Distributional movements of subpopulations may act as a buffer to prevent the loss of a species in a certain area. However, within subpopulations adaptations may evolve that makes the inhabitants of a certain habitat to better cope with prevailing environmental conditions. If such traits are related to reproduction, they may reduce the opportunity of gene exchange between other subpopulations. Also, a lack of adaptations to a specific habitat may be what prevents a group of individuals, arriving from an adjacent habitat, to successfully colonize an area where a previous subpopulation has been lost.This is the report from a field study conducted in the wetland Lake Långsjön, that in 2018 was restored in order to promote the recruitment of anadromous pike (Esox lucius) to the Baltic Sea. Commonly, wetlands that are restored to promote anadromous pike recruitment, are constructed so that they enable spawning migration from the sea towards the wetland and juvenile emigration towards the sea only. In that sense Lake Långsjön is different, from other wetlands restored for the same purpose, due to that it is connected to both the Baltic Sea and an upstream located freshwater lake. By quantifying the migration of pike (spawners and juveniles) in both directions I explore the consequences that the regained connectivity between the Lake Långsjön and the coast may have on the population dynamics within this wetland; (i) whether it is potentially influenced by allowing mixture between pike with different migratory strategies for spawning (anadromous and potamodromous), (ii) what drivers there are of pike fry emigration and how they may influence the pike fry emigration route and (iii) whether or not the pike of potamodromous origin, resident in the upstream located lake, may work as a source, providing the Baltic Sea with pike juveniles. Pike spawners arriving in the wetland were caught in traps between March - April. Pike fry were caught withing the wetland with fyke nets and by netting. Emigrating pike fry were caught in fyke nets. Findings suggest that spawning migration patterns do not differ between anadromous and potamodromous pike. However, the spawners arriving from the Baltic Sea I suggested are to be composed by offspring of potamodromous origin, possibly hatched during the previous season, and that they as juveniles swam downstream. This, in turn, indicates that the potamodromous stock can help establish an anadromous stock in the Baltic Sea. Still, due to the observation of pike fry displaying an emigration behaviour upstream, origin is identified as a factor that may influence the pike fry emigration route. Also, this emigration pattern seems to indicate a heritable trait that has not been described before among pike, that of downstream spawning. The restoration of the wetland and the regained connectivity is key, both for the ability to restock the Baltic Sea with pike juveniles but also to ensure the conservation of a fascinating stock of pike exhibiting a unique spawning strategy

Opening migratory pathways is crucial for the brown trout´s ability to recolonize spawning- and rearing areas, in order to complete its lifecycle. Damming rivers for hydropower production has created obstacles for migration, and nature-like fishways are one measure used to recreate connectivity. The purpose of this bachelor´s thesis was to find out how the nature-like fishway, constructed in 2016, at Billsta power plant, central Sweden, was used by migratory brown trout for upstream and downstream passage, and to observe if the migration pattern changed over time, between 2018-2020. The collected data comes from an automatic fish-counter that has been located upstream of the nature-like fishway. To analyze the data, recorded trout were categorized into two length classes, spawning-size and smolt-size, according to criteria from the Swedish Agency for Marine and Water Management (HaV). Since individual fish could not be identified, a method for daily “net migration” was been developed to estimate the direction of migration. The results showed that net migration of spawning-size trout was greater upstream than downstream. Net upstream migration of spawning size trout tended to increase over time, but not the net downstream migration. There was no difference between net upstream and net downstream migration smolt-size trout, but the net downstream migration smolt-size trout increased over time. The study showed that there was substantial use of Billsta nature-like fishway for brown trout of both spawning- and smolt-sizes, for both upstream and downstream migration. The migration pattern was partly as expected but, upstream migration of smolt-size trout suggests that there is a considerable population of stationary trout passing the fish-counter. The study highlights the importance of monitoring the results of the restoration and implementing improvement measures where necessary. Billstaån has regained open migration pathways, but more time is needed to evaluate its effect and find out if the ecosystem works so that Storsjöns unique, large sized, migratory brown trout stocks once again have the conditions to complete their lifecycle in Billstaån. / Fria vandringsvägar är avgörande för öringens förmåga att återkolonisera lek- och uppväxthabitat, vid fungerande lek- och smoltvandring kan öringen fullborda sin livscykel. Vattenkraftsproduktion har skapat vandringshinder och naturlika fiskvägar är en åtgärd för att återskapa konnektivitet. Syftet med den här kandidatuppsatsen var att ta reda på hur den nedersta naturlika fiskvägen, skapad 2016 vid Billsta kraftverk i mellersta Sverige, nyttjades av vandrande öringar för uppströms och nedströms passage och observera om vandringsmönstret förändrades över tid, mellan 2018–2020. Rådatan kommer från en automatisk fiskräknare som funnits placerad uppströms den naturlika fiskvägen. För att analysera datan delades öringen in efter två längdstorlekar, lek- och smoltstorlek, enligt kriterier från Havs- och vattenmyndigheten. Eftersom individuell fisk inte gick att identifiera har en metod för daglig ”nettovandring” utarbetats för att uppskatta vandringens riktning. Resultatet visade att fler öringar i lekfiskstorlek nettouppvandrade än nettonedvandrade. Nettouppvandring av lekfiskstorlek tenderade att öka över tid men inte nettonedvandringen. Det var ingen skillnad mellan nettoupp- och nettonedvandrande öring i smoltstorlek, men nettonedvandringen av öring i smoltstorlek ökade över tid. Studien visade att Billsta naturlika fiskväg nyttjades väl av öring i både lekfisk- och smoltstorlek för både uppströms- och nedströmsvandring. Vandringsmönstret var delvis som förväntat, men när det gäller smoltstorlekens vandring var det snarare bäcköringens vandring än smoltens vandringsmönster som analyserades. Studien belyser vikten av att övervaka resultatet av restaureringen och implementera förbättringsåtgärder där så behövs. Billstaåån har återfått fria vandringsvägar men mer tid behövs för att utvädera dess effekt och ta reda på om ekosystemet fungerar så att Storsjöns unika, storvuxna, lekvandrande öringstam återigen fått förutsättningar att fullborda sin livscykel i Billstaån.

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The biopharmaceutical industry has experienced remarkable progress in the upstream production capacity of life-saving proteins. This is while the downstream processing has failed to keep pace, including unit operations which are working close to their physical limit with no economy of scale. Column chromatography which is an integral unit in different stages of downstream purification is considered as the major bottleneck in this section. The packed-bed resin media is costly and the processes are labor-intensive and extremely time consuming. Membrane chromatography which uses a stack of adsorptive membranes as the chromatographic media is one of the most promising alternatives for conventional chromatography techniques. The performance of membrane adsorbers is consistent over a wide range of flow rates which is owing to the dominance of convective solute transport as opposed to the diffusion-based nature of mass transfer within the pores of the resin beads. This translates to much higher productivity and considerably lower buffer consumption (even as high as 95%), leading to much lower overall processing costs. The other advantages are significantly lower footprints and decreased pressure drops, both contributing to diminished capital costs. Membrane adsorbers are greatly scalable and used in a single-use manner. The latter eliminates the cleaning and validation steps and brings about much shorter processing times and higher flexibility in process development. Due to the performance advantages of membrane chromatography, this technique is now widely used in purification of high volumes of samples in late-stage polishing. Currently available membrane adsorbers have radial-flow spiral-wound configuration with high frontal surface area to bed height ratio according to which dilute impurities are removed in a flow-through format at very high flow rates and low pressure drops. Nevertheless, they fail to give high-resolution for bind-and-elute separations which makes them unsuitable for many unit operations, highly restricting their application. Severe design deficiencies such as large dead volumes and varying membrane area over the bed height result in broad and poorly resolved peaks. Herein, a novel device design was successfully developed which addresses the abovementioned shortcomings. The laterally-fed membrane chromatography (LFMC) devices house a stack of rectangular membrane sheets with two rectangular lateral channels on both sides of the stack as the feed and permeate channels. The design offers balanced pressure over the sides of the stack as well as even solute flow path lengths due to which the solute residence time is very uniform. Also, the small dead volumes minimize the dispersion effects. These features make the LFMC technology highly suitable for bind-and-elute applications, the improvement which is brought about by a simple design. The devices are easy to fabricate and highly scalable. The LFMC devices containing cation-exchange (CEX) membranes with 7 mL bed volume were examined for bind-and-elute separation where they outperformed the equivalent commercially available radial-flow devices. The design was further modified to give even lower dead volumes and more cost-effective fabrication. The latest embodiment of the device gave resolutions which were comparable with the ones obtained with the commercially packed resin columns in 1 mL and 5 mL scale with consistency over wide range of flow rates. The results were all acquired using a three component model protein system. Upon the approval of suitability of the device for bind-and-elute separation, the CEX-LFMC was used for purification of monoclonal antibodies (mAbs), the largest class of biopharmaceuticals. The device showed great performance in separation of mAb charge variants when extensively shallow gradients (60 membrane bed volumes) were required. The devices offered very stable conductivity gradients at high flow rates. LFMC devices in three different preparative scales gave great performance in separation of mAb aggregates which was approved for different mAb samples. The other application studied with the CEX-LFMC devices was the single-step preparative purification of mono-PEGylated proteins which is as well very challenging due to the physicochemical similarities between the target molecules and the impurities. Collectively, the LFMC devices combine the high-resolution with high-productivity which is highly desirable in downstream purification of biological molecules with great potential to expand the application of membrane chromatography. Finally, the LFMC devices were modified to adapt the analytical scale where they were integrated with a stack of hydrophilized PVDF membranes. The device successfully delivered ultra-fast separation of mAb aggregates in less than 1.5 minutes based on hydrophobic interaction membrane chromatography (HIMC). The assay times achieved with the HI-LFMC technique outclassed the currently available ultra-high performance chromatography (UPLC) methods at the same time with being extremely cost-effective. The application of the LFMC technology in analytical scale has great potential to offer cheap and rapid analysis in process development and quality control section of biopharmaceutical manufacturing. / Thesis / Doctor of Philosophy (PhD)

In the literature, the impact of multinationality on the valuation of multinational companies is heavily debated. To understand this impact on valuation, we need to clarify whether and how multinationality affects systematic risk. For this purpose, we analyze the state of research concerning the impact of corporate multinationality on systematic risk, conducting a systematic literature review of 35 studies and a univariate meta-analysis based on 20 studies. We test the predictions of the upstream–downstream hypothesis and the increasing capital market integration hypothesis on the basis of a meta-regression analysis of 17 studies. Our results provide no empirical support for the upstream–downstream hypothesis. However, they corroborate the capital market integration hypothesis in a more radical manner than expected: whereas multinationality seemed to have a risk-reducing effect until the beginning of the 1990s, since then its impact appears to have shifted. We find a risk-increasing effect for multinationality from 1990 on. Our results have important implications for academic research and managerial practice.

Today, the availability of methods for the activity-preserving and cost-efficient downstream processing of enzymes forms a major bottleneck to the use of these valuable tools in technical processes. A promising technology appears to be foam fractionation, which utilizes the adsorption of proteins at a gas–liquid interface. However, the employment of surfactants and the dependency of the applicability on individual properties of the target molecules are considerable drawbacks. Here, we demonstrate that a reversible fusion of the large, surface-active protein Ranaspumin-2 (Rsn-2) to a β-lactamase (Bla) enabled both surfactant-free formation of a stable foam and directed enrichment of the enzyme by the foaming. At the same time, Bla maintained 70% of its catalytic activity, which was in stark contrast to the enzyme without fusion to Rsn-2. Rsn-2 predominantly mediated adsorption. Comparable results were obtained after fusion to the structurally more complex penicillin G acylase (PGA) as the target enzyme. The results indicate that using a surface-active protein as a fusion tag might be the clue to the establishment of foam fractionation as a general method for enzyme downstream processing.

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