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We have used approximately 40 fs pulses from a Ti:sapphire laser to investigate the ultrafast energy transfer and relaxation dynamics in the light-harvesting pigment-proteins of photosynthetic purple bacteria. Our results reveal two new features, not earlier observed in light-harvesting pigments: (1) ultrafast relaxation characterized by a time constant of approximately 20 fs, which we interpret a

Using ≈ 40 fs pulses we have observed coherent nuclear motions in intact membrane bound photosynthetic light-harvesting pigment-protein complexes. Computer simulations based on the harmonic Franck-Condon approximation and the Langevin equation describe qualitatively well the temperature and pulse wavelength dependence of the oscillations, indicating the possibility to observe higher harmonics of t

The light-harvesting apparatus of the photosynthetic bacterium Rhodobacter sphaeroides is composed of a peripheral LH2 complex which directs excitation energy to the LH1/reaction center core. The puf BA genes encoding the LH1 polypeptides have been deleted, producing a photosynthetically-competent strain which contains LH2 and reaction centers. Time-resolved absorption and fluorescence measurement

The road to a Nobel Prize is usually long and winding. This article tracks theroad to Robert Fogel’s and Douglass North’s shared prize in economics in 1993through Lennart Jörberg’s correspondence from 1965 to 1989. Jörberg, for almosttwenty years professor and head of the Department of Economic History at LundUniversity, had during two year-long visits in the United States in the 1950s and1960s de

Kan energibalansen vid träning påverka benkvalitet? Hur påverkas de små byggstenarna i benet när kroppen får för lite energi men samtidigt utsätts för hård träningsbelastning? Denna studie undersöker hur man kan visualisera både kollagenfibrer samt bencellernas kommunikationsnätverk i benvävnad hos möss med, respektive utan relativ energibrist (RED-S). Relativ energibrist inom idrott (RED-S) uppRelative Energy Deficiency in Sport (RED-S) is a condition arising when dietary energy intake is insufficient to meet the combined demands of training and normal physiological functions. RED-S negatively impacts bone health, and increases the risk of stress fractures. Yet, its effects on bone matrix organization and overall bone quality is not well understood. Collagen and the osteocyte cells'

De allra flesta läkarbesöken för infektioner sker i primärvården. En hög och olämplig antibiotikaförskrivning innebär risker inte bara för biverkningar för patienten utan också för ökad antibiotikaresistens. Stora ansträngningar har gjorts för att minska antibiotikaförskrivning. Under covid-19-pandemin såg vi att antalet infektioner och antalet antibiotikaförskrivningar halverades. Hur kan vi fortThere is considerable variation in antibiotic prescribing rates among physicians, primary healthcare centres, and countries. If the variation could be reduced, the antibiotic prescribing could decrease.Methods. The thesis is based on real-world data from two databases containing infection visits: The Kronoberg Infection Database in Primary Care (infection visits in the Kronoberg region from 2006 t

Abstract: For patients with locally advanced head and neck tumours or other defects, the preferred curative treatment is extensive reconstructive surgery using free microvascular flap(s), oftentimes followed by postoperative radiotherapy. The procedure offers superior functional and aesthetic advantages, but the treatment course is long and complex and burdened with a significant risk of complicat

Mandatory human rights and environmental due diligence (HREDD) policies seem to represent a pathbreaking shift from voluntary measures to binding rules for global supply chains. Yet these policies endorse a “smart-mix” of voluntary and mandatory measures, and risk over-reliance on questionable private-sector assurances. In this paper, we ask how businesses framed these private/voluntary efforts in

Executive functions are a set of cognitive skills enabling goal‑directed behaviours. Both mammals and birds have highly proficient executive functions, despite diverging from each other around 360 million years ago. This cognitive convergence is due to both taxa being tachymetabolic endotherms. They can maintain a stable and elevated body temperature with a high metabolism. However, in order to su

Ribbed channel flows play a crucial role in various engineering systems where turbulence enhancement and improved heat transfer are required, such as in turbine blade cooling and combustor wall applications. Numerical simulations have emerged as an essential tool for analyzing the intricate turbulence dynamics and flow separation phenomena, which are fundamental for optimizing the channel performa

Magic Angle Spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is limited in spectral resolution by the spinning frequency of rotors that hold the analyte. Traditional yttria-stabilized zirconia (YSZ) rotors have mechanical constraints that typically limit spinning frequencies of 0.7 mm rotors to ωr/2π ∼ 110 kHz. These frequencies are not sufficient to achieve resolution comparable to th

This work presents a comparative luminescence study of Pr3+ doped phase-pure BaLuF5 and mixed-phase BaLu2F8 – BaLuF5 materials synthesized via a hydrothermal route. The spectroscopic studies were mainly performed for phase-pure BaLuF5 and two mixed-phase materials, which, according to structural and phase compositional analysis, contained 90 or 70 wt% of orthorhombic BaLu2F8 and 10 or 30 wt% of cu

Bovine mastitis is a continuous problem in the dairy industry. The infection has significant impact on health and welfare of animals and causes financial losses for the farmers and the dairy industry. A key bacterium associated with bovine mastitis is Staphylococcus aureus (S. aureus). It produces different exotoxins including more than 24 different staphylococcal enterotoxins and toxic shock synd