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Wireless Local Area Networks (WLANs) have revolutionized modern communication by providing a user-friendly and cost-efficient solution for Internet access and network resources. However, the increasing popularity of WLANs has also led to a rise in security threats, including jamming, flooding attacks, unfair radio channel access, user disconnection from access points, and injection attacks, among others. In this paper, we propose a machine learning algorithm to detect Layer 2 threats in WLANs through network traffic analysis. Our approach uses a deep neural network to identify malicious activity patterns. We detail the dataset used, including data preparation steps, such as preprocessing and division. We demonstrate the effectiveness of our solution through series of experiments and show that it outperforms other methods in terms of precision. The proposed algorithm can be successfully applied in Wireless Intrusion Detection Systems (WIDS) to enhance the security of WLANs and protect against potential attacks.

The aim of this study was to compare the effectiveness of two diagnostic methods: ultrasonic gingival thickness measurement (UGTM) and cone-beam computed tomography, intraoral scanning by computer-aided design technology with prosthetic-driven implant planning software (CBCT/CAD/PDIP) in determining the gingival phenotype (GP). Thirty periodontally healthy patients were examined. The ultrasonic device Pirop G ® with a frequency of 20 MHz and CBCT/CAD/PDIP were used to measure gingival thickness at upper canines and incisors in three points localized midbuccally, namely free gingival thickness (FGT), supracrestal (SGT) and crestal (CGT). Probing depth (PD), clinical attachment level (CAL) and width of keratinized tissue (WKT) were measured using periodontal probe. Intra-examiner and inter-examiner agreement and agreement between methods were evaluated using Bland-Altman analyses. Comparing both methods in the determination of SGT (bias = 0.17 mm, SD = 0.25 mm, p < 0.000) and CGT (bias = -0.45 mm, SD = 0.32 mm, p < 0.000) 95.0% and 95.6% agreement were found, respectively, and in the FGT range only 93.3% (bias = -0.45 mm, SD = 0.32 mm, p < 0.000). The presence of positive correlations between WKT and SGT was shown. A positive correlation between SGT and WKT confirms the purpose of measuring these parameters for the evaluation of the GP. Both the ultrasonic method and cone-beam computed tomography combined with intraoral scanning and prosthetic-driven implant planning method were useful in determining gingival phenotype, however, the ultrasonic method was more accurate for measuring GT.

The occurrence of microplastic (MP) in food products, such as beverages in plastic bottles, is of high public concern. Existing analytical methods focus on the determination of particle numbers, requiring elaborate sampling tools, laboratory infrastructure and generally time-consuming imaging detection methods. A comprehensive routine analysis of MP in food products is still not possible. In the present work, we present the development of a smart filter crucible as sampling and detection tool. After filtration and drying of the filtered-off solids, a direct determination of the MP mass content from the crucible sample can be done by thermal extraction desorption gas chromatography mass spectroscopy (TED-GC/MS). The new filter crucible allows a filtration of MP down to particle sizes of 5 µm. We determined MP contents below 0.01 µg/L up to 2 µg/L, depending on beverages bottle type. This may be directly related to the bottle type, especially the quality of the plastic material of the screw cap. Dependent on the plastic material, particle formation increases due to opening and closing operations during the use phase. However, we have also found that some individual determinations of samples were subjected to high errors due to random events. A conclusive quantitative evaluation of the products is therefore not possible at present.

BACKGROUND Two clinical parameters, the gingival thickness (GT) and the width of keratinized tissue (WKT), describe the gingival phenotype, which is defined as the 3-dimensional volume of the gingiva. The periodontal phenotype additionally includes the thickness of the labial plate of the alveolar crest (TLPAC). MATERIAL AND METHODS Thirty patients with healthy periodontium on the upper canines and incisors underwent measurements for crestal, supracrestal, free gingival thickness (FGT), the alveolar crest-gingival margin (AC-GM), alveolar crest-cementoenamel junction distance, and the TLPAC at 2, 4, and 8 mm apically from the edge of the alveolar crest using cone-beam computed tomography (CBCT) with computer-aided design and prosthetic-driven implant planning technology. For each tooth, the gingival and periodontal phenotype was evaluated on the basis of the gingival thickness, width of keratinized tissue (WKT), and TLPAC measurements. Each patient's periodontal phenotype was evaluated according to the coronal width/length ratio of both the upper central incisors. RESULTS The dentogingival units had varying average values for the 3 periodontal phenotypes (thin phenotype: FGT 0.65±0.06 mm, WKT 4.85±1.18 mm, AC-GM 3.17±0.64 mm, TLPAC2 0.66±0.28 mm; medium phenotype: FGT 0.87±0.07 mm, WKT 5.49±1.23 mm, AC-GM 3.36±0.65 mm, TLPAC2 0.76±0.37 mm; and thick phenotype: FGT 1.20 mm, WKT 6.00 mm, AC-GM 3.90 mm, TLPAC2 0.90 mm). Positive correlations were seen among WKT, FGT, AC-GM, and TLPAC2. CONCLUSIONS Positive correlations between the FGT and WKT, and the AC-GM distance confirm that measurements using CBCT with computer-aided design and prosthetic-driven implant planning technology can evaluate the gingival phenotype and TLPAC2 for the periodontal phenotype.

Background: The aim of the study was to analyse changes in the size of the corpus callosum (CC) depending on age and sex and to establish the reference values of the morphometric indices of the CC in the Polish population., Materials and Methods: The results of magnetic resonance studies of 1108 patients performed in the years 2010-2014 were analysed. Two independent radiologists evaluated cerebral images to exclude deviations from normal state. In patients divided according to sex and to 10 age groups, measurements of CC and brain dimensions were made and morphometric indices were calculated., Results: The results of measurements related to the following parameters: lengths of longitudinal cross-section of CC (CD), CC thickness in the narrowest place - isthmus (EF), the largest linear dimension of the brain from the frontal pole to the occipital pole (AB), the longitudinal cross-section area of the CC (A1) and cerebral cross-section area (A2) as well as CD/AB and A1/A2 ratios are summarised in 7 figures and 3 tables., Conclusions: It was demonstrated, that in all age groups there are statistically significant differences in the values of the analysed parameters and ratios of CC size. It was indicated, that there are no statistically significant differences between men and women in the CD, EF, and A1 parameters related to CC size, and the profiles of variations of these parameters are very similar. It was proved that the- re are statistical differences between women and men in parameters/indicators concerning of the brain size.

In sodium channelopathies, a severe fixed myopathy caused by a dominant mutation is rare. We describe two unrelated patients with a novel variant, p.Ile1455Thr, with phenotypes of paramyotonia in one case and fixed proximal myopathy with latent myotonia in another. In-vitro whole cell patch-clamp studies show that the mutation slows inactivation and accelerates recovery, in line with other paramyotonia variants with destabilized fast inactivation as pathomechanism. Additionally, p.IleI1455 causes a loss-of-function by reduced membrane insertion, right-shift of activation, and slowed kinetics. Molecular dynamics simulations comparing wild type and mutant Nav1.4 showed that threonine substitution hindered D4S4 mobility in response to membrane depolarization, consistent with effects of the mutation on channel inactivation. The fixed myopathy is likely to be associated to gain-of-function leading to sodium accumulation, regional edema, T-tubular swelling and mitochondrial stress. A possible contribution of the loss-of-function features towards myotonia and myopathy is discussed., (Copyright © 2016. Published by Elsevier B.V.)

Essential tremor (ET) is the most prevalent movement disorder, affecting millions of people in the USA. Although a positive family history is one of the most important risk factors for ET, the genetic causes of ET remain unknown. In an attempt to identify genetic causes for ET, we performed whole-exome sequencing analyses in a large Spanish family with ET, in which two patients also developed epilepsy. To further assess pathogenicity, site-directed mutagenesis, mouse and human brain expression analyses, and patch clamp techniques were performed. A disease-segregating mutation (p.Gly1537Ser) in the SCN4A gene was identified. Posterior functional analyses demonstrated that more rapid kinetics at near-threshold potentials altered ion selectivity and facilitated the conductance of both potassium and ammonium ions, which could contribute to tremor and increase susceptibility to epilepsy, respectively. In this report, for the first time, we associated the genetic variability of SCN4A with the development of essential tremor, which adds ET to the growing list of neurological channelopathies., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The lysis/lysogeny switch of bacteriophage lambda serves as a paradigm for binary cell fate decision, long-term maintenance of cellular state and stimulus-triggered switching between states. In the literature, the system is often referred to as "bistable." However, it remains unclear whether this term provides an accurate description or is instead a misnomer. Here we address this question directly. We first quantify transcriptional regulation governing lysogenic maintenance using a single-cell fluorescence reporter. We then use the single-cell data to derive a stochastic theoretical model for the underlying regulatory network. We use the model to predict the steady states of the system and then validate these predictions experimentally. Specifically, a regime of bistability, and the resulting hysteretic behavior, are observed. Beyond the steady states, the theoretical model successfully predicts the kinetics of switching from lysogeny to lysis. Our results show how the physics-inspired concept of bistability can be reliably used to describe cellular phenotype, and how an experimentally-calibrated theoretical model can have accurate predictive power for cell-state switching.

We studied a two-generation family presenting with conditions that included progressive permanent weakness, myopathic myopathy, exercise-induced contracture before normokalaemic periodic paralysis or, if localized to the tibial anterior muscle group, transient compartment-like syndrome (painful acute oedema with neuronal compression and drop foot). 23Na and 1H magnetic resonance imaging displayed myoplasmic sodium overload, and oedema. We identified a novel familial Ca(v)1.1 calcium channel mutation, R1242G, localized to the third positive charge of the domain IV voltage sensor. Functional expression of R1242G in the muscular dysgenesis mouse cell line GLT revealed a 28% reduced central pore inward current and a -20 mV shift of the steady-state inactivation curve. Both changes may be at least partially explained by an outward omega (gating pore) current at positive potentials. Moreover, this outward omega current of 27.5 nS/nF may cause the reduction of the overshoot by 13 mV and slowing of the upstroke of action potentials by 36% that are associated with muscle hypoexcitability (permanent weakness and myopathic myopathy). In addition to the outward omega current, we identified an inward omega pore current of 95 nS/nF at negative membrane potentials after long depolarizing pulses that shifts the R1242G residue above the omega pore constriction. A simulation reveals that the inward current might depolarize the fibre sufficiently to trigger calcium release in the absence of an action potential and therefore cause an electrically silent depolarization-induced muscle contracture. Additionally, evidence of the inward current can be found in 23Na magnetic resonance imaging-detected sodium accumulation and 1H magnetic resonance imaging-detected oedema. We hypothesize that the episodes are normokalaemic because of depolarization-induced compensatory outward potassium flux through both delayed rectifiers and omega pore. We conclude that the position of the R1242G residue before elicitation of the omega current is decisive for its conductance: if the residue is located below the gating pore as in the resting state then outward currents are observed; if the residue is above the gating pore because of depolarization, as in the inactivated state, then inward currents are observed. This study shows for the first time that functional characterization of omega pore currents is possible using a cultured cell line expressing mutant Ca(v)1.1 channels. Likewise, it is the first calcium channel mutation for complicated normokalaemic periodic paralysis.

Studying the 3D sub-cellular structure of living cells is essential to our understanding of biological function. However, tomographic imaging of live cells is challenging mainly because they are transparent, i.e., weakly scattering structures. Therefore, this type of imaging has been implemented largely using fluorescence techniques. While confocal fluorescence imaging is a common approach to achieve sectioning, it requires fluorescence probes that are often harmful to the living specimen. On the other hand, by using the intrinsic contrast of the structures it is possible to study living cells in a non-invasive manner. One method that provides high-resolution quantitative information about nanoscale structures is a broadband interferometric technique known as Spatial Light Interference Microscopy (SLIM). In addition to rendering quantitative phase information, when combined with a high numerical aperture objective, SLIM also provides excellent depth sectioning capabilities. However, like in all linear optical systems, SLIM's resolution is limited by diffraction. Here we present a novel 3D field deconvolution algorithm that exploits the sparsity of phase images and renders images with resolution beyond the diffraction limit. We employ this label-free method, called deconvolution Spatial Light Interference Tomography (dSLIT), to visualize coiled sub-cellular structures in E. coli cells which are most likely the cytoskeletal MreB protein and the division site regulating MinCDE proteins. Previously these structures have only been observed using specialized strains and plasmids and fluorescence techniques. Our results indicate that dSLIT can be employed to study such structures in a practical and non-invasive manner.

Determining the growth patterns of single cells offers answers to some of the most elusive questions in contemporary cell biology: how cell growth is regulated and how cell size distributions are maintained. For example, a linear growth in time implies that there is no regulation required to maintain homeostasis; an exponential pattern indicates the opposite. Recently, there has been great effort to measure single cells using microelectromechanical systems technology, and several important questions have been explored. However, a unified, easy-to-use methodology to measure the growth rate of individual adherent cells of various sizes has been lacking. Here we demonstrate that a newly developed optical interferometric technique, known as spatial light interference microscopy, can measure the cell dry mass of many individual adherent cells in various conditions, over spatial scales from micrometers to millimeters, temporal scales ranging from seconds to days, and cell types ranging from bacteria to mammalian cells. We found evidence of exponential growth in Escherichia coli, which agrees very well with other recent reports. Perhaps most importantly, combining spatial light interference microscopy with fluorescence imaging provides a unique method for studying cell cycle-dependent growth. Thus, by using a fluorescent reporter for the S phase, we measured single cell growth over each phase of the cell cycle in human osteosarcoma U2OS cells and found that the G2 phase exhibits the highest growth rate, which is mass-dependent and can be approximated by an exponential.

Sphingosine 1-phosphate lyase (S1PL) has been characterized as a novel target for the treatment of autoimmune disorders using genetic and pharmacological methods. Medicinal chemistry efforts targeting S1PL by direct in vivo evaluation of synthetic analogues of 2-acetyl-4(5)-(1(R),2(S),3(R),4-tetrahydroxybutyl)-imidazole (THI, 1) led to the discovery of 2 (LX2931) and 4 (LX2932). The immunological phenotypes observed in S1PL deficient mice were recapitulated by oral administration of 2 or 4. Oral dosing of 2 or 4 yielded a dose-dependent decrease in circulating lymphocyte numbers in multiple species and showed a therapeutic effect in rodent models of rheumatoid arthritis (RA). Phase I clinical trials indicated that 2, the first clinically studied inhibitor of S1PL, produced a dose-dependent and reversible reduction of circulating lymphocytes and was well tolerated at dose levels of up to 180 mg daily. Phase II evaluation of 2 in patients with active rheumatoid arthritis is currently underway.

During nearly a decade of research dedicated to the study of sphingosine signaling pathways, we identified sphingosine-1-phosphate lyase (S1PL) as a drug target for the treatment of autoimmune disorders. S1PL catalyzes the irreversible decomposition of sphingosine-1-phosphate (S1P) by a retro-aldol fragmentation that yields hexadecanaldehyde and phosphoethanolamine. Genetic models demonstrated that mice expressing reduced S1PL activity had decreased numbers of circulating lymphocytes due to altered lymphocyte trafficking, which prevented disease development in multiple models of autoimmune disease. Mechanistic studies of lymphoid tissue following oral administration of 2-acetyl-4(5)-(1(R),2(S),3(R),4-tetrahydroxybutyl)-imidazole (THI) 3 showed a clear relationship between reduced lyase activity, elevated S1P levels, and lower levels of circulating lymphocytes. Our internal medicinal chemistry efforts discovered potent analogues of 3 bearing heterocycles as chemical equivalents of the pendant carbonyl present in the parent structure. Reduction of S1PL activity by oral administration of these analogues recapitulated the phenotype of mice with genetically reduced S1PL expression.

A 3D quantitative structure-activity relationship study for inhibition of calcium-sensing receptor in the aryloxypropanolamine series predicted that these molecules adopt a U-shaped conformation with pi-stacking between the two aromatic rings. This hypothesis led to the discovery of novel 1-arylmethyl pyrrolidin-2-yl ethanol amines capable of antagonizing the calcium-sensing receptor with potency comparable to that of NPS-2143.

We calculate the temperature dependence of the fluorescence Stokes shift and the fluorescence decay time in linear Frenkel exciton systems resulting from the thermal redistribution of exciton population over the band states. The following factors, relevant to common experimental conditions, are accounted for in our kinetic model: (weak) localization of the exciton states by static disorder, coupling of the localized excitons to vibrations in the host medium, a possible nonequilibrium of the subsystem of localized Frenkel excitons on the time scale of the emission process, and different excitation conditions (resonant or nonresonant). A Pauli master equation, with microscopically calculated transition rates, is used to describe the redistribution of the exciton population over the manifold of localized exciton states. We find a counterintuitive nonmonotonic temperature dependence of the Stokes shift. In addition, we show that depending on experimental conditions, the observed fluorescence decay time may be determined by vibration-induced intraband relaxation, rather than radiative relaxation to the ground state. The model considered has relevance to a wide variety of materials, such as linear molecular aggregates, conjugated polymers, and polysilanes., ((c) 2004 American Institute of Physics.)

We model the optical dynamics in linear Frenkel exciton systems governed by scattering on static disorder and lattice vibrations and calculate the temperature dependent fluorescence spectrum and lifetime. The fluorescence Stokes shift shows a nonmonotonic behavior with temperature, which derives from the interplay of the local band-edge level structure and thermal equilibration. The model yields excellent fits to experiments performed on linear dye aggregates.

Continuing structure-activity studies were performed on the 2,3,4, 5-tetrahydro-1-(imidazol-4-ylalkyl)-1,4-benzodiazepine farnesyltransferase (FT) inhibitors. These studies demonstrated that a 3(R)-phenylmethyl group, a hydrophilic 7-cyano group, and a 4-sulfonyl group bearing a variety of substituents provide low-nanomolar FT inhibitors with cellular activity at concentrations below 100 nM. Maximal in vivo activity in the mutated K-Ras bearing HCT-116 human colon tumor model was achieved with analogues carrying hydrophobic side chains such as propyl, phenyl, or thienyl attached to the N-4 sulfonyl group. Several such compounds achieved curative efficacy when given orally in this model. On the basis of its excellent preclinical antitumor activity and promising pharmacokinetics, compound 20 (BMS-214662, (R)-7-cyano-2,3,4, 5-tetrahydro-1-(1H-imidazol-4-ylmethyl)-3-(phenylmethyl)-4-(2-thie nyl sulfonyl)-1H-1,4-benzodiazepine) has been advanced into human clinical trials.