bluuebunny/crossref_metadata_2025 huggingface dataset:
Cold agglutinin syndrome in pediatric liver transplant recipients
Authors: Wong Wendy , Merker Jason D. , Nguyen Christine , Berquist William , Jeng Michael , Viele Maurene , Glader Bertil , Fontaine Magali J.
Published: September 2007

Abstract:  Anemia is a common finding in post‐liver transplant patients. Causes for the anemia include nutritional deficiencies, red cell aplasia as well as immune‐mediated hemolysis. One of the immunologic causes of hemolytic anemia is drug‐induced hemolysis. Tacrolimus is a common immunosuppressant used in post‐liver transplant patients to prevent graft rejection. There have been reports of tacrolimus‐associated hemolytic anemia secondary to hemolytic uremic syndrome as well as autoimmune hemolysis. There are also case‐reports of severe hemolytic anemia related to cold agglutinin production in post‐liver transplant patients. We described in this paper three cases of severe cold agglutinin hemolytic anemia in three pediatric liver transplant patients. Steroid therapy, plasmapheresis and withdrawal of tacrolimus led to resolution of the severe hemolytic process in each case. Whether the immune‐mediated hemolysis is related to tacrolimus is not clear and needs to be characterized further.
Effect of Norgestomet Treatment on Plasminogen Activator Activity in the Cervical Mucus and the Endometrium in Dairy Cows
Authors: Bargouli G. G. , Tsantarliotou M. P. , Brozos C. N. , Kokolis N. A. , Boscos C. M.
Published: September 2007

The aim of this study was to determine the effect of norgestomet treatment, in the absence or the presence of a functional corpus luteum (CL), on plasminogen activators activity (PAA) in the cervical mucus and the endometrium in dairy cows. Eleven days after oestrus (Day 0 = oestrus), 38 cows were randomly assigned to one untreated control group (n = 9) and three treatment groups (S1, S2and S3). Animals of S1group (n = 9) received an implantation of norgestomet on the outer surface of the ear for 8 days, simultaneous injection of oestradiol valerate 5 mg and norgestomet 3 mg, i.m., and on Day 19 an injection of ECG 500 IU, i.m. Animals of S2group (n = 11) received the treatment of S1group, plus an administration of PGF2α on Day 10 for the regression of CL. Animals of S3group received the treatment of S2group, plus two additional norgestomet implants inserted on Day 16 for 36 h. Both types of plasminogen activators [the tissue‐type (t‐PA) and the urokinase‐type (u‐PA)] were detected in the cervical mucus and the endometrium of the cows. Plasminogen activators activity in the cervical mucus was higher in control group than in S1, S2and S3groups (P < 0.001). In contrast, endometrial PAA did not differ among groups (P > 0.05). Oestradiol‐17β concentrations on Day 21 were higher in S2group than in control group (P < 0.01) and S3group (P < 0.05). Progesterone concentrations did not differ among groups (P > 0.05). Oestradiol‐17β concentrations could positively affect cervical mucus PAA in control group (P < 0.1), but not in other groups (P > 0.05). These findings suggest that control of estrous cycle by norgestomet administration, in dairy cows, exerts a suppressive effect on plasminogen activators synthesis and/or secretion in the cervical mucus, regardless of the absence or the presence of the CL. On the contrary, endometrial PAA is not affected by norgestomet treatment.
Expression of Peroxisome Proliferator‐activated Receptor Gamma (PPAR‐γ) in Canine Nasal Carcinomas
Authors: Paciello O. , Borzacchiello G. , Varricchio E. , Papparella S.
Published: September 2007

Peroxisome proliferator‐activated receptor γ (PPAR‐γ) is a ligand‐activated transcriptional factor belonging to the steroid receptor superfamily. PPAR‐γ is expressed in multiple normal and neoplastic tissues, such as the breast, colon, lung, ovary and placenta. In addition to adipogenic and anti‐inflammatory effects, PPAR‐γ activation has been shown to be anti‐proliferative by its differentiation‐promoting effect, suggesting that activation of PPAR‐γ may be useful in slowing or arresting the proliferation of de‐differentiated tumour cells. In this study, we investigated the expression of PPAR‐γ in normal and neoplastic canine nasal epithelium. Twenty‐five samples composed of five normal nasal epithelia and 20 canine nasal carcinomas, were immunohistochemically stained for PPAR‐γ. The specificity of the antibody was verified by Western Blot analysis. Confocal laser scanning microscopical investigation was also performed. In normal epithelium, the staining pattern was cytoplasmic and polarized at the cellular free edge. In carcinomas, the neoplastic cells showed mainly strong cytoplasmatic PPAR‐γ expression; moreover, perinuclear immunoreactivity was also detected and few neoplastic cells exhibited a nuclear positivity. Our results demonstrate different patterns of PPAR‐γ expression in normal canine nasal epithelium when compared with canine nasal carcinoma. The importance of this transcription factor in the pathophysiology of several different tumours has stimulated much research in this field and has opened new opportunities for the treatment of the tumours.
Analysis of the Canine mdr1−1Δ Mutation in the Dog Breed Elo
Authors: Fecht S. , Wöhlke A. , Hamann H. , Distl O.
Published: September 2007

A deletion mutation in the canine multidrug resistance gene, MDR1, is associated with drug sensitivity. This was shown for several purebred dog breeds from the Collie lineage such as the Collie (rough‐coated and smooth‐coated), the Australian Shepherd and the Old English sheepdog. To determine whether the mdr1−1Δ mutation could be found in the newly bred German dog breed Elo which is based amongst other breeds on Old English sheepdogs, 177 blood samples representative for the Elo breed were collected. After DNA extraction, a polymerase chain reaction‐based method with subsequent polyacrylamide gel electrophoresis was used for detection of the mdr1−1Δ mutation. The mdr1−1Δ allele was not observed in the Elos investigated. The probability that the mdr1−1Δ allele originated in the Old English sheepdog breed is segregating in the Elo population was estimated at 3.68 × 10−17.
Incretin‐based treatment of type 2 diabetes: glucagon‐like peptide‐1 receptor agonists and dipeptidyl peptidase‐4 inhibitors*
Authors: Deacon Carolyn F.
Published: September 2007

Incretins are gut peptides that potentiate nutrient‐stimulated insulin secretion following meal ingestion. Activities of the dominant incretins, glucagon‐like peptide‐1 (GLP‐1) and glucose‐dependent insulinotropic peptide, include glucose‐dependent stimulation of insulin secretion and, in preclinical models, improvement in islet β‐cell mass. GLP‐1 additionally reduces glucagon secretion, inhibits gastric emptying and promotes satiety. Patients with type 2 diabetes mellitus (T2DM) exhibit reduced total and intact GLP‐1 levels, and exogenous administration of the hormone via continuous infusion results in glucose profiles similar to those in non‐diabetic subjects. Incretins are rapidly degraded by dipeptidyl peptidase‐4 (DPP‐4). Thus, strategies to enhance incretin activity have included development of GLP‐1 receptor agonists resistant to the action of DPP‐4 (e.g. exenatide and liraglutide) and DPP‐4 inhibitors that act to increase concentrations of endogenous intact incretins (e.g. sitagliptin and vildagliptin). Clinical trials of these incretin‐based therapies have shown them to be effective in improving glycaemic control in patients with T2DM.
Childhood disruptive behaviors and family functioning in clinically referred children: Are girls different from boys?
Authors: FOSSUM STURLA , MØRCH WILLY‐TORE , HANDEGÅRD BJØRN HELGE , DRUGLI MAY BRITT
Published: September 2007

Baseline assessments of 4 to 8‐year‐old children, 26 girls and 101 boys, referred to outpatient treatment for disruptive behaviors, were examined, focusing on possible differences between the functioning of boys and girls and their families. Child variables included diagnostic information, measures of disruptive behaviors, social competence, and independent observations of child behaviors. A variety of family variables, such as information regarding parenting practices, parental stress, and depression were included. Teacher reports of disruptive behaviors and social competence at school were included. Teacher ratings of child functioning indicated that boys displayed significantly more externalizing behaviors and they were less socially competent than girls. Parents perceived both girls and boys as highly oppositional and aggressive, and generally speaking, differences were few. Nevertheless, the level of stress was higher in girls’ than in boys’ families, and mothers of girls reported of higher levels of depressive symptoms. Girls and boys did not differ regarding diagnostic status.
Intercellular adhesion molecule‐1 gene polymorphism in Iranian patients with multiple sclerosis
Authors: Mousavi S. A. R. , Nikseresht A. R. , Arandi N. , Borhani Haghighi A. , Ghaderi A.
Published: September 2007

Intercellular adhesion molecule‐1 (ICAM‐1), an important molecule in leucocyte activation and migration, is expressed on the CNS endothelial cells of patients with multiple sclerosis. This study was conducted to determine whether ICAM‐1 gene polymorphism influences the risk of developing multiple sclerosis in an Iranian population. We studied 157 patients with definite multiple sclerosis and 156 ethnically matched controls. The patients and the controls were genotyped for ICAM‐1 gene polymorphism at codons 241 (exon 4) and 469 (exon 6). G/R241 and K/E 469 allele and genotype distribution did not show any significant difference between patient and control groups. We concluded that role of the ICAM‐1 gene polymorphisms in the pathogenesis of multiple sclerosis is still controversial and should be studied further.
Willingness of gynaecologists, doctors in family planning, GPs, practice nurses and pharmacists to adopt novel interventions for treating sexual partners of women with chlamydia
Authors: Cameron ST , Melvin L , Glasier A , Scott G , Johnstone A , Young H
Published: September 2007

Objective  To determine willingness of health professionals to adopt new interventions for treating sexual partners of women with chlamydia.

Design  Anonymous, self‐administered questionnaires of doctors, practice nurses and community pharmacists regarding novel testing/treatment options for partners of women with chlamydia.

Setting  Local (Scotland) and national (UK) clinical meetings in reproductive health, and community pharmacy (Lothian).

Population  Doctors (general practice, gynaecology, family planning) and practice nurses who were delegates at selected meetings in reproductive health and community pharmacists attending pharmacy meetings.

Methods  Doctors and nurses were invited to complete a questionnaire indicating their preferred strategy for testing/treating sexual partners of women with chlamydia if given choice of partner notification, postal testing kit (PTK), patient delivered partner medication (PDPM) with azithromycin or combined PDPM and PTK. Community pharmacists were invited to complete a questionnaire regarding their willingness to introduce chlamydia testing and treatment services.

Main outcome measures  Reported preferences of doctors and nurses for partner testing/treatment strategies and willingness of pharmacists to offer new services.

Results  Questionnaires were completed by 211 doctors, 73 practice nurses and 50 pharmacists. The most popular choice of doctors (30%) and nurses (23%) was a combination of PDPM with PTK, with partner notification the least popular (8 and 3%, respectively). One in four doctors had previously used PDPM for treating partners. Most pharmacists were willing to supply free PTKs (98%), offer testing (75%) and treatment services (100%) and give women PDPM for partners (80%).

Conclusion  Relevant health professionals, who are increasingly involved in managing chlamydia, are largely in favour of introducing new strategies for treating sexual partners.
Dinophysis diegensis is a life history stage of Dinophysis caudata (Dinophyceae, Dinophysiales)1
Authors: Reguera Beatriz , González‐Gil Sonsoles , Delgado Maximino
Published: September 2007

Several species of Dinophysis Ehrenb. have been observed to produce “small cells” that are different in size and shape from the vegetative cells, following a reductionary division under certain environmental conditions, as part of a polymorphic life cycle. Based on observations on fixed field samples, D. diegensis Kof. was hypothesized to be a small form of D. caudata Saville‐Kent. In this study, this hypothesis was confirmed after incubations, in cell culture chambers, of groups of individually picked vegetative cells from natural populations of D. caudata. Eight to 10 d after inoculation, different life‐cycle stages were observed in the wells. Illustrations of small and intermediate forms of D. caudata developed in vitro were contrasted with those observed during their proliferation in the northeast Atlantic (Galicia) and northwest Mediterranean (Catalonia) coasts of Iberia. It is proposed that Dinophysis diegensis–like specimens should be considered as a taxonomic (or heterotypic) synonym of Dinophysis caudata. A historical overview is provided (see Supplementary material) that revises the large list of taxa used to nominate different morphotypes of D. caudata, and its small and intermediate cells, since its original description by Saville‐Kent in 1881.
Changes in Ventricular Dimensions and Function During Recovery of Atrial Tachycardia‐Induced Cardiomyopathy Treated with Catheter Ablation
Authors: ILKHANOFF LEONARD , GERSTENFELD EDWARD P. , ZADO ERICA S. , MARCHLINSKI FRANCIS E.
Published: September 2007

A 25‐year‐old male with an atrial tachycardia‐induced cardiomyopathy (TIC) presented to our institution with clinical heart failure, an ejection fraction of 10%, and a severely dilated left ventricle. He underwent successful ablation and had no recurrence of this arrhythmia. In this report, we document the acute and long‐term follow‐up (out to 10 years) of a single patient with a TIC and present the changes in left ventricular (LV) function and dimensions that occurred. Despite the apparent success of ablative therapy, this case report highlights the importance of routine clinical and echocardiographic follow‐up in patients with longstanding TIC.
Differences between subtypes of children with ADHD and simple attentional difficulties during an initial assessment
Authors: Weber Peter , Jourdan‐Moser Sonya , Halsband Ulrike
Published: September 2007

Objective: To examine differences between subtypes of children with attention‐deficit/hyperactivity disorder (ADHD), simple attentional difficulties and situational ADHD during an initial assessment.

Method: In a single‐centre study examination data of 205 children who had an initial assessment between January 1, 2002 and December 31, 2003 were retrospectively analyzed. The groups of children were compared with respect to their history features, neuromotor deficits, neuropsychological performance, and comorbid behavioural and developmental deficits by standardized test procedures and questionnaires.

Results: Children with ADHD more frequently have a positive family history of attentional symptoms than non‐ADHD children. There is no difference between these groups with respect to the associated behavioural problems. Children classified as ADHD show more neuromotor problems and neuropsychological deficits than children with non‐ADHD attentional problems. Children with ADHD subtype hyperactive/impulsive demonstrate better neuropsychological performance than children with subtypes inattentive and combined. Children with situational home‐only or school‐only ADHD show no clear differences in neuromotor behaviour, comorbid problems or neuropsychological performance.

Conclusions: There are clear neuropsychological differences between children who fulfil the classification criteria of The Diagnostic and Statistical Manual of Disease, Fourth Revision (DSM‐IV) for ADHD and children who are confronted daily with attentional difficulties, but do not fulfil the criteria for ADHD. In contrast, differences in behavioural comorbidities were not found, nor were differences found between home‐only and school‐only ADHD children.
Importance of T Cells, Gamma Interferon, and Tumor Necrosis Factor in Immune Control of the Rapid GrowerMycobacterium abscessusin C57BL/6 Mice
Authors: Rottman Martin , Catherinot Emilie , Hochedez Patrick , Emile Jean-François , Casanova Jean-Laurent , Gaillard Jean-Louis , Soudais Claire
Published: September 2007

Mycobacterium abscessusis an emerging rapidly growing mycobacterium that causes tuberculous-like lesions in humans. We studied the immune control of this organism in C57BL/6 mice challenged intravenously with 107CFU. Bacteria were eliminated from both the spleen and the liver within 90 days, and liver histology showed organized granulomatous lesions. A T- and B-cell requirement was investigated by challengingRag2−/−,Cd3ε−/−, and μMT−/−mice.Rag2−/−andCd3ε−/−mice were significantly impaired in the ability to clearM. abscessusfrom the liver and spleen, and μMT−/−mice were significantly impaired in the ability to clearM. abscessusfrom the liver, suggesting that infection control was primarily T cell dependent in the spleen and both T and B cell dependent in the liver. The liver granulomatous response was similar to that of wild-type controls in μMT−/−mice but completely absent inCd3ε−/−andRag2−/−mice. We studied the involvement of gamma interferon (IFN-γ) and tumor necrosis factor (TNF) by challenging C57BL/6 mice deficient in the IFN-γ receptor (Ifngr1−/−) and in TNF (Tnf−/−).Ifngr1−/−mice were significantly impaired inM. abscessuscontrol both in the spleen and in the liver, and granulomas were profoundly altered. The effect was even more substantial inTnf−/−mice; they failed to controlM. abscessusinfection in the liver and died within 20 to 25 days after infection with many hepatic inflammatory foci and major lesions of ischemic necrosis in the liver and kidney. These features were not observed with the closely related speciesM. chelonae. T-cell immunity, IFN-γ, and TNF are central factors for the control ofM. abscessusin C57BL/6 mice, as they are for the control of pathogenic slowly growing mycobacteria.
LAW FIRMS & THE LIFE SCIENCES SECTOR IN AUSTRALIA
Authors: Solakovski Jackie
Published: September 2007

This article is about the relationship of law firms and the life sciences sector in Australia. It discusses about an example of a law firm, Lander & Rogers Lawyers and the life sciences sector in Australia.
Asian Biotechnology Hub
Authors: Muralitharan Morley
Published: September 2007

The article summarises Asia as a biotechnology hub focusing on Singapore, Taiwan, Malaysia, India, Japan, China, Hong Kong, South Korea, Sri Lanka and Thailand. It describes how Asia is one of the more attractive locations for global biotechnology companies to invest in highly skilled staff and world class technologies.
The National Biotechnology Policy: New Opportunites for Biotechnology in Malaysia
Authors: Quah Soon-Cheang , Arujanan Mahaletchumy
Published: September 2007

The article discusses about the National Biotechnology policy and the biotechnology industry in Malaysia. It talks about the incentives and grants that the Malaysian government has for their investors and researchers. It also states the factors why investors should consider Malaysia as a country they can invest in.
Alternative Medicine
Authors: Tsim Karl W. K. , Li Shao P.
Published: September 2007

Cordyceps sinensis—a Traditional Chinese Medicine Known as Winter-worm Summer-grass.
Fault Characterization and Testability Analysis ofEmitter Coupled Logic and Comparison with CMOS& BiCMOS Circuits
Authors: Esonu M. O. , Al-Khalili D. , Rozon C.
Published: September 2007

The logic behavior and performance of ECL gates under a set of defect models are examined. These are compared
with equivalent set of BiCMOS and CMOS gates. It is found that logical fault testing is inadequate for obtaining
a sufficiently high fault coverage, e.g., 79% for ECL versus 54% for BiCMOS and 69% for CMOS equivalent
gates. Performance degradation faults such as delay, current and Voltage Transfer Characteristics (VTC) or Noise
Margin (NM) faults are analyzed as applied to these gates. It is shown that logical fault testing with delay fault
testing yields the highest fault coverage for BiCMOS and CMOS gates (around 95%). However, for equivalent
ECL gates to attain a fault coverage of around 98%, both logical and NM fault testing have to be used.
Cell Generator‐Based Technology Mappingby Constructive Tree‐Matchingand Dynamic Covering
Authors: Lefebvre Martin , Liem Cliff
Published: September 2007

Technology mapping is the final step of logic synthesis which consists of mapping an optimized technology
independent logic network representation into a circuit realization in a given technology. An important component
of the technology mapping problem is the identification of feasible library cells for the realization of the logic
operators in the logic tree. There are two main classes of such matching algorithms. Library‐based matching
algorithms [1–4] require that all available physical components be represented explicitly in a pattern library.
Sections of the logic network are then matched against this pattern list for the identification of suitable
components. In contrast, cell generator‐based matching techniques [6–8] accept feasibility constraints on the
complexity and quantity of physical components according to limits imposed by the target technology or the
capabilities of the cell generator. Hence, individual patterns are not stored in a library and are instead generated
as needed. In this paper, we present a new cell generator‐based constructive matching algorithm. Because the
algorithm builds matched patterns incrementally, very large cell families can be accommodated using time and
space resources that are proportional to the size of the largest feasible cell pattern and not the size of the library
of patterns as would be the case for library‐based approaches. Also, whereas existing cell generator‐based
matching techniques combine the tasks of matching (identification) and covering (selection), constructive matching
provides more flexibility by not restricting the covering phase. Empirical results demonstrate the increased quality
of the technology‐mapped circuits when larger cells are available.
An ILP Solution for Optimum Scheduling, Moduleand Register Allocation, and OperationBinding in Datapath Synthesis
Authors: Wilson T. C. , Mukherjee N. , Garg M. K. , Banerji D. K.
Published: September 2007

We present an integrated and optimal solution to the problems of operator scheduling, module and register
allocation, and operator binding in datapath synthesis. The solution is based on an integer linear programming
(ILP) model that minimizes a weighted sum of module area and total execution time under very general
assumptions of module capabilities. In particular, a module may execute an arbitrary combination of operations,
possibly using different numbers of control steps for different operations. Furthermore, operations may be
implemented by a variety of modules, possibly requiring different numbers of control steps depending on the
modules chosen. This generality in the complexity and mixture of modules is unqiue to our system and leads to an
optimum selection of modules to meet specified design constraints. Significant extensions include the ability to
incorporate pipelined functional units and operator chaining in an integrated manner. Straightforward extension
to multi‐block synthesis is discussed briefly but the details are omitted due to space considerations.
Performance and Area Optimization of VLSISystems Using Genetic Algorithms
Authors: Wang Xiao-Dong , Chen Tom
Published: September 2007

A new performance and area optimization algorithm for complex VLSI systems is presented. It is widely believed
within the VLSI CAD community that the relationship between delay and silicon area of a VLSI chip is convex.
This conclusion is based on a simplified linear RC model to predict gate delays. In the proposed optimization
algorithm, a nonlinear, non‐RC based transistor delay model was used which resulted in a non‐convex relationship
between the delay and the silicon area of a VLSI chip. Genetic algorithms are better suited for discrete,
non‐convex, non‐linear optimization problems than traditional calculus‐based algorithms. By using the genetic
algorithms in the performance and area optimization, we are able to find the optimal values for both delay and
silicon area for the ISCAS benchmark circuits.
A Comparison of Bit Serialand Bit Parallel DCT Designs
Authors: Crook David , Fulcher John
Published: September 2007

Bit parallel and bit serial VLSI designs for performing 1‐dimensional Discrete Cosine Transforms are compared,
in terms of size, complexity and throughput. It is concluded that the bit serial approach is more suited to this
application, given the limitations of not only the available VLSI design tools, but also the available silicon real
estate allocated for final chip fabrication.
An Integrated Hardware Array for Very High Speed Logic Simulation
Authors: Fehr E. Scott , Szygenda Stephen A. , Ott Granville E.
Published: September 2007

A hardware architecture is proposed which allows direct mapping of design simulation topology onto an acceleration platform. In order to clarify architectural principles, the simulation is confined to functional verification of unit delay, binary valued gate level logic designs. Under this approach, a rank ordered design description is executed on a massively parallel processor grid which implements an efficient and direct model of the design, similar to prototyping. Architectural innovation reduces logic complexity and execution time of
boolean evaluation and fanout switching circuits, while large scale parallelism is integrated at die level to reduce cost and communication delays. The results of this research form the basis for a multiple order of magnitude improvement in reported state‐of‐the‐art cost‐performance merit for hardware gate level simulation accelerators.
The Use of Field‐Programmable Gate Arrays for the Hardware Acceleration of Design Automation Tasks
Authors: Howard Neil J. , Tyrrell Andrew M. , Allinson Nigel M.
Published: September 2007

This paper investigates the possibility of using Field‐Programmable Gate Arrays (Fpgas) as reconfigurable co‐processors for workstations to produce moderate speedups for most tasks in the design process, resulting in a worthwhile overall design process speedup at low cost and allowing algorithm upgrades with no hardware modification. The use of Fpgas as hardware accelerators is reviewed and then achievable speedups are predicted for logic simulation and VLSI design rule checking tasks for various Fpga co‐processor arrangements.
Zener Zap Anti‐Fuse Trim in VLSI Circuits
Authors: Comer Donald T.
Published: September 2007

This paper presents an overview of Zener zap anti‐fuse trim as used to achieve improved
accuracy in precision integrated circuits. Because this technology spans design and manufacturing,
elements of design, layout, processing, and testing are included. The mechanism is
defined and typical applications are discussed. Layout considerations of anti‐fuse devices are
summarized and complex trim networks and multiplexed control methods are presented.
Both bipolar and CMOS process implementations are considered. The paper also contains a
bibliography which includes U.S. patents, which make up a large part of the technical
documentation of this technology.
Hardware Design Rule Checker Using a CAM Architecture
Authors: Kim Seokjin , Sridhar Ramalingam
Published: September 2007

This paper presents a hardware implementation of design rule checker using a specialized Content Addressable Memory(CAM) for the Manhattan geometric designs. Two dimensional relationships between rectangular objects in a design are checked with one dimensional design rules. The input data is processed by the pixel pre‐processor in such a way that direct comparison between the input data and the stored rules in the CAM is possible. The comparison by the CAM reduces the number of memory references and logic operations of pattern matching and the simple architecture of the system enables a low cost implementation.
PGEN: A Novel Approach to Sequential Circuit Test Generation
Authors: Jone Wen-Ben , Shah Nigam , Gleason Anita , Das Sunil R.
Published: September 2007

A novel approach, called PGEN, is proposed to generate test patterns for resettable or nonresettable synchronous sequential circuits. PGEN contains two major routines, Sequential PODEM (S‐PODEM) and a differential fault simulator. Given a fault, S‐PODEM uses the concept of multiple time compression supported by a pulsating model, and generates a test vector in a single (yet compressed) time frame. Logic simulation (included in S‐PODEM) is invoked to expand the single test vector into a test sequence. The single test vector generation methodology and logic simulation are well coordinated and significantly facilitate sequential circuit test generation. A modified version of differential fault simulation is also implemented and included in PGEN to cover other faults detected by the expanded test sequence. Experiments using computer simulation have been conducted, and results are quite satisfactory.
A Methodology for Testing Arbitrary Bilateral Bit‐Level Systolic Arrays
Authors: Bandyopadhyay S. , Sengupta A. , Bhattacharya B. B.
Published: September 2007

In this paper, we discuss the controllability and observability issues in bilateral bit‐level systolic arrays. We have introduced a new concept—‘Sj‐controllability in M steps’, which is somewhat analogous to the concept of C‐testability and refers to the fact that all the cells in the array can be set to the state Sj
in at most M steps after initialization. Systolic arrays where the value of M is independent of the length, of the array are characterized. Our testing procedure is based on partitioning the array into several identical subarrays which allows us to apply a repetitive pattern of tests and propagate test outcome to the observable extremities so that every cell in the array is tested by a minimum sequence of tests. Based on this concept,we have developed a set of sufficient conditions for an arbitrary bilateral bit‐level systolic array to be testable for single faults.
Open Problems in Quantum Simulationin Ultra‐Submicron Devices
Authors: Ferry D. K. , Barker J. R.
Published: September 2007

Quantum transport is becoming more significant as device size shrinks. For example, as
device sizes are scaled below 0.1 μm, the number of impurities becomes quite small, so
that they are no longer homogeneously distributed throughout the device volume and
the carriers are localized into quantum boxes, in that self‐energy corrections produced by
locally high carrier densities will lead to quantum dot formation. This leads to the need
to discuss transport through an array of such quantum structures. Here, we discuss
several issues which must be considered in treating the transport through such devices.
Study on Possible Double Peaks in CutoffFrequency Characteristics of AlGaAs/GaAsHBTs by Energy Transport Simulation
Authors: Okada T. , Horio K.
Published: September 2007

By using an energy transport model, we simulate cutoff frequency fT  versus collector
current density IC characteristics of npn−n AlGaAs/GaAs heterojunction bipolar
transistors (HBTs) with various n−‐collector thickness and n−‐doping densities. It is
found that the calculated fT  characteristics show double peak behavior when the n−‐
layer is thick enough and the n−‐doping is high enough to allow existence of neutral n−‐
region. The mechanism of the double peak behavior is discussed by studying energy
band diagrams, electron‐energy profiles and electron‐velocity profiles. Particularly, we
discuss the origin of the second peak (at higher IC) which is not usually reported
experimentally.
Complete RF Analysis of Compound FETs Basedon Transient Monte Carlo Simulation
Authors: Babiker S. , Asenov A. , Cameron N. , Beaumont S. P. , Barker J. R.
Published: September 2007

In this paper we described a complete methodology to extract the RF performance of
‘real’ compound FETs from time domain Ensemble Monte‐Carlo (EMC) simulations
which can be used for practical device design. The methodology is based on transient
finite element EMC simulation of realistic device geometry. The extraction of the
terminal current is based on the Ramo‐Shockley theorem. Parasitic elements like the
gate and contact resistances are included in the RF analysis at the post‐processing stage.
Example of the RF analysis of pseudomorphic HEMTs illustrates our approach.
Quantum Networks: Dynamics of Open Nanostructures
Authors: Mahler Günter , Wawer Rainer
Published: September 2007

The superposition principle makes quantum networks behave very differently from their
classical counterparts: We discuss how local and non‐local coherence are generated and
how these may affect the function of composite systems. Numerical examples concern
quantum trajectories, quantum noise and quantum parallelism.
Numerical Simulation of Heat Removalfrom Low Dimensional Nanostructures
Authors: Mitin V. V. , Bannov N. A. , Mickevičius R. , Paulavičius G.
Published: September 2007

The acoustic phonon radiation patterns and acoustic phonon spectra due to electron acoustic
phonon interaction in double barrier quantum well have been investigated by solving both the
kinetic equations for electrons and phonons. The acoustic phonon radiation patterns have
strongly pronounced maximum in the directions close to the perpendicular to the quantum
well direction. The radiation pattern anisotropy is explained in terms of possible electron transitions,
nonequilibrium electron distribution function, and the Hamiltonian of electron‐phonon
interactions.
Electron‐LA Phonon Interaction in a Quantum Dot
Authors: Ezaki T. , Mori N. , Hamaguchi C.
Published: September 2007

Relaxation time due to electron‐longitudinal‐acoustic (LA) phonon interaction is
calculated in a GaAs quantum dot (QD) with N electrons (from N = 1 to 4), where
electrons in a narrow quantum well are confined by a parabolic confining potential, by
using the exact eigen states of electrons. Although the energy levels become dense with
increasing the number of electrons, the modification of the relaxation time is found to be
not so strong, which attributes the fact that many electron eigen states consist of only a
few dominant single electron states which limit the electron relaxation. By comparing
relaxation process via intermediate states with the direct process, several fastest
processes are found to be realized by relaxation through intermediate states between the
initial state and the ground state. The effect of change in the quantum well width is also
discussed.
Quantum Transport Simulation of the DOS function, Self‐Consistent Fields and Mobility in MOS Inversion Layers
Authors: Vasileska Dragica , Eldridge Terry , Bordone Paolo , Ferry David K.
Published: September 2007

We describe a simulation of the self‐consistent fields and mobility in (100) Si‐inversion layers
for arbitrary inversion charge densities and temperatures. A nonequilibrium Green′s functions
formalism is employed for the state broadening and conductivity. The subband structure of
the inversion layer electrons is calculated self‐consistently by simultaneously solving the
Schrödinger, Poisson and Dyson equations. The self‐energy contributions from the various
scattering mechanisms are calculated within the self‐consistent Born approximation. Screening
is treated within RPA. Simulation results suggest that the proposed theoretical model
gives mobilities which are in excellent agreement with the experimental data.
Applicability of the High Field Model:An Analytical Study Via Asymptotic ParametersDefining Domain Decomposition
Authors: Cercignani Carlo , Gamba Irene M. , Jerome Joseph W. , Shu Chi-Wang
Published: September 2007

In this paper, we present a mesoscopic‐macroscopic model of self‐consistent charge
transport. It is based upon an asymptotic expansion of solutions of the Boltzmann
Transport Equation (BTE). We identify three dimensionless parameters from the BTE.
These parameters are, respectively, the quotient of reference scales for drift and thermal
velocities, the scaled mean free path, and the scaled Debye length. Such parameters
induce domain dependent macroscopic approximations. Particular focus is placed upon
the so‐called high field model, defined by the regime where drift velocity dominates
thermal velocity. This model incorporates kinetic transition layers, linking mesoscopic
to macroscopic states. Reference scalings are defined by the background doping levels
and distinct, experimentally measured mobility expressions, as well as locally
determined ranges for the electric fields. The mobilities reflect a coarse substitute for
reference scales of scattering mechanisms. See [9] for elaboration.

The high field approximation is a formally derived modification of the augmented
drift‐diffusion model originally introduced by Thornber some fifteen years ago [25]. We
are able to compare our approach with the earlier kinetic approach of Baranger and
Wilkins [5] and the macroscopic approach of Kan, Ravaioli and Kerkhoven [20].
Single‐Electron Parametron
Authors: Likharev Konstantin K. , Korotkov Alexander N.
Published: September 2007

We have suggested a novel family of wireless single‐electron digital devices, based on the
parametric excitation principle. The basic cell is a short array of small conducting islands separated
by tunnel barriers with relatively low capacitance and conductance. External rf (clock)
field creates conditions for spontaneous breaking of the charge symmetry of the cell. The
symmetry may be broken by the signal field provided by the neighboring cell(s). This mode
ensures robust operation of the parametron‐based logic circuits. Moreover, these devices may
be reversible, dissipating energy well below kBT 1n2 per logic operation.
Simulation of Bistable Laser Diodeswith lnhomogeneous Excitation
Authors: Fang Gang , Tang Ting-Wei
Published: September 2007

A comprehensive time‐dependent 1‐D computer model is developed for the simulation
of multi‐section bistable laser diodes. Analysis of a Fabry‐Perot (FP) cavity laser diode
indicates that the height and shape of the optical input pulse as well as the wavelength
play important roles in the set/reset operation of optical switching.
Three‐Dimensional Hydrodynamic Modelingof MOSFET Devices
Authors: Kerr Daniel C. , Goldsman Neil , Mayergoyz Isaak D.
Published: September 2007

The hydrodynamic (HD) model of semiconductor devices is solved numerically in
three‐dimensions (3‐D) for the MOSFET device. The numerical instabilities of the HD model
are analyzed to develop a stable discretization. The formulation is stabilized by using a new,
higher‐order discretization for the relaxation‐time approximation (RTA) term of the
energy‐balance (EB) equation. The developed formulation is used to model the MOSFET.
Study of Electron Velocity Overshoot in NMOSInversion Layers
Authors: Shih Wei-Kai , Jallepalli Srinivas , Rashed Mahbub , Maziar Christine M. , Tasch Al. F.
Published: September 2007

Non‐local electron transport in nMOSFET inversion layers has been studied by Monte
Carlo (MC) simulations. Inversion layer quantization has been explicitly included in the
calculation of density of states and scattering rate for low‐energy electrons while bulk
band structure is used to describe the transport of more energetic electrons. For
uniform, high‐lateral field conditions, the effects of quantization are less pronounced
due to the depopulation of electrons in the lower‐lying subbands. On the other hand,
Monte Carlo results for carrier transport in spatially varying lateral fields (such as those
in the inversion layer of MOSFETs) clearly indicate that depopulation of the low‐lying
subbands is less evident in the non‐local transport regime. Quasi‐2D simulations have
shown that, at high transverse effective field, the inclusion of a quantization domain
does have an impact on the calculated spatial velocity transient.
A Compound Semiconductor Process Simulator and itsApplication to Mask Dependent Undercut Etching
Authors: Kumagai Masami , Yokoyama Kiyoyuki , Tazawa Satoshi
Published: September 2007

This paper describes a process simulator that is designed to describe the etching and deposition
processes used in constructing compound semiconductors, which have at least two different
atomic species. This nature dictates a very different response to compound semiconductor
process from the silicon process. One of the most remarkable processes in compound semiconductors
is the reverse‐mesa formation. This simulator successfully represents the mesa
and the reverse mesa profiles that are often observed after chemical etching. The mask material
dependence of the undercut etching can also be simulated with a good agreement between
the experimental and the simulated shapes.
Monte Carlo Calibrated Drift‐Diffusion Simulationof Short Channel HFETs
Authors: Asenov A. , Babiker S. , Beaumont S. P. , Barker J. R.
Published: September 2007

In this paper we present a methodology to use drift diffusion (DD) simulations in the
design of short channel heterojunction FETs (HFETs) with well pronounced velocity
overshoot. In the DD simulations the velocity overshoot in the channel is emulated by
forcing the saturation velocity in the field dependent mobility model to values
corresponding to the average velocity in the channel obtained from Monte Carlo (MC)
simulation. To illustrate our approach we compare enhanced DD and MC simulation
results for a pseudomorphic HEMTs with 0.12 μm channel length, which are in good
agreement. The usefulness of the described methodology is illustrated in a simulation
example of self aligned gamma gate pseudomorphic HEMTs. The effect of the gamma
gate shape and the self aligned contacts on the overall device performance has been
investigated.
Modelling of Hot Acoustic Phonon Propagation in TwoDimensional Layers
Authors: Bannov N. A. , Mitin V. V. , Vasko F. T.
Published: September 2007

The transport of confined acoustic phonons in a flee‐standing quantum well has been studied
by solving the quantum kinetic equation for phonons. The phonon decay rate has been numerically
calculated for GaAs flee‐standing quantum well. Phonon interaction with electrons
through the deformation potential makes the major contribution to the acoustic phonon decay.
3D Parallel Finite Element Simulation of In‐Cell Breakdown in Lateral‐Channel IGBTs
Authors: Brown A. R. , Asenov A. , Barker J. R.
Published: September 2007

In this paper we describe the use of 3D parallel finite element solution of the Poisson
equation to calculate the in‐cell breakdown voltage in lateral channel IGBTs. The solver
is based on topologically rectangular grids, and uses a domain decomposition approach
to partition the problem on an array of mesh connected processors. A parallel
BiCGSTAB solver has been developed to solve the Possion equation. Hole and electron
ionisation integrals are calculated to determine the breakdown voltage. The effects of
varying the doping concentration in the n– base region and stopper surface
concentration are investigated.
Multiband Quantum Transmitting Boundary Methodfor Non‐orthogonal Basis
Authors: Liang G.-C. , Lin Y. A. , Ting D. Z.-Y. , Chang Y.-C.
Published: September 2007

We generalize the Multiband Quantum Transmitting Boundary Method (MQTBM) for
computing transmission coefficients in heterostructure to tight‐binding‐like band
structure models with non‐orthogonal basis and multiple neighbor interactions. We
implement this method based on the newly developed planar‐basis pseudopotential
method which uses the generalized planar Wannier function basis. We demonstrate the
method by computing transmission coefficients for a GaAs/AlAs double barrier
structure.
Tunneling Between Multimode Stacked Quantum Wires
Authors: Macucci M. , Galick A. T. , Ravaioli U.
Published: September 2007

Tunneling between vertically stacked quantum wires has been investigated. The wires
are assumed to have the dimension perpendicular to the tunneling barrier much smaller
than the other transverse dimension, so that only the lowest mode in such direction is to
be taken into account, while many modes in the other direction are filled. A model with
hard‐wall confinement has been used for the investigation of the transport problem, and
the tunneling conductance has been computed, via a recursive Green′s functions
procedure.
Lattice Effects in the Complex Subband Dispersion of 2DEG Semiconductor Waveguide Structures Subjected toa Perpendicular Magnetic Field
Authors: Edwards G. , Ferry D. K.
Published: September 2007

In modeling waveguide magneto‐transport experiments (in a quasi‐two dimensional electron
gas), it is important to have knowledge of the electronic states in a magnetic field perpendicular
to the plane of the waveguide confinement potential. We present numerical results, within
a lattice model, for the full complex subband dispersion of a rectangular waveguide. The form
of our numerical real‐subband solutions agrees well with analytical real solutions. However,
some of our numerical evanescent solutions have a different topology from the analytic evanescent
solutions near the bandedges. We argue that our evanescent solutions, although consistent
with the symmetry of the lattice model and mode conservation in the restricted Hilbert
space of the discretized Hamiltonian, yield different results that are forbidden in the continuum
solutions. This is a concern for numerical solutions.
A Hydrodynamic Model for Transportin Semiconductors without Free Parameters
Authors: Falsaperla P. , Trovato M.
Published: September 2007

We derive, using the Entropy Maximum Principle, an expression for the distribution
function of carriers as a function of a set of macroscopic quantities (density, velocity,
energy, deviatoric stress, energy flux). Given the distribution function, we obtain, for
these macroscopic quantities, a hydrodynamic model in which all the constitutive
functions (fluxes and collisional productions) are explicitely computed starting from
their kinetic expressions. We have applied our model to the simulation of some onedimensional
submicron devices in a temperature range of 77–300 K, obtaining results
comparable with Monte Carlo. Computation times are of order of few seconds for a
picosecond of simulation.
Quantum Distribution‐function Transport Equationsin Non‐normal Systems and in Ultra‐fast Dynamicsof Optically‐excited Semiconductors
Authors: Buot F. A.
Published: September 2007

The derivation of the quantum distribution‐function transport equations combines the
Liouvillian super‐Green′s function technique and the lattice Weyl‐Wigner formulation
of the quantum theory of solids. A generating super‐functional is constructed which
allows an algebraic and straightforward application of quantum field‐theoretical
techniques in real time to derive coupled quantum‐transport, condensate, and pairwavefunction
equations. In optically‐excited semiconductors, quantum distributionfunction
transport equations are given for phonons, plasmons, photons, and electron‐hole
pairs and excitons by transforming the Bethe‐Salpeter equation into a multi‐time
evolution equation. The virtue of quantum distribution function is that it allows easy
application of ‘device‐inflow’ subsidiary boundary conditions for simulating femtosecond
device‐switching phenomena.
Tutorial on VLSI Partitioning
Authors: Chen Sao-Jie , Cheng Chung-Kuan
Published: September 2007

The tutorial introduces the partitioning with applications to VLSI circuit designs. The
problem formulations include two‐way, multiway, and multi‐level partitioning, partitioning
with replication, and performance driven partitioning. We depict the models
of multiple pin nets for the partitioning processes. To derive the optimum solutions,
we describe the branch and bound method and the dynamic programming method
for a special case of circuits. We also explain several heuristics including the group
migration algorithms, network flow approaches, programming methods, Lagrange
multiplier methods, and clustering methods. We conclude the tutorial with research
directions.