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1.
Inorg Chem ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39402967

RESUMO

We report a high nuclear (Cu14) complex synthesized via the self-assembly of copper-methylsilsesquioxane induced by the complexation with 1,2-bis(diphenylphosphino)ethane (dppe). The structure includes two cationic CuI(dppe)2 moieties and an anionic silsesquioxane cage of an unprecedented CuII12 structural type. The Cu12 cage fragment exhibits a unique (i) combination of Si4-cyclic/Si2-acyclic silsesquioxane ligands and (ii) encapsulation of two different chloride and carbonate species. This complex acts as a promising precatalyst in the mild oxidation and carboxylation of light alkanes to produce alkyl hydroperoxides, alcohols, ketones, or carboxylic acids. The present study widens the family of copper-methylsilsesquioxane clusters with prospective use in oxidation catalysis.

2.
Cureus ; 16(7): e63998, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39109117

RESUMO

A new prototype of ventilator mode, based on high-frequency ventilation (HFV), aims to address the interrelations among diverse respiratory variables, several intercardiovascular parameters rapports, and instantaneously the intrarespiratory and cardiac interactions. This article proposes a logarithmic network of integrated correlation ratio H/V, R correlation, that primarily relates both dependent respiratory (V) and independent hemodynamic variables (H). Given a constant steady state of the heart and vasculature, a difference between calculated ratio (R calc), and optimized ratio (R opt) could be utilized to adjust many aspects of several parameters and outcomes in critically ill patients. The central venous pressure (CVP) wave analysis aims to approach several cardiovascular parameters, endpoints of left atrial (LA) pressure, and the cardiac output (CO) with the help of thermodilution curve analysis. This might result in several innovative formulas of mathematical base. Their relevant clinical implicates demonstrated a wide area of normalized distribution capacity (Cd), systemic vascular capacity (Cs), pulmonary vascular capacitance (Cp), pulmonary vascular resistance (PVR), and mean pulmonary artery pressure (MPAP). The authors claim that prepared software programming helps network integration of all these variables, feeding back and addressing the prototype of novel mode for the old new application of HFV. One potential unique criterion is adjusting LA and ultimately CO through a feedback control mechanism. Though this all sounds very plausible, the reader must be reminded that everything in this work is based on the most expected speculations and experience and could be potentially different than that in vivo. More importantly, animal experimental studies are warranted.

3.
Chemistry ; 30(31): e202401164, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38551412

RESUMO

Convenient self-assembly synthesis of copper(II) complexes via double (phenylsilsesquioxane and acetate) ligation allows to isolate a family of impressive sandwich-like cage compounds. An intriguing feature of these complexes is the difference in the structure of a pair of silsesquioxane ligands despite identical (Cu6) nuclearity and number (four) of acetate fragments. Formation of particular combination of silsesquioxane ligands (cyclic/cyclic vs condensed/condensed vs cyclic/condensed) was found to be dependent on the synthesis/crystallization media. A combination of Si4-cyclic and Si6-condensed silsesquioxane ligands is a brand new feature of cage metallasilsesquioxanes. A representative Cu6-complex (4) (with cyclic silsesquioxanes) exhibited high catalytic activity in the oxidation of alkanes and alcohols with peroxides. Maximum yield of the products of cyclohexane oxidation attained 30 %. The compound 4 was also tested as catalyst in the Baeyer-Villiger oxidation of cyclohexanone by m-chloroperoxybenzoic acid: maximum yields of 88 % and 100 % of ϵ-caprolactone were achieved upon conventional heating at 50 °C for 4 h and MW irradiation at 70 or 80 °C during 30 min, respectively. It was also possible to obtain the lactone (up to 16 % yield) directly from the cyclohexane via a tandem oxidation/Baeyer-Villiger oxidation reaction using the same oxidant.

4.
J Acoust Soc Am ; 155(2): 1315-1335, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38349809

RESUMO

Ocean acoustic tomography (OAT) methods aim at estimating variations of sound speed profiles (SSP) based on acoustic measurements between multiple source-receiver pairs (e.g., eigenray travel times). This study investigates the estimation of range-dependent SSPs in the upper ocean over short ranges (<5 km) using the classical ray-based OAT formulation as well as iterative or adaptive OAT formulations (i.e., when the sources and receivers configuration can evolve across successive iterations of this inverse problem). A regional ocean circulation model for the DeSoto Canyon in the Gulf of Mexico is used to simulate three-dimensional sound speed variations spanning a month-long period, which exhibits significant submesoscale variability of variable intensity. OAT performance is investigated in this simulated environment in terms of (1) the selected source-receivers configuration and effective ray coverage, (2) the selected OAT estimator formulations, linearized forward model accuracy, and the parameterization of the expected SSP variability in terms of empirical orthogonal functions, and (3) the duration over which the OAT inversion is performed. Practical implications for the design of future OAT experiments for monitoring submesoscale variability in the upper ocean with moving autonomous platforms are discussed.

5.
Ophthalmic Plast Reconstr Surg ; 40(1): 11-17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37486339

RESUMO

PURPOSE: There is no known optimal treatment for primary periocular orofacial granulomatosis (PPOFG), a disorder that results in periocular edema. This case series and systematic review identifies management strategies and their reported improvement. METHODS: Systematic review and case series. PubMed and MEDLINE databases were searched following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines to identify published cases of PPOFG. Cases were included when edema involved the periocular tissues and when a biopsy was interpreted to be PPOFG. Cases were excluded when edema did not involve the periocular tissues or when the edema was secondary to another process. The electronic medical records of the pathology department were studied to identify cases that were in keeping with PPOFG. The clinical charts were examined to confirm the diagnosis and provide a local case series. RESULTS: There are 38 published cases of PPOFG. An additional 9 cases were identified locally. These cases were combined and analyzed. Most PPOFG has eyelid swelling in isolation, without other facial swelling (36/47; 76.6%). It is most commonly a bilateral disease (30/47; 63.8%). Fissured tongue and facial nerve palsy occur, just as they do in other cases of orofacial granulomatosis. Treatment with surgical debulking or intralesional steroids resulted in high rates of symptomatic improvement of eyelid swelling, but recurrences were common. CONCLUSIONS: In light of no curative or highly successful treatment currently available, intralesional steroids and/or surgical debulking are therapies in the treatment of eyelid swelling associated with PPOFG that demonstrate reasonable short- and medium-term results. There is no established therapy that can offer disease remission or long-term symptom improvement.


Assuntos
Paralisia Facial , Granulomatose Orofacial , Humanos , Granulomatose Orofacial/terapia , Granulomatose Orofacial/tratamento farmacológico , Edema/diagnóstico , Biópsia , Esteroides/uso terapêutico
7.
Artigo em Inglês | MEDLINE | ID: mdl-38109243

RESUMO

Autonomous underwater vehicle (AUV) operations are limited by currently achievable underwater localization and navigation solutions; hence, the development of low-cost and passive (i.e., operable without an active power supply) acoustic underwater markers (or tags) can provide accurate localization information to AUVs improving their situational awareness, especially when operating in small scales or confined missions. This work presents an acoustic identification (AID) tag that can be powered wirelessly with ultrasonic power transfer from a remote acoustic source (e.g., mounted on an interrogating AUV) and provide localization information using backscatter communication. The AID tag harvests energy from the acoustic signal generated from the AUV and communicates by modulating the reflected signals from an embedded piezoelectric transducer. A scaled broadband AID tag prototype that achieves concurrent acoustic energy harvesting (tuned around 1.3 MHz) and backscatter communication (in wider frequency band 600 and 800 kHz) using frequency-domain multiplexing is implemented using a custom broadband impedance matching-based transducer design approach. During concurrent power and data operation, this prototype AID tag achieves data rates up to 200 kb/s using amplitude- and frequency-based modulation communication. The use of broadband schemes to achieve robust communications in low SNR (tested here down to -6 dB) is also demonstrated using linear frequency-modulated data carriers. Finally, the extension to full-scale devices of this AID tag concept and potential applications for short-range AUV routing and navigation such as homing and docking are discussed.

8.
JASA Express Lett ; 3(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37962475

RESUMO

This work investigates how vertical resolution affects the prediction of ocean sound speed through a suite of regional simulations covering the DeSoto Canyon in the Gulf of Mexico. Simulations have identical horizontal resolution of 0.5 km, partially resolving submesoscale dynamics, and vertical resolution from 30 to 200 terrain-following layers. The focus is on mesoscale eddies and how modeled sound speeds vary whenever more vertical baroclinic modes are resolved. While domain-averaged sound speed profiles do not differ substantively, the standard deviation increases for increasing resolution due to the sharper representation of mesoscale circulations underneath the mixed layer and their associated density anomalies.

9.
J Genet Eng Biotechnol ; 21(1): 131, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987952

RESUMO

BACKGROUND: Breast cancer is the most significant threat to women worldwide. Most chemotherapeutic drugs cause cancer cell death and apoptosis by inducing oxidative stress and producing reactive oxygen species (ROS). Cancer cells have a higher rate of metabolic activity than normal cells and thus produce more ROS. Glutathione and its related enzymes are the most significant antioxidant defense mechanisms that protect cells from oxidative and chemotherapeutic impacts. The anticancer actions of phenolic compounds were greatly confirmed. Using phenolic compounds as drugs in combination with chemotherapy may improve health, improve treatment outcomes, and reduce dose and damage. The goal of the study was to treat breast cancer cell lines (MCF-7) with Tamarindus indica extract individually and in combination with the anticancer drug tamoxifen (TAM) to improve therapeutic efficacy. RESULTS: After 48 h of incubation at IC25 concentrations of T. indica extract (47.3 g/mL), tamoxifen (0.8 g/mL), and their co-treatments, the biochemical and genotoxic effects on MCF-7 cell lines were investigated. In MCF7 cell lines, T. indica extract increased reduced glutathione levels as well as glutathione transferase, glutathione peroxidase, and glutathione reductase activities. The same was true for oxidative state indicators, where higher levels of catalase and lactate dehydrogenase activity were associated with higher levels of malondialdehyde. T. indica has almost no effect on the DNA damage parameters. All of these variations can produce alterations in cancer cell genotoxicity and apoptotic pathways, explaining the restoration of DNA moment to normal levels and enhanced survival. CONCLUSION: Cytotoxic and genotoxic effect of treatment with T. indica extract could be attributed to the dynamic interaction of glutathione cycle and antioxidant enzymes to combat oxidative stress, which can be considered as a positive therapeutic effect. On the other hand, the negative response of tamoxifen efficacy when co-treated with T. indica reversed tamoxifen's genotoxicity and enhanced survival.

10.
J Knee Surg ; 36(7): 752-758, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35114720

RESUMO

Improper alignment and implant positioning following unicompartmental knee arthroplasty (UKA) has been shown to lead to postoperative pain and increase the incidence of revision procedures. The use of robotic-arm assistance for UKA (RAUKA) has become an area of interest to help overcome these challenges. The accuracy of intraoperative alignment compared with standing long-leg X-rays postoperatively following medial RAUKA has been in question. Therefore, the purpose of this study was to (1) determine final mean intraoperative coronal alignment in extension utilizing an image based intraoperative navigation system, and (2) compare final intraoperative alignment to 6-week weight-bearing (WB) long-leg X-rays. Patients who underwent RAUKA for medial compartmental osteoarthritis were identified from January 1, 2018, to August 31, 2019, through our institution's joint registry. The query yielded 136 (72 right and 64 left) patients with a mean age of 72.02 years and mean body mass index (BMI) of 28.65 kg/m2 who underwent RAUKA. Final intraoperative alignment was compared with WB long leg X-rays 6 weeks postoperatively by measuring the mechanical alignment. Statistical analysis was primarily descriptive. Pearson's correlation coefficient was used to determine the relationship between intraoperative alignment to 6-week alignment. A p-value of <0.05 was considered statistically significant. Mean intraoperative coronal alignment after resections and trialing was 4.39 varus ± 2.40 degrees for the right knee, and 4.81 varus ± 2.29 degrees for the left knee. WB long-leg X-rays 6 weeks postoperatively demonstrated mechanical axis alignment for the right and left knees to be 3.01 varus ± 2.10 and 3.7 varus ± 2.38 degrees, respectively. This resulted in a change in alignment of 1.36 ± 1.76 and 1.12 ± 1.84 degrees for the right and left knees, respectively (p < 0.05). Pearson's correlation coefficient demonstrated a correlation of 0.69 between intraoperative to long-leg-X-ray alignment. RAUKA demonstrates excellent consistency when comparing postoperative WB long-leg X-rays to final intraoperative image-based non-WB alignment.


Assuntos
Artroplastia do Joelho , Procedimentos Cirúrgicos Robóticos , Idoso , Humanos , Artroplastia do Joelho/métodos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Prótese do Joelho , Perna (Membro)/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos
11.
Arch Razi Inst ; 78(6): 1680-1689, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38828166

RESUMO

The present reserach aimed to detect and isolate the genes involved in the staphylococcal enterotoxins (SEs) production in strains isolated from unprocessed cow's milk and to examine the impact of Bifidobacterium bifidum probiotic cell-free supernatant (CFS) on their expression. Standard techniques were used for isolation and identification of Staphylococci strains in unprocessed milk. The PCR was used to identify strains carrying enterotoxin genes. The B. bifidum CFS was applied to strains containing the target genes, and the genes expression levels were quantified using Real-time PCR. Using 16SrDNA sequencing, the phylogenic relationship of the isolated strains was determined. Analysis revealed that bacteria such as Staphylococcus species were found in the 72% of the samples. The PCR test showed the presence of various SE superantigens, including SEA (16.7%), SEC (11.7%), SED (8.3%), SEE (6.7%), and SEB (1.7%) in isolated strains. The B. bifidum CFS had obvious antimicrobial activity against strains 24, 51, 54, and 35 of Staphylococcus species, and the minimum inhibitory concentration and minimum bactericidal concentration values for these strains treated with B. bifidum CFS were in the range of 31.25-125 µg/ml. Strains 51 and 24 were clustered with S.aureus ATCC 25923, and strains 54 and 35 were clustered with S.aureus ATCC 12600, respectively. The RT-PCR exhibited that probiotics CFS suppressed the expression of SEA, SEB, SEC, and SEE genes (P<0.05). The average fold change for SEA, SEB, SEC, and SED genes was -1.681, -1.28, -1.52, and -0.84, respectively. The research demonstrated that probiotic bacteria can lower enterotoxin production by downregulating the expression of SEs genes.


Assuntos
Bifidobacterium bifidum , Enterotoxinas , Leite , Probióticos , Staphylococcus aureus , Enterotoxinas/genética , Enterotoxinas/metabolismo , Animais , Probióticos/farmacologia , Leite/microbiologia , Bovinos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Bifidobacterium bifidum/fisiologia , Expressão Gênica
12.
J Acoust Soc Am ; 152(6): 3768, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36586825

RESUMO

Underwater sound propagation is primarily driven by a nonlinear forward model relating variability of the ocean sound speed profile (SSP) to the acoustic observations (e.g., eigenray arrival times). Ocean acoustic tomography (OAT) methods aim at reconstructing SSP variations (with respect to a reference environment) from changes of the acoustic measurements between multiple source-receiver pairs. This article investigates the performance of three different OAT methods: (1) model-based methods (i.e., classical ray-based OAT using a linearized forward model), (2) data-driven methods (such as deep learning) to directly learn the inverse model, and (3) a hybrid solution [i.e., the neural adjoint (NA) method], which combines deep learning of the forward model with a standard recursive optimization to estimate SSPs. Additionally, synthetic SSPs were generated to augment the variability of the training set. These methods were tested with modeled ray arrivals calculated for a downward refracting environment with mild fluctuations of the thermocline. Idealized towed and fixed source configurations are considered. Results indicate that merging data-driven and model-based methods can benefit OAT predictions depending on the selected sensing configurations and actual ray coverage of the water column. But ultimately, the robustness of OAT predictions depends on the dynamics of the SSP variations.

13.
J Acoust Soc Am ; 152(2): 1201, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36050171

RESUMO

Using a network of a few compact mobile underwater platforms, each equipped with a single acoustic sensor, as a distributed sensing array is attractive but requires precise positioning of each mobile sensor. However, traditional accurate underwater positioning tools rely on active acoustic sources (e.g., acoustic pingers), which implies additional hardware and operational complexity. Hence, self-localization (i.e., totally passive) methods using only acoustic sources of opportunity (such as surface vessels) for locating the mobile sensors of a distributed array appear as a simpler alternative. Existing underwater self-localization methods have mainly been developed for mobile platforms equipped with time-synchronized hydrophones and rely only on the time-differences of arrival between multiple pairwise combinations of the mobile hydrophones as inputs for a complex non-linear inversion procedure. Instead, this article introduces a self-localization method, which uses a linear least-square formulation, for two mobile time-synchronized vector sensor platforms based on their acoustic recordings of a distant surface vessel and their inertial navigation system (INS) measurements. This method can be generalized to multiple vector sensor pairs to provide additional robustness toward input parameter errors (e.g., due to a faulty INS) as demonstrated experimentally using drifting buoys with inertial vector sensors deployed ∼100 m apart in shallow water.

14.
J Acoust Soc Am ; 149(5): 3387, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34241093

RESUMO

The development of pre-deployed underwater infrastructures to aid in autonomous underwater vehicle (AUV) navigation is of keen interest, with the increased use of AUVs for undersea operations. Previous literature has introduced a class of passive underwater acoustic markers, termed acoustic identification (AID) tags [Satish, Trivett, and Sabra, J. Acoust. Soc. Am. 147(6), EL517-EL522 (2020)], which are inexpensive to construct, simple to deploy, and reflect unique engineered acoustic signatures that can be detected by an AUV instrumented with high-frequency sonar systems. An AID tag is built of multi-layer shells with different acoustic properties and thicknesses to generate a unique acoustic signature, composed of the multiple reflections created by the layer interfaces, thus akin to an "acoustic barcode." AID tags can be used as geospatial markers to highlight checkpoints in AUV trajectories or mark areas of interest underwater. This article investigates the optimization of the AID tag's design using energy based metrics and evaluates the detectability of an AID tag in the presence of interfering signals, such as clutter using matched-filter based techniques. Furthermore, experimental results of AID tags interrogated by a standard high-frequency sonar are presented to provide proof of concept of AID tag detection in a reverberant water tank.

15.
JASA Express Lett ; 1(12): 124802, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-36154381

RESUMO

A library of broadband (100-1000 Hz) channel impulse responses (CIRs) estimated between a short bottom-mounted vertical line array (VLA) in the Santa Barbara channel and selected locations along the tracks of 27 isolated transiting ships, cumulated over nine days, is constructed using the ray-based blind deconvolution algorithm. Treating this CIR library either as data-derived replica for broadband matched-field processing (MFP) or training data for machine learning yields comparable ranging accuracy (∼50 m) for nearby vessels up to 3.2 km for both methods. Using model-based replica of the direct path only computed for an average sound-speed profile comparatively yields∼110 m ranging accuracy.


Assuntos
Acústica , Navios , Movimento (Física) , Som , Espectrografia do Som
16.
J Knee Surg ; 34(7): 772-776, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31820430

RESUMO

A common patient concern after total knee arthroplasty (TKA) is the ability to kneel. Kneeling may have a substantial impact on the patients' ability to perform many activities of daily living, occupations, and hobbies. The purpose of this study was to quantify the percentage of patients able to kneel after TKA after 2 years and to evaluate preoperative patient characteristics that influence the patient's perceived ability to kneel after TKA such as obesity, occupation, and hobbies. We retrospectively assessed a cohort of 404 patients who underwent primary TKA with patellar resurfacing. We assessed the impact of patient hobbies, occupation, employment status, and body mass index (BMI) on the kneeling capacity and patient-reported satisfaction. Univariate analysis was performed using Fisher's exact test, and multivariate analysis was performed using logistic regression with multiple imputations. A total of 404 patients were included. Sixty percent of patients were unable to kneel after TKA. Males (p < 0.001) and patients with occupations or hobbies requiring kneeling (p < 0.05) were more likely to kneel after surgery. We identified an inverse relationship between BMI and the ability to kneel. No correlation was found between duration and frequency of kneeling relative to patient-reported ease or difficulty with kneeling. Patient-reported factors that prevented patients from kneeling were pain, physical inability, and fear of damaging the prosthesis. Patient education may be helpful in improving patient expectations about kneeling after surgery. A small but significant difference in subjective patient satisfaction was observed when comparing patients able to kneel with those unable to kneel.


Assuntos
Atividades Cotidianas , Artroplastia do Joelho/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos de Coortes , Feminino , Passatempos , Humanos , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Ocupações , Dor , Patela/cirurgia , Satisfação do Paciente , Postura , Amplitude de Movimento Articular , Estudos Retrospectivos
17.
Curr Diab Rep ; 20(11): 57, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32984918

RESUMO

PURPOSE OF REVIEW: Type 2 diabetes (T2D) and obesity are comorbidities that generally progress with time even when non-invasive therapies are prescribed. Indeed, weight loss that is achieved with behavioral modification alone is generally inconsistent and often short-lived. In contrast, although patients do experience weight regain with metabolic surgery, they still benefit from a significant net decrease in weight. As a result, T2D remission can be achieved in up to 60% of patients within 2 years after surgery. However, it is unknown if the positive effects of metabolic surgery extend to macrovascular disease risk reduction. RECENT FINDINGS: As noted in four randomized controlled trials (RCTs), Roux-en-Y gastric bypass (RYGB) facilitates partial remission of T2D in about 30% of volunteers 5 years after surgery. Of the four RCTs, only one investigated the effects of sleeve gastrectomy (SG) at 5 years; that study found that the rate of partial relapse was slightly lower with SG (23%). However, observational studies indicate that the gap between RYGB and SG may be larger than that observed in RCTs. In contrast, the rate of full remission is noted infrequently 5 years after SG or RYGB. Metabolic surgery also mitigates macrovascular disease risk as indicated by multiple observational studies. The effects of metabolic surgery on cardiometabolic parameters are clinically meaningful. The weight loss that is facilitated by metabolic surgery reduces the metabolic and inflammatory stress caused by T2D and obesity. In turn, metabolic surgery likely mitigates macrovascular disease risk. Additional evidence from RCTs is needed to substantiate the effects of metabolic surgery on macrovascular disease risk.


Assuntos
Diabetes Mellitus Tipo 2 , Derivação Gástrica , Obesidade Mórbida , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia , Gastrectomia , Humanos , Obesidade/complicações , Obesidade/cirurgia , Obesidade Mórbida/cirurgia , Resultado do Tratamento
18.
J Acoust Soc Am ; 147(6): EL517, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32611164

RESUMO

A class of passive acoustic identification (AID) tags with curved symmetry for underwater navigation is presented. These AID tags are composed of radially stratified shells designed to backscatter a unique specular reflection pattern independent of the incidence orientation in a monostatic configuration, thus acting as acoustic bar-codes. The AID tag's response can be uniquely engineered by selecting the thicknesses and material properties of the individual constitutive shells. Furthermore, in the high-frequency regime, the specular component of the AID tag's response can be simply predicted numerically assuming horizontally stratified layers. This approach is demonstrated using scaled experiments with an AID tag constructed from 3D printed hemispherical shells.

19.
J Acoust Soc Am ; 147(3): 1927, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32237794

RESUMO

The ray-based blind deconvolution (RBD) technique for ocean waveguides estimates both the unknown waveform radiated by some source of opportunity and the channel impulse response (CIR) between the source and the receiving elements of an array of hydrophones using only measured signals, knowledge of the array geometry, and the local sound speed. Previous studies have investigated the applicability of this method for shipping sources in a shallow, nearly range-independent waveguide (∼200 m depth), but using a limited set of shipping vessels (typically only the research vessel itself) and operating within a small domain of RBD processing parameters (e.g., integration time and frequency band). This study systematically investigates the performance of the RBD method for estimating the CIR for a large set of shipping vessels recorded on short aperture, bottom-mounted, vertical arrays deployed in the Santa Barbara channel across different frequency bands and integration times, and also in comparison to CIR measured using active sources. Furthermore, the influence of the source motion on the RBD algorithm is quantified both numerically and experimentally.

20.
Biomolecules ; 10(4)2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235466

RESUMO

We examined the effect of mild hyperglycemia on high-density lipoprotein (HDL) metabolism and kinetics in diet-controlled subjects with type 2 diabetes (T2D). 2H2O-labeling coupled with mass spectrometry was applied to quantify HDL cholesterol turnover and HDL proteome dynamics in subjects with T2D (n = 9) and age- and BMI-matched healthy controls (n = 8). The activities of lecithin-cholesterol acyltransferase (LCAT), cholesterol ester transfer protein (CETP), and the proinflammatory index of HDL were quantified. Plasma adiponectin levels were reduced in subjects with T2D, which was directly associated with suppressed ABCA1-dependent cholesterol efflux capacity of HDL. The fractional catabolic rates of HDL cholesterol, apolipoprotein A-II (ApoA-II), ApoJ, ApoA-IV, transthyretin, complement C3, and vitamin D-binding protein (all p < 0.05) were increased in subjects with T2D. Despite increased HDL flux of acute-phase HDL proteins, there was no change in the proinflammatory index of HDL. Although LCAT and CETP activities were not affected in subjects with T2D, LCAT was inversely associated with blood glucose and CETP was inversely associated with plasma adiponectin. The degradation rates of ApoA-II and ApoA-IV were correlated with hemoglobin A1c. In conclusion, there were in vivo impairments in HDL proteome dynamics and HDL metabolism in diet-controlled patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Dieta/efeitos adversos , Lipoproteínas HDL/metabolismo , Proteômica , Adiponectina/sangue , Adulto , Idoso , Estudos de Casos e Controles , Proteínas de Transferência de Ésteres de Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Feminino , Humanos , Cinética , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Fosfatidilcolina-Esterol O-Aciltransferase/sangue , Fatores de Tempo
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