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Neural activity preceding an event can influence subsequent memory formation, yet the precise cortical dynamics underlying this activity and the associated cognitive states remain unknown. We investigate these questions here by examining intracranial EEG recordings as 28 participants with electrodes placed for seizure monitoring participated in a verbal paired-associates memory task. We found that, preceding successfully remembered word pairs, an orientation cue triggered a low-frequency 2–4 Hz phase reset in the right temporoparietal junction with concurrent increases in low-frequency power across cortical regions that included the prefrontal cortex and left temporal lobe. Regions that exhibited a significant increase in 2–4 Hz power were functionally bound together through progressive low-frequency 2–4 Hz phase synchrony. Our data suggest that the interaction between power and phase synchrony reflects the engagement of attentional networks that in large part determine the extent to which memories are successfully encoded.SIGNIFICANCE STATEMENTHere we investigate the spatiotemporal cortical dynamics that precede successful memory encoding. Using intracranial EEG, we observed significant changes in oscillatory power, intertrial phase consistency, and pairwise phase synchrony that predict successful encoding. Our data suggest that the interaction between power and phase synchrony reflects the engagement of attentional networks that in large part determine the extent to which memories are successfully encoded.

The projection of neuronal processes is guided by a variety of soluble and insoluble factors, which are sensed by a fiber’s growth cone. It is the differential distribution of such guidance cues that determine the direction in which neurites grow. The growth cone senses these cues on a fine scale, using extensible filopodia that range from a few to tens of µm in length. In order to study the effects of guidance cues on spiral ganglion (SG) neurites, we have used methods for distributing both soluble and insoluble cues on a scale appropriate for sensing by growth filopodia. The scale of these methods are at the micro, rather than nano, level to match the sensing range of the growth cone. Microfluidics and transfected cells were used to spatially localize tropic factors within the fluid environment of extending neurites. Micropatterning was used to present neurites with stripes of insoluble factors. The results indicate that differentially distributed permissive, repulsive and stop signals can control the projection of SG neurites. Implications for future micropatterning studies, for SG development and for the growth of deafferented SG dendrites toward a cochlear implant are discussed.

Daten aus konservativen erkennungsdienstlichen Masnahmen konnen ohne Richtervorbehalt auch bei minder schweren Straftaten erhoben und gespeichert werden. Hierbei werden Personaldaten und auserlich erkennbare Merkmale dokumentiert. Obligate Fotos lassen ethnische Zugehorigkeiten, Korperbautypen und Krankheitssymptome zu erkennen. Die Daktyloskopie liefert mit Hilfe der „Dermatoglyphic-Methode“ ebenfalls Hinweise auf schwere Erbleiden (Down-Syndrom u.v.a.m). Mit dem DNS-Identifizierungsmuster werden 8 nichtkodierende autosomale Lozi und das Kerngeschlecht am Amelogeninort bestimmt. Insgesamt offenbart das DNS-Identifizierungsmuster wesentlich weniger personlichkeitsrelevante Informationen als die anderen Methoden. Der Eingriff in die Personlichkeit ist bei den konservativen Masnahmen wesentlich groser. Es gibt keine Argumente fur eine juristische Ungleichbehandlung der verschiedenen erkennungsdienstlichen Masnahmen, sowohl in Bezug auf den Richtervorbehalt als auch auf den Straftatenkatalog. Allerdings muss das Probenvernichtungsgebot kontrollierbar eingehalten werden.

We present the design of a chamber to evaluate in vitro how species and concentrations of soluble molecules control features of cell growth-potentially including cell proliferation, cell motility, process extension, and process termination. We have created a reusable cell culture plate that integrates a microfluidic media delivery network with standard cell culture environment. The microfluidic network delivers a stream of cell culture media with a step-like concentration gradient down a 50-100 microm wide microchannel called the presentation region. Migrating cells or growing cell processes freely choose between the two distinct chemical environments in the presentation region, but they are forced to exclusively choose either one environment or the other when they grow past a physical barrier acting as a decision point. Our fabrication technique requires little specialized equipment, and can be carried out in approximately 4 days per plate. We demonstrate the effectiveness of our plates as neurites from spiral ganglion explants preferentially grow in media containing neurotrophin-3 (NT-3) as opposed to media without NT-3. Our design could be used without modification to study dissociated cell responses to soluble growth cues, and for behavioral screening of small motile organisms.

Following the introduction of limit values for blood alcohol and breath alcohol concentrations of 0.5 g/kg and 0.25 mg/L, respectively, as provided under s. 24 a of the German Road Traffic Act the question is whether also breath alcohol concentrations can be back calculated to the time of the traffic offence in cases where it is definite that the person to be examined is in the period of alcohol elimination. To this end, a study was performed in which 56 healthy volunteers consumed 0.5, 0.8 and 1.0 g of ethanol mixed with fruit juice per kilogram of body weight over a period of 10–20 min. Calculations included all 391 pairs of concurrent blood alcohol and breath alcohol concentration values obtained after 2 h following the end of drinking. All volunteers exceeded the peak value of the alcohol curve. The measured values included were above 0.1 g/kg and 0.05 mg/L. For an average intake of alcohol of 0.88 g/kg the following regression lines were calculated for the period starting 2 h after the end of drinking: blood alcohol concentration [g/kg]=1.318−0.172 h and breath alcohol concentration [mg/L]=0.589−0.079 h. Subtracting the simple standard deviation from the mean value yielded hourly degradation rates above 0.1 g/kg and above 0.05 mg/L, respectively. Subtracting two standard deviations, the values fell below this level in both cases. In fact, back calculation of breath alcohol concentrations based on 0.05 mg/h seems to be possible for traffic offences if certain conditions are complied with, such as the use of Evidential 7110, a calibrated breath alcohol analyser approved by the Federal Physical–Technical Laboratory for measuring the breath alcohol concentration.

An 34 isolierten Leichenherzen wurden Computertomographie- (CT-) und Magnetresonanztomographie- (MRT-) Befunde mit pathologisch-anatomischen Befunden und postmortalen Veranderungen verglichen. Innere Totenflecke und postmortale Gerinnselbildungen waren in der MRT, beginnende Faulnis durch die Darstellung kleiner Gasblasen in der CT gut zu diagnostizieren. Kardiale Verkalkungen der Klappen, der Koronarien und der Papillarmuskeln konnten computertomographisch in ihrem Befallsmuster exakt lokalisiert werden. Ein Septuminfarkt zeigte sich sehr deutlich im T2-gewichteten MR-Bild. Die kollagenen Myokardnarbenareale konnten durch die von ihrer Zusammensetzung abhangigen Kontrastierungen in der T2-Wichtung veranschaulicht werden. Morphologische Veranderungen, wie Hypertrophie und Dilatation, waren sehr deutlich in ihrem Ausmas auch in der postmortalen Bildgebung zu beurteilen. Die virtuell und real gemessenen Kammerwandstarken stimmten uberein. Ein verkalkter Venenbypass mit Thrombosierung war erkennbar. Lediglich eine agonale intramurale Blutung fiel in der primaren postmortalen radiologischen Diagnostik aufgrund nur sehr dezenter Kontraste nicht auf. Insgesamt zeigte sich eine sehr gute Ubereinstimmung der radiologischen Befunde mit den histologisch bestatigten Sektionsdiagnosen.

The incorporation of reference DNA is crucial to the validation of any DNA typing protocol. This paper aims to provide a panel of reference DNAs for actual forensic profiling strategies, i.e. autosomal and gonosomal STR typing as well as mtDNA sequencing. We have characterised three human lymphoid cell lines, GM9947, GM9948 and GM3657, and considered 58 autosomal and gonosomal microsatellites as well as the mitochondrial control region sequence. Well-established markers and STRs recently developed for forensic use were involved. K562 DNA samples which we purchased from two different suppliers were also analysed. They revealed conflicting results with regard to the ChrX STR marker genotype. Hence, we suggest that K562 is no longer used for the calibration of profiling techniques. Our investigation establishes a panel of one female and two male DNA samples as an STR allelic ladder calibration tool and offers information on six alleles of each autosome (AS) marker, three alleles of each X chromosome (ChrX) marker and two alleles of each ChrY marker. In addition, sequences of the mitochondrial control region of the three DNAs are communicated in order to provide sequencing quality control.

Over the past decade investigations of human mitochondrial DNA (mtDNA) have considerably contributed to our knowledge about human evolution and migration. The genome of the Icelandic population is of special interest since Iceland has been genetically isolated for centuries. The sequence of the hypervariable regions HVS-I and HVS-II of the mtDNA control region was generated for 100 Icelandic individuals. A total of 75 different mtDNA sequences were observed, of which 19 sequences were shared by more than one individual, 16 sequences were shared by two individuals and two sequences were shared by three individuals; the most frequent haplotype (16129 A, 16239 T, 00263 G and 00315.1 C) was found six times. Both the genetic diversity (0.9925+/-0.0031) and the average number of pairwise nucleotide differences (7.371) were comparable with most of the other European populations. However, we found a smaller number of distinct mitochondrial lineages, suggesting that founder effects and genetic drift may have exerted a visible influence on the Icelandic genetic diversity. We compared these data with 1400 other European sequences from the D-Loop-BASE database. The paper discusses the evolutionary relationship between Icelandic and Central European mtDNA under due consideration of the historical context. Finally, our study has been aimed at increasing the number of mtDNA sequences available throughout the world and contributing to human genome investigations.

At the 18th Stain workshop held in Magdeburg in 1998, 15 university institutes of forensic medicine from Germany, Austria and Switzerland agreed to establish a Central European database of forensically secured mitochondrial DNA (mtDNA) sequences as a common project at the Magdeburg institute. Since then, more than 1600 sequences have been included into the D-Loop-BASE data stock which is now a profound basis for both frequency inquiries for expert opinions and scientific investigations into population genetic matters. Due to the consent agreement signed by the institutes involved, it was not possible in the beginning to access the data via the Internet, which made it difficult for all parties interested to use this database. Among the number of mtDNA databases in the Internet, there has been only one to date offering access to its data which, however, could be used for forensic purposes only to a limited extent. Together with the Institute of Technical Information Systems at the Magdeburg Otto-von-Guericke-University and the database administration, an Internet interface was developed which is available now under www.d-loop-base.de. Online inquiries for both the frequency of individual sequences and biostatistical parameters are possible now. But individual sequences will not be published. This paper shows the opportunities and limits of data inquiries.

We examined the mitochondrial (mt) loci nt00073 and nt16519 which show a considerable variability among European populations. These polymorphisms are easily detectable by means of PCR-based RFLP analysis. The study was also aimed at establishing the Light Cycler™ technique for application to forensic mt analysis. In analysing the loci nt00073 and nt16519, both methods provide very easy access and yield compatible results. We found that nt00073 is highly variable in German and Syrian populations and fairly homogeneous among Vietnamese, Japanese, Peruvians and Cameroonians. Locus nt16519 is highly variable in all populations investigated. However, in contrast to nt00073, its contribution to the mitochondrial potential for discriminating between various ethnic populations is rather negligible.

Degenerative Veranderungen machten bei einer 69 Jahre alten Frau den Ersatz eines kunstlichen Huftgelenks notwendig. Eine Verletzung der V. iliaca externa wahrend der Operation fuhrte zum Tode. Mittels Spiral-Computertomographie und nachfolgendem “volume rendering” konnte das mazerierte Praparat, bestehend aus Beckenknochen und implantierten Materialien, zerstorungsfrei, beweisfahig und jederzeit reproduzierbar dargestellt werden. Das durch Stereolithographie angefertigte originalgetreue Plastikmodell kann, frei von hygienischen und insbesondere ethischen Bedenken, ggf. auch in einem gerichtlichen Verfahren als gegenstandliches Beweismittel dienen.

Nach einem Leichenfund im Wald wurde uberpruft, ob Pilzsporen im Nasen-Rachen-Raum ahnlich wie Blutenpollen geeignet sind, Aussagen zur Todeszeit oder zum Sterbeort zu treffen. In der Spulflussigkeit der Nasenhohle einer Leiche fanden sich zahlreiche Sporen, die sich morphologisch und in ihrem chemischen Farbeverhalten den am Leichenfundort wachsenden Falschen Pfifferlingen (Hygrophoropsis aurantiaca) eindeutig zuordnen liesen. Damit konnte auch die prinzipielle Moglichkeit erschlossen werden, Pilzsporen bei Kenntnis von Vegetationszeit und Vorkommen der infrage kommenden Pilze in Erganzung anderer Methoden zur Eingrenzung der Todeszeit zu nutzen.

Sequencing of mtDNA is an advanced method for the individualisation of traces. Disadvantages of this method are expensive and time-consuming analysis and evaluation procedures as well as the necessary stock of population-genetic data which is still insufficient. Central European institutes of forensic medicine from Germany, Austria, and Switzerland have been working together since the beginning of 1998 to establish a mtDNA database. The aim is to build up a large stock of forensically established data and provide population-genetic data for frequency investigations, which will serve as a basis for expert opinions and scientific research. Good data quality is ensured by using original sequences only. Ring tests, which have been conducted to enhance analytical reliability, revealed a high correspondence rate of the analytical results obtained by the individual member institutes. Today 1410 sequences are available for comparison, of which 1285 sequences in the HV1 and HV2 regions cover the full ranges from 16051 to 16365 and from 73 to 340 (according to Anderson). The major part is formed by Central European sequences comprising 1256 data sets from Germany, Austria, and Switzerland. Today the database contains sequences from a total of 12 European, six African and three Asian countries including 100 sequences from Japan. This paper is aimed at discussing the individualisation potentials of mtDNA as well as the possibilities and limits of ethnic differentiation by means of pairwise sequence differences on the basis of the data stock available.

The mitochondrial control region includes three so-called hypervariable (HV) regions, in which the polymorphic positions show a particularly high frequency. According to a population study of 200 unrelated individuals from Germany, HVI (positions 16,024-16,365, according to Anderson) showed 88 variable positions in a total length of 342 bp (26%) and HVII (positions 73-340) displayed 65 mutable sites in 268 bp (24%). HVIII (positions 438-574) exhibited a slightly lower variability, with 25 polymorphic sites within 137 bp (18%), but contrasted clearly with the background, which showed variability rates of only 7% (positions 16,366-16,569, 1-72) and 3% (positions 341-437), respectively. At present, the displacement (D)-loop database in Magdeburg comprises 904 sequences of the mitochondrial HVI region and HVII region from Germans, Austrians and Swiss. By means of this material, the extent to which the mtDNA sequences that do not differ in the HVI and HVII regions can be differentiated by additionally sequencing HVIII was investigated.

Mit dem Alcotest 7110 Evidential MK III, durch die PTB in Braunschweig zugelassen und geeicht, steht ein hochwertiges Geratesystem zur Messung der Alkoholkonzentration in der Ausatemluft zur Verfugung. Der Umrechnungsfaktor von Atem- in Blutalkoholkonzentrationen wurde von Schoknecht [17] im Gutachten des Bundesgesundheitsamtes 1992 experimentell als BAK/AAK-Quotient mit 2,098 ±0,11 bestimmt und auf 2,1 gerundet. Der Mittelwert von 455 zeitgleichen Wertepaaren der vorliegenden Arbeit lag bei 2,2. Der Maximalwert betrug 3,29, der Minimalwert 0,74. Die Streubreite stimmte im Wesentlichen mit den theoretischen Berechnungen von Wehner et al. [19] uberein. Die gefundenen Quotienten waren theoretisch als Umrechnungsfaktoren von AAK in BAK denkbar. Aufgrund der sehr grosen Variabilitat sollte aber grundsatzlich in forensischen Gutachten eine Transformation von AAK in BAK und umgekehrt nicht erfolgen. Demzufolge erscheint auch eine Ruckrechnung mit „transformierten” BAK-Werten oder die Berucksichtigung von angegebenem Nachtrunk nicht moglich. Insbesondere ist ein strafrechtsrelevanter AAK-Grenzwert auch nicht durch einfache Multiplikation zu errechnen, sondern bedarf einer breiten experimentellen psycho-physiologischen und verkehrsmedizinischen Grundlagenforschung.

Summary Plasminogen activators as inducible extracellular serine proteases are involved in a variety of processes, such as the degradation of brain structures. In regions of brain degradation, an increase in the expression of genes encoding cytokines and proteinases has recently been demonstrated. We tested the hypothesis, whether the plasminogen activator system as well as the Plasminogen activator inhibitors are expressed and possibly involved in a proteolytic cascade that breaks down the extracellular matrix as a result of ischemic or posttraumatic brain destructions. To study this supposition, we investigated immunohistochemically the expression of tPA, uPA and its receptor, the plasminogen activator inhibitors PAI-1 and PAI-2, tetranectin as well as the laminin breakdown as an event of secondary brain injury. Brain tissue from 21 autopsy cases with severe brain injuries, material from 14 ischemic infarcts and 11 controls with acute hypoxia were used. All components of the plasminogen activator system studied were overexpressed immunohistochemically in reactive astrocytes, microglia and endothelial cells around the lesion zone. Tetranectin showed an analogous distribution to the plasminogen activator system. A reduced immunoreactivity of laminin within the identical region of destruction was detected concomitant with laminin remnants in perivascular macrophages, so that a remarkable role of the plasmin cascade in the degradation of extracellular matrix proteins in the brain is taken into consideration.

Dopamine and the dopamine-derived tetrahydroisoquinoline alkaloids salsolinol and norsalsolinol were measured by high-performance liquid chromatography with electrochemical detection in 15 regions of the human brain. The regional distribution of dopamine in 32 brains was similar to previous reports with highest concentrations in the basal ganglia, especially in the striatum, followed by the substantia nigra and the hypothalamus. Significant amounts of salsolinol and norsalsolinol were only found in these dopamine-rich areas, whereas in the other regions no alkaloids were detected. These findings suggest that the concentration of the substrate dopamine may determine the alkaloid level during in vivo formation.

The aim of this study was the determination of D-loop heteroplasmy in astrocytic brain tumors. DNA fragments corresponding to the hypervariable region 2 of the mitochondrial displacement loop (D-loop) from 12 astrocytic tumors and 2 corresponding brain samples were cloned into a plasmid vector. Heteroduplex analysis revealed high sequence variability in the brain samples and a subfraction of grade 2 and grade 3 tumors. Furthermore, the results were suggestive of a very low degree of heteroplasmy in all glioblastomas. This was confirmed by direct sequencing of 223 cloned DNA samples from nine individuals. Heteroplasmy was caused in most cases by a well-known length polymorphism of a homopolymeric c-tract. Heteroplasmy of the two reference brain samples was lost in the corresponding tumors. Genes Chromosomes Cancer 26:80-83, 1999.

A universal property of spiking neurons is refractoriness, a transient decrease in discharge probability immediately following an action potential (spike). The refractory period lasts only one to a few milliseconds, but has the potential to affect temporal coding of acoustic stimuli by auditory neurons, which are capable of submillisecond spike-time precision. Here this possibility was investigated systematically by recording spike times from chicken auditory nerve fibersin vivowhile stimulating with repeated pure tones at characteristic frequency. Refractory periods were tightly distributed, with a mean of 1.58 ms. A statistical model was developed to recapitulate each fiber's responses and then used to predict the effect of removing the refractory period on a cell-by-cell basis for two largely independent facets of temporal coding: faithful entrainment of interspike intervals to the stimulus frequency and precise synchronization of spike times to the stimulus phase. The ratio of the refractory period to the stimulus period predicted the impact of refractoriness on entrainment and synchronization. For ratios less than ∼0.9, refractoriness enhanced entrainment and this enhancement was often accompanied by an increase in spike-time precision. At higher ratios, little or no change in entrainment or synchronization was observed. Given the tight distribution of refractory periods, the ability of refractoriness to improve temporal coding is restricted to neurons responding to low-frequency stimuli. Enhanced encoding of low frequencies likely affects sound localization and pitch perception in the auditory system, as well as perception in nonauditory sensory modalities, because all spiking neurons exhibit refractoriness.

A fundamental question in neuroscience is how neurons perform precise operations despite inherent variability. This question also applies to neuromorphic engineering, where low-power microchips emulate the brain using large populations of diverse silicon neurons. Biological neurons in the auditory pathway display precise spike timing, critical for sound localization and interpretation of complex waveforms such as speech, even though they are a heterogeneous population. Silicon neurons are also heterogeneous, due to a key design constraint in neuromorphic engineering: smaller transistors offer lower power consumption and more neurons per unit area of silicon, but also more variability between transistors and thus between silicon neurons. Utilizing this variability in a neuromorphic model of the auditory brain stem with 1,080 silicon neurons, we found that a low-voltage-activated potassium conductance ( gKL) enables precise spike timing via two mechanisms: statically reducing the resting membrane time constant and dynamically suppressing late synaptic inputs. The relative contribution of these two mechanisms is unknown because blocking gKL in vitro eliminates dynamic adaptation but also lengthens the membrane time constant. We replaced gKL with a static leak in silico to recover the short membrane time constant and found that silicon neurons could mimic the spike-time precision of their biological counterparts, but only over a narrow range of stimulus intensities and biophysical parameters. The dynamics of gKL were required for precise spike timing robust to stimulus variation across a heterogeneous population of silicon neurons, thus explaining how neural and neuromorphic systems may perform precise operations despite inherent variability.

The ability to obtain accurate histories for a comparative study of compulsive overeating and alcoholism was severely compromised by the high degree of denial, shame and self-blame present in these two overlapping disease entities. Areas of overlap included similar progression of the disease, familial tendencies, and the presence of protein enzymatic markers for alcoholism within the bariatric population. Since both shame-based diseases tend to run in the same families, four techniques were developed to reduce the amount of shame that obese patients experienced when talking about family histories and their own compulsive, obsessive disease as it progresses through five identifiable stages. These techniques include: the use of specific non-shaming words and gestures; normalization of patients' history and experiences; education about similar biological, genetic, progressive, stress-related diseases to solidify the disease concept of obesity; and a loosely structured interview format which proceeds from the general to the specific and the past to the present, in an orderly, non-shaming fashion.

We investigate two-point correlation functions of left-handed currents computed in quenched lattice QCD with the Neuberger-Dirac operator. We consider two lattice spacings a ~ 0.09, 0.12 fm and two different lattice extents L ~ 1.5, 2.0 fm; quark masses span both the p- and the epsilon-regimes. We compare the results with the predictions of quenched chiral perturbation theory, with the purpose of testing to what extent the effective theory reproduces quenched QCD at low energy. In the p-regime we test volume and quark mass dependence of the pseudoscalar decay constant and mass; in the epsilon-regime, we investigate volume and topology dependence of the correlators. While the leading order behaviour predicted by the effective theory is very well reproduced by the lattice data in the range of parameters that we explored, our numerical data are not precise enough to test next-to-leading order effects., S. N. is supported by Marie Curie Fellowship MEIF-CT-2006-025673. S. N. and P. H. aknowledge partial support by Spanish Ministry for Education and Science under grant FPA2004- 00996 and Generalitat Valenciana under grant GVACOMP2007-156. C. P. acknowledges support from the Ramón y Cajal Programme, as well as by the research grant FPA2006-05807 and the Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042) of the Spanish Ministry for Education and Science. L. G., P. H., S. N. and H. W. are partially supported by EC Sixth Framework Program under the contract MRTN-CT-2006-035482 (FLAVIAnet).

38 pages, 9 figures.-- Published in: JHEP05(2008)043, available at: http://dx.doi.org/10.1088/1126-6708/2008/05/043 (open-acess)., A new method to determine the low-energy couplings of the ΔS=1 weak Hamiltonian is presented. It relies on a matching of the topological poles in 1/m2 of three-point correlators of two pseudoscalar densities and a four-fermion operator, measured in lattice QCD, to the same observables computed in the ε-regime of chiral perturbation theory. We test this method in a theory with a light charm quark, i.e. with an SU(4) flavour symmetry. Quenched numerical measurements are performed in a 2 fm box, and chiral perturbation theory predictions are worked out up to next-to-leading order. The matching of the two sides allows to determine the weak low-energy couplings in the SU(4) limit. We compare the results with a previous determination, based on three-point correlators containing two left-handed currents, and discuss the merits and drawbacks of the two procedures., We acknowledge the computer resources provided by IBM MareNostrum at the BSC, the IBM Regatta at FZ Jülich and the PC-clusters at University of Valencia. P.H. and E.T. acknowledge partial financial support from the research grants FPA-2004-00996, FPA-2007-01678, FLAVIAnet and HA2005-0120. C.P. acknowledges financial support from the Ramón y Cajal programme, as well as the research grant FPA2006-05807. C.P. and P. H. acknowledge support from the Consolider-Ingenio 2010 Programme CPAN (CSD2007-00042).

We present a silicon neuron with a dynamic, active leak that enables precise spike-timing with respect to a time-varying input signal. Our neuron models the mammalian bushy cell, which enhances the phase-locking of its acoustically driven inputs. Our model enhances phase-locking by up to 38% (quantified by vector strength) across a 60 dB range of acoustic intensities, and up to 22% over a passive leak. Its conductance-based log-domain design yields a compact and efficient circuit, fabricated in 0.25 /spl mu/m CMOS, that is an ideal timing-enhancing component for neuromorphic speech recognition systems.

At the forensic autopsy of a sexual murder victim, some trace hairs, possibly belonging to the perpetrator, were saved. Initially, the analysis of a pubic hair shaft only revealed the presence of the mitochondrial (mt) DNA haplotype profile consisting of the (CA)(6) allele and the complete hypervariable region 1 (HV1) and 2 (HV2) sequence. Later, typing of some further telogene trace hairs, which had been stored for several years, yielded a nuclear short tandem repeat (STR) profile. We used both the mtDNA haplotype and the STR profile to start a DNA mass screening project involving 2,335 male citizens of the relevant communities. MtDNA screening was carried out by using the CA repeat amplification in combination with an SNP typing procedure based on the restriction site analysis of amplified d-loop sequences. The aim of our paper is to put mass screening with mtDNA up for discussion.

Sequence analysis of the human mitochondrial genome (mtDNA) has proven to be a valuable tool in forensic identity testing and the analysis of crime scene stains. In contrast to the very expensive sequencing technique, typing of different length variants can greatly facilitate screening of a large number of traces for their relevance during casework. Within the mitochondrial control region, a dinucleotide (CA) n repeat locus is present. To assess the discrimination power of this marker, we have determined (CA) n allele distribution and the frequency of heteroplasmy in a population sample of 2,458 Germans. The inclination to develop heteroplasmic mixtures (CA) n /(CA) n−1 was positively correlated with the number of CA repeats in the mtDNA. In addition, we have studied the inheritance patterns of (CA) n repeat sequence heteroplasmy in two pedigrees. In one pedigree, we also found a length heteroplasmy in the homopolymeric C-tract (nt 303–309). Our data show stable inheritance of heteroplasmy within the homopolymeric C-stretch, but rather unstable inheritance regarding the (CA) n repeat locus.

Background The nematode Caenorhabditis elegans is widely used for the genetic analysis of neuronal cell biology, development, and behavior. Because traditional methods for evaluating behavioral phenotypes are qualitative and imprecise, there is a need for tools that allow quantitation and standardization of C. elegans behavioral assays. Results Here we describe a tracking and imaging system for the automated analysis of C. elegans morphology and behavior. Using this system, it is possible to record the behavior of individual nematodes over long time periods and quantify 144 specific phenotypic parameters. Conclusions These tools for phenotypic analysis will provide reliable, comprehensive scoring of a wide range of behavioral abnormalities, and will make it possible to standardize assays such that behavioral data from different labs can readily be compared. In addition, this system will facilitate high-throughput collection of phenotypic data that can ultimately be used to generate a comprehensive database of C. elegans phenotypic information. Availability The hardware configuration and software for the system are available from wschafer@ucsd.edu.

We present a strategy designed to separate several possible origins of the well-known enhancement of the Delta{I}=1/2 amplitude in non-leptonic kaon decays. In particular, we seek to disentangle the contribution of physics at the typical QCD scale (soft-gluon exchange) from the effects at the scale of the charm quark mass. This is achieved by considering QCD with an unphysically light charm quark, so that the theory possesses an approximate SU(4)_L x SU(4)_R chiral symmetry. By computing the relevant operator matrix elements and monitoring their values as the charm quark mass departs from the SU(4)-symmetric situation, the role of the charm quark can be assessed. We study the influence of the charm quark mass in Chiral Perturbation Theory. First results from lattice simulations in the SU(4)-symmetric limit are also discussed., Latex, 41 pages, 5 figures

Mitochondrial DNA sequences of the hypervariable regions HV I and HV II were analyzed in 300 unrelated individuals born and living in the northeast corner of Germany (Western Pomerania) to generate a database for forensic identification purposes in this region. Sequence polymorphism were detected using PCR and direct sequencing analysis. A total of 242 different haplotypes were found as determined by 147 variable positions. The most frequent haplotype (263G, 315.1C) was found in 10 individuals and is also the most common sequence in Europe. Three other haplotypes were shared by 5 individuals, 2 sequences by 4, 8 haplotypes by 3, 15 sequences by 2 persons, and 213 sequences were unique. The genetic diversity was estimated to be 0.99 and the probability of two random individuals showing identical mitochondrial DNA (mtDNA) haplotypes is 0.6%. A comparison with other studies from Germany showed only little differences in the distribution of haplogroups. Nevertheless, one frequent haplotype in northeast Germany (five unrelated individuals) could only rarely be found in other German and European regions. Our results may indicate that despite a high admixture proportion in the German population some regions could demonstrate certain characteristic features.

Identification in forensic casework by mtDNA sequencing is predominantly done by sequencing the non-coding control region (HVI and HVII). In an attempt to further increase the discriminatory power of mtDNA analysis, we sequenced a coding region between nt8306 and nt9021 to identify additional polymorphisms in a group of 61 unrelated German individuals who had mtDNA profiles that occurred more than two times each, as well as a control group of 119 unrelated Germans whose profiles occurred one or two times each. Within these 180 individuals, 38 different polymorphisms in this region were observed; 64.4% of these individuals displayed the Cambridge reference sequence profile plus A8860G. For 28 individuals with the two most common profiles, A263G-315.1insC (N=18) and A263G-309.1insC-315.1insC (N=10), additional polymorphisms in this coding region permitted further discrimination of 56 and 40% of the individuals, respectively.

Objective Post-mortem CT-angiography is a valuable addition to post mortem diagnostics due to its ability to reliably discover discrete vascular pathologies. While different approaches are being pursued across the world, the need for validation and standardization of the method increases in order to facilitate its transition into daily routine. With this aim, an international working group has been performing a prospective multicenter study to validate the technique, define its indications and evaluate its advantages and limitations, especially compared to conventional autopsy. Methods and materials We report the results of the first 200 of 500 planned cases. All cases received previously published Multi Phase Post Mortem Angiography (MPMCTA) followed by conventional autopsy. All findings were recorded for each method and categorized by anatomical structure (bone, parenchyma, soft tissue, vascular) and importance for the forensic case (essential, useful, not important). Results Most findings were visualized with both techniques. MPMCTA was superior to autopsy at identifying skeletal and vascular lesions, where it detected a number of significant lesions not seen at autopsy. On the other hand, conventional autopsy provided better information about parenchyma lesions and was more accurate at distinguishing post-mortem and intra-vital vascular occlusions. Best results were obtained when combining both techniques. Conclusion MPMCTA can reveal important findings, not visible at conventional autopsy. Still, some diagnoses remain autopsy-diagnoses. Optimal results are obtained by combining both techniques. When finished, the ongoing study will provide researchers and practitioners with a solid data base and help promote the transition of MPMCTA into daily routine.

We report a case in which STR typing failed to identify the minor component of a mixed saliva stain, but a mitochondrial restriction analysis succeeded in discriminating between the two components. To identify the nt16093 and nt16265 transitions, the template was amplified with the mismatch primers L16092-mm16085 and H16266-mm16269. In the presence of the transitions the mismatch primers created a BsaB I and a Cac8 I restriction site, respectively. Subsequently, aliquots were restricted separately using the enzymes Cac8 I and BsaB I which clearly identified the minor stain component.

Sequencing of mtDNA is an advanced method for the individualisation of traces. Disadvantages of this method are expensive and time-consuming analysis and evaluation procedures as well as the necessary stock of population-genetic data which is still insufficient. Central European institutes of forensic medicine from Germany, Austria, and Switzerland have been working together since the beginning of 1998 to establish a mtDNA database. The aim is to build up a large stock of forensically established data and provide population-genetic data for frequency investigations, which will serve as a basis for expert opinions and scientific research. Good data quality is ensured by using original sequences only. Ring tests, which have been conducted to enhance analytical reliability, revealed a high correspondence rate of the analytical results obtained by the individual member institutes. Today 1410 sequences are available for comparison, of which 1285 sequences in the HV1 and HV2 regions cover the full ranges from 16051 to 16365 and from 73 to 340 (according to Anderson). The major part is formed by Central European sequences comprising 1256 data sets from Germany, Austria, and Switzerland. Today the database contains sequences from a total of 12 European, six African and three Asian countries including 100 sequences from Japan. This paper is aimed at discussing the individualisation potentials of mtDNA as well as the possibilities and limits of ethnic differentiation by means of pairwise sequence differences on the basis of the data stock available.

We propose a general method to obtain accurate estimates for some of the "low-energy constants" in the one-loop effective chiral Lagrangian by means of simulating lattice QCD. In particular, the method is sensitive to those constants whose values are required to test the hypothesis of a massless up-quark. Initial tests performed in the quenched approximation confirm that good statistical precision can be achieved. As a byproduct we obtain an accurate estimate for the ratio of pseudoscalar decay constants, F_K/F_pi, in the quenched approximation, which lies 10% below the experimental result. The quantities that serve to extract the low-energy constants also allow a test of the scaling behaviour of different discretizations of QCD and a search for the effects of dynamical quarks., 27 pages, 9 postscript files, LaTeX; Corrections in Appendix A and Table 1; numerical results and conclusions unchanged; version to be published in Nucl. Phys. B

Similarities between alcoholism and morphinism concerning the development of an addiction and symptoms of withdrawal led to the hypothesis that opiate-active compounds might be formed endogenously during the establishment of alcohol addiction (Huber and Melzig, 1992). This theory was supported by the proof of in vivo formation of various alkaloids in the human body. One hypothesis invoked the ethanol metabolite acetaldehyde as a critical intermediate in the biosynthesis of opiate-active compounds. Acetaldehyde can condense directly with catecholamines in tissues to form substituted 6,7-dihydroxy-l,2,3,4-tetrahydroisoquinolines, the most discussed compound being salsolinol (SAL). SAL might be formed in vivo by a non-enzymatic ring cyclization of dopamine (DA) with the ethanol oxidation product acetaldehyde to yield the racemic mixture of both, the (R)- and (S)-enantiomer. Another pathway is the condensation of dopamine with pyruvic acid, followed by enzymatic decarboxylation and reduction.

The static potential in the 3d SU(2) Higgs model is computed by a variational calculation employing Wilson loops and two-meson operators. String breaking is demonstrated numerically, the breaking scale is determined and the results are compared with a quenched calculation., LATTICE98(higgs), 3 pages Latex, 3 figs. Presented at the International Symposium on Lattice Field Theory, 13.7.-18.7.1998, Boulder, Colorado

Im Rahmen des Verbund-Forschungsprojekts ARGUS werden unter anderem Untersuchungen zur Sicherheit der Werkstuckspannung bei der Hochgeschwindigkeitsbearbeitung durchgefuhrt. Im vorliegenden Beitrag wird uber neue Ergebnisse berichtet, die aus FEM-Untersuchungen zu Fragen der Spannsicherheit beim Hochgeschwindigkeitsdrehen stammen. In Erweiterung vorangegangener Modellierungen und Simulationen wurden hier die Vorspannung zwischen Spannmittel und Werkstuck, Spanungskrafte und Unwuchten mit einbezogen. Auch die Probleme der Modellbildung wurden vermehrt beachtet.

I report on cost estimates and algorithmic performance in simulations using 2 flavours of non-perturbatively O(a) improved Wilson quarks together with the Wilson plaquette action., Comment: Contribution to Lattice2001 (panel discussion), 2 pages, 2 figures

The hemodynamic effect of myocardial revascularization with saphenous vein grafts (mean 3.3 per patient) was analyzed I year after operation in 111 patients. Operations were performed using one continuous period of aortic cross-clamping with hyperkalemic cardioplegia for distal anastomoses in 84% of patients; 16% had arrest with topical and systemic hypothermia for myocardial protection. Group I (N = 18) had normal ventricles (ejection fraction [EF] ≥ 50%; left ventricular end-diastolic pressure [LVEDP] ≤ 12 torr); Group II (N = 64) had ischemic ventricles (EF ≥ 50%, LVEDP > 13 torr); and Group III (N = 30) had abnormal ventricles (EF 13 torr). Hemodynamic measurements were obtained before and 1 year after operation. Fifteen of 18 patients (83%) in Group I did not show significant hemodynamic changes, but in three EF decreased by ≥ 10% and LVEDP increased by ≥ 10% over preoperative levels. In Group II, EF was unchanged or slightly better in 89% (57/64) and worse in seven patients. Improvement in cardiac index (p 35% to

In 3 patients with ischemic coronary disease or primary myocardiopathy who were unresponsive to conventional and experimental antiarrhythmia therapy, surgical treatment of intractable ventricular tachycardia was performed using epicardial, transmural, and endocardial mapping techniques. An experimental canine model of acute and chronic myocardial ischemia with recurrent ventricular tachycardia was developed to refine the mapping technique for clinical use. In patients and animals alike, atrial overdrive pause pacing, premature ventricular pacing, or both were used to bring out a repeatable pattern of tachycardia. Mapping techniques distinguished the irritable focus so that surgical excision of the site of earliest activation could be performed. In addition, the mapping techniques were used in the validation following excision. The limitations of epicardial mapping alone in locating all areas of premature focus are discussed, and the need for mapping in ventricular aneurysm is demonstrated.

L9146 was synthesised in the hope of eliminating the unwanted side-effects of amiodarone which has been shown to be effective in the control of atrial fibrillation, flutter, and in pre-excitation syndromes such as Wolff-Parkinson-White syndrome. L9146 has pharmacological and electrophysiological effects similar to those of amiodarone. It is an antagonist of both alpha and beta adrenoceptor-mediated cardiovascular effects of a noncompetitive type. It lowers vascular resistance briefly, and causes a longer lasting bradycardia. It moderately reduces the maximum rate of depolarisation (MRD), conduction velocity, and totally suppresses ventricular pacemakers activated by high doses of isoprenaline. In addition, L9146 greatly prolongs action potential duration (APD) in atrial and ventricular muscle. In normal ventricular conducting tissue the action potential duration (APD) is shorter in the bundle of His than in the false tendons, and shorter still in the ventricular muscle. L9146 lengthened APD throughout, but particularly in the proximal portion, and even more in the muscle, so that APD became uniform. The decrement of conduction of premature action potentials was increased to the point at which slowly conducting premature AP's were eliminated altogether.

Jaundice is rarely encountered in polycystic disease of the liver. In the present case, pressure from tense cysts at the hilus of the liver caused a marked narrowing of the common hepatic duct and slowing of bile flow with the formation of stasis stones. Decompression of the cysts and removal of debris in the intrahepatic ducts resulted in a rapid decrease of the serum bilirubin level.

Es werden verschiedene Aufschlusverfahren zur Bestimmung des anorganisch gebundenen Quecksilbers und des Gesamtquecksilbers in Futtermitteln ohne vorherige Anreicherung dargestellt. Der angewandte Salpetersaure-Permanganat-Kaltaufschlus erfast ca. 80% des gesamten Quecksilbergehaltes, wahrend mit dem reinen Salpetersaureaufschlus der groste Teil des anorganischen Quecksilbers, aber nur ca. 20% des organischen Quecksilbers aufgefunden werden. Aus der Differenz der ermittelten Hg-Gehalte in beiden Aufschlussen wird der Gehalt an organisch gebundenem Hg berechnet. Weiterhin werden die Bestimmungsapparatur und die Mesmethode auf der Grundlage der flammenlosen AAS vorgestellt. Die optimalen Bestimmungsparameter werden uberpruft. Die Nachweisgrenze der Methode liegt bei 10 ng. Die Ergebnisse zeigen, das ca. 63 % des Gesamtquecksilbergehaltes als organisch gebundenes Quecksilber in den Futtermitteln vorlagen.

We apply the operator-“blocking” algorithm to the SU(2) Higgs model. This algorithm, which was developed to yield a higher signal for correlations in glueball calculations leads to a better projection property of lattice operators for the Higgs- and the W-boson. Furthermore, blocked operators give bigger hysteresis signals, and the jump in the gauge-fixed link at the phase transition increases with higher blocking level. Thus, the method may have some impact on future studies of possible changes in the order of the phase transition.