bluuebunny/crossref_metadata_2025 huggingface dataset:
Response of taxonomic groups in streams to gradients in resource and habitat characteristics
Authors: Johnson Richard K. , Hering Daniel
Published: December 2008

Compared to other ecosystem types, a wide variety of biomonitoring methods are available for rivers. Few studies have, however, compared the response of bioindicators (i.e. different river inhabiting taxonomic groups) to different types of environmental stress.

We regressed diversity, taxonomic distinctness and assemblage composition of fish, invertebrates, macrophytes and benthic diatoms to multivariate gradients in nutrient enrichment and habitat degradation using data from 66 lowland and 77 mountain streams.

In lowland streams, the composition of benthic diatom assemblages, measured by Detrended Correspondence Analysis, showed the strongest response to elevated nutrient concentrations (R2 = 0·830), followed by macrophytes (0·711), fish (0·443) and invertebrates (0·391). Macrophyte richness was slightly better correlated with the habitat gradient (0·253) than diatom richness (0·235) and both were better predictors than either fish (0·147) or invertebrate (0·140) assemblage composition.

For mountain streams, invertebrate assemblage composition was the best predictor of changes in nutrient concentrations (R2 = 0·749), followed by macrophyte (0·396) and benthic diatom (0·325) assemblages and fish diversity (0·099). Invertebrate assemblage composition was also slightly better correlated with the habitat gradient (0·391) compared to macrophyte richness (0·323) and both were better than either benthic diatom assemblage composition (0·206) or fish abundance (0·161).

Macrophyte and benthic diatom assemblages in lowland streams and fish and invertebrate assemblages in mountain streams were correlated with the other taxonomic groups, implying that these taxonomic groups may be used as surrogates for indicating wholesale change in diversity.

Synthesis and applications. Our findings show that response trajectories differ between taxonomic groups and stressor, and even with stream type. For this reason, streams and other ecosystem type's response signatures and first and second principle relations should be considered in the selection of robust, complementary and cost‐effective measures for biomonitoring. For instance, our findings of asymmetric response to stress show how different taxonomic groups can be used to strengthen inference of change.
Annotation: New research into general psychiatric services for adults with intellectual disability and mental illness
Authors: Chaplin R.
Published: December 2008

Background  There are a variety of models for the mental health care of adults with comorbid intellectual disability (ID) and mental illness. There has been a long‐running debate as to whether this should be provided by general psychiatric or specialised ID services. A previous review concluded that there was no clear evidence to support either model with research being often of a poor quality, lacking replication, and outcome measures were often inappropriate or varied between studies. This review aims assess differences in outcome for patients with ID and mental disorders treated in general or specialised ID mental health services.

Method  A literature review was conducted using electronic databases and websites of ID and mental health organisations to locate all references where people with ID receive mental health care in general psychiatric services from 2003. No meta‐analysis was attempted because of the divergent nature of the studies.

Results  People with ID (especially severe ID) have reduced access to general psychiatric services. General psychiatric inpatient care is unpopular especially with carers but can be improved by providing specially trained staff and in‐reach from community ID teams. Opportunities may exist to enhance the care of people with borderline intellectual functioning within general psychiatric services.

Conclusions  Although no new randomised controlled trials have been published, the weight of research is accumulating to suggest that provision of general psychiatric services without extra help is not sufficient to meet the needs of people with ID.
Extraction and labeling methods for microarrays using small amounts of plant tissue
Authors: Stimpson Alexander J. , Pereira Rhea S. , Kiss John Z. , Correll Melanie J.
Published: December 2008

Procedures were developed to maximize the yield of high‐quality RNA from small amounts of plant biomass for microarrays. Two disruption techniques (bead milling and pestle and mortar) were compared for the yield and the quality of RNA extracted from 1‐week‐old Arabidopsis thaliana seedlings (approximately 0.5–30 mg total biomass). The pestle and mortar method of extraction showed enhanced RNA quality at the smaller biomass samples compared with the bead milling technique, although the quality in the bead milling could be improved with additional cooling steps. The RNA extracted from the pestle and mortar technique was further tested to determine if the small quantity of RNA (500 ng–7 μg) was appropriate for microarray analyses. A new method of low‐quantity RNA labeling for microarrays (NuGEN Technologies, Inc.) was used on five 7‐day‐old seedlings (approximately 2.5 mg fresh weight total) of Arabidopsis that were grown in the dark and exposed to 1 h of red light or continued dark. Microarray analyses were performed on a small plant sample (five seedlings; approximately 2.5 mg) using these methods and compared with extractions performed with larger biomass samples (approximately 500 roots). Many well‐known light‐regulated genes between the small plant samples and the larger biomass samples overlapped in expression changes, and the relative expression levels of selected genes were confirmed with quantitative real‐time polymerase chain reaction, suggesting that these methods can be used for plant experiments where the biomass is extremely limited (i.e. spaceflight studies).
BLADDER NECK STENOSIS IN CHILDREN—IS IT IMPORTANT?1
Authors: Grieve John
Published: December 2008

Thirty‐eight young people aged 4 to 18 years had chronic urinary infection or enuresis or both. All had bladder neck stenosis and the main infecting organism was E. coli. Thirty‐seven had a Y‐V plasty done and all but four of the enuretics showed considerable improvement. In six children there was complete cure. The relative incidence of bladder neck and distal urethral stenosis is not agreed, but this paper gives evidence that treatment of bladder neck stenosis is likely to benefit the patient.
Effects of multiple study–test repetition on the neural correlates of recognition memory: ERPs dissociate remembering and knowing
Authors: De Chastelaine Marianne , Friedman David , Cycowicz Yael M. , Horton Cort
Published: December 2008

Event‐related potential (ERP) frontal (300–500 ms) and parietal (500–700 ms) episodic memory (EM) effects are thought to reflect, respectively, familiarity and recollection. However, as most ERP studies use preexperimentally familiar items, an alternative idea is that the frontal EM effect reflects conceptual priming. Repetition of unnameable symbols was used to assess modulations of the putative ERP indices of familiarity and recollection. The same symbols were viewed in each of 4 study/test blocks. Increases in familiarity and conceptual processing of symbols did not modulate the frontal EM effect, suggesting that it reflects neither familiarity nor conceptual priming. The magnitude of the parietal EM effect increased and its onset latency decreased across tests for items given remember (R) but not know (K) judgments. R and K old–new topographies differed. These findings support dual‐process proposals that familiarity‐ and recollection‐based processes are distinct.
Parallel processing of affective visual stimuli
Authors: Peyk Peter , Schupp Harald T. , Keil Andreas , Elbert Thomas , Junghöfer Markus
Published: December 2008

Event‐related potential (ERP) studies of affective picture processing have demonstrated an early posterior negativity (EPN) for emotionally arousing pictures that are embedded in a rapid visual stream. The present study examined the selective processing of emotional pictures while systematically varying picture presentation rates between 1 and 16 Hz. Previous results with presentation rates up to 5 Hz were replicated in that emotional compared to neutral pictures were associated with a greater EPN. Discrimination among emotional and neutral contents was maintained up to 12 Hz. To explore the notion of parallel processing, convolution analysis was used: EPNs generated by linear superposition of slow rate ERPs explained 70%–93% of the variance of measured EPNs, giving evidence for an impressive capacity of parallel affective discrimination in rapid serial picture presentation.
Visual P3 amplitude and self‐reported psychopathic personality traits: Frontal reduction is associated with self‐centered impulsivity
Authors: Carlson Scott R. , Thái Stephanie , McLarnon Megan E.
Published: December 2008

Past studies have examined P3 amplitude as an index of cognitive function related to psychopathy with mixed results. Psychopathy is a heterogeneous set of dissociable traits, and no previous study has examined relationships between P3 and specific traits. A Two Process Theory (TPT) of psychopathy has recently been advanced predicting that P3 reductions are related to only one dimension. We evaluated the relationship between P3 and the two factors of the Psychopathic Personality Inventory (PPI) in 96 undergraduates who performed a visual task. One factor of the PPI, Self‐Centered Impulsivity, is related to the dimension of the TPT predicted to underlie P3 reduction. Frontal amplitude reduction was uniquely and inversely related to this trait. The other PPI factor, Fearless Dominance, was associated with faster reaction times. Future work on psychopathic personality and P3 should evaluate whether relationships are unique to one personality dimension.
Differentiation of myoclonic seizures in epileptic syndromes: A video‐polygraphic study of 26 patients
Authors: Hirano Yoshiko , Oguni Hirokazu , Funatsuka Makoto , Imai Kaoru , Osawa Makiko
Published: December 2008

Objective:  We conducted a video‐polygraphic study of myoclonic seizures (MS) in different epileptic syndromes to clarify semiologic and electroencephalography (EEG) differences among them.

Subjects and methods:  The subjects were 26 children with MS, including benign myoclonic epilepsy in infants (BME) in 10, severe myoclonic epilepsy in infants (SME) in 6, idiopathic epilepsy with myoclonic‐astatic seizures (IEMAS) in 4, and juvenile myoclonic epilepsy (JME) in 6. We reviewed the video‐polygraphs of MS, including the predominant area of muscle involvement (neck, trunk, and proximal or distal upper extremities), postural changes including astatic falling, and mode of appearance. We also analyzed the frequency of a corresponding generalized spike‐and‐wave complex (GSW) and the duration of myoclonic electromyography (EMG) activity.

Results:  A total of 550 MS were documented in the 26 cases. MS manifested with proximal predominance/forward flexion/single occurrence in BME, proximal predominance/forward astatic flexion/single occurrence in IEMAS, proximal predominance/extension/succession in SME, and distal predominance/extension/succession in JME. The median frequency of GSW was 1.5, 1.3, 3.2, and 3.1 Hz, respectively, and the median duration of the myoclonic EMG activity was 387, 587, 81, and 65 ms, respectively.

Conclusion:  MS in the four different epileptic syndromes show significant semiologic and EEG differences, as well as similarities. Although our study has the limitations of the small number of patients and retrospective methodology, these results should be considered in the classification and differential diagnosis of myoclonic epileptic syndromes.
High‐frequency oscillations: What is normal and what is not?
Authors: Engel Jr Jerome , Bragin Anatol , Staba Richard , Mody Istvan
Published: December 2008

High‐frequency oscillations (HFOs) in the 80–200 Hz range can be recorded from normal hippocampus and parahippocampal structures of humans and animals. They are believed to reflect inhibitory field potentials, which facilitate information transfer by synchronizing neuronal activity over long distances. HFOs in the range of 250–600 Hz (fast ripples, FRs) are pathologic and are readily recorded from hippocampus and parahippocampal structures of patients with mesial temporal lobe epilepsy, as well as rodent models of this disorder. These oscillations, and similar HFOs recorded from neocortex of patients, appear to identify brain tissue capable of spontaneous ictogenesis and are believed to reflect the neuronal substrates of epileptogenesis and epileptogenicity. The distinction between normal and pathologic HFOs (pHFOs), however, cannot be made on the basis of frequency alone, as oscillations in the FR frequency range can be recorded from some areas of normal neocortex, whereas oscillations in the ripple frequency range are present in epileptic dentate gyrus where normal ripples never occur and, therefore, appear to be pathologic. The suggestion that FRs may be harmonics of normal ripples is unlikely, because of their spatially distinct generators, and evidence that FRs reflect synchronized firing of abnormally bursting neurons rather than inhibitory field potentials. These synchronous population spikes, however, can fire at ripple frequencies, and their harmonics appear to give rise to FRs. Investigations into the fundamental neuronal processes responsible for pHFOs could provide insights into basic mechanisms of epilepsy. The potential for pHFOs to act as biomarkers for epileptogenesis and epileptogenicity is also discussed.
Solving the “Lachmann Problem”: Orientation, Individualism, and the Causal Explanation of Socioeconomic Order
Authors: Lewis Paul
Published: December 2008

Abstract

This article examines the question of whether social institutions should be treated as possessing the sui generis causal power to influence people's actions. It does so by means of a case study of the work of the Austrian economist Ludwig Lachmann. Lachmann's account of how social institutions facilitate intentional human agency in the face of uncertainty contains significant ambiguities and tensions, stemming from his reluctance to acknowledge the causal efficacy of social institutions. The conceptual resources required to overcome these problems are to be found in realist social philosophy and social theory. The proposed resolution comes at a price, however, for it calls into question Lachmann's self‐avowed commitment to methodological individualism.
Systemic Mycobacterium kansasii infection mimicking peripheral T‐cell lymphoma
Authors: CHEN YA‐PING , YEN YU‐SHAN , CHEN TSAI‐YUN , YEN CHIA‐LIANG , SHIEH CHI‐CHANG , CHANG KUNG‐CHAO
Published: December 2008

Nontuberculous mycobacteria are opportunistic pathogens which predominantly infect the immunocompromised host. The clinical and pathologic diagnosis of mycobacterial infection is generally not difficult. However, it may mimic malignancy on account of the clinical manifestations or the morphology of atypical lymphocytes with epithelioid histiocytes. The latter can be found in some types of lymphomas, especially T‐cell lymphoma. This report describes two immunocompetent patients with systemic Mycobacterium kansasii infection presenting with fever, systemic lymphadenopathy, and osteolytic bone lesions. The microscopic features of these two cases were similar and were characterized by effacement of the nodal architecture by lymphocytic infiltrates and small aggregates of epithelioid histiocytes throughout. These lymphocytes showed mild atypia and expressed predominantly CD3. Bone marrow was also involved in the same process in one case and T‐cell lymphoma with lymphoepithelioid features was the initial impression. However, further studies reported germline arrangements of T‐cell receptor genes, presence of acid‐fast bacilli, and recovery of M. kansasii in culture. At follow‐up, the lymphadenopathy was seen to have disappeared during antimycobacterial treatment. This report describes two infectious cases with small aggregates of epithelioid histiocytes and atypical lymphocytes mimicking peripheral T‐cell lymphoma; and such cases may become more common as the number of immunosuppressed hosts is increasing worldwide. We have reviewed the literature and summarized useful morphologic criteria for differentiation.
Role of the Plasmodium Export Element in Trafficking Parasite Proteins to the Infected Erythrocyte
Authors: Boddey Justin A , Moritz Robert L , Simpson Richard J , Cowman Alan F
Published: December 2008

The intracellular survival of Plasmodium falciparum within human erythrocytes is dependent on export of parasite proteins that remodel the host cell. Most exported proteins require a conserved motif (RxLxE/Q/D), termed the Plasmodium export element (PEXEL) or vacuolar targeting sequence (VTS), for targeting beyond the parasitophorous vacuole membrane and into the host cell; however, the precise role of this motif in export is poorly defined. We used transgenic P. falciparum expressing chimeric proteins to investigate the function of the PEXEL motif for export. The PEXEL constitutes a bifunctional export motif comprising a protease recognition sequence that is cleaved, in the endoplasmic reticulum, from proteins destined for export, in a PEXEL arginine‐ and leucine‐dependent manner. Following processing, the remaining conserved PEXEL residue is required to direct the mature protein to the host cell. Furthermore, we demonstrate that N acetylation of proteins following N‐terminal processing is a PEXEL‐independent process that is insufficient for correct export to the host cell. This work defines the role of each residue in the PEXEL for export into the P. falciparum‐infected erythrocyte.
Anabolic‐androgenic steroid treatment induces behavioral disinhibition and downregulation of serotonin receptor messenger RNA in the prefrontal cortex and amygdala of male mice
Authors: Ambar G. , Chiavegatto S.
Published: December 2008

Nandrolone is an anabolic‐androgenic steroid (AAS) that is highly abused by individuals seeking enhanced physical strength or body appearance. Supraphysiological doses of this synthetic testosterone derivative have been associated with many physical and psychiatric adverse effects, particularly episodes of impulsiveness and overt aggressive behavior. As the neural mechanisms underlying AAS‐induced behavioral disinhibition are unknown, we investigated the status of serotonergic system‐related transcripts in several brain areas of mice receiving prolonged nandrolone administration. Male C57BL/6J mice received 15 mg/kg of nandrolone decanoate subcutaneously once daily for 28 days, and different sets of animals were used to investigate motor‐related and emotion‐related behaviors or 5‐HT‐related messenger RNA (mRNA) levels by real‐time quantitative polymerase chain reaction. AAS‐injected mice had increased body weight, were more active and displayed anxious‐like behaviors in novel environments. They exhibited reduced immobility in the forced swim test, a higher probability of being aggressive and more readily attacked opponents. AAS treatment substantially reduced mRNA levels of most investigated postsynaptic 5‐HT receptors in the amygdala and prefrontal cortex. Interestingly, the 5‐HT1B mRNA level was further reduced in the hippocampus and hypothalamus. There was no alteration of 5‐HT system transcript levels in the midbrain. In conclusion, high doses of AAS nandrolone in male mice recapitulate the behavioral disinhibition observed in abusers. Furthermore, these high doses downregulate 5‐HT receptor mRNA levels in the amygdala and prefrontal cortex. Our combined findings suggest these areas as critical sites for AAS‐induced effects and a possible role for the 5‐HT1B receptor in the observed behavioral disinhibition.
Extrasinus Zygomatic Implants: Three Year Experience from a New Surgical Approach for Patients with Pronounced Buccal Concavities in the Edentulous Maxilla
Authors: Aparicio Carlos , Ouazzani Wafaa , Aparicio Arnau , Fortes Vanessa , Muela Rosa , Pascual Andrés , Codesal Maria , Barluenga Natalia , Manresa Carolina , Franch Monica
Published: December 2008

Background: The surgical protocol for zygomatic fixtures prescribes an intrasinus approach ideally maintaining the sinus membrane intact and the implant body inside the sinus while gaining access to the zygomatic bone. In the presence of a pronounced buccal concavity, the implant head has to be placed far from the alveolar crest in a palatal direction, which results in a bulky bridge construction.

Purpose: The aim of this study was to report on the preliminary experiences with zygomatic implants placed with an extrasinus approach in order to have the implant head emerging at or near the top of the alveolar crest.

Materials and Methods: Twenty consecutive patients with pronounced buccal concavities in the edentulous posterior maxilla were treated with 104 regular and 36 zygomatic implants as support of fixed dental bridges. Sixteen patients were treated bilaterally and four patients were treated unilaterally. The zygomatic implants were inserted by using an extrasinus surgical approach with the implant body passing from the alveolar crest through the buccal concavity into the zygomatic bone. This enabled placement of the implant head at or close to the alveolar crest. The patients were followed from 36 to 48 months after occlusal loading with a mean follow‐up of 41 months. The relation of the zygomatic implants to the crest was measured and compared with a control group of 20 patients treated with conventional placement of zygomatic implants.

Results: No implants were lost during the study period. No pain, discomfort, or complications related to the extrasinus path of the zygomatic implants were recorded after the initial healing period and up to the 36th‐month checkup. The zygomatic implants emerged, on average, 3.8 mm (SD 2.6) palatal to the top of the crest compared with 11.2 mm (SD 5.3) to the conventional technique.

Conclusion: The present 3‐year clinical study shows that an extrasinus approach can be utilized when placing zygomatic implants in patients with pronounced buccal concavities in the posterior maxilla. Moreover, the technique results in an emergence of the zygomatic fixture close to the top of the crest, which is beneficial from a cleaning and patient‐comfort point of view.
Bone Formation Following Implantation of Titanium Sponge Rods into Humeral Osteotomies in Dogs: A Histological and Histometrical Study
Authors: Faria Paulo Esteves Pinto , Carvalho Alexandre Leite , Felipucci Daniela Nair Borges , Wen Cui'e , Sennerby Lars , Salata Luiz Antonio
Published: December 2008

Background: Titanium (Ti) is widely proven to enhance bone contact and growth on its surface. It is expected that bone defects could benefit from Ti to promote healing and to increase strength of the implanted area.

Purpose: The present study aimed at comparing the potential of porous Ti sponge rods with synthetic hydroxyapatite (HA) for the healing of bone defects in a canine model.

Material and Methods: Six mongrel dogs were submitted to three trephined osteotomies of 6.0 × 4.0 mm in one humerus and after 2 months another three osteotomies were performed in the contralateral humerus. A total of 36 defects were randomly filled either with Ti foam, particulate HA, or coagulum (control). The six animals were killed 4 months after the first surgery for histological and histometrical analysis.

Results: The Ti‐foam surface was frequently found in intimate contact with new bone especially at the defect walls. Control sites showed higher amounts of newly formed bone at 2 months – Ti (p = 0.000) and HA (p = 0.009) – and 4 months when compared with Ti (p = 0.001). Differently from HA, the Ti foam was densely distributed across the defect area which rendered less space for bone growth in the latter's sites. The use of Ti foams or HA resulted in similar amounts of bone formation in both time intervals. Nevertheless, the presence of a Ti‐foam rod preserved defect's marginal bone height as compared with control groups. Also, the Ti‐foam group showed a more mature bone pattern at 4 months than HA sites.

Conclusion: The Ti foam exhibited good biocompatibility, and its application resulted in improved maintenance of bone height compared with control sites. The Ti foam in a rod design exhibited bone ingrowth properties suitable for further exploration in other experimental situations.
Fibrosis and Loss of Smooth Muscle in the Corpora Cavernosa Precede Corporal Veno-Occlusive Dysfunction (CVOD) Induced by Experimental Cavernosal Nerve Damage in the Rat
Authors: Ferrini Monica G. , Kovanecz Istvan , Sanchez Sandra , Umeh Chiome , Rajfer Jacob , Gonzalez-Cadavid Nestor F.
Published: December 2008

Introduction

Corporal veno-occlusive dysfunction (CVOD), which usually is associated with a loss of smooth muscle cells (SMC) and an increase in fibrosis within the corpora cavernosa, can be induced by an injury to the cavernosal nerves. The corporal tissue expresses inducible nitric oxide synthase (iNOS), presumably as an antifibrotic and SMC-protective response.

Aims

We studied the temporal relationship in the corpora between the expression of iNOS, other histological and biochemical changes, and the development of CVOD, after bilateral cavernosal nerve resection (BCNR) in the rat.

Methods

Rats underwent either BCNR or sham operation. Cavernosometry was performed 1, 3, 7, 15, 30, and 45 days (N = 8/groups) after surgery. Penile tissue sections were subjected to Masson trichrome staining for SMC and collagen, and immunodetection for alpha smooth muscle actin, iNOS, neuronal NOS (nNOS), endothelial NOS (eNOS), proliferating cell nuclear antigen (PCNA), and terminal transferase dUTP nick end labeling (TUNEL). Quantitative western blot analysis was done in homogenates.

Main Outcome Measures

Time course on the development of fibrosis and CVOD.

Results

Following BCNR, CVOD was detectable 30 days later, and it became more pronounced by 45 days. In contrast, the SMC/collagen ratio in the BCNR corpora was reduced at 7 days and bottomed at 30 and 45 days, due in part to the reduction of SMC, presumably caused by an increase in apoptosis peaking at 3 days. PCNA also peaked at 3 days, but then decayed. nNOS was reduced early (3–7 days) and disappeared at 30 days, whereas eNOS was not affected. iNOS was induced at day 3, and steadily increased peaking at 30 days.

Conclusions

CVOD develops in the BCNR rat as a result of the early loss of corporal SMC by the neuropraxia-induced apoptosis, which the initial cell replication response cannot counteract, followed by fibrosis. The time course of iNOS induction supports the antifibrotic role of iNOS.
Cavernous Artery Intima-Media Thickness: A New Parameter in the Diagnosis of Vascular Erectile Dysfunction
Authors: Caretta Nicola , Palego Pierfrancesco , Schipilliti Mirko , Ferlin Alberto , Di Mambro Antonella , Foresta Carlo
Published: December 2008

Introduction

A precise characterization of erectile dysfunction (ED) of vascular origin has not yet been achieved. Although cavernous peak systolic velocity (PSV) is generally considered a major parameter, it has many false positives and negatives because of anatomic variations of the cavernous artery course, challenging site of sampling, insufficient caracterization of an early phase of vascular disease, and significant influence of adrenergic tone.

Aim

We performed a high magnification ultrasonographic study in order to compare functional and morphological parameters of the cavernous artery to PSV and their relation with penile and systemic atherosclerosis.

Methods

A total of 109 subjects (84 ED patients and 25 controls) evaluated in our andrological center from March 2007 to January 2008 were enrolled in the study.

Main Outcome Measures

All subjects underwent medical history, erectile function domain of the International Index of Erectile Function, physical examination, routine and sex hormone blood tests, and high resolution echo color doppler evaluation of carotid, femoral and penile districts (acceleration time, intima media thickness [IMT], intima adventitia thickness, caliper before and after intracavernous alprostadil injection [Δ-cavernous calliper]).

Results

Cavernous parameters were significantly different between ED and controls. Multivariate model showed that IMT was the only predicting parameter for ED of vascular origin. Cavernous IMT showed a strong direct correlation with carotid and femoral IMT. ED patients with two or more cardiovascular risk factors had a significantly higher cavernous IMT.

Conclusions

An increased cavernous IMT (≥0.3 mm) might predict ED of vascular origin with more accuracy than PSV and could be a sensitive predictor also for systemic atherosclerosis at an earlier phase.
State Ritual in Late Imperial China
Authors: Pidhainy Ihor
Published: December 2008

Until recently scholars have tended to view the Chinese imperial tradition from a human‐centred perspective. However, in the last two decades, the importance of ritual and state religion in imperial China has become better appreciated and more fully explored. This article focuses on research of late imperial China, from the tenth century to the beginning of the twentieth century, with a particular focus on the last two dynasties: the Ming (1368–1643) and Qing (1644–1911). This article is divided into four sections: a definition of Chinese ritual and its essential texts; its relationship to other religious ritual systems (Buddhism, Daoism and folk religions); an examination of three central reign periods: Hongwu (Zhu Yuanzhang, reign 1368–1398), Jiajing (Zhu Houcong, reign 1521–1567), and Qianlong (Hongli, reign 1735–1796); and the aesthetics of state ritual, including literature, art history and music.
Factors in Various Fractions of Meat Homogenates That Affect the Oxidative Stability of Raw Chicken Breast and Beef Loin
Authors: Min B. , Ahn D.U.
Published: December 2008

ABSTRACT:  The fractions of meat homogenates were analyzed to find the factors that determine the susceptibility of raw chicken breast and beef loin to lipid oxidation. The fractions used in this study were meat homogenate, precipitate, and supernatant of homogenate after centrifugation, and high and low molecular weight fractions from the supernatant. Chicken breast showed greater oxidative stability than beef loin during 10‐d storage (P < 0.05). All fractions from chicken breast showed lower amounts of free ionic iron and myoglobin and higher total antioxidant capacity (TAC) than those from beef loin during storage. The TAC level of chicken breast maintained during storage. This suggested that the oxidative stability of chicken breast was ascribed to high, stable total antioxidant capacity with low level of catalysts for lipid oxidation. The water‐soluble high molecular weight fraction, which contained myoglobin, was responsible for the high lipoxygenase‐like activity and lipid oxidation potential (LOP) in beef loin. TAC in all fractions from beef loin decreased during storage. This suggested that high myoglobin content in beef loin caused the imbalance between pro‐ and antioxidant factors leading to the high susceptibility of beef loin to lipid oxidation. Myoglobin served a major source of catalysts, ferrylmyoglobin, hematin, and/or free ionic iron, for lipid oxidation.
Effects of Drying Temperature and Surface Characteristics of Vegetable on the Survival of Salmonella
Authors: Hawaree N. , Chiewchan N. , Devahastin S.
Published: December 2008

ABSTRACT:  The heat resistance of Salmonella Anatum inoculated on the surface of a model vegetable as affected by hot‐air drying temperature (50 to 70 °C) and surface characteristics was determined in this study. Cabbage was selected as a model vegetable to demonstrate the effect of topographical feature of vegetable surface on the Salmonella attachment ability. An image analysis technique was developed to monitor the change of cabbage surface during drying and the specific surface characteristics were described in terms of the roughness factor (R). It was found that the water activity of the vegetable decreased while R‐value increased with longer drying time and higher drying temperature. However, the changes of both parameters during drying did not show a significant effect on the susceptibility of Salmonella attached on the cabbage surface. Drying temperature was found to be a major factor influencing the heat resistance of Salmonella during drying.
Heat Pretreatment Alleviates UV‐B Toxicity in the CyanobacteriumAnabaena doliolum: A Proteomic Analysis of Cross Tolerance
Authors: Mishra Yogesh , Chaurasia Neha , Rai Lal Chand
Published: December 2008

This study offers proteomic elucidation of heat pretreatment‐induced alleviation of UV‐B toxicity inAnabaena doliolum. Heat‐pretreated cells exposed to UV‐B showed improved activity of PSI, PSII, whole chain,14C fixation, ATP and NADPH contents compared to UV‐B alone. Proteomic analysis using two‐dimensional gel electrophoresis (2‐DE), MALDI‐TOF MS/MS and reverse transcription polymerase chain reaction (RT‐PCR) of UV‐B and heat pretreatment followed by UV‐B–treated cells exhibited significant and reproducible alterations in nine proteins homologous to phycocyanin‐α‐chain (PC‐α‐chain), phycoerythrocyanin‐α‐chain (PEC‐α‐chain), hypothetical protein alr0882, phycobilisome core component (PBS‐CC), iron superoxide dismutase (Fe‐SOD), fructose‐1,6‐bisphosphate aldolase (FBA), nucleoside diphosphate kinase (NDPK), phosphoribulokinase (PRK) and ribulose‐1,5‐bisphosphate carboxylase/oxygenase (RuBisCo) large chain. Except the PEC‐α‐chain, hypothetical protein alr0882 and PBS‐CC, all other proteins showed upregulation at low doses of UV‐B (U2) and significant downregulation at higher doses of UV‐B (U5). The disruption of redox status, signaling, pentose phosphate pathway and Calvin cycle appears to be due to the downregulation of Fe‐SOD, NDPK, FBA, PRK and RuBisCo thereby leading to the death ofAnabaena. In contrast to this, the upregulation of all the above proteins in heat‐pretreated cells, harboring different heat shock proteins (HSPs) like 60, 26 and 16.6, followed by UV‐B treatment than only the UV‐B–treated ones suggests a protective role of HSPs in mitigating UV‐B toxicity.
Entrepreneurs and new ideas
Authors: Biais Bruno , Perotti Enrico
Published: December 2008

We study how early‐stage new ideas are turned into successful businesses. Even promising ideas can be unprofitable if they fail on one dimension, such as technical feasibility, correspondence to market demand, legality, or patentability. To screen good ideas, the entrepreneur needs to hire experts who evaluate the idea along their dimensions of expertise. Sharing the idea, however, creates the risk that the expert would steal it. Yet, the idea‐thief cannot contact any other expert, lest he should in turn steal the idea. Thus, stealing leads to incomplete screening and is unattractive if the information of the other expert is critical and highly complementary. In such cases, the entrepreneur can form a partnership with the experts, thus granting them the advantage of accessing each other's information. Yet, very valuable ideas cannot be shared because it is too tempting to steal them.
Experimental Study on the Stabilization of Small-Bore Journal Bearings by Controlling Starved Lubrication and Bearing Orientation Angle
Authors: Hashimoto Hiromu , Ochiai Masayuki
Published: December 2008

Journal bearings are widely used for supporting high-speed rotating machinery, such as turbine, compressor, and HDD spindle, because of their high load carrying capacity, stability, and durability. Recently, the engineering trend is oriented to higher speed and smaller sizes of rotating machinery, and then it is important to enhance stabilities for the small-bore journal bearings. Tilting pad journal bearing is generally used for high-speed rotating machineries because of their advantages of stabilization. However, there are some problems using compact size rotating machineries for their high manufacturing cost and complicated structure. Therefore, it is necessary to enhance the stability of more simple bearings compared with tilting pad bearing in order to use for small-size rotating machinery. This paper describes the stabilization method of the small-bore journal bearing based on the combination mechanism with starved lubrication and orientation angle change. It is found that the stabilization of small-bore journal bearings is improved drastically by hybrid lubrication combining these two kinds of mechanism.
On a Simplified Model for Numerical Simulation of Wear During Dry Rolling Contacts
Authors: Chevalier L. , Eddhahak-Ouni A. , Cloupet S.
Published: December 2008

We deal with rolling contact between quasi-identical bodies. As normal and tangential problems are uncoupled in that case, the simplified approach to determine contact area and normal loading distribution for rolling contact problems is presented in Sec. 2. In Sec. 3, the solution of the tangential problem is used to update the rolling profiles and enables to follow the wear evolution versus time. The method used to solve the normal problem is called semi-Hertzian approach with diffusion. It allows fast determination of the contact area for non-Hertzian cases. The method is based on the geometrical indentation of bodies in contact: The contact area is found with correct dimensions but affected by some irregularities coming from the curvature’s discontinuity that may arise during a wear process. Diffusion between independent stripes smoothes the contact area and the pressure distribution. The tangential problem is also solved on each stripe of the contact area using an extension of the simplified approach developed by Kalker and called FASTSIM. At the end, this approach gives the dissipated power distribution in the contact during rolling and this power is related to wear by Archard’s law. This enables the profiles of the bodies to be updated and the evolution of the geometry to be followed.
Determination of absorbed dose in water at the reference point for an HDR brachytherapy source using a Fricke system
Authors: Austerlitz C. , Mota H. C. , Sempau J. , Benhabib S. M. , Campos D. , Allison R. , deAlmeida C. E. , Zhu D. , Sibata C. H.
Published: December 2008

A ring‐shaped Fricke device was developed to measure the absolute dose on the transverse bisector of a high dose rate (HDR) source at from its center in water, . It consists of a polymethylmethacrylate (PMMA) rod (axial axis) with a cylindrical cavity at its center to insert the radioactive source. A ring cavity around the source with thickness and height is centered at from the central axis of the source. This ring cavity is etched in a disk shaped base with diameter and thickness. The cavity has a wall around it thick. This ring is filled with Fricke solution, sealed, and the whole assembly is immersed in water during irradiations. The device takes advantage of the cylindrical geometry to measure . Irradiations were performed with a Nucletron microselectron HDR unit loaded with an Alpha Omega radioactive source. A Spectronic® 1001 spectrophotometer was used to measure the optical absorbance using a quartz cuvette with light pathlength. The PENELOPE Monte Carlo code (MC) was utilized to simulate the Fricke device and the Alpha Omega source in detail to calculate the perturbation introduced by the PMMA material. A NIST traceable calibrated well type ionization chamber was used to determine the air‐kerma strength, and a published dose‐rate constant was used to determine the dose rate at the reference point. The time to deliver to the reference point was calculated. This absorbed dose was then compared to the absorbed dose measured by the Fricke solution. Based on MC simulation, the PMMA of the Fricke device increases the by 2.0%. Applying the corresponding correction factor, the value assessed with the Fricke device agrees within 2.0% with the expected value with a total combined uncertainty of 3.43% . The Fricke device provides a promising method towards calibration of brachytherapy radiation sources in terms of and audit HDR source calibrations.
Mean glandular dose estimation using MCNPX for a digital breast tomosynthesis system with tungsten/aluminum and tungsten/ x‐ray anode‐filter combinations
Authors: Ma Andy K. W. , Darambara Dimitra G. , Stewart Alexander , Gunn Spencer , Bullard Edward
Published: December 2008

Breast cancer screening with x‐ray mammography, using one or two projection images of the breast, is an indispensible tool in the early detection of breast cancer in women. Digital breast tomosynthesis (DBT) is a 3D imaging technique that promises higher sensitivity and specificity in breast cancer screening at a similar radiation dose to conventional two‐view screening mammography. In DBT a 3D volume is reconstructed with anisotropic voxels from a limited number of x‐ray projection images acquired over a limited angle. Although the benefit of early cancer detection through screening mammography outweighs the potential risks associated with radiation, the radiation dosage to women in terms of mean glandular dose (MGD) is carefully monitored. This work studies the MGD arising from a prototype DBT system under various parameters. Two anode/filter combinations ( and ) were investigated; the tube potential ranges from ; and the breast size varied between 4 and chest wall‐to‐nipple distance and between 3 and compressed breast thickness. The dosimetric effect of breast positioning with respect to the imaging detector was also reviewed. It was found that the position of the breast can affect the MGD by as much as 5% to 13% depending on the breast size.
Direct‐conversion flat‐panel imager with avalanche gain: Feasibility investigation for HARP‐AMFPI
Authors: Wronski M. M. , Rowlands J. A.
Published: December 2008

The authors are investigating the concept of a direct‐conversion flat‐panel imager with avalanche gain for low‐dose x‐ray imaging. It consists of an amorphous selenium photoconductor partitioned into a thick drift region for x‐ray‐to‐charge conversion and a relatively thin region called high‐gain avalanche rushing photoconductor (HARP) in which the charge undergoes avalanche multiplication. An active matrix of thin film transistors is used to read out the electronic image. The authors call the proposed imager HARP active matrix flat panel imager (HARP‐AMFPI). The key advantages of HARP‐AMFPI are its high spatial resolution, owing to the direct‐conversion layer, and its programmable avalanche gain, which can be enabled during low dose fluoroscopy to overcome electronic noise and disabled during high dose radiography to prevent saturation of the detector elements. This article investigates key design considerations for HARP‐AMFPI. The effects of electronic noise on the imaging performance of HARP‐AMFPI were modeled theoretically and system parameters were optimized for radiography and fluoroscopy. The following imager properties were determined as a function of avalanche gain: (1) the spatial frequency dependent detective quantum efficiency; (2) fill factor; (3) dynamic range and linearity; and (4) gain nonuniformities resulting from electric field strength nonuniformities. The authors results showed that avalanche gains of 5 and 20 enable x‐ray quantum noise limited performance throughout the entire exposure range in radiography and fluoroscopy, respectively. It was shown that HARP‐AMFPI can provide the required gain while maintaining a 100% effective fill factor and a piecewise dynamic range over five orders of magnitude (/frame). The authors have also shown that imaging performance is not significantly affected by the following: electric field strength nonuniformities, avalanche noise for x‐ray energies above and direct interaction of x rays in the gain region. Thus, HARP‐AMFPI is a promising flat‐panel imager structure that enables high‐resolution fully quantum noise limited x‐ray imaging over a wide exposure range.
Monte Carlo evaluation of a treatment planning system for helical tomotherapy in an anthropomorphic heterogeneous phantom and for clinical treatment plans
Authors: Zhao Ying‐Li , Mackenzie M. , Kirkby C. , Fallone B. G.
Published: December 2008

Helical tomotherapy is an increasingly common form of intensity modulated radiation therapy that allows for image guided adaptive radiotherapy. Its treatment planning system (TPS) uses a convolution superposition algorithm for dose distribution calculations. The accuracy of this algorithm in the presence of heterogeneities was evaluated against Monte Carlo (MC) calculations and measurements. This work performed BEAMnrc‐and DOSXYZnrc‐based MC dose calculations of tomotherapy deliveries to a CIRS anthropomorphic heterogeneous phantom with typical clinical inverse planning and delivery settings. Point measurements with A1SL ion chambers and relative measurements with Kodak EDR2 film were carried out in the phantom. The experimental results were used to evaluate both the TPS and MC dose calculations. Furthermore, the dose distribution for a clinical head‐and‐neck cancer plan was calculated on the TPS and MC systems. The results support this MC system as a viable option for the accurate simulation of the tomotherapy process in the presence of heterogeneities where direct measurement may not be practical. Ion chamber measurements in the CIRS phantom suggested the TPS has an average relative difference of 2.3%, with the largest difference being in one of the organs at risk. The MC system accurately predicted the dose to these measurement points within statistical uncertainty. The film measurements in the CIRS phantom demonstrated 90.7% (of pixels) agreed with the MC system using a acceptance criteria, where only 50.3% agreed with the TPS. In the clinical head‐and‐neck cancer plan evaluation where MC served as a reference against which to compare the TPS result, an average of 92.7% of the voxels within volumes of interest passed a criteria. The PTV54 region showed the worst agreement with 85.4% of the volume passing the criteria. In general, the criterion was found to be a challenge for the TPS in the presence of lung inhomogeneity.
Cascaded systems analysis of the 3D noise transfer characteristics of flat‐panel cone‐beam CT
Authors: Tward Daniel J. , Siewerdsen Jeffrey H.
Published: December 2008

The physical factors that govern 2D and 3D imaging performance may be understood from quantitative analysis of the spatial‐frequency‐dependent signal and noise transfer characteristics [e.g., modulation transfer function (MTF), noise‐power spectrum (NPS), detective quantum efficiency (DQE), and noise‐equivalent quanta (NEQ)] along with a task‐based assessment of performance (e.g., detectability index). This paper advances a theoretical framework based on cascaded systems analysis for calculation of such metrics in cone‐beam CT (CBCT). The model considers the 2D projection NPS propagated through a series of reconstruction stages to yield the 3D NPS and allows quantitative investigation of tradeoffs in image quality associated with acquisition and reconstruction techniques. While the mathematical process of 3D image reconstruction is deterministic, it is shown that the process is irreversible, the associated reconstruction parameters significantly affect the 3D DQE and NEQ, and system optimization should consider the full 3D imaging chain. Factors considered in the cascade include: system geometry; number of projection views; logarithmic scaling; ramp, apodization, and interpolation filters; 3D back‐projection; and 3D sampling (noise aliasing). The model is validated in comparison to experiment across a broad range of dose, reconstruction filters, and voxel sizes, and the effects of 3D noise correlation on detectability are explored. The work presents a model for the 3D NPS, DQE, and NEQ of CBCT that reduces to conventional descriptions of axial CT as a special case and provides a fairly general framework that can be applied to the design and optimization of CBCT systems for various applications.