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1.
J Intensive Care Med ; 34(2): 104-108, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460590

RESUMO

BACKGROUND: Admission to an intensive care unit (ICU) specialized for brain and spine injury patients is associated with improved outcome. We investigated the effects of the first dedicated, combined neurological and neurosurgical ICU (NeuroICU) in Korea on patient outcomes. METHODS: The first dedicated NeuroICU in Korea was established in March 2013. We retrospectively analyzed the clinical data and compared the outcomes between patients admitted to the ICU before and after NeuroICU establishment. The predicted mortality of NeuroICU patients was calculated using their Acute Physiology and Chronic Health Evaluation II scores. Patients' functional outcomes were evaluated using their modified Rankin scale (mRS) scores at 6 months after ICU admission, which were obtained from medical records or telephone interviews. RESULTS: We included 2487 patients, 1572 and 915 of whom were admitted prior to and after NeuroICU establishment, respectively. The demographic characteristics, Glasgow Coma Scale scores, and disease proportions did not differ significantly between the groups. The length of ICU stay and the number of days on ventilation were significantly lower in NeuroICU patients than they were in general ICU patients ( P = .024, P = .001). Intensive care unit mortality was significantly lower in NeuroICU patients (7.3% vs 4.7%, P = .012). The predicted mortality was obtained from 473 NeuroICU patients. The mortality ratio (observed mortality/predicted mortality) was 0.34 (8.9%/26.1%), and 228 (48.1%) patients showed good functional recovery (mRS, 0-2). CONCLUSION: Our findings suggest that admission to a dedicated NeuroICU significantly improves the neurological outcomes of patients with brain and spine injuries, including their postoperative care, in Korea.

2.
Adv Sci (Weinh) ; 11(29): e2309467, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38626368

RESUMO

Spin-transfer torque (STT) and spin-orbit torque (SOT) form the core of spintronics, allowing for the control of magnetization through electric currents. While the sign of SOT can be manipulated through material and structural engineering, it is conventionally understood that STT lacks a degree of freedom in its sign. However, this study presents the first demonstration of manipulating the STT sign by engineering heavy metals adjacent to magnetic materials in magnetic heterostructures. Spin torques are quantified through magnetic domain-wall speed measurements, and subsequently, both STT and SOT are systematically extracted from these measurements. The results unequivocally show that the sign of STT can be either positive or negative, depending on the materials adjacent to the magnetic layers. Specifically, Pd/Co/Pd films exhibit positive STT, while Pt/Co/Pt films manifest negative STT. First-principle calculations further confirm that the sign reversal of STT originates from the sign reversal of spin polarization of conduction electrons.

3.
Sci Rep ; 14(1): 9476, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38658634

RESUMO

Interfacial magnetic interactions between different elements are the origin of various spin-transport phenomena in multi-elemental magnetic systems. We investigate the coupling between the magnetic moments of the rare-earth, transition-metal, and heavy-metal elements across the interface in a GdFeCo/Pt thin film, an archetype system to investigate ferrimagnetic spintronics. The Pt magnetic moments induced by the antiferromagnetically aligned FeCo and Gd moments are measured using element-resolved x-ray measurements. It is revealed that the proximity-induced Pt magnetic moments are always aligned parallel to the FeCo magnetic moments, even below the ferrimagnetic compensation temperature where FeCo has a smaller moment than Gd. This is understood by a theoretical model showing distinct effects of the rare-earth Gd 4f and transition-metal FeCo 3d magnetic moments on the Pt electronic states. In particular, the Gd and FeCo work in-phase to align the Pt moment in the same direction, despite their antiferromagnetic configuration. The unexpected additive roles of the two antiferromagnetically coupled elements exemplify the importance of detailed interactions among the constituent elements in understanding magnetic and spintronic properties of thin film systems.

4.
Nat Commun ; 14(1): 7648, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996445

RESUMO

Magnetic domain-wall devices such as racetrack memory and domain-wall shift registers facilitate massive data storage as hard disk drives with low power portability as flash memory devices. The key issue to be addressed is how perfectly the domain-wall motion can be controlled without deformation, as it can replace the mechanical motion of hard disk drives. However, such domain-wall motion in real media is subject to the stochasticity of thermal agitation with quenched disorders, resulting in severe deformations with pinning and tilting. To sort out the problem, we propose and demonstrate a new concept of domain-wall control with a position error-free scheme. The primary idea involves spatial modulation of the spin-orbit torque along nanotrack devices, where the boundary of modulation possesses broken inversion symmetry. In this work, by showing the unidirectional motion of domain wall with position-error free manner, we provide an important missing piece in magnetic domain-wall device development.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33579011

RESUMO

This study aimed to measure lead (Pb) and cadmium (Cd) exposure levels in residents living near a zinc (Zn) smelter in Seokpo-myeon, Bonghwa-gun, South Korea, and identify factors affecting exposure. Residents aged ≥20 years living within 3 km and ≥30 km away from the smelter were classified as the exposure group (n = 549), and the control group (n = 265), respectively. Data were obtained through a questionnaire survey. Blood Pb levels in the exposure group (4.19 µg/dL) were higher than in the control group (2.70 µg/dL). The exposure group (1.32 µg/L) also had higher urinary Cd concentrations than the control group (0.80 µg/L). Male sex, older age, previous work at the smelter, smoking, and proximity to the smelter were associated with higher blood Pb levels on multivariate analysis; urinary Cd concentration was significantly higher in women, those who were older, those with experience of working in a Zn smelter or mine, those with proximity to the Zn smelter, and those who consumed locally grown vegetables. In conclusion, Zn smelters are major source of Pb and Cd pollution and require ongoing public health management to prevent potential adverse health effects.


Assuntos
Cádmio , Chumbo , Idoso , Cádmio/análise , Poluição Ambiental , Feminino , Humanos , Chumbo/análise , Masculino , República da Coreia , Zinco/análise
6.
J Stroke ; 18(3): 337-343, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27488978

RESUMO

BACKGROUND AND PURPOSE: The use of decompressive hemicraniectomy (DHC) for the treatment of malignant cerebral edema can decrease mortality rates. However, this benefit is not sufficient to justify its use in elderly patients. We investigated the effects of therapeutic hypothermia (TH) on safety, feasibility, and functional outcomes in elderly patients with malignant middle cerebral artery (MCA) infarcts. METHODS: Elderly patients 60 years of age and older with infarcts affecting more than two-thirds of the MCA territory were included. Patients who could not receive DHC were treated with TH. Hypothermia was started within 72 hours of symptom onset and was maintained for a minimum of 72 hours with a target temperature of 33°C. Modified Rankin Scale (mRS) scores at 3 months following treatment and complications of TH were used as functional outcomes. RESULTS: Eleven patients with a median age of 76 years and a median National Institutes of Health Stroke Scale score of 18 were treated with TH. The median time from symptom onset to initiation of TH was 30.3±23.0 hours and TH was maintained for a median of 76.7±57.1 hours. Shivering (100%) and electrolyte imbalance (82%) were frequent complications. Two patients died (18%). The mean mRS score 3 months following treatment was 4.9±0.8. CONCLUSIONS: Our results suggest that extended use of hypothermia is safe and feasible for elderly patients with large hemispheric infarctions. Hypothermia may be considered as a therapeutic alternative to DHC in elderly individuals. Further studies are required to validate our findings.

7.
J Clin Neurol ; 7(3): 164-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22087212

RESUMO

BACKGROUND: Carotid cavernous fistula (CCF) is an abnormal communication between the carotid artery and the cavernous sinus. The pathogenesis of spontaneous CCF remains unclear, although sinus thrombosis is known to be a predisposing factor for dural arteriovenous fistula. Because spontaneous CCFs are mainly of the dural type, we considered that thrombogenic conditions, such as, protein S deficiency might be associated with CCF. CASE REPORT: A 42-year-old woman complained of conjunctival injection and retro-orbital pain that first appeared 1-month before visiting our hospital. She had no history of head trauma or intracranial surgery. Exophthalmos and chemosis were observed in her left eye, which also had lower visual acuity and higher intraocular pressure than the right eye. Magnetic resonance images and cerebral angiography revealed a left dural CCF. Her protein S was low, at 41% (normal range: 70-140%), but other hematologic values related to coagulation were normal. Her symptoms were relieved after initial transvenous coil embolization. However, a newly developed sixth-nerve palsy was detected 4 days after initial embolization. Follow-up angiography revealed a minimal shunt, and thus transvenous coil embolization was repeated. Two days later, the ophthalmoplegia started reducing, and 1-month later it had almost disappeared. CONCLUSIONS: To the best of our knowledge, this is the first report of spontaneous dural CCF in a Korean patient with concurrent protein S deficiency. Interestingly, transient sixth-nerve palsy developed after transvenous coil embolization in this patient. This additional symptom caused by the residual fistula was relieved after additional transarterial embolization.

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