bluuebunny/crossref_metadata_2025 huggingface dataset:
The Socioeconomic Attainments of Second‐Generation Cambodian, Hmong, Laotian, and Vietnamese Americans*
Authors: Sakamoto Arthur , Woo Hyeyoung
Published: January 2007

We investigate the socioeconomic attainments of second‐generation Cambodian, Hmong, Laotian, and Vietnamese Americans. Using 2000 Census data, we focus on education, wages, and managerial/professional employment relative to African Americans and whites. The second‐generation Vietnamese stand out as having extraordinarily high average values on these indicators. By contrast, the socioeconomic attainments of second‐generation Cambodians, Hmong, and Laotians tend to be closer to those of African Americans except among those second‐generation Southeast Asians who are clearly part of the earlier (i.e., Wave 1) immigration stream that tended to have somewhat higher socioeconomic origins. The most disadvantaged groups are non‐Wave 1 second‐generation Laotians and Cambodian women, particularly in terms of the process of educational attainment. The results are interpreted as indicating the importance of class origins and immigrant selectivity.
US and Japan Should Engage Rising China and India
Authors: DAM KENNETH , HATAKEYAMA NOBORU
Published: January 2007

Globalization may yet repeal the Biblical adage that the poor will always be with us. But for now there are enough losers to go along with the winners that a slide back toward fragmentation and protectionism is a distinct possibility, as was also the case at the turn of the 20th century. Our contributors in this section offer their advice on how to make globalization work for everyone.
New Links With China Are Key to Japan's Security
Authors: WATANABE TSUNEO
Published: January 2007

Never before in history have China and Japan been great powers at the same time. Today they must figure out how to live together as equals. The promise of mutual prosperity ties them together; the remembrance of bad things past pushes them apart.

If that wary dance were not complicated enough, a nuclear provocateur from neighboring North Korea intrudes. A legendary figure of Japan's post‐war miracle, Tsuneo Watanabe, weighs in on these big questions. Hans Blix, a former UN arms inspector and the former South Korean prime minister and Nobel laureate, Kim Dae Jung, address the North Korean conundrum.
The Fall: Consequences of US Withdrawal From Iraq
Authors: VAN CREVELD MARTIN
Published: January 2007

There is no big anti‐war movement in the United States against Iraq like there was against Vietnam. But the people have finally spoken against President Bush's Iraq policy by resoundingly returning a Democratic majority to Congress. Henry Kissinger, eminence gris of American diplomacy, ponders whether this means a “return to realism.” The military historian Martin van Creveld looks at what American withdrawal would mean.
Fluoride ingestion from toothpaste and diet in 1‐ to 3‐year‐old Brazilian children
Authors: De Almeida Beatriz Simões , Da Silva Cardoso Vanessa Eid , Buzalaf Marília Afonso Rabelo
Published: January 2007

Abstract –  Objective:  This study estimated the total daily fluoride intake of 1‐ to 3‐year‐old children from diet and dentifrice. The constituents of the diet were divided into solids, water, milk, and other beverages, which were analyzed separately. The correlation between fingernail fluoride concentrations and the total daily fluoride intake by children was also investigated.

Methods:  Thirty‐three children, living in a fluoridated area, participated in the study. Fluoride intake from diet was monitored by the ‘duplicate plate’ method, investigating the different constituents of the diet. Fluoride ingested from dentifrice was determined by subtracting the amount of fluoride recovered after brushing from the amount originally placed onto the child's toothbrush. Fingernails were clipped and collected on three occasions. Fluoride was analyzed with the ion‐specific electrode, after hexamethyldisiloxane‐facilitated diffusion. Data were tested by anova and Tukey's post hoc tests, Student's t‐tests and linear regression (P < 0.05).

Results:  Mean (±SD) fluoride intake from diet and dentifrice was 0.025 ± 0.013 and 0.106 ± 0.085 mg/kg body weight/day, respectively, totaling 0.130 mg/kg body weight/day. A strong positive correlation (r = 0.971, P < 0.0001) was seen between the amount of dentifrice loaded onto the brush (0.49 ± 0.30 g) and the amount of fluoride ingested during each tooth brushing (0.59 ± 0.45 mg). Among the constituents of the diet, water and milk had a significantly higher contribution to the fluoride intake (0.18 ± 0.11 mg/day, P < 0.0001), when compared with solids (0.07 ± 0.05 mg/day) and other beverages (0.07 ± 0.04 mg/day). Mean (±SD) fingernail fluoride concentration on the three dates of collection was 3.11 ± 1.14, 2.22 ± 1.47 and 3.53 ± 1.40 μg F/g. There was no significant correlation between fingernail fluoride concentration and the total fluoride intake.

Conclusions:  Most of the children are exposed to a daily fluoride intake above the suggested threshold for dental fluorosis. The dentifrice alone is responsible for an average of 81.5% of the daily fluoride intake, while among the constituents of the diet, water and milk are the most important contributors. In addition, small variations in daily fluoride intake cannot be detected in fingernails.
From victim blaming to upstream action: tackling the social determinants of oral health inequalities
Authors: Watt Richard Geddie
Published: January 2007

Abstract – The persistent and universal nature of oral health inequalities presents a significant challenge to oral health policy makers. Inequalities in oral health mirror those in general health. The universal social gradient in both general and oral health highlights the underlying influence of psychosocial, economic, environmental and political determinants. The dominant preventive approach in dentistry, i.e. narrowly focusing on changing the behaviours of high‐risk individuals, has failed to effectively reduce oral health inequalities, and may indeed have increased the oral health equity gap. A conceptual shift is needed away from this biomedical/behavioural ‘downstream’ approach, to one addressing the ‘upstream’ underlying social determinants of population oral health. Failure to change our preventive approach is a dereliction of ethical and scientific integrity. A range of complementary public health actions may be implemented at local, national and international levels to promote sustainable oral health improvements and reduce inequalities. The aim of this article is to stimulate discussion and debate on the future development of oral health improvement strategies.
Testing the effect of including oral health in general health checks for elderly patients in medical practice – a randomized controlled trial
Authors: Lowe C. , Blinkhorn A. S. , Worthington H. V. , Craven R.
Published: January 2007

Abstract –  Aim:  To test the feasibility and effectiveness of an oral health referral process for elderly patients (aged 75 years or over) attending a preventive health check (PHC) with their general medical practitioner.

Objectives:  To evaluate the effectiveness of the process in increasing dental attendance at baseline and 6 months after the intervention. To identify key characteristics of those who accepted an oral health visit (OHV). To determine the proportion of people attending the OHV who required treatment and subsequently attended a dentist.

Setting:  Three general medical practices in east Cheshire, UK.

Design:  A randomized controlled trial.

Method:  Elderly patients attending their general medical practice for PHCs were randomly assigned to a test group, who were invited to attend for an OHV, and to a control group, who received no intervention. Six months after the PHC the effectiveness of the process was measured.

Results:  Some 50% of those invited for an OHV accepted. Those accepting were more likely to be edentulous, wear dentures or have a current oral health problem, than those declining. Regression analysis showed the best predictors of acceptance to be having a current dental problem or pain and not having a regular dentist. The mean time since their last dental visit was 8.1 years which was significantly longer than those declining the OHV. 63% of individuals attending the OHV were assessed as having a realistic treatment need and 70% of those referred went on to complete the course of treatment. In the test group a highly significant increase in reported dental visiting was found at sixth month evaluation. The primary care staff were happy to include the dental checklist and felt it was a valuable addition to the PHC.

Conclusions:  The offer of an OHV was taken up most readily by those with current oral problems, or pain and those with no regular dentist. The inclusion of a dental checklist within the PHC for elderly patients together with help with arranging a dental appointment shows promise as a way of ensuring the dental needs of this group are met.
Molecular imprinting of cyclodextrin glycosyltransferases from Paenibacillus sp. A11 and Bacillus macerans with γ‐cyclodextrin
Authors: Kaulpiboon Jarunee , Pongsawasdi Piamsook , Zimmermann Wolfgang
Published: January 2007

Cyclodextrin glycosyltransferase catalyzes the formation of a mixture of cyclodextrins from starch by an intramolecular transglycosylation reaction. To manipulate the product specificity of the Paenibacillus sp. A11 and Bacillus macerans cyclodextrin glycosyltransferases towards the preferential formation of γ‐cyclodextrin (CD8), crosslinked imprinted proteins of both cyclodextrin glycosyltransferases were prepared by applying enzyme imprinting and immobilization methodologies. The crosslinked imprinted cyclodextrin glycosyltransferases obtained by imprinting with CD8 showed pH and temperature optima similar to those of the native and immobilized cyclodextrin glycosyltransferases. However, the pH and temperature stability of the immobilized and crosslinked imprinted cyclodextrin glycosyltransferases were higher than those of the native cyclodextrin glycosyltransferases. When the catalytic activities of the native, immobilized and crosslinked imprinted cyclodextrin glycosyltransferases were compared, the efficiency of the crosslinked imprinted enzymes for CD8 synthesis was increased 10‐fold, whereas that for cyclodextrin hydrolysis was decreased. Comparison of the product ratios by high‐performance anion exchange chromatography showed that the native cyclodextrin glycosyltransferases from Paenibacillus sp. A11 and Bacillus macerans produced CD6 : CD7 : CD8 : ≥ CD9 ratios of 15 : 65 : 20 : 0 and 43 : 36 : 21 : 0 after 24 h of reaction at 40 °C with starch substrates. In contrast, the crosslinked imprinted cyclodextrin glycosyltransferases from Paenibacillus sp. A11 and Bacillus macerans produced cyclodextrin in ratios of 15 : 20 : 50 : 15 and 17 : 14 : 49 : 20, respectively. The size of the synthesis products formed by the crosslinked imprinted cyclodextrin glycosyltransferases was shifted towards CD8 and ≥ CD9, and the overall cyclodextrin yield was increased by 12% compared to the native enzymes. The crosslinked imprinted cyclodextrin glycosyltransferases also showed higher stability in organic solvents, retaining 85% of their initial activity after five cycles of synthesis reactions.
DIFFERENCE TEST SENSITIVITY: COGNITIVE CONTRAST EFFECTS
Authors: LEE H.‐S. , O'MAHONY M.
Published: January 2007

Judges performed 3‐AFC tests between “threshold” concentrations of NaCl solutions and purified water stimuli. For some 3‐AFCs, NaCl was the odd stimulus (S‐odd); in others, water was the odd stimulus (W‐odd). In one condition, interstimulus rinses were different from the stimuli; in a second condition they were the same. The 3‐AFCs in which the interstimulus rinses were different from the stimuli yielded a higher d′. When interstimulus rinses were the same as the stimuli, S‐odd 3‐AFCs had a higher d′ than W‐odd 3‐AFCs. The same was not true when the interstimulus rinses were different from the stimuli. Sequential Sensitivity Analysis and the conditional stimulus model did not furnish a complete explanation for these data. A consideration of additional cognitive contrast effects yielded a possible explanation.
IMPACT OF DRYING AND STORAGE TIME ON SENSORY CHARACTERISTICS OF ROSEMARY (ROSMARINUS OFFICINALIS L.)
Authors: DÍAZ‐MAROTO M.C. , PÉREZ‐COELLO M.S. , SÁNCHEZ‐PALOMO E. , GONZÁLEZ VIÑAS M.A.
Published: January 2007

The effect of drying treatment on the aroma characteristics of rosemary (Rosmarinus Officinalis L.) was studied using the Quantitative Descriptive Analysis (QDA) with a trained panel and by Free Choice Profiling (FCP) analysis with a consumer group. Differences between samples were observed after applying Principal Component Analysis to the QDA data and Generalized Procrustes Analysis to the FCP data. The highest differences were found between fresh rosemary samples and dried samples. However, dried samples (obtained by oven‐drying at 45C and commercial samples purchased at the markets and stored for 6 months) showed significant differences in their sensory characteristics. Odor detection thresholds of the fresh rosemary leaves were calculated in water and in potato sauce, and significant differences were found.
SENSORY CHARACTERISTICS OF EZINE CHEESE
Authors: KARAGUL‐YUCEER YONCA , ISLETEN MUGE , UYSAL‐PALA CIGDEM
Published: January 2007

Ezine cheese is a full‐fat, white pickled cheese ripened in tinplate containers. A mixture of milks from goat, sheep and cow is used to make Ezine cheese. It has its own characteristic taste and aroma that differ from other white cheeses. In this study, the chemical composition and sensory attributes of Ezine cheese were characterized. A descriptive sensory evaluation technique was used to determine flavor and texture characteristics. Representative Ezine cheeses (22) were provided by local producers. A highly trained (n = 9) panel generated the descriptive terms and identified the references. Fourteen flavors and 10 texture terms were developed to describe Ezine cheese flavor and texture. Some characteristic flavor and taste descriptors for Ezine cheese were free fatty acids, cooked, creamy, whey‐like, goaty, salty and sour. Cheese texture was evaluated using hand, mouth and residual techniques. Texture analysis indicated that Ezine cheese had soft and semi‐hard texture properties. In general, most of the Ezine cheeses showed similarities in terms of hand firmness, mouth firmness, fracturability and number of particles attributes.
Depressed contractile reserve and impaired calcium handling of cardiac myocytes from chronically unloaded hearts are ameliorated with the administration of physiological treatment dose of T3 in rats
Authors: Minatoya Y. , Ito K. , Kagaya Y. , Asaumi Y. , Takeda M. , Nakayama M. , Takahashi J. , Iguchi A. , Shirato K. , Shimokawa H.
Published: January 2007

Aim:  Chronic cardiac unloading causes a time‐dependent upregulation of phospholamban (PLB) and depression of myocyte contractility in normal rat hearts. As thyroid hormone is known to decrease PLB expression, we examined whether thyroid hormone restores the depressed contractile performance of myocytes from chronically unloaded hearts.

Methods:  Cardiac unloading was induced by heterotopic heart transplantation in isogenic rats for 5 weeks. Animals were treated with either vehicle or physiological treatment dose of 3,5,3′‐triiodo‐l‐thyronine (T3) that does not cause hyperthyroidism for the last 3 weeks (n = 20 each).

Results:  In vehicle‐treated animals, myocyte relaxation and [Ca2+]i decay were slower in unloaded hearts than in recipient hearts. Myocyte shortening in response to high [Ca2+]o was also depressed with impaired augmentation of peak‐systolic [Ca2+]i in unloaded hearts compared with recipient hearts. In vehicle‐treated rats, protein levels of PLB were increased by 136% and the phosphorylation level of PLB at Ser16 were decreased by 32% in unloaded hearts compared with recipient hearts. By contrast, in the T3‐treated animals, the slower relaxation, delayed [Ca2+]i decay, and depressed contractile reserve in myocytes from unloaded hearts were all returned to normal levels. Furthermore, in the T3‐treated animals, there was no difference either in the PLB protein level or in its Ser16‐phosphorylation level between unloaded and recipient hearts.

Conclusion:  These results suggest that the treatment with physiological treatment dose of thyroid hormone rescues the impaired myocyte relaxation and depressed contractile reserve at least partially through the restoration of PLB protein levels and its phosphorylation state in chronically unloaded hearts.
Hydronephrosis causes salt‐sensitive hypertension and impaired renal concentrating ability in mice
Authors: Carlström M. , Sällström J. , Skøtt O. , Larsson E. , Wåhlin N. , Persson A. E. G.
Published: January 2007

Aim:  Hypertension is a common disease in the industrialized world and approximately 5% of all cases are secondary to kidney malfunction. We have recently shown that hydronephrosis due to partial unilateral ureteral obstruction (PUUO) causes salt‐sensitive hypertension in rats. The mechanisms are still unclear, but appear to be intrarenal and primarily located to the diseased kidney. In the present study, we have developed a model for PUUO to study if hydronephrotic mice develop salt‐sensitive hypertension.

Methods:  PUUO was created in 3‐week‐old mice (C57bl/6J). Blood pressure and heart rate were measured telemetrically in adult animals on normal and high salt diets. Metabolism cages were used to study the renal excretion of electrolytes and water. Plasma samples for renin analysis were collected and renal histological changes were evaluated.

Results:  All hydronephrotic animals developed salt‐sensitive hypertension that correlated to the degree of hydronephrosis. In hydronephrotic animals, blood pressure increased from 114 ± 1 mmHg on normal salt diet to 120 ± 2 mmHg on high salt diet, compared with 103 ± 1 to 104 ± 1 in controls. Hydronephrotic animals showed increased diuresis and reduced ability to regulate electrolyte concentration. No differences in plasma renin concentration were found between the groups. The parenchymal weight and glomerular area of contralateral kidneys were significantly increased in the hydronephrotic animals. Histopathology of the hydronephrotic kidneys displayed areas with fibrosis, inflammation and glomerular changes.

Conclusion:  This study provides a model for PUUO in mice and demonstrates the presence of salt‐sensitive hypertension and an impaired renal concentrating ability in mice which has not been described before.
Characterization of GLUT4 and calpain expression in healthy human skeletal muscle during fasting and refeeding
Authors: Norton L. , Parr T. , Bardsley R. G. , Ye H. , Tsintzas K.
Published: January 2007

Aims:  Calpain‐10 and calpain‐3 and the diabetes ankyrin repeat protein (DARP) have all been linked to insulin resistance and type 2 diabetes. We set out to measure the expression of these genes in human skeletal muscle and relate them to functional measurements of insulin action during fasting (which induces insulin resistance) and refeeding (which reverses it).

Methods:  Ten healthy male volunteers underwent 48 h of starvation followed by 24 h of high carbohydrate refeeding. On three occasions, before and after starvation and after refeeding, subjects underwent a 16 min insulin tolerance test to quantify insulin sensitivity. Muscle biopsies were obtained before and after fasting and after refeeding for the analysis of calpain‐10 and calpain‐3, GLUT4 and DARP expression by Western blotting and real‐time PCR.

Results:  Fasting led to a marked reduction in whole body insulin sensitivity by approx. 45% (P < 0.01) and skeletal muscle GLUT4 gene expression by approx. 40% (P < 0.05). However, fasting had no effect on calpain‐10 and calpain‐3 mRNA or protein levels, or DARP mRNA expression. Refeeding only partly restored insulin sensitivity and GLUT4 gene expression to their pre‐fast values, but did not effect the expression of calpain‐10, calpain‐3 or DARP.

Conclusions:  These findings demonstrate that in healthy non‐diabetic humans induction of insulin resistance by fasting and its reversal by refeeding with a high CHO diet is mirrored by changes in skeletal muscle GLUT4 but not calpain‐10 and calpain‐3 expression.
Dantrolene, like fatigue, has a length‐dependent effect on submaximal force–length relationships of rat gastrocnemius muscle
Authors: MacNaughton M. B. , Campbell J. J. , MacIntosh B. R.
Published: January 2007

Aim:  Fatigue is length‐dependent; relative active force depression is greater when measured at short lengths than at long lengths. Several unsatisfactory mechanisms have been proposed to explain this length dependence of fatigue, including: damaged myofilaments, stretch of ‘in‐series’ structures, impaired t‐tubule conduction and reduced intensity of activation. Dantrolene targets the ryanodine receptors, inhibiting stimulation‐induced release of Ca2+. The purpose of this study was to determine if the force depression caused by dantrolene treatment also has a length dependence.

Methods:  Submaximal (single‐pulse, double‐pulse and 50 Hz stimulation) active force–length relationships were obtained from the medial gastrocnemius muscle of anaesthetized rats, before and after intravenous injection with dantrolene dissolved in propylene glycol.

Results:  Dantrolene treatment was sufficient to reduce twitch amplitude by 25%. Similar to the consequences of repetitive stimulation, dantrolene treatment caused the same decrease in absolute active force across a broad range of test lengths, for twitch, double‐pulse and 50 Hz contractions. Considering that active force is smaller at short lengths than at long lengths, this similar absolute force decrease represents a greater relative decrease at short lengths. Clearly, there is a length‐dependent impact of attenuated Ca2+ release by dantrolene on relative active force.

Conclusion:  This study demonstrates that there is a length dependence of force depression associated with decreased Ca2+ release due to dantrolene treatment; therefore, if fatigue is due to decreased Ca2+ release, then additional length‐dependent mechanisms are not required to explain the reported length dependence of force depression.
Distribution pattern of endangered bird species in China
Authors: LEI Fumin , ZHAO Hongfeng , YIN Zuohua
Published: January 2007

In this study, we determined six “hotspots” for avian biodiversity conservation in China. We analyzed the distribution patterns of 183 threatened bird species in China in conjunction with geographical data to produce a distribution map that shows the concentrations of threatened species. The six biodiversity hotspots are: the western Tianshan Mountains; the Qilian and Hengduan mountains; southern Anhui, southern Jiangsu, and the Zhejiang Hills; the Songliao Plain and the northern region of the North China Plain; the island of Taiwan; and the island of Hainan. Based on our analysis of a species–habitat matrix, species were determined to be distributed mainly in broadleaved forest, grassland and meadows, urban and agricultural areas, wetlands, and bush. Most species were commonly found to have a range of three to five different habitat types. Apart from the six biodiversity hotspots, six ecological clusters were determined. Protection strategies indicating different levels of habitat priority among the biodiversity hotspots were also recommended.
Reliable long‐lasting depression interacts with variable short‐term facilitation to determine corticostriatal paired‐pulse plasticity in young rats
Authors: Akopian G. , Walsh J. P.
Published: January 2007

Synaptic plasticity at corticostraital synapses is proposed to fine tune movment and improve motor skills. We found paired‐pulse plasticity at corticostriatal synapses reflected variably expressed short‐term facilitation blended with a consistent background of longer‐lasting depression. Presynaptic modulation via neuotransmitter receptor activation was ruled out as a mechanism for long‐lasting paired‐pulse depression by examining the effect of selective receptor antagonists. EPSC amplitude and paired‐pulse plasticity, however, was influenced by block of D2 dopamine receptors. Block of glutamate transport withl‐transdicarboxylic acid (PDC) reduced EPSCs, possibly through a mechanism of AMPA receptor desensitization. Removal of AMPA receptor desensitization with cyclothiazide reduced the paired‐pulse depression at long‐duration interstimulus intervals (ISIs), indicating that AMPA receptor desensitization participates in corticostriatal paired‐pulse plasticity. The low‐affinity glutamate receptor antagonistcis‐2,3‐piperidine dicarboxylic acid (PDA) increased paired‐pulse depression, suggesting that a presynaptic component also exists for long‐lasting paired‐pulse depression. Low Ca2+–high Mg2+or BAPTA‐AM dramatically reduced the amplitude of corticostriatal EPSCs and both manipulations increased the expression of facilitation and, to a lesser extent, they reduced long‐lasting paired‐pulse depression. EGTA‐AM produced a smaller reduction in EPSC amplitude and it did not alter paired‐pulse facilitation, but in contrast to low Ca2+and BAPTA‐AM, EGTA‐AM increased long‐lasting paired‐pulse depression. These experiments suggest that facilitation and depression are sensitive to vesicle depletion, which is dependent upon changes in peak Ca2+(i.e. low Ca2+–high Mg2+or BAPTA‐AM). In addition, the action of EGTA‐AM suggests that basal Ca2+regulates the recovery from long‐lasting paired‐pulse depression, possibly thourgh a Ca2+‐sensitive process of vesicle delivery.
Placental insufficiency decreases cell cycle activity and terminal maturation in fetal sheep cardiomyocytes
Authors: Louey Samantha , Jonker Sonnet S. , Giraud George D. , Thornburg Kent L.
Published: January 2007

Umbilicoplacental embolization (UPE) in sheep has been used to investigate the effects of placental insufficiency on fetal development. However, its specific effects on the heart have been little studied. The aim of this study was to determine the effects of placental insufficiency, induced by UPE, on cardiomyocyte size, maturation and proliferation. Instrumented fetal sheep underwent UPE for either 10 or 20 days. Hearts were collected at 125 ± 1 days (10 day group) or 136 ± 1 days (20 day group) of gestation (term ∼145 days). Cell size, maturational state (as measured by the proportion of binucleated myocytes) and cell cycle activity (as measured by positive staining of cells for Ki‐67) were determined in dissociated cardiomyocytes. UPE fetuses were hypoxaemic, but mean arterial pressures were not different from controls. UPE fetuses were lighter than control fetuses (10 days: −21%, P < 0.05; 20 days: −27%, P < 0.01) and had smaller hearts, but heart weight was appropriate for body weight. Neither lengths nor widths were different between control and UPE cardiomyocytes at either age. Ten days of UPE did not significantly alter the proportion of binucleated myocytes or cell cycle activity in either ventricle. However, 20 days of UPE reduced cell cycle activity in both ventricles by ∼70% (P < 0.05); the proportion of binucleated myocytes was also lower in UPE fetuses at this age (left ventricle: 31.1 ± 12.0 versus 46.0 ± 6.6%, P < 0.05; right ventricle: 29.4 ± 12.3 versus 46.3 ± 5.3%, P < 0.05). It is concluded that in the absence of fetal arterial hypertension, placental insufficiency is associated with substantially depressed growth of the heart through suppressed proliferation and maturation of cardiomyocytes.
Origin of sound‐evoked EMG responses in human masseter muscles
Authors: Deriu Franca , Ortu Enzo , Capobianco Saverio , Giaconi Elena , Melis Francesco , Aiello Elena , Rothwell John C. , Tolu Eusebio
Published: January 2007

Sound is a natural stimulus for both cochlear and saccular receptors. At high intensities it evokes in active masseter muscles of healthy subjects two overlapping reflexes: p11/n15 and p16/n21 waves, whose origin has not yet been demonstrated. Our purpose was to test which receptor in the inner ear is responsible for these reflexes. We compared masseter EMG responses induced in normal subjects (n= 9) by loud clicks (70–100 dB normal hearing level (NHL), 0.1 ms, 3 Hz) to those evoked in subjects with a selective lesion of the cochlea (n= 5), of the vestibule (n= 1) or with mixed cochlear‐vestibular failure (n= 5). In controls, 100 dB clicks induced bilaterally, in the unrectified mean EMG (unrEMG), a clear p11 wave followed by a less clear n15 wave and a subsequent n21 wave. Lowering the intensity to 70 dB clicks abolished the p11/n15 wave, while a p16 wave appeared. Rectified mean EMG (rectEMG) showed, at all intensities, an inhibitory deflection corresponding to the p16/n21 wave in the unrEMG. Compared to controls, all deaf subjects had a normal p11 wave, together with more prominent n15 wave; however, the p16/n21 waves, and their corresponding inhibition in the rectEMG, were absent. The vestibular patient had bilaterally clear p11 waves only when 100 dB clicks were delivered bilaterally or to the unaffected ear. Stimulation of the affected ear induced only p16/n21 waves. Data from mixed patients were consistent with those of deaf and vestibular patients. We conclude that click‐induced masseter p11/n15 waves are vestibular dependent, while p16/n21 waves depend on cochlear integrity.
Modulation of Ca2+ release and Ca2+ oscillations in HeLa cells and fibroblasts by mitochondrial Ca2+ uniporter stimulation
Authors: Vay Laura , Hernández‐SanMiguel Esther , Santo‐Domingo Jaime , Lobatón Carmen D. , Moreno Alfredo , Montero Mayte , Alvarez Javier
Published: January 2007

The recent availability of activators of the mitochondrial Ca2+ uniporter allows direct testing of the influence of mitochondrial Ca2+ uptake on the overall Ca2+ homeostasis of the cell. We show here that activation of mitochondrial Ca2+ uptake by 4,4′,4″‐(4‐propyl‐[1H]‐pyrazole‐1,3,5‐triyl)trisphenol (PPT) or kaempferol stimulates histamine‐induced Ca2+ release from the endoplasmic reticulum (ER) and that this effect is enhanced if the mitochondrial Na+–Ca2+ exchanger is simultaneously inhibited with CGP37157. This suggests that both Ca2+ uptake and release from mitochondria control the ability of local Ca2+ microdomains to produce feedback inhibition of inositol 1,4,5‐trisphosphate receptors (InsP3Rs). In addition, the ability of mitochondria to control Ca2+ release from the ER allows them to modulate cytosolic Ca2+ oscillations. In histamine stimulated HeLa cells and human fibroblasts, both PPT and kaempferol initially stimulated and later inhibited oscillations, although kaempferol usually induced a more prolonged period of stimulation. Both compounds were also able to induce the generation of Ca2+ oscillations in previously silent fibroblasts. Our data suggest that cytosolic Ca2+ oscillations are exquisitely sensitive to the rates of mitochondrial Ca2+ uptake and release, which precisely control the size of the local Ca2+ microdomains around InsP3Rs and thus the ability to produce feedback activation or inhibition of Ca2+ release.
Bioluminescence imaging of mitochondrial Ca2+ dynamics in soma and neurites of individual adult mouse sympathetic neurons
Authors: Núñez Lucía , Senovilla Laura , Sanz‐Blasco Sara , Chamero Pablo , Alonso María T. , Villalobos Carlos , García‐Sancho Javier
Published: January 2007

Changes in the cytosolic Ca2+ concentration ([Ca2+]c) are essential for triggering neurotransmitter release from presynaptic nerve terminals. Calcium‐induced Ca2+ release (CICR) from the endoplasmic reticulum (ER) may amplify the [Ca2+]c signals and facilitate neurotransmitter release in sympathetic neurons. In adrenal chromaffin cells, functional triads are formed by voltage‐operated Ca2+ channels (VOCCs), CICR sites and mitochondria. In fact, mitochondria take up most of the Ca2+ load entering the cells and are essential for shaping [Ca2+]c signals and exocytosis. Here we have investigated the existence of such functional triads in sympathetic neurons. The mitochondrial Ca2+ concentration ([Ca2+]m) in soma and neurites of individual mouse superior cervical ganglion (SCG) neurons was monitored by bioluminescence imaging of targeted aequorins. In soma, Ca2+ entry through VOCCs evoked rapid, near millimolar [Ca2+]m increases in a subpopulation of mitochondria containing about 40% of the aequorin. Caffeine evoked a similar [Ca2+]m increase in a mitochondrial pool containing about 30% of the aequorin and overlapping with the VOCC‐sensitive pool. These observations suggest the existence of functional triads similar to the ones described in chromaffin cells. In neurites, mitochondria were able to buffer [Ca2+]c increases resulting from activation of VOCCs but not those mediated by caffeine‐induced Ca2+ release from the ER. The weaker Ca2+ buffering by mitochondria in neurites could contribute to facilitate Ca2+‐induced exocytosis at the presynaptic sites.
Volitional control of neural activity: implications for brain–computer interfaces
Authors: Fetz Eberhard E.
Published: January 2007

Successful operation of brain–computer interfaces (BCI) and brain–machine interfaces (BMI) depends significantly on the degree to which neural activity can be volitionally controlled. This paper reviews evidence for such volitional control in a variety of neural signals, with particular emphasis on the activity of cortical neurons. Some evidence comes from conventional experiments that reveal volitional modulation in neural activity related to behaviours, including real and imagined movements, cognitive imagery and shifts of attention. More direct evidence comes from studies on operant conditioning of neural activity using biofeedback, and from BCI/BMI studies in which neural activity controls cursors or peripheral devices. Limits in the degree of accuracy of control in the latter studies can be attributed to several possible factors. Some of these factors, particularly limited practice time, can be addressed with long‐term implanted BCIs. Preliminary observations with implanted circuits implementing recurrent BCIs are summarized.
Is space expanding in the Friedmann universe models?
Authors: Grøn Øyvind , Elgarøy Øystein
Published: January 2007

The interpretation of the expanding universe as an expansion of space has recently been challenged. From the geodesic equation in Friedmann universe models and the empty Milne model, we argue that a Newtonian or special relativistic analysis is not applicable on large scales, and the general relativistic interpretation in terms of expanding space has the advantage of being globally consistent. We also show that the cosmic redshift, interpreted as an expansion effect, contains both the Doppler effect and the gravitational frequency shift.
On compressive radial tidal forces
Authors: Masi Marco
Published: January 2007

Radial tidal forces can be compressive instead of disruptive, a possibility that is frequently overlooked in high level physics courses. For example, radial tidal compression can emerge in extended stellar systems containing a smaller stellar cluster. For particular conditions the tidal field produced by this extended mass distribution can exert on the cluster it contains compressive effects instead of the common disruptive forces. This interesting aspect of gravity can be derived from standard relations given in many textbooks and introductory courses in astronomy and can serve as an opportunity to look closer at some aspects of gravitational physics, stellar dynamics, and differential geometry. The existence of compressive tides at the center of huge stellar systems might suggest new evolutionary scenarios for the formation of stars and primordial galactic formation processes.
Ion acoustic wave experiments in a high school plasma physics laboratory
Authors: Gekelman Walter , Wise J. , Pribyl P. , Baker R. , Layton W. , Skrzypek J. , Niknejadi P. , Ransom R. , Lee D. , Zarinshesnas R. , Kim T. , Buck R. , Warfel E. , Tasoff T. , Carmona J. , Skolnik S. , Kim L. , Furlong D. , Gibson N.
Published: January 2007

We describe a successful alliance between a university and several high schools. The alliance is centered on a laboratory experiment constructed by students and faculty. The experiment involves sophisticated concepts and equipment not readily available in high schools. Much of the experiment is directly related to the science and mathematics learned in high school, with opportunities to extend their understanding by applying it to a research experience. The experiment is in plasma physics, but a similar alliance can be implemented in any area of science. Although the number of high school students affected by any one alliance is small, the impact is potentially large in the scientific life of a participating student or teacher.
An introduction to dynamical friction in stellar systems
Authors: Aceves Héctor , Colosimo María
Published: January 2007

An introductory exposition of Chandrasekhar’s gravitational dynamical friction, appropriate for an undergraduate class in mechanics, is presented. This friction results when a heavy particle moving through a “sea” of much lighter star particles experiences a retarding force due to the exchange of energy and momentum. The general features of dynamical friction are presented, both in an elementary and in a more elaborate way using a hyperbolic two-body interaction. The orbital decay of a heavy particle in a homogeneous gravitational system is solved analytically, which leads to damped harmonic oscillator motion. Numerical integration of the equation of motion in a more realistic case is done. The results are compared to those of an N-body computer simulation. Several problems and projects are suggested for further study.
Porous layer impedance applied to a moving wall: Application to the radiation of a covered piston
Authors: Doutres Olivier , Dauchez Nicolas , Génevaux Jean-Michel
Published: January 2007

Modeling a porous layer mounted on a vibrating structure using acoustic impedance is investigated in this paper. It is shown that the use of surface impedance usually measured with the impedance tube method can provide an inaccurate estimation of the acoustic pressure radiated by the covered structure. The paper focuses on the derivation of an impedance, denoted the “transfer impedance,” which describes accurately the dynamic movement of the porous layer. Biot’s theory is used in the model to account for deformations in the thickness of the layer. Experimental validation is performed using a circular piston covered by a foam or a fibrous layer, radiating in an infinite half space. The radiation model including the transfer impedance shows close agreement with experimental data.
Survey of noise in coal preparation plants
Authors: Vipperman Jeffrey S. , Bauer Eric R. , Babich Daniel R.
Published: January 2007

In response to the continuing problem of noise induced hearing loss (NIHL) among mine workers, the National Institute for Occupational Safety and Health (NIOSH) has conducted numerous noise surveys in coal preparation plants. The research, consisting of worker dose monitoring, task observations, and equipment noise profiling, was completed in eight separate preparation plants. Worker dose monitoring was conducted for three shifts in most cases. Workers experiencing higher than allowable doses were task-observed for one full shift to correlate dose to noise source(s). Finally, noise levels on all floors, and in lunch rooms and control rooms, were characterized. Results indicate that only workers who routinely spend a significant portion of their shift in the plants (away from the control rooms) are susceptible to overexposure from noise. Certain pieces of equipment (screens, centrifuges, sieve bends) are the loudest primary noise sources responsible for the worker noise exposures.
Effect of duration on the frequency discrimination of individual partials in a complex tone and on the discrimination of fundamental frequency
Authors: Gockel Hedwig E. , Moore Brian C. J. , Carlyon Robert P. , Plack Christopher J.
Published: January 2007

Thresholds for the discrimination of fundamental frequency (F0DLs) and frequency difference limens (FDLs) for individual partials within a complex tone (F0=250Hz, harmonics 1–7) were measured for stimulus durations of 200, 50, and 16ms. The FDLs increased with decreasing duration. Although the results differed across subjects, the effect of duration generally decreased as the harmonic number increased from 1 to 4, then increased as the harmonic number increased to 6, and finally decreased for the seventh harmonic. For each duration, F0DLs were smaller than the smallest FDL for any individual harmonic, indicating that information is combined across harmonics in the discrimination of F0. F0DLs predicted from the FDLs corresponded well with observed F0DLs for the 200- and 16-ms durations but were significantly larger than observed F0DLs for the 50-ms duration. A supplementary pitch-matching experiment using two subjects indicated that the contribution of the seventh harmonic to the pitch of the 16-ms complex tone was smaller than would be predicted from the FDL for that harmonic. The results are consistent with the idea that the dominant region shifts upward with decreasing duration, but that the weight assigned to individual harmonics is not always adjusted in an optimal way.
Optimum speech level to minimize listening difficulty in public spaces
Authors: Kobayashi Masaaki , Morimoto Masayuki , Sato Hiroshi , Sato Hayato
Published: January 2007

For ideal speech communication in public spaces, it is important to determine the optimum speech level for various background noise levels. However, speech intelligibility scores, which is conventionally used as the subjective listening test to measure the quality of speech communication, is near perfect in most everyday situations. For this reason, it is proposed to determine optimum speech levels for speech communication in public spaces by using listening difficulty ratings. Two kinds of listening test were carried out in this work. The results of the tests and our previous work [M. Morimoto, H. Sato, and M. Kobayashi, J. Acoust. Soc. Am. 116, 1607–1613 (2004)] are jointly discussed for suggesting the relation between the optimum speech level and background noise level. The results demonstrate that: (1) optimum speech level is constant when background noise level is lower than 40dBA, (2) optimum speech level appears to be the level, which maintains around 15dBA of SN ratio when the background noise level is more than 40dBA, and (3) listening difficulty increases as speech level increases under the condition where SN ratio is good enough to keep intelligibility near perfect.
Linear and nonlinear measures of ocean acoustic environmental sensitivity
Authors: Dosso Stan E. , Giles Peter M. , Brooke Gary H. , McCammon Diana F. , Pecknold Sean , Hines Paul C.
Published: January 2007

This letter defines linear, linearized, and nonlinear measures of environmental sensitivity for ocean acoustic propagation that account for realistic uncertainties in various environmental parameters (water-column sound-speed profile and seabed geoacoustic properties). Simple interpretations of sensitivity are based on the implicit assumption of a linear relationship between parameter sensitivity and parameter uncertainty. This assumption is examined by comparing the three sensitivity measures over a range of parameter uncertainties about the actual assumed environmental uncertainty. Sensitivity range and depth dependencies are illustrated for realistic geoacoustic uncertainties and oceanographic variability of the sound-speed profile.
Measurement of the acoustic reflectivity of sirenia (Florida manatees) at 171kHz
Authors: Jaffe Jules S. , Simonet Fernando , Roberts Paul L. D. , Bowles Ann E.
Published: January 2007

The Florida manatee (Trichechus manatus latirostris) is an endangered sirenian. At present, its adult population (∼2200) seems stable, but tenuous. Manatee-boat collisions are a significant proportion (∼25%) of mortalities. Here, the potential use of active sonar for detecting manatees by quantifying sonic reflectivity is explored. In order to estimate reflectivity two methods were used. One method measured live reflections from captive animals using a carefully calibrated acoustic and co-registered optical system. The other method consisted of the analysis of animal tissue in order to obtain estimates of the sound speed and density and to predict reflectivity. The impedance measurement predicts that for a lateral view, the tissue reflectivity is close to 0.13, with a critical grazing angle of 28°. Data measured from live animals indicate that substantial reflections can be recorded, however in many instances observed “empirical target strengths” were less than an experimentally dependent −48-dB threshold. Conclusions favor the hypothesis that the animals reflect substantial amounts of sound; however, the reflections can often be specular, and therefore impractical for observation by a manatee detection sonar operating at 171kHz.
Generation of the vocal tract spectrum from the underlying articulatory mechanism
Authors: Kaburagi Tokihiko , Kim Jiji
Published: January 2007

A method for synthesizing vocal-tract spectra from phoneme sequences by mimicking the speech production process of humans is presented. The model consists of four main processes and is particularly characterized by an adaptive formation of articulatory movements. First, our model determines the time when each phoneme is articulated. Next, it generates articulatory constraints that must be met for the production of each phoneme, and then it generates trajectories of the articulatory movements that satisfy the constraints. Finally, the time sequence of spectra is estimated from the produced articulatory trajectories. The articulatory constraint of each phoneme does not change with the phonemic context, but the contextual variability of speech is reproduced because of the dynamic articulatory model. The accuracy of the synthesis model was evaluated using data collected by the simultaneous measurement of speech and articulatory movements. The accuracy of the phonemic timing estimates were measured and compared the synthesized results to the measured results. Experimental results showed that the model captured the contextual variability of both the articulatory movements and speech acoustics.
Evaluation of multichannel reproduced sound: Scaling auditory attributes underlying listener preference
Authors: Choisel Sylvain , Wickelmaier Florian
Published: January 2007

A study was conducted with the goal of quantifying auditory attributes that underlie listener preference for multichannel reproduced sound. Short musical excerpts were presented in mono, stereo, and several multichannel formats to a panel of 40 selected listeners. Scaling of auditory attributes, as well as overall preference, was based on consistency tests of binary paired-comparison judgments and on modeling the choice frequencies using probabilistic choice models. As a result, the preferences of nonexpert listeners could be measured reliably at a ratio scale level. Principal components derived from the quantified attributes predict overall preference well. The findings allow for some generalizations within musical program genres regarding the perception of and preference for certain spatial reproduction modes, but for limited generalizations across selections from different musical genres.