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Quercus pubescens Willd. is a deciduous species that can retain leaves in the winter either as dead, standing leaves (marcescence), or as living, winter-green leaves. The retention of green leaves through winter is rare in continental areas. Winter-green leaves were observed on one-year-old seedlings of Q. pubescens in the winter of 2020 in the nursery of the Faculty of Forestry that lasted until the end of April 2021. The photosynthetic activity of photosystem II was measured using the rapid light curve method based on modulated pulse chlorophyll fluorescence. We assessed the potential photosynthetic activity of the leaves across the range of physiological stages: winter-green leaves retained from the previous growing season and on the leaves from the first, second, and third growth flush during the growing season. Photosystem II of winter-green leaves attained ~50-60% of the maximal photosynthetic activity obtained in spring and summer leaves, respectively. Climate data indicated that winter-green leaves exhibited frost resistance in the winter of 2020/2021, as their photosynthetic activity was preserved despite 33 days with sub-zero temperatures. The rapid light curve method also revealed the gradual acclimation of seedlings on a flush level, with leaves from the third flush best able to use available light under high temperatures and insolation efficiently. The results of rapid light use as an indicator of seedling acclimation are discussed. Some remarks on the possible practical significance of the winter-green leaves phenomenon (as in genetic selection) are highlighted.

Growth elements and stand structure of an artificially established Norway spruce stand were presented at age 37 and 62-yr on the basis of a single permanent sample plot and their changes analyzed. The stand was established with 4500 seedlings per hectare. At age 37-yr on the permanent sample plot, 2600 trees per hectare were recorded with basal area of 43.52 m2•ha−1 and standing volume of 319,97 m3•ha−1. At stand age 62-yr, 878 trees per hectare were recorded with basal area of 42.61 m2•ha−1 and standing volume of 454,48 m3•ha−1. First selective thinning, conducted at mean aspirant’s height of 17.6 m (500 trees per hectare) at age 37-yr was characterized as a moderate (28.3% trees per hectare and 23.5% volume thinned) thinning from below (qd = 0.88). Out of the remaining number of trees (1823 per hectare), in the following period between 38-62-yr, 956 trees per hectare (52.4%) were removed, mostly through sanitary cutting that can be characterized as thinning from below (qd = 0.68). Out of the initially selected aspirants at age 37-yr, 220 elite trees were selected at age 62-yr due to the effects of self-thinning in the stand and unfavorable exogenous factors as well as the thinning from below regime. At age 62-yr, the stand structure is unfavorable and statically unstable as the slenderness coefficient is increased compared to the condition at 37-yr. Thus, it can be concluded that the risk for achieving the productive and meliorative potentials of the stand is increased, primarily due to absence of adequate maintenance of the stand between age 38 and 62-yr.

The application of silviculture measures on contemporary, rationalized basis in order to sustain and improve forests in the area of the National park „Fruška Gora”, is the most im­portant segment of forest management, having in mind their anthropogenically deteriorated conditions and their purpose. For the improvement of stand conditions, intensive silvicultural tending measures are necessary in certain phases of development of the stands which is con­trary to the passive protection. The main reasons for the application of these measures are in the coppice origin of the stands on over 82% of the area of National park and the silver lime dominance compared to other edificators (oaks and beech). On the basis of the ecosystem approach in forest management, and especially in conditions of more pronounced climate change, the silvicultural measures need to be rationally synchronized with biological-ecological demands of the main species and dominant processes in forest ecosystems. In other words, there is a need to implement the elements of close-to-nature forest management. This paper points toward the most important determinations of silviculture in order to achieve the goals of special-purpose forests in the National park.

Stand structure analysis was conducted before and after natural regeneration (on the same plot) on a site of monodominant sessile oak forest (Quercetum petraeae Čer. et Jov. 1953., subass. tilietosum). In this stage individual old sessile oak trees were still remaining in the stand. Before the regeneration in the 150-yr-old stand in 1992 only sessile oak was rep­resented in the upperstorey. The trees mostly had irregularly developed crowns and reduced growth potential. These were the elements used in planning the regeneration in management plans. Besides the remaining individual old sessile oak trees, silver lime dominates in the young stand in 2017. In the stand structure there is no biological potential of sessile oak trees that could represent the basis for further development because the sessile oak trees are suppressed by silver lime towards the understorey and even the herb layer. Because of the undefined significance of the silver lime in the stand, transient management was prescribed in the man­agement plan so a reconstrucion of the stand should follow in one of the next management periods in order to restore sessile oak on the site as it was suppressed due to an inedequate regeneration procedure. On the basis of the studied stand structure of the young stand, the abandonment of the transient management concept is recommended and introduction of the intensive management approach of slver lime in the current rotation. This was based on the available number of silver lime trees of good quality in the stand, i.e. the aspirants for tending by means of selective thinning and their strong growth response four years after selective thinning. Old sessile oak trees that are still present in the stand are only a simulacrum of the continuity of the current stand with the previous one and they should be removed by means of intensive and rationalized tending of silver lime, and partly integrated in the silver lime stand.

The paper analyzes the elements of the stand structure and proposes silvicultural measures to improve conditions in the stand of black locust (Robinia pseudoacacia L.) and common hackberry (Celtis occidentalis L.) aged 28 years in Subotica-Horgoš sands. The research was performed on three permanent experimental plots on which selective thinning (T1 and T2) was performed experimentally in two plots, while one was left as a control plot (C).Initially, 528 trees for tending per hectare were selected in the studied age, of which 448 black locust and 80 common hackberry trees per hectare were selected on T1, and 320 black locust and 208 common hackberry trees per hectare on T2.In experimental plots T1 and T2 at least one competing tree was cut down to each tree for tending, and a total of 912 and 1072 trees were cut down per hectare with a total volume of 53-55 m3∙ha−1.In this way, a basis was created for the assessment of the growth response of trees to selective thinning in the upcoming period.

The paper presents the methodology and classification of pile integrity and load testing, in compliance with current foreign standards, as well as our own defined segments of standard improvement and our own definitions of certain key elements. The classification has been conducted according to the test types which clearly define the pile testing process, analysis methods, and test results processing. Beside the basic division of pile testing to integrity tests and load tests, there is also an additionally defined group of shaft control tests in the case of bored piles, since for the proper shaft formation, when it comes to bored piles, certain qualitative-quantitative criteria must be fulfilled beforehand. Presented in this way, the methodology and classification of pile integrity and load tests serves, primarily, an educational purpose for civil and geotechnics engineers who deal with this issue, to additionally introduce innovations in this field of testing and clarify all the elements of the testing since contradictory opinions and disagreements regarding the testing details are quite common in practice.

The paper presents typical examples of pile integrity testing and the results analysis, whereby the testing methodology relies on existing ASTM standards, as well as on the testing methodology presented in the scientific paper Pile Integrity and Load Testing: Methodology and Classification, published in this journal. The pile tests were conducted using licensed equipment for Sonic Integrity Test (SIT) and Crosshole Sonic Logging (CSL). The tests have shown the correct and problematic situations that arise when analyzing pile integrity. Some aspects of the wave theory implementation, but also of signal processing and numerical analysis have been indicated. Also, the need to develop a plan for testing the integrity of piles in structures with a large number of piles has been emphasized.

This paper presents the structure of well-preserved, mature stands of seed origin and young stands that followed either after planned regeneration or spontaneously in the understory reinitiation stage, in monodominant sessile oak forests (Quercetum petraeae Čer. et Jov. 1953.) from two subassociations, tilietosum and typicum, in the territory of „Đerdap” National Park. The presentation of mature stands is based on the data collected from experimental plots in 1992, in the period characterized by the mass occurrence of sessile oak decline in this area, and across Europe. The stands were around 150 years old in 1992, and consisted only of sessile oak in the tree layer. The canopy closure of the stands was 0.7-0.8, with a large standing volume. There were no major differences between the stands regarding social classes, stem quality, crown development and crown condition. The presentation of young stands is based on the data collected in 2017 from a permanent experimental plot, as well as on the data from other authors. The structure of young stands indicates that different silvicultural measures need to be planned during the regeneration stage for different subassociations of the monodominant sessile oak forest in order to reach sufficient natural regeneration of sessile oak. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR31041, Grant no. III43007 and Grant no. III43010]

According to the analysis of a large number of scientific papers, the authors of the paper presented their own original systematization of the analytical and numerical methods of landslide stability calculation, with a large part of them still to be further improved, implemented and tested on complex 3D landslide models. Methods for calculating the stability of the landslide are classified into five groups: analytical single-step, analytical multi-step (iterations of sliding surfaces), numerical multi-step (iterations of sliding surfaces), numerical incremental-iterative (nonlinear) analysis and numerical incremental-iterative (nonlinear) analysis, applying numerical integration in the time domain. By using the systematization method of calculating the stability of the landslide it can be very effective to consider which type of method is optimal for landslide analysis and which type of method should be considered in the phase of preliminary and final analysis for scientific research and expert projects.

The paper studies the effects of two heavy selection thinnings on the increment of Norway spruce trees exposed to ice and snow breaks in eastern Serbia. In a thinning that was carried out at 32 years of age, 556 candidates per hectare were selected for tending, and at the age of 40, of the initial candidates, 311 trees per hectare (55.9%) were selected as future trees. In all trees at 41-50 age period, diameter increment was higher by 31%, basal area increment by 64% and volume increment by 67% compared to 32-40 age period. The collective of indifferent trees is significantly falling behind compared to future trees in terms of increment values in both observed periods. However, the value of diameter, basal area and volume increments, of the collective of "comparable" indifferent trees are lower in comparison to the values of increments of future trees by 10-15% in the 32-40 age period, and by 15-21% in the 41-50 age period and there are no significant differences. The results show that heavy selective thinnings, initially directed at a larger number of candidates for tending at stand age that does not differ much from the period of carrying out first "commercial" thinnings, improve the growth potential of future and indifferent trees, where it is rational to do the tree replacement for the final crop in "susceptible" growth stage to snow and ice breaks. [ Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 43007: Studying climate change and its influence on the environment: impacts, adaptation and mitigation]

The paper presents the occurrence of subspontaneous dispersal of Kentucky coffeetree in the park-forest which is a part of a protected natural area "Topčiderski park" in Belgrade. In 1949, three trees of Kentucky coffeetree not older than 85 years were recorded. In 2016, one sexually reproductive tree was recorded in Topčider which is assumed to be one of the three "mother" trees recorded in 1949. The diameter at breast height is 94.6 cm and the height of the tree is 24.1 m. During the past seven decades, the Kentucky coffeetree regenerated successfully from seed and root suckers in the area that was under anthropogenic influence and was left to succession, but the Kentucky coffeetree has not shown invasiveness. In the area of subspontaneous dispersal of Kentucky coffeetree (0.25 ha), all the trees that had diameter at breast height 1.0 cm and more were measured. Fourteen tree and shrub species were identified with a total of 624 trees and Kentucky coffeetree was the most represented species with 326 trees (52.2%). In the subspontaneous regenerated group of Kentucky coffeetree, the diameter at breast height of the thickest tree is 48.2 cm and the highest tree is 25.5 m tall. The diameter structure of Kentucky coffeetree trees shows the declining distribution. Compared to the habitus of "mother" tree, that has a slenderness of 25, the habitus of the dominant and codominant trees in the subspontaneous regenereted group of Kentucky coffeetree is characterized by slenderness of 75-110 that is characteristic of the trees grown in the stand closure.

Sex differences in immune responses impact cancer outcomes and treatment response, including in glioblastoma (GBM). However, host factors underlying sex specific immune-cancer interactions are poorly understood. Here, we identify the neurotransmitter γ-aminobutyric acid (GABA) as a driver of GBM-promoting immune response in females. We demonstrated that GABA receptor B (GABBR) signaling enhances L-Arginine metabolism and nitric oxide synthase 2 (NOS2) expression in female granulocytic myeloid-derived suppressor cells (gMDSCs). GABBR agonist and GABA analog promoted GBM growth in females in an immune-dependent manner, while GABBR inhibition reduces gMDSC NOS2 production and extends survival only in females. Furthermore, female GBM patients have enriched GABA transcriptional signatures compared to males, and the use of GABA analogs in GBM patients is associated with worse short-term outcomes only in females. Collectively, these results highlight that GABA modulates anti-tumor immune response in a sex-specific manner, supporting future assessment of GABA pathway inhibitors as part of immunotherapy approaches., Competing Interests: Conflict of interest: In the past three years, C.A.L. has consulted for Astellas Pharmaceuticals, Odyssey Therapeutics, Third Rock Ventures, and T-Knife Therapeutics, and is an inventor on patents pertaining to Kras regulated metabolic pathways, redox control pathways in pancreatic cancer, and targeting the GOT1-ME1 pathway as a therapeutic approach (US Patent No: 2015126580-A1, 05/07/2015; US Patent No: 20190136238, 05/09/2019; International Patent No: WO2013177426-A2, 04/23/2015). J.D.L reports being named as a co-inventor on pending and issued patents held by the Cleveland Clinic relating to cancer therapies, but these are not directly relevant to this work.

Objective: Outpatient surgery and same-day discharge are developing fields that align with the evolving needs of modern healthcare, presenting a notable advantage by reducing patient susceptibility to nosocomial infections, thromboembolic complications, and medical errors. When paired with enhanced recovery after surgery protocols, they hold promise in safely transitioning certain patients undergoing cranial surgery to outpatient care. This study aimed to evaluate discharge on the same day of surgery after intracranial tumor resection and endoscopic third ventriculostomy (ETV) and to investigate potential associations with anesthesia methods, complications, and readmission rates., Methods: A retrospective analysis of patients scheduled for planned discharge on the same day of surgery between August 2020 and October 2023 was conducted. Data included patient demographic characteristics, preoperative clinical deficits, diagnosis, findings on preoperative and postoperative MRI, lesion characteristics, complications, and readmission rates., Results: A total of 202 patients were included in the study. The mean age was 56.8 years and 117 (57.9%) patients were female. Patients were admitted the evening before surgery to obtain preoperative clearance and undergo MRI. The most common diagnoses were metastasis (23.3%), meningioma (20.8%), glioblastoma (12.4%), and low-grade glioma (10.4%). Craniotomy (46.5%), stereotactic needle biopsy (35.1), and ETV (6.9%) were the most common procedures performed. Thirteen (6.4%) patients underwent awake craniotomy, and 189 (93.6%) surgical procedures were conducted under general anesthesia. Complications occurred in 1.5% of patients, with no permanent complications observed during a mean follow-up of 9.3 months. In total, 179 (88.6%) patients were successfully discharged on the same day of surgery. The median length of hospitalization was 26.8 hours, with the median length of postoperative stay being 7 hours. Twenty-three (11.4%) patients were deemed ineligible for discharge on postoperative day 0 and instead discharged on postoperative day 1. The reasons for these delays included further clinical monitoring (n = 12), social factors (n = 4), and patient preference (n = 7). Age was positively correlated with length of hospitalization (p = 0.006). In total, 6.4% of patients were readmitted within 1-30 days after discharge, with 2.5% readmitted to the department of neurosurgery., Conclusions: This study demonstrates the safety and feasibility of discharge on the same day of surgery, with a high success rate and low complication rates. Early discharge did not increase morbidity or readmission rates. Implementation of clear discharge protocols and thorough patient education are crucial for successful same-day discharge programs in neurosurgery.