4th Stage Research Articles

Role of magnetic resonance imaging in staging of rectal cancer and application AJCC 8th staging

Purpose: To evaluate the role of MRI in staging of rectal cancer according to AJCC 8th staging. Material and Methods: A cross sectional study with 31 histiologically proven rectal cancer patients treated at Hue Central Hospital from 01/2022 to 05/2023. Results: The accuracy of MRI in diagnosing stage T rectal cancer according to the AJCC 8th staging is 93.5% with Kappa coefficient = 0.866. The sensitivity, specificity, and accuracy of each stage were T1-T2: 75%, 100%, 75%; T3: 100%, 81,8%, 90,9%; T4: 100%, 100%, 100%. About 12.9% of patients invaded the mesorectal fascia (MRF +) on MRI. There was only 1 case of EMVI+. The sensitivity, specificity, and accuracy of MRI in dectecting lymph node metastasis was 80%, 66,7%,71%. Conclusion: MRI appears to be a highly accurate modality so when application AJCC 8th staging be can preoperative staging and decision-making treatment of rectal cancer Key words: magnetic resonance imaging, AJCC 8th staging, rectal cancer.

Molecular characterization of Aedes aegypti (L.), its bacterial microbiomes and their control in Saudi Arabia

Aim: This study aims to identify laboratory strains of Aedes aegypti at a molecular level and isolate bacteria from various developmental stages, while also assessing the effectiveness of environmentally friendly Bacillus subtilis compared to a commercial insecticide (Bacilod 5000 IU) containing Bacillus thuringiensis against the 4th larval stage of Ae. aegypti. Methodology: The molecular analysis revealed a new strain of Ae. aegypti and identified 24 bacterial strains from 9 distinct families. These novel strains were documented and deposited in the GenBank for future reference. Notably, in this study B. subtilis at different concentrations (1000, 3000, 5000, 7000 and 9000 ppm) was compared with Bacilod 5000 IU (0.1, 0.3, 0.5, 0.8 and 1 ppm). Results: The mortality rate of 4th instar larvae ranged from 12 to 93% for strains treated with the isolated bacteria B. subtilis and 14 to 92% for strains treated with the commercial insecticide B. thuringiensis IU. In comparison to B. subtilis, the commercial insecticide B. thuringiensis showed an approximate 8939.91 times higher relative resistance index. Interpretation: The results obtained in this study highlights the need for further research into isolated bacteria as potential biological controls for Ae. aegypti. Key words: Aedes aegypti, Bacillus subtilis, Biological control, Insecticides, Microbiomes

Neurexin drives Caenorhabditis elegans avoidance behavior independently of its post-synaptic binding partner neuroligin.

Neurexins and their canonical binding partners, neuroligins, are localized to neuronal pre-, and post-synapses, respectively, but less is known about their role in driving behaviors. Here, we use the nematode C. elegans to show that neurexin, but not neuroligin, is required for avoiding specific chemorepellents. We find that adults with knockouts of the entire neurexin locus exhibit a strong avoidance deficit in response to glycerol and a weaker defect in response to copper. Notably, the C. elegans neurexin (nrx-1) locus, like its mammalian homologs, encodes multiple isoforms, α and γ. Using isoform-specific mutations, we find that the γ isoform is selectively required for glycerol avoidance. Next, we used transgenic rescue experiments to show that this isoform functions at least partially in the nervous system. We also confirm that the transgenes are expressed in the neurons and observe protein accumulation in neurites. Furthermore, we tested whether these mutants affect the behavioral responses of juveniles. We find that juveniles (4th larval stages) of mutants knocking out the entire locus or the α-isoforms, but not γ-isoform, are defective in avoiding glycerol. These results suggest that the different neurexin isoforms affect chemosensory avoidance behavior in juveniles and adults, providing a general principle of how isoforms of this conserved gene affect behavior across species.

Mortality Effects of Beauveria bassiana and Purpureocillium lilacinum Isolates and Efficacy of a Wettable Formulation on Palemona prasina (Hemiptera: Pentatomidae) Nymphs

In this study, the mortality effect of two Beauveria bassiana and two Purpureocillium lilacinum isolates on the 4th stage nymphs of Palemona prassiana was determined. The most lethal isolate was formulated as wettable powder and tested on the pest. Furthermore, Y-tube olfactometry tests were conducted to detect behavioral response of the nymphs in presence of the fungus. All the experiments were carried out under controlled conditions. The mortality varied depending on the isolates between 28.51% and 82.14% on the 12th day. Beauveria bassiana FAI-38 caused the highest mortality (82.14% at 1x108 conidia ml-1) with LC50 and LT50 estimations of 3.3x106 conidia ml-1 and 8.4 days, respectively. According to data taken 6 and 12 days after application, the wettable powder formulation was found to be significantly more effective (89.65% at 1x107 conidia ml-1, LT50 6.08 days). According to the Y-tube olfactometry tests, the nymphs exhibited avoidance from unformulated B. bassiana spores; however, once the spores were formulated as wettable powder, the behavior of the insects changed to neutral. It is concluded that Beauveria bassiana FAI-38 presents a potential as a control agent, and the wettable powder formulation of the fungus improves its effectiveness by increasing mortality and removing repellency effect of the fungal spores.

An Overview of the Biological Aspects, Nature of Damage and Strategies for Managing the Gram Pod Borer (Helicoverpa armigera Hubner) in Chickpea: A review

Gram pod borer, Helicoverpa armigera, a globally widespread and cosmopolitan insect pest, poses a significant threat to chickpea productivity worldwide. The effective management of this pest is paramount for ensuring sustainable chickpea yields. The life cycle of H. armigera spans approximately 4-5 weeks, progressing through egg, larvae, pupae and adult stages. During the initial 1st to 3rd instar larval phases, the insect primarily engages in feeding on leaves, twigs, and flowers. As the larvae advance to the 4th to 6th instar stages, they shift their focus to developing pods, creating holes or bores and consuming entire seeds. Yield losses of up to 90 percent may occur, contingent upon insect density and cultivar susceptibility. A comprehensive approach to sustainable chickpea pod borer management encompasses the utilization of resistant cultivars, strategic manipulation of sowing dates, maintaining optimal crop density, nutritional management, deployment of trap crops (such as maize, sunflower, sorghum, safflower, pigeon pea, okra and tomato), installation of animated bird perches and the application of biological control measures involving plant extracts, virus/bacteria-based insecticides and entomopathogenic nematodes. In instances of pod borer outbreaks, chemical insecticides are considered a last resort for farmers. However, the adoption of resistant cultivars, adherence to recommended cultural practices and the integration of biological control methods have proven to be more efficacious, economically viable, sustainable and environmentally friendly in the management of chickpea pod borer.

Comparative assessment of hemodynamic parameters during anesthesia in orthopedic and traumatological operations on the lower extremities in children

Objective. To conduct a comparative analysis of hemodynamic parameters during orthopedic and traumatological operations on the lower extremities in children performed under conditions of multicomponent balanced general and combined anesthesia. Materials and methods. A single-center prospective study. The present study included 60 children aged 6 to 17 years who underwent planned orthopedic and trauma surgery interventions on the lower extremities. Patients were divided into two groups depending on the method of anesthesia: Group 1 (n = 25) - multicomponent balanced general anesthesia, Group 2 (n = 35) - combined anesthesia (multicomponent balanced general anesthesia in combination with regional blocks of the sciatic and femoral nerves). To solve these problems, a comparative analysis of heart rate, systolic, diastolic and mean arterial blood pressure was carried out at seven stages of the study: 1st stage - initial, child on the operating table; 2nd stage - induction of anesthesia; 3rd stage - placement of the laryngeal mask; 4th stage - start of the operation; 5th stage - traumatic stage of the operation; 6th stage - completion of the operation; 7th stage - after removal of the laryngeal mask. Results. In all cases, the surgical interventions were successful. The study found that in the group of children who underwent multicomponent general anesthesia at the 4th (start of surgery), 5th (traumatic stage of surgery) and 6th (end of surgery) stages, heart rate (HR) was higher compared to the group of combined anesthesia. Systolic and mean arterial blood pressure during the traumatic phase of surgery were also higher in children undergoing multicomponent general anesthesia. The values of diastolic blood pressure did not differ between groups throughout the study with the exception of the 3rd stage (laryngeal mask placement) where lower values were observed in patients of the Group 1. Diastolic blood pressure values did not differ between groups throughout the study, with the exception of 3th stage (laryngeal mask placement), where lower values were noted in Group 1 patients. Conclusion. Combined methods of anesthesia based on the combination of multicomponent general anesthesia and conductive peripheral nerve blocks provide the greatest hemodynamic stability during orthopedic and traumatologic surgeries on the lower extremities in children.

영산강유역 대형석실묘 출토 목관부속구의 변천과 의미

This paper presents the stages of the wooden coffin accessories of the large stone chamber tombs in the Yeongsan River Basin based on an examination and comparison of those wooden coffin accessories. In addition, through a comparison with examples from of the Baekje capital during the Ungjin period, the way in which the meaning of the wooden coffin accessories changed was observed. In the Ungjin period tombs of the Yeongsan River basin, wooden coffin accessories of different types were excavated, and it is believed that two to three coffins were generally used. The combination of wooden coffin accessories can be divided into four stages: the first stage is when headless nails were used; the second stage is when square-headed nails were used; the third stage is when circular coffin rings and round-headed nails were used; the fourth stage is when square coffin rings were added and round-headed nails continued to be used. It is estimated that the first stage is at the late of the 5th century, the second stage is early of the 6th century, the third and fourth stage is at the mid-6th century. The wooden coffin accessories excavated from Ungjin tombs in the Yeongsan River Basin differ in distribution pattern, and in the first half of the Ungjin period, such artifacts were identified in Dasi, Naju, and it is estimated that this area was related to Baekje from early on. In the late Ungjin period, the wooden coffins of the Baekje royal class tombs appear in the northern tombs of the Yeongsan River Basin and subsequently change in a similar manner. It is estimated that the groups that constructed the tombs in this region emerged through various roles, while maintaining a close relationship with the capital of Baekje. In addition, it is noteworthy that in the southwestern region of Naju in the early Sabi period, a pattern of wooden accessory combinations similar to that of the Baekje capital appeared. The use of wooden coffins was an important part of the burial ritual of ancient tombs, and it can be estimated, through the wooden coffin accessories, that almost the same burial rituals as that of the capital of Baekje were performed.

Prolongation of Safe Operation of the K-1000-60/3000 Turbine Power Unit after Damage to the HPC Rotor

Currently, when large-scale military actions are taking place on the territory of Ukraine, the inclusion of the domestic energy system in the European one is a reliable component of providing electricity to the country's energy market. However, according to experts, uninterrupted and safe operation of nuclear power plants is still considered a prerequisite for the stable operation of the energy sector of Ukraine. The purpose of the paper is to assess the damageability and individual resource of the rotor of high-pressure cylinder (HPC) of the K-1000-60/3000 turbine power unit of the LMZ after damage to the blades in order to prolong the operation of the power unit in the conditions of a stressed state of the power system. One of the most effective ways to partially solve the problem of replacement of generating capacities is to extend the operating periods of NPP power units after the end of the project operating period, provided that nuclear and radiation safety standards are met. The review of the previously established service life of the energy equipment of NPP power units involves the assessment of the residual resource of the energy equipment in accordance with the regulatory documents. After the accidental damage of the blades of the last stage of the HPC rotor of the K-1000-60/3000 turbine power unit of the LMZ, there was a need to study the cyclic and static damage, the individual residual resource of the HPC rotor. In the process of achieving the goal, studies were carried out for three design options: the original option (five stages of the HPC rotor), the option without the blades of the last stage and the option without the fifth stage (with four first stages). The calculation of the resource indicators of the rotor in the execution of the HPC without blades of the 5th stage shows that the static damage accumulated in the main metal is 52%, the cyclic damage is 5% when applying the standard strength reserves for the number of cycles and for deformations at the level of nN=10 and nε=1.5 according to the recommendations of SOU-N MEV 40.1-21677681-52:2011. Thus, the total damage to the base metal is 57%, which sets the residual resource of the HPC rotor at the level of 88.4 thousand hours. The calculation of the resource indicators of the rotor in the execution of the HPC without entire 5th stage shows that the static damage accumulated in the base metal is 52%, the cyclic damage is 6% when applying the standard strength reserves for the number of cycles and deformations at the above-mentioned level. The total damage to the base metal is 58%, which determines the residual resource of the HPC rotor at the level of 85.6 thousand hours.

Prognostic difference between surgery and external radiation in patients with stage I liver cancer based on competitive risk model and conditional survival rate.

This study aimed to assess the difference in prognosis of patients with early-stage liver cancer after surgery or external radiation. Between 2010 and 2015, 2155 patients with AJCC 7th stage I liver cancer were enrolled in the SEER database. Among these, 1972 patients had undergone surgery and 183 had undergone external beam radiation. The main research endpoints were overall survival (OS) and disease-specific survival (DSS). The competitive risk model was used to calculate the risk ratio of liver cancer-specific deaths when there was a competitive risk. Propensity Score Matching (PSM) method using a 1:1 ratio was used to match confounders such as sex, age, and treatment method. Conditional survival was dynamically assessed for patient survival after surgery or external radiation. Multivariate analysis of the competitive risk model showed that age, disease diagnosis time, grade, and treatment [surgery and external beam radiation therapy (EBRT)] were independent prognostic factors for patients with hepatocellular carcinoma. Surgery had a higher survival improvement rate than that of EBRT. As the survival of patients with liver cancer increased, the survival curve of surgery declined more slowly than that of radiotherapy patients and stabilized around 3 years after surgery. The survival curve of radiotherapy patients significantly dropped within 4 years and then stabilized. Surgery was better than EBRT for patients with stage I liver cancer. Close follow-up was required for 3 years after surgery or 4 years after external radiation. This study can help clinicians make better informed clinical decisions.

Optimization of irrigation period improves wheat yield by regulating source-sink relationship under water deficit

The optimization of irrigation scheduling presents an effective methodology for augmenting crop yields and enhancing water utilization efficiency. Nonetheless, a comprehensive understanding of the intricate mechanisms through which this strategy influences crop growth and yield formation is yet to be fully understood. In this study, a field experiment was conducted during the winter wheat cultivation period from 2018 to 2020 on two wheat cultivars: JM418, known for its drought tolerance, and SX828, known for its drought sensitivity. These treatments were subjected to four distinct irrigation schedules and two sowing stages. The timing of irrigation was specifically designed to coincide with the visibility of the 3rd, 4th, 5th, and 6th leaves for normal and postponed sowing. Our findings revealed that commencing irrigation at the stage when the 4th leaf becomes visible serves as an advantageous strategy for deficit irrigation. This approach significantly amplified winter wheat yield by 6.96–54.09 % and improved water use efficiency by 9.88–47.62 %. Quantitative analysis of source ability parameters demonstrated that postponed irrigation adversely affected the mean leaf area index (MLAI), total leaf area duration (TLAD), and biomass at maturity (BAM). Furthermore, an increase in mean net assimilation rate (MEAR) and harvest index (HI) was noted during the delayed irrigation phase when the 4th leaf was visible. The highest spike count per hectare was observed when irrigation was executed at the 4th leaf visibility stage, with an average increase of 13.98 %. Conversely, with a postponed irrigation schedule, the mean count of grain number per spike decreased by 2.47, while the 1000-grain weight saw an increase of 1.65 g. Higher sink capacity was obtained with irrigation when the 3rd and 4th leaves were visible. Despite this, the grain-leaf ratios when irrigated at the 4th, 5th, and 6th leaf visibility stages were significantly higher than those irrigated at the 3rd leaf visibility stage. In conclusion, our findings elucidate that the irrigation strategy coinciding with the 4th leaf visibility stage exhibits superior grain yield and water use efficiency (WUE) stability. This can be attributed to the enhanced harvest index, effective spike number per unit area, and biomass accumulation. Concurrently, the number of grains per panicle and the 1000-grain weight were relatively balanced. Our research offers novel insights into the mechanism of source-sink regulation in crops under deficit irrigation conditions and lays the groundwork for the development of precise and efficient irrigation strategies.

Utilizing the AJCC 8th Staging to Discriminate Survival Outcomes in HPV-associated Oropharyngeal Squamous Cell Carcinoma.

The American Joint Committee on Cancer (AJCC) staging 8th edition introduced major changes in the TNM staging of oropharyngeal squamous cell carcinoma (OPSCC) based on the human papillomavirus (HPV) status. This study aimed to observe how well the AJCC staging 8th edition precisely discriminates survival outcomes in patients with HPV-associated OPSCC using a large population database. Using the Surveillance, Epidemiology, and End Results database between 2010 and 2016, 7,448 patients with HPV-associated OPSCC were enrolled. Patients diagnosed with OPSCC and tested positive for HPV with information on the TNM staging according to the AJCC staging 7th edition were selected. Next, T-, N-, and clinical staging were reconstructed based on the AJCC staging 8th edition. Survival probabilities in both AJCC staging 7th and 8th editions were estimated and compared. Most patients (93.44%) were down-staged from the 7th to the 8th edition. The AJCC staging 8th edition showed more discriminatory power in predicting survival of patients with HPV-associated OPSCC than the AJCC staging 7th edition, regardless of the primary subsites. Additionally, clinical stage I patients with HPV-associated OPSCC according to the AJCC 8th edition showed better prognosis in case of high T staging than high N staging. Clinical staging according to the AJCC 8th edition compared to that of the 7th edition was an independent prognostic factor in patients with HPV-associated OPSCC. This study emphasizes the advantages of the new classification system for discriminating survival in HPV-associated OPSCC according to various factors.

ნინოწმინდის გაზნავთობიანი ბუდობის დამუშავება პროდუქტიულ ფენაზე ჰიდროდინამიკური ზემოქმედების მეთოდებით

Ninotsminda oil-and-gas bearing deposit connected with the fractured-cavernous reservoirs of the Middle Eocene volcanogenic-sedimentary suite is in its final, 4th stage of development (operates since 1979). Its energy potential is determined by water drive and gas drive regimes. The main of the prevailing issues is the rapid pace and the scale of production becoming water-cut. Productive suite, that is mainly built with tuff, is anisotropic due to numerous parameters. Respectively, intervals and sections with high and low-filtration properties are identified in the geological cross-section. In addition, the producer well coverage is not dense enough and undeveloped oil-bearing zones (lenses) remain in the spaces between the wells. All of the above indicates that the field is unevenly developed, and certain oil reserves are remaining there. In the period of 2000-2006 and since 2015 the methods of horizontal well drilling and injection of technical water into the productive layer were applied to increase the oil recovery factor. In the result, production (oil and gas) noticeably increased. Application of the complex hydrodynamic methods in the future will enable us to significantly increase the remaining oil production from the stratigraphically lower, water-cut horizons of the productive suite.

Death Anxiety and Depression among Cancer Patients: Role of Perceived Social Support

The primary objective of this study was to investigate the relationship between death anxiety and depression in individuals coping with cancer, focusing specifically on the role of perceived social support as a protective factor. The sample consisted of 200 cancer patients (95 males, 105 females) from hospitals in Rawalpindi and Islamabad, spanning different age groups. Data were categorized by cancer stage and treatment types. Using a cross-sectional design and correlational approach, the study found excellent reliabilities for Perceived Social Support (? = .90) and good reliabilities for Depression and Death Anxiety (? = .83 and .85, respectively). Gender-based differences were not significant for depression (t = -.51, p > .05) or perceived social support (t = -.23, p > .05). Perceived social support was highest initially and declined as cancer progressed. Significant variance in social support was observed across cancer stages (p < .05), with post hoc tests showing that 1st stage patients had significantly higher support than 2nd, 3rd, and 4th stage patients (MD = 7.27, p = 0.09). The study also showed gender differences in death anxiety, suggesting that women exhibited higher levels of death anxiety compared to men. Moreover, perceived social support was high at the 1st stage and significantly declined as the level progressed (3rd stage). The findings can be helpful for health professionals, psychologists and caregivers.

Exploring Malnutrition Risk in Cancer Chemotherapy Patients: An Assessment of Associated Factors in a Tertiary Care Cancer Center

Objectives: This study aimed to assess the risk of malnutrition in cancer chemotherapy patients and identify the associated factors. Materials and Methods: It is a cross-sectional study. Purposive sampling was used to collect data from a tertiary care cancer centre. The study collected data from 101 participants and used a malnutrition screening tool (MST) to assess the risk of malnutrition. Results: The majority of participants in the study were female (61.4%) and in the 3rd or 4th stage of cancer (57.4% and 41.6%, respectively). Of the participants, 63.4% experienced weight loss without trying chemotherapy, and 60.4% were at risk for malnutrition. Cancer stage was associated with malnutrition risk, but other clinical variables were not. Conclusion: Malnutrition is a significant issue among cancer chemotherapy patients in the study’s population. The findings of this study can be used to develop interventions to prevent and manage malnutrition in patients with cancer and improve the effectiveness of cancer treatment in the Indian population.

BEARING CAPACITY, DEFORMITY AND CRACK RESISTANCE OF DAMAGED BEAMS REINFORCED WITH FIBER CONCRETE

The results of experimental studies of the load-bearing capacity, deformability and crack resistance of damaged beams reinforced with fiber concrete in the compressed and stretched zone are presented. Test samples are made of concrete and fiber concrete. The amount of steel fiber in fiber concrete is 2% of the volume of the product. Preliminary tests were carried out on prisms and cubes. During the manufacture of beam samples, before concreting, a foam insert was installed in the area of planned damage, the shape and dimensions of which corresponded to the damage. After the concrete set to 70% grade strength, the liner was pulled out, and the resulting cavity was filled with a 2% mixture of fiber concrete. Tests of material samples showed that the introduction of steel fiber into the composition of concrete in the amount of 2% by volume increases the compressive strength limit by 15.3%. The initial modulus of elasticity of fiber concrete of the specified mixture is 38.0% higher than that of ordinary concrete of this composition. Conducted experimental studies of damaged beams showed that a beam whose cross-section is 40% damaged in the middle-compressed zone, and the shape of the damage is close to rectangular, has a load-bearing capacity of 92.0 kN, or 93.9% of the load-bearing capacity of an undamaged beam. Cracking started at the 4th loading stage, when the load value was 26.0kN, i.e. 28.3% of the bearing capacity of the damaged beam. The maximum final crack opening width was 0.6 mm. A beam whose section is 40% damaged in the mid-stretch zone has a load-bearing capacity of 92.4 kN, or 93.2% of the load-bearing capacity of an undamaged beam. Cracking started at the 5th loading stage, when the load was 32.5kN, i.e. 35.2% of the bearing capacity of the damaged beam. The maximum final crack opening width was 0.8 mm. It is claimed that the strengthening of a beam with 40% damage in the compressed or stretched zone in the manner considered in the paper is effective, as it allows achieving its load-bearing capacity, which is more than 93% of the load-bearing capacity of an undamaged beam.

Shading and waterlogging interactions exacerbate summer maize yield losses by reducing assimilate accumulation and remobilization processes

Persistent overcast rain was an essential limiting factor for summer maize production, of which immediate impact was the dual pressure of waterlogging and shading. However, the mechanism of independent and combined effects of waterlogging and shading induced maize yield losses are rarely studied, especially at different growth stages. Denghai 605 (DH605) was selected to be subjected shading, waterlogging, and their combined stress at the 3rd leaf stage (V3), the 6th leaf stage (V6), and tasseling stage (VT). Results showed that shading, waterlogging and their combination significantly limited the expansion of leaf area, and decreased leaf net photosynthetic rate (Pn) and net assimilation rate (NAR), thus reducing the crop growth rate (CGR) and biomass accumulation. At the same time, compared to control, the process of lignin synthesis was inhibited under stressed treatment, resulting in reduced stem mechanical strength and a poor development of the vascular system, of which change significantly reduced efficiency of assimilate remobilization to the ear and ultimately grain yield. The most significant effects of waterlogging and combined stresses on yield were occurred at V3 stage, followed by the V6 and VT stages. The most significant effects of shading were occurred at VT stage, followed by the V6 and V3 stages. Moreover, the compound stress exacerbated the damage brought about by a single stress. It is predicted that climate change will increase the frequency of abiotic stress assemblages, and the results of these findings provide some direction for further research on maize breeding in summer maize under continuous rainy conditions in the future.

Patient centric factors affecting delay in self-diagnosis and seeking medical care for oral cancer: a cross-sectional study

Background: Oral cancer is often detected in the advanced stage, with a low survival rate of 5 years and with increase in mortality which, affects patient quality of life. The early diagnosis would reduce the mortality rate and morbidity rate, by bringing a change in the quality of life. Methods: The study utilized convenient sampling method to select the participants. Participants who were diagnosed with oral cancer currently at 3rd and 4th stage. Data collection was done using pre-validated self-administered questionnaire, which was provided to the participants through Google forms. Results: The study demonstrated 43.1% people diagnosed with stage-3 oral cancer had an average delay of 34.6 months and 26% of stage-4 cancer patient had an average delay of 59.9 months to their first visit to treatment center. In this study 34% of the study participants were unaware and had lack of knowledge about oral cancer related symptoms. Self-medications/herbal medications, fear for the treatment, socio-economic factors, COVID-19/ lockdown restriction were also other reasons reported by patients. Conclusions: The prompt treatment is necessary in both advanced cases and early cases of oral cancer. Radiotherapy, chemotherapy, and surgery are all part of the treatment when given timely. Thus, early diagnosis plays a vital role in saving many live.

An Analysis of Medical Students’ Learning Experiences in Small Group-Based Teaching in Kurdistan Region-Iraq

Objective: This study aims to evaluate the learning styles, activities, and experiences of medical students within the context of small groupbased teaching in the Kurdistan Region of Iraq. Methods: A cross-sectional study was conducted between February and May 2022 at Zakho College of Medicine, involving students from various medical colleges in the region. A pre-designed questionnaire was administered both in-person and online. Comprising two main parts in addition to demographic information, the questionnaire assessed students' learning styles based on O'Brien's modality learning channel preference and their preferences and experiences in small-group settings. Results: The sample included students from the 1st to the 5th stage, totaling around 400 participants. The cohort was predominantly female (60.05%) and largely from the 2nd stage of medical education (55.03%). Visual Learning was the most common learning style, particularly among female students. Significant variations in learning styles were noted across different academic stages and universities. Small-group activities and formative assessments were generally favored. While most students were either "satisfied" or found it "natural" concerning group size, dissatisfaction was prominent regarding available teaching resources. Statistical analyses confirmed significant differences in learning styles, preferred teaching methods, and feelings about the learning environment. Conclusion: The study offers critical insights into the diverse learning preferences and experiences of medical students in small-group settings. Despite a general preference for Visual Learning and small-group activities, significant variations exist, warranting a nuanced approach to educational strategy. Given the diverse learning preferences and significant dissatisfaction with available resources, a multifaceted educational approach is recommended, including diverse teaching and assessment methods and increased investment in teaching resources.

BEARING CAPACITY, DEFORMABILITY AND CRACK RESISTANCE OF A DAMAGED BEAM REINFORCED WITH FIBER CONCRETE IN THE COMPRESSED ZONE

The paper presents the results of the study of the load-bearing capacity, deformability and crack resistance of a damaged beam reinforced with fiber concrete in the compressed zone. A beam with 40% damage is considered. The research was conducted in two stages. At the first stage, tests of prisms and cubes made of concrete and fiber concrete were carried out, which showed that the introduction of steel fiber into the composition of concrete in the amount of 2% by volume increases the compressive strength by 15.3%. The initial modulus of elasticity of fiber concrete of the specified mixture is 38.0% higher than that of ordinary concrete of this composition. According to the results of experimental studies of prisms, a diagram of concrete deformation, the nature of changes in relative linear deformations of fiber concrete, as well as graphs showing a comparison of the nature of deformation of concrete and fiber concrete were constructed. At the second stage, the beam sample was tested on a specially designed stand. Before concreting, a foam insert was installed in the zone of planned damage, the shape and dimensions of which corresponded to the planned damage. After the concrete set to 70% strength, the liner was removed, and the formed cavity was filled with a 2% fiber concrete mixture. A beam with 40% cross-sectional damage in the mid-compression zone and a near-rectangular damage shape was found to have a load-bearing capacity of 92.0 kN, or 93.9% of the load-bearing capacity of an undamaged beam. Cracking started at the 4th loading stage, when the load value was 26.0kN, i.e. 28.3% of the bearing capacity of the damaged beam. At the same time, 5 cracks formed in the area of pure bending. At the fifth stage, two more cracks appeared. At the 8th and 9th loading stages, 4 more cracks formed. A total of 12 cracks were formed. The maximum final crack opening width was 0.6 mm. Thus, the strengthening of a beam with 40% damage in the compressed zone by the method considered in the work allows you to achieve its bearing capacity, which is 93.9% of the bearing capacity of an intact beam.

A Compact THz Photometer for Solar Flare Burst Studies from Space

Recent solar flare observations reveal the presence of THz components having a few orders of magnitude higher amplitude than the Radio Frequency (RF) and microwave radiations in the solar flare spectrum. This feature makes it remarkably beneficial for the detection of solar flares of low magnitudes such as Geostationary Operational Environmental Satellite (GOES) Class C, and M flares. Hence, space agencies including National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) are gearing up with THz instruments for solar flare observations. In line with this, Laboratory for Electro-Optics Systems (LEOS) has completed the development of a photometer that operates in continuum THz band, from 1.5 to 15 THz. The entire electro-opto-mechanical design was carried out to realize a compact, light-weight and power-efficient photometer to meet the size, mass and power constraints posed by inherent resource limitations of experimental satellite platforms such as Nanosatellite, Microsatellite and Polar Satellite Launch Vehicle’s 4th Stage Orbital Platform (PS4-OP). A Cassegrain optical configuration was designed to collect the sun radiation with an aperture effective area of 0.0027 m2 with ceramic low pass filters and resonant mesh filter for selective perception of THz radiation, rejecting the huge background of visible and Near Infrared (NIR) with a spectral selectivity of 107:1. Sensitivity of the Photometer was estimated to be 41.5 K/mV in 1.5 to 15 THz band by calibration using a blackbody radiation source. The radiometric resolution of the payload is 125 Solar Flux Unit (SFU) (1 SFU=1×10-22 Wm-2Hz-1). The payload was successfully developed and space-qualified for its deployment in Nanosatellite or PS4-OP platform.