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In the adult bone marrow (BM), endothelial cells (ECs) are an integral component of the hematopoietic stem cell (HSC)-supportive niche, which modulates HSC activity by producing secreted and membrane-bound paracrine signals. Within the BM, distinct vascular arteriole, transitional, and sinusoidal EC subtypes display unique paracrine expression profiles and create anatomically-discrete microenvironments. However, the relative contributions of vascular endothelial subtypes in supporting hematopoiesis is unclear. Moreover, constitutive expression and off-target activity of currently available endothelial-specific and endothelial-subtype-specific murine cre lines potentially confound data analysis and interpretation. To address this, we describe two tamoxifen-inducible cre-expressing lines, Vegfr3-creERT2 and Cx40-creERT2, that efficiently label sinusoidal/transitional and arteriole endothelium respectively in adult marrow, without off-target activity in hematopoietic or perivascular cells. Utilizing an established mouse model in which cre-dependent recombination constitutively-activates MAPK signaling within adult endothelium, we identify arteriole ECs as the driver of MAPK-mediated hematopoietic dysfunction. These results define complementary tamoxifen-inducible creERT2-expressing mouse lines that label functionally-discrete and non-overlapping sinusoidal/transitional and arteriole EC populations in the adult BM, providing a robust toolset to investigate the differential contributions of vascular subtypes in maintaining hematopoietic homeostasis. [ABSTRACT FROM AUTHOR]

Purpose: The pathophysiology of penis extends to erectile dysfunction (ED) to conditions including sexually transmitted diseases (STDs) and cancer. To date, there has been little research evaluating vascular drainage from the penis. We aimed to evaluate penile blood flow in vivo and analyze its possible relationship with the lymphatic maker. Materials and Methods: We established an in vivo system designed to assess the dynamic blood outflow from the corpus cavernosum (CC) by dye injection. To analyze lymphatic characteristics in the CC, the expression of Lyve‐1, the key lymphatic endothelium marker, was examined by the in vitro system and lipopolysaccharide (LPS) injection to mimic the inflammatory conditions. Results: A novel cavernography methods enable high‐resolution morphological and functional blood drainage analysis. The expression of Lyve‐1 was detected along the sinusoids. Furthermore, its prominent expression was also observed after penile LPS injection and in the erectile condition. Conclusions: The current in vivo system will potentially contribute to the assessment of penile pathology from a novel viewpoint. In addition, current analyses revealed inducible Lyve‐1 expression for LPS injection and the erection state, which requires further analyses on penile lymphatic system. [ABSTRACT FROM AUTHOR]

The maximum output voltage of the audio amplifier is limited to the magnitude of the power supply voltage of the power transistor or the operational amplifier on the final amplifier. This limits the maximum power of the audio amplifier output. The way to enlarge the output power of the audio amplifier without increasing the voltage is the bridge method or bridged modes. With this method a bridge amplifier will be generated. This Bridge Amplifier is also known as Bridge-Tied Load (BTL) or Bridged Transformerless. The principle of Bridge Amplifiers is to use a pair of final amplifiers whose outputs have opposite phase each other. There are 3 ways to make a pair of power amplifiers have opposing phases: with internal modification, with an audio transformer (phase splitting audio input transformer) and with a simple active phase reversal splitter circuit). This paper will discuss Bridge Amplifiers with simple phase inverting circuits. A pair of audio power amplifiers using two TDA2050 chips which are operated at ± 19 Volt supply voltage. The phase inverting circuit using IC TL072. Sinusoidal signal with an amplitude of 200 mVp and a frequency of 1 KHz is used as an input signal. The results to be observed and measured are gain, input, output and bandwidth of the bridged amplifier compared to the usual amplifier

The average deformed fiber is a continuous and smooth function of the fourth order. The deflection and rotation of beams can be determined by various methods available in the literature. Thus, in this paper, the expression of the average deformed fiber is defined in advance, then it is considered an infinite sum of sinusoidal functions that are successively evaluated using sinusoidal trigonometric series if it is considered a periodic function, or using Fourier series if it is considered a non-periodic function. The method is examined by solving several beam problems. The results indicate that the method can be used with confidence for solving any bending beam problem. [ABSTRACT FROM AUTHOR]

Unfortunately for the estimated 250 million sufferers of chronic hepatitis-B viral (HBV) infection worldwide, the liver terrain is typically ignored. An immunotolerant environment attractive for pathogens, the essential metabolic roles and structural features of the liver are aligned with distinctive gradients of oxygen and nutrients established along blood flows through fundamental hepatic processing units known as sinusoids. Capillaries surrounded by banks of hepatocytes, sinusoids express spatial configurations and concentrations of not only metabolic roles but also immune cell localisations, blood filtering and transporter specialisations: the liver terrain. HBV targets proteins regulating gluconeogenesis, a crucial liver function of blood glucose management, highly active at blood entry points--the periportal sites of sinusoids. Meanwhile, at these same sites, specialised liver macrophages, Kupffer cells (KC), aggregate and perform critical pathogen capture, detection and signaling for modulating immune responses. In tandem with KC, liver sinusoidal endothelial cells (LSECs) complement KC blood filtration and capture of pathogens as well as determine KC aggregation at the periportal sites. Failure of these systems to establish critical spatial configurations could ironically facilitate HBV invasion and entrenchment. Investigating the impacts of spatial and structural variations on the HBV infection dynamic is experimentally challenging at best. Alternatively, mathematical modeling methods provide exquisite control over said variations, permitting teasing out the subtle and competing dynamics at play within the liver terrain. Coordinating with experimental observations, multi-scale modeling methods hold promise to illuminate HBV reliance on features of the liver terrain, and potentially how it may be defeated. [ABSTRACT FROM AUTHOR]

There is no clear information on the regulation of liver blood flow by the autonomic nervous system. We conducted this study to investigate whether quiescent hepatic stellate cells (qHSCs) regulate liver blood flow in response to the sympathetic neurotransmitter norepinephrine (NE). qHSCs isolated from mice were cultured in Dulbecco's modified Eagle medium without fetal bovine serum for 1 day on collagen gel. NE-induced qHSC contraction was evaluated using the quantitative single-cell contraction measurement method that we had developed previously. For the measurement of liver perfusion pressure in situ , a buffer solution was perfused from the portal vein in mice. NE-induced a reversible contraction of qHSCs. This contraction was suppressed by the nonmuscle myosin II inhibitor blebbistatin, the myosin light chain kinase inhibitor ML-9, the Rho kinase inhibitor H-1152, the calmodulin inhibitor W-7, the store-operated calcium channel inhibitor YM-58483, and the IP 3 receptor inhibitor xestospongin C. In contrast, the transient receptor potential C channel inhibitor SKF96365 did not affect the NE-induced contraction. These results suggest that qHSCs contract in response to NE. The present study provides direct evidence for the first time that norepinephrine (NE) induces a reversible contraction of isolated single quiescent hepatic stellate cells (qHSCs) and further suggests that the NE-mediated qHSC contraction participates in the regulation of liver blood flow in vivo. [Display omitted] [ABSTRACT FROM AUTHOR]

Unfortunately for the estimated 250 million sufferers of chronic hepatitis-B viral (HBV) infection worldwide, the liver terrain is typically ignored. An immuno-tolerant environment attractive for pathogens, the essential metabolic roles and structural features of the liver are aligned with distinctive gradients of oxygen and nutrients established along blood flows through fundamental hepatic processing units known as sinusoids. Capillaries surrounded by banks of hepatocytes, sinusoids express spatial configurations and concentrations of not only metabolic roles but also immune cell localisations, blood filtering and transporter specialisations: the liver terrain. HBV targets proteins regulating gluconeogenesis, a crucial liver function of blood glucose management, highly active at blood entry points—the periportal sites of sinusoids. Meanwhile, at these same sites, specialised liver macrophages, Kupffer cells (KC), aggregate and perform critical pathogen capture, detection and signaling for modulating immune responses. In tandem with KC, liver sinusoidal endothelial cells (LSECs) complement KC blood filtration and capture of pathogens as well as determine KC aggregation at the periportal sites. Failure of these systems to establish critical spatial configurations could ironically facilitate HBV invasion and entrenchment. Investigating the impacts of spatial and structural variations on the HBV infection dynamic is experimentally challenging at best. Alternatively, mathematical modeling methods provide exquisite control over said variations, permitting teasing out the subtle and competing dynamics at play within the liver terrain. Coordinating with experimental observations, multi-scale modeling methods hold promise to illuminate HBV reliance on features of the liver terrain, and potentially how it may be defeated.

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The Cestrophorini are small katydids of Ecuador’s montane rainforest bearing a prominent awl-shaped fastigium verticis. They are unusual among Conocephalinae in lacking pre-tympanic ear chambers: their eardrums are exposed on their fore tibiae. There are presently two genera, Cestrophorus Redtenbacher, 1891 and Acanthacara Scudder, 1869. Awl-head habitat includes both climax forest and anthropogenically disturbed areas (e.g., pastures, roadsides) on lower slopes in the drainage of the volcanoes Aliso, Chiles and Tungurahua. At night, males perch on low vegetation and stridulate to attract females. To three extant species, we add a further seven, two in Cestrophorus and five in Acanthacara. Male calling songs were recorded and analyzed for all three Cestrophorus species and for three of the Acanthacara spp. We describe and discuss the waveforms of their sinusoid and transient sound pulses in time and frequency domains. [ABSTRACT FROM AUTHOR]

Abstract Purpose Erectile dysfunction (ED) is one of the increasing diseases with aging society. The basis of ED derived from local penile abnormality is poorly understood because of the complex three‐dimensional (3D) distribution of sinusoids in corpus cavernosum (CC). Understanding the 3D histological structure of penis is thus necessary. Analyses on the status of regulatory signals for such abnormality are also performed. Methods To analyze the 3D structure of sinusoid, 3D reconstruction from serial sections of murine CC were performed. Histological analyses between young (2 months old) and aged (14 months old) CC were performed. As for chondrogenic signaling status of aged CC, SOX9 and RBPJK staining was examined. Results Sinusoids prominently developed in the outer regions of CC adjacent to tunica albuginea. Aged CC samples contained ectopic chondrocytes in such regions. Associating with the appearance of chondrocytes, the expression of SOX9, chondrogenic regulator, was upregulated. The expression of RBPJK, one of the Notch signal regulators, was downregulated in the aged CC. Conclusions Prominent sinusoids distribute in the outer region of CC which may possess important roles for erection. A possibility of ectopic chondrogenesis induced by alteration of SOX9/Notch signaling with aging is indicated.

We introduce in this paper an application developed in the Python programming language that can be used to generate digital signals with known frequencies and amplitudes. These digital signals, since have known parameters, can be used to create benchmarks for test and numerical simulation.

The average deformed fiber is a continuous and smooth function of the fourth order. The deflection and rotation of beams can be determined by various methods available in the literature. Thus, in this paper, the expression of the average deformed fiber is defined in advance, then it is considered an infinite sum of sinusoidal functions that are successively evaluated using sinusoidal trigonometric series if it is considered a periodic function, or using Fourier series if it is considered a non-periodic function. The method is examined by solving several beam problems. The results indicate that the method can be used with confidence for solving any bending beam problem.

Sinusoidal obstruction syndrome (SOS) is a unique form of liver injury that occurs after exposure to chemotherapeutic drugs and toxins. The diagnosis of SOS in humans remains a challenge as the clinical criteria have low specificity and there are no reliable noninvasive biomarkers. The mechanism of injury is believed to be damage to liver endothelial cells, primarily sinusoidal endothelial cells (SECs), which leads to sinusoidal dilation, central venous fibrosis, and/or nodular regeneration. Nonclinical data suggest that this uncommon liver toxicity can be recapitulated in cynomolgus monkeys, and it is critical that pathologists are familiar with its characteristic clinicopathologic features. Elevations in liver enzymes, in particular aspartate aminotransferase, associated with isolated thrombocytopenia, should raise the suspicion of SEC injury for specific drug classes. Characterization of liver microscopic findings in monkeys benefits from the use of appropriate stains, such as reticulin stain, and VEGFR2 and CD34 immunohistochemical (IHC) stains. CD41 IHC demonstrates platelet accumulation in injured sinusoids, the likely cause of thrombocytopenia commonly reported in SOS. In conclusion, this report provides a comprehensive characterization of the pathology findings of drug-induced SOS in monkeys with the objectives of ensuring appropriate nonclinical recognition of the liability and informing clinical development strategy and monitoring. [ABSTRACT FROM AUTHOR]

The aim of this review is to give an outline of the blood clearance function of the liver sinusoidal endothelial cells (LSECs) in health and disease. Lining the hundreds of millions of hepatic sinusoids in the human liver the LSECs are perfectly located to survey the constituents of the blood. These cells are equipped with high-affinity receptors and an intracellular vesicle transport apparatus, enabling a remarkably efficient machinery for removal of large molecules and nanoparticles from the blood, thus contributing importantly to maintain blood and tissue homeostasis. We describe here central aspects of LSEC signature receptors that enable the cells to recognize and internalize blood-borne waste macromolecules at great speed and high capacity. Notably, this blood clearance system is a silent process, in the sense that it usually neither requires or elicits cell activation or immune responses. Most of our knowledge about LSECs arises from studies in animals, of which mouse and rat make up the great majority, and some species differences relevant for extrapolating from animal models to human are discussed. In the last part of the review, we discuss comparative aspects of the LSEC scavenger functions and specialized scavenger endothelial cells (SECs) in other vascular beds and in different vertebrate classes. In conclusion, the activity of LSECs and other SECs prevent exposure of a great number of waste products to the immune system, and molecules with noxious biological activities are effectively “silenced” by the rapid clearance in LSECs. An undesired consequence of this avid scavenging system is unwanted uptake of nanomedicines and biologics in the cells. As the development of this new generation of therapeutics evolves, there will be a sharp increase in the need to understand the clearance function of LSECs in health and disease. There is still a significant knowledge gap in how the LSEC clearance function is affected in liver disease.

The aim of this review is to give an outline of the blood clearance function of the liver sinusoidal endothelial cells (LSECs) in health and disease. Lining the hundreds of millions of hepatic sinusoids in the human liver the LSECs are perfectly located to survey the constituents of the blood. These cells are equipped with high-affinity receptors and an intracellular vesicle transport apparatus, enabling a remarkably efficient machinery for removal of large molecules and nanoparticles from the blood, thus contributing importantly to maintain blood and tissue homeostasis. We describe here central aspects of LSEC signature receptors that enable the cells to recognize and internalize blood-borne waste macromolecules at great speed and high capacity. Notably, this blood clearance system is a silent process, in the sense that it usually neither requires or elicits cell activation or immune responses. Most of our knowledge about LSECs arises from studies in animals, of which mouse and rat make up the great majority, and some species differences relevant for extrapolating from animal models to human are discussed. In the last part of the review, we discuss comparative aspects of the LSEC scavenger functions and specialized scavenger endothelial cells (SECs) in other vascular beds and in different vertebrate classes. In conclusion, the activity of LSECs and other SECs prevent exposure of a great number of waste products to the immune system, and molecules with noxious biological activities are effectively "silenced" by the rapid clearance in LSECs. An undesired consequence of this avid scavenging system is unwanted uptake of nanomedicines and biologics in the cells. As the development of this new generation of therapeutics evolves, there will be a sharp increase in the need to understand the clearance function of LSECs in health and disease. There is still a significant knowledge gap in how the LSEC clearance function is affected in liver disease. [ABSTRACT FROM AUTHOR]

Summary: In 1929, Fisher proposed a test for periodicity based on the largest periodogram ordinate. If the true frequency lies between two consecutive Fourier frequencies and the signal to noise ratio is low, the test may conclude that there is no periodicity. This loss of power was noted by Whittle in 1952, as well as the necessary assumption that the noise be white. Whittle and subsequent authors suggested remedies for the white noise assumption. This paper proposes simple tests, based on the Fourier coefficients, that is, the Fourier transforms at the Fourier frequencies, that have good power properties at all frequencies. [ABSTRACT FROM AUTHOR]

In this article, a photonic technique is proposed for generating the microwave signal of multiple shapes. Furthermore, this is modified to give a microwave signal with frequency multiplying capability, which does not require an optical filter. The proposed methodology is relied on the polarization modulator (PM), the Mach-Zehnder modulator (MZM), and the variable optical delay line (VODL), where the transmission point of PM has been selected by static phase of polarizer controller and MZM by the dc bias voltage. An RF signal of 6-GHz frequency is applied at PM to modulate the optical carrier signal. Frequency-dependent VODL has been used to provide dynamic phase shifts in the harmonics of the modulated signal. Firstly, 12-GHz full-wave rectified (FWR) and 6-GHz half-wave rectified (HWR) sinusoidal signals have been generated using PM and VODL. For the generation of FWR and HWR, respective phase shifts of −π/2 and π have been introduced by VODL. Then, a sextupled microwave signal of 36-GHz frequency has been generated which is further processed for the generation of triangular-shaped HWR of 6-GHz frequency. This has been achieved by modulating one of the split powers of PM with the help of an MZM. The generation of such multishape rectified waveforms has not been reported before. Also, the frequency sextupling capability of the proposed technique defines the multifunctionality of the system. Theoretical analysis of the considered approach has been given which is supported by simulated results and validated by the experimental results. [ABSTRACT FROM AUTHOR]

Eden vodilnih ameriško-ruskih

Purpose: Erectile dysfunction (ED) is one of the increasing diseases with aging society. The basis of ED derived from local penile abnormality is poorly understood because of the complex three‐dimensional (3D) distribution of sinusoids in corpus cavernosum (CC). Understanding the 3D histological structure of penis is thus necessary. Analyses on the status of regulatory signals for such abnormality are also performed. Methods: To analyze the 3D structure of sinusoid, 3D reconstruction from serial sections of murine CC were performed. Histological analyses between young (2 months old) and aged (14 months old) CC were performed. As for chondrogenic signaling status of aged CC, SOX9 and RBPJK staining was examined. Results: Sinusoids prominently developed in the outer regions of CC adjacent to tunica albuginea. Aged CC samples contained ectopic chondrocytes in such regions. Associating with the appearance of chondrocytes, the expression of SOX9, chondrogenic regulator, was upregulated. The expression of RBPJK, one of the Notch signal regulators, was downregulated in the aged CC. Conclusions: Prominent sinusoids distribute in the outer region of CC which may possess important roles for erection. A possibility of ectopic chondrogenesis induced by alteration of SOX9/Notch signaling with aging is indicated. [ABSTRACT FROM AUTHOR]

Visceral leishmaniasis (VL) is the most severe form of leishmaniasis caused by protozoan parasites of the genus Leishmania. Hepatomegaly is one of the most frequent clinical manifestations of VL, whereas immunopathology of the symptom has not been well investigated. Using our chronic model of experimental VL, we examined the influence of Leishmania donovani infection on the liver by clinical, histological, and biochemical analyses. The infected mice showed increased liver weight 24 weeks post-infection. Although an increase in serum ALT and inflammatory cell accumulation were observed in the livers of infected mice, no apparent parenchymal necrosis or fibrosis was observed. Tissue water content analyses demonstrated that increased liver weight was predominantly due to an increase in water weight. Together with the finding of hepatic sinusoidal dilation, these results suggested that edema associated with sinusoidal dilation causes hepatomegaly in L. donovani infection. Immunostaining of platelets and erythrocytes showed no thrombus formation or damage to the sinusoidal endothelium in the liver of infected mice. Taken together, these results suggest that hepatomegaly during experimental VL is caused by non-obstructive sinusoidal dilation.

We introduce in this paper an application developed in the Python programming language that can be used to generate digital signals with known frequencies and amplitudes. These digital signals, since have known parameters, can be used to create benchmarks for test and numerical simulation. [ABSTRACT FROM AUTHOR]

Hematopoietic stem cells (HSCs) exist in a close contact with their specific microenvironment, called a niche, which supports the HSC function and significantly influences the HSC properties. The existence of the HSC niche, which was proposed as a purely theoretical concept in 1978, finds increasing experimental evidence and is now generally accepted by specialists in the field of hematopoiesis. The review briefly describes various cell components of the HSC niche in bone marrow, considers the metabolic states of the niche and HSCs, and discusses other aspects of niche biology. Increasing knowledge of the HSC niche will help to create in vitro cell models of the HSC niche, to modulate the HSC properties, and to achieve multifold HSC expansion in culture for further applications in therapeutic practice. [ABSTRACT FROM AUTHOR]

In this paper, a novel multiscale amplitude feature is proposed using multiresolution analysis (MRA) and the significance of the vocal tract is investigated for emotion classification from the speech signal. MRA decomposes the speech signal into number of sub-band signals. The proposed feature is computed by using sinusoidal model on each sub-band signal. Different emotions have different impacts on the vocal tract. As a result, vocal tract responds in a unique way for each emotion. The vocal tract information is enhanced using pre-emphasis. Therefore, emotion information manifested in the vocal tract can be well exploited. This may help in improving the performance of emotion classification. Emotion recognition is performed using German emotional EMODB database, interactive emotional dyadic motion capture database, simulated stressed speech database, and FAU AIBO database with speech signal and speech with enhanced vocal tract information (SEVTI). The performance of the proposed multiscale amplitude feature is compared with three different types of features: 1) the mel frequency cepstral coefficients; 2) the Teager energy operator (TEO)-based feature (TEO-CB-Auto-Env); and 3) the breathinesss feature. The proposed feature outperforms the other features. In terms of recognition rates, the features derived from the SEVTI signal, give better performance compared to the features derived from the speech signal. Combination of the features with SEVTI signal shows average recognition rate of 86.7% using EMODB database. [ABSTRACT FROM AUTHOR]

This paper proposes methods to generate various types of Linear Voltage Transfer Curves (VTC) using Operational Trans-Resistance Amplifier (OTRA) as the active block. It further goes on to propose methods to multiplex various individual Linear VTCs to obtain any form of Piece-Wise Linear Voltage Transfer Curves (PWL), which find many applications in the world of circuitry. One particular application has been highlighted, i.e. generation of High-Frequency Sinusoids. Simulations of the Circuits proposed via Cadence Virtuoso, using TowerJazz’s 180 nm Technology Node have been reported, which satisfy the aim behind its development.

The article focuses on certain elements of J.S. Bach's handwritten musical notation, and in particular on his sinusoidal form of beaming in groups of eighths. Bach's later manuscripts typically display an increasing use of descending sinusoids implemented by flexion movement of the wrist, indicating disturbance to the blood supply to the brain. This identifiable trait of Bach's handwriting negates the traditional view that the engraver of the bifolio with canons and the Fuga canonica from the Musical Offering was Johann Heinrich Schübler, and instead enables attribution of the preparation of its engraving copy (Abklatschvorlage) to J.S. Bach himself. [ABSTRACT FROM AUTHOR]

Maintenance of the complex phenotype of primary hepatocytes in vitro represents a limitation for developing liver support systems and reliable tools for biomedical research and drug screening. We herein aimed at developing a biosystem able to preserve human and rodent hepatocytes phenotype in vitro based on the main characteristics of the liver sinusoid: unique cellular architecture, endothelial biodynamic stimulation, and parenchymal zonation. Primary hepatocytes and liver sinusoidal endothelial cells (LSEC) were isolated from control and cirrhotic human or control rat livers and cultured in conventional in vitro platforms or within our liver‐resembling device. Hepatocytes phenotype, function, and response to hepatotoxic drugs were analyzed. Results evidenced that mimicking the in vivo sinusoidal environment within our biosystem, primary human and rat hepatocytes cocultured with functional LSEC maintained morphology and showed high albumin and urea production, enhanced cytochrome P450 family 3 subfamily A member 4 (CYP3A4) activity, and maintained expression of hepatocyte nuclear factor 4 alpha (hnf4α) and transporters, showing delayed hepatocyte dedifferentiation. In addition, differentiated hepatocytes cultured within this liver‐resembling device responded to acute treatment with known hepatotoxic drugs significantly different from those seen in conventional culture platforms. In conclusion, this study describes a new bioengineered device that mimics the human sinusoid in vitro, representing a novel method to study liver diseases and toxicology. A new bioengineered device that mimics the human liver sinusoid is presented. The device represents a new tool for biomedical research on liver disease and toxicology. [ABSTRACT FROM AUTHOR]

Hepatic sinusoidal dilatation refers to the enlargement of the hepatic capillaries. Most of the time this condition is caused by hepatic venous outflow obstruction, which results in vascular stasis and congestion of hepatic parenchyma. In this setting, hepatic sinusoidal dilatation can be related to pericardial disease, heart failure, compression or thrombosis of the hepatic veins or inferior vena cava (i.e., Budd-Chiari syndrome) or central veins/sinusoids involvement (i.e., sinusoidal obstruction syndrome). Nevertheless, some extrahepatic inflammatory conditions (such as pyelonephritis, cholecystitis, pneumonia, pancreatitis, intestinal bowel disease, and others) may be associated with hepatic sinusoidal dilatation without concurrent venous outflow obstruction. On contrast-enhanced cross-sectional imaging, hepatic sinusoidal dilatation is typically characterized by a mottled, reticular enhancement of the liver, usually referred to as “mosaic” pattern. Other hepatic and extrahepatic imaging features, such us the dilatation of the hepatic veins or the presence of ascites, can help in identifying the cause of sinusoidal dilatation. [ABSTRACT FROM AUTHOR]

A frequency estimator of sinusoid based on interpolation of three discrete Fourier transform (DFT) spectral lines is proposed. The FFT is performed first on the sampled sinusoid signal and the coarse frequency estimation is made by searching the location of the discrete spectral line with maximum amplitude (the primary spectral line). Fine frequency estimation is made by the interpolation using the primary spectral line and two auxiliary spectral lines located at arbitrary position within the main lobe or the first sidelobe of the frequency spectrum. The formula for calculating the MSE of the proposed estimator in additive white noise is derived. The influence of the interval between the primary spectral line and the auxiliary spectral lines on the MSE is analyzed through theoretical analysis and simulation experiments. To further improve the estimation performance, iterative procedures are used. Simulation results show that the RMSE of the proposed estimator is closer to CRLB than the competing estimators especially at high SNR. [ABSTRACT FROM AUTHOR]

Background and aims: The liver during fetogenesis does not follow classical lobular pattern. Normal histology of the fetal liver at various stages of development was studied to get insight into the morphology of fetal liver and special function it performs in fetal life. Method: Dissection of 29 normal human fetuses was done and histological findings of liver were noted with respect to the age of fetus. The histology of fetal liver was studied using H & E stain and important features of fetal liver were studied. Result: Fetal liver histology is different from adult liver. Unlike adult liver, fetal liver shows hepatocytes arranged in sheets predominantly with cordlike pattern at places. The sinusoids are dilated and filled with hemopoietic cells, which could be appreciated at different stages of fetal development. The Kupffer cells were also noticed in fetal liver. Conclusion: The present study will be helpful in understanding the normal histology of fetal liver and add to the existing knowledge regarding development of fetal liver.

In order to satisfy the pressing and rubbing operation effects of barking machines and simplify its mechanical structure, a curved groove ball bearing was designed. The outer ring of curved groove ball bearing was a three-dimensional sine curve circular arc raceway with a period of 7 and an amplitude of 1 mm. The inner ring of curved groove ball bearing was designed as a fixed ball hole structure. The curved groove ball bearings were installed in pairs, the center axis of the two bearings needed to be lined up properly, and its installation should be ensured the “Peak” to the “Valley”. The rotation of the inner ring was driven by spindle rotation in operation, the rolling element moved into the inner ring ball socket, at the same time, moved along the outer ring raceway. That formed gyratory motions and straight reciprocating motions of the shaft. The main structural parameters of curved groove ball bearing were as follows: outer diameter 80 mm, inner diameter 50 mm, width 16 mm, radius of outer ring raceway 5 mm, radius of spherical cavity 5.9 mm, small ball diameter in spherical cavity 1 mm, curvature radius of small ball fixed point 4.9 mm, roller diameter 9.525 mm, rolling number 7, and original contact angle 25°. The raceway of outer ring affects not only the motion characteristics of curved groove ball bearing but also its carrying capacity. The contact stress of five contact points between rolling element and peak to bottom of outer ring raceway under different loading forces was analyzed, and force analysis model of the curved groove ball bearing was established. Theoretical arithmetic results showed that the contact stress between the rolling element and the outer ring was decreased from peak to valley, and increased by the loading force. Base on theoretical analysis, curved groove ball bearing was designed. A self-made test bench was used to test the curved groove ball bearing samples. The test bench exerted a radial force upon the bearing by weight loading methods, and exerted an axial force by adjusting the amount of spring compression. A phase adjustable bearing seat was adopted on the test bench. The installation phase of the two bearings could be adjusted by nuts to ensure the synchronous movement of the two bearings and avoid the interference of the movement. The curved groove ball bearing was applied to the professional equipment of agricultural products processing and utilization, the requirements of the running speed was not too high, and considering the machining precision during the trial, therefor the test bearing was tested at a low speed. The spindle speed of test bench was controlled by frequency converter. The test bearings operated at speeds of 60 r/min. The thermocouple was attached to the bottom of the outer ring for temperature detection. The outer ring temperature rising processes were tested in the radial force 150 N under the condition of axial load for outer ring 80, 120, 160, 200 and 235 N, and in the axial force160 N under the condition of radial force for outer ring 80, 120, 160, 200 and 235 N. The self-made curved groove ball bearing is stable and reliable during the tests. The results showed that the temperature rising range of bearing outer ring with the increase of loading forces s was heightened, and the temperature rise speed was accelerated. The temperature rise curve suddenly increased in the beginning of 5 min, and reached 80% of the stable temperature rise. The temperature rise curve tends to be gentle and basically reached the thermal equilibrium state after 10 min. Our research provides the reference for the structure optimization, shaping production and subsequent application of the curved groove ball bearing. [ABSTRACT FROM AUTHOR]

Numerous papers deal with the Equivalent Plate Model (EPM) for corrugated panels. Comparison of published formulas for the four relevant equivalent bending stiffnesses D 11 eq , D 22 eq , D 66 eq , and D 12 eq revealed ambiguities: Three different formulas were found for D 22 eq , which describes the bending of the ridges and troughs; for D 66 eq two ‘competing’ formulas emerged. Expressions not converging to the flat-plate values in the limit of vanishing corrugation height were discarded. All discussed formulas are written in a uniform notation for general one-dimensionally periodic shapes. Formulas derived for isotropic panel materials were generalized to the orthotropic case. In order to resolve the ambiguities and assess the EPM with regard to its range of applicability, vibration modes of six rectangular corrugated panels were measured. While agreement with numerical results obtained with COMSOL was fair, the EPM predictions of natural frequencies were satisfactory only for low-order modes. Finally, equivalent bending stiffnesses were determined numerically from COMSOL results for a few low-order modes by inverse methods. Thus the ambiguities with regard to D 22 eq and D 66 eq could be resolved. However, the D 12 eq values determined numerically came out significantly larger than the EPM prediction, in particular for stronger corrugations. Even though this discrepancy had little effect on the natural frequencies tested in the present paper, it remains a theoretical challenge. [ABSTRACT FROM AUTHOR]