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1.
Rev Sci Instrum ; 93(8): 083902, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050107

RESUMO

The development of new modes at x-ray free electron lasers has inspired novel methods for studying fluctuations at different energies and timescales. For closely spaced x-ray pulses that can be varied on ultrafast time scales, we have constructed a pair of advanced instruments to conduct studies targeting quantum materials. We first describe a prototype instrument built to test the proof-of-principle of resonant magnetic scattering using ultrafast pulse pairs. This is followed by a description of a new endstation, the so-called fluctuation-dissipation measurement instrument, which was used to carry out studies with a fast area detector. In addition, we describe various types of diagnostics for single-shot contrast measurements, which can be used to normalize data on a pulse-by-pulse basis and calibrate pulse amplitude ratios, both of which are important for the study of fluctuations in materials. Furthermore, we present some new results using the instrument that demonstrates access to higher momentum resolution.

3.
Nature ; 590(7847): 561-565, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33627814

RESUMO

The fundamental building blocks of the proton-quarks and gluons-have been known for decades. However, we still have an incomplete theoretical and experimental understanding of how these particles and their dynamics give rise to the quantum bound state of the proton and its physical properties, such as its spin1. The two up quarks and the single down quark that comprise the proton in the simplest picture account only for a few per cent of the proton mass, the bulk of which is in the form of quark kinetic and potential energy and gluon energy from the strong force2. An essential feature of this force, as described by quantum chromodynamics, is its ability to create matter-antimatter quark pairs inside the proton that exist only for a very short time. Their fleeting existence makes the antimatter quarks within protons difficult to study, but their existence is discernible in reactions in which a matter-antimatter quark pair annihilates. In this picture of quark-antiquark creation by the strong force, the probability distributions as a function of momentum for the presence of up and down antimatter quarks should be nearly identical, given that their masses are very similar and small compared to the mass of the proton3. Here we provide evidence from muon pair production measurements that these distributions are considerably different, with more abundant down antimatter quarks than up antimatter quarks over a wide range of momenta. These results are expected to revive interest in several proposed mechanisms for the origin of this antimatter asymmetry in the proton that had been disfavoured by previous results4, and point to future measurements that can distinguish between these mechanisms.

4.
Phytopathology ; 110(1): 206-214, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31509476

RESUMO

Soybean mosaic virus and Clover yellow vein virus are two definite species of the genus Potyvirus within the family Potyviridae. Soybean mosaic virus-N (SMV-N) is well adapted to cultivated soybean (Glycine max) genotypes and wild soybean (G. soja), whereas it remains undetectable in inoculated broad bean (Vicia faba). In contrast, clover yellow vein virus No. 30 (ClYVV-No. 30) is capable of systemic infection in broad bean and wild soybean; however, it infects cultivated soybean genotypes only locally. In this study, SMV-N was shown to also infect broad bean locally; hence, broad bean is a host for SMV-N. Based on these observations, it was hypothesized that lack of systemic infection by SMV-N in broad bean and by ClYVV-No. 30 in cultivated soybean is attributable to the incompatibility of multifunctional helper-component proteinase (HC-Pro) in these hosts. The logic of selecting the HC-Pro cistron as a target is based on its established function in systemic movement and being a relevant factor in host range specificity of potyviruses. To test this hypothesis, chimeras were constructed with precise exchanges of HC-Pro cistrons between SMV-N and ClYVV-No. 30. Upon inoculation, both chimeras were viable in infection, but host range specificity of the recombinant viruses did not differ from those of the parental viruses. These observations suggest that (i) HC-Pro cistrons from SMV-N and ClYVV-No. 30 are functionally compatible in infection despite 55.6 and 48.9% nucleotide and amino acid sequence identity, respectively, and (ii) HC-Pro cistrons from SMV-N and ClYVV-No. 30 are not the determinants of host specificity on cultivated soybean or broad beans, respectively.


Assuntos
Glycine max , Especificidade de Hospedeiro , Potyvirus , Especificidade de Hospedeiro/genética , Viabilidade Microbiana/genética , Potyvirus/enzimologia , Potyvirus/genética , Glycine max/genética , Glycine max/virologia
5.
Surg Endosc ; 33(6): 1769-1776, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30291444

RESUMO

BACKGROUND: The number of colorectal cancer cases is increasing, and so the number of laparoscopic colectomy procedures being performed is also increasing, leading to an increased workload for surgeons. However, operating for prolonged time periods may cause surgeons to lose their concentration and develop fatigue. We hypothesized that there is a time-of-day variation in outcome for patients with colorectal cancer who undergo laparoscopic colectomy. The present study aimed to compare the operative outcome between laparoscopic colectomy for colorectal cancer performed in the morning versus the afternoon. METHODS: This was a single-center, retrospective study. All 1961 consecutive patients who underwent laparoscopic surgery for colorectal cancer between 2007 and 2017 were included; 1006 of these patients underwent morning surgery, while 955 underwent afternoon surgery. These patients were analyzed using propensity score matching, giving 791 patients in each group. The short- and long-term outcomes in both groups were compared. RESULTS: Before propensity score matching, the morning group had a larger mean tumor size than the afternoon group (30 cm vs 35 cm; P = 0.0035). After matching, the two groups did not significantly differ in any patient characteristics. Compared with the afternoon group, the morning group had a significantly lesser incidence of intra-operative organ injury (0.25% vs 1.13%; P = 0.027), and a significantly greater incidence of post-operative abdominal abscess (2.03% vs 0.75% P = 0.028). The incidences of other complications and morbidities were similar in both groups. The median operative time in the morning group (201 min) was significantly longer than that in the afternoon group (193 min; P = 0.0124). The two groups did not differ in 5-year overall survival rates and 5-year disease-free rates within any disease stage. CONCLUSIONS: Surgical start times are correlated with surgical outcomes. Our data will help to ensure the safest possible surgeries.


Assuntos
Neoplasias Colorretais/cirurgia , Duração da Cirurgia , Idoso , Idoso de 80 Anos ou mais , Colectomia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Incidência , Japão/epidemiologia , Laparoscopia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Pontuação de Propensão , Estudos Retrospectivos , Análise de Sobrevida
7.
Plant Sci ; 262: 165-168, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28716411

RESUMO

Accelerated soil-nitrifier activity and rapid nitrification are the cause of declining nitrogen-use efficiency (NUE) and enhanced nitrous oxide (N2O) emissions from farming. Biological nitrification inhibition (BNI) is the ability of certain plant roots to suppress soil-nitrifier activity, through production and release of nitrification inhibitors. The power of phytochemicals with BNI-function needs to be harnessed to control soil-nitrifier activity and improve nitrogen-cycling in agricultural systems. Transformative biological technologies designed for genetic mitigation are needed, so that BNI-enabled crop-livestock and cropping systems can rein in soil-nitrifier activity, to help reduce greenhouse gas (GHG) emissions and globally make farming nitrogen efficient and less harmful to environment. This will reinforce the adaptation or mitigation impact of other climate-smart agriculture technologies.


Assuntos
Agricultura/métodos , Gases de Efeito Estufa , Produtos Agrícolas/metabolismo , Produtos Agrícolas/fisiologia , Nitrificação , Óxido Nitroso/metabolismo , Sorghum/genética , Sorghum/metabolismo , Triticum/genética , Triticum/metabolismo
8.
Transplant Proc ; 48(4): 1083-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27320563

RESUMO

BACKGROUND: In this study, we demonstrated our new device for open donor liver surgery with left-sided heptectomy by use of the real-time moving windows (RTMW) method with 8-cm transverse skin incision for living donors from the viewpoints of cosmetic, economic, and safety procedures. METHODS: After the upper abdominal 8-cm transverse skin incision was made, the subcutaneous area was exfoliated and the reverse T-shaped-abdominal incision was made, as in open surgery. After that, the 2 Kent hooks for the upper region and the 2 surgical arms for the lower region were placed. The operative fields of hepatic vein, hepatic hilus, and common hepatic artery were explored, respectively, by use of the RTMW method with the use of the 4 surgical hooks. Hepatic parenchymal dissection was carried out with the use of CUSA and laparosonic coagulating shears. Manipulations of 3 hepatic vessels and the hepatic duct were done by the usual procedure of open surgery. RESULTS: This operative procedure could be performed without laparoscopic techniques. The operative time was 7 hours, without blood transfusion. The operative course was uneventful, and the patient was discharged on postoperative day 11. CONCLUSIONS: Our RTMW method for donor left-sided hepatectomy is considered to be a useful operative procedure from the viewpoints of donor safety, cosmetic advantage, and cost performance.


Assuntos
Dissecação/instrumentação , Hepatectomia/métodos , Transplante de Fígado , Doadores Vivos , Coleta de Tecidos e Órgãos/métodos , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/cirurgia , Feminino , Humanos , Duração da Cirurgia , Sítio Doador de Transplante
9.
Dis Esophagus ; 29(3): 278-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25604848

RESUMO

Gastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances. Although the mechanisms of this association have not been fully elucidated, nighttime reflux plays a central role. However, the detailed characteristics of nighttime reflux occurring during sleep are unknown. The aim of the present study was to examine the characteristics and prevalence of nighttime reflux in the natural sleep environment of GERD patients. Seventeen patients experiencing daily moderate-to-severe heartburn and/or regurgitation were studied using multichannel intraluminal impedance pH monitoring and electroencephalography off-proton pump inhibitor treatment. Nighttime reflux was divided based on reflux type (liquid or gas), acidity (acidic, weakly acidic, or alkaline) and extent (distal only or proximal migration) according to the standard criteria. Nighttime phases were divided as follows: recumbent-awake before falling asleep, nonrapid eye movement, rapid eye movement, awakening from sleep, and post-awakening in the morning. Among 184 nighttime refluxes, 43 (23%) occurred during recumbent-awake before falling asleep, 28 (15%) during nonrapid eye movement, 14 (8%) during rapid eye movement, 86 (46%) during awakening from sleep, and 13 (7%) during post-awakening in the morning. Liquid reflux was more common in awakening during sleep (92%), nonrapid eye movement (100%), and rapid eye movement (100%) compared with awakening before falling asleep (68%). The prevalence of proximal migration was significantly lower in nonrapid eye movement and rapid eye movement than in the other phases. There were no differences in acidity and bolus clearance time among the phases. Thirteen (65%) of 20 events with GERD symptoms had nighttime reflux, suggesting that only 7.1% (13 of 184) of nighttime refluxes were symptomatic. Nighttime reflux was observed in 48 (11%) of 425 awakening episodes during sleep. Different reflux patterns at each phase during nighttime might explain the pathogenesis of GERD and its related sleep disturbances.


Assuntos
Eletroencefalografia/métodos , Monitoramento do pH Esofágico/métodos , Refluxo Gastroesofágico/fisiopatologia , Transtornos do Sono-Vigília/diagnóstico , Sono/fisiologia , Adulto , Idoso , Ritmo Circadiano , Impedância Elétrica , Feminino , Refluxo Gastroesofágico/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Sono-Vigília/etiologia
11.
Animal ; 7 Suppl 2: 322-32, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23739474

RESUMO

Agriculture and livestock production systems are two major emitters of greenhouse gases. Methane with a GWP (global warming potential) of 21, and nitrous oxide (N2O) with a GWP of 300, are largely emitted from animal production agriculture, where livestock production is based on pasture and feed grains. The principal biological processes involved in N2O emissions are nitrification and denitrification. Biological nitrification inhibition (BNI) is the natural ability of certain plant species to release nitrification inhibitors from their roots that suppress nitrifier activity, thus reducing soil nitrification and N2O emission. Recent methodological developments (e.g. bioluminescence assay to detect BNIs in plant root systems) have led to significant advances in our ability to quantify and characterize the BNI function. Synthesis and release of BNIs from plants is a highly regulated process triggered by the presence of NH4 + in the rhizosphere, which results in the inhibitor being released precisely where the majority of the soil-nitrifier population resides. Among the tropical pasture grasses, the BNI function is strongest (i.e. BNI capacity) in Brachiaria sp. Some feed-grain crops such as sorghum also have significant BNI capacity present in their root systems. The chemical identity of some of these BNIs has now been established, and their mode of inhibitory action on Nitrosomonas has been characterized. The ability of the BNI function in Brachiaria pastures to suppress N2O emissions and soil nitrification potential has been demonstrated; however, its potential role in controlling N2O emissions in agro-pastoral systems is under investigation. Here we present the current status of our understanding on how the BNI functions in Brachiaria pastures and feed-grain crops such as sorghum can be exploited both genetically and, from a production system's perspective, to develop low-nitrifying and low N2O-emitting production systems that would be economically profitable and ecologically sustainable.


Assuntos
Agricultura/métodos , Brachiaria/genética , Produtos Agrícolas/genética , Nitrificação , Óxido Nitroso/metabolismo , Criação de Animais Domésticos , Animais , Brachiaria/metabolismo , Produtos Agrícolas/metabolismo , Desnitrificação , Ecossistema , Gado/fisiologia , Solo/química , Microbiologia do Solo , Sorghum/genética , Sorghum/metabolismo
12.
Ann Bot ; 112(2): 297-316, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23118123

RESUMO

BACKGROUND: Agriculture is the single largest geo-engineering initiative that humans have initiated on planet Earth, largely through the introduction of unprecedented amounts of reactive nitrogen (N) into ecosystems. A major portion of this reactive N applied as fertilizer leaks into the environment in massive amounts, with cascading negative effects on ecosystem health and function. Natural ecosystems utilize many of the multiple pathways in the N cycle to regulate N flow. In contrast, the massive amounts of N currently applied to agricultural systems cycle primarily through the nitrification pathway, a single inefficient route that channels much of this reactive N into the environment. This is largely due to the rapid nitrifying soil environment of present-day agricultural systems. SCOPE: In this Viewpoint paper, the importance of regulating nitrification as a strategy to minimize N leakage and to improve N-use efficiency (NUE) in agricultural systems is highlighted. The ability to suppress soil nitrification by the release of nitrification inhibitors from plant roots is termed 'biological nitrification inhibition' (BNI), an active plant-mediated natural function that can limit the amount of N cycling via the nitrification pathway. The development of a bioassay using luminescent Nitrosomonas to quantify nitrification inhibitory activity from roots has facilitated the characterization of BNI function. Release of BNIs from roots is a tightly regulated physiological process, with extensive genetic variability found in selected crops and pasture grasses. Here, the current status of understanding of the BNI function is reviewed using Brachiaria forage grasses, wheat and sorghum to illustrate how BNI function can be utilized for achieving low-nitrifying agricultural systems. A fundamental shift towards ammonium (NH4(+))-dominated agricultural systems could be achieved by using crops and pastures with high BNI capacities. When viewed from an agricultural and environmental perspective, the BNI function in plants could potentially have a large influence on biogeochemical cycling and closure of the N loop in crop-livestock systems.


Assuntos
Lactonas/farmacologia , Nitrificação/efeitos dos fármacos , Nitrogênio/metabolismo , Nitrosomonas/metabolismo , Raízes de Plantas/metabolismo , Agricultura , Brachiaria/química , Brachiaria/metabolismo , Produtos Agrícolas , Ecossistema , Fertilizantes , Lactonas/química , Raízes de Plantas/química , Compostos de Amônio Quaternário/metabolismo , Solo , Sorghum/química , Sorghum/metabolismo , Triticum/química , Triticum/metabolismo
13.
Eur J Gynaecol Oncol ; 33(4): 353-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091889

RESUMO

OBJECTIVE: Radical hysterectomy (RH) is a standard treatment for locally advanced non-squamous cell carcinoma (N-SCC) of the uterine cervix, but there have been no reports on whether neoadjuvant chemotherapy (NAC) followed by radical hysterectomy could improve the outcome of patients with this disease. MATERIALS AND METHODS: This multicenter retrospective study enrolled 77 patients with Stage IB2 to IIB N-SCC of the uterine cervix. Of these, 27 patients were treated with NAC prior to radical hysterectomy (NAC group) and 50 with RH alone (RH group). The two-year recurrence-free survival (RFS) rate, progression-free survival (PFS), and overall survival (OS) were compared between the two groups. Clinical parameters such as clinical stage, histological type, and postoperative treatment were also examined between the groups. RESULTS: While the two-year RFS rates were 81.5% and 70.0% in NAC and RH groups, respectively (p = 0.27) and the median PFS was 51 months and 35 months in NAC and RH groups, respectively (p = 0.35), the median OS was 58 months and 48 months in NAC and RH groups, respectively, which was significant (p = 0.0014). The median OS of patients with mucinous adenocarcinoma in NAC group was significantly higher than that in RH group: 58 months versus 37 months (p = 0.03). CONCLUSION: NAC prior to RH may offer the prognostic advantage of patients with locally advanced N-SCC of the uterine cervix, especially mucinous adenocarcinoma.


Assuntos
Histerectomia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Neoplasias do Colo do Útero/mortalidade
14.
Phys Rev Lett ; 107(19): 197401, 2011 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-22181642

RESUMO

Water-ethanol mixtures exhibit interesting anomalies in their macroscopic properties. Despite a lot of research, the origin of the anomalies and the microscopic structure itself is still far from completely known. We have utilized the synchrotron x-ray Compton scattering technique to elucidate the structure of aqueous ethanol from a new experimental perspective. The technique is uniquely sensitive to the local molecular geometries at the angstrom and subangstrom scales. The experiments reveal two distinct mixing regimes in terms of geometry: the dilute 5 mol % and the concentrated >15 mol % regimes. By comparing with pure liquids, the former regime is characterized by an intramolecular and the latter by an intermolecular change. The findings bring new light to evaluating the hypothesis of formation of clathratelike structures at the dilute concentrations.


Assuntos
Etanol/química , Soluções/química , Água/química , Difração de Raios X , Modelos Químicos , Estrutura Molecular , Espalhamento de Radiação
15.
Neuroscience ; 193: 249-58, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21782903

RESUMO

Viral vector-mediated gene transfer has become increasingly valuable for primate brain research, in particular for application of genetic methods (e.g. optogenetics) to study neuronal circuit functions. Neuronal cell tropisms and infection patterns are viable options for obtaining viral vector-mediated transgene delivery that is selective for particular neuronal pathways. For example, several types of viral vectors can infect axon terminals (retrograde infections), which enables targeted transgene delivery to neurons that directly project to a particular viral injection region. Although recent studies in rodents have demonstrated that adeno-associated virus serotype 8 (AAV8) and 9 (AAV9) efficiently transduce neurons, the tropisms and infection patterns remain poorly understood in primate brains. Here, we constructed recombinant AAV8 or AAV9, which expressed an enhanced green fluorescent protein (EGFP) gene driven by a ubiquitous promoter (AAV8-EGFP and AAV9-EGFP, respectively), and stereotaxically injected it into several brain regions in marmosets and macaque monkeys. Immunohistochemical analyses revealed almost exclusive colocalization of EGFP fluorescence via AAV9-mediated gene transfer with a neuron-specific marker, indicating endogenous neuronal tropism of AAV9, which was consistent with our previous results utilizing AAV8. Injections of either AAV8-EGFP or AAV9-EGFP into the marmoset striatum resulted in EGFP expression in local striatal neurons as a result of local infection, as well as expression in dopaminergic neurons of the substantia nigra via retrograde transport along nigrostriatal axonal projections. Retrograde infections were also observed in the frontal cortex and thalamus, which are known to have direct projections to the striatum. These local and retrograde gene transfers were further demonstrated in the geniculocortical pathway of the marmoset visual system. These findings indicate promising capabilities of AAV8 and AAV9 to deliver molecular tools into a range of primate neural systems in pathway-specific manners through their neuronal tropisms and infection patterns.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Dependovirus/fisiologia , Vias Neurais/fisiologia , Neurônios/metabolismo , Animais , Encéfalo/metabolismo , Callithrix , Dependovirus/classificação , Dependovirus/genética , Técnicas de Transferência de Genes , Vetores Genéticos/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo
16.
Interv Neuroradiol ; 17(1): 49-57, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21561558

RESUMO

Although endovascular surgery is now widely used to treat intracranial aneurysms, no comparative studies of clipping versus endovascular surgery to address distal ACA aneurysms at the same institution are available. We compared the results of these treatment modalities to address distal ACA aneurysms at our institution. We treated 68 patients with ruptured distal ACA aneurysms (endovascular surgery, n=13; clipping surgery, n=55). We performed a retrospective comparison of the treatment outcomes. To study the efficacy of endovascular surgery we classified all our cases into three types: type A were small-necked aneurysms, type B were wide-necked aneurysms on the parent artery, and type C were aneurysms in which the A3 portion of the ACA arose from the aneurysmal dome near the neck. Intraoperative hemorrhage occurred in 7.7% of aneurysms treated by endovascular surgery and in 34.5% treated by clipping surgery. In 7.7% of the endovascularly-treated aneurysms we noted coil migration during embolization surgery; venous infarction due to cortical vein injury occurred in 7.3% of clipped aneurysms. Of the endovascularly-treated aneurysms, 7.7% manifested post-embolization hemorrhage; 23.1% manifested coil compaction. In clipping surgery, postoperative rerupture occurred in 1.8% of the aneurysms; one patient presented with postoperative acute epidural hematoma. Clip dislocation was noted in 1.8% of aneurysms. Angiography was indicative of post-treatment vasospasm in 7.7% of aneurysms treated endovascularly and in 50.9% of the clipped aneurysms. The clinical outcome showed no significant difference between endovascular surgery and clipping surgery.


Assuntos
Aneurisma Roto/cirurgia , Aneurisma Roto/terapia , Embolização Terapêutica , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneurisma Roto/diagnóstico por imagem , Angiografia Cerebral , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Instrumentos Cirúrgicos , Resultado do Tratamento
17.
Nat Mater ; 9(11): 889-93, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20953183

RESUMO

The quantum Hall effect arises from the cyclotron motion of charge carriers in two-dimensional systems. However, the ground states related to the integer and fractional quantum Hall effect, respectively, are of entirely different origin. The former can be explained within a single-particle picture; the latter arises from electron correlation effects governed by Coulomb interaction. The prerequisite for the observation of these effects is extremely smooth interfaces of the thin film layers to which the charge carriers are confined. So far, experimental observations of such quantum transport phenomena have been limited to a few material systems based on silicon, III-V compounds and graphene. In ionic materials, the correlation between electrons is expected to be more pronounced than in the conventional heterostructures, owing to a large effective mass of charge carriers. Here we report the observation of the fractional quantum Hall effect in MgZnO/ZnO heterostructures grown by molecular-beam epitaxy, in which the electron mobility exceeds 180,000 cm(2) V(-1) s(-1). Fractional states such as ν = 4/3, 5/3 and 8/3 clearly emerge, and the appearance of the ν = 2/5 state is indicated. The present study represents a technological advance in oxide electronics that provides opportunities to explore strongly correlated phenomena in quantum transport of dilute carriers.

18.
Interv Neuroradiol ; 16(3): 317-21, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20977867

RESUMO

Non-traumatic subgaleal hematoma is very rare. We present a case of refractory non-traumatic subgaleal hematoma occurring in a 15-year-old male patient. The patient was successfully treated by embolization of the superficial temporal artery. This therapeutic approach to refractory non-traumatic subgaleal hematoma is discussed.


Assuntos
Embolização Terapêutica , Hematoma Epidural Craniano/diagnóstico por imagem , Hematoma Epidural Craniano/terapia , Artérias Temporais/diagnóstico por imagem , Adolescente , Angiografia Cerebral , Humanos , Masculino , Tomografia Computadorizada por Raios X , Curetagem a Vácuo
19.
Kyobu Geka ; 63(5): 371-4, 2010 May.
Artigo em Japonês | MEDLINE | ID: mdl-20446604

RESUMO

We successfully performed 1-port video-assisted thoracic surgery (VATS) for primary spontaneous pneumothorax using Mini Loop Retractor II in 137 (39%) of 351 patients from March 2005 to May 2009 at Tokyo Teishin Hospital. This retractor is accessible to the thoracic cavity by simple skin puncture. It can hold and retract the lung freely like forceps. We made a 2 cm incision and inserted a 5 mm thoracoscope. We held the affected lung by the retractor and performed wedge resection by endoscopic staplers through skin incision. The operation time was 34.8 +/- 10.9 minutes and the blood loss was trace level in all cases. The duration of chest drainage was 1.2 +/- 0.8 days and the postoperative hospital stay was 2.8 +/- 1.2 days. There was no major complications. The recurrence of pneumothorax was noted in 17 (12.4%) cases. One-port VATS for pneumothorax using Mini Loop Retractor II can be applied easily and safely to selected patients.


Assuntos
Pneumotórax/cirurgia , Instrumentos Cirúrgicos , Cirurgia Torácica Vídeoassistida , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Neuroscience ; 166(1): 333-40, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20006681

RESUMO

Rodents exhibit aversive behavior toward a diet that lacks at least one of the essential amino acids. We sought to determine whether the particular form of anorexia caused by such diets could be ameliorated by the administration of orexigenic peptides while simultaneously analyzing the neural mechanisms underlying anorexia. Rats were fed a valine-deficient diet, which induced severe anorexia (reducing food consumption by 80%). The severe anorexia was associated with a significant decrease in the cerebrospinal fluid valine concentration and hyper-ghrelinemia. Between 6 and 12 days after initiation of the valine-deficient diet, we injected rats twice daily with valine and/or an orexigenic peptide (ghrelin, neuropeptide Y, or agouti-related protein) either i.p. or i.c.v.. We then measured dietary intake. An i.c.v. valine injection allowed earlier food intake compared with an i.p valine injection and increased the density of c-Fos-positive ependymal cells lining the third ventricle. Whereas an i.c.v. injection of ghrelin or neuropeptide Y increased consumption of the valine-deficient diet, i.p injection of ghrelin or i.c.v. injection of agouti-related protein did not. Following i.c.v. administration of either valine or ghrelin, we did not observe complete recovery of consumption of the valine-deficient diet. This may be due to the ineffectiveness of peripheral ghrelin and central agouti-related protein and/or to conditioned aversion to the valine-deficient diet. Since ghrelin is known to be involved in food anticipatory activities, whether the hyper-ghrelinemia observed in valine-deficient rats play role in foraging behavior other than food intake is the future study to be investigated.


Assuntos
Anorexia/metabolismo , Regulação do Apetite/fisiologia , Apetite/fisiologia , Grelina/metabolismo , Valina/deficiência , Proteína Relacionada com Agouti/metabolismo , Proteína Relacionada com Agouti/farmacologia , Animais , Anorexia/tratamento farmacológico , Anorexia/fisiopatologia , Apetite/efeitos dos fármacos , Regulação do Apetite/efeitos dos fármacos , Proteínas Alimentares/metabolismo , Modelos Animais de Doenças , Epêndima/citologia , Epêndima/metabolismo , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Comportamento Alimentar/fisiologia , Alimentos Formulados , Grelina/farmacologia , Hipotálamo/citologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Neuropeptídeo Y/metabolismo , Neuropeptídeo Y/farmacologia , Ratos , Ratos Wistar , Terceiro Ventrículo/citologia , Terceiro Ventrículo/metabolismo , Valina/líquido cefalorraquidiano , Valina/farmacologia
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