Konstruksjon av høytrykks-stigerør løfteklemme

Gruppen har påtatt seg en problemstilling fra firmaet WellPartner A/S. WellPartner er ett oljeservice selskap som holder til i Risavik utenfor Stavanger, der de har kontorer og verksted. De driver med utleie av personell og utstyr innenfor olje og gass bransjen. Blant annet driver de med utleie av stigerør systemer (riser), i den forbindelse har oppdragsgiver et helse, miljø og sikkerhets (hms) problem de ønsker løsning på. Wellpartner lagrer lengder med stigerør (riser jointer) i stabler inne på verkstedet. Håndtering av disse rørene på verkstedet utføres på en risikofylt måte med bruk av fiberstropper og mye klatring i stablene. WellPartner ønsker derfor å få en løsning på dette problemet, og ser for seg å få laget ett løfteredskap til riser. Hensikten er å eliminere all bruk av fiberstropper. Bruk av fiberstropper medfører mye klatring som igjen fører til risikofylt arbeid når rør skal stroppes opp for løft, både på bakkenivå og i høyden. For å komme frem til en best mulig løsning på problemet er det blitt utført en forstudie, samt risikoanalyser på løfte-operasjonen både med og uten bruk av løfteredskap. Disse ble utarbeidet for å få frem fordelene med ett spesialdesignet løfteredskap. Etter analysene ble det bestemt at Wellpartner trenger en løfteklemme (clamp) som kunne benyttes til riser håndtering. For å komme frem til en løsning som er best egnet for Wellpartner sin problemstilling, er det blitt utført en konseptstudie. Her ble 3 alternative løsninger drøftet opp mot hverandre, og valget falt på den løsningen som ble vurdert som best. Med tanke på konstruksjon og hms. Den valgte løsningen er et løfte clamp som er basert på en bjelke med 2 vribare løfteklaver, med manuell betjening og låsing. Dette ga oss et enkelt og sikkert design, med lite bevegelige deler og lite svake punkter. Resultatet er et robust design som er lett å vedlikeholde. Utstyret er konstruert og beregnet i Inventor, arbeids og sammenstillings tegninger er blitt utarbeidet. Alt arbeid er gjort i henhold til maskinforskriften. Dette for å sikre at løfte clampet kan sertifiseres som løfteredskap, om det skulle bli satt i produksjon. I forbindelse med at det skal være mulig å sertifisere clampet, er det også laget en bruksanvisning på norsk. Dette er et krav i henhold til maskinforskriften. I tillegg er det laget ett kostnadsestimat for produksjon av løfte clampet. Samt at optimal type overflatebehandling er utredet. Arbeidet som er nedlagt, gir Wellpartner svar på problemstillingen deres. Når denne oppgaven er overlevert, står Wellpartner selv fritt til å produsere utstyret og få det godkjent for løft

Konstruksjon av høytrykks-stigerør løfteklemme.

Gruppen har påtatt seg en problemstilling fra firmaet WellPartner A/S. WellPartner er ett oljeservice selskap som holder til i Risavik utenfor Stavanger, der de har kontorer og verksted. De driver med utleie av personell og utstyr innenfor olje og gass bransjen. Blant annet driver de med utleie av stigerør systemer (riser), i den forbindelse har oppdragsgiver et helse, miljø og sikkerhets (hms) problem de ønsker løsning på. Wellpartner lagrer lengder med stigerør (riser jointer) i stabler inne på verkstedet. Håndtering av disse rørene på verkstedet utføres på en risikofylt måte med bruk av fiberstropper og mye klatring i stablene. WellPartner ønsker derfor å få en løsning på dette problemet, og ser for seg å få laget ett løfteredskap til riser. Hensikten er å eliminere all bruk av fiberstropper. Bruk av fiberstropper medfører mye klatring som igjen fører til risikofylt arbeid når rør skal stroppes opp for løft, både på bakkenivå og i høyden. For å komme frem til en best mulig løsning på problemet er det blitt utført en forstudie, samt risikoanalyser på løfte-operasjonen både med og uten bruk av løfteredskap. Disse ble utarbeidet for å få frem fordelene med ett spesialdesignet løfteredskap. Etter analysene ble det bestemt at Wellpartner trenger en løfteklemme (clamp) som kunne benyttes til riser håndtering. For å komme frem til en løsning som er best egnet for Wellpartner sin problemstilling, er det blitt utført en konseptstudie. Her ble 3 alternative løsninger drøftet opp mot hverandre, og valget falt på den løsningen som ble vurdert som best. Med tanke på konstruksjon og hms. Den valgte løsningen er et løfte clamp som er basert på en bjelke med 2 vribare løfteklaver, med manuell betjening og låsing. Dette ga oss et enkelt og sikkert design, med lite bevegelige deler og lite svake punkter. Resultatet er et robust design som er lett å vedlikeholde. Utstyret er konstruert og beregnet i Inventor, arbeids og sammenstillings tegninger er blitt utarbeidet. Alt arbeid er gjort i henhold til maskinforskriften. Dette for å sikre at løfte clampet kan sertifiseres som løfteredskap, om det skulle bli satt i produksjon. I forbindelse med at det skal være mulig å sertifisere clampet, er det også laget en bruksanvisning på norsk. Dette er et krav i henhold til maskinforskriften. I tillegg er det laget ett kostnadsestimat for produksjon av løfte clampet. Samt at optimal type overflatebehandling er utredet. Arbeidet som er nedlagt, gir Wellpartner svar på problemstillingen deres. Når denne oppgaven er overlevert, står Wellpartner selv fritt til å produsere utstyret og få det godkjent for løft

Widespread distribution of lymphatic vessels in human dura mater remote from sinus veins

Background and purpose: Previous experimental studies have shown that meningeal lymphatic vessels are located primarily along the walls of the dural sinus veins. Whether they are more widespread throughout human dura mater has presently not been characterized. The present study explored in humans whether meningeal lymphatic vessels may be identified remote from the sinus veins and whether they differ in the various location of dura mater.Methods: We included 15 patients who underwent neurosurgery, in whom dura mater was removed as part of the planned procedure. Tissue was prepared for immunohistochemistry using the lymphatic endothelial cell markers lymphatic vessel endothelial hyaluronan receptor 1 protein (LYVE-1), podoplanin and vascular endothelial growth factor receptor 3 (VEGFR3).Results: Lymphatic endothelial cell positive cells were found in dura mater at the posterior fossa (n = 8), temporal skull base (n = 5), frontal convexity (n = 1), and cranio-cervical junction (n = 1). They were most commonly seen remote from blood vessels, but also occurred along blood vessels, and seemed to be most abundant at the skull base.Conclusion: The present observations show that human lymphatic vessels are widespread in dura mater, not solely lining the dural sinuses

Analysis of Human Gait Using Hybrid EEG-fNIRS-Based BCI System: A Review

Human gait is a complex activity that requires high coordination between the central nervous system, the limb, and the musculoskeletal system. More research is needed to understand the latter coordination\u27s complexity in designing better and more effective rehabilitation strategies for gait disorders. Electroencephalogram (EEG) and functional near-infrared spectroscopy (fNIRS) are among the most used technologies for monitoring brain activities due to portability, non-invasiveness, and relatively low cost compared to others. Fusing EEG and fNIRS is a well-known and established methodology proven to enhance brain–computer interface (BCI) performance in terms of classification accuracy, number of control commands, and response time. Although there has been significant research exploring hybrid BCI (hBCI) involving both EEG and fNIRS for different types of tasks and human activities, human gait remains still underinvestigated. In this article, we aim to shed light on the recent development in the analysis of human gait using a hybrid EEG-fNIRS-based BCI system. The current review has followed guidelines of preferred reporting items for systematic reviews and meta-Analyses (PRISMA) during the data collection and selection phase. In this review, we put a particular focus on the commonly used signal processing and machine learning algorithms, as well as survey the potential applications of gait analysis. We distill some of the critical findings of this survey as follows. First, hardware specifications and experimental paradigms should be carefully considered because of their direct impact on the quality of gait assessment. Second, since both modalities, EEG and fNIRS, are sensitive to motion artifacts, instrumental, and physiological noises, there is a quest for more robust and sophisticated signal processing algorithms. Third, hybrid temporal and spatial features, obtained by virtue of fusing EEG and fNIRS and associated with cortical activation, can help better identify the correlation between brain activation and gait. In conclusion, hBCI (EEG + fNIRS) system is not yet much explored for the lower limb due to its complexity compared to the higher limb. Existing BCI systems for gait monitoring tend to only focus on one modality. We foresee a vast potential in adopting hBCI in gait analysis. Imminent technical breakthroughs are expected using hybrid EEG-fNIRS-based BCI for gait to control assistive devices and Monitor neuro-plasticity in neuro-rehabilitation. However, although those hybrid systems perform well in a controlled experimental environment when it comes to adopting them as a certified medical device in real-life clinical applications, there is still a long way to go

CSF circulation and dispersion yield rapid clearance from intracranial compartments

In this paper, we used a computational model to estimate the clearance of a tracer driven by the circulation of cerebrospinal fluid (CSF) produced in the choroid plexus (CP) located within the lateral ventricles. CSF was assumed to exit the subarachnoid space (SAS) via different outflow routes such as the parasagittal dura, cribriform plate, and/or meningeal lymphatics. We also modelled a reverse case where fluid was produced within the spinal canal and absorbed in the choroid plexus in line with observations on certain iNPH patients. No directional interstitial fluid flow was assumed within the brain parenchyma. Tracers were injected into the foramen magnum. The models demonstrate that convection in the subarachnoid space yields rapid clearance from both the SAS and the brain interstitial fluid and can speed up intracranial clearance from years, as would be the case for purely diffusive transport, to days.publishedVersio

Plasma neurodegeneration biomarker concentrations associate with glymphatic and meningeal lymphatic measures in neurological disorders

Clearance of neurotoxic brain proteins via cerebrospinal fluid (CSF) to blood has recently emerged to be crucial, and plasma biomarkers of neurodegeneration were newly introduced to predict neurological disease. This study examines in 106 individuals with neurological disorders associations between plasma biomarkers [40 and 42 amino acid-long amyloid-β (Aβ40 and Aβ42), total-tau, glial fibrillary acidic protein (GFAP), and neurofilament light (NfL)] and magnetic resonance imaging measures of CSF-mediated clearance from brain via extra-vascular pathways (proxy of glymphatic function) and CSF-to-blood clearance variables from pharmacokinetic modeling (proxy of meningeal lymphatic egress). We also examine how biomarkers vary during daytime and associate with subjective sleep quality. Plasma concentrations of neurodegeneration markers associate with indices of glymphatic and meningeal lymphatic functions in individual- and disease-specific manners, vary during daytime, but are unaffected by sleep quality. The results suggest that plasma concentrations of neurodegeneration biomarkers associate with measures of glymphatic and meningeal lymphatic function

Surgical treatment of symptomatic pineal cysts without hydrocephalus-meta-analysis of the published literature

Background To examine published data and assess evidence relating to safety and efficacy of surgical management of symptomatic pineal cysts without hydrocephalus (nhSPC), we performed a systematic review of the literature and meta-analysis. Methods Following the PRISMA guidelines, we searched Pubmed and SCOPUS for all reports with the query 'Pineal Cyst' AND 'Surgery' as of March 2021, without constraints on study design, publication year or status (PROSPERO_CRD:42,021,242,517). Assessment of 1537 hits identified 26 reports that met inclusion and exclusion criteria. Results All 26 input studies were either case reports or single-centre retrospective cohorts. The majority of outcome data were derived from routine physician-recorded notes. A total of 294 patients with surgically managed nhSPC were identified. Demographics: Mean age was 29 (range: 4-63) with 77% females. Mean cyst size was 15 mm (5-35). Supracerebellar-infratentorial approach was adopted in 90% of cases, occipital-transtentorial in 9%, and was not reported in 1%. Most patients were managed by cyst resection (96%), and the remainder by fenestration. Mean post-operative follow-up was 35 months (0-228). Presentation: Headache was the commonest symptom (87%), followed by visual (54%), nausea/vomit (34%) and vertigo/dizziness (31%). Other symptoms included focal neurology (25%), sleep disturbance (17%), cognitive impairment (16%), loss of consciousness (11%), gait disturbance (11%), fatigue (10%), 'psychiatric' (2%) and seizures (1%). Mean number of symptoms reported at presentation was 3 (0-9). Outcomes: Improvement rate was 93% (to minimise reporting bias only consecutive cases from cohort studies were considered, N= 280) and was independent of presentation. Predictors of better outcomes were large cyst size (OR= 5.76; 95% CI: 1.74-19.02) and resection over fenestration (OR= 12.64; 3.07-52.01). Age predicted worse outcomes (OR= 0.95; 0.91-0.99). Overall complication rate was 17% and this was independent of any patient characteristics. Complications with long-term consequences occurred in 10 cases (3.6%): visual disturbance (3), chronic incisional pain (2), sensory disturbance (1), fatigue (1), cervicalgia (1), cerebellar stroke (1) and mortality due to myocardial infarction (1). Conclusions Although the results support the role of surgery in the management of nhSPCs, they have to be interpreted with a great deal of caution as the current evidence is limited, consisting only of case reports and retrospective surgical series. Inherent to such studies are inhomogeneity and incompleteness of data, selection bias and bias related to assessment of outcome carried out by the treating surgeon in the majority of cases. Prospective studies with patient-reported and objective outcome assessment are needed to provide higher level of evidence.Peer reviewe

OXR1A, a Coactivator of PRMT5 Regulating Histone Arginine Methylation

Oxidation resistance gene 1 (OXR1) protects cells against oxidative stress. We find that male mice with brain-specific isoform A knockout (Oxr1A−/−) develop fatty liver. RNA sequencing of male Oxr1A−/− liver indicates decreased growth hormone (GH) signaling, which is known to affect liver metabolism. Indeed, Gh expression is reduced in male mice Oxr1A−/− pituitary gland and in rat Oxr1A−/− pituitary adenoma cell-line GH3. Oxr1A−/− male mice show reduced fasting-blood GH levels. Pull-down and proximity ligation assays reveal that OXR1A is associated with arginine methyl transferase PRMT5. OXR1A-depleted GH3 cells show reduced symmetrical dimethylation of histone H3 arginine 2 (H3R2me2s), a product of PRMT5 catalyzed methylation, and chromatin immunoprecipitation (ChIP) of H3R2me2s shows reduced Gh promoter enrichment. Finally, we demonstrate with purified proteins that OXR1A stimulates PRMT5/MEP50-catalyzed H3R2me2s. Our data suggest that OXR1A is a coactivator of PRMT5, regulating histone arginine methylation and thereby GH production within the pituitary gland.publishedVersio

Copy number loss in SFMBT1 is common among Finnish and Norwegian patients with iNPH

Objective To evaluate the role of the copy number loss in SFMBT1 in a Caucasian population. Methods Five hundred sixty-seven Finnish and 377 Norwegian patients with idiopathic normal pressure hydrocephalus (iNPH) were genotyped and compared with 508 Finnish elderly, neurologically healthy controls. The copy number loss in intron 2 of SFMBT1 was determined using quantitative PCR. Results The copy number loss in intron 2 of SFMBT1 was detected in 10% of Finnish (odds ratio [OR] = 1.9, p = 0.0078) and in 21% of Norwegian (OR = 4.7, p <0.0001) patients with iNPH compared with 5.4% in Finnish controls. No copy number gains in SFMBT1 were detected in patients with iNPH or healthy controls. The carrier status did not provide any prognostic value for the effect of shunt surgery in either population. Moreover, no difference was detected in the prevalence of hypertension or T2DM between SFMBT1 copy number loss carriers and noncarriers. Conclusions This is the largest and the first multinational study reporting the increased prevalence of the copy number loss in intron 2 of SFMBT1 among patients with iNPH, providing further evidence of its role in iNPH. The pathogenic role still remains unclear, requiring further study.Peer reviewe