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1.
Forensic Sci Int Genet ; 29: 145-153, 2017 07.
Article in English | MEDLINE | ID: mdl-28441635

ABSTRACT

Searching a national DNA database with complex and incomplete profiles usually yields very large numbers of possible matches that can present many candidate suspects to be further investigated by the forensic scientist and/or police. Current practice in most forensic laboratories consists of ordering these 'hits' based on the number of matching alleles with the searched profile. Thus, candidate profiles that share the same number of matching alleles are not differentiated and due to the lack of other ranking criteria for the candidate list it may be difficult to discern a true match from the false positives or notice that all candidates are in fact false positives. SmartRank was developed to put forward only relevant candidates and rank them accordingly. The SmartRank software computes a likelihood ratio (LR) for the searched profile and each profile in the DNA database and ranks database entries above a defined LR threshold according to the calculated LR. In this study, we examined for mixed DNA profiles of variable complexity whether the true donors are retrieved, what the number of false positives above an LR threshold is and the ranking position of the true donors. Using 343 mixed DNA profiles over 750 SmartRank searches were performed. In addition, the performance of SmartRank and CODIS were compared regarding DNA database searches and SmartRank was found complementary to CODIS. We also describe the applicable domain of SmartRank and provide guidelines. The SmartRank software is open-source and freely available. Using the best practice guidelines, SmartRank enables obtaining investigative leads in criminal cases lacking a suspect.


Subject(s)
DNA Fingerprinting , Databases, Nucleic Acid , Likelihood Functions , Software , Forensic Genetics , Humans
2.
J Phys Condens Matter ; 28(42): 425701, 2016 10 26.
Article in English | MEDLINE | ID: mdl-27541966

ABSTRACT

Small-angle neutron scattering on high quality single crystalline Ba1-x K x Fe2As2 reveals the transition from a low-field vortex solid phase with orientational order to a vortex polycrystal at high magnetic field. The vortex order-disorder transition is correlated with the second-peak feature in isothermal hysteresis loops, and is interpreted in terms of the generation of supplementary vortex solid dislocations. The sharp drop of the structure factor above the second peak field is explained by the dynamics of freezing of the vortex ensemble in the high field phase.

3.
Phys Rev Lett ; 114(6): 067003, 2015 Feb 13.
Article in English | MEDLINE | ID: mdl-25723240

ABSTRACT

Despite extensive work on high-temperature superconductors, the critical behavior of an incipient condensate has so far been studied exclusively under equilibrium conditions. Here, we excite Bi(2)Sr(2)CaCu(2)O(8+δ) with a femtosecond laser pulse and monitor the subsequent nonequilibrium dynamics of the midinfrared conductivity. Our data allow us to discriminate temperature regimes where superconductivity is either coherent, fluctuating or vanishingly small. Above the transition temperature T(c), we make the striking observation that the relaxation to equilibrium exhibits power-law dynamics and scaling behavior, both for optimally and underdoped superconductors. Our findings can in part be modeled using time-dependent Ginzburg-Landau theory, and they provide strong indication of universality in systems far from equilibrium.

4.
Phys Rev Lett ; 105(4): 047001, 2010 Jul 23.
Article in English | MEDLINE | ID: mdl-20867876

ABSTRACT

The field-driven transition from an ordered Bragg glass to a disordered vortex phase in single-crystalline MgB2 is tuned by an increasing density of point defects, introduced by electron irradiation. The discontinuity observed in magnetization attests to the first-order nature of the transition. The temperature and defect density dependences of the transition field point to vortex pinning mediated by fluctuations in the quasiparticle mean free path, and reveal the mechanism of the transition in the absence of complicating factors such as layeredness or thermal fluctuations.

5.
Phys Rev Lett ; 102(20): 207001, 2009 May 22.
Article in English | MEDLINE | ID: mdl-19519062

ABSTRACT

We report high-sensitivity microwave measurements of the in-plane penetration depth lambda_{ab} and quasiparticle scattering rate 1/tau in several single crystals of the hole-doped Fe-based superconductor Ba(1-x)K(x)Fe(2)As(2) (x approximately 0.55). While a power-law temperature dependence of lambda_{ab} with a power approximately 2 is found in crystals with large 1/tau, we observe an exponential temperature dependence of the superfluid density consistent with the existence of fully opened two gaps in the cleanest crystal we studied. The difference may be a consequence of different levels of disorder inherent in the crystals. We also find a linear relation between the low-temperature scattering rate and the density of quasiparticles, which shows a clear contrast to the case of d-wave cuprate superconductors with nodes in the gap. These results demonstrate intrinsically nodeless order parameters in the Fe arsenides.

6.
Phys Rev Lett ; 99(8): 087001, 2007 Aug 24.
Article in English | MEDLINE | ID: mdl-17930974

ABSTRACT

Vortex matter in Bi(2)Sr(2)CaCu(2)O(8) with a low concentration of tilted columnar defects (CDs) was studied using magneto-optical measurements and molecular dynamics simulations. It is found that while the dynamic properties are significantly affected by tilting the magnetic field away from the CDs, the thermodynamic transitions are angle independent. The simulations indicate that vortex pancakes remain localized on the CDs even at large tilting angles. This preserves the vortex thermodynamics, while vortex pinning is considerably weakened due to kink sliding.


Subject(s)
Magnetic Fields , Thermodynamics , Alloys , Magnetics , Models, Chemical , Molecular Dynamics Simulation , Phase Transition , Point Mutation , Porosity
7.
Phys Rev Lett ; 99(25): 257001, 2007 Dec 21.
Article in English | MEDLINE | ID: mdl-18233548

ABSTRACT

A miniature Hall-sensor array was used to detect magnetic induction locally in the vortex states of the beta-pyrochlore superconductor KOs2O6. Below the first-order transition at T{p} approximately 8 K, which is associated with a change in the rattling motion of K ions, the lower critical field and the remanent magnetization both show a distinct decrease, suggesting that the electron-phonon coupling is weakened below the transition. At high magnetic fields, the local induction shows an unexpectedly large jump at T{p} whose sign changes with position inside the sample. Our results demonstrate a novel redistribution of vortices whose energy is reduced abruptly below the first-order transition at T{p}.

8.
Phys Rev Lett ; 97(23): 237005, 2006 Dec 08.
Article in English | MEDLINE | ID: mdl-17280235

ABSTRACT

Precision measurements of the vortex phase diagram in single crystals of the layered superconductor Bi2Sr2CaCu2O8+delta in oblique magnetic fields confirm the existence of a second phase transition, in addition to the usual first-order vortex-lattice melting line Hm(T). The transition has a strong first-order character, is accompanied by strong hysteresis, and intersects the melting line in a tricritical point (Hm perpendicular, Hcr parallel). Its field dependence and the changing character of the melting line at the tricritical point strongly suggest that the ground state for magnetic fields closely aligned with the superconducting layers is a lattice of uniformly tilted vortex lines.

9.
Vet Q ; 27(1): 21-9, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15835281

ABSTRACT

Quality management on dairy farms becomes more and more important regarding the different areas of animal health, animal welfare and food safety. Monitoring animals, farm conditions and farm records can be extended with risk identification and risk management. The hazard analysis critical control point's system is useful as an on farm strategy to control the product as well as the production process on the areas of animal health, animal welfare and food safety. This article deals in detail with the question how to develop a qualitative method where risk can be defined as an interaction between probability and impact. Two parts of the production process (milk harvest and treatment of cows) where used as an example how to apply the hazard analysis critical control point's system on chemical, physical and microbiological contaminants of milk. Not just only by summarizing the different critical checkpoints for each area but also by giving them a precise judgement of probability and impact.


Subject(s)
Consumer Product Safety , Dairying/standards , Food Contamination/prevention & control , Food Handling/standards , Food Inspection/methods , Milk , Animals , Dairy Products/analysis , Dairy Products/microbiology , Dairy Products/standards , Dairying/methods , Food Contamination/analysis , Food Handling/methods , Food Inspection/standards , Humans , Milk/chemistry , Milk/microbiology , Milk/standards , Quality Control , Risk Assessment , Risk Management
10.
Phys Rev Lett ; 93(9): 097002, 2004 Aug 27.
Article in English | MEDLINE | ID: mdl-15447129

ABSTRACT

Using a differential magneto-optical technique to visualize the flow of transport currents, we reveal a new delocalization line within the reversible vortex liquid region in the presence of a low density of columnar defects. This line separates a homogeneous vortex liquid, in which all the vortices are delocalized, from a heterogeneous "nanoliquid" phase, in which interconnected nanodroplets of vortex liquid are caged in the pores of a solid skeleton formed by vortices pinned on columnar defects. The nanoliquid phase displays high correlation along the columnar defects but no transverse critical current.

11.
Phys Rev Lett ; 92(3): 037005, 2004 Jan 23.
Article in English | MEDLINE | ID: mdl-14753899

ABSTRACT

The introduction of columnar defects in (K,Ba )Bi O3 single crystals shifts both the irreversibility and thermodynamic transition lines, respectively, deduced from ac susceptibility (and/or transport) and specific heat measurements, upwards. This shift can be attributed to the defect-induced decrease of the difference (Delta F) between the free energies in the superconducting and the normal states, assuming that the position of the superconducting transition is given by the condition absolute value Delta F approximately k(B )T/xi(3 ). This criterion also perfectly reproduces the influence of the angle between the tracks and the external field. This result suggests that no vortex liquid phase exists in this system.

12.
Phys Rev Lett ; 90(14): 147001, 2003 Apr 11.
Article in English | MEDLINE | ID: mdl-12731938

ABSTRACT

We present a systematic study of the topology of the vortex solid phase in superconducting Bi2Sr2CaCu2O8 samples with low doses of columnar defects. A new state of vortex matter imposed by the presence of geometrical contours associated with the random distribution of columns is found. The results show that the first-order liquid-solid transition in this vortex matter does not require a structural symmetry change.

13.
Phys Rev Lett ; 90(8): 087004, 2003 Feb 28.
Article in English | MEDLINE | ID: mdl-12633453

ABSTRACT

Bitter decoration and magneto-optical studies reveal that in heavy-ion irradiated superconductors, a "porous" vortex matter is formed when vortices outnumber columnar defects. In this state ordered vortex crystallites are embedded in the "pores" of a rigid matrix of vortices pinned on columnar defects. The crystallites melt through a first-order transition while the matrix remains solid. The melting temperature increases with density of columnar defects and eventually turns into a continuous transition. At high temperatures a sharp kink in the melting line is found, signaling an abrupt change from crystallite melting to melting of the rigid matrix.

14.
Phys Rev Lett ; 90(3): 037004, 2003 Jan 24.
Article in English | MEDLINE | ID: mdl-12570520

ABSTRACT

We have measured the specific heat, resistivity, and ac susceptibility of (K,Ba)BiO3 single crystals before and after introduction of either point or columnar defects by electron (EI) or heavy-ion irradiation (HII). While the magnetic field dependence of these properties remains mainly unaffected by EI, the irreversibility line and the location of the specific heat anomaly are both shifted up in temperature after HII. The shift is apparent only if the magnetic field is applied parallel to the ion tracks. For perpendicularly applied fields, both lines lie at the same field as in the pristine sample. These experiments call the nature of the vortex liquid state into question.

15.
Phys Rev Lett ; 86(22): 5136-9, 2001 May 28.
Article in English | MEDLINE | ID: mdl-11384440

ABSTRACT

The low-field Bose-glass transition temperature in heavy-ion irradiated Bi(2)Sr(2)CaCu(2)O(8+delta) increases progressively with increasing density n(d) of irradiation-induced columnar defects, but saturates for n(d) greater or = 1.5 x 10(9) cm(-2). The maximum Bose-glass temperature corresponds to that above which diffusion of two-dimensional pancake vortices between vortex lines becomes possible, and the "linelike" character of vortices is lost. We develop a description of the Bose-glass line that quantitatively describes experiments on crystals with widely different track densities and material parameters.

16.
Phys Rev Lett ; 86(7): 1327-30, 2001 Feb 12.
Article in English | MEDLINE | ID: mdl-11178075

ABSTRACT

We measured the heat capacity C(p) and microwave surface impedance Z(s) in the vortex state of YNi2B2C. In contrast to conventional s-wave superconductors, C(p) shows a square root[H] dependence. This square root[H] dependence persists even after the introduction of the columnar defects which change the electronic structure of the vortex core regime and destroy the regular vortex lattice. On the other hand, flux flow resistivity is nearly proportional to H. These results indicate that the vortex state of YNi2B2C is fundamentally different from the conventional s-wave counterparts, in that the delocalized quasiparticle states around the vortex core are important, similar to d-wave superconductors.

17.
Ned Tijdschr Geneeskd ; 142(12): 633-6, 1998 Mar 21.
Article in Dutch | MEDLINE | ID: mdl-9623127

ABSTRACT

The Central Medical Pharmaceutical Committee of the Health Insurance Council informs the medical profession annually about the effects of drugs through the Pharmacotherapeutical Compass. The 1998 edition now contains a chapter on pharmacokinetics as well. Compared with previous editions the main alterations of the contents concern an introduction and advice on the antidepressants, two protocols with respect to the medical treatment of patients suffering from epilepsy, advice with respect to oral drugs for the treatment of inflammatory bowel disease, an introduction and advice regarding the treatment of allergic rhinitis, the treatment of patients suffering from AIDS with antiretroviral drugs, the treatment of genital herpes, the taking of insulin lispro by patients with diabetes and the taking of bisphosphonates to prevent or to treat osteoporosis. Two corrections to the 1998 edition are given.


Subject(s)
Drug Therapy , Journalism, Medical , Acquired Immunodeficiency Syndrome/drug therapy , Diabetes Mellitus/drug therapy , Humans , Inflammatory Bowel Diseases/drug therapy , Netherlands , Osteoporosis/prevention & control , Rhinitis/drug therapy , Virus Diseases/drug therapy
20.
Urology ; 27(1): 49-52, 1986 Jan.
Article in English | MEDLINE | ID: mdl-3942021

ABSTRACT

A new method is described with which ureteral strictures are visualized by antegrade ureteroscopy. Under direct vision a catheter is manipulated through the stricture, which is then dilated. This method is especially useful in patients with a ureteroenterocutaneostomy. A patient is described in whom this technique was successful after other endoscopic techniques had failed.


Subject(s)
Endoscopy/methods , Ureteral Obstruction/therapy , Adult , Dilatation/methods , Endoscopes , Female , Humans , Ureter , Urinary Diversion
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