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Texturally complex monazite grains contained in two granulite-facies pelitic migmatites from southern Baffin Island, Arctic Canada, were mapped by laser ablation-inductively coupled plasma-mass spectrometry (using spot sizes < 5 µm) to quantitatively determine the spatial variation in trace element chemistry (with up to 1883 analyses per grain). The maps highlight the chemical complexity of monazite grains that have experienced multiple episodes of growth, resorption and chemical modification by dissolution-precipitation during high-grade metamorphism. Following detailed chemical characterisation of monazite compositional zones, a related U-Pb dataset is re-interpreted, allowing petrologically-significant ages to be extracted from a continuum of concordant data. Synthesis of these data with pseudosection modelling of prograde and peak conditions allows for the temporal evolution of monazite trace element chemistry to be placed in the context of the evolving P-T conditions and major phase assemblage. This approach enables a critical evaluation of three commonly used petrochronological indicators: linking Y to garnet abundance, the Eu anomaly to feldspar content, and Th/U to anatectic processes. Europium anomalies and Th/U behave in a relatively systematic fashion, suggesting that they are reliable petrochronological witnesses. However, Y systematics are variable, both within domains interpreted to have grown in a single event, between grains interpreted to be part of the same age population, and between samples that experienced similar metamorphic conditions and mineral assemblages. These observations caution against generalised petrological interpretations on the basis of Y content, as it suggests Y concentrations in monazite are controlled by domainal equilibria. The results reveal a ~45 Myr interval between prograde metamorphism and retrograde melt crystallisation in the study area, emphasising the long-lived nature of heat flow in high-grade metamorphic terranes. Such long timescales of metamorphism would be assisted by the growth, retention and dominance of high-Th suprasolidus monazite, as observed in this study, contributing to the radiogenic heating budget of mid- to lower-crustal environments. Careful characterisation of monazite grains suggests that continuum-style U-Pb datasets can be decoded to provide insights into the duration of metamorphic processes.

Phenazine-1-carboxylic acid (PCA) is produced by rhizobacteria in dryland but not in irrigated wheat fields of the Pacific Northwest, USA. PCA promotes biofilm development in bacterial cultures and bacterial colonization of wheat rhizospheres. However, its impact upon biofilm development has not been demonstrated in the rhizosphere, where biofilms influence terrestrial carbon and nitrogen cycles with ramifications for crop and soil health. Furthermore, the relationships between soil moisture and the rates of PCA biosynthesis and degradation have not been established. In this study, expression of PCA biosynthesis genes was upregulated relative to background transcription, and persistence of PCA was slightly decreased in dryland relative to irrigated wheat rhizospheres. Biofilms in dryland rhizospheres inoculated with the PCA-producing (PCA+ ) strain Pseudomonas synxantha 2-79RN10 were more robust than those in rhizospheres inoculated with an isogenic PCA-deficient (PCA- ) mutant strain. This trend was reversed in irrigated rhizospheres. In dryland PCA+ rhizospheres, the turnover of 15 N-labelled rhizobacterial biomass was slower than in the PCA- and irrigated PCA+ treatments, and incorporation of bacterial 15 N into root cell walls was observed in multiple treatments. These results indicate that PCA promotes biofilm development in dryland rhizospheres, and likely influences crop nutrition and soil health in dryland wheat fields.

An integrated field, petrological and geochronological study of the Basong Tso region of south-eastern Tibet has constrained the timing and P–T conditions of north–south Lhasa terrane accretion and provides new insight into the tectonothermal evolution of the Tibetan plateau. Two distinct high-grade metamorphic belts are recognized in the region: a southern belt (the Basong Tso complex) that consists of sheared schist and orthogneiss; and a northern belt (the Zhala complex) that comprises paragneiss and granite. Combined pseudosection modelling and U–Pb geochronology of monazite and zircon indicates that the Basong Tso complex records peak metamorphic conditions of 9 ± 0.5 kbar and 690 ± 25 °C at c. 204–201 Ma, whereas the Zhala complex experienced peak metamorphic conditions of 5.0 ± 1.0 kbar and 740 ± 40 °C at c. 198–192 Ma. Microstructural analysis suggests that the two belts share a common early prograde history, after which the Basong Tso complex attained peak conditions following rapid burial, and the Zhala complex approached peak conditions along an isobaric path. Overall it is inferred that the Basong Tso and Zhala complexes represent the lower and upper structural levels of an evolving orogen that underwent Barrovian-type metamorphism following collision (M1), followed by Buchan-style overprinting at higher structural levels due to heat advection by syn-tectonic granites (M2). Mylonitization (sensu lato) of the Basong Tso complex and juxtaposition of the two units occurred after attainment of peak conditions. The dominance of Mesozoic regional metamorphism across most of the Tibetan plateau indicates that Cenozoic crustal thickening processes, where present, are only manifested at depth.

The aim of this study was to inventory the types of plant growth-promoting rhizobacteria (PGPR) present in the rhizosphere of plants grown in soils contaminated with heavy metals, recalcitrant organics, petroleum sewage or salinity in China. We screened 1223 isolates for antifungal activity and about 24% inhibited Rhizoctonia solani or Sclerotinia sclerotiorum. Twenty-four strains inhibitory to R. solani, Gaeumannomyces graminis var. tritici and/or S. sclerotiorum and representing the dominant morphotypes were assayed for PGPR activity. Seven strains contained phlD, prnD, pltC or phzF genes and produced the antibiotics 2,4-diacetylphloroglucinol, pyrrolnitrin, pyoluteorin and phenazines respectively. Six strains contained acdS, which encodes 1-aminocyclopropane-1-carboxylic acid deaminase. Phylogenetic analysis of 16S rDNA and phlD, phzF and acdS genes demonstrated that some strains identified as Pseudomonas were similar to model PGPR strains Pseudomonas protegens Pf-5, Pseudomonas chlororaphis subsp. aureofaciens 30–84 and P. brassicacearum Q8r1-96. Pseudomonas protegens- and P. chlororaphis-like strains had the greatest biocontrol activity against Rhizoctonia root rot and take-all of wheat. Pseudomonas protegens and P. brassicacearum-like strains showed the greatest promotion of canola growth. Our results indicate that strains from contaminated soils are similar to well-described PGPR found in agricultural soils worldwide. Growth-promoting rhizobacteria in polluted soils

Objective To determine the prevalence and nature of trigeminal neuralgia in a large group of cluster headache patients. Background Cluster-tic syndrome is a rare headache syndrome in which trigeminal neuralgia and cluster headache co-occur. The existence of cluster-tic syndrome as a separate entity is questioned, and figures on prevalence of simultaneous existence of cluster headache and trigeminal neuralgia are not available. Methods As part of a nationwide study on headache mechanisms in cluster headache (Leiden University Medical Centre Cluster headache Neuro Analysis programme), we collected clinical data of 244 cluster headache patients using a semistructured telephone interview in a cross-sectional design. Results In 11 (4.5%) cluster headache patients, attacks fulfilling International Headache Society criteria for trigeminal neuralgia were also present. In all cases, trigeminal neuralgia occurred ipsilateral to cluster headache and in the majority (82%) in the ophthalmic branch. In 8 of these 11 patients (73%), the frequency and time pattern of trigeminal neuralgia seemed to parallel cluster headache and was likely a part of the cluster headache spectrum. In the 3 remaining patients, cluster headache and trigeminal neuralgia were unrelated in time and appeared to occur independently. Conclusion Trigeminal neuralgia co-occurred in 11/244 (4.5%) of cluster headache patients. In only 3 (1.2%) patients, trigeminal neuralgia seemed to occur independently from cluster headache episodes. Trigeminal neuralgia (-like) attacks in cluster headache patients are most of the time part of the cluster headache spectrum and should then probably not be treated separately. A shared underlying pathophysiological mechanism of cluster headache and trigeminal neuralgia is not supported by this study.

In situ measurements of nonlinear waveforms produced by a PIN diode under large-signal excitation have been performed using ultrafast electro-optic (EO) sampling.The waveforms were sampled using an EO probe positioned immediately after the diode. These data validate a nonlinear model and improve representation of the waveform across the circuit. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2653–2656, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27119

Phenazine compounds represent a large class of bacterial metabolites that are produced by some fluorescent Pseudomonas spp. and a few other bacterial genera. Phenazines were first noted in the scientific literature over 100 years ago, but for a long time were considered to be pigments of uncertain function. Following evidence that phenazines act as virulence factors in the opportunistic human and animal pathogen Pseudomonas aeruginosa and are actively involved in the suppression of plant pathogens, interest in these compounds has broadened to include investigations of their genetics, biosynthesis, activity as electron shuttles, and contribution to the ecology and physiology of the cells that produce them. This minireview highlights some recent and exciting insights into the diversity, frequency and ecological roles of phenazines produced by fluorescent Pseudomonas spp.

Hermaphroditism has evolved several times independently in nematodes. The model organism Caenorhabditis elegans and Pristionchus pacificus are self-fertile hermaphrodites with rare facultative males. Both species are members of different families: C. elegans belongs to the Rhabditidae and P. pacificus to the Diplogastridae. Also, both species differ in their ecology: C. elegans is a soil-dwelling nematode that is often found in compost heaps. In contrast, field studies in Europe and North America indicate that Pristionchus nematodes are closely associated with scarab beetles. In C. elegans, several recent studies have found low genetic diversity and rare out-crossing events. Little is known about diversity levels and population structure in free-living hermaphroditic nematodes outside the genus Caenorhabditis . Taking a comparative approach, we analyse patterns of molecular diversity and linkage disequilibrium in 18 strains of P. pacificus from eight countries and four continents. Mitochondrial sequence data of P. pacificus isolates reveal a substantially higher genetic diversity on a global scale when compared to C. elegans . A mitochondrialderived hermaphrodite phylogeny shows little geographic structuring, indicating several worldwide dispersal events. Amplified fragment length polymorphism and single strand conformation polymorphism analyses demonstrate a high degree of genome-wide linkage disequilibrium, which also extends to the mitochondrial genome. Together, these findings indicate distinct patterns of genetic variation of the two species. The low level of genetic diversity observed in C. elegans might reflect a recent human-associated dispersal, whereas the P. pacificus diversity might reflect a long-lasting and ongoing insect association. Thus, despite similar lifestyle characteristics in the laboratory, the reproductive mode of hermaphroditism with rare facultative males can result in distinct genetic variability patterns in different ecological settings.

The purpose of this study was to assess the frequency and content of alcoholic beverage advertisements and sales promotions in magazines popular with adolescents and young people in Australia, and assess the extent to which the ads complied with Australia's self-regulatory Alcoholic Beverages Advertising Code (ABAC). Alcohol advertisements and promotions were identified in a sample of 93 magazines popular with young people. The identified items were coded against 28 measures constructed to assess the content of the items against the five sections of the ABAC. Two thirds of the magazines contained at least one alcohol advertisement or promotion with a total of 142 unique items identified: 80 were brand advertisements and 62 were other types of promotional items (i.e. sales promotions, event sponsorships, cross promotions with other marketers and advertorials). It was found that 52% of items appeared to contravene at least one section of the ABAC. The two major apparent breaches related to section B--the items having a strong appeal to adolescents (34%) and to section C--promoting positive social, sexual and psychological expectancies of consumption (28%). It was also found that promotional items appeared to breach the ABAC as often as did advertisements. It is concluded that the self-regulating system appears not to be working for the alcoholic beverages industry in Australia and that increased government surveillance and regulation should be considered, giving particular emphasis to the inclusion of promotional items other than brand advertising.

Skulls of odontocetes (toothed whales, including dolphins and porpoises) are typified by directional asymmetry, particularly in elements associated with the airway. Generally, it is assumed this asymmetry is related to biosonar production. However, skull asymmetry may actually be a by-product of selection pressure for an asymmetrically positioned larynx. The odontocete larynx traverses the pharynx and is held permanently in place by a ring of muscle. This allows prey swallowing while remaining underwater without risking water entering the lungs and causing injury or death. However, protrusion of the larynx through the pharynx causes a restriction around which prey must pass to reach the stomach. The larynx and associated hyoid apparatus has, therefore, been shifted to the left to provide a larger right piriform sinus (lateral pharyngeal food channel) for swallowing larger prey items. This asymmetry is reflected in the skull, particularly the dorsal openings of the nares. It is hypothesized that there is a relationship between prey size and skull asymmetry. This relationship was examined in 13 species of odontocete cetaceans from the northeast Atlantic, including four narrow-gaped genera (Mesoplodon, Ziphius, Hyperoodon, and Kogia) and eight wide-gaped genera (Phocoena, Delphinus, Stenella, Lagenorhynchus, Tursiops, Grampus, Globicephala, and Orcinus). Skulls were examined from 183 specimens to assess asymmetry of the anterior choanae. Stomach contents were examined from 294 specimens to assess prey size. Results show there is a significant positive relationship between maximum relative prey size consumed and average asymmetry relative to skull size in odontocete species (wide-gape species: R2 = 0.642, P = 0.006; narrow-gape species: R2 = 0.909, P = 0.031). This finding provides support for the hypothesis that the directional asymmetry found in odontocete skulls is related to an aquatic adaptation enabling swallowing large, whole prey while maintaining respiratory tract protection.

The field of juvenile justice has made great strides in developing a research base of effective practices and principles, including an understanding of risk factors and needs that contribute to juvenile offending. However, the research base and practice of systematic assessment has not yet fully incorporated youth, family, and community strengths. To address this need, three juvenile justice agencies in the northwestern United States participated in a pilot study to develop and implement an assessment tool (the Youth Competency Assessment) and process that would identify and utilize strengths to help balance the risk and needs focus of their assessment and case planning practices., This article provides descriptions and implementation strategies of the three pilot sites. The article concludes with recommended system changes and policy interventions to support ongoing utilization of this kind of strength-based tool in juvenile justice settings, and a clear set of recommendations for other communities wishing to implement strength-based assessment in their own agencies. Language: en

Juvenile justice lacks an agreed-upon assessment tool blending strength-based approaches with rehabilitative and punitive measures. The recently-piloted Youth Competency Assessment (YCA) is presented as one way to offer a strength-based tool compatible with traditional risk- and problem-based approaches. YCA's development and piloting processes are described, and the theoretical underpinnings supporting its three domains are summarized and analyzed.

This paper describes optimal coplanar waveguide (CPW) 2nd harmonic notch filters that utilize metal-insulator-metal (MIM) capacitors at each discontinuity, eliminating the need for conventional air-bridges and significantly reducing the filter footprint. The circuits were fabricated on a high resistivity, 400 μm-thick silicon substrate. Theoretical and experimental data for 42 GHz notch filters employing straight and bent shunt stubs are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 292–295, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10745

Investigation of the short-term (90-day) stability of the Adjustment Scales for Children and Adolescents is reported for 124 randomly selected children in grades ranging from kindergarten to grade 12. Significant test-retest stability coefficients were obtained and mean differences across the retest interval did not exceed .8 raw score points. The Solitary Aggressive-Impulsive, Diffident, and Lethargic/Hypoactive syndromes and the global Underactivity scale showed significant raw score and T score changes across the retest interval, but the effect strengths were small. Syndromic Profile Classifications and Discriminant Classifications were also significantly consistent across the retest interval. Results were similar to those obtained in other stability studies of teacher report behavior rating scales. © 2001 John Wiley & Sons, Inc.

BACKGROUND This retrospective single-center study assesses the feasibility, therapeutic outcome, and late side effects of combined modality therapy with intravenous methotrexate, whole brain radiotherapy (WBRT), and intravenous cytarabine in patients with primary central nervous system lymphoma (PCNSL). METHODS All 28 consecutive patients diagnosed with PCNSL between 1991 and 1997 were scheduled to receive combined modality therapy. Seven of 28 patients did not receive combined modality treatment: 6 patients had WBRT alone because of poor physical condition, and 1 patient died before receiving treatment. Of the remaining 21 patients, 5 received the complete regimen, and 16 received a modified regimen with reduced dose intensity. RESULTS Fourteen of 21 patients (67%) treated with combined modality therapy had a complete response; 1 had a partial response. Median survival was 11 months in all 28 patients, 23 months in all patients with combined modality treatment, and 41 months in patients receiving the complete regimen. Of 15 examinable patients with a follow-up of 8 months or more, 10 developed severely symptomatic and 5 mildly symptomatic or asymptomatic diffuse white matter changes. CONCLUSION Only a small subgroup of all patients with PCNSL appears to be eligible for receiving all parts of the combined modality regimen. Treatment in these patients leads to a marked prolongation of survival. The risk of late side effects is high even with modified, dose intensity–reduced versions of combined modality treatment. Cancer 2001;91:130–5. © 2001 American Cancer Society.

Air-core inductors are large-body, low-loss components that find frequent use in circuits such as RF power amplifier matching networks. The physical attributes of the inductors make loss characterization using standard commercial instruments (e.g., impedance analyzers or resonant coaxial lines) problematic. In this paper, a resistance and quality factor extraction technique based on low-impedance microstrip test fixtures is demonstrated at frequencies near 800 MHz. It is shown that an inductor resistance on the order of 0.1–1 Ω can be accurately determined. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 29: 89–93, 2001.

This article introduces a 20-μm tall, 75-μm wide rectangular polyimide core micro coaxial transmission line that can be realized using a simplified fabrication procedure. Measurements of a 4-bend, meandered micro coaxial line demonstrate an 8% increase in the insertion loss and a 2% variation in the phase compared with a straight line of equivalent length. Cross-coupling below 30 dB up to 65 GHz has been measured between two micro coaxial lines separated by 175 μm. These properties make the structures as useful building blocks for highly miniaturized and integrated microwave circuitry. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1291–1293, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25212

BACKGROUND Altered expression of Bcl-2 family proteins has been associated with tumorigenesis and tumor progression as well as resistance to radiotherapy and chemotherapy. In the current study, Bcl-2 family protein expression was examined in oligodendrogliomas and anaplastic oligodendrogliomas, and an attempt was made to determine whether these proteins accumulate during disease progression and to search for protein expression patterns predictive of time to progression and overall survival. METHODS A total of 42 oligodendroglioma tissue samples, 26 de novo World Health Organization (WHO) Grade 2 oligodendrogliomas, and 16 de novo WHO Grade 3 anaplastic oligodendrogliomas were studied. Nineteen Grade 2 tumors progressed: 10 again were Grade 2 oligodendrogliomas and 8 had progressed to higher grade lesions. Eight anaplastic oligodendrogliomas progressed: five again were WHO Grade 3 tumors and three were glioblastoma multiforme. Expression of Bcl-2, Bax, Bcl-X, and Mcl-1 proteins and of the proliferation marker Ki-67 was evaluated by immunohistochemistry. Apoptotic cells were quantified by in situ nick translation (ISNT). RESULTS De novo WHO Grade 2 oligodendrogliomas had higher Bcl-2 scores (P = 0.037), lower MIB-1 scores (P = 0.0012), and lower ISNT scores (P = 0.049) compared with de novo WHO Grade 3 anaplastic oligodendrogliomas. In de novo oligodendrogliomas, low numbers of Bax positive cells were associated with a short time to disease progression (P = 0.043). In de novo anaplastic oligodendrogliomas, low numbers of Bcl-2 positive cells correlated with short survival (P = 0.029). In tumors that had progressed from WHO Grade 3 anaplastic oligodendrogliomas, the authors found significantly more Bcl-X positive (P = 0.005), Mcl-1 positive (P = 0.002), and Bax positive (P = 0.03) cells. CONCLUSIONS The results of the current study show that progression of oligodendrogliomas and anaplastic oligodendrogliomas is associated with an enhanced expression of antiapoptotic Bcl-2 family proteins. Cancer 1999;86:1832–9. © 1999 American Cancer Society.

In cubic Y 2 O 3 (10-25 mol%) or CaO (14 and 17 mol%) stabilized ZrO 2 , oxygen vacancies are created as charge-compensating defects. Mechanical loss (internal friction) measurements are performed on single crystals of cubic zirconia with various orientation at frequencies of f 1 Hz and 1 kHz, to study the local crystallographic structure of the defects. The mechanical spectra show a composite loss maximum at 400-600 K consisting of two overlapping submaxima: I and I A in ZrO 2 -Y 2 O 3 ; I' and I' A in ZrO 2 -CaO. Submaxima I (I') are assigned to defect pairs of oxygen vacancies and impurity atoms forming elastic (and electric) dipoles. These are oriented parallel to , with the vacancy on nearest neighbour sites (trigonal symmetry). Submaxima I A (I' A ) are attributed to relaxation of vacancies within Y- (or Ca-) clusters with various sizes and configurations corresponding to lower defect symmetry. The electrical conductivity (4 probe d.c. technique) decreases for concentrations ≥ 10 mol% Y 2 O 3 , whereas the activation enthalpy increases with Y 2 O 3 content. A high temperature peak C in ZrO 2 -CaO around 1400 K (0.1 Hz) is probably due to local atomic jumps of cations.

Recent developments in micromachining techniques at the University of Michigan have resulted in novel high-performance low-loss filters for microwave and millimeter-wave applications. The idea is based on suspending the filters on thin dielectric membranes to eliminate dielectric loss and dispersion problems, resulting in a pure TEM mode of propagation and conductor-loss-limited performance. The dielectric membrane and the surrounding cavities are built using chemical etching in Silicon and GaAs wafers. The filters are therefore compatible with low-cost IC fabrication techniques and can be com- bined with planar diodes and transistors to result in active filter networks. Several state-of-the-art filters have been realized including 15-GHz and 20-GHz bandpass interdigi- tal suspended stripline filters, lowpass and bandpass microshield filters at 30 GHz and 90 GHz, microstrip 94-GHz bandpass filters, and a 250-GHz bandpass filter with 1.0-1.5-dB insertion loss. This article reviews the associated fabrication techniques, the different types of transmission lines achieved using this technology, and the measured performance from 15 to 350 GHz. The study concludes with a detailed description of the future work in this area. Q 1997 John Wiley & Sons, Inc. Int J Microwa'e Millimeter-Wa'e CAE 7: 149-166, 1997.

Hypovirulent Gaeumannomyces graminis var. tritici strain L108hv, five strains of Pseudomonas spp., and a mixture of four of these bacterial strains were used individually and in combination for the suppression of take-all of wheat. In the growth chamber, L108hv and all five individual bacterial strains provided a significant reduction in take-all severity compared with an untreated control. Combination of Ll08hv and the bacteria did not significantly enhance the suppressiveness of either agent. In the field at Pullman, WA, 108hv significantly reduced crown root infection of winter wheat but not seminal root infection, while the reverse was true for a mixture of bacterial strains suggesting these agents may be more effective at different stages in disease development. In a second field trial at Pullman, yield of spring wheat was increased by 20.8%. In contrasts in two field trials at Mt. Vernon, WA, L108hv had no effect on take-all of spring wheat. We conclude that specific biocontrol agents may be better suited for certain environments and that biocontrol treatments should be customized for the target site.

The high sensitivity of the magnetic after-effect (MAE) and internal friction (IF) on the presence of interstitially dissolved carbon (C) and nitrogen (N) in α-iron (Fe) is utilized for the quantitative analysis of corresponding impurity concentrations. The calibration of respective relaxation strengths is achieved, following precise chemical analyses of identically C- and N-doped Fe samples, under consideration of method-specific influences such as, i.e., texture of polycrystalline Fe samples (IF), geometry- and frequency-dependent demagnetizing factors and skin-effect (MAE). In agreement with theoretical calculations, the following strength parameters for IF and MAE of C and N, respectively, are determined: Q/cC ≃ Q/cN = 1.8 × 10−5 at ppm−1, and (Δr∞/r0)C/cC = 1.3 × 10−2 at ppm−1, (Δr∞/r0)N/cN = 0.65 × 10−2 at ppm−1, yielding detection limits, in the case of the MAE, of

The power dissipation characteristics of CPW-to-slotline transitions are discussed. The resonant stub chosen to terminate one CPW slot in these transitions has a significant effect on the transition loss. Series-stub designs are shown to reduce energy loss by 2.5–3 times on a low-dielectric-constant substrate, as compared to the more common radial-stub design. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 91–93, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20057

This paper describes coplanar waveguide (CPW) quadrature couplers that utilize metal–insulator–metal (MIM) capacitors at each corner, eliminating the need for air bridges and significantly reducing the coupler footprint. A 20 GHz coupler on high-resistivity silicon with branch lengths of 40° (660 μm) is presented—the area is 80% smaller than a conventional design. A measured insertion loss of ∼4.5±0.5 dB was achieved at 20 GHz. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 3–5, 2001.

Summary A course of lectures, given by William Herapath in Bristol in 1836, during which nitrous oxide was administered on six occasions, is described.

Rates of depletion and half-lives of linoleic acid from epididymal, subcutaneous and retroperitoneal fat pads and the residual body were compared among 5 genetically diverse strains of mice: M16, a polygenic obese line developed by selection for high postweaning gain; ICR, a control line from which M16 was derived; H6, a nonobese strain selected for large 6-week body weight; L6, selected for small 6-week body weight; and C2 a control line from which H6 and L6 were initiated. Rates of depletion and half-lives of linoleic acid were obtained on a fat-free diet following an enrichment period of feeding a diet high in linoleic acid. The M16 mice have an increased capability of synthesizing fat from carbohydrates as shown by a continued increase in fat depot weights when fed the fat-free diet. The 4 other lines showed no subsequent increase in fat depot weights on the fat-free diet. Rates of depletion of linoleic acid were significantly different among lines in each of the 4 depots. Ranking of lines for depletion rates was similar among the 3 discrete depots, but a more rapid rate of depletion was observed in subcutaneous and retroperitoneal fat depots than in the epididymal fat depot. Rates of depletion in line M16 were slower than in the ICR control line. Line H6 had a slower rate of depletion than line L6. Line L6 deviated more from the C2 control than did line H6, indicating an asymmetric correlated selection response. The decreased depletion rate of linoleic acid in fat tissue of M16 and H6 mice suggests the possibility that the turnover rates of fatty acids have been reduced in these lines as a result of a reduction in lipolytic activity. The increased depletion rate of linoleic acid in L6 mice suggests that selection for small body size has substantially increased the rate of fat turnover. The experiment demonstrates that genetic differences among lines in fat turnover have accurued as corelated responses to selection for growth rate.

The defect structure in 3 mol% Y-TZP was studied by correlated internal friction, dielectric loss, and ionic conductivity experiments. A prominent mechanical and dielectric loss peak occurs in the temperature range between 380 and 550 K that depends on the frequency of measurement. The relaxation parameters were determined as Hm= 90 ± 3 kJ·mol−1, τ∞= (1.0+1.5−0.6) × 10−14 s for the mechanical relaxation and Hd= 84 ± 3 kJ·mol−1, τ∞= (1.6+1.7−0.9) × 10–13 s for the dielectric relaxation. The ionic conductivity below 790 K is controlled by an activation enthalpy of Hσ= 89 ± 3 kJ·mol−1; at higher temperatures Hσ= 60 ± 3 kJ·mol–1. An atomistic model is presented which assumes that oxygen vacancies are trapped by yttrium ions forming anisotropic complexes which—by reorientation—cause anelastic and dielectric relaxation. At higher temperatures (>790 K) these complexes are dissociated, which leads to the reduced activation enthalpy for ionic conductivity.

— Two procedures are described for preparing from ox brain grey matter a subcellular fraction enriched in neuronal membranes. In the first, an angle rotor was used to fractionate the crude mitochondrial and nuclear fraction and yielded 1·3–1·4 g of membrane protein from 200 g of tissue. The second procedure employed essentially the same principle except that a zonal rotor was used to fractionate in the final stage. The two methods gave comparable results for yields of protein, Na-K-Mg AT Pase and succinate dehydrogenase.