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1.
Rom J Morphol Embryol ; 65(2): 203-208, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39020534

RESUMO

Acute lymphoblastic leukemia (ALL) is the most common type of leukemia in childhood and rare in adults, while acute myeloid leukemia (AML) is less common in children and more common in older adults. The aim of the study was to present our experience for the diagnostic of leukemia by using the classic and molecular cytogenetic methods. The study was conducted between 2009 and 2019 within the Classic and Molecular Genetic Laboratory of the Oncohematology Department from the Louis Turcanu Emergency Hospital for Children, Timisoara, Romania. The study group included 337 children and adults, evaluated between 2009 and 2019. By using the conventional and molecular cytogenetic technique, the cytogenetic anomalies found were 35 numerical chromosomal abnormalities, 10 (9;22)(q34;q11) [four ALL, one AML, five chronic myeloid leukemia (CML)] translocations, nine (15;17)(q24;q21) translocations, three (14;14)(q11;q32) translocations, two (4;11)(q21;q23) translocations, one (1;14)(p32;q11) translocation, one (7;14)(qter;q11) translocation, one (8;21)(q22;q22) translocation, one (9;14)(p12;q32) translocation, seven rearrangements of the MLL gene and two rearrangements of the core-binding factor subunit beta∕myosin heavy chain 11 (CBFB∕MYH11) gene. The use of conventional and molecular cytogenetic analysis is one of the most important prognostic indicators in acute leukemia patients, allowing the identification of biologically distinct subtypes of disease and selection of appropriate treatment approaches.


Assuntos
Leucemia , Humanos , Romênia , Feminino , Masculino , Adulto , Criança , Adolescente , Pré-Escolar , Leucemia/genética , Leucemia/patologia , Leucemia/diagnóstico , Análise Citogenética/métodos , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Aberrações Cromossômicas , Lactente
2.
Diving Hyperb Med ; 52(4): 237-244, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36525681

RESUMO

INTRODUCTION: Faults or errors during use of closed-circuit rebreathers (CCRs) can cause hypoxia. Military aviators face a similar risk of hypoxia and undergo awareness training to determine their 'hypoxia signature', a personalised, reproducible set of symptoms. We aimed to establish a hypoxia signature among divers, and to investigate their ability to detect hypoxia and self-rescue while cognitively overloaded. METHODS: Eight CCR divers and 12 scuba divers underwent an initial unblinded hypoxia exposure followed by three trials; a second hypoxic trial and two normoxic trials in randomised order. Hypoxia was induced by breathing on a CCR with no oxygen supply. Subjects pedalled on a cycle ergometer while playing a neurocognitive computer game to simulate real world task loading. Subjects identified hypoxia symptoms by pointing to a board listing common hypoxia symptoms, and were instructed to perform a 'bailout' procedure to mimic self-rescue if they perceived hypoxia. Divers were prompted to bailout if peripheral oxygen saturation fell to 75%, or after six minutes during normoxic trials. Subsequently we interviewed subjects to determine their ability to distinguish hypoxia from normoxia. RESULTS: Ninety-five percent of subjects (19/20) showed agreement between unblinded and blinded hypoxia symptoms. Subjects correctly identified the gas mixture in 85% of the trials. During unblinded hypoxia, only 25% (5/20) of subjects performed unprompted bailout. Fifty-five percent of subjects (11/20) correctly performed the bailout but only when prompted, while 15% (3/20) were unable to bailout despite prompting. During blinded hypoxia 45% of subjects (9/20) performed the bailout unprompted while 15% (3/20) remained unable to bailout despite prompting. CONCLUSIONS: Although our data support a normobaric hypoxia signature among both CCR and scuba divers under experimental conditions, most subjects were unable to recognise hypoxia in real time and perform a self-rescue unprompted, although this improved in the second hypoxia trial. These results do not support hypoxia exposure training for CCR divers.


Assuntos
Mergulho , Humanos , Hipóxia , Respiração
3.
Materials (Basel) ; 15(17)2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36079515

RESUMO

The use of Fe films as multi-element targets in space radiation experiments with high-intensity ultrashort laser pulses requires a surface structure that can enhance the laser energy absorption on target, as well as a low concentration and uniform distribution of light element contaminants within the films. In this paper, (110) preferred orientation nanocrystalline Fe thin films with controlled morphology and composition were grown on (100)-oriented Si substrates by oblique angle RF magnetron sputtering, at room temperature. The evolution of films key-parameters, crucial for space-like radiation experiments with organic material, such as nanostructure, morphology, topography, and elemental composition with varying RF source power, deposition pressure, and target to substrate distance is thoroughly discussed. A selection of complementary techniques was used in order to better understand this interdependence, namely X-ray Diffraction, Atomic Force Microscopy, Scanning and Transmission Electron Microscopy, Energy Dispersive X-ray Spectroscopy and Non-Rutherford Backscattering Spectroscopy. The films featured a nanocrystalline, tilted nanocolumn structure, with crystallite size in the (110)-growth direction in the 15-25 nm range, average island size in the 20-50 nm range, and the degree of polycrystallinity determined mainly by the shortest target-to-substrate distance (10 cm) and highest deposition pressure (10-2 mbar Ar). Oxygen concentration (as impurity) into the bulk of the films as low as 1 at. %, with uniform depth distribution, was achieved for the lowest deposition pressures of (1-3) × 10-3 mbar Ar, combined with highest used values for the RF source power of 125-150 W. The results show that the growth process of the Fe thin film is strongly dependent mainly on the deposition pressure, with the film morphology influenced by nucleation and growth kinetics. Due to better control of film topography and uniform distribution of oxygen, such films can be successfully used as free-standing targets for high repetition rate experiments with high power lasers to produce Fe ion beams with a broad energy spectrum.

4.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806023

RESUMO

This review article explores the telocytes' roles in inflammatory bowel diseases (IBD), presenting the mechanisms and hypotheses related to epithelial regeneration, progressive fibrosis, and dysmotility as a consequence of TCs' reduced or absent number. Based on the presented mechanisms and hypotheses, we aim to provide a functional model to illustrate TCs' possible roles in the normal and pathological functioning of the digestive tract. TCs are influenced by the compression of nearby blood vessels and the degree of fibrosis of the surrounding tissues and mediate these processes in response. The changes in intestinal tube vascularization induced by the movement of the food bowl, and the consequent pH changes that show an anisotropy in the thickness of the intestinal tube wall, have led to the identification of a pattern of intestinal tube development based on telocytes' ability to communicate and modulate surrounding cell functions. In the construction of the theoretical model, given the predictable occurrence of colic in the infant, the two-layer arrangement of the nerve plexuses associated with the intestinal tube was considered to be incompletely adapted to the motility required with a diversified diet. There is resulting evidence of possible therapeutic targets for diseases associated with changes in local nerve tissue development.


Assuntos
Doenças Inflamatórias Intestinais , Telócitos , Fibrose , Humanos , Doenças Inflamatórias Intestinais/patologia , Telócitos/patologia
5.
Sci Rep ; 12(1): 1690, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35105901

RESUMO

We present a miniaturised thermal acoustic gas sensor, fabricated using a CMOS microhotplate and MEMS microphone. The sensing mechanism is based on the detection of changes in the thermal acoustic conversion efficiency which is dependent on the physical properties of the gas. An active sensing element, consisting of a MEMS microphone, is used to detect the target gas while a reference element is used for acoustic noise compensation. Compared to current photoacoustic gas sensors, our sensor requires neither the use of gas-encapsulated microphones, nor that of optical filters. In addition, it has all the benefits of CMOS technology, including production scalability, low cost and miniaturization. Here we demonstrate its application for CO[Formula: see text] gas detection. The sensor could be used for gas leak detection, for example, in an industrial plant.

6.
Chirurgia (Bucur) ; 116(6): 737-747, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34967718

RESUMO

Introduction: Abdominal injuries are responsible for approximately 20% of all post-traumatic deaths, 45-50% of which occurring in the first 60 minutes. Currently there are several prediction scores for the evolution of these patients, which take into account degrees of anatomical lesion, clinical signs and imaging and paraclinical explorations. AIM: The aim of the study was to develop a scoring system to predict mortality in patients with abdominal trauma by using the usual biological parameters. METHOD: A retrospective, descriptive, correlational and non-interventional multicenter study was performed on a sample of 157 patients with abdominal traumata, hospitalized between 2015- 2021, in the General Surgery and the Emergency III clinics of the Emergency University Hospital Bucharest, respectively in the Surgery I Clinic of the Mures County Emergency Clinical Hospital. The following biochemical parameters were analyzed: hemoglobin, hematocrit, leukocyte and platelet counts, coagulogram, glycemia, urea, creatinine, AST, ALT with the intent to have the correlation with the ISS and NISS mortality and traumatic scores. Microsoft Excel and MedCalc applications were used for the statistical analysis of the data. Results: The studied sample presented a sex ratio M:F = 2.82:1, the mean age was 47.45 +- 17.37 years. The elements that presented a correlation with a value greater than 0.3 (and p 0.01) were: age, ALT, AST, urea, hemoglobin, platelet count and glycemia. The cut-off values for these parameters in reference to mortality were established by analyzing the ROC curves. This fact allowed the outline of a predictive score that correlates well with the value of ISS and NISS, the obtained ROC curve using as parameters the value of the proposed risk score and mortality highlighting a good predictive power of the mortality with an AUC of 0.930 (p 0.001). CONCLUSION: The results of our study showed that a number of biochemical parameters may contribute to shaping a score with predictive value in terms of the evolution of abdominal trauma patients.


Assuntos
Traumatismos Abdominais , Ferimentos e Lesões , Traumatismos Abdominais/diagnóstico , Traumatismos Abdominais/cirurgia , Adulto , Humanos , Escala de Gravidade do Ferimento , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Estudos Retrospectivos , Resultado do Tratamento , Ferimentos e Lesões/diagnóstico
7.
J Clin Med ; 10(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34945118

RESUMO

BACKGROUND: Faecal microbiota transplant (FMT) is a highly effective therapy for recurrent Clostridioides difficile infection (rCDI) with cure rates ranging between 85 and 92%. The FMT role for primary Clostridioides difficile infection (CDI) has yet to be settled because of limited data and small-sample studies presented in the current literature. Our study goals were to report the risk factors and the risk of recurrence after FMT for each CDI episode (first, second, and third) and to explore if there is a role of FMT in primary severe CDI. METHODS: We conducted a retrospective study to analyze the clinical characteristics and the outcomes of 96 FMT patients with a prior 10 day course of antibiotic treatment in the medical records, of which 71 patients with recurrent CDI and 25 patients with a primary CDI. RESULTS: The overall primary cure rate in our study was 88.5% and the primary cure rate for the severe forms was 85.7%. The data analysis revealed 5.25%, 15.15%, and 27.3% FMT recurrence rates for primary, secondary, and tertiary severe CDI. The risk of recurrence was significantly associated with FMT after the second and the third CDI severe episodes (p < 0.05), but not with FMT after the first severe CDI episode. CONCLUSIONS: This study brings new data in supporting the FMT role in CDI treatment, including the primary severe CDI, however, further prospective and controlled studies on larger cohorts should be performed in this respect.

8.
Undersea Hyperb Med ; 48(4): 409-416, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34847304

RESUMO

Critically ill patients needing mechanical ventilation may require hyperbaric oxygen therapy. Some institutions still use ventilators that were available prior to the advent of hyperbaric-specific units, such as the Uni-Vent Eagle™ Model model 754. Here we examine the performance of the Uni-Vent model 754 under hyperbaric conditions and investigate concerns of an oxygen leak in the ventilator housing, which poses a fire risk. We studied the ventilator at 1.0, 2.4 and 2.8 ATA in assist control mode using a Michigan test lung and a variety of tidal volumes and respiratory rates. We recorded the delivered volumes, peak pressures, and oxygen percentages within the hyperbaric chamber at 2.4 and 2.8 ATA and within the ventilator housing. At those pressures the ventilator delivered approximately 25% less volume than at 1.0 ATA. We observed breath stacking at high respiratory rates, but this was blunted at both 2.4 and 2.8 ATA. Oxygen levels did not rise in the housing during our investigation. In addition, we fit a linear regression to the data comparing set tidal volumes and delivered tidal volumes in order to model the changes observed. Hyperbaric conditions caused decreased delivered tidal volumes in a depth-dependent fashion, and oxygen levels within the housing did not rise. The Uni-Vent Eagle model 754 performed safely and effectively at depth but requires spirometry to correctly program desired ventilator settings.


Assuntos
Oxigenoterapia Hiperbárica , Ventiladores Mecânicos , Humanos , Oxigênio , Pressão , Volume de Ventilação Pulmonar
9.
Sci Rep ; 11(1): 22915, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824328

RESUMO

The gas sensor market is growing fast, driven by many socioeconomic and industrial factors. Mid-infrared (MIR) gas sensors offer excellent performance for an increasing number of sensing applications in healthcare, smart homes, and the automotive sector. Having access to low-cost, miniaturized, energy efficient light sources is of critical importance for the monolithic integration of MIR sensors. Here, we present an on-chip broadband thermal MIR source fabricated by combining a complementary metal oxide semiconductor (CMOS) micro-hotplate with a dielectric-encapsulated carbon nanotube (CNT) blackbody layer. The micro-hotplate was used during fabrication as a micro-reactor to facilitate high temperature (>700 [Formula: see text]C) growth of the CNT layer and also for post-growth thermal annealing. We demonstrate, for the first time, stable extended operation in air of devices with a dielectric-encapsulated CNT layer at heater temperatures above 600 [Formula: see text]C. The demonstrated devices exhibit almost unitary emissivity across the entire MIR spectrum, offering an ideal solution for low-cost, highly-integrated MIR spectroscopy for the Internet of Things.

10.
West J Emerg Med ; 22(5): 1028-1031, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34546876

RESUMO

INTRODUCTION: The novel coronavirus disease 2019 (COVID-19) created challenges with access to care including increased burden on healthcare systems and potential exposure risks for vulnerable patients. To address these needs, Rush University Medical Center created a virtual, urgent care program specifically designed to address these challenges during the COVID-19 pandemic. METHODS: This was a retrospective study analyzing adult patients with COVID-19-related telemedicine visits performed between March 1-June 30, 2020. COVID-19-related telemedicine visits refer to those who used the "Concern for Coronavirus" module. We assessed the total number of telemedicine visits using this module, percentage with a subsequent emergency department (ED) visit within seven days, and outcomes (ie, hospitalization status, intubation, and death) of patients who presented to the ED for evaluation. Data are presented using descriptive statistics. RESULTS: A total of 2,974 adult patients accessed the program via the COVID-19 module over the four-month period. Of those, 142 patients (4.8%) had an ED visit within seven days. Only 14 patients (0.5%) required admission. One patient was intubated, and there were no deaths among the telemedicine population. CONCLUSION: The data suggests that telemedicine may be a safe and effective way to screen and treat patients with possible COVID-19, while reducing potential burdens on EDs.


Assuntos
Assistência Ambulatorial/estatística & dados numéricos , COVID-19 , Programas de Rastreamento/métodos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2
11.
J Emerg Med ; 61(4): 420-423, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34332823

RESUMO

BACKGROUND: Coronavirus Disease 2019 (COVID-19) is a disease that presents with acute respiratory symptoms that are well documented and sequelae that are yet to be fully understood. CASE REPORT: We present the case of a 51-year old woman, recently diagnosed with COVID-19, who presented with symptoms including chest pain, palpitations, difficulty swallowing, and anterior neck discomfort. We ultimately diagnosed her with COVID-19-induced thyroiditis and discharged her on propranolol and nonsteroidal anti-inflammatory medication. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Thyroiditis can present with symptoms similar to other etiologies like pulmonary embolism. We discuss the process of evaluating and treating thyroiditis. We further discuss the risk of administering iodinated contrast media that could further exacerbate thyroid dysfunction.


Assuntos
COVID-19 , Tireoidite , Feminino , Humanos , Pessoa de Meia-Idade , SARS-CoV-2
13.
Diagnostics (Basel) ; 11(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401607

RESUMO

Neuromuscular electrical stimulation (NMES) is useful for muscle strengthening and for motor restoration of stroke patients. Using a portable ultrasound instrument, we developed an M-mode imaging protocol to visualize contractions elicited by NMES in the quadriceps muscle group. To quantify muscle activation, we performed digital image processing based on the Teager-Kaiser energy operator. The proposed method was applied for 35 voluntary patients (18 women and 17 men), of 63.8 ± 14.1 years and body mass index (BMI) 30.2 ± 6.70 kg/m2 (mean ± standard deviation). Biphasic, rectangular electric pulses of 350 µs duration were applied at two frequencies (60 Hz and 120 Hz), and ultrasound was used to assess the sensory threshold (ST) and motor threshold (MT) amplitude of the NMES signal. The MT was 23.4 ± 4.94 mA, whereas the MT to ST ratio was 2.69 ± 0.57. Linear regression analysis revealed that MT correlates poorly with body mass index (R2 = 0.004) or with the thickness of the subcutaneous adipose tissue layer that covers the treated muscle (R2 = 0.013). Our work suggests that ultrasound is suitable to visualize neuromuscular reactivity during electrotherapy. The proposed method can be used in the clinic, enabling the physiotherapist to establish personalized treatment parameters.

14.
Exp Ther Med ; 21(1): 89, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33363600

RESUMO

This prospective study explored the link between values of C-reactive protein (CRP) in patients with SpA (ankylosing spondylitis, psoriatic arthritis, reactive arthritis, or arthritis-related inflammatory bowel disease) and functional disability in order to derive an algorithm that may predict functional disability based on disease activity. Patients diagnosed with Spa were classified into five groups based on the type of therapy and they were followed up for 3 years. Group 1: Symptomatic medication alone; Group 2: Disease-modifying antirheumatic drugs (DMARDs); Group 3: DMARDs and 30 rehabilitation sessions twice a year; Group 4: Group 3 therapy and biologic anti-tumor necrosis factor-alpha (anti-TNF-α) drugs; and Group 5: Group 4 therapy and, in addition, a daily home-adapted kinesiotherapy program. CRP, modified Health Assessment Questionnaire (mHAQ-S), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and T-score of the patients were recorded. Correlation and multivariate regression analyses were conducted using demographic data, CRP, and mHAQ-S scores to derive the CRP-mHAQ-S correlation algorithm. Statistical analysis included the chi-square, Mann-Whitney, and multiple regression tests and repeated measures analysis of variance. A total of 144 patients were enrolled, all of whom completed the study. The best predictive model (P<0.001) provided the algorithm mHAQ-S36=17.14+0.12xCRP0-0.24xCRP12-0.15xCRP36 (CRP0, CRP12, and CRP36 correspond to CRP levels at baseline, 12, and 36 months, respectively, and mHAQ-S36 to mHAQ-S score at 36 months). This derived algorithm based on objective CRP assessment may have implications in the prediction of functional disability evolution in patients with SpA.

15.
Diving Hyperb Med ; 50(4): 391-398, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33325021

RESUMO

INTRODUCTION: Artisanal diving fishermen in Yucatán, Mexico have high rates of decompression sickness as a result of frequently unsafe diving practices with surface supplied compressed air. In this study, we investigated the prevalence of dysbaric osteonecrosis (DON), a type of avascular necrosis, in the most susceptible joints in a cohort of these fishermen. METHODS: We performed radiographs of bilateral shoulders, hips, and knees of 39 fishermen in Mexico and surveyed them about their medical and diving histories. We performed pairwise correlations to examine if the fishermen's diving behaviours affected the numbers of joints with DON. RESULTS: The radiographs revealed Grade II or higher DON in 30/39 (76.9%) of the fishermen. Twenty-two of 39 fishermen (56.4%) had at least two affected joints. The number of joints with DON positively correlates with the lifetime maximum diving depth and average bottom time. CONCLUSIONS: These findings represent among the highest prevalence rates of DON in divers and reflect the wide-spread scale of decompression sickness among these fishermen. Through this work, we hope to further educate the fishermen on the sequelae of their diving with the aim of improving their diving safety.


Assuntos
Doença da Descompressão , Mergulho , Doenças Profissionais , Osteonecrose , Doença da Descompressão/diagnóstico por imagem , Doença da Descompressão/epidemiologia , Doença da Descompressão/etiologia , Mergulho/efeitos adversos , Humanos , México/epidemiologia , Doenças Profissionais/diagnóstico por imagem , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Osteonecrose/diagnóstico por imagem , Osteonecrose/epidemiologia , Osteonecrose/etiologia
16.
Chirurgia (Bucur) ; 115(5): 665-669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33138904

RESUMO

Duplication of inferior vena cava (DIVC) is a rare congenital malformation of extreme importance for vascular and urology surgeons, interventional radiologists. Oftentimes it goes unnoticed and is diagnosed incidentally at a routine or emergency CT-scan when complications occur due to associated congenital malformations. We present a case of a 70-year-old male patient who was admitted into the emergency room (ER) accusing abdominal pain. He was diagnosed with an intestinal obstruction due to a left paraduodenal hernia (LPDH), associated with a DIVC. The reviewing the literature led to concluding that DIVC is not the cause of LPDH.


Assuntos
Hérnia Interna/etiologia , Obstrução Intestinal , Malformações Vasculares/complicações , Veia Cava Inferior/anormalidades , Dor Abdominal/etiologia , Idoso , Humanos , Obstrução Intestinal/etiologia , Masculino , Resultado do Tratamento
17.
J Emerg Med ; 59(6): e213-e216, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011039

RESUMO

BACKGROUND: Solomon Islands is a country in the South Pacific Ocean with excellent scuba diving, particularly among its remote islands that can be accessed by liveaboard dive boats. Blacktip reef sharks (Carcharhinus melanopterus) are found throughout the island nation and rarely attack humans. CASE REPORT: We present the case of a 42-year-old man who sustained a hand laceration after being bitten by a blacktip reef shark. He underwent complex primary wound closure in an austere environment and received prophylactic antibiotics. No infection developed and he recovered fully. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: We discuss our rationale in closing the wound aboard the dive boat, the choice of antibiotics, and review marine pathogens.


Assuntos
Mordeduras e Picadas , Mergulho , Tubarões , Adulto , Animais , Antibacterianos/uso terapêutico , Humanos , Masculino , Melanesia
18.
Sensors (Basel) ; 20(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32366021

RESUMO

We present a new experimental technique to characterise the crosstalk of a thermopile-based thermal imager, based on bi-directional electrical heating of thermopile elements. The new technique provides a significantly simpler and more reliable method to determine the crosstalk, compared to a more complex experimental setup with a laser source. The technique is used to characterise a novel single-chip array, fabricated on a single dielectric membrane. We propose a theoretical model to simulate the crosstalk, which shows good agreement with the experimental results. Our results allow a better understanding of the thermal effects in these devices, which are at the center of a rising market of industrial and consumer applications.

19.
J Emerg Med ; 57(5): 683-688, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31672399

RESUMO

BACKGROUND: Arterial gas embolus (AGE) is a rare complication of esophagoduodenoscopy (EGD) that has been described in only a few case reports in the literature. The exact etiology remains unknown, but many of the cases share some common characteristics. CASE REPORT: We report the case of a 52-year-old otherwise healthy man who underwent outpatient EGD for a sensation of retained food in his esophagus. During the procedure, he suffered a tonic-clonic seizure, bradycardia, and hypoxia. Subsequent emergency department workup showed pneumocephalus on computed tomography brain imaging, and he was diagnosed with a cerebral AGE (CAGE). He was transferred to our facility for treatment of CAGE with hyperbaric oxygen therapy (HBOT). After multiple hyperbaric treatments, he was discharged with a residual left hemiparesis, which represented a significant improvement in his overall neurologic status. We also present a review of similar EGD CAGE cases from the literature and discuss their outcomes and the need for HBOT. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although CAGE from EGD is rare, these patients will often be transferred to the ED from gastrointestinal procedural suites and an emergency physician should understand that an iatrogenic CAGE can result from this procedure and that CAGE is a clinical diagnosis. Definitive care at a critical care-capable hyperbaric chamber will provide the patient with the best chance of meaningful recovery, and transport should be arranged as expeditiously as possible.


Assuntos
Artérias/anormalidades , Embolia Aérea/etiologia , Endoscopia do Sistema Digestório/efeitos adversos , Artérias/diagnóstico por imagem , Embolia Aérea/epidemiologia , Serviço Hospitalar de Emergência/organização & administração , Endoscopia do Sistema Digestório/métodos , Humanos , Oxigenoterapia Hiperbárica/métodos , Doença Iatrogênica/epidemiologia , Masculino , Pessoa de Meia-Idade
20.
Phys Rev Lett ; 123(9): 093901, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31524444

RESUMO

Q switching (QS) and mode locking (ML) are the two main techniques enabling generation of ultrashort pulses. Here, we report the first observation of pulse evolution and dynamics in the QS-ML transition stage, where the ML soliton formation evolves from the QS pulses instead of relaxation oscillations (or quasi-continuous-wave oscillations) reported in previous studies. We discover a new way of soliton buildup in an ultrafast laser, passing through four stages: initial spontaneous noise, QS, beating dynamics, and ML. We reveal that multiple subnanosecond pulses coexist within the laser cavity during the QS, with one dominant pulse transforming into a soliton when reaching the ML stage. We propose a theoretical model to simulate the spectrotemporal beating dynamics (a critical process of QS-ML transition) and the Kelly sidebands of the as-formed solitons. Numerical results show that beating dynamics is induced by the interference between a dominant pulse and multiple subordinate pulses with varying temporal delays, in agreement with experimental observations. Our results allow a better understanding of soliton formation in ultrafast lasers, which have widespread applications in science and technology.

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