Calibration and characterization of the ELVIS hydrophones

Calibration is an important _eld and is used everywhere from education, research and industry. Every electrical equipment has to be calibrated during manufacturing and even over time as it is worn down. The purpose of calibration is to come as close as possible to the true value. The question is how close is close enough and how close is possible? Because even the equipment used for calibration needs calibrating, which in turn also needs calibrating and so on. This thesis will be about the hydrophones used by the system ELVIS. The method of choice is calibration by comparison. Its idea is to compare the signal received by the uncalibrated transducer with the same signal received by an already calibrated one. This might seem trivial but there are many things to be considered. ELVIS uses 47 hydrophones. The frequency range subjected to calibration is 30-250 kHz which leads to a huge amount of data to be recorded, analysed and presented. The result shows that each individual hydrophone performs similar to each other. Because of the insecurities regarding the reference hydrophone, no absolute measurements will be presented

Cancer resistance in the naked mole-rat (Heterocephalus glaber)

Nakenråttan (Heterocephalus glaber) är ett däggdjur som lever hela sitt liv under jord i eusociala kolonier i östra Afrika. Den är jordens mest långlivade gnagare med en maximal livslängd på över 30 år, vilket är häpnadsväckande i jämförelse med 4 år hos en mus i samma storlek. Den nakna gnagaren har, utöver sin avsaknad av päls, en bristande förmåga till termoreglering. Med en kroppstemperatur på omkring 30–32°C och en mycket värmestabil livsmiljö, får den problem med termoregleringen redan när temperaturen i omgivningen börjar närma sig 15°C och nakenråttan liknar i just det avseendet mer en ödla än ett typiskt däggdjur. Nakenråttan är dock anmärkningsvärd i många andra avseenden. Den klarar upp till 18 minuter av anoxi, den är väldigt smärttålig och under de första cirka 75% av livet verkar den inte åldras överhuvudtaget; den är mycket motståndskraftig mot många av de vanligaste tecknen på åldrande och åldersrelaterade sjukdomarna. De är även fertila upp i hög ålder och uppvisar en ovanligt låg grad av gendifferentiering de första 20 åren av sina liv. Största fokus i denna litteraturstudie ligger på nakenråttans resistens mot cancer. Innan februari 2016 fanns inga dokumenterade fall av tumörutveckling hos nakenråttor, trots att djuren forskats på och observerats extensivt i många år. Forskningen har kommit fram till ett antal olika skäl till nakenråttans cancerresistens. I denna litteraturstudie nämns bland annat dess höga produktion kombinerat med låg nedbrytning av den extracellulära stödjemolekylen hyaluron, en molekyl som dessutom är 5 gånger så stor hos nakenråttan som hos mus. Nakenråttan har även uppvisat höga nivåer av a2-makroglobulin och ett antal integriner inblandade i celladhesion; något som påverkar såväl migration och adhesion som invasion hos både normala celler och cancerceller. Fibroblasterna hos nakenråttan är betydligt mer resistenta mot många toxiner än vad musens är. Det har dessutom visat sig att de vid exponering av gentoxiner kan gå in i temporär vilofas och därmed undvika att föra vidare skadat DNA. Denna förmåga hade inte mössens fibroblaster i försöket. Nakenråttan uppvisar dessutom basala nivåer av p53 som är 50 gånger större än de hos mus. Under gentoxisk exponering ökar nivåerna dessutom betydligt mer än vad musens gör. Detta betyder att de förmodligen har ett bättre skydd mot cancer på cellnivå, då p53 reglerar till exempel vilofas och apoptos. Även av Nrf2 (nuclear factor erythroid 2-related factor), ett protein inblandat i cellens antioxidativa skydd, har nakenråttan uppvisat höga nivåer. Nrf2 har visats vara inblandat i kroppens skydd mot en rad sjukdomar, bland annat cancer. De höga nivåerna av Nrf2 kan även vara en förklaring till nakenråttans resistens mot toxiner. Om man vill använda sig av nakenråttans mekanismer mot åldrande och tumörutveckling i framtida forskning, så finns där ingen brist på underlag för det. Mekanismerna är många och samverkar i många fall med varandra, vilket gör det hela något komplext. Men det finns ingen tvekan om att nakenråttans fysiologi kan vara till stor hjälp för framtida forskning, och kanske kan den en dag bidra till ett längre och friskare liv för såväl oss människor som för våra husdjur.The naked mole-rat (Heterocephalus glaber) is a fascinating eusocial, subterranean mammal living in East Africa. The world’s longest living rodent has a maximum life span of over 30 years. A remarkable number when compared to a mouse of similar size, with a maximum life span of about 4 years. The naked mole-rat, in addition to its lack of fur, has a poor thermoregulatory capacity. In fact, with a body temperature of around 30–32°C and an extremely thermostable habitat, it has difficulty managing thermoregulation even at temperatures approaching 15°C. In that regard, this rodent more closely resembles a reptile than a typical mammal. Even so, the naked mole-rat is remarkable in various other aspects. They can sustain up to 18 minutes of anoxia and they are extraordinarily resistant to pain. They also do not seem to age at all during at least the first 75% of their lives, being unusually resistant to most common signs of aging and age-related diseases. Naked mole-rats remain fertile for most of their lives and during their first 20 years they show very little sign of gene differentiation. The main focus of this literature study is on the resistance to cancer in the naked mole-rat. Prior to February of 2016 there were no reported cases of tumors in naked mole-rats, despite the fact that they had been extensively studied for many years. Researchers have discovered several causes for cancer resistance in the naked mole-rat. This literature study mentions the extracellular molecule hyaluronan, which is about 5 times bigger in this animal than it is in the mouse. The naked mole-rat has also been shown to have higher levels of both a2-makroglobulin and a number of integrins involved in cell adhesion; something which has an impact on the migration, adhesion and even invasion of both regular cells as well as cancer cells. Naked molerat fibroblasts have a very high tolerance to several toxins compared to the fibroblasts of mice. In addition, when exposed to genotoxins the fibroblasts of naked mole-rats have been shown to enter temporary senescence until any DNA damage is repaired, an ability that mouse fibroblasts lacked. The base levels of p53 have been found to be 50 times higher in naked mole-rats than in mice. Furthermore, these base levels of p53 exhibit a considerably larger increase during exposure to genotoxins than do the ones in mice, implying a more elaborate cellular protection against tumor development. In these experiments, researchers also found higher levels of the protein Nrf2 (nuclear factor erythroid 2-related factor) in the naked mole-rat. Nrf2 has a proven part in the defense against many common diseases including cancer. The high levels of Nrf2 may also provide an explanation to the apparent tolerance to various toxins in these animals. For anyone who wishes to do further research in the fields of longevity and cancer on the naked mole-rat, pre-conditions are great. There is a ton of material on its remarkable physiology, including its longevity and cancer resistance. There are numerous underlying mechanisms to these qualities in the naked mole-rat, of which many seem to be cooperating; making it all a bit complex. However, the possibilities of this animal being of great importance in future scientific research are undeniable. And perhaps one day the naked mole-rat may contribute to a longer and healthier life for us humans as well as for our pets

The combination of high sensitivity troponin T and copeptin facilitates early rule-out of ACS: a prospective observational study

BACKGROUND: The combination of the new high sensitivity troponin T (hsTnT) assays and copeptin, a biomarker of endogenous stress, has been suggested to have the potential of early rule-out of acute coronary syndrome (ACS). The aim of this study was to examine the ability of this combination to rule out ACS in patients presenting with chest pain and to compare the diagnostic performance to hsTnT alone. METHOD: In this prospective observational study, patients with chest pain admitted for observation were consecutively included. Patients presenting with ST elevation were excluded. Copeptin and hsTnT were analyzed at admission and hsTnT was thereafter determined approximately every 3(rd) hour as long as clinically indicated. The follow-up period was 60 days. A combined primary endpoint of ACS, non-elective percutanous coronary intervention, non-elective coronary artery bypass surgery and death of all causes was used. RESULTS: 478 patients were included. 107 (22%) patients were diagnosed with ACS during hospital stay. 70 (14%) had non-ST-segment elevation myocardial infarction (NSTEMI) and 37 (8%) had unstable angina pectoris (UAP). The combination of hsTnT >14 ng/L or copeptin ≥14 pmol/L at admission identified ACS with a higher sensitivity than hsTnT alone: 0.83 (95% confidence interval (CI): 0.74-0.89) versus 0.69 (95% CI: 0.59-0.77), p <0.001. Negative predictive values (NPV) 91% (95% CI: 86-94) versus 89% (95% CI: 84-92). A repeated hsTnT analyzed 3-4 hours after admission resulted in a sensitivity of: 0.77 (95% CI: 0.65-0.86), p =0.031 for comparison with the combination analyzed at admission. CONCLUSIONS: In patients presenting with chest pain admitted for observation, the combination of hsTnT and copeptin analyzed at admission had a significantly higher sensitivity to diagnose ACS than hsTnT alone. We report a sensitivity of 83% and a NPV of 91% for the combination of hsTnT and copeptin and we conclude that biomarkers alone are not sufficient to rule out ACS. However, the combination of hsTnT and copeptin seems to have a significantly higher sensitivity to identify ACS than a repeated hsTnT test, and thus enables an earlier risk stratification of chest pain patients. This can be time-saving and beneficial for the individual patient by contributing to early decisions on treatment, need of further assessment and level of care

Terroireffekt i teori och praxis

Under senare år har det etablerats ett flertal kommersiella vinodlingar runt om i Sverige och viner från dessa finns nu till försäljning genom Systembolaget. En debatt har uppstått kring Sveriges potential för att tillverka vin, hur dessa viner ter sig rent kvalitetsmässigt och huruvida de är något att ta notis om, annat än som kuriosa för vinentusiaster. I länder med längre tradition av vinodling förekommer begreppet ”terroireffekt” frekvent i samband med viners kvalitet och typicitet. Detta arbete syftar till att klargöra innebörden av begreppet ”terroir”, samt hur några av företagsledarna till större svenska vinodlingsföretag uppfattar och värderar denna teori. Detta har gjorts genom en litteraturstudie inriktad på aktuell forskning inom ämnet och genom en enkät – och intervjustudie riktad mot tre svenska vinodlare. Resultatet av detta arbete visar att: • det inte råder konsensus kring begreppets innebörd, men att det finns några tydliga huvudströmningar. • de svenska vinodlarna som deltagit i studien i hög grad är av samma åsikter gällande uppfattning av begreppet terroireffekt. Deras värdering av begreppet varierar dock.In recent years, a number of commercial vineyards and vineries have been established in Sweden and the wines of these are now on sale. A debate has arisen around Sweden’s potential to produce wine from grapes grown in Sweden and the quality of these wines. Are they something to be considered, or do they rather display a curiosity for wine enthusiasts. In countries with a longer tradition of winemaking and -marketing the term “terroir” is frequently associated with wines of quality and typicality. This work aims to clarify the meaning of “terroir” as a concept and how some leaders of large Swedish vineyards and vineries perceive and assess this concept. This has been done through a literature review focused on current research on the subject and through a questionnaire –and interview study targeting three Swedish winemakers. The result of this study shows that: • there is no basic consensus on the term “terroir”, but that there are several well-established theories. • the Swedish growers who participated in the study largely perceive the term “terroir” in similar ways, but they validate it differently

The balance of serum matrix metalloproteinase-8 and its tissue inhibitor in acute coronary syndrome and its recurrence

Background: Matrix metalloproteinase-8 (MMP-8) is involved in the breakdown of the extracellular matrix increasing the vulnerability of atherosclerotic lesions. We analysed the diagnostic value of serum MMP-8 and tissue inhibitor of metalloproteinase-1 (TIMP-1) concentrations in acute coronary syndrome (ACS) and their prognostic value in ACS recurrence. Methods: The population comprised 343 patients with ACS [including 108 unstable angina pectoris and 235 acute myocardial infarctions (AMI)] and 326 healthy controls. Additionally, 157 (45.8%) patients were resampled during the recovery. The ACS patients were followed up for 6 years. Results: MMP-8, TIMP-1, and their molar ratio distinguished the cases from the controls; C-statistic of the multivariate model (95% CI, p-value) including the MMP-8/TIMP-1 ratio regarding its discriminating ability for AMI was 0.922 (0.893-0.950, p < 0.001). After the acute phase of ACS, median MMP-8 and TIMP-1 concentrations decreased (p < 0.001) by 34.5 and 28.7%, respectively, but ended up on a different level than those found in the controls. In the follow-up, acute phase and recovery period TIMP-1 concentrations associated with cardiovascular death with hazard ratios 4.31 (2.00-9.26, p < 0.001) and 4.69 (1.10-20.01, p = 0.037), respectively. Conclusions: The increase of serum MMP-8 and TIMP-1 concentrations may reflect plaque instability and tissue damage. TIMP-1 concentrations are associated with poor outcome in patients with ACS. The findings may have practical implications in both diagnostics and therapeutics. (c) 2011 Elsevier Ireland Ltd. All rights reserved

De gotländska eldsjälarna

Trots att det sker en utflytt från icke tätortsnära landsbygd i landet bedrivs ändå en framgångsrik landsbygdsutveckling på Gotland. Detta i form av tio lokala utvecklingsbolag där privatpersoner och företag kan köpa aktier i syfte att främja den lokala bygden. Bakom bolagen står ideellt arbetande personer som lägger ner mycket kraft och hundratals arbetstimmar för att driva igenom projekt som skapar samhällsnytta i bygden. Dessa personer skulle i daglig benämning kunna gå under begreppet eldsjäl, men det saknas idag både svensk och internationell forskning inom ämnet. Även om vissa karaktärsdrag kan jämföras med både samhällsentreprenörskap, landsbygdsentreprenörskap och entreprenörskap på landsbygden finns ingen tydlig beskrivning av begreppet. Syftet med denna uppsats är därför att inom ramen för forskningsprogrammet Nycklar till en levande landsbygd, beskriva begreppet eldsjäl samt försöka förstå eldsjälens roll för Gotlands landsbygd. Detta görs genom en kvalitativ studie där fyra eldsjälar deltagit i semistrukturerade intervjuer för att kartlägga gemensamma egenskaper samt relationen till social, rumslig och institutionell kontext. Uppsatsen diskuterar därför utifrån de teoretiska ramarna av samhällsentreprenörskap och kontext vilka karaktärsdrag och egenskaper en eldsjäl präglas av, samt vad som driver individerna att trots stort motstånd fortsätta sitt arbete utan krav på att få någonting i gengäld. Studien visar därmed att eldsjälar är starkt beroende av sociala nätverk, samt arbetar oegoistiskt för att skapa samhällsnytta där drivkraften är en positiv förändring i bygden de bor och verkar i. För att bibehålla denna motivation krävs dock någon form av bekräftelse eller återkoppling på arbetet. Eldsjälar spelar en betydande roll i utvecklingen av Gotlands landsbygd, och tar vid där Region Gotland inte längre räcker till. Eldsjälarna skapar trevnad i bygden för att fler ska stanna kvar eller flytta dit.Urbanisation is characterizing Swedish rural areas, yet successful rural development is spread over Gotland. There rural development is partly run by local development corporations, where both individuals and firms are able to invest in stocks to improve the local district. Behind these corporations stand individuals who invest a large amount of their time and effort, without gaining profit or even encouragements. In Swedish terms those people often are called eldsjäl or in English driving spirit, but there seems to be a loss i published theory about the subject. Even though societal entrepreneurship, rural entrepreneurship and entrepreneurship in rural all contain characteristics reminding of a driving spirit, there is no clear definition of a driving spirit as a concept. Within the the research programme Nycklar till en levande landsbygd the aim is to, with a qualitative approach, describe the concept of a driving spirit and its relation to context. This paper therefore discuss a driving spirit’s qualities as well as key factors to continue with their plan in spite of great opposition. The study thereby show that social context is of great importance in order to create societal value, which is in their main interest. Driving spirits are however in need of encouragement or feedback in order to keep a continuance in their work. Driving spirits continue where administrative authorities are insufficient and are therefore important for rural development in Gotland

Att odla eller inte odla : en studie om lantbrukares resurser och deras beslut att odla åkerböna

Climate change and sustainability is discussed all over the world. In Sweden, as well as in many other countries worldwide, the food and agricultural system is one of the most important industries. It is both affected by and affecting climate change. Modern agricultural production relies on an increasingly higher use of resources and inputs to maintain a high production level of animal feed and human food. Expansion of legumes could improve resource efficiency and promote diversification of cropping systems which leads to a more sustainable agriculture. Despite all of the potential and benefits of growing more legumes, less than 2 % of the acreage in Sweden was used for legume production in 2018. Broad bean is one of the legumes that can be grown in large parts of Sweden and would be relatively easy to start growing. This study aims to find differences and similarities among farmers who do and do not grow broad beans, to understand what the most determining resources are and how farmers use those resources to make decisions regarding crop planning. A mixed method approach is used in order to gain a deeper understanding through use of qualitative data, and quantitative data to conduct measurements. The data is collected through telephone-interviews with farmers in four counties in Sweden (Uppsala, Västmanland, Östergötland and Västra Götaland). The collected data is analyzed by both a qualitative thematic analysis and a quantitative statistical analysis to test several developed hypotheses. The study concludes that the decision of crop is intimately linked to the business and the farmers’ allocation of recourses. Mainly, the physical resources determine whether the farmer grow broad beans or not. Human resources also influence the decision making of farmers but do not heavily affect the specific decision to grow broad bean or not. In our study farmers’ perception of the broad bean differ. Farmers who grow broad bean view them as an opportunity, while farmers who do not grow broad bean see it as a risk. Broad bean farmers are also more strategic and think in long-term perspective when planning their crop sequence. While the farmers who do not grow broad beans are more flexible and adaptable to changing prerequisites and circumstances. Uncertainty regarding an innovation is an obstacle for adoption. To reach a goal of growing more broad beans in the future, development of new varieties and delivery options could be a way to overcome this uncertainty and make it more suitable and attractive to adopt in to cropping systems.Klimatförändringar och hållbarhet diskuteras över hela världen. I Sverige, liksom i många andra länder över hela världen, anses livsmedels- och jordbruksindustrin vara en av de viktigaste industrierna, som både påverkar och påverkas av klimatet. Modern jordbruksproduktion bygger på en ökad och högre användning av resurser och insatser för att upprätthålla en hög produktionsnivå för djurfoder och humankonsumtion. Expansionen av mer baljväxter i odlingen kan leda till bättre resurseffektivitet och medföra diversifiering av växtodlingen, vilket kan leda till ett mer hållbart jordbruk. Trots alla möjligheter och fördelar med att odla baljväxter utgörs mindre än 2 % av odlingsarealen i Sverige utav baljväxter. Åkerböna är en baljväxtgröda som kan odlas i större delen av Sverige, är relativt enkel att odla samt kräver inga specialmaskiner. Denna studie syftar till att finna skillnader och likheter mellan lantbrukare som odlar och inte odlar åkerböna, för att förstå vilka som är de mest avgörande resurserna och hur lantbrukare använder dessa för att fatta beslut i sitt företagande. En kombination av kvalitativ och kvantitativ metod används för att göra det möjligt att både statistiskt jämföra och få en djupare förståelse av det empiriska materialet. Det empiriska materialet har samlats in via telefonintervjuer med lantbrukare i fyra län i Sverige (Uppsala län, Västmanlands län, Östergötlands län och Västra Götalands län). Den insamlade data har sedan analyseras genom både en kvalitativ tematisk analys och en kvantitativ statistisk analys för att testa ett antal hypoteser. Studien visar att beslutsfattandet gällande val av gröda är nära kopplat till lantbrukarnas företagande och allokering av resurser. I huvudsak avgör de fysiska resurserna om lantbrukaren har förmåga att odla åkerböna eller inte. De humana resurserna påverkar också beslutsfattandet i allmänhet, men påverkar i hög grad inte beslutet att odla åkerböna eller inte. I vår studie skiljer sig lantbrukarnas uppfattning om åkerbönan som potential gröda. De lantbrukare som odlar åkerböna ser grödan som en möjlighet, medan de som inte odlar ser grödan som en risk. Lantbrukare som odlar åkerböna är mer strategiska och tänker långsiktigt när de planerar sin växtodling, medan lantbrukare som inte odlar åkerböna är mer flexibla och anpassningsbara till föränderliga förutsättningar och omständigheter. Osäkerhet för en innovation kan vara ett hinder för att implementera den i sitt företagande. För att nå ett mål om att odla mer åkerbönor i framtiden kan utvecklingen av nya sorter och leveransalternativ vara ett sätt att övervinna denna osäkerhet och göra åkerbönan mer lämpad och attraktiv att odla

Resistance to aspirin is increased by ST-elevation myocardial infarction and correlates with adenosine diphosphate levels

BACKGROUND: To be fully activated platelets are dependent on two positive feedback loops; the formation of thromboxane A(2 )by cyclooxygenase in the platelets and the release of ADP. We wanted to evaluate the effect of aspirin on platelet function in patients with acute coronary syndromes and we hypothesized that increased levels of ADP in patients with acute coronary syndromes could contribute to aspirin resistance. METHODS: Platelet activity in 135 patients admitted for chest pain was assessed with PFA-100. An epinephrine-collagen cartridge (EPI-COLL) was used for the detection of aspirin resistance together with an ADP-collagen cartridge (ADP-COLL). ADP was measured with hplc from antecubital vein samples. Three subgroups were compared: chest pain with no sign of cardiac disease (NCD), NonST-elevation myocardial infarction (NSTEMI) and STEMI. RESULTS: Platelet activation was increased for the STEMI group compared NCD. Aspirin resistance defined as <193 sec in EPI-COLL was 9.7 % in NCD, and increased to 26.0 % (n.s.) in NSTEMI and 83.3 % (p < 0.001) in STEMI. Chronic aspirin treatment significantly reduced platelet aggregation in NCD and NSTEMI, but it had no effect in STEMI. Plasma levels of ADP were markedly increased in STEMI (905 ± 721 nmol/l, p < 0.01), but not in NSTEMI (317 ± 245), compared to NCD (334 ± 271, mean ± SD). ADP levels correlated with increased platelet activity measured with ADP-COLL (r = -0.30, p < 0.05). Aspirin resistant patients (EPI-COLL < 193 sec) had higher ADP levels compared to aspirin responders (734 ± 807 vs. 282 ± 187 nmol/l, mean ± SD, p < 0.05). CONCLUSION: Platelets are activated and aspirin resistance is more frequent in STEMI, probably due to a general activation of platelets. ADP levels are increased in STEMI and correlates with platelet activation. Increased levels of ADP could be one reason for increased platelet activity and aspirin resistance

Infarct evolution in man studied in patients with first-time coronary occlusion in comparison to different species - implications for assessment of myocardial salvage

<p>Abstract</p> <p>Background</p> <p>The time course of infarct evolution, i.e. how fast myocardial infarction (MI) develops during coronary artery occlusion, is well known for several species, whereas no direct evidence exists on the evolution of MI size normalized to myocardium at risk (MaR) in man. Despite the lack of direct evidence, current literature often refers to the "golden hour" as the time during which myocardial salvage can be accomplished by reperfusion therapy. Therefore, the aim of the present study was to investigate how duration of myocardial ischemia affects infarct evolution in man in relation to previous animal data. Consecutive patients with clinical signs of acute myocardial ischemia were screened and considered for enrollment. Particular care was taken to assure uniformity of the patients enrolled with regard to old MI, success of revascularization, collateral flow, release of biochemical markers prior to intervention etc. Sixteen patients were ultimately included in the study. Myocardium at risk was assessed acutely by acute Myocardial Perfusion Single photon emission computed tomography (MPS) and by T2 imaging (T2-STIR) cardiovascular magnetic resonance (CMR) after one week in 10 of the 16 patients. Infarct size was measured by late gadolinium enhancement (LGE) at one week.</p> <p>Results</p> <p>The time to reach 50% MI of the MaR (T₅₀) was significantly shorter in pigs (37 min), rats (41 min) and dogs (181 min) compared to humans (288 min). There was no significant difference in T₅₀when using MPS compared to T2-STIR (p = 0.53) for assessment of MaR (288 ± 23 min vs 310 ± 22 min, T₅₀± standard error). The transmural extent of MI increased progressively as the duration of ischemia increased (R²= 0.56, p < 0.001).</p> <p>Conclusion</p> <p>This is the first study to provide direct evidence of the time course of acute myocardial infarct evolution in relation to MaR in man with first-time MI. Infarct evolution in man is significantly slower than in pigs, rats and dogs. Furthermore, infarct evolution assessments in man are similar when using MPS acutely and T2-STIR one week later for determination of MaR, which significantly facilitates future clinical trials of cardioprotective therapies in acute coronary syndrome by the use of CMR.</p