Parents need to protect: influences, risks and tensions for parents of prepubertal children born with ambiguous genitalia.

Science.gov (United States)

Sanders, Caroline; Carter, Bernie; Goodacre, Lynne

2012-11-01

The aim of the study was to explore parents' experiences of and the influences, risks and tensions associated with their child's genital ambiguity and the place reconstructive surgeries had in their lives. Research into the clinical management of disorders of sex development is a complex and growing field of study. A small number of studies have indicated that the decisions parents make with regard to their child's care during infancy are confounded by moral, social and emotional factors which can influence their choices. Narrative methods. In-depth interviews elicited stories from 10 mothers and five fathers of 11 prepubertal children. A key theme from the data focused on the parents' motivations to protect their child from the real or perceived threats arising from other people's attitudes and responses to their ambiguous genitalia. Several rationales for their protective behaviours were described, which encouraged the parents to actively manage their child's care. The dilemmas that parents face in the complex and challenging situation following the birth of a child with ambiguous genitalia require early support from insightful professionals such as nurses. This support could better prepare the parents to recognise and discuss their protective behaviours and the impact these may have on their child's future. These findings draw attention to the parents' need for nurses to be knowledgeable about the impact that disorders of sex development can have on family's emotional, psychosocial well-being and decision-making. Nurses' awareness of the debate surrounding genital surgeries is important if they are to understand the motivations that underpin parents' decision-making and how to support them sensitively. Nurses are the health professionals who have the most consistent direct contact with these families throughout the child's life and, therefore, can provide support in the ongoing decision-making process. © 2012 Blackwell Publishing Ltd.

Elephantiasis of the external genitalia: A sequel to cutaneous tuberculosis

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Padmavathy L

2009-01-01

Full Text Available Tuberculosis continues to be an important public health problem and cutaneous tuberculosis constitutes a minor proportion of extra pulmonary manifestations of tuberculosis. Elephantiasis of the external genitalia, as a sequel to cutaneous tuberculosis, in a 40-year-old diabetic lady is being reported for its rarity. The patient also had lesions of healed scrofuloderma of 27 years′ duration, in both axillae, with residual pedunculated nodules.

Maternal exposure to procymidone has no effects on fetal external genitalia development in male rabbit fetuses in a modified developmental toxicity study.

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Inawaka, Kunifumi; Kishimoto, Noriyuki; Higuchi, Hashihiro; Kawamura, Satoshi

2010-06-01

This study was conducted to evaluate the effects of procymidone (PCM) on development of male rabbit fetal external genitalia. PCM was administered once daily by gavage at dose levels of 0 (control) and 125mg/kg/day to pregnant rabbits from gestation day 6 through 28 and fetal external genitalia was observed in detail. This treatment period covered the critical stage of sexual differentiation of fetal external genitalia in rabbits. In the maternal animals, food consumption was reduced in the PCM group. There were no effects of PCM on maternal caesarean sectioning data or fetal external observations. In fetal external genitalia observations, there were no significant differences between the control and PCM treatment group in any of the following parameters: ano-genital distance (AGD), phallus boundary-genital distance, diameter of preputial lamella, ventral gap of preputial lamella, or ventral gap to diameter ration of preputial lamella, though severe feminization such as decreasing of AGD and hypospadias in male rat offspring at the dose level of 125 mg/kg of PCM were reported. These results suggest that PCM has no effect on fetal external genitalia development in male rabbit fetuses, and species difference of developmental effects of PCM on sexual differentiation exists.

Ambiguous Genitalia

Science.gov (United States)

... hormone). • Gonads: reproductive organs (testicles and ovaries). At puberty, the testicle makes sperm and male hormones. The ovary releases eggs and female hormones. • Genitals: external sex organs, such as the penis and scrotum in males, and the clitoris and ...

Fetal sexing by ultrasonography identifying the genital tubercle or external genitalia of american alpine goats

International Nuclear Information System (INIS)

Santos, M.H.B. dos; Morae, E.P.B.X. de; Aguiar Filho, C.R. de; Chaves, R. de M.; Neves, J.P.; Lima, P.F. de; Oliveira, M.A.L. de

2007-01-01

The aim of this study was to diagnostic previously the gender of American Alpine fetuses by ultrasonography identifying the final position of the genital tubercle (GT) or viewing the anatomical structures of external genitalia, as well as to evaluate the accuracy of fetal sexing by single or repeated exams. In Group I (GI), the gender was defined by the final position of the GT and in Group II (GII) by the anatomical structures of external genitalia. The examinations were carried out with an ultrasound device by via transrectal equipped with a linear transducer with 6.0 and 8.0 MHz. In GI, 52 fetuses of 32 goats were monitored each 12 hours, from 40th to the 60th day of pregnancy. In GII, the examination was performed only once in 34 fetuses of 24 goats with pregnancy between 45 and 70 days. The accuracy in GI was 100% in single, 87.5% in twin and 66.7% in triple pregnancy, with significant difference (P 0.05) between single and twin pregnancies. The final migration of GT occured on the 46.4 ± 2.1 days of pregnancy. The results allow to conclude that ultrasonography is a suitable method to early diagnostic the fetal sex by visualization of final position of GT or by identification of external genitalia structures and that repeated exams did not increase the accuracy of fetal sexing on the multiple pregnancy [pt

De morseir syndrome presenting as ambiguous genitalia

OpenAIRE

Anubhav Thukral; S Chitra; Partho P Chakraborty; Ajitesh Roy; Soumik Goswami; Rana Bhattacharjee; Deep Dutta; Indira Maisnam; Sujoy Ghosh; Satinath Mukherjee; Subhankar Chowdhury

2012-01-01

Background: A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. Materials and Methods: The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficie...

De morseir syndrome presenting as ambiguous genitalia

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Anubhav Thukral

2012-01-01

Full Text Available Background: A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. Materials and Methods: The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficient as suggested by auxology, low IGF1, and poor response to clonidine stimulation. MRI brain shows hypoplastic corpus callosum, hypoplastic anterior pituitary, and ectopic posterior pituitary bright spot. Results: The patient underwent laparoscopic removal of right intrabdominal testis and orchidoplexy was performed on the left one. Testicular biopsy revealed no malignancy and growth hormone replacement was initiated. The patient awaits definitive repair of hypospadias. Conclusion: As a provisional diagnosis of combined growth hormone and gonadotropin deficiency, most probable diagnosis is septo-optic dysplasia or de moseir syndrome leading to genital ambiguity.

De morseir syndrome presenting as ambiguous genitalia.

Science.gov (United States)

Thukral, Anubhav; Chitra, S; Chakraborty, Partho P; Roy, Ajitesh; Goswami, Soumik; Bhattacharjee, Rana; Dutta, Deep; Maisnam, Indira; Ghosh, Sujoy; Mukherjee, Satinath; Chowdhury, Subhankar

2012-12-01

A 10-year-old boy presented with genital ambiguity, poor linear growth, and delayed milestones. The aim and to highlight that although rare but congenital, hypogonadotropic hypogonadism may rarely present as ambiguity. The patient was found to have bilateral cryptorchidism with proximal penile hypospadias, microphallus with a proportionate dwarfism with mildly delayed bone age, and karyotype 46XY. Euthyroid with normal steroid axis, growth hormone insufficient as suggested by auxology, low IGF1, and poor response to clonidine stimulation. MRI brain shows hypoplastic corpus callosum, hypoplastic anterior pituitary, and ectopic posterior pituitary bright spot. The patient underwent laparoscopic removal of right intrabdominal testis and orchidoplexy was performed on the left one. Testicular biopsy revealed no malignancy and growth hormone replacement was initiated. The patient awaits definitive repair of hypospadias. As a provisional diagnosis of combined growth hormone and gonadotropin deficiency, most probable diagnosis is septo-optic dysplasia or de moseir syndrome leading to genital ambiguity.

Bacterial and fungal microflora on the external genitalia of male donkeys (Equus asinus).

Science.gov (United States)

Carleton, Carla L; Donahue, J Michael; Marteniuk, Judith V; Sells, Stephen F; Timoney, Peter J

2015-02-01

This study was undertaken to investigate the bacterial and fungal microflora on the external genitalia of a population of healthy male donkeys in the state of Michigan, USA. The aim was to identify and determine the frequency of occurrence of these microorganisms using seven different isolation media and standard microbiological procedures. The sites (urethral fossa [fossa glandis], dorsal diverticulum of the urethral sinus, distal urethra, and penile surface) in the distal reproductive tract were cultured and each isolated microorganism identified. Ten different genera of gram-positive bacteria, eight different genera of gram-negative bacteria, and two genera of fungi were isolated from the external genitalia of the 43 donkeys in this study. All 43 donkeys yielded gram-positive bacteria (2-8 species) from all four sites sampled. Arcanobacterium spp., Corynebacterium spp., and Bacillus spp. were the most frequently isolated gram-positive bacteria. Gram-negative bacteria were cultured from 16 (37.2%) of the 43 donkeys, with Acinetobacterlwoffii (16.3%), Oligella urethralis (11.6%), and Taylorellaasinigenitalis (9.3%), the most frequently isolated. Fungi were cultured from only 5 (11.6%) of the 43 donkeys, with Rhizopus spp. isolated from 3 (7.0%) and Cladosporium spp. from 2 (4.7%) individuals. The testes and epididymides collected from 40 donkeys at time of castration were culture negative. Few differences were found in the bacterial flora between prepubertal and mature intact and castrated donkeys. Of notable interest was the scarcity of known equine pathogens across the population tested and isolation of T. asinigenitalis from normal donkeys, especially prepubertal individuals and previously castrated males. Copyright © 2014 Elsevier B.V. All rights reserved.

Subcutaneous emphysema, pneumomediastinum, pneumothorax, pneumoperitoneum, and pneumoretroperitoneum by insufflation of compressed air at the external genitalia in a child.

Science.gov (United States)

Muramori, Katsumi; Takahashi, Yukiko; Handa, Noritoshi; Aikawa, Hisayuki

2009-04-01

A 7-year-old girl with concurrent subcutaneous emphysema, pneumomediastinum, pneumothorax, pneumoperitoneum, and pneumoretroperitoneum arrived at our facility. Compressed air at 5 atm of pressure was insufflated through the nozzle of a spray gun over her external genitalia. She was admitted for a small amount of genital bleeding and significant subcutaneous emphysema extending from the cheek to the upper body. Radiographic examination of the abdomen was suggestive of a visceral perforation, but she was managed conservatively and discharged in satisfactory condition without surgical intervention. The female genitalia possibly served as the entry point for air into the retroperitoneum and peritoneal cavity, with subsequent migration of air through the esophageal hiatus that resulted in pneumomediastinum, pneumothorax, and extensive subcutaneous emphysema.

Congenital lymphoedema of the genitalia

NARCIS (Netherlands)

Bolt, R. J.; Peelen, W.; Nikkels, P. G.; de Jong, T. P.

1998-01-01

Isolated congenital lymphoedema of the external genitalia in boys is extremely rare. It can have major physical and emotional consequences for the children. Three male patients with primary lymphoedema of the penis and scrotum are described. The first case presented with lymphoedema of the prepuce

Ultra Morphological Structure of Sensory Sensillae on the Legs and External Genitalia of the Red Palm Weevil Rhynchophorus ferrugineus (Oliv.)

International Nuclear Information System (INIS)

Sharaby, Aziz M.; AlDosary, Mona M.

2007-01-01

The Red Palm Weevil (RPW) is a major pest infesting date trees in the Gulf region. Chemoreceptors play an important role for insects behaviour in detecting their defined host for feeding, egg laying or mating. The present study is aimed to study morphological structure of sensillae on different legs and external genitalia of both sexes. Three kinds of sensillae are found on the different parts of the three pairs of fore, mid and hind legs, these sensillae are identified as ( Trichoid in three types, coeloconic in two types and one type of Basiconic sensillae). Fore legs bear the highest number of different forms of sensillae, males contained realatively greater number than females. Mid femur only in female bears a dense hair of trichoid sensillae, while they are found on fore- mid and hind femur of males, this may be used for differentiating two sexes. Female ovipositor contained trichoid sensilla can be subdivided into three distinct type1,2, and 3 in addition placoid sensillae, it could be identified four types of trichoid sensilla on the male external genitalia and numerous of placoid sensillae.These may be for hygroreception. (author)

Securing Paternity by Mutilating Female Genitalia in Spiders.

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Mouginot, Pierick; Prügel, Josepha; Thom, Ulrike; Steinhoff, Philip O M; Kupryjanowicz, Janusz; Uhl, Gabriele

2015-11-16

Competition between males and their sperm over access to females and their eggs has resulted in manifold ways by which males try to secure paternity, ranging from physically guarding the female after mating to reducing her receptivity or her attractiveness to subsequent males by transferring manipulative substances or by mechanically sealing the female reproductive tract with a copulatory plug. Copulations may also result in internal damage of the female genitalia; however, this is not considered as a direct adaptation against sperm competition but as a collateral effect. Here, we present a drastic and direct mechanism for securing paternity: the removal of coupling structures on female genitalia by males. In the orb-weaving spider Larinia jeskovi males remove the scapus, a crucial coupling device on the female external genital region. Reconstruction of the coupling mechanism using micro-CT-scanned mating pairs revealed that several sclerites of the male genitalia interact to break off the scapus. Once it is removed, remating cannot occur due to mechanical coupling difficulties. In the field, male-inflicted genital damage is very prevalent since all female L. jeskovi were found to be mutilated at the end of the mating season. External genital mutilation is an overlooked but widely spread phenomenon since 80 additional spider species were found for which male genital manipulation can be suspected. Interlocking genitalia provide an evolutionary platform for the rapid evolution of this highly effective mechanism to secure paternity, and we suspect that other animal groups with interlocking genital structures might reveal similarly drastic male adaptations. Copyright © 2015 Elsevier Ltd. All rights reserved.

The management of dog bite injuries of genitalia in paediatric age

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Mirko Bertozzi

2013-01-01

Full Text Available Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also directly related to the severity of initial wound. Guidelines for the management of dog bites include irrigation, dιbridment, antibiotic therapy, consideration of tetanus and rabies immunisation and suture of wounds or surgical reconstruction. Literature review was conducted and focused to analyze the management of dog bite lesions involving external genitalia.

Ambigüidade genital: a percepção da doença e os anseios dos pais Ambiguous genitalia: perception of the disease and parents anxiety

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Carlos Antonio Bruno da Silva

2006-03-01

anguish noted in the neonatal period are expressed by the fear of death, incurable disease and medication. During childhood, of the surgical procedure (ambiguous genitalia and sexuality (homosexuality. During puberty and adulthood there's the fear of marginalization, prejudice, homosexuality and infertility. There is anguish related to pointing at the guilty party, sexual definition (ambiguity and the need for secrecy. CONCLUSIONS: ambiguous genitalia is a highly complex condition affecting the family psychological balance. In situations of genital ambiguity determining and demystifying fears and expectations should be part of the therapeutic plan.

Female nurses' sensitivity to male genitalia-related care in mainland China.

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Zang, Yu-Li; Chung, Loretta Y F; Wong, Thomas K S; Chan, Moon Fai

2012-02-01

To discover the latent psychosocial construct of female nurses' sensitivity to male genitalia-related care in the context of sexual conservativeness. Many nursing activities involve direct exposure or contact with male external genitalia. In the sexually conservative culture and the predominance of female nurses, this area is the subject of continuing interest and investigation. Methodological research design. An item pool related to male genitalia-related care was generated through a panel of experts and then reduced to a short form questionnaire, the Female Nurses' Sensitivity to Male Genitalia Related Care scale. Using data from a purposive sample of 588 female nurses, the structure of the questionnaire was examined using structural equation modelling. The validity was examined against existing scales. The 13-item Female Nurses' Sensitivity to Male Genitalia Related Care scale has a two-factor structure with high internal consistency (α = 0·87) and test-retest reliability of 0·90. Nearly all model fit measures reach the criteria of being an acceptable model fit except chi-squared statistics. Scores on Female Nurses' Sensitivity to Male Genitalia Related Care can be best predicted by that of brief Fear of Negative Evaluation Scale, Embarrassability Scale and Situational Susceptibility to Embarrassment Scale. The anxiety of projecting a positive image and the pursuit of sexual propriety may underpin female nurses' sensitivity to male genitalia-related care. This trait can be measured by the 13-item female nurses' sensitivity-male genitalia-related care scale with satisfactory psychometric properties including internal consistency, reliability, content validity and construct validity. Particular attention shall be paid to the negative effects of social rules or norms including sexual propriety rules over (female) nurses' perceptions, attitudes and behaviours. Strengthening nursing education in this regard is important to overcome negative effects on female

Physical examination of the female internal and external genitalia with and without pelvic organ prolapse: A review.

Science.gov (United States)

Pahwa, Avita K; Siegelman, Evan S; Arya, Lily A

2015-04-01

Pelvic organ prolapse, a herniation of pelvic organs through the vagina, is a common condition in older women. Pelvic organ prolapse distorts vaginal anatomy making pelvic examination difficult. A clinician must accurately identify anatomic landmarks both in women presenting with symptoms of prolapse and in women noted to have coincidental prolapse during routine gynecologic examination. We present a systematic approach to the female pelvic examination including anatomic landmarks of the external genitalia, vagina, and uterus in women with normal support as well as changes that occur with pelvic organ prolapse. Knowledge and awareness of normal anatomic landmarks will improve a clinician's ability to identify defects in pelvic support and allow for better diagnosis and treatment of pelvic organ prolapse. © 2014 Wiley Periodicals, Inc.

Distinct copulation positions in Drosophila pachea males with symmetric or asymmetric external genitalia

NARCIS (Netherlands)

Lang, M.; Orgogozo, V.

2012-01-01

Left-right asymmetric genitalia have appeared multiple times independently in insects and have been associated with changes in mating positions. However, there is little experimental data on how the evolution of genital asymmetries may have affected the evolution of mating positions or vice versa.

The management of dog bite injuries of genitalia in paediatric age ...

African Journals Online (AJOL)

Dog bite injuries are common in children and represent an important health-care problem. Most dog bite injuries involve the face or an extremity. Victims tend to seek medical care quickly. Dog bites to the external genitalia are rarely reported, but they potentially result in morbidity if improperly managed. Morbidity is also ...

Distinct copulation positions in Drosophila pachea males with symmetric or asymmetric external genitalia: erratum

NARCIS (Netherlands)

Lang, M.; Orgogozo, V.

2016-01-01

Left-right asymmetric genitalia have appeared multiple times independently in insects and have been associated with changes in mating positions. However, there is little experimental data on how the evolution of genital asymmetries may have affected the evolution of mating positions or vice versa.

A t(5;16) translocation is the likely driver of a syndrome with ambiguous genitalia, facial dysmorphism, intellectual disability, and speech delay.

Science.gov (United States)

Ozantürk, Ayşegül; Davis, Erica E; Sabo, Aniko; Weiss, Marjan M; Muzny, Donna; Dugan-Perez, Shannon; Sistermans, Erik A; Gibbs, Richard A; Özgül, Köksal R; Yalnızoglu, Dilek; Serdaroglu, Esra; Dursun, Ali; Katsanis, Nicholas

2016-03-01

Genetic studies grounded on monogenic paradigms have accelerated both gene discovery and molecular diagnosis. At the same time, complex genomic rearrangements are also appreciated as potent drivers of disease pathology. Here, we report two male siblings with a dysmorphic face, ambiguous genitalia, intellectual disability, and speech delay. Through quad-based whole-exome sequencing and concomitant molecular cytogenetic testing, we identified two copy-number variants (CNVs) in both affected individuals likely arising from a balanced translocation: a 13.5-Mb duplication on Chromosome 16 (16q23.1 → 16qter) and a 7.7-Mb deletion on Chromosome 5 (5p15.31 → 5pter), as well as a hemizygous missense variant in CXorf36 (also known as DIA1R). The 5p terminal deletion has been associated previously with speech delay, whereas craniofacial dysmorphia and genital/urinary anomalies have been reported in patients with a terminal duplication of 16q. However, dosage changes in either genomic region alone could not account for the overall clinical presentation in our family; functional testing of CXorf36 in zebrafish did not induce defects in neurogenesis or the craniofacial skeleton. Notably, literature and database analysis revealed a similar dosage disruption in two siblings with extensive phenotypic overlap with our patients. Taken together, our data suggest that dosage perturbation of genes within the two chromosomal regions likely drives the syndromic manifestations of our patients and highlight how multiple genetic lesions can contribute to complex clinical pathologies.

Aesthetic surgery of the male genitalia.

Science.gov (United States)

Alter, Gary J; Salgado, Christopher J; Chim, Harvey

2011-08-01

Appearance of the male genitalia is linked with self-esteem and sexual identity. Aesthetic surgery of the male genitalia serves to correct perceived deficiencies as well as physical deformities, which may cause psychological distress. Attention to patient motivation for surgery and to surgical technique is key to achieving optimal results. In this review, the authors describe aesthetic surgical techniques for treatment of penile and scrotal deficiencies. They also discuss techniques for revision in patients with previous surgery.

PERILAKU PERSONAL HYGIENE GENITALIA SANTRIWATI DI PESANTREN UMMUL MUKMININ MAKASSAR SULAWESI SELATAN

OpenAIRE

Sandriana; Ibnu, Indra Fajarwati; Rachman, Watief A.

2015-01-01

Salah satu akibat kurangnya pemahaman personal hygiene genitalia yaitu terjadinya gangguan kesehatan organ reproduksi seperti keputihan, infeksi saluran kemih (ISK), penyakit radang panggul (PRP) dan kemungkinan terjadi kanker leher rahim sehingga dibutuhkan pemahaman yang baik mengenai personal hygiene genitalia pada remaja agar dapat terhindar dari ancaman penyakit reproduksi. Studi kualitatif dengan rancangan fenomenologi dilakukan untuk mengetahui perilaku personal hygiene genitalia santr...

Condition-dependent female preference for male genitalia length is based on male reproductive tactics.

Science.gov (United States)

Hernandez-Jimenez, Armando; Rios-Cardenas, Oscar

2017-12-06

There is extensive morphological variation of male genitalia across animals with internal fertilization, even among closely related species. Most studies attempting to explain this extraordinary diversity have focused on processes that occur post-copula (e.g. sperm competition, cryptic female choice). Only a few studies have focused on the pre-copula process of female preference. In addition, the extent to which this variation could be associated with the use of different reproductive tactics has yet to be explored. Here, we show that female preference for male genitalia length in two livebearing fishes depends on the type of reproductive tactic of the males being evaluated as well as the body condition of the female. In a species where all males coax females to acquire matings (courters), females preferred males with short genitalia. In a species with genetically influenced alternative reproductive tactics (courter males that only court and produce courter sons, sneaker males that use the coercive tactic of sneak chase and produce sneaker sons), female preference depended on an interaction between male tactic and female condition: females in good condition preferred courter males with short genitalia, and sneaker males with long genitalia. Our results suggest that female preference for male traits favourable to their sons may be an important factor contributing to the diversification of male genitalia. Despite the contrasting selection for genitalia length that our female preference tests suggest, we found no significant differences in genitalia length between coaxing (courters) and coercive (sneakers) males. Our study represents a starting point to more clearly understand the role of alternative reproductive tactics and variation in female mate preference in the evolution of male genitalia. © 2017 The Author(s).

408 Cases of Genital Ambiguity Followed by Single Multidisciplinary Team during 23 Years: Etiologic Diagnosis and Sex of Rearing

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Georgette Beatriz De Paula

2016-01-01

Full Text Available Objective. To evaluate diagnosis, age of referral, karyotype, and sex of rearing of cases with disorders of sex development (DSD with ambiguous genitalia. Methods. Retrospective study during 23 years at outpatient clinic of a referral center. Results. There were 408 cases; 250 (61.3% were 46,XY and 124 (30.4% 46,XX and 34 (8.3% had sex chromosomes abnormalities. 189 (46.3% had 46,XY testicular DSD, 105 (25.7% 46,XX ovarian DSD, 95 (23.3% disorders of gonadal development (DGD, and 19 (4.7% complex malformations. The main etiology of 46,XX ovarian DSD was salt-wasting 21-hydroxylase deficiency. In 46,XX and 46,XY groups, other malformations were observed. In the DGD group, 46,XY partial gonadal dysgenesis, mixed gonadal dysgenesis, and ovotesticular DSD were more frequent. Low birth weight was observed in 42 cases of idiopathic 46,XY testicular DSD. The average age at diagnosis was 31.7 months. The final sex of rearing was male in 238 cases and female in 170. Only 6.6% (27 cases needed sex reassignment. Conclusions. In this large DSD sample with ambiguous genitalia, the 46,XY karyotype was the most frequent; in turn, congenital adrenal hyperplasia was the most frequent etiology. Malformations associated with DSD were common in all groups and low birth weight was associated with idiopathic 46,XY testicular DSD.

Rapid diversification of male genitalia and mating strategies in Ohomopterus ground beetles.

Science.gov (United States)

Takami, Y; Sota, T

2007-07-01

We analysed evolutionary diversification and covariation in male genitalia and four mating traits related to sexual selection, i.e. testis size, spermatophore size, copulation duration and post-copulatory guarding duration, in Ohomopterus ground beetles using phylogenetically independent contrasts. Male genital size and mating duration have evolved more rapidly than body size and the other traits studied. Male genital size was negatively correlated with copulation duration, suggesting that elongated male genitalia may enable decreased time investment in a single copulation because it is more effective at facilitating spermatophore deposition. Male genital size was positively correlated with spermatophore size, suggesting coevolution between offensive and defensive male mating tactics because the elongated male genitalia may be advantageous in displacement of rivals' plug-like spermatophores, and decreased mating duration may intensify sperm competition. Thus, the remarkable diversity of male genitalia in Ohomopterus may have been facilitated by the interplay between inter- and intrasexual selection processes.

Labia Majora Augmentation Combined With Minimal Labia Minora Resection: A Safe and Global Approach to the External Female Genitalia.

Science.gov (United States)

Hersant, Barbara; Jabbour, Samer; Noel, Warren; Benadiba, Laurent; La Padula, Simone; SidAhmed-Mezi, Mounia; Meningaud, Jean Paul

2018-04-01

All the labia minora reduction techniques fail to treat the other component of the abnormally increased labia minora to majora ratio: the labia majora atrophy. The purpose of this study is to describe a technique of female genitalia beautification, which combines labia majora augmentation and conservative labia minora reduction. The hypertrophied labia minora were first treated by a conservative inferior wedge excision with a superior flap. The conservative excision was done to obtain labia minora that would still protrude beyond the labia majora because it will be masked by the augmentation of the labia majora. Labia majora augmentation was done by autologous fat transplantation. The newly augmented labia majora completely masked the conservatively reduced labia minora. Twenty-one patients underwent surgery for labia majora augmentation and labia minora reduction. One patient (4.7%) had a small separation of the labial edge postoperatively that resolved with no additional interventions. There was no flap necrosis or infections. No patient reported pain or sexual dysfunction. Seventeen patients (81%) were satisfied or very satisfied with their results. Labia majora augmentation combined with a conservative labia minora reduction is an appealing procedure because it enhances the global aspect of the female genitalia while reducing the labioplasty complications.

Renormalization ambiguities and conformal anomaly in metric-scalar backgrounds

International Nuclear Information System (INIS)

Asorey, M.; Berredo-Peixoto, G. de; Shapiro, I. L.

2006-01-01

We analyze the problem of the existing ambiguities in the conformal anomaly in theories with an external scalar field in curved backgrounds. In particular, we consider the anomaly of a self-interacting massive scalar field theory and of a Yukawa model in the massless conformal limit. In all cases the ambiguities are related to finite renormalizations of local nonminimal terms in the effective action. We point out the generic nature of this phenomenon and provide a general method to identify the theories where such an ambiguity can arise

Blunted Ambiguity Aversion During Cost-Benefit Decisions in Antisocial Individuals.

Science.gov (United States)

Buckholtz, Joshua W; Karmarkar, Uma; Ye, Shengxuan; Brennan, Grace M; Baskin-Sommers, Arielle

2017-05-17

Antisocial behavior is often assumed to reflect aberrant risk processing. However, many of the most significant forms of antisocial behavior, including crime, reflect the outcomes of decisions made under conditions of ambiguity rather than risk. While risk and ambiguity are formally distinct and experimentally dissociable, little is known about ambiguity sensitivity in individuals who engage in chronic antisocial behavior. We used a financial decision-making task in a high-risk community-based sample to test for associations between sensitivity to ambiguity, antisocial behavior, and arrest history. Sensitivity to ambiguity was lower in individuals who met diagnostic criteria for Antisocial Personality Disorder. Lower ambiguity sensitivity was also associated with higher externalizing (but not psychopathy) scores, and with higher levels of aggression (but not rule-breaking). Finally, blunted sensitivity to ambiguity also predicted a greater frequency of arrests. Together, these data suggest that alterations in cost-benefit decision-making under conditions of ambiguity may promote antisocial behavior.

Ultrastructure of male genitalia of blow flies (Diptera: Calliphoridae) of forensic importance.

Science.gov (United States)

Sontigun, Narin; Sanit, Sangob; Wannasan, Anchalee; Sukontason, Kom; Amendt, Jens; Yasanga, Tippawan; Sukontason, Kabkaew L

2018-03-01

Male genitalia of blow flies (Diptera: Calliphoridae) are distinctive in their morphological features and are often used for species identification. The aim of this work was to investigate the male genitalia of blow flies of medical and forensic importance from Thailand at the ultrastructural level, using scanning electron microscopy (SEM). Flies in two subfamilies were examined: Chrysomyinae [Chrysomya bezziana Villeneuve, Chrysomya chani Kurahashi, Chrysomya nigripes Aubertin, Chrysomya pinguis (Walker), Chrysomya rufifacies (Macquart), Chrysomya thanomthini Kurahashi & Tumrasvin, and Chrysomya villeneuvi Patton] and Luciliinae [Hemipyrellia ligurriens (Wiedemann), Hypopygiopsis infumata (Bigot), Hypopygiopsis tumrasvini Kurahashi, Lucilia cuprina (Wiedemann), Lucilia papuensis Macquart, Lucilia porphyrina (Walker), and Lucilia sinensis Aubertin]. Particular attention was paid to the main distinguishing features such as the shapes of the cercus and the surstylus, and the complex structure of the distiphallus. The differentiation of the male genitalia of these species at the SEM level is discussed and compared to the conditions in closely related species such as Chrysomya megacephala (Fabricius). A key for the identification of 14 blow fly species based on male genitalia is provided. Copyright © 2017 Elsevier B.V. All rights reserved.

A Newborn with Genital Ambiguity, 45,X/46,XY Mosaicism, a Jumping Chromosome Y, and Congenital Adrenal Hyperplasia

Directory of Open Access Journals (Sweden)

Lei Zhang

2013-01-01

Full Text Available Disorders of sex development (DSD, formerly termed “intersex” conditions, arise from numerous causes. CAH secondary to 21-hydroxylase deficiency is the most common cause of DSD. Sex chromosome disorders, including sex chromosome mosaicism, are the second most common cause of DSD. We discuss a medically complex neonate with DSD presenting with ambiguous genitalia. Hormone levels suggested 21-hydroxylase deficiency. Molecular analysis revealed compound heterozygous mutations in the 21-hydroxylase gene (CYP21A2, confirming the diagnosis of CAH. Chromosome analysis revealed sex chromosome mosaicism with three cell lines: 45,X[8]/45,X,tas(Y;16(p11.32;p13.3[8]/45,X,t(Y;8(p11.32;p23.3[4] with the Y chromosome in telomere association with chromosomes 8p and 16p in different cell lines, a “jumping translocation.” Histologically, the right gonad had irregular, distended seminiferous tubules with hyperplastic germ cells contiguous with ovarian stroma and primordial follicles. The left gonad had scant ovarian stroma and embryonic remnants. Chromosome analyses showed mosaicism in both gonads: 45,X[17]/45,X,tas(Y;8(p11.32;p23.3[3]. This is the first case of coexisting CAH and 45,X/46,XY mosaicism reported in the English literature and the third case of a constitutional chromosome Y “jumping translocation.” Our report documents the medical and genetic complexity of children such as this one with ambiguous genitalia and discusses the need for a multidisciplinary team approach.

Ambiguity

DEFF Research Database (Denmark)

Stein, Mari-Klara; Jensen, Tina Blegind

Digitalization is changing the nature of work in knowledge professions in significant ways. One of the oft-observed, yet poorly understood, consequences of work digitalization in this context is increased ambiguity, frequently captured under the notion of blurred boundaries and paradoxes. While...... the introduction of ICTs is often credited with the potential to bring about ambiguity in a work context, we lack an in-depth understanding of how and why digitalization can introduce ambiguity, and what ambiguity actually means in this context. In this paper, we aim to further our current theorization...... of ambiguity in ICT-enabled work in knowledge professions. We offer a conceptual clarification of three related issues: (1) why does digitalization introduce ambiguity, (2) what kinds of ambiguities digitalization introduces, and (3) how workers act upon ambiguity....

Ambiguous Belonging and the Challenge of Inclusion: Parent Perspectives on School Membership

Science.gov (United States)

Scorgie, Kate

2015-01-01

Boundary ambiguity occurs when members of a family are confused or uncertain regarding roles, responsibilities and subsystem configurations within the family. Research suggests that perception of boundary ambiguity is associated with family stress despite internal and external resource availability. It has been suggested that research on family…

The 5 Alpha-Reductase Isozyme Family: A Review of Basic Biology and Their Role in Human Diseases

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Faris Azzouni

2012-01-01

Full Text Available Despite the discovery of 5 alpha-reduction as an enzymatic step in steroid metabolism in 1951, and the discovery that dihydrotestosterone is more potent than testosterone in 1968, the significance of 5 alpha-reduced steroids in human diseases was not appreciated until the discovery of 5 alpha-reductase type 2 deficiency in 1974. Affected males are born with ambiguous external genitalia, despite normal internal genitalia. The prostate is hypoplastic, nonpalpable on rectal examination and approximately 1/10th the size of age-matched normal glands. Benign prostate hyperplasia or prostate cancer does not develop in these patients. At puberty, the external genitalia virilize partially, however, secondary sexual hair remains sparse and male pattern baldness and acne develop rarely. Several compounds have been developed to inhibit the 5 alpha-reductase isozymes and they play an important role in the prevention and treatment of many common diseases. This review describes the basic biochemical properties, functions, tissue distribution, chromosomal location, and clinical significance of the 5 alpha-reductase isozyme family.

External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

International Nuclear Information System (INIS)

Hoennicke, M.G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L.A.; Rosado-Neto, G.H.

2010-01-01

Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

Ambiguity and risk measures in the lab and students’ real-life borrowing behavior

NARCIS (Netherlands)

Fairley, Kim; Weitzel, Utz

This study analyzes the external validity of experimentally elicited ambiguity aversion, likelihood insensitivity and risk aversion on real-life decision-making in the field of student loans. Our main finding is that ambiguity aversion, likelihood insensitivity and risk aversion are not related to

Genitalia in human figure drawings: childrearing practices and child sexual abuse.

Science.gov (United States)

Hibbard, R A; Hartman, G

1990-05-01

To replicate and explore the associations of drawing genitalia on a human figure, child-rearing practices, and a history of alleged sexual abuse, we designed a cross-sectional study of 109 alleged child sexual abuse victims, ages 3 through 8 years, and a group of 109 comparison children matched for age, sex, race, and socioeconomic status but with no history of abuse. A standardized format was used to collect drawings, administer the Peabody Picture Vocabulary Test, and gather background data on medical, developmental, and child-rearing issues. Seven alleged sexual abuse victims and one comparison child spontaneously drew genitalia (p = 0.02, one-tailed Fisher Exact Test, estimated relative risk 7.96). No differences in drawing maturity (Draw-A-Man score) were identified, although Peabody Picture Vocabulary Test scores were higher in comparison children (82.1 vs. 91.0, p less than 0.01). Neither drawing genitalia nor history of alleged sexual abuse were significantly associated with histories of medical problems, enuresis, encopresis, urinary tract infection, or child-rearing practices related to sleeping, nudity, bathing, sexual abuse education, or exposure to sexually explicit materials. The similar patterns of child-rearing practices in both samples should make professionals cautious in attributing allegations of abuse to specific child-rearing practices. This study confirms our previous report that the presence of genitalia spontaneously drawn on a child's drawing of a human figure is associated with alleged sexual abuse.

Surface Rendering of External Genitalia of a Fetus at the 32nd Week of Gestation Affected by Partial Androgen Insensitivity Syndrome

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Vincenzo Mazza

2013-01-01

Full Text Available Objectives. To demonstrate the feasibility of the prenatal diagnosis of partial androgen insensitivity syndrome by 3D-4D ultrasound. Methods. To report prenatal diagnosis of partial androgen insensitivity syndrome at 32nd week of gestation by 3D-4D ultrasound in a fetus with a 46XY karyotype, testing negative to the mutation analysis of SRY gene and the 5α-reductase 2 gene (SRD5A2. Results. 3D-4D surface rendering allows the detection of external and internal genital malformations and can address the prenatal diagnosis of PAIS and can exclude associated complications. Conclusions. Prenatal diagnosis of PAIS allows an adequate parental counseling and an early optimal management of the condition, not only for the psychological and social reflections but also for the avoidance of complications and postnatal morbidity due to misdiagnosis or delays in the treatment of the genital ambiguity.

Ambiguously Divided Responsibilities across Government Spheres: How they Impact the Policy Process and Result in Coordination Problems in the Case of Poland

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Hans Dubois

2014-07-01

Full Text Available Empirical studies in decentralized settings associate ambiguities in the division of responsibilities between government spheres with coordination problems. This study explores the mechanisms behind this association, mainly drawing on in-depth interviews with local government officials in Poland. A typology emerges from the data. Ambiguities can refer to the policy content, but also to the rationale behind responsibilities. They may be real or perceived. The agent who perceives the ambiguities can be close to public administration (internal or further removed from it (external. External ambiguities mostly inhibit front-room stages of the policy cycle, while external ambiguities impede back-room stages. Through different paths, they contribute to tensions between government spheres, obstructing cooperation needed to address the ambiguities. Overall, the article contributes to a better understanding of the policy process in decentralized settings, unwraps the dynamic causal framework surrounding the ambiguities, and highlights the role of perceptions, not only by the electorate, but by public officials in particular.

Genitalia morphometry and testicular characteristics of male white ...

African Journals Online (AJOL)

An experiment was designed to evaluate genitalia morphometry of the male white Japanese quails at three different age groups. Fifty-four male Japanese quails were allotted to 3 treatment groups (Pubertal, Mature and Adult) in a completely randomized design. Pubertal (7-10 weeks), mature (15-20 weeks) and the adults ...

Profile of patients with genitourinary anomalies treated in a clinical genetics service in the Brazilian unified health system

Directory of Open Access Journals (Sweden)

Ilanna Fragoso Peixoto Gazzaneo

2016-03-01

Full Text Available Abstract Objective: To describe the profile of patients with genitourinary abnormalities treated at a tertiary hospital genetics service. Methods: Cross-sectional study of 1068 medical records of patients treated between April/2008 and August/2014. A total of 115 cases suggestive of genitourinary anomalies were selected, regardless of age. A standardized clinical protocol was used, as well as karyotype, hormone levels and genitourinary ultrasound for basic evaluation. Laparoscopy, gonadal biopsy and molecular studies were performed in specific cases. Patients with genitourinary malformations were classified as genitourinary anomalies (GUA, whereas the others, as Disorders of Sex Differentiation (DSD. Chi-square, Fisher and Kruskal–Wallis tests were used for statistical analysis and comparison between groups. Results: 80 subjects met the inclusion criteria, 91% with DSD and 9% with isolated/syndromic GUA. The age was younger in the GUA group (p<0.02, but these groups did not differ regarding external and internal genitalia, as well as karyotype. Karyotype 46,XY was verified in 55% and chromosomal aberrations in 17.5% of cases. Ambiguous genitalia occurred in 45%, predominantly in 46,XX patients (p<0.006. Disorders of Gonadal Differentiation accounted for 25% and congenital adrenal hyperplasia, for 17.5% of the sample. Consanguinity occurred in 16%, recurrence in 12%, lack of birth certificate in 20% and interrupted follow-up in 31% of cases. Conclusions: Patients with DSD predominated. Ambiguous genitalia and abnormal sexual differentiation were more frequent among infants and prepubertal individuals. Congenital adrenal hyperplasia was the most prevalent nosology. Younger patients were more common in the GUA group. Abandonment and lower frequency of birth certificate occurred in patients with ambiguous or malformed genitalia. These characteristics corroborate the literature and show the biopsychosocial impact of genitourinary anomalies.

Ambiguity attitudes

NARCIS (Netherlands)

Trautmann, Stefan; van de Kuilen, Gijs; Keren, Gideon; Wu, George

2015-01-01

This chapter reviews the experimental literature on ambiguity attitudes, focusing on three topics. First, it considers various approaches to operationalize ambiguity in experiments. Second, the chapter reviews basic findings in the field regarding the prevalence of ambiguity aversion and ambiguity

Are ambiguity aversion and ambiguity intolerance identical? A neuroeconomics investigation.

Science.gov (United States)

Tanaka, Yusuke; Fujino, Junya; Ideno, Takashi; Okubo, Shigetaka; Takemura, Kazuhisa; Miyata, Jun; Kawada, Ryosaku; Fujimoto, Shinsuke; Kubota, Manabu; Sasamoto, Akihiko; Hirose, Kimito; Takeuchi, Hideaki; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

2014-01-01

In recent years, there has been growing interest in understanding a person's reaction to ambiguous situations, and two similar constructs related to ambiguity, "ambiguity aversion" and "ambiguity intolerance," are defined in different disciplines. In the field of economic decision-making research, "ambiguity aversion" represents a preference for known risks relative to unknown risks. On the other hand, in clinical psychology, "ambiguity intolerance" describes the tendency to perceive ambiguous situations as undesirable. However, it remains unclear whether these two notions derived from different disciplines are identical or not. To clarify this issue, we combined an economic task, psychological questionnaires, and voxel-based morphometry (VBM) of structural brain magnetic resonance imaging (MRI) in a sample of healthy volunteers. The individual ambiguity aversion tendency parameter, as measured by our economic task, was negatively correlated with agreeableness scores on the self-reported version of the Revised NEO Personality Inventory. However, it was not correlated with scores of discomfort with ambiguity, one of the subscales of the Need for Closure Scale. Furthermore, the ambiguity aversion tendency parameter was negatively correlated with gray matter (GM) volume of areas in the lateral prefrontal cortex and parietal cortex, whereas ambiguity intolerance was not correlated with GM volume in any region. Our results suggest that ambiguity aversion, described in decision theory, may not necessarily be identical to ambiguity intolerance, referred to in clinical psychology. Cautious applications of decision theory to clinical neuropsychiatry are recommended.

Relation of tolerance of ambiguity to global and specific paranormal experience.

Science.gov (United States)

Houran, J; Williams, C

1998-12-01

We examined the relationship of tolerance of ambiguity to severe global factors and specific types of anomalous or paranormal experience. 107 undergraduate students completed MacDonald's 1970 AT-20 and the Anomalous Experiences Inventory of Kumar, Pekala, and Gallagher. Scores on the five subscales of the Anomalous Experiences Inventory correlated differently with tolerance of ambiguity. Global paranormal beliefs, abilities, experiences, and drug use were positively associated with tolerance of ambiguity, whereas a fear of paranormal experience showed a negative relation. The specific types of anomalous experiences that correlated with tolerance of ambiguity often involved internal or physiological experience, e.g., precognitive dreams, memories of reincarnation, visual apparitions, and vestibular alterations. We generally found no effects of age of sex. These results are consistent with the idea that some paranormal experiences are misattributions of internal experience to external ('paranormal') sources, a process analogous to mechanisms underpinning delusions and hallucinations.

Bacteriology of the Anterior Genitalia of the Domestic House Cat ...

African Journals Online (AJOL)

The bacteriology of the anterior genitalia of the domestic house cat was determined using vaginal swabs collected from sixty apparently healthy female domestic cats (20 kittens, 20 pregnant and 20 non-pregnant adults). The swabs were streaked on blood agar, Mac Conkey agar and eosin methylene blue agar plates ...

Treatment decisions under ambiguity.

Science.gov (United States)

Berger, Loïc; Bleichrodt, Han; Eeckhoudt, Louis

2013-05-01

Many health risks are ambiguous in the sense that reliable and credible information about these risks is unavailable. In health economics, ambiguity is usually handled through sensitivity analysis, which implicitly assumes that people are neutral towards ambiguity. However, empirical evidence suggests that people are averse to ambiguity and react strongly to it. This paper studies the effects of ambiguity aversion on two classical medical decision problems. If there is ambiguity regarding the diagnosis of a patient, ambiguity aversion increases the decision maker's propensity to opt for treatment. On the other hand, in the case of ambiguity regarding the effects of treatment, ambiguity aversion leads to a reduction in the propensity to choose treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

Image Ambiguity and Fluency

Science.gov (United States)

Jakesch, Martina; Leder, Helmut; Forster, Michael

2013-01-01

Ambiguity is often associated with negative affective responses, and enjoying ambiguity seems restricted to only a few situations, such as experiencing art. Nevertheless, theories of judgment formation, especially the “processing fluency account”, suggest that easy-to-process (non-ambiguous) stimuli are processed faster and are therefore preferred to (ambiguous) stimuli, which are hard to process. In a series of six experiments, we investigated these contrasting approaches by manipulating fluency (presentation duration: 10ms, 50ms, 100ms, 500ms, 1000ms) and testing effects of ambiguity (ambiguous versus non-ambiguous pictures of paintings) on classification performance (Part A; speed and accuracy) and aesthetic appreciation (Part B; liking and interest). As indicated by signal detection analyses, classification accuracy increased with presentation duration (Exp. 1a), but we found no effects of ambiguity on classification speed (Exp. 1b). Fifty percent of the participants were able to successfully classify ambiguous content at a presentation duration of 100 ms, and at 500ms even 75% performed above chance level. Ambiguous artworks were found more interesting (in conditions 50ms to 1000ms) and were preferred over non-ambiguous stimuli at 500ms and 1000ms (Exp. 2a - 2c, 3). Importantly, ambiguous images were nonetheless rated significantly harder to process as non-ambiguous images. These results suggest that ambiguity is an essential ingredient in art appreciation even though or maybe because it is harder to process. PMID:24040172

Measuring higher order ambiguity preferences.

Science.gov (United States)

Baillon, Aurélien; Schlesinger, Harris; van de Kuilen, Gijs

2018-01-01

We report the results from an experiment designed to measure attitudes towards ambiguity beyond ambiguity aversion. In particular, we implement recently-proposed model-free preference conditions of ambiguity prudence and ambiguity temperance. Ambiguity prudence has been shown to play an important role in precautionary behavior and the mere presence of ambiguity averse agents in markets. We observe that the majority of individuals' decisions are consistent with ambiguity aversion, ambiguity prudence and ambiguity temperance. This finding confirms the prediction of many popular (specifications of) ambiguity models and has important implications for models of prevention behavior.

Risk, ambiguity and sovereign rating

OpenAIRE

Di Caro, Paolo

2014-01-01

Decisions of investing in sovereign assets involve both risk and ambiguity. Ambiguity arises from unknown elements characterizing the value of a generic sovereign. In presence of ambiguity, ambiguity-averse investors are prone to pay for obtaining summary information such as ratings which reduces ambiguity. Ambiguity-neutral and ambiguity-averse investors, then, make decisions on the basis of different informative sources. By presenting a simple model of sovereign rating under ambiguity, thre...

Risk, ambiguity, and diversification

OpenAIRE

Sautua, Santiago-Ignacio

2016-01-01

Attitudes toward risk influence the decision to diversify among uncertain options. Yet, because in most situations the options are ambiguous, attitudes toward ambiguity may also play an important role. I conduct a laboratory experiment to investigate the effect of ambiguity on the decision to diversify. I find that diversification is more prevalent and more persistent under ambiguity than under risk. Moreover, excess diversification under ambiguity is driven by participants who stick with a s...

Measuring higher order ambiguity preferences

NARCIS (Netherlands)

A. Baillon (Aurélien); Schlesinger, H. (Harris); G. van de Kuilen (Gijs)

2017-01-01

textabstractWe report the results from an experiment designed to measure attitudes towards ambiguity beyond ambiguity aversion. In particular, we implement recently-proposed model-free preference conditions of ambiguity prudence and ambiguity temperance. Ambiguity prudence has been shown to play an

Ambiguous chair

DEFF Research Database (Denmark)

Manelius, Anne-Mette

2011-01-01

Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol.......Bidrag til gør-det-selv bog, hvor det beskrives i udførlige tegninger, hvordan man bygger sin egen 'Ambiguous Chair', en tekstilforskallet stol....

Clinical use of anti-Müllerian hormone (AMH) determinations in patients with disorders of sex development

DEFF Research Database (Denmark)

Hagen, Casper P; Aksglaede, Lise; Sørensen, Kaspar

2011-01-01

Determination of postnatal AMH levels in circulation has been used for decades when evaluating a child with ambiguous genitalia. We describe the age- and gender-specific changes of postnatal AMH serum levels to enable an appropriate clinical use of AMH assessment in pediatric endocrinology...... the sexes until puberty. Ambiguous genitalia due to impaired androgen secretion or action may be a result of various conditions with low, normal or high AMH. Furthermore, low AMH is a marker of premature ovarian failure in Turner Syndrome girls. Measurement of AMH is an important tool in assessing gonadal...

The Ethics of Ambiguity

Science.gov (United States)

2016-01-01

Understanding and embracing uncertainty are critical for effective teacher–learner relationships as well as for shared decision-making in the physician–patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity. PMID:28725771

Exploring ambiguous realms

DEFF Research Database (Denmark)

Clemensen, Nana

2016-01-01

In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities in their intera...... in their interactions, testing social roles and conventions. This article explores the vigilance and creative agency displayed by Hang'ombe children, in an environment spurring their acquisition of distinct social and discursive skills.......In Hang'ombe Village in rural Zambia, the relative lack of physical boundaries between the activities of family members allow children to observe the actions and discussions of adults on close hand, exposing them to the ambiguities of daily life. Children explore these ambiguities...

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXV. Genus Elpeytonius Reinert, Harbach and Kitching

Science.gov (United States)

A comparative, morphological analysis of the female genitalia of species included in genus Elpeytonius Reinert, Harbach and Kitching was conducted. The genitalia of the two species included in the genus, El. apicoannulatus (Edwards) and El. simulans (Newstead and Carter), are illustrated. Treatmen...

Red is not a proxy signal for female genitalia in humans.

Directory of Open Access Journals (Sweden)

Sarah E Johns

Full Text Available Red is a colour that induces physiological and psychological effects in humans, affecting competitive and sporting success, signalling and enhancing male social dominance. The colour is also associated with increased sexual attractiveness, such that women associated with red objects or contexts are regarded as more desirable. It has been proposed that human males have a biological predisposition towards the colour red such that it is 'sexually salient'. This hypothesis argues that women use the colour red to announce impending ovulation and sexual proceptivity, with this functioning as a proxy signal for genital colour, and that men show increased attraction in consequence. In the first test of this hypothesis, we show that contrary to the hypothesis, heterosexual men did not prefer redder female genitalia and, by extension, that red is not a proxy signal for genital colour. We found a relative preference for pinker genital images with redder genitalia rated significantly less sexually attractive. This effect was independent of raters' prior sexual experience and variation in female genital morphology. Our results refute the hypothesis that men's attraction to red is linked to an implied relationship to genital colour and women's signalling of fertility and sexual proceptivity.

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXII. Genus Jarnellius Reinert, Harbach and Kitching

Science.gov (United States)

A comparative, morphological analysis of the female genitalia of species included in genus Jarnellius Reinert, Harbach and Kitching was conducted. The female genitalia of the genus are characterized and a comparison with other taxa is provided. The type species of the genus, Ja. varipalpus (Coquil...

The Ethics of Ambiguity

Directory of Open Access Journals (Sweden)

Ronald E. Domen MD

2016-06-01

Full Text Available Understanding and embracing uncertainty are critical for effective teacher–learner relationships as well as for shared decision-making in the physician–patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity.

ROLE CONFLICT AND ROLE AMBIGUITY ON LOCAL GOVERNMENT INTERNAL AUDITORS: THE DETERMINANT AND IMPACTS

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Agil Novriansa

2016-01-01

Full Text Available The bureaucratic reform at the local government level in Indonesia that was instituted in 2012 has turned local government internal auditors into an important part of government governance systems. The role of local government internal auditors has been expanded to include not only the area of audit oversight, but also the areas of anti-corruption-related and consulting activities. These fundamental changes may potentially induce role conflict and role ambiguity among internal auditors. The objective of this study is to examine empirically the determinants and consequences of role conflict and role ambiguity among local government internal auditors. More specifically, this study attempts to examine the extent to which formalization determines role conflict and role ambiguity; it further tests the impact of role conflict and role ambiguity on commitment to independence and job performance. Questionnaires were distributed to 248 local government internal auditors from 12 Regional Inspectorates in the provinces of Yogyakarta, South Sumatra, and East Java. A total of 176 responses were received, and 124 useable responses from the 176 responses were analysed to test the hypotheses. Using Structural Equation Modelling-Partial Least Square the results show that: formalization is negatively related to role conflict and role ambiguity; role ambiguity has a negative impact on commitment to independence; role conflict has a positive impact on job performance; and role ambiguity has a negative impact on job performance. These findings serve as important external validity evidence on the phenomena associated with role conflict and role ambiguity that occur in the public sector, especially among internal auditors at local government institutions.

Theory-Based Evaluation Meets Ambiguity

DEFF Research Database (Denmark)

Dahler-Larsen, Peter

2017-01-01

As theory-based evaluation (TBE) engages in situations where multiple stakeholders help develop complex program theory about dynamic phenomena in politically contested settings, it becomes difficult to develop and use program theory without ambiguity. The purpose of this article is to explore...... ambiguity as a fruitful perspective that helps TBE face current challenges. Literatures in organization theory and political theory are consulted in order to cultivate the concept of ambiguity. Janus variables (which work in two ways) and other ambiguous aspects of program theories are classified...... and exemplified. Stances towards ambiguity are considered, as are concrete steps that TBE evaluators can take to identify and deal with ambiguity in TBE....

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXIII. Genus Lewnielsenius Reinert, Harbach and Kitching

Science.gov (United States)

A morphological analysis of the female genitalia of the species included in genus Lewnielsenius Reinert, Harbach and Kitching was conducted. The genitalia of the type species of the genus, Ln. muelleri (Dyar), are illustrated. Treatment of the genital morphology of the genus includes a detailed de...

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXX. Genus Gilesius Reinert, Harbach and Kitching.

Science.gov (United States)

A morphological analysis of the female genitalia of species included in genus Gilesius Reinert, Harbach and Kitching was conducted. The genitalia of the type species of the genus, Gi. pulchriventer (Giles), are illustrated for the first time. Treatment of the genital morphology of the genus includ...

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXI. Genus Sallumia Reinert, Harbach and Kitching

Science.gov (United States)

A morphological analysis of the female genitalia of species included in genus Sallumia Reinert, Harbach and Kitching was conducted. The genitalia of the type species of the genus, Sl. hortator (Dyar and Knab), are illustrated. Treatment of the genital morphology of the genus includes a description...

Ambiguity aversion in schizophrenia: An fMRI study of decision-making under risk and ambiguity.

Science.gov (United States)

Fujino, Junya; Hirose, Kimito; Tei, Shisei; Kawada, Ryosaku; Tsurumi, Kosuke; Matsukawa, Noriko; Miyata, Jun; Sugihara, Genichi; Yoshihara, Yujiro; Ideno, Takashi; Aso, Toshihiko; Takemura, Kazuhisa; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

2016-12-01

When making decisions in everyday life, we often have to choose between uncertain outcomes. Economic studies have demonstrated that healthy people tend to prefer options with known probabilities (risk) than those with unknown probabilities (ambiguity), which is referred to as "ambiguity aversion." However, it remains unclear how patients with schizophrenia behave under ambiguity, despite growing evidence of their altered decision-making under uncertainty. In this study, combining economic tools and functional magnetic resonance imaging (fMRI), we assessed the attitudes toward risk/ambiguity and investigated the neural correlates during decision-making under risk/ambiguity in schizophrenia. Although no significant difference in attitudes under risk was observed, patients with schizophrenia chose ambiguity significantly more often than the healthy controls. Attitudes under risk and ambiguity did not correlate across patients with schizophrenia. Furthermore, unlike in the healthy controls, activation of the left lateral orbitofrontal cortex was not increased during decision-making under ambiguity compared to under risk in schizophrenia. These results suggest that ambiguity aversion, a well-established subjective bias, is attenuated in patients with schizophrenia, highlighting the need to distinguish between risk and ambiguity when assessing decision-making under these situations. Our findings, comprising important clinical implications, contribute to improved understanding of the mechanisms underlying altered decision-making in patients with schizophrenia. Copyright © 2016 Elsevier B.V. All rights reserved.

X-ray microtomography (microCT of male genitalia of Nothybus kuznetsovorum (Nothybidae and Cothornobata sp. (Micropezidae

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Tatiana V. Galinskaya

2018-03-01

Full Text Available The results of manual dissection of the musculature of the male genitalia in Nothybus kuznetsovorum are fully confirmed by the modern methods of Micro-CT. A comparative analysis of Neria commutata and Cothornobata sp. shows that an increase in the flexion in the genitalia of males and the displacement of syntergosternite VII to the ventral side in Cothornobata sp. caused the disappearance of the muscles ITM6–7r and ITM7–8r. In addition, this increase in flexion apparently caused the fusion of the M18 muscles into one bundle. The muscle ISM5-6c goes on to moving the second segment of the forcipate appendages of sternite V.

Clinical profile of congenital adrenal hyperplasia and short-term response to treatment

International Nuclear Information System (INIS)

Lal, S.; Lal, S.; Jamro, B.U.; Jamro, S.

2015-01-01

To determine the clinical presentation of congenital adrenal hyperplasia and short- term response to treatment. Background: Congenital adrenal hyperplasia (CAH) is a genetic disorder which usually presents with life threatening emergencies. Awareness of physicians regarding these presentations is an essential for early diagnosis and lifesaving treatment. In view of the prevalence of the condition as reported from tertiary care centers within the country and other parts of the globe, we had carried out a study in the paediatric department of Shaheed Mohtrama Benazir Bhutto Medical University Larkana. Material and Methods: The study was conducted over a period of one year from July 2012 to June 2013. All infants presenting with vomiting, dehydration, shock, failure to thrive and ambiguous genitalia were examined and investigated thoroughly. The diagnosis was based upon a raised level of serum 17 OHP in a child with suggestive clinical features. Results: A total of 40 children were diagnosed to have CAH during the study period. The major presenting features were vomiting in 13 (32.5%), ambiguous genitalia 17 (42.5%), vomiting and ambiguous genitalia 10 (25%), shock 5(12.5%) and failure to thrive in 13 (32.5%) of cases. All the patients were followed up after initiation of treatment and good response was observed to short-term treatment. Conclusion: This study highlights the importance of common clinical features like vomiting, unreasonable dehydration, shock and ambiguous genitalia being the presenting features of CAH and the effectiveness of replacement therapy in amending life threatening emergencies due to this condition. (author)

Delineation of an Isodicentric Y Chromosome in a Mosaic 45,X/46,X,idic(Y(qter-p11.3:: p11.3-qter Fetus by SRY Sequencing, G-banding, FISH, SKY and Study of Distribution in Different Tissues

Directory of Open Access Journals (Sweden)

Hsuan-Hsuan Wu

2007-05-01

Full Text Available Many factors such as genetic, developmental and hormonal are involved in mammalian sex determination. The relative importance and the mutual interactions among those factors are obscure. Study of cytogenetic mosaicism involving sex chromosomes may help to further unravel the mysterious process. We report a fetus with a mosaic karyotype, 45,X/46,X,idic(Y(qter-p11.3::p11.3-qter, with unambiguous male external genitalia and a defect in the interventricular septum of the heart. Genotype of this fetus was extensively studied by technologies including sequencing of SRY (sex-determining region on the Y chromosome gene, G-banding, FISH (fluorescence in situ hybridization and SKY (spectral karyotyping. A markedly higher percentage of Y-containing cells was observed in the gonads (55% than in the amniotic fluid (17% and placental villi (11%, which was considered to be the major reason why the fetus did not have ambiguous genitalia.

Ambiguity aversion in rhesus macaques

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Benjamin eHayden

2010-09-01

Full Text Available People generally prefer risky options, which have fully specified outcome probabilities, to ambiguous options, which have unspecified probabilities. This preference, formalized in economics, is strong enough that people will reliably prefer a risky option to an ambiguous option with a greater expected value. Explanations for ambiguity aversion often invoke uniquely human faculties like language, self-justification, or a desire to avoid public embarrassment. Challenging these ideas, here we demonstrate that a preference for unambiguous options is shared with rhesus macaques. We trained four monkeys to choose between pairs of options that both offered explicitly cued probabilities of large and small juice outcomes. We then introduced occasional trials where one of the options was obscured and examined their resulting preferences; we ran humans in a parallel experiment on a nearly identical task. We found that monkeys reliably preferred risky options to ambiguous ones, even when this bias was costly, closely matching the behavior of humans in the analogous task. Notably, ambiguity aversion varied parametrically with the extent of ambiguity. As expected, ambiguity aversion gradually declined as monkeys learned the underlying probability distribution of rewards. These data indicate that ambiguity aversion reflects fundamental cognitive biases shared with other animals rather than uniquely human factors guiding decisions.

Resurrecting embryos of the tuatara, Sphenodon punctatus, to resolve vertebrate phallus evolution.

Science.gov (United States)

Sanger, Thomas J; Gredler, Marissa L; Cohn, Martin J

2015-10-01

The breadth of anatomical and functional diversity among amniote external genitalia has led to uncertainty about the evolutionary origins of the phallus. In several lineages, including the tuatara, Sphenodon punctatus, adults lack an intromittent phallus, raising the possibility that the amniote ancestor lacked external genitalia and reproduced using cloacal apposition. Accordingly, a phallus may have evolved multiple times in amniotes. However, similarities in development across amniote external genitalia suggest that the phallus may have a single evolutionary origin. To resolve the evolutionary history of amniote genitalia, we performed three-dimensional reconstruction of Victorian era tuatara embryos to look for embryological evidence of external genital initiation. Despite the absence of an intromittent phallus in adult tuataras, our observations show that tuatara embryos develop genital anlagen. This illustrates that there is a conserved developmental stage of external genital development among all amniotes and suggests a single evolutionary origin of amniote external genitalia. © 2015 The Author(s).

Five-year-olds do not show ambiguity aversion in a risk and ambiguity task with physical objects.

Science.gov (United States)

Li, Rosa; Roberts, Rachel C; Huettel, Scott A; Brannon, Elizabeth M

2017-07-01

Ambiguity aversion arises when a decision maker prefers risky gambles with known probabilities over equivalent ambiguous gambles with unknown probabilities. This phenomenon has been consistently observed in adults across a large body of empirical work. Evaluating ambiguity aversion in young children, however, has posed methodological challenges because probabilistic representations appropriate for adults might not be understood by young children. Here, we established a novel method for representing risk and ambiguity with physical objects that overcomes previous methodological limitations and allows us to measure ambiguity aversion in young children. We found that individual 5-year-olds exhibited consistent choice preferences and, as a group, exhibited no ambiguity aversion in a task that evokes ambiguity aversion in adults. Across individuals, 5-year-olds exhibited greater variance in ambiguity preferences compared with adults tested under similar conditions. This suggests that ambiguity aversion is absent during early childhood and emerges over the course of development. Copyright © 2017 Elsevier Inc. All rights reserved.

Determinants of translation ambiguity

Science.gov (United States)

Degani, Tamar; Prior, Anat; Eddington, Chelsea M.; Arêas da Luz Fontes, Ana B.; Tokowicz, Natasha

2016-01-01

Ambiguity in translation is highly prevalent, and has consequences for second-language learning and for bilingual lexical processing. To better understand this phenomenon, the current study compared the determinants of translation ambiguity across four sets of translation norms from English to Spanish, Dutch, German and Hebrew. The number of translations an English word received was correlated across these different languages, and was also correlated with the number of senses the word has in English, demonstrating that translation ambiguity is partially determined by within-language semantic ambiguity. For semantically-ambiguous English words, the probability of the different translations in Spanish and Hebrew was predicted by the meaning-dominance structure in English, beyond the influence of other lexical and semantic factors, for bilinguals translating from their L1, and translating from their L2. These findings are consistent with models postulating direct access to meaning from L2 words for moderately-proficient bilinguals. PMID:27882188

Trastornos de la diferenciación sexual: presentación de un caso de genitales ambiguos y revisión del tema Disorders of sexual differentiation: a case presentation of ambiguous genitalia and literature review on this topic

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Yoerquis Mejías Sánchez

2007-09-01

Full Text Available Los trastornos de la diferenciación sexual constituyen un grupo complejo de entidades y síndromes. El término estados intersexuales hace referencia a aquellos recién nacidos que presentan genitales ambiguos, esto es, sin evidencia clara sobre sexo asignable. Su frecuencia en nuestro medio es relativamente escasa. Se presenta el caso de un recién nacido en el que, en el examen físico, presenta micropenisomía y escroto bífido. La fusión labioescrotal está alterada con rodetes separados que semejan labios mayores y una estructura que remeda un introito vaginal. En el estudio ultrasonográfico se descartó la presencia de útero y ovarios y se constató la presencia de testículos en canal inguinal. La cromatina sexual de células en interfase de la mucosa oral reveló la presencia de 0 % de cuerpo Barr y el estudio cromosómico mostró un cariotipo masculino normal (46, XY, por lo que se interpreta el caso como un pseudohermafroditismo masculino. Se realiza una revisión de los trastornos de la diferenciación sexual.Sexual differentiation disorders constitute a group of complex syndromes and entities. The term intersexual states makes reference to those newborns that present with ambiguos genitalia, that is, without any clear evidence of defined sex. Intersexuality may be classified as masculine and femenine pseudohermaphroditism and true hermaphroditism, which is caused by incomplete sexual differentiation in the male or virilization in the female. This disorder is relatively rare in our context, though knowledge increases more and more about it thanks to the development of molecular biology and the discovered involvement of genes in the normal sexual differentiation process. This article presented the case of a newborn whose dysmorphological exam at birth indicated positive findings in external genitalia such as micropenis and bifid scrotum. Labioscrotal fusion was upset with separated folds resembling labia majoris and a structure

Ambiguity aversion is not universal

NARCIS (Netherlands)

Kocher, M.G.; Lahno, Amrei; Trautmann, Stefan

Assuming universal ambiguity aversion, an extensive theoretical literature studies how ambiguity can account for market anomalies from the perspective of expected utility-based theories. We provide a systematic experimental assessment of ambiguity attitudes in different likelihood ranges, and in the

Effective ambiguity checking in biosequence analysis

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Giegerich Robert

2005-06-01

Full Text Available Abstract Background Ambiguity is a problem in biosequence analysis that arises in various analysis tasks solved via dynamic programming, and in particular, in the modeling of families of RNA secondary structures with stochastic context free grammars. Several types of analysis are invalidated by the presence of ambiguity. As this problem inherits undecidability (as we show here from the namely problem for context free languages, there is no complete algorithmic solution to the problem of ambiguity checking. Results We explain frequently observed sources of ambiguity, and show how to avoid them. We suggest four testing procedures that may help to detect ambiguity when present, including a just-in-time test that permits to work safely with a potentially ambiguous grammar. We introduce, for the special case of stochastic context free grammars and RNA structure modeling, an automated partial procedure for proving non-ambiguity. It is used to demonstrate non-ambiguity for several relevant grammars. Conclusion Our mechanical proof procedure and our testing methods provide a powerful arsenal of methods to ensure non-ambiguity.

Vignettes of Ambiguity

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Gotz, Ignacio L.

2010-01-01

This article is an exploration of ambiguity as it appears in various guises in philosophical, social, political, and educational situations. Among these situations is the experience of exile. The exploration is conducted by means of literary anecdotes and real-life instances, hence the use of vignettes. The suggestion is made that ambiguity can be…

Properties of Ambiguity Functions

OpenAIRE

Mulcahy-Stanislawczyk, John

2014-01-01

The use of ambiguity functions in radar signal design and analysis is very common. Understanding the various properties and meanings of ambiguity functions allow a signal designer to understand the time delay and doppler shift properties of a given signal. Through the years, several different versions of the ambiguity function have been used. Each of these functions essentially have the same physical meaning; however, the use of different functions makes it difficult to be sure that certai...

Lexical ambiguity resolution

Energy Technology Data Exchange (ETDEWEB)

Small, S.; Cottrell, G.; Tanenhaus, M.

1987-01-01

This book collects much of the best research currently available on the problem of lexical ambiguity resolution in the processing of human language. When taken out of context, sentences are usually ambiguous. When actually uttered in a dialogue or written in text, these same sentences often have unique interpretations. The inherent ambiguity of isolated sentences, becomes obvious in the attempt to write a computer program to understand them. Different views have emerged on the nature of context and the mechanisms by which it directs unambiguous understanding of words and sentences. These perspectives are represented and discussed. Eighteen original papers from a valuable source book for cognitive scientists in AI, psycholinguistics, neuropsychology, or theoretical linguistics.

Female genitalia concealment promotes intimate male courtship in a water strider.

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Chang S Han

2009-06-01

Full Text Available Violent coercive mating initiation is typical for animals with sexual conflict over mating. In these species, the coevolutionary arms-race between female defenses against coercive mating and male counter-adaptations for increased mating success leads to coevolutionary chases of male and female traits that influence the mating. It has been controversial whether one of the sexes can evolve traits that allow them to "win" this arms race. Here, we use morphological analysis (traditional and scanning electron micrographs, laboratory experiments and comparative methods to show how females of a species characterized by typical coercive mating initiation appear to "win" a particular stage of the sexual conflict by evolving morphology to hide their genitalia from direct, forceful access by males. In an apparent response to the female morphological adaptation, males of this species added to their typically violent coercive mounting of the female new post-mounting, pre-copulatory courtship signals produced by tapping the water's surface with the mid-legs. These courtship signals are intimate in the sense that they are aimed at the female, on whom the male is already mounted. Females respond to the signals by exposing their hidden genitalia for copulatory intromission. Our results indicate that the apparent victory of coevolutionary arms race by one sex in terms of morphology may trigger evolution of a behavioral phenotype in the opposite sex.

Evolution of male and female genitalia following release from sexual selection.

Science.gov (United States)

Cayetano, Luis; Maklakov, Alexei A; Brooks, Robert C; Bonduriansky, Russell

2011-08-01

Despite the key functions of the genitalia in sexual interactions and fertilization, the role of sexual selection and conflict in shaping genital traits remains poorly understood. Seed beetle (Callosobruchus maculatus) males possess spines on the intromittent organ, and females possess a thickened reproductive tract wall that also bears spines. We investigated the role of sexual selection and conflict by imposing monogamous mating on eight replicate populations of this naturally polygamous insect, while maintaining eight other populations under polygamy. To establish whether responses to mating system manipulation were robust to ecological context, we simultaneously manipulated life-history selection (early/late reproduction). Over 18-21 generations, male genital spines evolved relatively reduced length in large males (i.e., shallower static allometry) in monogamous populations. Two nonintromittent male genital appendages also evolved in response to the interaction of mating system and ecology. In contrast, no detectable evolution occurred in female genitalia, consistent with the expectation of a delayed response in defensive traits. Our results support a sexually antagonistic role for the male genital spines, and demonstrate the evolution of static allometry in response to variation in sexual selection opportunity. We argue that further advances in the study of genital coevolution will require a much more detailed understanding of the functions of male and female genital traits. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Neural Mechanisms Underlying Risk and Ambiguity Attitudes.

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Blankenstein, Neeltje E; Peper, Jiska S; Crone, Eveline A; van Duijvenvoorde, Anna C K

2017-11-01

Individual differences in attitudes to risk (a taste for risk, known probabilities) and ambiguity (a tolerance for uncertainty, unknown probabilities) differentially influence risky decision-making. However, it is not well understood whether risk and ambiguity are coded differently within individuals. Here, we tested whether individual differences in risk and ambiguity attitudes were reflected in distinct neural correlates during choice and outcome processing of risky and ambiguous gambles. To these ends, we developed a neuroimaging task in which participants ( n = 50) chose between a sure gain and a gamble, which was either risky or ambiguous, and presented decision outcomes (gains, no gains). From a separate task in which the amount, probability, and ambiguity level were varied, we estimated individuals' risk and ambiguity attitudes. Although there was pronounced neural overlap between risky and ambiguous gambling in a network typically related to decision-making under uncertainty, relatively more risk-seeking attitudes were associated with increased activation in valuation regions of the brain (medial and lateral OFC), whereas relatively more ambiguity-seeking attitudes were related to temporal cortex activation. In addition, although striatum activation was observed during reward processing irrespective of a prior risky or ambiguous gamble, reward processing after an ambiguous gamble resulted in enhanced dorsomedial PFC activation, possibly functioning as a general signal of uncertainty coding. These findings suggest that different neural mechanisms reflect individual differences in risk and ambiguity attitudes and that risk and ambiguity may impact overt risk-taking behavior in different ways.

Sirenomelia: a review of embryogenic theories and discussion of the differences from caudal regression syndrome.

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Isik Kaygusuz, Ecmel; Kurek Eken, Meryem; Sivrikoz, Oya Nermin; Cetiner, Handan

2016-03-01

To discuss the pathological features of sirenomelia in the light of our 10 cases and review the current theories. We identified 10 patients with sirenomelia from our hospital database. All clinical details and the autopsy features of 10 cases were noted. Of the 10 children with sirenomelia seven had bilateral renal agenesis, three had bladder agenesis and one had a renal hypoplasia. Single umbilical artery was found in 60% of children with sirenomelia. External genitalia was ambiguous in seven of 10 patients. Even though the etiology of caudal regression syndrome (CRS) and sirenomelia remains unknown we tend to believe that sirenomelia and CRS might be different entities.

Sampling experience reverses preferences for ambiguity

NARCIS (Netherlands)

Ert, E.; Trautmann, S.T.

People often need to choose between alternatives with known probabilities (risk) and alternatives with unknown probabilities (ambiguity). Such decisions are characterized by attitudes towards ambiguity, which are distinct from risk attitudes. Most studies of ambiguity attitudes have focused on the

Brucella melitensis: a rarely suspected cause of infections of genitalia and the lower urinary tract

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K. Stamatiou

Full Text Available We examined the clinical presentation and outcome of Brucellar infections of genitalia and the lower urinary tract through a review of the medical records of 10 cases of male patients with brucellar infections of the genitalia and lower urinary tract. The mean age of the patients with brucellosis was 49.2, (median 52, range 15-77 years. Eleven out of 17 patients were rural residents, 15 reported that they might have consumed unpasteurized dairy products and four reported occupational exposure. Symptoms onset was acute in almost all cases. Scrotal pain, epidedimal swelling and fever were the most common symptoms. The Wright test was positive in 13 patients, while Brucella sp. was isolated from blood cultures in six cases. Only two patients were found with abnormal liver ultrasonography. All patients underwent treatment with doxycycline and aminoglycoside for seven days and doxycycline alone for two months. Most of them responded to antibiotic therapy with rapid regression of symptoms. One patient failed to respond to therapy and presented necrotizing orchitis, as well as abscesses, which required orchectomy. Brucellar infections of the genitalia and lower urinary tract have no specific clinical presentation; the usual laboratory examination is not sufficient to diagnose this kind of infection, therefore it could easily be misdiagnosed. An analytical medical history (including overall dietary habits and recent consumption of non-pasteurized dairy products could indicate Brucelosis as would the persistence of symptoms despite a one-week antibiotic treatment. In general, patients afflicted by brucellar epididymoorchitis respond to Brucellosis antibiotic therapy, except for some rare cases that present necrotizing orchitis and require surgical treatment.

Ambiguity effects of rhyme and meter.

Science.gov (United States)

Wallot, Sebastian; Menninghaus, Winfried

2018-04-23

Previous research has shown that rhyme and meter-although enhancing prosodic processing ease and memorability-also tend to make semantic processing more demanding. Using a set of rhymed and metered proverbs, as well as nonrhymed and nonmetered versions of these proverbs, the present study reveals this hitherto unspecified difficulty of comprehension to be specifically driven by perceived ambiguity. Roman Jakobson was the 1st to propose this hypothesis, in 1960. He suggested that "ambiguity is an intrinsic, inalienable feature" of "parallelistic" diction of which the combination of rhyme and meter is a pronounced example. Our results show that ambiguity indeed explains a substantial portion of the rhyme- and meter-driven difficulty of comprehension. Longer word-reading times differentially reflected ratings for ambiguity and comprehension difficulty. However, the ambiguity effect is not "inalienable." Rather, many rhymed and metered sentences turned out to be low in ambiguity. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Measuring the environmental benefits of hydrogen transportation fuel cycles under uncertainty about external costs

International Nuclear Information System (INIS)

Chernyavs'ka, Liliya; Gulli, Francesco

2010-01-01

In this paper, we attempt to measure the environmental benefits of hydrogen deployment in the transportation sector. We compare the hydrogen pathways to the conventional transportation fuel cycles in terms of external costs, estimated using the results of the most accurate methodologies available in this field. The central values of performed analysis bring us ambiguous results. The external cost of the best conventional solution ('oil to diesel hybrid internal-combustion engine') in some cases is just higher and in others just lower than that of the best fossil fuel to hydrogen solution ('natural gas to hydrogen fuel cell'). Nevertheless, by accounting for the uncertainty about external costs, we are able to remove this ambiguity highlighting that the hydrogen pathway provides significant environmental benefits ,especially in densely populated areas, assuming 100% city driving.

Phonological ambiguity modulates resolution of semantic ambiguity during reading: An fMRI study of Hebrew.

Science.gov (United States)

Bitan, Tali; Kaftory, Asaf; Meiri-Leib, Adi; Eviatar, Zohar; Peleg, Orna

2017-10-01

The current fMRI study examined the role of phonology in the extraction of meaning from print in each hemisphere by comparing homophonic and heterophonic homographs (ambiguous words in which both meanings have the same or different sounds respectively, e.g., bank or tear). The analysis distinguished between the first phase, in which participants read ambiguous words without context, and the second phase in which the context resolves the ambiguity. Native Hebrew readers were scanned during semantic relatedness judgments on pairs of words in which the first word was either a homophone or a heterophone and the second word was related to its dominant or subordinate meaning. In Phase 1 there was greater activation for heterophones in left inferior frontal gyrus (IFG), pars opercularis, and more activation for homophones in bilateral IFG pars orbitalis, suggesting that resolution of the conflict at the phonological level has abolished the semantic ambiguity for heterophones. Reduced activation for all ambiguous words in temporo-parietal regions suggests that although ambiguity enhances controlled lexical selection processes in frontal regions it reduces reliance on bottom-up mapping processes. After presentation of the context, a larger difference between the dominant and subordinate meaning was found for heterophones in all reading-related regions, suggesting a greater engagement for heterophones with the dominant meaning. Altogether these results are consistent with the prominent role of phonological processing in visual word recognition. Finally, despite differences in hemispheric asymmetry between homophones and heterophones, ambiguity resolution, even toward the subordinate meaning, is largely left lateralized. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Patients' Priorities Regarding Female-to-Male Gender Affirmation Surgery of the Genitalia-A Pilot Study of 47 Patients in Sweden.

Science.gov (United States)

Jacobsson, Josephine; Andréasson, My; Kölby, Lars; Elander, Anna; Selvaggi, Gennaro

2017-06-01

No surgical technique is reported to be the best option for gender-affirmation surgery (GAS) of the genitalia in transmen. Although patients' preferences are central when choosing a surgical technique, no studies have evaluated this factor. To investigate transmen's priorities and preferences regarding GAS of the genitalia. From November 2015 to March 2016, 54 transmen with the diagnosis of gender dysphoria who were referred to Sahlgrenska University Hospital for discussion of therapeutic steps (surgery and hormonal treatments) were asked to complete a questionnaire on different attributes achievable with GAS, such as sexual and urinary function and appearance. Forty-seven patients (87%) completed the questionnaire. Age ranged from 18 to 52 years (mean = 26 years, SD = 7.4 years). At the time of interview, no patient had undergone GAS of the genitalia. Answers to completed questionnaires. Seventy-six percent of patients identified themselves as male, and 24% wrote other terms such as "mostly male," "inter-gender" and "non-binary." Gender identity had a significant impact on patients' preferences for two questions: the importance of vaginal removal and the importance of having a penis that would be passable in places such as male dressing rooms. These items were more important to patients identifying themselves as male. The most important attributes requested were preserved orgasm ability and tactile sensation. The least important attribute was removal of the vagina, followed by having a penis of human material, minimal scarring, and size. The ability to urinate while standing was considered a high priority by some and a low priority by others. All answers ranged from "unimportant" to "imperative." This series of patients demonstrates a considerable heterogeneity among transmen in their gender identity and preferences regarding GAS of the genitalia, which supports the need for several techniques. Patients must be accurately informed on the different techniques and

A Neural Signature Encoding Decisions under Perceptual Ambiguity.

Science.gov (United States)

Sun, Sai; Yu, Rongjun; Wang, Shuo

2017-01-01

People often make perceptual decisions with ambiguous information, but it remains unclear whether the brain has a common neural substrate that encodes various forms of perceptual ambiguity. Here, we used three types of perceptually ambiguous stimuli as well as task instructions to examine the neural basis for both stimulus-driven and task-driven perceptual ambiguity. We identified a neural signature, the late positive potential (LPP), that encoded a general form of stimulus-driven perceptual ambiguity. In addition to stimulus-driven ambiguity, the LPP was also modulated by ambiguity in task instructions. To further specify the functional role of the LPP and elucidate the relationship between stimulus ambiguity, behavioral response, and the LPP, we employed regression models and found that the LPP was specifically associated with response latency and confidence rating, suggesting that the LPP encoded decisions under perceptual ambiguity. Finally, direct behavioral ratings of stimulus and task ambiguity confirmed our neurophysiological findings, which could not be attributed to differences in eye movements either. Together, our findings argue for a common neural signature that encodes decisions under perceptual ambiguity but is subject to the modulation of task ambiguity. Our results represent an essential first step toward a complete neural understanding of human perceptual decision making.

Analyzing Ambiguity of Context-Free Grammars

DEFF Research Database (Denmark)

Brabrand, Claus; Giegerich, Robert; Møller, Anders

2010-01-01

It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. We...... observe that there is a simple linguistic characterization of the grammar ambiguity problem, and we show how to exploit this by presenting an ambiguity analysis framework based on conservative language approximations. As a concrete example, we propose a technique based on local regular approximations...

Symbol in View of Ambiguity

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Mohamad reza Yousefi

2013-11-01

Full Text Available Abstract Symbol from the perspective of rhetorical word, is phrase or sentence that apparent meaning, also inspires to reader a wide range of semantic.Since exploring the complex social and political ideas in the most mysticalway and indirectreflectionsocial and political thoughts symbolically is easier, so the symbol and symbolism especially in Persian literatureespeciallyin the realm of Persian poetry, has a special appearance.In addition to the factors mentioned in the contemporary literature, according familiar in literature and the emergence of particular schools interest toambiguoussymbolization has spreadfurther, especially the symbol has all the features of art ambiguity in the poem and it isone the major factors causing uncertainty.Thus, the precise definitions and symbols of contemporary poetry could be dominant in the unwinding ambiguous symbol detection of cryptic allusions and metaphors that matches the cursor symbol to help readers.  In the literature, especially language poetry, the inability of language toreflecting obscure mystical ideas, avoid to directexpression of political and social concerns of the reader in the course of participate to creation ambiguous literary works is the main motivation towards symbol and symbolization.According widespread use of symbol and its different of species can be viewed from different perspectives.The creation of ambiguity is the main purposes of using symbols (especially in poetry, so many poets have tried to achieve this goal have to formation of similar symbols and the explanation and resolution of this issue can open new window for understanding the poetry in front of an audience.  In this paper examines the ambiguity of symbols in terms of its precise boundaries are reviewed. Ambiguity is one of the important processes and also is the key Iranian poetry its means is today poetry. In such poetry ambiguity is a need to explore the new world from a different perspective, or explore this

Generative Learning: Adults Learning within Ambiguity

Science.gov (United States)

Nicolaides, Aliki

2015-01-01

This study explored the extent to which ambiguity can serve as a catalyst for adult learning. The purpose of this study is to understand learning that is generated when encountering ambiguity agitated by the complexity of liquid modernity. "Ambiguity," in this study, describes an encounter with an appearance of reality that is at first…

Positive fEMG Patterns with Ambiguity in Paintings.

Science.gov (United States)

Jakesch, Martina; Goller, Juergen; Leder, Helmut

2017-01-01

Whereas ambiguity in everyday life is often negatively evaluated, it is considered key in art appreciation. In a facial EMG study, we tested whether the positive role of visual ambiguity in paintings is reflected in a continuous affective evaluation on a subtle level. We presented ambiguous (disfluent) and non-ambiguous (fluent) versions of Magritte paintings and found that M. Zygomaticus major activation was higher and M. corrugator supercilii activation was lower for ambiguous than for non-ambiguous versions. Our findings reflect a positive continuous affective evaluation to visual ambiguity in paintings over the 5 s presentation time. We claim that this finding is indirect evidence for the hypothesis that visual stimuli classified as art, evoke a safe state for indulging into experiencing ambiguity, challenging the notion that processing fluency is generally related to positive affect.

Instantaneous and controllable integer ambiguity resolution: review and an alternative approach

Science.gov (United States)

Zhang, Jingyu; Wu, Meiping; Li, Tao; Zhang, Kaidong

2015-11-01

In the high-precision application of Global Navigation Satellite System (GNSS), integer ambiguity resolution is the key step to realize precise positioning and attitude determination. As the necessary part of quality control, integer aperture (IA) ambiguity resolution provides the theoretical and practical foundation for ambiguity validation. It is mainly realized by acceptance testing. Due to the constraint of correlation between ambiguities, it is impossible to realize the controlling of failure rate according to analytical formula. Hence, the fixed failure rate approach is implemented by Monte Carlo sampling. However, due to the characteristics of Monte Carlo sampling and look-up table, we have to face the problem of a large amount of time consumption if sufficient GNSS scenarios are included in the creation of look-up table. This restricts the fixed failure rate approach to be a post process approach if a look-up table is not available. Furthermore, if not enough GNSS scenarios are considered, the table may only be valid for a specific scenario or application. Besides this, the method of creating look-up table or look-up function still needs to be designed for each specific acceptance test. To overcome these problems in determination of critical values, this contribution will propose an instantaneous and CONtrollable (iCON) IA ambiguity resolution approach for the first time. The iCON approach has the following advantages: (a) critical value of acceptance test is independently determined based on the required failure rate and GNSS model without resorting to external information such as look-up table; (b) it can be realized instantaneously for most of IA estimators which have analytical probability formulas. The stronger GNSS model, the less time consumption; (c) it provides a new viewpoint to improve the research about IA estimation. To verify these conclusions, multi-frequency and multi-GNSS simulation experiments are implemented. Those results show that IA

Ambiguity Within Nursing Practice: An Evolutionary Concept Analysis.

Science.gov (United States)

McMahon, Michelle A; Dluhy, Nancy M

2017-02-01

To analyze the concept of ambiguity in a nursing context. Ambiguity is inherent within nursing practice. As health care becomes increasingly complex, nurses must continue to successfully deal with greater amounts of clinical ambiguity. Although ambiguity is discussed in nursing, minimal concept refinement exists to capture the contextual intricacies from a nursing lens. Nurse perception of an ambiguous clinical event, in combination with nurse tolerance level for ambiguity, can impact nurse response. Yet, little is known about what constitutes ambiguity within nursing practice (AWNP). Rodgers evolutionary method was used to explore AWNP, with emphasis on nurse thinking during ambiguous clinical situations. Literature searches across multiple databases yielded 38 articles for analysis. Attributes of AWNP include (a) variations in cues/available information, (b) multiple interpretations, (c) novel/nonroutine presentations, and (d) unpredictable. Antecedents include (a) a context-specific, clinical situation with ambiguous features needing evaluation and (b) an individual to sense a knowledge gap or perceive ambiguity. Consequences include ranges of (a) emotional, (b) behavioral, and (c) cognitive clinician responses. Preliminary findings support AWNP as a distinct concept in which ambiguity perceived by the nurse likely affects judgment, decision making, and clinical interventions. AWNP is a clinically relevant concept requiring continued development.

Probability judgments under ambiguity and conflict.

Science.gov (United States)

Smithson, Michael

2015-01-01

Whether conflict and ambiguity are distinct kinds of uncertainty remains an open question, as does their joint impact on judgments of overall uncertainty. This paper reviews recent advances in our understanding of human judgment and decision making when both ambiguity and conflict are present, and presents two types of testable models of judgments under conflict and ambiguity. The first type concerns estimate-pooling to arrive at "best" probability estimates. The second type is models of subjective assessments of conflict and ambiguity. These models are developed for dealing with both described and experienced information. A framework for testing these models in the described-information setting is presented, including a reanalysis of a multi-nation data-set to test best-estimate models, and a study of participants' assessments of conflict, ambiguity, and overall uncertainty reported by Smithson (2013). A framework for research in the experienced-information setting is then developed, that differs substantially from extant paradigms in the literature. This framework yields new models of "best" estimates and perceived conflict. The paper concludes with specific suggestions for future research on judgment and decision making under conflict and ambiguity.

Renormalon ambiguities in NRQCD operator matrix elements

International Nuclear Information System (INIS)

Bodwin, G.T.; Chen, Y.

1999-01-01

We analyze the renormalon ambiguities that appear in factorization formulas in QCD. Our analysis contains a simple argument that the ambiguities in the short-distance coefficients and operator matrix elements are artifacts of dimensional-regularization factorization schemes and are absent in cutoff schemes. We also present a method for computing the renormalon ambiguities in operator matrix elements and apply it to a computation of the ambiguities in the matrix elements that appear in the NRQCD factorization formulas for the annihilation decays of S-wave quarkonia. Our results, combined with those of Braaten and Chen for the short-distance coefficients, provide an explicit demonstration that the ambiguities cancel in the physical decay rates. In addition, we analyze the renormalon ambiguities in the Gremm-Kapustin relation and in various definitions of the heavy-quark mass. copyright 1999 The American Physical Society

Neural Correlates of Decision-Making Under Ambiguity and Conflict.

Science.gov (United States)

Pushkarskaya, Helen; Smithson, Michael; Joseph, Jane E; Corbly, Christine; Levy, Ifat

2015-01-01

HIGHLIGHTS We use a simple gambles design in an fMRI study to compare two conditions: ambiguity and conflict.Participants were more conflict averse than ambiguity averse.Ambiguity aversion did not correlate with conflict aversion.Activation in the medial prefrontal cortex correlated with ambiguity level and ambiguity aversion.Activation in the ventral striatum correlated with conflict level and conflict aversion. Studies of decision making under uncertainty generally focus on imprecise information about outcome probabilities ("ambiguity"). It is not clear, however, whether conflicting information about outcome probabilities affects decision making in the same manner as ambiguity does. Here we combine functional magnetic resonance imaging (fMRI) and a simple gamble design to study this question. In this design the levels of ambiguity and conflict are parametrically varied, and ambiguity and conflict gambles are matched on expected value. Behaviorally, participants avoided conflict more than ambiguity, and attitudes toward ambiguity and conflict did not correlate across participants. Neurally, regional brain activation was differentially modulated by ambiguity level and aversion to ambiguity and by conflict level and aversion to conflict. Activation in the medial prefrontal cortex was correlated with the level of ambiguity and with ambiguity aversion, whereas activation in the ventral striatum was correlated with the level of conflict and with conflict aversion. These novel results indicate that decision makers process imprecise and conflicting information differently, a finding that has important implications for basic and clinical research.

Reactive agents and perceptual ambiguity

NARCIS (Netherlands)

Dartel, M. van; Sprinkhuizen-Kuyper, I.G.; Postma, E.O.; Herik, H.J. van den

2005-01-01

Reactive agents are generally believed to be incapable of coping with perceptual ambiguity (i.e., identical sensory states that require different responses). However, a recent finding suggests that reactive agents can cope with perceptual ambiguity in a simple model (Nolfi, 2002). This paper

Perspective on energy security and other non environmental externalities in electricity generation

International Nuclear Information System (INIS)

Bohi, D.R.

1994-01-01

Applications of the term externality to non environmental matters are often controversial and ambiguous. This paper argues that these externalities are also rarer or less important than sometimes alleged. The paper examines various potential energy security externalities and concludes that none of them are relevant to decisions regarding electric generation. Externalities may exist with regard to effects on local employment and the local infrastructure, although their importance is location specific and their measurement is highly subjective. In short, the consideration of this subset of externalities may confuse policy makers more than it helps them. (author). 15 refs

Alcohol reduces aversion to ambiguity

Directory of Open Access Journals (Sweden)

Tadeusz eTyszka

2015-01-01

Full Text Available Several years ago, Cohen, Dearnaley, and Hansel [1] demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly [2]. The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar, where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

Alcohol reduces aversion to ambiguity.

Science.gov (United States)

Tyszka, Tadeusz; Macko, Anna; Stańczak, Maciej

2014-01-01

Several years ago, Cohen et al. (1958) demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly (Camerer and Weber, 1992). The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar), where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

The Functional Significance of Chiral Genitalia: Patterns of Asymmetry, Functional Morphology and Mating Success in the Praying Mantis Ciulfina baldersoni.

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Gregory I Holwell

Full Text Available Genital asymmetry is relatively common and widespread throughout the animal kingdom. The functional significance of genital asymmetry is however, poorly understood for most species. Male praying mantids of the genus Ciulfina are remarkable in possessing complex and directionally asymmetric genital phallomeres in some species, and chirally dimorphic/antisymmetric genitalia in others. Here we explore the chiral dimorphism in male genitalia of Ciulfina baldersoni which appear to exhibit genital antisymmetry. We test whether genital orientation influences mating success, copulation duration and the attachment duration of spermatophores. Additionally we investigate genital interactions between male and females using x-ray micro-computed tomography (micro-CT and scanning electron microscopy (SEM. Lastly we assess whether genital asymmetry is associated with non-genital morphological asymmetry of a range of traits. Our results highlight the complex functional morphology of genitalia in this praying mantis species and yet demonstrate no functional difference between dextral and sinistral morphs other than the direction of attachment with both morphs enjoying equal levels of mating success. Chiral morphs also did not strongly associate with any other forms of asymmetry. We therefore conclude that genital chirality in Ciulfina baldersoni is a likely case of antisymmetry with no functional significance to genital orientation, and is likely to be selectively neutral.

Risk, Ambiguity, and Insurance.

Science.gov (United States)

1984-10-01

California felt that once a severe earthquake occurs, it is le likely to occur in the near future (Kunreuther et al., 1978). When probabilities are...psychological model of how people assess probabilities In ambiguous circumstances. This model is based on three principles : (1) In assessing an ambiguous...TECHNICAL REPORTS DISTRIBUTION LIST 050 Department of the Navy CAPT Paul R. Chatelier Dr. Andrew Rachnitser Office of the Deputy Under Secretary Office of

Recommendations for reducing ambiguity in written procedures.

Energy Technology Data Exchange (ETDEWEB)

Matzen, Laura E.

2009-11-01

Previous studies in the nuclear weapons complex have shown that ambiguous work instructions (WIs) and operating procedures (OPs) can lead to human error, which is a major cause for concern. This report outlines some of the sources of ambiguity in written English and describes three recommendations for reducing ambiguity in WIs and OPs. The recommendations are based on commonly used research techniques in the fields of linguistics and cognitive psychology. The first recommendation is to gather empirical data that can be used to improve the recommended word lists that are provided to technical writers. The second recommendation is to have a review in which new WIs and OPs and checked for ambiguities and clarity. The third recommendation is to use self-paced reading time studies to identify any remaining ambiguities before the new WIs and OPs are put into use. If these three steps are followed for new WIs and OPs, the likelihood of human errors related to ambiguity could be greatly reduced.

The Ethics of Strategic Ambiguity.

Science.gov (United States)

Paul, Jim; Strbiak, Christy A.

1997-01-01

Examines the concept of strategic ambiguity in communication, and addresses the ethics of strategic ambiguity from an intrapersonal perspective that considers the congruity of communicators' espoused-ethics, ethics-in-use, and behavior, where ethical judgements are based on the congruity between espoused-ethics and actual behavior. Poses questions…

Quantization ambiguity, ergodicity and semiclassics

International Nuclear Information System (INIS)

Kaplan, Lev

2002-01-01

It is well known that almost all eigenstates of a classically ergodic system are individually ergodic on coarse-grained scales. This has important implications for the quantization ambiguity in ergodic systems: the difference between alternative quantizations is suppressed compared with the O( h-bar 2 ) ambiguity in the integrable or regular case. For two-dimensional ergodic systems in the high-energy regime, individual eigenstates are independent of the choice of quantization procedure, in contrast with the regular case, where even the ordering of eigenlevels is ambiguous. Surprisingly, semiclassical methods are shown to be much more precise in any dimension for chaotic than for integrable systems

Semi-classical analysis of optical model ambiguities

International Nuclear Information System (INIS)

Cuer, M.

1979-01-01

The ambiguities in the inverse problem at fixed energy in quantum mechanics are analyzed in the framework of the JWKB method. When the classical turning point is unique for all values of the impact parameter (high energies region), the ambiguities proceed only from the quantization of the angular momentum. In the asymptotic region the difference between two particular equivalent potentials changes sign infinitely often. In addition, the set of equivalent potentials which have a given asymptotic form is bounded (except perhaps at the origin). When there are several turning points for small values of the impact parameter (low-energy region), new ambiguities arise from the fact that the parts of the potential that are located between turning points are not ''visible'' in the classical limit. The set of equivalent potentials wich have a given asymptotic form is then not bounded. Mumerical examples (of real and complex equivalent potentials) are given. The optical model ambiguities are studied. The potential depth ambiguities also appear in classical mechanics, but their discrete nature is a quantum property. The VR/sup p//sup( V/)=constant ambiguities can be explained by the quantum corrections to the spiral scattering phenomenon. An attempt to explain why ambiguities arise only with heavy particles scattering is also given

Ambiguous walls

DEFF Research Database (Denmark)

Mody, Astrid

2012-01-01

The introduction of Light Emitting Diodes (LEDs) in the built environment has encouraged myriad applications, often embedded in surfaces as an integrated part of the architecture. Thus the wall as responsive luminous skin is becoming, if not common, at least familiar. Taking into account how walls...... have encouraged architectural thinking of enclosure, materiality, construction and inhabitation in architectural history, the paper’s aim is to define new directions for the integration of LEDs in walls, challenging the thinking of inhabitation and program. This paper introduces the notion...... of “ambiguous walls” as a more “critical” approach to design [1]. The concept of ambiguous walls refers to the diffuse status a lumious and possibly responsive wall will have. Instead of confining it can open up. Instead of having a static appearance, it becomes a context over time. Instead of being hard...

Variations in the male genitalia of Aedes (Stegomyia Albopictus (Skuse from Chandigarh and its surrounding areas (Diptera: Culicidae

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Sagandeep Kaur

2014-09-01

Full Text Available The Asian tiger mosquito Aedes albopictus is the most dominant species of subgenus Stegomyia and is medically important from the standpoint of transmitting wide range of human pathogens of deadly diseases like dengue, yellow fever and chikungunya. During present investigations, it has been observed that IX tergum in the male genitalia of Aedes albopictus varies greatly. It shows variations with respect to the presence or absence of lateral projections on the IX tergum, as well as in the shape and size of median and lateral projections. The shape of IX tergum in the male genitalia of Aedes species is of great taxonomic importance as it is a diagnostic character of the species. These variations have been observed both in natural populations collected from various breeding sites as well as in the adults reared in laboratory. The observed differences have not been noticed by any of the previous workers.

Symbol in Point View of Ambiguity

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Dr. M. R. Yousefi

Full Text Available Symbol from the perspective of rhetorical word, is phrase or sentence that apparent meaning, also inspires to reader a wide range of semantic.Since exploring the complex social and political ideas in the most mysticalway and indirectreflectionsocial and political thoughts symbolically is easier, so the symbol and symbolism especially in Persian literatureespeciallyin the realm of Persian poetry, has a special appearance.In addition to the factors mentioned in the contemporary literature, according familiar in literature and the emergence of particular schools interest toambiguoussymbolization has spreadfurther, especially the symbol has all the features of art ambiguity in the poem and it isone the major factors causing uncertainty.Thus, the precise definitions and symbols of contemporary poetry could be dominant in the unwinding ambiguous symbol detection of cryptic allusions and metaphors that matches the cursor symbol to help readers.In the literature, especially language poetry, the inability of language toreflecting obscure mystical ideas, avoid to directexpression of political and social concerns of the reader in the course of participate to creation ambiguous literary works is the main motivation towards symbol and symbolization.According widespread use of symbol and its different of species can be viewed from different perspectives.The creation of ambiguity is the main purposes of using symbols (especially in poetry, so many poets have tried to achieve this goal have to formation of similar symbols and the explanation and resolution of this issue can open new window for understanding the poetry in front of an audience.In this paper examines the ambiguity of symbols in terms of its precise boundaries are reviewed. Ambiguity is one of the important processes and also is the key Iranian poetry; its means is today poetry. In such poetry ambiguity is a need to explore the new world from a different perspective, or explore this complex world

Gauge-fixing ambiguity and monopole number

International Nuclear Information System (INIS)

Hioki, S.; Miyamura, O.

1991-01-01

Gauge-fixing ambiguities of lattice SU(2) QCD are studied in the maximally abelian and unitary gauges. In the former, we find local maxima of a gauge-fixing function which may correspond to Gribov copies. There is a definite anti-correlation between the number of monopoles and the value of the function. Errors of measured quantities coming from the ambiguity are found to be less than inherent dispersion in the ensemble average. No ambiguity is found in the unitary gauges. (orig.)

Ambiguous Adaptation

DEFF Research Database (Denmark)

Møller Larsen, Marcus; Lyngsie, Jacob

and reciprocal adaptation of informal governance structure create ambiguity in situations of contingencies, which, subsequently, increases the likelihood of premature relationship termination. Using a large sample of exchange relationships in the global service provider industry, we find support for a hypothesis...

Eliminating ambiguity in digital signals

Science.gov (United States)

Weber, W. J., III

1979-01-01

Multiamplitude minimum shift keying (mamsk) transmission system, method of differential encoding overcomes problem of ambiguity associated with advanced digital-transmission techniques with little or no penalty in transmission rate, error rate, or system complexity. Principle of method states, if signal points are properly encoded and decoded, bits are detected correctly, regardless of phase ambiguities.

Productive Ambiguity in the Learning of Mathematics

Science.gov (United States)

Foster, Colin

2011-01-01

In this paper I take a positive view of ambiguity in the learning of mathematics. Following Grosholz (2007), I argue that it is not only the arts which exploit ambiguity for creative ends but science and mathematics too. By enabling the juxtaposition of multiple conflicting frames of reference, ambiguity allows novel connections to be made. I…

The evolution of asymmetric genitalia in Coleoptera.

Science.gov (United States)

Schilthuizen, Menno; de Jong, Paulien; van Beek, Rick; Hoogenboom, Tamara; Schlochtern, Melanie Meijer Zu

2016-12-19

The evolution of asymmetry in male genitalia is a pervasive and recurrent phenomenon across almost the entire animal kingdom. Although in some taxa the asymmetry may be a response to the evolution of one-sided, male-above copulation from a more ancestral female-above condition, in other taxa, such as Mammalia and Coleoptera, this explanation appears insufficient. We carried out an informal assessment of genital asymmetry across the Coleoptera and found that male genital asymmetry is present in 43% of all beetle families, and at all within-family taxonomic levels. In the most diverse group, Cucujiformia, however, genital asymmetry is comparatively rare. We also reconstructed the phylogeny of the leiodid tribe Cholevini, and mapped aspects of genital asymmetry on the tree, revealing that endophallus sclerites, endophallus, median lobe and parameres are, in a nested fashion, increasingly unlikely to have evolved asymmetry. We interpret these results in the light of cryptic female choice versus sexually antagonistic coevolution and advocate further ways in which the phenomenon may be better understood.This article is part of the themed issue 'Provocative questions in left-right asymmetry'. © 2016 The Authors.

Ambiguous Intimacy

DEFF Research Database (Denmark)

Houmøller, Kathrin

2015-01-01

relations and intimacy is riddled with inevitability and precarity. Here, it is argued, intimacy is ambiguous: allowed and resisted, longed for and feared - simultaneously encompassing practices of closeness and distance, connecting and disconnecting. To make a life in this particular place sometimes...

Ontology: ambiguity and accuracy

Directory of Open Access Journals (Sweden)

Marcelo Schiessl

2012-08-01

Full Text Available Ambiguity is a major obstacle to information retrieval. It is source of several researches in Information Science. Ontologies have been studied in order to solve problems related to ambiguities. Paradoxically, “ontology” term is also ambiguous and it is understood according to the use by the community. Philosophy and Computer Science seems to have the most accentuated difference related to the term sense. The former holds undisputed tradition and authority. The latter, in despite of being quite recent, holds an informal sense, but pragmatic. Information Science acts ranging from philosophical to computational approaches so as to get organized collections based on balance between users’ necessities and available information. The semantic web requires informational cycle automation and demands studies related to ontologies. Consequently, revisiting relevant approaches for the study of ontologies plays a relevant role as a way to provide useful ideas to researchers maintaining philosophical rigor, and convenience provided by computers.

Analyzing Ambiguity of Context-Free Grammars

DEFF Research Database (Denmark)

Brabrand, Claus; Giegerich, Robert; Møller, Anders

2007-01-01

It has been known since 1962 that the ambiguity problem for context-free grammars is undecidable. Ambiguity in context-free grammars is a recurring problem in language design and parser generation, as well as in applications where grammars are used as models of real-world physical structures. We...... observe that there is a simple linguistic characterization of the grammar ambiguity problem, and we show how to exploit this to conservatively approximate the problem based on local regular approximations and grammar unfoldings. As an application, we consider grammars that occur in RNA analysis...

Perturbative ambiguities in Coulomb gauge QCD

International Nuclear Information System (INIS)

Doust, P.

1987-01-01

The naive Coulomb gauge Feynman rules in non-abelian gauge theory give rise to ambiguous integrals, in addition to the usual ultraviolet divergences. Generalizing the work of Cheng and Tsai, these ambiguities are resolved to all orders in perturbation theory, by defining a gauge that interpolates smoothly between the Feynman gauge and the Coulomb gauge. The extra terms V 1 +V 2 of Christ and Lee are identified with certain two-loop ambiguous terms. However, there still seem to be unsolved problems connected with renormalisation. copyright 1987 Academic Press, Inc

Taxonomic notes on Amarodytes duponti (Aubé, 1838 (Dytiscidae, Hydroporinae, Bidessini with redescription of male genitalia

Directory of Open Access Journals (Sweden)

Benetti, C. J.

2004-12-01

Full Text Available The male genitalia of the water beetle Amarodytes duponti (Aubé, 1838 are described and illustrated. The species was collectedin small pools of rainwater on the margins of a river. A. duponti is distinguished from other species of the genus by the presence of bi-segmented parameres. This species is related to Bidessodes Régimbart, Hypodessus Guignot and Tepuidessus Spangler.

Genetic architecture and functional characterization of genes underlying the rapid diversification of male external genitalia between Drosophila simulans and Drosophila mauritiana.

Science.gov (United States)

Tanaka, Kentaro M; Hopfen, Corinna; Herbert, Matthew R; Schlötterer, Christian; Stern, David L; Masly, John P; McGregor, Alistair P; Nunes, Maria D S

2015-05-01

Male sexual characters are often among the first traits to diverge between closely related species and identifying the genetic basis of such changes can contribute to our understanding of their evolutionary history. However, little is known about the genetic architecture or the specific genes underlying the evolution of male genitalia. The morphology of the claspers, posterior lobes, and anal plates exhibit striking differences between Drosophila mauritiana and D. simulans. Using QTL and introgression-based high-resolution mapping, we identified several small regions on chromosome arms 3L and 3R that contribute to differences in these traits. However, we found that the loci underlying the evolution of clasper differences between these two species are independent from those that contribute to posterior lobe and anal plate divergence. Furthermore, while most of the loci affect each trait in the same direction and act additively, we also found evidence for epistasis between loci for clasper bristle number. In addition, we conducted an RNAi screen in D. melanogaster to investigate if positional and expression candidate genes located on chromosome 3L, are also involved in genital development. We found that six of these genes, including components of Wnt signaling and male-specific lethal 3 (msl3), regulate the development of genital traits consistent with the effects of the introgressed regions where they are located and that thus represent promising candidate genes for the evolution these traits. Copyright © 2015 by the Genetics Society of America.

Ambiguity and Volatility : Asset Pricing Implications

NARCIS (Netherlands)

Pataracchia, B.

2011-01-01

Using a simple dynamic consumption-based asset pricing model, this paper explores the implications of a representative investor with smooth ambiguity averse preferences [Klibano¤, Marinacci and Mukerji, Econometrica (2005)] and provides a comparative analysis of risk aversion and ambiguity aversion.

Ambiguity attitudes in decisions for others

NARCIS (Netherlands)

König-Kersting, Christian; Trautmann, Stefan

We probe the pattern of ambiguity aversion for moderate-likelihood gain prospects, and ambiguity seeking for low-likelihood gain prospects, if people make decisions not for themselves but as agents for others. We confirm the pattern both with and without accountability.

Gene name ambiguity of eukaryotic nomenclatures.

Science.gov (United States)

Chen, Lifeng; Liu, Hongfang; Friedman, Carol

2005-01-15

With more and more scientific literature published online, the effective management and reuse of this knowledge has become problematic. Natural language processing (NLP) may be a potential solution by extracting, structuring and organizing biomedical information in online literature in a timely manner. One essential task is to recognize and identify genomic entities in text. 'Recognition' can be accomplished using pattern matching and machine learning. But for 'identification' these techniques are not adequate. In order to identify genomic entities, NLP needs a comprehensive resource that specifies and classifies genomic entities as they occur in text and that associates them with normalized terms and also unique identifiers so that the extracted entities are well defined. Online organism databases are an excellent resource to create such a lexical resource. However, gene name ambiguity is a serious problem because it affects the appropriate identification of gene entities. In this paper, we explore the extent of the problem and suggest ways to address it. We obtained gene information from 21 organisms and quantified naming ambiguities within species, across species, with English words and with medical terms. When the case (of letters) was retained, official symbols displayed negligible intra-species ambiguity (0.02%) and modest ambiguities with general English words (0.57%) and medical terms (1.01%). In contrast, the across-species ambiguity was high (14.20%). The inclusion of gene synonyms increased intra-species ambiguity substantially and full names contributed greatly to gene-medical-term ambiguity. A comprehensive lexical resource that covers gene information for the 21 organisms was then created and used to identify gene names by using a straightforward string matching program to process 45,000 abstracts associated with the mouse model organism while ignoring case and gene names that were also English words. We found that 85.1% of correctly retrieved mouse

Does ambiguity aversion survive in experimental asset markets?

NARCIS (Netherlands)

Füllbrunn, Sascha; Rau, Holger A.; Weitzel, Utz

2014-01-01

Although a number of theoretical studies explain empirical puzzles in finance with ambiguity aversion, it is not a given that individual ambiguity attitudes survive in markets. In fact, despite ample evidence of ambiguity aversion in individual decision making, most studies find no or only limited

Ambiguities and conventions in the perception of visual art.

Science.gov (United States)

Mamassian, Pascal

2008-09-01

Vision perception is ambiguous and visual arts play with these ambiguities. While perceptual ambiguities are resolved with prior constraints, artistic ambiguities are resolved by conventions. Is there a relationship between priors and conventions? This review surveys recent work related to these ambiguities in composition, spatial scale, illumination and color, three-dimensional layout, shape, and movement. While most conventions seem to have their roots in perceptual constraints, those conventions that differ from priors may help us appreciate how visual arts differ from everyday perception.

Equity Trading under Heterogeneity in Ambiguity

DEFF Research Database (Denmark)

Alonso, Irasema; Prado, Mauricio

-relevant, but hard-to-interpret information: a situation like that during the onset of the recent crisis in financial markets. During this episode, market participants appeared unsure of the values of a variety of assets, trading all but stopped. Ambiguity aversion, it appears to us, offers a tractable way......-participation - a drastic form of trading less - in the ambiguity-ridden market by certain agents (here we have in mind those with higher levels of ambiguity). This endogenous limited participation on the market also has implications for the relative wealth of agents in an economy. The dynamics of the wealth distribution...

Precise Point Positioning with Partial Ambiguity Fixing.

Science.gov (United States)

Li, Pan; Zhang, Xiaohong

2015-06-10

Reliable and rapid ambiguity resolution (AR) is the key to fast precise point positioning (PPP). We propose a modified partial ambiguity resolution (PAR) method, in which an elevation and standard deviation criterion are first used to remove the low-precision ambiguity estimates for AR. Subsequently the success rate and ratio-test are simultaneously used in an iterative process to increase the possibility of finding a subset of decorrelated ambiguities which can be fixed with high confidence. One can apply the proposed PAR method to try to achieve an ambiguity-fixed solution when full ambiguity resolution (FAR) fails. We validate this method using data from 450 stations during DOY 021 to 027, 2012. Results demonstrate the proposed PAR method can significantly shorten the time to first fix (TTFF) and increase the fixing rate. Compared with FAR, the average TTFF for PAR is reduced by 14.9% for static PPP and 15.1% for kinematic PPP. Besides, using the PAR method, the average fixing rate can be increased from 83.5% to 98.2% for static PPP, from 80.1% to 95.2% for kinematic PPP respectively. Kinematic PPP accuracy with PAR can also be significantly improved, compared to that with FAR, due to a higher fixing rate.

Semantic Ambiguity Effects in L2 Word Recognition.

Science.gov (United States)

Ishida, Tomomi

2018-06-01

The present study examined the ambiguity effects in second language (L2) word recognition. Previous studies on first language (L1) lexical processing have observed that ambiguous words are recognized faster and more accurately than unambiguous words on lexical decision tasks. In this research, L1 and L2 speakers of English were asked whether a letter string on a computer screen was an English word or not. An ambiguity advantage was found for both groups and greater ambiguity effects were found for the non-native speaker group when compared to the native speaker group. The findings imply that the larger ambiguity advantage for L2 processing is due to their slower response time in producing adequate feedback activation from the semantic level to the orthographic level.

Processing subject-object ambiguities in Dutch

NARCIS (Netherlands)

Kaan, Edith

1997-01-01

Various clause types in Dutch and German are at least temporarily ambiguous with respect to the order of subject and object. A number of previous studies regarding the processing of such subject-object ambiguities have reported a preference for a subject-object interpretation. This order preference

SAR Ambiguity Study for the Cassini Radar

Science.gov (United States)

Hensley, Scott; Im, Eastwood; Johnson, William T. K.

1993-01-01

The Cassini Radar's synthetic aperture radar (SAR) ambiguity analysis is unique with respect to other spaceborne SAR ambiguity analyses owing to the non-orbiting spacecraft trajectory, asymmetric antenna pattern, and burst mode of data collection. By properly varying the pointing, burst mode timing, and radar parameters along the trajectory this study shows that the signal-to-ambiguity ratio of better than 15 dB can be achieved for all images obtained by the Cassini Radar.

Ultrasound -- Pelvis

Medline Plus

Full Text Available ... diagnose symptoms experienced by women such as: pelvic pain abnormal vaginal bleeding other menstrual problems Ultrasound exams ... pelvic ultrasound can help evaluate: pelvic masses pelvic pain ambiguous genitalia and anomalies of pelvic organs early ...

Ultrasound -- Pelvis

Medline Plus

Full Text Available ... menstrual problems Ultrasound exams also help identify: palpable masses such as ovarian cysts and uterine fibroids ovarian ... In children, pelvic ultrasound can help evaluate: pelvic masses pelvic pain ambiguous genitalia and anomalies of pelvic ...

Ultrasound -- Pelvis

Medline Plus

Full Text Available ... pain ambiguous genitalia and anomalies of pelvic organs early or delayed puberty in girls Pelvic ultrasound is ... sensitive to motion, and an active or crying child can prolong the examination process. To ensure a ...

Regularization ambiguities in loop quantum gravity

International Nuclear Information System (INIS)

Perez, Alejandro

2006-01-01

One of the main achievements of loop quantum gravity is the consistent quantization of the analog of the Wheeler-DeWitt equation which is free of ultraviolet divergences. However, ambiguities associated to the intermediate regularization procedure lead to an apparently infinite set of possible theories. The absence of an UV problem--the existence of well-behaved regularization of the constraints--is intimately linked with the ambiguities arising in the quantum theory. Among these ambiguities is the one associated to the SU(2) unitary representation used in the diffeomorphism covariant 'point-splitting' regularization of the nonlinear functionals of the connection. This ambiguity is labeled by a half-integer m and, here, it is referred to as the m ambiguity. The aim of this paper is to investigate the important implications of this ambiguity. We first study 2+1 gravity (and more generally BF theory) quantized in the canonical formulation of loop quantum gravity. Only when the regularization of the quantum constraints is performed in terms of the fundamental representation of the gauge group does one obtain the usual topological quantum field theory as a result. In all other cases unphysical local degrees of freedom arise at the level of the regulated theory that conspire against the existence of the continuum limit. This shows that there is a clear-cut choice in the quantization of the constraints in 2+1 loop quantum gravity. We then analyze the effects of the ambiguity in 3+1 gravity exhibiting the existence of spurious solutions for higher representation quantizations of the Hamiltonian constraint. Although the analysis is not complete in 3+1 dimensions - due to the difficulties associated to the definition of the physical inner product - it provides evidence supporting the definitions quantum dynamics of loop quantum gravity in terms of the fundamental representation of the gauge group as the only consistent possibilities. If the gauge group is SO(3) we find

46,XX Karyotype in a Male with Ambigious Genitalia: A Case Report

Directory of Open Access Journals (Sweden)

Mahmut Balkan

2004-01-01

Full Text Available 40 days old case who were diagnosed with ambigious genitalia were sentto laboratory of cytogenetics. Mother was 26 years old and have to alivechildren and case were the second child and applied to Child SurgeryDepartment due to continiously vomiting and uneasy conditions. Sexualdevelopment were as male on physical examinations. Cell culture wasapplied for chromosomal analysis. Slides were stained with GiemsaBanding Staining (GTG and 100 cells were totaly counted and karyotypingwere done with 15 metaphase. Chromosome with 46,XX karyotype. Casewere taken under consideration of congenital adrenel hyperplasia afterevalution of karyotype. Case were discussed according to by information ofpresents literatures.

Ambiguity and violence in adolescent dating relationships.

Science.gov (United States)

Draucker, Claire Burke; Martsolf, Donna; Stephenson, Pam Shockey

2012-08-01

Little is known about dyadic processes that lead to adolescent dating violence. The purpose of this study was to examine the phenomenon of relationship ambiguity in adolescent dating relationships to better understand how ambiguity contributes to violence and aggression between dating partners. Data were drawn from 88 narratives of young adults who had participated in a study on adolescent dating violence. Interpretive phenomenology was used to produce an in-depth description of the phenomenon of relationship ambiguity. Relationship ambiguity results in differing expectations between partners regarding closeness and intimacy, fidelity, and obligation. These differences lead to conflicts that set the stage for violence and aggression in adolescent dating relationships. A series of recommendations for clinicians working with adolescents are presented. © 2012 Wiley Periodicals, Inc.

Potential Ambiguity Translation Performances within Legal Language Institutional Nomenclature

Directory of Open Access Journals (Sweden)

Oţăt Diana

2015-12-01

Full Text Available Motivated by a paradoxical corollary of ambiguities in legal documents and especially in contract texts, the current paper underpins a dichotomy approach to unintended ambiguities aiming to establish a referential framework for the occurrence rate of translation ambiguities within the legal language nomenclature. The research focus is on a twofold situation since ambiguities may. on the one hand, arise dining the translation process, generated by the translator’s lack of competence, i.e. inadequate use of English regarding the special nature of legal language, or. on the other hand, they may be simply transferred from the source language into the target language without even noticing the potential ambiguous situation, i.e. culture-bound ambiguities. Hence, the paper proposes a contrastive analysis in order to localize the occurrence of lexical, structural, and socio-cultural ambiguities triggered by the use of the term performance and its Romanian equivalents in a number of sales contracts.

Combined GPS/GLONASS Precise Point Positioning with Fixed GPS Ambiguities

Science.gov (United States)

Pan, Lin; Cai, Changsheng; Santerre, Rock; Zhu, Jianjun

2014-01-01

Precise point positioning (PPP) technology is mostly implemented with an ambiguity-float solution. Its performance may be further improved by performing ambiguity-fixed resolution. Currently, the PPP integer ambiguity resolutions (IARs) are mainly based on GPS-only measurements. The integration of GPS and GLONASS can speed up the convergence and increase the accuracy of float ambiguity estimates, which contributes to enhancing the success rate and reliability of fixing ambiguities. This paper presents an approach of combined GPS/GLONASS PPP with fixed GPS ambiguities (GGPPP-FGA) in which GPS ambiguities are fixed into integers, while all GLONASS ambiguities are kept as float values. An improved minimum constellation method (MCM) is proposed to enhance the efficiency of GPS ambiguity fixing. Datasets from 20 globally distributed stations on two consecutive days are employed to investigate the performance of the GGPPP-FGA, including the positioning accuracy, convergence time and the time to first fix (TTFF). All datasets are processed for a time span of three hours in three scenarios, i.e., the GPS ambiguity-float solution, the GPS ambiguity-fixed resolution and the GGPPP-FGA resolution. The results indicate that the performance of the GPS ambiguity-fixed resolutions is significantly better than that of the GPS ambiguity-float solutions. In addition, the GGPPP-FGA improves the positioning accuracy by 38%, 25% and 44% and reduces the convergence time by 36%, 36% and 29% in the east, north and up coordinate components over the GPS-only ambiguity-fixed resolutions, respectively. Moreover, the TTFF is reduced by 27% after adding GLONASS observations. Wilcoxon rank sum tests and chi-square two-sample tests are made to examine the significance of the improvement on the positioning accuracy, convergence time and TTFF. PMID:25237901

Combined GPS/GLONASS Precise Point Positioning with Fixed GPS Ambiguities

Directory of Open Access Journals (Sweden)

Lin Pan

2014-09-01

Full Text Available Precise point positioning (PPP technology is mostly implemented with an ambiguity-float solution. Its performance may be further improved by performing ambiguity-fixed resolution. Currently, the PPP integer ambiguity resolutions (IARs are mainly based on GPS-only measurements. The integration of GPS and GLONASS can speed up the convergence and increase the accuracy of float ambiguity estimates, which contributes to enhancing the success rate and reliability of fixing ambiguities. This paper presents an approach of combined GPS/GLONASS PPP with fixed GPS ambiguities (GGPPP-FGA in which GPS ambiguities are fixed into integers, while all GLONASS ambiguities are kept as float values. An improved minimum constellation method (MCM is proposed to enhance the efficiency of GPS ambiguity fixing. Datasets from 20 globally distributed stations on two consecutive days are employed to investigate the performance of the GGPPP-FGA, including the positioning accuracy, convergence time and the time to first fix (TTFF. All datasets are processed for a time span of three hours in three scenarios, i.e., the GPS ambiguity-float solution, the GPS ambiguity-fixed resolution and the GGPPP-FGA resolution. The results indicate that the performance of the GPS ambiguity-fixed resolutions is significantly better than that of the GPS ambiguity-float solutions. In addition, the GGPPP-FGA improves the positioning accuracy by 38%, 25% and 44% and reduces the convergence time by 36%, 36% and 29% in the east, north and up coordinate components over the GPS-only ambiguity-fixed resolutions, respectively. Moreover, the TTFF is reduced by 27% after adding GLONASS observations. Wilcoxon rank sum tests and chi-square two-sample tests are made to examine the significance of the improvement on the positioning accuracy, convergence time and TTFF.

Trauma Outcomes and UroGenital Health in OEF/OIF (TOUGH) - A Retrospective Cohort Study with Long-Term Follow-up

Science.gov (United States)

2017-07-01

majority involved the external genitalia (n=1,000, 73.2%), including the scrotum (760, 55.6%), testes (451, 33.0%), penis (423, 31%) and/or urethra (125...genitourinary injuries; the majority involved the external genitalia (n=1,000, 73.2%), including the scrotum (760, 55.6%), testes (451, 33.0%), penis (423

Concept analysis: Role ambiguity in senior nursing students.

Science.gov (United States)

Kalkman, Beth

2018-04-01

Role ambiguity is a lack of clarity or uncertainty related to one's position or role. Role ambiguity has been documented in the literature in relationship to athletics, industry, business, education, and nursing. However, a concept analysis has not been performed. Therefore, the process of concept analysis outlined by Walker and Avant is now used to look at the concept of role ambiguity and its relevance to senior nursing students' socialization and education into the profession of nursing. Attributes, antecedents, consequences, and empiric referents are discussed and theories commonly associated with role ambiguity are presented. At the end of the analysis, an operational definition is provided for use in exploring the concept of role ambiguity as it relates to senior nursing students' articulation of the role of the professional nurse. © 2017 Wiley Periodicals, Inc.

Ambiguous science and the visual representation of the real

Science.gov (United States)

Newbold, Curtis Robert

The emergence of visual media as prominent and even expected forms of communication in nearly all disciplines, including those scientific, has raised new questions about how the art and science of communication epistemologically affect the interpretation of scientific phenomena. In this dissertation I explore how the influence of aesthetics in visual representations of science inevitably creates ambiguous meanings. As a means to improve visual literacy in the sciences, I call awareness to the ubiquity of visual ambiguity and its importance and relevance in scientific discourse. To do this, I conduct a literature review that spans interdisciplinary research in communication, science, art, and rhetoric. Furthermore, I create a paradoxically ambiguous taxonomy, which functions to exploit the nuances of visual ambiguities and their role in scientific communication. I then extrapolate the taxonomy of visual ambiguity and from it develop an ambiguous, rhetorical heuristic, the Tetradic Model of Visual Ambiguity. The Tetradic Model is applied to a case example of a scientific image as a demonstration of how scientific communicators may increase their awareness of the epistemological effects of ambiguity in the visual representations of science. I conclude by demonstrating how scientific communicators may make productive use of visual ambiguity, even in communications of objective science, and I argue how doing so strengthens scientific communicators' visual literacy skills and their ability to communicate more ethically and effectively.

Female pseudohermaphroditism in a prenatally diagnosed cloacal malformation with hydronephrosis, dilated bladder, hydrometrocolpos, and oligohydramnios

Directory of Open Access Journals (Sweden)

Chih-Ping Chen

2013-12-01

Conclusion: Prenatal diagnosis of cloacal malformation with ambiguous genitalia should be paid attention to avoid misdiagnosis of a male with an imperforate anus and a perineal fistula. Cytogenetic analysis is helpful to determine the sex under such circumstances.

Clarity and ambiguity in strategic corporate communication

DEFF Research Database (Denmark)

Gulbrandsen, Ib Tunby

2017-01-01

as they are decoupled from the strategy itself. Research limitations/implications – As the findings are based on a study of the understanding and practice of corporate communication strategy in one concrete organization, the study points to the need for additional explorations and examinations of ambiguity in strategic...... how they perceived the writing, reading and enactment of their organization’s new corporate communication strategy. Findings – The analysis reveals the presence of both clarity and ambiguity in the employees’ understanding of the strategy. Both in terms of formulation and implementation. For instance...... corporate communication. Originality/value – Despite numerous studies on the presence of ambiguity in strategy making in the neighbouring field of strategic management, the majority of strategic corporate communication literature largely treats ambiguity as something that should be absent. This has caused...

Clarity and ambiguity in strategic corporate communication

DEFF Research Database (Denmark)

Gulbrandsen, Ib Tunby

2018-01-01

as they are decoupled from the strategy itself. Research limitations/implications – As the findings are based on a study of the understanding and practice of corporate communication strategy in one concrete organization, the study points to the need for additional explorations and examinations of ambiguity in strategic...... how they perceived the writing, reading and enactment of their organization’s new corporate communication strategy. Findings – The analysis reveals the presence of both clarity and ambiguity in the employees’ understanding of the strategy. Both in terms of formulation and implementation. For instance...... corporate communication. Originality/value – Despite numerous studies on the presence of ambiguity in strategy making in the neighbouring field of strategic management, the majority of strategic corporate communication literature largely treats ambiguity as something that should be absent. This has caused...

Risk Management and Insurance Decisions under Ambiguity

DEFF Research Database (Denmark)

Martínez-Correa, Jimmy

I study the impact of ambiguity on insurance decisions and the optimality of insurance contracts. My tractable approach allows me to study the interaction between risk and ambiguity attitudes. When insurance decisions are made independently of other assets, for a given increase in wealth, both risk...... portfolio theory that assumes Subjective Expected Utility theory; however, it provides hints to a possible solution of the under-diversification puzzle of households. I also identify conditions under which more risk or ambiguity aversion decreases the demand for coinsurance. Additionally, I show...... a counterexample to a classical result in insurance economics where an insurance contract with straight deductible is dominated by a coinsurance contract. Finally, I find that a modified Borch rule characterizes the optimal insurance contract with bilateral risk and ambiguity attitudes and heterogeneity in beliefs....

Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model.

Science.gov (United States)

Grau-Moya, Jordi; Ortega, Pedro A; Braun, Daniel A

2016-01-01

A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects' choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects' choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain.

Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model.

Directory of Open Access Journals (Sweden)

Jordi Grau-Moya

Full Text Available A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects' choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects' choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain.

Decision-Making under Ambiguity Is Modulated by Visual Framing, but Not by Motor vs. Non-Motor Context. Experiments and an Information-Theoretic Ambiguity Model

Science.gov (United States)

Grau-Moya, Jordi; Ortega, Pedro A.; Braun, Daniel A.

2016-01-01

A number of recent studies have investigated differences in human choice behavior depending on task framing, especially comparing economic decision-making to choice behavior in equivalent sensorimotor tasks. Here we test whether decision-making under ambiguity exhibits effects of task framing in motor vs. non-motor context. In a first experiment, we designed an experience-based urn task with varying degrees of ambiguity and an equivalent motor task where subjects chose between hitting partially occluded targets. In a second experiment, we controlled for the different stimulus design in the two tasks by introducing an urn task with bar stimuli matching those in the motor task. We found ambiguity attitudes to be mainly influenced by stimulus design. In particular, we found that the same subjects tended to be ambiguity-preferring when choosing between ambiguous bar stimuli, but ambiguity-avoiding when choosing between ambiguous urn sample stimuli. In contrast, subjects’ choice pattern was not affected by changing from a target hitting task to a non-motor context when keeping the stimulus design unchanged. In both tasks subjects’ choice behavior was continuously modulated by the degree of ambiguity. We show that this modulation of behavior can be explained by an information-theoretic model of ambiguity that generalizes Bayes-optimal decision-making by combining Bayesian inference with robust decision-making under model uncertainty. Our results demonstrate the benefits of information-theoretic models of decision-making under varying degrees of ambiguity for a given context, but also demonstrate the sensitivity of ambiguity attitudes across contexts that theoretical models struggle to explain. PMID:27124723

Cytogenetic and molecular study in intersex

African Journals Online (AJOL)

Soheir S. Abou El Ella

2012-07-06

Jul 6, 2012 ... Thirteen cases with ambiguous genitalia were studied, ... among our patients, cases number 2 and 11 were mainly presented as salt losing crisis. Cases 5 and 13 ... goal in any management strategy is to provide a framework.

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXIV. Genus Catageiomyia Theobald

Science.gov (United States)

A comparative, morphological analysis of the female genitalia of species included in genus Catageiomyia Theobald was conducted. Treatment of the genital morphology of the genus includes a composite description of the genus, a detailed description and illustration of the type species (Cg. irritans (...

The Ethics of Strategic Ambiguity: Contrasting Teleologically and Deontologically Based Experiences.

Science.gov (United States)

Paul, Jim; And Others

This paper describes ethical considerations in the use of strategic ambiguity in organizational communication. Ambiguity is defined as "experienced ambiguity" and is distinct from uncertainty and equivocality which are properties of a stimulus. Strategic ambiguity is the use of "calculated ambiguity" in organizations to achieve…

Global optimization applied to GPS positioning by ambiguity functions

International Nuclear Information System (INIS)

Baselga, Sergio

2010-01-01

Differential GPS positioning with carrier-phase observables is commonly done in a process that involves determination of the unknown integer ambiguity values. An alternative approach, named the ambiguity function method, was already proposed in the early days of GPS positioning. By making use of a trigonometric function ambiguity unknowns are eliminated from the functional model before the estimation process. This approach has significant advantages, such as ease of use and insensitivity to cycle slips, but requires such high accuracy in the initial approximate coordinates that its use has been practically dismissed from consideration. In this paper a novel strategy is proposed so that the need for highly accurate initial coordinates disappears: the application of a global optimization method to the ambiguity functions model. The use of this strategy enables the ambiguity function method to compete with the present prevailing approach of ambiguity resolution

Pricing risk and ambiguity: the effect of perspective taking.

Science.gov (United States)

Trautmann, Stefan T; Schmidt, Ulrich

2012-01-01

In the valuation of uncertain prospects, a difference is often observed between selling and buying perspectives. This paper distinguishes between risk (known probabilities) and ambiguity (unknown probabilities) in decisions under uncertainty and shows that the valuation disparity increases under ambiguity compared to risk. It is found that both the comparative versus noncomparative evaluation of risky and ambiguous prospects and the uniqueness of the valuation perspective (either seller or buyer) moderate this increase in the disparity under ambiguity. The finding is consistent with recent theoretical accounts of pricing under uncertainty. We discuss implications for market behaviour and for the ambiguity paradigm as a research tool.

Ambiguity aversion and household portfolio choice puzzles: Empirical evidence*

Science.gov (United States)

Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

2017-01-01

We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks. PMID:28458446

Ambiguity aversion and household portfolio choice puzzles: Empirical evidence.

Science.gov (United States)

Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

2016-03-01

We test the relation between ambiguity aversion and five household portfolio choice puzzles: nonparticipation in equities, low allocations to equity, home-bias, own-company stock ownership, and portfolio under-diversification. In a representative US household survey, we measure ambiguity preferences using custom-designed questions based on Ellsberg urns. As theory predicts, ambiguity aversion is negatively associated with stock market participation, the fraction of financial assets in stocks, and foreign stock ownership, but it is positively related to own-company stock ownership. Conditional on stock ownership, ambiguity aversion is related to portfolio under-diversification, and during the financial crisis, ambiguity-averse respondents were more likely to sell stocks.

Symmetry relations and ambiguities in a free-quark model

International Nuclear Information System (INIS)

Battistel, O.A.; Nemes, M.C.; Battistel, O.L.

1998-01-01

We present a systematic study of one, two and three point functions of vector axial-vector scalar and pseudoscalar densities constructed in a free-quark model in a point of view of a alternative strategy to manipulate and calculate divergent amplitudes. The divergent content of the amplitudes in this technique are left in the form of (external momenta independent) 4-D integrals. Ambiguities and Symmetry Violations in all cases are shown to be associated to terms which involved relations between divergent integrals of the same degree of divergence. We conclude then that it's possible to avoid all these problems. For this purpose a set of conditions must be fulfilled the same ones we need for preserving gauge symmetry in QED. The implications of our studies to others theories and models are also discussed. (author)

Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

DEFF Research Database (Denmark)

Munk, Claus; Rubtsov, Alexey Vladimirovich

2014-01-01

prices. The investor is ambiguous about the inflation model and prefers a portfolio strategy which is robust to model misspecification. Ambiguity about the inflation dynamics is shown to affect the optimal portfolio fundamentally different than ambiguity about the price dynamics of traded assets...

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXVI. Genus Polyleptiomyia Theobald

Science.gov (United States)

A morphological analysis of the female genitalia of species included in genus Polyleptiomyia Theobald was conducted. Treatment of the genital morphology of the genus includes a description of the genus, a detailed description and illustration of the type species, Po. albocephala (Theobald), a list ...

Discrete ambiguities in CP-violating asymmetries in B decays

International Nuclear Information System (INIS)

London, David

1998-01-01

The CP-angles α, β and γ can be extracted from CP-violating asymmetries in the B system, but only up to discrete ambiguities. These discrete ambiguities make it difficult to determine with certainty whether or not new physics is present. I show that, if the condition α+β+γ=π is imposed, there remains a twofold ambiguity in the CP-angle set (α,β,γ), and I discuss ways to cleanly resolve this final discrete ambiguity

An ambiguity in fermionic string perturbation theory

International Nuclear Information System (INIS)

Atick, J.J.; Rabin, J.M.

1988-01-01

Recent investigation by Verlinde and Verlinde has shown that the fermionic string loop amplitudes change by a total derivative term in the moduli space under a change of basis of the supermoduli. This ambiguity is addressed in the context of the heterotic string theory, and shown to be a consequence of an inherent ambiguity in defining integration over the variables of a Grassmann algebra - in this case the Grassmann-valued coordinates of the supermoduli space. A resolution of this ambiguity in genus-two within this formalism is also presented. (orig.)

Characteristics of a pure-state ambiguity function

International Nuclear Information System (INIS)

Praxmeyer, Ludmila; Vitanov, Nikolay; Stenholm, Stig

2009-01-01

We present the necessary and sufficient condition for a square integrable function on R 2N to be an ambiguity function corresponding to a square integrable function on R N . This condition has the form of an integral equation. We also list some easier to check necessary conditions that must be fulfilled by a function that is an ambiguity function of a pure state. We show how to construct a wavefunction corresponding to a given ambiguity function and we present examples of how our formal results can be used in practice.

Attractiveness, diagnostic ambiguity, and disability cues impact perceptions of women with pain.

Science.gov (United States)

LaChapelle, Diane L; Lavoie, Susan; Higgins, Nancy C; Hadjistavropoulos, Thomas

2014-05-01

This experimental study investigated how physical attractiveness, disability cue, and diagnostic ambiguity stereotypes impact perceptions of a patient's pain/disability and personality. After viewing photographs of women pictured with or without a cane, accompanied by descriptions of the women's diagnosis (fibromyalgia or rheumatoid arthritis), 147 university students rated the women's pain/disability and personality. Analyses revealed that more attractive women received lower ratings on pain/disability and higher ratings (more positive) on personality. Moreover, those pictured with a disability cue got higher ratings on both pain/disability and personality, and those with medical evidence of pathology (less ambiguity) got higher ratings on pain/disability and lower ratings on personality. Examination of the 3 stereotypes in a single study enabled an evaluation of their interactions. An Attractiveness × Disability Cue × Diagnostic Ambiguity interaction for ratings of pain/disability revealed that the presence of both medical evidence and a disability cue were needed to override the strong "beautiful is healthy" stereotype. Significant 2-way interactions for ratings of personality indicated that the impact of the disability stereotype tends to be overshadowed by the attractiveness stereotype. The results indicate that these stereotypes have a large effect on perceptions of women with chronic pain and that attractiveness, a contextual variable unrelated to the pain experience, exerts an even stronger effect when there is less objective information available. This could have clinical ramifications for assessment and treatment of patients with chronic pain, which often occurs in the absence of "objective" medical evidence or any external cues of disability. (c) 2014 APA, all rights reserved.

Comparing Tolerance of Ambiguity in Veterinary and Medical Students.

Science.gov (United States)

Hancock, Jason; Hammond, Jennifer A; Roberts, Martin; Mattick, Karen

Current guidelines suggest that educators in both medical and veterinary professions should do more to ensure that students can tolerate ambiguity. Designing curricula to achieve this requires the ability to measure and understand differences in ambiguity tolerance among and within professional groups. Although scales have been developed to measure tolerance of ambiguity in both medical and veterinary professions, no comparative studies have been reported. We compared the tolerance of ambiguity of medical and veterinary students, hypothesizing that veterinary students would have higher tolerance of ambiguity, given the greater patient diversity and less well-established evidence base underpinning practice. We conducted a secondary analysis of questionnaire data from first- to fourth-year medical and veterinary students. Tolerance of ambiguity scores were calculated and compared using the TAMSAD scale (29 items validated for the medical student population), the TAVS scale (27 items validated for the veterinary student population), and a scale comprising the 22 items common to both scales. Using the TAMSAD and TAVS scales, medical students had a significantly higher mean tolerance of ambiguity score than veterinary students (56.1 vs. 54.1, pambiguity than veterinary students, although this depends on the scale used.

X-linked lissencephaly with abnormal genitalia associated with renal phosphate wasting.

Science.gov (United States)

Hahn, A; Gross, C; Uyanik, G; Hehr, U; Hügens-Penzel, M; Alzen, G; Neubauer, B A

2004-06-01

X-linked lissencephaly with abnormal genitalia (XLAG) is a rare disorder caused by mutations in the aristaless-related homeobox (ARX) gene. We report on the clinical data of a boy with a 1-bp deletion (790 delC) resulting in a frame shift in the ARX gene and prolonged survival until age 18 months. Similar to other patients, the boy showed postnatal microcephaly, hypothalamic dysfunction, intractable neonatal seizures, and chronic diarrhoea. In addition, he suffered from exocrine pancreatic insufficiency and renal phosphate wasting became apparent from age 5 months, both of which have not been described previously in XLAG. This allows us to speculate that the phenotype of XLAG is more complex than hitherto known and may include renal phosphate wasting which might not have been observed in other patients due to early death.

Ambiguous Adaptation

DEFF Research Database (Denmark)

Møller Larsen, Marcus; Lyngsie, Jacob

2017-01-01

We investigate the connection between contract duration, relational mechanisms, and premature relationship termination. Based on an analysis of a large sample of exchange relationships in the global service-provider industry, we argue that investments in either longer contract duration or more in...... ambiguous reference points for adaption and thus increase the likelihood of premature termination by restricting the parties' set of adaptive actions....

Crichton ambiguities with infinitely many partial waves

NARCIS (Netherlands)

Atkinson, D.; Kok, L.P.; de Roo, M.

We construct families of spin less two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are

Ambiguity, Ambivalence and Extravagance in The Hunger Games

OpenAIRE

Oliver, Kelly

2014-01-01

I argue that Katniss Everdeen from The Hunger Games is an emblem of what Julia Kristeva calls the “extravagant girl” who wants to have it all and to be the best at everything. Katniss has an ambiguous gender identity, both masculine and feminine, paternal and maternal. And she has ambivalent desires. I conclude that this ambiguity and ambivalence open up new possibilities for girls and initiate an aesthetics of ambiguity.

Children do not exhibit ambiguity aversion despite intact familiarity bias.

Science.gov (United States)

Li, Rosa; Brannon, Elizabeth M; Huettel, Scott A

2014-01-01

The phenomenon of ambiguity aversion, in which risky gambles with known probabilities are preferred over ambiguous gambles with unknown probabilities, has been thoroughly documented in adults but never measured in children. Here, we use two distinct tasks to investigate ambiguity preferences of children (8- to 9-year-olds) and a comparison group of adults (19- to 27-year-olds). Across three separate measures, we found evidence for significant ambiguity aversion in adults but not in children and for greater ambiguity aversion in adults compared to children. As ambiguity aversion in adults has been theorized to result from a preference to bet on the known and avoid the unfamiliar, we separately measured familiarity bias and found that children, like adults, are biased towards the familiar. Our findings indicate that ambiguity aversion emerges across the course of development between childhood and adolescence, while a familiarity bias is already present in childhood.

Azimuth Phase Coding for Range Ambiguity Suppression in SAR

DEFF Research Database (Denmark)

Dall, Jørgen; Kusk, Anders

2004-01-01

A novel ambiguity suppression technique is proposed. Range ambiguities in synthetic aperture radar (SAR) images are eliminated with an azimuth filter after having applied an azimuth phase modulation to the transmitted pulses and a corresponding demodulation to the received pulses. The technique...... excels by actually eliminating the ambiguities rather than just defocusing them as most other techniques do. This makes the proposed technique applicable to distributed targets. The range ambiguity suppression permits the pulse repetition frequency (PRF) to exceed the upper limit otherwise defined...... by the antenna elevation dimension. The fundamental antenna area constraint still applies, but the PRF can be chosen with more freedom. In addition to ambiguity suppression, potential applications include nadir return elimination and signal-to-noise ratio improvement....

Constraints and Ambiguity

DEFF Research Database (Denmark)

Dove, Graham; Biskjær, Michael Mose; Lundqvist, Caroline Emilie

2017-01-01

groups of students building three models each. We studied groups building with traditional plastic bricks and also using a digital environment. The building tasks students undertake, and our subsequent analysis, are informed by the role constraints and ambiguity play in creative processes. Based...

Does ambiguity aversion influence the framing effect during decision making?

Science.gov (United States)

Osmont, Anaïs; Cassotti, Mathieu; Agogué, Marine; Houdé, Olivier; Moutier, Sylvain

2015-04-01

Decision-makers present a systematic tendency to avoid ambiguous options for which the level of risk is unknown. This ambiguity aversion is one of the most striking decision-making biases. Given that human choices strongly depend on the options' presentation, the purpose of the present study was to examine whether ambiguity aversion influences the framing effect during decision making. We designed a new financial decision-making task involving the manipulation of both frame and uncertainty levels. Thirty-seven participants had to choose between a sure option and a gamble depicting either clear or ambiguous probabilities. The results revealed a clear preference for the sure option in the ambiguity condition regardless of frame. However, participants presented a framing effect in both the risk and ambiguity conditions. Indeed, the framing effect was bidirectional in the risk condition and unidirectional in the ambiguity condition given that it did not involve preference reversal but only a more extreme choice tendency.

Measuring Ambiguity in HLA Typing Methods

Science.gov (United States)

Madbouly, Abeer; Freeman, John; Maiers, Martin

2012-01-01

In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched), but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure objectively evaluates HLA

Measuring ambiguity in HLA typing methods.

Directory of Open Access Journals (Sweden)

Vanja Paunić

Full Text Available In hematopoietic stem cell transplantation, donor selection is based primarily on matching donor and patient HLA genes. These genes are highly polymorphic and their typing can result in exact allele assignment at each gene (the resolution at which patients and donors are matched, but it can also result in a set of ambiguous assignments, depending on the typing methodology used. To facilitate rapid identification of matched donors, registries employ statistical algorithms to infer HLA alleles from ambiguous genotypes. Linkage disequilibrium information encapsulated in haplotype frequencies is used to facilitate prediction of the most likely haplotype assignment. An HLA typing with less ambiguity produces fewer high-probability haplotypes and a more reliable prediction. We estimated ambiguity for several HLA typing methods across four continental populations using an information theory-based measure, Shannon's entropy. We used allele and haplotype frequencies to calculate entropy for different sets of 1,000 subjects with simulated HLA typing. Using allele frequencies we calculated an average entropy in Caucasians of 1.65 for serology, 1.06 for allele family level, 0.49 for a 2002-era SSO kit, and 0.076 for single-pass SBT. When using haplotype frequencies in entropy calculations, we found average entropies of 0.72 for serology, 0.73 for allele family level, 0.05 for SSO, and 0.002 for single-pass SBT. Application of haplotype frequencies further reduces HLA typing ambiguity. We also estimated expected confirmatory typing mismatch rates for simulated subjects. In a hypothetical registry with all donors typed using the same method, the entropy values based on haplotype frequencies correspond to confirmatory typing mismatch rates of 1.31% for SSO versus only 0.08% for SBT. Intermediate-resolution single-pass SBT contains the least ambiguity of the methods we evaluated and therefore the most certainty in allele prediction. The presented measure

Triple-frequency GPS precise point positioning with rapid ambiguity resolution

Science.gov (United States)

Geng, Jianghui; Bock, Yehuda

2013-05-01

At present, reliable ambiguity resolution in real-time GPS precise point positioning (PPP) can only be achieved after an initial observation period of a few tens of minutes. In this study, we propose a method where the incoming triple-frequency GPS signals are exploited to enable rapid convergences to ambiguity-fixed solutions in real-time PPP. Specifically, extra-wide-lane ambiguity resolution can be first achieved almost instantaneously with the Melbourne-Wübbena combination observable on L2 and L5. Then the resultant unambiguous extra-wide-lane carrier-phase is combined with the wide-lane carrier-phase on L1 and L2 to form an ionosphere-free observable with a wavelength of about 3.4 m. Although the noise of this observable is around 100 times the raw carrier-phase noise, its wide-lane ambiguity can still be resolved very efficiently, and the resultant ambiguity-fixed observable can assist much better than pseudorange in speeding up succeeding narrow-lane ambiguity resolution. To validate this method, we use an advanced hardware simulator to generate triple-frequency signals and a high-grade receiver to collect 1-Hz data. When the carrier-phase precisions on L1, L2 and L5 are as poor as 1.5, 6.3 and 1.5 mm, respectively, wide-lane ambiguity resolution can still reach a correctness rate of over 99 % within 20 s. As a result, the correctness rate of narrow-lane ambiguity resolution achieves 99 % within 65 s, in contrast to only 64 % within 150 s in dual-frequency PPP. In addition, we also simulate a multipath-contaminated data set and introduce new ambiguities for all satellites every 120 s. We find that when multipath effects are strong, ambiguity-fixed solutions are achieved at 78 % of all epochs in triple-frequency PPP whilst almost no ambiguities are resolved in dual-frequency PPP. Therefore, we demonstrate that triple-frequency PPP has the potential to achieve ambiguity-fixed solutions within a few minutes, or even shorter if raw carrier-phase precisions are

Isoclinic Ambiguity Unwrapping of Circular Ring under Diametric Compression

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Huang M.-J.

2010-06-01

Full Text Available Isoclinic and isochromatic parameters in photoelastic analysis are formulated by arc tangent function of several phase shifting frames but for isochromatic calculation it is, in addition, in terms of isoclinic data also. Thus, any isoclinic phase ambiguity would also result in the phase inconsistencies of isochromatic calculation and cause unwrapping problems and difficulties. Many methods had been proposed to treat these kinds of isochromatic fringes but lots of treatments were needed for the correct retrieval. In this work, the isoclinic ambiguity problem is investigated and solved directly by a novel regional phase unwrapping technique. Once the isoclinic phase ambiguity problems are solved, a correct isoclinic result can be obtained. Then, substituting this result into the isochromatic formation yields an ambiguity free isochromatic phase map, which can be easily restored by any phase unwrapping algorithm. A stress frozen sample - circular ring under diametric compression verifies its effectiveness. Usually happened is that this kind of sample is with ambiguous isoclinic data which would cause phase ambiguities of the isochromatic formulation if not treated well first.

Estimating ambiguity preferences and perceptions in multiple prior models: Evidence from the field.

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Dimmock, Stephen G; Kouwenberg, Roy; Mitchell, Olivia S; Peijnenburg, Kim

2015-12-01

We develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of moderate to high likelihood involving gains, but ambiguity seeking prevails for low likelihoods and for losses. We show that choices made under ambiguity in the gain domain are best explained by the α-MaxMin model, with one parameter measuring ambiguity aversion (ambiguity preferences) and a second parameter quantifying the perceived degree of ambiguity (perceptions about ambiguity). The ambiguity aversion parameter α is constant and prior probability sets are asymmetric for low and high likelihood events. The data reject several other models, such as MaxMin and MaxMax, as well as symmetric probability intervals. Ambiguity aversion and the perceived degree of ambiguity are both higher for men and for the college-educated. Ambiguity aversion (but not perceived ambiguity) is also positively related to risk aversion. In the loss domain, we find evidence of reflection, implying that ambiguity aversion for gains tends to reverse into ambiguity seeking for losses. Our model's estimates for preferences and perceptions about ambiguity can be used to analyze the economic and financial implications of such preferences.

Estimating ambiguity preferences and perceptions in multiple prior models: Evidence from the field

Science.gov (United States)

Dimmock, Stephen G.; Kouwenberg, Roy; Mitchell, Olivia S.; Peijnenburg, Kim

2016-01-01

We develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of moderate to high likelihood involving gains, but ambiguity seeking prevails for low likelihoods and for losses. We show that choices made under ambiguity in the gain domain are best explained by the α-MaxMin model, with one parameter measuring ambiguity aversion (ambiguity preferences) and a second parameter quantifying the perceived degree of ambiguity (perceptions about ambiguity). The ambiguity aversion parameter α is constant and prior probability sets are asymmetric for low and high likelihood events. The data reject several other models, such as MaxMin and MaxMax, as well as symmetric probability intervals. Ambiguity aversion and the perceived degree of ambiguity are both higher for men and for the college-educated. Ambiguity aversion (but not perceived ambiguity) is also positively related to risk aversion. In the loss domain, we find evidence of reflection, implying that ambiguity aversion for gains tends to reverse into ambiguity seeking for losses. Our model’s estimates for preferences and perceptions about ambiguity can be used to analyze the economic and financial implications of such preferences. PMID:26924890

The dark side of ambiguous discrimination: how state self-esteem moderates emotional and behavioural responses to ambiguous and unambiguous discrimination.

Science.gov (United States)

Cihangir, Sezgin; Barreto, Manuela; Ellemers, Naomi

2010-03-01

Two experiments examine how experimentally induced differences in state self-esteem moderate emotional and behavioural responses to ambiguous and unambiguous discrimination. Study 1 (N=108) showed that participants who were exposed to ambiguous discrimination report more negative self-directed emotions when they have low compared to high self-esteem. These differences did not emerge when participants were exposed to unambiguous discrimination. Study 2 (N=118) additionally revealed that self-esteem moderated the effect of ambiguous discrimination on self-concern, task performance, and self-stereotyping. Results show that ambiguous discrimination caused participants with low self-esteem to report more negative self-directed emotions, more self-concern, an inferior task performance, and more self-stereotyping, compared to participants in the high self-esteem condition. Emotional and behavioural responses to unambiguous discrimination did not depend on the induced level of self-esteem in these studies.

Crichton ambiguities with infinitely many partial waves

International Nuclear Information System (INIS)

Atkinson, D.; Kok, L.P.; de Roo, M.

1978-01-01

We construct families of spinless two-particle unitary cross sections that possess a nontrivial discrete phase-shift ambiguity, with in general an infinite number of nonvanishing partial waves. A numerical investigation reveals that some of the previously known finite Crichton ambiguities are merely special cases of the newly constructed examples

Coding of level of ambiguity within neural systems mediating choice.

Science.gov (United States)

Lopez-Paniagua, Dan; Seger, Carol A

2013-01-01

Data from previous neuroimaging studies exploring neural activity associated with uncertainty suggest varying levels of activation associated with changing degrees of uncertainty in neural regions that mediate choice behavior. The present study used a novel task that parametrically controlled the amount of information hidden from the subject; levels of uncertainty ranged from full ambiguity (no information about probability of winning) through multiple levels of partial ambiguity, to a condition of risk only (zero ambiguity with full knowledge of the probability of winning). A parametric analysis compared a linear model in which weighting increased as a function of level of ambiguity, and an inverted-U quadratic models in which partial ambiguity conditions were weighted most heavily. Overall we found that risk and all levels of ambiguity recruited a common "fronto-parietal-striatal" network including regions within the dorsolateral prefrontal cortex, intraparietal sulcus, and dorsal striatum. Activation was greatest across these regions and additional anterior and superior prefrontal regions for the quadratic function which most heavily weighs trials with partial ambiguity. These results suggest that the neural regions involved in decision processes do not merely track the absolute degree ambiguity or type of uncertainty (risk vs. ambiguity). Instead, recruitment of prefrontal regions may result from greater degree of difficulty in conditions of partial ambiguity: when information regarding reward probabilities important for decision making is hidden or not easily obtained the subject must engage in a search for tractable information. Additionally, this study identified regions of activity related to the valuation of potential gains associated with stimuli or options (including the orbitofrontal and medial prefrontal cortices and dorsal striatum) and related to winning (including orbitofrontal cortex and ventral striatum).

Al-Awadi/Raas-Rothschild/Schinzel (AARRS) phocomelia syndrome: case report and developmental field analysis.

Science.gov (United States)

Subhani, Muhammad; Akangire, Gangaram; Kulkarni, Archana; Wilson, Golder N

2009-07-01

We describe a girl infant with anomalies of the left pelvis and lower limb (pelvic, femoral, and tibial hypogenesis with absent fibula), subtle facial changes, patent foraman ovale, single umbilical artery, single kidney, and imperforate anus. The external genitalia were asymmetric and ambiguous with normal uterus and ovaries visualized by ultrasound. The anomalies are compatible with previously reported cases of Al-Awadi/Raas-Rothschild/Schinzel (AARRS) phocomelia, an autosomal recessive disorder with WNT7 gene mutations documented in one family. We suggest that AARRS phocomelia, Fuhrmann syndrome, and similar conditions comprise a spectrum, and that the anomaly pattern derives from serial action of the same signal pathways within primary (e.g., the major axes), secondary (e.g., heart or limb primordia), and/or local (e.g., tibial-fibular differentiation) developmental fields.

Pyovagina and stump pyometra in a neutered XX sex-reversed Beagle: a case report

International Nuclear Information System (INIS)

Williams, J.; Partington, B.P.; Smith, B.; Hedlund, C.S.; Law, J.M.

1997-01-01

An 18-month-old, neutered male beagle presented with acute abdominal signs and a suppurative infection of the urogenital tract. Chromosomal sex was female (78, XX), gonadal sex was male (testicles), and phenotypic sex was ambiguous, with evidence of both male and female duct systems. The internal and external genitalia consisted of epididymides, an underdeveloped uterus with an immature spermatic cord, communication between the uterus or cranial vagina and the membranous urethra, a urethrographically male urethra, a hypoplastic os penis, and a hypoplastic penis with hypospadia. Based on these findings and the familial history of a similarly affected litter mate, the dog was diagnosed as having the XX male syndrome with pyovagina and uterine stump pyometra. Radiographic and ultrasonographic investigations are described, and abnormalities of chromosomal sex, gonadal sex, and phenotypic sex are discussed

Ambiguities in the reaction mechanism for (e,e'N)

International Nuclear Information System (INIS)

Forest, T. de Jr.

1984-01-01

The primary motivation for performing quasi-elastic (e,e'N) experiments revolves around the plane wave impulse approximation (PWIA) description of this reaction. Since the PWIA is an approximation, corrections are necessary in practice in order to extract the desired nuclear structure. Unless one understands the physics behind these corrections this introduces ambiguities. In fact the PWIA itself is an ambiguous prescription since a 'free' off-shell cross section is not a well-defined concept. It is these ambiguities which are discussed in this talk. Most of the paper is devoted to the ambiguities associated with the electromagnetic interaction. The author concentrates on four topics: (1) the interaction of the electron with the nucleus in general; (2) ambiguities in the application of the impulse approximation; (3) the sigma-omega model; and (4) the Coulomb sum rule. (Auth.)

Wing pattern morphology of three closely related Melitaea (Lepidoptera, Nymphalidae species reveals highly inaccurate external morphology-based species identification

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Jure Jugovic

2014-06-01

Full Text Available Wing morphology of the three closely related species of Melitaea – M. athalia (Rottemburg, 1775, M. aurelia (Nickerl, 1850 and M. britomartis Assmann, 1847 – co-occurring in the Balkans (SE Europe was investigated in detail through visual inspection, morphometric analysis and multivariate statistical analysis. Results are compared to recent phylogenetic studies, searching for concordant patterns and discrepancies between the two approaches. The morphology of the genitalic structures is also compared with the results of the other two approaches. The main conclusions are as follows: (1 small albeit significant differences in wing morphology exist among the three species and (2 while the structure of male genitalia and phylogenetic position of the three species are concordant, they are (3 in discordance with the wing morphology. The present study represents another example where identification based on external morphology would lead to highly unreliable determinations, hence identification based on phylogenetic studies and/or genitalia is strongly recommended not only for the three studied species but also more broadly within the genus. Furthermore, we show that some of the characters generally used in the identification of these three Melitaea species should be avoided in future.

Gauge ambiguities in (rvec e,e'rvec N) reactions

International Nuclear Information System (INIS)

Kelly, J.J.

1997-01-01

We examine the sensitivity of the distorted-wave impulse approximation for single-nucleon electromagnetic knockout from valence orbitals to ambiguities in the one-body current operator. Violations of current conservation are classified as gauge ambiguities, whereas the elements of a particular class of structural differences off shell are labeled Gordon ambiguities. Gauge ambiguities in differential cross sections and longitudinal response functions are found to increase with missing momentum and to become particularly severe for low-Q 2 kinematical conditions that are far from quasifree but are sometimes used to investigate correlations. The azimuthal asymmetry may provide a useful experimental means for selecting a gauge. Gordon ambiguities increase with Q 2 and are larger for relativistic than for nonrelativistic approaches. Because ambiguities in the one-body current are at least as large as effects due to correlations and there are additional uncertainties due to two-body currents, final-state interactions, and relativistic distortion, we conclude that is unlikely that information about correlations can be extracted from single-nucleon knockout from valence orbitals at large missing momentum. On the other hand, gauge and Gordon ambiguities and uncertainties in final-state interactions have very little effect upon the helicity-dependent recoil polarization, which can be used to investigate the roles of two-body currents and/or possible medium modifications of the one-body current. copyright 1997 The American Physical Society

There is a continuum ambiguity for elastic πN amplitudes

International Nuclear Information System (INIS)

Atkinson, D.; Roo, M. de; Polman, T.J.T.M.

1984-01-01

The implicit-function method of constructing phase-factor continuum ambiguities in phase-shift analysis is briefly reviewed, and new numerical examples are given of ambiguities in πN phase shifts at 1997 MeV. Since the ambiguous amplitudes differ by more than 5%, while the corresponding cross sections and polarizations are equal, to better than a computational accuracy of 0.007%, numerical credence is given to the theoretical claim that the continuum ambiguity exists. (orig.)

External Genital Development, Urethra Formation, and Hypospadias Induction in Guinea Pig: A Double Zipper Model for Human Urethral Development.

Science.gov (United States)

Wang, Shanshan; Shi, Mingxin; Zhu, Dongqing; Mathews, Ranjiv; Zheng, Zhengui

2018-03-01

To determine whether the guinea pig phallus would be an appropriate model of human penile development, we characterized the embryology and sexual differentiation of guinea pig external genitalia and attended to induce hypospadias in males and tubular urethra formation in females pharmacologically. The external genitalia of guinea pig were collected from genital swelling initiation to newborn stages, and scanning electronic microscopy and histology were performed to visualize the morphology and structure. Immunohistochemistry was used to determine the androgen receptor localization. Bicalutamide and methyltestosterone were given to pregnant dams to reveal the role and timing of androgen in guinea pig penile masculinization. Canalization and dorsal-to-ventral movement of the urethral canal develops the urethral groove in both sexes, and then the males perform distal-opening-proximal-closing to form tubular urethra. More nuclear-localized androgen receptor is found in proximal genital tubercles of males than in females at (E) 29. Antiandrogen treatment at E26-E30 can cause hypospadias, and methyltestosterone administration at E27-E31 can induce tubular urethra formation in females. Fetal development of the guinea pig phallus is homologous to that of humans. Although guinea pig has structures similar to mouse, the urethral groove and the tubular urethra formation are more similar to humans. Antiandrogen treatment causes hypospadias in males and additional androgen induces tubular urethra formation in females. Thus, guinea pig is an appropriate model for further study of cellular and molecular mechanisms involved in distal-opening-proximal-closing in tubular urethra formation and the evaluation of the pathophysiological processes of hypospadias. Published by Elsevier Inc.

The Communicative Function of Ambiguity in Language

Science.gov (United States)

Piantadosi, Steven T.; Tily, Harry; Gibson, Edward

2012-01-01

We present a general information-theoretic argument that all efficient communication systems will be ambiguous, assuming that context is informative about meaning. We also argue that ambiguity allows for greater ease of processing by permitting efficient linguistic units to be re-used. We test predictions of this theory in English, German, and…

Localizing Expression of Ambiguity

National Research Council Canada - National Science Library

Bear, John; Hobbs, Sr, Jerry R

1987-01-01

In this paper we describe an implemented program for localizing the expression of many types of syntactic ambiguity, in the logical forms of sentences, in a manner convenient for subsequent inferential processing...

Characterizing Early Psychosocial Functioning of Parents of Children with Moderate to Severe Genital Ambiguity due to Disorders of Sex Development.

Science.gov (United States)

Suorsa, Kristina I; Mullins, Alexandria J; Tackett, Alayna P; Reyes, Kristy J Scott; Austin, Paul; Baskin, Laurence; Bernabé, Kerlly; Cheng, Earl; Fried, Allyson; Frimberger, Dominic; Galan, Denise; Gonzalez, Lynette; Greenfield, Saul; Kropp, Bradley; Meyer, Sabrina; Meyer, Theresa; Nokoff, Natalie; Palmer, Blake; Poppas, Dix; Paradis, Alethea; Yerkes, Elizabeth; Wisniewski, Amy B; Mullins, Larry L

2015-12-01

We examined the psychosocial characteristics of parents of children with disorders of sex development at early presentation to a disorders of sex development clinic. Parental anxiety, depression, quality of life, illness uncertainty and posttraumatic stress symptoms were assessed. Additionally we evaluated the relationship of assigned child gender to parental outcomes. A total of 51 parents of children with ambiguous or atypical genitalia were recruited from 7 centers specializing in treatment of disorders of sex development. At initial assessment no child had undergone genitoplasty. Parents completed the Cosmetic Appearance Rating Scale, Beck Anxiety Inventory, Beck Depression Inventory, SF-36, Parent Perception of Uncertainty Scale and Impact of Event Scale-Revised. A large percentage of parents (54.5%) were dissatisfied with the genital appearance of their child, and a small but significant percentage reported symptoms of anxiety, depression, diminished quality of life, uncertainty and posttraumatic stress. Few gender differences emerged. Although many parents function well, a subset experience significant psychological distress around the time of diagnosis of a disorder of sex development in their child. Early screening to assess the need for psychosocial interventions is warranted. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Intolerance for approach of ambiguity in social anxiety disorder.

Science.gov (United States)

Kuckertz, Jennie M; Strege, Marlene V; Amir, Nader

2017-06-01

Previous research has utilised the approach-avoidance task (AAT) to measure approach and avoidance action tendencies in socially anxious individuals. "Neutral" social stimuli may be perceived as ambiguous and hence threatening to socially anxious individuals, however it is unclear whether this results in difficulty approaching ambiguous ("neutral") versus unambiguous threat (e.g. disgust) faces (i.e. intolerance of ambiguity). Thirty participants with social anxiety disorder (SADs) and 29 non-anxious controls completed an implicit AAT in which they were instructed to approach or avoid neutral and disgust faces (i.e. pull or push a joystick) based on colour of the picture border. Results indicated that SADs demonstrated greater difficulty approaching neutral relative to disgust faces. Moreover, intolerance for approach of ambiguity predicted social anxiety severity while controlling for the effects of trait anxiety and depression. Our results provide further support for the role of intolerance of ambiguity in SAD.

Absence of the Gribov ambiguity in a quadratic gauge

International Nuclear Information System (INIS)

Raval, Haresh

2016-01-01

The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S 3 , when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

Absence of the Gribov ambiguity in a quadratic gauge

Energy Technology Data Exchange (ETDEWEB)

Raval, Haresh [Indian Institute of Technology, Bombay, Department of Physics, Mumbai (India)

2016-05-15

The Gribov ambiguity exists in various gauges. Algebraic gauges are likely to be ambiguity free. However, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. In addition, they are not generally compatible with the boundary conditions on the gauge fields, which are needed to compactify the space i.e., the ambiguity continues to exist on a compact manifold. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We consider an example of a spherically symmetric gauge field configuration in which we prove that this Lorentz invariant gauge removes the ambiguity on a compact manifold S{sup 3}, when a proper boundary condition on the gauge configuration is taken into account. Thus, we provide one example where the ambiguity is absent on a compact manifold in the algebraic gauge. We also show that the BRST invariance is preserved in this gauge. (orig.)

Dealing With Uncertainty: Testing Risk- and Ambiguity-Attitude Across Adolescence.

Science.gov (United States)

Blankenstein, Neeltje E; Crone, Eveline A; van den Bos, Wouter; van Duijvenvoorde, Anna C K

2016-01-01

Attitudes to risk (known probabilities) and attitudes to ambiguity (unknown probabilities) are separate constructs that influence decision making, but their development across adolescence remains elusive. We administered a choice task to a wide adolescent age-range (N = 157, 10-25 years) to disentangle risk- and ambiguity-attitudes using a model-based approach. Additionally, this task was played in a social context, presenting choices from a high risk-taking peer. We observed age-related changes in ambiguity-attitude, but not risk-attitude. Also, ambiguity-aversion was negatively related to real-life risk taking. Finally, the social context influenced only risk-attitudes. These results highlight the importance of disentangling risk- and ambiguity-attitudes in adolescent risk taking.

RELATION OF COACHING BEHAVIOR AND ROLE AMBIGUITY

Directory of Open Access Journals (Sweden)

Karamousalidis G.

2010-08-01

Full Text Available The purpose of this research was to investigate the relationship between coaching behavior and role ambiguity in defensive responsibilities using interdependent Greek sport teams. Athlete perceptions of role ambiguity (defense were assessed using a questionnaire developed by Beauchamp, Bray, Eys and Carron (2002 andcoaching behavior was assessed using the Coaching Behavior Questionnaire, (Williams, et. al., 2003. The sample consisted of 409 athletes of basketball, volleyball, handball and soccer. Confirmatory factor analysis provided the construct validity of the questionnaires and correlations among the scales confirmed construct validity. The implications of the results are discussed and future research should continue to investigate the multidimensional models of both coaching behavior and role ambiguity in sport settings.

Quantization ambiguity and the Aharanov-Bohm effect

International Nuclear Information System (INIS)

Kunstatter, G.

1983-01-01

A brief review is given of the role of quantization ambiguity in both quantum mechanics and quantum field theory. The author points out that quantization ambiguity is not relevant to discussions of physical experiments designed to test the Aharanov-Bohm effect. A recent proposal for such an experiment involving Aharanov-Bohm currents in thin superconducting cylinders is mentioned. (Auth.)

Genotype × environment interaction is weaker in genitalia than in mating signals and body traits in Enchenopa treehoppers (Hemiptera: Membracidae).

Science.gov (United States)

Rodríguez, Rafael L; Al-Wathiqui, Nooria

2011-07-01

Theory predicts that selection acting across environments should erode genetic variation in reaction norms; i.e., selection should weaken genotype × environment interaction (G × E). In spite of this expectation, G × E is often detected in fitness-related traits. It thus appears that G × E is at least sometimes sustained under selection, a possibility that highlights the need for theory that can account for variation in the presence and strength of G × E. We tested the hypothesis that trait differences in developmental architecture contribute to variation in the expression of G × E. Specifically, we assessed the influence of canalization (robustness to genetic or environmental perturbations) and condition-dependence (association between trait expression and prior resource acquisition or vital cellular processes). We compared G × E across three trait types expected to differ in canalization and condition-dependence: mating signals, body size-related traits, and genitalia. Because genitalia are expected to show the least condition-dependence and the most canalization, they should express weaker G × E than the other trait types. Our study species was a member of the Enchenopa binotata species complex of treehoppers. We found significant G × E in most traits; G × E was strongest in signals and body traits, and weakest in genitalia. These results support the hypothesis that trait differences in developmental architecture (canalization and condition-dependence) contribute to variation in the expression of G × E. We discuss implications for the dynamics of sexual selection on different trait types.

Ambiguous genitalia in a fertile, unilaterally cryptorchid male miniature schnauzer dog.

Science.gov (United States)

Breshears, M A; Peters, J L

2011-09-01

A 7-year-old male miniature schnauzer dog with unilateral cryptorchidism was presented for elective orchiectomy. Surgery to remove the cryptorchid testis revealed a fully formed uterus with horns attached to both testis and the body and cervix terminating at the prostate gland. The gross and microscopic diagnosis for the genital tract was persistent Müllerian duct syndrome with unilateral cryptorchidism. Additional associated lesions included cystic endometrial hyperplasia and a solitary, intratubular seminoma within the undescended testis. Persistent Müllerian duct syndrome is rare among domestic animals but is more common in miniature schnauzer dogs because of inheritance as an autosomal recessive trait.

Performance management and goal ambiguity: managerial implications in a single payer system.

Science.gov (United States)

Calciolari, Stefano; Cantù, Elena; Fattore, Giovanni

2011-01-01

Goal ambiguity influences the effectiveness of performance management systems to drive organizations toward enhanced results. The literature analyzes the antecedents of goal ambiguity and shows the influence of goal ambiguity on the performance of U.S. federal agencies. However, no study has analyzed goal ambiguity in other countries or in health care systems. This study has three aims: to test the validity of a measurement instrument for goal ambiguity, to investigate its main antecedents, and to explore the relationship between goal ambiguity and organizational performance in a large, public, Beveridge-type health care system. A nationwide survey of general managers of the Italian national health system was performed. A factor analysis was used to validate the mono-dimensionality of an instrument that measured goal ambiguity. Structural equation modeling was used to test both the antecedents and the influence of goal ambiguity on organizational performance. Data from 135 health care organizations (53% response rate) were available for analysis. The results confirm the mono-dimensionality of the instrument, the existence of two environmental sources of ambiguity (political endorsement and governance commitment), and the negative relationship between goal ambiguity and organizational performance. Goal ambiguity matters because it may hamper organizational performance. Therefore, performance should be fostered by reducing goal ambiguity (e.g., goal-setting model, funding arrangements, and political support). Mutatis mutandis, our results may apply to public health care systems of other countries or other "public interest" sectors, such as social care and education.

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXVIII. Genus Petermattinglyius Reinert, Harbach and Kitching.

Science.gov (United States)

A comparative, morphological analysis of the female genitalia of species of the genus Petermattinglyius Reinert, Harbach and Kitching was conducted and a composite description is provided. Petermattinglyius is divided into two subgenera, Petermattinglyius and Aglaonotus Reinert, Harbach and Kitchin...

Inevitable ambiguity in perturbation around flat space-time

International Nuclear Information System (INIS)

Ichinose, S.; Kaminaga, Y.

1989-01-01

Perturbation of general-relativistic predictions around flat geometry, in general, introduces inevitable ambiguity. The ambiguity reflects the geometrical nature of general relativity and is never a difficulty of it. We explain it by taking a concrete example of the radar-echo experiment

Hierarchical Morphological Structure and Ambiguity

DEFF Research Database (Denmark)

Vikner, Carl; Vikner, Sten

2008-01-01

English has a number of adjectives of the type unXable, adjectives that contain the prefix un- and the adjectivising suffix -able, e.g. unlockable or undoable. Many of these adjectives are ambiguous. If a door is unlockable, it may either mean that it cannot be locked (it is not lockable), as exp......English has a number of adjectives of the type unXable, adjectives that contain the prefix un- and the adjectivising suffix -able, e.g. unlockable or undoable. Many of these adjectives are ambiguous. If a door is unlockable, it may either mean that it cannot be locked (it is not lockable...

Removing Ambiguities of IP Telephony Traffic Using Protocol Scrubbers

Directory of Open Access Journals (Sweden)

Bazara I. A. Barry

2012-10-01

Full Text Available Network intrusion detection systems (NIDSs face the serious challenge of attacks such as insertion and evasion attacks that are caused by ambiguous network traffic. Such ambiguity comes as a result of the nature of network traffic which includes protocol implementation variations and errors alongside legitimate network traffic. Moreover, attackers can intentionally introduce further ambiguities in the traffic. Consequently, NIDSs need to be aware of these ambiguities when detection is performed and make sure to differentiate between true attacks and protocol implementation variations or errors; otherwise, detection accuracy can be affected negatively. In this paper we present the design and implementation of tools that are called protocol scrubbers whose main functionality is to remove ambiguities from network traffic before it is presented to the NIDS. The proposed protocol scrubbers are designed for session initiation and data transfer protocols in IP telephony systems. They guarantee that the traffic presented to NIDSs is unambiguous by eliminating ambiguous behaviors of protocols using well-designed protocol state machines, and walking through packet headers of protocols to make sure packets will be interpreted in the desired way by the NIDS. The experimental results shown in this paper demonstrate the good quality and applicability of the introduced scrubbers.

Perfil clínico de 62 casos de distúrbios da diferenciação sexual Clinical profile of 62 cases of sexual differentiation disorders

Directory of Open Access Journals (Sweden)

Juliana Gabriel R. de Andrade

2008-12-01

Full Text Available OBJETIVO: Descrever o perfil clínico dos casos de distúrbios da diferenciação sexual em acompanhamento no Instituto Estadual de Diabetes e Endocrinologia Luiz Capriglione, no Rio de Janeiro, nos últimos cinco anos. MÉTODOS: Revisão dos prontuários dos pacientes, com o diagnóstico de genitália ambígua em acompanhamento nos últimos cinco anos, segundo os critérios clínicos descritos por Danish, em 1982. O registro mais antigo foi feito em 1981 e o mais recente de junho de 2006. RESULTADOS: Foram encontrados 62 casos de genitália ambígua: 26 com registro do sexo feminino e 36 com registro do sexo masculino. O diagnóstico mais freqüente foi o de hiperplasia congênita de supra-renal (33,9%, seguido de quadros sindrômicos (14,5% e disgenesias gonadais (9,7%. A média de idade ao diagnóstico foi de 7,2 anos (de zero a 42 anos. CONCLUSÕES: A ambigüidade genital não é uma doença específica, mas um conjunto de alterações que direcionam o clínico a buscar diagnósticos específicos. A freqüência dessa afecção depende dos critérios diagnósticos utilizados. A adoção de critérios amplos aumenta a chance de detecção precoce do quadro bem como de cuidado adequado a crianças com distúrbios da diferenciação sexual.OBJECTIVE: To report patients with ambiguous genitalia assisted at the State Institute of Diabetes and Endocrinology of Rio de Janeiro, Brazil, in the last five years. METHODS: Retrospective chart review of all cases of ambiguous genitalia, classified according to Danish criteria (1982, who attended follow-up visits in the last five years. The oldest record is from 1981 and the most recent one, 2006. RESULTS: 62 patients with ambiguous genitalia were found: 26 of them assigned as females and 36 as males. The most frequent diagnosis was congenital adrenal hyperplasia (33.9%, followed by syndromic diseases (14.5% and gonadal dysgenesis (9.7%. The majority of patients with ambiguous genitalia were detected at

PENGARUH ROLE AMBIGUITY DAN ROLE CONFLICT TERHADAP KOMITMEN INDEPENDENSI AUDITOR INTERNAL

Directory of Open Access Journals (Sweden)

Angga Prasetyo

2011-05-01

Full Text Available This study aims to determine the influence of role conflict (role conflict against the commitmentof internal auditors’ independence, and know the effect of role ambiguity (role ambiguity ofthe Internal Auditor independence commitment. Data was collected through primary method byusing a questionnaire. Then performed the data analysis that includes classical assumption test,F test, t test, and analysis of coefficient of determination (R2. To analyze using SPSS softwareversion 16. Based on research result shows that role conflict has a significant negative effect oncommitment to the independence of internal auditors, and role ambiguity (role ambiguity has asignificant negative effect on commitment to the independence of internal auditors. While basedon simultaneous test (F test, role conflict (role conflict and role ambiguity (role ambiguity havean influence on the commitment of internal auditor independence.

Rainbow-shift mechanism behind discrete optical-potential ambiguities

International Nuclear Information System (INIS)

Brandan, M.E.; McVoy, K.W.

1991-01-01

Some years ago, Drisko et al. suggested that the discrete ambiguity often encountered for elastic scattering optical potentials could be understood as being due to the interior or small-l S-matrix elements for two ''equivalent'' potentials differing in phase by 2π, l-by-l. We point out that the absence of this phase change for peripheral partial waves is equally essential, and suggest that a deeper understanding of the ambiguity may be achieved by viewing it as a consequence of a farside interference between interior and peripheral partial waves. It is this interference which produces the broad ''Airy maxima'' of a nuclear rainbow, and we show that a Drisko-type phase-shift increment δ l →(δ l +π) for low-l phases relative to the high-l ones is exactly what is needed to shift a farside rainbow pattern by one Airy maximum, thus providing an equivalent ''rainbow-shift'' interpretation of the discrete ambiguity. The physical importance of both interpretations lies in the fact that the existence of discrete ambiguities (as well as of nuclear rainbows) is explicit evidence for low-l transparency in nucleus-nucleus collisions. The essential role played by low partial waves explains why peripheral reactions have generally not proven helpful in resolving this ambiguity

Perceived ambiguity as a barrier to intentions to learn genome sequencing results.

Science.gov (United States)

Taber, Jennifer M; Klein, William M P; Ferrer, Rebecca A; Han, Paul K J; Lewis, Katie L; Biesecker, Leslie G; Biesecker, Barbara B

2015-10-01

Many variants that could be returned from genome sequencing may be perceived as ambiguous-lacking reliability, credibility, or adequacy. Little is known about how perceived ambiguity influences thoughts about sequencing results. Participants (n = 494) in an NIH genome sequencing study completed a baseline survey before sequencing results were available. We examined how perceived ambiguity regarding sequencing results and individual differences in medical ambiguity aversion and tolerance for uncertainty were associated with cognitions and intentions concerning sequencing results. Perceiving sequencing results as more ambiguous was associated with less favorable cognitions about results and lower intentions to learn and share results. Among participants low in tolerance for uncertainty or optimism, greater perceived ambiguity was associated with lower intentions to learn results for non-medically actionable diseases; medical ambiguity aversion did not moderate any associations. Results are consistent with the phenomenon of "ambiguity aversion" and may influence whether people learn and communicate genomic information.

Cognitive Flexibility Supports Preschoolers' Detection of Communicative Ambiguity

Science.gov (United States)

Gillis, Randall; Nilsen, Elizabeth S.

2014-01-01

To become successful communicators, children must be sensitive to the clarity/ambiguity of language. Significant gains in children's ability to detect communicative ambiguity occur during the early school-age years. However, little is known about the cognitive abilities that support this development. Relations between cognitive flexibility and…

On the ambiguity in relativistic tidal deformability

Science.gov (United States)

Gralla, Samuel E.

2018-04-01

The LIGO collaboration recently reported the first gravitational-wave constraints on the tidal deformability of neutron stars. I discuss an inherent ambiguity in the notion of relativistic tidal deformability that, while too small to affect the present measurement, may become important in the future. I propose a new way to understand the ambiguity and discuss future prospects for reliably linking observed gravitational waveforms to compact object microphysics.

Relation between nonlinear models and gauge ambiguities

International Nuclear Information System (INIS)

Balachandran, A.P.; Ramachandran, R.; Rupertsberger, H.; Skagerstam, B.S.

1980-01-01

We show that the solutions of a class of nonlinear models also generate gauge ambiguities in the vacuum sector of Yang-Mills theories. Our results extend known connections between gauge ambiguities and certain nonlinear sigma-models, and clarify the underlying group theory. For many nonlinear models, we also give a simple, intrinsic parametrization of physical fields (which have values in a homogeneous space of a group). (orig.)

Nonlinear Suppression of Range Ambiguity in Pulse Doppler Radar

National Research Council Canada - National Science Library

Anderson, Jon

2001-01-01

... ambiguities in Doppler and range. First introduced by Palermo in 1962 using two conjugate LFM pulses, the primary nonlinear suppression objective involves reducing range ambiguity, given the waveform is nominally unambiguous...

[Cosmetic surgery of the male genitalia].

Science.gov (United States)

Chevallier, D; Haertig, A; Faix, A; Droupy, S

2013-07-01

To describe the indications and results of techniques to change the appearance of the penis for aesthetic reasons. Provide recommendations concerning cosmetic surgery of the male genitalia. We have selected from Medline Database, articles published between 1990 and 2011. Forty articles have been selected excluding papers reporting populations less than five cases per type of procedure. There is no consensus on the size below which it is justifiable to accept or attempt to modify the size of the penis. Length of the penis in maximal tension less than 9.5 cm or 10 cm in erection can be considered as an acceptable limit, in a patient who suffers from it. The assessment of men asking for penile enlargement must include a psychosexological or psychiatric evaluation, looking for a dysmorphophobia or another psychiatric condition. Penile extenders under medical control must be the first-line treatment option for patient seeking penile lenghtening procedure when justified. In case of failure, three techniques can be used alone or in combination: penile lengthening by section of the suspensory ligaments and suprapubic skin advancement, lipectomy of Mons pubis and scrotal webbing section. The results are modest, the rate of complications significant and satisfaction low. Girth enlargement techniques by injection of autologous fat give inconsistent aesthetic results and satisfaction rates are low. All other techniques remain experimental. Cosmetic surgery of the penis is associated with a high risk of forensic exposure and surgery should be only proposed after a multidisciplinary consensus, followed by a time of reflection given to the patient after full disclosure. Applications for the purpose of reconstruction surgery after trauma or consequences of cancer treatment are justified. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

An Investigation into Ambiguity Tolerance in Iranian Senior EFL Undergraduates

Science.gov (United States)

Marzban, Amin; Barati, Hossein; Moinzadeh, Ahmad

2012-01-01

The present study aimed to explore how tolerant of ambiguity Iranian EFL learners at university level are and if gender plays a role in this regard. To this end, upon filling in the revised SLTAS scale of ambiguity tolerance 194 male and female Iranian teacher trainees were assigned to three ambiguity tolerance groups; namely, high, moderate and…

Robust portfolio choice with ambiguity and learning about return predictability

DEFF Research Database (Denmark)

Larsen, Linda Sandris; Branger, Nicole; Munk, Claus

2013-01-01

We analyze the optimal stock-bond portfolio under both learning and ambiguity aversion. Stock returns are predictable by an observable and an unobservable predictor, and the investor has to learn about the latter. Furthermore, the investor is ambiguity-averse and has a preference for investment...... strategies that are robust to model misspecifications. We derive a closed-form solution for the optimal robust investment strategy. We find that both learning and ambiguity aversion impact the level and structure of the optimal stock investment. Suboptimal strategies resulting either from not learning...... or from not considering ambiguity can lead to economically significant losses....

Sensory memory for ambiguous vision.

Science.gov (United States)

Pearson, Joel; Brascamp, Jan

2008-09-01

In recent years the overlap between visual perception and memory has shed light on our understanding of both. When ambiguous images that normally cause perception to waver unpredictably are presented briefly with intervening blank periods, perception tends to freeze, locking into one interpretation. This indicates that there is a form of memory storage across the blank interval. This memory trace codes low-level characteristics of the stored stimulus. Although a trace is evident after a single perceptual instance, the trace builds over many separate stimulus presentations, indicating a flexible, variable-length time-course. This memory shares important characteristics with priming by non-ambiguous stimuli. Computational models now provide a framework to interpret many empirical observations.

Ambiguity resolution in systems using Omega for position location

Science.gov (United States)

Frenkel, G.; Gan, D. G.

1974-01-01

The lane ambiguity problem prevents the utilization of the Omega system for many applications such as locating buoys and balloons. The method of multiple lines of position introduced herein uses signals from four or more Omega stations for ambiguity resolution. The coordinates of the candidate points are determined first through the use of the Newton iterative procedure. Subsequently, a likelihood function is generated for each point, and the ambiguity is resolved by selecting the most likely point. The method was tested through simulation.

A Lexical Analysis Tool with Ambiguity Support

OpenAIRE

Quesada, Luis; Berzal, Fernando; Cortijo, Francisco J.

2012-01-01

Lexical ambiguities naturally arise in languages. We present Lamb, a lexical analyzer that produces a lexical analysis graph describing all the possible sequences of tokens that can be found within the input string. Parsers can process such lexical analysis graphs and discard any sequence of tokens that does not produce a valid syntactic sentence, therefore performing, together with Lamb, a context-sensitive lexical analysis in lexically-ambiguous language specifications.

Comparative anatomy of the female genitalia of generic-level taxa in tribe Aedini (Diptera: Culicidae). Part XXXVII. Genus Bifidistylus Reinert, Harbach and Kitching

Science.gov (United States)

A comparative, morphological analysis of the female genitalia of species included in genus Bifidistylus Reinert, Harbach and Kitching was conducted. Treatment of the genital morphology of the genus includes a composite description of the genus, a detailed description and illustration of the type sp...

Decision ambiguity is mediated by a late positive potential originating from cingulate cortex.

Science.gov (United States)

Sun, Sai; Zhen, Shanshan; Fu, Zhongzheng; Wu, Daw-An; Shimojo, Shinsuke; Adolphs, Ralph; Yu, Rongjun; Wang, Shuo

2017-08-15

People often make decisions in the face of ambiguous information, but it remains unclear how ambiguity is represented in the brain. We used three types of ambiguous stimuli and combined EEG and fMRI to examine the neural representation of perceptual decisions under ambiguity. We identified a late positive potential, the LPP, which differentiated levels of ambiguity, and which was specifically associated with behavioral judgments about choices that were ambiguous, rather than passive perception of ambiguous stimuli. Mediation analyses together with two further control experiments confirmed that the LPP was generated only when decisions are made (not during mere perception of ambiguous stimuli), and only when those decisions involved choices on a dimension that is ambiguous. A further control experiment showed that a stronger LPP arose in the presence of ambiguous stimuli compared to when only unambiguous stimuli were present. Source modeling suggested that the LPP originated from multiple loci in cingulate cortex, a finding we further confirmed using fMRI and fMRI-guided ERP source prediction. Taken together, our findings argue for a role of an LPP originating from cingulate cortex in encoding decisions based on task-relevant perceptual ambiguity, a process that may in turn influence confidence judgment, response conflict, and error correction. Copyright © 2017 Elsevier Inc. All rights reserved.

Ambiguity tolerance in organizations: definitional clarification and perspectives on future research.

Science.gov (United States)

McLain, David L; Kefallonitis, Efstathios; Armani, Kimberly

2015-01-01

Ambiguity tolerance is an increasingly popular subject for study in a wide variety of fields. The definition of ambiguity tolerance has changed since its inception, and accompanying that change are changes in measurement and the research questions that interest researchers. There is a wealth of opportunity for research related to ambiguity tolerance and recent advances in neuroscience, measurement, trait research, perception, problem solving, and other fields highlight areas of interest and point to issues that need further attention. The future of ambiguity tolerance research is promising and it is expected that future studies will yield new insights into individual differences in reactions to the complex, unfamiliar, confusing, indeterminate, and incomplete stimuli that fall within the conceptual domain of ambiguity.

Finding meaning in art: Preferred levels of ambiguity in art appreciation

Science.gov (United States)

Jakesch, Martina; Leder, Helmut

2011-01-01

Uncertainty is typically not desirable in everyday experiences, but uncertainty in the form of ambiguity may be a defining feature of aesthetic experiences of modern art. In this study, we examined different hypotheses concerning the quantity and quality of information appreciated in art. Artworks were shown together with auditorily presented statements. We tested whether the amount of information, the amount of matching information, or the proportion of matching to nonmatching statements apparent in a picture (levels of ambiguity) affect liking and interestingness. Only the levels of ambiguity predicted differences in the two dependent variables. These findings reveal that ambiguity is an important determinant of aesthetic appreciation and that a certain level of ambiguity is appreciable. PMID:19565431

Children's Comprehension of Two Types of Syntactic Ambiguity

Science.gov (United States)

Zimmer, Elly Jane

2017-01-01

This study asks whether children accept both interpretations of ambiguous sentences with contexts supporting each option. Twenty-six 3- to 5-year-old English-speaking children and a control group of 30 English-speaking adults participated in a truth value judgment task. As a step towards evaluating the complexity of syntactic ambiguity, the…

Ambiguous sets of partial wave amplitudes can intersect

International Nuclear Information System (INIS)

Kok, L.P.; Roo, M. de

1976-01-01

Continuation in energy as a method to resolve ambiguities in phase-shift analysis is discussed. It is shown that continuity in energy is not in all cases sufficient to resolve ambiguities, and examples are given of such cases for both spin 0 - spin 0 and spin 0 - spin 1/2 scattering. (author)

Primary cutaneous lymphoma with involvement of external genitalia

International Nuclear Information System (INIS)

Viscandi, C.; Campo, L. del

1998-01-01

We describe the radiological findings recorded in a case of primary B cells cutaneous lymphoma that presented with involvement of penis and scrotum. The patient was referred to our center to undergo an ultrasonographic study. (Author) 7 refs

Development of a New Scale to Measure Ambiguity Tolerance in Veterinary Students.

Science.gov (United States)

Hammond, Jennifer A; Hancock, Jason; Martin, Margaret S; Jamieson, Susan; Mellor, Dominic J

The ability to cope with ambiguity and feelings of uncertainty is an essential part of professional practice. Research with physicians has identified that intolerance of ambiguity or uncertainty is linked to stress, and some authors have hypothesized that there could be an association between intolerance of ambiguity and burnout. We describe the adaptation of the TAMSAD (Tolerance of Ambiguity in Medical Students and Doctors) scale for use with veterinary students. Exploratory factor analysis supports a uni-dimensional structure for the Ambiguity tolerance construct. Although internal reliability of the 29-item TAMSAD scale is reasonable (α=.50), an alternative 27-item scale (drawn from the original 41 items used to develop TAMSAD) shows higher internal reliability for veterinary students (α=.67). We conclude that there is good evidence to support the validity of this latter TAVS (Tolerance of Ambiguity in Veterinary Students) scale to study ambiguity tolerance in veterinary students.

Profile of disorders of sexual differentiation in the Northeast region of ...

African Journals Online (AJOL)

In our study, 32.26% presented with primary female infertility, 27.86% adolescent girls presented with primary amenorrhea, 16.29% presented with male infertility, 10.35% presented with ambiguous genitalia at birth or soon afterward, 6.60% were females who presented with delayed 2ry sexual characters and short stature, ...

Role of magnetic resonance imaging in assigning sex in an ...

African Journals Online (AJOL)

A three years old child with ambiguous genitalia since birth had been referred to Muhimbili National Hospital (MNH),a tertiary referral hospital, in order to be evaluated and assigned sex correctly. Due to periphery location of the referring center, social and economic constraints, the child was not presented earlier. Physical ...

Serum concentrations of Anti-Müllerian Hormone (AMH) in 95 patients with Klinefelter syndrome with or without cryptorchidism

DEFF Research Database (Denmark)

Aksglaede, Lise; Christiansen, Peter; Sørensen, Kaspar

2011-01-01

Aim: Anti-Müllerian hormone (AMH) is produced by foetal Sertoli cells at the time of sexual differentiation and is responsible for the regression of the Müllerian ducts in the male foetus. AMH is a testis-specific marker of diagnostic value in infants with ambiguous genitalia or with bilateral...

An ambiguity in one-loop quantum gravity

International Nuclear Information System (INIS)

Capper, D.M.; Kimber, D.P.

1980-01-01

It is argued that the application of the dimensional regularisation technique to one-loop quantum gravity calculations is ambiguous. However, for the calculation of on-mass-shell S-matrix elements, this ambiguity can be resolved by requiring consistency with results obtained from other regularisation schemes. Some discussion is also given of the implications of this work for recent attempts to use higher derivative Lagrangians to solve the renormalisability problem in quantum gravity. (author)

Generalized dynamic model and control of ambiguous mono axial vehicle robot

Directory of Open Access Journals (Sweden)

Frantisek Duchon

2016-09-01

Full Text Available This article deals with the novel concept of ambiguous mono axial vehicle robot. Such robot is a combination of Segway and dicycle, which utilizes the advantages of each chassis. The advantage of dicycle is lower energy consumption during the movement and the higher safety of carried payload. The movable platform inside the ambiguous mono axial vehicle allows using the various sensors or devices. This will change the ambiguous mono axial vehicle to the Segway type robot. Both these modes are necessary to control in the stable mode to ensure the safety of the ambiguous mono axial vehicle’s movement. The main contents of the article contain description of generalized dynamic model of ambiguous mono axial vehicle and related control of ambiguous mono axial vehicle. The proposal is unique in that the same controller is used for both modes. Several simulations verify proposed control schemes and identified parameters. Moreover, the dicycle type of platform has never been used in robotics and that is another novelty.

Scheme-scale ambiguity in analysis of QCD observable

International Nuclear Information System (INIS)

Mirjalili, A.; Kniehl, B.A.

2010-01-01

The scheme-scale ambiguity that has plagued perturbative analysis in QCD remains on obstacle to making precise tests of the theory. Many attempts have been done to resolve the scale ambiguity. In this regard the BLM, EC, PMS and CORGI approaches are more distinct. We try to employ these methods to fix the scale ambiguity at NLO, NNLO and even in more higher order approximations. By optimizing the renormalization scale, there will be a possibility to predicate higher order terms. We present general results for predicted terms at any order, using different optimization methods. Some observable as specific examples will be used to indicate the validity of scale fixing to predicate the higher order terms. (authors)

A method of undifferenced ambiguity resolution for GPS+GLONASS precise point positioning.

Science.gov (United States)

Yi, Wenting; Song, Weiwei; Lou, Yidong; Shi, Chuang; Yao, Yibin

2016-05-25

Integer ambiguity resolution is critical for achieving positions of high precision and for shortening the convergence time of precise point positioning (PPP). However, GLONASS adopts the signal processing technology of frequency division multiple access and results in inter-frequency code biases (IFCBs), which are currently difficult to correct. This bias makes the methods proposed for GPS ambiguity fixing unsuitable for GLONASS. To realize undifferenced GLONASS ambiguity fixing, we propose an undifferenced ambiguity resolution method for GPS+GLONASS PPP, which considers the IFCBs estimation. The experimental result demonstrates that the success rate of GLONASS ambiguity fixing can reach 75% through the proposed method. Compared with the ambiguity float solutions, the positioning accuracies of ambiguity-fixed solutions of GLONASS-only PPP are increased by 12.2%, 20.9%, and 10.3%, and that of the GPS+GLONASS PPP by 13.0%, 35.2%, and 14.1% in the North, East and Up directions, respectively.

Ambiguity and Investment Decisions: An Empirical Analysis on Mutual Fund Investor Behaviour

Directory of Open Access Journals (Sweden)

Chao Tang

2017-09-01

Full Text Available The paper empirically studies the relationship between ambiguity and mutual fund investor behaviour. Theoretical models for investment decisions incorporating ambiguity motivate our analyses. While the models indicate that investors would less likely to invest in financial markets when ambiguity increases, there is rare empirical evidence in natural occurring financial data to examine this hypothesis. In this paper, we test the hypothesis with equity fund flow data as for investment decisions and ambiguity with the degree of disagreement in equity analysts’ prediction about asset returns. Our results support the hypothesis that increases in ambiguity could lead to less fund flows and this result remains consistently when adding various control variables affecting fund flows. Besides, we find that heterogeneous impacts of ambiguity: equity funds with high yield targets and active management style are affected more than funds investing in stable stocks; funds with larger proportion of institutional investors are more sensitive and affected by the ambiguity.

Ambiguities of the phase analysis of the proton-proton scattering amplitude

International Nuclear Information System (INIS)

Grebenyuk, O.G.; Shklyarevskij, G.M.

1980-01-01

Ambiguities of the phase analysis of the proton-proton scattering amplitude are analysed. It is shown that for five measurements of polarization parameters sets there are ambiguities similar to the Gersten ambiguities in the phase analysis of πN scattering. A problem on additional experiments needed to eliminate these ambiguities is investigated. It is shown that for this purpose it suffices to measure three total cross sections with polarized and nonpolarized protons, thus determining the imaginary parts of amplitudes at THETA=0 and polarization parameters

Ambiguity Tolerance in Organizations: Definitional Clarification and Perspectives on Future Research

Directory of Open Access Journals (Sweden)

David L Mclain

2015-04-01

Full Text Available Ambiguity tolerance is an increasingly popular subject for study in a wide variety of fields. The definition of ambiguity tolerance has changed since its inception, and accompanying that change are changes in measurement and the research questions that interest researchers. There is a wealth of opportunity for research related to ambiguity tolerance and recent advances in neuroscience, measurement, trait research, perception, problem solving, and other fields highlight areas of interest and point to issues that need further attention. The future of ambiguity tolerance research is promising and it is expected that future studies will yield new insights into individual differences in reactions to the complex, unfamiliar, confusing, indeterminate, and incomplete stimuli that fall within the conceptual domain of ambiguity.

Ambiguity in urban belonging

DEFF Research Database (Denmark)

Koefoed, Lasse Martin; Simonsen, Kirsten

2015-01-01

mapping of life as an ethnic minority in the city. It revolves around three issues. First, it focuses on the narrators’ experiences of exclusions and blockages in everyday life. This is followed by a focus on urban belonging emphasizing its differential character. Finally, the ambiguity of experiences...

Crichton's phase-shift ambiguity

NARCIS (Netherlands)

Atkinson, D.; Johnson, P.W.; Mehta, N.; Roo, M. de

1973-01-01

A re-examination of the SPD phase-shift ambiguity is made with a view to understanding certain singular features of the elastic unitarity constraint. An explicit solution of Crichton's equations is presented, and certain features of this solution are displayed graphically. In particular, it is shown

Ambiguity and Nominal Group Multiple Post modification in the ...

African Journals Online (AJOL)

Administrator

students of The Federal Polytechnic, Ede, Nigeria offering. English courses as .... “a piece of land along a river” or “a place for keeping money and valuables”. ... ambiguity. Attachment ambiguity occurs when a modifier may be logically or ...

Ambiguity of non-systematic chemical identifiers within and between small-molecule databases.

Science.gov (United States)

Akhondi, Saber A; Muresan, Sorel; Williams, Antony J; Kors, Jan A

2015-01-01

A wide range of chemical compound databases are currently available for pharmaceutical research. To retrieve compound information, including structures, researchers can query these chemical databases using non-systematic identifiers. These are source-dependent identifiers (e.g., brand names, generic names), which are usually assigned to the compound at the point of registration. The correctness of non-systematic identifiers (i.e., whether an identifier matches the associated structure) can only be assessed manually, which is cumbersome, but it is possible to automatically check their ambiguity (i.e., whether an identifier matches more than one structure). In this study we have quantified the ambiguity of non-systematic identifiers within and between eight widely used chemical databases. We also studied the effect of chemical structure standardization on reducing the ambiguity of non-systematic identifiers. The ambiguity of non-systematic identifiers within databases varied from 0.1 to 15.2 % (median 2.5 %). Standardization reduced the ambiguity only to a small extent for most databases. A wide range of ambiguity existed for non-systematic identifiers that are shared between databases (17.7-60.2 %, median of 40.3 %). Removing stereochemistry information provided the largest reduction in ambiguity across databases (median reduction 13.7 percentage points). Ambiguity of non-systematic identifiers within chemical databases is generally low, but ambiguity of non-systematic identifiers that are shared between databases, is high. Chemical structure standardization reduces the ambiguity to a limited extent. Our findings can help to improve database integration, curation, and maintenance.

Good luck, bad luck, and ambiguity aversion

OpenAIRE

Briony D. Pulford; Poonam Gill

2014-01-01

We report a series of experiments investigating the influence of feeling lucky or unlucky on people's choice of known-risk or ambiguous options using the traditional Ellsberg Urns decision-making task. We induced a state of feeling lucky or unlucky in subjects by using a rigged wheel-of-fortune game, which just missed either the bankrupt or the jackpot outcome. In the first experiment a large reversal of the usual ambiguity aversion effect was shown, indicating that feeling ...

Quantization ambiguity and non-trivial vacuum structure

International Nuclear Information System (INIS)

Rothe, H.J.; Swieca, J.A.

1978-01-01

It is pointed out that there is an ambiguity in quantization of any system whose configuration space has a non-trivial topology characterized by a Chern number. In field theories this ambiguity manifests itself through the existence of theta-sectors. The point of view adopted gives a simple interpretation of the difference between the temporal and Coulomb gauge descriptions of instantons. The general ideas are exemplified in the O(3) non-linear sigma-model in two dimensions [pt

Attitudes toward risk and ambiguity in patients with autism spectrum disorder.

Science.gov (United States)

Fujino, Junya; Tei, Shisei; Hashimoto, Ryu-Ichiro; Itahashi, Takashi; Ohta, Haruhisa; Kanai, Chieko; Okada, Rieko; Kubota, Manabu; Nakamura, Motoaki; Kato, Nobumasa; Takahashi, Hidehiko

2017-01-01

Although the ability to make optimal decisions under uncertainty is an integral part of everyday life, individuals with autism spectrum disorder (ASD) frequently report that they experience difficulties with this skill. In behavioral economics, researchers distinguish two types of uncertainty to understand decision-making in this setting: risk (known probabilities) and ambiguity (unknown probabilities). However, it remains unclear how individuals with ASD behave under risk and ambiguity, despite growing evidence of their altered decision-making under uncertainty. We therefore extended previous research by studying the attitudes of those with ASD toward risk and ambiguity in both positive and negative contexts (i.e., gain and loss). In gain contexts, no significant difference was observed between the groups in risk attitudes, but ambiguity aversion was attenuated in ASD. In loss contexts, ambiguity attitudes did not significantly differ between the groups, but the ASD participants were less risk-seeking compared with the controls. In addition, insensitivity to the context change under risk and ambiguity in ASD was both significantly associated with poor social skills. These results improve our understanding of altered decision-making under uncertainty by disentangling the attitudes toward risk and ambiguity in ASD individuals. Applying behavioral economic tools may provide insights into the mechanisms underlying behavioral disturbances in ASD.

Computational Humour : Utilizing Cross-Reference Ambiguity for Conversational Jokes

NARCIS (Netherlands)

Tinholt, Hans Wim; Nijholt, Anton; Masulli, Francesco; Mitra, Sushmita; Pasi, Gabriella

2007-01-01

This paper presents a computer implementation that utilizes cross-reference ambiguity in utterances for simple conversational jokes. The approach is based on the SSTH. Using a simple script representation, it is shown that cross-reference ambiguities always satisfy the SSTH requirement for script

Roles of frontal and temporal regions in reinterpreting semantically ambiguous sentences

Directory of Open Access Journals (Sweden)

Sylvia eVitello

2014-07-01

Full Text Available Semantic ambiguity resolution is an essential and frequent part of speech comprehension because many words map onto multiple meanings (e.g., bark, bank. Neuroimaging research highlights the importance of the left inferior frontal gyrus (LIFG and the left posterior temporal cortex in this process but the roles they serve in ambiguity resolution are uncertain. One possibility is that both regions are engaged in the processes of semantic reinterpretation that follows incorrect interpretation of an ambiguous word. Here we used fMRI to investigate this hypothesis. 20 native British English monolinguals were scanned whilst listening to sentences that contained an ambiguous word. To induce semantic reinterpretation, the disambiguating information was presented after the ambiguous word and delayed until the end of the sentence (e.g., the teacher explained that the BARK was going to be very damp. These sentences were compared to well-matched unambiguous sentences. Supporting the reinterpretation hypothesis, these ambiguous sentences produced more activation in both the LIFG and the left posterior inferior temporal cortex. Importantly, all but one subject showed ambiguity-related peaks within both regions, demonstrating that the group-level results were driven by high inter-subject consistency. Further support came from the finding that activation in both regions was modulated by meaning dominance. Specifically, sentences containing biased ambiguous words, which have one more dominant meaning, produced greater activation than those with balanced ambiguous words, which have two equally frequent meanings. Because the context always supported the less frequent meaning, the biased words require reinterpretation more often than balanced words. This is the first evidence of dominance effects in the spoken modality and provides strong support that frontal and temporal regions support the updating of semantic representations during speech comprehension.

The Learning Teacher: Role of Ambiguity in Education

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Suzawa, Gilbert S.

2013-01-01

Life is full of ambiguities, but as teachers we generally try to teach our students in a manner that sanitizes knowledge of all of its ambiguities. In doing so, we create an educational environment which forces students to learn in a rather meaningless fashion and this in turn leads to a lack of vitality and relevance within the academy. This need…

Attitude Toward Ambiguity: Empirically Robust Factors in Self-Report Personality Scales.

Science.gov (United States)

Lauriola, Marco; Foschi, Renato; Mosca, Oriana; Weller, Joshua

2016-06-01

Two studies were conducted to examine the factor structure of attitude toward ambiguity, a broad personality construct that refers to personal reactions to perceived ambiguous stimuli in a variety of context and situations. Using samples from two countries, Study 1 mapped the hierarchical structure of 133 items from seven tolerance-intolerance of ambiguity scales (N = 360, Italy; N = 306, United States). Three major factors-Discomfort with Ambiguity, Moral Absolutism/Splitting, and Need for Complexity and Novelty-were recovered in each country with high replicability coefficients across samples. In Study 2 (N = 405, Italian community sample; N =366, English native speakers sample), we carried out a confirmatory analysis on selected factor markers. A bifactor model had an acceptable fit for each sample and reached the construct-level invariance for general and group factors. Convergent validity with related traits was assessed in both studies. We conclude that attitude toward ambiguity can be best represented a multidimensional construct involving affective (Discomfort with Ambiguity), cognitive (Moral Absolutism/Splitting), and epistemic (Need for Complexity and Novelty) components. © The Author(s) 2015.

Synergistic Disruption of External Male Sex Organ Development by a Mixture of Four Antiandrogens

DEFF Research Database (Denmark)

Christiansen, Sofie; Scholze, Martin; Dalgaard, Majken

2009-01-01

: Strikingly, the effect of combined exposure to the selected chemicals on malformations of external sex organs was synergistic, and the observed responses were greater than would be predicted from the toxicities of the individual chemicals. In relation to other hallmarks of disrupted male sexual development......, and a pharmaceutical, finasteride, on landmarks of male sexual development in the rat, including changes in anogenital distance, retained nipples, sex organ weights and malformations of genitalia. These chemicals were chosen because they disrupt androgen action according to differing mechanisms of action. Results...... in male offspring. Conclusions: Since unhindered androgen action is essential for human male development in foetal life, these findings are highly relevant to human risk assessment. Evaluations that ignore the possibility of combination effects may lead to considerable underestimations of risks associated...

Semantic ambiguity effects on traditional Chinese character naming: A corpus-based approach.

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Chang, Ya-Ning; Lee, Chia-Ying

2017-11-09

Words are considered semantically ambiguous if they have more than one meaning and can be used in multiple contexts. A number of recent studies have provided objective ambiguity measures by using a corpus-based approach and have demonstrated ambiguity advantages in both naming and lexical decision tasks. Although the predictive power of objective ambiguity measures has been examined in several alphabetic language systems, the effects in logographic languages remain unclear. Moreover, most ambiguity measures do not explicitly address how the various contexts associated with a given word relate to each other. To explore these issues, we computed the contextual diversity (Adelman, Brown, & Quesada, Psychological Science, 17; 814-823, 2006) and semantic ambiguity (Hoffman, Lambon Ralph, & Rogers, Behavior Research Methods, 45; 718-730, 2013) of traditional Chinese single-character words based on the Academia Sinica Balanced Corpus, where contextual diversity was used to evaluate the present semantic space. We then derived a novel ambiguity measure, namely semantic variability, by computing the distance properties of the distinct clusters grouped by the contexts that contained a given word. We demonstrated that semantic variability was superior to semantic diversity in accounting for the variance in naming response times, suggesting that considering the substructure of the various contexts associated with a given word can provide a relatively fine scale of ambiguity information for a word. All of the context and ambiguity measures for 2,418 Chinese single-character words are provided as supplementary materials.

A method to reduce ambiguities of qualitative reasoning for conceptual design applications

NARCIS (Netherlands)

D'Amelio, V.; Chmarra, M.K.; Tomiyama, T.

2013-01-01

Qualitative reasoning can generate ambiguous behaviors due to the lack of quantitative information. Despite many different research results focusing on ambiguities reduction, fundamentally it is impossible to totally remove ambiguities with only qualitative methods and to guarantee the consistency

Ambiguous Loss in a Non-Western Context: Families of the Disappeared in Postconflict Nepal

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Robins, Simon

2010-01-01

Ambiguous loss has become a standard theory for understanding the impact of situations where the presence of a family member is subject to ambiguity. A number of studies of ambiguous loss have been made in a range of situations of ambiguity, but almost all have been firmly located within a Western cultural context. Here, ambiguous loss is explored…

SAR Cross-Ambiguities in SAOCOM-CS Large Baseline Bistatic Configuration

OpenAIRE

Bordoni, Federica; Rodriguez-Cassola, Marc; Younis, Marwan; Prats-Iraola, Pau; Lopez-Dekker, Paco; Krieger, Gerhard

2016-01-01

The evaluation of the ambiguous signal level, the Ambiguity-to-Signal Ratio (ASR), plays a key role in the Synthetic Aperture Radar (SAR) design and performance prediction. In conventional SAR acquisition scenarios, the computation of the ASR is based on the evaluation of the range and azimuth ambiguous contributes. Though appealing for its simplicity, this approach could be inaccurate in case of complex SAR acquisition geometries. In this paper we focus on the ASR performance of the SAOCOM-...

Discriminating Between Models of Ambiguity Attitude : A Qualitative Test

NARCIS (Netherlands)

Cubitt, Robin; van de Kuilen, Gijs; Mukerji, Sujoy

The exchange between Epstein (2010) and Klibanoff et al. (2012) identified a behavioral issue that sharply distinguishes between two classes of models of ambiguity sensitivity, exemplified by the 훼- MEU model and the smooth ambiguity model, respectively. The issue in question is whether a subject’s

Neural responses to ambiguity involve domain-general and domain-specific emotion processing systems.

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Neta, Maital; Kelley, William M; Whalen, Paul J

2013-04-01

Extant research has examined the process of decision making under uncertainty, specifically in situations of ambiguity. However, much of this work has been conducted in the context of semantic and low-level visual processing. An open question is whether ambiguity in social signals (e.g., emotional facial expressions) is processed similarly or whether a unique set of processors come on-line to resolve ambiguity in a social context. Our work has examined ambiguity using surprised facial expressions, as they have predicted both positive and negative outcomes in the past. Specifically, whereas some people tended to interpret surprise as negatively valenced, others tended toward a more positive interpretation. Here, we examined neural responses to social ambiguity using faces (surprise) and nonface emotional scenes (International Affective Picture System). Moreover, we examined whether these effects are specific to ambiguity resolution (i.e., judgments about the ambiguity) or whether similar effects would be demonstrated for incidental judgments (e.g., nonvalence judgments about ambiguously valenced stimuli). We found that a distinct task control (i.e., cingulo-opercular) network was more active when resolving ambiguity. We also found that activity in the ventral amygdala was greater to faces and scenes that were rated explicitly along the dimension of valence, consistent with findings that the ventral amygdala tracks valence. Taken together, there is a complex neural architecture that supports decision making in the presence of ambiguity: (a) a core set of cortical structures engaged for explicit ambiguity processing across stimulus boundaries and (b) other dedicated circuits for biologically relevant learning situations involving faces.

Resolution of ambiguities in perturbative QCD

International Nuclear Information System (INIS)

Nakkagawa, Hisao; Niegawa, Akira.

1984-01-01

In the perturbative QCD analyses of the deeply inelastic processes, the coupling constant depends on at least two mass-scales, the renormalization scale and the factorization scale. By integrating the coupled renormalization group equations with respect to these two mass-scales, the running coupling constant is defined. A perturbative approximation then introduces a new ambiguity, the integration-path dependence, into the theory. We show that the problem of this new ambiguity is resolved by imposing Stevenson's principle of minimal sensitivity. Together with the analogous analysis of the operator matrix element or the cut vertex, we can completely solve the problem of getting an unambiguous perturbative QCD prediction. (author)

Increasing Statistical Literacy by Exploiting Lexical Ambiguity of Technical Terms

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Jennifer Kaplan

2018-01-01

Full Text Available Instructional inattention to language poses a barrier for students in entry-level science courses, in part because students may perceive a subject as difficult solely based on the lack of understanding of the vocabulary. In addition, the technical use of terms that have different everyday meanings may cause students to misinterpret statements made by instructors, leading to an incomplete or incorrect understanding of the domain. Terms that have different technical and everyday meanings are said to have lexical ambiguity and statistics, as a discipline, has many lexically ambiguous terms. This paper presents a cyclic process for designing activities to address lexical ambiguity in statistics. In addition, it describes three short activities aimed to have high impact on student learning associated with two different lexically ambiguous words or word pairs in statistics. Preliminary student-level data are used to assess the efficacy of the activities, and future directions for development of activities and research about lexical ambiguity in statistics in particular and STEM in general are discussed.

Preferences for 'New' Treatments Diminish in the Face of Ambiguity.

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Harrison, Mark; Marra, Carlo A; Bansback, Nick

2017-06-01

New products usually offer advantages over existing products, but in health care, most new drugs are 'me-too', comparable in effectiveness and side effects to existing drugs, but with a more ambiguous evidence base around adverse effects. Despite this, new treatments drive increased health care spending, suggesting a preference for 'newness' in this setting. We explore (1) whether preferences for treatments labeled 'new' exist and (2) persist once the ambiguity in the evidence base reflecting newness is described. We use a Canadian general population sample (n = 2837) characterized by their innovativeness in adopting new products in normal markets. We found that innovators/early adopters (n = 173) had significant preferences for 'newer' treatments (B = 0.162, p = 0.038) irrespective of comparable benefits and side effects and all respondents had significant preferences for less ambiguity in benefit/side effect estimates. Notably, when 'newness' was combined with ambiguity, no significant preferences for new treatments were observed regardless of respondent innovativeness. We conclude that preferences for new products exist for some people in health care markets but disappear when the implication of ambiguity in the evidence base for new treatments is communicated. Physicians should avoid describing treatments as 'new' or be mindful to qualify the implications of 'new' treatments in terms of evidence ambiguity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

PRF Ambiguity Detrmination for Radarsat ScanSAR System

Science.gov (United States)

Jin, Michael Y.

1998-01-01

PRF ambiguity is a potential problem for a spaceborne SAR operated at high frequencies. For a strip mode SAR, there were several approaches to solve this problem. This paper, however, addresses PRF ambiguity determination algorithms suitable for a burst mode SAR system such as the Radarsat ScanSAR. The candidate algorithms include the wavelength diversity algorithm, range look cross correlation algorithm, and multi-PRF algorithm.

Confronting Ambiguity in Science

Science.gov (United States)

Emery, Katherine; Harlow, Danielle; Whitmer, Ali; Gaines, Steven

2015-01-01

People are regularly confronted with environmental and science-related issues presented to them in newspapers, on television, or even in their own doctor's office. Often the information they use to inform their decisions on matters of science may be ambiguous and contradictory. This article presents an activity that investigates how students deal…

Li Shangyin and the Art of Poetic Ambiguity

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Maja Lavrač

2016-12-01

Full Text Available Li Shangyin (813–858, one of the most respected, mysterious, ambiguous and provocative of Chinese poets, lived during the late Tang period, when the glorious Tang dynasty was beginning to decline. It was a time of social riots, political division and painful general insecurity. Li Shangyin is famous as a highly original and committed poet who developed a unique style full of vague allusions and unusual images derived from the literary past (the traditional canon, myths and legends as well as from nature and personal experience. The second important feature of his poetry is a mysteriousness which finally leads to ambiguity. Ambiguity plays an essential role in most of his renowned poems, and he uses it to superbly connect present and past, reality and fantasy, and history and mythology. Thus, ambiguity and obscurity, respectively, often engender different interpretations among Chinese critics. These interpretations reflect the poems’ imaginative qualities, hypotheses and contradictions. Since each interpretive direction emphasizes but a single aspect of the poet’s character, it is more fitting to understand his ambiguous poems in symbolic terms. Such understanding entails that the meaning of the poem is not limited to one interpretation; rather, the poem’s poetic landscape opens itself up to various interpretations. Li Shangyin is actually most popular for his melancholic love poetry that reveals his ambiguous attitude to love. In this poetry, love is shrouded in a secret message. On the one hand, we can sense his moral disapproval of a secret but hopeless love; on the other, we can sense his passion. This leads to a paradox: the pleasing temptations of an illicit romance also exact a high price. In these love poems Li investigates various aspects of the worlds of passion which stoke in him feelings of rapture, satisfaction, joy and hope as well as feelings of doubt, frustration, despair and even thoughts of death.

Process ambiguities in Sino-Danish Business Negotiations

DEFF Research Database (Denmark)

Kumar, Rajesh; Worm, Verner

2004-01-01

. These ambiguities stem from differences in negotiation scripts across Danish and Chinese cultures. The essential argument being advanced here is that it is the effective and/or the ineffective management of process ambiguities that shapes the evolution of the negotiating dynamic between the Danish and the Chinese...... businesspeople. An inductive model of sino-Danish negotiations is developed that is based on 24 interviews conducted with Danish expatriate managers in China and 4 interviews with Chinese working in Danish companies. Implications for research and practice are discussed...

The classification of ambiguity in polarimetric reconstruction of coronal mass ejection

International Nuclear Information System (INIS)

Dai, Xinghua; Wang, Huaning; Huang, Xin; Du, Zhanle; He, Han

2014-01-01

The Thomson scattering theory indicates that there exist explicit and implicit ambiguities in polarimetric analyses of coronal mass ejection (CME) observations. We suggest a classification for these ambiguities in CME reconstruction. Three samples, including double explicit, mixed, and double implicit ambiguity, are shown with the polarimetric analyses of STEREO CME observations. These samples demonstrate that this classification is helpful for improving polarimetric reconstruction.

U.S./Arab Reflections on Our Tolerance for Ambiguity

Science.gov (United States)

Bright, Larry K.; Mahdi, Ghada S.

2012-01-01

As the authors, a Midwestern American educational administration professor and a Middle Eastern Iraqi doctoral candidate, have continued to interact over the past 3 years, both have come to appreciate the importance of increasing their tolerance for ambiguity--ambiguities in examining cultural, linguistic, and religious customs and complexities in…

Effective potential for bilocal composite fields and its ambiguity

International Nuclear Information System (INIS)

Muta, T.

1988-01-01

It is discussed that an ambiguity exists in the definition of the effective potential for bilocal composite fields which is an indispensable tool to discuss dynamical symmetry breaking. The ambiguity gives warning to arguments on the stability of ground states based on the curvature of the effective potential

Examining English-German Translation Ambiguity Using Primed Translation Recognition

Science.gov (United States)

Eddington, Chelsea M.; Tokowicz, Natasha

2013-01-01

Many words have more than one translation across languages. Such "translation-ambiguous" words are translated more slowly and less accurately than their unambiguous counterparts. We examine the extent to which word context and translation dominance influence the processing of translation-ambiguous words. We further examine how these factors…

Quantification Scope Ambiguity Resolution: Evidence from Persian and English

Science.gov (United States)

Asadollahfam, Hassan; Lotfi, Ahmad Reza

2010-01-01

This study investigates the interpretation of scopally ambiguous sentences containing noun phrases with double quantified constituents from a processing perspective. The questions this study tried to answer were: whether or not the preferred interpretation for doubly quantified ambiguous sentences in English was influenced by English learners' L1…

Azimuth Ambiguities Removal in Littoral Zones Based on Multi-Temporal SAR Images

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Xiangguang Leng

2017-08-01

Full Text Available Synthetic aperture radar (SAR is one of the most important techniques for ocean monitoring. Azimuth ambiguities are a real problem in SAR images today, which can cause performance degradation in SAR ocean applications. In particular, littoral zones can be strongly affected by land-based sources, whereas they are usually regions of interest (ROI. Given the presence of complexity and diversity in littoral zones, azimuth ambiguities removal is a tough problem. As SAR sensors can have a repeat cycle, multi-temporal SAR images provide new insight into this problem. A method for azimuth ambiguities removal in littoral zones based on multi-temporal SAR images is proposed in this paper. The proposed processing chain includes co-registration, local correlation, binarization, masking, and restoration steps. It is designed to remove azimuth ambiguities caused by fixed land-based sources. The idea underlying the proposed method is that sea surface is dynamic, whereas azimuth ambiguities caused by land-based sources are constant. Thus, the temporal consistence of azimuth ambiguities is higher than sea clutter. It opens up the possibilities to use multi-temporal SAR data to remove azimuth ambiguities. The design of the method and the experimental procedure are based on images from the Sentinel data hub of Europe Space Agency (ESA. Both Interferometric Wide Swath (IW and Stripmap (SM mode images are taken into account to validate the proposed method. This paper also presents two RGB composition methods for better azimuth ambiguities visualization. Experimental results show that the proposed method can remove azimuth ambiguities in littoral zones effectively.

Phase ambiguity resolution for offset QPSK modulation systems

Science.gov (United States)

Nguyen, Tien M. (Inventor)

1991-01-01

A demodulator for Offset Quaternary Phase Shift Keyed (OQPSK) signals modulated with two words resolves eight possible combinations of phase ambiguity which may produce data error by first processing received I(sub R) and Q(sub R) data in an integrated carrier loop/symbol synchronizer using a digital Costas loop with matched filters for correcting four of eight possible phase lock errors, and then the remaining four using a phase ambiguity resolver which detects the words to not only reverse the received I(sub R) and Q(sub R) data channels, but to also invert (complement) the I(sub R) and/or Q(sub R) data, or to at least complement the I(sub R) and Q(sub R) data for systems using nontransparent codes that do not have rotation direction ambiguity.

Semantic Ambiguity: Do Multiple Meanings Inhibit or Facilitate Word Recognition?

Science.gov (United States)

Haro, Juan; Ferré, Pilar

2018-06-01

It is not clear whether multiple unrelated meanings inhibit or facilitate word recognition. Some studies have found a disadvantage for words having multiple meanings with respect to unambiguous words in lexical decision tasks (LDT), whereas several others have shown a facilitation for such words. In the present study, we argue that these inconsistent findings may be due to the approach employed to select ambiguous words across studies. To address this issue, we conducted three LDT experiments in which we varied the measure used to classify ambiguous and unambiguous words. The results suggest that multiple unrelated meanings facilitate word recognition. In addition, we observed that the approach employed to select ambiguous words may affect the pattern of experimental results. This evidence has relevant implications for theoretical accounts of ambiguous words processing and representation.

The Benefit of Ambiguity in Understanding Goals in Requirements Modelling

DEFF Research Database (Denmark)

Paay, Jeni; Pedell, Sonja; Sterling, Leon

2011-01-01

This paper examines the benefit of ambiguity in describing goals in requirements modelling for the design of socio-technical systems using concepts from Agent-Oriented Software Engineering (AOSE) and ethnographic and cultural probe methods from Human Computer Interaction (HCI). The authors’ aim...... ambiguity in the process of elicitation and analysis through the use of empirically informed quality goals attached to functional goals. The authors demonstrate the benefit of articulating a quality goal without turning it into a functional goal. Their study shows that quality goals kept at a high level...... of abstraction, ambiguous and open for conversations through the modelling process add richness to goal models, and communicate quality attributes of the interaction being modelled to the design phase, where this ambiguity is regarded as a resource for design....

Extent of the Immirzi ambiguity in quantum general relativity

International Nuclear Information System (INIS)

Marugan, Guillermo A Mena

2002-01-01

The Ashtekar-Barbero formulation of general relativity admits a one-parameter family of canonical transformations that preserves the expressions of the Gauss and diffeomorphism constraints. The loop quantization of the connection formalism based on each of these canonical sets leads to different predictions. This phenomenon is called the Immirzi ambiguity. It has been recently argued that this ambiguity could be generalized to the extent of a spatially dependent function instead of a parameter. This would ruin the predictability of loop quantum gravity. We prove that such expectations are not realized, so that the Immirzi ambiguity introduces exclusively a freedom in the choice of a real number. (letter to the editor)

Children's Understanding of Ambiguous Idioms and Conversational Perspective-Taking

Science.gov (United States)

Le Sourn-Bissaoui, Sandrine; Caillies, Stephanie; Bernard, Stephane; Deleau, Michel; Brule, Lauriane

2012-01-01

The aim of this study was to test the hypothesis that conversational perspective-taking is a determinant of unfamiliar ambiguous idiom comprehension. We investigated two types of ambiguous idiom, decomposable and nondecomposable expressions, which differ in the degree to which the literal meanings of the individual words contribute to the overall…

Semantic ambiguity processing in sentence context: Evidence from event-related fMRI

NARCIS (Netherlands)

Zempleni, Monika-Zita; Renken, Remco; Hoeks, John C. J.; Hoogduin, Johannes M.; Stowe, Laurie A.

2007-01-01

Lexical semantic ambiguity is the phenomenon when a word has multiple meanings (e.g. 'bank'). The aim of this event-related functional MRI study was to identify those brain areas, which are involved in contextually driven ambiguity resolution. Ambiguous words were selected which have a most

Contributions to the knowledge of Banasa Stål (Hemiptera, Heteroptera, Pentatomidae: Banasa chaca Thomas

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Thereza de Almeida Garbelotto

2011-09-01

Full Text Available Contributions to the knowledge of Banasa Stål (Hemiptera, Heteroptera, Pentatomidae: Banasa chaca Thomas. The male of Banasa chaca Thomas is described with emphasis on external and internal genitalia and the female internal genitalia is described. Banasa chaca is newly recorded from Buenos Aires Province (Argentina.

High energy collisions and the proton structure: an ambiguity

International Nuclear Information System (INIS)

Franca, H.M.

1980-01-01

It is pointed out an ambiguity in the determination of the sign of the imaginary part of the proton-proton elastic-scattering amplitude for ]t]>]t min . Some implications of such and ambiguity concerning the proton structure are discussed and finally, an experimental analysis which could solve it is suggested. (L.C.) [pt

Instructor Strategic Ambiguity: Delineation of the Construct and Development of a Measure

Science.gov (United States)

Klyukovski, Andrei A.; Medlock-Klyukovski, Amanda L.

2016-01-01

This article presents research to delineate the construct of instructor strategic ambiguity (ISA) and develop a measure. The first study analyzed instructor uses of ambiguity, identified 18 strategies, and classified them into four categories. The second study developed an Instructor Strategic Ambiguity Measure (ISAM) for the college classroom.…

Human Perception of Ambiguous Inertial Motion Cues

Science.gov (United States)

Zhang, Guan-Lu

2010-01-01

Human daily activities on Earth involve motions that elicit both tilt and translation components of the head (i.e. gazing and locomotion). With otolith cues alone, tilt and translation can be ambiguous since both motions can potentially displace the otolithic membrane by the same magnitude and direction. Transitions between gravity environments (i.e. Earth, microgravity and lunar) have demonstrated to alter the functions of the vestibular system and exacerbate the ambiguity between tilt and translational motion cues. Symptoms of motion sickness and spatial disorientation can impair human performances during critical mission phases. Specifically, Space Shuttle landing records show that particular cases of tilt-translation illusions have impaired the performance of seasoned commanders. This sensorimotor condition is one of many operational risks that may have dire implications on future human space exploration missions. The neural strategy with which the human central nervous system distinguishes ambiguous inertial motion cues remains the subject of intense research. A prevailing theory in the neuroscience field proposes that the human brain is able to formulate a neural internal model of ambiguous motion cues such that tilt and translation components can be perceptually decomposed in order to elicit the appropriate bodily response. The present work uses this theory, known as the GIF resolution hypothesis, as the framework for experimental hypothesis. Specifically, two novel motion paradigms are employed to validate the neural capacity of ambiguous inertial motion decomposition in ground-based human subjects. The experimental setup involves the Tilt-Translation Sled at Neuroscience Laboratory of NASA JSC. This two degree-of-freedom motion system is able to tilt subjects in the pitch plane and translate the subject along the fore-aft axis. Perception data will be gathered through subject verbal reports. Preliminary analysis of perceptual data does not indicate that

Bank risk, bailouts and ambiguity

NARCIS (Netherlands)

Nijskens, R.G.M.

2012-01-01

The theoretical analysis in the second part investigates the effect of liquidity assistance and bailouts on bank risk taking and liquidity choice. Furthermore, it explores the possibilities for central banks to create ambiguity about liquidity assistance, thereby influencing bank choices. The

One-shot genitalia are not an evolutionary dead end - Regained male polygamy in a sperm limited spider species

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Michalik Peter

2011-07-01

Full Text Available Abstract Background Monogynous mating systems with extremely low male mating rates have several independent evolutionary origins and are associated with drastic adaptations involving self-sacrifice, one-shot genitalia, genital damage, and termination of spermatogenesis immediately after maturation. The combination of such extreme traits likely restricts evolutionary potential perhaps up to the point of making low male mating rates irreversible and hence may constitute an evolutionary dead end. Here, we explore the case of a reversion to multiple mating from monogynous ancestry in golden orb-web spiders, Nephila senegalensis. Results Male multiple mating is regained by the loss of genital damage and sexual cannibalism but spermatogenesis is terminated with maturation, restricting males to a single loading of their secondary mating organs and a fixed supply of sperm. However, males re-use their mating organs and by experimentally mating males to many females, we show that the sperm supply is divided between copulations without reloading the pedipalps. Conclusion By portioning their precious sperm supply, males achieve an average mating rate of four females which effectively doubles the maximal mating rate of their ancestors. A heritage of one-shot genitalia does not completely restrict the potential to increase mating rates in Nephila although an upper limit is defined by the available sperm load. Future studies should now investigate how males use this potential in the field and identify selection pressures responsible for a reversal from monogynous to polygynous mating strategies.

Resolving the ambiguity: Making sense of intrinsic disorder when PDB structures disagree.

Science.gov (United States)

DeForte, Shelly; Uversky, Vladimir N

2016-03-01

Missing regions in X-ray crystal structures in the Protein Data Bank (PDB) have played a foundational role in the study of intrinsically disordered protein regions (IDPRs), especially in the development of in silico predictors of intrinsic disorder. However, a missing region is only a weak indication of intrinsic disorder, and this uncertainty is compounded by the presence of ambiguous regions, where more than one structure of the same protein sequence "disagrees" in terms of the presence or absence of missing residues. The question is this: are these ambiguous regions intrinsically disordered, or are they the result of static disorder that arises from experimental conditions, ensembles of structures, or domain wobbling? A novel way of looking at ambiguous regions in terms of the pattern between multiple PDB structures has been demonstrated. It was found that the propensity for intrinsic disorder increases as the level of ambiguity decreases. However, it is also shown that ambiguity is more likely to occur as the protein region is placed within different environmental conditions, and even the most ambiguous regions as a set display compositional bias that suggests flexibility. The results suggested that ambiguity is a natural result for many IDPRs crystallized under different conditions and that static disorder and wobbling domains are relatively rare. Instead, it is more likely that ambiguity arises because many of these regions were conditionally or partially disordered. © 2016 The Protein Society.

The ambiguity of simplicity in quantum and classical simulation

International Nuclear Information System (INIS)

Aghamohammadi, Cina; Mahoney, John R.; Crutchfield, James P.

2017-01-01

Highlights: • Simplicity depends on whether a system is represented classically or quantally. • We demonstrate that simplicity is unavoidably ambiguous. • Relative simplicity changes order moving between classical and quantum descriptions. • Ambiguity of simplicity bears directly on model selection. - Abstract: A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the “elegance” of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

Chains of phase-shift ambiguities in elastic spin-0-spin-1/2 scattering

International Nuclear Information System (INIS)

Berends, F.A.; Reisen, J.C.J.M. van

1977-01-01

It is shown, that a previously constructed phase-shift ambiguity for an arbitrary number, 2L + 1, of partial waves can be connected to L - 1 other ambiguities. The two sets of phase shifts defined by the chain of ambiguities become equal (modulo π) at the endpoints of the chain, but in general not at the endpoints of the ambiguities. Also other examples of such chains are given. (Auth.)

Origin of the Gribov ambiguity

International Nuclear Information System (INIS)

Takahashi, Y.; Kobayashi, M.

1978-01-01

It is pointed out that the Gribov ambiguity for the non-abelian transverse gauge field has the same origin as the Johnson-Sudarshan problem for the spin-3/2 field as well as the propagation problem discovered by Velo and Zwanziger. (Auth.)

The known unknowns: neural representation of second-order uncertainty, and ambiguity

Science.gov (United States)

Bach, Dominik R.; Hulme, Oliver; Penny, William D.; Dolan, Raymond J.

2011-01-01

Predictions provided by action-outcome probabilities entail a degree of (first-order) uncertainty. However, these probabilities themselves can be imprecise and embody second-order uncertainty. Tracking second-order uncertainty is important for optimal decision making and reinforcement learning. Previous functional magnetic resonance imaging investigations of second-order uncertainty in humans have drawn on an economic concept of ambiguity, where action-outcome associations in a gamble are either known (unambiguous) or completely unknown (ambiguous). Here, we relaxed the constraints associated with a purely categorical concept of ambiguity and varied the second-order uncertainty of gambles continuously, quantified as entropy over second-order probabilities. We show that second-order uncertainty influences decisions in a pessimistic way by biasing second-order probabilities, and that second-order uncertainty is negatively correlated with posterior cingulate cortex activity. The category of ambiguous (compared to non-ambiguous) gambles also biased choice in a similar direction, but was associated with distinct activation of a posterior parietal cortical area; an activation that we show reflects a different computational mechanism. Our findings indicate that behavioural and neural responses to second-order uncertainty are distinct from those associated with ambiguity and may call for a reappraisal of previous data. PMID:21451019

Top-Down Influence in Young Children's Linguistic Ambiguity Resolution

Science.gov (United States)

Rabagliati, Hugh; Pylkkanen, Liina; Marcus, Gary F.

2013-01-01

Language is rife with ambiguity. Do children and adults meet this challenge in similar ways? Recent work suggests that while adults resolve syntactic ambiguities by integrating a variety of cues, children are less sensitive to top-down evidence. We test whether this top-down insensitivity is specific to syntax or a general feature of children's…

Degenerate gauge conditions, generalized Gribov's ambiguity and BRST symmetry

International Nuclear Information System (INIS)

Fabbrichesi, M.E.

1987-01-01

The BFS-BRST approach to gauge theories is considered. It is argued that the BRST-invariant boundary conditions ordinarily used do not maintain the necessary degeneracy in the gauge fixing. As a by-product of this discussion, the existence of a generalized Gribov-like ambiguity is suggested. This ambiguity is however shown to be just a particular BRST transformation

Experience with intersex surgery at Bingham University Teaching ...

African Journals Online (AJOL)

Case Report A 15 – year- old boy presented with ambiguous genitalia and breast enlargement. History revealed that he was born with a small penis and lack of testes on one side. He gave a history of monthly menses and having to urinate while standing. He was assigned a male gender, even though he developed large ...

Comparing the ambiguity reduction abilities of probabilistic context-free grammars

NARCIS (Netherlands)

Infante-Lopez, G.G.; de Rijke, M.

2004-01-01

We present a measure for evaluating Probabilistic Context Free Grammars (PCFG) based on their ambiguity resolution capabilities.Probabilities in a PCFG can be seen as a filtering mechanism: For an ambiguous sentence, the trees bearing maximum probability aresingle out, while all others are

A study of potential sources of linguistic ambiguity in written work instructions.

Energy Technology Data Exchange (ETDEWEB)

Matzen, Laura E.

2009-11-01

This report describes the results of a small experimental study that investigated potential sources of ambiguity in written work instructions (WIs). The English language can be highly ambiguous because words with different meanings can share the same spelling. Previous studies in the nuclear weapons complex have shown that ambiguous WIs can lead to human error, which is a major cause for concern. To study possible sources of ambiguity in WIs, we determined which of the recommended action verbs in the DOE and BWXT writer's manuals have numerous meanings to their intended audience, making them potentially ambiguous. We used cognitive psychology techniques to conduct a survey in which technicians who use WIs in their jobs indicated the first meaning that came to mind for each of the words. Although the findings of this study are limited by the small number of respondents, we identified words that had many different meanings even within this limited sample. WI writers should pay particular attention to these words and to their most frequent meanings so that they can avoid ambiguity in their writing.

Optimal observables and phase-space ambiguities

International Nuclear Information System (INIS)

Nachtmann, O.; Nagel, F.

2005-01-01

Optimal observables are known to lead to minimal statistical errors on parameters for a given normalised event distribution of a physics reaction. Thereby all statistical correlations are taken into account. Therefore, on the one hand they are a useful tool to extract values on a set of parameters from measured data. On the other hand one can calculate the minimal constraints on these parameters achievable by any data-analysis method for the specific reaction. In case the final states can be reconstructed without ambiguities optimal observables have a particularly simple form. We give explicit formulae for the optimal observables for generic reactions in case of ambiguities in the reconstruction of the final state and for general parameterisation of the final-state phase space. (orig.)

Ambiguity among Managers in Small-Scale Enterprises: How to Handle Business and Workplace Health Management

Directory of Open Access Journals (Sweden)

Stig Vinberg

2017-11-01

Full Text Available Despite extensive research on health in working life, few studies focus on this issue from the perspective of managers in small-scale enterprises (SSEs. To gain deeper knowledge of managers’ perceptions and strategies for dealing with workplace health management, 13 Norwegian and Swedish SSE managers were interviewed after participating in a workplace health development project. The methodical approach was based on Grounded Theory with a constructivist orientation. The main theme that emerged was ‘ambiguity in workplace health management and maintaining the business’, which was related to the categories ‘internal workplace settings’, ‘workplace surroundings’, and ‘leadership strategies’. The managers experienced ambiguity due to internal and external demands. These requirements were linked to the core challenges in dealing with multitasking leadership, financial decision-making, labour legislation, staff development and maintaining business. However, the managers developed new skills and competence and thereby a more reflexive approach and readiness to create a health-promoting workplace from being part of a development project. The implications are that managers in SSEs need to exchange experiences and discuss workplace health issues with other managers in networks. It is also important that occupational health services and social and welfare organizations use tailor-made models and strategies for supporting SSEs.

On ambiguities in the exponentiation of large QCD perturbative corrections

International Nuclear Information System (INIS)

Chyla, Jiri

1986-01-01

Ambiguities and some practical questions connected with the exponentiation of higher-order QCD perturbative corrections are discussed for the case of deep inelastic lepton-hadron scattering in the non-singlet channel. The importance of still higher-order calculations for resolving these ambiguities is stressed. (author)

Ambiguities of the natural gauge in Yang-Mills theories

International Nuclear Information System (INIS)

Lazarides, G.

1978-01-01

We study the ambiguities of the natural gauge condition for the Euclidean SU(2) Yang-Mills theory in four dimensions. Then, we show that, in the stationary-phase approximation, these ambiguities do not affect the contribution of the sector with Pontryagin index q = 1 to the correlation functions of gauge-invariant operators. They affect only the higher-order corrections to this contribution

Clock ambiguity and the emergence of physical laws

International Nuclear Information System (INIS)

Albrecht, Andreas; Iglesias, Alberto

2008-01-01

The process of identifying a time variable in time-reparameterization invariant theories results in great ambiguities about the actual laws of physics described by a given theory. A theory set up to describe one set of physical laws can equally well be interpreted as describing any other laws of physics by making a different choice of time variable or clock. In this article we demonstrate how this 'clock ambiguity' arises and then discuss how one might still hope to extract specific predictions about the laws of physics even when the clock ambiguity is present. We argue that a requirement of quasiseparability should play a critical role in such an analysis. As a step in this direction, we compare the Hamiltonian of a local quantum field theory with a completely random Hamiltonian. We find that any random Hamiltonian (constructed in a sufficiently large space) can yield a 'good enough' approximation to a local field theory. Based on this result we argue that theories that suffer from the clock ambiguity may in the end provide a viable fundamental framework for physics in which locality can be seen as a strongly favored (or predicted) emergent behavior. We also speculate on how other key aspects of known physics such as gauge symmetries and Poincare invariance might be predicted to emerge in this framework.

DIFFERENCES OF THE ROLE AMBIGUITY IN OFFENSE RESPONSIBILITIES OF TEAM SPORTS

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Karamousalidis, G.

2009-10-01

Full Text Available The purpose of this research was to investigate the differences of the role ambiguity in offense responsibilitiesfor athletes of team sports. As sample were used 421 athletes of basketball (n=125, handball (n=106, volleyball(n=78 and soccer (n=112. We used the role ambiguity questionnaire (Role Ambiguity Scale, Beauchamp et al.,2002 and referred to the athletes’ responsibilities in offense.The correlations of items were high and ranged from .57 to .75, p <.01 whereas from the one way analysis (oneway, Anova appeared some statistically serious differences in one factor of role ambiguity (ambiguity inrelation to the scope of responsibilities in offense, F (3,415 = 4,416, p <.005. The volleyball and the handballathletes had more well defined roles regardless the scope of their responsibilities in offense, in relation to thoseof soccer. On the whole we come to the conclusion that among team sports there are not any differences in roleambiguity in offense responsibilities, except in one factor. More researches are necessary in connection to othervariables.

Ambiguity Tolerance and Perceptual Learning Styles of Chinese EFL Learners

Science.gov (United States)

Li, Haishan; He, Qingshun

2016-01-01

Ambiguity tolerance and perceptual learning styles are the two influential elements showing individual differences in EFL learning. This research is intended to explore the relationship between Chinese EFL learners' ambiguity tolerance and their preferred perceptual learning styles. The findings include (1) the learners are sensitive to English…

Tracking Down the Origins of Ambiguity in Context-Free Grammars

NARCIS (Netherlands)

H.J.S. Basten (Bas)

2010-01-01

htmlabstractContext-free grammars are widely used but still hindered by ambiguity. This stresses the need for detailed detection methods that point out the sources of ambiguity in a grammar. In this paper we show how the approximative Noncanonical Unambiguity Test by Schmitz can be extended to

Ambiguity: A new way of thinking about responses to climate change.

Science.gov (United States)

Fleming, A; Howden, S M

2016-11-15

Diversity, interdisciplinarity and transdisciplinarity are now recognized as vital to tackling wicked problems such as those presented by a changing climate (Nature editorial 2015, Ledford 2015; Dick et al., 2016). Including diverse disciplines in science projects enables a range of different views which often facilitate the creation of innovative solutions. Supporting multiple views and options requires a different way of working beyond traditional reductionist approaches to science, communication and decision-making. To embrace diversity in scientific project teams in order to tackle complex, integrated and urgent issues but to expect singular and linear pathways forward is paradoxical. Much has been written about the need for the scientific community to embrace uncertainty (e.g. Popper, Lempert & Bankes 2005; Lempert et al., 2004; Nelson, Howden & Hayman 2013; Bammer & Smithson 2008). We argue that this in itself will not suffice, and that there is also a need to embrace ambiguity in certain situations. Thus, in this article we explore: (1) what ambiguity is, including the benefits it can offer to climate adaptation in particular, using existing approaches to ambiguity in the arts and humanities as examples (2), we discuss practical meanings of ambiguity in relation to climate change, (3) we propose possible next steps for bringing ambiguity into interdisciplinary practice, and (4) we identify some challenges and necessary preconditions to successfully and appropriately embracing ambiguity. Copyright © 2016 Elsevier B.V. All rights reserved.

The ambiguity of simplicity in quantum and classical simulation

Energy Technology Data Exchange (ETDEWEB)

Aghamohammadi, Cina, E-mail: caghamohammadi@ucdavis.edu; Mahoney, John R., E-mail: jrmahoney@ucdavis.edu; Crutchfield, James P., E-mail: chaos@ucdavis.edu

2017-04-11

Highlights: • Simplicity depends on whether a system is represented classically or quantally. • We demonstrate that simplicity is unavoidably ambiguous. • Relative simplicity changes order moving between classical and quantum descriptions. • Ambiguity of simplicity bears directly on model selection. - Abstract: A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the “elegance” of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language.

Science.gov (United States)

Lu, Yao; Wu, Junjie; Dunlap, Susan; Chen, Baoguo

2017-01-01

Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2) learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese-English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning) and half were ambiguous (had two semantically unrelated meanings learned in sequence). Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language

Directory of Open Access Journals (Sweden)

Baoguo Chen

2017-04-01

Full Text Available Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2 learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese–English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning and half were ambiguous (had two semantically unrelated meanings learned in sequence. Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

Phase-ambiguity resolution for QPSK modulation systems. Part 1: A review

Science.gov (United States)

Nguyen, Tien Manh

1989-01-01

Part 1 reviews the current phase-ambiguity resolution techniques for QPSK coherent modulation systems. Here, those known and published methods of resolving phase ambiguity for QPSK with and without Forward-Error-Correcting (FEC) are discussed. The necessary background is provided for a complete understanding of the second part where a new technique will be discussed. An appropriate technique to the Consultative Committee for Space Data Systems (CCSDS) is recommended for consideration in future standards on phase-ambiguity resolution for QPSK coherent modulation systems.

Ambiguous taxa: Effects on the characterization and interpretation of invertebrate assemblages

Science.gov (United States)

Cuffney, T.F.; Bilger, Michael D.; Haigler, A.M.

2007-01-01

Damaged and immature specimens often result in macroinvertebrate data that contain ambiguous parent-child pairs (i.e., abundances associated with multiple related levels of the taxonomic hierarchy such as Baetis pluto and the associated ambiguous parent Baetis sp.). The choice of method used to resolve ambiguous parent-child pairs may have a very large effect on the characterization of invertebrate assemblages and the interpretation of responses to environmental change because very large proportions of taxa richness (73-78%) and abundance (79-91%) can be associated with ambiguous parents. To address this issue, we examined 16 variations of 4 basic methods for resolving ambiguous taxa: RPKC (remove parent, keep child), MCWP (merge child with parent), RPMC (remove parent or merge child with parent depending on their abundances), and DPAC (distribute parents among children). The choice of method strongly affected assemblage structure, assemblage characteristics (e.g., metrics), and the ability to detect responses along environmental (urbanization) gradients. All methods except MCWP produced acceptable results when used consistently within a study. However, the assemblage characteristics (e.g., values of assemblage metrics) differed widely depending on the method used, and data should not be combined unless the methods used to resolve ambiguous taxa are well documented and are known to be comparable. The suitability of the methods was evaluated and compared on the basis of 13 criteria that considered conservation of taxa richness and abundance, consistency among samples, methods, and studies, and effects on the interpretation of the data. Methods RPMC and DPAC had the highest suitability scores regardless of whether ambiguous taxa were resolved for each sample separately or for a group of samples. Method MCWP gave consistently poor results. Methods MCWP and DPAC approximate the use of family-level identifications and operational taxonomic units (OTU), respectively. Our

Estimating Ambiguity Preferences and Perceptions in Multiple Prior Models: Evidence from the Field

NARCIS (Netherlands)

S.G. Dimmock (Stephen); R.R.P. Kouwenberg (Roy); O.S. Mitchell (Olivia); K. Peijnenburg (Kim)

2015-01-01

markdownabstractWe develop a tractable method to estimate multiple prior models of decision-making under ambiguity. In a representative sample of the U.S. population, we measure ambiguity attitudes in the gain and loss domains. We find that ambiguity aversion is common for uncertain events of

Lexical ambiguity resolution during sentence processing in Parkinson's disease: An event-related potential study.

Directory of Open Access Journals (Sweden)

Anthony J Angwin

Full Text Available Event-related potentials (ERPs were recorded to investigate lexical ambiguity resolution during sentence processing in 16 people with Parkinson's disease (PD and 16 healthy controls. Sentences were presented word-by-word on computer screen, and participants were required to decide if a subsequent target word was related to the meaning of the sentence. The task consisted of related, unrelated and ambiguous trials. For the ambiguous trials, the sentence ended with an ambiguous word and the target was related to one of the meanings of that word, but not the one captured by the sentence context (e.g., 'He dug with the spade', Target 'ACE'. Both groups demonstrated slower reaction times and lower accuracy for the ambiguous condition relative to the unrelated condition, however accuracy was impacted by the ambiguous condition to a larger extent in the PD group. These results suggested that PD patients experience increased difficulties with contextual ambiguity resolution. The ERP results did not reflect increased ambiguity resolution difficulties in PD, as a similar N400 effect was evident for the unrelated and ambiguous condition in both groups. However, the magnitude of the N400 for these conditions was correlated with a measure of inhibition in the PD group, but not the control group. The ERP results suggest that semantic processing may be more compromised in PD patients with increased response inhibition deficits.

Theory-Based Evaluation Meets Ambiguity: The Role of Janus Variables

Science.gov (United States)

Dahler-Larsen, Peter

2018-01-01

As theory-based evaluation (TBE) engages in situations where multiple stakeholders help develop complex program theory about dynamic phenomena in politically contested settings, it becomes difficult to develop and use program theory without ambiguity. The purpose of this article is to explore ambiguity as a fruitful perspective that helps TBE face…

Identification and Definition of Lexically Ambiguous Words in Statistics by Tutors and Students

Science.gov (United States)

Richardson, Alice M.; Dunn, Peter K.; Hutchins, Rene

2013-01-01

Lexical ambiguity arises when a word from everyday English is used differently in a particular discipline, such as statistics. This paper reports on a project that begins by identifying tutors' perceptions of words that are potentially lexically ambiguous to students, in two different ways. Students' definitions of nine lexically ambiguous words…

Spectral Ambiguity of Allan Variance

Science.gov (United States)

Greenhall, C. A.

1996-01-01

We study the extent to which knowledge of Allan variance and other finite-difference variances determines the spectrum of a random process. The variance of first differences is known to determine the spectrum. We show that, in general, the Allan variance does not. A complete description of the ambiguity is given.

Ambiguity in Speaking Chemistry and Other STEM Content: Educational Implications

Science.gov (United States)

Isaacson, Mick D.; Michaels, Michelle

2015-01-01

Ambiguity in speech is a possible barrier to the acquisition of knowledge for students who have print disabilities (such as blindness, visual impairments, and some specific learning disabilities) and rely on auditory input for learning. Chemistry appears to have considerable potential for being spoken ambiguously and may be a barrier to accessing…

Electrodermal responses during appetitive conditioning are sensitive to contingency instruction ambiguity.

Science.gov (United States)

van den Akker, Karolien; Nederkoorn, Chantal; Jansen, Anita

2017-08-01

Studies on human appetitive conditioning using food rewards can benefit from including psychophysiological outcome measures. The present study tested whether the skin conductance response can function as a measure of differential responding in an appetitive conditioning paradigm including an acquisition and extinction phase, and examined which time window during a trial is most sensitive to conditioning effects. As a secondary aim, the effects of ambiguous vs. non-ambiguous contingency instructions on conditioned responses (skin conductance responses, US expectancies, chocolate desires, and CS evaluations) were assessed. Results indicated differential skin conductance responses in an anticipatory time window and during unexpected omission of the US in early extinction. Interestingly however, anticipatory responses were only found for participants who received ambiguous contingency instructions - possibly indicating a call for additional processing resources in response to the ambiguous CS+. Further, ambiguous instructions slowed the extinction of US expectancies but did not influence chocolate desires and CS evaluations. It is concluded that skin conductance can function as a sensitive measure of differential responding in appetitive conditioning, though its sensitivity might depend on the specific task context. Copyright © 2017 Elsevier B.V. All rights reserved.

Logic without unique readability - a study of semantic and syntactic ambiguity

DEFF Research Database (Denmark)

Bentzen, Martin Mose

One of the main reasons for introducing a formal language is to remove ambiguity, the possibility of assigning several meanings to a linguistic expression. Typically, this is achieved through ensuring unique readability of formulas by using brackets (or another convention, such as Polish notation...... not hold true universally. Whereas e.g. scope ambiguities in natural languages have been studied extensively, ambiguous formal languages have not been the focus of in depth research. Here, we lift the assumption of unique readability by omitting the brackets from propositional logic, making it possible...... to formally distinguish between syntactic and semantic ambiguity. A valuation then amounts to a semantic disambiguation, and rather than a unique valuation (truth value), there is a set of valuations corresponding to ways a formula could have been constructed. We show what happens to familiar concepts...

The real potential continuous ambiguity for 90 MeV Li ions

International Nuclear Information System (INIS)

Cook, J.; Barnwell, J.M.; Clarke, N.M.; Griffiths, R.J.

1980-01-01

The features of discrete and continuous ambiguities in the real phenomenological optical potential are clarified. The continuous ambiguity in the real potential for the scattering of 90 MeV 6 Li and 7 Li ions from 27 Al is investigated. For 6 Li the ambiguity is of Igo (Phys. Rev. Lett.; 1: 72 (1958) and Phys. Rev.; 115: 1665 (1959)) type but for 7 Li it is of Vrsup(n) = constant type. The implications of this are that 7 Li is less strongly absorbed than 6 Li. (author)

The impact of ambiguous economic news on uncertainty and consumer confidence

NARCIS (Netherlands)

Svensson, H.M.; Albæk, E.; van Dalen, A.; de Vreese, C.H.

Journalistic practice emphasizes both positive and negative aspects of news stories. Nevertheless, the effects of ambiguous news, which includes both positive and negative information, are under-investigated. This study examines how exposure to ambiguous economic news affects uncertainty and

When in doubt, seize the day? Security values, prosocial values, and proactivity under ambiguity.

Science.gov (United States)

Grant, Adam M; Rothbard, Nancy P

2013-09-01

Researchers have suggested that both ambiguity and values play important roles in shaping employees' proactive behaviors, but have not theoretically or empirically integrated these factors. Drawing on theories of situational strength and values, we propose that ambiguity constitutes a weak situation that strengthens the relationship between the content of employees' values and their proactivity. A field study of 204 employees and their direct supervisors in a water treatment plant provided support for this contingency perspective. Ambiguity moderated the relationship between employees' security and prosocial values and supervisor ratings of proactivity. Under high ambiguity, security values predicted lower proactivity, whereas prosocial values predicted higher proactivity. Under low ambiguity, values were not associated with proactivity. We replicated these findings in a laboratory experiment with 232 participants in which we measured proactivity objectively as initiative taken to correct errors: Participants with strong security values were less proactive, and participants with strong prosocial values were more proactive, but only when performance expectations were ambiguous. We discuss theoretical implications for research on proactivity, values, and ambiguity and uncertainty. PsycINFO Database Record (c) 2013 APA, all rights reserved

Elements of morphology: standard terminology for the external genitalia

NARCIS (Netherlands)

Hennekam, Raoul C. M.; Allanson, Judith E.; Biesecker, Leslie G.; Carey, John C.; Opitz, John M.; Vilain, Eric

2013-01-01

An international group of clinicians working in the field of dysmorphology has initiated the standardization of terms used to describe human morphology. The goals are to standardize these terms and reach consensus regarding their definitions. In this way, we will increase the utility of descriptions

Sadder but wiser : the effects of emotional states on ambiguity attitudes

NARCIS (Netherlands)

Baillon, A.; Koelinger, P.; Treffers, T.

“Many important decisions are made without precise information about the probabilities of the outcomes. In such situations, individual ambiguity attitudes influence decision making. The present study identifies emotions as a transient cause of ambiguity attitudes. We conducted two random-assignment,

Psychophsyiological reactivity during uncertainty and ambiguity processing in high and low worriers.

Science.gov (United States)

Kirschner, Hans; Hilbert, Kevin; Hoyer, Jana; Lueken, Ulrike; Beesdo-Baum, Katja

2016-03-01

Intolerance of uncertainty (IU) has been linked to Generalized Anxiety Disorder (GAD), but studies experimentally manipulating uncertainty have mostly failed to find differences between GAD patients and controls, possible due to a lack of distinction between uncertainty and ambiguity. This study therefore investigated reactivity to ambiguity in addition to uncertainty in high worriers (HW) and low worriers (LW). We hypothesized an interpretation bias between the groups during ambiguity tasks, while uncertainty would facilitate threat processing of subsequent aversive stimuli. HW (N = 23) and LW (N = 23) completed a paradigm comprising the anticipation and perception of pictures with dangerous, safe, or ambiguous content. Anticipatory cues were certain (always correct information about the following picture) or uncertain (no information). Subjective ratings, reaction times and skin conductance responses (SCRs) were recorded. HW rated particularly ambiguous pictures as more aversive and showed longer reaction times to all picture conditions compared to LW. SCRs were also larger in HW compared to LW, particularly during uncertain but also safe anticipation. No group differences were observed during perception of stimuli. All participants were female. HW was used as subclinical phenotype of GAD. Intolerance of ambiguity seems to be related to individual differences in worry and possibly to the development of GAD. Threat-related interpretations differentiating HW and LW occurred particularly for ambiguous pictures but were not accompanied by increased autonomic arousal during the picture viewing. This disparity between subjective rating and arousal may be the result of worrying in response to intolerance of uncertainty, restraining physiological responses. Copyright © 2015 Elsevier Ltd. All rights reserved.

A mixture approach to vagueness and ambiguity.

Directory of Open Access Journals (Sweden)

Steven Verheyen

Full Text Available When asked to indicate which items from a set of candidates belong to a particular natural language category inter-individual differences occur: Individuals disagree which items should be considered category members. The premise of this paper is that these inter-individual differences in semantic categorization reflect both ambiguity and vagueness. Categorization differences are said to be due to ambiguity when individuals employ different criteria for categorization. For instance, individuals may disagree whether hiking or darts is the better example of sports because they emphasize respectively whether an activity is strenuous and whether rules apply. Categorization differences are said to be due to vagueness when individuals employ different cut-offs for separating members from non-members. For instance, the decision to include hiking in the sports category or not, may hinge on how strenuous different individuals require sports to be. This claim is supported by the application of a mixture model to categorization data for eight natural language categories. The mixture model can identify latent groups of categorizers who regard different items likely category members (i.e., ambiguity with categorizers within each of the groups differing in their propensity to provide membership responses (i.e., vagueness. The identified subgroups are shown to emphasize different sets of category attributes when making their categorization decisions.

POSTTRAUMATIC STRESS SYMPTOMS AND AVERSION TO AMBIGUOUS LOSSES IN COMBAT VETERANS.

Science.gov (United States)

Ruderman, Lital; Ehrlich, Daniel B; Roy, Alicia; Pietrzak, Robert H; Harpaz-Rotem, Ilan; Levy, Ifat

2016-07-01

Psychiatric symptoms typically cut across traditional diagnostic categories. In order to devise individually tailored treatments, there is a need to identify the basic mechanisms that underlie these symptoms. Behavioral economics provides a framework for studying these mechanisms at the behavioral level. Here, we utilized this framework to examine a widely ignored aspect of trauma-related symptomatology-individual uncertainty attitudes-in combat veterans with and without posttraumatic stress disorder (PTSD). Fifty-seven combat veterans, including 30 with PTSD and 27 without PTSD, completed a risk and ambiguity decision-making task that characterizes individual uncertainty attitudes, distinguishing between attitudes toward uncertain outcomes with known ("risk") and unknown ("ambiguity") probabilities, and between attitudes toward uncertain gains and uncertain losses. Participants' choices were used to estimate risk and ambiguity attitudes in the gain and loss domains. Veterans with PTSD were more averse to ambiguity, but not risk, compared to veterans without PTSD, when making choices between possible losses, but not gains. The degree of aversion was associated with anxious arousal (e.g., hypervigilance) symptoms, as well as with the degree of combat exposure. Moreover, ambiguity attitudes fully mediated the association between combat exposure and anxious arousal symptoms. These results provide a foundation for prospective studies of the causal association between ambiguity attitudes and trauma-related symptoms, as well as etiologic studies of the neural underpinnings of these behavioral outcomes. More generally, these results demonstrate the potential of neuroeconomic and behavioral economic techniques for devising objective and incentive-compatible diagnostic tools, and investigating the etiology of psychiatric disorders. © 2016 Wiley Periodicals, Inc.

Do you like Arcimboldo's? Esthetic appreciation modulates brain activity in solving perceptual ambiguity.

Science.gov (United States)

Boccia, M; Nemmi, F; Tizzani, E; Guariglia, C; Ferlazzo, F; Galati, G; Giannini, A M

2015-02-01

Esthetic experience is a unique, affectively colored, self-transcending subject-object relationship in which cognitive processing is felt to flow differently than during everyday experiences. Notwithstanding previous multidisciplinary investigations, how esthetic experience modulates perception is still obscure. We used Arcimboldo's ambiguous portraits to assess how the esthetic context organizes ambiguous percepts. The study was carried out using functional magnetic resonance imaging (fMRI) in healthy young volunteers (mean age 25.45; S.D. 4.51; 9 females), during both an explicit esthetic judgment task and an artwork/non-artwork classification task. We show that a distinct neural mechanism in the fusiform gyrus contributes to the esthetic experience of ambiguous portraits, according to the valence of the esthetic experience. Ambiguous artworks eliciting a negative esthetic experience lead to more pronounced activation of the fusiform face areas than ambiguous artworks eliciting a positive esthetic experience. We also found an interaction between task and ambiguity in the right superior parietal lobule. Taken together, our results demonstrate that a neural mechanism in the content-dependent brain regions of face processing underlies the esthetic experience of ambiguous portraits. Furthermore, they suggest that esthetic experience interacts with perceptual qualities of stimuli in the right superior parietal lobe, supporting the idea that esthetic experience arises from the interaction between top-down orienting of attention and bottom-up perceptual facilitation. Copyright © 2014 Elsevier B.V. All rights reserved.

Wind scatterometry with improved ambiguity selection and rain modeling

Science.gov (United States)

Draper, David Willis

Although generally accurate, the quality of SeaWinds on QuikSCAT scatterometer ocean vector winds is compromised by certain natural phenomena and retrieval algorithm limitations. This dissertation addresses three main contributors to scatterometer estimate error: poor ambiguity selection, estimate uncertainty at low wind speeds, and rain corruption. A quality assurance (QA) analysis performed on SeaWinds data suggests that about 5% of SeaWinds data contain ambiguity selection errors and that scatterometer estimation error is correlated with low wind speeds and rain events. Ambiguity selection errors are partly due to the "nudging" step (initialization from outside data). A sophisticated new non-nudging ambiguity selection approach produces generally more consistent wind than the nudging method in moderate wind conditions. The non-nudging method selects 93% of the same ambiguities as the nudged data, validating both techniques, and indicating that ambiguity selection can be accomplished without nudging. Variability at low wind speeds is analyzed using tower-mounted scatterometer data. According to theory, below a threshold wind speed, the wind fails to generate the surface roughness necessary for wind measurement. A simple analysis suggests the existence of the threshold in much of the tower-mounted scatterometer data. However, the backscatter does not "go to zero" beneath the threshold in an uncontrolled environment as theory suggests, but rather has a mean drop and higher variability below the threshold. Rain is the largest weather-related contributor to scatterometer error, affecting approximately 4% to 10% of SeaWinds data. A simple model formed via comparison of co-located TRMM PR and SeaWinds measurements characterizes the average effect of rain on SeaWinds backscatter. The model is generally accurate to within 3 dB over the tropics. The rain/wind backscatter model is used to simultaneously retrieve wind and rain from SeaWinds measurements. The simultaneous

Ambiguity Resolution for Phase-Based 3-D Source Localization under Fixed Uniform Circular Array.

Science.gov (United States)

Chen, Xin; Liu, Zhen; Wei, Xizhang

2017-05-11

Under fixed uniform circular array (UCA), 3-D parameter estimation of a source whose half-wavelength is smaller than the array aperture would suffer from a serious phase ambiguity problem, which also appears in a recently proposed phase-based algorithm. In this paper, by using the centro-symmetry of UCA with an even number of sensors, the source's angles and range can be decoupled and a novel algorithm named subarray grouping and ambiguity searching (SGAS) is addressed to resolve angle ambiguity. In the SGAS algorithm, each subarray formed by two couples of centro-symmetry sensors can obtain a batch of results under different ambiguities, and by searching the nearest value among subarrays, which is always corresponding to correct ambiguity, rough angle estimation with no ambiguity is realized. Then, the unambiguous angles are employed to resolve phase ambiguity in a phase-based 3-D parameter estimation algorithm, and the source's range, as well as more precise angles, can be achieved. Moreover, to improve the practical performance of SGAS, the optimal structure of subarrays and subarray selection criteria are further investigated. Simulation results demonstrate the satisfying performance of the proposed method in 3-D source localization.

Dispositional sources of sanction perceptions: Emotionality, cognitive style, intolerance of ambiguity, and self-efficacy.

Science.gov (United States)

Pickett, Justin T; Bushway, Shawn D

2015-12-01

This study contributes to efforts to identify the sources of arrest risk perceptions and ambiguity (or lack of confidence) in such perceptions. Drawing on dual-process theories of reasoning, we argue that arrest risk perceptions often represent intuitive judgments that are influenced by cognitive heuristics and dispositional attributes. Multivariate regression models are estimated with data from 3 national surveys to test 6 hypotheses about the relationships between specific dispositional attributes and perceived arrest risk and ambiguity. We find evidence that dispositional positive affect and intolerance of ambiguity are both positively related to perceived arrest risk, and are also both negatively related to ambiguity. We also find evidence that cognitive reflection and general self-efficacy are, respectively, positively and negatively associated with ambiguity. Mixed evidence emerges about whether cognitive reflection is related to risk perceptions, and about whether either dispositional negative affect or thoughtfully reflective decision making correlate with ambiguity. Taken together, the results provide partial support for each of our hypotheses, and suggest that dispositional attributes are important sources of perceptions of arrest risk as well as of ambiguity in such perceptions. (c) 2015 APA, all rights reserved).

HIPERPLASIA ADRENAL KONGENITAL (HAK KLASIK SIMPLE VIRILIZING PADA ANAK UMUR 3 TAHUN

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Alice Indradjaja

2015-01-01

Full Text Available Hiperplasia adrenal kongenital merupakan salah satu dari kelompok kelainan genetik akibat defisiensi enzim yang diperlukan untuk biosintesis steroid di korteks kelenjar adrenal. Bentuk kelainan hiperplasia adrenal kongenital yang tersering adalah defisiensi enzim 21-hidroksilase (21OHD hingga mencapai 90% kasus. Kelainan utama pada pasien dengan defisiensi enzim 21-hidroksilase adalah kegagalan sintesis kortisol secara adekuat. Defisiensi 21-hidroksilase klasik tipe virilisasi sederhana menyebabkan genitalia ambigu pada bayi perempuan. Dilaporkan sebuah kasus hiperplasia adrenal kongenital klasik tipe virilisasi sederhana pada anak perempuan usia tiga tahun. Pasien dirujuk ke Poliklinik anak RSUP Sanglah Denpasar dengan keluhan utama pembesaran dan pemanjangan klitoris yang progresif disertai tumbuhnya bulu pubis.  Pasien lahir dengan genitalia ambigu. Pasien didiagnosis defisiensi 21-hidroksilase berdasarkan hasil pemeriksaan kadar progesteron 17-OH >1.200ng/dl dan pemeriksaan fisik didapatkan prader derajat III. Pada pemeriksaan usia tulang menunjukkan usia tulang yang melebihi umurnya, USG abdomen dalam batas normal dengan hasil analisis kromosom 46,XX. Pasien tidak pernah mengalami krisis adrenal selama 3 tahun dan menjalani tindakan pembedahan pada usia 3 tahun. Keluarga pasien diberikan konseling, dilakukan monitor  berkala pada pasien dan terapi hidrokortison. Prognosis pada pasien ini baik. [MEDICINA 2014;45:58-64].

Motion discrimination under uncertainty and ambiguity.

NARCIS (Netherlands)

Kalisvaart, J.P.; Klaver, I.; Goossens, J.

2011-01-01

Speed and accuracy of visual motion discrimination depend systematically on motion strength. This behavior is traditionally explained by diffusion models that assume accumulation of sensory evidence over time to a decision bound. However, how does the brain decide when sensory evidence is ambiguous,

A New Block Processing Algorithm of LLL for Fast High-dimension Ambiguity Resolution

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LIU Wanke

2016-02-01

Full Text Available Due to high dimension and precision for the ambiguity vector under GNSS observations of multi-frequency and multi-system, a major problem to limit computational efficiency of ambiguity resolution is the longer reduction time when using conventional LLL algorithm. To address this problem, it is proposed a new block processing algorithm of LLL by analyzing the relationship between the reduction time and the dimensions and precision of ambiguity. The new algorithm reduces the reduction time to improve computational efficiency of ambiguity resolution, which is based on block processing ambiguity variance-covariance matrix that decreased the dimensions of single reduction matrix. It is validated that the new algorithm with two groups of measured data. The results show that the computing efficiency of the new algorithm increased by 65.2% and 60.2% respectively compared with that of LLL algorithm when choosing a reasonable number of blocks.

Auditory motion capturing ambiguous visual motion

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Arjen eAlink

2012-01-01

Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

A Range Ambiguity Suppression Processing Method for Spaceborne SAR with Up and Down Chirp Modulation.

Science.gov (United States)

Wen, Xuejiao; Qiu, Xiaolan; Han, Bing; Ding, Chibiao; Lei, Bin; Chen, Qi

2018-05-07

Range ambiguity is one of the factors which affect the SAR image quality. Alternately transmitting up and down chirp modulation pulses is one of the methods used to suppress the range ambiguity. However, the defocusing range ambiguous signal can still hold the stronger backscattering intensity than the mainlobe imaging area in some case, which has a severe impact on visual effects and subsequent applications. In this paper, a novel hybrid range ambiguity suppression method for up and down chirp modulation is proposed. The method can obtain the ambiguity area image and reduce the ambiguity signal power appropriately, by applying pulse compression using a contrary modulation rate and CFAR detecting method. The effectiveness and correctness of the approach is demonstrated by processing the archive images acquired by Chinese Gaofen-3 SAR sensor in full-polarization mode.

Spreading the Clinical Window for Diagnosing Fetal-Onset Hypogonadism in Boys

Science.gov (United States)

Grinspon, Romina P.; Loreti, Nazareth; Braslavsky, Débora; Valeri, Clara; Schteingart, Helena; Ballerini, María Gabriela; Bedecarrás, Patricia; Ambao, Verónica; Gottlieb, Silvia; Ropelato, María Gabriela; Bergadá, Ignacio; Campo, Stella M.; Rey, Rodolfo A.

2014-01-01

In early fetal development, the testis secretes – independent of pituitary gonadotropins – androgens and anti-Müllerian hormone (AMH) that are essential for male sex differentiation. In the second half of fetal life, the hypothalamic–pituitary axis gains control of testicular hormone secretion. Follicle-stimulating hormone (FSH) controls Sertoli cell proliferation, responsible for testis volume increase and AMH and inhibin B secretion, whereas luteinizing hormone (LH) regulates Leydig cell androgen and INSL3 secretion, involved in the growth and trophism of male external genitalia and in testis descent. This differential regulation of testicular function between early and late fetal periods underlies the distinct clinical presentations of fetal-onset hypogonadism in the newborn male: primary hypogonadism results in ambiguous or female genitalia when early fetal-onset, whereas it becomes clinically undistinguishable from central hypogonadism when established later in fetal life. The assessment of the hypothalamic–pituitary–gonadal axis in male has classically relied on the measurement of gonadotropin and testosterone levels in serum. These hormone levels normally decline 3–6 months after birth, thus constraining the clinical evaluation window for diagnosing male hypogonadism. The advent of new markers of gonadal function has spread this clinical window beyond the first 6 months of life. In this review, we discuss the advantages and limitations of old and new markers used for the functional assessment of the hypothalamic–pituitary–testicular axis in boys suspected of fetal-onset hypogonadism. PMID:24847309

Spreading the clinical window for diagnosing fetal-onset hypogonadism in boys

Directory of Open Access Journals (Sweden)

Rodolfo eRey

2014-05-01

Full Text Available In early fetal development, the testis secretes –independently of pituitary gonadotropins– androgens and anti-Müllerian hormone (AMH which are essential for male sex differentiation. In the second half of fetal life, the hypothalamic-pituitary axis gains control of testicular hormone secretion. FSH controls Sertoli cell proliferation, responsible for testis volume increase and AMH and inhibin B secretion, whereas LH regulates Leydig cell androgen and INSL3 secretion, involved in the growth and trophism of male external genitalia and in testis descent. This differential regulation of testicular function between early and late fetal periods underlies the distinct clinical presentations of fetal-onset hypogonadism in the newborn male: primary hypogonadism results in ambiguous or female genitalia when early fetal-onset whereas it becomes clinically undistinguishable from central hypogonadism when established later in fetal life. The assessment of the hypothalamic-pituitary-gonadal axis in the male has classically relied on the measurement of gonadotropin and testosterone levels in serum. These hormone levels normally decline 3-6 months after birth, thus constraining the clinical evaluation window for diagnosing male hypogonadism. The advent of new markers of gonadal function has spread this clinical window beyond the first 6 months of life. In this review, we discuss the advantages and limitations of old and new markers used for the functional assessment of the hypothalamic-pituitary-testicular axis in boys suspected of fetal-onset hypogonadism.

More than visual literacy: art and the enhancement of tolerance for ambiguity and empathy.

Science.gov (United States)

Bentwich, Miriam Ethel; Gilbey, Peter

2017-11-10

Comfort with ambiguity, mostly associated with the acceptance of multiple meanings, is a core characteristic of successful clinicians. Yet past studies indicate that medical students and junior physicians feel uncomfortable with ambiguity. Visual Thinking Strategies (VTS) is a pedagogic approach involving discussions of art works and deciphering the different possible meanings entailed in them. However, the contribution of art to the possible enhancement of the tolerance for ambiguity among medical students has not yet been adequately investigated. We aimed to offer a novel perspective on the effect of art, as it is experienced through VTS, on medical students' tolerance of ambiguity and its possible relation to empathy. Quantitative method utilizing a short survey administered after an interactive VTS session conducted within mandatory medical humanities course for first-year medical students. The intervention consisted of a 90-min session in the form of a combined lecture and interactive discussions about art images. The VTS session and survey were filled by 67 students in two consecutive rounds of first-year students. 67% of the respondents thought that the intervention contributed to their acceptance of multiple possible meanings, 52% thought their visual observation ability was enhanced and 34% thought that their ability to feel the sufferings of other was being enhanced. Statistically significant moderate-to-high correlations were found between the contribution to ambiguity tolerance and contribution to empathy (0.528-0.744; p ≤ 0.01). Art may contribute especially to the development of medical students' tolerance of ambiguity, also related to the enhancement of empathy. The potential contribution of visual art works used in VTS to the enhancement of tolerance for ambiguity and empathy is explained based on relevant literature regarding the embeddedness of ambiguity within art works, coupled with reference to John Dewey's theory of learning. Given the

Social structure predicts genital morphology in African mole-rats.

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Marianne L Seney

2009-10-01

Full Text Available African mole-rats (Bathyergidae, Rodentia exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure.We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate.The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology.

Social structure predicts genital morphology in African mole-rats.

Science.gov (United States)

Seney, Marianne L; Kelly, Diane A; Goldman, Bruce D; Sumbera, Radim; Forger, Nancy G

2009-10-15

African mole-rats (Bathyergidae, Rodentia) exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals examined. We hypothesized that the lack of sex differences in naked mole-rats might be related to their unusual social structure. We compared the genitalia and perineal muscles in three African mole-rat species: the naked mole-rat, the solitary silvery mole-rat, and the Damaraland mole-rat, a species considered to be eusocial, but with less reproductive skew than naked mole-rats. Our findings support a relationship between social structure, mating system, and sexual differentiation. Naked mole-rats lack sex differences in genitalia and perineal morphology, silvery mole-rats exhibit sex differences, and Damaraland mole-rats are intermediate. The lack of sex differences in naked mole-rats is not an attribute of all African mole-rats, but appears to have evolved in relation to their unusual social structure and reproductive biology.

A Range Ambiguity Suppression Processing Method for Spaceborne SAR with Up and Down Chirp Modulation

Directory of Open Access Journals (Sweden)

Xuejiao Wen

2018-05-01

Full Text Available Range ambiguity is one of the factors which affect the SAR image quality. Alternately transmitting up and down chirp modulation pulses is one of the methods used to suppress the range ambiguity. However, the defocusing range ambiguous signal can still hold the stronger backscattering intensity than the mainlobe imaging area in some case, which has a severe impact on visual effects and subsequent applications. In this paper, a novel hybrid range ambiguity suppression method for up and down chirp modulation is proposed. The method can obtain the ambiguity area image and reduce the ambiguity signal power appropriately, by applying pulse compression using a contrary modulation rate and CFAR detecting method. The effectiveness and correctness of the approach is demonstrated by processing the archive images acquired by Chinese Gaofen-3 SAR sensor in full-polarization mode.

Is ambiguity tolerance malleable? Experimental evidence with potential implications for future research.

Science.gov (United States)

Endres, Megan L; Camp, Richaurd; Milner, Morgan

2015-01-01

We conducted two research studies to address the malleability of tolerance of ambiguity (TA) by manipulating situational ambiguity. Students participated in a semester-end assessment of their management skills (n = 306). In Study 1, students in low and moderate ambiguity conditions had significantly higher post-experiment TA, more positive change in self-efficacy, and marginally higher faculty ratings. In Study 2, a control group (n = 103) did not participate in the assessment and was established for comparison to the first study results. The Study 2 students reported TA significantly lower than Study 1 students in the low and moderate ambiguity conditions. The control group TA was not significantly different from that of the Study 1 high ambiguity condition. This further suggested TA's situational malleability, as those who had controlled access to structured information appeared to have increased their TA over that observed in the other two groups. These results suggest that TA may be malleable. We review the relevant literature, offer hypotheses, report our analyses and findings, and then propose future research, and potential prescriptive applications in such areas as management development, assessment, and decision-making.

Size doesn't really matter: ambiguity aversion in Ellsberg urns with few balls.

Science.gov (United States)

Pulford, Briony D; Colman, Andrew M

2008-01-01

When attempting to draw a ball of a specified color either from an urn containing 50 red balls and 50 black balls or from an urn containing an unknown ratio of 100 red and black balls, a majority of decision makers prefer the known-risk urn, and this ambiguity aversion effect violates expected utility theory. In an experimental investigation of the effect of urn size on ambiguity aversion, 149 participants showed similar levels of aversion when choosing from urns containing 2, 10, or 100 balls. The occurrence of a substantial and significant ambiguity aversion effect even in the smallest urn suggests that influential theoretical interpretations of ambiguity aversion may need to be reconsidered.

Inherent ambiguities in the determination of phase-shifts

International Nuclear Information System (INIS)

Atkinson, D.

1975-01-01

The observables in an elastic scattering process are unchanged if all the scattering amplitudes are multiplied by the same angle-dependent phase. The non-spin-flip and spin-flip amplitudes remain unchanged by the substitution: g(cos theta)→g(cos theta)exp[i phi(cos theta)] and h(cos theta)→h(cos theta)exp[i phi(cos theta)]. Unless some extra and hoc assumption is made, there is a continuum ambiguity, which has been explored some time ago, with specific models for the phase phi by members of the Birmingham group. In the ordinary quantum mechanics of scattering, one writes a wave-function asymptotically as psi(r - ) approximately esup(ikr costheta)+f(cos theta)esup(ikr)/r where f is the scattering amplitude. The ambiguity which is a change in the phase of the scattering amplitude, and thus of the scattered part of the wavefunction, but with no change of the first term in (the unscattered plane wave coming along the z-axis is discussed in detail. Preliminary results in the energy-range 1550-1750 MeV cm and their implications are given. Argand plots of ambiguities at various energies are presented. (K.B.)

Exploiting Lexical Ambiguity to Help Students Understand the Meaning of "Random"

Science.gov (United States)

Kaplan, Jennifer J.; Rogness, Neal T.; Fisher, Diane G.

2014-01-01

Words that are part of colloquial English but used differently in a technical domain may possess lexical ambiguity. The use of such words by instructors may inhibit student learning if incorrect connections are made by students between the technical and colloquial meanings. One fundamental word in statistics that has lexical ambiguity for students…

Aggregating imprecise or conflicting beliefs: An experimental investigation using modern ambiguity theories

NARCIS (Netherlands)

A. Baillon (Aurélien); L. Cabantous (Laure); P.P. Wakker (Peter)

2012-01-01

textabstractTwo experiments show that violations of expected utility due to ambiguity, found in general decision experiments, also affect belief aggregation. Hence we use modern ambiguity theories to analyze belief aggregation, thus obtaining more refined and empirically more valid results than

The skew ray ambiguity in the analysis of videokeratoscopic data.

Science.gov (United States)

Iskander, D Robert; Davis, Brett A; Collins, Michael J

2007-05-01

Skew ray ambiguity is present in most videokeratoscopic measurements when azimuthal components of the corneal curvature are not taken into account. There have been some reported studies based on theoretical predictions and measured test surfaces suggesting that skew ray ambiguity is significant for highly deformed corneas or decentered corneal measurements. However, the effect of skew ray ambiguity in ray tracing through videokeratoscopic data has not been studied in depth. We have evaluated the significance of the skew ray ambiguity and its effect on the analyzed corneal optics. This has been achieved by devising a procedure in which we compared the corneal wavefront aberrations estimated from 3D ray tracing with those determined from 2D (meridional based) estimates of the refractive power. The latter was possible due to recently developed concept of refractive Zernike power polynomials which links the refractive power domain with that of the wavefront. Simulated corneal surfaces as well as data from a range of corneas (from two different Placido disk-based videokeratoscopes) were used to find the limit at which the difference in estimated corneal wavefronts (or the corresponding refractive powers) would have clinical significance (e.g., equivalent to 0.125 D or more). The inclusion/exclusion of the skew ray in the analyses showed some differences in the results. However, the proposed procedure showed clinically significant differences only for highly deformed corneas and only for large corneal diameters. For the overwhelming majority of surfaces, the skew ray ambiguity is not a clinically significant issue in the analysis of the videokeratoscopic data indicating that the meridional processing such as that encountered in calculation of the refractive power maps is adequate.

The role of ambiguity and discrepancy in the early phases of innovation

DEFF Research Database (Denmark)

Laursen, Linda Nhu; Tollestrup, Christian H. T.

2015-01-01

Innovation literature mainly focuses on eliminating ambiguity and discrepancy from the early phases of innovation. This study questions this implicit assumption, as it may provide an oversimplified view on, how to attain proficiency. Instead of narrowly focusing on reducing ambiguity and discrepa...

More is not always better: coping with ambiguity in natural resources management

NARCIS (Netherlands)

Brugnach, M.; Dewulf, A.; Henriksen, H.J.; Keur, van der P.

2011-01-01

Coping with ambiguities in natural resources management has become unavoidable. Ambiguity is a distinct type of uncertainty that results from the simultaneous presence of multiple valid, and sometimes conflicting, ways of framing a problem. As such, it reflects discrepancies in meanings and

More is not always better: Coping with ambiguity in natural resources management

NARCIS (Netherlands)

Brugnach, Marcela Fabiana; De Wulf, A.; Henriksen, H.J.; van der Keur, P.

2011-01-01

Coping with ambiguities in natural resources management has become unavoidable. Ambiguity is a distinct type of uncertainty that results from the simultaneous presence of multiple valid, and sometimes conflicting, ways of framing a problem. As such, it reflects discrepancies in meanings and

Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

Science.gov (United States)

Wimmer, Marina C; Stirk, Steven; Hancock, Peter J B

2017-10-01

This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

Task Characteristics and Work Engagement: Exploring Effects of Role Ambiguity and ICT Presenteeism

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Sang-Hoon Lee

2017-10-01

Full Text Available In order to secure organizational sustainability in a rapidly changing environment, it is necessary to implement a decentralized and flexible work environment. In such work environments, normally individuals are provided with autonomy and independence in performing tasks, thus allowing them to further engage in their given work. This study investigated task antecedents of work engagement, and further explored the process of how task characteristics affect work engagement. It focused on examining the mediating effect of role ambiguity on the task characteristics-work engagement relationship and the moderating effect of information and communication technology (ICT presenteeism on the task characteristics–role ambiguity relationship through multiple regression analyses and a bootstrapping procedure on survey data collected from 202 South Korean employees. It found that task interdependence and autonomy were negatively associated with role ambiguity. Of the two task characteristics, only task interdependence had a negative relationship with role ambiguity, and this relationship was significantly moderated by ICT presenteeism such that the negative association between task interdependence and role ambiguity was more pronounced when ICT presenteeism was high than when it was low.

An adaptation study of internal and external features in facial representations.

Science.gov (United States)

Hills, Charlotte; Romano, Kali; Davies-Thompson, Jodie; Barton, Jason J S

2014-07-01

Prior work suggests that internal features contribute more than external features to face processing. Whether this asymmetry is also true of the mental representations of faces is not known. We used face adaptation to determine whether the internal and external features of faces contribute differently to the representation of facial identity, whether this was affected by familiarity, and whether the results differed if the features were presented in isolation or as part of a whole face. In a first experiment, subjects performed a study of identity adaptation for famous and novel faces, in which the adapting stimuli were whole faces, the internal features alone, or the external features alone. In a second experiment, the same faces were used, but the adapting internal and external features were superimposed on whole faces that were ambiguous to identity. The first experiment showed larger aftereffects for unfamiliar faces, and greater aftereffects from internal than from external features, and the latter was true for both familiar and unfamiliar faces. When internal and external features were presented in a whole-face context in the second experiment, aftereffects from either internal or external features was less than that from the whole face, and did not differ from each other. While we reproduce the greater importance of internal features when presented in isolation, we find this is equally true for familiar and unfamiliar faces. The dominant influence of internal features is reduced when integrated into a whole-face context, suggesting another facet of expert face processing. Copyright © 2014 Elsevier B.V. All rights reserved.

Ambiguities of theoretical parameters and CP or T violation in neutrino factories

International Nuclear Information System (INIS)

Koike, Masafumi; Ota, Toshihiko; Sato, Joe

2002-01-01

We study the sensitivity to the CP- or T-violation search in the presence of ambiguities of the theoretical parameters. Three generations of neutrinos are considered. The parameters whose ambiguities are considered are the differences of the squared masses, the mixing angles, and the density of matter. We first consider the statistics that are sensitive to the genuine CP-violation effect originating from the imaginary coupling. No ambiguity of the parameters is considered in this part. It is argued that the widely adopted usual statistics are not necessarily sensitive to the genuine CP-violation effect. Two statistics that are sensitive to the imaginary coupling are proposed. The qualitative difference between these statistics and the usual ones are discussed. Next we proceed to the case where the ambiguity of the parameters is present. The sensitivity of the CP-violation search is greatly spoiled when the baseline length is longer than about one thousand kilometers, which turns out to be due to the ambiguity of the matter effect. Thus the CP-violation search by use of CP conjugate channels turns out to require a low energy neutrino and short baseline length. It is also shown that such a loss of sensitivity is avoided by using T-conjugate oscillation channels

Role conflict, role ambiguity and job satisfaction: Perceptions of the Brazilian controllers

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Marilu Nuñez Palomino

2016-06-01

Full Text Available ABSTRACT From early times to the present, accounting literature has recorded several situations involving role conflict and ambiguity that cause tension among controllers. The theoretical framework was comprised of the seminal work on Role Theory by Katz and Kahn (1970, and empirical evidence regarding the evolution of the role of controllers in the enterprises. In this study, we used the structural equations technique, which allowed for non-rejection of the two study hypotheses, thus providing evidence that role conflict and ambiguity adversely affect job satisfaction among Brazilian controllers. The sample was comprised of 114 controllers. An electronic questionnaire was used to collect the data, allowing information about the respondents to be captured, along with their perceptions regarding levels of role conflict and ambiguity and job satisfaction. For this, the tools developed by Rizzo, House, and Lirtzman (1970 were used, as well as the Job Satisfaction Index presented by Tarrant and Sabo (2010. The results indicated that Brazilian controllers perceive role conflict and role ambiguity while they perform their duties. Job satisfaction of the controllers isaffected more strongly by role ambiguity than by role conflict. However, despite perceiving these two tensions, executives are moderately satisfied with their current working conditions.

The inertial attitude augmentation for ambiguity resolution in SF/SE-GNSS attitude determination.

Science.gov (United States)

Zhu, Jiancheng; Hu, Xiaoping; Zhang, Jingyu; Li, Tao; Wang, Jinling; Wu, Meiping

2014-06-26

The Unaided Single Frequency/Single Epoch Global Navigation Satellite System (SF/SE GNSS) model is the most challenging scenario for ambiguity resolution in the GNSS attitude determination application. To improve the performance of SF/SE-GNSS ambiguity resolution without excessive cost, the Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS-IMU) is a proper choice for the auxiliary sensor that carries out the inertial attitude augmentation. Firstly, based on the SF/SE-GNSS compass model, the Inertial Derived Baseline Vector (IDBV) is defined to connect the MEMS-IMU attitude measurement with the SF/SE-GNSS ambiguity search space, and the mechanism of inertial attitude augmentation is revealed from the perspective of geometry. Then, through the quantitative description of model strength by Ambiguity Dilution of Precision (ADOP), two ADOPs are specified for the unaided SF/SE-GNSS compass model and its inertial attitude augmentation counterparts, respectively, and a sufficient condition is proposed for augmenting the SF/SE-GNSS model strength with inertial attitude measurement. Finally, in the framework of an integer aperture estimator with fixed failure rate, the performance of SF/SE-GNSS ambiguity resolution with inertial attitude augmentation is analyzed when the model strength is varying from strong to weak. The simulation results show that, in the SF/SE-GNSS attitude determination application, MEMS-IMU can satisfy the requirements of ambiguity resolution with inertial attitude augmentation.

The Inertial Attitude Augmentation for Ambiguity Resolution in SF/SE-GNSS Attitude Determination

Science.gov (United States)

Zhu, Jiancheng; Hu, Xiaoping; Zhang, Jingyu; Li, Tao; Wang, Jinling; Wu, Meiping

2014-01-01

The Unaided Single Frequency/Single Epoch Global Navigation Satellite System (SF/SE GNSS) model is the most challenging scenario for ambiguity resolution in the GNSS attitude determination application. To improve the performance of SF/SE-GNSS ambiguity resolution without excessive cost, the Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS-IMU) is a proper choice for the auxiliary sensor that carries out the inertial attitude augmentation. Firstly, based on the SF/SE-GNSS compass model, the Inertial Derived Baseline Vector (IDBV) is defined to connect the MEMS-IMU attitude measurement with the SF/SE-GNSS ambiguity search space, and the mechanism of inertial attitude augmentation is revealed from the perspective of geometry. Then, through the quantitative description of model strength by Ambiguity Dilution of Precision (ADOP), two ADOPs are specified for the unaided SF/SE-GNSS compass model and its inertial attitude augmentation counterparts, respectively, and a sufficient condition is proposed for augmenting the SF/SE-GNSS model strength with inertial attitude measurement. Finally, in the framework of an integer aperture estimator with fixed failure rate, the performance of SF/SE-GNSS ambiguity resolution with inertial attitude augmentation is analyzed when the model strength is varying from strong to weak. The simulation results show that, in the SF/SE-GNSS attitude determination application, MEMS-IMU can satisfy the requirements of ambiguity resolution with inertial attitude augmentation. PMID:24971472

Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance.

Science.gov (United States)

Mañas, Miguel A; Díaz-Fúnez, Pedro; Pecino, Vicente; López-Liria, Remedios; Padilla, David; Aguilar-Parra, José M

2017-01-01

In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate). In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context.

Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance

Science.gov (United States)

Mañas, Miguel A.; Díaz-Fúnez, Pedro; Pecino, Vicente; López-Liria, Remedios; Padilla, David; Aguilar-Parra, José M.

2018-01-01

In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate). In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context. PMID:29375424

Consequences of Team Job Demands: Role Ambiguity Climate, Affective Engagement, and Extra-Role Performance

Directory of Open Access Journals (Sweden)

Miguel A. Mañas

2018-01-01

Full Text Available In the absence of clearly established procedures in the workplace, employees will experience a negative affective state. This situation influences their well-being and their intention to behave in ways that benefit the organization beyond their job demands. This impact is more relevant on teamwork where members share the perception of ambiguity through emotional contagion (role ambiguity climate. In the framework of the job demands-resources model, the present study analyzes how high levels of role ambiguity climate can have such an effect to reduce employee affective engagement. Over time it has been associated with negative results for the organization due to a lack of extra-role performance. The sample included 706 employees from a multinational company, who were divided into 11 work teams. In line with the formulated hypotheses, the results confirm the negative influence of the role ambiguity climate on extra-role performance, and the mediated effect of affective engagement in the relationship between the role ambiguity climate and extra-role performance. These findings indicate that the role ambiguity climate is related to the adequate or inadequate functioning of employees within a work context.

Athletes' perceptions of role ambiguity and coaching competency in sport teams: a multilevel analysis.

Science.gov (United States)

Bosselut, Grégoire; Heuzé, Jean-Philippe; Eys, Mark A; Fontayne, Paul; Sarrazin, Philippe

2012-06-01

The purpose of this study was to examine the relationship between athletes' perceptions of role ambiguity and two theoretically derived dimensions of coaching competency (i.e., game strategy and technique competencies). A total of 243 players from 26 teams representing various interdependent sports completed French versions of the Role Ambiguity Scale and the Coaching Competency Scale. Multilevel analyses supported the existence of relationships between the four dimensions of role ambiguity and the two dimensions of coaching competency at both individual and team levels. When the levels were considered jointly, athletes perceiving greater ambiguity in their role in both offensive and defensive contexts were more critical of their coach's capacities to lead their team during competitions and to diagnose or formulate instructions during training sessions. The results also indicated that the dimension of scope of responsibilities was the main contributor to the relationship with coaching competency at an individual level, whereas role evaluation was the main contributor to this relationship at a group level. Findings are discussed in relation to the role episode model, the role ambiguity dimensions involved in the relationships according to the level of analysis considered, and the salience of ambiguity perceptions in the offensive context.

Measuring the ambiguity tolerance of medical students: a cross-sectional study from the first to sixth academic years.

Science.gov (United States)

Weissenstein, Anne; Ligges, Sandra; Brouwer, Britta; Marschall, Bernhard; Friederichs, Hendrik

2014-01-09

Tolerance of ambiguity, or the extent to which ambiguous situations are perceived as desirable, is an important component of the attitudes and behaviors of medical students. However, few studies have compared this trait across the years of medical school. General practitioners are considered to have a higher ambiguity tolerance than specialists. We compared ambiguity tolerance between general practitioners and medical students. We designed a cross-sectional study to evaluate the ambiguity tolerance of 622 medical students in the first to sixth academic years. We compared this with the ambiguity tolerance of 30 general practitioners. We used the inventory for measuring ambiguity tolerance (IMA) developed by Reis (1997), which includes three measures of ambiguity tolerance: openness to new experiences, social conflicts, and perception of insoluble problems. We obtained a total of 564 complete data sets (return rate 90.1%) from medical students and 29 questionnaires (return rate 96.7%) from general practitioners. In relation to the reference groups defined by Reis (1997), medical students had poor ambiguity tolerance on all three scales. No differences were found between those in the first and the sixth academic years, although we did observe gender-specific differences in ambiguity tolerance. We found no differences in ambiguity tolerance between general practitioners and medical students. The ambiguity tolerance of the students that we assessed was below average, and appeared to be stable throughout the course of their studies. In contrast to our expectations, the general practitioners did not have a higher level of ambiguity tolerance than the students did.

Evidence for external forcing of the Atlantic Multidecadal Oscillation since termination of the Little Ice Age.

Science.gov (United States)

Knudsen, Mads Faurschou; Jacobsen, Bo Holm; Seidenkrantz, Marit-Solveig; Olsen, Jesper

2014-02-25

The Atlantic Multidecadal Oscillation (AMO) represents a significant driver of Northern Hemisphere climate, but the forcing mechanisms pacing the AMO remain poorly understood. Here we use the available proxy records to investigate the influence of solar and volcanic forcing on the AMO over the last ~450 years. The evidence suggests that external forcing played a dominant role in pacing the AMO after termination of the Little Ice Age (LIA; ca. 1400-1800), with an instantaneous impact on mid-latitude sea-surface temperatures that spread across the North Atlantic over the ensuing ~5 years. In contrast, the role of external forcing was more ambiguous during the LIA. Our study further suggests that the Atlantic Meridional Overturning Circulation is important for linking external forcing with North Atlantic sea-surface temperatures, a conjecture that reconciles two opposing theories concerning the origin of the AMO.

The Relationship between Tolerance of Ambiguity and Stereotyping: Implications for BSW Education

Science.gov (United States)

Valutis, Stephanie A.

2015-01-01

Ambiguity tolerance and intolerance can influence one's professional practice. The study of such influences remains sparse within the social work literature. Behaviors that reduce uncertainty, including categorizing or stereotyping, are used by those who feel discomfort in ambiguous situations. This study explores explore the relationship between…

Acute stress affects risk taking but not ambiguity aversion.

Science.gov (United States)

Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

2014-01-01

Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

Space-frequency analysis and reduction of potential field ambiguity

Directory of Open Access Journals (Sweden)

A. Rapolla

1997-06-01

Full Text Available Ambiguity of depth estimation of magnetic sources via spectral analysis can be reduced representing its field via a set of space-frequency atoms. This is obtained throughout a continuous wavelet transform using a Morlet analyzing wavelet. In the phase-plane representation even a weak contribution related to deep-seated sources is clearly distinguished with respect a more intense effect of a shallow source, also in the presence of a strong noise. Furthermore, a new concept of local power spectrum allows the depth to both the sources to be correctly interpreted. Neither result can be provided by standard Fourier analysis. Another method is proposed to reduce ambiguity by inversion of potential field data lying along the vertical axis. This method allows a depth resolution to gravity or the magnetic methods and below some conditions helps to reduce their inherent ambiguity. Unlike the case of monopoles, inversion of a vertical profile of gravity data above a cubic source gives correct results for the cube side and density.

Perceptions of boundary ambiguity in the process of leaving an abusive partner.

Science.gov (United States)

Khaw, Lyndal; Hardesty, Jennifer L

2015-06-01

The process of leaving an abusive partner has been theorized using the Stages of Change Model. Although useful, this model does not account for changes in relational boundaries unique to the process of leaving. Using family stress and feminist perspectives, this study sought to integrate boundary ambiguity into the Stages of Change Model. Boundary ambiguity is defined as a perception of uncertainty as to who is in or out of a family system (Boss & Greenberg, 1984). Twenty-five mothers who had temporarily or permanently left their abusers were interviewed. Data were analyzed using constructivist grounded theory methods. Results identify types, indicators of, and mothers' responses to boundary ambiguity throughout the five stages of change. Most mothers and abusers fluctuated between physical and psychological presence and absence over multiple separations. The integration of boundary ambiguity into the Stages of Change Model highlights the process of leaving an abusive partner as systemic, fluid, and nonlinear. © 2014 Family Process Institute.

Cross-linguistic scope ambiguity: When two systems meet

Directory of Open Access Journals (Sweden)

Gregory Scontras

2017-04-01

Full Text Available Accurately recognizing and resolving ambiguity is a hallmark of linguistic ability. English is a language with scope ambiguities in doubly-quantified sentences like 'A shark ate every pirate'; this sentence can either describe a scenario with a single shark eating all of the pirates, or a scenario with many sharks—a potentially-different one eating each pirate. In Mandarin Chinese, the corresponding sentence is unambiguous, as it can only describe the single-shark scenario. We present experimental evidence to this effect, comparing native speakers of English with native speakers of Mandarin in their interpretations of doubly-quantified sentences. Having demonstrated the difference between these two languages in their ability for inverse scope interpretations, we then probe the robustness of the grammar of scope by extending our experiments to English-dominant adult heritage speakers of Mandarin. Like native speakers of Mandarin, heritage Mandarin speakers lack inverse scope in Mandarin. Crucially, these speakers also lack inverse scope in English, their dominant language in adulthood. We interpret these results as evidence for the pressure to simplify the grammar of scope, decreasing ambiguity when possible. In other words, when two systems meet—as in the case of heritage speakers—the simpler system prevails. This article is part of the special collection: Quantifier Scope

Development and biological function of the female gonads and genitalia in IGF-I deficiency -- Laron syndrome as a model.

Science.gov (United States)

Laron, Zvi

2006-01-01

Laron syndrome (LS) or primary GH insensitivity is a unique human model to study the effects of congenital IGF-I deficiency. Within our cohort of 63 patients with LS, 15 female patients were regularly followed since birth or infancy, throughout puberty. We observed that they were short at birth, with small genitalia and gonads -- during puberty, developed delayed puberty but eventually reached between 16 and 19 1/2 years full sexual development. Reproduction is unaffected at a young adult age. It is concluded that IGF-I in concert with the sex hormones has a modulatory but not essential function on female sexual development and maturation.

Authoritarianism, cognitive rigidity, and the processing of ambiguous visual information.

Science.gov (United States)

Duncan, Lauren E; Peterson, Bill E

2014-01-01

Intolerance of ambiguity and cognitive rigidity are unifying aspects of authoritarianism as defined by Adorno, Frenkel-Brunswik, Levinson, and Sanford (1982/1950), who hypothesized that authoritarians view the world in absolute terms (e.g., good or evil). Past studies have documented the relationship between authoritarianism and intolerance of ambiguity and rigidity. Frenkel-Brunswik (1949) hypothesized that this desire for absolutism was rooted in perceptual processes. We present a study with three samples that directly tests the relationship between right wing authoritarianism (RWA) and the processing of ideologically neutral but ambiguous visual stimuli. As hypothesized, in all three samples we found that RWA was related to the slower processing of visual information that required participants to recategorize objects. In a fourth sample, RWA was unrelated to speed of processing visual information that did not require recategorization. Overall, results suggest a relationship between RWA and rigidity in categorization.

Ambiguity assessment of small-angle scattering curves from monodisperse systems.

Science.gov (United States)

Petoukhov, Maxim V; Svergun, Dmitri I

2015-05-01

A novel approach is presented for an a priori assessment of the ambiguity associated with spherically averaged single-particle scattering. The approach is of broad interest to the structural biology community, allowing the rapid and model-independent assessment of the inherent non-uniqueness of three-dimensional shape reconstruction from scattering experiments on solutions of biological macromolecules. One-dimensional scattering curves recorded from monodisperse systems are nowadays routinely utilized to generate low-resolution particle shapes, but the potential ambiguity of such reconstructions remains a major issue. At present, the (non)uniqueness can only be assessed by a posteriori comparison and averaging of repetitive Monte Carlo-based shape-determination runs. The new a priori ambiguity measure is based on the number of distinct shape categories compatible with a given data set. For this purpose, a comprehensive library of over 14,000 shape topologies has been generated containing up to seven beads closely packed on a hexagonal grid. The computed scattering curves rescaled to keep only the shape topology rather than the overall size information provide a `scattering map' of this set of shapes. For a given scattering data set, one rapidly obtains the number of neighbours in the map and the associated shape topologies such that in addition to providing a quantitative ambiguity measure the algorithm may also serve as an alternative shape-analysis tool. The approach has been validated in model calculations on geometrical bodies and its usefulness is further demonstrated on a number of experimental X-ray scattering data sets from proteins in solution. A quantitative ambiguity score (a-score) is introduced to provide immediate and convenient guidance to the user on the uniqueness of the ab initio shape reconstruction from the given data set.

Phase-ambiguity resolution for QPSK modulation systems. Part 2: A method to resolve offset QPSK

Science.gov (United States)

Nguyen, Tien Manh

1989-01-01

Part 2 presents a new method to resolve the phase-ambiguity for Offset QPSK modulation systems. When an Offset Quaternary Phase-Shift-Keyed (OQPSK) communications link is utilized, the phase ambiguity of the reference carrier must be resolved. At the transmitter, two different unique words are separately modulated onto the quadrature carriers. At the receiver, the recovered carrier may have one of four possible phases, 0, 90, 180, or 270 degrees, referenced to the nominally correct phase. The IF portion of the channel may cause a phase-sense reversal, i.e., a reversal in the direction of phase rotation for a specified bit pattern. Hence, eight possible phase relationships (the so-called eight ambiguous phase conditions) between input and output of the demodulator must be resolved. Using the In-phase (I)/Quadrature (Q) channel reversal correcting property of an OQPSK Costas loop with integrated symbol synchronization, four ambiguous phase conditions are eliminated. Thus, only four possible ambiguous phase conditions remain. The errors caused by the remaining ambiguous phase conditions can be corrected by monitoring and detecting the polarity of the two unique words. The correction of the unique word polarities results in the complete phase-ambiguity resolution for the OQPSK system.

Three-frequency BDS precise point positioning ambiguity resolution based on raw observables

Science.gov (United States)

Li, Pan; Zhang, Xiaohong; Ge, Maorong; Schuh, Harald

2018-02-01

All BeiDou navigation satellite system (BDS) satellites are transmitting signals on three frequencies, which brings new opportunity and challenges for high-accuracy precise point positioning (PPP) with ambiguity resolution (AR). This paper proposes an effective uncalibrated phase delay (UPD) estimation and AR strategy which is based on a raw PPP model. First, triple-frequency raw PPP models are developed. The observation model and stochastic model are designed and extended to accommodate the third frequency. Then, the UPD is parameterized in raw frequency form while estimating with the high-precision and low-noise integer linear combination of float ambiguity which are derived by ambiguity decorrelation. Third, with UPD corrected, the LAMBDA method is used for resolving full or partial ambiguities which can be fixed. This method can be easily and flexibly extended for dual-, triple- or even more frequency. To verify the effectiveness and performance of triple-frequency PPP AR, tests with real BDS data from 90 stations lasting for 21 days were performed in static mode. Data were processed with three strategies: BDS triple-frequency ambiguity-float PPP, BDS triple-frequency PPP with dual-frequency (B1/B2) and three-frequency AR, respectively. Numerous experiment results showed that compared with the ambiguity-float solution, the performance in terms of convergence time and positioning biases can be significantly improved by AR. Among three groups of solutions, the triple-frequency PPP AR achieved the best performance. Compared with dual-frequency AR, additional the third frequency could apparently improve the position estimations during the initialization phase and under constraint environments when the dual-frequency PPP AR is limited by few satellite numbers.

AMBIGUITY OF LOCI DURING HLA-TYPING ON SSO TECHNOLOGY AND ATTEMPT TO RESOLVE THEM

Directory of Open Access Journals (Sweden)

M. A. Loginova

2010-01-01

Full Text Available Sequence specific oligonucleotides typing was used to identify human leukocyte antigen (HLA-A, B, DRB1 alleles from 705 recruited volunteers with Volga Federal District for unrelated hematopoietic stem cell registry and 155 of their number at locus HLA-C. 48 samples cannot be entered into the database because of ambiguities in the identification of allelic loci on HLA-class I – HLA-A, HLA-B. To resolution of ambiguity use reagents kits AlleleSEQR HLA Sequencing, which allowed to reveal the ambiguity of the locus HLA-A, 44% of cases, the loci HLA-B and HLA-C – 40% of cases. Application software HARPs Finder showed the possibility of resolution of all identified allelic ambiguities (with the exception of types of ambiguity – A*03/A*32 or A*74:13/A*32:04 and A*01/A*11 or A*36:04/A*11 with the addition of basic kits AlleleSEQR HLA Sequencing reagents kit Al- leleSEQR HARPs. 

Diffeomorphisms, Anomalies and the Fefferman-Graham Ambiguity

International Nuclear Information System (INIS)

Schwimmer, A.; Theisen, S.

2000-01-01

Using the Weyl transfomations induced by diffeomorphisms we set up a cohomological problem for the Fefferman-Graham coefficients. The cohomologically nontrivial solutions remove the ambiguity and give the nonlocal terms in the effective action responsible for the trace anomalies. (author)

Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

DEFF Research Database (Denmark)

Munk, Claus; Rubtsov, Alexey Vladimirovich

We solve a stock-bond-cash portfolio choice problem for a risk- and ambiguity-averse investor in a setting where the inflation rate and interest rates are stochastic. The expected inflation rate is unobservable, but the investor may learn about it from realized inflation and observed stock and bond......-Jacobi-Bellman equation in closed form and derive and illustrate a number of interesting properties of the solution. For example, ambiguity aversion affects the optimal portfolio through the correlation of price level with the stock index, a bond, and the expected inflation rate. Furthermore, unlike other settings...

United we sense, divided we fail: context-driven perception of ambiguous visual stimuli.

NARCIS (Netherlands)

Klink, P.C.; van Wezel, R.J.A.; van Ee, R.

2012-01-01

Ambiguous visual stimuli provide the brain with sensory information that contains conflicting evidence for multiple mutually exclusive interpretations. Two distinct aspects of the phenomenological experience associated with viewing ambiguous visual stimuli are the apparent stability of perception

United we sense, divided we fail: context-driven perception of ambiguous visual stimuli

NARCIS (Netherlands)

Klink, P. C; van Wezel, Richard Jack Anton; van Ee, R.

2012-01-01

Ambiguous visual stimuli provide the brain with sensory information that contains conflicting evidence for multiple mutually exclusive interpretations. Two distinct aspects of the phenomenological experience associated with viewing ambiguous visual stimuli are the apparent stability of perception

Quantum-mechanical analysis of the VRsup(n) ambiguity in the optical model

International Nuclear Information System (INIS)

Shastry, C.S.

1982-01-01

Using analytical methods and without adopting numerical calculations or semiclassical arguments, it is shown that the well known VRsup(n), n is approximately equal to 2, parameter ambiguity in the neutron-nucleus optical potential can be attributed to the closeness of the Woods-Saxon potential to the corresponding square well inside the nucleus. This parameter ambiguity is absent in individual partial waves but is more apparent in the differential cross section. The analysis is generalised to the proton-nucleus optical model. The present method clearly pinpoints the mathematical origin of the VRsup(n) ambiguity which is difficult to deduce by purely numerical methods. (author)

A motion-based integer ambiguity resolution method for attitude determination using the global positioning system (GPS)

International Nuclear Information System (INIS)

Wang, Bo; Deng, Zhihong; Wang, Shunting; Fu, Mengyin

2010-01-01

Loss of the satellite signal and noise disturbance will cause cycle slips to occur in the carrier phase observation of the attitude determination system using the global positioning system (GPS), especially in the dynamic situation. Therefore, in order to reject the error by cycle slips, the integer ambiguity should be re-computed. A motion model-based Kalman predictor is used for the ambiguity re-computation in dynamic applications. This method utilizes the correct observation of the last step to predict the current ambiguities. With the baseline length as a constraint to reject invalid values, we can solve the current integer ambiguity and the attitude angles, by substituting the obtained ambiguities into the constrained LAMBDA method. Experimental results demonstrate that the proposed method is more efficient in the dynamic situation, which takes less time to obtain new fixed ambiguities with a higher mean success rate

Novel ambiguities in the Seiberg-Witten map and the emergent gravity

International Nuclear Information System (INIS)

Muthukumar, B.

2015-01-01

A homogeneous part of the Seiberg-Witten gauge equivalence relation for gauge fields can lead to solutions that involve matter fields in such a way that the gauge equivalence and the dimensional and index structures are preserved. In particular, we consider scalar fields coupled to U(1) gauge fields. The matter fields appear non-linearly in the map. As an application, we analyze the implication of this ambiguity to emergent gravity at the first order in noncommutative parameter and show that the new ambiguity restores the possibility of conformal coupling of real scalar density field that is coupled non-minimally to the emergent gravity induced by gauge fields — a possibility that is strictly not allowed if we consider only the already known ambiguity in the Seiberg-Witten map.

Ambiguous diagnosis, futile treatments and temporary recovery ...

African Journals Online (AJOL)

Ambiguous diagnosis, futile treatments and temporary recovery: Meanings of medical treatment among HIV/AIDS family caregivers providing care without ARVs. ... to understand unstable treatment outcomes; and policy makers should strengthen home-based care by developing policies that integrate palliative care into HIV ...

On the Impact of L2 Speech Rhythm on Syntactic Ambiguity Resolution

Science.gov (United States)

Roncaglia-Denissen, M. Paula; Schmidt-Kassow, Maren; Heine, Angela; Kotz, Sonja A.

2015-01-01

In an event-related potential (ERP) study we investigated the role of age of acquisition (AoA) on the use of second language rhythmic properties during syntactic ambiguity resolution. Syntactically ambiguous sentences embedded in rhythmically regular and irregular contexts were presented to Turkish early and late second language (L2) learners of…

The Ethics of Ambiguity: Rethinking the Role and Importance of Uncertainty in Medical Education and Practice.

Science.gov (United States)

Domen, Ronald E

2016-01-01

Understanding and embracing uncertainty are critical for effective teacher-learner relationships as well as for shared decision-making in the physician-patient relationship. However, ambiguity has not been given serious consideration in either the undergraduate or graduate medical curricula or in the role it plays in patient-centered care. In this article, the author examines the ethics of ambiguity and argues for a pedagogy that includes education in the importance of, and tolerance of, ambiguity that is inherent in medical education and practice. Common threads running through the ethics of ambiguity are the virtue of respect, and the development of a culture of respect is required for the successful understanding and implementation of a pedagogy of ambiguity.

The interaction of patient race, provider bias, and clinical ambiguity on pain management decisions.

Science.gov (United States)

Hirsh, Adam T; Hollingshead, Nicole A; Ashburn-Nardo, Leslie; Kroenke, Kurt

2015-06-01

Although racial disparities in pain care are widely reported, much remains to be known about the role of provider and contextual factors. We used computer-simulated patients to examine the influence of patient race, provider racial bias, and clinical ambiguity on pain decisions. One hundred twenty-nine medical residents/fellows made assessment (pain intensity) and treatment (opioid and nonopioid analgesics) decisions for 12 virtual patients with acute pain. Race (black/white) and clinical ambiguity (high/low) were manipulated across vignettes. Participants completed the Implicit Association Test and feeling thermometers, which assess implicit and explicit racial biases, respectively. Individual- and group-level analyses indicated that race and ambiguity had an interactive effect on providers' decisions, such that decisions varied as a function of ambiguity for white but not for black patients. Individual differences across providers were observed for the effect of race and ambiguity on decisions; however, providers' implicit and explicit biases did not account for this variability. These data highlight the complexity of racial disparities and suggest that differences in care between white and black patients are, in part, attributable to the nature (ie, ambiguity) of the clinical scenario. The current study suggests that interventions to reduce disparities should differentially target patient, provider, and contextual factors. This study examined the unique and collective influence of patient race, provider racial bias, and clinical ambiguity on providers' pain management decisions. These results could inform the development of interventions aimed at reducing disparities and improving pain care. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

Absence of the Gribov ambiguity in a special algebraic gauge

Directory of Open Access Journals (Sweden)

Raval Haresh

2016-01-01

Full Text Available The Gribov ambiguity exists in various gauges except algebraic gauges. However in general, algebraic gauges are not Lorentz invariant, which is their fundamental flaw. Here we discuss a quadratic gauge fixing, which is Lorentz invariant. We show that nontrivial copies can not occur in this gauge. We then provide an example of spherically symmetric gauge field configuration and prove that with a proper boundary condition on the configuration, this gauge removes the ambiguity on a compact manifold S3${{\\mathbb S}^3}$.

An ambiguous relationship

DEFF Research Database (Denmark)

Søndergaard Larsen, Lene; Hedegaard Larsen, Birte; Birkelund, Regner

was sometimes depressing and troublesome. Really understanding and caring for fellow patients was painful. Conclusion: The patients’ interaction is characterized as ambiguous, because interaction between the patients holds both resources and strains. The patient as a care provider may cause curiosity among......Background: The significance of social interaction is commonly discussed and intensively studied as a substantial concept in the nursing profession. Social research conducted in hospital settings has prioritised to examine interaction between patients and doctors, patients and nurses and patients....... Too much information from fellow patients might rock patients’ confidence and hope for own recovery 3) a care provider; the patients’ community was characterized by compassion where they either received care from, or provided care to a fellow patient. Interacting with and supporting fellow patients...

Micro-Doppler Ambiguity Resolution for Wideband Terahertz Radar Using Intra-Pulse Interference.

Science.gov (United States)

Yang, Qi; Qin, Yuliang; Deng, Bin; Wang, Hongqiang; You, Peng

2017-04-29

Micro-Doppler, induced by micro-motion of targets, is an important characteristic of target recognition once extracted via parameter estimation methods. However, micro-Doppler is usually too significant to result in ambiguity in the terahertz band because of its relatively high carrier frequency. Thus, a micro-Doppler ambiguity resolution method for wideband terahertz radar using intra-pulse interference is proposed in this paper. The micro-Doppler can be reduced several dozen times its true value to avoid ambiguity through intra-pulse interference processing. The effectiveness of this method is proved by experiments based on a 0.22 THz wideband radar system, and its high estimation precision and excellent noise immunity are verified by Monte Carlo simulation.

46, XX male: a case study of clinical, hormonal and molecular cytogenetic evaluation of sex development disorder

International Nuclear Information System (INIS)

Ali, S.; Shahid, S.M.; Azhar, A.

2012-01-01

Disorders of sex development (DSD) create medical and social dilemma. Maleness with XX genotype is a rare genetic condition affecting one in 24,000 new-born males. The XX male syndrome is a varied condition characterized by a spectrum of clinical presentation. ranging from normal male genitalia to ambiguous sex. Chromosomal anomalies are important cause of lack of development in secondary sexual characteristics, delayed puberty, miscarriage, infertility and other associated problems. An individual having ambiguous sex may have lifelong impact on social, psychological and sexual functions. The present case study describes the hormonal, clinical and molecular cytogenetics data of sex development disorders in a patient who was phenotypically male but cytogenetic analysis revealed 46.XX. (author)

Robustness of climate metrics under climate policy ambiguity

International Nuclear Information System (INIS)

Ekholm, Tommi; Lindroos, Tomi J.; Savolainen, Ilkka

2013-01-01

Highlights: • We assess the economic impacts of using different climate metrics. • The setting is cost-efficient scenarios for three interpretations of the 2C target. • With each target setting, the optimal metric is different. • Therefore policy ambiguity prevents the selection of an optimal metric. • Robust metric values that perform well with multiple policy targets however exist. -- Abstract: A wide array of alternatives has been proposed as the common metrics with which to compare the climate impacts of different emission types. Different physical and economic metrics and their parameterizations give diverse weights between e.g. CH 4 and CO 2 , and fixing the metric from one perspective makes it sub-optimal from another. As the aims of global climate policy involve some degree of ambiguity, it is not possible to determine a metric that would be optimal and consistent with all policy aims. This paper evaluates the cost implications of using predetermined metrics in cost-efficient mitigation scenarios. Three formulations of the 2 °C target, including both deterministic and stochastic approaches, shared a wide range of metric values for CH 4 with which the mitigation costs are only slightly above the cost-optimal levels. Therefore, although ambiguity in current policy might prevent us from selecting an optimal metric, it can be possible to select robust metric values that perform well with multiple policy targets

Impact of Decorrelation on Search Efficiency of Ambiguity Resolution

Directory of Open Access Journals (Sweden)

LU Liguo

2015-05-01

Full Text Available The decorrelation performance of LAMBDA algorithm, LLL algorithm and Seysen algorithm are analyzed with evaluation indexes, i.e., condition number, orthogonal defect and S(A. Moreover, relationships between decorrelation performance of the above algorithms and ambiguity search efficiency are evaluated using theoretical and practical validation, respectively. The results validate that there is no inevitable relation between decorrelation performance of variance-covariance matrix of original ambiguity and search efficiency, whereas, traditional views consider that search efficiency can be enhanced just by improving decorrelation performance. Further analysis shows that the essence to improving search efficiency major depends on the permutation of basis vectors according to a certain direction.

Making Decisions under Ambiguity: Judgment Bias Tasks for Assessing Emotional State in Animals

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Roelofs, Sanne; Boleij, Hetty; Nordquist, Rebecca E.; van der Staay, Franz Josef

2016-01-01

Judgment bias tasks (JBTs) are considered as a family of promising tools in the assessment of emotional states of animals. JBTs provide a cognitive measure of optimism and/or pessimism by recording behavioral responses to ambiguous stimuli. For instance, a negative emotional state is expected to produce a negative or pessimistic judgment of an ambiguous stimulus, whereas a positive emotional state produces a positive or optimistic judgment of the same ambiguous stimulus. Measuring an animal’s emotional state or mood is relevant in both animal welfare research and biomedical research. This is reflected in the increasing use of JBTs in both research areas. We discuss the different implementations of JBTs with animals, with a focus on their potential as an accurate measure of emotional state. JBTs have been successfully applied to a very broad range of species, using many different types of testing equipment and experimental protocols. However, further validation of this test is deemed necessary. For example, the often extensive training period required for successful judgment bias testing remains a possible factor confounding results. Also, the issue of ambiguous stimuli losing their ambiguity with repeated testing requires additional attention. Possible improvements are suggested to further develop the JBTs in both animal welfare and biomedical research. PMID:27375454

Emotion and decision-making under uncertainty: Physiological arousal predicts increased gambling during ambiguity but not risk.

Science.gov (United States)

FeldmanHall, Oriel; Glimcher, Paul; Baker, Augustus L; Phelps, Elizabeth A

2016-10-01

Uncertainty, which is ubiquitous in decision-making, can be fractionated into known probabilities (risk) and unknown probabilities (ambiguity). Although research has illustrated that individuals more often avoid decisions associated with ambiguity compared to risk, it remains unclear why ambiguity is perceived as more aversive. Here we examine the role of arousal in shaping the representation of value and subsequent choice under risky and ambiguous decisions. To investigate the relationship between arousal and decisions of uncertainty, we measure skin conductance response-a quantifiable measure reflecting sympathetic nervous system arousal-during choices to gamble under risk and ambiguity. To quantify the discrete influences of risk and ambiguity sensitivity and the subjective value of each option under consideration, we model fluctuating uncertainty, as well as the amount of money that can be gained by taking the gamble. Results reveal that although arousal tracks the subjective value of a lottery regardless of uncertainty type, arousal differentially contributes to the computation of value-that is, choice-depending on whether the uncertainty is risky or ambiguous: Enhanced arousal adaptively decreases risk-taking only when the lottery is highly risky but increases risk-taking when the probability of winning is ambiguous (even after controlling for subjective value). Together, this suggests that the role of arousal during decisions of uncertainty is modulatory and highly dependent on the context in which the decision is framed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

In Command And Out Of Control: Leaders Developing Teams That Thrive In Chaos And Ambiguity

Science.gov (United States)

2016-05-26

In Command and Out of Control: Leaders Developing Teams that Thrive in Chaos and Ambiguity A Monograph by...TITLE AND SUBTITLE Sa. CONTRACT NUMBER In Command and Out of Control: Leaders Developing Teams that Thrive in Chaos and Ambiguity Sb. GRANT NUMBER...the chaos and ambiguity associated with war. Teams must provide the innovative and creative solutions formerly left to the individual leader. This

Exploring Situated Ambiguity in Students' Entrepreneurial Learning

Science.gov (United States)

Kubberød, Elin; Pettersen, Inger Beate

2017-01-01

Purpose: Building on entrepreneurial learning research, the purpose of this paper is to argue that the students participating in foreign entrepreneurial education programmes can have realistic entrepreneurial learning experiences. This research addresses two specific questions: how situated ambiguity induced by a foreign culture may contribute to…

Hippocampal Processing of Ambiguity Enhances Fear Memory.

Science.gov (United States)

Amadi, Ugwechi; Lim, Seh Hong; Liu, Elizabeth; Baratta, Michael V; Goosens, Ki A

2017-02-01

Despite the ubiquitous use of Pavlovian fear conditioning as a model for fear learning, the highly predictable conditions used in the laboratory do not resemble real-world conditions, in which dangerous situations can lead to unpleasant outcomes in unpredictable ways. In the current experiments, we varied the timing of aversive events after predictive cues in rodents and discovered that temporal ambiguity of aversive events greatly enhances fear. During fear conditioning with unpredictably timed aversive events, pharmacological inactivation of the dorsal hippocampus or optogenetic silencing of cornu ammonis 1 cells during aversive negative prediction errors prevented this enhancement of fear without affecting fear learning for predictable events. Dorsal hippocampal inactivation also prevented ambiguity-related enhancement of fear during auditory fear conditioning under a partial-reinforcement schedule. These results reveal that information about the timing and occurrence of aversive events is rapidly acquired and that unexpectedly timed or omitted aversive events generate hippocampal signals to enhance fear learning.

Learning, Teaching and Ambiguity in Virtual Worlds

Science.gov (United States)

Carr, Diane; Oliver, Martin; Burn, Andrew

What might online communities and informal learning practices teach us about virtual world pedagogy? In this chapter we describe a research project in which learning practices in online worlds such as World of Warcraft and Second LifeTM (SL) were investigated. Working within an action research framework, we employed a range of methods to investigate how members of online communities define the worlds they encounter, negotiate the terms of participation, and manage the incremental complexity of game worlds. The implications of such practices for online pedagogy were then explored through teaching in SL. SL eludes simple definitions. Users, or "residents", of SL partake of a range of pleasures and activities - socialising, building, creating and exhibiting art, playing games, exploring, shopping, or running a business, for instance. We argue that the variable nature of SL gives rise to degrees of ambiguity. This ambiguity impacts on inworld social practices, and has significant implications for online teaching and learning.

Obstetricians' choice of cesarean delivery in ambiguous cases

DEFF Research Database (Denmark)

Fuglenes, Dorthe; Oian, Pål; Kristiansen, Ivar Sønbø

2009-01-01

OBJECTIVE: The aim of this study was to test the hypothesis that obstetricians' choice of delivery method is influenced by their risk attitude and perceived risk of complaints and malpractice litigation. STUDY DESIGN: The choice of delivery method in ambiguous cases was studied in a nationwide...... survey of Norwegian obstetricians (n = 716; response rate, 71%) using clinical scenarios. The risk attitude was measured by 6 items from the Jackson Personality Inventory-Revised. RESULTS: The proportion of obstetricians consenting to the cesarean request varied both within and across the scenarios....... The perceived risk of complaints and malpractice litigation was a clear determinant of obstetricians' choice of cesarean in all of the clinical scenarios, whereas no impact was observed for risk attitude. CONCLUSION: Obstetricians' judgments about cesarean request in ambiguous clinical cases vary considerably...

Mentoring relationships and the levels of role conflict and role ambiguity experienced by novice nursing faculty.

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Specht, Jennifer A

2013-01-01

This study explored the effect of mentoring on the levels of role conflict and role ambiguity experienced by novice nursing faculty related to their transitions into academe using a descriptive, comparative design. It also measured the relationship between the quality of mentoring experiences of novice nursing faculty and their levels of role conflict and role ambiguity using a correlational design. P. Benner's (1984) novice to expert model was utilized as a framework for successful role transition. J. R. Rizzo, R. J. House, and S. I. Lirtzman's (1970) role conflict and role ambiguity scale was used to measure the levels of role conflict and role ambiguity experienced by novice nursing faculty. Results indicate that participants (n = 224) who were mentored have significantly lower levels of role conflict (M = 3.57) and role ambiguity (M = 3.02) than those who were not mentored (M = 4.62 and M = 3.90, respectively). Also significant, the higher the participants' reported levels of quality of mentoring experiences were, the lower their levels of role conflict and role ambiguity were. The results of this study indicate that mentoring eases the transition of novice nursing faculty from practice into academe by decreasing the degree of role ambiguity and role conflict that they experience. © 2013.

Medical Student and Junior Doctors' Tolerance of Ambiguity: Development of a New Scale

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Hancock, Jason; Roberts, Martin; Monrouxe, Lynn; Mattick, Karen

2015-01-01

The practice of medicine involves inherent ambiguity, arising from limitations of knowledge, diagnostic problems, complexities of treatment and outcome and unpredictability of patient response. Research into doctors' tolerance of ambiguity is hampered by poor conceptual clarity and inadequate measurement scales. We aimed to create and pilot a…

The tell-tale heart: physiological reactivity during resolution of ambiguity in youth anxiety.

Science.gov (United States)

Rozenman, Michelle; Vreeland, Allison; Iglesias, Marisela; Mendez, Melissa; Piacentini, John

2018-03-01

In the past decade, cognitive biases and physiological arousal have each been proposed as mechanisms through which paediatric anxiety develops and is maintained over time. Preliminary studies have found associations between anxious interpretations of ambiguity, physiological arousal, and avoidance, supporting theories that link cognition, psychophysiology, and behaviour. However, little is known about the relationship between youths' resolutions of ambiguity and physiological arousal during acute stress. Such information may have important clinical implications for use of verbal self-regulation strategies and cognitive restructuring during treatments for paediatric anxiety. In this brief report, we present findings suggesting that anxious, but not typically developing, youth select avoidant goals via non-threatening resolution of ambiguity during a stressor, and that this resolution of ambiguity is accompanied by physiological reactivity (heart rate, heart rate variability, and respiratory sinus arrhythmia). We propose future empirical research on the interplay between interpretation bias, psychophysiology, and child anxiety, as well as clinical implications.

Resolving the sign ambiguity in ΔΓs with Bs→DsK

International Nuclear Information System (INIS)

Nandi, Soumitra; Nierste, Ulrich

2008-01-01

The analysis of tagged B s →J/ψφ decays determines the CP phase φ s in B s -B s mixing with a twofold ambiguity. The solutions differ in the sign of cosφ s which equals the sign of the width difference ΔΓ s among the two B s mass eigenstates. We point out that this ambiguity can be removed with the help of B s →D s K decays. We compare untagged and tagged strategies and find the tagged analysis more promising. The removal of the sign ambiguity in ΔΓ s can be done with relatively low statistics and could therefore be a target for the early stage of B s →D s K studies.

Ambiguity Of Doppler Centroid In Synthetic-Aperture Radar

Science.gov (United States)

Chang, Chi-Yung; Curlander, John C.

1991-01-01

Paper discusses performances of two algorithms for resolution of ambiguity in estimated Doppler centroid frequency of echoes in synthetic-aperture radar. One based on range-cross-correlation technique, other based on multiple-pulse-repetition-frequency technique.

The input ambiguity hypothesis and case blindness: an account of cross-linguistic and intra-linguistic differences in case errors.

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Pelham, Sabra D

2011-03-01

English-acquiring children frequently make pronoun case errors, while German-acquiring children rarely do. Nonetheless, German-acquiring children frequently make article case errors. It is proposed that when child-directed speech contains a high percentage of case-ambiguous forms, case errors are common in child language; when percentages are low, case errors are rare. Input to English and German children was analyzed for percentage of case-ambiguous personal pronouns on adult tiers of corpora from 24 English-acquiring and 24 German-acquiring children. Also analyzed for German was the percentage of case-ambiguous articles. Case-ambiguous pronouns averaged 63·3% in English, compared with 7·6% in German. The percentage of case-ambiguous articles in German was 77·0%. These percentages align with the children's errors reported in the literature. It appears children may be sensitive to levels of ambiguity such that low ambiguity may aid error-free acquisition, while high ambiguity may blind children to case distinctions, resulting in errors.

An ambiguous relationship

DEFF Research Database (Denmark)

Søndergaard Larsen, Lene; Hedegaard Larsen, Birte; Birkelund, Regner

2013-01-01

to qualitative data analysis. Results:  The qualitative meta-synthesis resulted in the heading An Ambiguous Relationship under which three core categories illustrate the hospitalized patients’ different interaction roles. The core categories were as follows: (i) the fellow patient experienced as an enforced......Aim:  The aim of this study was to provide a clear view of the existing knowledge regarding patients’ significance to fellow patients during hospitalization. Method:  Sandelowski and Barroso’s approach to qualitative meta-synthesis was selected and systematically used for collecting and assessing...... findings from qualitative studies. Data consisted of seven qualitative studies published as one book, four scientific articles and two doctoral theses from Scotland, UK, Norway and Denmark. The analysis and synthesis were conducted with inspiration from both Sandelowski and Barroso and Ian Dey’s approach...

Searching for the best model: ambiguity of inverse solutions and application to fetal magnetoencephalography

International Nuclear Information System (INIS)

Vrba, J; Robinson, S E; McCubbin, J; Lowery, C L; Eswaran, H; Murphy, P; Preissl, H

2007-01-01

Fetal brain signals produce weak magnetic fields at the maternal abdominal surface. In the presence of much stronger interference these weak fetal fields are often nearly indistinguishable from noise. Our initial objective was to validate these weak fetal brain fields by demonstrating that they agree with the electromagnetic model of the fetal brain. The fetal brain model is often not known and we have attempted to fit the data to not only the brain source position, orientation and magnitude, but also to the brain model position. Simulation tests of this extended model search on fetal MEG recordings using dipole fit and beamformers revealed a region of ambiguity. The region of ambiguity consists of a family of models which are not distinguishable in the presence of noise, and which exhibit large and comparable SNR when beamformers are used. Unlike the uncertainty of a dipole fit with known model plus noise, this extended ambiguity region yields nearly identical forward solutions, and is only weakly dependent on noise. The ambiguity region is located in a plane defined by the source position, orientation, and the true model centre, and will have a diameter approximately 0.67 of the modelled fetal head diameter. Existence of the ambiguity region allows us to only state that the fetal brain fields do not contradict the electromagnetic model; we can associate them with a family of models belonging to the ambiguity region, but not with any specific model. In addition to providing a level of confidence in the fetal brain signals, the ambiguity region knowledge in combination with beamformers allows detection of undistorted temporal waveforms with improved signal-to-noise ratio, even though the source position cannot be uniquely determined

Sealed bid auctions with ambiguity: an experimental study

Czech Academy of Sciences Publication Activity Database

Chen, Y.; Katuščák, Peter; Ozdenoren, E.

-, č. 269 (2005), s. 1-75 ISSN 1211-3298 Institutional research plan: CEZ:AV0Z70850503 Keywords : sealed bid auctions * ambiguity * experiment Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp269.pdf

Is ambiguity tolerance malleable? Experimental evidence with potential implications for future research

Directory of Open Access Journals (Sweden)

Megan L Endres

2015-05-01

Full Text Available We conducted two research studies to address the malleability of TA by manipulating situational ambiguity. Students participated in a semester-end assessment of their management skills (n = 306. In Study 1, students in low and moderate ambiguity conditions had significantly higher post-experiment TA, more positive change in self-efficacy, and marginally higher faculty ratings. In Study 2, a control group (n = 103 did not participate in the assessment and was established for comparison to the first study results. The Study 2 students reported TA significantly lower than Study 1 students in the low and moderate ambiguity conditions. The control group TA was not significantly different from that of the Study 1 high ambiguity condition. This further suggested TA’s situational malleability, as those who had controlled access to structured information appeared to have increased their TA over that observed in the other two groups. These results suggest that TA may be malleable. We review the relevant literature, offer hypotheses, report our analyses and findings, and then propose future research and potential prescriptive applications in such areas as management development, assessment, and decision-making.

An integer ambiguity resolution method for the global positioning system (GPS)-based land vehicle attitude determination

International Nuclear Information System (INIS)

Wang, Bo; Miao, Lingjuan; Wang, Shunting; Shen, Jun

2009-01-01

During attitude determination using a global positioning system (GPS), cycle slips occur due to the loss of lock and noise disturbance. Therefore, the integer ambiguity needs re-computation to isolate the error in carrier phase. This paper presents a fast method for integer ambiguity resolution for land vehicle application. After the cycle slips are detected, the velocity vector is utilized to obtain the rough baseline vector. The obtained baseline vector is substituted into carrier phase observation equations to solve the float ambiguity solution which can be used as a constraint to accelerate the integer ambiguity search procedure at next epochs. The probability of correct integer estimation in the expanded search space is analyzed. Experimental results demonstrate that the proposed method gives a fast approach to obtain new fixed ambiguities while the regular method takes longer time and sometimes results in incorrect solutions

Sensitivity to Referential Ambiguity in Discourse: The Role of Attention, Working Memory, and Verbal Ability.

Science.gov (United States)

Boudewyn, Megan A; Long, Debra L; Traxler, Matthew J; Lesh, Tyler A; Dave, Shruti; Mangun, George R; Carter, Cameron S; Swaab, Tamara Y

2015-12-01

The establishment of reference is essential to language comprehension. The goal of this study was to examine listeners' sensitivity to referential ambiguity as a function of individual variation in attention, working memory capacity, and verbal ability. Participants listened to stories in which two entities were introduced that were either very similar (e.g., two oaks) or less similar (e.g., one oak and one elm). The manipulation rendered an anaphor in a subsequent sentence (e.g., oak) ambiguous or unambiguous. EEG was recorded as listeners comprehended the story, after which participants completed tasks to assess working memory, verbal ability, and the ability to use context in task performance. Power in the alpha and theta frequency bands when listeners received critical information about the discourse entities (e.g., oaks) was used to index attention and the involvement of the working memory system in processing the entities. These measures were then used to predict an ERP component that is sensitive to referential ambiguity, the Nref, which was recorded when listeners received the anaphor. Nref amplitude at the anaphor was predicted by alpha power during the earlier critical sentence: Individuals with increased alpha power in ambiguous compared with unambiguous stories were less sensitive to the anaphor's ambiguity. Verbal ability was also predictive of greater sensitivity to referential ambiguity. Finally, increased theta power in the ambiguous compared with unambiguous condition was associated with higher working-memory span. These results highlight the role of attention and working memory in referential processing during listening comprehension.

[Urological emergencies at the Dakar university teaching hospital: epidemiological, clinical and therapeutic features].

Science.gov (United States)

Fall, B; Diao, B; Fall, P A; Diallo, Y; Sow, Y; Ondongo, A A M; Diagana, M; Ndoye, A K; Ba, M; Diagne, B A

2008-11-01

To present the epidemiological, clinical and therapeutic features of the urological emergencies in Senegal, West Africa. The authors conducted a 20 months retrospective study that analyzed the epidemiological, clinical and therapeutic features of all urological emergencies admitted to the urology department of the university teaching hospital Aristide-Le-Dantec (Dakar). There were 1237 urological emergencies. The mean age of the patients was 58.8 years (range one month-94 years). The sex ratio (M/F) was 20.32. These patients had an age equal to or higher than 60 years in 50.7% of the cases. The most frequent illness was urinary retention (53%) and genitor-urinary system infectious, which represented as a whole 16.4% of the cases. The gangrenes of male external genitalia (Fournier's gangrene) accounted for 4.1% of the cases and the priapism 1.3%. In emergency, 331 surgical operations were performed. The most performed procedures were the installation of a suprapubic catheter (59.8%) and debridement of a gangrene of male external genitalia (15.4%). The most frequent urological emergency in our country was the acute urinary retention. Some serious illness like gangrene of male external genitalia (Fournier's gangrene) and priapism are not rare there.

Role Conflict and Ambiguity as Predictors of Job Satisfaction in High School Counselors

Science.gov (United States)

Cervoni, Annemarie; DeLucia-Waack, Janice

2011-01-01

The purpose of this study was to examine the relationship between role conflict and role ambiguity, and percentage of time spent on ASCA recommended duties (counseling, coordination, consultation, and large group guidance); and job satisfaction of high school counselors. The Role Conflict and Role Ambiguity Scale and the Job Descriptive Index were…

The ambiguous challenge of intranets

DEFF Research Database (Denmark)

Thommesen, Jacob

2003-01-01

increases with tendencies to cooperate and communicate across organisational boundaries, mainly as a reaction to developments in markets and industrial knowledge base, but also due to the potential provided by computer network. In the third chapter I identify some characteristics of two fundamental intranet...... media, email and the web, partly in the perspective of media richness theory, partly compared with philosophical discussions of classical media. The fourth chapter presents an intranet in a global company, in which problems and challenges related to ambiguity have proven significant....

From expert generalists to ambiguity masters: using ambiguity tolerance theory to redefine the practice of rural nurses.

Science.gov (United States)

Knight, Kaye; Kenny, Amanda; Endacott, Ruth

2016-06-01

To redefine the practice of rural nurses and describe a model that conceptualises the capabilities and characteristics required in the rural environment. The way in which the practice of rural nurses has been conceptualised is problematic. Definitions of rural nursing have been identified primarily through the functional context of rural health service delivery. The expert generalist term has provided a foundation theory for rural nurses with understandings informed by the scope of practice needed to meet service delivery requirements. However, authors exploring intrinsic characteristics of rural nurses have challenged this definition, as it does not adequately address the deeper, intangible complexities of practice required in the rural context. Despite this discourse, an alternative way to articulate the distinctive nature of rural nursing practice has eluded authors in Australia and internationally. A theoretical paper based on primary research. The development of the model was informed by the findings of a study that explored the nursing practice of managing telephone presentations in rural health services in Victoria, Australia. The study involved policy review from State and Federal governments, nursing and medical professional bodies, and five rural health services; semi-structured interviews with eight Directors of Nursing, seven registered nurses and focus group interviews with eight registered nurses. An ambiguity tolerance model drawn from corporate global entrepreneurship theory was adapted to explain the findings of the study. The adapted model presents capabilities and characteristics used by nurses to successfully manage the ambiguity of providing care in the rural context. Redefining the practice of rural nurses, through an adapted theory of ambiguity tolerance, highlights nursing characteristics and capabilities required in the rural context. This perspective offers new ways of thinking about the work of rural nurses, rural nurse policy, education

Effect of Changing Governance System: Result of Western Style Management Adoption to Japanese Culture of Ambiguity

Directory of Open Access Journals (Sweden)

Kohichiro Hotta

2009-02-01

Full Text Available This paper considers the difficulty of management style change through observation of the management style of Company-A, one of the biggest Japanese IT companies. Japanese economy grew after World War II until the early 1990's. During that era, Ba or SECI process worked in Japanese organizations very well. Further, there was an ambiguous culture in the background of such characteristics. Some kinds of ambiguity or adhocracy made positive effects for Japanese organizational activity, or ambiguity played an important role for Ba activity. There were nested Ba's in each organization with ambiguity. Ambiguous descriptions of roles for each organizational unit activated nested Ba's and generated hot groups. After the economic crisis, Company-A changed its governance and gave clear targets for each organizational unit and for each employee. This change gave new difficulty and diminishes its competence. The change denied the ambiguity in the organization but it was the basis of the competence. Adopting a new system of governance is not a simple activity. Systems must be adjusted to the culture of the organization. Company-A should study competitors in different cultures and adjust the methodology for its culture.

Interpretative bias in spider phobia: Perception and information processing of ambiguous schematic stimuli.

Science.gov (United States)

Haberkamp, Anke; Schmidt, Filipp

2015-09-01

This study investigates the interpretative bias in spider phobia with respect to rapid visuomotor processing. We compared perception, evaluation, and visuomotor processing of ambiguous schematic stimuli between spider-fearful and control participants. Stimuli were produced by gradually morphing schematic flowers into spiders. Participants rated these stimuli related to their perceptual appearance and to their feelings of valence, disgust, and arousal. Also, they responded to the same stimuli within a response priming paradigm that measures rapid motor activation. Spider-fearful individuals showed an interpretative bias (i.e., ambiguous stimuli were perceived as more similar to spiders) and rated spider-like stimuli as more unpleasant, disgusting, and arousing. However, we observed no differences between spider-fearful and control participants in priming effects for ambiguous stimuli. For non-ambiguous stimuli, we observed a similar enhancement for phobic pictures as has been reported previously for natural images. We discuss our findings with respect to the visual representation of morphed stimuli and to perceptual learning processes. Copyright © 2015 Elsevier B.V. All rights reserved.

Flexible taxonomic assignment of ambiguous sequencing reads

Directory of Open Access Journals (Sweden)

Jansson Jesper

2011-01-01

Full Text Available Abstract Background To characterize the diversity of bacterial populations in metagenomic studies, sequencing reads need to be accurately assigned to taxonomic units in a given reference taxonomy. Reads that cannot be reliably assigned to a unique leaf in the taxonomy (ambiguous reads are typically assigned to the lowest common ancestor of the set of species that match it. This introduces a potentially severe error in the estimation of bacteria present in the sample due to false positives, since all species in the subtree rooted at the ancestor are implicitly assigned to the read even though many of them may not match it. Results We present a method that maps each read to a node in the taxonomy that minimizes a penalty score while balancing the relevance of precision and recall in the assignment through a parameter q. This mapping can be obtained in time linear in the number of matching sequences, because LCA queries to the reference taxonomy take constant time. When applied to six different metagenomic datasets, our algorithm produces different taxonomic distributions depending on whether coverage or precision is maximized. Including information on the quality of the reads reduces the number of unassigned reads but increases the number of ambiguous reads, stressing the relevance of our method. Finally, two measures of performance are described and results with a set of artificially generated datasets are discussed. Conclusions The assignment strategy of sequencing reads introduced in this paper is a versatile and a quick method to study bacterial communities. The bacterial composition of the analyzed samples can vary significantly depending on how ambiguous reads are assigned depending on the value of the q parameter. Validation of our results in an artificial dataset confirm that a combination of values of q produces the most accurate results.

The Ambiguous Role of Constraints in Creativity

DEFF Research Database (Denmark)

Biskjær, Michael Mose; Onarheim, Balder; Wiltschnig, Stefan

2011-01-01

The relationship between creativity and constraints is often described in the literature either in rather imprecise, general concepts or in relation to very specific domains. Cross-domain and cross-disciplinary takes on how the handling of constraints influences creative activities are rare. In t......-disciplinary research into the ambiguous role of constraints in creativity....

Dealing with behavioral ambiguity in textual process descriptions

NARCIS (Netherlands)

van der Aa, Han; Leopold, Henrik; Reijers, Hajo A.

2016-01-01

Textual process descriptions are widely used in organizations since they can be created and understood by virtually everyone. The inherent ambiguity of natural language, however, impedes the automated analysis of textual process descriptions. While human readers can use their context knowledge to

Sealed bid auctions with ambiguity: theory and experiments

Czech Academy of Sciences Publication Activity Database

Chen, Y.; Katuščák, Peter; Ozdenoren, E.

2007-01-01

Roč. 136, č. 1 (2007), s. 513-535 ISSN 0022-0531 R&D Projects: GA MŠk LC542 Institutional research plan: CEZ:MSM0021620846 Keywords : sealed bid auctions * ambiguity * experiment Subject RIV: AH - Economics Impact factor: 1.353, year: 2007

Audiovisual Capture with Ambiguous Audiovisual Stimuli

Directory of Open Access Journals (Sweden)

Jean-Michel Hupé

2011-10-01

Full Text Available Audiovisual capture happens when information across modalities get fused into a coherent percept. Ambiguous multi-modal stimuli have the potential to be powerful tools to observe such effects. We used such stimuli made of temporally synchronized and spatially co-localized visual flashes and auditory tones. The flashes produced bistable apparent motion and the tones produced ambiguous streaming. We measured strong interferences between perceptual decisions in each modality, a case of audiovisual capture. However, does this mean that audiovisual capture occurs before bistable decision? We argue that this is not the case, as the interference had a slow temporal dynamics and was modulated by audiovisual congruence, suggestive of high-level factors such as attention or intention. We propose a framework to integrate bistability and audiovisual capture, which distinguishes between “what” competes and “how” it competes (Hupé et al., 2008. The audiovisual interactions may be the result of contextual influences on neural representations (“what” competes, quite independent from the causal mechanisms of perceptual switches (“how” it competes. This framework predicts that audiovisual capture can bias bistability especially if modalities are congruent (Sato et al., 2007, but that is fundamentally distinct in nature from the bistable competition mechanism.

A few approaches to remove ambiguous factors in x-ray spectrum analysis

International Nuclear Information System (INIS)

Sera, K.; Futatsugawa, S.

1993-01-01

A few attempts have been done to reduce ambiguous factors in the analysis of complex x-ray spectra. Uncertainty in peak identification and separation due to overlapping of x-ray peaks can be reduced by taking into account the response function of x-ray peaks and by using peak functions including all the x-ray sub-lines in a x-ray series. Ambiguous factors due to discontinuity of backgrounds which is sometimes followed by huge peaks can be reduced by considering contributions from the pile-up, escape and tail functions. The problem of uncertainty in the background fitting in a region of low x-ray energy, where many peaks overlap each other and determination of the background function contains much difficulties and ambiguities, can be solved by using peak functions involving tails in place of Gaussians. (author)

Visual working memory contents bias ambiguous structure from motion perception.

Directory of Open Access Journals (Sweden)

Lisa Scocchia

Full Text Available The way we perceive the visual world depends crucially on the state of the observer. In the present study we show that what we are holding in working memory (WM can bias the way we perceive ambiguous structure from motion stimuli. Holding in memory the percept of an unambiguously rotating sphere influenced the perceived direction of motion of an ambiguously rotating sphere presented shortly thereafter. In particular, we found a systematic difference between congruent dominance periods where the perceived direction of the ambiguous stimulus corresponded to the direction of the unambiguous one and incongruent dominance periods. Congruent dominance periods were more frequent when participants memorized the speed of the unambiguous sphere for delayed discrimination than when they performed an immediate judgment on a change in its speed. The analysis of dominance time-course showed that a sustained tendency to perceive the same direction of motion as the prior stimulus emerged only in the WM condition, whereas in the attention condition perceptual dominance dropped to chance levels at the end of the trial. The results are explained in terms of a direct involvement of early visual areas in the active representation of visual motion in WM.

Constant resolution of time-dependent Hartree--Fock phase ambiguity

International Nuclear Information System (INIS)

Lichtner, P.C.; Griffin, J.J.; Schultheis, H.; Schultheis, R.; Volkov, A.B.

1978-01-01

The customary time-dependent Hartree--Fock problem is shown to be ambiguous up to an arbitrary function of time additive to H/sub HF/, and, consequently, up to an arbitrary time-dependent phase for the solution, PHI(t). The ''constant'' (H)'' phase is proposed as the best resolution of this ambiguity. It leads to the following attractive features: (a) the time-dependent Hartree--Fock (TDHF) Hamiltonian, H/sub HF/, becomes a quantity whose expectation value is equal to the average energy and, hence, constant in time; (b) eigenstates described exactly by determinants, have time-dependent Hartree--Fock solutions identical with the exact time-dependent solutions; (c) among all possible TDHF solutions this choice minimizes the norm of the quantity (H--i dirac constant delta/delta t) operating on the ket PHI, and guarantees optimal time evolution over an infinitesimal period; (d) this choice corresponds both to the stationary value of the absolute difference between (H) and (i dirac constant delta/delta t) and simultaneously to its absolute minimal value with respect to choice of the time-dependent phase. The source of the ambiguity is discussed. It lies in the time-dependent generalization of the freedom to transform unitarily among the single-particle states of a determinant at the (physically irrelevant for stationary states) cost of altering only a factor of unit magnitude

Static vs Dynamic Auctions with Ambiguity Averse Bidders

NARCIS (Netherlands)

Carvalho, M.

2012-01-01

Abstract: This paper presents the outcome of a dynamic price-descending auction when the distribution of the private values is uncertain and bidders exhibit ambiguity aversion. In contrast to sealed-bid auctions, in open auctions the bidders get information about the other bidders' private values

Resolution of ambiguities in cartoons as an illustration of the role of pragmatics in natural language understanding by computers

Energy Technology Data Exchange (ETDEWEB)

Mazlack, L.J.; Paz, N.M.

1983-01-01

Newspaper cartoons can graphically display the result of ambiguity in human speech; the result can be unexpected and funny. Likewise, computer analysis of natural language statements also needs to successfully resolve ambiguous situations. Computer techniques already developed use restricted world knowledge in resolving ambiguous language use. This paper illustrates how these techniques can be used in resolving ambiguous situations arising in cartoons. 8 references.

Computational study of depth completion consistent with human bi-stable perception for ambiguous figures.

Science.gov (United States)

Mitsukura, Eiichi; Satoh, Shunji

2018-03-01

We propose a computational model that is consistent with human perception of depth in "ambiguous regions," in which no binocular disparity exists. Results obtained from our model reveal a new characteristic of depth perception. Random dot stereograms (RDS) are often used as examples because RDS provides sufficient disparity for depth calculation. A simple question confronts us: "How can we estimate the depth of a no-texture image region, such as one on white paper?" In such ambiguous regions, mathematical solutions related to binocular disparities are not unique or indefinite. We examine a mathematical description of depth completion that is consistent with human perception of depth for ambiguous regions. Using computer simulation, we demonstrate that resultant depth-maps qualitatively reproduce human depth perception of two kinds. The resultant depth maps produced using our model depend on the initial depth in the ambiguous region. Considering this dependence from psychological viewpoints, we conjecture that humans perceive completed surfaces that are affected by prior-stimuli corresponding to the initial condition of depth. We conducted psychological experiments to verify the model prediction. An ambiguous stimulus was presented after a prior stimulus removed ambiguity. The inter-stimulus interval (ISI) was inserted between the prior stimulus and post-stimulus. Results show that correlation of perception between the prior stimulus and post-stimulus depends on the ISI duration. Correlation is positive, negative, and nearly zero in the respective cases of short (0-200 ms), medium (200-400 ms), and long ISI (>400 ms). Furthermore, based on our model, we propose a computational model that can explain the dependence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Improving Ambiguity Resolution for Medium Baselines Using Combined GPS and BDS Dual/Triple-Frequency Observations.

Science.gov (United States)

Gao, Wang; Gao, Chengfa; Pan, Shuguo; Wang, Denghui; Deng, Jiadong

2015-10-30

The regional constellation of the BeiDou navigation satellite system (BDS) has been providing continuous positioning, navigation and timing services since 27 December 2012, covering China and the surrounding area. Real-time kinematic (RTK) positioning with combined BDS and GPS observations is feasible. Besides, all satellites of BDS can transmit triple-frequency signals. Using the advantages of multi-pseudorange and carrier observations from multi-systems and multi-frequencies is expected to be of much benefit for ambiguity resolution (AR). We propose an integrated AR strategy for medium baselines by using the combined GPS and BDS dual/triple-frequency observations. In the method, firstly the extra-wide-lane (EWL) ambiguities of triple-frequency system, i.e., BDS, are determined first. Then the dual-frequency WL ambiguities of BDS and GPS were resolved with the geometry-based model by using the BDS ambiguity-fixed EWL observations. After that, basic (i.e., L1/L2 or B1/B2) ambiguities of BDS and GPS are estimated together with the so-called ionosphere-constrained model, where the ambiguity-fixed WL observations are added to enhance the model strength. During both of the WL and basic AR, a partial ambiguity fixing (PAF) strategy is adopted to weaken the negative influence of new-rising or low-elevation satellites. Experiments were conducted and presented, in which the GPS/BDS dual/triple-frequency data were collected in Nanjing and Zhengzhou of China, with the baseline distance varying from about 28.6 to 51.9 km. The results indicate that, compared to the single triple-frequency BDS system, the combined system can significantly enhance the AR model strength, and thus improve AR performance for medium baselines with a 75.7% reduction of initialization time on average. Besides, more accurate and stable positioning results can also be derived by using the combined GPS/BDS system.

Hereditary angio-oedema in the Western Cape Province, South Africa

African Journals Online (AJOL)

The parameters reviewed were age, gender, age of diagnosis, duration of ... upper airway, abdominal, external genitalia and limb attacks, respectively. ..... significant differences when analysing by ..... (sports, gardening, tight shoes), emotional.

External Economies Evaluation of Wind Power Engineering Project Based on Analytic Hierarchy Process and Matter-Element Extension Model

Directory of Open Access Journals (Sweden)

Hong-ze Li

2013-01-01

Full Text Available The external economies of wind power engineering project may affect the operational efficiency of wind power enterprises and sustainable development of wind power industry. In order to ensure that the wind power engineering project is constructed and developed in a scientific manner, a reasonable external economies evaluation needs to be performed. Considering the interaction relationship of the evaluation indices and the ambiguity and uncertainty inherent, a hybrid model of external economies evaluation designed to be applied to wind power engineering project was put forward based on the analytic hierarchy process (AHP and matter-element extension model in this paper. The AHP was used to determine the weights of indices, and the matter-element extension model was used to deduce final ranking. Taking a wind power engineering project in Inner Mongolia city as an example, the external economies evaluation is performed by employing this hybrid model. The result shows that the external economies of this wind power engineering project are belonged to the “strongest” level, and “the degree of increasing region GDP,” “the degree of reducing pollution gas emissions,” and “the degree of energy conservation” are the sensitive indices.

Midwestern Millennial University Students' Tolerance for Ambiguity in a Period of Complex World Conflicts

Science.gov (United States)

Mahdi, Ghada S.

2012-01-01

Though age and gender do not affect students' knowledge of global issues and associated ambiguity, the academic major of undergraduates did. Students' combined perceptions on knowledge of these issues and their associated ambiguities varied among the four academic groups of majors. Unlike teacher education majors and in combined other majors…

Context sensitivity and ambiguity in component-based systems design

Energy Technology Data Exchange (ETDEWEB)

Bespalko, S.J.; Sindt, A.

1997-10-01

Designers of components-based, real-time systems need to guarantee to correctness of soft-ware and its output. Complexity of a system, and thus the propensity for error, is best characterized by the number of states a component can encounter. In many cases, large numbers of states arise where the processing is highly dependent on context. In these cases, states are often missed, leading to errors. The following are proposals for compactly specifying system states which allow the factoring of complex components into a control module and a semantic processing module. Further, the need for methods that allow for the explicit representation of ambiguity and uncertainty in the design of components is discussed. Presented herein are examples of real-world problems which are highly context-sensitive or are inherently ambiguous.

Perceptions of racial confrontation: the role of color blindness and comment ambiguity.

Science.gov (United States)

Zou, Linda X; Dickter, Cheryl L

2013-01-01

Because of its emphasis on diminishing race and avoiding racial discourse, color-blind racial ideology has been suggested to have negative consequences for modern day race relations. The current research examined the influence of color blindness and the ambiguity of a prejudiced remark on perceptions of a racial minority group member who confronts the remark. One hundred thirteen White participants responded to a vignette depicting a White character making a prejudiced comment of variable ambiguity, after which a Black target character confronted the comment. Results demonstrated that the target confronter was perceived more negatively and as responding less appropriately by participants high in color blindness, and that this effect was particularly pronounced when participants responded to the ambiguous comment. Implications for the ways in which color blindness, as an accepted norm that is endorsed across legal and educational settings, can facilitate Whites' complicity in racial inequality are discussed.

The association between tolerance for ambiguity and fear of negative evaluation: A study of engineering technology capstone courses

Science.gov (United States)

Dubikovsky, Sergey I.

For many students in engineering and engineering technology programs in the US, senior capstone design courses require students to form a team, define a problem, and find a feasible technical solution to address this problem. Students must integrate the knowledge and skills acquired during their studies at the college or university level. These truly integrative design activities do not have a single "correct" solution. Instead, there is an array of solutions, many of which could be used to achieve the final result. This ambiguity can cause students to experience anxiety during the projects. This study examined the main topics: • To what extent is a social anxiety (measured as fear of negative evaluation) related to tolerance for ambiguity in senior engineering capstone courses? • How does exposure to ambiguity prior to and during capstone courses affect tolerance for ambiguity? The study looked at the standard educational practices to see if they have unintended consequences, such a social anxiety in dealing with ambiguity. Those consequences are highly undesirable because they reduce students' learning. It was hypothesized that the lecture-based approaches that are more common in the first three years of study would not prepare students for self-directed capstone courses because the students would rarely have experienced problem-based learning before. The study used a quantitative approach and examined students' perceptions of their tolerance for ambiguity, and social anxiety before and after their senior capstone design experience. A survey instrument was adapted to measure exposure to ambiguity, which was studied as a potential moderator of the relationship between social anxiety and tolerance for ambiguity. The study indicated that social anxiety, as measured by fear of negative evaluation, does not play a major role in capstone courses. The second finding is that a single course, even if it was administered as a problem-based senior class, failed to

AMBIGUOUS JANUS OF MODERN DEMOCRACY

Directory of Open Access Journals (Sweden)

Volodymyr V. Khmil

2016-06-01

Full Text Available Purpose. The purpose of the research is to analyze ambiguous concept of  democracy as a phenomenon of political and social formation based on political and instrumental approach. As a result, some deep fundamentals of  human social existence and values as social life basis are blurred. Task. The task of  this investigation is to reveal the concept of democracy in its invariative philosophical  meaning and find the consequences of global social transformations towards social entropy. Methods of investigation. To implement the task an activity approach has been used with further possibility to single out two approaches - politological and philosophical. The focus on democracy from philosophic point of view makes possible to anticipate negative entropic processes that lead  to future ambiguity. Subject matter. Chaotic social processes can result in  ruined family, spiritual, legal and moral formations. Regulatory and legal paradigms are becoming less effective and entail disintegration of spiritual and value constituents of worldview causing necessary conditions for social entropy. Originality and Findings. Possible threats for human freedom that hinder the way to targeted  prospects of mankind have been considered in the paper. Thus, taking into account all positive aspects of democracy, it is simultaneously becoming the tool of continuous differentiation of society into tiny autonomous communities similar to nomadic atomization of society. The concept based on moral substantial existence basis as in “axis time” by K. Jaspers that can prevent social entropy resulting in world anthropologic catastrophes has been grounded in the present research.

Simply Imagining Sunshine, Lollipops and Rainbows Will Not Budge the Bias: The Role of Ambiguity in Interpretive Bias Modification.

Science.gov (United States)

Clarke, Patrick J F; Nanthakumar, Shenooka; Notebaert, Lies; Holmes, Emily A; Blackwell, Simon E; Macleod, Colin

2014-01-01

Imagery-based interpretive bias modification (CBM-I) involves repeatedly imagining scenarios that are initially ambiguous before being resolved as either positive or negative in the last word/s. While the presence of such ambiguity is assumed to be important to achieve change in selective interpretation, it is also possible that the act of repeatedly imagining positive or negative events could produce such change in the absence of ambiguity. The present study sought to examine whether the ambiguity in imagery-based CBM-I is necessary to elicit change in interpretive bias, or, if the emotional content of the imagined scenarios is sufficient to produce such change. An imagery-based CBM-I task was delivered to participants in one of four conditions, where the valence of imagined scenarios were either positive or negative, and the ambiguity of the scenario was either present (until the last word/s) or the ambiguity was absent (emotional valence was evident from the start). Results indicate that only those who received scenarios in which the ambiguity was present acquired an interpretive bias consistent with the emotional valence of the scenarios, suggesting that the act of imagining positive or negative events will only influence patterns of interpretation when the emotional ambiguity is a consistent feature.

Placental chorangioma

African Journals Online (AJOL)

Key words: Kano; live birth; placental chorangioma; Pregnancy. Introduction. Placental ... single live intrauterine fetus in longitudinal lie and breech presentation with ... Pelvic examination revealed normal external genitalia; the cervix was ...

Exploring the Relationship between Tolerance of Ambiguity of EFL Learners and Their Vocabulary Knowledge

Science.gov (United States)

Basöz, Tutku

2015-01-01

Learning a new language is akin to exploring an unknown land as ambiguous situations are prevalent in language learning. Ambiguity tolerance, which can hinder or facilitate language learning, is considered as an important learning style. The purpose of the present study was to understand how tolerant/intolerant EFL learners are of foreign language…

Role Ambiguity and Self-Efficacy: The Moderating Effects of Goal Orientation and Procedural Justice

Science.gov (United States)

Li, Andrew; Bagger, Jessica

2008-01-01

The present study investigated variables that moderated the relationship between role ambiguity and self-efficacy. Results of a field study found support for the moderating role of learning goal orientation, such that the relationship between role ambiguity and self-efficacy was weaker when learning goal orientation was high. In addition, we found…

The reciprocal dynamic model of career decision ambiguity tolerance with career indecision: A longitudinal three-wave investigation.

Science.gov (United States)

Xu, Hui; Tracey, Terence J G

2017-10-01

The current study investigated the dynamic interplay of career decision ambiguity tolerance and career indecision over 3 assessment times in a sample of college students (n = 583). While the previous research has repeatedly shown an association of career decision ambiguity tolerance with career indecision, the direction of this association has not been adequately assessed with longitudinal investigation. It was hypothesized in this study that there is a reciprocal pattern of career decision ambiguity tolerance leading to subsequent career indecision and career indecision leading to subsequent career decision ambiguity tolerance. Using a cross-lagged panel design, this study found support for the reciprocal pattern that aversion to ambiguity led to increased negative affect and choice anxiety in career decision making, while negative affect and choice anxiety led to increased aversion to ambiguity. Additionally, this study revealed that aversion led to decreased readiness for career decision making and readiness for career decision making led to increased interests in new information. The key findings were discussed with respect to the theoretical and clinical implications for career counseling along with limitations and suggestions for future research. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Resolution of potential ambiguities through farside angular structure: Semiclassical analysis

International Nuclear Information System (INIS)

Fricke, S.H.; Brandan, M.E.; McVoy, K.W.

1988-01-01

The optical potential fits summarized in the preceding paper are subjected to a semiclassical analysis of the Ford-Wheeler--Knoll-Schaeffer type. The important broad dips in their farside cross sections, which are essential in greatly reducing potential ambiguities, are found (in partial agreement with a suggestion of Goldberg's) to be mainly weak ''Airy'' or rainbow minima, that serve to identify deeply penetrating trajectories. The semiclassical analysis also permits the identification and understanding of a new category of discrete and continuous potential ambiguities, and suggests the manner in which specific features of the angular distributions (such as spacings and depths of various angular minima) determine the Woods-Saxon parameters found by a chi-squared search

Resolving the range ambiguity in OFDR using digital signal processing

International Nuclear Information System (INIS)

Riesen, Nicolas; Lam, Timothy T-Y; Chow, Jong H

2014-01-01

A digitally range-gated variant of optical frequency domain reflectometry is demonstrated which overcomes the beat note ambiguity when sensing beyond a single frequency sweep. The range-gating is achieved using a spread spectrum technique involving time-stamping of the optical signal using high-frequency pseudorandom phase modulation. The reflections from different sections of fiber can then be isolated in the time domain by digitally inverting the phase modulation using appropriately-delayed copies of the pseudorandom noise code. Since the technique overcomes the range ambiguity in OFDR, it permits high sweep repetition rates without sacrificing range, thus allowing for high-bandwidth sensing over long lengths of fiber. This is demonstrated for the case of quasi-distributed sensing. (paper)

Prenatal Diagnosis and Postnatal Ultrasound Findings of Cloacal Anomaly: A Case Report

Directory of Open Access Journals (Sweden)

Lívia Teresa Moreira Rios

2012-01-01

Full Text Available Cloacal malformation is an extremely rare fetal pathological condition that presents as a variety of defects. It predominantly affects females, with prevalence of 1 in 50,000 births. Prenatal ultrasonography on a 20-year-old caucasian woman (G4P1A2 at 33 weeks of pregnancy showed the fetus having a large cystic mass in the lower abdomen with a single septum, bilateral hydronephrosis, ambiguous genitalia, and a single umbilical artery. The pregnancy developed accentuated oligohydramnios, and presence of a fetal brain-sparing effect was diagnosed using arterial Doppler velocimetry. The newborn showed abdominal distension, ambiguous genitalia, and rectal atresia, with a single perineal opening. Pelvic ultrasound done on the first day after delivery revealed the presence of a large retrovesical septated cystic mass of dense content in the fetal abdomen, and bilateral hydronephrosis. Hysterotomy was performed, and 70 mL of dense liquid was drained through an abdominal colostomy. The infant died on the 27th day of life as a result of infectious complications. Prenatal diagnosing of female urogenital anomalies is usually difficult because of their rarity, different types of manifestation, and lack of characteristic ultrasound signs. Presence of a septated cyst with dense content in the fetal abdomen confirms the finding of hydrometrocolpos, thus raising clinical suspicion of a cloacal anomaly.

The ambiguity of US foreign policy towards Africa

DEFF Research Database (Denmark)

Olsen, Gorm Rye

2017-01-01

appear incoherent and ambiguous if judged narrowly on the expectation that it only aims to take care of US national security concerns and economic self-interests. The paper concludes that Africa was important to the United States during the presidencies of George W. Bush and Barack Obama because...

GLONASS CDMA L3 ambiguity resolution and positioning

NARCIS (Netherlands)

Zaminpardaz, Safoora; Teunissen, P.J.G.; Nadarajah, Nandakumaran

2016-01-01

A first assessment of GLONASS CDMA L3 ambiguity resolution and positioning performance is provided. Our analyses are based on GLONASS L3 data from the satellite pair SVNs 755-801, received by two JAVAD receivers at Curtin University, Perth, Australia. In our analyses, four different versions of

Do children exploit the Maxim of Antecedent in order to interpret ambiguous descriptions?

Science.gov (United States)

Surian, L

1991-06-01

Twenty Italian six-year-olds and 20 eight-year-olds were asked to interpret eight ambiguous and eight clear definite descriptions. All ambiguous descriptions could refer to three drawings, one of which had been described by the subjects immediately before the comprehension task. In half of the trials with ambiguous messages the children's interlocutor was present while the children were describing the drawings; in the other half he was absent. In both conditions subjects showed a preference for the referents they had already described, indicating that they applied egocentrically a comprehension strategy based on the Maxim of Antecedent (Jackson & Jacobs, 1982). Children's failures to differentiate their responses in the two conditions are considered to be due to difficulties in taking account of the given-new distinction for relevant information.

Triple-Frequency GPS Precise Point Positioning Ambiguity Resolution Using Dual-Frequency Based IGS Precise Clock Products

Directory of Open Access Journals (Sweden)

Fei Liu

2017-01-01

Full Text Available With the availability of the third civil signal in the Global Positioning System, triple-frequency Precise Point Positioning ambiguity resolution methods have drawn increasing attention due to significantly reduced convergence time. However, the corresponding triple-frequency based precise clock products are not widely available and adopted by applications. Currently, most precise products are generated based on ionosphere-free combination of dual-frequency L1/L2 signals, which however are not consistent with the triple-frequency ionosphere-free carrier-phase measurements, resulting in inaccurate positioning and unstable float ambiguities. In this study, a GPS triple-frequency PPP ambiguity resolution method is developed using the widely used dual-frequency based clock products. In this method, the interfrequency clock biases between the triple-frequency and dual-frequency ionosphere-free carrier-phase measurements are first estimated and then applied to triple-frequency ionosphere-free carrier-phase measurements to obtain stable float ambiguities. After this, the wide-lane L2/L5 and wide-lane L1/L2 integer property of ambiguities are recovered by estimating the satellite fractional cycle biases. A test using a sparse network is conducted to verify the effectiveness of the method. The results show that the ambiguity resolution can be achieved in minutes even tens of seconds and the positioning accuracy is in decimeter level.

"Pinch the Giraffe with the Glove" - Syntactic Ambiguity Resolution in Young Children

OpenAIRE

Young, Amy

2014-01-01

Previous research in language development focusing on the comprehension of ambiguous sentences has found that children are unable to use top-down information, such as referential context, to resolve the ambiguity. The present study aimed to discover whether children were also insensitive to a different form of top-down processing (the prior question). To do so, we conducted an experiment with 5- and 7-year-olds which involved playing with toys on a stage whilst listening to sound files which ...

Strong-coupling study of the Gribov ambiguity in lattice Landau gauge

International Nuclear Information System (INIS)

Maas, Axel; Pawlowski, Jan M.; Spielmann, Daniel; Sternbeck, Andre; Smekal, Lorenz von

2010-01-01

We study the strong-coupling limit β=0 of lattice SU(2) Landau gauge Yang-Mills theory. In this limit the lattice spacing is infinite, and thus all momenta in physical units are infinitesimally small. Hence, the infrared behavior can be assessed at sufficiently large lattice momenta. Our results show that at the lattice volumes used here, the Gribov ambiguity has an enormous effect on the ghost propagator in all dimensions. This underlines the severity of the Gribov problem and calls for refined studies also at finite β. In turn, the gluon propagator only mildly depends on the Gribov ambiguity. (orig.)

The indexing ambiguity in serial femtosecond crystallography (SFX) resolved using an expectation maximization algorithm.

Science.gov (United States)

Liu, Haiguang; Spence, John C H

2014-11-01

Crystallographic auto-indexing algorithms provide crystal orientations and unit-cell parameters and assign Miller indices based on the geometric relations between the Bragg peaks observed in diffraction patterns. However, if the Bravais symmetry is higher than the space-group symmetry, there will be multiple indexing options that are geometrically equivalent, and hence many ways to merge diffraction intensities from protein nanocrystals. Structure factor magnitudes from full reflections are required to resolve this ambiguity but only partial reflections are available from each XFEL shot, which must be merged to obtain full reflections from these 'stills'. To resolve this chicken-and-egg problem, an expectation maximization algorithm is described that iteratively constructs a model from the intensities recorded in the diffraction patterns as the indexing ambiguity is being resolved. The reconstructed model is then used to guide the resolution of the indexing ambiguity as feedback for the next iteration. Using both simulated and experimental data collected at an X-ray laser for photosystem I in the P63 space group (which supports a merohedral twinning indexing ambiguity), the method is validated.

Ongoing neurogenesis in the adult dentate gyrus mediates behavioral responses to ambiguous threat cues.

Directory of Open Access Journals (Sweden)

Lucas R Glover

2017-04-01

Full Text Available Fear learning is highly adaptive if utilized in appropriate situations but can lead to generalized anxiety if applied too widely. A role of predictive cues in inhibiting fear generalization has been suggested by stress and fear learning studies, but the effects of partially predictive cues (ambiguous cues and the neuronal populations responsible for linking the predictive ability of cues and generalization of fear responses are unknown. Here, we show that inhibition of adult neurogenesis in the mouse dentate gyrus decreases hippocampal network activation and reduces defensive behavior to ambiguous threat cues but has neither of these effects if the same negative experience is reliably predicted. Additionally, we find that this ambiguity related to negative events determines their effect on fear generalization, that is, how the events affect future behavior under novel conditions. Both new neurons and glucocorticoid hormones are required for the enhancement of fear generalization following an unpredictably cued threat. Thus, adult neurogenesis plays a central role in the adaptive changes resulting from experience involving unpredictable or ambiguous threat cues, optimizing behavior in novel and uncertain situations.

Simple explanation of the up-down ambiguity in πp and Kπ s-wave phase shifts

International Nuclear Information System (INIS)

Dean, N.W.; Chang, V.

1976-01-01

In both the π + π - and K + π - systems attempts to carry out a phase-shift analysis in the mass region below 1GeV/c 2 have consistently found two distinct solutions. This ''up-down'' ambiguity has been resolved by appealing to additional data and to arguments based on continuity in the energy variable. The letter shown that in both cases the up-down ambiguity is simply the lowest-order Gersten ambiguity, that is, the complex conjugation of the ''Barrelet zero''

Dressed skeleton expansion and the coupling scale ambiguity problem

International Nuclear Information System (INIS)

Lu, Hung Jung.

1992-09-01

Perturbative expansions in quantum field theories are usually expressed in powers of a coupling constant. In principle, the infinite sum of the expansion series is independent of the renormalization scale of the coupling constant. In practice, there is a remnant dependence of the truncated series on the renormalization scale. This scale ambiguity can severely restrict the predictive power of theoretical calculations. The dressed skeleton expansion is developed as a calculational method which avoids the coupling scale ambiguity problem. In this method, physical quantities are expressed as functional expansions in terms of a coupling vertex function. The arguments of the vertex function are given by the physical momenta of each process. These physical momenta effectively replace the unspecified renormalization scale and eliminate the ambiguity problem. This method is applied to various field theoretical models and its main features and limitations are explored. For quantum chromodynamics, an expression for the running coupling constant of the three-gluon vertex is obtained. The effective coupling scale of this vertex is shown to be essentially given by μ 2 ∼ Q min 2 Q med 2 /Q max 2 where Q min 2 Q med 2 /Q max 2 are respectively the smallest, the next-to-smallest and the largest scale among the three gluon virtualities. This functional form suggests that the three-gluon vertex becomes non-perturbative at asymmetric momentum configurations. Implications for four-jet physics is discussed

On the impact of GNSS ambiguity resolution: geometry, ionosphere, time and biases

Science.gov (United States)

Khodabandeh, A.; Teunissen, P. J. G.

2018-06-01

Integer ambiguity resolution (IAR) is the key to fast and precise GNSS positioning and navigation. Next to the positioning parameters, however, there are several other types of GNSS parameters that are of importance for a range of different applications like atmospheric sounding, instrumental calibrations or time transfer. As some of these parameters may still require pseudo-range data for their estimation, their response to IAR may differ significantly. To infer the impact of ambiguity resolution on the parameters, we show how the ambiguity-resolved double-differenced phase data propagate into the GNSS parameter solutions. For that purpose, we introduce a canonical decomposition of the GNSS network model that, through its decoupled and decorrelated nature, provides direct insight into which parameters, or functions thereof, gain from IAR and which do not. Next to this qualitative analysis, we present for the GNSS estimable parameters of geometry, ionosphere, timing and instrumental biases closed-form expressions of their IAR precision gains together with supporting numerical examples.

Anxious and angry rejection sensitivity, social withdrawal, and retribution in high and low ambiguous situations.

Science.gov (United States)

Zimmer-Gembeck, Melanie J; Nesdale, Drew

2013-02-01

Rejection sensitivity (RS) is a tendency to expect, perceive, and overreact to rejection. Our objective was to examine whether anxious and angry RS have specific associations with negative social reactions, and whether responses are intensified in situations of high rejection ambiguity. In two studies, youth (N = 464 and N = 371) reported their RS and anticipated responses to social scenarios. In Study 1, all scenarios portrayed overt rejection events. In Study 2, participants were randomly assigned to conditions portraying overt or ambiguous rejection. Greater rejection expectation was associated with more negative reactions to rejection. Moreover, as expected, anxiety about rejection was uniquely associated with withdrawal, and anger about rejection was uniquely associated with retribution (i.e., reactive aggression). In the second study, RS persons responded more negatively than others to both overt and high ambiguous rejections, but retribution was intensified among participants high in rejection expectation when rejection was ambiguous, and withdrawal was intensified among participants high in anxious RS in overt rejection situations. Consistent with the revised RS model, there are different patterns of emotions, cognitions, and behaviors in response to high and low ambiguous rejection events, which are heightened in youth sensitive to rejection. © 2012, Wiley Periodicals, Inc.

Sublexical Ambiguity Effect in Reading Chinese Disyllabic Compounds

Science.gov (United States)

Huang, Hsu-Wen; Lee, Chia-Ying; Tsai, Jie-Li; Tzeng, Ovid J.-L.

2011-01-01

For Chinese compounds, neighbors can share either both orthographic forms and meanings, or orthographic forms only. In this study, central presentation and visual half-field (VF) presentation methods were used in conjunction with ERP measures to investigate how readers solve the sublexical semantic ambiguity of the first constituent character in…

The ambiguity of simplicity in quantum and classical simulation

Science.gov (United States)

Aghamohammadi, Cina; Mahoney, John R.; Crutchfield, James P.

2017-04-01

A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the ;elegance; of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

Portfolio Management with Stochastic Interest Rates and Inflation Ambiguity

DEFF Research Database (Denmark)

Munk, Claus; Rubtsov, Alexey Vladimirovich

We solve a stock-bond-cash portfolio choice problem for a risk- and ambiguity-averse investor in a setting where the inflation rate and interest rates are stochastic. The expected inflation rate is unobservable, but the investor may learn about it from realized inflation and observed stock and bond...... prices. The investor is aware that his model for the observed inflation is potentially misspecified, and he seeks an investment strategy that maximizes his expected utility from real terminal wealth and is also robust to inflation model misspecification. We solve the corresponding robust Hamilton......-Jacobi-Bellman equation in closed form and derive and illustrate a number of interesting properties of the solution. For example, ambiguity aversion affects the optimal portfolio through the correlation of price level with the stock index, a bond, and the expected inflation rate. Furthermore, unlike other settings...

Pricing risk and ambiguity : The effect of perspective taking

NARCIS (Netherlands)

Trautmann, S.T.; Schmidt, U.

2012-01-01

In the valuation of uncertain prospects, a difference is often observed between selling and buying perspectives. This paper distinguishes between risk (known probabilities) and ambiguity (unknown probabilities) in decisions under uncertainty and shows that the valuation disparity increases under

The impact of uncertain threat on affective bias: Individual differences in response to ambiguity.

Science.gov (United States)

Neta, Maital; Cantelon, Julie; Haga, Zachary; Mahoney, Caroline R; Taylor, Holly A; Davis, F Caroline

2017-12-01

Individuals who operate under highly stressful conditions (e.g., military personnel and first responders) are often faced with the challenge of quickly interpreting ambiguous information in uncertain and threatening environments. When faced with ambiguity, it is likely adaptive to view potentially dangerous stimuli as threatening until contextual information proves otherwise. One laboratory-based paradigm that can be used to simulate uncertain threat is known as threat of shock (TOS), in which participants are told that they might receive mild but unpredictable electric shocks while performing an unrelated task. The uncertainty associated with this potential threat induces a state of emotional arousal that is not overwhelmingly stressful, but has widespread-both adaptive and maladaptive-effects on cognitive and affective function. For example, TOS is thought to enhance aversive processing and abolish positivity bias. Importantly, in certain situations (e.g., when walking home alone at night), this anxiety can promote an adaptive state of heightened vigilance and defense mobilization. In the present study, we used TOS to examine the effects of uncertain threat on valence bias, or the tendency to interpret ambiguous social cues as positive or negative. As predicted, we found that heightened emotional arousal elicited by TOS was associated with an increased tendency to interpret ambiguous cues negatively. Such negative interpretations are likely adaptive in situations in which threat detection is critical for survival and should override an individual's tendency to interpret ambiguity positively in safe contexts. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Clinical and Laboratorial Features That May Differentiate 46,XY DSD due to Partial Androgen Insensitivity and 5 alpha-Reductase Type 2 Deficiency

OpenAIRE

Veiga, NN; Medaets, PAR; Petroli, RJ; Calais, FL; de Mello, MP; Castro, CCTDS; Guaragna, G; Sewaybricker, LE; Marques-de-Faria, AP; Maciel-Guerra, AT; Guerra, G

2012-01-01

The aim of this study was to search for clinical and laboratorial data in 46,XY patients with ambiguous genitalia (AG) and normal testosterone (T) synthesis that could help to distinguish partial androgen insensitivity syndrome (PAIS) from 5-reductase type 2 deficiency (5-RD2) and from cases without molecular defects in the AR and SRD5A2 genes. Fifty-eight patients (51 families) were included. Age at first evaluation, weight and height at birth, consanguinity, familial recurrence, severity of...

Pitfalls in molecular diagnosis of 21-hydroxylase deficiency in congenital adrenal hyperplasia

OpenAIRE

Kolahdouz, Mahsa; Mohammadi, Zahra; Kolahdouz, Parisa; Tajamolian, Masoud; Khanahmad, Hossein

2015-01-01

Congenital adrenal hyperplasia (CAH) is a putative error of metabolism with autosomal recessive heredity pattern. The main manifestations of classic form of CAH are salt-wasting, dehydration and simple virilization in both sexes and ambiguous genitalia in female gender. 21-hyroxylase (CYP21A2) impairment with prevalence value of 1 in 10,000?15,000 live births is the most common etiology of CAH. Because of consanguineous marriages, the frequency of the CAH in Iran is very high. A wide range of...

Children’s and Adolescents’ Processing of Temporary Syntactic Ambiguity: An Eye Movement Study

Directory of Open Access Journals (Sweden)

Paul E. Engelhardt

2014-01-01

Full Text Available This study examined the eye movements of 24 children and adolescents as they read sentences containing temporary syntactic ambiguities. Prior research suggested that children primarily use grammatical information when making initial parsing decisions, and they tend to disregard semantic and contextual information. On each trial, participants read a garden path sentence (e.g., While the storm blew the boat sat in the shed, and, afterwards, they answered a comprehension question (e.g., Did the storm blow the boat?. The design was 2 × 2 (verb type × ambiguity repeated measures. Verb type was optionally transitive or reflexive, and sentences were ambiguous or unambiguous. Results showed no differences in first pass reading times at the disambiguating verb (e.g., sat. However, regressions did show a significant interaction. The unambiguous-reflexive condition had approximately half the number of regressions, suggesting less processing difficulty in this condition. Developmentally, we found that adolescents had significantly better comprehension, which seemed to be linked to the increased tendency to regress from the disambiguating word. Findings are consistent with the assumption that the processing architecture is more restricted in children compared to adolescents. In addition, results indicated that variance in ambiguity resolution was associated with interference control but not working memory.

Ambiguity of the equivalence principle and Hawking's temperature

NARCIS (Netherlands)

Hooft, G. 't

1984-01-01

There are two inequivalent ways in which the laws of physics in a gravitational field can be related to the laws in an inertial frame, when quantum mechanical effects are taken into account. This leads to an ambiguity in the derivation of Hawking's radiation temperature for a black hole: it could be

"What Happened?" Teaching Attribution Theory through Ambiguous Prompts

Science.gov (United States)

McArthur, John

2011-01-01

The concept of attribution, "the act of explaining why something happens or why a person acts a particular way," is typically an abstract concept. This 35-50-minute activity invites students to make a series of attributions by asking them "What happened?" in ambiguous scenes presented in class. Then, students retrospectively identify what…

Participation or pedagogy?: Ambiguities and tensions surrounding the facilitation of children as researchers

OpenAIRE

Kim, Chae-Young

2017-01-01

Ambiguities and tensions can arise when children are facilitated to act as ‘primary researchers’ concerning whether this is primarily to support their ‘participation’ in knowledge production and, with the knowledge produced, in relevant decision-making processes or whether it is mainly for any educational benefits. This article considers these ambiguities and tensions theoretically and by using evidence from a study where English primary school children were supported to conduct their own res...

A New Method for Single-Epoch Ambiguity Resolution with Indoor Pseudolite Positioning.

Science.gov (United States)

Li, Xin; Zhang, Peng; Guo, Jiming; Wang, Jinling; Qiu, Weining

2017-04-21

Ambiguity resolution (AR) is crucial for high-precision indoor pseudolite positioning. Due to the existing characteristics of the pseudolite positioning system, such as the geometry structure of the stationary pseudolite which is consistently invariant, the indoor signal is easy to interrupt and the first order linear truncation error cannot be ignored, and a new AR method based on the idea of the ambiguity function method (AFM) is proposed in this paper. The proposed method is a single-epoch and nonlinear method that is especially well-suited for indoor pseudolite positioning. Considering the very low computational efficiency of conventional AFM, we adopt an improved particle swarm optimization (IPSO) algorithm to search for the best solution in the coordinate domain, and variances of a least squares adjustment is conducted to ensure the reliability of the solving ambiguity. Several experiments, including static and kinematic tests, are conducted to verify the validity of the proposed AR method. Numerical results show that the IPSO significantly improved the computational efficiency of AFM and has a more elaborate search ability compared to the conventional grid searching method. For the indoor pseudolite system, which had an initial approximate coordinate precision better than 0.2 m, the AFM exhibited good performances in both static and kinematic tests. With the corrected ambiguity gained from our proposed method, indoor pseudolite positioning can achieve centimeter-level precision using a low-cost single-frequency software receiver.

MOCCS: Clarifying DNA-binding motif ambiguity using ChIP-Seq data.

Science.gov (United States)

Ozaki, Haruka; Iwasaki, Wataru

2016-08-01

As a key mechanism of gene regulation, transcription factors (TFs) bind to DNA by recognizing specific short sequence patterns that are called DNA-binding motifs. A single TF can accept ambiguity within its DNA-binding motifs, which comprise both canonical (typical) and non-canonical motifs. Clarification of such DNA-binding motif ambiguity is crucial for revealing gene regulatory networks and evaluating mutations in cis-regulatory elements. Although chromatin immunoprecipitation sequencing (ChIP-seq) now provides abundant data on the genomic sequences to which a given TF binds, existing motif discovery methods are unable to directly answer whether a given TF can bind to a specific DNA-binding motif. Here, we report a method for clarifying the DNA-binding motif ambiguity, MOCCS. Given ChIP-Seq data of any TF, MOCCS comprehensively analyzes and describes every k-mer to which that TF binds. Analysis of simulated datasets revealed that MOCCS is applicable to various ChIP-Seq datasets, requiring only a few minutes per dataset. Application to the ENCODE ChIP-Seq datasets proved that MOCCS directly evaluates whether a given TF binds to each DNA-binding motif, even if known position weight matrix models do not provide sufficient information on DNA-binding motif ambiguity. Furthermore, users are not required to provide numerous parameters or background genomic sequence models that are typically unavailable. MOCCS is implemented in Perl and R and is freely available via https://github.com/yuifu/moccs. By complementing existing motif-discovery software, MOCCS will contribute to the basic understanding of how the genome controls diverse cellular processes via DNA-protein interactions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Individual differences in aversion to ambiguity regarding medical tests and treatments: association with cancer screening cognitions.

Science.gov (United States)

Han, Paul K J; Williams, Andrew E; Haskins, Amy; Gutheil, Caitlin; Lucas, F Lee; Klein, William M P; Mazor, Kathleen M

2014-12-01

Aversion to "ambiguity"-uncertainty about the reliability, credibility, or adequacy of information-about medical tests and treatments is an important psychological response that varies among individuals, but little is known about its nature and extent. The purpose of this study was to examine how individual-level ambiguity aversion relates to important health cognitions related to different cancer screening tests. A survey of 1,074 adults, ages 40 to 70 years, was conducted in four integrated U.S. healthcare systems. The Ambiguity Aversion in Medicine (AA-Med) scale, a measure of individual differences in aversion to ambiguity (AA) about medical tests and treatments, was administered along with measures of several cancer screening-related cognitions: perceived benefits and harms of colonoscopy, mammography, and PSA screening, and ambivalence and future intentions regarding these tests. Multivariable analyses were conducted to assess the associations between AA-Med scores and cancer screening cognitions. Individual-level AA as assessed by the AA-Med scale was significantly associated (P ambiguity. Individual-level AA constitutes a measurable, wide-ranging cognitive bias against medical intervention, and more research is needed to elucidate its mechanisms and effects. ©2014 American Association for Cancer Research.

Characterization of an isodicentric Y-chromosome for the long arm in a newborn with mixed gonadal dysgenesis.

Science.gov (United States)

Kohn, B; Kleyman, S M; Conte, R A; Macera, M J; Glassberg, K; Verma, R S

1997-01-01

A newborn infant was referred for evaluation because of ambiguous genitalia. Examination of the genitalia revealed a hypospadiac phallus measuring 1.5 cm in length with chordee. Subtle phenotypic features consistent with Turner syndrome were present including hypertelorism, anti-mongoloid slant to the eyes, mild widening of the neck, but no definitive webbing, shield like chest and positive cubitus valgus. A pelvic and renal sonogram confirmed the presence of a uterus and normal-appearing kidneys. There was incomplete fusion of the scrotum. No gonads were palpable within the scrotal sac. The patient was assigned a female gender on the basis of the presence of a uterus, the phenotypic appearance of the genitalia and the malignant potential of the gonads. The cytogenetic findings with QFQ-banding revealed an abnormal karyotype, i.e., mos 46,X,idic(Y) (p11.2)[77]/45,X[29]/46,X,idic(Y) (p11?) [2]/ 47,XY,idic(Y)(p11.2)[2]/47,X,idic(Y)(p11.2), + idic(Y)(p11.2)[1]/46,XY[1]. The presence of an abnormal isodicentric Y-chromosome was evaluated by FISH-technique to ensure a finer characterization than routine methods. The genotype-phenotype correlation could not be established since mosaicisms of highly variable nature can exhibit an unpredictable outcome.

De novo interstitial deletions of 9q22.1-22.3 in two unrelated cases with different phenotype

Energy Technology Data Exchange (ETDEWEB)

Mohamed, A.N.; Bawle, E.; Conard, J. [Wayne State Univ., Detroit, MI (United States)] [and others

1994-09-01

Deletions involving the long arm of chromosome 9 are rare. A recent review, particularly with deletions of 9q22-32 region, failed to recognize a distinct pattern of dysmorphies and malformations. Herein, we described two phenotypically abnormal unrelated cases with interstitial deletion of chromosome 9 at band q22.1-q22.3. Parents of both cases exhibited normal karyotypes, indicating that the deletions were de novo events. Therefore, the clinical features present in these two cases can be attributed to partial monosomy for the deleted band 9q22. The first case was a 2-day-old baby with ambiguous genitalia, hydrocephalus, cleft palate and lip, polycystic kidney, absence of uterus on ultrasound and one gonad in the labiosacral region. Chromosome analysis showed a male karyotype, 46,XY,del(9)(q22.1q22.3). The absence of monosomy X cell line and the normal histology of testicular tissue were against the diagnosis of mixed gonadal dysgenesis or XY gonadal dysgenesis. The second 3-day-old newborn baby girl presented with right side hypoplastic heart and pulmonary atresia. In addition, the patient showed multiple dysmorphic features including epicanthal fold, low-set ears, depressed nasal bridge, hypertelorism, and micrognathia. The uvula is absent with slight cleft palate. Bilateral clinodactyly of 5th fingers and severe club feet were also present. The external genitalia was of a normal female phenotype. Chromosome study also indicated interstatial deletion of band 9q22. Although both cases appeared to have the same chromosomal anomalies, neither a discrete facial appearance nor a common pattern of malformations was noted.

Analysis of Location Ambiguity, GDOP and Station Layout of Threestation in Multilateration

Directory of Open Access Journals (Sweden)

Xu Zi Li

2016-01-01

Full Text Available In practice, the two-dimensional TDOA source location in the case of three stations would encounter the ambiguity problem of dual solutions. The relationship between distributions of location curve intersections, GDOP and receiving station layout is numerically analyzed, namely the distributions of location curve intersections and GDOP are determined by the receiving station layout, and the areas of two curve intersections are consistent with these of larger GDOP. These analysis results could serve as reference for avoiding or dealing with the ambiguity problem when multilateration is in application.

A new genus and species of Neotropical Nemobiinae (Insecta: Orthoptera: Grylloidea: Trigonidiidae: Nemobiinae).

Science.gov (United States)

Jesus, Fabiene Maria DE; Pereira, Marcelo Ribeiro; Rodrigues, Geanne Carla Ripani; Sperber, Carlos Frankl

2017-06-09

A new genus and a new species of Neotropical cricket is described: Pepoapua cariacica n. gen., n. sp., occurring in four Atlantic Forest remnants in the states of Bahia and Espírito Santo, Brazil. This new genus is morphologically similar in external characteristics, both male and female genitalia, with two other Neotropical genera of Nemobiinae: Amanayara and Kevanemobius. The combination of the external morphological characteristics, along with male genitalia, characterize a new genus through combination of the following characters: (i) males and females with morphologically similar tegmina; (ii) tegmina reduced, not reaching half of the second abdominal segment; (iii) dorsal field of the tegmina with parallel veins, without stridulatory vein or any specialized area for sound production; (iv) tibia of the first pair of legs without tympanum; (v) tibia of the third pair of legs with seven dorsal spurs, four inner and three outer, the proximo-dorsal inner spur reduced in size and the disto-dorsal inner spur without glandular aspect; (vi) ovipositor with distal portion of the dorsal and ventral valves serrated; (vii) male genitalia without evident bristles or sensillas; (viii) pseudepiphallic median lobe presenting apical and ventral projections.

On the robustness and possible accounts of ambiguity aversion

NARCIS (Netherlands)

Keren, G.; Gerritsen, L.E.M.

1999-01-01

Ambiguity aversion is one of the most robust phenomena documented in the decision making literature, though there are still disagreements concerning what constitutes an adequate account for its occurrence. We describe six experiments that shed additional light on the enigmatic phenomenon of

The Development of Preschoolers' Appreciation of Communicative Ambiguity

Science.gov (United States)

Nilsen, Elizabeth S.; Graham, Susan A.

2012-01-01

Using a longitudinal design, preschoolers' appreciation of a listener's knowledge of the location of a hidden sticker after the listener was provided with an ambiguous or unambiguous description was assessed. Preschoolers (N = 34) were tested at 3 time points, each 6 months apart (4, 4 1/2, and 5 years). Eye gaze measures demonstrated that…

Genetics Home Reference: CHARGE syndrome

Science.gov (United States)

... syndrome are often born with an unusually small penis (micropenis) and undescended testes (cryptorchidism). Abnormalities of external genitalia are seen less often in affected females. Puberty can be incomplete or delayed in affected males ...

Ambiguity in the Acquisition of Lexical Information

OpenAIRE

Vanderwende, Lucy

1995-01-01

This paper describes an approach to the automatic identification of lexical information in on-line dictionaries. This approach uses bootstrapping techniques, specifically so that ambiguity in the dictionary text can be treated properly. This approach consists of processing an on-line dictionary multiple times, each time refining the lexical information previously acquired and identifying new lexical information. The strength of this approach is that lexical information can be acquired from de...

Ambiguity and uncertainty tolerance, need for cognition, and their association with stress. A study among Italian practicing physicians.

Science.gov (United States)

Iannello, Paola; Mottini, Anna; Tirelli, Simone; Riva, Silvia; Antonietti, Alessandro

2017-01-01

Medical practice is inherently ambiguous and uncertain. The physicians' ability to tolerate ambiguity and uncertainty has been proved to have a great impact on clinical practice. The primary aim of the present study was to test the hypothesis that higher degree of physicians' ambiguity and uncertainty intolerance and higher need for cognitive closure will predict higher work stress. Two hundred and twelve physicians (mean age = 42.94 years; SD = 10.72) from different medical specialties with different levels of expertise were administered a set of questionnaires measuring perceived levels of work-related stress, individual ability to tolerate ambiguity, stress deriving from uncertainty, and personal need for cognitive closure. A linear regression analysis was performed to examine which variables predict the perceived level of stress. The regression model was statistically significant [R 2  = .32; F(10,206) = 8.78, p ≤ .001], thus showing that, after controlling for gender and medical specialty, ambiguity and uncertainty tolerance, decisiveness (a dimension included in need for closure), and the years of practice were significant predictors of perceived work-related stress. Findings from the present study have some implications for medical education. Given the great impact that the individual ability to tolerate ambiguity and uncertainty has on the physicians' level of perceived work-related stress, it would be worth paying particular attention to such a skill in medical education settings. It would be crucial to introduce or to empower educational tools and strategies that could increase medical students' ability to tolerate ambiguity and uncertainty. JSQ: Job stress questionnaire; NFCS: Need for cognitive closure scale; PRU: Physicians' reactions to uncertainty; TFA: Tolerance for ambiguity.

Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

Directory of Open Access Journals (Sweden)

Maria Paula Roncaglia-Denissen

Full Text Available In the current event-related potential (ERP study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first. Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

Speech rhythm facilitates syntactic ambiguity resolution: ERP evidence.

Science.gov (United States)

Roncaglia-Denissen, Maria Paula; Schmidt-Kassow, Maren; Kotz, Sonja A

2013-01-01

In the current event-related potential (ERP) study, we investigated how speech rhythm impacts speech segmentation and facilitates the resolution of syntactic ambiguities in auditory sentence processing. Participants listened to syntactically ambiguous German subject- and object-first sentences that were spoken with either regular or irregular speech rhythm. Rhythmicity was established by a constant metric pattern of three unstressed syllables between two stressed ones that created rhythmic groups of constant size. Accuracy rates in a comprehension task revealed that participants understood rhythmically regular sentences better than rhythmically irregular ones. Furthermore, the mean amplitude of the P600 component was reduced in response to object-first sentences only when embedded in rhythmically regular but not rhythmically irregular context. This P600 reduction indicates facilitated processing of sentence structure possibly due to a decrease in processing costs for the less-preferred structure (object-first). Our data suggest an early and continuous use of rhythm by the syntactic parser and support language processing models assuming an interactive and incremental use of linguistic information during language processing.

Implementation ambiguity: The fifth element long lost in uncertainty budgets for land biogeochemical modeling

Science.gov (United States)

Tang, J.; Riley, W. J.

2015-12-01

Previous studies have identified four major sources of predictive uncertainty in modeling land biogeochemical (BGC) processes: (1) imperfect initial conditions (e.g., assumption of preindustrial equilibrium); (2) imperfect boundary conditions (e.g., climate forcing data); (3) parameterization (type I equifinality); and (4) model structure (type II equifinality). As if that were not enough to cause substantial sleep loss in modelers, we propose here a fifth element of uncertainty that results from implementation ambiguity that occurs when the model's mathematical description is translated into computational code. We demonstrate the implementation ambiguity using the example of nitrogen down regulation, a necessary process in modeling carbon-climate feedbacks. We show that, depending on common land BGC model interpretations of the governing equations for mineral nitrogen, there are three different implementations of nitrogen down regulation. We coded these three implementations in the ACME land model (ALM), and explored how they lead to different preindustrial and contemporary land biogeochemical states and fluxes. We also show how this implementation ambiguity can lead to different carbon-climate feedback estimates across the RCP scenarios. We conclude by suggesting how to avoid such implementation ambiguity in ESM BGC models.

Practical ambiguities during calculation of energy ratios and their impacts on life cycle assessment calculations

International Nuclear Information System (INIS)

Zhang, Yongli; Colosi, Lisa M.

2013-01-01

The energy ratio metrics are increasingly important means of assessing the efficiency of energy production for emerging biofuels platforms, making comparisons among multiple alternatives, and formulating policies to foster commercialization of sustainable energy systems. However, these metrics are susceptible to inadvertent or meaningful mathematical manipulation, whereby the same dataset can be used to compute dramatically different values of energy return on investment (EROI). In this study, previously published life cycle assessment (LCA) data for algal biofuels, corn ethanol, and switchgrass ethanol are used to demonstrate how seven seemingly reasonable EROI formulations give rise to a wide range of output values. It is then demonstrated that production of bioelectricity, and to a lesser extent, other co-products, significantly increases EROI ambiguity. Overall, the EROI results are used to illustrate how EROI ambiguity makes it difficult to properly assess the energetic favorability of a particular energy system or to make accurate comparisons among multiple systems. It is then recommended that all future biofuels studies restrict themselves to usage of “EROI 1 ”, which documents all input and outputs as explicit terms, to mitigate EROI ambiguity and improve policy decision-making. - Highlights: ► Energy ratios are appealing but potentially ambiguous sustainability metrics. ► Various ratio formulations can give different metrics for the same dataset. ► Production of electricity or other co-products exacerbates ratio ambiguity