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1.
Phys Rev Lett ; 130(12): 122502, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027859

RESUMEN

The excited states of N=44 ^{74}Zn were investigated via γ-ray spectroscopy following ^{74}Cu ß decay. By exploiting γ-γ angular correlation analysis, the 2_{2}^{+}, 3_{1}^{+}, 0_{2}^{+}, and 2_{3}^{+} states in ^{74}Zn were firmly established. The γ-ray branching and E2/M1 mixing ratios for transitions deexciting the 2_{2}^{+}, 3_{1}^{+}, and 2_{3}^{+} states were measured, allowing for the extraction of relative B(E2) values. In particular, the 2_{3}^{+}→0_{2}^{+} and 2_{3}^{+}→4_{1}^{+} transitions were observed for the first time. The results show excellent agreement with new microscopic large-scale shell-model calculations, and are discussed in terms of underlying shapes, as well as the role of neutron excitations across the N=40 gap. Enhanced axial shape asymmetry (triaxiality) is suggested to characterize ^{74}Zn in its ground state. Furthermore, an excited K=0 band with a significantly larger softness in its shape is identified. A shore of the N=40 "island of inversion" appears to manifest above Z=26, previously thought as its northern limit in the chart of the nuclides.

2.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36332266

RESUMEN

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

3.
Phys Rev Lett ; 118(7): 072701, 2017 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-28256889

RESUMEN

The ß-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of ß-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.

4.
Soc Incl ; 11(1): 60-71, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-37674610

RESUMEN

The Narratives of Neurodiversity Network (NNN) is a neurodivergent academic, creative, and educator collective that came together with allies during the Covid-19 pandemic to create a network centred around emerging narratives about neurodiversity and exploring new ways of learning and socialising. The network focuses on exploring the roles of written, spoken, and visual narratives across cultural locations about neuro-atypical experiences in generating improved agency and self-advocacy for those who have been subject to pathologization through neuro-normativity and intersecting oppression. During the last year, widening access to digital platforms has provided a space to explore these issues outside of traditional academic spaces. We run a monthly "Salon," our mixed-media "reading, listening, and watching" group, in an effort to find positive representation within contemporary culture. Discussions have moved beyond mimesis and into a consideration of how narrative and storyworlds can question the supposed naturalness of certain ways of being in and perceiving the world. This article interrogates the network's core principles of nonhierarchical co-production, including the roles of creativity, community, identity, and emancipatory research which were animated by the new techno-social context. We consider the cultural lives of neurodiversity in the West and beyond, including ethical and aesthetic dimensions. We share a faith in the power of storytelling to inform new social identities for neurodivergent people and to inform scientific understandings of atypical cognition. In exploring this, we speak through a porous first-person plural narrator, to unsettle the idea that there is a hegemonic "we" speaking on behalf of all neurodivergent people.

5.
Aust Dent J ; 24(1): 26-33, 1979 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-375902

RESUMEN

The results of twenty patients treated for the maxillo-septal syndrome and associated temporomandibular joint dysfunction are reported as well as the method of treatment. The treatment plan included rapid maxillary expansion with either a fixed or removable appliance, retention of the increased maxillary width with a Hawley retainer, simultaneous increase in mandibular width with a Crozat appliance. Finally the occlusion was equilibrated. Certain cases are discussed in detail and maxillary expansion was usually restricted to between 1 . 0 and 2 . 0 mm.


Asunto(s)
Maloclusión/complicaciones , Maxilar/anomalías , Tabique Nasal/anomalías , Síndrome de la Disfunción de Articulación Temporomandibular/etiología , Adolescente , Adulto , Niño , Oclusión Dental Balanceada , Femenino , Humanos , Masculino , Maloclusión/terapia , Aparatos Ortodóncicos , Técnica de Expansión Palatina , Síndrome de la Disfunción de Articulación Temporomandibular/terapia
6.
Aust Dent J ; 25(5): 284-94, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6936006

RESUMEN

In oral lichen planus two types of lymphocytes were found in the lamina propria in the basal and suprabasal layers. The T-cell is identified by the absence of rough-surfaced endoplasmic reticulum in contrast to its extensive development in the B-cell of which various types were identified including plasma cells. Interaction was noted between macrophages, lymphocytes, and epithelial cells. The variability noted in T-cells may arise from sensitization related to phagocytosis of degenerate epithelial cells by macrophages which transfer the immunological information to lymphocytes.


Asunto(s)
Mucosa Bucal/ultraestructura , Epitelio/ultraestructura , Humanos , Liquen Plano/patología , Linfocitos/ultraestructura , Macrófagos/ultraestructura , Mastocitos/ultraestructura , Enfermedades de la Boca/patología , Células Plasmáticas/ultraestructura
7.
Aust Dent J ; 23(2): 171-7, 1978 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-361027

RESUMEN

Seventy-three pre-medieval British skulls were examined and the maxillo-septal syndrome was found in 42. Ten foetal specimens of crown rump length greater than 40 mm were also examined and the syndrome was found in three specimens. Deflection of the nasal septum was present in 56 specimens.


Asunto(s)
Feto/patología , Maxilar/anomalías , Tabique Nasal/anomalías , Paleopatología , Adolescente , Adulto , Estudios Transversales , Femenino , Historia Antigua , Humanos , Incisivo/anomalías , Masculino , Persona de Mediana Edad , Síndrome , Reino Unido
8.
Aust Dent J ; 27(3): 176-88, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6958233

RESUMEN

The present report is concerned with the immunopathogenesis of recurrent aphthous ulcers (RAU). Lymphocytes in various stages of sensitization are described and their interaction with macrophages, each other and epithelial cells. Typical macrophages were seen in the lamina propria but not in affected epithelium. The phagocytic cells seen between epithelial cells and in the juxtabasal part of the lamina propria was identified as a reticuloid cell because of close connections with each other, numerous microvesicles and electron-lucent (euchromatic) nuclei. It is thought that it replaces the macrophage seen in Behçet's syndrome and oral lichen planus and is responsible for the localized nature of RAU.


Asunto(s)
Estomatitis Aftosa/patología , Epitelio/ultraestructura , Humanos , Linfocitos/ultraestructura , Macrófagos/ultraestructura , Microscopía Electrónica , Mucosa Bucal/ultraestructura , Recurrencia , Estomatitis Aftosa/inmunología
9.
Aust Dent J ; 26(1): 31-41, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6972758

RESUMEN

The purpose of the present study was to classify lymphocytes in the buccal mucosa of patients affected with recurrent apthous ulceration. Two lymphocytes were identified. The B lymphocyte was characterized by an extensive Golgi complex, an extensive tubular rough surfaced endoplasmic reticulum, and an extensive canalicular system. Usually the nucleus was electron lucent except for perinuclear condensation of chromatin. The T lymphocyte had a moderately developed Golgi complex, absent or poorly developed rough surfaced endoplasmic reticulum, lysosomes, and considerably more heterochromatin (perinuclear) than the B lymphocyte. Uropods were associated with the T lymphocyte and exerted cytotoxic effects on basal and suprabasal cells.


Asunto(s)
Linfocitos B/ultraestructura , Mucosa Bucal/patología , Estomatitis Aftosa/patología , Linfocitos T/ultraestructura , Adulto , Membrana Celular/ultraestructura , Núcleo Celular/ultraestructura , Retículo Endoplásmico/ultraestructura , Femenino , Aparato de Golgi/ultraestructura , Humanos , Masculino , Persona de Mediana Edad , Recurrencia
10.
Aust Dent J ; 26(5): 311-20, 1981 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6949533

RESUMEN

The results of treatment of 67 patients with septo-maxillary syndrome and associated temporomandibular joint dysfunction are reported. Five case histories are described in detail. The features of the syndrome emphasized are the maxillo-septal facies, ipsilateral deficiency of facial mesenchyme (mesectoderm) and condylar displacement. Associated with condylar displacement was early osteo-arthritis of the temporomandibular joint complex. It is suggested that Costen's syndrome needs restatement.


Asunto(s)
Anomalías Maxilomandibulares/terapia , Tabique Nasal/anomalías , Síndrome de la Disfunción de Articulación Temporomandibular/terapia , Asimetría Facial , Femenino , Humanos , Masculino , Maloclusión/etiología , Maloclusión/terapia , Cóndilo Mandibular/anomalías , Radiografía Panorámica , Síndrome , Síndrome de la Disfunción de Articulación Temporomandibular/complicaciones
11.
Aust Dent J ; 20(2): 78-85, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1057897

RESUMEN

The human temporomandibular joint in transverse and longitudinal section was found to have two types of mechanoreceptors. One of capsular form approximately 40 times 200 mum innervated by myelinated nerve fibres 8 mum in diameter and the other corresponding to the Golgi tendon organ was innervated by myelinated nerve fibers 15 mum in diameter which on entering the tendon organ lost their myelin sheaths.


Asunto(s)
Mecanorreceptores/anatomía & histología , Articulación Temporomandibular/inervación , Tejido Adiposo/anatomía & histología , Corpúsculos de Golgi-Mazzoni/anatomía & histología , Humanos , Ligamentos Articulares/inervación , Músculos Masticadores/inervación , Fibras Nerviosas Mielínicas , Articulación Temporomandibular/ultraestructura , Tendones/inervación
12.
Aust Dent J ; 20(4): 214-20, 1975 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1058662

RESUMEN

Electromyograms were compared with kinematograms recorded for 35 male dental students, average age 25 years, with full occlusions and without temporomandibular joint dysfunction. The records were obtained during the open-close-clench cycle rhythmically performed as the patient occluded on the molar teeth. The mechanical tracings disclosed seven subjects with centric slide and the duration of the cycle was significantly longer than normal. The kinematographic latency of the jaw opening reflex was found to be about equal to the sum of the electromyographic latency and inhibition.


Asunto(s)
Mandíbula/fisiología , Reflejo , Potenciales de Acción , Adulto , Oclusión Dental Céntrica , Electromiografía , Humanos , Masculino , Músculos Masticadores/fisiología , Diente Molar/fisiología , Películas Cinematográficas , Movimiento , Factores de Tiempo
13.
Aust Dent J ; 25(1): 12-9, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6929182

RESUMEN

Seven cases of the erosive type of lichen planus, as well as normal tissue, were studied with the optical and electron microscope. The study was concerned with the distribution and formation of colloid bodies. These bodies were located at the epithelial-proprial junctions and occasionally inter-epithelially. They were seldom larger than basal epithelial cells and were macrophages which contained fragments of phagocytosed epithelial cells. They probably correspond to cytoid bodies which have a similar size and a similar distribution.


Asunto(s)
Gránulos Citoplasmáticos/ultraestructura , Liquen Plano/patología , Mucosa Bucal/ultraestructura , Anciano , Mejilla , Células Epiteliales , Epitelio/ultraestructura , Femenino , Humanos , Inmunoglobulina M , Macrófagos/ultraestructura , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Enfermedades de la Boca/patología , Mucosa Bucal/citología , Reacción del Ácido Peryódico de Schiff , Estomatitis Aftosa/patología
14.
Aust Dent J ; 25(2): 93-100, 1980 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6156669

RESUMEN

Superficial, transitional and polygonal buccal epithelial cells from patients with the erosive type of lichen planus were compared with similar cells from non-keratinizing human buccal mucosa. Transitional cells from non-keratinizing buccal mucosa had glycogen lakes and membrane-coating granules with electron dense cores. Surface cells were not keratinized and pathological cells were less granular. In lichen planus membrane-coating granules were numerous, markedly electron dense, and some showed an internal lamellar structure. Surface cells were keratotic or parakeratotic. Processes of macrophages were associated with the pathological membrane-coating granules.


Asunto(s)
Liquen Plano/patología , Mucosa Bucal/ultraestructura , Gránulos Citoplasmáticos/ultraestructura , Epitelio/patología , Epitelio/ultraestructura , Encía/ultraestructura , Glucógeno/metabolismo , Membranas Intracelulares/ultraestructura , Queratinas/metabolismo , Microscopía Electrónica , Enfermedades de la Boca/patología , Organoides/ultraestructura
15.
Aust Dent J ; 24(2): 94-106, 1979 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-380538

RESUMEN

Three hundred and forty-eight cranial remains from Bronze and Iron Age British, Romano-British, Anglo-Saxon, Eastern Coast Australian aborigines, Medieval Christian Norse, Medieval Scarborough, 17--20th century British and German cultures, were examined for the presence of osteoarthritis in the temporomandibular joints. Cultures exposed to more stringent living conditions and with well-worn teeth had about twice the incidence of osteo-arthritis as the more sophisticated cultures. In general, loss of either molar support or occlusal imbalance were potent aetiological factors in this disease.


Asunto(s)
Cultura , Osteoartritis/historia , Articulación Temporomandibular , Adolescente , Adulto , Resorción Ósea/fisiopatología , Alemania , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia Antigua , Historia Medieval , Humanos , Maloclusión/complicaciones , Cóndilo Mandibular/patología , Persona de Mediana Edad , Osteoartritis/epidemiología , Osteoartritis/etiología , Osteoartritis/patología , Osteoartritis/fisiopatología , Osteogénesis , Articulación Temporomandibular/patología , Articulación Temporomandibular/fisiopatología , Abrasión de los Dientes/complicaciones , Abrasión de los Dientes/patología , Reino Unido
16.
Aust Dent J ; 23(6): 480-7, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-285670

RESUMEN

Electromyographic analysis was carried out prior to occlusal equilibration for patients who had some form of TMJ dysfunction and again after treatment. The results were compared with similar analyses for patients without any symptoms of dysfunction (controls) and for patients who had been wearing some kind of occlusal appliance as treatment for dysfunction. The parameters measured were the period of minimal activity (inactive phase of jaw elevators sometimes referred to as the inactive phase), the duration of muscle contraction before tooth contact (DMC), the period of muscle activity after tooth contact (latency), the inhibitory response, and the duration of the clench phase of the temporal and masseter muscles. In general the pathological series had longer cycles, longer DMC, longer clench phases and less significant correlation coefficients than the controls. The results indicated a dominance of the closing muscles in the pathological groups over the other parameters of the cycle during metronome monitoring. Also, the controls and the POST equilibration group yielded readily to cortical command. The parameters of the cycle in the POST-equilibration group were facilitated as compared to the other groups.


Asunto(s)
Electromiografía , Músculos Masticadores/fisiología , Reflejo/fisiología , Síndrome de la Disfunción de Articulación Temporomandibular/terapia , Adulto , Mentón , Oclusión Dental , Oclusión Dental Balanceada , Femenino , Humanos , Masculino , Contracción Muscular , Percusión , Férulas (Fijadores) , Síndrome de la Disfunción de Articulación Temporomandibular/fisiopatología , Factores de Tiempo
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