Extraction Artifact Research Articles

No Evidence Was Found for the Presence of Terreolides, Terreumols or Saponaceolides H-S in the Fruiting Bodies of Tricholoma terreum (Basidiomycota, Agaricales).

Two different collections of the gilled wild fungus Tricholoma terreum, collected in Italy, were subjected to phytochemical analysis. The fungal material was confidently identified by analysis of the ITS genomic sequences. Using both HR-LC-MS and NMR techniques, no evidence was found for the presence in the fruiting bodies of terreolides, terreumols or saponaceolides H-S, in striking contrast with the isolation of these terpenoids by Chinese authors from a mushroom collected in France and identified as T. terreum. The main cytotoxic terpenoid identified and isolated from the extracts of the specimens investigated in this work was the C30 derivative saponaceolide B, which had been previously isolated from T. saponaceum and other T. terreum collections. Although saponaceolide B is a rather labile molecule, easily degradable by heat or in acidic conditions, our study indicated that none of the extraction protocols used produced saponaceolide H-S or terreolide/terreumol derivatives, thus excluding the possibility that the latter compounds could be extraction artifacts. Considered together, these findings point to the need for the unambiguous identification of mushroom species belonging to the complex genus Tricholoma, characterized by high variability in the composition of metabolites. Moreover, based on our data, T. terreum must be considered an edible mushroom.

Phytochemical characterization and biological activities of Stenomesson miniatum bulb extract, a medicinal plant of the Andes

Fresh bulbs of Stenomesson miniatum, a plant belonging to the Amaryllidaceae family with a poorly investigated phytochemical profile, were traditionally employed by Andean healers to treat tumors and abscesses. The aims of this study were to characterize the extract from the bulbs of S. miniatum and to test its cytotoxic and antibacterial potential. A previous structural study of the major extract constituents was extended to include the minor components by means of 13C-NMR-based dereplication. Cytotoxic activities were evaluated on A431 human epidermoid carcinoma cells through a metabolic assay and on Jurkat human acute T-leukemia cells through a cell-impermeant fluorescent nuclear probe. Antibacterial assays were carried out against Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes by using a standardized broth microdilution method. Eleven known Amaryllidaceae alkaloids were identified together with another compound determined as being an extraction artefact. The alkaloid-enriched extract showed good cytotoxic activity against both tumor cell lines, reaching an IC50 of 3.3 µg/mL against A431 cells and of 10.9 µg/mL against Jurkat cells. Biological assays carried out on single fractions showed that activity can be attributed to the presence of pretazettine and haemanthamine. Conversely, no antibacterial activities were recorded for any of the samples.

Forensic Web Analysis on The Latest Version of Whatsapp Browser

With the rapid growth of technology and the increasing number of smartphone users, social media applications have proliferated. Among them, WhatsApp has emerged as the most widely used application, with over a quarter of the world's population using it since 2009. To meet the increasing customer demands, WhatsApp has introduced a browser version, which has undergone continuous updates and improvements. The latest version of WhatsApp exhibits significant differences in features and settings compared to its predecessors, particularly in conversations, images, video recordings, and other aspects. Consequently, this research focuses on analyzing artifacts that can aid in forensic investigations. The study aims to extract artifacts related to conversation sessions, as well as media data such as audio files, contact numbers, photos, videos, and more. To achieve these objectives, various forensic tools will be employed to assist in the artifact search within the WhatsApp browser. The research adopts the NIST framework and utilizes forensic techniques like Autopsy and FTK Imager to read encrypted backup database files. These files contain valuable information such as deleted conversations, phone logs, photos, videos, and other data of interest. Analyzing the artifacts from the WhatsApp browser version contributes to forensic activities, providing valuable insights into the evidence that can be obtained from conversations and media files. By leveraging forensic tools and techniques, forensic practitioners can effectively retrieve and analyze data from the encrypted backup database files. In summary, this research explores the artifacts within the WhatsApp browser version, sheds light on its distinct features, and presents a forensic approach utilizing the NIST framework and forensic tools like Autopsy and FTK Imager to examine encrypted backup database files containing crucial deleted data, conversations, and media files.

Do preoperative factors and implant design features influence humeral stem extraction efforts?

Variations in humeral component designs in hemiarthroplasty and anatomic total shoulder arthroplasty cases can impact the degree of difficulty during a revision surgery that necessitates the removal of the humeral stem. However, no metric exists to define stem extraction effort nor to identify associated factors that contribute to extraction difficulty. The purpose of this study is to describe a method to quantify stem extraction difficulty and to define features that will impact the effort during stem removal. This was a retrospective review of 58 patients undergoing revision of hemiarthroplasty or anatomic total shoulder arthroplasty requiring stem extraction. Each included patient had existing preoperative radiographic examination, an intraoperative video of the stem removal process, and explants available for analysis by 3 surgeons. The following factors were assessed for the impact on extraction difficulty: (1) preoperative features such as cement use, fill of proximal humerus, and stem design features; (2) intraoperative data on extraction time and bone removal; and (3) postoperative findings related to extraction artifacts (EAs). A scoring system was established to distinguish easy (Easy group) and difficult (Difficult group) stem removal cases and further used to identify the features that may affect intraoperative difficulty of stem removal. The Difficult group accounted for 26% (15/58) of the study population with an 18-minute average stem extraction time, average EA count of 69, and 35 mm of bone removed. The Easy group accounted for 74% (43/58) of patients, with a 4-minute average extraction time, average EA count of 23, and 10 mm of bone removed. Logistic regression model was able to correctly classify 82% of the cases, explaining 26.7% of the variance in humeral stem removal with cement and proximal coating variables. The likelihood of cemented stem removal being difficult is 5 times greater compared to an uncemented stem, and having proximal coating doubles the likelihood of a difficult stem removal compared to cases with no coating. Quantifying stem extraction difficulty is possible with intraoperative video as well as explant analysis. Preoperative features of the fixation type and specific features of stem design such as proximal coating will impact difficulty of stem extraction.

Constituents of Croton megalocarpus with Potential Anti-HIV Activity.

Reported herein is an anti-HIV monochlorinated compound, 1β-acetoxy-3β-chloro-5α,6α-dihydroxycrotocascarin L (1), of the rare crotofolane diterpenoid class. Compound 1, a suspected artifact of extraction, along with the previously undescribed 11β-acetoxycrotocascarin L (2) and a known compound, crotocascarin K (3), were isolated from the bark of Croton megalocarpus, a Kenyan oil-producing seed crop. Compounds 1 and 3 inhibited HIV-1 replication with IC50 values of 28 and 5.5 nM, respectively. Furthermore, both compounds lacked cytotoxicity toward MT-4 cells and FM-55-M1 cells at concentrations of up to 50 μM. Compounds 1 and 3 were both found to inhibit HIV-1 protease.

AutoProfile: Towards Automated Profile Generation for Memory Analysis

Despite a considerable number of approaches that have been proposed to protect computer systems, cyber-criminal activities are on the rise and forensic analysis of compromised machines and seized devices is becoming essential in computer security. This article focuses on memory forensics, a branch of digital forensics that extract artifacts from the volatile memory. In particular, this article looks at a key ingredient required by memory forensics frameworks: a precise model of the OS kernel under analysis, also known as profile . By using the information stored in the profile, memory forensics tools are able to bridge the semantic gap and interpret raw bytes to extract evidences from a memory dump. A big problem with profile-based solutions is that custom profiles must be created for each and every system under analysis. This is especially problematic for Linux systems, because profiles are not generic : they are strictly tied to a specific kernel version and to the configuration used to build the kernel. Failing to create a valid profile means that an analyst cannot unleash the true power of memory forensics and is limited to primitive carving strategies. For this reason, in this article we present a novel approach that combines source code and binary analysis techniques to automatically generate a profile from a memory dump, without relying on any non-public information. Our experiments show that this is a viable solution and that profiles reconstructed by our framework can be used to run many plugins, which are essential for a successful forensics investigation.

Duck Hunt: Memory forensics of USB attack platforms

To explore the memory forensic artifacts generated by USB-based attack platforms, we analyzed two of the most popular commercially available devices, Hak5's USB Rubber Ducky and Bash Bunny. We present two open source Volatility plugins, usbhunt and dhcphunt, which extract artifacts generated by these USB attacks from Windows 10 system memory images. Such artifacts include driver-related diagnostic events, unique device identifiers, and DHCP client logs. Our tools are capable of extracting metadata-rich Windows diagnostic events generated by any USB device. The device identifiers presented in this work may also be used to definitively detect device usage. Likewise, the DHCP logs we carve from memory may be useful in the forensic analysis of other network-connected peripherals. We also quantify how long these artifacts remain recoverable in memory. Our experiments demonstrated that some Indicators of Compromise (IOCs) remain in memory for at least 24 h.

Finger Vein Pulsation-Based Biometric Recognition

Finger vein has become an appealing biometric trait due to its intrinsic nature, contactless acquisition and anti-spoofing capability when compared to other dominant biometric traits. The state-of-the-art intrinsic recognition derives vein patterns based on either curvature values, line tracking or deep neural networks. However, these methods extract artifacts such as noise, breaks and texture along with veins due to the problems such as irregular shading, poor contrast and blurriness in NIR images which affect the recognition accuracy. To deal with these issues, we propose a novel acquisition mechanism for vein patterns based on the pulsation of the veins. We propose to capture the pulsations from vein videos to accurately isolate the vein patterns. Besides, the proposed framework has an inherent method of detecting liveness along with recognition of the finger vein. To the best of our knowledge, this is the first work that utilizes the finger vein pulsations for biometric recognition. We acquired a finger vein video dataset, from 320 subjects, to evaluate the proposed method. The experimental results indicate that the proposed approach has a better recognition performance compared to the existing image-based approaches with an EER (%) of 0.8 and a recognition accuracy of 96.35%.

A Systematic Approach to Dissection of the Equine Brain-Evaluation of a Species-Adapted Protocol for Beginners and Experts.

Introduction of new imaging modalities for the equine brain have refocused attention on the horse as a natural model for ethological, neuroanatomical, and neuroscientific investigations. As opposed to imaging studies, strategies for equine neurodissection still lack a structured approach, standardization and reproducibility. In contrast to other species, where adapted protocols for sampling have been published, no comparable guideline is currently available for equids. Hence, we developed a species-specific slice protocol for whole brain vs. hemispheric dissection and tested its applicability and practicability in the field, as well as its neuroanatomical accuracy and reproducibility. Dissection steps are concisely described and depicted by schematic illustrations, photographs and instructional videos. Care was taken to show the brain in relation to the raters' hands, cutting devices and bench surface. Guidance is based on a minimum of external anatomical landmarks followed by geometric instructions that led to procurement of 14 targeted slabs. The protocol was performed on 55 formalin-fixed brains by three groups of investigators with different neuroanatomical skills. Validation of brain dissection outcomes addressed the aptitude of slabs for neuroanatomical studies as opposed to simplified routine diagnostic purposes. Across all raters, as much as 95.2% of slabs were appropriate for neuroanatomical studies, and 100% of slabs qualified for a routine diagnostic setting. Neither autolysis nor subfixation significantly affected neuroanatomical accuracy score, while a significant negative effect was observed with brain extraction artifacts. Procedure times ranged from 14 to 66 min and reached a mean duration of 23.25 ± 7.93 min in the last of five trials in inexperienced raters vs. 16 ± 2.83 min in experts, while acceleration of the dissection did not negatively impact neuroanatomical accuracy. This protocol, derived analogously to the consensus report of the International Veterinary Epilepsy Task Force in dogs and cats, allows for systematic, quick and easy dissection of the equine brain, even for inexperienced investigators. Obtained slabs feature virtually all functional subcompartments at suitable planes for both diagnostic and neuroscientific investigations and complement the data obtained from imaging studies. The instructive protocol and brain dissection videos are available in Supplementary Material.

Separation of movement direction concepts based on independent component analysis algorithm, linear discriminant analysis, deep belief network, artificial and fuzzy neural networks

Brain signals have various scientific and practical applications, such as Medical Science, Cognitive Science, Neuroscience, and Brain Computer Interfaces. Brain signal analysis is faced with complex challenges including small sample size, high dimensionality and noisy signals. Because of the non-stationarity of brain signals and the impacts of mental states on brain function, brain signals are associated with an inherent uncertainty. In this study, it is tried to present a plausible method for detecting and distinguishing the directions from EEG signals. Recording single-polarized signals was carried out utilizing a 19-channel cap Micromed device with the use of Cz as reference electrode. The statistical population used involved ten 25–35 year old male volunteers. The designed task consisted of 24 slides of up, down, left and right directions. After preprocessing level, ICA algorithm was employed to extract artifacts, to decrease signal dimension and to determine the target signal. In feature extraction section, AR coefficients extracted to feed the ANN, FNN and LDA. Data for Deep Belief Network provided from Autoregressive power spectral density estimate with order of 20 employed on the data set.Classifiers’ results reveal that 2.5 s time window leads to the best separation accuracy.DBN surprisingly leads to the highest level of accuracy in comparison to the other proposed methods.Based on the 10-fold Cross Validation, the performance of the classifiers measured in terms of accuracy, sensitivity and specificity. The obtained average accuracies for LDA, ANN, FNN and DBN respectively are 61.86 ± 1.69 %, 57.18 ± 1.88 %, 66.79 ± 2.14 % and 91.06 ± 0.68.

Characterization Of Liver Metabolism By NMR‐Guided GC‐MS Methodology

Non‐Alcoholic Fatty liver disease (NAFLD), Non‐alcoholic Steatohepatitis (NASH), liver cirrhosis and liver cancer affect a combined 80–100 million Americans [Perumpail et al. World J Gastroenterology. 2017, 23(47), 8263]. In order to better diagnose these conditions and monitor treatment progression, several metabolomics approaches have been developed. Amongst these, Mass Spectrometry (MS) and Nuclear Magnetic Resonance (NMR) have been used extensively.In this study, a recently developed method of metabolic profiling coined NMR‐Guided LC‐MS is assessed for its ability to accurately measure metabolites. [Nagana Gowda et al. Anal. Chem. 2018, 90(3), 2001]. The principle of NMR‐Guided MS is to obtain a ratio of a metabolites mass spectral intensity to its assigned concentration from 1H NMR spectra in a reference sample. This ratio is then applied to mass spectral intensities for in other samples to assign a metabolites concentration. For NMR‐Guided MS to be applicable to a metabolite of interest the variance between NMR‐Guided MS and NMR concentrations must be low and constant over a concentration range of biological interest. In this case, we apply a similar normalization methodology to GC‐MS to assess the technical possibility of producing quantitative GC‐MS approaches to metabolomic analysis.To achieve the biological range of interest we extracted metabolites from ex vivo C57/BLKS perfused mouse livers under fed and fasted conditions. Additionally, two common extractions methods, perchloric acid extraction (PCA) and acetonitrile‐Isopropanol‐water (ACN/ISO/H2O) were compared.A significant fraction of high concentration compounds, including lactate and alanine, amino acids such as aspartate and glycine, and some TCA cycle intermediates such as succinate had low variance across fed and fasted samples between NMR‐Guided GC‐MS and NMR. Branched chain amino acids had greater variance by NMR‐Guided GC‐MS than GC‐MS alone when compared to NMR. In the case of β‐Hydroxybutyrate (BHB), the variance between NMRGuided GC‐MS and NMR was acceptable when extracted by PCA but not ACN/ISO/H2O for both tissue extracts and standard mixtures. BHB concentrations assigned by GC‐MS have a high variance relative to NMR regardless of the extraction method. However, for the majority of metabolites, differences in variance between extractions and assignment methods were subtle for livers and apparent only at concentration extremes of standards (Figure I).Altogether the data presented here provides insight about the comparability of GC‐MS and NMR systems, with excellent agreement observed between the methods across most metabolites. We have also demonstrated measurable extraction artifacts between PCA and ACN/ISO/H2O methods for some metabolites. In conclusion, NMR‐Guided GC‐MS may lend to more rapid and accurate metabolite measurements, broadening the swatch of applicability of the relatively inexpensive GC‐MS platform to metabolomics profiling.Support or Funding InformationNIH R01DK105346% coefficient of variance (% CV) for assigned concentrations by GC‐MS or NMR‐Guided MS compared to NMR assigned concentrations are presented as heat maps. The top panel represent standard samples across a range of 1 to 18 μg per metabolite extracted by PCA or ACN/ISO/H2O. While the bottom panel represents fed and fasted liver tissues extracted by PCA or ACN/ISO/H2O. Histograms in the middle provide density information on the %CVs and are color matched to their respective panels.Figure 1

Personal Data and Power Asymmetries in U.S. Collegiate Sports Teams

Collaborations increasingly draw on personal data. We examine personal-data-supported collaborations in a high stakes, high-performance environment: collegiate sports. We conducted 22 interviews with people from four common roles within collegiate sports teams: athletes, sport coaches, athletic trainers, and strength and conditioning coaches. Using boundary negotiating artifacts as a lens for analysis, we describe an ecology of personal data in collaborations among these four roles. We use this ecology to highlight tensions and foreground issues of power asymmetry in these collaborations. To characterize these power asymmetries in the collaborative use of personal data, we propose an extension of boundary negotiating artifacts: extraction artifacts.

Evidence for the Existence of Humic Acids in Peat Soils Based on Solid‐State 13C NMR

Humic extracts, in particular humic acids, of organic‐rich peat soils were examined by solid‐state 13C nuclear magnetic resonance (NMR) and shown to be integral components of the peat, contrary to recent suggestions that humic materials are artifacts of alkali extraction. The authenticity of humic substances is demonstrated by recombining the various humic fractions and comparing the NMR spectrum of the recombined peat with the original untreated peat sample. Even though significant NMR‐determined structural differences exist between humic acids and the insoluble humin fractions, the recombination reproduces the original unextracted peat quite well. Applying a biopolymer mixing model to the spectra shows that humic acids have a high proportion of char‐like material that is interpreted as being derived from noncombustion polymerization or secondary synthesis during humification, a process that has been challenged by a recent soil formation model.Core Ideas Solid‐state 13C NMR of soils isolated by dilute alkali proves the existence of humic acids. Molecular mixing model and physical reconstitution both confirm the alkali extracts are real. More char‐like structures in humic acids than humin suggests secondary synthesis formation.

Do preoperative radiographs help predict intraoperative challenges in revision surgery after previous shoulder hemiarthroplasty?

This study compares preoperative radiographic evaluation with intraoperative video and explant data in patients undergoing revision of a hemiarthroplasty. From 2004 to 2017, 182 shoulder hemiarthroplasties underwent revision to reverse shoulder arthroplasty for symptomatic failure. Preoperative radiographs were evaluated for stem fixation, stability, and glenohumeral registry. Intraoperative videos (n = 48) were evaluated for humeral component stability and bone loss after humeral stem extraction. All explants (n = 83) were reviewed for humeral head wear patterns and extraction artifacts (EAs). A well-fixed stem was reliably identified on radiographs as well fixed (true-negative rate, 95%). Of cemented implants, 94% (97 of 103) were radiographically stable and 90% (18 of 20) were stable on intraoperative video. Significant proximal humeral bone loss was identified after cemented stem extraction in 83% of cases, and severe EAs were noted in 28% (14 of 50). Of uncemented implants, 95% (75 of 79) were radiographically stable and 96% (24 of 25) were operatively stable. Significant proximal humeral bone loss was identified after extraction in 36% of cases (9 of 25) (P = .001). Severe EAs were seen in 13% of explanted stems (3 of 23). Eccentrically worn humeral head explants were associated with eccentric glenohumeral registry in 84% of cases (P = .0075). Preoperative radiographs for revision of a failed hemiarthroplasty help identify well-fixed stems and predict humeral bone loss during extraction. Cemented stems will have more EAs and result in greater bone loss than uncemented stems. Glenohumeral registry can help to predict humeral head wear. Eccentric registry leads to eccentric humeral head wear in 84% of cases.

Method of Reconstruction the Intact Surface for Surgical Accesses

The aim of this work lies in designing software used for preoperative planning of the surgical access risk. In order to obtain a realistic and useful simulation we focused our study on the physical modeling of the brain targeting and on the maneuvers of the surgical instruments. A new method of intact surface construction, which will assist in accurate neurosurgical planning, was discussed. Moreover, the three-dimensional model and its visualization were described. This visualization method allows of combining the calculated data about the surgical intervention risks with the geometrical data describing patient's head. Therefore, this methodology will help to build an intelligent system that has the ability of selection the best approach of surgical intervention access. The current technique is based on geometrical synthetic object creation, this object “in next stages of the surgical planning approach” would be applied directly to the data describing the risks of surgical access, and this in turn will allow estimating the real risk value of the surgical access. The advantage of this method is that the creation of the object is based on surgical access approach. The best surgical access is based on finding the smallest distance of surgical intervention toward the target, taking into the account the reduction of brain tissue damage. The method of the intact vertex can significantly reduce the amount of memory overloading, also a method of filtration used to extract artifacts resulting in unreal vertices, caused in rendering errors and memory overloading, was used. Also, using data describing the correlation between the object vertices allows arifacts filtration without any need for additional transformations. All that improves the rendering procedure and the accuracy of the surgical intervention by 30%.

Heterogeneity of free and occluded bitumen in a natural maturity sequence from Oligocene Lake Enspel

Sedimentation in Oligocene Lake Enspel was rapidly terminated by a basaltic lava flow. This introduced a preservational barrier while imparting a ‘natural flash pyrolysis’, during which the organic matter in underlying stratigraphic units was subjected to rapid thermal maturation resulting in hydrocarbon generation. Samples from these strata exhibit a steep maturity gradient (0.25–1.07% optical vitrinite reflectance, or RO) over uniform organofacies. This offers the opportunity to investigate bitumen generation during rapid thermal maturation mechanistically, in particular the nature of Bitumen 2—occluded bitumen, which is only recoverable after the digestion of the mineral matrix and was frequently dismissed as an artifact of incomplete extraction. Elaborate sequential extraction of the contact metamorphic sequence of oil shales at Enspel revealed systematic changes in bitumen composition. These trend progressively towards those of occluded bitumen, which exhibits a systematically elevated thermal maturity, a higher degree of catalytic biomarker-rearrangement and the conspicuous absence of molecular signatures from vascular plants that are present in the free bitumen. One plausible explanation involves a contribution of allochthonous clay-adsorbed organic matter to Bitumen 2. This could represent a mixture of older reworked bitumen and an early-diagenetic snapshot of clay adsorbed organic matter. Alternatively, a close association of early-generated bitumen with clay minerals may have led to enhanced isomerization and catalytically influenced ‘uniformization’ of alkane signatures. Deviations from the expected relationships between various thermal maturity parameters suggest variable dependence on the time-pressure-temperature pathway (i.e. metamorphic facies). The maturation of organic matter likely behaves differently under a contact metamorphic regime or during rapid subsidence and exhumation, as compared to slow maturation during regional subsidence. Our data also suggest that geologically brief shallow intrusive or extrusive magmatism might not be as destructive to the sedimentary hydrocarbon inventory as hitherto thought. This study draws attention to the small-scale compositional heterogeneity of bitumen that can be studied using sequential extraction methods. More importantly, it suggests that occluded bitumen could potentially harbor information on organic matter that pre-dates in situ primary productivity and may be derived from allochthonous biomass and detrital input.

Identification of 21,22-Dehydroazaspiracids in Mussels ( Mytilus edulis) and in Vitro Toxicity of Azaspiracid-26.

Azaspiracids (AZAs) are marine biotoxins produced by the genera Azadinium and Amphidoma, pelagic marine dinoflagellates that may accumulate in shellfish resulting in human illness following consumption. The complexity of these toxins has been well documented, with more than 40 structural variants reported that are produced by dinoflagellates, result from metabolism in shellfish, or are extraction artifacts. Approximately 34 μg of a new AZA with MW 823 Da (AZA26 (3)) was isolated from blue mussels ( Mytilus edulis), and its structure determined by MS and NMR spectroscopy. AZA26, possibly a bioconversion product of AZA5, lacked the C-20-C-21 diol present in all AZAs reported thus far and had a 21,22-olefin and a keto group at C-23. Toxicological assessment of 3 using an in vitro model system based on Jurkat T lymphocyte cells showed the potency to be ∼30-fold lower than that of AZA1. The corresponding 21,22-dehydro-23-oxo-analogue of AZA10 (AZA28) and 21,22-dehydro analogues of AZA3, -4, -5, -6, -9, and -10 (AZA25, -48 (4), -60, -27, -49, and -61, respectively) were also identified by HRMS/MS, periodate cleavage reactivity, conversion from known analogues, and NMR (for 4 that was present in a partially purified sample of AZA7).

Facilitation and refractoriness of the electrically evoked compound action potential

In this study we aim to resolve the contributions of facilitation and refractoriness at very short pulse intervals. Measurements of the refractory properties of the electrically evoked compound action potential (ECAP) of the auditory nerve in cochlear implant (CI) users at inter pulse intervals below 300 μs are influenced by facilitation and recovery effects. ECAPs were recorded using masker pulses with a wide range of current levels relative to the probe pulse levels, for three suprathreshold probe levels and pulse intervals from 13 to 200 μs. Evoked potentials were measured for 21 CI patients by using the masked response extraction artifact cancellation procedure.During analysis of the measurements the stimulation current was not used as absolute value, but in relation to the patient's individual ECAP threshold. This enabled a more general approach to describe facilitation as a probe level independent effect. Maximum facilitation was found for all tested inter pulse intervals at masker levels near patient's individual ECAP threshold, independent from probe level. For short inter pulse intervals an increased N1P1 amplitude was measured for subthreshold masker levels down to 120 CL below patient's individual ECAP threshold in contrast to the recreated state.ECAPs recorded with inter pulse intervals up to 200 μs are influenced by facilitation and recovery. Facilitation effects are most pronounced for masker levels at or below ECAP threshold, while recovery effects increase with higher masker levels above ECAP threshold. The local maximum of the ECAP amplitude for masker levels around ECAP threshold can be explained by the mutual influence of maximum facilitation and minimal refractoriness.

WEB BROWSER FORENSICS: GOOGLE CHROME

Internet users use the web browser to perform various activities on the internet such as browsing internet, email, internet banking, social media applications, download files- videos etc. As web browser is the only way to access the internet and cybercrime criminal uses or target the web browser to commit the crime related to internet. It is very important for the digital forensic examiner to collect and analysis artifacts related to web browser usage of the suspect. There are various browsers available in the market such as Google Chrome, Internet Explorer, Firefox Mozilla, Safari and Opera etc, among which Google Chrome is very popular among the internet user community. Our literature survey shows that most of the researches used prefetch file and live memory analysis as source of information to extract artifacts. In this research paper, we analyzed default artifacts location, history, cookies, login data, topsides, shortcuts, user profile, prefetch file and RAM dump to collect artifacts related to internet activities on windows installed Google Chrome. The outcome of this research will serve to be a significant resource for law enforcement, computer forensic investigators, and the digital forensics research community.

Phospholipids of New Zealand Edible Brown Algae.

Edible brown algae have attracted interest as a source of beneficial allenic carotenoid fucoxanthin, and glyco- and phospholipids enriched in polyunsaturated fatty acids. Unlike green algae, brown algae contain no or little phosphatidylserine, possessing an unusual aminophospholipid, phosphatidyl-O-[N-(2-hydroxyethyl) glycine], PHEG, instead. When our routinely used technique of 31P-NMR analysis of phospholipids was applied to the samples of edible New Zealand brown algae, a number of signals corresponding to unidentified phosphorus-containing compounds were observed in total lipids. NI (negative ion) ESI QToF MS spectra confirmed the presence of more familiar phospholipids, and also suggested the presence of PHEG or its isomers. The structure of PHEG was confirmed by comparison with a synthetic standard. An unusual MS fragmentation pattern that was also observed prompted us to synthesise a number of possible candidates, and was found to follow that of phosphatidylhydroxyethyl methylcarbamate, likely an extraction artefact. An unexpected outcome was the finding of ceramidephosphoinositol that has not been reported previously as occurring in brown algae. An uncommon arsenic-containing phospholipid has also been observed and quantified, and its TLC behaviour studied, along with that of the newly synthesised lipids.