bluuebunny/crossref_metadata_2025 huggingface dataset:
Superoxide During Reperfusion Contributes to Caspase-8 Expression and Apoptosis After Transient Focal Stroke
Authors: Morita-Fujimura Yuiko , Fujimura Miki , Yoshimoto Takashi , Chan Pak H.
Published: October 2007

Background and Purpose

—

Reactive oxygen species produced during reperfusion may play a detrimental role in focal cerebral ischemia (FCI). We examined the protein expression of caspase-8, which plays a major role in both Fas-dependent and cytochrome c–dependent apoptotic pathways after FCI with or without reperfusion. Caspase-8 expression after transient FCI was compared between wild-type and transgenic mice that overexpress the cytosolic antioxidant copper/zinc superoxide dismutase (SOD1).

Methods

—

Adult male CD-1 mice were subjected to 1 hour of FCI and reperfusion or to permanent FCI by intraluminal blockade of the middle cerebral artery. DNA fragmentation was evaluated by genomic DNA gel electrophoresis. Caspase-8 expression was analyzed by Western blot.

Results

—

Caspase-8 was significantly induced 4 hours after transient FCI and remained at an increased level until 24 hours, whereas it was not modified after permanent FCI. Genomic DNA gel electrophoresis showed DNA laddering in a pattern similar to that seen in apoptosis, with a small amount of background smear 24 hours after transient FCI, whereas 25 hours of permanent FCI resulted in less DNA laddering with a strong background smear. Caspase-8 induction was significantly reduced in SOD1 transgenic mice compared with wild-type mice 4 hours after transient FCI.

Conclusions

—

The results suggest that increased reactive oxygen species production during reperfusion may contribute to the induction of caspase-8, thereby exacerbating apoptosis after FCI.
Basilar and Middle Cerebral Artery Reserve
Authors: Barrett Kevin M. , Ackerman Robert H. , Gahn Georg , Romero Javier M. , Candia Morelia
Published: October 2007

Background and Purpose

—

A 1997 report suggests that the posterior circulation of the normal brain has diminished vasoreactivity compared with the anterior circulation. To further study this, we quantified and compared the vasodilatory capacities of the middle cerebral (MCA) and basilar artery (BA) territories in response to changes in Pa
co
2
, as indices of respective cerebrovascular reserve (CVR). If posterior circulation CVR is indeed physiologically lower than that of the MCA, it might indicate a greater risk of low-flow ischemia distal to basilar obstructive cerebrovascular lesions and provide a rationale for earlier treatment of such lesions with interventional techniques. We also wished to establish normal baseline CVR values for the posterior circulation.

Methods

—

Twelve patients with signs and/or symptoms suggestive of posterior circulation disease but without flow-limiting obstructive changes and 11 normal controls were entered into the study. With the use of transcranial Doppler techniques, alterations in blood flow velocity in response to sequential breath-holding trials of varying duration were simultaneously monitored in both MCAs and the BA. CVR was measured as the percent velocity increase (during breath-holding) from resting baseline values.

Results

—

No significant differences were found in CVR between the MCA and BA territories in or between patients and controls.

Conclusions

—

Our study suggests that the anterior and posterior circulations have similar reserve capacities in individuals without flow-limiting cerebrovascular obstructive lesions and that the BA territory, relative to the MCA territory, is not at increased risk for low-flow stroke on the basis of limited reserve potential.
Effect of Prior Aspirin Use on Stroke Severity in the Trial of Org 10172 in Acute Stroke Treatment (TOAST)
Authors: Wilterdink Janet L. , Bendixen Birgitte , Adams Harold P. , Woolson Robert F. , Clarke William R. , Hansen Michael D.
Published: October 2007

Background and Purpose

—

Although the efficacy of aspirin in reducing stroke incidence is clear, its role in reducing stroke severity is disputed. This study compares stroke severity between patients who did or did not take aspirin in the week before stroke and enrollment in the Trial of Org 10172 in Acute Stroke Treatment (TOAST).

Methods

—

Of 1275 patients randomized, 509 reported aspirin use in the week before stroke; 766 did not. Clinical stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS) and the Supplementary Motor Examination (SME) at trial entry and at 3 months. Using these scales, we compared the categorization of stroke severity (mild, moderate, and severe) and mean scores between aspirin users and nonusers.

Results

—

The difference in distribution of baseline NIHSS scores was statistically significant between aspirin users and nonusers (
P
=0.006), with a greater percentage of milder strokes among aspirin users. The difference in mean baseline NIHSS scores was also significantly lower in aspirin users (8.2) and nonusers (9.3) (
P
=0.003). The distribution of baseline SME scores and mean SME scores also showed lower stroke severity in aspirin users than in nonusers (
P
=0.048 and
P
=0.004, respectively). At 3 months, differences in stroke severity measured by the SME but not the NIHSS remained statistically significant. Seven-day and 3-month mortality did not differ significantly.

Conclusions

—

In this study aspirin use is associated with milder clinical deficits at stroke onset. These deficits may affect prognosis and influence response to treatment. Future clinical trials should ensure that prestroke aspirin use is comparable in study groups.
Sphingosine 1-Phosphate Contracts Canine Basilar Arteries In Vitro and In Vivo
Authors: Tosaka Masahiko , Okajima Fumikazu , Hashiba Yasuhiro , Saito Nobuhito , Nagano Takuro , Watanabe Takashi , Kimura Takao , Sasaki Tomio
Published: October 2007

Background and Purpose

—

Sphingosine 1-phosphate (S1P) is a platelet-derived bioactive lipid that exerts a variety of biological responses, including vasocontraction. To understand the involvement of S1P in cerebral vasospasm, we investigated the effect of S1P on vasocontraction of the canine basilar artery in vitro and in vivo.

Methods

—

We recorded isometric tension in basilar arterial rings from dogs in vitro and estimated time-course changes in the diameter of canine basilar arteries and the S1P concentration in cerebrospinal fluid (CSF) by angiography and radioreceptor assays, respectively, after administering S1P into the cisterna magna. Changes in the supernatant S1P concentration during clot formation were monitored by using the in vitro subarachnoid hemorrhage model, in which blood is mixed with CSF.

Results

—

At concentrations ranging between 100 nmol/L and 10 μmol/L, S1P induced a dose-dependent contraction of the basilar artery in vitro. This effect was significantly inhibited by Y-27632, a highly selective Rho-kinase inhibitor. The administration of S1P into the CSF induced a 60% to 70% decrease in the arterial diameter within 15 minutes, and vasocontraction continued for 2 days thereafter. The concentration of S1P in the supernatant during clot formation in vitro reached ≈300 nmol/L.

Conclusions

—

S1P induces vasocontraction in the canine basilar artery in vitro and in vivo, possibly through a mechanism involving activation of the Rho/Rho-kinase pathway. Thus, S1P might be considered as a novel spasmogenic substance involved in cerebral vasospasm after subarachnoid hemorrhage.
Cerebrovascular Events in Patients With Significant Stenosis of the Carotid Artery Are Associated With Hyperhomocysteinemia and Platelet Antigen-1 (Leu33Pro) Polymorphism
Authors: Streifler J.Y. , Rosenberg N. , Chetrit A. , Eskaraev R. , Sela B.A. , Dardik R. , Zivelin A. , Ravid B. , Davidson J. , Seligsohn U. , Inbal A.
Published: October 2007

Background and Purpose

—

Although risk factors for carotid artery stenosis caused by atherosclerosis are known, it is unclear what triggers “activation” of the atherosclerotic plaques and the ensuing thromboembolic cerebral events. The aim of this study was to evaluate whether thrombophilic factors, platelet glycoprotein (GP) polymorphisms, and homocysteine are associated with a risk of ischemic events in patients with significant carotid stenosis.

Methods

—

Consecutive patients with ≥50% carotid stenosis, whether symptomatic (with ipsilateral ischemic events) or asymptomatic, who were evaluated and followed in a neurovascular clinic were tested for plasma levels of homocysteine, C677T mutation in methylenetetrahydrofolate reductase, G20210A mutation of factor II, factor V Leiden, antiphospholipid antibodies, and polymorphisms of platelet membrane GP: human platelet antigen (HPA)-1, GP Ia (C807T), and GP Ib (variable number of tandem repeats, Kozak, and HPA-2).

Results

—

Eighty-six asymptomatic and 67 symptomatic patients were evaluated. The former group was older (73.7±6.9 versus 69.5±9.1 years,
P
=0.02). Major risk factors for stroke were similar in both groups. In symptomatic patients versus asymptomatic patients, hyperhomocysteinemia was 3-fold more frequent (34.3% versus 12.8%, respectively;
P
=0.002) and HPA-1a/b was almost 2-fold more common (38.8% versus 20.9%, respectively;
P
=0.01). All other thrombophilic factors and platelet polymorphisms studied did not differ significantly between the 2 groups. Multivariate analysis revealed that hyperhomocysteinemia and the HPA-1a/b genotype conferred a significant risk of cerebral ischemic events, with odds ratios (95% CI) of 4.07 (1.7 to 9.7) and 3.4 (1.5 to 7.8), respectively.

Conclusions

—

Hyperhomocysteinemia and HPA-1a/b are independent risk factors for ischemic events in patients with significant carotid stenosis.
Pravastatin Improves Cerebral Vasomotor Reactivity in Patients With Subcortical Small-Vessel Disease
Authors: Sterzer Philipp , Meintzschel Frank , Rösler Alexander , Lanfermann Heinrich , Steinmetz Helmuth , Sitzer Matthias
Published: October 2007

Background and Purpose

—

Recent investigations have suggested an important role of statins in the prevention of stroke and dementia independent of their lipid-lowering properties. Using transcranial Doppler sonography (TCD), we examined acetazolamide reactivity as a marker of cerebral vasoreactivity in patients with subcortical small-vessel disease before and after pravastatin treatment.

Methods

—

In 16 patients (mean age 68±10 years) with subcortical small-vessel disease, cerebral vasomotor reactivity was tested using TCD insonating the middle cerebral artery. Cerebral blood flow velocity (CBFV) increase after bolus injection of 1 g acetazolamide was determined before and after 2-month treatment with pravastatin sodium 20 mg daily.

Results

—

Relative CBFV increase was significantly greater after pravastatin treatment (41.9±23.7% versus 55.7±18.3%,
P
=0.004). Comparison of CBFV at rest before and after treatment with pravastatin did not show significant differences. There was a strong negative correlation between the pravastatin-induced enhancement of vasomotor reactivity and the pretreatment CBFV increase (β=−0.64,
P
=0.019). No associations were found between the effect of pravastatin on vasomotor reactivity and pretreatment levels or changes of LDL cholesterol.

Conclusions

—

This pilot study provides the first evidence for a significant improvement of cerebral vasomotor reactivity by statin therapy in patients with cerebral small-vessel disease. The results may help to elucidate the preventive effect of statins and provide insights into the pathophysiology of cerebral small-vessel disease.
Automatic Classification of HITS Into Artifacts or Solid or Gaseous Emboli by a Wavelet Representation Combined With Dual-Gate TCD
Authors: Devuyst G. , Darbellay G.A. , Vesin J.-M. , Kemény V. , Ritter M. , Droste D.W. , Molina C. , Serena J. , Sztajzel R. , Ruchat P. , Lucchesi C. , Dietler G. , Ringelstein E.B. , Despland P.-A. , Bogousslavsky J.
Published: October 2007

Background and Purpose

—

Transcranial Doppler (TCD) can detect high-intensity transient signals (HITS) in the cerebral circulation. HITS may correspond to artifacts or solid or gaseous emboli. The aim of this study was to develop an offline automated Doppler system allowing the classification of HITS.

Methods

—

We studied 600 HITS in vivo, including 200 artifacts from normal subjects, 200 solid emboli from patients with symptomatic internal carotid artery stenosis, and 200 gaseous emboli in stroke patients with patent foramen ovale. The study was 2-fold, each part involving 300 HITS (100 of each type). The first 300 HITS (learning set) were used to construct an automated classification algorithm. The remaining 300 HITS (validation set) were used to check the validity of this algorithm. To classify HITS, we combined dual-gate TCD with a wavelet representation and compared it with the current “gold standard,” the human experts.

Results

—

A combination of the peak frequency of HITS and the time delay makes it possible to separate artifacts from emboli. On the validation set, we achieved a sensitivity of 97%, a specificity of 98%, a positive predictive value (PPV) of 99%, and a negative predictive value (NPV) of 94%. To distinguish between solid and gaseous emboli, where positive refers now to the solid emboli, we used the peak frequency, the relative power, and the envelope symmetry of HITS. On the validation set, we achieved a sensitivity of 89%, a specificity of 86%, a conditional PPV of 89%, and a conditional NPV of 89%.

Conclusions

—

An automated wavelet representation combined with dual-gate TCD can reliably reject artifacts from emboli. From a clinical standpoint, however, this approach has only a fair accuracy in differentiating between solid and gaseous emboli.
Carotid Stenosis
Authors: Liapis Christos D. , Kakisis John D. , Kostakis Alkiviadis G.
Published: October 2007

Background and Purpose

—

The ability to predict future strokes in asymptomatic patients with carotid stenosis is currently limited. The management of symptomatic patients with <50% stenosis is also debatable. In this context, we performed the following open prospective study to identify factors affecting symptomatology in patients with carotid stenosis.

Methods

—

During 1988–1997, 442 arteries with various degrees of stenosis were followed with the use of color Duplex ultrasonography every 6 months. The main outcome measures were development of symptoms related to the carotid territory and progression in the degree of stenosis. Results of follow-up were analyzed in relation to the traditional risk factors for atherosclerosis as well as the ultrasonographic characteristics of the plaques. Statistical analysis was performed by multiple linear and Cox regression analysis.

Results

—

Mean duration of follow-up was 44 months (range, 12 to 120 months). Significant progression of stenosis occurred in 18.5% of the cases and was more frequent in younger patients (
P
=0.09), in patients with coronary artery disease (
P
=0.02), and in patients with echolucent plaques (
P
=0.02). In regard to clinical presentation, men (
P
=0.07), hypertensives (
P
=0.07), and patients with echolucent plaques (
P
=0.09) showed a trend toward higher frequency of stroke in their history. During the follow-up period, neurological events developed in 12.4% of the cases and were associated with the severity of carotid disease (
P
<0.001), history of neurological events (
P
=0.02), progression of stenosis (
P
=0.002), echolucent plaques (
P
=0.01), and hypertension (
P
=0.02).

Conclusions

—

Factors other than degree of stenosis and history of neurological events are also important in determining high-risk carotid plaque. In our study hypertension, echolucent plaques, and progressive lesions were associated with an increased risk of neurological events. These factors should be taken into consideration in determining treatment strategies for carotid stenosis.
Long-Term Results After Microvascular Decompression in Essential Hypertension
Authors: Frank H. , Schobel H.P. , Heusser K. , Geiger H. , Fahlbusch R. , Naraghi R.
Published: October 2007

Background and Purpose

—

In 1998, 8 patients with severe, intractable arterial hypertension and MR tomography-demonstrated neurovascular contact of a looping artery at the root entry zone of cranial nerves IX and X, causing neurovascular compression, underwent neurosurgical decompression. The short-term results showed a normalization of blood pressure with a markedly reduced antihypertensive drug regimen in 7 patients. To determine the longer-term outcome concerning blood pressure and secondary organ damage after neurovascular decompression, we studied these 8 operated patients prospectively for a mean follow-up of 3.5 years after surgical intervention.

Methods

—

Eight hypertensive patients who had undergone microsurgical decompression were monitored every 6 months after surgery to assess blood pressure (by 24-hour ambulatory pressure readings) and the need for antihypertensive medication. To evaluate secondary organ damage, echocardiographic assessment of left ventricular hypertrophy, fundoscopic assessment of hypertensive lesions, and analysis of renal function and proteinuria were done.

Results

—

Three of the 8 operated patients remained normotensive in the long-term period with decreased antihypertensive medication. Two patients required gradual increases of antihypertensive medication after the first postoperative year, after which arterial blood pressure levels were 10% to 15% lower than preoperative levels. Three patients suffered serious cardiovascular and renal complications, with the incidence of lethal intracerebral hemorrhage in 1 patient and end-stage renal disease in 2 patients, of whom 1 experienced sudden cardiac death.

Conclusions

—

The long-term results verify that microsurgical decompression is a successful alternative therapy in a certain subgroup of patients with arterial hypertension due to neurovascular compression. However, the relevance of the looping artery in the other cases, who did not improve, is not clear. Prospective studies to elucidate the pathophysiological role of neurovascular abnormalities and arterial hypertension are needed.
Collateral Ability of the Circle of Willis in Patients With Unilateral Internal Carotid Artery Occlusion
Authors: Hendrikse Jeroen , Hartkamp Monique J. , Hillen Berend , Mali Willem P.T.M. , Grond Jeroen van der
Published: October 2007

Background and Purpose—The circle of Willis is regarded as the major source of collateral flow in patients with severe carotid artery disease. The purpose of the present study was to assess whether the presence of border zone infarcts is related to the collateral ability of the circle of Willis in symptomatic (transient ischemic attack, minor stroke) and asymptomatic patients with unilateral occlusion of the internal carotid artery (ICA).

Methods—Fifty-one patients (35 symptomatic, 16 asymptomatic) and 53 control subjects were investigated. Patients had unilateral occlusion of the ICA and contralateral ICA stenosis between 0% and 69%. The directions of flow, on the side of the ICA occlusion, and the size of the component vessels in the circle of Willis were investigated with MR angiography.

Results—On average, 92% of the patients without border zone infarcts (n=26) had willisian collateral flow compared with 60% of patients with border zone infarcts (n=25;P<0.05). This increase in collateral flow was caused by the high prevalence of collateral flow via the posterior communicating artery in patients without border zone infarcts (50% versus 12%;P<0.05). No statistically significant relation was found between the pattern of collateral flow via the circle of Willis and the presence of clinical symptoms. Nevertheless, asymptomatic patients with ICA occlusion demonstrated an increased diameter of the anterior communicating artery (P<0.05).

Conclusions—In patients with unilateral ICA occlusion, the presence of collateral flow via the posterior communicating artery in the circle of Willis is associated with a low prevalence of border zone infarcts. Asymptomatic patients with an ICA occlusion do not have an increased collateral function of the circle of Willis.
Caudoputamen Is Damaged by Hypocapnia During Mechanical Ventilation in a Rat Model of Chronic Cerebral Hypoperfusion
Authors: Miyamoto Etsuko , Tomimoto Hidekazu , Nakao Shin-ichi , Wakita Hideaki , Akiguchi Ichiro , Miyamoto Katsuichi , Shingu Koh
Published: October 2007

Background and Purpose

—

Postoperative brain dysfunction, such as delirium, is a common complication of anesthesia and is sometimes prolonged, especially in patients with cerebrovascular disease. In the present study we investigated the effect of hypocapnia during anesthesia on neuronal damage using a rat model of chronic cerebral hypoperfusion.

Methods

—

Chronic cerebral hypoperfusion was induced by clipping the bilateral common carotid arteries in male Wistar rats. Fourteen days after the operation, these animals were mechanically ventilated for 2 hours and then kept in suitable conditions for an additional 14 days. Twenty-four rats were assigned to 4 groups: those with chronic cerebral hypoperfusion with either hypocapnia or normocapnia during anesthesia, and those given sham operation with either hypocapnia or normocapnia. White matter lesions in the brain sections were evaluated with Klüver-Barrera staining. Proliferation of glial cells was estimated with the use of immunohistochemistry of glial fibrillary acidic protein, a marker for astroglia, and CD11b, a marker for microglia. Computer-assisted morphometry was applied to the immunohistochemical results of microtubule-associated protein 2 to evaluate the loss of neurons.

Results

—

The histological damage was localized almost exclusively in the white matter in the rats subjected to chronic cerebral hypoperfusion but without hypocapnia. Neuronal damage and astroglial proliferation occurred with aggravated white matter lesions in the caudoputamen in the rats with chronic cerebral hypoperfusion and hypocapnia. No lesions were observed in sham-operated rats with either hypocapnia or normocapnia.

Conclusions

—

These results indicate that hypocapnia during anesthesia causes tissue damage in the caudoputamen, which may be responsible for long-lasting postoperative delirium in patients with stroke and/or dementia.
Effect and Feasibility of Controlled Rewarming After Moderate Hypothermia in Stroke Patients With Malignant Infarction of the Middle Cerebral Artery
Authors: Steiner Thorsten , Friede Tim , Aschoff Alfred , Schellinger Peter Dieter , Schwab Stefan , Hacke Werner
Published: October 2007

Background and Purpose

—

Moderate hypothermia has been found to reduce intracranial pressure (ICP) significantly in patients who have severe middle cerebral artery infarction. However, during passive rewarming, ICP continuously rises and some patients suffer transtentorial herniation.

Methods

—

We investigated the question of whether slower rewarming leads to slower increase in ICP and slower decrease in cerebral perfusion pressure (CPP). Furthermore, we studied feasibility of slow, controlled rewarming. ICP, CPP, and core body temperature were monitored continuously. Achievement of rewarming protocol was assessed by hit rate of temperature target intervals. Side effects of hypothermia were assessed.

Results

—

Rates of change of both ICP and CPP were correlated significantly with increase in temperature (ICP
r
=0.62,
P
=0.002; CPP
r
=−0.50,
P
=0.017). In feasibility analysis of 13 controlled rewarmed patients, hit rate of temperature target intervals was 63% (median; range 48% to 81%); hit rate within the target interval or below was 79% (median; range 62% to 94%).

Conclusions

—

Slow, controlled rewarming is feasible and may be used for ICP and CPP control after moderate hypothermia for space-occupying infarction.
Time Course of Tissue Plasminogen Activator–Induced Recanalization in Acute Cardioembolic Stroke
Authors: Molina Carlos A. , Montaner Joan , Abilleira Sonia , Arenillas Juan F. , Ribó Marc , Huertas Rafael , Romero Francisco , Alvarez-Sabín Jose
Published: October 2007

Background and Purpose

—

The relationship between arterial recanalization, infarct size, and outcome in patients treated with intravenous thrombolytics remains unclear. Therefore, we aimed to determine the time course of recombinant tissue plasminogen activator (rtPA)-induced recanalization in patients with cardioembolic stroke treated <3 hours from symptom onset and to investigate the relationship between arterial recanalization, infarct volume, and outcome.

Methods

—

We prospectively studied 72 patients with an acute cardioembolic stroke in the middle cerebral artery territory: 24 treated with rtPA at <3 hours and 48 matched controls. Serial transcranial Doppler examinations were performed on admission and at 6,12, 24, and 48 hours. Infarct volume was measured by use of CT at day 5 to 7. Modified Rankin Scale score was used to assess outcome at 3 months.

Results

—

Rate of 6-hour recanalization was higher (
P
<0.001) in the rtPA group (66%) than in the control group (15%). Five (20.8%) rtPA patients and 15 (31.2%) controls recanalized between 6 and 12 hours, and 2 (8.3%) patients and 12 (25%) controls between 12 and 48 hours, respectively. At 48 hours, 75% of rtPA patients and 27% of controls had improved (
P
<0.001). Infarct volume was 50.2±40.3 cm
3
in rtPA patients and 124.8±81.6 cm
3
in controls (
P
<0.001). Moreover, infarct volume was associated strongly (
P
<0.001) with duration of middle cerebral artery occlusion. At 3 months, 14 (58%) rtPA patients and 11 (23%) controls (
P
=0.037) became functionally independent (modified Rankin Scale score ≤2). A close relationship (
P
=0.002) existed between modified Rankin Scale score at 3 months and time to reperfusion. In addition, clinical outcome was associated strongly (
P
=0.001) with degree of 6-hour recanalization. Logistic regression analysis identified National Institutes of Health Stroke Scale score <17 (odds ratio 12.1, 95% confidence interval 2.8 to 68,
P
=0.001) and early recanalization (odds ratio 23.4, 95% confidence interval 5.4 to 96,
P
=0.001) as independent predictors of functional independence at 3 months.

Conclusions

—

Intravenous rtPA is associated with early recanalization, which leads to lower infarct size and better clinical outcome. Early recanalization is a powerful independent predictor of functional independence at 3 months.
The Enemy of My Enemy Is My Friend
Authors: Borgeson Kevin , Valeri Robin M.
Published: October 2007

Through a series of interviews with and observations of Aryan Nations members, this article explores attempts by Aryan Nations to form an alliance with followers of Islamic Jihad and examines how a shared hatred of the Jew provides a basis for such an alliance. The article discusses growing differences between members of Aryan Nations with regard to such an alliance and the role of Christian Identity in their organization. Some members of Aryan Nations believe that their organization and its members should remain tied solely to Christian Identity. Others believe that people from other faiths, specifically Muslims, who share Aryan Nations's goal of defeating Jews, should be allowed to join Aryan Nations. Leaders in Aryan Nations have tried to satisfy both groups by dividing Aryan Nations into two distinct entities, one political and one religious.
Is Bullying a Junior Hate Crime? Implications for Interventions
Authors: Englander Elizabeth
Published: October 2007

Hate crimes and bullying behaviors among children have similarities. Both often focus on “different” individuals as preferred targets, such as those from controversial groups (e.g., homosexuals). Thus, unequal power exists between a bully and his or her victim, and this dynamic precludes the use of equal-power interventions such as mediation. A second similarity is a lack of basic respect for all persons and the subsequent justification of violence against a particular person or group. A third similarity is the predominance of these behaviors among young (juvenile) offenders. These similarities between hate crimes and bullying in children may inform bullying-prevention efforts. Programs need to reduce bullying behaviors by focusing on tolerance of differences, the promotion of positive attitudes toward diversity, and negative attitudes toward hate-based victimization of people who may be different from the mainstream. The Massachusetts Aggression Reduction Center's Anti-Bullying Program provides a model for this approach.
Promoting Respect for Difference on the College Campus
Authors: Rabrenovic Gordana , Levin Jack , Oliver Nelly M.
Published: October 2007

Thirty-nine undergraduate students participated in an experiment to determine the impact of cooperation and fear of terrorism on student support for Muslims on campus. As expected, participants whose fear of terrorism was low expressed significantly greater support for Muslim students than did their more fearful counterparts. Moreover, participants in both the high and the low cooperation condition were significantly more supportive of Muslims on campus than were those who had had no cooperative contact with Muslim students. A significant interaction effect indicates that cooperation had only a salutary impact on support for Muslims among participants who were fearful of another terrorist attack. These results are discussed with respect to their ability to maintain supportive relations between groups on campus during periods of instability.
Making Hate History
Authors: Levin Brian , Amster Sara-Ellen
Published: October 2007

During the last 150 years, New York's remarkable diversity has been both a blessing and a challenge to its police force and its citizens. With the city more populated and diverse than ever, one might expect crime and intergroup conflict to be rampant, when in fact the opposite is true. Although New York is not quite Utopia, the New York Police Department's (NYPD) impressive multiyear effort at combating crime and hate crime in particular has created a noticeably safer and more civil city. Data show that after the state passed new legislation and the NYPD increased support for its Hate Crime Task Force, hate crime in the city dropped dramatically—an important lesson for other cities.
Examining Objectification Theory
Authors: Hill Melanie S. , Fischer Ann R.
Published: October 2007

Many theorists have suggested that living in a culture in which women's bodies are sexually objectified socializes girls and women to treat themselves as objects. This study developed a theory-based measure of cultural sexual objectification and explored the relationship between women's reports of cultural sexual objectification experiences and self-objectification. The possible moderating effects of sexual orientation were explored using hierarchical moderated regressions. The major findings, in a sample of 361 women, were (a) women's reports of sexualized gaze/harassment were significantly related to their own self-objectification, (b) lesbian and heterosexual women reported similar levels of sexualized gaze/harassment, and (c) the relationship between sexualized gaze/harassment and self-objectification was not significantly different for the lesbian and heterosexual subsamples. Potential implications for counseling and directions for future research are discussed.
Christology and the Jewish-Christian Dialogue: A Personal Theological Journey
Authors: Pawlikowski John
Published: October 2007

The Canadian theologian Gregory Baum has argued that chapter four of Vatican II's Nostra Aetate represents the most radical reformulation of the church's ordinary magisterium to emerge from the Council. He is correct. For this chapter on the Church's Relationship to the Jewish People undercut an understanding of that relationship that had persisted since patristic times. In the classical understanding the Church is presented as replacing the Jewish People in the covenantal relationship with God because of the supposed Jewish responsibility for murdering Jesus the Messiah. Traditional Christological proclamation in the Church was very closely connected with this reversal in covenantal membership. Hence the fundamental change of perception on the part of the Council regarding the Church's relationship with Judaism poses a fundamental challenge. If Jews are now to be seen as remaining in a covenantal relationship with God after Christ, then Christological statement today needs significant reformulation. But it must be a reformulation that protects a continued universal dimension for the actions of Christ.
Was Christ Sinless or Impeccable?
Authors: Crisp Oliver D.
Published: October 2007

A number of contemporary theologians deny that Christ is impeccable (incapable of sinning), opting instead for the weaker thesis that Christ was merely sinless (he could have sinned, but did not). In this article, I argue against this position, and for the traditional claim that Christ is incapable of sinning.
Low-Velocity Impact Response and Ultrasonic NDE of Woven Carbon/ Epoxy—Nanoclay Nanocomposites
Authors: Hosur Mahesh V. , Chowdhury Farhan , Jeelani Shaik
Published: October 2007

In the present study, Nanomer® I-28E, organically modified montmorillonite nanoclay supplied by Nanocor Inc., was used to modify SC-15, a toughened epoxy system using sonication route. Different weight percentage ranging from 1—3% of nanoclay was used. The modified epoxy was then used to fabricate 15-layer plain weave carbon/epoxy composite laminates using a vacuum assisted resin transfer molding (VARTM) method. Samples of size 100 × 100 mm were cut from the laminates and were subjected to low-velocity impact loading using an instrumented drop-weight system (Dynatup Model 8210) at three different energy levels of 10, 20 and 30 J. Transient response of the samples was recorded and analyzed in terms to load-energy vs time relations. Impact damage was characterized by utilizing an ultrasonic nondestructive evaluation system (c-scan). Results of the study indicate that the infusion of nanoclay in the system reduced the impact damage though the impact response in terms of the peak load remained mostly unaltered. Reduced damage size was attributed to increased stiffness and resistance to damage progression of the nanophased laminates.
Mechanical Properties and Surface Characteristics of Colombian Wood Composites
Authors: Hiziroglu Salim , Zarate Santiago
Published: October 2007

The objective of this study was to evaluate mechanical properties and surface roughness characteristics of commercially manufactured particleboard, hardboard, and overlaid particleboard panels in Colombia. Patula pine (Pinus patula) and mixed hardwood species were used as raw material for the panels. Average modulus of elasticity (MOE), modulus of rupture (MOR), and internal bond (IB) strength of the five types of particleboard panels were 2481, 16.89, and 0.56 MPa, respectively. Hardboard samples had 28% higher MOE values than those of particleboard panels. Overall, mechanical properties of particleboard panels were not statistically different from each other ( p < 0.1). A skid type profilometer with diamond stylus of 5 μm tip radius and 90 ° tip angle was employed for the experiment. Roughness average (R a), average maximum height of the profile (Rz), and maximum roughness depth (Rmax) were used to evaluate quantitatively surface characteristics of the specimens. Particleboard panel type C had the smoothest surface with average values of 4.15, 35.24, and 50.06 μm for Ra , Rz, and Rmax, respectively. It was found that no statistically ( p < 0.1) significant difference existed between the values of all three parameters taken both parallel and perpendicular to sandmarks of particleboard samples. Hardboard panels had relatively lower roughness values with their superior surface characteristics as compared to those of particleboard samples.
Evolution of the Impact Strength of Carbon Fiber-reinforced PEI Following Exposure to Mechanical, Hygrothermal and Hygrothermomechanical Aging
Authors: Argüelles A. , Fernandez-Canteli A. , Vina J. , Garcia M.A.
Published: October 2007

The instrumented impact test in a falling weight tower was used to obtain the influence of hygrothermal exposure (temperature and humidity), mechanical exposure (flexure load) and the addition of both types of aging (hygrothermomechanical) on the impact properties of a composite with a thermoplastic matrix reinforced with carbon fiber fabric. During the tests, the Charpy specimens employed were positioned so that the hammer struck the piled up plies of the composites transversely. This condition contributed to delamination along the planes of the interface. The energy obtained has two components: initiation and propagation. These components must be calculated independently and could be used to evaluate the behavior of the material subjected to these types of exposure. An analysis was carried out of the specific advantages of this test method in composite materials. From the results, it can be deduced that the fracture toughness of the material does not suffer substantial variations if the exposures are independent. However, their combined action does modify the behavior of the material; in which case, a significant decrease in toughness can be observed.
Effect of Chemical Modification on the Mechanical and Electrical Properties of Banana Fiber Polyester Composites
Authors: Pothan L.A. , George C.N. , Jacob M. , Thomas S.
Published: October 2007

Banana fiber obtained from the sheath of the banana plant, Musa sapientum, has been used in the preparation of composites with polyester matrix. The effect of fiber loading on the dielectric constant, volume resistivity, and dielectric loss factor of the composites were determined with special reference to the effect of frequency. The fibers were modified chemically in order to have better compatibility with the matrix. The surfaces of the modified fibers were characterized using techniques like solvatochromism, zeta potential measurements, X-ray Photo electron spectroscopy (XPS), and Scanning Electron Microscopy (SEM). The effect of fiber surface modification on the mechanical as well as electrical properties of the composites was evaluated. Fiber surface modification was found to influence both mechanical as well as electrical properties of the composite. The mechanical properties were found to be improved based on the improved interaction between the fiber and the matrix which in turn was found to be dependent on the surface polarity of the chemically modified fibers. The value of the dielectric constant was found to be influenced when the fiber loading reaches an optimum value. The dielectric constant values of the treated fiber composites were found to be lower than the untreated composites. The electrical conductivity of the composites was found to be dependent on the chemical modification as well as the fiber loading employed. Maximum conductivity was observed for composites with an optimum fiber loading of 40% as well as for those treated with methacryloxy silane. In addition to the other techniques, conductivity measurements can be used as an effective tool to evaluate interfacial adhesion in composites.
Generalized Technique for Cumulative Damage Modeling of Composite Laminates
Authors: Shokrieh Mahmood M. , Zakeri Mahnaz
Published: October 2007

This article introduces an iterative model to predict the fatigue behavior of fiber reinforced laminated composites under general loading conditions. The model simulates the damage progress and subsequent material property degradation of composite laminates and predicts their fatigue life by using a three-stage procedure. In the first stage, state of stresses in the whole component is specified. Then, multi-axial stresses of each element are utilized to damage assessment by using a newly developed damage estimation technique. Considering each element as an orthotropic material, stiffness degradation due to the induced damage is calculated based on two sets of material property degradation rules. For this aim, a generalized approach is used for gradual and sudden material property degradation. In order to evaluate the model, a macro program is developed that simulates the fatigue behavior of unidirectional and multidirectional composite laminates. The results of the model are consistent with available experimental data. Using this program, some fatigue life predictions are also accomplished for laminates with arbitrary stacking sequences.
Experimental Testing of Concrete Beams Reinforced with Carbon FRP Bars
Authors: Rafi Muhammad Masood , Nadjai Ali , Ali Faris
Published: October 2007

Most of the research on the fiber reinforced polymer (FRP) bar reinforced structures employed glass FRP (GFRP) bars. The results of tests, which were conducted on the carbon FRP (CFRP) bar reinforced concrete beams, are reported in this article. The beams reinforced with conventional steel rods were tested as control specimens. Nearly equal crack spacing and number of cracks were noted in both types of beams, at all stages of loading. The bond characteristics of the CFRP bars were found to be satisfactory. The ACI code equation over-estimated the stiffness of the CFRP reinforced beams and as a result theoretical deflection, predicted by the ACI code method, was found to be less than the recorded deflection.
Time-to-failure of Compressively Loaded Composite Structures Exposed to Fire
Authors: Kim Jihan , Lee Sung W. , Kwon Soonwook
Published: October 2007

A combined thermal-structural analysis methodology based on finite element modeling is developed for the analysis of composite structures exposed to high temperatures due to fire. A simplified heat transfer model proposed by Lattimer is adopted for the thermal response model to determine temperature distributions in composite structures with and without insulation while an assumed strain solid shell finite element formulation is adopted for the structural response model with a material model that takes into account the effects of temperature on modulus and charring. Numerical analyses are carried out to determine the time-to-failure via the global buckling of simply supported and clamped wide columns of an E-glass/ vinylester woven composite material with and without insulation subjected to heat flux and compression. Large deflection non-linear analyses are also conducted to determine the displacement of the columns as the temperature changes. The beneficial effect of insulation on time-to-failure is demonstrated via numerical calculations. Sensitivity analyses are carried out to examine the effect of variation in the glass transition temperature on the time-to-failure of the composite columns.
Effects of Etoricoxib and Comparator Nonsteroidal Anti‐Inflammatory Drugs on Urinary Sodium Excretion, Blood Pressure, and Other Renal Function Indicators in Elderly Subjects Consuming a Controlled Sodium Diet
Authors: Schwartz Jule I. , Thach Chau , Lasseter Kennet C. , Miller Jutta , Hreniuk David , Hilliard Debora A. , Snyder Kare M. , Gertz Barr J. , Gottesdiener Keit M.
Published: October 2007

This multicenter, double‐blind, randomized, placebo‐controlled, parallel‐group study assessed renal function during dosing with etoricoxib 90 mg daily, celecoxib 200 mg twice daily, and naproxen 500 mg twice daily. Male and female subjects 60 to 81 years old (n = 85), in sodium balance on a controlled, normal sodium diet, were treated for 15 days. There were no clinically meaningful between‐treatment differences in urinary sodium excretion, creatinine clearance, body weight, or serum electrolytes during the 2 weeks of treatment. Etoricoxib and celecoxib had no effect on the urinary thromboxane metabolite, 11‐dehydrothromboxane B2, while significantly decreasing the urinary prostacyclin metabolite, 2,3‐dinor‐6‐keto PGF1α. Decreases were greater for both metabolites following naproxen. Ambulatory systolic blood pressures were significantly higher than placebo for all treatments, with moderately greater increases for etoricoxib relative to other active treatments on day 14. Ambulatory diastolic blood pressures were significantly higher than placebo for etoricoxib and naproxen but not for celecoxib.
The Number of Sick Persons in a Cohort
Authors: Diehr Paula , Derleth Ann , Newman Anne B. , Liming Cai
Published: October 2007

Planning for future health needs of older adults requires a better understanding of the trajectories of health and sickness with age. The authors calculated the number of sick persons over time in a “research” cohort of older adults followed for up to 14 years, and also in a synthetic birth cohort. In the research cohort, the authors calculated the actual number of persons in each health state over time, using eight different definitions of “sick.” For the birth cohort, the authors estimated the number of sick persons each year after birth. The number of sick persons in the research cohort was approximately constant for 14 years, for all definitions of “sick.” The number sick in the birth cohort was approximately constant from ages 55 to 80 and then declined. The relative excess of sick persons in later life is caused by a decline in the number of healthy persons rather than an increase in the number who are sick. The number of sick current Medicare enrollees may be approximately constant for 14 years. These insights may help in planning for the aging population.
Deference as a Form of Reciprocity Among Residents in Assisted Living
Authors: Beel-Bates Cindy A. , Ingersoll-Dayton Berit , Nelson Erika
Published: October 2007

Although the ability to provide support to others may diminish with age, the desire to reciprocate persists. Using social exchange theory, this article examines deference as one form of exchange. Based on a sample of 31 residents age 85 and older in assisted living facilities, data were gathered via a semi-structured interview that was audiotaped and transcribed. This study analyzes their responses to open-ended questions using qualitative methods. Findings indicate that these “oldest old” respondents reciprocate for the support they receive from family and staff via deference. Four forms of deference are identified: participation, pleasantness, cooperation, and gratitude. In addition, the psychological costs and rewards of deference are examined from the elders' perspective.
Surface Coating and Metal-Based Organic Additives—Approaches for FRSS PVC Cables
Authors: Sharma Sunil K. , Saxena N.K.
Published: October 2007

Polyvinyl chloride (PVC) is one of the most widely used polymers today. One of its major applications is in electrical and control cables. Although PVC is intrinsically self-extinguishing, it supports flame spread along its length because of the additives used during processing. The spread of fire along electrical cables may be alleviated either by using flame-retardant smoke-suppressant (FRSS) additives or by applying fire-retardant intumescent coatings to the surface of the cable sheath. The intumescent coating also acts as a fire-protective barrier for electrical cables. Plasticized PVC compositions incorporating a molybdenum-based organic (MBO) complex were prepared and evaluated for their fire performance. Excellent smoke suppression was observed in the specimens modified using the complex, which acts as an FRSS additive. The limiting oxygen index (LOI) was also found to be fairly high, particularly when the PVC samples were plasticized with a phosphate plasticizer. FRSS intumescent coatings were applied on PVC-sheathed electrical cables. Their fire performance was evaluated using national and international standard procedures. Significantly low levels of smoke generation was observed along with zero flame spread when the coated cables were exposed to standard test conditions. The formulations used in both the treatments — coating as well as additive — offer improved resistance to ignition, flame spread and smoke generation.