1. |
- Kirsebom, O. S., et al.
(author)
-
Measurement of the 2+→0+ ground-state transition in the β decay of F 20
- 2019
-
In: Physical Review C. - 2469-9985. ; 100:6
-
Journal article (peer-reviewed)abstract
- We report the first detection of the second-forbidden, nonunique, 2+→0+, ground-state transition in the β decay of F20. A low-energy, mass-separated F+20 beam produced at the IGISOL facility in Jyväskylä, Finland, was implanted in a thin carbon foil and the β spectrum measured using a magnetic transporter and a plastic-scintillator detector. The β-decay branching ratio inferred from the measurement is bβ=[0.41±0.08(stat)±0.07(sys)]×10-5 corresponding to logft=10.89(11), making this one of the strongest second-forbidden, nonunique β transitions ever measured. The experimental result is supported by shell-model calculations and has significant implications for the final evolution of stars that develop degenerate oxygen-neon cores. Using the new experimental data, we argue that the astrophysical electron-capture rate on Ne20 is now known to within better than 25% at the relevant temperatures and densities.
|
|
2. |
- Sels, S., et al.
(author)
-
Doppler and sympathetic cooling for the investigation of short-lived radioactive ions
- 2022
-
In: Physical Review Research. - 2643-1564. ; 4:3
-
Journal article (peer-reviewed)abstract
- At radioactive ion beam (RIB) facilities, ions of short-lived radionuclides are cooled and bunched in buffer-gas-filled Paul traps to improve the ion-beam quality for subsequent experiments. To deliver even colder ions, beneficial to RIB experiments' sensitivity or accuracy, we employ Doppler and sympathetic cooling in a Paul trap cooler-buncher. The improved emittance of Mg+, K+, and O2+ ion beams is demonstrated by a reduced time-of-flight spread of the extracted ion bunches with respect to room-temperature buffer-gas cooling. Cooling externally-produced hot ions with energies of at least 7 eV down to a few Kelvin is achieved in a timescale of O(100 ms) by combining a low-pressure helium background gas with laser cooling. This is sufficiently short to cool short-lived radioactive ions. As an example of this technique's use for RIB research, the mass-resolving power in a multireflection time-of-flight mass spectrometer is shown to increase by up to a factor of 4.6 with respect to buffer-gas cooling. Simulations show good agreement with the experimental results and guide further improvements and applications. These results open a path to a significant emittance improvement and, thus, unprecedented ion-beam qualities at RIB facilities, achievable with standard equipment readily available. The same method provides opportunities for future high-precision experiments with radioactive cold trapped ions.
|
|
3. |
- Lorenz, Ch, et al.
(author)
-
β Decay of 127Cd and Excited States in 127In
- 2019
-
In: Physical Review C. - 2469-9985. ; 99:4
-
Journal article (peer-reviewed)abstract
- A dedicated spectroscopic study of the β decay of 127Cd was conducted at the IGISOL facility at the University of Jyväskylä. Following high-resolution mass separation in a Penning trap, β-γ-γ coincidences were used to considerably extend the decay scheme of 127In. The β-decaying 3/2+ and 11/2- states in 127Cd have been identified with the 127Cd ground state and the 283-keV isomer. Their respective half-lives have been measured to 0.45(+12-8)s and 0.36(4) s. The experimentally observed β feeding to excited states of 127In and the decay scheme of 127In are discussed in conjunction with large-scale shell-model calculations.
|
|
4. |
|
|
5. |
- Vilen, ST, et al.
(author)
-
Intracellular co-localization of trypsin-2 and matrix metalloprotease-9: Possible proteolytic cascade of trypsin-2, MMP-9 and enterokinase in carcinoma
- 2008
-
In: Experimental Cell Research. - : Elsevier BV. - 1090-2422 .- 0014-4827. ; 314:4, s. 914-926
-
Journal article (peer-reviewed)abstract
- Tumor-associated trypsin-2 and matrix metalloprotease-9 (MMP-9) are associated with cancer, particularly with invasive squamous cell carcinomas. They require activation for catalytical competence via proteolytic cascades. One cascade is formed by enterokinase, trypsin-2 and MMP-9; enterokinase activates trypsinogen-2 to trypsin-2, which is an efficient proMMP-9 activator. We describe here that oral squamous cell carcinomas express all members of this cascade: MMP-9, trypsin-2 and enterokinase. The expression of enterokinase in a carcinoma cell line not derived from the duodenum was shown here for the first time. Enterokinase directly cleaved proMMP-9 at the Lys(65)-Ser(66) site, but failed to activate it in vitro. We demonstrated by confocal microscopy that MMP-9 and trypsin-2 co-localized in intracellular vesicles of the carcinoma cells. This co-localization of trypsin-2 and MMP-9 resulted in intracellular proMMP-9 processing that represented fully or partially activated MMP-9. However, although both proteases were present also in various bone tumor tissues, MMP-9 and trypsin-2 never co-localized at the cellular level in these tissues. This suggests that the intracellular vesicular co-localization, storage and possible activation of these proteases may be a unique feature for aggressive epithelial tumors, such as squamous cell carcinomas, but not for tumors of mesenchymal origin.
|
|
6. |
|
|
7. |
- Maastrup, Ragnhild, et al.
(author)
-
Compliance with the Baby-friendly Hospital Initiative for Neonatal Wards (Neo-BFHI) : A cross-sectional study in 36 countries
- 2019
-
In: Maternal and Child Nutrition. - : Blackwell Science Ltd.. - 1740-8695 .- 1740-8709. ; 15:2
-
Journal article (peer-reviewed)abstract
- In 2012, the Baby-friendly Hospital Initiative for Neonatal Wards (Neo-BFHI) began providing recommendations to improve breastfeeding support for preterm and ill infants. This cross-sectional survey aimed to measure compliance on a global level with the Neo-BFHI’s expanded Ten steps to Successful Breastfeeding and three Guiding Principles in neonatal wards. In 2017 the Neo-BFHI Self-Assessment questionnaire was used in 15 languages to collect data from neonatal wards of all levels of care. Answers were summarized into compliance scores ranging from 0 to 100 at the ward, country and international levels. A total of 917 neonatal wards from 36 low, middle and high-income countries from all continents participated. The median international overall score was 77, and median country overall scores ranged from 52 to 91. Guiding Principle 1 (respect for mothers), Step 5 (breastfeeding initiation and support), and Step 6 (human milk use) had the highest scores, 100, 88, and 88, respectively. Steps 3 (antenatal information) and 7 (rooming-in) had the lowest scores, 63 and 67, respectively. High-income countries had significantly higher scores for Guiding principle 2 (family-centered care), Step 4 (skin-to-skin contact) and Step 5. Neonatal wards in hospitals ever-designated Baby-friendly had significantly higher scores than those never designated. Sixty percent of managers stated they would like to obtain Neo-BFHI designation. Currently, Neo-BFHI recommendations are partly implemented in many countries. The high number of participating wards indicates international readiness to expand Baby-friendly standards to neonatal settings. Hospitals and governments should increase their efforts to better support breastfeeding in neonatal wards.
|
|
8. |
|
|
9. |
|
|
10. |
- Weghuber, D., et al.
(author)
-
A 6-month randomized, double-blind, placebo-controlled trial of weekly exenatide in adolescents with obesity
- 2020
-
In: Pediatric Obesity. - 2047-6302 .- 2047-6310. ; 15:7
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Pharmacological treatment options for adolescents with obesity are very limited. Glucagon-like-peptide-1 (GLP-1) receptor agonist could be a treatment option for adolescent obesity.OBJECTIVE: To investigate the effect of exenatide extended release on body mass index (BMI)-SDS as primary outcome, and glucose metabolism, cardiometabolic risk factors, liver steatosis, and other BMI metrics as secondary outcomes, and its safety and tolerability in adolescents with obesity.METHODS: Six-month, randomized, double-blinded, parallel, placebo-controlled clinical trial in patients (n = 44, 10-18 years, females n = 22) with BMI-SDS > 2.0 or age-adapted-BMI > 30 kg/m2 according to WHO were included. Patients received lifestyle intervention and were randomized to exenatide extended release 2 mg (n = 22) or placebo (n = 22) subcutaneous injections given once weekly. Oral glucose tolerance tests (OGTT) were conducted at the beginning and end of the intervention.RESULTS: Exenatide reduced (P < .05) BMI-SDS (-0.09; -0.18, 0.00), % BMI 95th percentile (-2.9%; -5.4, -0.3), weight (-3 kg; -5.8, -0.1), waist circumference (-3.2 cm; -5.8, -0.7), subcutaneous adipose tissue (-552 cm3 ; -989, -114), 2-hour-glucose during OGTT (-15.3 mg/dL; -27.5, -3.1), total cholesterol (11.6 mg/dL; -21.7, -1.5), and BMI (-0.83 kg/m2 ; -1.68, 0.01) without significant change in liver fat content (-1.36; -3.12, 0.4; P = .06) in comparison to placebo. Safety and tolerability profiles were comparable to placebo with the exception of mild adverse events being more frequent in exenatide-treated patients.CONCLUSIONS: Treatment of adolescents with severe obesity with extended-release exenatide is generally well tolerated and leads to a modest reduction in BMI metrics and improvement in glucose tolerance and cholesterol. The study indicates that the treatment provides additional beneficial effects beyond BMI reduction for the patient group.
|
|
11. |
|
|
12. |
- Gao, Zhihao, et al.
(author)
-
Benchmark of a multi-physics Monte Carlo simulation of an ionguide for neutron-induced fission products
- 2022
-
In: European Physical Journal. - : Springer Nature. - 1286-0042 .- 1286-0050. ; 58:2
-
Journal article (peer-reviewed)abstract
- To enhance the production of medium-heavy,neutron-rich nuclei, and to facilitate measurements of independentyields of neutron-induced fission, a proton-toneutronconverter and a dedicated ion guide for neutroninducedfission have been developed for the IGISOL facilityat the University of Jyväskylä. The ion guide holds thefissionable targets, and the fission products emerging fromthe targets are collected in helium gas and transported to thedownstream experimental stations.Acomputer model, basedon a combination of MCNPX for modeling the neutron production,the fission code GEF, and GEANT4 for the transportof the fission products, was developed. The model willbe used to improve the setup with respect to the productionand collection of fission products. In this paper we benchmarkthe model by comparing simulations to a measurementin which fission products were implanted in foils located atdifferent positions in the ion guide. In addition, the productsfrom neutron activation in the titanium foil and the uraniumtargets are studied. The result suggests that the neutron fluxat the high-energy part of the neutron spectrum is overestimatedby approximately 40%.However, the transportation offission products in the uranium targets agrees with the experimentwithin 10%. Furthermore, the simulated transportationof fission products in the helium gas achieves almost perfectagreement with the measurement. Hence, we conclude thatthe model, after correction for the neutron flux, is well suitedfor optimization studies of future ion guide designs.
|
|
13. |
- Gao, Zhihao, et al.
(author)
-
Fission studies at IGISOL/JYFLTRAP : Simulations of the ion guide for neutron-induced fission and comparison with experimental data
- 2020
-
In: ND 2019. - : EDP Sciences. - 9782759891061
-
Conference paper (peer-reviewed)abstract
- For the production of exotic nuclei at the IGISOL facility, an ion guide for neutron-induced fission has been developed and tested in experiments. Fission fragments are produced inside the ion guide and collected using a helium buffer gas. Meanwhile, a GEANT4 model has been developed to simulate the transportation and stopping of the charged fission products. In a recent measurement of neutron-induced fission yields, implantation foils were located at different positions in the ion guide. The gamma spectra from these foils and the fission targets are compared to the results from the GEANT4 simulation.In order to allow fission yield measurements in the low yield regions, towards the tails and in the symmetric part of the mass distribution, the stopping and extraction efficiency of the ion guide has to be significantly improved. This objective can be achieved by increasing the size while introducing electric field guidance using a combination of static electrodes and an RF-carpet. To this end, the GEANT4 model is used to optimise the design of such an ion guide.
|
|
14. |
- Rakopoulos, Vasileios, et al.
(author)
-
First isomeric yield ratio measurements by direct ion counting and implications for the angular momentum of the primary fission fragments
- 2018
-
In: Physical Review C. - : AMER PHYSICAL SOC. - 2469-9985 .- 2469-9993. ; 98:2
-
Journal article (peer-reviewed)abstract
- We report the first experimental determination of independent isomeric yield ratios using direct ion counting with a Penning trap, which offered such a high resolution in mass that isomeric states could be separated. The measurements were performed at the Ion Guide Isotope Separator On-Line (IGISOL) facility at the University of Jyvaskyla. The isomer production ratios of Ge-81, Y-96,Y-97 Sn-128(,1)30, and Sb-129 in the 25-MeV proton-induced fission of U-na(t) and Th-232 were studied. Three isomeric pairs (Ge-81, Y-96, and Sb-129) were measured for the first time for the U-na(t)(p, f) reaction, while all the reported yield ratios for the Th-232(p, f) reaction were determined for the first time. The comparison of the experimentally determined isomeric yield ratios with data available in the literature shows a reasonable agreement, except for the case of Sn-130 for unspecified reasons. The obtained results were also compared with the GEF model, where good agreement can be noticed in most cases for both reactions. Serious discrepancies can only be observed for the cases of Y-96(,)97 for both reactions. Moreover, based on the isomeric yield ratios, the root-mean-square angular momenta (J(r)(ms)) of the fission fragments after scission were estimated using the TALYS code. The experimentally determined isomeric yield ratios, and consequently the deduced J(rms), for Sn-130 are significantly lower compared to Sn-128 for both fissioning systems. This can be attributed to the more spherical shape of the fragments that contribute to the formation of Sn-130, due to their proximity to the N = 82 shell closure. The values of J(rms) for Sb-129 are higher than Sn-128 for both reactions, despite the same neutron number of both nuclides (N = 78), indicating the odd-Z effect where fission fragments with odd-Z number tend to bear larger angular momentum than even-Z fragments. The isomer production ratio for the isotopes of Sn is more enhanced in the U-na(t)(p, f) reaction than in Th-232(p, f). The opposite is observed for Y-96 and Y-97. These discrepancies might be associated to different scission shapes of the fragments for the two fission reactions, indicating the impact that the different fission modes can have on the isomeric yield ratios.
|
|
15. |
- Roslin, Tomas, et al.
(author)
-
A molecular-based identification resource for the arthropods of Finland
- 2022
-
In: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 22:2, s. 803-822
-
Journal article (peer-reviewed)abstract
- To associate specimens identified by molecular characters to other biological knowledge, we need reference sequences annotated by Linnaean taxonomy. In this study, we (1) report the creation of a comprehensive reference library of DNA barcodes for the arthropods of an entire country (Finland), (2) publish this library, and (3) deliver a new identification tool for insects and spiders, as based on this resource. The reference library contains mtDNA COI barcodes for 11,275 (43%) of 26,437 arthropod species known from Finland, including 10,811 (45%) of 23,956 insect species. To quantify the improvement in identification accuracy enabled by the current reference library, we ran 1000 Finnish insect and spider species through the Barcode of Life Data system (BOLD) identification engine. Of these, 91% were correctly assigned to a unique species when compared to the new reference library alone, 85% were correctly identified when compared to BOLD with the new material included, and 75% with the new material excluded. To capitalize on this resource, we used the new reference material to train a probabilistic taxonomic assignment tool, FinPROTAX, scoring high success. For the full-length barcode region, the accuracy of taxonomic assignments at the level of classes, orders, families, subfamilies, tribes, genera, and species reached 99.9%, 99.9%, 99.8%, 99.7%, 99.4%, 96.8%, and 88.5%, respectively. The FinBOL arthropod reference library and FinPROTAX are available through the Finnish Biodiversity Information Facility (www.laji.fi) at https://laji.fi/en/theme/protax. Overall, the FinBOL investment represents a massive capacity-transfer from the taxonomic community of Finland to all sectors of society.
|
|
16. |
|
|
17. |
- Turesson, Ingemar, et al.
(author)
-
Intensive chemotherapy in patients with chronic myelogenous leukaemia (CML) in accelerated or blastic phase - a report from the Swedish CML Group
- 2002
-
In: British Journal of Haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 118, s. 1048-
-
Journal article (peer-reviewed)abstract
- In attempting to restore the chronic phase (CP) of chronic myelogenous leukaemia (CML), the Swedish CML group utilized an intensive chemotherapy protocol for 83 patients (aged 16-79 years) in accelerated (AP, n = 22) or blastic phase (BC, n = 61). Most patients received a combination of mitoxantrone (12 mg/m(2) /d) and etoposide (100 mg/m(2) /d) together with cytosine arabinoside (1 g/m(2) b.i.d) for 4 d. Overall, 39 patients (47%) achieved a second CP (CP2)/partial remission (PR). Responding patients < 65 years were eligible for ablative chemotherapy followed by an allogeneic (SCT) or a double autologous stem cell transplant (ASCT). Seventeen of 34 responders < 65 years failed to proceed to transplantation as a result of early disease progression (n = 15) or disease-related complications (n = 2). The remaining 17 patients underwent SCT (n = 9; including four unrelated donor SCT) or ASCT (n = 8). Only one of the eight ASCT patients had a second ASCT; the remaining seven failed because of progression (n = 5) or hypoplasia (n = 2). The median duration of CP2/PR was 6 months (range 1-72 months). Five patients achieved a longer CP2/PR than CP1. The 1 year survival was 70% for SCT/ASCT patients (median survival 21 months), 50% for responding patients overall, but only 7% for non-responders (P < 0.001). Three SCT/ASCT patients are long-term survivors (65+, 66+ and 73+ months). In conclusion, approximately half of the patients achieved a CP2/PR after intensive chemotherapy, with a clear survival advantage for responders vs non-responders. Subsequent SCT/ASCT was feasible for half of the responders (< 65 years), and one individual underwent double ASCT. Novel therapeutic options for CML patients in AP/BP are needed.
|
|