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3.
Anim Cogn ; 25(5): 1331-1343, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35430682

RESUMEN

Environmental condition, such as environmental complexity or stocking density, can directly or indirectly influence animal emotion and ultimately, affective state. Affective states of animals can be assessed through judgement bias tests, evaluating responses to ambiguous situations. In this study, we aimed to determine whether environmental complexity and stocking density impacted rainbow trout affective state. Rainbow trout (n = 108) were housed in recirculating aquaculture systems under commercial conditions while trained at tank-level to discriminate between a positively reinforced chamber (feed) in one location and a negative chamber (positive punishment; chase by net for 1 s) in the opposing location. Fish from successful tanks (two out of five tanks) were then housed in treatment tanks of either high- or low- environmental complexity at either high (165 fish/m3) or low (69 fish/m3) stocking density. Trained fish were tested for latencies to approach three intermediate, ambiguous chambers. Fish housed in high-density tanks were faster to enter all chambers than those housed in low-density tanks (8.5 s vs. 15.2 s; P = 0.001), with faster entries into the positive (7.4 s vs. 15.2 s; P = 0.02) and near-negative chambers (10.2 s vs. 17.4 s; P = 0.006), suggesting that these fish were more optimistic to receive a feed reward. Tank complexity did not affect test outcomes. No differences between treatments were observed between body weight, length, and plasma cortisol. Overall, rainbow trout are capable of discriminating between cues during a judgement bias test and fish housed in high-density environments respond more optimistically in ambiguous situations compared to fish in low-density environments.


Asunto(s)
Oncorhynchus mykiss , Animales , Oncorhynchus mykiss/fisiología , Acuicultura , Emociones
4.
Artículo en Inglés | MEDLINE | ID: mdl-31092952

RESUMEN

Technologies such as BigData, Cloud, Grid, and IoT are reshaping current data systems and practices, and IT experts are just as keen on harnessing the power of distributed systems to boost security and prevent fraud. How can massive distributed system capabilities be used to improve processing, instead of inflating risk?

5.
Artículo en Inglés | MEDLINE | ID: mdl-31092953

RESUMEN

Cryptographic hash functions are security-critical algorithms with many practical applications, notably in digital signatures. Developing an approach to test them can be particularly difficult, and bugs can remain unnoticed for many years. We revisit the NIST hash function competition, which was used to develop the SHA-3 standard, and apply a new testing strategy to all available reference implementations. Motivated by the cryptographic properties that a hash function should satisfy, we develop four tests. The Bit-Contribution Test checks if changes in the message affect the hash value, and the Bit-Exclusion Test checks that changes beyond the last message bit leave the hash value unchanged. We develop the Update Test to verify that messages are processed correctly in chunks, and then use combinatorial testing methods to reduce the test set size by several orders of magnitude while retaining the same fault-detection capability. Our tests detect bugs in 41 of the 86 reference implementations submitted to the SHA-3 competition, including the rediscovery of a bug in all submitted implementations of the SHA-3 finalist BLAKE. This bug remained undiscovered for seven years, and is particularly serious because it provides a simple strategy to modify the message without changing the hash value returned by the implementation. We detect these bugs using a fully-automated testing approach.

7.
J Synchrotron Radiat ; 23(Pt 5): 1158-70, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27577771

RESUMEN

A comprehensive investigation of the emission characteristics for electrons induced by X-rays of a few hundred eV at grazing-incidence angles on an atomically clean Cu(111) sample during laser excitation is presented. Electron energy spectra due to intense infrared laser irradiation are investigated at the BESSY II slicing facility. Furthermore, the influence of the corresponding high degree of target excitation (high peak current of photoemission) on the properties of Auger and photoelectrons liberated by a probe X-ray beam is investigated in time-resolved pump and probe measurements. Strong electron energy shifts have been found and assigned to space-charge acceleration. The variation of the shift with laser power and electron energy is investigated and discussed on the basis of experimental as well as new theoretical results.

8.
HNO ; 64(6): 435-44, 2016 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-27240793

RESUMEN

The laryngeal adductor reflex and the pharyngoglottal closure reflex protect the trachea and lower respiratory tract against the entrance of foreign material. The laryngeal expiration reflex and the cough reflex serve to propel foreign material, which has penetrated in the cranial direction. The inspiration reflex, the sniff reflex, and the swallowing reflex are further larynx-associated reflexes. In patients with dysphagia the laryngeal adductor reflex can be clinically tested with air pulses. The water swallow test serves to show the integrity of the cough reflex. The sniff reflex is useful to test the abduction function of the vocal folds. Future studies should address laryngeal reflexes more specifically, both for a better understanding of these life-supporting mechanisms and to improve diagnostic procedures in patients with impaired laryngeal function.


Asunto(s)
Técnicas de Diagnóstico del Sistema Digestivo , Enfermedades de la Laringe/diagnóstico , Enfermedades de la Laringe/fisiopatología , Laringe/fisiopatología , Reflejo Anormal/fisiología , Humanos
9.
HNO ; 64(4): 271-83; quiz 284-5, 2016 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-27038033

RESUMEN

Despite normal hearing thresholds in pure tone audiometry, 0.5-1 % of children have difficulty understanding what they hear. An auditory processing disorder (APD) can be assumed, which should be clarified and treated. Based on a selective literature search in the PubMed and Scopus databases using the term "auditory processing disorder", several consensus papers are discussed. Numerous studies on APD have revealed partially contradicting results, thus fueling critical discussion regarding validity and reliability-of specific audiometric APD methods and the APD construct in particular. In order to correctly advise parents and, where necessary, treat affected children, otorhinolaryngologists, phoniatrists, and pediatric audiologists must understand the psychometric properties of applied tests and have knowledge of current discussion. Diagnosis is generally a multistep interdisciplinary process.


Asunto(s)
Audiometría/métodos , Audiometría/psicología , Trastornos de la Percepción Auditiva/diagnóstico , Trastornos de la Percepción Auditiva/psicología , Psicometría/métodos , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Alemania , Humanos , Lactante , Recién Nacido , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Clin Exp Immunol ; 184(3): 389-402, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26800118

RESUMEN

Allogeneic stem cell transplantation is potentially curative, but associated with post-transplantation complications, including cytomegalovirus (CMV) infections. An effective immune response requires T cells recognizing CMV epitopes via their T cell receptors (TCRs). Little is known about the TCR repertoire, in particular the TCR-α repertoire and its clinical relevance in patients following stem cell transplantation. Using next-generation sequencing we examined the TCR-α repertoire of CD8(+) T cells and CMV-specific CD8(+) T cells in four patients. Additionally, we performed single-cell TCR-αß sequencing of CMV-specific CD8(+) T cells. The TCR-α composition of human leucocyte antigen (HLA)-A*0201 CMVpp65- and CMVIE -specific T cells was oligoclonal and defined by few dominant clonotypes. Frequencies of single clonotypes reached up to 11% of all CD8(+) T cells and half of the total CD8(+) T cell repertoire was dominated by few CMV-reactive clonotypes. Some TCR-α clonotypes were shared between patients. Gene expression of the circulating CMV-specific CD8(+) T cells was consistent with chronically activated effector memory T cells. The CD8(+) T cell response to CMV reactivation resulted in an expansion of a few TCR-α clonotypes to dominate the CD8(+) repertoires. These results warrant further larger studies to define the ability of oligoclonally expanded T cell clones to achieve an effective anti-viral T cell response in this setting.


Asunto(s)
Antígenos Virales/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Epítopos/inmunología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología , Anciano , Secuencia de Aminoácidos , Antígenos Virales/genética , Linfocitos T CD8-positivos/patología , Linfocitos T CD8-positivos/virología , Células Clonales , Citomegalovirus/crecimiento & desarrollo , Infecciones por Citomegalovirus/etiología , Infecciones por Citomegalovirus/genética , Infecciones por Citomegalovirus/virología , Epítopos/genética , Femenino , Regulación de la Expresión Génica , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Humanos , Memoria Inmunológica , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/terapia , Leucemia Mieloide Aguda/inmunología , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/terapia , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Análisis de Secuencia de ADN , Transducción de Señal , Análisis de la Célula Individual , Trasplante Homólogo
11.
Innov Syst Softw Eng ; 12(4): 249-261, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28133442

RESUMEN

A key issue in testing is how many tests are needed for a required level of coverage or fault detection. Estimates are often based on error rates in initial testing, or on code coverage. For example, tests may be run until a desired level of statement or branch coverage is achieved. Combinatorial methods present an opportunity for a different approach to estimating required test set size, using characteristics of the test set. This paper describes methods for estimating the coverage of, and ability to detect, t-way interaction faults of a test set based on a covering array. We also develop a connection between (static) combinatorial coverage and (dynamic) code coverage, such that if a specific condition is satisfied, 100% branch coverage is assured. Using these results, we propose practical recommendations for using combinatorial coverage in specifying test requirements.

12.
Nervenarzt ; 86(8): 997-1006, 2015 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-26215144

RESUMEN

BACKGROUND: Patients with myotonic dystrophy (MD) are known to suffer from oropharyngeal dysphagia and esophageal motility disorders, which are often the cause of aspiration pneumonia. So far only little is known about the pharyngeal contractility and the function of the upper esophageal sphincter in these patients, in particular only few data are available for manometric investigations allowing assessment of the pharyngeal pressure build-up during swallowing. The aim of this study was to collect such data in patients with MD using high resolution manometry. METHOD: In two patients with MD high resolution manometry studies were performed during swallowing and phonation to determine pressure-dependent parameters. The results were compared with normal values from healthy subjects. RESULTS: In both patients a reduced pressure in the entire pharynx during swallowing was determined. The duration of the contraction in the velopharynx and tongue base region was shortened. The structural course of the swallowing process and the opening and closing functions of the upper esophageal sphincter were regular. During realization of closed vowels a reduced pressure build-up in the velopharyngeal region was observed. CONCLUSION: The force of contraction and the associated pharyngeal pressure build-up during swallowing were reduced resulting in an incomplete clearing of the pharynx. Beside myopathic disorders, neuromuscular disorders also have to be considered. The functional course of the swallowing process and the swallowing pattern was retained. The reduced pressure build-up in the velopharyngeal region can be considered as the cause for rhinophonia. To evaluate the pharyngeal function in patients with MD, high resolution manometry is a useful tool for assessing the pharyngeal function besides the basic diagnostics.


Asunto(s)
Trastornos de Deglución/fisiopatología , Deglución , Manometría/métodos , Distrofia Miotónica/fisiopatología , Músculos Faríngeos/fisiopatología , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Muscular , Distrofia Miotónica/complicaciones , Distrofia Miotónica/diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
HNO ; 63(7): 504-10, 2015 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-26148562

RESUMEN

As a highly differentiated physiological process, swallowing may be affected by a variety of confounding factors. Primarily described are swallowing disorders caused by mechanical anatomic changes (e. g., alteration of the cervical spine, goiter), surgery for head and neck tumors, thyroid abnormalities, and neuromuscular disorders. Age-related cerebral neurological and blood vessel-associated changes can also cause dysphagia (so-called presbyphagia) or worsen the condition.Medication-associated dysphagia is recognized far less frequently, not paid due attention, or accepted in silence; particularly in older patients. Furthermore, pharmacological interference of different medications is frequently inadequately considered, particularly in the case of polypharmacy.Initial treatment of medication-induced dysphagia includes a critical review of medication status, with the aim of reducing/discontinuing the causative medication by giving precise instructions regarding its administration; as well as antacid medication, diet, and professional oral stimulation or swallowing training.To date, medication-induced dysphagia has not occupied the focus of physicians and therapists. This is despite the fact that many active agents can have a negative effect on swallowing and medication-induced dysphagia caused by polypharmacy is not uncommon, particularly in old age. This article presents an overview of the different classes of drugs in terms of their direct or indirect negative effects on the swallowing function.


Asunto(s)
Trastornos de Deglución/inducido químicamente , Trastornos de Deglución/prevención & control , Deglución/efectos de los fármacos , Administración Oral , Trastornos de Deglución/diagnóstico , Humanos
14.
Clin Immunol ; 160(2): 282-5, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26111479

RESUMEN

Children born by Caesarean Section have a higher risk for type 1 diabetes. We aimed to investigate whether Caesarean Section leads to alterations of the immune response in children with familial risk for type 1 diabetes. We examined measures of innate and adaptive immune responses in 94 prospectively followed children, including 40 born by Caesarean Section. Proinflammatory serum cytokine concentrations were determined at age 6 months. As a measure of vaccine response, IgG1, IgG2, and IgG4 tetanus antibody titers and CD4(+) T cell proliferation against tetanus toxoid were quantified. Compared to infants born by vaginal delivery, infants born by Caesarean Section had lower concentrations of the cytokines IFN-É£ (p=0.014) and IL-8 (p=0.005), and weaker CD4(+) T cell responses to tetanus measured in the first (p=0.007) and second year (p=0.047) of life. Overall, our findings provide evidence that the mode of delivery influences the immune status and responsiveness during childhood.


Asunto(s)
Inmunidad Adaptativa/inmunología , Cesárea , Diabetes Mellitus Tipo 1/inmunología , Interferón gamma/inmunología , Interleucina-8/inmunología , Toxoide Tetánico/inmunología , Anticuerpos Antibacterianos/inmunología , Linfocitos T CD4-Positivos , Estudios de Casos y Controles , Parto Obstétrico , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/genética , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Humanos , Inmunoglobulina G , Lactante , Interleucina-10/inmunología , Interleucina-12/inmunología , Interleucina-1beta/inmunología , Interleucina-2/inmunología , Interleucina-6/inmunología , Masculino , Estudios Prospectivos , Toxina Tetánica/inmunología , Factor de Necrosis Tumoral alfa/inmunología
15.
Science ; 347(6225): 978-82, 2015 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-25722407

RESUMEN

Femtosecond x-ray laser pulses are used to probe the carbon monoxide (CO) oxidation reaction on ruthenium (Ru) initiated by an optical laser pulse. On a time scale of a few hundred femtoseconds, the optical laser pulse excites motions of CO and oxygen (O) on the surface, allowing the reactants to collide, and, with a transient close to a picosecond (ps), new electronic states appear in the O K-edge x-ray absorption spectrum. Density functional theory calculations indicate that these result from changes in the adsorption site and bond formation between CO and O with a distribution of OC-O bond lengths close to the transition state (TS). After 1 ps, 10% of the CO populate the TS region, which is consistent with predictions based on a quantum oscillator model.

16.
J Mater Chem B ; 3(9): 1760-1768, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-32262249

RESUMEN

Silver compounds and nanoparticles (NPs) are gaining increasing interest in medical applications, specifically in the treatment and prevention of biomaterial-related infections. However, the silver release from these materials, resulting in a limited antimicrobial activity, is often difficult to control. In this paper, ceria nanocontainers were synthesized by a template-assisted method and were then used to encapsulate silver nitrate (AgNO3/CeO2 nanocontainers). Over the first 30 days, a significant level of silver was released, as determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). A novel type of ceria container containing silver NPs (AgNP/CeO2 containers) was also developed using two different template removal methods. The presence of AgNPs was confirmed both on the surface and in the interior of the ceria containers by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Upon removal of the template by calcination, the silver was released over a period exceeding three months (>90 days). However, when the template was removed by dissolution, the silver release was shortened to ≤14 days. The antimicrobial activity of the silver-containing CeO2 containers was observed and the minimum bactericidal concentration (MBC) was determined using the broth dilution method. Investigation on human cells, using a model epithelial barrier cell type (A549 cells), highlighted that all three samples induced a heightened cytotoxicity leading to cell death when exposed to all containers in their raw form. This was attributed to the surface roughness of the CeO2 nanocontainers and the kinetics of the silver release from the AgNO3/CeO2 and AgNP/CeO2 nanocontainers. In conclusion, despite the need for further emphasis on their biocompatibility, the concept of the AgNP/CeO2 nanocontainers offers a potentially alternative long-term antibactericidal strategy for implant materials.

17.
HNO ; 62(9): 640-3, 2014 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-25103988

RESUMEN

BACKGROUND: Otolaryngologists caring for patients with hearing and balance disorders are also responsible for advising patients about their increased risk of falling and informing them of fall prevention measures. This review will give a brief overview of appropriate programs. METHODS: This systematic review is based on a selective literature search. RESULTS: Intrinsic and extrinsic fall risk factors can be distinguished. The former include not only hearing and balance disorders, but also increasing age, nocturia, dementia, limited mobility and poor nutritional status. Extrinsic factors include, for example, unfixed carpet edges, poor lighting and poor footwear. Fall prevention can be achieved through appropriate counselling about risk factors and fall prevention courses. DISCUSSION: The frequency of falls--with potentially very adverse consequences--increases continuously beyond the age of 60 years. Furthermore, the risk of falling is significantly increased in patients with hearing and balance disorders. Otolaryngologists caring for this patient group should inform them about their fall risk and advise appropriate countermeasures during counselling. A basal knowledge of fall prevention measures is therefore helpful.


Asunto(s)
Accidentes por Caídas/prevención & control , Consejo Dirigido/métodos , Trastornos de la Audición/terapia , Educación del Paciente como Asunto/métodos , Conducta de Reducción del Riesgo , Enfermedades Vestibulares/terapia , Anciano , Anciano de 80 o más Años , Femenino , Trastornos de la Audición/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vestibulares/diagnóstico
18.
Genes Brain Behav ; 13(7): 579-91, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25077934

RESUMEN

Maternal care is an indispensable component of offspring survival and development in all mammals and necessary for reproductive success. Although brain areas regulating maternal behaviors are innervated by serotonergic afferents, very little is known about the role of this neurotransmitter in these behaviors. To evaluate the contribution of serotonin to maternal care, we used mice with a null mutation in the gene for tryptophan hydroxylase-2 (TPH2), which results in a genetic depletion of brain serotonin, and tested them in a wide range of maternal behavior paradigms. We found that litters born to and reared by TPH2(-/-) mothers showed decreased survival, lower weaning weights and increased cannibalization. In addition, TPH2(-/-) mothers performed poorly in pup retrieval, huddling, nest construction and high-arched back nursing. Aggression in TPH2(-/-) dams was not triggered by lactation and was steadily high. Survival and weaning weight deficits of TPH2(-/-) pups were rescued by cross-fostering and in litters of mixed genotype (TPH2(-/-) and TPH2(-/+) ). However, the maternal behaviors of TPH2(-/-) dams did not improve when rearing either TPH2(+/+) pups or mixed-genotype litters. In addition, TPH2(-/-) pups significantly worsened the behavior of TPH2(+/+) dams with respect to cannibalism, weaning weight and latency to attack. Olfactory and auditory functions of TPH2(-/-) females or anxiety-like behaviors did not account for these maternal alterations as they were equal to their TPH2(+/+) counterparts. These findings illustrate a profound influence of brain serotonin on virtually all elements of maternal behavior and establish that TPH2(-/-) pups can engender maladaptive mothering in dams of both genotypes.


Asunto(s)
Encéfalo/metabolismo , Conducta Materna , Serotonina/metabolismo , Triptófano Hidroxilasa/metabolismo , Animales , Animales Recién Nacidos/fisiología , Femenino , Genotipo , Masculino , Ratones , Ratones Endogámicos C57BL , Delgadez , Triptófano Hidroxilasa/genética
19.
HNO ; 62(9): 654-60, 2014 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-25135373

RESUMEN

BACKGROUND: The requirement for otorhinolaryngologists and phoniatricians to diagnose dysphagia and evaluate its extent is on the rise, particularly in light of demographic changes. The gold standards in confirmatory diagnostics are fiberoptic endoscopic evaluation of swallowing (FEES) and the videofluoroscopic swallowing examination (VFS). Standardized assessments, such as questionnaires or assessments involving probatory swallows are often applied as screening or supportive measures. This article aims to give a critical overview of the assessment tools frequently used in clinical routine. Test quality is assessed, particularly compared to FEES and VFS. METHODS: A selective literature search using PubMed has been conducted. RESULTS: On the basis of this lierature search, 48 assessment tools were identified. These can be classified into screening tools, instrument-based tools (implementation standards and evaluation protocols) and questionnaire-based assessment inventories. DISCUSSION: In order to diagnose and evaluate dysphagia on the basis of assessment critieria, clinicians should be aware of indications for, as well as the advantages, disadvantages and test quality of the assessment tools. Considering the different assessment tools for anamnesis and probatory swallowing, rather low sensitivities and specificities for possible penetration and aspiration are evident. In cases where these symptoms of dysphagia are not evident and reliably assessable, confirmatory assessment via FEES or VFS is essential.


Asunto(s)
Trastornos de Deglución/diagnóstico , Trastornos de Deglución/psicología , Autoevaluación Diagnóstica , Tamizaje Masivo/métodos , Calidad de Vida/psicología , Encuestas y Cuestionarios , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
HNO ; 62(9): 644-51, 2014 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-25008270

RESUMEN

Disturbances of the swallowing process can occur at any age and might lead to choking. However, the risk of dysphagia increases with advanced age. This is not only due to a higher incidence of diseases that cause dysphagia, but also to age-related changes in the mechanisms of swallowing. Aging affects all of the anatomic structures involved in the swallowing process. Important changes include limitations to mastication, delayed triggering of the swallowing reflex, expansion of pharyngeal structures, prolonged pharyngeal propulsion, loss of pharyngeal sensitivity, increased rigidity of the esophageal wall and reduced esophageal contractility. Changes in swallowing function caused by aging alone are termed presbyphagia. If these changes are so severe that their compensation is no longer possible, presbydysphagia occurs. For diagnostic and therapeutic purposes it is mandatory to evaluate presbyphagic and presbydysphagic changes in the swallowing process, and to distinguish these from other non-age-related causes of dysphagia.


Asunto(s)
Trastornos de Deglución/diagnóstico , Trastornos de Deglución/terapia , Evaluación Geriátrica/métodos , Anciano , Anciano de 80 o más Años , Trastornos de Deglución/fisiopatología , Femenino , Humanos , Masculino
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