bluuebunny/crossref_metadata_2025 huggingface dataset:
The Malleable Meaning of Subjective Ease
Authors: Briñol Pablo , Petty Richard E. , Tormala Zakary L.
Published: February 2006

People can generate the same thoughts or process the same information with different degrees of ease, and this subjective experience has implications for attitudes and social judgment. In prior research, it has generally been assumed that the experience of ease or fluency is interpreted by people as something good. In the two experiments reported here, the meaning or value of ease was directly manipulated, and the implications for evaluative judgments were explored. Across experiments, we replicated the traditional ease-of-retrieval effect (more thought-congruent attitudes when thoughts were easy rather than difficult to generate) when ease was described as positive, but we reversed this effect when ease was described as negative. These findings suggest that it is important to consider both the content of metacognition (e.g., “those thoughts were easy to generate”) and the value associated with that content (e.g., “ease is good” or “ease is bad”).
When Questions Change Behavior
Authors: Levav Jonathan , Fitzsimons Gavan J.
Published: February 2006

In three experiments, we examined the meremeasurement effect, wherein simply asking people about their intent to engage in a certain behavior increases the probability of their subsequently engaging in that behavior. The experiments demonstrate that manipulations that should affect the ease of mentally representing or simulating the behavior in question influence the extent of the mere-measurement phenomenon. Participants who were asked about their intention to engage in various behaviors were more likely to engage in those behaviors than participants not asked about their intentions in situations in which mentally simulating the behavior in the intention question was relatively easy. We tested this ease-of-representation hypothesis using both socially desirable and socially undesirable behaviors, and our dependent variables comprised both self-reports and actual behaviors. Our findings have implications for survey research in various social contexts, including assessments of risky behaviors by public health organizations.
Message in a Ballad
Authors: Rentfrow Peter J. , Gosling Samuel D.
Published: February 2006

How is information about people conveyed through their preferences for certain kinds of music? Here we show that individuals use their music preferences to communicate information about their personalities to observers, and that observers can use such information to form impressions of others. Study 1 revealed that music was the most common topic in conversations among strangers given the task of getting acquainted. Why was talk about music so prevalent? Study 2 showed that (a) observers were able to form consensual and accurate impressions on the basis of targets' music preferences, (b) music preferences were related to targets' personalities, (c) the specific cues that observers used tended to be the ones that were valid, and (d) music preferences reveal information that is different from that obtained in other zero-acquaintance contexts. Discussion focuses on the mechanisms that may underlie the links between personality and music preferences.
Believing Is Seeing
Authors: Principe Gabrielle F. , Kanaya Tomoe , Ceci Stephen J. , Singh Mona
Published: February 2006

This study examined how an erroneous rumor circulated among preschoolers can influence their memory. One fourth of the children overheard a rumor from an adult conversation in which it was alleged that an event the children had not experienced themselves had occurred. A second fourth were the classmates of those who overheard the rumor. A third group had no exposure to the rumor. The remaining children actually experienced the event suggested by the rumor. One week later, the children were interviewed in either a neutral or a suggestive manner. Results from a second interview after a 2-week delay revealed that under both interview conditions, children who overheard the rumor, either from the adult conversation or during naturally occurring interactions with classmates, were as likely to report experiencing the rumored but nonexperienced event as were those who actually experienced it. Most reports of the rumored but nonexperienced event were in children's free recall and were accompanied by high levels of fictitious elaboration.
Test-Enhanced Learning
Authors: Roediger Henry L. , Karpicke Jeffrey D.
Published: February 2006

Taking a memory test not only assesses what one knows, but also enhances later retention, a phenomenon known as the testing effect. We studied this effect with educationally relevant materials and investigated whether testing facilitates learning only because tests offer an opportunity to restudy material. In two experiments, students studied prose passages and took one or three immediate free-recall tests, without feedback, or restudied the material the same number of times as the students who received tests. Students then took a final retention test 5 min, 2 days, or 1 week later. When the final test was given after 5 min, repeated studying improved recall relative to repeated testing. However, on the delayed tests, prior testing produced substantially greater retention than studying, even though repeated studying increased students' confidence in their ability to remember the material. Testing is a powerful means of improving learning, not just assessing it.
Stigma as Ego Depletion
Authors: Inzlicht Michael , McKay Linda , Aronson Joshua
Published: February 2006

This research examined whether stigma diminishes people's ability to control their behaviors. Because coping with stigma requires self-regulation, and self-regulation is a limited-capacity resource, we predicted that individuals belonging to stigmatized groups are less able to regulate their own behavior when they become conscious of their stigmatizing status or enter threatening environments. Study 1 uncovered a correlation between stigma sensitivity and self-regulation; the more Black college students were sensitive to prejudice, the less self-control they reported having. By experimentally activating stigma, Studies 2 and 3 provided causal evidence for stigma's ego-depleting qualities: When their stigma was activated, stigmatized participants (Black students and females) showed impaired self-control in two very different domains (attentional and physical self-regulation). These results suggest that (a) stigma is ego depleting and (b) coping with it can weaken the ability to control and regulate one's behaviors in domains unrelated to the stigma.
Team reflexivity in innovative projects
Authors: Hoegl Martin , Parboteeah K. Praveen
Published: February 2006

In this article, we provide a theoretical extension and empirical test of team reflexivity. Building on West's (1996) conceptual discussions of team reflexivity, we argue that in the context of teams with innovative projects (e.g. product development teams), team reflexivity will be positively related to team effectiveness and efficiency. Furthermore, we specify social skills and project management skills as important determinants of team reflexivity. Using data from 575 members, leaders, and team external managers referring to 145 software development teams, we find that team reflexivity is positively related to team effectiveness but not efficiency. Furthermore, both social skills and project management skills are positively related to team reflexivity. Theoretical and practical implications are discussed.
Universal decline in mortality in patients with advanced HIV‐1 disease in various demographic subpopulations after the introduction of HAART in Hong Kong, from 1993 to 2002
Authors: Chan KCW , Wong KH , Lee SS
Published: February 2006

Objective

Reductions in HIV/AIDS mortality associated with highly active antiretroviral therapy (HAART) have mainly been reported from Western countries. We studied the impact on survival of patients with advanced HIV disease after the introduction of HAART in Hong Kong.

Methods

The mortality pattern in a government clinic cohort of 511 adult HIV‐1‐infected patients with AIDS or CD4 count <200 cells/μL from 1993 to 2002 was examined. The number of deaths, the crude mortality rate (CMR) and the death rate per 1000 person‐months were recorded.

Results

Despite an increase in the patient population, 36 deaths occurred in the HAART era (1997–2002) as compared with 56 deaths in the pre‐HAART era (1993–1996). The overall annual CMR fell significantly from a high, fluctuating level of 10.8–30.4 per 100 mid‐year patient population pre‐HAART to a low, steady level of 0.8–6.9 per 100 mid‐year population in the HAART era (P=0.004, 1996 vs 1998; P<0.001, 1996 vs 2000; P<0.001, 1996 versus 2002). A fall in CMR was observed in all demographic subpopulations, categorized by sex, ethnicity, HIV exposure risk and age (P ranged from 0.012 to<0.001). Longitudinal tracking until mid‐2003 revealed a death rate of 9.2 events/1000 person‐months (52 deaths with 5661.5 person‐months follow up) among patients first diagnosed as having advanced disease during 1993–1996, and a lower death rate of 2.4 events/1000 person‐months (25 deaths with 10551.8 person‐months follow up) in patients first diagnosed as having advanced disease during 1997–2001 (rate ratio 3.9; 95% confidence interval 2.4–6.2).

Conclusion

There was dramatic temporal decline in mortality in patients with advanced HIV disease in all demographic subpopulations with the advent of HAART. Notwithstanding confounding variables, one reason for the universal decline may be that there was no major disparity in access to HIV care across community groups.
Effect of antiretroviral therapy on admissions of HIV‐infected patients to an intensive care unit
Authors: Palacios R , Hidalgo A , Reina C , de la Torre MV , Márquez M , Santos J
Published: February 2006

Objectives

To analyse the characteristics of HIV‐infected patients admitted to an Intensive Care Unit (ICU) and to compare them in the pre‐highly active antiretroviral therapy (HAART) and HAART eras.

Methods

All HIV‐infected patients who were admitted to the ICU of our hospital between January 1990 and December 2003 were reviewed. Patients were divided into two groups based on whether they were admitted before or after the advent of HAART, the cut‐off date being 31 December 1996.

Results

Data were collected on 66 patients, 17 in the pre‐HAART and 49 in the HAART era. The proportion of HIV‐infected patients admitted to the ICU in our HIV‐infected population increased after the introduction of HAART (3.8 vs 0.5%; P=0.001), and the largest diagnostic group was respiratory pathology in both periods. More than a third of patients were diagnosed with HIV infection during the ICU income, and only 31.2% were on antiretroviral therapy. The in‐hospital mortality was 53.0%, and later survival was high. There were no significant differences between the pre‐HAART and HAART eras.

Conclusions

Our results suggest that the characteristics of HIV‐infected patients admitted to ICU have not changed: respiratory diseases are still the most frequent cause of admission, in‐hospital mortality is high, and later survival rates are good.
Low initial trough plasma concentrations of lopinavir are associated with an impairment of virological response in an unselected cohort of HIV‐1‐infected patients
Authors: Wateba MI , Billaud E , Dailly E , Jolliet P , Raffi F
Published: February 2006

Objectives

The relationship between lopinavir trough plasma concentration at baseline and virological efficacy 3 months after the beginning of the therapy was investigated in an unselected cohort of HIV‐1‐infected patients

Methods

According to initial trough lopinavir plasma level, patients were classified into three groups: the subtherapeutic group (<3 mg/L, n=18), the therapeutic group (between 3 and 8 mg/L, n=50) and the toxic group (>8 mg/L, n=16). The virological response after 3 months of lopinavir treatment, defined as a viral load <200 HIV‐1 RNA copies/mL, was compared amongst these groups.

Results

The virological response was significantly different (P<0.05) between the subtherapeutic group (22.% of patients with viral load<200 copies/mL) and the other groups (56.0% of patients with a viral load<200 copies/mL in the therapeutic group and 56.2% in the toxic group).

Conclusions

A lower virological efficacy should be expected for experienced or naive patients with plasma trough lopinavir concentrations<3 mg/L at the beginning of treatment.
Determinants of discontinuation of initial highly active antiretroviral therapy regimens in a US HIV‐infected patient cohort*
Authors: Yuan Y , L'Italien G , Mukherjee J , Iloeje UH
Published: February 2006

Objectives

Optimization of initial highly active antiretroviral therapy (HAART) for complete viral suppression and better tolerability is paramount for the prognosis of HIV‐infected patients. Observational studies provide a better means than clinical trials of studying the determinants of discontinuation in actual practice.

Methods

A longitudinal cohort of US HIV‐positive patients who initiated HAART for the first time from 1996 to 2003 were included in the analysis. Stratified Cox proportional hazards models, considering time‐updated viral load and CD4 count data, were developed for analyzing time to first discontinuation.

Results

A total of 3414 antiretroviral‐naive HAART patients were identified. In a median follow‐up period of 211 days (mean 324 days), 628 patients (18.4%) reportedly discontinued the HAART regimen because of drug toxicity, 456 (13.4%) because of non‐compliance, and 257 (7.5%) because of treatment failure. In addition to the recorded reasons for discontinuation, black ethnicity [relative risk (RR) 1.28, 95% confidence interval (CI) 1.13–1.45], current smoking (RR 1.33, CI 1.18–1.50), high pill burden (RR 1.44, CI 1.22–1.70), and recent viral control (RR 0.63, CI 0.56–0.70) were all predictive of discontinuation. Only high pill burden (>15 pills/day), which is considered to be a surrogate for treatment regimen complexity, and the most recent poor viral control (HIV RNA) were found to be consistently associated with a higher likelihood of discontinuation.

Conclusions

Risk factors other than physician‐ or patient‐reported reasons play a role in discontinuation of initial HAART regimens. Identification of these risk factors and simplification of treatment regimens in those at high risk for discontinuation appear to be necessary in order to maximize the effectiveness of HAART regimens.
Incidence rate and risk factors for loss to follow‐up in a French clinical cohort of HIV‐infected patients from January 1985 to January 1998
Authors: Lebouché B , Yazdanpanah Y , Gérard Y , Sissoko D , Ajana F , Alcaraz I , Boitte P , Cadoré B , Mouton Y
Published: February 2006

Objectives

To determine the incidence rate and risk factors for loss to follow‐up (LFU) in HIV‐infected individuals.

Methods

We estimated the incidence rate of LFU in 1756 HIV‐infected patients enrolled in the Tourcoing Clinical Cohort from January 1985 to January 1998. We then investigated potential LFU risk factors at inclusion through a case–control study. Cases were 209 patients who had attended neither our clinic nor another HIV clinic for at least 1 year. Controls were 209 patients randomly selected from the group of HIV‐infected patients followed up regularly.

Results

The incidence of LFU was estimated at 4.3 per 100 person‐years [95% confidence interval (CI) 3.7–4.9]. Independent risk factors for LFU were (i) year of enrolment before 1993 [odds ratio (OR) 6.7; 95% CI 2.7–16.5 versus after 1997]; (ii) year of enrolment between 1993 and 1997 (OR 5.1; 95% CI 2.0–13.0 versus after 1997); (iii) age<30 years (OR 1.8; 95% CI 1.0–3.5 versus >40 years); (iv) injecting drug use (OR 5.3; 95% CI 2.7–10.5 versus men who have sex with men); (v) homelessness and/or illegal immigrant status (OR 2.2; 95% CI 1.0–4.9); and (vi) lack of a primary care provider (OR 6.0; 95% CI 2.4–15.1). A history of an AIDS‐defining illness (OR 0.3; 95% CI 0.2–0.6) and a history of psychiatric disease (OR 0.4; 95% CI 0.3–0.8) were both associated with a decreased risk of LFU.

Conclusions

This study assessed the sociodemographic, clinical and behavioural characteristics associated with LFU in HIV‐infected patients. The findings of this study may allow clinicians to identify patients at risk of LFU, so that appropriate interventions may be initiated.
Organizational identification: A conceptual and operational review
Authors: Edwards Martin R.
Published: February 2006

There is a growing body of literature presenting the argument that processes of organizational identification (OI) are extremely important in helping to ensure that staff work towards the interests of the organization. There are, however, a number of problems with the way that the notion of OI has been conceptualized and operationalized in the extant literature. This paper examines how OI has been defined and measured over a number of decades. A number of problems are identified with how OI has been conceptualized by researchers, including, for example, issues about whether there is an affective element to identification and how the construct relates to organizational commitment. The paper also includes a review of previous approaches to measuring the concept of OI and raises some key problems with existing research tools. The paper concludes by arguing for a particular conceptualization of OI which helps to clarify the complex relationship between identification and organizational commitment, while at the same time accommodating previous definitions of the construct.
External commercialization of knowledge: Review and research agenda
Authors: Lichtenthaler Ulrich
Published: February 2006

Companies increasingly make use of external knowledge exploitation, i.e. the commercialization of knowledge assets, although they often perceive considerable difficulties in managing external commercialization tasks. These difficulties are partly due to the imperfections in the markets for knowledge, which may be mastered by adequate management, as examples of various well‐known companies show. In combination, these facts point to the need for research into external knowledge exploitation. A thorough analysis of past research confirms this need and shows that the existing literature is highly fragmented. By integrating the main findings of the different research streams, a detailed overview of the literature on external knowledge exploitation is established. The key characteristics of externally leveraging knowledge assets are presented, and a research agenda is set up.
Of cats and Haruspices*: genetic intervention in the Florida panther. Response to Pimm et al. (2006)
Authors: Maehr D. S. , Crowley P. , Cox J. J. , Lacki M. J. , Larkin J. L. , Hoctor T. S. , Harris L. D. , Hall P. M.
Published: February 2006

The claim that the Florida panther Puma concolor coryi has been genetically rescued by the introduction of Texas cougars P. c. stanleyana is based on the questionable development and interpretation of a maximum likelihood model, data dredging and a misleading presentation of historical data. In addition, the claim that Florida panther ‘hybrids are expanding the known range of habitats panthers occupy and use’ is offered in the absence of data or supporting analyses. By (1) ignoring regional differences in habitat quality, (2) ignoring the earlier extinction of the hybrid Everglades population, (3) ignoring the influence of social structure on the relative success of Texas cougars and their offspring, (4) using cursory spatial analyses of panthers before and after intervention and (5) choosing a second‐best model, a misleading scenario was presented. Undoubtedly hybrid animals have increased in abundance and distribution on the south Florida landscape, but it is quite possible that current patterns of abundance and distribution would be similar if purebred Florida panthers had been introduced instead of Texas cougars in 1995. This is because all the demographic events that have occurred since genetic intervention in 1995 can be more reasonably explained by factors relating to panther social structure and habitat variability. We are hopeful that the current genetic management effort will contribute to the recovery of this endangered population; however, it is too early to claim that this intervention has succeeded or failed. We suggest a number of ways in which more reliable insight on this issue might be obtained.
Patients with chronic fatigue syndrome have reduced absolute cortical blood flow
Authors: Yoshiuchi Kazuhiro , Farkas Jeffrey , Natelson Benjamin H.
Published: February 2006

Prior studies on brain blood flow in chronic fatigue syndrome (CFS) did not find consistent results. This may be because they used single‐photon emission computed tomography to measure brain blood flow, which could not measure absolute blood flow. Therefore, the aim of this study was to test the hypothesis that patients with CFS have reduced absolute cerebral blood flow. Xenon‐computed tomography blood flow studies were done on 25 CFS patients and seven healthy controls. Analyses were done after stratifying the CFS patients based on the presence or absence of a current psychiatric disorder. Flow was diminished in both groups as follows: patients with no current psychiatric disorders had reduced cortical blood flow in the distribution of both right and left middle cerebral arteries (P<0·05 for both) while those with current psychiatric disorders had reduced blood flow only in the left middle cerebral artery territory (P<0·05). These data indicate that patients with CFS have reduced absolute cortical blood flow in rather broad areas when compared with data from healthy controls and that those devoid of psychopathology had the most reductions in cortical flow. These data support, in part, our earlier findings that patients devoid of psychopathology are the group most at risk of having some of the symptoms of CFS due to brain dysfunction.
Is ventilatory efficiency dependent on the speed of the exercise test protocol in healthy men and women?
Authors: Davis James A. , Sorrentino Kristin M. , Soriano April C. , Pham Patrick H. , Dorado Silvia
Published: February 2006

Indices of ventilatory efficiency have proven useful in assessing patients with heart and lung disease. One of these indices is the slope of the ventilation (V̇E) versus carbon dioxide output (V̇CO2) relationship during cardiopulmonary exercise testing (CPET) for work rates where the relationship is linear. However, this relationship is defined not only by the slope but also by the y‐intercept. To examine whether this relationship is dependent on the speed of the CPET protocol, 30 healthy subjects (16 males) were administered a rapid CPET with 1‐min increment duration (1‐min CPET) to the limit of tolerance and a slow CPET with 4‐min increment duration (4‐min CPET) to the lactate threshold. Ventilation and the gas fractions for oxygen and CO2 were measured with a Vacumed metabolic cart. The average increment size of both protocols for both sexes was not significantly different (P>0·05). For the males, the mean (SD) slope for the 1‐ and 4‐min CPET was 20·12 (2·61) and 20·37 (2·41), respectively. The corresponding values for the y‐intercept were 4.·89 (2·08) and 5.·10 (2·00) l min−1. For the females, the mean (SD) slope for the 1‐ and 4‐min CPET was 23·90 (2·38) and 24·16 (2·55), respectively. The corresponding values for the y‐intercept were 3·93 (0·39) and 3·77 (0·71) l min−1. Paired t‐test analysis demonstrated for both sexes that the slopes and y‐intercepts were not different for the two protocols (P>0·05). The results of this study demonstrate that the V̇E versus V̇CO2 relationship is not dependent on the speed of the CPET protocol.
Nocturnal autonomic nervous system activity impairment in sickle cell trait carriers
Authors: Connes Philippe , Martin Cyril , Barthelemy Jean‐Claude , Monchanin Géraldine , Atchou Guillaume , Forsuh Anthony , Massarelli Raphaël , Wouassi Dieudonné , Thiriet Patrice , Pichot Vincent
Published: February 2006

Sickle cell trait (SCT) is a genetic disease affecting the synthesis of normal haemoglobin (Hb) and marked by the heterozygous presence of HbA and HbS. Some studies have suggested that SCT carriers might be prone to vascular alterations, cardiac ischaemia and arrhythmias leading, in some subjects, to sudden death. It is well known that a loss or a disequilibrium of autonomic activity are powerful predictors of sudden cardiac death. We hypothesized that SCT subjects might exhibit alterations in the activity of the autonomic nervous system that could constitute further risk factors for cardiac complications. Resting haemorheological parameters (ηb, blood viscosity; ηp, plasma viscosity; Hct, haematocrit; Tk, red blood cell rigidity), and sympathetic and parasympathetic indices of nocturnal autonomic activity (temporal and frequency analysis of heart rate variability) were thus compared between a group of nine SCT subjects and a group of nine control subjects. ηb was higher in the SCT group than in the control group while Hct, ηp and Tk were not different. Global variability (SDNN, SDNNIDX) and parasympathetic (PNN50, RMSSD, HF) indices were significantly lower in the SCT group compared with the control group, while the LF/HF ratio was highly increased, underlining a major sympathetic shift. The autonomic imbalance in SCT subjects was mainly related to lowered parasympathetic activity. Thus, our study suggests an additional global decrease and imbalance of autonomic nervous system activity to biological disorders of SCT carriers, that may constitute further risk factors for cardiac complications in this population.
Arterial blood flow and autonomic function in full‐term infants
Authors: Gabai Nili , Cohen Ayala , Mahagney Ayed , Bader David , Tirosh Emanuel
Published: February 2006

Objectives:  To investigate variations in the autonomic functions and blood‐flow velocity of the arteries supplying to the brainstem in supine and prone positions.

Methods:  Forty‐one full‐term infants were studied at the age of 24–72 h. Each infant underwent respiratory, cardiac and eye movement analyses in supine and prone positions. In addition, blood‐flow velocity of the basilar and vertebral arteries was measured with a 2 MHz probe for 5 min in each position. Two time domain measures of heart rate variability (HRV) (Standard deviation of normal R–R intervals for long‐term and pNN50 for short‐term variability) were employed.

Results:  Significantly decreased short‐ (P<0·001) and long (P = 0·003)‐term variabilities were observed in prone when compared with supine position. Increased short‐term variability in active sleep with no interaction with position was observed (P = 0·005). A significant decreased mean (P = 0·001) and peak (P = 0·001–0·003) blood‐flow velocity in prone when compared with supine position were measured in all three arteries supplying to the brainstem. No significant correlation between HRV and arterial blood‐flow velocity (ABFV) was observed in either position.

Comment:  The results of the present study in agreement with previous studies reflect the vulnerability of infants in prone position as related to brainstem function. However, it appears that ABFV and autonomic functions as reflected by HRV are independent physiological measures, possibly indicating regulation autonomy of the central nervous system.
Forelimb postischaemic reactive hyperaemia is impaired by hypotensive low body negative pressure in healthy subjects
Authors: Charles Marc , Pichot Vincent , Barthelemy Jean‐Claude , Roche Frederic , Costes Frederic
Published: February 2006

Local metabolic conditions adapt blood supply to metabolic requirement by a direct effect on vascular smooth muscles and indirectly by modulating sympathetic vasoconstrictor effectiveness. During exercise, sympathetic nervous activity could in turn interfere on local metabolic control of vascular tone and restrain blood flow to active muscles. In order to investigate that interaction non‐invasively, we measured postischaemic reactive hyperaemia (RH) in the forelimb of eight healthy young men (22·7 ± 2·1 years) at rest and during two levels of sympathetic stimulation using low body negative pressure (LBNP −15 and −30 mmHg). During every stages, RH was measured after 40, 60, 90 and 180 s of arterial occlusion, respectively. In control conditions, RH rose with duration of ischaemia (18·9, 24·2, 30·4, 33·1 ml min−1 per 100 ml−1 for 40, 60, 90 and 180 s of ischaemia, respectively). During non‐hypotensive LBNP (−15 mmHg) sympathetic activation was associated with decreased forelimb blood flow (6·4 ± 0·9 versus 3·9 ± 0·6 ml min−1 per 100 ml−1, P<0·01), but RH were not significantly different from control conditions. During hypotensive tachycardia LBNP (−30 mmHg), RH were significantly lower than under the previous LBNP stage. This fall in RH was greater after the shortest gap of ischaemia and tapered off as arterial occlusion gap increased (−22·3, −13·1, −10·5 and −8·7% for 40, 60, 90 and 180 s of ischaemia, respectively). These results suggested that vascular tone adaptation to local metabolic conditions was modified by sympathetic nervous activation. This was particularly marked when an hypotensive‐mediated sympathetic stimulation was opposed to short gaps of ischaemia.
The relative severity of acts of physical violence in heterosexual relationships: An item response theory analysis
Authors: REGAN KATHERINE V. , BARTHOLOMEW KIM , KWONG MARILYN J. , TRINKE SHANNA J. , HENDERSON ANTONIA J. Z.
Published: February 2006

This study evaluated the structure of an expanded version of the physical violence scale of the Conflict Tactics Scales (CTS). A community sample of 1,092 randomly selected men and women reported on perpetration and receipt of 14 violent acts in their relationships. Item response theory analyses indicated that the violence items were unidimensional for recipient and perpetrator reports of men's and women's violence. There was convergence between severity of acts as reported by perpetrators and recipients for both men's and women's violence. Results indicated that adding together the number of different acts endorsed to form a total score is appropriate for both men's and women's violence. Total scores were strongly related to likelihood of injury, supporting the validity of CTS‐type measures to assess severity of violence.
Costs and satisfaction in close relationships: The role of loss–gain framing
Authors: BERGER ANDREA R. , JANOFF‐BULMAN RONNIE
Published: February 2006

Two studies were conducted to clarify the pattern of mixed results found in past research regarding the association between costs and satisfaction in close relationships. Insights from Prospect Theory (D. Kahneman & A. Tversky, 1979, 2000) suggested the importance of gain–loss framing in understanding costs. When costs are attached to valued outcomes, they are perceived as gains or investments; otherwise they are perceived as losses. Appreciation by one's partner for communal behaviors and family chores provided the basis for exploring costs as gains versus losses. We hypothesized that when costs were appreciated, the greater the costs, the greater the relationship satisfaction; whereas when they were not appreciated, the greater the costs, the lower the relationship satisfaction. Further, we expected appreciation to be associated with perceived motives for incurring the costs: positively with “want” perceptions and negatively with “should” perceptions. These hypotheses were supported in research with both dating couples and women in long‐term marital or cohabiting relationships and using two types of communal behaviors: Partner Favors and more tedious Family Chores. In general, the greater the number of communal behaviors and family chores, the greater the relationship satisfaction when appreciated; the greater the number, the lower the satisfaction when relatively unappreciated.
Let's be friends: Relational self‐construal and the development of intimacy
Authors: GORE JONATHAN S. , CROSS SUSAN E. , MORRIS MICHAEL L.
Published: February 2006

Two studies examined the role of relational self‐construal in the development and maintenance of intimacy in roommate relationships. In Study 1, 98 roommate pairs completed questionnaires assessing attitudes toward their relationship. Results showed that high relationals disclosed more personal information than lows, which was then associated with their roommates’ perceptions of relationship quality. In Study 2, 142 roommate pairs followed the Study 1 procedure with a 1‐month follow‐up session for the participants (86% returned). Results replicated the findings of Study 1 and showed reciprocated disclosure from the roommates, followed by increased disclosure by the participants at Time 2. These findings support the H. T. Reis and P. Shaver (1988) intimacy model and indicate the importance of the self‐construal in this interpersonal process.
The costs and benefits of practical and emotional support on adjustment: A daily diary study of couples experiencing acute stress
Authors: SHROUT PATRICK E. , HERMAN CRAIG M. , BOLGER NIALL
Published: February 2006

Emotional support from intimate partners has been shown to have both costs and benefits for daily anxious and depressed moods (N. Bolger, A. Zuckerman, & R. C. Kessler, 2000). We examine whether similar costs and benefits are found for practical support, and when fatigue, vigor, and anger are outcomes. Results are based on daily diary reports from 68 recent law school graduates and their intimate partners during the month before the New York State bar examination. Partners’ reports of practical support provision to the examinee were beneficial in that they were associated with decreased examinee fatigue and increased examinee vigor. In contrast, examinees’ recognition of emotional support receipt was costly in that it was associated with increases in anger, as well as anxious and depressed mood. Results highlight the distinction between emotional and practical support and are consistent with findings that suggest that invisible (provided but not recognized) support leads to the best outcomes.
Resolving Critical Habitat Designation Failures: Reconciling Law, Policy, and Biology
Authors: HAGEN AMY N. , HODGES KAREN E.
Published: February 2006

Abstract:  The U.S. Endangered Species Act (ESA) requires designation of critical habitat concurrent with species listing. The U.S. Fish and Wildlife Service often has not designated critical habitat, based on the legal exceptions in the ESA of “not prudent” or “not determinable.” This lack of habitat designation has led to numerous lawsuits and court orders to designate critical habitat for listed species. Court‐mediated implementation of critical habitat is costly and delays listing for at‐risk species. Legal, policy, judicial, and biological issues all contribute to the current inability of the law as enforced to lead to timely and cost‐effective critical habitat designation. Although increased appropriations and delaying critical habitat designation until recovery planning have been proposed as solutions, we find that it will be essential to change the critical‐habitat guidelines to a decision‐analysis framework to make critical habitat scientifically and legally workable as a conservation tool.
Effects of the Surrounding Matrix on Tree Recruitment in Amazonian Forest Fragments
Authors: NASCIMENTO HENRIQUE E. M. , ANDRADE ANA C. S. , CAMARGO JOSÉ LUÍS C. , LAURANCE WILLIAM F. , LAURANCE SUSAN G. , RIBEIRO JOSÉ EDUARDO L.
Published: February 2006

Abstract:  Little is known about how the surrounding modified matrix affects tree recruitment in fragmented forests. We contrasted effects of two different matrix types, Vismia‐ and Cecropia‐dominated regrowth, on recruitment of pioneer tree species in forest fragments in central Amazonia. Our analyses were based on 22, 1‐ha plots in seven experimental forest fragments ranging in size from 1 to 100 ha. By 13 to 17 years after fragmentation, the population density of pioneer trees was significantly higher in plots surrounded by Vismia regrowth than in plots surrounded by Cecropia regrowth, and the species composition and dominance of pioneers differed markedly between the two matrix types. Cecropia sciadophylla was the most abundant pioneer in fragments surrounded by Cecropia regrowth (constituting nearly 50% of all pioneer trees), whereas densities of species in Vismia‐surrounded fragments were distributed more evenly. Thus the surrounding matrix had a strong influence on patterns of tree recruitment in Amazonian forest fragments.
Global Warming and Extinctions of Endemic Species from Biodiversity Hotspots
Authors: MALCOLM JAY R. , LIU CANRAN , NEILSON RONALD P. , HANSEN LARA , HANNAH LEE
Published: February 2006

Abstract:  Global warming is a key threat to biodiversity, but few researchers have assessed the magnitude of this threat at the global scale. We used major vegetation types (biomes) as proxies for natural habitats and, based on projected future biome distributions under doubled‐CO2 climates, calculated changes in habitat areas and associated extinctions of endemic plant and vertebrate species in biodiversity hotspots. Because of numerous uncertainties in this approach, we undertook a sensitivity analysis of multiple factors that included (1) two global vegetation models, (2) different numbers of biome classes in our biome classification schemes, (3) different assumptions about whether species distributions were biome specific or not, and (4) different migration capabilities. Extinctions were calculated using both species‐area and endemic‐area relationships. In addition, average required migration rates were calculated for each hotspot assuming a doubled‐CO2 climate in 100 years. Projected percent extinctions ranged from <1 to 43% of the endemic biota (average 11.6%), with biome specificity having the greatest influence on the estimates, followed by the global vegetation model and then by migration and biome classification assumptions. Bootstrap comparisons indicated that effects on hotpots as a group were not significantly different from effects on random same‐biome collections of grid cells with respect to biome change or migration rates; in some scenarios, however, hotspots exhibited relatively high biome change and low migration rates. Especially vulnerable hotspots were the Cape Floristic Region, Caribbean, Indo‐Burma, Mediterranean Basin, Southwest Australia, and Tropical Andes, where plant extinctions per hotspot sometimes exceeded 2000 species. Under the assumption that projected habitat changes were attained in 100 years, estimated global‐warming‐induced rates of species extinctions in tropical hotspots in some cases exceeded those due to deforestation, supporting suggestions that global warming is one of the most serious threats to the planet's biodiversity.
The amphioxus T‐box gene,AmphiTbx15/18/22, illuminates the origins of chordate segmentation
Authors: Beaster‐Jones Laura , Horton Amy C. , Gibson‐Brown Jeremy J. , Holland Nicholas D. , Holland Linda Z.
Published: February 2006

SUMMARYAmphioxus and vertebrates are the only deuterostomes to exhibit unequivocal somitic segmentation. The relative simplicity of the amphioxus genome makes it a favorable organism for elucidating the basic genetic network required for chordate somite development. Here we describe the developmental expression of the somite marker,AmphiTbx15/18/22, which is first expressed at the mid‐gastrula stage in dorsolateral mesendoderm. At the early neurula stage, expression is detected in the first three pairs of developing somites. By the mid‐neurula stage, expression is downregulated in anterior somites, and only detected in the penultimate somite primordia. In early larvae, the gene is expressed in nascent somites before they pinch off from the posterior archenteron (tail bud). Integrating functional, phylogenetic and expression data from a variety of triploblast organisms, we have reconstructed the evolutionary history of theTbx15/18/22subfamily. This analysis suggests that theTbx15/18/22gene may have played a role in patterning somites in the last common ancestor of all chordates, a role that was later conserved by its descendents following gene duplications within the vertebrate lineage. Furthermore, the comparison of expression domains within this gene subfamily reveals similarities in the genetic bases of trunk and cranial mesoderm segmentation. This lends support to the hypothesis that the vertebrate head evolved from an ancestor possessing segmented cranial mesoderm.
Expression of Dlx genes during the development of the zebrafish pharyngeal dentition: evolutionary implications
Authors: Borday‐Birraux V. , Van der Heyden C. , Debiais‐Thibaud M. , Verreijdt L. , Stock D. W. , Huysseune A. , Sire J.‐Y.
Published: February 2006

SUMMARY
In order to investigate similarities and differences in genetic control of development among teeth within and between species, we determined the expression pattern of all eight Dlx genes of the zebrafish during development of the pharyngeal dentition and compared these data with that reported for mouse molar tooth development. We found that (i) dlx1a and dlx6a are not expressed in teeth, in contrast to their murine orthologs, Dlx1 and Dlx6; (ii) the expression of the six other zebrafish Dlx genes overlaps in time and space, particularly during early morphogenesis; (iii) teeth in different locations and generations within the zebrafish dentition differ in the number of genes expressed; (iv) expression similarities and differences between zebrafish Dlx genes do not clearly follow phylogenetic and linkage relationships; and (v) similarities and differences exist in the expression of zebrafish and mouse Dlx orthologs. Taken together, these results indicate that the Dlx gene family, despite having been involved in vertebrate tooth development for over 400 million years, has undergone extensive diversification of expression of individual genes both within and between dentitions. The latter type of difference may reflect the highly specialized dentition of the mouse relative to that of the zebrafish, and/or genome duplication in the zebrafish lineage facilitating a redistribution of Dlx gene function during odontogenesis.
Stage‐ and tissue‐specific patterns of cell division in embryonic and larval tissues of amphioxus during normal development
Authors: Holland Nicholas D. , Holland Linda Z.
Published: February 2006

SUMMARY
The distribution of dividing cells is described for embryos and larvae of amphioxus (Branchiostoma floridae) pulse labeled with bromodeoxyuridine. Because cell division is assessed for all of the developing tissues, this is the first comprehensive study of developmental cell proliferation for an animal lacking a stereotyped cell lineage. In amphioxus, cell divisions are virtually synchronous during cleavage, but become asynchronous at the blastula stage. Starting at the neurula stage, after the origin of the mesoderm, the proportion of dividing cells progressively declines in the somitic mesoderm and notochord. Other tissues, however, deviate from this pattern. For example, in the mid‐neurula, there is a brief, intense burst of mitosis at the anterior end of the neural plate. Also, from the neurula through the early larval stage, all of the ectoderm cells cease dividing and develop cilia that propel the animal through the water; subsequently, in the epidermis of later larvae, mitosis resumes and the proportion of ciliated cells declines as muscular undulation gradually replaces ciliation for swimming. Finally, in the early larvae, there is a terminal arrest of cell division in three cell types that differentiate early to participate in feeding as soon as the mouth opens—namely the ciliated pharyngeal cells that produce the feeding current and the secretory cells of the club‐shaped gland and endostyle that export food‐trapping mucus into the pharynx. In sum, these stage‐ and tissue‐specific changes in cell proliferation intensity illustrate how the requirements of embryonic and larval natural history can shape developmental programs.
Developmental expression of transcription factor genes in a demosponge: insights into the origin of metazoan multicellularity
Authors: Larroux Claire , Fahey Bryony , Liubicich Danielle , Hinman Veronica F. , Gauthier Marie , Gongora Milena , Green Kathryn , Wörheide Gert , Leys Sally P. , Degnan Bernard M.
Published: February 2006

SUMMARYDemosponges are considered part of the most basal evolutionary lineage in the animal kingdom. Although the sponge body plan fundamentally differs from that of other metazoans, their development includes many of the hallmarks of bilaterian and eumetazoan embryogenesis, namely fertilization followed by a period of cell division yielding distinct cell populations, which through a gastrulation‐like process become allocated into different cell layers and patterned within these layers. These observations suggest that the last common ancestor (LCA) to all living animals was developmentally more sophisticated than is widely appreciated and used asymmetric cell division and morphogen gradients to establish localized populations of specified cells within the embryo. Here we demonstrate that members of a range of transcription factor gene classes, many of which appear to be metazoan‐specific, are expressed during the development of the demospongeReniera, including ANTP,Pax,POU,LIM‐HD,Sox,nuclear receptor,Fox(forkhead),T‐box,Mef2, andEtsgenes. Phylogenetic analysis of these genes suggests that not only the origin but the diversification of some of the major developmental metazoan transcription factor classes took place before sponges diverged from the rest of the Metazoa. Their expression during demosponge development suggests that, as in today's sophisticated metazoans, these genes may have functioned in the regulatory network of the metazoan LCA to control cell specification and regionalized gene expression during embryogenesis.
Head size constrains forebrain development and evolution in ray‐finned fishes
Authors: Striedter Georg F. , Northcutt R. Glenn
Published: February 2006

SUMMARYIn ray‐finned fishes, which comprise nearly half of all vertebrate species, the telencephalon does not evaginate, as it does in other vertebrates, but instead everts. No detailed explanation for this species difference has ever been offered. Here we propose that telencephalic eversion evolved because ray‐finned fish embryos are so small that their telencephalon cannot evaginate but must, instead, squeeze into the space just dorsal to the developing nasal epithelia and rostral to the eyes—morphogenetic movements that amount to eversion. Evidence for this hypothesis derives from cladistic analyses, which show that early ray‐finned fishes reduced their adult body size and adopted a novel reproductive strategy, based on the production of myriad minute young. Because body size tends to be inversely proportional to brain:body ratio, this phylogenetic reduction in body size implies that embryonic ray‐finned fishes should have proportionately larger brains than embryos of species whose telencephalons evaginate. This prediction was confirmed by comparing serially sectioned heads of representative ray‐finned and cartilaginous fish embryos at several stages of development. The brain, excluding its ventricles, occupies 36–46% of the cranial cavity in embryonic ray‐finned fishes, but less than 20% in embryonic sharks. Moreover, three‐dimensional reconstructions show that in embryonic ray‐finned fishes the telencephalon has no room for a full‐fledged evagination; instead, it spreads into the spaces just dorsal and caudal to the developing nasal epithelia. These morphogenetic movements, in conjunction with a thinning of the forebrain roof, generate telencephalic eversion.