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Background. MicroRNAs are endogenous, small noncoding RNA molecules that play a pivotal role in the regulation of gene expression. MicroRNAs are involved in many biological processes such as proliferation, cell differentiation, neovascularization, and apoptosis. Studies on microRNA expression may contribute to a better understanding of the pathomechanism of chronic inflammatory demyelinating polyneuropathy (CIDP) and consequently enable the development of new therapeutic measures using antisense miRNAs (antagomirs). In this study, we evaluated the level of miR-31-5p in the serum of patients with CIDP and its correlation with the miR-31-5p level and clinical presentation and electrophysiological and biochemical parameters. Methods. The study group consisted of 48 patients, mean age 61.60 ± 11.76 , who fulfilled the diagnostic criteria of a typical variant of CIDP. The expression of miR-31-5p in patient serum probes was investigated by droplet digital PCR. The results were correlated with neurophysiological findings and the patient’s clinical and biochemical parameters. Results. The mean copy number of miRNA-31 in 100 μl serum was 1288.64 ± 2001.02 in the CIDP group of patients, while in the control group, it was 3743.09 ± 4026.90 . There was a significant positive correlation (0.426) between IgIV treatment duration and miR-31-5p expression. Patients without IgIV treatment showed significantly lower levels of miR-31 compared to the treated group ( 259.44 ± 304.02 vs. 1559.48 ± 2168.45 ; p = 0.002 ). The group of patients with body weight > 80 kg showed statistically significantly lower levels of miRNA-31-5p than the patients with lower body weight ( 934.37 ± 1739.66 vs. 1784.62 ± 2271.62 , respectively; p = 0.014 ). Similarly, the patients with elevated cerebrospinal fluid (CSF) protein levels had significantly higher miRNA-31-5p expression than those with normal protein levels ( 1393.93 ± 1932.27 vs. 987.38 ± 2364.10 , respectively; p = 0.044 ). Conclusion. The results may support the hypothesis that miR-31-5p is strongly involved in the autoimmune process in CIDP. The positive correlation between higher miR-31-5p levels and duration of IVIg treatment may be an additional factor explaining the efficacy of prolonged IVIg therapy in CIDP.

Background Chronic exposure to heavy metals affects various organs, among them the brain and peripheral nerves. Polyneuropathy is mainly length-dependent with predominantly sensory symptoms. There have been few studies on small fiber neuropathy due to heavy metal intoxication. Methods We investigated 41 metal industry workers, mean age 51.3 ± 10.5 years, with at least 5 years’ professional exposure to heavy metals, and 36 age- and sex-matched healthy controls. We performed neurological examinations, and assessed blood levels of cadmium, lead, and zinc protoporphyrin, urine levels of arsenic, standard, sensory and motor electrophysiological tests in the ulnar and peroneal nerves, sympathetic skin responses from the palm and foot, and quantitative sensation testing from dermatomes C8 and S1. Discussion The results of standard conduction tests of all nerves significantly differed between groups. The latency of sympathetic skin responses achieved from the foot was also statistically significantly prolonged in the study group. Significant differences were seen in both C8 and S1 regions for temperature and pain thresholds, and for vibratory threshold only in the S1 region, while the dispersions of low and high temperatures were important exclusively in the C8 region. Conclusions We can conclude that co-exposure to many heavy metals results in explicit impairment of peripheral nerves. The lesion is more pronounced within small fibers and is predominantly connected with greater impairment of temperature-dependent pain thresholds. The evaluation of small fiber function should be considered in the early diagnosis of toxic polyneuropathy or in low-dose exposure to heavy metals.

Introduction Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an autoimmune disease of the peripheral nervous system, sometimes including the central nervous system. The aim of the study was the assessment of the prevalence of central sensory impairment and its reliance on peripheral nerve damage in patients with CIDP. Material and methods Multimodal (visual—VEP, brainstem auditory—BAEP, somatosensory—SEP) evoked potentials (EPs) were studied in 24 patients diagnosed with CIDP. The results were compared with neurographic parameters of sensory responses. The control group consisted of 35 healthy volunteers selected with respect to age and sex. Results Mean latency of most components of EP were considerably prolonged in patients compared with the control group. There were no correlations between the P100 VEP latency and the peripheral sensory parameters. Statistically significant negative correlations were obtained between BAEP and SEP responses and the amplitude and sensory conduction velocity of peripheral nerves. The inter-latencies were also longer. Conclusions The authors indicated to the possibility of central sensory involvement in patients with CIDP, especially based on the prolonged inter-latency of BAEPs with simultaneously confirmed root affection. The severity of central damage correlates with the degree of peripheral nerve impairment.

The results of grain size distribution of loess units are suitable for the study of past climate change. There are many methods for the analysis of the grain size, but clustering methods have not been used before. In this article, a new approach in the sediment research, the k-median method was used. This method separates the grain size classes of the youngest loess units of three loess-soil profiles in Poland: Biały Kościół, Złota and Tyszowce. In the analysis, only the content for the loess silt fraction (range from 4 to 63 µm) was used. This allowed eliminating the admixtures of sandy and clay fraction, considered as secondary material. For the purposes of this analysis, silt fractions were divided into smaller units using a 1/4 phi interval, resulting in 16 new subfractions. The grain size data from three profiles were combined into one data set. As a result, four classes with a similar internal of grain structure were obtained. The separated classes showed the sedimentological variability of the sediment well. It has been shown that the k-median method can be used to classify loess in a fast and objective way.

The aim of this study is geomorphometric relief classification of a temperate latitude upland area in Central Europe. The Silesian Upland represents diversified structural relief which contains a fan-shaped configuration of long thresholds and wide erosion depressions. A 20 m × 20 m digital elevation model (DEM) provided input data for the analysis. The k-median method was applied to examine morphometric variables of the relief. The aim of these activities was to identify clusters with objects of similar mathematical characteristics. These clusters were the basis of landform classification. Smaller numbers of clusters 4 transparently show hypsometric relationships. Key elements of the morphology of the area were clearly visible. The division into 6 clusters gives the best results—a detailed but clear image of the morphological diversity by distinguishing characteristic landform elements. The results for 8 clusters show significant background noise and are ambiguous, which makes them difficult to identify. Our research has confirmed that the k-median method is a useful tool for landform classifications. We determined optimal parameters of this method (filtering window size, DEM resolution, number of clusters, aspect influence).

Introduction: The aim of this study is a comprehensive analysis of the parameters of exogenous evoked potentials (visual, brainstem auditory, and somatosensory) in patients with myasthenia gravis (MG), a prototype of both neuromuscular junction disease and autoimmune disease. The study also seeks to isolate electrophysiological changes that may indicate disorders within the central and/or peripheral nervous system. Methods: A total of forty-two consecutive patients with myasthenia gravis (24 women, 18 men) were included in the study. All of the patients underwent EP examination. MR images were also analyzed. Results: In the group of MG patients, the latency of P100 (113.9 ± 13.9, p &lt, 0.0001) VEP, wave III (3.92 ± 0.29, p = 0.015), wave V (5.93 ± 0.32, &lt, 0.0001), interlatency III–V (2.00 ± 0.12, 0.0001), interlatency I–V (4.20 ± 0.28, 0.001) BAEP, and all components of SEP (N9, P10, N13, P16, N20, P22) were significantly longer. Mean wave I and V amplitude BAEP were relatively lower. Conclusions: The results of the study suggest the presence of disturbances in the bioelectric activities of the central and peripheral nervous system in MG patients.

The goal of this study was to analyse, in relation to electrophysiological results, the distribution of lymphocyte subpopulations and the level of cytokines in patients with the typical form of chronic demyelinating inflammatory polyneuropathy (CIDP) before immunoglobulin treatment. The study group consisted of 60 patients (52 men, eight women), with a mean age 64.8 ± 11.2, who fulfilled the diagnostic criteria for the typical variant of CIDP, with (23 patients) and without (37 patients) diabetes mellitus. We analysed the results of the neurophysiological tests, and correlated them with the leukocyte subpopulations, and cytokine levels. In CIDP patients, IL-6, IL-2, IL-4 and TNF-α levels were significantly increased compared to the control group. Fifty patients had decreased levels of T CD8+ lymphocytes, and 51 patients had increased levels of CD4+ lymphocytes. An increased CD4+/CD8+ ratio was also found. Negative correlations were observed mainly between compound muscle action potential (CMAP) amplitudes and cytokine levels. The study enabled the conclusion that electrophysiological parameters in CIDP patients are closely related to the autoimmune process, but without any clear differences between patients with and without diabetes mellitus. Correlations found in the study indicated that axonal degeneration might be independent of the demyelinating process and might be caused by direct inflammatory infiltration.

W trackie badań identyfikacyjnych pisma ręcznego z wykorzystaniem metody graficzno-porównawczej głównym przedmiotem aktywności badaczajest nawyk pisarski. Jest to zespół cech pisma stabilnych, niezależnych od zmieniających się warunków w grafizmie konkretnego człowieka. Jako funkcjonalne w badaniach identyfikacyjnych pisma ręcznego wykonywanych wskazaną metodą należy uznać pismo, w którym możliwe jest ustalenie i przebadanie cech nawykowych, tj. ustabilizowanych i zindywidualizowanych ruchów aparatu piszącego, którymi kreślone są poszczególne detale znaków graficznych oraz ich zespoły. W badaniach identyfikacyjnych pisma ręcznego nie wystarczy ustalenie zgodności samych konstrukcji znaków graficznych oraz ichzespołów w obrębie materiału dowodowego, oraz materiału porównawczego, a ustalenie jakie ruchy aparatu piszącego były ich siłą sprawczą. W kontekściepoczynionych uwag, ustalenie przez badacza zindywidualizowanych nawyków pisarskich jest najistotniejszym elementem badań identyfikacyjnych pismaoraz determinuje proces badawczy w ramach metody graficzno-porównawczej. Jeśli w piśmie nie uda się ustalić i przebadać nawyku pisarskiego, zdaniemautora dany rękopis nie może być przedmiotem pozytywnej lub negatywnej identyfikacji w ramach metody graficzo-porównawczej badania pisma.

INTRODUCTION Median and ulnar nerves are used in comparative electrophysiological studies. We analyzed the conduction values in these hand nerves in healthy volunteers to find any physiological differences between them. METHODS We performed standard conduction studies and conduction velocity distribution (CVD) tests with estimation of 3 quartiles in 31 healthy right-handed volunteers (17 women, 14 men) with a mean age of 44.8 ± 15.5 years. RESULTS The conduction velocities in all quartiles of CVD tests were statistically faster in the ulnar nerve (P

BACKGROUND Cerebrovascular disease is an important cause of epilepsy. The incidence may significantly vary (from 2.3% to 43%). Post-stroke seizures occur within 2 weeks of stroke onset (as early-onset seizures) or 2 weeks after a stroke (as late-onset seizures). OBJECTIVES To retrospectively evaluate and differentiate predictive factors for post-stroke seizures. MATERIAL AND METHODS We retrospectively analyzed the medical histories of 164 adult patients diagnosed with post-stroke seizures but no epilepsy recognized prior to the stroke who were hospitalized at the Neurology Clinic of Wroclaw Medical University between 2012 and 2018. The seizures were classified according to the criteria of the International League Against Epilepsy (ILAE) from 2017. The relevant demographic data, type of stroke (ischemic/hemorrhagic), time of occurrence of seizures in relation to the type of stroke, score on the modified Rankin Scale, presence of cardiovascular risk factors, electroencephalography (EEG) recording, and antiepileptic treatment (AED) were collected. In the case of ischemic stroke (IS), the size of the stroke lesion was rated on the ASPECTS scale. RESULTS The study involved 164 patients (average age = 68.83 years), including 86 men (average age = 66.2 years). In 20 out of 164 patients, the seizures were associated with hemorrhagic stroke (HS); in 144 out of 164 patients, the post-stroke epilepsy was associated with IS. Generalized tonic-clonic seizures occurred in 101 out of 164 patients, focal aware seizures occurred in 19 out of 164 patients and focal impaired-awareness seizures occurred in 44 out of 164 patients. CONCLUSIONS Our study has confirmed that generalized seizures occur mostly after an IS and are late complications of it. Early-onset seizures occur mostly after HS associated with severe disability. Seizures are more likely to happen due to the cortical location of the stroke. There is a shift from generalized to focal seizures with an increase in the extent of IS as evaluated using the ASPECTS scale.

In this paper, we quantify the changes in precipitation distribution in south-western Poland between the periods 1891–1930 and 1981–2010. The average monthly precipitation totals available for 368 and 245 stations, respectively, are spatially interpolated and processed to calculate maps of differences and pluvial continentality indices for both periods. The maps are analysed against changes in atmospheric circulation and take into account the potential role of the mountain barrier of the Sudetes. The main findings are (1) winter totals generally increased in conjunction with a higher frequency of zonal circulation; it is more pronounced in the upper parts of the Sudetes due to orographic effects; (2) a decreased frequency of zonal circulation together with an increased frequency of southern flows has likely led to the reduction of precipitation in spring and autumn. These changes have led to a significant modification of the region’s pluvial regime, mostly by decreasing continentality features (especially in the Sudetes and the western lowlands). In addition, the strong sheltering influence of the mountain barrier is observed, driving the preservation or even the enhancement of the continental pluvial characteristics in the north-eastern to eastern foregrounds of the Sudetes. This leads to the conclusion that in areas where long-term observed trends or future projections of precipitation are ambiguous, there may occur significant modifications in regional characteristics, especially as a result of changes in atmospheric circulation modified by local orography.

Visual evoked potentials (VEP) are changes in potentials that arise in the central nervous system. In the interpretation of the VEP test results, it is assumed that the elongation of the latency time is caused by the demyelination of the nerve fibers, and the axon damage is responsible for the decrease in the amplitude. The observed VEP deviations are not specific for specific diseases, but indicate disturbances in visual conductivity. VEP may play a diagnostic role in the early detection of visual involvement. The aim of the study was the functioning of visual pathway assessment on the basis of visual evoked potentials (VEP) examination, in patients with primary Sjögren’s Syndrome (pSS), without focal symptoms of central nervous system disorder. The effect of disease activity, as assessed by clinical parameters and antibody levels (anti-Ro52, SSA, and SSB), on the central nervous system was also evaluated. Thirty-two consecutive patient with pSS (31 females, 1 male) were included in the study. VEP was performed at baseline, and after 6 (T6) years. Their results were compared longitudinally between the baseline and T6, depending on the duration of the disease and treatment. The immunological activity of pSS was also analyzed. The group of patients showed a significant prolongation of the P100 implicit time (105.5 ± 5.1 vs. 100.6 ± 3.9, p = 0.000) and a significant higher the P100-N145 amplitude (12.3 ± 4.1 vs. 9.4 ± 3.0, p = 0.000). Abnormalities in electrophysiological parameters of VEP at baseline correlated with presentation of anti-Ro52 antibodies and aching joints. At baseline, the P100 implicit time was shorter for the patients with pSS than for those at T6 (105.50 ± 5.1 vs. 109.37 ± 5.67, p = 0.002). pSS patients without CNS involvement presented with dysfunction of visual pathway, as revealed by VEP abnormalities. Relationships were found between VEP parameters and with present of anti-Ro52 antibodies and aching joints. VEP may be a useful method for assessment and monitoring of subclinical visual deficit in the course of pSS.

A new method, named as the nested k-means, for detecting a person captured in aerial images acquired by an unmanned aerial vehicle (UAV), is presented. The nested k-means method is used in a newly built system that supports search and rescue (SAR) activities through processing of aerial photographs taken in visible light spectra (red-green-blue channels, RGB). First, the k-means classification is utilized to identify clusters of colors in a three-dimensional space (RGB). Second, the k-means method is used to verify if the automatically selected class of colors is concurrently spatially clustered in a two-dimensional space (easting-northing, EN), and has human-size area. The UAV images were acquired during the field campaign carried out in the Izerskie Mountains (SW Poland). The experiment aimed to observe several persons using an RGB camera, in spring and winter, during various periods of day, in uncovered terrain and sparse forest. It was found that the nested k-means method has a considerable potential for detecting a person lost in the wilderness and allows to reduce area to be searched to 4.4 and 7.3% in spring and winter, respectively. In winter, land cover influences the performance of the nested k-means method, with better skills in sparse forest than in the uncovered terrain. In spring, such a relationship does not hold. The nested k-means method may provide the SAR teams with a tool for near real-time detection of a person and, as a consequence, to reduce search area to approximately 0.5–7.3% of total terrain to be visited, depending on season and land cover.

Background. Transient global amnesia (TGA) is a rare, benign condition characterised by a sudden deficit of anterograde and retrograde memory that usually lasts for a few hours and is not accompanied by other focal neurological symptoms or signs. Its aetiology is still unclear. Various events or activities may trigger TGA. Evidence of seasonal variations in the appearance of TGA is inconsistent. Methods. We retrospectively analysed the medical history of 114 adult patients with diagnosed TGA, hospitalised at two neurology departments in Wroclaw from 2008 to 2014. We reviewed risk factors, trigger points, and occurrence in each month of the year in our patient population. Results. Over this seven-year period, 114 patients were diagnosed with TGA. The annual occurrence ranged from 13 to 22 hospitalisations. The mean age of the patients was 64 years. There were 36 TGA events in men and 78 in women. TGA occurred most frequently in spring (36%) and summer (30%), with the incidence peaking during March. Conclusions. Our findings suggest that there is a relationship between the season of the year and the probability of TGA.

The Sahara Desert episodically became a space available for hominins in the Pleistocene. Mostly, desert conditions prevailed during the interpluvial periods, which were only periodically interrupted by enhanced precipitation during pluvial or interglacial periods. Responding to Quaternary climatic changes, hominin dispersal was channeled through vegetated corridors. This manuscript introduces a recently discovered group of Acheulean and Middle Stone Age sites far from the Nile Valley in the Eastern Desert (Sudan), referred to as Eastern Desert Atbara River (EDAR). The ∼5 m stratigraphy of the area is divided into three units (Units I-III) bounded by erosion surfaces. Each contains archaeological horizons. The EDAR area has rich surface sites with Acheulean horizons under the surface, singular finds of hand-axes within stratigraphic context in exposures, and large Acheulean sites partly exposed and destroyed by the gold mining activity. Optically stimulated luminescence (OSL) dating of Acheulean and MSA horizons from the EDAR 135 site indicates that the sedimentary deposits with stone artifacts were formed during the Middle Pleistocene between Marine Isotope Stages (MIS) 7 (pluvial) and 6 (interpluvial). Based on the OSL dating from the top of Unit IB, Acheulean artifact-bearing sedimentary deposits from overlying Unit IIA are younger than ca. 231 ka. Unit IA is the oldest Acheulean horizon in the EDAR area, not yet dated but definitively older than ca. 231 ka. An MSA horizon found in fluvial sediment was dated to be between 156 and 181 ka by OSL. The EDAR Pleistocene archaeological sites provide evidence for the presence of additional corridor(s) across Nubia, which connects the early hominin dispersals from the Nile and Atbara River systems to the Red Sea coast.

Background Primary Sjogren’s syndrom (pSS) is a chronic autoimmune disease, which, in addition to impaired function of exocrine glands, can affect other organs including nervous system. Objectives The aim of the study was to establish whether in patients with pSS without central nervous system (CNS) involvement, the function of the central portion of the sensory pathway can be challenged. Methods In 33 patients diagnosed with pSS without clinical features of CNS damage and normal head CT scan, somatosensory evoked potentials (SEP) were studied. The results were compared to other clinical parameters of the disease, particularly to immunological status. The control group consisted of 20 healthy volunteers selected with respect to age and sex. Results Mean latency of all components of SEP were considerably prolonged in patients compared to the control group. Mean interpeak latency N20-N13 (duration of central conduction TT) did not differ significantly between the groups. However, in the study group, mean amplitude of N20P22 and N13P16 was significantly higher compared to healthy individuals. In patients with PSS, significant differences in SEP parameters depending on duration of the disease, duration of arthralgia and presence of SSA and SSB antibodies were noted. No significant differences in mean SEP parameters were observed with respect to skin lesions, xerophthalmia, current joint pain and swelling, focus score, levels of C3 and C4 complement components, ESR, CRP and presence of Ro52 antibodies. Conclusions The authors confirmed central nervous system involvement often observed in patients with pSS. They also showed dysfunction of the central sensory neuron as a difference in amplitude of cortical response, which indicates subclinical damage to the CNS. Disclosure of Interest None declared

When users read a topographic map, they have to decode the represented information. This decoding passes through various processes in order to perceive, interpret, and understand the reported information. This set of processes is intrinsically a question that is influenced by culture. In particular, when one thinks of maps distributed across the internet or representations of audiences from different origins, the chance of efficient communication is reduced or at least influenced. Therefore, there should be some degree of common visual communication, which the symbology of maps can be applied in order to assure the adequate communication of phenomenon being represented on it. In this context, the present work aims at testing which evaluation factors influence the reading of maps, the understanding of space and reasoning of the map user, in particular national topographic maps. The assessment was through internet considering official map representation from Brazil and Poland and questionnaires. The results shown that conventional topographic maps on the same scale are not capable of producing the correct interpretation of the user from another culture. This means that formal training has a direct influence on the quality of the interpretation and spatial reasoning. Those results indicate that high levels of formal training positively influence the reading and interpretation results of the map and that there is no evidence that the specialists with the symbology of their own country have significantly positive results, when compared to those used maps with systematic mapping from another country.

The aim of the article is an analysis of tourist traffic in the Aconcagua massif, one of the most popular peaks of the Seven Summits. On the basis of statistical data, the tourist traffic was analysed in a temporal and spatial perspective. The applied data made it possible to capture the dynamics of visits in the period 2000/2001 – 2012/2013 and with a breakdown into months, which helped analyse the tourist traffic in this area. In each of the analysed periods, January dominates. Data concerning the origin of tourists according to countries and continents, their age, gender and type of mountaineering activity were also taken into account. Most tourists came from Argentina, the USA and Germany. These are people of age groups 21–30 (33%) and 31–40 (31%). Men account for over 75% of visitors. The favourite mountaineering activity is climbing (about 60%). Aconcagua has invariably been a very popular peak among tourists and climbers. It is a place for training and acclimatisation for alpinists, participating in Himalayan expeditions and climbers collecting peaks of the Seven Summits.

Endogenous cognitive event-related potentials (CERPs) reflect higher-level processing of sensory information and can be used to evaluate cognitive functions. The aim of this paper was to determine whether there are any abnormalities in the electrophysiological parameters of CERPs in patients with primary Sjögren's syndrome (pSS) but without symptoms of central nervous system (CNS) involvement or mental disorder. The analysis of CERP parameters was then correlated with the clinical status of the patients and with some of the immunological parameters in the patient group.Thirty consecutive patients with pSS (29 females, one male) were included in the study. All the patients underwent CERP examination.There was a significant prolongation of the latency of P300 and N200 potentials in patients with pSS. Abnormalities in electrophysiological parameters of CERPs correlated with the duration of the disease, salivary gland abnormalities, and elevated erythrocyte sedimentation rate (ESR) values. Patients with coexisting chronic fatigue syndrome (CFS) had larger P300 amplitudes. There were no statistically significant changes in the electrophysiological parameters of CERPs in patients with pSS dependent on the presence of peripheral nervous system (PNS) lesions, skin changes, arthritis, abnormalities in white blood cells and the immune system or the levels of blood lipids.The results of the study suggest the presence of a minor cognitive dysfunction in patients with pSS without symptoms of CNS involvement or mental disorder. Cognitive dysfunction correlated with the disease duration time and the severity of inflammatory changes (salivary gland abnormalities and inflammatory markers in the blood). Further and larger longitudinal studies are necessary for confirmation of this correlation.

The main purpose of the study is to compare the results of automatic classification of landforms performed as unsupervised classification and manual (expert) morphographic landform classification derived from field mapping and recognition of long-term trends in landform evolution. Two test areas in the Sudetes Mountains (SW Poland) were selected, each representing a different type of relief. The Jelenia Gora Basin is an example of denudational hilly granite topography, with inselbergs, other residual hills, and basins, whereas the northern part of the Bystrzyckie Mountains is a faulted plateau underlain by sedimentary and metamorphic rocks. The setup of the classification involved a DEM derived from digitalization of 1:25,000 maps, a filter mask of 20 × 20 pixels (500 × 500 m), k -median cluster analysis, and consideration of four dimensions (relative height, slope, combined curvature, and aspect). We used a statistical criterion to decide the level of classification, i.e. the number of homogeneous groups returned. Output maps show the results of classification into five (Jelenia Gora Basin) or six groups (Bystrzyckie Mountains), later confronted with nine-group classification. In both areas automatic classification for k = 5 ÷ 6 performed well and the principal features of relief are well captured, despite very different landform patterns and long-term geomorphic histories. Slope and curvature are the main variables to differentiate individual terrain units (landforms), with an additional role of aspect in the faulted and tilted plateau. For k > 6 aspect becomes the main variable in the hilly relief and the pattern of terrain units becomes more fragmented, adversely impacting on the clarity of interpretation, while surfaces in the faulted plateau setting are further subdivided according to slope and curvature. The match between ‘expert’ maps and the results of automatic classification varies, depending on the landforms considered. While certain landforms are clearly associated with one particular group yielded by automatic classification, others fall into a number of groups and do not have distinctive signatures, despite different origins.

Background The central nervous system in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is involved in about 5% of patients. The aim of the study was the assessment of the prevalence of central sensory impairment, and its reliance on peripheral nerve damage in patients with CIDP. Materials and methods The study group consisted of 24 patients with mean age of 60.7, who fulfilled the diagnostic criteria of typical form of CIDP at the time of multimodal (visual - VEP, brainstem auditory - BAEP, somatosensory SEP) evoked potentials (EPs) study. Each patient underwent a neurological examination, as well as a CT/MRI scan of the head. The evoked potentials was conducted according to the International Federation of Clinical Neurophysiology (IFCN) guidelines. Results Mean latency of most components of EP were considerably prolonged in patients compared to the control group. Negative correlations of SNAP amplitudes and sensory conduction velocities in peripheral nerves were obtained for I-V and III-V inter-latencies BAEP, for N20, P16, P22 SEP and the central conduction time TT for all sensory fibers of the left upper limb nerves. Conclusions Correlations of SNAP and EP parameters indicate subclinical damage to the central sensory pathways. The CIDP pathomechanism is still unclear and needs further research.

Consider a family of elliptic curves E q , m : y 2 = x ( x − 2 m ) ( x + q − 2 m ) , where q is an odd prime satisfying q − 2 m > 0 . In a case q − 2 m is a prime, we give fairly complete formula for the rank, and describe an elementary method to search for non-trivial points. In general case we can prove that either the rank or 2-part of the Tate–Shafarevich group can be arbitrarily large. We also prove (under reasonable assumptions) that for any partition k = l + n into non-negative integers there are pairwise nonisogeneous elliptic curves E 1 , … , E k among E q , m 's such that for a positive proportion of prime quadratic twists by p we have: rank E 1 ( p ) = ⋯ = rank E l ( p ) = 0 and rank E l + 1 ( p ) = ⋯ = rank E k ( p ) = 1 . We prove explicit estimates for the canonical height on (quadratic twists of) E q , m (in a case q − 2 m is a prime) and include a list of values of the analytic order of .

Fix an elliptic curve y2 = x3 + Ax + B, satisfying A, B ∈ , A ≥ |B| > 0. We prove that the -torsion subgroup is one of (0), /3, /9. Related numerical calculations are discussed.

Morphometric analyses performed on various areas and various methods are still very popular nowadays. There are both raster data and vector data analysed in this scope. In this article, there is a comparison described between two analyses of the same area. The input data was a 10 m × 10 m raster DEM representing SW part of Spitsbergen with actual size 15 km × 18 km. The data was characterized by 5 attributes: relative height, slope, aspect, and also plan and profile curvature. The first analysis was done on the full input data. For the other one, the input data was limited to the mainland only (excluding waters and subarea with glacier itself). In both classifications k-median method with Manhattan metric was used. The results were compared using statistical methods and visual evaluation. More detailed analyses were performed for two selected classifications. Finally, it is remarkable that suggested limitation of analyzed area improved homogeneity of result classes.

The paper presents the results of preliminary research aimed at the diagnosis of the level of competency of students beginning their academic education in the fields of social sciences and the humanities, concerning their preparation for activity in the digital learning environment. The present study took into account the skills of being active in the digital environment in terms of the educational process. For the purposes of the present study, the main areas of competency in the field of ICT were specified, in which the respondents rated the level of their skills. The distinguished areas of competency are the basis for proper functioning in the world of the new media and the process of lifelong learning. Information and digital competencies, analysed in the paper, are considered to be the elements of information culture understood as a sphere of human activity shaped by information awareness, values in support of the need for information literacy and attitudes that cause behaviour characteristic of information mature users, resulting from the interaction between the above-mentioned components of culture.

Image plays an increasingly important role in the modern educational process. The development of information and communication technologies has made it possible to easily create, modify and publish the visual and multimedia materials. The internet is becoming a learning environment in which educational content can be presented in a different form consisting of the text, hypertext, digital images, multimedia, hypermedia, etc. In this paper the authors discuss the possibility of using an image as a media content in the educational process in the context of the design space for blended learning. They present the results of research on the level of use of visual materials in academic practice and evaluation of their effectiveness by students. They point to the role of visual skills and visual knowledge as components of cultural capital of modern man, also pay attention to the learning potential inherent in the image as an independent unit of knowledge.

Fix and elliptic curve y2 = x3 + Ax + B, satisfying A, B ∈ ℤ A ≥ |B| > 0. We prove that the associated quadratic family contains infinitely many elliptic curves with trivial Mordell-Weil group.