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Två flugarter: mer alkohol, mer sex? Artbildning är en av de viktigaste processerna inom evolutionsbiologi. För att en art ska bli två krävs det att arten formar två grupper som inte reproducerar sig med varandra. Om en sådan reproduktiv isolering, som det kan kallas, fortgår i flera generation kan så pass många genetiska skillnader åsamlas mellan grupperna att hybrider (avkommor från två olika tSexually reproducing species tend to have reproductive barriers between them that prevent hybrid offspring from being formed. Drosophila melanogaster and D. simulans are two closely related species that can form sterile hybrids. In addition to their post-zygotic barriers, which cause the hybrid sterility, some behavioral pre-zygotic barriers also exist. These include different preferences for cour

Rare divergent RNAs in disease In human cells, genes are transcribed into an RNA before being translated into a protein, but first its structure under strict regulation undergoes changes called RNA splicing. Premature RNAs are organized in exon and intron units, where the latter are removed, to join exons together in the mature RNA. However, a variation of exon/intron combination can occur via a

Praematurum – mutanterna som snabbar på blomningen i korn Hordeum vulgare (känt som ”korn” i vardagligt språk) är idag världens fjärde mest odlade sädesslag och används framför allt som djurfoder och till ölbryggning. På grund av den globalt ökande populationen och ett nyligen återfunnet intresse i nationell självförsörjning så blir vikten av forskning inom växtförädling bara större och större. EWhen cultivating barley (Hordeum vulgare), access to cultivars with shorter flowering time can be helpful in various agricultural settings, such as the effort of expanding agricultural capabilities into colder regions with shorter growing seasons. The recently identified gene Praematurum-b (Mat-b) is known to cause the plants to flower 7 days early on average. This thesis aimed to analyze the effe

Evolutionen som livboj för en krympande slända Många organismer påverkas negativt av mänsklig miljöpåverkan, och riskerar att dö ut. Evolutionära processer kan dock fungera som en livboj och bromsa den negativa utvecklingen från miljöförändringar. Global uppvärmning driver en insektsart till en mindre kroppsstorlek. Men när naturlig selektion istället verkar för en stor kroppsstorlek kommer de neDue to human-induced environmental changes, many natural populations are undergoing extensive fitness declines. Natural or sexual selection could potentially shift the phenotypic mean of critical traits towards new phenotypic optima, promoting evolutionary rescue. However, this process has rarely been studied in natural populations. Furthermore, the population fitness can also be increased by gene

Spinosad: en pollinatörs mardröm Bekämpningsmedel är vanliga i jordbruket för att säkra skördar, men kan ha negativa effekter på nyttiga insekter. Spinosad, ett biologiskt bekämpningsmedel framställt ur bakterier och godkänt inom ekologiskt jordbruk i EU, angriper insekters nervsystem och orsakar muskelsammandragningar, förlamning och död. Mitt experiment visar att spinosad i fältrealistiska koncThe extensive use of pesticides within the agricultural landscape is essential for maintaining sufficient yields and sustaining our growing population, however, their widespread use is not without costs. Increasing evidence shows that pesticides harm many non-target organisms, including those providing vital ecosystem services. Pollinators, for instance, are critical for the fruiting of nearly 75%

Background: A Swedish version of the Patient-Rated Ulnar Nerve Evaluation (PRUNE-S), a patient-reported outcome measure for ulnar nerve entrapment, was created, according to cross-cultural adaptation guidelines, and reliability, validity, and responsiveness were evaluated. Methods: In total, 43 patients (mean [SD] age, 49 [16] y; 54% men) were consecutively examined, including the PRUNE-S (retest:

The development of EU labour and social law has been described as a pendulum in the sense of focus shifting between economic interests, such as competitiveness for industry, and social interests, such as improving working and living conditions. This view is to a large extent based on the presumption that those interests are contrasting and pursuing one of them would necessarily exclude the promoti

Neurodegenerative diseases (NDs), such as Alzheimer’s disease (AD), Parkinson’s disease (PD) and frontotemporal dementia (FTD), exhibit distinct yet overlapping pathological mechanisms. Leveraging large-scale plasma proteomics data from the Global Neurodegeneration Proteomics Consortium, we analyzed 10,527 plasma samples (1,936 AD, 525 PD, 163 FTD, 1,638 dementia and 6,265 controls) to identify di

In historical the Netherlands, child mortality was distributed unequally between families and this inequality persisted across generations. Using family reconstitution data for the province of Zeeland (LINKS) containing over 200,000 children born 1835–1914, I show that mortality was higher among children under age 5 whose parents lost siblings under age 5. Intergenerational persistence was stronge

Background Olfactory dysfunction is a common non-motor symptom in Parkinson’s disease (PD). The objective was to evaluate the association between olfaction in PD with cross-sectional and longitudinal assessments of clinical variables and novel cerebrospinal fluid (CSF) markers. Methods Patients with PD and baseline olfactory function assessed using the Brief Smell Identification Test (B-SIT) were

Cytolysin A (ClyA) is a pore-forming protein from a strongly silenced gene in non-pathogenic Escherichia coli, including typical commensal isolates in the intestinal microbiome of healthy mammalian hosts. Upon overproduction, ClyA-expressing bacteria display a cytolytic phenotype. However, it remains unclear whether sublytic amounts of native ClyA play a role in commensal E. coli-host interactions

This school meals case study forms part of a collection led by the Research Consortium for School Health and Nutrition’s "Good Examples" Community of Practice. The School Meals Case Study of Sweden serves to document how the national school meals programme is organized, funded, and monitored throughout the country. The objectives of this case study include presenting an introduction to the country

Flugan, bakterien och valet mellan tistlarna Mångfalden av liv på jorden formas av samspelet mellan arter och deras miljöer. Ett av de allra äldsta samspelen är det man finner mellan insekter och bakterier, där de ofta lever tillsammans i symbios. I släktet Tephritis (Diptera: Tephritidae, borrflugor) finns just en sådan symbios med bakterien Candidatus Stammerula tephritidis (Stammerula). Genet

Path integration is a navigational strategy that allows animals to return home in a straight line after an outbound journey, by integrating the distance and direction traveled. With their accessible brains, insects are the perfect model organisms to study this target-directed behavior at the neural level. The Central Complex (CX) is a group of neural structures (neuropils) in the insect brain suit