To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Major depressive disorder (MDD) is highly heterogeneous and can be classified as treatment-resistant depression (TRD) or antidepressant-responsive depression (non-TRD) based on patients' responses to antidepressant treatment. Methods for distinguishing between TRD and non-TRD are critical clinical concerns. Deficits of cortical inhibition (CI) have been reported to play an influential role in the pathophysiology of MDD. Whether TRD patients' CI is more impaired than that of non-TRD patients remains unclear.
Paired-pulse transcranial magnetic stimulation (ppTMS) was used to measure cortical inhibitory function including GABAA- and GABAB-receptor-related CI and cortical excitatory function including glutamate-receptor-related intracortical facilitation (ICF). We recruited 36 healthy controls (HC) and 36 patients with MDD (non-TRD, n = 16; TRD, n = 20). All participants received evaluations for depression severity and ppTMS examinations. Non-TRD patients received an additional ppTMS examination after 3 months of treatment with the SSRI escitalopram.
Patients with TRD exhibited reduced short-interval intracortical inhibition (SICI) and long-interval intracortical inhibition (LICI), as shown by abnormally higher estimates, than those with non-TRD or HC (F = 11.030, p < 0.001; F = 10.309, p < 0.001, respectively). After an adequate trial of escitalopram treatment, the LICI of non-TRD reduced significantly (t = − 3.628, p < 0.001), whereas the ICF remained lower than that of HC and showed no difference from pretreatment non-TRD.
TRD was characterized by relatively reduced CI, including both GABAA- and GABAB-receptor-mediated neurons while non-TRD preserved partial CI. In non-TRD, SSRIs may mainly modulate GABAB-receptor-related LICI. Our findings revealed distinguishable features of CI in antidepressant-resistant and responsive major depression.
This paper extends the Chamley–Judd framework by introducing preference externalities in a neoclassical growth model, and finds that the optimal capital tax increases with the extent of social-status seeking or negative leisure externalities. Furthermore, this paper finds that differences in leisure externalities lead to a distinct impact on optimal factor income taxes, and hence may serve as a plausible vehicle to explain the empirical differences in factor income taxation in the United States and Europe.
The Doba gabbro was collected from an exploration well through the Cretaceous Doba basin of southern Chad. The gabbro is composed mostly of plagioclase, clinopyroxene and Fe–Ti oxide minerals and displays cumulus mineral textures. Whole-rock 40Ar–39Ar step-heating geochronology yielded a Late Permian plateau age of 257 ± 1 Ma. The major and trace elemental geochemistry shows that the gabbro is tholeiitic in composition and has trace element ratios (i.e. La/YbN > 7; Sm/YbPM > 3.4; Nb/Y > 1; Zr/Y > 5) indicative of a basaltic melt derived from a garnet-bearing mantle source. The moderately enriched Sr–Nd isotopes (i.e. ISr = 0.70495 to 0.70839; ɛNd(T) = −1.0 to −1.3) fall within the mantle array (i.e. OIB-like) and are similar to other Late Permian plutonic rocks of North-Central Africa (i.e. ISr = 0.7040 to 0.7070). The enriched isotopic composition of the Doba gabbro contrasts with the more depleted compositions of the spatially associated Neoproterozoic post-Pan-African within-plate granites. The contrasting Nd isotope composition between the older within-plate granites and the younger Doba gabbro indicates that different mantle sources produced the rocks and thus may mark the southern boundary of the Saharan Metacraton.
The phase evolution, nucleation, and sintered ceramics of barium titanate (BaTiO3, BT) powder prepared by solid-state synthesis with an ultrafine starting material (27 m2/g of BaCO3 and 190 m2/g of TiO2) were investigated in this study. Surface diffusion between BaCO3 and TiO2 was observed at a relatively low temperature of 400 °C by transmission electron microscopy. Rapid nucleation of the BT and cubic BT phases was observed at 500 °C by x-ray diffraction. The derivative thermogravimetry curve clearly shows a single step of BT formation at 600 °C. In short, pure BT particles with an average particle size of 250 nm and high tetragonality were prepared by solid-state synthesis, which produced X7R ceramics with high dielectric permittivity, high insulation resistance, and a clear core–shell structure.
We investigated a cluster of postoperative febrile episodes and episodes of Acinetobacter baumannii bacteremia in obstetrics and gynecology wards after an electrical blackout and loss of the water supply. The use of patient-controlled analgesia was the only independent risk factor associated with postoperative fever, and A. baumannii isolates recovered from the blood of patients who had received patient-controlled analgesia were genetically related to an isolate recovered from the diluted morphine solution used for this procedure. After inappropriate preparation of the morphine solution was identified and stopped, the outbreak ended.
We report two cases of carcinoma in situ in the external auditory canal (EAC), presenting with symptoms such as pain, long-term itching of the ear, easy contact bleeding, canal otorrhea and hearing loss. Otoscopic examination revealed granulation tissue and a greyish-black tumour with irregular surface. The first patient had previously been diagnosed with otitis externa with persistent ear itching for the past three years. The second patient had received tympanoplasty for treatment of chronic otitis media on the right ear ten years ago. The first case was treated with wide excision, whereas the second patient received resection of the skin of the EAC together with its adjacent soft tissue, followed by skin grafting. No tumour recurrence was noted in the fourth and third post-operative year for the first and second patient respectively. We suggest that EAC carcinoma can be detected early and treated.
Strenuous exercise is known to induce oxidative stress leading to the generation of free radicals. The purpose of the present study was to investigate the effects of lycopene, an antioxidant nutrient, at a relatively low dose (2·6 mg/kg per d) and a relatively high dose (7·8 mg/kg per d) on the antioxidant status of blood and skeletal muscle tissues in rats after exhaustive exercise. Rats were divided into six groups: sedentary control (C); sedentary control with low-dose lycopene (CLL); sedentary control with high-dose lycopene (CHL); exhaustive exercise (E); exhaustive exercise with low-dose lycopene (ELL); exhaustive exercise with high-dose lycopene (EHL). After 30 d, the rats in the three C groups were killed without exercise, but the rats in the three E groups were killed immediately after an exhaustive running test on a motorised treadmill. The results showed that xanthine oxidase (XO) activities of plasma and muscle, and muscular myeloperoxidase (MPO) activity in group E were significantly increased compared with group C. Compared with group E, the elevations of XO and MPO activities of muscle were significantly decreased in group EHL. The malondialdehyde concentrations of plasma and tissues in group E were significantly increased by 72 and 114 %, respectively, compared with those in group C. However, this phenomenon was prevented in rats of the ELL and EHL groups. There was no significant difference in the GSH concentrations of erythrocytes in each group; however, exhaustive exercise resulted in a significant decrease in the GSH content of muscle. In conclusion, these results suggested that lycopene protected muscle tissue from oxidative stress after exhaustive exercise.
To determine risk factors for hemodialysis catheter-related bloodstream infections (HCRBSIs) and investigate whether use of maximal sterile barrier precautions would prevent HCRBSIs.
Tertiary-care medical center hemodialysis unit.
Open trial with historical comparison and case-control study of risk factors for HCRBSIs.
Prospective surveillance was used to compare HCRBSI rates for 1 year before and after implementation of maximal sterile barrier precautions. A case–control study compared 50 case-patients with HCRBSI with 51 randomly selected control-patients.
The HCRBSI rate was 1.6% per 100 dialysis runs (CI95, 1.1%–2.3%) in the first year and 0.77% (CI95, 0.5%–1.1%) in the second year (P = .0106). The most frequent cause of HCRBSI was MRSA in the first year (15 of 32) and MSSA in the second year (13 of 18). Ten MRSA blood isolates in the first year were identical by PFGE. Diabetes mellitus was a risk factor for HCRBSI. Age, gender, site of hemodialysis central venous catheter (CVC), other underlying diseases, coma score, APACHE II score, serum albumin level, and cholesterol level were not associated with HCRBSI and did not change between the 2 years. Hospital stay was prolonged for case-patients (32.78 ± 20.96 days) versus control-patients (22.75 ± 17.33 days), but mortality did not differ.
Use of maximal sterile barrier precautions during the insertion of CVCs reduced HCRBSIs in dialysis patients and seemed cost-effective. Diabetes mellitus was associated with HCRBSI. An outbreak of MRSA in the first year was likely caused by cross-infection via medical personnel.
Effects of TiO2 addition on the conduction mechanism of buried resistors in low temperature cofired ceramics were investigated. Remarkable increases in electrical resistivity and attractive decreases in the temperature coefficient of resistance were observed by the addition of TiO2 for all ratios of RuO2/glass investigated. Such significant effects can be attributed to a larger separation observed between RuO2 particles. The results were compared with the calculated data from theoretical model of tunneling barrier, showing that good agreement could be obtained. In addition, while the distance separation was taken into account as a fixed constant, it was found that the resistivity of buried resistor decreased with increasing TiO2 contents in the glass at higher weight ratios of TiO2/glass. This result implies that a substitution takes place due to the Si+4 displacement by Ti+4 in the glass, resulting in a looser network structure and a lower resistivity value.
In this work, high quality silicon dioxide (SiO2) films were prepared by large-area plasmaenhanced chemical vapor deposition (LA-PECVD) using tetraethylorthosilicate(TEOS)-oxygen based chemistry. The effects of various short-time plasma treatments on these as-deposited TEOS oxide were also investigated. Different plasma treatments such as O2, N2O, and NH3 were used in our experiments. Electrical characteristics were exploited to examine the effects of plasma treatments. It was shown that after N2O, and NH3 plasma treatments, the electrical strength of oxide was enhanced. Besides, NH3 plasma treatment exhibited the highest enhancement efficiency. O2- plasma treatment, however, showed some harmful effects on the electrical properties of the TEOS oxide. The reliability tests including charge to breakdown (Qbd) and bias temperature stress (BTS) were also analyzed in these samples. Although better pre-stress characteristics were observed in those samples treated by NH3-plasma, samples with N2O plasma treatment showed superior stress endurance. Consequently, N2O plasma treatment seems to be the best candidate for future TFTs under the consideration of long-term reliability.
Optimal control models of aggregate milk supply and demand behavior are used to describe the optimal phasing of the deregulatory dairy price support in the presence of supply growth. Producers are assumed to face costs of adjustment, and are myopic with respect to price expectations and the adoption of the new quasi-fixed factor augmenting technology.