. As we predicted, the rebels revealed values between those of the queens and normal workers. The highest activities of proteases and antioxidants were identified in the fat body from the third tergite in comparison with the sternite and the fifth tergite. These results are important for oxidative stress ecology and give a better understanding of the functioning of the fat body and the division of labor in social insects. Full article

Social insect societies are characterized by a high level of organization. This is made possible through a remarkably complex array of pheromonal signals produced by all members of the colony. The queen’s pheromones signal the presence of a fertile female and induce daughter workers to remain sterile. However, the lack of the queen mandibular pheromone leads to the emergence of rebels, i.e., workers with increased reproductive potential. We suggested that the rebels would have developed tergal glands and reduced Nasonov glands, much like the queen but contrary to normal workers. Our guess turned out to be correct and may suggest that the rebels are more queen-like than previously thought. The tergal gland cells found in the rebels were numerous but they did not adhere as closely to one another as they did in queens. In the rebels, the number of Nasonov gland cells was very limited (from 38 to 53) and there were fat body trophocytes between the glandular cells. The diameters of the Nasonov gland cell nuclei were smaller in the rebels than in the normal workers. These results are important for understanding the formation of the different castes of Apis mellifera females, as well as the division of labor in social insect societies. Full article

Rebel workers develop from eggs laid by the previous queen, before it went swarming and left the colony orphaned, until the emergence of a new queen. In contrast to normal workers developing in the queen’s presence, rebels are set to reproduce and avoid rearing of successive bee generations. They have more ovarioles in their ovaries, as well as more developed mandibular glands and underdeveloped hypopharyngeal glands, just like the queen. We posited that rebels are not only similar to queens in some anatomical features, but also develop in a shorter time in comparison to normal workers. Therefore, the aim of this study was to compare preimaginal development duration in rebel and normal workers. The results show that rebels, i.e., workers with a higher reproductive potential, had a significantly shorter preimaginal development period (mean ± SD, 19.24 ± 0.07 days) than normal workers (22.29 ± 0.32 days). Our result confirmed that workers who develop in a queen-less colony undergo a shorter preimaginal development than those in a queen-right colony. Full article

Life course theory (LCT) diagnoses childhood and adolescent factors that determine an individual’s involvement in crime in the future. Farrington lists eight key correlates identified by empirical analyses of criminal careers. In this paper, we seek to discuss the inconsistencies with LCT that we observed in our three empirical studies of the criminal careers of Polish offenders. During 12 years of qualitative research, we conducted direct observations and in-depth interviews in juvenile correction institutions (21) and prisons (8) across the country. We gained access to incarcerated (102) and released (30) juvenile offenders, as well as to incarcerated (68) and released (28) adult offenders. We also conducted in-depth interviews (92) with experts working with young and adult offenders. We similarly accessed some offenders’ criminal records and psychological opinions. Our study revealed the strong presence of family and neighborhood influences on early criminality. Contrary to LCT assumptions, state-dependent institutions (military, work, family) were not strong enough determinants of delinquency. Polish offenders generally experience criminal onset later than LCT-oriented criminologists indicate. Based on our data, we also agree with the thesis that the onset of crime should be discussed as different age-related periods rather than just a general onset. Full article

Intrauterine growth restricted (IUGR) pigs are characterized by high perinatal mortality and dysfunction of internal organs, adipose, and muscle tissues. However, little is known about the post-weaning performance and meat quality of the IUGR pigs. The aim of this study was to compare normal pigs and pigs with IUGR from birth until slaughter, also with respect to their meat quality. Pigs with the IUGR achieved lower slaughter weight but did not differ significantly from normal pigs in terms of their meat content. The IUGR did not negatively affect the culinary quality of the obtained meat, including its content of basic chemical components and energy value, as well as hardness, chewiness, cohesiveness, elasticity, and penetration force. The meat of the IUGR pigs, when compared to the meat of normal pigs, was characterized by higher pH, lower EC (Electrical Conductivity) and drip loss; it was also tenderer and obtained higher scores in sensory evaluation of taste, smell, and general desirability. Therefore, such raw material can be appreciated by the consumers and can be used for the production of culinary portions similarly to the raw material obtained from normal pigs. Full article

Investigating characteristics for the secondary breakup of dropping liquid is a fundamental scientific and practical problem in multiphase flow. For its solving, it is necessary to consider the features of both the main hydrodynamic and secondary processes during spray granulation and vibration separation of heterogeneous systems. A significant difficulty in modeling the secondary breakup process is that in most technological processes, the breakup of droplets and bubbles occurs through the simultaneous action of several dispersion mechanisms. In this case, the existing mathematical models based on criterion equations do not allow establishing the change over time of the process’s main characteristics. Therefore, the present article aims to solve an urgent scientific and practical problem of studying the nonstationary process of the secondary breakup of liquid droplets under the condition of the vibrational impact of oscillatory elements. Methods of mathematical modeling were used to achieve this goal. This modeling allows obtaining analytical expressions to describe the breakup characteristics. As a result of modeling, the droplet size’s critical value was evaluated depending on the oscillation frequency. Additionally, the analytical expression for the critical frequency was obtained. The proposed methodology was derived for a range of droplet diameters of 1.6–2.6 mm. The critical value of the diameter for unstable droplets was also determined, and the dependence for breakup time was established. Notably, for the critical diameter in a range of 1.90–2.05 mm, the breakup time was about 0.017 s. The reliability of the proposed methodology was confirmed experimentally by the dependencies between the Ohnesorge and Reynolds numbers for different prilling process modes. Full article

Recently, liquid biopsy has emerged as a tool to monitor oncologic disease progression and the effects of treatment. In this study we aimed to determine the clinical utility of liquid biopsy relative to conventional oncological post-treatment surveillance. Plasma cell-free (cf) DNA was collected from six healthy women and 37 patients with breast cancer (18 and 19 with stage III and IV tumors, respectively). CfDNA was assessed using the Oncomine Pan-Cancer Cell-Free Assay. In cfDNA samples from patients with BC, 1112 variants were identified, with only a few recurrent or hotspot mutations within specific regions of cancer genes. Of 65 potentially pathogenic variants detected in tumors, only 19 were also discovered in at least one blood sample. The allele frequencies of detected variants (VAFs) were <1% in cfDNA from all controls and patients with stage III BC, and 24/85 (28.2%) variants had VAFs > 1% in only 8 of 25 (32%) patients with stage IV BC. Copy number variations (CNVs) spanning CDK4, MET, FGFR1, FGFR2, ERBB2, MYC, and CCND3 were found in 1 of 12 (8%) and 8 of 25 (32%) patients with stage III and IV tumors, respectively. In healthy controls and patients without BC progression after treatment, VAFs were <1%, while in patients with metastatic disease and/or more advanced genomic alterations, VAFs > 1% and/or CNV were detected in approximately 30%. Therefore, most patients with stage IV BC could not be distinguished from those with stage III disease following therapy, based on liquid biopsy results. Full article

Film downflow from captured liquid without wave formation and its destruction is one of the most important aspects in the development of separation equipment. Consequently, it is necessary to create well-organized liquid draining in areas of captured liquid. Thus, the proposed 3D mathematical model of film downflow allows for the determination of the hydrodynamic parameters of the liquid film flow and the interfacial surface. As a result, it was discovered that the interfacial surface depends on the proposed dimensionless criterion, which includes internal friction stress, channel length, and fluid density. Additionally, equations for determining the averaged film thickness, the averaged velocity vectors over the film thickness, the longitudinal and vertical velocity components, and the initial angle of streamline deviation from the vertical axis were analytically obtained. Full article

Functionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material was used as an efficient mercury adsorbent, showing high adsorption efficiency. The adsorption isotherms were fitted using Freundlich and Langmuir models. The adsorption kinetics were fitted with pseudo-first order and pseudo-second order models. Adsorption selectivity was determined in the presence of cadmium ions and nickel ions. The presence of mentioned bivalent ions in the solution did not affect mercury adsorption efficiency. Full article

Introduction: Primary germ cell tumours with mediastinal location comprise 1–6% of mediastinal tumours and 2–5% of all germ cell tumours occurring in adults. They are identified mostly in the 3^rd decade of life, in 90% of cases in men. The most common symptoms are dyspnea, chest pain, cough, fever and weight loss. The aim of the present study was the analysis of our own results of treatment of primary germ cell tumours with mediastinal location, and a review of the literature concerning this subject. Material and Methods: Five patients (4 males, 1 female) median age 27.8 years (range 23–30 years) treated in the period from 1999 to 2009 in Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology, Department of Lung Cancer and Chest Tumours in Warsaw, due to germinal tumours with primary mediastinal location, entered the study. Results: All patients received chemotherapy according to the BEP regimen. All patients achieved an objective response to treatment. Two patients died due to disease progression in spite of II- and III-line treatment. Three patients are still in follow-up. The median survival time was 55.8 months (range 8.0–120.0 months). Conclusions: Primary mediastinal germ cell tumours have worse prognosis than do those with gonadal location. Based on our observations and review of the literature, it can be concluded that the results of treatment of non-seminoma type germ cell tumours with primary mediastinal location remain poor. Patients who develop early recurrence or progression during first-line chemotherapy are particularly at risk of unfavourable outcome. Identification of new standards of treatment in tumours resistant to cisplatin require further studies evaluating the effectiveness of new generation cytostatic drugs. Full article