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1.
Front Chem ; 11: 1258389, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37867996

RESUMEN

Silicate perovskite, with the mineral name bridgmanite, is the most abundant mineral in the Earth's lower mantle. We investigated crystal structures and equations of state of two perovskite-type Fe3+-rich phases, FeMg0.5Si0.5O3 and Fe0.5Mg0.5Al0.5Si0.5O3, at high pressures, employing single-crystal X-ray diffraction and synchrotron Mössbauer spectroscopy. We solved their crystal structures at high pressures and found that the FeMg0.5Si0.5O3 phase adopts a novel monoclinic double-perovskite structure with the space group of P21/n at pressures above 12 GPa, whereas the Fe0.5Mg0.5Al0.5Si0.5O3 phase adopts an orthorhombic perovskite structure with the space group of Pnma at pressures above 8 GPa. The pressure induces an iron spin transition for Fe3+ in a (Fe0.7,Mg0.3)O6 octahedral site of the FeMg0.5Si0.5O3 phase at pressures higher than 40 GPa. No iron spin transition was observed for the Fe0.5Mg0.5Al0.5Si0.5O3 phase as all Fe3+ ions are located in bicapped prism sites, which have larger volumes than an octahedral site of (Al0.5,Si0.5)O6.

2.
J Med Case Rep ; 17(1): 454, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37904251

RESUMEN

BACKGROUND: We report two cases of biceps brachii and brachialis paralysis due to musculocutaneous nerve injury in which elbow joint flexion was reconstructed using rotational transfer of the latissimus dorsi muscle with sutures to the radial and ulnar tuberosities, thereby enabling flexion by simultaneous activation of the humeroradial and humeroulnar joints. In cases of associated brachialis paralysis, weaker flexion strength can be expected when the forearm is in a pronated position than when it is in a supinated state. To the best of our knowledge, no previous study has reported the rotational position of the forearm during elbow joint flexion reconstruction. CASE PRESENTATION: Case 1 involved a 30-year-old Asian male who presented with a rupture of the musculocutaneous, median, radial, and ulnar nerves. Reconstruction was performed by rotational transfer of the latissimus dorsi muscle. In this case, the supination and pronation flexion forces were equal. Case 2 involved a 50-year-old Asian man who presented with partial loss of the musculocutaneous nerve, biceps brachii, and pectoralis major due to debridement. Reconstruction was performed by rotational transfer of the latissimus dorsi muscle. In this case, supination and pronation flexion strengths were demonstrated to be equal. Our reconstruction method used the rotational transfer of the latissimus dorsi muscle; the distal muscle flap was divided into radial and ulnar sides to allow elbow joint flexion by simultaneously activating the humeroradial and humeroulnar joints. These sides were then fixed to the anchors at the radial and ulnar tuberosities. Finally, they were wrapped around the myotendinous junction of the biceps brachii or brachialis and secured using sutures. CONCLUSIONS: Although larger studies are required to verify these methods, this case study successfully demonstrates the following: (1) the flexion strength in the supinated position was equal to that in the pronated position; (2) the stability of the humeroradial and humeroulnar joints was unaffected by the forearm's rotational position; and (3) a satisfactory range of motion of the elbow joint was obtained, with no complications.


Asunto(s)
Articulación del Codo , Músculos Superficiales de la Espalda , Masculino , Humanos , Adulto , Persona de Mediana Edad , Codo , Articulación del Codo/cirugía , Parálisis , Rango del Movimiento Articular
3.
J Hand Surg Asian Pac Vol ; 28(1): 34-44, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36803473

RESUMEN

Background: Open reduction and internal fixation with a plate is one of the alternative treatments for fracture-dislocation of the proximal interphalangeal (PIP) joint. However, it does not always lead to satisfactory results. The aim of this cohort study is to describe the surgical procedure and discuss the factors affecting the treatment results. Methods: We retrospectively reviewed 37 cases of consecutive unstable dorsal fracture-dislocation of the PIP joint treated using a mini-plate. The volar fragments were sandwiched with a plate and dorsal cortex, and screws were used as subchondral support. The average rate of articular involvement was 55.5%. Five patients had concomitant injuries. The mean age of the patients was 40.6 years. Mean time between injury and operation was 11.1 days. The average postoperative follow-up duration was 11 months. Active ranges of motion, % total active motion (TAM) were evaluated postoperatively. The patients were divided into two groups according from Strickland score and Gaine score. Fisher's exact test, Mann-Whitney U test and a logistic regression analysis were used to evaluate the factors affecting the results. Results: The average active flexion, flexion contracture at the PIP joint, and % TAM were 86.3°, 10.5° and 80.6%, respectively. Group I included 24 patients who had both excellent and good scores. Group II included 13 patients who had neither excellent nor good scores. When the groups were compared, there was no significant relationship between the type of fracture-dislocation and the extent of articular involvement. There were significant associations between outcomes and patient age, period from injury to surgical intervention and presence of concomitant injuries. Conclusions: We concluded that meticulous surgical technique leads to satisfactory results. However, factors, including the patient's age, time from injury to surgery and the presence of concomitant injuries needing adjacent joint immobilisation, contribute to unsatisfactory outcomes. Level of Evidence: Level IV (Therapeutic).


Asunto(s)
Traumatismos de los Dedos , Fractura-Luxación , Fracturas Óseas , Luxaciones Articulares , Humanos , Adulto , Estudios de Cohortes , Estudios Retrospectivos , Traumatismos de los Dedos/diagnóstico por imagen , Traumatismos de los Dedos/cirugía , Articulaciones de los Dedos/diagnóstico por imagen , Articulaciones de los Dedos/cirugía , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Fractura-Luxación/diagnóstico por imagen , Fractura-Luxación/cirugía
4.
Gan To Kagaku Ryoho ; 50(13): 1854-1856, 2023 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-38303230

RESUMEN

In recent years, bridge to surgery(BTS), in which surgery is performed after colorectal stenting for obstructive colorectal cancer, has gradually become popular, and laparoscopic surgery is also a treatment option. From January 2020 to December 2022, we retrospectively evaluated clinicopathological factors in 18 colorectal cancer cases who underwent radical resection after colorectal stenting. We found no difference in patient background, histopathological factors, primary anastomosis rate, stoma creation rate, operative time, postoperative complication rate and length of hospital stay between the laparoscopic surgery(L)and open surgery(O)groups. Blood loss was significantly lower in group L. In T4 patients, laparoscopic surgery after colorectal stenting can be safely performed, but conversion to open surgery may be necessary. Surgery after colorectal stenting should be performed based on preoperative accurate imaging and sufficient experience.


Asunto(s)
Neoplasias Colorrectales , Obstrucción Intestinal , Laparoscopía , Humanos , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/complicaciones , Estudios Retrospectivos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Resultado del Tratamiento , Stents/efectos adversos , Laparoscopía/efectos adversos
5.
Proc Natl Acad Sci U S A ; 119(44): e2211243119, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36279458

RESUMEN

Water transported by subducted oceanic plates changes mineral and rock properties at high pressures and temperatures, affecting the dynamics and evolution of the Earth's interior. Although geochemical observations imply that water should be stored in the lower mantle, the limited amounts of water incorporation in pyrolitic lower-mantle minerals suggest that water in the lower mantle may be stored in the basaltic fragments of subducted slabs. Here, we performed multianvil experiments to investigate the stability and water solubility of aluminous stishovite and CaCl2-structured silica, referred to as poststishovite, in the SiO2-Al2O3-H2O systems at 24 to 28 GPa and 1,000 to 2,000 °C, representing the pressure-temperature conditions of cold subducting slabs to hot upwelling plumes in the top lower mantle. The results indicate that both alumina and water contents in these silica minerals increase with increasing temperature under hydrous conditions due to the strong Al3+-H+ charge coupling substitution, resulting in the storage of water up to 1.1 wt %. The increase of water solubility in these hydrous aluminous silica phases at high temperatures is opposite of that of other nominally anhydrous minerals and of the stability of the hydrous minerals. This feature prevents the releasing of water from the subducting slabs and enhances the transport water into the deep lower mantle, allowing significant amounts of water storage in the high-temperature lower mantle and circulating water between the upper mantle and the lower mantle through subduction and plume upwelling. The shallower depths of midmantle seismic scatterers than expected from the pure SiO2 stishovite-poststishovite transition pressure support this scenario.

6.
Nat Commun ; 13(1): 3042, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35650203

RESUMEN

The experimental study of hydrogen-bonds and their symmetrization under extreme conditions is predominantly driven by diffraction methods, despite challenges of localising or probing the hydrogen subsystems directly. Until recently, H-bond symmetrization has been addressed in terms of either nuclear quantum effects, spin crossovers or direct structural transitions; often leading to contradictory interpretations when combined. Here, we present high-resolution in-situ 1H-NMR experiments in diamond anvil cells investigating a range of systems containing linear O-H ⋯ O units at pressure ranges of up to 90 GPa covering their respective H-bond symmetrization. We found pronounced minima in the pressure dependence of the NMR resonance line-widths associated with a maximum in hydrogen mobility, precursor to a localisation of hydrogen atoms. These minima, independent of the chemical environment of the O-H ⋯ O unit, can be found in a narrow range of oxygen oxygen distances between 2.44 and 2.45 Å, leading to an average critical oxygen-oxygen distance of [Formula: see text] Å.

7.
J Synchrotron Radiat ; 29(Pt 2): 409-423, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35254304

RESUMEN

Penetrating, high-energy synchrotron X-rays are in strong demand, particularly for high-pressure research in physics, chemistry and geosciences, and for materials engineering research under less extreme conditions. A new high-energy wiggler beamline P61 has been constructed to meet this need at PETRA III in Hamburg, Germany. The first part of the paper offers an overview of the beamline front-end components and beam characteristics. The second part describes the performance of the instrumentation and the latest developments at the P61B endstation. Particular attention is given to the unprecedented high-energy photon flux delivered by the ten wigglers of the PETRA III storage ring and the challenges faced in harnessing this amount of flux and heat load in the beam. Furthermore, the distinctiveness of the world's first six-ram Hall-type large-volume press, Aster-15, at a synchrotron facility is described for research with synchrotron X-rays. Additionally, detection schemes, experimental strategies and preliminary data acquired using energy-dispersive X-ray diffraction and radiography techniques are presented.

8.
Nature ; 601(7891): 69-73, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34987213

RESUMEN

The 660-kilometre seismic discontinuity is the boundary between the Earth's lower mantle and transition zone and is commonly interpreted as being due to the dissociation of ringwoodite to bridgmanite plus ferropericlase (post-spinel transition)1-3. A distinct feature of the 660-kilometre discontinuity is its depression to 750 kilometres beneath subduction zones4-10. However, in situ X-ray diffraction studies using multi-anvil techniques have demonstrated negative but gentle Clapeyron slopes (that is,  the ratio between pressure and temperature changes) of the post-spinel transition that do not allow a significant depression11-13. On the other hand, conventional high-pressure experiments face difficulties in accurate phase identification due to inevitable pressure changes during heating and the persistent presence of metastable phases1,3. Here we determine the post-spinel and akimotoite-bridgmanite transition boundaries by multi-anvil experiments using in situ X-ray diffraction, with the boundaries strictly based on the definition of phase equilibrium. The post-spinel boundary has almost no temperature dependence, whereas the akimotoite-bridgmanite transition has a very steep negative boundary slope at temperatures lower than ambient mantle geotherms. The large depressions of the 660-kilometre discontinuity in cold subduction zones are thus interpreted as the akimotoite-bridgmanite transition. The steep negative boundary of the akimotoite-bridgmanite transition will cause slab stagnation (a stalling of the slab's descent) due to significant upward buoyancy14,15.

10.
Eur J Trauma Emerg Surg ; 48(3): 2493-2501, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34807271

RESUMEN

PURPOSE: Gustilo-Anderson type IIIB and IIIC open fractures of the lower extremities require reconstruction of extensively injured soft tissues using a free flap; however, impaired blood flow through the flap is an early postoperative complication. To detect flap congestion due to venous thrombosis, blood glucose and lactate level measurements within the flap are taken to determine variations in these levels. We aimed to detect early-stage venous congestion and to perform salvage operations. METHODS: We included 22 limbs with lower leg and foot open fractures, with fracture sites covered using a free flap. A pinprick test was used to measure blood glucose and lactate levels. RESULTS: Of 7 and 15 congested and non-congested limbs, respectively, the 7 congested limbs had a mean flap blood glucose level immediately before salvage surgery of 3.8 ± 2.0 (7.4-1.8) mmol/L. The ratio to blood glucose levels in healthy fingertips was 0.6 ± 0.2 (0.8-0.3). Lactate levels increased to 13.3 ± 5.1 (9.4-22.8) mmol/L. The ratio of blood glucose levels in congested flaps and in healthy fingertips was significantly lower than that in non-congested flaps and in healthy fingertips (p = 0.0016). Lactate levels were significantly higher in patients with congestion (p = 0.0013). Salvage surgery was performed, thrombi were removed, and six limb flaps were viable. CONCLUSION: Flap blood glucose and lactate levels provide a quantitative method of evaluating blood flow and detecting flow abnormalities postoperatively, and are useful in detecting early congestion due to venous thrombosis.


Asunto(s)
Fracturas Abiertas , Colgajos Tisulares Libres , Hiperemia , Traumatismos de la Pierna , Procedimientos de Cirugía Plástica , Glucemia , Fracturas Abiertas/cirugía , Colgajos Tisulares Libres/irrigación sanguínea , Colgajos Tisulares Libres/cirugía , Humanos , Hiperemia/diagnóstico , Hiperemia/etiología , Hiperemia/cirugía , Lactatos , Traumatismos de la Pierna/cirugía , Extremidad Inferior/lesiones , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos , Resultado del Tratamiento
11.
Rev Sci Instrum ; 92(11): 113902, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34852545

RESUMEN

We report a new rapid-quench technique for the Kawai-type multi-anvil press: several important improvements were made to our previous design. As a result, we are able to routinely quench melts with low glass-forming ability and form glasses. Owing to the use of 3D-printed parts to supply the coolant, the new design is easier to assemble and demonstrates better temperature stability and cooling rate. It was also found that the cooling rate is both pressure- and temperature-dependent. The cooling rate increases with increasing pressure from 6700 °C/s at 1 GPa to 8200 °C/s at 5.5 GPa and decreases with increasing temperature at a rate of 550 °C s-1/100 °C. Taking these dependencies into account, the new rapid-quench design produces more than 15% higher cooling rate compared to the previous design. Moreover, enhancing coolant circulation, which was achieved by using tapered inner anvils with holes, additionally increases the cooling rate by about 4%. As the structure of the rapid-quench assembly differs dramatically from other existing designs, pressure calibration and temperature distribution in the experimental cell and sample capsule were determined for the first time. It was found that the first 0.6 MN of press load is not used to generate pressure due to the hard tungsten components in the assembly. At the current state-of-the-art, it is possible to routinely reach a pressure of 9 GPa and a temperature of 2200 K with the temperature variation not exceeding 70 K within the sample capsule.

12.
Nature ; 599(7886): 605-610, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34819683

RESUMEN

Solids in nature can be generally classified into crystalline and non-crystalline states1-7, depending on whether long-range lattice periodicity is present in the material. The differentiation of the two states, however, could face fundamental challenges if the degree of long-range order in crystals is significantly reduced. Here we report a paracrystalline state of diamond that is distinct from either crystalline or amorphous diamond8-10. The paracrystalline diamond reported in this work, consisting of sub-nanometre-sized paracrystallites that possess a well-defined crystalline medium-range order up to a few atomic shells4,5,11-13, was synthesized in high-pressure high-temperature conditions (for example, 30 GPa and 1,600 K) employing face-centred cubic C60 as a precursor. The structural characteristics of the paracrystalline diamond were identified through a combination of X-ray diffraction, high-resolution transmission microscopy and advanced molecular dynamics simulation. The formation of paracrystalline diamond is a result of densely distributed nucleation sites developed in compressed C60 as well as pronounced second-nearest-neighbour short-range order in amorphous diamond due to strong sp3 bonding. The discovery of paracrystalline diamond adds an unusual diamond form to the enriched carbon family14-16, which exhibits distinguishing physical properties and can be furthered exploited to develop new materials. Furthermore, this work reveals the missing link in the length scale between amorphous and crystalline states across the structural landscape, having profound implications for recognizing complex structures arising from amorphous materials.

13.
Rev Sci Instrum ; 92(10): 103902, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34717412

RESUMEN

We attempted to generate ultrahigh pressure and temperature simultaneously using a multi-anvil apparatus by combining the technologies of ultrahigh-pressure generation using sintered diamond (SD) anvils, which can reach 120 GPa, and ultrahigh-temperature generation using a boron-doped diamond (BDD) heater, which can reach 4000 K. Along with this strategy, we successfully generated a temperature of 3300 K and a pressure of above 50 GPa simultaneously. Although the high hardness of BDD significantly prevents high-pressure generation at low temperatures, its high-temperature softening allows for effective pressure generation at temperatures above 1200 K. High temperature also enhances high-pressure generation because of the thermal pressure. We expect to generate even higher pressure in the future by combining SD anvils and a BDD heater with advanced multi-anvil technology.

14.
RSC Adv ; 11(6): 3777-3782, 2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35424266

RESUMEN

Self-ordered anodic porous alumina with a long-range ordered hole arrangement having an inter-hole spacing of over 1.5 µm was prepared by anodization in a citric acid electrolyte containing a small amount of phosphoric acid. The inter-hole spacing of the ordered anodic porous alumina could be controlled within a range of 700 nm to 1.8 µm by adjusting the anodization conditions. The use of an electrolyte with a mixture of water and ethylene glycols, especially tetraethylene glycol, was effective for preparing ordered anodic porous alumina with large inter-hole spacings. The obtained anodic porous alumina is suitable for various applications that require highly ordered hole array structures with large inter-hole spacings.

17.
J Dermatol ; 47(8): 807-833, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32614097

RESUMEN

The Japanese Dermatological Association prepared the clinical guidelines for the "Wound, pressure ulcer and burn guidelines", second edition, focusing on treatments. Among them, "Guidelines for wounds in general" is intended to provide the knowledge necessary to heal wounds, without focusing on particular disorders. It informs the basic principles of wound treatment, before explanations are provided in individual chapters of the guidelines. We updated all sections by collecting references published since the publication of the first edition. In particular, we included new wound dressings and topical medications. Additionally, we added "Question 6: How should wound-related pain be considered, and what should be done to control it?" as a new section addressing wound pain, which was not included in the first edition.


Asunto(s)
Úlcera por Presión , Vendajes , Humanos , Úlcera por Presión/terapia , Cicatrización de Heridas
18.
J Dermatol ; 47(11): 1207-1235, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32343002

RESUMEN

"Wound, pressure ulcer and burn guidelines - 6: Guidelines for the management of burns, second edition" is revised from the first edition which was published in the Japanese Journal of Dermatology in 2016. The guidelines were drafted by the Wound, Pressure Ulcer and Burn Guidelines Drafting Committee delegated by the Japanese Dermatological Association, and intend to facilitate physicians' clinical decisions in preventing, diagnosing and treating burn injury. All sections are updated by collecting documents published since the publication of the first edition. Especially, the recommendation levels of dressing materials newly covered by the Japanese national health insurance are mentioned. In addition, the clinical questions (CQ) regarding the initial treatment of electrical (CQ15) and chemical burns (CQ16), and also the use of escharotomy (CQ22), are newly created.


Asunto(s)
Úlcera por Presión , Vendajes , Humanos , Úlcera por Presión/diagnóstico , Úlcera por Presión/terapia
19.
J Dermatol ; 47(10): 1071-1109, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31960490

RESUMEN

The Japanese Dermatological Association prepared guidelines focused on the treatment of skin ulcers associated with connective tissue disease/vasculitis practical in clinical settings of dermatological care. Skin ulcers associated with connective tissue diseases or vasculitis occur on the background of a wide variety of diseases including, typically, systemic sclerosis but also systemic lupus erythematosus (SLE), dermatomyositis, rheumatoid arthritis (RA), various vasculitides and antiphospholipid antibody syndrome (APS). Therefore, in preparing the present guidelines, we considered diagnostic/therapeutic approaches appropriate for each of these disorders to be necessary and developed algorithms and clinical questions for systemic sclerosis, SLE, dermatomyositis, RA, vasculitis and APS.


Asunto(s)
Enfermedades del Tejido Conjuntivo , Lupus Eritematoso Sistémico , Úlcera por Presión , Enfermedades Cutáneas Vasculares , Úlcera Cutánea , Vasculitis , Humanos , Úlcera Cutánea/diagnóstico , Úlcera Cutánea/tratamiento farmacológico , Úlcera Cutánea/etiología , Vasculitis/diagnóstico , Vasculitis/tratamiento farmacológico
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