712 research outputs found
Indeterminacy and Market Instability
This note shows that indeterminacy arising from an economy exhibiting production with social constant returns to scale may be related to the instability of the consumption goods market equilibrium. Furthermore, trade does not contribute to indeterminacy; indeterminacy arises becasue each country’s equilibrium path is already indeterminate before trade.Indeterminacy, Market Instability
Autarkic Indeterminacy and Trade Determinacy
We extend the model of Nishimura and Shimomura (2002) to consider a two-country framework where under autarky indeterminacy arises in one country but determinacy in the other, and show that indeterminacy could be eliminated when trade takes place between the two.Indeterminacy, Trade, Two-Country Framework.
Angiotensin-converting enzyme (ACE) inhibition in type 2, diabetic patients – interaction with ACE insertion/deletion polymorphism
Angiotensin-converting enzyme (ACE) insertion(I)/deletion (D) polymorphism may modify the effect of inhibition of the renin–angiotensin–aldosterone system (RAAS) on survival and cardiorenal outcomes in type 2, diabetes. A consecutive cohort of 2089 Chinese type 2 diabetic patients with mean (±standard deviation) age of 59.7±13.1 years were genotyped for this polymorphism by polymerase chain reaction method and were followed prospectively for a median period of 44.6 (interquartile range: 23.7, 57.5) months. Clinical outcomes, including all-cause mortality, cardiovascular and renal end points, were examined. The frequency for I allele was 67.1 and 32.9% for D allele, with observed genotype frequencies of 45.8, 42.6, and 11.6% for 3, DI and DD, respectively. ACE DD polymorphism was an independent predictor for renal end point with hazard ratio (HR) (95% confidence interval) of 1.72 (1.16, 2.56), but not for cardiovascular end point or mortality. After controlling for confounding factors, including ACE I/D genotype, the usage of RAAS inhibitors was associated with reduced risk of mortality (HR 0.34 (0.23, 0.50)) and renal end point (HR 0.55 (0.40, 0.75)). On subgroup analysis, the beneficial effects on survival (II vs DI vs DD: HR 0.29 (0.16, 0.51) vs 0.25 (0.14, 0.46) vs 1.33 (0.41, 4.31)) and renoprotection (II vs DI vs DD: 0.52 (0.30, 0.90) vs 0.43 (0.25, 0.72) vs 0.95 (0.43, 2.12)) were most evident in II and DI carriers. In conclusion, inhibition of RAAS was associated with reduced risk of mortality and occurrence of renal end point in Chinese type 2 diabetic patients. These benefits were most evident among II and DI carriers
First principle study of intrinsic defects in hexagonal tungsten carbide
The characteristics of intrinsic defects are important for the understanding
of self-diffusion processes, mechanical strength, brittleness, and plasticity
of tungsten carbide, which present in the divertor of fusion reactors. Here, we
use first-principles calculations to investigate the stability of point defects
and their complexes in WC. Our calculation results confirm that the formation
energies of carbon defects are much lower than that of tungsten defects. The
outward relaxations around vacancy are found. Both interstitial carbon and
interstitial tungsten atom prefer to occupy the carbon basal plane projection
of octahedral interstitial site. The results of isolated carbon defect
diffusion show that the carbon vacancy stay for a wide range of temperature
because of extremely high diffusion barriers, while carbon interstitial
migration is activated at lower temperatures for its considerable lower
activation energy. These results provide evidence for the presumption that the
800K stage is attributed by the annealing out of carbon vacancies by long-range
migration.Comment: Submitted to Journal of Nuclear Material
Sinonasal complications of severe acute respiratory syndrome coronavirus-2: A single center case series
Background: The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has resulted in an unprecedented global pandemic. Most infected patients are either asymptomatic or have mild upper respiratory infection symptoms. However, life-threatening sequelae have been observed. In this report, we reviewed nine cases of patients with severe complications from sinonasal disease in the setting of acute SARS-CoV-2 infection. Methods: IRB approval was obtained prior to study initiation. A retrospective chart review was performed of patients admitted to a tertiary hospital with complex sinonasal symptoms that required otolaryngologic evaluation and management in the setting of concomitant SARS-CoV-2 infection. Results: Nine patients, ranging from ages 3 to 71 years, with sinonasal disease and simultaneous SARS-CoV-2 infection were identified. Initial presentations ranged from asymptomatic infection to mild/moderate disease (nasal obstruction, cough) or more severe sequelae including epistaxis, proptosis, or neurologic changes. SARS-CoV-2 tests were positive from one to 12 days after symptom onset, with three patients receiving SARS-CoV-2-directed treatment. Complex disease presentations included bilateral orbital abscesses, suppurative intracranial infection, cavernous sinus thrombosis with epidural abscess, systemic hematogenous spread with abscess development in four distinct anatomic locations, and hemorrhagic benign adenoidal tissue. Eight of nine patients (88.8%) required operative intervention. Patients with abscesses also required prolonged, culture-directed antibiotic courses. Conclusion: Though most SARS-CoV-2 infections are asymptomatic and/or self-limited, there is significant morbidity and mortality in patients with severe disease sequela as outlined in our reported cases. This suggests early identification and treatment of sinonasal disease in this patient population is critical to minimizing poor outcomes. Further research on the pathophysiology of these atypical presentations is needed. Level of Evidence: 4 (Case Series)
Higgs sector and R-parity breaking couplings in models with broken U(1)_B-L gauge symmetry
Four different supersymmetric models based on SU(2)_L X U(1)_R X U(1)_B-L and
SU(2)_L X SU(2)_R X U(1)_B-L gauge symmetry groups are studied. U(1)_B-L
symmetry is broken spontaneously by a vacuum expectation value (VEV) of a
sneutrino field. The right-handed gauge bosons may obtain their mass solely by
sneutrino VEV. The physical charged lepton and neutrino are mixtures of
gauginos, higgsinos and lepton interaction eigenstates. Explicit formulae for
masses and mixings in the physical lepton fields are found. The spontaneous
symmetry breaking mechanism fixes the trilinear R-parity breaking couplings.
Only some special R-parity breaking trilinear couplings are allowed. There is a
potentially large trilinear lepton number breaking coupling - which is unique
to left-right models - that is proportional to the SU(2)_R gauge coupling g_R.
The couplings are parametrized by few mixing angles, making the spontaneous
R-parity breaking a natural ``unification framework'' for R-parity breaking
couplings in SUSYLR models.Comment: 19 pages, no figures, uses REVTeX. To be published in PR
Ganoderma lucidum extract inhibits proliferation of SW 480 human colorectal cancer cells
Aim: Ganoderma lucidum is a commonly used Chinese herb and an important ingredient in traditional Chinese medicine herbal formulations for immune dysfunction related illnesses. The effects of this medicinal mushroom on human colorectal cancer cells have not yet been evaluated. In this study, we investigated the effects of Ganoderma lucidum extract using SW 480 human colorectal cancer cell line. Materials and Methods: Two different fractions of Ganoderma lucidum extract, i.e., a fraction containing mainly polysaccharides (GLE-1), and a triterpenoid fraction without polysaccharides (GLE-2) were analyzed. Their antiproliferative activity was evaluated by cell proliferation assay and 3H-thymidine incorporation assay. Scavenging effects of DPPH radical were assessed using ESR-spectroscopy. Results: Our data showed that both GLE-1 and GLE-2 significantly inhibited the proliferation of SW 480 cells. The inhibitory effect of GLE-2 was much stronger than that of GLE-1. GLE-1 inhibited DNA synthesis in the cells and reduced the formation of DPPH radicals. Conclusion: Ganoderma lucidum extract inhibits proliferation of human colorectal cancer cells and possesses antioxidant properties.Цель: для лечения заболеваний, связанных с нарушениями функционирования иммунной системы, в традиционной китайской
медицине часто используют препараты на основе Ganoderma lucidum. В данной работе было изучено влияние экстракта Ganoderma
lucidum на клетки колоректального рака человека линии SW 480. Материалы и методы: изучали две фракции экстракта
Ganoderma lucidum: фракцию GLE-1, содержащую полисахариды, и тритерпеноидную фракцию GLE-2. Их рост-ингибирующую
активность определяли с помощью анализа клеточной пролиферации и по включению 3
H-тимидина. Для оценки антиоксидантной
активности использовали ЕСР-спектроскопию. Результаты: обе фракции Ganoderma lucidum подавляли пролиферацию клеток
SW 480. Рост-ингибирующий эффект GLE-2 был более выраженным, чем фракции GLE-1. Фракция GLE-1 подавляла синтез ДНК
в клетках линии SW 480 и понижала уровень формирования DPPH радикалов. Выводы: экстракт Ganoderma lucidum подавляет
пролиферацию клеток колоректального рака человека и обладает антиоксидантными свойствами
A novel tumor-based epithelial-to-mesenchymal transition score that associates with prognosis and metastasis in patients with stage II/III colorectal cancer
It is increasingly appreciated that host factors within the tumor center and microenvironment play a key role in dictating colorectal cancer (CRC) outcomes. As a result, the metastatic process has now been defined as a result of epithelial–mesenchymal transition (EMT). Establishment of the role of EMT within the tumor center and its effect on the tumor microenvironment would be beneficial for prognosis and therapeutic intervention in CRC. The present study assessed five immunohistochemical EMT markers within the tumor center on a 185 Stage II/III CRC patient tissue microarray. In 185 patients with CRC, cytoplasmic snail (HR 1.94 95% confidence interval [CI] 1.15–3.29, p = 0.012) and a novel combined EMT score (HR 3.86 95% CI 2.17–6.86, p < 0.001) were associated with decreased cancer‐specific survival. The combined EMT score was also associated with increased tumor budding (p = 0.046), and systemic inflammation (p = 0.007), as well as decreased memory T‐cells within the stroma (p = 0.030) and at the invasive margin (p = 0.035). Furthermore, the combined EMT score was associated with cancer‐specific survival independent of TNM‐stage (HR 4.12 95% CI 2.30–7.39, p < 0.001). In conclusion, a novel combined EMT score stratifies patient's survival in Stage II/III CRC and associates with key factors of tumor metastasis. Therefore, the combined EMT score could be used to identify patients at risk of micrometastases and who may benefit from standard adjuvant therapy, potentially in combination with EMT blockade
Lepton flavor violation decays in the topcolor-assisted technicolor model and the littlest Higgs model with parity
The new particles predicted by the topcolor-assisted technicolor ()
model and the littlest Higgs model with T-parity (called model) can
induce the lepton flavor violation () couplings at tree level or one loop
level, which might generate large contributions to some processes. Taking
into account the constraints of the experimental data on the relevant free
parameters, we calculate the branching ratios of the decay processes
with = , and
in the context of these two kinds of new physics models. We find
that the model and the model can indeed produce significant
contributions to some of these decay processes.Comment: 24 pages, 7 figure
The Periodic Instability of Diameter of ZnO Nanowires via a Self-oscillatory Mechanism
ZnO nanowires with a periodic instability of diameter were successfully prepared by a thermal physical vapor deposition method. The morphology of ZnO nanowires was investigated by SEM. SEM shows ZnO possess periodic bead-like structure. The instability only appears when the diameter of ZnO nanowires is small. The kinetics and mechanism of Instability was discussed at length. The appearance of the instability is due to negative feed-back mechanism under certain experimental conditions (crystallization temperature, vapor supersaturation, etc)
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