| 1. |
|
|
| 2. |
- Alström, Per, et al.
(författare)
-
A review of the recent advances in the systematics of the avian superfamily Sylvioidea
- 2013
-
Ingår i: Chinese Birds. - : Chinese Birds (Press). - 1674-7674. ; 4, s. 99-131
-
Tidskriftsartikel (refereegranskat)abstract
- The systematics of the avian superfamily Sylvioidea are reviewed, focusing on studies of relationships among families and within genera, more superficially on taxonomic studies at the species level. For the families Bernieridae and Phylloscopidae, new analyses based on already published sequence data are presented. Our understanding of relationships has been vastly improved in recent years due to a large number of molecular studies. However, the relationships among the different families remain largely obscured, probably mainly as a result of rapid divergence of the different primary lineages (families). Also, species level taxonomy has been much improved in recent years due to a large number of studies applying molecular markers and/or vocalizations and other life-history data. It seems likely that the number of species will continue to increase, as new groups are being studied with modern integrative methods.
|
|
| 3. |
- Alström, Per, et al.
(författare)
-
Integrative taxonomy of the Plain-backed Thrush (Zoothera mollissima) complex (Aves, Turdidae) reveals cryptic species, including a new species.
- 2016
-
Ingår i: Avian research. - : Elsevier BV. - 2053-7166. ; 7:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly sympatric. Methods: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic (two mito- chondrial and two nuclear markers), ecological and distributional datasets. Results: In earlier field observations, we noted two very different song types of“Plain-backed”Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China (“Alpine Thrush”); a forest breeder in the eastern Himalayas and northwest Yunnan (at least), China (“Himalayan Forest Thrush”); and a forest breeder in central Sichuan (“Sichuan Forest Thrush”). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is prob- ably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists (“Yunnan Thrush”). However, we find no consistent morphological differences from Alpine Thrush, and its breed- ing range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative “Yunnan Thrush” as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato (s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocin- cla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto (s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest Thrush. Conclusions: The Plain-backed Thrush Z. mollissima s.l. comprises at least three species: Alpine Thrush Z. mollissima s.s., with a widespread alpine breeding distribution; Sichuan Forest Thrush Z. griseiceps, breeding in central Sichuan forests; and Himalayan Forest Thrush, breeding in the eastern Himalayas and northwest Yunnan (at least), which is described herein as a new species. “Yunnan Thrush” requires further study.
|
|
| 4. |
- Alström, Per, et al.
(författare)
-
Multiple species within the Striated Prinia Prinia crinigera-Brown Prinia P. polychroa complex revealed through an integrative taxonomic approach
- 2020
-
Ingår i: Ibis. - : Wiley. - 0019-1019 .- 1474-919X. ; 162:3, s. 936-967
-
Tidskriftsartikel (refereegranskat)abstract
- We re-evaluated the taxonomy of the Striated Prinia Prinia crinigera-Brown Prinia P. polychroa complex using molecular, morphological and vocal analyses. The extensive seasonal, sexual, age-related, geographical and taxon-specific variation in this complex has never before been adequately studied. As no previous genetic or vocal analyses have focused on this group, misinterpretation of taxonomic signals from limited conventional morphological study alone was likely. Using mitochondrial and nuclear DNA, we found that P. crinigera sensu lato (s.l.) comprises two non-sister groups of taxa (Himalayan crinigera and Chinese striata groups) that differ substantially morphologically and vocally and that are broadly sympatric in Yunnan Province, China. Prinia polychroa cooki (Myanmar) and P. p. rocki (southern Vietnam) are each morphologically, vocally and genetically distinct. Thai, Cambodian and Laotian populations formerly ascribed to P. p. cooki are morphologically and vocally most similar to and most closely related to Javan P. p. polychroa, and require a new name, proposed here. Prinia p. bangsi of Yunnan is part of the crinigera group rather than of P. polychroa, and hence there is no evidence for sympatry between P. polychroa s.l. and P. crinigera s.l., nor of the occurrence of P. polychroa in mainland China or Taiwan. We recommend the recognition of five species in the complex, with the following suggestions for new English names: Himalayan Prinia P. crinigera sensu stricto (s.s.; with subspecies striatula, crinigera, yunnanensis and bangsi); Chinese Prinia P. striata (subspecies catharia, parumstriata and striata); Burmese Prinia P. cooki (monotypic); Annam Prinia P. rocki (monotypic) and Deignan's Prinia P. polychroa s.s. (subspecies Javan polychroa and the new Southeast Asian taxon). This study underlines the importance of using multiple datasets for the elucidation of diversity of cryptic bird species and their evolutionary history and biogeography.
|
|
| 5. |
- Alström, Per
(författare)
-
Mångfald – ett myller av arter
- 2010
-
Ingår i: Biodiverse. - 1401-5064. ; 15, s. 3-3
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
|
| 6. |
- Alström, Per
(författare)
-
Ordning i klassen! Taxonomi & systematik - exempel från fåglarnas värld (del 1)
- 2014
-
Ingår i: Fauna och flora. - 0014-8903. ; 109, s. 28-41
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Vad är en art? Varför betraktar somliga nordlig och sydlig gulärla som olika arter, medan andraklassificerar dem som samma art? Varför skiljer sig artantalet så mycket mellan olika listor övervärldens fågelarter, och vilken lista är rätt? Varför byter vissa arter släkte, och hur kommer detsig att vissa släkten omfattar många arter medan andra bara består av en enda art? Är falkarverkligen närmare släkt med tättingar än med hökar? Kan DNA-analyser besvara alla frågor?
|
|
| 7. |
|
|
| 8. |
- André, Benny, et al.
(författare)
-
Friction and contact resistance of nanocomposite Ti-Ni-C coatings
- 2011
-
Ingår i: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 270:9-10, s. 555-566
-
Tidskriftsartikel (refereegranskat)abstract
- Ceramic nanocomposite coatings in the Ti-Ni-C were deposited using PVD and studied with respect to tribological properties and contact resistance. It was shown that coatings could be deposited combining of a low contact resistance and a low friction coefficient against silver, making them suitable for use in high performance electrical contacts.Nine coatings with different amounts of C and Ni were deposited. Coatings on flat Ni plated copper substrates were tested in a tribological ball-on-disc setup against ball bearing steel balls. Depending on primarily the amount of carbon the coatings showed very different friction coefficient and wear rate. The coatings were also deposited on cylindrical Ni plated copper substrates. Using geometrically identical silver plated cylinders as counter surface these were evaluated in a test setup better resembling a real life electrical contact. For most coatings a low electrical contact resistance was measured. The evolution of friction coefficient and contact resistance was correlated to wear marks and contact tracks, with their generated tribofilms, as examined after testing using electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy.
|
|
| 9. |
- Chen, Huijing, et al.
(författare)
-
Multimodal imaging in the differential diagnosis of glioma recurrence from treatment-related effects : A protocol for systematic review and network meta-analysis
- 2021
-
Ingår i: NANOMEDICINE AND NEUROPROTECTION IN BRAIN DISEASES. - : ELSEVIER ACADEMIC PRESS INC. - 9780323901628 ; , s. 377-383
-
Bokkapitel (refereegranskat)abstract
- Background: Glioma is the most common malignant primary brain tumor and it will always recur. To date, various multimodal imaging including magnetic resonance imaging (MRI) and positron emission tomography computed tomography (PET/CT) was used to differentiate the diagnosis of true tumor recurrent (TuR) and treatment-related effects (TrE) in glioma patient but with no overall conclusion. In this study, SROC curve and Bayesian network meta-analysis will be used to conduct a comprehensive analysis of the results of different clinical reports, and assess the efficacy of multimodal imaging in difference TuR and TrE. Methods: To find more comprehensive information about the application of multimodal imaging in glioma patients, we searched the EMBASE, Pubmed, and Cochrane Central Register of Controlled Trials for relevant clinical trials. We also reviewed their reference lists to avoid omissions. QUADAS-2, RevMan software, Stata, and R software will be used. Results: This study will provide reliable evidence for the efficacy of multimodal imaging in the differential diagnosis of TuR and TrE in glioma patients. Conclusion: We will evaluate the effectiveness of different and rank each imaging method in glioma patients to provide a decision-making reference on which method to choose for clinicians.
|
|
| 10. |
- Dahlgren, Peter, 1963
(författare)
-
Switch-Level Fault Simulation Based on Local Algorithms
- 1995
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The presence of realistic faults in CMOS networks, such as shorts and opens, frequently gives rise to intermediate voltage values. At the switch level, these values result in undetermined logic states (X) which are likely to propagate to the outputs, causing uncertainty in the estimation of test set efficiency. The first part of this thesis presents event-driven switch-level algorithms for handling abnormal situations occurring in networks in the presence of faults. A proposal is made for an extension to the traditional single-dominance node model which efficiently solves conflicts that may occur between adjacent nodes assigned the X state and thereby significantly reduces the spread of X values as compared with traditional methods. The degradation of confidence in fault detection measures owing to undetermined output values is discussed. A new switch-level model is presented which allows an arbitrary number of dominant signals associated with the state of a node. The strength of several signal contributions can thereby be taken into account when the logic state is computed. It is shown that the error bounds in the voltage prediction, in many cases, are significantly reduced in comparison with traditional models. An efficient two-pass fault simulation algorithm is presented which, during the first pass, simulates the entire network with a less sophisticated node model and detects any faulty situations in a subnetwork. Second, this subnetwork is evaluated under the proposed multiple-dominance node model. The second part of this thesis deals with the modeling of particle-induced transients in combinational networks and includes results from physical fault injection experiments. A novel technique is presented for determining the relative frequency of Single Event Upsets (SEUs) originating from combinational logic and direct hits in latches. A new switch-level algorithm is proposed for the simulation of transients in combinational networks in which a first-order RC model is applied to the fault injection node for predicting the width of a voltage pulse. The fact that transients may fade out during propagation is efficiently modeled by taking into account the pulse width and the topology of subsequent transistor stages.
|
|
