bluuebunny/crossref_metadata_2025 huggingface dataset:
Erectile Function is Improved in Aged Rats by PnTx2-6, a Toxin from Phoneutria nigriventer Spider Venom
Authors: Nunes Kenia P. , Toque Haroldo A. , Borges Marcia H. , Richardson Michael , Clinton Webb R. , de Lima Maria Elena
Published: August 2012

Introduction

Age-associated erectile dysfunction (ED) involves a decrease in nitric oxide (NO) availability and impaired relaxation. PnTx2-6, a toxin from the Phoneutria nigriventer spider, has been demonstrated to improve erectile function via NO/cyclic guanosine monophosphate (cGMP) pathway. This spider’s venom is characterized by several symptoms, including erection. PnTx2-6 has been implicated in this phenomenon. Animal venoms have been postulated as potential drugs to treat ED.

Aim

PnTx2-6 toxin improves erectile function in aged rats via NO/cGMP. We investigated the effect of PnTx2-6 in the erectile function of aged rats.

Main Outcome Measures

ED was evaluated through changes in intracavernosal pressure/mean arterial pressure ratio during electrical field stimulation (EFS) of the pelvic ganglion of aged and adult rats (70 vs. 14 weeks). In functional studies, EFS-induced relaxation of corpus cavernosum (CC) strips were performed with or without PnTx2-6 (10-8M).

Results

The decrease in erectile function associated with age was partially restored 15–20 minutes after injection of PnTx2-6 and further improved by sildenafil. PnTx2-6 enhanced EFS-induced relaxation, as well as cGMP levels in CC, from young and aged rats. Relaxation due to PnTx2-6 was further increased after 30 minutes incubation with Y-27632, a Rho-kinase inhibitor (10-6 M), in aging CC. Nitric oxide synthase (NOS) activity in aged and young cavernosal tissue was increased by incubation with PnTx2-6 (10 minutes). However, this toxin did not modify NOS expression.

Conclusion

PnTx2-6 improves penile relaxation in aged rats, via increased NOS activity and NO release, resulting in enhanced cGMP levels.
Hungarian “Jailhouse Rock”: Incidence and Morbidity of Vaseline Self-Injection of the Penis
Authors: Rosecker Ágnes , Bordás Noémi , Pajor László , Bajory Zoltán
Published: August 2012

Introduction

Vaseline self-injection into the penis is currently a popular procedure in prisons. Since such injections are illegal, severe complications of the procedure can often remain hidden.

Aim

To identify the incidence, motivation, and morbidity of Vaseline self-injection into the penis among inmates.

Methods

A total of 4,735 inmates at the largest Hungarian prisons were asked to complete a questionnaire relating to their sexual life, whether they had self-injected Vaseline into their penis, the motivation leading them to resort to Vaseline self-injection, any complications observed and the level of satisfaction attained.

Main Outcome Measures

A 17-point questionnaire on the circumstances, motivations, and complications of Vaseline self-injection among prisoners.

Results

Of the 1,905 responders, 15.7% admitted Vaseline self-injection. Only around one-fifth of the Vaseline injected subjects had not been satisfied with the original size of their penis and their sexual life up to the time of the injection, a proportion similar to that among Vaseline nonusers. While the satisfaction with the sexual life became significantly worse after the Vaseline injection, the satisfaction with the penis size did not change and an erectile dysfunction developed de novo in 21.4% of cases. The most common motivation for self-injection was a recommendation by another inmate; it was rarely recommended by a sexual partner. Complications had developed among 25.4% of the Vaseline users and 50.3% of them were not satisfied with the result of the Vaseline injection. Of the Vaseline users, 22.4% regretted the self-injection, while the rate among those who had developed complications was 53%.

Conclusions

The self-injection of Vaseline into the penile skin proved to be somewhat of a trend among these inmates. The complications depended mainly on the amount of Vaseline injected, the poor hygienic circumstances, and the personal tolerability. Increased awareness is needed for the prevention of this social, psychological, and physical problem.
The complement‐mediated prozone effect in the Luminex single‐antigen bead assay and its impact on HLA antibody determination in patient sera
Authors: Weinstock C. , Schnaidt M.
Published: August 2012

The Luminex xMAP system has become an important tool for HLA antibody screening and identification in sera of transplant patients. Recently, the Luminex single antigen bead assay was shown to be prone to an artefact, the so called prozone phenomenon: Sera with high titer HLA antibodies gave negative results when tested neat, but reacted strongly positive after 1:10 dilution. We also observed such a phenomenon and found that it was most likely caused by the complement component 1 (C1) by competitively displacing the detection antibodies. In this article we review the complement‐mediated prozone effect and other mechanisms of interference with solid phase assays, and we discuss possible consequences for HLA antibody testing with the Luminex SAB assay.
Differential vulnerability to predation in two sympatric whelks is mediated by juvenile traits
Authors: Carrasco Sergio A. , Phillips Nicole E.
Published: August 2012

In many taxa, initial differences in offspring size play an important role in mediating subsequent performance; however, the consequences of interspecific variation in size for the performance of co‐occurring taxa have been rarely examined. We used the whelks Cominella virgata and C. maculosa, which co‐occur on rocky shores throughout their life cycles, to examine the vulnerability of early life‐stages to native predators under controlled laboratory conditions. Among all the predators evaluated (the cushion sea star Patiriella spp., the olive rockfish Acanthoclinus fuscus, the oyster borer snail Haustrum scobina, the smooth shore crab Cyclograpsus lavauxi, and the pebble crab Heterozius rotundifrons), hatchlings of both species (C. virgata: ~3 mm shell length [SL] and C. maculosa: ~1.5 mm SL) were especially vulnerable to the smooth shore crab Cy. lavauxi, the only potential predator in which mortality was greater than in the control treatment. Small shore crabs (~8 mm carapace width [CW]) were unable to eat hatchlings of either whelk species, whereas medium and large shore crabs (~12 and ~18 mm CW, respectively) consumed hatchlings of both prey species. Hatchlings of C. virgata were less vulnerable to predation by medium crabs than large ones, and those of C. maculosa were equally vulnerable to both sizes of crabs. In hatchlings of both prey species, shell length and shell thickness increased over time. Two months after hatching, only individuals of C. virgata had reached a size refuge from predation. Our results show that interspecific vulnerability to predators can be mitigated by larger sizes and thicker shells at hatching; nonetheless, our results also suggest that other species‐specific factors, such as juvenile growth rate, may also play key roles in determining the vulnerability of hatchling and juvenile snails to shell‐crushing predators.
Feasibility of infrared spectroscopy with pattern recognition techniques to identify a subpopulation of mares at risk of producing foals diagnosed with failure of transfer of passive immunity
Authors: Riley CB , McClure JT , Low‐Ying S , Dolenko BK , Somorjai RL , Shaw RA
Published: August 2012

Objective

To assess the feasibility of a serum‐based test using infrared spectroscopy to identify a subpopulation of mares at risk of producing foals susceptible to failure of passive transfer of immunity (FPT) because of mare‐associated factors.

Materials and methods

Serum was collected from post‐parturient mares (n= 126) and their foals at 24–72 hof age. A radial immunodiffusionIgGtest was used to determine each foal's serumIgGconcentration. Infrared absorbance spectra of dam sera were collected in the wave number range of 400–4000 cm−1. Following data preprocessing, pattern recognition techniques were used to identify spectroscopic information capable of distinguishing between mares withFPTfoals and those with normal foals. The sensitivity and specificity of infrared spectroscopy to detect risk‐positive mares were calculated.

Results

Five wave number regions were identified as optimal for distinguishing between the two groups of mares: 740.9–785.2 cm−1, 796.8–816.0 cm−1, 970.4–993.5 cm−1, 1371.6–1406.3 cm−1and 1632.0–1659.0 cm−1. Based upon the infrared spectroscopic information within these discriminatory subregions, the spectra provided the risk status of the mares with a classification success rate of 81.0%. The sensitivity of the classification system was 85.7% and specificity was 80.0%.

Conclusion

This preliminary study demonstrates that infrared spectra of dam serum have the potential to provide the basis for a new periparturient screening method for a subpopulation of mares at risk of having a foal susceptible toFPT. Further development may provide an economic and rapid technique for the pre‐parturient assessment of mares.
Clinical evaluation of alfaxalone as an anaesthetic induction agent in cats less than 12 weeks of age
Authors: O'Hagan BJ , Pasloske K , McKinnon C , Perkins NR , Whittem T
Published: August 2012

Objective

To assess the clinical suitability of alfaxalone as an anaesthetic induction and maintenance agent for kittens aged less than 12 weeks.

Materials and methods

The study group comprised 34 kittens aged less than 12 weeks that were presented for surgical desexing. They were aged by dentition, examined and weighed prior to premedication with acepromazine, atropine and morphine. At 20–30 min after premedication, animals were anaesthetised with intravenous alfaxalone administered to effect, using a target maximum expected dose of 5 mg/kg. All cats were intubated: 25 were maintained with isoflurane in oxygen administered with a non‐rebreathing circuit and 8 were maintained by supplemental intravenous administration of alfaxalone. Subjective measures of anaesthetic quality and vital signs were recorded from enrolment to recovery. Cats receiving supplemental alfaxalone for maintenance were evaluated for time to first supplemental dose and the total dose of supplemental alfaxalone (mg/kg/h). Descriptive and comparative statistics were used to analyse and present collected data.

Results

The mean (±SD) dose of alfaxalone for induction was 4.7 ± 0.5 mg/kg body weight. Subjective measures of anaesthetic quality indicated acceptable induction, maintenance and recovery standards. Measured cardiovascular and respiratory parameters were well maintained.

Conclusion

Alfaxalone in 2‐hydroxypropyl‐beta‐cyclodextrin (Alfaxan®) is a suitable injectable anaesthetic induction agent for juvenile cats aged less than 12 weeks requiring anaesthesia. Maintenance of anaesthesia with supplemental doses of alfaxalone may be a suitable alternative in kittens when the use of inhalant anaesthetic maintenance is not feasible.
Ischemic Postconditioning Diminishes Matrix Metalloproteinase 9 Expression and Attenuates Loss of the Extracellular Matrix Proteins in Rats Following Middle Cerebral Artery Occlusion and Reperfusion
Authors: Liu Xiang‐Rong , Luo Mei , Yan Feng , Zhang Chen‐Cheng , Li Si‐Jie , Zhao Hai‐Ping , Ji Xun‐Ming , Luo Yu‐Min
Published: August 2012

Aims

Ischemic postconditioning (IPostC) has been proved to have neuroprotective effects for cerebral ischemia, but the underlying mechanism remains elusive. This study aimed at validating the neuroprotective effects of IPostC and investigating whether the neuroprotection of IPostC is associated with matrix metalloproteinase 9 (MMP9) and the extracellular matrix proteins, laminin and fibronectin, following cerebral ischemia/reperfusion in rats.

Methods

The rats in middle cerebral artery occlusion (MCAO) group underwent MCAO and reperfusion, and the animals in MCAO + IPostC group were treated by occluding bilateral common carotid arteries for 10 seconds and then reperfusing for 10 seconds for five episodes at the beginning of MCAO. Apoptosis was detected with terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The expression of MMP9, laminin, and fibronectin was measured with immunofluorescence and enzyme‐linked immunosorbent assay.

Results

IPostC reduced brain edema and infarct volume and improved the neurological function. Furthermore, IPostC decreased cell apoptosis compared with the MCAO group. Compared to the MCAO group, IPostC treatment reduced MMP9 expression. Moreover, the results showed that the expression of laminin and fibronectin significantly increased in the MCAO + IPostC group compared to the MCAO group.

Conclusion

These findings indicated that diminishment of MMP9 expression and the attenuation of degradation of laminin and fibronectin may be involved in the protective mechanisms of postconditioning against cerebral ischemia/reperfusion injury.
Designer Treps: An Evolution
Authors: Eder Ryan
Published: August 2012

As designers learn new skills and get more involved in business and strategy, some of them naturally gravitate to starting their own companies.
Planting Gardens on Main Street: Changing a Community Through Design
Authors: Doehler Steven J.
Published: August 2012

He opened a door and was surprised by what walked through it.
Diversity, Polarity, Inclusivity: Finding Balance in Design Leadership
Authors: Maciver Fiona
Published: August 2012

The author studied four design consultancies and found that design leadership cuts a broader swath than it once did—particularly in new product development.
La Ruche qui Dit Oui: Reconnecting Communities with Food
Authors: Ortiz Natalie
Published: August 2012

A French industrial designer who is also a chef has devised a brilliant solution for bringing together food producers and the communities that depend on them.
Firstborn and SoBe: A Playful Partnership
Authors: Kim Yu‐Jin , Reuther Karen
Published: August 2012

Digital design agencies are learning to take a more entrepreneurial approach to finding and working with new clients.
The Relevance of Design Thinking in Retail: An Indian Perspective
Authors: Pradhan Swapna
Published: August 2012

Interested consumers, rising levels of consumption, and a young population—what's not to like? But retail in India is not that simple.
Design Insights from User Research and Crowdsourcing
Authors: Petersen Søren Ingomar , Hussain Sofia
Published: August 2012

Which skills do designers need as they try to reach markets in areas that are extremely different culturally from their own?
The Value of Design in Developing Markets: An Indian Insight
Authors: Parida Alpana
Published: August 2012

“Reinterpreting global brands in a local context” versus “transposed design.”
Reframing Our Ways of Working, and Stretching the Creative Spirit
Authors: Thorpe Mark
Published: August 2012

To develop a more entrepreneurial spirit, try looking beyond legacy processes and ways of working. You may be surprised at the results.
Severe hindlimb lameness and pathological femur fracture in a horse secondary to haemangiosarcoma
Authors: Mahne A. T. , Marais H. J. , Rubio‐Martinez L. M. , Williams J. H.
Published: August 2012

An 18‐year‐old Warmblood stallion was presented for an acute onset nonweightbearing right hindlimb lameness following a mild lameness of 2 weeks' duration. Severe swelling was present in the right femoral area. Despite extensive diagnostic procedures, no definitive diagnosis could be made. Packed red cell volume was persistently low. The horse improved with supportive treatment and was discharged at the owner's request. The horse presented 4 days later for bleeding from a previously made incision on the lateral femoral area. Due to deterioration of his condition, the stallion was subjected to euthanasia. Diagnosis of disseminated haemangiosarcoma, affecting primarily the hindlimb musculature and leading to pathological fracture of the femur was made at necropsy and subsequent histopathology.
Axillary wounds in horses and the development of subcutaneous emphysema, pneumomediastinum and pneumothorax
Authors: Joswig A. , Hardy J.
Published: August 2012

Equine axillary wounds are common in horses. Severe and potentially life‐threatening complications that can result from axillary wounds include subcutaneous emphysema, pneumomediastinum and pneumothorax. This report describes the occurrence of these complications and appropriate treatment. Case records of 7 horses after sustaining an axillary wound are reviewed. Of these cases, all 7 developed subcutaneous emphysema, 5 developed a pneumomediastinum and 4 developed a pneumothorax. The time between the wound occurrence and the development of subcutaneous emphysema was able to be determined in 5 of the 7 cases. The mean ± s.d. time for the development of subcutaneous emphysema following initial injury was 3.2 ± 0.84 days (range 2–4 days). Resolution of subcutaneous emphysema was not achieved until the treatment included packing the wound to stop it from acting as a one‐way valve. Horses with a pneumothorax in respiratory distress were managed with thoracocentesis or placement of thoracic drains. Horses with a pneumothorax but without respiratory distress were treated with conservative management. All horses survived to discharge.
Academic perceptions of the research evidence base in work and organizational psychology: A European perspective
Authors: Guest David E. , Zijlstra Fred R. H.
Published: August 2012

There has been a growing interest in evidence‐based management. A core component is a body of high‐quality research evidence to inform practice. Initial research with human resource managers in the United States and the Netherlands reveals only modest knowledge about a number of ‘widely documented’ research findings. However, it is unclear whether research experts would display any greater agreement about the research evidence. The present study addresses this issue by exploring levels of agreement about the quality of the research evidence base in work and organizational (W/O) psychology using a pan‐European sample of 75 senior academic W/O psychologists who completed two rounds of a study, first identifying core findings in the field of W/O psychology and then reporting levels of agreement about them. The results show that there were only seven of 24 core findings on which over 75% agreed that there was good‐quality evidence. The challenges of developing and utilizing an evidence‐based approach are discussed and it is concluded, in agreement with Briner and Rousseau (2011a), that there is some way to go before W/O psychologists can begin to feel confident about the quality of much of their research evidence.
Molecular cloning of rice serotonin N‐acetyltransferase, the penultimate gene in plant melatonin biosynthesis
Authors: Kang Kiyoon , Lee Kyungjin , Park Sangkyu , Byeon Yeong , Back Kyoungwhan
Published: August 2012

Because of the absence of an arylalkylamine N‐acetyltransferase (AANAT) homolog in the plant genome, the proposal was made that a GCN5‐related N‐acetyltransferase superfamily gene (GNAT) could be substituted for AANAT. To clone rice serotonin N‐acetyltransferase (SNAT), we expressed 31 rice GNAT cDNAs in Escherichia coli and screened SNAT activity by measuring N‐acetyltryptamine after application with 1 mm tryptamine. GNAT5 was shown to produce high levels of N‐acetyltryptamine in E. coli, suggesting a possible rice SNAT. To confirm SNAT activity, the GNAT5 protein was purified through affinity purification from E. coli culture. The purified recombinant GNAT5 showed high SNAT enzyme activity catalyzing serotonin into N‐acetylserotonin. The values for Km and Vmax were 385 μm and 282 pmol/min/mg protein, respectively. An in vitro enzyme assay of purified SNAT showed N‐acetylserotonin formation to be proportional to enzyme concentration and time, with peak activity at pH 8.8. High substrate concentrations above 1 mm serotonin inhibited SNAT activity. Finally, the mRNA level of SNAT was higher in shoots than in roots, but it was expressed constitutively, unlike N‐acetylserotonin methyltransferase (ASMT), the terminal enzyme in melatonin synthesis. These results suggest that ASMT rather than SNAT is the rate‐limiting enzyme of melatonin biosynthesis in plants.
Melatonin ameliorates low‐grade inflammation and oxidative stress in young Zucker diabetic fatty rats
Authors: Agil Ahmad , Reiter Russel J. , Jiménez‐Aranda Aroa , Ibán‐Arias Ruth , Navarro‐Alarcón Miguel , Marchal Juan Antonio , Adem Abdu , Fernández‐Vázquez Gumersindo
Published: August 2012

The aim of this study was to investigate the effects of melatonin on low‐grade inflammation and oxidative stress in young male Zucker diabetic fatty (ZDF) rats, an experimental model of metabolic syndrome and type 2 diabetes mellitus (T2DM). ZDF rats (n = 30) and lean littermates (ZL) (n = 30) were used. At 6 wk of age, both lean and fatty animals were subdivided into three groups, each composed of 10 rats: naive (N), vehicle treated (V), and melatonin treated (M) (10 mg/kg/day) for 6 wk. Vehicle and melatonin were added to the drinking water. Pro‐inflammatory state was evaluated by plasma levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and C‐reactive protein (CRP). Also, oxidative stress was assessed by plasma lipid peroxidation (LPO), both basal and after Fe2+/H2O2 inducement. ZDF rats exhibited higher levels of IL‐6 (112.4 ± 1.5 pg/mL), TNF‐α (11.0 ± 0.1 pg/mL) and CRP (828 ± 16.0 µg/mL) compared with lean rats (IL‐6, 89.9 ± 1.0, P < 0.01; TNF‐α, 9.7 ± 0.4, P < 0.01; CRP, 508 ± 21.5, P < 0.001). Melatonin lowered IL‐6 (10%, P < 0.05), TNF‐α (10%, P < 0.05), and CRP (21%, P < 0.01). Basal and Fe2+/H2O2‐induced LPO, expressed as malondialdehyde equivalents (µmol/L), were higher in ZDF rats (basal, 3.2 ± 0.1 versus 2.5 ± 0.1 in ZL, P < 0.01; Fe2+/H2O2‐induced, 8.7 ± 0.2 versus 5.5 ± 0.3 in ZL; P < 0.001). Melatonin improved basal LPO (15%, P < 0.05) in ZDF rats, and Fe2+/H2O2‐ induced LPO in both ZL (15.2%, P < 0.01) and ZDF rats (39%, P < 0.001). These results demonstrated that oral melatonin administration ameliorates the pro‐inflammatory state and oxidative stress, which underlie the development of insulin resistance and their consequences, metabolic syndrome, diabetes, and cardiovascular disease.
Influence of oxytetracycline on carprofen pharmacodynamics and pharmacokinetics in calves
Authors: Brentnall C. , Cheng Z. , Mckellar Q. A. , Lees P.
Published: August 2012

A tissue cage model of inflammation in calves was used to determine the pharmacokinetic and pharmacodynamic properties of individual carprofen enantiomers, following the administration of the racemate.RS(±) carprofen was administered subcutaneously both alone and in combination with intramuscularly administered oxytetracycline in a four‐period crossover study. Oxytetracycline did not influence the pharmacokinetics ofR(−) andS(+) carprofen enantiomers, except for a lower maximum concentration (Cmax) ofS(+) carprofen in serum after co‐administration with oxytetracycline.S(+) enantiomer means for area under the serum concentration–time curve (AUC0–96hwere 136.9 and 128.3 μg·h/mL and means for the terminal half‐life (T½k10) were = 12.9 and 17.3 h for carprofen alone and in combination with oxytetracycline, respectively.S(+) carprofenAUC0–96hin both carprofen treatments and T½k10for carprofen alone were lower (P < 0.05) thanR(−) carprofen values, indicating a small degree of enantioselectivity in the disposition of the enantiomers. Carprofen inhibition of serum thromboxane B2ex vivowas small and significant only at a few sampling times, whereasin vivoexudate prostaglandin (PG)E2synthesis inhibition was greater and achieved overall significance between 36 and 72 h (P < 0.05). Inhibition ofPGE2correlated with mean time to achieve maximum concentrations in exudate of 54 and 42 h for both carprofen treatments forR(−) andS(+) enantiomers, respectively. Carprofen reduction of zymosan‐induced intradermal swelling was not statistically significant. These data provide a basis for the rational use of carprofen with oxytetracycline in calves and indicate that no alteration to carprofen dosage is required when the drugs are co‐administered.
The isolated perfused equine distal limb as anex vivomodel for pharmacokinetic studies
Authors: Friebe M. , Stahl J. , Kietzmann M.
Published: August 2012

Even though intra‐articular injections play an important role in the treatment of joint‐related lameness in horses, little is known about pharmacokinetic properties of substances used. Therefore, anex vivomodel for pharmacokinetic studies was developed using distal forelimbs of slaughtered horses. The extremity was perfused with gassed Tyrode solution for up to 8 h. Tissue viability was confirmed by measurements of glucose consumption, lactate production, and lactate dehydrogenase activity in the perfusate. Standard criteria for tissue viability had been determined in preliminary experiments (n = 11), which also included histological examinations of the joint capsule. As the model's first implementation, the articular efflux rate of betamethasone (BM), administered asBMdisodium phosphate intra‐articularly to the fetlock joint (4 mgBM/joint), was investigated. The concentration ofBMin the venous perfusate of the radial vein was measured by means of high‐performance liquid chromatography. The averageBMefflux rate per minute was calculated to be 5.1 μg/min with values ranging from 9 μg/min to 2.9 μg/min. 7.5 h after i.a. application, 2.3 mgBMhad left the joint via the radial vein. Using this inexpensive setup, the presented model allows studying a variety of pharmacological topics without the ethical limitations of animal studies.
Crossing the Threshold: The Spillover of Community Racial Diversity and Diversity Climate to the Workplace
Authors: Ragins Belle Rose , Gonzalez Jorge A. , Ehrhardt Kyle , Singh Romila
Published: August 2012

We examined the spillover of community diversity to the workplace using a sample of 2,045 professionals living in communities across the U.S. Spillover effects were examined using 2 measures of community diversity: the degree to which employees were racially or ethnically similar to others in their community and perceptions of their community's diversity climate. Aligned with theories of group threat and racial segregation, Whites who were racially dissimilar to their communities expressed stronger intentions to leave their communities, and ultimately their workplaces, than those living in primarily White communities. However, community diversity climate offset these relationships; Whites who lived in communities that were racially dissimilar to them, but experienced the climate as inclusive, had lower moving intentions than those in communities that were experienced as racially intolerant. In contrast, for people of color, community diversity climate, rather than racial similarity to the community, predicted moving intentions. For both groups, the diversity climate in the community predicted moving intentions, which in turn predicted work turnover intentions, job search behaviors, and physical symptoms of stress at work. These findings suggest that the intention to leave one's community, and ultimately one's workplace, is influenced by community experiences and the community's perceived diversity climate.
Evaluating Six Common Stereotypes About Older Workers with Meta‐Analytical Data
Authors: Ng Thomas W. H. , Feldman Daniel C.
Published: August 2012

This study evaluates the cumulated empirical evidence on 6 common age stereotypes. These stereotypes suggest that older workers are: (a) less motivated, (b) generally less willing to participate in training and career development, (c) more resistant and less willing to change, (d) less trusting, (e) less healthy, and (f) more vulnerable to work‐family imbalance. The meta‐analysis included 418 empirical studies (N= 208,204) and examined the relationships of age to 39 variables representing the content domain of age stereotypes. The only stereotype consistent with empirical evidence is that older workers are less willing to participate in training and career development activities. The paper concludes with implications for future theory development and management practice.
Navigating the Black Hole: Explicating Layers of Job Search Context and Adaptational Responses
Authors: Wanberg Connie , Basbug Gokce , Van Hooft Edwin A.J. , Samtani Archana
Published: August 2012

Via a qualitative study, we introduce and elucidate 5 layers of context‐related job search demands (omnibus, organizational, social, task, and personal) that are encountered by both employed and unemployed job seekers. We develop a process model to portray the mechanisms (managing mood and motivation, feedback/help seeking, and self‐reflection/learning) through which these context‐related demands are related to several important job search outcomes. We provide new insight into employed job seekers, showing that they report the job search as full of difficulties, obstacles, and challenges, and that some of these demands parallel those that unemployed job seekers face.
Reviewing, Categorizing, and Analyzing the Literature on Black–White Mean Differences for Predictors of Job Performance: Verifying Some perceptions and Updating/Correcting Others
Authors: Bobko Philip , Roth Philip L.
Published: August 2012

In both theoretical and applied literatures, there is confusion regarding accurate values for expected Black–White subgroup differences in personnel selection test scores. Much confusion arises because empirical estimates of standardized subgroup differences (d) are subject to many of the same biasing factors associated with validity coefficients (i.e., d is functionally related to a point‐biserial r). To address such issues, we review/cumulate, categorize, and analyze a systematic set of many predictor‐specific meta‐analyses in the literature. We focus on confounds due to general use of concurrent, versus applicant, samples in the literature on Black–White d. We also focus on potential confusion due to different constructs being assessed within the same selection test method, as well as the influence of those constructs on d. It is shown that many types of predictors (such as biodata inventories or assessment centers) can have magnitudes of d that are much larger than previously thought. Indeed, some predictors (such as work samples) can have ds similar to that associated with paper‐and‐pencil tests of cognitive ability. We present more realistic values of d for both researcher and practitioner use. Implications for practice and future research are noted.
A Meta‐Analytic Structural Model of Dispositonal Affectivity and Emotional Labor
Authors: Kammeyer‐Mueller John D. , Rubenstein Alex L. , Long David M. , Odio Michael A. , Buckman Brooke R. , Zhang Yiwen , Halvorsen‐Ganepola Marie D. K.
Published: August 2012

The exponential growth of the service economy has increased the attention that organizational researchers have paid to the concept of emotional labor. Although much progress has been made in the field, few studies have provided an integrated picture of how individual dispositions, perceived display rules, and emotional labor behaviors shape employee outcomes. To clarify and compare results across this growing body of literature, a quantitative review was developed, along with a theoretically derived path diagram of key emotional labor constructs. Evidence from our structural meta‐analytic model based on 116 primary studies demonstrates that examining affective dispositions and emotional labor constructs and the pattern of positive and negative results helps to clarify and add specificity to the literature. Results were consistent with the perspective that surface acting emotion regulation strategies have a pattern of negative relationships with work outcomes of job satisfaction and stress/exhaustion (but not with job performance), whereas deep acting emotion regulation strategies have a pattern of positive relationships with all of these work outcomes.
Nonlocal Flügge Shell Model for Vibrations of Double-Walled Carbon Nanotubes With Different Boundary Conditions
Authors: Ansari R. , Arash B.
Published: August 2012

In this paper, the vibrational behavior of double-walled carbon nanotubes (DWCNTs) is studied by a nonlocal elastic shell model. The nonlocal continuum model accounting for the small scale effects encompasses its classical continuum counterpart as a particular case. Based upon the constitutive equations of nonlocal elasticity, the displacement field equations coupled by van der Waals forces are derived. The set of governing equations of motion are then numerically solved by a novel method emerged from incorporating the radial point interpolation approximation within the framework of the generalized differential quadrature method. The present analysis provides the possibility of considering different combinations of layerwise boundary conditions. The influences of small scale factor, layerwise boundary conditions and geometrical parameters on the mechanical behavior of DWCNTs are fully investigated. Explicit expressions for the nonlocal frequencies of DWCNTs with all edges simply supported are also analytically obtained by a nonlocal elastic beam model. Some new intertube resonant frequencies and the corresponding noncoaxial vibrational modes are identified due to incorporating circumferential modes into the shell model. A shift in noncoaxial mode numbers, not predictable by the beam model, is also observed when the radius of DWCNTs is varied. The results generated also provide valuable information concerning the applicability of the beam model and new noncoaxial modes affecting the physical properties of nested nanotubes.
Peristaltic Flow of Pseudoplastic Fluid in a Curved Channel With Wall Properties
Authors: Hina S. , Mustafa M. , Hayat T. , Alsaedi A.
Published: August 2012

The effects of wall properties on the peristaltic flow of an incompressible pseudoplastic fluid in a curved channel are investigated. The relevant equations are modeled. Long wavelength and low Reynolds number approximations are adopted. The stream function and axial velocity are derived. The variations of the embedding parameters into the problem are carefully discussed. It is noted that the velocity profiles are not symmetric about the central line of the curved channel.
A Solid Shell Finite Element Formulation for Dielectric Elastomers
Authors: Klinkel Sven , Zwecker Sandro , Müller Ralf
Published: August 2012

This paper is concerned with a solid shell finite element formulation to simulate the behavior of thin dielectric elastomer structures. Dielectric elastomers belong to the group of electroactive polymers. Due to efficient electromechanical coupling and the huge actuation strain, they are very interesting for actuator applications. The coupling effect in the material is mainly caused by polarization. In the present work, a simple constitutive relation, which is based on an elastic model involving one additional material constant to describe the polarization state, is incorporated in a solid shell formulation. It is based on a mixed variational principle of Hu-Washizu type. Thus, for quasi-stationary fields, the balance of linear momentum and Gauss' law are fulfilled in a weak sense. As independent fields, the displacements, electric potential, strains, electric field, mechanical stresses, and dielectric displacements are employed. The element has eight nodes with four nodal degrees of freedom, three mechanical displacements, and the electric potential. The surface oriented shell element models the bottom and the top surfaces of a thin structure. This allows for a simple modeling of layered structures by stacking the elements through the thickness. Some examples are presented to demonstrate the ability of the proposed formulation.
Effects of the Longitudinal Surface Roughness on Fiber Pull-Out Behavior in Carbon Fiber-Reinforced Epoxy Resin Composites
Authors: Yao Yin , Chen Shaohua
Published: August 2012

Surface modifications are known as efficient technologies for advanced carbon fibers to achieve significant improvement of interface adhesion in composites, one of which is to increase the surface roughness in the fiber's longitudinal direction in practice. As a result, many microridges and grooves are produced on carbon fiber's surfaces. How does the surface roughness influence the carbon fiber's pull-out behavior? Are there any restrictions on the relation between the aspect ratio and surface roughness of fibers in order to obtain an optimal interface? Considering the real morphology on carbon fiber's surface, i.e., longitudinal roughness, an improved shear-lag theoretical model is developed in this paper in order to investigate the interface characteristics and fiber pull-out for carbon fiber-reinforced thermosetting epoxy resin (brittle) composites. Closed-form solutions to the carbon fiber stress are obtained as well as the analytical load-displacement relation during pullout, and the apparent interfacial shear strength (IFSS). It is found that the interfacial adhesion and the apparent IFSS are effectively strengthened and improved due to the surface roughness of carbon fibers. Under a given tensile load, an increasing roughness will result in a decreasing fiber stress in the debonded zone and a decreasing debonded length. Furthermore, it is interesting to find that, for a determined surface roughness, an optimal aspect ratio, about 30∼45, of carbon fibers exists, at which the apparent IFSS could achieve the maximum. Comparison to the existing experiments shows that the theoretical model is feasible and reasonable to predict the experimental results, and the theoretical results should have an instructive significance for practical designs of carbon/epoxy composites.
Measurement of stop consonant identification using adaptive tracking procedures
Authors: Liu Chang , Eddins David A.
Published: August 2012

The purpose of this study was to establish the potential utility of adaptive tracking procedures, relative to the method of constant stimuli, when examining consonant identification in cafeteria noise or four-talker babble. Thresholds for consonant identification were comparable for the two methods, while psychometric function slopes derived from the two methods were statistically different. To obtain accurate slope estimates from adaptive procedures, the target percent correct and change in variability with signal-to-noise ratio should be considered carefully. However, adaptive procedures are accurate and more efficient than the method of constant stimuli when the purpose is to estimate phoneme identification threshold.
Gamma-Ray Bursts
Authors: Gehrels Neil , Mészáros Péter
Published: August 2012

Stellar Explosions

Stars that are born with masses greater than eight times that of the Sun end their lives in luminous explosions known as supernovae. Over the past decade, access to improved sky surveys has revealed rare types of supernovae that are much more luminous than any of those that were known before.
Gal-Yam
(p.
927
) reviews these superluminous events and groups them into three classes that share common observational and physical characteristics. Gamma-ray bursts are another type of extreme explosive events related to the death of massive stars, which occur once per day somewhere in the universe and produce short-lived bursts of gamma-ray light.
Gehrels and Mészáros
(p.
932
) review what has been learned about these events since the launch of NASA's Swift (2004) and Fermi (2008) satellites. The current interpretation is that gamma-ray bursts are related to the formation of black holes. Type Ia supernovae are used as cosmological distance indicators. They are thought to be the result of the thermonuclear explosion of white dwarf stars in binary systems, but the nature of the stellar companion to the white dwarf is still debated.

Dilday
et al.

(p.
942
) report high-resolution spectroscopy of the supernova PTF 11kx, which was detected on 26 January 2011 by the Palomar Transient Factory survey. The data suggest a red giant star companion whose material got transferred to the white dwarf.
Absorption Features in the X-ray Spectrum of an Ordinary Radio Pulsar
Authors: Kargaltsev Oleg , Durant Martin , Misanovic Zdenka , Pavlov George G.
Published: August 2012

Finger on the Pulsar

Pulsars, the most commonly seen neutron stars, have been known for over four decades. They are rotating, dense stars with very strong magnetic fields, whose spectra have been understood as a superposition of continuum components of thermal and nonthermal origin.

Kargaltsev
et al.

(p.
946
) now report the detection of absorption features in the x-ray spectrum of an ordinary radio pulsar. These features may be more common than was previously thought and may provide the opportunity to probe the environment and radiation physics of neutron stars.
Toward a Lawful History of Life
Rereading the Fossil Record
The Growth of Paleobiology as an Evolutionary Discipline

by David Sepkoski

University of Chicago Press, Chicago, 2012. 400 pp. $55, £35.50. ISBN 9780226748559.
Authors: Beatty John
Published: August 2012

Drawing on archival material and interviews with principal participants, Sepkoski examines the rise of paleobiology—as a discipline and as an approach to understanding the history and processes of evolution on Earth.
A Long View on Climate Sensitivity
Authors: Skinner Luke
Published: August 2012

The paleoclimate record suggests that certain aspects of climate change may be difficult to reconcile with a single value of climate sensitivity.
Design of Stable Nanocrystalline Alloys
Authors: Chookajorn Tongjai , Murdoch Heather A. , Schuh Christopher A.
Published: August 2012

Metal Manipulation

Reducing the grain size below 100 micrometers can vastly improve the properties of a metal. However, these nanocrystalline metals are not thermally stable; at elevated temperatures the grains will grow and merge. Alloying with a second metal to slow grain growth can slow down this process, which has shown some success on a trial-and-error basis.

Chookajorn
et al.

(p.
951
; see the Perspective by

Weertman

) now provide a theoretical framework to create stability maps to identify potential alloys with the greatest thermal stability. For tungsten, counterintuitively, the theory suggests that atoms with the largest size differential or lowest solubility are not the best alloying choice. Indeed, an alloy of tungsten and titanium was processed more easily than pure nanocrystalline tungsten and also showed better stability at high temperatures.
Dense Chromatin Activates Polycomb Repressive Complex 2 to Regulate H3 Lysine 27 Methylation
Authors: Yuan Wen , Wu Tong , Fu Hang , Dai Chao , Wu Hui , Liu Nan , Li Xiang , Xu Mo , Zhang Zhuqiang , Niu Tianhui , Han Zhifu , Chai Jijie , Zhou Xianghong Jasmine , Gao Shaorong , Zhu Bing
Published: August 2012

Maintaining Repression

The Polycomb Repressive Complex 2 (PRC2) plays a critical role in gene silencing in metazoans, methylating histone H3 on lysine 27 (H3K27) to generate a repressive chromatin mark. The catalytic subunit E(z)/Ezh2 requires the presence of two other subunits—ESC/EED and Su(z)12—for enzyme activity.

Yuan
et al.

(p.
971
; see the Perspective by

Pirrotta

) show that both a fragment of the histone H3 N-terminal tail, and histone H1 stimulated PRC2 enzyme activity on poor, low-density chromatin substrates, indicating that that PRC2 is regulated by the density and compaction states of chromatin. The histone H3 fragment binds to the Su(z)12 subunit of PRC2 to stimulate E(z)/Ezh2. Local chromatin compaction preceded establishment of histone H3K27 methylation indicating how PRC2 might maintain the repressed state.
Sense, If Not Sensibility
Bird Sense
What It's Like to Be a Bird

by Tim Birkhead

Walker, New York, 2012. 288 pp. $25. ISBN 9780802779663. Bloomsbury, London. £16.99. ISBN 9781408820131.
Authors: Young Hillary S.
Published: August 2012

Birkhead mixes informative accounts of avian sensory systems with stories about the research that has developed our current knowledge of them.
Stepwise Evolution of Spherical Seeds into 20-Fold Twinned Icosahedra
Authors: Langille Mark R. , Zhang Jian , Personick Michelle L. , Li Shuyou , Mirkin Chad A.
Published: August 2012

Interrogating Growing Nanoparticles

Several methods can be used to follow the mechanistic steps of a chemical reaction, but the growth of a nanoparticle from a small seed crystal is more difficult to follow.

Langille
et al.

(p.
954
) used plasmonic gold nanocrystals of different shapes (cubes and octahedral) as seeds for the growth of larger silver nanoparticles. Electron microscopy was used to track the formation of several different particle shapes and internal structures during the growth process.
Water Security: Research Challenges and Opportunities
Authors: Bakker Karen
Published: August 2012

New strategies for analyzing water security have the potential to improve coordination and generate synergies between researchers, policy-makers, and practitioners.
Glycosylation to Adapt to Stress
Authors: Mattaini Katherine R. , Vander Heiden Matthew G.
Published: August 2012

Cancer cells may cope with oxidative stress through the glycosylation of a metabolic enzyme.
How to Read the Chromatin Past
Authors: Pirrotta Vincenzo
Published: August 2012

Several mechanisms are used by cells to maintain specific histone modifications and gene activity through successive cell divisions.
A New Dawn for Science in Africa
Authors: Maartens Roy , Ellis George
Published: August 2012

To Revolutionize Radio Astronomy, the International Square Kilometre Array (SKA) project (
www.skatelescope.org
) has a visionary plan for a $2 billion telescope network, and much of it will be based in Africa. For the first time, the continent will host the world's largest scientific instrument, symbolizing the importance of science and technology for Africa's future.
Panel Says NSF Should Shutter Six U.S. Instruments
Authors: Bhattacharjee Yudhijit
Published: August 2012

Recommendations from an NSF panel asked to find ways to cope with the agency's dismal budgetary outlook have researchers bracing for the potential shutdown of telescopes.
Dinosaur Kingpin Opens Fossil Bonanza to Science
Authors: Stone Richard
Published: August 2012

Zheng Xiaoting has single-handedly built one of the most important fossil collections in the world. This treasure in the Chinese countryside is beginning to draw paleontologists from near and far.
New Method Puts Elusive Indo-European Homeland in Anatolia
Authors: Pringle Heather
Published: August 2012

Evolutionary psychologists report in this week's issue that they have found decisive support for the Anatolian hypothesis of the origins of the Indo-European family of languages.
The Great Guppy Experiment
Authors: Pennisi Elizabeth
Published: August 2012

A tiny fish is showing how ecological and evolutionary forces interact to shape the world we live in.
Eco-Evo Effects Up and Down the Food Chain
Authors: Pennisi Elizabeth
Published: August 2012

Researchers are investigating how the alewife, a fish that lives in lakes in eastern North America, shapes and is shaped by its freshwater ecosystem.
Economic Crisis Forces Spanish Archaeology to Rethink Its Roots
Authors: Pain Elisabeth
Published: August 2012

After riding high for a decade, commercial archaeology in Spain faces a crisis in the wake of a real estate and economic bust.