This article is concerned with the testing complete independence for the elements of observed vector. Schott proposed the testing statistic T and gave limiting null distribution under the ...high-dimensional asymptotic framework that the sample size n and the dimensionality p go to infinity together while p/n converges to a positive constant. In this article we give a one-term asymptotic expansion of the null distribution for T as
min
{
n
,
p
}
tends toward infinity. We derive a correction of the critical point for Schott's test based on this expansion. The finite sample size and dimensionality performance for attained significance level is evaluated in a simulation study and the results are compared to those of Schott's test.
Key Clinical Message
Mucinous carcinoma of the skin is clinically characterized by good mobility, slow growth, a macroscopically smooth surface, no easy contact bleeding, and no internal flow on ...color Doppler; it is thus difficult to distinguish from benign tumors.
A 58‐year‐old man presented to our clinic complaining of a right cheek induration, growing over the previous 6 months. The tumor surface was smooth, pink, did not bleed easily, and approximately 10 mm in size with good mobility. Ultrasonography revealed a well‐circumscribed hypoechoic homogenous tumor with posterior acoustic enhancement; color Doppler displayed no internal flow. Preoperative diagnosis was intradermal type nevus or dermatofibroma. An excisional biopsy was performed under local anesthesia. The biopsy specimen unexpectedly showed tumor cells with an epithelial alveolar configuration floating in a mucin lake. The tumor cells contained enlarged nuclei and formed atypical columnar epithelium, arranged in fused, honeycomb‐like glandular ducts, indicating mucinous carcinoma.
The tumor surface was smooth, pink in color, did not bleed easily, and was approximately 10 mm in size with good mobility.
Key Clinical Message
Sudden onset bulging of the upper arm may indicate biceps tendon rupture.
We describe a 72‐year‐old man with Popeye's sign. The patient experienced a sudden shock in his right ...humerus while mowing grass with his right arm using wide sweeps of a scythe. His right upper arm had an obvious bulging appearance after 3 days, indicating a rupture of the biceps tendon.
Myocarditis caused by the mRNA‐1273 coronavirus disease 2019 vaccine must be considered for patients complaining of acute constant general fatigue postvaccination.
Adapting to changes in food availability is a central challenge for survival. Glucose is an important resource for energy production, and therefore many organisms synthesize and retain sugar storage ...molecules. In insects, glucose is stored in two different forms: the disaccharide trehalose and the branched polymer glycogen. Glycogen is synthesized and stored in several tissues, including in muscle and the fat body. Despite the major role of the fat body as a center for energy metabolism, the importance of its glycogen content remains unclear. Here, we show that glycogen metabolism is regulated in a tissue-specific manner under starvation conditions in the fruit fly
The mobilization of fat body glycogen in larvae is independent of Adipokinetic hormone (Akh, the glucagon homolog) but is regulated by sugar availability in a tissue-autonomous manner. Fat body glycogen plays a crucial role in the maintenance of circulating sugars, including trehalose, under fasting conditions. These results demonstrate the importance of fat body glycogen as a metabolic safeguard in
.
Background
New York City emerged as an epicenter of the coronavirus disease 2019 (COVID-19) pandemic.
Objective
To describe the clinical characteristics and risk factors associated with mortality in ...a large patient population in the USA.
Design
Retrospective cohort study.
Participants
6493 patients who had laboratory-confirmed COVID-19 with clinical outcomes between March 13 and April 17, 2020, who were seen in one of the 8 hospitals and/or over 400 ambulatory practices in the New York City metropolitan area
Main Measures
Clinical characteristics and risk factors associated with in-hospital mortality.
Key Results
A total of 858 of 6493 (13.2%) patients in our total cohort died: 52/2785 (1.9%) ambulatory patients and 806/3708 (21.7%) hospitalized patients. Cox proportional hazard regression modeling showed an increased risk of in-hospital mortality associated with age older than 50 years (hazard ratio HR 2.34, CI 1.47–3.71), systolic blood pressure less than 90 mmHg (HR 1.38, CI 1.06–1.80), a respiratory rate greater than 24 per min (HR 1.43, CI 1.13–1.83), peripheral oxygen saturation less than 92% (HR 2.12, CI 1.56–2.88), estimated glomerular filtration rate less than 60 mL/min/1.73m
2
(HR 1.80, CI 1.60–2.02), IL-6 greater than 100 pg/mL (HR 1.50, CI 1.12–2.03), D-dimer greater than 2 mcg/mL (HR 1.19, CI 1.02–1.39), and troponin greater than 0.03 ng/mL (HR 1.40, CI 1.23–1.62). Decreased risk of in-hospital mortality was associated with female sex (HR 0.84, CI 0.77–0.90), African American race (HR 0.78 CI 0.65–0.95), and hydroxychloroquine use (HR 0.53, CI 0.41–0.67).
Conclusions
Among patients with COVID-19, older age, male sex, hypotension, tachypnea, hypoxia, impaired renal function, elevated D-dimer, and elevated troponin were associated with increased in-hospital mortality and hydroxychloroquine use was associated with decreased in-hospital mortality.
Additive manufacturing is a free-form manufacturing technique in which parts are built in a layer-by-layer manner. Laser powder bed fusion is one of the popular techniques used to fabricate metal ...parts. However, it induces residual stress and distortion during fabrication that adversely affects the mechanical properties and dimensional accuracy of the manufactured parts. Therefore, predicting and avoiding the residual stress and distortion are critical issues. In this study, we propose a topology optimization method that accounts for the distortion. First, we propose a computationally inexpensive analytical model for additive manufacturing that uses laser powder bed fusion and formulated an optimization problem. Next, we approximate the topological derivative of the objective function using an adjoint variable method that is then utilized to update the level set function via a time evolutionary reaction-diffusion equation. Finally, the validity and effectiveness of the proposed optimization method was established using two-dimensional design examples.
•A topology optimization method considering distortion induced by AM process.•Additive manufacturing (AM) process modeling based on the inherent strain method.•An inherent strain identification method and an experimental validation method.
This study proposes a level set-based topology optimization method for designing acoustic structures with viscous and thermal boundary layers in perspective. Acoustic waves propagating in a narrow ...channel are damped by viscous and thermal boundary layers. To estimate these viscothermal effects, we first introduce a sequential linearized Navier–Stokes model based on three weakly coupled Helmholtz equations for viscous, thermal, and acoustic pressure fields. Then, the optimization problem is formulated, where a sound-absorbing structure comprising air and an isothermal rigid medium is targeted, and its sound absorption coefficient is set as an objective function. The adjoint variable method and the concept of the topological derivative are used to approximately obtain design sensitivity. A level set-based topology optimization method is used to solve the optimization problem. Two-dimensional numerical examples are provided to support the validity of the proposed method. Moreover, the mechanisms that lead to the high absorption coefficient of the optimized design are discussed.
•We propose a topology optimization method for viscothermal acoustic systems.•A sequential linearized Navier–Stokes model is combined with topology optimization.•We formulate the optimization problem for the designs of a sound-absorbing structure.•Optimized designs show high absorption coefficients over a certain frequency band.•Multiple resonances are induced in the designs, yielding high absorption performance.
•We propose a topology optimization method for acoustic metasurfaces.•A two-scale homogenization method is combined with a topology optimization method.•Optimized metasurfaces efficiently guide ...transmitted waves in the desired direction.•The proposed method reveals that phase shifts along the metasurface are an important factor.
In this paper, we propose a level set-based topology optimization method for the unit-cell design of acoustic metasurfaces by using a two-scale homogenization method. Based on previous works, we first propose a homogenization method for acoustic metasurfaces that can be combined with topology optimization. In this method, a nonlocal transmission condition depending on the unit cell of the metasurface appears in a macroscale problem. Next, we formulate an optimization problem within the framework of a level set-based topology optimization method, wherein an objective functional is expressed as the macroscopic responses obtained through the homogenization, and material distributions in the unit cell are set as design variables. A sensitivity analysis is conducted based on the concept of the topological derivative. To confirm the validity of the proposed method, two-dimensional numerical examples are provided. First, we provide a numerical example that supports the validity of the homogenization method, and we then perform optimization calculations based on the waveguide settings of the acoustic metasurfaces. In addition, we discuss the mechanism of the obtained optimized structures.
A 73‐year‐old man underwent a stage‐Ⅱ sigmoid colon cancer resection. He was carefully monitored, and metastasis or anastomotic recurrence was noted 51 months later. The anal examination revealed a ...firm pink anal tumor, histologically identified as a metastasis of the colon adenocarcinoma.
Anal metastasis secondary to colon cancer rarely occurs. This report guides clinicians to identify this rare type of metastasis.
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