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1.
Sensors (Basel) ; 23(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37420883

RESUMO

The integration of the physical and digital world has become increasingly important, and location-based services have become the most sought-after application in the field of the Internet of Things (IoT). This paper delves into the current research on ultra-wideband (UWB) indoor positioning systems (IPS). It begins by examining the most common wireless communication-based technologies for IPSs followed by a detailed explanation of UWB. Then, it presents an overview of the unique characteristics of UWB technology and the challenges still faced by the IPS implementation. Finally, the paper evaluates the advantages and limitations of using machine learning algorithms for UWB IPS.


Assuntos
Internet das Coisas , Tecnologia sem Fio , Comunicação
3.
Sensors (Basel) ; 23(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37896691

RESUMO

Indoor localization is a key research area and has been stated as a major goal for Sixth Generation (6G) communications. Indoor localization faces many challenges, such as harsh wireless propagation channels, cluttered and dynamic environments, non-line-of-sight conditions, etc. There are various technologies that can be applied to address these issues. In this paper, four major technologies for implementing an indoor localization system are reviewed: Wireless Fidelity (Wi-Fi), Ultra-Wide Bandwidth Radio (UWB), Bluetooth Low Energy (BLE), and Inertial Measurement Units (IMU). Sections on Data Fusion (DF) and Machine Learning (ML) have been included as well due to their key role in Indoor Positioning Systems (IPS). These technologies have been categorized based on the techniques that they employ and the associated errors in localization. A brief comparison between these technologies is made based on specific performance metrics. Finally, the limitations of these techniques are identified to aid future research.

4.
Sensors (Basel) ; 22(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408051

RESUMO

The existing sub-6 GHz band is insufficient to support the bandwidth requirement of emerging data-rate-hungry applications and Internet of Things devices, requiring ultrareliable low latency communication (URLLC), thus making the migration to millimeter-wave (mmWave) bands inevitable. A notable disadvantage of a mmWave band is the significant losses suffered at higher frequencies that may not be overcome by novel optimization algorithms at the transmitter and receiver and thus result in a performance degradation. To address this, Intelligent Reflecting Surface (IRS) is a new technology capable of transforming the wireless channel from a highly probabilistic to a highly deterministic channel and as a result, overcome the significant losses experienced in the mmWave band. This paper aims to survey the design and applications of an IRS, a 2-dimensional (2D) passive metasurface with the ability to control the wireless propagation channel and thus achieve better spectral efficiency (SE) and energy efficiency (EE) to aid the fifth and beyond generation to deliver the required data rate to support current and emerging technologies. It is imperative that the future wireless technology evolves toward an intelligent software paradigm, and the IRS is expected to be a key enabler in achieving this task. This work provides a detailed survey of the IRS technology, limitations in the current research, and the related research opportunities and possible solutions.

5.
Molecules ; 27(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35268623

RESUMO

Headspace solid microextraction (HS-SPME) and GC-MS were used to investigate volatile organic compounds (VOCs) from cabbage plants infested and uninfested with green peach aphid Myzus persicae. The HS-SPME combined with GC-MS analysis of the volatiles described the differences between the infested and uninfested cabbage. Overall, 28 compounds were detected in infested and uninfested cabbage. Some VOCs released from infested cabbage were greater than uninfested plants and increased the quantity of the composition from infested plants. According to the peak area from the GC-MS analysis, the VOCs from infested cabbage consisted of propane, 2-methoxy, alpha- and beta pinene, myrcene, 1-hexanone, 5-methyl-1-phenyl-, limonene, decane, gamma-terpinen and heptane, 2,4,4-trimethyl. All these volatiles were higher in the infested cabbage compared with their peak area in the uninfested cabbage. The results of the study using a Y-shape olfactometer revealed that the VOCs produced by infested cabbage attracted Myzus persicae substantially more than uninfested plants or clean air. The percentage of aphid choice was 80% in favor of infested cabbage; 7% were attracted to the clean air choice and uninfested plants. A total of aphids 7% were attracted to clean air. Comparing between infested and uninfested cabbage plants, the aphid was attracted to 63% of the infested cabbage, versus 57% of the uninfested cabbage. The preferences of Aphidus colemani and Aphelinus abdominalis to the infested or uninfested plants with M. persicae and compared with clean air indicated that parasitoids could discriminate the infested cabbage. Both parasitoids significantly responded to the plant odor and were attracted to 86.6% of the infested cabbage plants.


Assuntos
Afídeos , Brassica , Himenópteros , Compostos Orgânicos Voláteis , Animais , Afídeos/fisiologia , Odorantes , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/farmacologia
6.
Eur Arch Otorhinolaryngol ; 278(7): 2461-2471, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32897441

RESUMO

PURPOSE: Consistent prognosticators are needed to guide adjuvant treatment in tongue squamous cell carcinoma (SCC). We validate the prognostic significance of histopathologic parameters in surgically treated tongue SCC. METHODS: Archival specimens of 88 consecutive patients who were treated surgically for tongue SCC from 2003 to 2016 were re-analyzed by one pathologist. Patient records were retrospectively reviewed. Prognosticators of recurrence-free survival (RFS), overall survival (OS), and disease-specific survival (DSS) were identified using multivariate analysis. RESULTS: Tumor depth of invasion (DOI) > 6 mm (OR 4.76; 95%CI 1.22-18.5; p = 0.024) and lymphovascular invasion (OR 5.61; 95%CI 1.00-31.5; p = 0.05) were independent predictors of nodal metastases. The overall 5-year RFS, OS and DSS were 70%, 82% and 84% respectively. Positive margins predicted poor RFS (HR 3.91; 95%CI 1.58-9.65; p = 0.003) and local recurrence-free survival (HR 4.96; 95%CI 1.36-18; p = 0.015). Presence of nodal metastases (HR 5.03; 95%CI 1.73-14.6; p = 0.003), tumor DOI > 6 mm (HR 9.91; 95%CI 1.26-78.0; p = 0.029) and positive margins (HR 8.26; 95%CI 2.75-24.8; p < 0.001) were independent predictors of poor OS. Presence of nodal metastases (HR 3.87; 95%CI 1.17-12.8; p = 0.027) and positive margins (HR 12.3; 95%CI 3.54-42.9; p < 0.001) also independently predicted poor DSS. CONCLUSION: Margins' status was the only independent predictor of local recurrence. Tumor DOI, nodal and margin status were key prognosticators of survival and may determine the necessity for adjuvant therapy.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Humanos , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Língua/patologia , Neoplasias da Língua/patologia , Neoplasias da Língua/cirurgia
7.
Sensors (Basel) ; 21(3)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494191

RESUMO

The Department of Transport in the United Kingdom recorded 25,080 motor vehicle fatalities in 2019. This situation stresses the need for an intelligent transport system (ITS) that improves road safety and security by avoiding human errors with the use of autonomous vehicles (AVs). Therefore, this survey discusses the current development of two main components of an ITS: (1) gathering of AVs surrounding data using sensors; and (2) enabling vehicular communication technologies. First, the paper discusses various sensors and their role in AVs. Then, various communication technologies for AVs to facilitate vehicle to everything (V2X) communication are discussed. Based on the transmission range, these technologies are grouped into three main categories: long-range, medium-range and short-range. The short-range group presents the development of Bluetooth, ZigBee and ultra-wide band communication for AVs. The medium-range examines the properties of dedicated short-range communications (DSRC). Finally, the long-range group presents the cellular-vehicle to everything (C-V2X) and 5G-new radio (5G-NR). An important characteristic which differentiates each category and its suitable application is latency. This research presents a comprehensive study of AV technologies and identifies the main advantages, disadvantages, and challenges.

8.
Sensors (Basel) ; 21(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066695

RESUMO

In this paper, an analytical framework is presented for device detection in an impulse radio (IR) ultra-wide bandwidth (UWB) system and its performance analysis is carried out. The Neyman-Pearson (NP) criteria is employed for this device-free detection. Different from the frequency-based approaches, the proposed detection method utilizes time domain concepts. The characteristic function (CF) is utilized to measure the moments of the presence and absence of the device. Furthermore, this method is easily extendable to existing device-free and device-based techniques. This method can also be applied to different pulse-based UWB systems which use different modulation schemes compared to IR-UWB. In addition, the proposed method does not require training to measure or calibrate the system operating parameters. From the simulation results, it is observed that an optimal threshold can be chosen to improve the ROC for UWB system. It is shown that the probability of false alarm, PFA, has an inverse relationship with the detection threshold and frame length. Particularly, to maintain PFA<10-5 for a frame length of 300 ns, it is required that the threshold should be greater than 2.2. It is also shown that for a fix PFA, the probability of detection PD increases with an increase in interference-to-noise ratio (INR). Furthermore, PD approaches 1 for INR >-2 dB even for a very low PFA i.e., PFA=1×10-7. It is also shown that a 2 times increase in the interference energy results in a 3 dB improvement in INR for a fixed PFA=0.1 and PD=0.5. Finally, the derived performance expressions are corroborated through simulation.

9.
Molecules ; 26(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065463

RESUMO

The insecticidal activities of essential oils obtained from black pepper, eucalyptus, rosemary, and tea tree and their binary combinations were investigated against the green peach aphid, Myzus persicae (Aphididae: Hemiptera), under laboratory and glasshouse conditions. All the tested essential oils significantly reduced and controlled the green peach aphid population and caused higher mortality. In this study, black pepper and tea tree pure essential oils were found to be an effective insecticide, with 80% mortality when used through contact application. However, for combinations of essential oils from black pepper + tea tree (BT) and rosemary + tea tree (RT) tested as contact treatment, the mortality was 98.33%. The essential oil combinations exhibited synergistic and additive interactions for insecticidal activities. The combination of black pepper + tea tree, eucalyptus + tea tree (ET), and tea tree + rosemary showed enhanced activity, with synergy rates of 3.24, 2.65, and 2.74, respectively. Essential oils formulation was effective on the mortality of aphids. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that stability of a mixture of essential oils was not affected by store temperature (15, 25, and 35 °C) and the functional groups were not changed during storage. Based on our results, the essential oils can be used as a commercial insecticide against M. persicae.


Assuntos
Afídeos/efeitos dos fármacos , Inseticidas/farmacologia , Óleos Voláteis/farmacologia , Animais , Sinergismo Farmacológico , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Eur Spine J ; 25(12): 3997-4007, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26188770

RESUMO

PURPOSE: To evaluate the feasibility of using intraoperative cell salvage (IOCS) in combination with leucocyte depletion filter (LDF) in eliminating tumour cells from blood salvaged during metastatic spine tumour surgery (MSTS). This is with the view to pave the path for use of IOCS-LDF in MSTS and musculoskeletal oncological surgery. METHODS: Sixty consecutive patients with known primary epithelial tumour, who were offered surgery for metastatic spine disease at our university hospital, were recruited. Blood samples were collected at three different stages during surgery: from operative field prior to IOCS processing, after IOCS processing and after IOCS-LDF processing. Three separate samples (5 ml each) were taken at each stage. Samples were examined by cell block technique using immunohistochemical monoclonal antibodies to identify tumour cells of epithelial origin in the samples. RESULTS: Of 60 patients, ten were excluded for not fulfilling the inclusion criteria leaving 50 patients. Malignant tumour cells were detected in the samples from operative field prior to IOCS processing in 24 patients and in the samples from the transfusion bag post-IOCS processing in 4 patients. No viable malignant cells were detectable in any of the blood samples after passage through both IOCS and LDF. CONCLUSIONS: The findings support the notion that IOCS-LDF combination works effectively in eliminating tumour cells from salvaged blood so this technique can possibly be applied in MSTS and even musculoskeletal oncological surgery. This concept can then be extended to other oncological surgeries in general with further appropriate clinical studies.


Assuntos
Recuperação de Sangue Operatório/métodos , Neoplasias da Coluna Vertebral/cirurgia , Separação Celular , Estudos de Viabilidade , Filtração , Humanos , Metástase Neoplásica , Células Neoplásicas Circulantes
11.
Lancet Oncol ; 15(1): e33-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24384492

RESUMO

Metastatic spine tumour surgery (MSTS) and metastatic musculoskeletal tumour surgery (MMTS) are associated with substantial blood loss. Allogeneic blood transfusion is the present method used to replenish this blood. Intraoperative cell salvage (IOCS) is a viable alternative, but is contraindicated in tumour surgery because of the risk of tumour dissemination. Use of IOCS-leucocyte depletion filter (LDF) allows removal of tumour cells from blood salvaged during oncological surgery. However, no reports exist on use of IOCS in MSTS or MMTS. We systematically reviewed studies on IOCS in oncological surgery to investigate whether sufficient evidence exists to support its use in MSTS or MMTS.


Assuntos
Transfusão de Sangue Autóloga/métodos , Procedimentos de Redução de Leucócitos , Neoplasias da Coluna Vertebral/cirurgia , Neoplasias Ósseas/cirurgia , Neoplasias Gastrointestinais/cirurgia , Humanos , Período Intraoperatório , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/secundário , Metástase Neoplásica , Neoplasias da Coluna Vertebral/patologia , Neoplasias Urológicas/cirurgia
12.
Ann Surg Oncol ; 21(7): 2436-43, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24566859

RESUMO

BACKGROUND: Intraoperative cell salvage (IOCS) has been used in musculoskeletal surgery extensively. However, it has never found its place in musculoskeletal oncologic surgery. We have conducted the first-ever study to evaluate the feasibility of IOCS in combination with a leucocyte-depletion filter (LDF) in metastatic spine tumor surgery. This was to pave the path for use of IOCS-LDF in musculoskeletal oncologic surgery. METHODS: Patients with a known primary epithelial tumor, who were offered surgery for metastatic spinal disease, were recruited. Blood samples were collected at three different stages during the surgery: from the operative field before IOCS processing, after IOCS processing, and after IOCS-LDF processing. Three separate samples (5 mL each) were taken at each stage. Samples were examined using immunohistochemical monoclonal antibodies to identify tumor cells of epithelial origin. RESULTS: Of 30 patients in the study, 6 were excluded for not fulfilling the inclusion criteria, leaving 24 patients. Malignant tumor cells were detected in the samples from the operative field before IOCS processing in eight patients and in the samples from the transfusion bag after IOCS processing in three patients. No viable malignant cell was detectable in any of the blood samples after passage through both IOCS and LDF. CONCLUSIONS: The findings support the notion that the IOCS-LDF combination works effectively in eliminating tumor cells from salvaged blood, so this technique can be applied successfully in spine tumor surgery. This concept can then further be extended to whole musculoskeletal tumor surgery and other oncologic surgeries with further appropriate clinical studies.


Assuntos
Cuidados Intraoperatórios , Neoplasias Epiteliais e Glandulares/cirurgia , Recuperação de Sangue Operatório/métodos , Neoplasias da Coluna Vertebral/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Procedimentos de Redução de Leucócitos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/patologia , Prognóstico , Estudos Prospectivos , Neoplasias da Coluna Vertebral/secundário
13.
Eur Endod J ; 9(2): 146 - 153, 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38219029

RESUMO

OBJECTIVE: To compare the effectiveness of lateral canal irrigation penetration by conventional needle, passive ultrasonic, sonic endo activator, and Erbium laser (2780nm). METHODS: A total of 40 palatal roots of human maxillary first molars were collected and instrumented at a working length of 12 mm by an X1-X4 rotary Protaper Next system (Dentsply, Maillefer, Ballaigues, Switzerland) using the crown-down technique. Artificial lateral canals were made at 2, 4, and 6 mm from the apex on mesial and distal sides using an ISO rotary reamer (Dentsply, Maillefer, Ballaigues, Switzerland; #10 for mesial, #08 for distal). The samples were then cleared using methyl salicylate. A solution of black ink and normal saline was used as an irrigant for the root canal. The percentages of the penetration of the ink into the lateral canals were measured using a stereomicroscope (Q-Scope, Arnhem, The Netherlands) with the aid of program Image J. The Tukey test is used to assess the significant difference between intragroup and intergroup comparisons of different thirds, and the T-test is used to assess the significant difference between every two groups and for the mesial and distal sides of each group. The level of significance was set at 0.05. RESULTS: Results showed that none of the activation techniques used resulted in complete lateral canal penetrations; however, on both sides at all thirds, the Erbium laser (2780 nm) achieved the highest results with a highly significant statistical difference (p=0.05) with all other groups, and the least penetration was in the conventional needle group. CONCLUSION: The size of the lateral canal is a restricting factor for all activation methods; the best results can be achieved by laser. Conventional needles cannot be used alone to disinfect complex canal anatomy; however, passive ultrasonic and sonic endo activator activations can produce comparable results.


Assuntos
Cavidade Pulpar , Érbio , Polimetil Metacrilato , Humanos , Érbio/farmacologia , Preparo de Canal Radicular/métodos , Ultrassom
14.
Clin Case Rep ; 12(5): e8823, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38681031

RESUMO

Early identification of rib fractures, even in young patients without chronic diseases, is essential. Prompt diagnosis facilitates appropriate management, aiding in pain control and addressing underlying causes such as persistent coughing. Additionally, vigilance for complications such as pneumothorax and rib displacement is crucial for optimizing patient care.

15.
Clin Case Rep ; 12(2): e8511, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38333658

RESUMO

De Winter syndrome, though rare, demands heightened clinical suspicion. Recognizing its electrocardiographic subtleties is crucial, as prompt diagnosis allows for life-saving interventions such as percutaneous coronary intervention or thrombolysis.

16.
Oxf Med Case Reports ; 2024(6): omae056, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38860016

RESUMO

We present the case of a 27-year-old pregnant woman, newly diagnosed with Systemic Lupus Erythematosus (SLE) during pregnancy. The patient delivered a newborn at 38 weeks gestation, who, on the first day of life, manifested complete heart block. This case underscores the clinical challenges associated with neonatal lupus, emphasizing the need for collaborative, multidisciplinary management.

17.
SAGE Open Med Case Rep ; 12: 2050313X241258738, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812830

RESUMO

This case report outlines the management of a 43-year-old male with no past medical history presenting with inferior ST-segment elevation myocardial infarction and a positive "Dead Man Sign." Prompt administration of antiplatelet therapy and emergent percutaneous coronary intervention led to successful revascularization of the occluded right coronary artery and left anterior descending artery. The patient remained asymptomatic throughout hospitalization and was discharged home with instructions for monthly follow-up for 1 year. Subsequent assessments demonstrated normal echocardiography and Electrocardiography (ECG) findings, indicating favorable cardiac recovery. This case emphasizes the critical importance of rapid recognition and intervention in ST-segment elevation myocardial infarction cases, as well as the significance of the Dead Man Sign as a predictor of the occluded culprit coronary vessels, demonstrating favorable outcomes achievable with timely revascularization strategies.

18.
Clin Case Rep ; 12(4): e8574, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623360

RESUMO

Key Clinical Message: Ibuprofen single dose may rarely induce Stevens-Johnson Syndrome, emphasizing the vital need for heightened vigilance in healthcare and public awareness for safer medication practices. Abstract: Stevens-Johnson Syndrome (SJS) is a severe and potentially life-threatening skin disorder associated with certain medications, including ibuprofen. We present a case of a 45-year-old woman who developed SJS following a single dose of ibuprofen. Despite its rarity, this case underscores the importance of heightened vigilance in healthcare and public awareness regarding the potential risks of commonly used medications. Prompt recognition of SJS symptoms and immediate medical intervention are crucial for patient outcomes. Healthcare providers should exercise caution when prescribing ibuprofen, particularly in patients with a history of adverse drug reactions. This case emphasizes the need for ongoing monitoring, patient education, and informed decision-making to promote medication safety and optimal patient care.

19.
Clin Case Rep ; 12(6): e9051, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38836110

RESUMO

Key Clinical Message: Timely recognition of atypical Takayasu arteritis is crucial. Unusual presentations, such as pericardial effusion, can complicate diagnosis. CT angiogram aids in precise diagnosis, guiding targeted immunosuppressive therapy. Multidisciplinary collaboration is vital for comprehensive management, improving patient outcomes in this challenging condition. Abstract: This case study highlights the diagnostic challenges posed by atypical presentations of Takayasu arteritis (TA), focusing on a 42-year-old male presenting with pericardial effusion. Despite inconclusive initial investigations, a CT angiogram revealed large vessel vasculitis, confirming TA. Management with immunosuppressive therapy led to clinical improvement. This case emphasize the importance of recognizing unusual manifestations of TA for timely diagnosis and appropriate treatment, emphasizing the role of multidisciplinary collaboration in optimizing patient outcomes.

20.
Clin Case Rep ; 12(2): e8502, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38344352

RESUMO

Key Clinical Message: This case underscores the atypical presentation of late-onset congenital diaphragmatic hernia in a 9-old with 1p36 deletion syndrome. Recognition of respiratory distress and abdominal symptoms is crucial for intervention. Abstract: Congenital Diaphragmatic Hernia (CDH) is a condition characterized by the protrusion of abdominal contents into the thoracic cavity due to a defect in the diaphragm. While typically observed in the neonatal period, CDH can present in later life. This case report describes the presentation, diagnosis, and management of a nine-year-old boy with 1p36 deletion syndrome who presented with respiratory distress, abdominal pain, vomiting, and anorexia. The initial diagnosis was tension pneumothorax, and thus the patient underwent chest tube placement. However, a high-resolution CT scan revealed a left hemidiaphragmatic hernia, and the patient eventually underwent an emergency laparotomy due to acute-onset respiratory distress. Intraoperatively, a diagnosis of Bochdalek hernia with gastric perforation was made, and the CDH and gastric perforations were resolved successfully. This case highlights the importance of considering late-presenting CDH as a possible diagnosis in pediatric patients with similar symptoms and the radiological findings suggestive of tension pneumothorax. Early recognition and prompt surgical intervention can lead to successful management of such cases.

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