Buildup Of Debris Research Articles

A review of global long-term changes in the mesosphere, thermosphere and ionosphere: A starting point for inclusion in (semi-) empirical models

The climate of the upper atmosphere, including the mesosphere, thermosphere and ionosphere, is changing. As data records are much more limited than in the lower atmosphere and solar variability becomes increasingly dominant at higher altitudes, accurate trend detection and attribution is not straightforward. Nonetheless, observations reliably indicate that, on average, the mesosphere has been cooling, the density in the thermosphere has been decreasing, and ionospheric layers have been shifting down. These global mean changes can be largely attributed to the increase in CO2 concentration, which causes cooling and thermal contraction in the middle and upper atmosphere. The decline in thermosphere density is particularly relevant from a practical viewpoint, as this reduces atmospheric drag and thereby increases orbital lifetimes and the build-up of space debris. Long-term changes in the ionosphere can have further practical implications and are not only driven by the increase in CO2 concentration, but also by changes in the Earth’s magnetic field. The empirical models that are mostly used to inform applications in industry on the state of the upper atmosphere, as well as being widely used in science, do not yet properly account for long-term trends in the mesosphere, thermosphere and ionosphere. This is problematic when long-term future projections are needed or models rely strongly on older data. This review provides an overview of the main evidence of long-term trends observed in the mesosphere, thermosphere and ionosphere, together with the latest insights on what causes these trends. It is hoped that this may serve as a starting point to include long-term trends in (semi-) empirical models to benefit all users of these models. We also offer some thoughts on how this could be approached.

Glia multitask to compensate for neighboring glial cell dysfunction.

As glia mature, they undergo glial tiling to abut one another without invading each other's boundaries. Upon the loss of the secreted neurotrophin Spätzle3 (Spz3), Drosophila cortex glia transform morphologically and lose their intricate interactions with neurons and surrounding glial subtypes. Here, we reveal that all neighboring glial cell types (astrocytes, ensheathing glia, and subperineurial glia) react by extending processes into the previous cortex glial territory to compensate for lost cortex glial function and reduce the buildup of neuronal debris. However, the loss of Spz3 alone is not sufficient for glia to cross their natural borders, as blocking CNS growth via nutrient-restriction blocks the aberrant infiltration induced by the loss of Spz3. Surprisingly, even when these neighboring glia divert their cellular resources beyond their typical borders to take on new compensatory roles, they are able to multitask to continue to preserve their own normal functions to maintain CNS homeostasis.

Inflammation and Macrophage Loss Mark Increased Susceptibility in a Genetic Model of Acute Viral Infection-Induced Tissue Damage.

M.R2k/b mice are identical to the MA/My parent strain aside from a 5.58-Mb C57L-derived region on chromosome 17 (Cmv5s) that causes increased susceptibility to acute murine CMV (MCMV) infection and the development of significant spleen tissue damage. Spleen pathology begins at the marginal zone (MZ), apparent by 2 d postinfection (dpi), and progresses throughout the red pulp by 4 dpi. To better understand how M.R2k/b mice respond to infection and how Cmv5s contributes to tissue damage in the spleen, we assessed the regulation of myeloid cells and inflammation during acute MCMV infection in MA/My and M.R2k/b mice. We found that Cmv5s drove increased neutrophil accumulation and cell death at the MZ, which corresponded with evidence of localized oxidative stress and increased overall spleen IL-6 and TGF-β1 early during infection. Further assessment of MCMV infection dynamics at the early MZ revealed infected SIGNR1+ MZ macrophages as the first apparent cell type lost during infection in these mice and the likely target of early neutrophil recruitment. Spleen macrophages were also identified as the mediators of differential spleen IL-6 and TGF-β1 between MA/My and M.R2k/b mice. Interrogation of MCMV progression past 2 dpi revealed substantial M.R2k/b F480+ red pulp macrophage loss along with buildup of oxidative stress and MZ macrophage debris that was not neutrophil dependent. Together we identify Cmv5s-driven macrophage loss and inflammation during acute MCMV infection corresponding with the spatial and temporal development of spleen tissue damage.

Effect of High-Density Packing Recycled Aggregate on Concrete Strength Properties

As many residential homes and structures were destroyed or badly damaged because of the military battle in Iraq, it is critical to recycle construction debris widely in the rebuilding and decoration of buildings and infrastructure. This battle resulted in the buildup of massive construction debris, and recycling this waste allows for a cleaner environment. Recycling the construction waste of various installations is an urgent need to decrease the consumption of natural materials and landfills of construction waste, and as a result reduce the environmental pollution. Therefore, this study is a local focus on using concrete debris to obtain high packing density recycled coarse and fine aggregates in various fractions of (0.16 mm - 10 mm) by selecting high-density packing materials that was developed by Kharkhadin A.N in laboratories of Belgorod State Technical University in Russia to preparing of reference mix from ordinary density recycled aggregate. The new concrete samples for two concrete mixtures were prepared, to identify and study the important specifications. Models of cubes and standard prisms were prepared to evaluate the compressive strength and the splitting tensile strength. Also, the modulus of rupture and the unit weight were conducted. The results indicated an increase in the concrete’s mechanical properties using the high-packing density recycled aggregate. The obtained compressive strength, splitting tensile strength and modulus of rupture were (49) MPa, (3.6) MPa, and (7.1) MPa compared with a reference mix (39) MPa, (3.3) MPa and (6.3) MPa, respectively. The reference mix corresponding properties were (39) MPa, (3.3) MPa, and (6.3) MPa, respectively. Also the values of an oven-dry density were (2340) kg/m3 compared with the reference mix (2260kg/m³). These results proved that increasing the packing density of recycled aggregate enhanced the concrete’s strength properties.

Debris Index Before and After Apple Consumption

Dental caries is a form of tooth decay that begins in the enamel and progresses to the dentin. This is usually caused by poor oral hygiene, which causes a buildup of debris that harbors various types of bacteria. Efforts to prevent debris accumulation can be in the form of mechanical control, chemical control and control of fibrous foods such as apples Purpose: The purpose of this study was to analyze the effectiveness of the debris index before and after consuming apples. Methods: The type of research used in this study was a quasy experiment with a pretest and posttest design with one group design. This research was conducted with a sample of 84 students, using a total sampling technique, the research data used primary data. The research instrument uses a debris index check sheet. Data analysis was tested using paired sample t test. Results: Before entering the apples, 14 students (16.7%) had good debris criteria, 66 students (78.6%) had moderate debris criteria and 4 students (4,8%). And after consuming apples, 77 students (91.7%) had good debris criteria index, 7 students (8.3%) had moderate debris criteria index and no students had bad debris criteria index. Conclusion: The Debris Index before consuming apples was highest in the Moderate mixture of 66 students (78.6%). The Debris index after consuming apples was the highest in a good assessment of 77 students (91.7% and there were no bad criteria of 0.0%, the number of students who consumed apples was 86.9%, the highest with a good assessment of (91.7%), with the results of paired sample t-test p<0.001. Conclusion: Consuming apples is effective in reducing the debris index.

Purification of Water Using Nanotechnology

One of the most crucial ingredients for life on earth is water. It has played a crucial role in the development of human civilizations, starting with the emergence of the first aspect of existence in seawater. The demand for clean water is universal and essential to all human species. But at the moment, pure water supplies are being poisoned. Water quality and society's level of development have recently been linked. The safety of drinking water has been put in jeopardy by several chemical and biological pollutants. Alternatives for decontaminating and reusing water are among the most desired solutions to address the issues of water shortage and the escalating disputes over this essential resource. A significant issue is the buildup of organic debris and its residues in wastewater. Significant progress has been achieved in using the chemistry of nano-materials for purifying water as a result of the realization of the molecular nature of pollution in drinking water. Due to its capacity to produce precise, structurally controlled materials for such needs, nanotechnology offers exceptional potential in filtering applications. By extending the idea of clean, inexpensive, and sustainable water to the ecosystem as a whole, we point out that cities may live and breathe comfortably by using such technology. Sustainability in clean water may be achieved by comprehending the major environmental issues facing the world and investigating potential solutions from new nanotechnologies.

Environmental Displacement in the Anthropocene

This intervention invites more substantial scholarly attention to human displacement in and of the Anthropocene—this current epoch in which humans have become the primary drivers of global environmental change—and sets out an initial framework for its study. The framework is organized around three interrelated contributions. First is the recognition that displacement is driven not just by climate change but also broader forms of environmental change defining the Anthropocene, including biodiversity loss, changes to land and water resources, and the buildup of nuclear debris, along with their intersections. Second, the framework parses out three distinct moments of displacement in the Anthropocene: displacement as a consequence of, prerequisite to, and active response to environmental change. Third, the framework rejects environmental (neo)determinism by showing how displacement across these distinct moments and drivers is more than environmental: It is the articulation of environmental and sociopolitical–economic factors, which are routinely shaped by inequality and play out within a broader series of crises and crisis narratives that drive displacement and hinder viable solutions. We ground these interventions in examples of political conflict, anti-immigrant politics, the posttruth and colonial politics of knowledge production, and the Anthropocene itself as crisis requiring displacement to clean up its mess. Although each example is quite distinct, a common thread stitched across them is colonialism, highlighting a recurring extra-environmental driver of displacement. Taken together, these dynamics underscore that displacement is not an unfortunate by-product of the Anthropocene but woven into its very fabric.

Lipid-Bicelle-Coated Microfluidics for Intracellular Delivery with Reduced Fouling.

Innovative technologies for intracellular delivery are ushering in a new era for gene editing, enabling the utilization of a patient's own cells for stem cell and immunotherapies. In particular, cell-squeezing platforms provide unconventional forms of intracellular delivery, deforming cells through microfluidic constrictions to generate transient pores and to enable effective diffusion of biomolecular cargo. While these devices are promising gene-editing platforms, they require frequent maintenance due to the accumulation of cellular debris, limiting their potential for reaching the throughputs necessary for scalable cellular therapies. As these cell-squeezing technologies are improved, there is a need to develop next-generation platforms with higher throughput and longer lifespan, importantly, avoiding the buildup of cell debris and thus channel clogging. Here, we report a versatile strategy to coat the channels of microfluidic devices with lipid bilayers based on noncovalent lipid bicelle technology, which led to substantial improvements in reducing cell adhesion and protein adsorption. The antifouling properties of the lipid bilayer coating were evaluated, including membrane uniformity, passivation against nonspecific protein adsorption, and inhibition of cell attachment against multiple cell types. This surface functionalization approach was applied to coat constricted microfluidic channels for the intracellular delivery of fluorescently labeled dextran and plasmid DNA, demonstrating significant reductions in the accumulation of cell debris. Taken together, our work demonstrates that lipid bicelles are a useful tool to fabricate antifouling lipid bilayer coatings in cell-squeezing devices, resulting in reduced nonspecific fouling and cell clogging to improve performance.

Orbital-use fees could more than quadruple the value of the space industry

The space industry's rapid recent growth represents the latest tragedy of the commons. Satellites launched into orbit contribute to-and risk damage from-a growing buildup of space debris and other satellites. Collision risk from this orbital congestion is costly to satellite operators. Technological and managerial solutions-such as active debris removal or end-of-life satellite deorbit guidelines-are currently being explored by regulatory authorities. However, none of these approaches address the underlying incentive problem: satellite operators do not account for costs they impose on each other via collision risk. Here, we show that an internationally harmonized orbital-use fee can correct these incentives and substantially increase the value of the space industry. We construct and analyze a coupled physical-economic model of commercial launches and debris accumulation in low-Earth orbit. Similar to carbon taxes, our model projects an optimal fee that rises at a rate of 14% per year, equal to roughly $235,000 per satellite-year in 2040. The long-run value of the satellite industry would more than quadruple by 2040-increasing from around $600 billion under business as usual to around $3 trillion. In contrast, we project that purely technological solutions are unlikely to fully address the problem of orbital congestion. Indeed, we find debris removal sometimes worsens economic damages from congestion by increasing launch incentives. In other sectors, addressing the tragedy of the commons has often been a game of catch-up with substantial social costs. The infant space industry can avert these costs before they escalate.

Characterization of flowing liquid films as a regenerating plasma mirror for high repetition-rate laser contrast enhancement

AbstractIn this paper, we characterize a high repetition-rate regenerating plasma mirror produced by the thin film of liquid formed when two laminar streams collide. The use of a flowing liquid film is inexpensive and the interaction surface refreshes automatically, avoiding buildup of on-target debris. The composition of the liquid material and the relative angle of the film-generating nozzles was optimized for this application. Spectra measured in reflection from a water-based plasma mirror showed a blue shift but an optical reflectivity of up to 30%. The thickness of the film was found to be of the order of 2 ${\rm \mu}$m, and the stability of the reflected spot was ${\approx }1$ mrad. The reflected beam profile was highly distorted but stable. Further optimization of the nozzles to affect the fluid flow should enable significant improvements in control of the fluid films and increase in the reflectivity of these mirrors.

Mitophagy in Hypertension-Associated Premature Vascular Aging.

Hypertension has been described as a condition of premature vascular aging, relative to actual chronological age. In fact, many factors that contribute to the deterioration of vascular function as we age are accelerated and exacerbated in hypertension. Nonetheless, the precise mechanisms that underlie the aged phenotype of arteries from hypertensive patients and animals remain elusive. Classically, the aged phenotype is the buildup of cellular debris and dysfunctional organelles. One means by which this can occur is insufficient degradation and cellular recycling. Mitophagy is the selective catabolism of damaged mitochondria. Mitochondria are organelles that contribute importantly to the determination of cellular age via their production of reactive oxygen species (ROS; Harman’s free radical theory of aging). Therefore, the accumulation of dysfunctional and ROS-producing mitochondria could contribute to the acceleration of vascular age in hypertension. This review will address and critically evaluate the current literature on mitophagy in vascular physiology and hypertension.

Mitochondria and Aging-The Role of Exercise as a Countermeasure.

Mitochondria orchestrate the life and death of most eukaryotic cells by virtue of their ability to supply adenosine triphosphate from aerobic respiration for growth, development, and maintenance of the ‘physiologic reserve’. Although their double-membrane structure and primary role as ‘powerhouses of the cell’ have essentially remained the same for ~2 billion years, they have evolved to regulate other cell functions that contribute to the aging process, such as reactive oxygen species generation, inflammation, senescence, and apoptosis. Biological aging is characterized by buildup of intracellular debris (e.g., oxidative damage, protein aggregates, and lipofuscin), which fuels a ‘vicious cycle’ of cell/DNA danger response activation (CDR and DDR, respectively), chronic inflammation (‘inflammaging’), and progressive cell deterioration. Therapeutic options that coordinately mitigate age-related declines in mitochondria and organelles involved in quality control, repair, and recycling are therefore highly desirable. Rejuvenation by exercise is a non-pharmacological approach that targets all the major hallmarks of aging and extends both health- and lifespan in modern humans.

In situ solvent recovery by using hydrophobic/oleophilic filter during wet lipid extraction from microalgae

While lipid extraction from wet microalgae has attracted attention as an economical method for microalgal biofuel production, few studies have focused the actual separation of extract phase from the emulsified extraction mixture. Here, a novel approach which utilizes hydrophobic/oleophilic filter was developed for the efficient solvent recovery. The filter was surface-modified by coating a functional polymer via initiated vapor deposition for the selective solvent permeability. While acid-treated Chlorella sorokiniana HS1 and n-hexane was stirred for lipid extraction, tubular filter module was immersed into the mixture for separation. The mixture was kept stirred during the separation to inhibit the buildup of cell debris on the filter by inducing crossflow on the filter. Extract phase was separated directly from the raffinate phase with high separation efficiency (> 98.3%) while maintaining permeation flux. The place-, space- and energy-efficient strategy reported here could be a useful tool for the solvent extraction process.

Metallosis: A New Form of Autoimmune/Autoinflammatory Syndrome Induced by Adjuvants Syndrome (ASIA)?

Autoimmune/autoinflammatory syndrome induced by adjuvants (ASIA) is a new entity in which exposure to an adjuvant triggers an aberrant autoimmune response. Metallosis is a rare condition characterized by the deposition and build-up of metal debris in the soft tissues of the body associated with metal-on-metal (MOM) prosthetic devices. It can present with local/systemic symptoms and signs due to a chronic inflammatory host response. The authors present the case of a 51-year-old woman with a 6-month history of systemic complaints due to intoxication with metal ions from hip metallosis. This case highlights the importance of follow-up and continuous monitoring of patients with a hip prosthesis. As this is a rare condition, a patient presenting with unspecific symptoms such as ASIA syndrome induced by metallosis requires a high level of clinical suspicion as the removal of the adjuvant can resolve the condition.LEARNING POINTSAsia syndrome is a new entity in which exposure to an adjuvant triggers an aberrant autoimmune response.Metallosis is an uncommon condition with local and systemic presentation.A high level of suspicion and close monitoring is needed in patients with vague systemic complaints.

Oxide induced crack closure in the near threshold regime: The effect of oxide debris release

Within this work the influence of oxide particle transport during fatigue loading on the fatigue propagation rate was investigated in detail by means of load-shedding tests in the near threshold region (crack propagation rate between 0.1 and 10 nm per cycle). To this purpose, standard fatigue specimens (SENB - single edge notch bending) were machined. At selected specimens, a stretchable nitrile rubber patch was glued onto the sample surfaces in the ligament region. This patch was expected to prevent the emergence of iron oxide particles near the sample surface, and indeed subsequent fracture surface analysis showed obvious differences in the shape of the arising oxide debris layer. It is shown that the build-up of oxide debris on the fracture surface is higher in the specimen with the nitrile rubber patch applied. This leads to increased oxide induced crack closure and, in turn, to a higher fatigue crack growth threshold. In this context, also the influence of the specimen thickness on the fatigue crack growth threshold is examined. Finally, also the influence of the load ratio on the oxide debris layer is briefly discussed.

Brain region-specific enhancement of remyelination and prevention of demyelination by the CSF1R kinase inhibitor BLZ945

Multiple sclerosis (MS) is a chronic inflammatory disease affecting the central nervous system (CNS). While multiple effective immunomodulatory therapies for MS exist today, they lack the scope of promoting CNS repair, in particular remyelination. Microglia play a pivotal role in regulating myelination processes, and the colony-stimulating factor 1 (CSF-1) pathway is a key regulator for microglia differentiation and survival. Here, we investigated the effects of the CSF-1 receptor kinase inhibitor, BLZ945, on central myelination processes in the 5-week murine cuprizone model by non-invasive and longitudinal magnetic resonance imaging (MRI) and histology. Therapeutic 2-week BLZ945 treatment caused a brain region-specific enhancement of remyelination in the striatum/cortex, which was absent in the corpus callosum/external capsule. This beneficial effect correlated positively with microglia reduction, increased oligodendrocytes and astrogliosis. Prophylactic BLZ945 treatment prevented excessive demyelination in the corpus callosum by reducing microglia and increasing oligondendrocytes. In the external capsule oligodendrocytes were depleted but not microglia and a buildup of myelin debris and axonal damage was observed. A similar microglial dysfunction in the external capsule with an increase of myelin debris was obvious in triggering receptor expressed on myeloid cells 2 (TREM2) knock-out mice treated with cuprizone. Finally, therapeutic BLZ945 treatment did not change the disease course in experimental autoimmune encephalomyelitis mice, a peripherally driven neuroinflammation model. Taken together, our data suggest that a short-term therapeutic inhibition of the CSF-1 receptor pathway by BLZ945 in the murine cuprizone model enhances central remyelination by modulating neuroinflammation. Thus, microglia-modulating therapies could be considered clinically for promoting myelination in combination with standard-of-care treatments in MS patients.

High Intrinsic Aerobic Endurance Capacity Preserves Cardiomyocyte Quality Control, Mitochondrial Fitness and Lifespan

Growing evidence has established cardiorespiratory fitness (CRF) as a strong and reliable quantitative predictor of elderly mortality and cardiovascular events. To gain insight into potential mechanisms linking high CRF to increased healthspan and lifespan, we examined cardiomyocytes from rats selectively bred for low and high intrinsic aerobic capacity, the so-called low capacity runners (LCR) and high capacity runners (HCR). LCR vs HCR have been shown to differ in numerous ageing related diseases (including the metabolic syndrome and cardiovascular complications) and longevity. We hypothesized that differences in mitochondrial function, homeostatic performance and stress-resistance (i.e., fitness) underlie the ageing- and CRF-linked risks of developing chronic disease and multimorbidity. We demonstrated that autophagy/mitophagy is significantly diminished in old compared to younger rats, and is significantly lower in LCR vs HCR compared across all age groups (14%, 26% and 30% lower in LCR vs HCR at 7, 17 and 24-month-old, respectively). Accumulation of lipofuscin (the progressive buildup of intralysosomal debris) gradually increased with age (by 5-fold at 24 vs 7 months) reaching significantly higher levels in aged LCR vs HCR, in parallel with the decline in autophagic turnover, suggesting significant alteration in the balance between damage and repair. Indeed, impaired autophagy/mitophagy may perturb mitochondrial quality control as manifested by a pronounced age-dependent decrease in the ROS-threshold for opening of the permeability transition pore (50% decrease in 24-month vs 7-month-old; LCR>HCR) and hence a deterioration in fitness of the organelle, eventually, leading to a decline in cell function. In summary, observed changes in mitochondrial repair, turnover and fitness may contribute to a decreased functionality and increased vulnerability to injury of the aged heart that is more pronounced in LCR vs HCR, and may underlie differences in healthspan and lifespan.

Holding Water: Congenital Anomalies of the Kidney and Urinary Tract, CKD, and the Ongoing Role of Excellence in Plumbing.

Congenital anomalies of the kidneys and urinary tracts can result in diminished natal kidney function, possibly through common embryologic pathway disruption or as a result of development taking place in the face of disordered 'post-renal' drainage. Impaired conduit and reservoir function present potential for an ongoing assault leading to further deterioration and progression of chronic kidney disease, a risk that extends to adults with these conditions, even after "correction". The drainage and storage aspects of the urinary system that can impact kidney function are reviewed with attention to correctable or manageable problems including: Bladder dysfunction wherein the low pressure storage of urine is compromised requiring the kidney to work against a pressure gradient, the classic post renal failure problem. The kidney in the aftermath of obstruction which may have lost concentrating capacity leading to a tendency to dehydration ('pre-renal' failure) and through polyuria which exacerbatesbladder pressure problems. Further there is an added challenge in evaluation for ongoing or reemergent obstruction in a significantly dilated system where the capacious system leads to slow turnover of urine often requiring a ureteral stent or nephrostomy to clearly establish clinical significance of delayed drainage. Stasis where slow urine flow leads to buildup of debris (stone) or potentiates infection. Vessicoureteral reflux which allows for introduction of lower urinary tract bacteria to the kidney and can lead to pyelonephritis. Conditions which combine problems such as posterior urethral valves where the bladder outlet obstruction compromises kidney function potentially impairing concentrating ability, creates bladder compromise often reducing emptying efficiency or elevating bladder storage pressures, as well as dilating the system potentially promoting stasis. Cognizance of the potential for plumbing problems to further kidney deterioration as patients with congenital urinary tract anomalies, even after they have been repaired is incumbent on those caring for these patients as they age. Thoughtful evaluation of those patients in whom kidney compromise maybe aggravated by drainage and storage disorder will optimize native renal function.

Difference in the indices of adipose tissue and peripheral blood cells of individuals with overweight

Background: Overweight is one of the predisposing risk factors for the development of different diseases, pathogenesis of which is grounded on the various types of disturbances of the adipose tissue structure, impeding both local and systemic metabolism. Recent experimental and clinical studies have revealed a new phenomenon: overweight leads to inflammation of adipose tissue and dynamically acts on the peripheral blood monocytes. In this correlation, the utmost importance is given to macrophages of the white adipose tissue (WAT) and monocytes, which account for not only the necrosis of adipocytes and utilization of the cellular debris, but also to the formation and persistence of the chronic inflammation sites. Aim of the study: To identify the dynamic morphologic changes in adipose tissue in individuals with overweight and with different degrees of obesity, taking into account the ability of leptin to activate PMNs; find out the correlation between the altered level of inflammation, plasma levels of leptin and changes of cells in peripheral blood, monocytes/tissue macrophages and PMNs; perform the quantitative assessment of the data. Methods: puncture biopsy samples from the gluteal area white adipose tissue and 2 ml. of venous blood samples were collected from male (n=14) and female patients (n=11) with age ranging in 41.5±12.3 years (mean ± SD), receiving treatment for overweight and increased body mass. The body mass index (BMI) was calculated by Quetelet index: BMI = body weight (kg) / height 2 (m). The patients were classified depending on BMI according to the degree of obesity (WHO, 1997). The leptin was measured in the blood serum by immunoenzyme method using the reagents kit (“Leptin (Sandwich) ELISA”, DRG Instruments GmbH, Germany). Histological and Electron microscopic methods were used. Results and conclusion . Based on the given data, statistically significant differences were obtained in all studied parameters between group I (normal weight + overweight) and group II (I, II and III degree obesity) (t-criterion of Student and U-criterion of Mann-Whitney) (Table 2a, 2b, 3). The state of monocytes/ macrophages and peripheral blood cells reflects not so significantly obvious changes on the body weight, increased production and utilization of leptin activates the recruitment of macrophages from peripheral blood, simultaneously promoting their phagocytic function, which eventually leads to lipophagocytosis, necrosis and build-up of cellular debris with repeated activation of macrophages. Consequently, the interrelation between increased production of leptin, breakdown of adipocytes from WAT and characteristic reaction of monocytes and macrophages on increased body weight represents the cause for persisting sites of necrosis in adipose tissue and formation of chronic inflammatory response, supporting to remodeling of adipocytes and progression of derangements in fat metabolism from increased body weight to different degrees of obesity, having at the same time the important diagnostic and prognostic potential.

INFLUENCE OF TIRE DEBRIS ON TIRE PERFORMANCE

ABSTRACT A large number of wear debris particles can be found on the tread surface at any time during normal tire operation. In highly accelerated lab tests, it has been shown that wet friction is decreased by the buildup of debris, and the level of friction can be increased when debris is effectively removed from the interface. In wet traction tests on the road, it has been shown that when tires are cleaned from debris, a higher braking force coefficient in straight-ahead braking on wet asphalt is achieved, compared with the same tires that were not cleaned from debris prior to tests. This was observed for both carbon black– and silica-filled tread compounds. It has also been shown that laboratory wear rate can be increased by effective removal of debris. We propose that the presence of tread-wear debris on the tread surface in dry operating conditions would be beneficial for abrasion resistance and, on the other hand, debris removal from the tread surface in wet operating conditions would be beneficial for wet skid resistance.