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Background: The outbreak of COVID-19 generated challenges for both employers andemployees over a broad spectrum of industries. People were recommended to observe socialdistancing and lockdowns and/or curfews for non-essential businesses were implemented. Thisglobal situation catalyzed process innovation and a transition from traditional work settings,specifically on-site work, to a remote work setting where employees use online communicationrequiring homes with computers and high-speed internet. Purpose: This thesis explores how work settings changed due to the pandemic, how differentwork settings affect work-related collaborations which is a cornerstone in the innovationprocess, but also to investigate differences amongst personality traits in various work settings. Methodology: The research presented herein is based on a quantitative survey of 156respondents from a multitude of industries including several countries. The survey wasdesigned using the Likert scale to capture how respondents perceived various aspects ofcollaboration before, during, and after the COVID-19 pandemic. In addition to respondent’sperceptions, relevant demographic information was collected. The survey results were analyzedusing descriptive statistics, CFA, SEM analysis, and statistical tests. Results and Analysis: Differences between work settings were found regarding certain aspectsof collaboration. The most notable was that informal collaboration was limited when workingfrom home. The most important aspects of collaboration are to be able to trust collaborativepartners and feel mutual respect. Conclusions: Employers need to develop digital communication tools and collaborationpractices when adopting a hybrid workplace. Informal interactions are an important aspect ofcollaboration, and these interactions are limited when working from home. Management needsto nurture an atmosphere of trust and mutual respect for successful collaboration. Recommendations for future research: Studies are reco

O-methyl-serine dodecylamine hydrochloride (MSDH) is a detergent that accumulates selectively in lysosomes, a so-called lysosomotropic detergent, with unexpected chemical properties. At physiological pH, it spontaneously forms vesicles, which disassemble into small aggregates (probably micelles) below pH 6.4. In this study, we characterize the interaction between MSDH and liposomes at different pH and correlate the findings to toxicity in human fibroblasts. We find that the effect of MSDH on lipid membranes is highly pH-dependent. At neutral pH, the partitioning of MSDH into the liposome membrane is immediate and causes the leakage of small fluorophores, unless the ratio between MSDH and lipids is kept low. At pH 5, the partitioning of MSDH into the membrane is kinetically impeded since MSDH is charged and a high ratio between MSDH and the lipids is required to permeabilize the membrane. When transferred to cell culture conditions, the ratio between MSDH and plasma membrane lipids must therefore be low, at physiological pH, to maintain plasma membrane integrity. Transmission electron microscopy suggests that MSDH vesicles are taken up by endocytosis. As the pH of the endosomal compartment progressively drops, MSDH vesicles disassemble, leading to a high concentration of increasingly charged MSDH in small aggregates inside the lysosomes. At sufficiently high MSDH concentrations, the lysosome is permeabilized, the proteolytic content released to the cytosol and apoptotic cell death is induced., Funding agencies: The Swedish Cancer Society (KÖ), Konung Gustav V ochDrottning Victorias Frimurarestiftelse (KÖ) and Stiftelseförvaltningen vid Region Östergötland (AMVG and IE).

Lysosomotropic detergents (LDs) selectively rupture lysosomal membranes through mechanisms that have yet to be characterized. A consensus view, currently, holds that LDs, which are weakly basic, diffuse across cellular membranes as monomers in an uncharged state, and via protonation in the acidic lysosomal compartment, they become trapped, accumulate, and subsequently solubilize the membrane and induce lysosomal membrane permeabilization. Here we demonstrate that the lysosomotropic detergent O-methyl-serine dodecylamide hydrochloride (MSDH) spontaneously assembles into vesicles at, and above, cytosolic pH, and that the vesicles disassemble as the pH reaches 6.4 or lower. The aggregation commences at concentrations below the range of those used in cell studies. Assembly and disassembly of the vesicles was studied via dynamic light scattering, zeta potential measurements, cryo-TEM, and fluorescence correlation spectroscopy and was found to be reversible via control of the pH. Aggregation of MSDH into closed vesicles under cytosolic conditions is at variance with the commonly held view of LD behavior, and we propose that endocytotic pathways should be considered as possible routes of LD entry into lysosomes. We further demonstrate that MSDH vesicles can be loaded with fluorophores via a solution transition from low to high pH, for subsequent release when the pH is lowered again. The ability to encapsulate molecular cargo into MSDH vesicles together with its ability to disaggregate at low pH and to permeabilize the lysosomal membrane presents an intriguing possibility to use MSDH as a delivery system., QC 20170202

Lysosomotropic detergents (LDs) selectively rupture lysosomal membranes through mechanisms that have yet to be characterized. A consensus view, currently, holds that LDs, which are weakly basic, diffuse across cellular membranes as monomers in an uncharged state, and via protonation in the acidic lysosomal compartment, they become trapped, accumulate, and subsequently solubilize the membrane and induce lysosomal membrane permeabilization. Here we demonstrate that the lysosomotropic detergent O-methyl-serine dodecylamide hydrochloride (MSDH) spontaneously assembles into vesicles at, and above, cytosolic pH, and that the vesicles disassemble as the pH reaches 6.4 or lower. The aggregation commences at concentrations below the range of those used in cell studies. Assembly and disassembly of the vesicles was studied via dynamic light scattering, zeta potential measurements, cryo-TEM, and fluorescence correlation spectroscopy and was found to be reversible via control of the pH. Aggregation of MSDH into closed vesicles under cytosolic conditions is at variance with the commonly held view of LD behavior, and we propose that endocytotic pathways should be considered as possible routes of LD entry into lysosomes. We further demonstrate that MSDH vesicles can be loaded with fluorophores via a solution transition from low to high pH, for subsequent release when the pH is lowered again. The ability to encapsulate molecular cargo into MSDH vesicles together with its ability to disaggregate at low pH and to permeabilize the lysosomal membrane presents an intriguing possibility to use MSDH as a delivery system., Funding Agencies|Swedish Research Council [2013-3214]; Konung Gustaf V och Drottning Victorias Frimurarestiftelse; Stiftelseforvaltningen Region Ostergotland [LIO-570261]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; Linkoping University

The antifouling (AF) properties of oligo(lactose)-based self-assembled monolayers (SAMs), using four different proteins, zoospores of the green alga Ulva linza and cells of the diatom Navicula incerta, were investigated. The SAM-forming alkylthiols, which contained 1, 2 or 3 lactose units, showed significant variation in AF properties, with no differences in wettability. Non-specific adsorption of albumin and pepsin was low on all surfaces. Adsorption of lysozyme and fibrinogen decreased with increasing number of lactose units in the SAM, in agreement with the generally observed phenomenon that thicker hydrated layers provide higher barriers to protein adsorption. Settlement of spores of U. linza followed an opposite trend, being greater on the bulkier, more hydrated SAMs. These SAMs are more ordered for the larger saccharide units, and it is therefore hypothesized that the degree of order, and differences in crystallinity or stiffness between the surfaces, is an important parameter regulating spore settlement on these surfaces., Funding Agencies|European Community [23797]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; ONR (USA) [N0001-08-1-0010]

This thesis covers different topics in the field of synthetic organic chemistry combined with the field of surface science and glycobiology. First, the text presents a series of orthogonally protected oligosaccharides (tri-, penta-, and heptasaccharides) of varying length and structures, which are synthesized with the aim of developing novel heterobifunctional biocompatible cross-linkers. Successful conjugation with different chemical handles is also described and used to illustrate the potential implementation of defined carbohydrate based compounds have potential use in biosensing applications. The results of incubation experiments using living cells indicate that the linker is incorporated into cell surfaces and enriched in microdomains. Second, synthesis of various saccharide-terminated alkane thiols immobilized on gold surfaces is reported. The protein adsorption and antifouling characteristics of these surfaces were investigated using model proteins and the common fouling organisms, Ulva linza and Balanus amphitrite. Further, oligo(lactose)-based thiols (di-, tetra-, and hexasaccharides) were synthesized and immobilized on gold nanoparticles to investigate how well these rigid, rod-like oligosaccharides can stabilize such nanoparticles for future use in constructing hybrid nanoparticles. Finally, the thesis describes synthesis of a systematic series of oligo(ethylene) glycols possessing either hydrogen- or methyl-terminated groups. Investigation of the fundamental characteristics of self-assembled monolayers, will give important insights into the design of protein repellant surfaces.

The synthesis of four bifunctionalized orthogonally N-protected oligosaccharides derived from lactose and mannose, intended as cross-linking derivatives, is described. The amino sugar at the non-reducing end is derivatized with an N-Boc-protected glycine moiety, and further connected to either a mannose (1→6) disaccharide or (1→3) lactose units (one, two or three) resulting in tri-, penta-, or heptasaccharides. All of the synthesized oligosaccharides have an Nbenzyloxycarbonyl-aminoethyl residue at the reducing end. The fully orthogonal N-Boc/N-Cbz protection group pattern enables further conjugation/derivatization and results in a hydrophilic cross-linking molecule. It was found that the order of the final synthetic steps were crucial to avoid acyl migration. A suitable amide coupling protocol has been applied to introduce the NBoc-protected glycine moiety in alcoholic solvent. The synthesized oligosaccharides will provide a model system to investigate the influence of length, structure and flexibility. The function of the cross-linked substituents thereby provide valuable insights into the role as a spacer molecule.

Two series of oligo (ethylene glycol) (OEG) thiol compounds HS-(CH2CH2O)nR with R = CH3, H and n = 5, 6, 7, have been synthesized and used to form self-assembled monolayers (SAMs) on gold. The data from null ellipsometry, infrared reflection-absorption spectroscopy and ab initio calculations of this type of OH- and CH3-terminated OEG SAMs are used to examine the rarely addressed in-SAM orientation of oligo (ethylene glycols) and to provide detailed assignments of infrared bands in the fingerprint and CH-stretching regions. Based on these results, a new spectral band has been observed at 2947 cm-1 and identified by the firstprinciple calculations as localized vibrations that are specific for hydrogen-terminated OEG thiolate SAMs. This band can be used as an indicator of a high crystalline like ordering. It is further more stressed that theory agrees with the experimentally obtained CH-stretching spectra remarkably well if, and only if, the OEG helix axis within studied SAMs is tilted by about 20o with respect to the surface normal.

When cross-linking biomolecules to surfaces or to other biomolecules, the use of appropriate spacer molecules is of great importance. Mimicking the naturally occurring spacer molecules will give further insight into their role and function, possibly unveil important issues regarding the importance of the specificity of carbohydrate-based anchor moieties, in e.g., glycoproteins and glycosylphosphatidylinositols. Herein, we present the synthesis of a lactoside-based trisaccharide, potentially suitable as a heterobifunctional bioorthogonal linker molecule whereon valuable chemical handles have been conjugated. An amino-derivative having thiol functionality shows promise as novel SPR-surfaces. Furthermore, the trisaccharide has been conjugated to a cholesterol moiety in combination with a fluorophore which successfully assemble on the cell surface in lipid microdomains, possibly lipid-rafts. Finally, a CuI-catalyzed azide-alkyne cycloaddition reaction (CuAAC) confirms the potential use of oligosaccharides as bioorthogonal linkers in chemical biology.

We describe the synthesis of a series of mono-, di-, and trisaccharide-functionalized alkanethiols as well as the formation of fouling-resistant self-assembled monolayers (SAMs) from these. The SAls,,Is were characterized using ellipsometry, wetting measurements, and infrared reflection absorption spectroscopy (WAS). We show that the structure of the carbohydrate moiety affects the packing density and that this also alters the alkane chain organization. Upon increasing the size of the sugar moieties (from mono- to di- and trisaccharides), the structural qualities of the monolayers deteriorated with increasing disorder, and for the trisaccharide, slow reorganization dynamics in response to changes in the environmental polarity were observed. The antifouling properties of these SAMs were investigated through protein adsorption experiments from buffer solutions as well as settlement (attachment) tests using two common marine fouling species, zoospores of the green macroalga Ulva linza and cypris larvae of the barnacle Balanus amphitrite. The SAMs showed overall good resistance to fouling by both the proteins and the tested marine organisms. To improve the packing density of the SAMs with bulky headgroups, we employed mixed SAMs where the saccharide-thiols are diluted with a filler molecule having a small 2-hydroxyethyl headgroup. This method also provides a means by which the steric availability of sugar moieties can be varied, which is of interest for specific interaction studies with surface-bound sugars. The results of the surface dilution study and the low nonspecific adsorption onto the SAMs both indicate the feasibility of this approach., Funding Agencies|AMBIO|NMP-CT-2005-011827|European Commission

The ability of fabricating surfaces with low non-specific protein adhesion is of great interest in material science. Studies have shown that self-assembled monolayers (SAMs) covered with carbohydrates moieties have protein resistant characteristics and even marine anti-fouling properties.[1,2]The presented results describe the synthesis of oligosaccharides originating from lactose and mannose. We have also set out to investigate if these orthogonally protected oligosaccharides can be used as spacer molecules and their performance in protein adsorption studies. Using the selected divergence enables incorporation into various surface systems e.g. gold nanoparticles, vesicles or as a conjugate between different macromolecules. [1] Hederos, M.; Konradsson, P.; Liedberg, B.; Langmuir, 2005, 21, 2971-2980.[2] Fyrner, T.; Konradsson, P.; et. al.; Submitted, 2010.

Olfaction may play an important role in regulating bird behavior, and has been suggested to be involved in feather-pecking. We investigated possible differences in the body odors of red junglefowl females by using an automated olfactometer which assessed the ability of trained mice to discriminate between the odors of uropygial gland secretions (the main carrier of potential individual odors in chickens) of six feather-pecked and six non-pecked birds. All mice were clearly able to discriminate between all individual red junglefowl odors, showing that each bird has an individual body odor. We analyzed whether it was more difficult to discriminate between the odors of two feather-pecked, or two non-pecked birds, than it was to discriminate between the odors of two randomly selected birds. This was not the case, suggesting that feather-pecked birds did not share a common odor signature. Analyses using gas chromatography and mass spectrometry showed that the composition of aliphatic carboxylic acids in uropygial gland secretions differed consistently between individuals. However, chemical composition did not vary according to feather-pecking status. We conclude that red junglefowl have individual body odors which appear to be largely based on differences in the relative abundance of aliphatic carboxylic acids, but there is no evidence of systematic differences between the body odors of pecked and non-pecked birds., Original Publication: Anna-Carin Karlsson, Per Jensen, Mathias Elgland, Katriann Laur, Timmy Fyrner, Peter Konradsson and Matthias Laska, Red junglefowl have individual body odors, 2010, JOURNAL OF EXPERIMENTAL BIOLOGY, (213), 10, 1619-1624. http://dx.doi.org/10.1242/jeb.040279 Copyright: The Company of Biologists Ltd http://www.biologists.com