bluuebunny/crossref_metadata_2025 huggingface dataset:
Homelessness among patients with schizophrenia in rural China: a 10‐year cohort study
Authors: Ran M. S. , Chan C. L.W. , Chen E. Y.H. , Xiang M.Z. , Caine E. D. , Conwell Y.
Published: February 2006

Objective:  To explore the frequency and risk factors of homelessness among a previously identified cohort of patients with schizophrenia in rural China.

Method:  A 10‐year follow‐up investigation among a 1994 cohort (n = 510) of patients with schizophrenia was conducted in Xinjin County, Chengdu, China.

Results:  Thirty‐nine patients (7.8%) experienced homelessness during the follow‐up period. The rate of homelessness was 0.9 per 100 person‐years during the 10‐year follow‐up period. Four significant predictors of homelessness remained in the final logistic regression model: living in shabby or unstable house or shelter, positive family history of mental disorders, without income of the patient, and unmarried, divorced, or separated. Risk of homelessness increased substantially with exposure to multiple risk factors.

Conclusion:  Substantial numbers of homeless patients with schizophrenia are challenges for mental health care and public health. Appropriate community‐based services, especially housing services, should be crucial for prevention of homelessness in patients with schizophrenia.
Cell‐mediated lysis of autologous platelets in chronic idiopathic thrombocytopenic purpura
Authors: Zhang Feng , Chu Xiaoxia , Wang Lin , Zhu Yuanyuan , Li Lizhen , Ma Daoxin , Peng Jun , Hou Ming
Published: February 2006

Abstract:  Objectives: Investigate the contribution and mechanism of cell‐mediated cytotoxicity to the pathogenesis of idiopathic thrombocytopenic purpura (ITP). Methods: We observed the cytotoxic effect of cytotoxic T‐lymphocyte (CTL) (CD8+) and natural killer cells (CD3−CD16+CD56+) toward chronic ITP patient's autologous platelets, and investigated the expression of Fas ligand (FasL), tumor necrosis factor (TNF)‐α and TNF‐related apoptosis inducing ligand, as well as perforin and granzyme B mRNA in CD8+ cells using flow cytometry and reverse transcriptase‐polymerase chain reaction. Results: We found that platelet lysis was seen only using purified CD8+ T cells as effector cells; expression of FasL and TNF‐α in CD8+ T cells in ITP group was elevated. Moreover, the mRNA levels of granzyme B and perforin in CD8+ cells of ITP patients were increased. Conclusions: Our findings suggest that CTLs are activated in chronic ITP and might be involved in the pathogenesis of this disorder. Apoptosis and perforin/granzyme‐mediated cytotoxicity constitute an important pathway through which CTLs destruct autologous platelets. CTLs might be a reasonable target for a therapeutic strategy.
The role of corticotropin‐releasing hormone in immune‐mediated cutaneous inflammatory disease
Authors: Kane Marina O' , Murphy Evelyn P. , Kirby Brian
Published: February 2006

Abstract: Corticotropin‐releasing hormone (CRH) coordinates the systemic stress response via hypothalamic‐pituitary‐adrenal (HPA) axis activation with subsequent modulation of the inflammatory response. Stress is known to affect expression of immune‐mediated inflammatory diseases, many of which are associated with HPA axis abnormalities. HPA axis components including CRH and its receptors (CRH‐R) exist in the skin and exhibit differential expression according to cell type, physiological fluctuations and disease states. This confirms a local functioning cutaneous HPA‐like system. Peripheral CRH may exhibit proinflammatory effects. Animal studies confirm that peripheral CRH is required for induction of the inflammatory responsein vivo. CRH and CRH‐R are upregulated in inflammatory arthritis synovium and psoriatic skin. CRH may influence mast cell activation, direct modulation of immune cells, angiogenesis and induction of the novel orphan nuclear receptor NURR1. This transcription factor is part of the steroid/thyroid superfamily of related nuclear receptors that includes receptors for steroids, retinoids and vitamin D; ligands of these receptors are effective in treating psoriasis. The roles of CRH and NURR1 in psoriasis and inflammatory skin diseases, especially those associated with stress, remain to be elucidated. This stress may be psychological or physical. CRH, produced locally or delivered by peripheral nerves, may mediate interactions between a cutaneous HPA axis‐like system and the central HPA axis – the ‘brain‐skin axis’.
Topical treatment with thiazolidinediones, activators of peroxisome proliferator‐activated receptor‐γ, normalizes epidermal homeostasis in a murine hyperproliferative disease model
Authors: Demerjian Marianne , Man Mao‐Qiang , Choi Eung‐Ho , Brown Barbara E. , Crumrine Debra , Chang Sandra , Mauro Theodora , Elias Peter M. , Feingold Kenneth R.
Published: February 2006

Abstract:  In a murine model of epidermal hyperplasia reproducing some of the abnormalities of several common skin disorders, we previously demonstrated the antiproliferative and pro‐differentiating effects of peroxisome proliferator‐activated receptor (PPAR)α, PPARβ/δ, and liver X receptor activators. Unlike other subgroups of PPAR activators, thiazolidinediones (TZDs), a family of PPARγ ligands, did not inhibit keratinocyte proliferation in normal murine skin. Here, we studied the effects of two TZDs, namely ciglitazone (10 mM) and troglitazone (1 mM), in the same murine model where epidermal hyperproliferation was reproduced by repeated barrier abrogation with tape stripping. Topical treatment with ciglitazone and troglitazone resulted in a marked and significant decrease in epidermal thickness. Furthermore, in all TZD‐treated groups, we observed a significant decrease in keratinocyte proliferation using proliferating cell nuclear antigen, 5‐bromo‐2′‐deoxyuridine, and tritiated thymidine incorporation. However, using the terminal deoxynucleotidyl transferase‐mediated dUTP nick end‐labeling assay, we found no difference in apoptosis between different treatments, emphasizing that it is the antiproliferative role of these activators that accounts for the decrease of epidermal thickness. Finally, using immunohistochemical methods, we determined the effects of ciglitazone on keratinocyte differentiation in this hyperproliferative model. We observed an increased expression of involucrin and filaggrin following ciglitazone treatment, suggesting a pro‐differentiating action of TZDs in this model. In summary, topical TZDs significantly reduce epidermal keratinocyte proliferation while promoting differentiation in a murine model of hyperproliferative epidermis. Together, these results suggest that in addition to their metabolic effects currently in use in the treatment of type 2 diabetes, topical TZDs could be considered as potential alternative therapeutic agents in hyperproliferative skin diseases such as psoriasis.
Surfactant protein D in atopic dermatitis and psoriasis
Authors: Hohwy Thomas , Otkjaer Kristian , Madsen Jens , Søerensen Gritt , Nielsen Ole , Vestergaard Christian , Steiniche Torben , Holmskov Uffe , Lomholt Hans
Published: February 2006

Abstract:  The collectin surfactant protein‐D (SP‐D) shows antimicrobial and immuno‐regulatory properties and has recently been detected in the basal layers of normal human skin. This molecule potentially plays an important role in inflammatory skin diseases and therefore SP‐D content and location was examined using immunohistochemistry on skin biopsies from patients with the two major dermatologic diseases, psoriasis and atopic dermatitis. SP‐D was located in the stratum basale of all biopsies with similar intense staining in both diseased and normal skin. Differences were detected in stratum spinosum where involved psoriatic skin showed intense staining through the entire region significantly different from uninvolved and normal skin. Lesional atopic skin showed moderate staining extending through the basal three‐fourths of stratum spinosum. Using real time polymerase chain reaction analysis, no substantial up‐regulation of SP‐D mRNA was detected in lesional psoriatic skin, and a comparison of serum levels of SP‐D between patients with atopic dermatitis or psoriasis and a group of age matched healthy controls did not show significant differences. In conclusion SP‐D was significantly more abundant in the stratum spinosum of lesional psoriatic and atopic skin due to more cells producing the molecule rather than up‐regulation of production in single cells of diseased skin. Further studies are needed to show if SP‐D plays a role in the protection against skin infections or modulation of the inflammatory process in these common skin diseases.
Novel rinse assay for the quantification of oral neutrophils and the monitoring of chronic periodontal disease
Authors: Bender J. S. , Thang H. , Glogauer M.
Published: February 2006

Background and Objectives:  The aim of this study was to develop a single, rapid, noninvasive oral rinse assay to enable the accurate quantification of oral neutrophils. Products released by neutrophils are partly responsible for the destruction observed in periodontitis. Quantification of oral neutrophil levels is important for understanding their role in periodontal diseases. Previous studies have relied on time‐consuming serial rinses and cumbersome counting techniques for the collection and quantification of oral neutrophils.

Material and Methods:  Patients with chronic periodontal disease provided rinse samples before and after phase I periodontal treatment. Cells in the rinse samples were stained with acridine orange, and neutrophil counts were carried out using a fluorescence microscope and a hemocytometer.

Results:  This assay allowed us to detect a significant difference in pretreatment oral neutrophil counts between periodontal disease and healthy control groups (p < 0.001). Patients who responded favorably to phase I therapy demonstrated a 43% reduction in oral neutrophil counts compared with their pretreatment levels (p = 0.019). Patients who did not respond to phase I periodontal treatment showed no significant difference in oral neutrophil levels (p = 0.39).

Conclusion:  Oral neutrophil levels, as determined by a rapid oral rinse, reflect the severity of periodontal disease and treatment response. A single, rapid, oral rinse assay is an effective means of collecting and quantifying oral neutrophil levels and may serve as an excellent research tool for further study of the role of neutrophils in periodontal diseases.
Knowledge of first‐aid measures of avulsion and replantation of teeth: an interview of 221 Kuwaiti schoolchildren
Authors: Andersson Lars , Al‐Asfour Adel , Al‐Jame Qumasha
Published: February 2006

Abstract –  The prognosis of replantation of an avulsed tooth is determined by which first‐aid measures are taken during the first 15 min after avulsion. Knowledge of the correct first‐aid measures is therefore crucial to successful replantation. The aims of this study were (i) to assess the present knowledge level of emergency measures for tooth avulsion in Kuwaiti schoolchildren, and (ii) to design and test an interview form with structured standardized questions. A total of 221 Kuwaiti schoolchildren (aged 7–15 years old) were interviewed by professionals using a standardized method to score several areas of knowledge about tooth avulsion and replantation. Earlier experience of first‐aid information and subjection to dental trauma was registered. The following fields of knowledge were assessed: general body injury treatment principles, tooth avulsion and replantation principles, avulsed permanent/primary teeth, cleaning of avulsed tooth before replantation, extra alveolar time and storage media. The form for interviewing children proved to be sufficiently structured in performing the interviews and data management. The results of the interviews showed that 30.3% of the children had been exposed to dental trauma in the past. Among children 7–9 years of age, 25% had received information on general first aid as compared with 75% in children 10 years and older. Children 10 years and older, in general, had a high knowledge level of general principles of how to manage injuries to the body. Regardless of age group, there were generally a low knowledge level regarding tooth avulsion, replantation, extra‐alveolar time and storage media. We conclude that first‐aid knowledge in Kuwaiti schoolchildren is low on avulsion and replantation of teeth despite a high knowledge level of body injuries. The knowledge level of first‐aid measures on avulsion and replantation of teeth could be increased through intervention programs.
Traumatic intrusion of permanent teeth. Part 1. An epidemiological study of 216 intruded permanent teeth
Authors: Andreasen Jens Ove , Bakland Leif K. , Matras Rannva C. , Andreasen Francis Meriam
Published: February 2006

Abstract –  An epidemiological study of traumatic intrusion of permanent teeth was performed on 216 teeth in 151 patients treated over a 50‐year period at a major trauma center in Denmark (Copenhagen). This analysis showed that intrusion of permanent teeth was of rare injury only affecting 1.9% of traumatic injuries involving permanent teeth. The main etiologic factor appeared to be falling which resulted in axial impacts on maxillary or mandibular teeth. The most common injury patterns were intrusion without additional injuries (33.5%) and intrusion with crown fractures (60.5%). A few cases were combinations of intrusion and either crown/root‐fractures or root fractures (6%). Most often one tooth was intruded (46.3%), followed by two teeth (32.4% ) and three or more teeth (21.3%). The majority of intruded teeth were displaced 2–8 mm. The age group of 6–12 years of age was most frequently involved and boys appeared to experience intrusion injuries more frequently than girls, and at an earlier age. Maxillary central and lateral incisors are the primary victims of intrusions and this seems to be identical to other trauma types and is possibly related to the known exposure to impacts of maxillary incisors. The reliability of clinical findings, such as lack of mobility (81.8%), metallic percussion tone (72.5%), and no pain to percussion (66%) was reasonably high, whereas a radiographic feature such as the obliteration of the periodontal ligament space appeared to be only a partly reliable diagnostic tool (52%).
Traumatic intrusion of permanent teeth. Part 2. A clinical study of the effect of preinjury and injury factors, such as sex, age, stage of root development, tooth location, and extent of injury including number of intruded teeth on 140 intruded permanent teeth
Authors: Andreasen Jens Ove , Bakland Leif K. , Andreasen Frances Meriam
Published: February 2006

Abstract –  A prospective study of 140 intruded permanent teeth was done to evaluate the following healing complications: pulp necrosis (PN), root resorption (surface, inflammatory and replacement resorption) (RR) and defects in marginal periodontal healing (MA). These complications were related to various preinjury and injury factors. Age appeared to be related to all three healing complications in that patients younger than 12 years had the lowest complication rate. Stage of root formation at the time of the injury was very strongly related to PN and MA, with immature root formation (i.e. incomplete root formation or completed root formation with wide open apex) having better prognosis than more mature root development. Lateral incisors showed significantly more defects in MA, a finding possibly explained by the observation that lateral incisors were more often involved in multiple intrusions compared to other teeth and noting that multiple intrusions had a significantly higher frequency of MA. An associated crown fracture with exposed dentin resulted in more frequent PN, a finding possibly related to bacterial invasion through dentinal tubules into an ischemic pulp. The presence of a gingival laceration added to both PN and MA. The extent of intrusion (in mm) showed some relation to both RR with intrusion 1–3 mm having the lowest frequency of RR, whereas PN and MA showed no significant relation to the extent of intrusion. Finally, multiple adjacent intruded teeth were more frequently involved in a significantly greater loss of interproximal marginal bone (MA) than single intrusions. In conclusion, the relationship between healing complications and preinjury and injury factors could generally be explained by better healing possibilities in teeth with immature root formation. A possible explanation for that could be the softer bone surrounding the tooth, whereby trauma to the periodontium might be diminished.
Efficacy and Safety of Tadalafil Across Ethnic Groups and Various Risk Factors in Men with Erectile Dysfunction: Use of a Novel Noninferiority Study Design
Authors: Morgentaler Abraham , Barada James , Niederberger Craig , Donatucci Craig , Garcia Carmen S. , Natanegara Fanni , Ahuja Sanjeev , Wong David G.
Published: February 2006

Aim

This U.S. multicenter open-label study used a noninferiority trial design to assess the efficacy of tadalafil 20 mg to treat erectile dysfunction (ED) in the black American and Hispanic groups compared with a reference group of Caucasians. A secondary objective was to demonstrate the efficacy and safety of tadalafil 20 mg in various populations of men with ED.

Methods

A total of 1,911 patients with ED were enrolled into eight predefined groups: (1–3) Caucasian (Reference group), Black American, or Hispanic patients, ≤65 years of age with no diabetes mellitus or depression; (4) patients with depression, ≤65 years of age, no diabetes; (5) patients with diabetes, ≤65 years of age, no depression; (6) patients >65 years of age, no diabetes or depression; (7) patients who met enrollment criteria but were not included in any other group; and (8) patients with ED due to traumatic spinal cord injury. The study had a 4-week run-in period, followed by a 12-week treatment period with tadalafil taken as needed, up to one dose/day, prior to sexual activity. Change from baseline to endpoint in the Erectile Function (EF) domain of the International Index of Erectile Function (IIEF) was used to determine noninferiority of groups 2 and 3 from group 1. Secondary efficacy measures included other IIEF domains and Sexual Encounter Profile (SEP).

Results

Noninferiority analyses based on the EF domain score showed that tadalafil was as efficacious in the Hispanic and Black American groups as in the Reference group. Patients in each of the eight groups had a significant change from baseline (P < 0.001) in the IIEF EF domain score and positive responses to SEP Questions 1–5. The most common treatment-emergent adverse events reported by patients in all eight groups were headache, nasal congestion, dyspepsia, flushing, and back pain.

Conclusion

Tadalafil 20 mg was as efficacious in the Hispanic and black American groups as in the Caucasian/Reference group. Tadalafil was efficacious and well tolerated in each of the groups studied in this trial.
Vaginal Application of Testosterone: A Study on Pharmacokinetics and the Sexual Response in Healthy Volunteers
Authors: Apperloo Mirjam , Midden Marlies , Van Der Stege Jolande , Wouda Jan , Hoek Annemieke , Weijmar Schultz Willibrord
Published: February 2006

Introduction

Androgen substitution is advocated to improve sexual functioning in women with androgen insufficiency. Nevertheless, the role of androgens in female sexual functioning is not yet unraveled. Even less is known about changes in androgens and the female sexual response.

Aim

The aim of the study is to describe the pharmacokinetics of a single dose of vaginally applied testosterone. In addition, the study aims to gain more insight into the relation between acute changes in testosterone levels and the sexual response in women.

Methods

A randomized, double-blind, crossover study design was used to compare a single vaginal dose of testosterone propionate (2 mg) with placebo. Ten healthy premenopausal women participated. Serum levels of testosterone, free testosterone, and estradiol were measured. The sexual response was measured before application of medication and 4 and 8 hours after application. Erotic video fragments and erotic fantasies were used as stimuli. The genital sexual response was measured using vaginal plethysmography. The subjective sexual response was measured using a visual analog scale.

Results

Vaginal administration of testosterone propionate induced a significant rise in serum testosterone levels and free testosterone levels, but not in serum estradiol levels. Peak levels were reached after 5.5 hours (range 2–12 hours). Mean peak levels of testosterone were 7.71 nmol/L after testosterone propionate and 2.99 nmol/L after placebo (P < 0.005). Mean peak levels of free testosterone were 0.12 nmol/L after testosterone propionate and 0.04 nmol/L after placebo (P < 0.005). Despite marked elevated levels of androgens this study was unable to detect a direct effect on the genital or subjective sexual response.

Conclusions

A single dose of vaginally applied testosterone propionate elevates serum levels of testosterone and free testosterone within 6 hours. Nevertheless, this acute rise in androgens has no effects on the female sexual response.
A unified picture for gamma-ray burst prompt and X-ray afterglow emissions
Authors: Kumar P. , McMahon E. , Barthelmy S. D. , Burrows D. , Gehrels N. , Goad M. , Nousek J. , Tagliaferri G.
Published: February 2006

Data from the Swift satellite have enabled us for the first time to provide a complete picture of the gamma-ray (γ-ray) burst emission mechanism and its relationship with the early afterglow emissions. We show that γ-ray photons for two bursts, 050126 and 050219A, for which we have carried out detailed analysis were produced as a result of the synchrotron self-Compton process in the material ejected in the explosion when it was heated to a mildly relativistic temperature at a distance from the centre of explosion of order the deceleration radius. Both of these bursts exhibit rapidly declining early X-ray afterglow light curves; this emission is from the same source that produced the γ-ray burst. The technique that we exploit to determine this is very general and makes no assumption about any particular model for γ-ray generation except that the basic radiation mechanism is some combination of synchrotron and inverse Compton processes in a relativistic outflow. For GRB 050219A we can rule out the possibility that energy from the explosion is carried outward by magnetic fields, and that the dissipation of this field produced the γ-ray burst.
A RAPID BLADE‐CUTTING METHOD FOR THE EVALUATION OF OSMOTIC DEHYDRATION OF APPLES AND POTATOES
Authors: NUNAK N. , SCHLEINING G.
Published: February 2006

The mass transfer between a sugar solution and sample tissues of apples and potatoes was determined by evaluating the concentration profile of water and the force–distance curves obtained by a blade‐cutting method with a texture analyzer. The shape of the force–distance curves at various processing times was clearly different from that of fresh samples. First, the sample is compressed and the force increases to a “yield point” (YP) when the blade penetrates the surface. After that, the force decreases to a “minimum force point” (MFP) while cutting dehydrated tissue and increases again while cutting nonaffected tissue. The distance at the MFP showed a good correlation to the distance calculated from the concentration‐profile method and can be also used as a parameter to determine the depth of affected sample tissue at various processing time. The blade‐cutting method is much faster and easier to carry out than the concentration‐profile method. Under the used conditions of osmotic dehydration (66% w/w sugar solution, at 20 ± 2C under constant agitation and at atmospheric pressure, sample thickness = 10 mm), the time to dehydrate the samples down to the center was 6 and 3 h for apples and potatoes, respectively.
Action: Forcing Energy to Predict Motion
Authors: Neuenschwander Dwight E. , Taylor Edwin F. , Tuleja Slavomir
Published: February 2006

In this paper we use scalar energy, rather than vector force and momentum, to predict how a particle will move. The result is a quantity called action. Action and its relatives undergird Newton's laws and transcend them, also predicting motion in the quantum world and in the curved spacetime of general relativity. An example exhibits action in action.
Why Are There So Few Female Physicists?
Authors: Robertson Laura Ann
Published: February 2006

It is 1962 and an adolescent female is trying to decide what classes to take; the principal asserts, “a girl has no need for physics.”2 School counselors or administrators may no longer make statements like this; however, the perception that shaped the principal's comment may be part of hidden and subtle discriminatory attitudes still active in today's schools. The point of this paper is to reveal and assess current attitudes toward female participation in physics education and suggest practices to ensure a fair environment for both males and females.
THE IHARA–SELBERG ZETA FUNCTION FOR PGL3 AND HECKE OPERATORS
Authors: DEITMAR ANTON , HOFFMAN J. WILLIAM
Published: February 2006

A weak version of the Ihara formula is proved for zeta functions attached to quotients of the Bruhat–Tits building of PGL3. This formula expresses the zeta function in terms of Hecke-operators. It is the first step towards an arithmetical interpretation of the combinatorially defined zeta function.
EVIDENCE TO SUBCANONICITY OF CODIMENSION TWO SUBVARIETIES OF 𝔾(1,4)
Authors: ARRONDO ENRIQUE , FANIA MARIA LUCIA
Published: February 2006

In this paper, we show that any smooth subvariety of codimension two in 𝔾(1,4) (the Grassmannian of lines of ℙ4) of degree at most 25 is subcanonical. Analogously, we prove that smooth subvarieties of codimension two in 𝔾(1,4) that are not of general type have degree ≤ 32 and we classify all of them. In both classifications, any subvariety in the final list is either a complete intersection or the zero locus of a section of a twist of the rank-two universal bundle on 𝔾(1,4).
MULTIPLICITY ONE PROPERTY AND THE DECOMPOSITION OF b-FUNCTIONS
Authors: SATO FUMIHIRO , SUGIYAMA KAZUNARI
Published: February 2006

Recently, extensive calculations have been made on b-functions of prehomogeneous vector spaces with reducible representations. By examining the results of these calculations, we observe that b-functions of a large number of reducible prehomogeneous vector spaces have decompositions which seem to be correlated to the decomposition of representations. In the present paper, we show that such phenomena can be ascribed to a certain multiplicity one property for group actions on polynomial rings. Furthermore, we give some criteria for the multiplicity one property. Our method can be applied equally to non-regular prehomogeneous vector spaces.
A PUBLIC MESH WATERMARKING ALGORITHM BASED ON ADDITION PROPERTY OF FOURIER TRANSFORM
Authors: LI LI , PAN ZHIGENG , ZHANG DAVID
Published: February 2006

This paper presents a public mesh watermarking algorithm whereby the resultant watermarked image minus the original image is the watermark information. According to the addition property of the Fourier transform, a change of spatial domain will cause a change in the frequency domain. The watermark information is then scaled down and embedded in one part of the x-coordinate of the original mesh. Finally, the x-coordinate of the test mesh is amplified before extraction. Experimental results prove that our algorithm is resistant to a variety of attacks without the need for any preprocessing.
FROM DECISION TO ACTION: INTENTIONALITY, A GUIDE FOR THE SPECIFICATION OF INTELLIGENT AGENT'S BEHAVIOR
Authors: FAVIER PIERRE-ALEXANDRE , DE LOOR PIERRE
Published: February 2006

This article introduces a reflection about behavioral specification for interactive and participative agent-based simulation in virtual reality. Within this context, it is necessary to reach a high level of expressiveness in order to enforce interactions between the designer and the behavioral model during the in-line prototyping. It is required to consider the needs of semantic very early in the design process. The intentional agent model is exposed here as a possible answer. It relies on a mixed imperative and declarative approach which focuses on the link between decision and action. The design of a tool able to simulate virtual environment implying agents based on this model is discussed.
INTEGRATING SHAPE AND TEXTURE FOR HAND VERIFICATION
Authors: KUMAR AJAY , ZHANG DAVID
Published: February 2006

This paper investigates the performance of a bimodal biometric system using fusion of shape and texture. We propose several new hand shape features that can be used to represent the hand shape and improve the performance for hand shape based user authentication. We also demonstrate the usefulness of Discrete Cosine Transform (DCT) coefficients for palmprint authentication. The score level fusion of hand shape and palmprint features using product rule achieves best performance as compared to Max or Sum rule. However the decisions from the Sum, Max, and Product rules can also be combined to further enhance the performance. Thus the fusion of score level decisions, from the multiple strategies, is proposed and investigated. The two hand shapes of an individual are anatomically similar. However, the palmprints from two hands can be combined to further improve performance and is demonstrated in this paper.
NANOSCALE FIELD IONIZATION SENSORS: A REVIEW
Authors: KORATKAR NIKHIL
Published: February 2006

So far, one of the most promising applications of nanoscale science and technology has been in the area of field emission. The electric field amplification effects associated with sharp nanostructure tips can be used to significantly reduce the emission voltages. Another equally promising area that also takes advantage of the field amplification effects is the area of field ionization. The extremely high electrical fields generated near the vicinity of sharp nanostructure tips can be used to ionize chemical or biological species at a fraction of the voltage of a traditional ionizer. In this article we review two of the very first reported papers related to nanoscale field ionization published by our group at the Rensselaer Polytechnic Institute. The first paper describes a carbon nanotube gas ionizer, which shows potential for gas sensing applications. The second paper describes an ultra low-power gas ionizer featuring β-phase Tungsten nanorod electrodes. We end with a review of the major challenges that must be overcome to develop nanoscale ionization sensors.
INDUCED INTERFACES AT NANOSCALES: STRUCTURE AND DYNAMICS
Authors: CHAUDHURI ABHISHEK , CHAUDHURI DEBASISH , SENGUPTA SURAJIT
Published: February 2006

We show how interfaces may be induced in materials using external fields. The structure and the dynamics of these interfaces may then be manipulated externally to achieve desired properties. We discuss three types of such interfaces: an Ising interface in a nonuniform magnetic field, a solid–liquid interface and an interface between a solid and a smectic like phase. In all of these cases we explicitly show how small size, leading to atomic-scale discreteness and stiff constraints produce interesting effects which may have applications in the fabrication of nanostructured materials.
NOVEL METHOD FOR THE SYNTHESIS OF SILOXANE NANOWIRES AND FILAMENTS USING GOLD NANOPARTICLE CATALYSTS
Authors: PRASAD B. L. V. , STOEVA S. , SORENSEN C. M. , KLABUNDE K. J. , ZAIKOVSKII V.
Published: February 2006

A unique polymerization reaction of alkylsilanes to siloxane nanowires, filaments and tubes in presence of gold nanoparticles and water is presented. The gold nanoparticles, which catalyze this reaction also work as templates restricting the shape of the resulting polymers into wires and tubes. High resolution transmission electron microscopy images clearly reveal the presence of gold nanoparticle at the tip of each wire supporting the template hypothesis. Elemental analyses by different methods confirm the stoichiometry to be C 18 H 37 SiO 1.5, when the alkylsilane used was C 18 H 37 SiH 3, thus proving that the alkyl group remains intact during the polymerization reaction.
SOLID STATE AMORPHIZATION IN MECHANICALLY ALLOYED Al–Ti–Si NANOCOMPOSITES
Authors: MANNA I. , NANDI P. , BANDYOPADHYAY B. , NAMBISSAN P. M. G. , GHOSHRAY K. , GHOSHRAY A.
Published: February 2006

The microstructural evolution at different stages of milling of a ternary powder blend of Al 50 Ti 40 Si 10 composition was monitored by X-ray diffraction, high-resolution transmission electron microscopy, positron annihilation spectroscopy and 27 Al nuclear magnetic resonance. Ball-milling leads to alloying, nanocrystallization and partial solid state amorphization, either followed or accompanied by strain-induced nucleation of nanocrystalline intermetallic phases from an amorphous solid solution.
Signaling Pathways in Skeletal Muscle Remodeling
Authors: Bassel-Duby Rhonda , Olson Eric N.
Published: February 2006

Skeletal muscle is comprised of heterogeneous muscle fibers that differ in their physiological and metabolic parameters. It is this diversity that enables different muscle groups to provide a variety of functional properties. In response to environmental demands, skeletal muscle remodels by activating signaling pathways to reprogram gene expression to sustain muscle performance. Studies have been performed using exercise, electrical stimulation, transgenic animal models, disease states, and microgravity to show genetic alterations and transitions of muscle fibers in response to functional demands. Various components of calcium-dependent signaling pathways and multiple transcription factors, coactivators and corepressors have been shown to be involved in skeletal muscle remodeling. Understanding the mechanisms involved in modulating skeletal muscle phenotypes can potentiate the development of new therapeutic measures to ameliorate muscular diseases.
Genome Packaging by Spherical Plant RNA Viruses
Authors: Rao A.L.N.
Published: February 2006

Abstract  The majority of positive-strand RNA viruses of plants replicate and selectively encapsidate their progeny genomes into stable virions in cytoplasmic compartments of the cell where the opportunity to copackage cellular RNA also exists. Remarkably, highly purified infectious virions contain almost exclusively viral RNA, suggesting that mechanisms exist to regulate preferential packaging of viral genomes. The general principle that governs RNA packaging is an interaction between the structural CP and a specific RNA signal. Mechanisms that enhance selective packaging of viral genomes and formation of infectious virions may involve factors other than CP and nucleic acid sequences. The possible involvement of replicase proteins is an example. Our knowledge concerning genome packaging among spherical plant RNA viruses is still maturing. The main focus of this review is to discuss factors that have limited progress and to evaluate recent technical breakthroughs likely to help unravel the mechanism of RNA packaging among viruses of agronomic importance. A key breakthrough is the development of in vivo systems and comparisons with results obtained in vitro.
Nonsystemic Bunt Fungi—Tilletia indica and T. horrida: A Review of History, Systematics, and Biology
Authors: Carris Lori M. , Castlebury Lisa A. , Goates Blair J.
Published: February 2006

Abstract  The genus Tilletia is a group of smut fungi that infects grasses either systemically or locally. Basic differences exist between the systemically infecting species, such as the common and dwarf bunt fungi, and locally infecting species. Tilletia indica, which causes Karnal bunt of wheat, and Tilletia horrida, which causes rice kernel smut, are two examples of locally infecting species on economically important crops. However, even species on noncultivated hosts can become important when occurring as contaminants in export grain and seed shipments. In this review, we focus on T. indica and the morphologically similar but distantly related T. horrida, considering history, systematics, and biology. In addition, the controversial generic placement and evolutionary relationships of these two species are discussed in light of recent molecular studies.
First-year medical students prefer multiple learning styles
Authors: Lujan Heidi L. , DiCarlo Stephen E.
Published: February 2006

Students have preferences for the ways in which they receive information. The visual, auditory, reading/writing, kinesthetic (VARK) questionnaire identifies student's preferences for particular modes of information presentation. We administered the VARK questionnaire to our first-year medical students, and 166 of 250 students (66%) returned the completed questionnaire. Only 36.1% of the students preferred a single mode of information presentation. Among these students, 5.4% preferred visual (learning from graphs, charts, and flow diagrams), 4.8% preferred auditory (learning from speech), 7.8% preferred printed words (learning from reading and writing), and 18.1% preferred using all their senses (kinesthetics: learning from touch, hearing, smell, taste, and sight). In contrast, most students (63.8%) preferred multiple modes [2 modes (24.5%), 3 modes (32.1%), or 4 modes (43.4%)] of information presentation. Knowing the students preferred modes can 1) help provide instruction tailored to the student's individual preference, 2) overcome the predisposition to treat all students in a similar way, and 3) motivate teachers to move from their preferred mode(s) to using others.
Teaching the effects of gravity and intravascular and alveolar pressures on the distribution of pulmonary blood flow using a classic paper by West et al.
Authors: Levitzky Michael G.
Published: February 2006

“Distribution of blood flow in isolated lung; relation to vascular and alveolar pressures” by J. B. West, C. T. Dollery, and A. Naimark ( J Appl Physiol 19: 713–724, 1964) is a classic paper, although it has not yet been included in the Essays on the American Physiological Society Classic Papers Project ( http://www.the-aps.org/publications/classics/ ). This is the paper that originally described the “zones of the lung.” The final figure in the paper, which synthesizes the results and discussion, is now seen in most textbooks of physiology or respiratory physiology. The paper is also a model of clear, concise writing. The paper and its final figure can be used to teach or review a number of physiological concepts. These include the effects of gravity on pulmonary blood flow and pulmonary vascular resistance; recruitment and distention of pulmonary vessels; the importance of the transmural pressure on the diameter of collapsible distensible vessels; the Starling resistor; the interplay of the pulmonary artery, pulmonary vein, and alveolar pressures; and the vascular waterfall. In addition, the figure can be used to generate discovery learning and discussion of several physiological or pathophysiological effects on pulmonary vascular resistance and the distribution of pulmonary blood flow.
Evaluation of nonlinear regression approaches to estimation of insulin sensitivity by the minimal model with reference to Bayesian hierarchical analysis
Authors: Godsland Ian F. , Agbaje Olorunsola F. , Hovorka Roman
Published: February 2006

Minimal model analysis of intravenous glucose tolerance test (IVGTT) glucose and insulin concentrations offers a validated approach to measuring insulin sensitivity, but model identification is not always successful. Improvements may be achieved by using alternative settings in the modeling process, although results may differ according to setting, and care must be exercised in combining results. IVGTT data (12 samples, regular test) from 533 men without diabetes was modeled by the traditional nonlinear regression (NLR) approach, using five different permutations of settings. Results were evaluated with reference to the more robust Bayesian hierarchical (BH) approach to model identification and to the proportion of variance they explained in known correlates of insulin sensitivity (age, BMI, blood pressure, fasting glucose and insulin, serum triglyceride, HDL cholesterol, and uric acid concentration). BH analysis was successful in all cases. With NLR analysis, between 17 and 35 IVGTTs were associated with parameter coefficients of variation (PCVs) for minimal model parameters SI(insulin sensitivity) and SG(glucose effectiveness) of >100%. Systematic use of each different approach in combination reduced this number to five. Mean (interquartile range) SINLRwas then 3.14 (2.29–4.63) min−1·mU−1·l × 10−4and 2.56 (1.74–3.83) min−1·mU−1·l × 10−4for SIBH(correlation 0.86, P < 0.0001). SINLRexplained, on average, 10.6% of the variance in known correlates of insulin sensitivity, whereas SIBHexplained 8.5%. In a large body of data, which BH analysis demonstrated could be fully identified, use of alternative modeling settings in NLR analysis could substantially reduce the number of analyses with PCVs >100%. SINLRcompared favorably with SIBHin the proportion of variance explained in known correlates of insulin sensitivity.
Anti-inflammatory and antinecrotic effects of the volatile anesthetic sevoflurane in kidney proximal tubule cells
Authors: Lee H. Thomas , Kim Mihwa , Jan Michael , Emala Charles W.
Published: February 2006

Renal ischemia-reperfusion (IR) injury is a major clinical problem without effective therapy. We recently reported that volatile anesthetics protect against renal IR injury, in part, via their anti-inflammatory properties. In this study, we demonstrate the anti-inflammatory and antinecrotic effects of sevoflurane in cultured kidney proximal tubule cells and probed the mechanisms of sevoflurane-induced renal cellular protection. To mimic inflammation, human kidney proximal tubule (HK-2) cells were treated with tumor necrosis factor-α (TNF-α; 25 ng/ml) in the presence or absence of sevoflurane. In addition, we studied the effects of sevoflurane pretreatment on hydrogen peroxide (H2O2)-induced necrotic cell death in HK-2 or porcine proximal tubule (LLC-PK1) cells. We demonstrate that sevoflurane suppressed proinflammatory effects of TNF-α evidenced by attenuated upregulation of proinflammatory cytokine mRNA (TNF-α, MCP-1) and ICAM-1 protein and reduced nuclear translocation of the proinflammatory transcription factors NF-κB and AP-1. Sevoflurane reduced necrotic cell death induced with H2O2in HK-2 cells as well as in LLC-PK1cells. Sevoflurane treatment resulted in phosphorylation of prosurvival kinases, ERK and Akt, and increased de novo HSP-70 protein synthesis without affecting the synthesis of HSP-27 or HSP-32. We conclude that sevoflurane has direct anti-inflammatory and antinecrotic effects in vitro in a renal cell type particularly sensitive to injury following IR injury. These mechanisms may, in part, account for volatile anesthetics' protective effects against renal IR injury.
Regulation of the Na-K-ATPase β1-subunit promoter by multiple prostaglandin-responsive elements
Authors: Matlhagela Keikantse , Taub Mary
Published: February 2006

Renal prostaglandins modulate the activity of a number of the transport systems in the kidney, including the Na-K-ATPase. Not only do prostaglandins have acute affects on renal Na-K-ATPase, but in addition prostaglandins have chronic affects, which include regulation at the transcriptional level. Previously, we have presented evidence that one such prostaglandin, PGE1, stimulates the transcription of the human Na-K-ATPase β1-subunit gene in Madin-Darby canine kidney cells via cAMP- and Ca2+-mediated pathways (Taub M, Borsick M, Geisel J, Matlhagela K, Rajkhowa T, and Allen C. Exp Cell Res 299: 1–14, 2004; Matlhagela K, Borsick M, Rajkhowa T, and Taub M. J Biol Chem 280: 334–346, 2005). Evidence was presented indicating that PGE1stimulation was mediated through the binding of cAMP-regulatory element binding protein (CREB) to a prostaglandin-responsive element (PGRE) as well as Sp1 binding to an adjacent Sp1 site. In this report, we present evidence from EMSAs and DNA affinity precipitation studies that another PGRE present in the Na-K-ATPase β1-subunit promoter similarly binds CREB and Sp1. The evidence that indicates a requirement for CREB as well as Sp1 for gene activation through both PGREs (PGRE1 and PGRE3) includes studies with a dominant negative CREB (KCREB), Drosophila SL2 cells, and PGRE mutants. The results of these studies are indicative of a synergism between Sp1 and CREB in mediating regulation by PGRE3; while regulation occurring through PGRE1 also involves Sp1 and CREB, the mechanism appears to be distinct.
Transport of estrone sulfate by the novel organic anion transporter Oat6 (Slc22a20)
Authors: Schnabolk Gloriane W. , Youngblood Geri L. , Sweet Douglas H.
Published: February 2006

Recently, a novel Slc22 gene family member expressed in murine olfactory mucosa was identified and based on sequence homology proposed to be an organic anion transporter [Oat6 ( Slc22a20); J. C. Monte, M. A. Nagle, S. A. Eraly, and S. K. Nigam. Biochem Biophys Res Commun 323: 429–436, 2004]. However, no functional data for Oat6 was reported. In the present study, we demonstrate that murine Oat6 mediates the inhibitable transport of estrone sulfate using both Xenopus oocyte expression assay and Chinese hamster ovary (CHO) cells stably transfected with mOat6 (CHO-mOat6). Uptake was virtually eliminated by probenecid and the anionic herbicide 2,4-dichlorophenoxyacetate. The organic anions ochratoxin A, salicylate, penicillin G, p-aminohippurate, and urate inhibited mOat6-mediated accumulation to varying degrees. Transport of estrone sulfate by mOat6 was demonstrated to be saturable, and Kmestimates of 109.8 ± 22.6 μM in oocytes and 44.8 ± 7.3 μM in CHO-mOat6 cells were obtained. Inhibitory constants for 2,4-dichlorophenoxyacetate (15.7 ± 2.0 μM), salicylate (49.0 ± 4.4 μM), probenecid (8.3 ± 2.5 μM), and penicillin G (1,450 ± 480 μM) were also determined. Accumulation of estrone sulfate mediated by mOat6 was significantly trans-stimulated by glutarate, indicating that mOat6 functions as an organic anion/dicarboxylate exchanger. These data demonstrate for the first time that the novel murine gene Oat6 ( Slc22a20) encodes a functional organic anion transporter and mOat6 is indeed the newest member of the OAT gene family.
Parietal Area 5 Activity Does Not Reflect the Differential Time-Course of Motor Output Kinetics During Arm-Reaching and Isometric-Force Tasks
Authors: Hamel-Pâquet Catherine , Sergio Lauren E. , Kalaska John F.
Published: February 2006

Many single-neuron recording studies have examined the degree to which the activity of primary motor cortex (M1) neurons is related to the kinematics and kinetics of various motor tasks. This has not been explored as extensively for arm movement-related neurons in posterior parietal cortex area 5. We recorded the activity of 78 proximal arm–related neurons in area 5 of two monkeys while they used their whole arm to make reaching movements toward eight targets on a horizontal plane against an inertial load or to generate isometric forces at the hand in the same eight horizontal directions. The overall range of measured output forces was similar in the two tasks. The forces increased monotonically in the desired direction in the isometric task. In the movement task, in contrast, they showed a rapid initial increase in the direction of movement, followed by a transient reversal of forces as the hand approached the target. Many task-related area 5 neurons were tuned for the direction of motor output in the tasks, but most area 5 neurons were more strongly active or exclusively active in the movement task than in the isometric task. Furthermore, their activity at either the single cell or population level did not reflect the transient reversal of output forces during movement. In contrast, M1 neuronal activity was typically strong in both tasks and showed task-related changes that reflected the differences in the time course and directionality of force outputs between both tasks, including the transient reversal of forces in the movement task. These results show that area 5 neurons are less strongly related to the time-course of task kinetics than M1 during isometric and arm-movement tasks.