| 1. |
- Speliotes, Elizabeth K., et al.
(författare)
-
Association analyses of 249,796 individuals reveal 18 new loci associated with body mass index
- 2010
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:11, s. 937-948
-
Tidskriftsartikel (refereegranskat)abstract
- Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10−8), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation.
|
|
| 2. |
- Andersson, Björn, et al.
(författare)
-
Advective collisions
- 2007
-
Ingår i: Europhysics Letters. - : IOP Publishing. - 0295-5075 .- 1286-4854. ; 80
-
Tidskriftsartikel (refereegranskat)
|
|
| 3. |
- Andersson, Rebecca, et al.
(författare)
-
Differential role of cytosolic Hsp70s in longevity assurance and protein quality control
- 2021
-
Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7404 .- 1553-7390. ; 17:1
-
Tidskriftsartikel (refereegranskat)abstract
- 70 kDa heat shock proteins (Hsp70) are essential chaperones of the protein quality control network; vital for cellular fitness and longevity. The four cytosolic Hsp70's in yeast, Ssa1-4, are thought to be functionally redundant but the absence of Ssa1 and Ssa2 causes a severe reduction in cellular reproduction and accelerates replicative aging. In our efforts to identify which Hsp70 activities are most important for longevity assurance, we systematically investigated the capacity of Ssa4 to carry out the different activities performed by Ssa1/2 by overproducing Ssa4 in cells lacking these Hsp70 chaperones. We found that Ssa4, when overproduced in cells lacking Ssa1/2, rescued growth, mitigated aggregate formation, restored spatial deposition of aggregates into protein inclusions, and promoted protein degradation. In contrast, Ssa4 overproduction in the Hsp70 deficient cells failed to restore the recruitment of the disaggregase Hsp104 to misfolded/aggregated proteins, to fully restore clearance of protein aggregates, and to bring back the formation of the nucleolus-associated aggregation compartment. Exchanging the nucleotide-binding domain of Ssa4 with that of Ssa1 suppressed this 'defect' of Ssa4. Interestingly, Ssa4 overproduction extended the short lifespan of ssa1 Delta ssa2 Delta mutant cells to a lifespan comparable to, or even longer than, wild type cells, demonstrating that Hsp104-dependent aggregate clearance is not a prerequisite for longevity assurance in yeast. Author summary All organisms have proteins that network together to stabilize and protect the cell throughout its lifetime. One of these types of proteins are the Hsp70s (heat shock protein 70). Hsp70 proteins take part in folding other proteins to their functional form, untangling proteins from aggregates, organize aggregates inside the cell and ensure that damaged proteins are destroyed. In this study, we investigated three closely related Hsp70 proteins in yeast; Ssa1, 2 and 4, in an effort to describe the functional difference of Ssa4 compared to Ssa1 and 2 and to answer the question: What types of cellular stress protection are necessary to reach a normal lifespan? We show that Ssa4 can perform many of the same tasks as Ssa1 and 2, but Ssa4 doesn't interact in the same manner as Ssa1 and 2 with other types of proteins. This leads to a delay in removing protein aggregates created after heat stress. Ssa4 also cannot ensure that misfolded proteins aggregate correctly inside the nucleus of the cell. However, this turns out not to be necessary for yeast cells to achieve a full lifespan, which shows us that as long as cells can prevent aggregates from forming in the first place, they can reach a full lifespan.
|
|
| 4. |
- Ardi, Shanai, et al.
(författare)
-
A Case Study of Introducing Security Risk Assessment in Requirements Engineering in a Large Organization
- 2023
-
Ingår i: SN Computer Science. - : Springer. - 2661-8907. ; 4:5
-
Tidskriftsartikel (refereegranskat)abstract
- Software products are increasingly used in critical infrastructures, and verifying the security of these products has become a necessary part of every software development project. Effective and practical methods and processes are needed by software vendors and infrastructure operators to meet the existing extensive demand for security. This article describes a lightweight security risk assessment method that flags security issues as early as possible in the software project, namely during requirements analysis. The method requires minimal training effort, adds low overhead, and makes it possible to show immediate results to affected stakeholders. We present a longitudinal case study of how a large enterprise developing complex telecom products adopted this method all the way from pilot studies to full-scale regular use. Lessons learned from the case study provide knowledge about the impact that upskilling and training of requirements engineers have on reducing the risk of malfunctions or security vulnerabilities in situations where it is not possible to have security experts go through all requirements. The case study highlights the challenges of process changes in large organizations as well as the pros and cons of having centralized, distributed, or semi-distributed workforce for security assurance in requirements engineering.
|
|
| 5. |
- Aziz, Imran, et al.
(författare)
-
Effects of proton irradiation on 60 GHz CMOS transceiver chip for multi-Gbps communication in high-energy physics experiments
- 2019
-
Ingår i: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :8, s. 5391-5396
-
Tidskriftsartikel (refereegranskat)abstract
- This article presents the experimental results of 17 MeV proton irradiation on a 60 GHz low power, half-duplex transceiver (TRX) chip implemented in 65 nm CMOS technology. It supports short range point-to-point data rate up to 6 Gbps by employing on-off keying (OOK). To investigate the irradiation hardness for high-energy physics (HEP) applications, two TRX chips were irradiated with total ionising doses (TID) of 74 and 42 kGy and fluence of 1.4 x 10(14)N(eq)/cm(2) and 0.8 x 10(14)N(eq)/cm(2) for RX and TX modes, respectively. The chips were characterised by pre- and post-irradiation analogue voltage measurements on different circuit blocks as well as through the analysis of wireless transmission parameters like bit error rate (BER), eye diagram, jitter etc. Post-irradiation measurements have shown certain reduction in performance but both TRX chips have been found operational through over the air measurements at 5 Gbps. Moreover, very small shift in the carrier frequency was observed after the irradiation.
|
|
| 6. |
- Berg, Kristian, 1959-, et al.
(författare)
-
Kaliningrad : byggnadsvård kan hindra kulturell katastrof
- 2000
-
Ingår i: Kulturmiljövård. - Stockholm : Riksantikvarieämbetet. - 1100-4800. ; :1, s. 73-77
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- -Jag har i hela mitt liv fått höra historien om den underjordiska gömda staden i Kaliningrad. Under ytan av den stad vi nu ser skulle det finnas en annan, med alla de historiska lämningar och rikedomar som detta Königsberg en gång var förknippat med.
|
|
| 7. |
- Berndt, Sonja I., et al.
(författare)
-
Genome-wide meta-analysis identifies 11 new loci for anthropometric traits and provides insights into genetic architecture
- 2013
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:5, s. 501-U69
-
Tidskriftsartikel (refereegranskat)abstract
- Approaches exploiting trait distribution extremes may be used to identify loci associated with common traits, but it is unknown whether these loci are generalizable to the broader population. In a genome-wide search for loci associated with the upper versus the lower 5th percentiles of body mass index, height and waist-to-hip ratio, as well as clinical classes of obesity, including up to 263,407 individuals of European ancestry, we identified 4 new loci (IGFBP4, H6PD, RSRC1 and PPP2R2A) influencing height detected in the distribution tails and 7 new loci (HNF4G, RPTOR, GNAT2, MRPS33P4, ADCY9, HS6ST3 and ZZZ3) for clinical classes of obesity. Further, we find a large overlap in genetic structure and the distribution of variants between traits based on extremes and the general population and little etiological heterogeneity between obesity subgroups.
|
|
| 8. |
- Bi, Zhaoxia, et al.
(författare)
-
InGaN Platelets : Synthesis and Applications toward Green and Red Light-Emitting Diodes
- 2019
-
Ingår i: Nano Letters. - : American Chemical Society. - 1530-6984 .- 1530-6992. ; 19:5, s. 2832-2839
-
Tidskriftsartikel (refereegranskat)abstract
- In this work, we present a method to synthesize arrays of hexagonal InGaN submicrometer platelets with a top c-plane area having an extension of a few hundred nanometers by selective area metal-organic vapor-phase epitaxy. The InGaN platelets were made by in situ annealing of InGaN pyramids, whereby InGaN from the pyramid apex was thermally etched away, leaving a c-plane surface, while the inclined {101Ì1} planes of the pyramids were intact. The as-formed c-planes, which are rough with islands of a few tens of nanometers, can be flattened with InGaN regrowth, showing single bilayer steps and high-quality optical properties (full width at half-maximum of photoluminescence at room temperature: 107 meV for In 0.09 Ga 0.91 N and 151 meV for In 0.18 Ga 0.82 N). Such platelets offer surfaces having relaxed lattice constants, thus enabling shifting the quantum well emission from blue (as when grown on GaN) to green and red. For single InGaN quantum wells grown on the c-plane of such InGaN platelets, a sharp interface between the quantum well and the barriers was observed. The emission energy from the quantum well, grown under the same conditions, was shifted from 2.17 eV on In 0.09 Ga 0.91 N platelets to 1.95 eV on In 0.18 Ga 0.82 N platelets as a result of a thicker quantum well and a reduced indium pulling effect on In 0.18 Ga 0.82 N platelets. On the basis of this method, prototype light-emitting diodes were demonstrated with green emission on In 0.09 Ga 0.91 N platelets and red emission on In 0.18 Ga 0.82 N platelets.
|
|
| 9. |
- Biferale, L., et al.
(författare)
-
Zermelo's problem: Optimal point-to-point navigation in 2D turbulent flows using reinforcement learning
- 2019
-
Ingår i: Chaos. - : AIP Publishing. - 1054-1500. ; 29:10
-
Tidskriftsartikel (refereegranskat)abstract
- To find the path that minimizes the time to navigate between two given points in a fluid flow is known as Zermelo's problem. Here, we investigate it by using a Reinforcement Learning (RL) approach for the case of a vessel that has a slip velocity with fixed intensity, Vs, but variable direction and navigating in a 2D turbulent sea. We show that an Actor-Critic RL algorithm is able to find quasioptimal solutions for both time-independent and chaotically evolving flow configurations. For the frozen case, we also compared the results with strategies obtained analytically from continuous Optimal Navigation (ON) protocols. We show that for our application, ON solutions are unstable for the typical duration of the navigation process and are, therefore, not useful in practice. On the other hand, RL solutions are much more robust with respect to small changes in the initial conditions and to external noise, even when V-s is much smaller than the maximum flow velocity. Furthermore, we show how the RL approach is able to take advantage of the flow properties in order to reach the target, especially when the steering speed is small. Published under license by AIP Publishing.
|
|
| 10. |
- Bonfils, Anthony, 1994-
(författare)
-
The growth of waves by wind as a problem in nonequilibrium statistical mechanics
- 2020
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In 1948, Casimir predicted a net attractive force between two perfectly conducting parallel plates due to electromagnetic vacuum fluctuations. By analogy, the interaction of two ships on a wavy sea has been named Maritime Casimir effect. This is an example of force generation in non-equilibrium systems. Lee, Vella and Wettlaufer showed it to be oscillatory as it is induced by the sharply peaked energy spectrum measured in the sixties by Pierson and Moskowitz for a fully developed sea; a sea whose state is independent of the distance over which the wind blows and the time for which it has been blowing. The aim of this project is to construct a theory for that spectrum and understand how the Maritime Casimir effect emerges from wind-wave interaction. Waves in the absence of wind, so-called water waves, are mainly characterized by dispersion and weak non-linearity. The coupling of both results in the instability of a wave packet to side-band perturbations in deep water. The growth rate can be calculated thanks to a non-linear Schrödinger equation, which is a universal model for weakly non-linear waves in a dispersive medium. Furthermore, this instability can be understood in the even more general framework of resonant wave-wave interaction. The evolution of deep water gravity waves is actually a sum of four-wave interaction processes and triadic interactions should be added for capillary waves. That evolution is strongly affected by the presence of turbulent wind because it transfers energy to the waves. The growth rate of wind waves was calculated by Miles in 1957 on the basis of the weak air-water coupling. His formula involves the solution of the hydrodynamic Rayleigh equation at the critical level, which is the height at which the phase speed of the wave is equal to the wind speed. We develop an efficient numerical scheme to compute it and then compare the theory with the observational data compiled by Plant. We eventually propose asymptotic solutions of the Rayleigh equation for a generic wind profile, which will be useful to get a better understanding of the experimental results.
|
|
