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1.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065179

RESUMEN

Understanding the behaviors of materials in their operating and manufacturing environments is essential not only in the scientific field, but also in the context of designing industrial materials for target applications. In this study, we developed a high-temperature x-ray diffraction (XRD) system, using a small microscope heating stage at the BL02B2 beamline in SPring-8. Newly designed sample cells composed of sapphire single crystals were employed to perform XRD experiments using powdered samples at high temperatures and under oxidization/reduction gas atmospheres, with a short sample exchange time. More specifically, XRD experiments were conducted under vacuum, air, inert gas (maximum temperature: ∼1400 °C), and reduction gas flow conditions (maximum temperature: ∼900 °C). In addition, to monitor the changes in the exhausted gas composition during the chemical reactions, the developed heating system was combined with in situ gas-analysis tools (a remote gas-pressure control system, gas chromatograph, and mass spectrometer), which allowed analysis of the gas-adsorption/desorption and solid-gas reaction processes. Several heating experiments, such as the observation of the reduction of Fe oxides, phase transitions of ZrO2 and BaCO3, and synthesis of BaZrO3, demonstrated the validity and usefulness of this system.

2.
Sci Rep ; 12(1): 21657, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36522382

RESUMEN

Two-dimensional (2D) triangular lattice antiferromagnets (2D-TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2-dimensional transition metal dichalcogenide LiCrTe[Formula: see text], being a 2D-TLA, enriched the range of materials which can present such properties. In this work, muon spin rotation ([Formula: see text]SR) and neutron powder diffraction (NPD) have been utilized to reveal the true magnetic nature and ground state of LiCrTe[Formula: see text]. From high-resolution NPD the magnetic spin order at base-temperature is not, as previously suggested, helical, but rather collinear antiferromagnetic (AFM) with ferromagnetic (FM) spin coupling within the ab-plane and AFM coupling along the c-axis. The value if the ordered magnetic Cr moment is established as [Formula: see text]. From detailed [Formula: see text]SR measurements we observe an AFM ordering temperature [Formula: see text] K. This value is remarkably higher than the one previously reported by magnetic bulk measurements. From [Formula: see text]SR we are able to extract the magnetic order parameter, whose critical exponent allows us to categorize LiCrTe[Formula: see text] in the 3D Heisenberg AFM universality class. Finally, by combining our magnetic studies with high-resolution synchrotron X-ray diffraction (XRD), we find a clear coupling between the nuclear and magnetic spin lattices. This suggests the possibility for a strong magnon-phonon coupling, similar to what has been previously observed in the closely related compound LiCrO[Formula: see text].

3.
Minim Invasive Neurosurg ; 54(3): 142-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21863525

RESUMEN

BACKGROUND: Lumbar foraminal stenosis is a troublesome disease. Decompression of the whole length of the nerve root from the spinal canal to extraforaminal zone is often a surgical requirement due to the difficulty in identifying the nerve compression site before surgery, making preservation of the posterior elements difficult. The authors report a minimally invasive microendoscopic technique for lumbar foraminal stenosis to decompress the entire length of the nerve root from the spinal canal to the extraforaminal zone while preserving the posterior elements. SURGICAL PROCEDURE: A tubular retractor is inserted towards the base of the transverse process of the upper vertebra with the retractor tilted inward at a 45-degree angle or greater. Approximately one-third of the pedicle is resected caudally from the base of the transverse process to the spinal canal. After identification of the nerve root, compression factors around the nerve are excised from the spinal canal to the extraforaminal zone without damaging posterior elements such as the facet joints and pars interarticularis. RESULTS: We treated 6 patients with lumbar foraminal stenosis using this procedure. There were no complications during the operation, and satisfactory results were obtained in all cases. CONCLUSIONS: This microendoscopic technique proved to be useful for the treatment of lumbar foraminal stenosis.


Asunto(s)
Descompresión Quirúrgica/métodos , Vértebras Lumbares/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Neuroendoscopía/métodos , Radiculopatía/cirugía , Estenosis Espinal/cirugía , Anciano , Descompresión Quirúrgica/instrumentación , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/patología , Masculino , Microscopía/instrumentación , Microscopía/métodos , Microcirugia/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Neuroendoscopía/instrumentación , Radiculopatía/patología , Radiculopatía/fisiopatología , Radiografía , Estenosis Espinal/patología , Estenosis Espinal/fisiopatología
5.
Br J Cancer ; 101(8): 1425-32, 2009 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-19826427

RESUMEN

BACKGROUND: Several human cancers have been found to contain cancer stem-like cells (CSCs) having cancer-initiating ability. However, only a few reports have shown the existence of CSCs in bone and soft tissue sarcomas. In this study, we identified and characterised side population (SP) cells that showed drug-resistant features in human bone sarcoma cell lines. METHODS: In seven osteosarcoma cell lines (OS2000, KIKU, NY, Huo9, HOS, U2OS and Saos2) and in one bone malignant fibrous histiocytoma (MFH) cell line (MFH2003), the frequency of SP cells was analysed. Tumourigenicity of SP cells was assessed in vitro and in vivo. Gene profiles of SP cells and other populations (main population; MP) of cells were characterised using cDNA microarrays. RESULTS: SP cells were found in NY (0.31%) and MFH2003 (5.28%). SP cells of MFH2003 formed spherical colonies and re-populated into SP and MP cells. In an NOD/SCID mice xenograft model, 1 x 10(3) sorted SP cell-induced tumourigenesis. cDNA microarray analysis showed that 23 genes were upregulated in SP cells. CONCLUSIONS: We showed that SP cells existed in bone sarcoma cell lines. SP cells of MFH2003 had cancer-initiating ability in vitro and in vivo. The gene profiles of SP cells could serve as candidate markers for CSCs in bone sarcomas.


Asunto(s)
Neoplasias Óseas/patología , Células Madre Neoplásicas/patología , Osteosarcoma/patología , Animales , Línea Celular Tumoral , Humanos , Ratones , Ratones SCID
6.
Kyobu Geka ; 62(13): 1140-3, 2009 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-19999091

RESUMEN

A 64-year-old man underwent coronary artery bypass grafting (CABG) in 1994. Eleven years later, coronary angiography (CAG) showed a saphenous vein graft (SVG) aneurysm. In April 2008, the CAG demonstrated enlargement of the aneurysm. Enhanced computed tomography showed a large aneurysm measuring 53 x 44 mm in diameter of the SVG-right coronary artery (RCA) [#3] anastomosis. Off-pump coronary surgery to RCA and aneurysmectomy was planned through a median epigastric incision. However re-grafting was difficult because of severe adhesion and calcification of the coronary artery. We confirmed sufficient back flow from the distal coronary artery without hemodynamic and electrocardiographic changes under SVG clamp. Aneurysmectomy was then performed without coronary bypass. The patient was discharged 9 days after surgery and has been well for 8 months in outpatient clinic.


Asunto(s)
Aneurisma/etiología , Puente de Arteria Coronaria , Vena Safena , Aneurisma/cirugía , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias
7.
Nat Commun ; 10(1): 5340, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31745095

RESUMEN

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

8.
Nat Commun ; 10(1): 4742, 2019 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-31628346

RESUMEN

Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins - but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean's largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval Antarctic krill.


Asunto(s)
Biomasa , Euphausiacea/fisiología , Cadena Alimentaria , Spheniscidae/fisiología , Ballenas/fisiología , Animales , Regiones Antárticas , Carbono/metabolismo , Ciclo del Carbono , Euphausiacea/crecimiento & desarrollo , Agua de Mar/química
9.
Neuron ; 27(2): 339-47, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10985353

RESUMEN

At inhibitory synapses on a cerebellar Purkinje neuron, the depolarization caused by heterosynaptic climbing fiber activation induces long-lasting potentiation accompanied by an increase in GABA(A) receptor responsiveness. Here we show that activation of a presynaptic inhibitory interneuron during the conditioning postsynaptic depolarization suppresses the potentiation. The suppression is due to postsynaptic GABA(B) receptor activation by GABA released from presynaptic terminals. The results suggest that GABA(B) receptor activation decreases the activity of cAMP-dependent protein kinase through the G(i)/G(o) proteins. The presynaptic activity-dependent suppression of synaptic plasticity is a novel regulatory mechanism of synaptic efficacy at individual synapses and may contribute to the learning and computational ability of the cerebellar cortex.


Asunto(s)
Inhibición Neural/fisiología , Células de Purkinje/metabolismo , Receptores de GABA-B/metabolismo , Transmisión Sináptica/fisiología , Animales , Calcio/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , AMP Cíclico/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Dendritas/efectos de los fármacos , Dendritas/metabolismo , Estimulación Eléctrica , Agonistas del GABA/farmacología , Agonistas de Receptores GABA-B , Antagonistas de Receptores de GABA-B , Proteínas de Unión al GTP/metabolismo , Interneuronas/citología , Interneuronas/metabolismo , Iontoforesis , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Plasticidad Neuronal/fisiología , Técnicas de Placa-Clamp , Terminales Presinápticos/metabolismo , Células de Purkinje/citología , Ratas , Ratas Wistar , Receptores de GABA-A/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Ácido gamma-Aminobutírico/farmacología
10.
Neuroscience ; 155(1): 90-103, 2008 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-18571867

RESUMEN

Following transection of the spinal cord, severed axonal ends retract from the lesion site and attempt regeneration within 24 h of injury. Molecular mechanisms underlying such rapid axonal reactions after severance are not fully characterized so far. To better understand the early axonal degenerating and regenerating processes, we examined the immunohistological expression of axonal cytoskeletal proteins from 5 min to 48 h after scalpel-transection of adult rat spinal cord white matter. Within 30 min of transection, expression of neurofilament (NF)- and peripherin-like immunoreactivity (-IR) was enhanced in severed axonal ends, which conversely lost beta-III-tubulin-IR expression, indicating differential expression of beta-III-tubulin-IR and NF/peripherin-IR. During the next few hours, the strongly-NF/peripherin-IR-positive severed axonal ends adhered to each other and these cytoskeletal alterations expanded bi-directionally (rostro-caudally) 100-300 microm away from the transection point. Within 6 h of transection, secondary axotomy occurred at about 300 microm-rostral and -caudal to the primary transection point, which finally formed strongly-NF/peripherin-IR-positive zipper-like axon segments at the transection site. Notably, sprouting of secondarily severed axons was observed within 6 h of injury. The regenerative axons, which extended toward the transection site, could not traverse the transection site where the zipper-like axon segments resided. The zipper-like axon segments showed abnormal axolemmal permeability through the leakage of an axonal tracer. Western blot analysis revealed a slight increase in peripherin content in transected spinal cord. Local treatment with cycloheximide suppressed the axotomy-induced peripherin-IR-enhancement in severed ends, suggesting the occurrence of intra-axonal peripherin synthesis in vivo. Treatment with calpain inhibitors frequently formed abnormally swollen microtubule-free ends, which suggests that calpain-activation is critical for functional growth cone formation in adult rat spinal cord. These observations indicate that adult rat cordotomy with a scalpel results in the rapid formation of intensely NF-IR-positive zipper-like axon segments at the transection site, which are similar to "preserved fibers" reported by Ramon y Cajal [Ramon y Cajal S (1928) Degeneration and regeneration in the nervous system. New York: Hafner]. On the other hand, axonal regenerative responses start within 6 h of injury, which may be supported by calpain-activation and intra-axonal protein synthesis.


Asunto(s)
Axones/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas de Filamentos Intermediarios/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Neurofilamentos/metabolismo , Traumatismos de la Médula Espinal/patología , Animales , Axones/efectos de los fármacos , Cicloheximida/farmacología , Dextranos/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Modelos Biológicos , Regeneración Nerviosa/fisiología , Periferinas , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Tubulina (Proteína)/metabolismo
11.
Sci Total Environ ; 407(1): 304-14, 2008 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-18848720

RESUMEN

A baseline for persistent organohalogen compound (POC) accumulation in the Antarctic keystone species, Antarctic krill (Euphausia superba) has been established for a 50 degrees longitudinal range of the eastern Antarctic sector. Samples of adult krill, caught from 12 sites distributed between 30 degrees and 80 degrees E (60-70 degrees S), were analysed for >100 organohalogen compounds including chlorinated pesticides, polychlorinated biphenyls (PCBs), polybrominated organic compounds and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs). Organochlorine pesticides dominated measured krill contaminant burdens with hexachlorobenzene (HCB) as the single most abundant compound quantified. Krill HCB concentrations were comparable to those detected at this trophic level in both the Arctic and temperate northwest Atlantic, lending support for the hypothesis that HCB will approach global equilibrium at a faster rate than other POCs. Para, para'-dichlorodiphenylethene (p,p'-DDE) was detected at notable concentrations. Measurements of DDT and its degradation products provide an important baseline for monitoring the temporal and geographical influence of renewed, DDT usage for malaria-control in affected southern hemisphere countries. In contrast to the Arctic, PCBs did not feature prominently in contaminant burdens of Antarctic krill. The major commercial polybrominated diphenyl ether (PBDE) congeners -99 and -47 were quantified at low background levels with clear concentration spikes observed at around 70 degrees E , in the vicinity of modern, active research stations. The likelihood that local anthropogenic activities are supplementing low PBDE levels, delivered otherwise primarily via long range environmental transport, is discussed. The suspected naturally occurring brominated organic compound, 2,4,6-tribromoanisole (TBA), was a ubiquitous contaminant in all samples whereas the only PCDD/Fs quantifiable were trace levels of octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,7,8/1,2,3,4,7,9-hexachlorodibenzofuran (HxCDF). With the aims of; i) Generating a robust and broadly applicable POC auditing platform for the scarcely studied eastern Antarctic sector; ii) Determining the compounds accumulating in Antarctic krill for further toxicity evaluation studies and iii) Establishing a baseline for Antarctic predator exposure to POCs, this study represents one of the most comprehensive reports of POC contamination of the Antarctic food web to date.


Asunto(s)
Monitoreo del Ambiente/métodos , Euphausiacea/efectos de los fármacos , Hidrocarburos Halogenados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Regiones Antárticas , Carga Corporal (Radioterapia) , Recolección de Datos , Euphausiacea/metabolismo , Hidrocarburos Halogenados/farmacocinética , Contaminantes Químicos del Agua/farmacocinética
12.
Kyobu Geka ; 61(3): 242-5, 2008 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-18323193

RESUMEN

A 78-year-old man had previously undergone replacement of ascending aorta using gelatin-resorcin-formalin (GRF) glue for acute aortic dissection. Five years later, a follow-up computed tomography (CT) showed an aortic root pseudoaneurysm. Ultrasound cardiography revealed moderate aortic regurgitation and pseudoaneurysm of aortic root. Aortic root replacement was planned based on a clinical diagnosis of an anastomotic pseudoaneurysm of the aortic root. The patient was discharged without complication 26 days after surgery. In the histopathological examination, the necrotic change of smooth muscle cells in the aortic media was revealed. Previous reports suggests that the use of GRF glue for reconstructing the dissected aorta results in higher rates of postoperative redissection or pseudoaneurysm. Therefore, careful postoperative follow-up is necessary in such cases and further improvements in the quality of glue or alternative methods will be necessary to prevent problems in the first place.


Asunto(s)
Aneurisma Falso/etiología , Aorta/cirugía , Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular , Formaldehído/efectos adversos , Gelatina/efectos adversos , Complicaciones Posoperatorias/etiología , Resorcinoles/efectos adversos , Enfermedad Aguda , Anciano , Combinación de Medicamentos , Estudios de Seguimiento , Humanos , Masculino
13.
Andrology ; 6(6): 903-908, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29968337

RESUMEN

Although reports have shown evidence for penile length (PL) shortening after radical prostatectomy (RP), the association between neoadjuvant androgen deprivation therapy (NADT) and PL after RP has yet to be determined. This study evaluates chronological changes in PL after NADT and RP. Stretched PLs (SPLs) of 143 patients, 41 of whom had undergone NADT, were measured before, 10 days after, and 1, 3, 6, 9, 12, 18, and 24 months after RP. Chronological erectile function and testosterone levels were then evaluated. SPL was shortest 10 days after RP in both the NADT (-) and NADT (+) groups and gradually recovered in length thereafter. SPL in the NADT (-) group was significantly longer than that in the NADT (+) group before RP. However, no significant differences in SPLs were found between both groups 6 months after RP. Although all subjects in the NADT (+) group had testosterone levels of <50 ng/dL before RP, such levels increased after RP. Before RP, the NADT (-) group was found to have significantly better erectile function than the NADT (+) group. However, differences in erectile function between the NADT (-) and NADT (+) groups after RP were not significant. This report is the first to show that among patients with prostate cancer, those who underwent NADT had greater PL recovery after RP than those who did not. Data regarding PL recovery after NADT and RP obtained in this study could be useful for patients with prostate cancer who plan to undergo such procedures.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos/uso terapéutico , Terapia Neoadyuvante , Pene/patología , Prostatectomía/métodos , Neoplasias de la Próstata/terapia , Anciano , Quimioterapia Adyuvante , Humanos , Masculino , Persona de Mediana Edad , Erección Peniana , Pene/fisiopatología , Estudios Prospectivos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/fisiopatología , Testosterona/sangre , Factores de Tiempo , Resultado del Tratamiento
14.
Science ; 362(6410): 65-69, 2018 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-30166438

RESUMEN

In metals, orbital motions of conduction electrons on the Fermi surface are quantized in magnetic fields, which is manifested by quantum oscillations in electrical resistivity. This Landau quantization is generally absent in insulators. Here, we report a notable exception in an insulator-ytterbium dodecaboride (YbB12). The resistivity of YbB12, which is of a much larger magnitude than the resistivity in metals, exhibits distinct quantum oscillations. These unconventional oscillations arise from the insulating bulk, even though the temperature dependence of the oscillation amplitude follows the conventional Fermi liquid theory of metals with a large effective mass. Quantum oscillations in the magnetic torque are also observed, albeit with a lighter effective mass.

15.
Mol Biol Cell ; 5(9): 977-88, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7841525

RESUMEN

Chinese hamster ovary (CHO) cells transfected with the integrin alpha 2 subunit formed a stable VLA-2 heterodimer that mediated cell adhesion to collagen. Within CHO cells spread on collagen, but not fibronectin, wild-type alpha 2 subunit localized into focal adhesion complexes (FACs). In contrast, alpha 2 with a deleted cytoplasmic domain was recruited into FACs whether CHO cells were spread on collagen or fibronectin. Thus, as previously seen for other integrins, the alpha 2 cytoplasmic domain acts as a negative regulator, preventing indiscriminate integrin recruitment into FACs. Notably, ligand-independent localization of the VLA-2 alpha 2 subunit into FACs was partially prevented if only one or two amino acids were present in the alpha 2 cytoplasmic domain (beyond the conserved GFFKR motif) and was completely prevented by four to seven amino acids. The addition of two alanine residues (added to GFFKR) also partially prevented ligand-independent localization. In a striking inverse correlation, the same mutants showing increased ligand-independent recruitment into FACs exhibited diminished alpha 2-dependent adhesion to collagen. Thus, control of VLA-2 localization may be closely related to the suppression of cell adhesion to collagen. In contrast to FAC localization and collagen adhesion results, VLA-2-dependent binding and infection by echovirus were unaffected by either alpha 2 cytoplasmic domain deletion or exchange with other cytoplasmic domains.


Asunto(s)
Adhesión Celular , Integrinas/química , Receptores de Antígeno muy Tardío/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células CHO , Colágeno , Cricetinae , Citoplasma/metabolismo , Enterovirus Humano B/metabolismo , Fibronectinas , Integrinas/genética , Integrinas/fisiología , Ligandos , Microscopía Fluorescente , Datos de Secuencia Molecular , Receptores Virales/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Relación Estructura-Actividad
16.
Kyobu Geka ; 60(4): 329-33, 2007 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-17416102

RESUMEN

Total aortic arch replacement using the 'elephant trunk (ET)' procedure has commonly been applied to acute aortic dissection, but enlargement of a residual false lumen of the descending thoracic aorta sometimes occurs. We performed endovascular stent-grafting to close the entry as the second operation and obtained successful outcomes. From April 1997 to January 2004, we performed the modified ET procedure for acute aortic dissection in 29 patients and evaluated postoperative changes of the false lumen. In many cases of the residual false lumen, kinks and wrinkles were observed at the site of the ET grafts in the descending aorta. An adequate length of ET would be about 8 cm long to prevent kinking, and a diameter about 20 mm to prevent wrinkles.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Enfermedad Aguda , Adulto , Anciano , Combinación de Medicamentos , Femenino , Formaldehído/administración & dosificación , Gelatina/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Tereftalatos Polietilenos , Resorcinoles/administración & dosificación
17.
Am J Hosp Palliat Care ; 34(4): 366-372, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-26843534

RESUMEN

BACKGROUND: Internal medicine residents are frequently called upon to provide palliative care to hospitalized patients, but report feeling unprepared to do so effectively. Curricular development to enhance residents' palliative care skills and competencies requires an understanding of current beliefs, attitudes and learning priorities. METHODS: We conducted a qualitative study consisting of semi-structured interviews with ten internal medicine residents to explore their understanding of and experiences with palliative care. RESULTS: All of the residents interviewed had a sound theoretical understanding of palliative care, but faced many challenges in being able to provide care in practice. The challenges described by residents were system-related, patient-related and provider-related. They identified several priority areas for further learning, and discussed ways in which their current education in palliative care could be enhanced. CONCLUSIONS: Our findings provide important insights to guide curricular development for internal medicine trainees. The top five learning priorities in palliative care that residents identified in our study were: 1) knowing how and when to initiate a palliative approach, 2) improving communication skills, 3) improving symptom management skills, 4) identifying available resources, and 5) understanding the importance of palliative care. Residents felt that their education in palliative care could be improved by having a mandatory rotation in palliative care, more frequent didactic teaching sessions, more case-based teaching from palliative care providers, opportunities to be directly observed, and increased support from palliative care providers after-hours.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Medicina Interna/educación , Internado y Residencia/organización & administración , Cuidados Paliativos/organización & administración , Competencia Clínica , Comunicación , Femenino , Humanos , Entrevistas como Asunto , Masculino , Manejo del Dolor , Cuidados Paliativos/psicología , Investigación Cualitativa , Factores de Tiempo
18.
Rev Sci Instrum ; 88(8): 085111, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28863664

RESUMEN

In this study, we developed a user-friendly automatic powder diffraction measurement system for Debye-Scherrer geometry using a capillary sample at beamline BL02B2 of SPring-8. The measurement system consists of six one-dimensional solid-state (MYTHEN) detectors, a compact auto-sampler, wide-range temperature control systems, and a gas handling system. This system enables to do the automatic measurement of temperature dependence of the diffraction patterns for multiple samples. We introduced two measurement modes in the MYTHEN system and developed new attachments for the sample environment such as a gas handling system. The measurement modes and the attachments can offer in situ and/or time-resolved measurements in an extended temperature range between 25 K and 1473 K and various gas atmospheres and pressures. The results of the commissioning and performance measurements using reference materials (NIST CeO2 674b and Si 640c), V2O3 and Ti2O3, and a nanoporous coordination polymer are presented.

19.
Mar Biotechnol (NY) ; 8(6): 686-96, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16924375

RESUMEN

The diet of Antarctic krill (Euphausia superba) has been studied using a variety of techniques, but current methods still suffer from problems that are difficult to solve. This study examined an alternative approach utilizing DNA as a prey biomarker. Methods were developed for the preservation, extraction, and identification of prey DNA from krill collected in the field. Group-specific polymerase chain reaction (PCR) was used to amplify diatom prey (Phylum: Bacillariophyta) and the results from DNA clone libraries were compared with microscopic diet analysis. DNA analysis was superior to microscopy for prey detection. However, differences in prey relative abundance estimates between the two techniques suggested some bias in the DNA-based estimates. Quantification showed that large amounts of prey DNA had been successfully preserved and extracted. Overall the results suggest that the application of DNA-based diet analysis to krill warrants further investigation, particularly for prey that are difficult to study using other methods.


Asunto(s)
ADN/metabolismo , Dieta , Euphausiacea/genética , Euphausiacea/fisiología , Animales , Biomarcadores/metabolismo , ADN/análisis , Conducta Alimentaria , Filogenia
20.
J Phys Condens Matter ; 28(29): 296001, 2016 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-27250516

RESUMEN

Synchrotron powder diffraction, magnetization, and specific heat measurements have been used to investigate the structural and magnetic phase transitions in the spinel-type vanadate Fe(V1-x Cr x )2O4 (0.0 ⩽ x ⩽ 1.0). We observed five different transitions in our polycrystalline samples. The canted-type ferrimagnetic phase transition accompanied by the lattice distortion was suppressed by Cr substitution (x = 0.2). Additionally, high-resolution synchrotron powder diffraction revealed that the low-temperature orthorhombic phase appears in FeV2O4 below 30 K and disappears by subtle Cr doping. In contrast, for x ⩾ 0.7, we observed a different magnetic transition of possibly conical-type ferrimagnetic ordering that did not induce significant lattice distortion at the transition temperature. We performed structural refinements for low-temperature phases and suggest that the crystal system of Fe(V1-x Cr x )2O4 at 15K is an orthorhombic lattice for all x values. In the orthorhombic phase, a unique behaviour was observed, with the lattice constants a and b approaching each other as Cr doping increased. This behaviour can be explained by the change of orbitally ordered states of the Fe(2+) ions.

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