bluuebunny/crossref_metadata_2025 huggingface dataset:
Write-erase and read paper memory transistor
Authors: Martins Rodrigo , Barquinha Pedro , Pereira Luís , Correia Nuno , Gonçalves Gonçalo , Ferreira Isabel , Fortunato Elvira
Published: November 2008

We report the architecture and the performances of a memory based on a single field-effect transistor built on paper able to write-erase and read. The device is composed of natural multilayer cellulose fibers that simultaneously act as structural support and gate dielectric; active and passive multicomponent amorphous oxides that work as the channel and gate electrode layers, respectively, complemented by the use of patterned metal layers as source/drain electrodes. The devices exhibit a large counterclockwise hysteresis associated with the memory effect, with a turn-on voltage shift between 1 and −14.5V, on/off ratio and saturation mobilities of about 104 and 40cm2V−1s−1, respectively, and estimated charge retention times above 14000h.
Compensation of thermal refraction effect in high-Q toroidal microresonator by polydimethylsiloxane coating
Authors: He L. , Xiao Y.-F. , Dong C. , Zhu J. , Gaddam V. , Yang L.
Published: November 2008

We experimentally and theoretically characterize the thermal refraction effect in a silica microtoroid and demonstrate that such effect can be reduced or even eliminated by applying a thin layer of polydimethylsiloxane (PDMS) to the surface of the silica resonator. By increasing the coating thickness, the whispering gallery modes (WGMs) experience a transition from redshift to blueshift induced by thermal absorption. Experiment results demonstrate that at the thickness of 0.52 μm, the fundamental WGM with observed Q factor of 1.5×106 shows no shift with the input optical power since the thermal refraction of the silica for this mode is compensated completely by the PDMS layer, which has an opposite thermal refraction effect. This work shows that the PDMS layer could be used to reduce thermal noise in high-Q silica microcavities for applications in sensing, lasing, and nonlinear optics.
The future biological control of pest populations of European rabbits, Oryctolagus cuniculus
Authors: Henzell Robert P. , Cooke Brian D. , Mutze Gregory J.
Published: November 2008

European rabbits are exotic pests in Australia, New Zealand, parts of South America and Europe, and on many islands. Their abundance, and the damage they cause, might be reduced by the release of naturally occurring or genetically modified organisms (GMOs) that act as biological control agents (BCAs). Some promising pathogens and parasites of European rabbits and other lagomorphs are discussed, with special reference to those absent from Australia as an example of the range of necessary considerations in any given case. The possibility of introducing these already-known BCAs into areas where rabbits are pests warrants further investigation. The most cost-effective method for finding potentially useful but as-yet undiscovered BCAs would be to maintain a global watch on new diseases and pathologies in domestic rabbits. The absence of wild European rabbits from climatically suitable parts of North and South America and southern Africa may indicate the presence there of useful BCAs, although other explanations for their absence are possible. Until the non-target risks of deploying disseminating GMOs to control rabbits have been satisfactorily minimised, efforts to introduce BCAs into exotic rabbit populations should focus on naturally occurring organisms. The development of safe disseminating GMOs remains an important long-term goal, with the possible use of homing endonuclease genes warranting further investigation.
A robust baseline for bottlenose dolphin abundance in coastal Moreton Bay: a large carnivore living in a region of escalating anthropogenic impacts
Authors: Lukoschek Vimoksalehi , Chilvers B. Louise
Published: November 2008

Marine megafauna populations in coastal waters are increasingly threatened by anthropogenic impacts. Moreton Bay, a large embayment in south-east Queensland, lies adjacent to one of the fastest growing regions in Australia and has a resident population of bottlenose dolphins, Tursiops aduncus. Evaluation of the effectiveness of any proposed management strategy requires robust population abundance estimates. We estimated abundances of bottlenose dolphins in central eastern Moreton Bay (350 km2) using two commonly used abundance estimation methods for cetaceans: photo-identification mark–recapture and line-transect surveys. Mark–recapture data were analysed in CAPTURE using a model that allowed capture probabilities to vary between sampling events and between individuals. Based on an estimated 76% of the population identifiable photographically, total abundance estimates were 673 ± 130 s.e. (1997) and 818 ± 152 s.e. (1998). Line-transect data, analysed using DISTANCE, gave an abundance estimate of 407 ± 113.5 s.e. (2000). These abundance estimates are large compared with many other coastal bottlenose dolphin populations. The line-transect surveys comprised a pilot study, and the lower line-transect abundance estimate is probably best attributable to methodological issues. In particular, smaller mean group size was estimated for the line-transects surveys (2.85 ± 0.29 s.e.) than the mark–recapture surveys (4.87 ± 0.39 s.e., 1997; 5.78 ± 0.73 s.e., 1998), and line-transect group sizes were probably underestimated. In addition, the line-transect detection probability (g(o)) was assumed to be one but was almost certainly less than one. However, the possibility of an actual decline in population size cannot be ruled out. Coefficients of variation (CV) were lower for mark–recapture than for line-transect surveys, however, CVs of line-transect estimates could be lowered through improved survey design. We evaluated the power of these surveys to detect trends in potential population declines for bottlenose dolphins in Moreton Bay and make recommendations for ongoing monitoring strategies.
Freshwater turtles of the Kikori Drainage, Papua New Guinea, with special reference to the pig-nosed turtle, Carettochelys insculpta
Authors: Georges Arthur , Alacs Erika , Pauza Matthew , Kinginapi Felix , Ona Amos , Eisemberg Carla
Published: November 2008

A survey of the Kikori River drainage of the Gulf Province of Papua New Guinea identified four species of freshwater turtle. The pig-nosed turtle Carettochelys insculpta and the southern New Guinea soft-shelled turtle Pelochelys bibroni are riverine species. The New Guinea spotted turtle Elseya novaeguineae lives primarily in the tidal freshwater creeks and streams, flooded sinkholes and swamps of the lowland rainforest. The New Guinea painted turtle Emydura subglobosa resides almost exclusively in forest sinkholes and swamps. Pelochelys bibroni was the least-common species, and is probably locally endangered. Greatest turtle diversity occurred in the Karst Plains of the Kikori sub-basin, where there is a greater diversity of habitat available to turtles. Lowest diversity occurred in the highlands, where turtles were present in very low density as introduced populations, brought in from the Kikori lowlands, Mount Bosavi and the Western Province by visiting relatives. Linguistic diversity concurred with turtle diversity of the regions in which the languages were spoken. C. insculpta nests both on riverine sand beaches and on coastal beaches, sand spits and isolated sand bars where the Kikori River discharges into the Gulf of Papua. Adult females and eggs of C. insculpta are harvested heavily by local people for local consumption.
Differences in foraging behaviour of sympatric coots with different conservation status
Authors: Varo Nico , Amat Juan A.
Published: November 2008

Red-knobbed coot, Fulica cristata, was formerly distributed across several countries in the south-west Palaearctic. Remnant populations are now located in Morocco and Spain. In the latter, the red-knobbed coot is considered critically endangered, and its decline is attributed to changes in agricultural practices in the basins of wetlands, which have affected the quality and quantity of food. However, red-knobbed coot is currently more abundant in Morocco. Foraging behaviour reveals information about an animal’s perception of the place that it currently occupies. Thus, we hypothesised that if habitat quality is lower in Spain than in Morocco, this should be expressed in the foraging activity of coots, which should be greater in Spain to compensate for the lower food availability. Our results supported this prediction: red-knobbed coots spent more time foraging in Spain than in Morocco. Furthermore, we compared the foraging behaviour of red-knobbed and common coots, Fulica atra, in southern Spain, where common coot does not face conservation problems, and found that red-knobbed coots spent more time foraging than common coots to meet daily energetic needs. Overall, our results suggested that constraints of food quality and quantity on habitat use were more severe for red-knobbed coots than for common coots, and that this may be a key factor for the conservation of red-knobbed coot in Spain. Managers should try to facilitate longer hydroperiods in wetlands, which would ensure higher quality food during longer periods for coots.
Can CORE assessment data identify those clients less likely to benefit from brief counselling in primary care?
Authors: Saxon David , Ivey Catherine , Young Tracey
Published: November 2008

Studies show that counsellors in primary care see many clients with difficulties of a severity similar to those found in secondary care services. Evidence from both RCTs and studies of routinely collected data indicates that many of these ‘clinical’ clients benefit from brief counselling intervention. However, little is known about why some benefit while others fail to do so despite completing their counselling contract. This paper considers client characteristics recorded at assessment and aims, using logistic regression analysis, to identify those characteristics predictive of a poor outcome. Results indicate that a number of characteristics are associated with poor outcome; the most important predictors are economic inactivity and aspects of the patient's condition, particularly continuous/recurrent depression, with some differences between genders. However, the models produced were not acceptable in their predictive power. This may be partly due to data quality issues or important characteristics not being available in the data. The paper concludes that being unemployed or on state benefits may be a proxy measure of severity that has an important impact on outcome for all patients, and particularly for males. Some reasons are suggested and areas of future research are identified.
A five‐year evaluation of the effectiveness of person‐centred counselling in routine clinical practice in primary care
Authors: Gibbard Isabel , Hanley Terry
Published: November 2008

Counselling is the recommended treatment for individuals with mild to moderate mental health problems of recent onset. In this evaluation of a primary care counselling service offering person‐centred counselling, the Core Outcome Measure (CORE‐OM) was administered at referral and at the beginning and end of therapy. A pre‐post therapy effect size for 697 individuals over a 5 year period was 1.2. This compares with a waitlist (between referral and pre therapy) effect size of 0.24 for 382 individuals over a three year period. The results indicate that person‐centred counselling is effective for clients with common mental health problems, such as anxiety and depression. Effectiveness is not limited to individuals with mild to moderate symptoms of recent onset, but extends to people with moderate to severe symptoms of longer duration.
Developing clinical effectiveness in psychotherapy training: Action research
Authors: Van Rijn Biljana , Sills Charlotte , Hunt Jill , Shivanath Suhith , Gildebrand Katarina , Fowlie Heather
Published: November 2008

This study is an evaluation of a new approach to clinical training in Transactional Analysis using the methodology of action research. The evaluation focuses on the second year of training and placement‐based clinical practice at the Metanoia Institute, UK. The design of the training year was research‐based and used the concept of an ‘internship’ year. The design aimed to close the gaps between clinical practice, supervision and formal training; facilitate translation of theory into practice; and integrate findings from the ‘common factors’ research into effectiveness of psychotherapy. Training and supervision methods were linked and focused on emerging issues in clinical practice and the development of students’ capacity for critical reflection and a research attitude to practice. The evaluation was a naturalistic study which used quantitative and qualitative methodology within the action research framework to reflect on the impact of the training on the participants, the organisation and the clinical practice. The quantitative outcomes show that the project developed the effectiveness of students’ clinical practice and reflexivity. Qualitative analysis gives insight into the experiences of the participants and the emotional impact of the research process.
The psychological impact of bereavement on insecurely attached adults in a primary care setting
Authors: McChrystal Jane
Published: November 2008

Aims: this study investigated the psychological effects of bereavement from an attachment perspective within a primary care setting. It hoped to examine associations between bereavement, insecure patterns of attachment and psychological symptoms. Method: bereaved adults (n=36) recruited from 2 general practices participated in the Modified Adult Attachment Interview in order to assess their state of mind with regard to attachment according to a discourse analytic method. Levels of depression and anxiety recorded in participants’ medical records were compared in the year before and after bereavement. The medical records of a group of non‐bereaved adults (n=20) were also compared over 2 years. Results: interview transcripts were assigned to the insecure category and the participant group had significantly higher levels of psychological symptoms after bereavement when compared with the control group. It was not possible to establish a link between insecure attachment and raised levels of psychological symptoms after bereavement due to the absence of securely attached individuals from the research sample. Conclusions: this study supports evidence of the adverse effects of bereavement on mental health. It provides insights into the psychological characteristics and needs of a group of bereaved adults in a primary care setting, which could be used to inform the practice of counsellors and other health care professionals.
Constructive conversations: Revisiting selected developments with clients and counsellors
Authors: Strong Tom , Nielsen Kate
Published: November 2008

Aim: to examine client and counsellor experiences in using and responding to social constructionist (e.g. solution‐focused, narrative and collaborative approaches) questions and other conversational interventions. Method: retrospective comments were elicited from 32 clients and 12 counsellors (trained in social constructionist counselling approaches) in reviewing their videotaped use of (or response to) questions and interventions from the social constructionist approaches in single session lifestyle consultations. These comments were transcribed then analysed using the constant comparison method of grounded theory. Results: five common themes (but with different emphases for clients and counsellors) were identified: exploring and adopting the client's perspective; identifying alternative perspectives; identifying strengths, possibilities, and solutions; developing a shared understanding; struggling to talk in a different way. Conclusions: the findings will be useful to counsellors interested in improving their responsive use of questions and interventions in dialogues with clients.
Re‐establishing contact: A qualitative exploration of how therapists work with alliance ruptures in adolescent psychotherapy
Authors: Binder Per-Einar , Holgersen Helge , Høstmark Nielsen Geir
Published: November 2008

What challenges do therapists face when they experience ruptures in the working alliance in psychotherapy with adolescent clients; and what are their most typical strategies when they try to re‐establish contact? These issues were explored through qualitative interviews with nine psychotherapists from outpatient child and adolescent psychiatric clinics in Bergen, Norway. A descriptive and hermeneutically informed phenomenological approach was used to analyse the interview transcripts. Most therapists/participants described that they would explore the reason for the rupture from the adolescent's point of view, and all participants often understood ruptures in light of the adolescents’ need for autonomy. However, the participants differed strongly in how much they would focus on the relationship per se, on intrapsychic factors, or on the adolescent's life outside therapy. For the therapists who regarded the relationship as something to be explored, client ambivalence to treatment was seen as something that could be confirmed and validated. If not, ambivalence seemed more likely to be handled as a choice situation. Therapists who explored ambivalence also tried to develop ways to talk about fluctuations in the adolescent's motivation and distress, and often interpreted ‘not wanting therapy’ as a way of communicating difficulties with the relationship.
HP1-β is required for development of the cerebral neocortex and neuromuscular junctions
Authors: Aucott Rebecca , Bullwinkel Jörn , Yu Yang , Shi Wei , Billur Mustafa , Brown Jeremy P. , Menzel Ursula , Kioussis Dimitris , Wang Guozheng , Reisert Ingrid , Weimer Jörg , Pandita Raj K. , Sharma Girdhar G. , Pandita Tej K. , Fundele Reinald , Singh Prim B.
Published: November 2008

HP1 proteins are thought to be modulators of chromatin organization in all mammals, yet their exact physiological function remains unknown. In a first attempt to elucidate the function of these proteins in vivo, we disrupted the murine Cbx1 gene, which encodes the HP1-β isotype, and show that the Cbx1−/−-null mutation leads to perinatal lethality. The newborn mice succumbed to acute respiratory failure, whose likely cause is the defective development of neuromuscular junctions within the endplate of the diaphragm. We also observe aberrant cerebral cortex development in Cbx1−/− mutant brains, which have reduced proliferation of neuronal precursors, widespread cell death, and edema. In vitro cultures of neurospheres from Cbx1−/− mutant brains reveal a dramatic genomic instability. Our results demonstrate that HP1 proteins are not functionally redundant and that they are likely to regulate lineage-specific changes in heterochromatin organization.
Fast regulation of AP-1 activity through interaction of lamin A/C, ERK1/2, and c-Fos at the nuclear envelope
Authors: González José María , Navarro-Puche Ana , Casar Berta , Crespo Piero , Andrés Vicente
Published: November 2008

Sequestration of c-Fos at the nuclear envelope (NE) through interaction with A-type lamins suppresses AP-1–dependent transcription. We show here that c-Fos accumulation within the extraction-resistant nuclear fraction (ERNF) and its interaction with lamin A are reduced and enhanced by gain-of and loss-of ERK1/2 activity, respectively. Moreover, hindering ERK1/2-dependent phosphorylation of c-Fos attenuates its release from the ERNF induced by serum and promotes its interaction with lamin A. Accordingly, serum stimulation rapidly releases preexisting c-Fos from the NE via ERK1/2-dependent phosphorylation, leading to a fast activation of AP-1 before de novo c-Fos synthesis. Moreover, lamin A–null cells exhibit increased AP-1 activity and reduced levels of c-Fos phosphorylation. We also find that active ERK1/2 interacts with lamin A and colocalizes with c-Fos and A-type lamins at the NE. Thus, NE-bound ERK1/2 functions as a molecular switch for rapid mitogen-dependent AP-1 activation through phosphorylation-induced release of preexisting c-Fos from its inhibitory interaction with lamin A/C.
Phosphorylation sites in BubR1 that regulate kinetochore attachment, tension, and mitotic exit
Authors: Huang Haomin , Hittle James , Zappacosta Francesca , Annan Roland S. , Hershko Avram , Yen Timothy J.
Published: November 2008

BubR1 kinase is essential for the mitotic checkpoint and also for kinetochores to establish microtubule attachments. In this study, we report that BubR1 is phosphorylated in mitosis on four residues that differ from sites recently reported to be phosphorylated by Plk1 (Elowe, S., S. Hummer, A. Uldschmid, X. Li, and E.A. Nigg. 2007. Genes Dev. 21:2205–2219; Matsumura, S., F. Toyoshima, and E. Nishida. 2007. J. Biol. Chem. 282:15217–15227). S670, the most conserved residue, is phosphorylated at kinetochores at the onset of mitosis and dephosphorylated before anaphase onset. Unlike the Plk1-dependent S676 phosphorylation, S670 phosphorylation is sensitive to microtubule attachments but not to kinetochore tension. Functionally, phosphorylation of S670 is essential for error correction and for kinetochores with end-on attachments to establish tension. Furthermore, in vitro data suggest that the phosphorylation status of BubR1 is important for checkpoint inhibition of the anaphase-promoting complex/cyclosome. Finally, RNA interference experiments show that Mps1 is a major but not the exclusive kinase that specifies BubR1 phosphorylation in vivo. The combined data suggest that BubR1 may be an effector of multiple kinases that are involved in discrete aspects of kinetochore attachments and checkpoint regulation.
Differential roles of ArfGAP1, ArfGAP2, and ArfGAP3 in COPI trafficking
Authors: Weimer Carolin , Beck Rainer , Eckert Priska , Reckmann Ingeborg , Moelleken Jörg , Brügger Britta , Wieland Felix
Published: November 2008

The formation of coat protein complex I (COPI)–coated vesicles is regulated by the small guanosine triphosphatase (GTPase) adenosine diphosphate ribosylation factor 1 (Arf1), which in its GTP-bound form recruits coatomer to the Golgi membrane. Arf GTPase-activating protein (GAP) catalyzed GTP hydrolysis in Arf1 triggers uncoating and is required for uptake of cargo molecules into vesicles. Three mammalian ArfGAPs are involved in COPI vesicle trafficking; however, their individual functions remain obscure. ArfGAP1 binds to membranes depending on their curvature. In this study, we show that ArfGAP2 and ArfGAP3 do not bind directly to membranes but are recruited via interactions with coatomer. In the presence of coatomer, ArfGAP2 and ArfGAP3 activities are comparable with or even higher than ArfGAP1 activity. Although previously speculated, our results now demonstrate a function for coatomer in ArfGAP-catalyzed GTP hydrolysis by Arf1. We suggest that ArfGAP2 and ArfGAP3 are coat protein–dependent ArfGAPs, whereas ArfGAP1 has a more general function.
Golgi coiled-coil proteins contain multiple binding sites for Rab family G proteins
Authors: Sinka Rita , Gillingham Alison K. , Kondylis Vangelis , Munro Sean
Published: November 2008

Vesicles and other carriers destined for the Golgi apparatus must be guided to the correct cisternae. Golgins, long coiled-coil proteins that localize to particular Golgi subdomains via their C termini, are candidate regulators of vesicle sorting. In this study, we report that the GRIP domain golgins, whose C termini bind the Arf-like 1 G protein on the trans-Golgi, can also bind four members of the Rab family of G proteins. The Rab2-, Rab6-, Rab19-, and Rab30-binding sites are within the coiled-coil regions that are not required for Golgi targeting. Binding sites for two of these Rabs are also present on two coiled-coil proteins of the cis-Golgi, the Drosophila melanogaster orthologues of GM130 and GMAP-210. We suggest an integrated model for a tentacular Golgi in which coiled-coil proteins surround the Golgi to capture and retain Rab-containing membranes, excluding other structures such as ribosomes. Binding sites for diverse Rabs could ensure that incoming carriers are captured on first contact and moved to their correct destination within the stack.
Limiting lumens: a new role for Cdc42
Authors: Lechler Terry
Published: November 2008

The formation of a single lumen is a necessary step in the formation of biological tubes. Different tissues have developed diverse ways to form their lumens. In this issue, Jaffe et al. (Jaffe, A.B., N. Kaji, J. Durgan, and A. Hall. 2008. J. Cell Biol. 183:625–633) report the development of an in vitro system for studying lumen formation that is driven by fluid transport, recapitulating intestinal lumen formation. Effective ion and fluid transport requires both cell polarity and proper tissue organization. Surprisingly, polarization of cells in this three-dimensional system does not require Cdc42. Instead, Cdc42 prevents formation of multiple lumens by orienting cell divisions and directing apical membrane biogenesis.
Caspase-8 goes cardiolipin: a new platform to provide mitochondria with microdomains of apoptotic signals?
Authors: Scorrano Luca
Published: November 2008

In certain cell types, apoptosis in response to extracellular stimuli like Fas depends on a mitochondrial amplificatory loop: the apical caspase-8 cleaves and activates the BH3-only member of the Bcl-2 family BID. In turn, BID induces the release of cytochrome c from mitochondria to the cytoplasm, where it is required to fully activate effector caspases. In this issue of The Journal of Cell Biology, Gonzalvez et al. (see p. 681) show that when caspase-8 activation and production of functional BID is required, it is performed on mitochondrial platforms provided by the mitochondrion-specific lipid cardiolipin. Cardiolipin anchors caspase-8 at contact sites between inner and outer mitochondrial membranes, facilitating its self activation. These findings suggests that like other second messengers such as Ca2+ and cAMP, production of apoptotic messengers can be compartmentalized in close proximity to their intracellular target.
A false sense of security
Authors: Rossner Mike
Published: November 2008

Some journals are using ineffective software to screen images for manipulation. In doing so, they are creating a false sense of security in the research community about the integrity of the image data they publish.
Electromigration Reliability With Respect to Cu Weight Contents of Sn–Ag–Cu Flip-Chip Solder Joints Under Comparatively Low Current Stressing
Authors: Lai Yi-Shao , Chiu Ying-Ta
Published: November 2008

This work presents electromigration reliability and patterns of Sn–3Ag–0.5Cu and Sn–3Ag–1.5Cu∕Sn–3Ag–0.5Cu composite flip-chip solder joints with Ti∕Ni(V)∕Cu under bump metallurgy (UBM), bonded on Au∕Ni∕Cu substrate pads. The solder joints were subjected to an average current density of 5kA∕cm2 under an ambient temperature of 150°C. Under the situation when electron charges flow from the UBM toward the substrate, Sn diffuses from the Cu–Ni–Sn intermetallic compound developed around the UBM toward the UBM and eventually causes the Ni(V) layer to deform. Electromigration reliability of Sn–3Ag–1.5Cu∕Sn–3Ag–0.5Cu composite flip-chip solder joints was found to be better than that of Sn–3Ag–0.5Cu solder joints. According to the morphological observations on cross-sectioned solder joints, a failure mechanism is proposed as follows. Since the deformation of the Ni(V) layer as a result of Sn diffusion toward the UBM is considered as the dominant failure, a greater Cu weight content in the solder joints would trap more Sn in the Sn–Cu interfacial reaction and would therefore retard the diffusion of Sn toward the UBM and hence enhance the electromigration reliability.
Optimization of Pool Boiling Heat Sinks Including the Effects of Confinement in the Interfin Spaces
Authors: Geisler Karl J. L. , Bar-Cohen Avram
Published: November 2008

A finite element analysis approach is developed and used to efficiently evaluate and optimize the boiling performance of longitudinal rectangular plate fin heat sinks, including the explicit dependence of fin spacing on boiling heat transfer coefficients and on the critical heat flux (CHF). Polished silicon heat sinks are shown to dissipate at nearly five times the CHF limit of the unfinned base area and outperform comparable aluminum heat sinks by a factor of 2. For optimum heat sink geometries, over the parameter ranges explored, the fin thickness is found to be approximately equal to the fin spacing, and the relationship between the optimum thickness and spacing is demonstrated to be relatively insensitive to the fin thermal conductivity. Results suggest that even greater performance enhancements may be gained with appropriately-selected advanced materials.
Flip-Chip Interconnect for Coplanar Strip Lines
Authors: Song Young K. , Lee Chin C.
Published: November 2008

A flip-chip interconnect configuration with coplanar strip (CPS) lines on printed circuit boards (PCBs) is reported for millimeter-wave applications. For CPS lines, the signal and ground electrodes both lie on the top surface of a chip or substrate. The flip-chip configuration was designed and implemented using a test chip on a dielectric board. Geometrical parameter analysis was carried out using full-wave simulation and equivalent circuit model for wideband performance. The chip was connected to the board using solder bumps. For a typical flip-chip assembly, the measured insertion loss is less than 3dB for frequencies of up to 35GHz and the return loss is higher than 15dB for frequencies of up to 29GHz using CPS flip-chip configuration.
Direct Silver to Copper Bonding Process
Authors: Wang Pin J. , Kim Jong S. , Lee Chin C.
Published: November 2008

A novel process of bonding silver (Ag) foils to copper (Cu) substrates has been developed. This direct bonding method does not use any intermediate layer in between. An important application of this process is electronic packaging where semiconductor device chips are bonded to Cu substrates or Cu electrodes fabricated on substrates. Cu is chosen as the major material for substrates and electrodes due to its high electrical and thermal conductivities, high strength, adequate rigidity, easiness in forging and machining, and low cost. On the other hand, Cu has a large mismatch in the coefficient of thermal expansion with most semiconductors, particularly with silicon. This makes it very difficult to bond large device chips to Cu substrates with a metallic joint. We thus design the Ag-cladded Cu structure to overcome this difficulty. Ag is quite soft and ductile. It can function as a strain buffer between the semiconductor chip and the Cu substrate. Ag also has superior physical properties. It has the highest electrical and thermal conductivities among all metals. In the beginning, we used an electroplating process to produce Ag-cladded Cu substrates. However, it is time consuming and costly to electroplate thick Ag layers. To obtain thick Ag layers (more than 200μm), this new laminating process is developed. The Ag foil is laminated to the Cu substrate directly with a static load of 1000psi at 250°C in a 50mtorr vacuum to suppress oxidation. No bonding medium is used. Scanning electron microscopy images on cross sections of bonded samples exhibit a perfect Ag–Cu bond.
Comparative Studies on Solder Joint Reliability of Plastic and Ceramic Ball Grid Array Packages of the Same Form Factor Under Power and Accelerated Thermal Cycling
Authors: Park S. B. , Joshi Rahul , Ahmed Izhar , Chung Soonwan
Published: November 2008

Experimental and numerical techniques are employed to assess the thermomechanical behavior of ceramic and organic flip chip packages under power cycling (PC) and accelerated thermal cycling (ATC). In PC, nonuniform temperature distribution and different coefficients of thermal expansion of each component make the package deform differently compared to the case of ATC. Traditionally, reliability assessment is conducted by ATC because ATC is believed to have a more severe thermal loading condition compared to PC, which is similar to the actual field condition. In this work, the comparative study of PC and ATC was conducted for the reliability of board level interconnects. The comparison was made using both ceramic and organic flip chip ball grid array packages. Moiré interferometry was adopted for the experimental stress analysis. In PC simulation, computational fluid dynamics analysis and finite element analysis are performed. The assembly deformations in numerical simulation are compared with those obtained by Moiré images. It is confirmed that for a certain organic package PC can be a more severe condition that causes solder interconnects to fail earlier than in ATC while the ceramic package fails earlier in ATC always.
Steady-State Behavior of a Three-Dimensional Pool-Boiling System
Authors: Speetjens Michel
Published: November 2008

Pool-boiling serves as the physical model problem for electronics cooling by means of phase-change heat-transfer. The key for optimal and reliable cooling capacity is better understanding of the conditions that determine the critical heat-flux (CHF). Exceeding CHF results in the transition from efficient nucleate-boiling to inefficient film-boiling. This transition is intimately related to the formation and stability of multiple (steady) states on the fluid-heater interface. To this end, the steady-state behavior of a three-dimensional pool-boiling system has been studied in terms of a representative mathematical model problem. This model problem involves only the temperature field within the heater and models the heat exchange with the boiling medium via a nonlinear boundary condition imposed on the fluid-heater interface. The steady-state behavior is investigated via a bifurcation analysis with a continuation algorithm based on the treatment of the model with the method of separation of variables and a Fourier-collocation method. This revealed that steady-state solutions with homogeneous interface temperatures may undergo bifurcations that result in multiple solutions with essentially heterogeneous interface temperatures. These heterogeneous states phenomenologically correspond with vapor patches (“dry spots”) on the interface that characterize transition conditions. The findings on the model problem are consistent with laboratory experiments.
Managing Thermal Emergencies in Disk-Based Storage Systems
Authors: Kim Youngjae , Choi Jeonghwan , Gurumurthi Sudhanva , Sivasubramaniam Anand
Published: November 2008

Thermal-aware design of disk-drives is important because high temperatures can cause reliability problems. Dynamic thermal management (DTM) techniques have been proposed to operate the disk at the average case temperature, rather than at the worst case by modulating the activities to avoid thermal emergencies caused by unexpected events, such as fan-breaks, increased inlet air temperature, etc. A delay-based approach to adjust the disk seek activities is one such DTM solution for disk-drives. Even if such a DTM approach could overcome thermal emergencies without stopping disk activity, it suffers from long delays when servicing the requests. In this paper, we investigate the possibility of using a multispeed disk-drive (called dynamic rotations per minute (DRPM)), which dynamically modulates the rotational speed of the platter for implementing the DTM technique. Using a detailed performance and thermal simulator of a storage system, we evaluate two possible DTM policies—time-based and watermark-based—with a DRPM disk-drive and observe that dynamic RPM modulation is effective in avoiding thermal emergencies. However, we find that the time taken to transition between different rotational speeds of the disk is critical for the effectiveness of this DTM technique.
Theoretical Modeling and Prediction of Delamination in Flip Chip Assemblies With Nanofilled No-Flow Underfill Materials
Authors: Mahalingam Saketh , Prabhakumar Ananth , Tonapi Sandeep , Sitaraman Suresh K.
Published: November 2008

The occurrence of passivation-underfill interfacial delamination is detrimental to the reliability of the flip chip assembly as it can result in the premature cracking of the solder bumps. In this paper, the propagation of delamination in a nanofilled no-flow underfill material from the chip passivation in flip chip assemblies has been assessed under accelerated thermal shock testing. A theoretical model of the flip chip assembly has been developed, and the delamination occurring at the silicon nitride (SiN)–underfill interface has been studied under monotonic as well as thermomechanical fatigue loading. Using empirical models for delamination propagation, the growth of delamination under monotonic as well as thermomechanical fatigue loading in a flip chip assembly has been predicted. These predictions agree well with the thermal shock cycling experimental data. The agreement between the theoretical predictions and experimental data suggests that the models and the methodology developed in this work can be used to design flip chip assemblies with nanofillled no-flow underfill materials against interfacial delamination.
Chronic and recurrent meningitis
Authors: Ginsberg L , Kidd D
Published: November 2008

Chronic meningitis is defined as the persistence of clinical symptoms and signs of meningitis, with or without abnormal cerebrospinal fluid, for more than four weeks. In as many as one third of cases, no cause is found. In the remainder, infective, neoplastic and so-called aseptic disorders may be identified. Important infective causes include partially treated bacterial (pyogenic), tuberculous, syphilitic, Lyme and fungal meningitis. Sarcoidosis, Behçet’s disease, vasculitis and drugs are major non-infective, non-malignant causes. The definitive diagnosis of the cause of chronic meningitis may be made only after extensive investigation. This review describes the clinical features and causes of chronic and recurrent meningitis, and provides an algorithm for investigation and treatment.
Goya’s deafness
Authors: Smith P E M , Chitty C N , Williams G , Stephens D
Published: November 2008

Francisco Goya (1746–1828), a major Spanish artist, became profoundly deaf aged 46 years, following an acute illness. Despite this, his success continued and he eventually died aged 82 years. His illness is sketchily documented in letters written during his convalescence, describing headache, deafness, tinnitus, unsteadiness and visual disturbance with recovery (apart from deafness) over three months. There was a milder similar illness two years before, suggesting a relapsing condition. Vogt–Koyanagi–Harada syndrome, although previously accepted as Goya’s diagnosis, is not supported by the limited evidence. Susac’s syndrome or Cogan’s syndrome, although both rare, are more likely explanations.
Test for LRRK2 mutations in patients with Parkinson’s disease
Authors: Healy D G , Wood N W , Schapira A H V
Published: November 2008

LRRK2-associated Parkinson’s disease is common enough to raise clinical questions such as which patients should be tested and what advice should be given. We discuss practical issues in the light of our experiences with real life Parkinson’s disease patients. Neurologists should consider testing LRRK2 in Parkinson’s disease patients with affected first degree relatives where the onset is over the age of 40 years. A common G2019S mutation makes genetic testing straightforward and cost-effective. Age-related or reduced genetic penetrance means that LRRK2 mutations are also found in sporadic Parkinson’s disease patients; however, at present, there is little to support the widespread testing of these patients except in high-risk ethnic groups such as North African Arabs and Ashkenazi Jews. Incomplete penetrance also complicates presymptomatic testing, which is best undertaken in the context of appropriate genetic counselling.
Estimation of Whole Pond Respiration Rate
Authors: Madenjian Charles P. , Rogers Gary L. , Fast Arlo W.
Published: November 2008

A regression application of the whole pond respiration–diffusion (WPRD) model to overnight observations of dissolved oxygen concentration (DO) was introduced as a new method to estimate whole pond respiration rate. A new modification of the Welch procedure was also presented. These two techniques were compared with the tangent method for whole pond respiration rate estimation. The tangent method required fitting a quadratic curve to observed DO; and then calculating the slope of the tangent line to the curve at the time the curve reached 100% saturation of DO. When the quadratic was fitted to DO observed during both day and light, the tangent method often yielded inaccurate estimates of whole pond respiration rate. Estimates by the tangent method were sensitive to the time at which 100% saturation of DO occurred. The WPRD model regression and the modified Welch procedure were recommended to estimate whole pond respiration rate.
Serial Passage of Larval Pseudoterranova decipiens (Nematoda:Ascaridoidea) in Fish
Authors: Burt M. D. B. , Campbell J. D. , Likely C. G. , Smith J. W.
Published: November 2008

In one experiment, 24 brook trout (Salvelinus fontinalis) in fresh water at 11 ± 1 °C were each orally infected by intubation with two third-stage larvae of "sealworm" (Pseudoterranova decipiens) harvested from the flesh of sea raven (Hemitripterus americanus) and small Atlantic cod (Gadus morhua). In a second experiment, 27 cod in sea water at 0 °C were each force fed, under anaesthesia, four P. decipiens larvae held in a capelin "purse"; these larvae were harvested from large, commercial size cod. Sequential reinvasion by the same P. decipiens larvae was achieved in both of the serial passage experiments. In brook trout, larvae sequentially reinvaded a maximum of two fish, with larvae of cod origin being the more successful at first passage (62.5%) than those of sea raven origin (31.3 and 37.5%). In cod, larvae also achieved sequential reinvasion of a maximum of two fish; the relatively lower success rates of 22.2% (first passage) and 9.1% (second passage) probably reflect the low temperature (0 °C) at which the experiment was conducted.
Size Selection of Snappers (Lutjanidae) by Hook and Line Gear
Authors: Ralston Stephen
Published: November 2008

The most commonly used theoretical models of gear selection have been the logistic and normal curves. These are usually applied to trawls and gillnets, respectively. In contrast, little critical work has been completed concerning the selective properties of fish hooks, although both types of selectivity curves have arbitrarily been applied to hook catch data in the literature. No study has clearly demonstrated the actual form of a selection curve for hooks. To determine which type of curve (logistic or normal) best describes the selective sampling characteristics of fish hooks, an experiment was conducted in the Marianas Islands during 1982–84. During all fishing operations two different sizes (#20 and #28) of circle fish hooks were fished simultaneously and in equal number. Under these conditions, the length specific ratios of snapper (Lutjanidae) catches taken by the two hook sizes provided a basis for distinguishing which model was most appropriate. Results showed that neither model in its simplest form depicted hook selectivity well. While small hooks caught substantially more small fish, large hooks were somewhat more effective in capturing the larger size classes.
Reconditioning and Reproductive Responses of Atlantic Salmon Kelts (Salmo salar) to Photoperiod and Temperature Manipulation
Authors: Johnston C. E. , Farmer S. R. , Gray R. W. , Hambrook M.
Published: November 2008

The reproductive cycle of reconditioned Atlantic salmon can be manipulated with light and temperature. Wild Atlantic salmon (Salmo salar) kelts held in freshwater and exposed from late December 1986 to a simulated natural photoperiod (NP) and a regime of two 6-mo seasonally accelerated light increases and decreases (2CP) reconditioned. Fifty-six percent of NP females spawned by early November 1987, 1 mo later than virgin wild females. No 2CP females spawned by December 1987. However, all 2CP females transferred in December 1987 to natural photoperiod and 7 °C water released eggs by June 1988. NP females that spawned showed seasonal peaks in cholesterol in August, triglycerides and calcium in September, and alkaline phosphatase in November; NP and 2CP females that failed to spawn showed no such changes. Alkaline phosphatase activity and calcium concentrations were linearly related to increasing oocyte diameter (but not oocyte number), and were good predictors of sex and oocyte development. Forty-two percent of 2CP males matured and released sperm in mid-August, 1 mo earlier than NP males or a virgin wild group. Twenty-three percent of 2CP males did not mature. Males showed significant differences in blood parameters between regimes and between spawners and nonspawners, but the levels were never as high as maturing females.
Virus-Like Particles in an Ultra-Oligotrophic Lake on Vancouver Island, British Columbia
Authors: Klut M. Emilia , Stockner John G.
Published: November 2008

Transmission electron microscopy (TEM) seasonal studies of concentrated water samples from Sproat Lake, Vancouver Island, British Columbia, revealed numerous polygonal virus-like particles of variable size (60–200 nm). These particles (ca. 107/mL) were either free-living or associated with host picoplankters. Negative staining of living samples provides clear evidence of early stages of phage–picoplankton interactions. These phages display a six-sided head (ca. 90 nm dia.) with a distinct appendage (ca. 200 nm) or striated tail (ca. 130 nm). Viruses with dense matrices, deprived of envelopes or occurring as empty shells were found in the marginal area of invaded cells. Morphological changes such as invagination of the photosynthetic lamellae with the appearance of 'virogenic stroma' or with disruption of the cell membrane and the cell wall are described. Comments on the possible functional significance of viral agents in the biology and ecology of host cells are presented.
Serum Lipoproteins in Striped Bass (Morone saxatilis): Effects of Starvation
Authors: MacFarlane R. Bruce , Harvey H. Rodger , Bowers Michael J. , Patton John S.
Published: November 2008

Withholding food for 4 wk resulted in more extensive alterations within serum lipoprotein classes in striped bass (Morone saxatilis) than were evident in serum total lipids where only a decrease in triglycerides was significant. Total serum lipoprotein concentrations were about 3300 mg/dL in both fed and starved fish; however, high density lipoproteins (HDL) increased and very low density lipoproteins (VLDL) decreased significantly in the starved group. Quantitatively, the greatest changes in VLDL, the primary transporter of triglycerides, were declines in triglycerides and cholesterol esters. Within low density lipoproteins, triglycerides and phospholipids decreased. The HDL composition was affected least by starvation. Phospholipids were the dominant lipid in HDL and increased from 479.1 mg/dL in fed to 670.2 mg/dL in starved fish. The apoproteins of each lipoprotein class changed little qualitatively due to starvation. Our results reflect the importance of maintaining high levels of lipoproteins as a transport system for lipids from storage depots to depleted tissues permitting survival during prolonged periods of starvation that are often encountered by fish during colder months and during spawning migrations. Furthermore, during starvation HDL appears to assume increased significance as a vehicle for the transport of structural lipids to maintain tissue integrity.