335 research outputs found
Microlocal spectrum condition and Hadamard form for vector-valued quantum fields in curved spacetime
Some years ago, Radzikowski has found a characterization of Hadamard states
for scalar quantum fields on a four-dimensional globally hyperbolic spacetime
in terms of a specific form of the wavefront set of their two-point functions
(termed `wavefront set spectrum condition'), thereby initiating a major
progress in the understanding of Hadamard states and the further development of
quantum field theory in curved spacetime. In the present work, we extend this
important result on the equivalence of the wavefront set spectrum condition
with the Hadamard condition from scalar fields to vector fields (sections in a
vector bundle) which are subject to a wave-equation and are quantized so as to
fulfill the covariant canonical commutation relations, or which obey a Dirac
equation and are quantized according to the covariant anti-commutation
relations, in any globally hyperbolic spacetime having dimension three or
higher. In proving this result, a gap which is present in the published proof
for the scalar field case will be removed. Moreover we determine the
short-distance scaling limits of Hadamard states for vector-bundle valued
fields, finding them to coincide with the corresponding flat-space, massless
vacuum states.Comment: latex2e, 41 page
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Hidden Complications of Thought Suppression
Although the suppression of thoughts may seem to be an effective solution, this strategy can lead to an exacerbation of the very thought that one is attempting to suppress. This ironic effect is the most obvious unwanted outcome of suppression and has now been investigated empirically for more than two decades. However, the fact that suppression is an effortful process implies that, even when suppression does not lead to an ironic rebound of the unwanted thought, it puts an insidious cognitive load on the individual attempting to suppress. Moreover, whether or not suppression leads to an exacerbation of the unwanted thought, it is rarely successful, and hence adds to the individual's distress. In this article we describe the phenomenon of suppression and consider how it might complicate a range of emotional disorders. Taken together, studies on thought suppression in psychopathology present a more nuanced picture now than was emerging in the early years of its investigation. Some evidence is consistent with the idea that the counterproductive effects of suppression are causally implicated in the disorder, but for the most part a more parsimonious conclusion is that thought suppression acts as a complication of the disorder. In certain disorders, suppression complicates the disorder by leading to an ironic rebound of the unwanted thoughts. In all disorders, the cost of undertaking suppression is a persistent cognitive load, which, in turn undermines the ability to suppress, and hence sets off a cycle of failed expectations and distress.Psycholog
Effect of enriched rotifer (Brachionus plicatilis) with probiotic lactobacilli on growth, survival and resistance indicators of western white shrimp (Litopenaeus vannamei) larvae
This study examined the effects of a commercial Lactobacillus probiotic on growth, survival and resistance of western white shrimp (Litopenaeus vannamei) larvae against salinity and formalin stresses in the Persian Gulf and Oman Sea Ecology Research Center. In this experiment, larvae were fed 6 times a day from mysis I (M1) step to post larvae 5 over 3 treatments including a control treatment C (without probiotic) and 2 experimental treatments namely A (having probiotic enriched rotifer) and B (having probiotic enriched rotifer and adding probiotic powder directly to the water). Larvae were stocked in 9 plastic tanks (20-liter) containing 10 L of seawater at a density of 50 larvae per liter. Three replicates were used for each treatment. At the end of the experimental period biometric larvae were studied under salinity and formalin stresses. Results showed that using probiotic bacteria had significant and positive effects on shrimp resistance, survival and growth (p0.05). According to the results we may conclude that the use of probiotic powder is effective in increasing growth, survival and resistance rate of western white shrimp in the larval and post larval stages
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Managing Unwanted Intrusive Thoughts In Obsessive Compulsive Disorder: Relative Effectiveness Of Suppression, Focused-Distraction, and Acceptance
Suppression is one of various mental control techniques that people may use to manage unwanted thoughts. Evidence suggests that it is at best unsustainable and at worst counterproductive. This leads to the question: If suppression is a futile way to respond to unwanted, intrusive, thoughts, what is a more effective alternative? In the current study, we evaluated the relative effectiveness of suppression and two alternative mental control techniques—focused distraction and acceptance—on the frequency of intrusions and distress associated with them. Results support the claim that suppression is a counterproductive technique for dealing with unwanted, intrusive thoughts in OCD. However, the harmfulness of suppression was reflected primarily in the magnitude of distress and not in intrusion frequency. Focused distraction and acceptance were the more effective techniques for managing clinically significant intrusive thoughts. We discuss implications for the cognitive treatment for OCD.Psycholog
Gaya Belajar dan Kreatifitas Mahasiswa Program Studi Manajemen Pendidikan Islam
Dewasa ini gaya belajar dapat menjadi permasalahan urgent pada setiap mahasiswa maka sangat diperlukan kreatifitas dalam meningkatkan minat belajar agar meningkat pula sistem pendidikan di Indonesia. Dalam penelitian ini peneliti menawarkan desain penelitian menggunakan pendekatan kuantitatif menggunakan metode survei. Penelitian yang dilakukan di IAIN Bukittinggi ini melibatkan 44 mahasiswa dengan instrumen penelitian yaitu mengumpulkan data berupa angket dengan skala likert. Penelitian dianalisis menggunakan statistik deskriptif dan inferensial. Statistik deskriptif terdiri dari nilai min, standar deviasi, persentase dan frekuensi. Sedangkan statistik inferensial melibatkan penggunaan teknik statistik MANOVA dan Korelasi Pearson. Adapun hasil dari penelitian ini ialah tingkat gaya belajar kompetitif, menghindar dan bebas berada pada level tinggi, sedangkan gaya belajar kolaboratif berada pada level rendah. Serta kreatifitas keaslian, kelenturan dan kelancaran mahasiswa berada pada tahap yang dominan atau tinggi. Tes MANOVA menunjukkan tidak ada perbedaan yang signifikan jenis gaya belajar dan kreatifitas mahasiswa berdasarkan gender. Namu pada analisis korelasi Pearson menunjukkan bahwa ada hubungan yang signifikan antara gaya belajar dan kreatifitas mahasiswa. Penelitian seperti ini diharapkan dapat dilakukan dari waktu ke waktu sesuai dengan kebutuhan guna mengetahui perubahan gaya belajar dan kreativitas mahasiswa seperti dapat mengaitkan dengan variabel lain di antaranya gaya belajar, strategi belajar dan prestasi akademik, karakteristik kepribadian dan prestasi akademik,. Ketiga variabel tersebut tidak dibahas dalam penelitian ini. Padahal, akan sangat bermanfaat bagi mahasiswa jika ketiga variabel ini dipelajari dan diidentifikasi penyebabny
Diagnosis of premature rupture of membranes by the detection of thyroid hormones in vaginal secretions
Background: Premature rupture of membranes (PROM) and preterm PROM (PPROM) are the rupture of the fetal chorioamniotic membranes before the onset of labor contractions. Objectives: To evaluate whether detection of thyroid hormones in vaginal washouts can be used to diagnose premature rupture of membranes (PROM). Patients and Methods: Total T4 (thyroxin), total T3 (triiodothyronine), and free T4 concentrations in vaginal washouts were analyzed in 45 women with the diagnosis of PROM and compared with 45 normal pregnancies (controls). A Student�s t-test was used for comparison of thyroid hormone values and a ROC curve was used for analyzing the diagnostic accuracy Results: There were no differences between the patients with PROM and the control women regarding maternal age, gestational age, and parity. The mean concentration of total T4 in the PROM group and the control subjects were 2.1 ± 1.3 jig/mL and 1.55 ± 0.58 jig/, respectively (P = 0.01). Total T3 concentration in the PROM group was significantly higher compared to the controls (1.28 ± 0.42 ng/ vs. 0.8 ± 0.26 ng/, P < 0.0001). Also, free T4 concentration was significantly higher in the PROM group as compared with the controls (0.026 ± 0.034 ng/ vs.0.007 ± 0.004 ng/, P < 0.0001). The ROC curve analysis showed that total T4=1.685 jig/ had a sensitivity of 62, specificity of 76, positive predictive value (PPV) of 71.8, and negative predictive value (NPV) of 66.7. Total T3 = 0.82 ng/ gave a sensitivity of 91, specificity of 64, PPV of 72, and NPV of 87.8. Free T4 = 0.01 ng/ gave a sensitivity of 51, specificity of 82, PPV of 74.2, and NPV of 62.7. The best cutoff values were total T4 = 1.685 ng/, total T3 = 0.82 ng/, and free T4 = 0.01 ng/. Conclusions: Detecting total T4, total T3, and free T4 in vaginal washouts of patients suspected of PROM suspected is a simple, available, rapid, and inexpensive method for the diagnosis of PROM. However, a combination of three tests is recommended. © 2015, Shiraz University of Medical Sciences
Study of Prevalence of Martin-Gruber Anomaly in Patients with Carpal Tunnel Syndrome
Median-Ulnar connection in the forearm, also known as the Martin-Gruber communication (MGC), is a common anatomic nerve anomaly with the incidence from 5% to 34% in the normal population. Knowledge of this anomaly is of crucial importance in evaluation of injuries of Median and Ulnar nerves; as well as in accurate interpretation of the nerve conduction velocity of these nerves. This study aimed at evaluating the frequency of martin - Gruber communication and its common types in patients with Carpal Tunnel Syndrome (CTS). 151 patients with definite diagnosed Carpal Tunnel Syndrome by electro-diagnostic method (123 females and 28 males with the mean age of 46.42+/_11.21 years) were enrolled in the study over a 13 months period. 19 patients (12.6 %) -13 females, 6 males-had MGC. In 285 upper extremities with carpal tunnel syndrome, 25 (8.8%) cases had martin - Gruber communication. Types 1, 2 and 3 of this anomaly were seen in 7 (43.8%), 14 (87.5%), 6 (37.5%) patients respectively. In our study the prevalence of Martin - Gruber connection in the patients with carpal tunnel syndrome was within the same range as in literature, however lower than the mean reported value. MGC Type 2 was the most common type in patients with CTS
Coral Reef Ecosystem Management in Area of Eastern Coastal Water Conservation Weh Island Sabang
Coral reef ecosystem is important for coastal resources.Damage of Coral reefs resulted in de-gradation of population and fishes reef diversity. The East coast ofWeh Island in Sabang designated as conversation area that has aim to keep coral reefs from destructive utilization activites.The purpose of this study was to know the status of coral reefecosystemsmanagement in marine protected areaEast CoastWeh Island, Sabang and to analyze theattributessensitivelyfromthedimension ofecological,socio-economicand institutional sector.The methodthat used toknow the statusof the sustainablemanagementis RAPFISHanalysis.Dimensions oftheecologycan be known by measuring the coral growth used thePointInterceptTransect,reef fishabundanceusedUnderwaterVisualCensusFishmethod.Socio-economicand institutionaldimensionswill be collected through Focus Group Discussion(FGD) and help by questionnaires.Management status of coral reef ecosystems in the region of the East coast Weh islandmultidimensionallyindicatesthat it was quitesustainable.The most sensitiveattributeofthe managementisthe growth ofsaplings ofcorals,reef fishabundance,conflicts betweenfishermen,the public perceptionagainstthe abundance of fish, the role of the community, and the fishingmanagements
Continuity of symplectically adjoint maps and the algebraic structure of Hadamard vacuum representations for quantum fields on curved spacetime
We derive for a pair of operators on a symplectic space which are adjoints of
each other with respect to the symplectic form (that is, they are sympletically
adjoint) that, if they are bounded for some scalar product on the symplectic
space dominating the symplectic form, then they are bounded with respect to a
one-parametric family of scalar products canonically associated with the
initially given one, among them being its ``purification''. As a typical
example we consider a scalar field on a globally hyperbolic spacetime governed
by the Klein-Gordon equation; the classical system is described by a symplectic
space and the temporal evolution by symplectomorphisms (which are
symplectically adjoint to their inverses). A natural scalar product is that
inducing the classical energy norm, and an application of the above result
yields that its ``purification'' induces on the one-particle space of the
quantized system a topology which coincides with that given by the two-point
functions of quasifree Hadamard states. These findings will be shown to lead to
new results concerning the structure of the local (von Neumann)
observable-algebras in representations of quasifree Hadamard states of the
Klein-Gordon field in an arbitrary globally hyperbolic spacetime, such as local
definiteness, local primarity and Haag-duality (and also split- and type
III_1-properties). A brief review of this circle of notions, as well as of
properties of Hadamard states, forms part of the article.Comment: 42 pages, LaTeX. The Def. 3.3 was incomplete and this has been
corrected. Several misprints have been removed. All results and proofs remain
unchange
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