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1.
Leuk Res ; 140: 107484, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38520796

RESUMO

INTRODUCTION: Thrombocytopenia is among the most common complications following hematopoietic stem cell transplantation and is associated with increased mortality and morbidity with no standard treatment yet. In this multicenter and retrospective study, we aim to present our multi-center experience of Eltrombopag treatment in patients with isolated thrombocytopenia following HSCT. MATERIAL-METHOD: A total of 73 patients from 5 centers who underwent autologous or allogeneic stem cell transplantation, had no primary disease relapse, all of whom had neutrophil engraftment, complete chimerism, and who were diagnosed with Prolonged Isolated Thrombocytopenia (PIT) or Secondary Failure Of Platelet Recovery (SFPR) were included in the study. The patients were initiated on Eltrombopag at a dose of 50-150 mg. Complete response was defined as a platelet count >50×109/L for 7 consecutive days with no transfusion support. RESULTS: A total of 50.3% of the patients underwent Autologous and 49.7% Allogeneic Stem Cell Transplantation, 54.8% were diagnosed with PIT, and 45.2% were diagnosed with SFPR, and the treatment with 50-150 mg/day Eltrombopag was initiated on the median day +42. Complete response was achieved in 71.2% of these patients on the median day 23 of the treatment. No significant effects of the initial dose (50-150 mg/day) were detected in the Complete Response in the multivariate analysis on response. An insufficient number of Megakaryocytes in the bone marrow before Eltrombopag treatment was determined as an independent risk factor in determining the response (OR 3.57, 95% CI 1.21-10.55). The overall survival of the patients who did not respond to Eltrombopag was found to be significantly worse than that of patients who responded (p=0.022, HR:2.74, 95% CI 1.12-6.54). CONCLUSION: As a result of the present study, Eltrombopag treatment was found to be effective and safe in thrombocytopenia that develops following hematopoietic stem cell transplantation. It was concluded that its use may be more effective in patients with sufficient bone marrow megakaryocytes before the treatment and an initial dose of 50 mg/day may be appropriate in terms of cost, effectiveness, and toxicity. Large-scale randomized and controlled prospective studies are needed to determine the roles of Eltrombopag treatment in patients with post-transplant PIT and SFPR.


Assuntos
Benzoatos , Transplante de Células-Tronco Hematopoéticas , Hidrazinas , Pirazóis , Trombocitopenia , Humanos , Hidrazinas/uso terapêutico , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Benzoatos/uso terapêutico , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Pirazóis/uso terapêutico , Pirazóis/efeitos adversos , Pirazóis/administração & dosagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Feminino , Masculino , Trombocitopenia/etiologia , Trombocitopenia/tratamento farmacológico , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem , Adolescente , Idoso , Contagem de Plaquetas
2.
Front Psychol ; 14: 1191631, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38115979

RESUMO

Introduction: Advances in technology make it easier for users to post content on social media. People can post different types of content in digital environments. Sometimes, they post such content in risky situations. Accordingly, this study aims to determine the sociological and psychological reasons why people record dangerous occurrences where they or other people are under risk or threat and post these recordings on social media. Methods: This study aimed to answer five research questions. a) Why do individuals use social media? b) Why do people post on social media? c) What types of posts do people share on social media? d) What are the possible psychological reasons that push people to share such occurrences on social media? e) Why do individuals feel the need to record and share dangerous occurrences while under risk or danger? This study was conducted on the basis of a case study design, and interviews were conducted with two psychiatrists, two specialist clinical psychologists, and two sociologists. Results: After the interviews, the reasons why individuals use social media platforms and post on the said platforms were laid out. It can be argued that the most prominent reason behind individuals' tendency to post while under risk or threat is isolation and inability to help.

4.
Work ; 74(3): 1035-1054, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36442179

RESUMO

BACKGROUND: Work stress and feeling of entrapment are harmful physical and emotional results for employees when the workload demands exceed their capacities. OBJECTIVE: This study aims to investigate the effects of the career management system and succession plan on employees' work stress and feelings of entrapment in hopes of improving employees' well-being to promote business continuity. METHODS: In this cross-sectional study, the convenient sampling method was adopted. The research was conducted with the participation of call center agents (n = 621) of three call centers in Turkey. The Partial Least Squares Structural Equation Modeling (PLS-SEM) path analysis was performed on the collected data for hypothesis testing. RESULTS: Both career management systems (CMS) and succession plans (SP) reduce employees' work stress and feelings of entrapment. Work stress was found to mediate the effects of CMS and SP on the Feeling of Entrapment. The CMS reduces the work stress of employees with university degrees than those with a high school diploma. Meanwhile, SP reduces more of the feeling of entrapment for employees newly starting their jobs (with 0-2 years of seniority) than the workers with three or more years of seniority. CONCLUSION: Empirically, the feeling of entrapment seems higher among the employees with three or more years of seniority, suggesting that human resource management should focus on employees' work stress and feeling of job insecurity issues and offer possible and timely solutions. Furthermore, organizations showing care to newly arriving staff and giving them job assurance is believed crucial to improving employees' recruitment and retention.


Assuntos
Estresse Ocupacional , Humanos , Estudos Transversais , Estresse Ocupacional/psicologia , Emoções , Instituições Acadêmicas , Inquéritos e Questionários
5.
Artigo em Inglês | MEDLINE | ID: mdl-35976543

RESUMO

Internet use among children is increasing. This requires parents to develop digital parenting competencies as they are responsible for their children's well-being. In the current study the digital parenting self-efficacy perceptions of Turkish parents are examined with regard to the parental role, educational status, age, number of children, and Internet use experiences. Data were collected from a stratified sample of 7150 Turkish parents (i.e., only the mother or father in each family) from twenty-six provinces through the Digital Parenting Self-Efficacy Perception Scale. Descriptive statistics, comparison tests, and cluster analysis were used to analyze the data. The findings reveal that the participants' perceived digital parenting efficacy is high, and that perceptions change in terms of the parental role, educational status, age, number of children, and the Internet use experience.

6.
Opt Express ; 29(11): 17628-17668, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154302

RESUMO

Guided acoustic Brillouin (GAWBS) noise is measured using a novel, homodyne measurement technique for four commonly used fibers in long-distance optical transmission systems. The measurements are made with single spans and then shown to be consistent with separate multi-span long-distance measurements. The inverse dependence of the GAWBS noise on the fiber effective area is confirmed by comparing different fibers with the effective area varying between 80 µm2 and 150 µm2. The line broadening effect of the coating is observed, and the correlation between the width of the GAWBS peaks to the acoustic mode profile is confirmed. An extensive model of the GAWBS noise in long-distance fibers is presented, including corrections to some commonly repeated mistakes in previous reports. It is established through the model and verified with the measurements that the depolarized scattering caused by TR2m modes contributes twice as much to the optical noise in the orthogonal polarization to the original source, as it does to the noise in parallel polarization. Using this relationship, the polarized and depolarized contributions to the measured GAWBS noise is separated for the first time. As a result, a direct comparison between the theory and the measured GAWBS noise spectrum is shown for the first time with excellent agreement. It is confirmed that the total GAWBS noise can be calculated from fiber parameters under certain assumptions. It is predicted that the level of depolarized GAWBS noise created by the fiber may depend on the polarization diffusion length, and consequently, possible ways to reduce GAWBS noise are proposed. Using the developed theory, dependence of GAWBS noise on the location of the core is calculated to show that multi-core fibers would have a similar level of GAWBS noise no matter where their cores are positioned.

7.
J Matern Fetal Neonatal Med ; 34(17): 2863-2868, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31630583

RESUMO

PURPOSE: Preeclampsia is a form of hypertensive disorders of pregnancy and defined as the presence of new-onset hypertension and proteinuria or other end organ damage occurring after 20-week gestation. Preeclampsia can be a destructive process that can cause maternal and infant mortality. The exact etiopathogenesis of preeclampsia is still undefined. We aimed to compare serum amphiregulin and cerebellin-1 levels of severe preeclampsia patients with healthy pregnant women and healthy control subjects. MATERIALS AND METHODS: A total of 88 women were enrolled in this study. Patients diagnosed with severe preeclampsia were group 1 (n = 28), healthy non-pregnant normotensive women group 2 (n = 30), and healthy pregnant women group 3 (n = 30). The participants in each group were matched for age. Pregnant women in groups 1 and 3 were also matched for gestational age. Serum amphiregulin and cerebellin-1 levels were measured using ELISA. RESULTS: Serum amphiregulin levels were 3413 ± 1.38 ng/ml (1748-7739), 8510 ± 7213 ng/ml (2019-24,000), and 6580 ± 5360 ng/ml (2484-24,000) in preeclampsia patients, controls and healthy pregnant women, respectively. Amphiregulin levels were significantly lower in preeclampsia patients than healthy pregnant women (p=.008) and controls (p = .015). Amphiregulin levels were similar between healthy controls and healthy pregnant women (p = 1.00). Cerebellin-1 levels were 222.039 ± 92.681 pg/ml (138,580-557,757) in preeclamptic patients, 537.043 ± 525.117 pg/ml (150,432-1,600,000) in controls and 415.091 ± 436.580 pg/ml (137,284-1,600,000) in healthy pregnant women. Cerebellin-1 levels were similar among groups (p = .272). Serum amphiregulin and cerebellin-1 levels were significantly and positively correlated with each other in preeclampsia patients (r = 0.693, p < .001), controls (r = 0.882, p < .001), and healthy pregnant women (r = 0.591, p = .001). Serum level of amphiregulin ≤3590 pg/ml had a sensitivity of 67.9% and specificity of 63.3% in the diagnosis of preeclampsia (AUC: 0.751; p = .001). CONCLUSIONS: Serum amphiregulin decreases in severe preeclampsia patients.


Assuntos
Pré-Eclâmpsia , Anfirregulina , Pressão Sanguínea , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Proteínas do Tecido Nervoso , Gravidez , Precursores de Proteínas
8.
Nat Commun ; 10(1): 3033, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292442

RESUMO

Fiber nonlinearity is one of the major limitations to the achievable capacity in long distance fiber optic transmission systems. Nonlinear impairments are determined by the signal pattern and the transmission system parameters. Deterministic algorithms based on approximating the nonlinear Schrodinger equation through digital back propagation, or a single step approach based on perturbation methods have been demonstrated, however, their implementation demands excessive signal processing resources, and accurate knowledge of the transmission system. A completely different approach uses machine learning algorithms to learn from the received data itself to figure out the nonlinear impairment. In this work, a single-step, system agnostic nonlinearity compensation algorithm based on a neural network is proposed to pre-distort symbols at transmitter side to demonstrate ~0.6 dB Q improvement after 2800 km standard single-mode fiber transmission using 32 Gbaud signal. Without prior knowledge of the transmission system, the neural network tensor weights are constructed from training data thanks to the intra-channel cross-phase modulation and intra-channel four-wave mixing triplets used as input features.

9.
Opt Express ; 21(12): 14244-50, 2013 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-23787613

RESUMO

We demonstrated the first 30Tb/s (350 × 85.74Gb/s) optical transmission over 10,181km using bidirectional C/L-bands, 121.2km hybrid fiber spans, DP-QPSK modulation and EDFAs. Achieved 306Petabit/s•km capacity × distance product is the highest reported to date for WDM transmission.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Tecnologia de Fibra Óptica/instrumentação , Telecomunicações/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
10.
Opt Express ; 20(3): 2668-80, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22330504

RESUMO

We demonstrate mode-division multiplexed WDM transmission over 50-km of few-mode fiber using the fiber's LP01 and two degenerate LP11 modes. A few-mode EDFA is used to boost the power of the output signal before a few-mode coherent receiver. A 6×6 time-domain MIMO equalizer is used to recover the transmitted data. We also experimentally characterize the 50-km few-mode fiber and the few-mode EDFA.


Assuntos
Amplificadores Eletrônicos , Fibras Ópticas , Processamento de Sinais Assistido por Computador/instrumentação , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
11.
Opt Express ; 19(20): 19042-9, 2011 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-21996844

RESUMO

The performance of rate-0.8 4-ary LDPC code has been studied in a 50 GHz-spaced 40 Gb/s DWDM system with PDM-QPSK modulation. The net effective coding gain of 10 dB is obtained at BER of 10(-6). With the aid of time-interleaving polarization multiplexing and MAP detection, 10,560 km transmission over legacy dispersion managed fiber is achieved without any countable errors. The proposed nonbinary quasi-cyclic LDPC code achieves an uncoded BER threshold at 4×10(-2). Potential issues like phase ambiguity and coding length are also discussed when implementing LDPC in current coherent optical systems.


Assuntos
Tecnologia de Fibra Óptica/métodos , Micro-Ondas , Dispositivos Ópticos , Fibras Ópticas , Processamento de Sinais Assistido por Computador , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento
12.
Opt Express ; 18(20): 21342-9, 2010 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-20941030

RESUMO

Few-mode fibers (FMFs) are used for the first time to transmit over 5000 km. Ten WDM channels with 50GHz channel spacing at 112 Gb/s per channel using PDM-QPSK are launched into the fundamental mode of the FMFs by splicing single-mode fibers directly to the FMFs. Even though few-mode fibers can support an additional spatial mode LP(11) at 1550 nm, the signal remains in the fundamental mode and does not experience mode coupling throughout fiber transmission. After each span the signal is collected by a second single-mode fiber which is also spliced to the FMF. Span loss is compensated by single-mode EDFAs before it is launched to the next FMF span. The lack of mode coupling ensures that the signal does not suffer any impairments that may result from differential mode delay or excess loss. Therefore the FMFs used in this "single-mode operation" have the same bandwidth as single-mode fibers. Experimental results verified that FMFs have the significant advantage of large core size which reduces the nonlinear impairments suffered by the signal. It is shown that FMFs with an effective area of 130 µm(2), have an optimum launch power 2 dB higher compared to standard single-mode fibers and as a result a 1.1 dB improvement in the Q-factor is obtained after 3000 km.

13.
Opt Express ; 18(14): 15144-54, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20639999

RESUMO

An advanced split-step method is employed for the digital backward-propagation (DBP) method using the coupled nonlinear Schrodinger equations for the compensation of inter-channel nonlinearities. Compared to the conventional DBP, cross-phase modulation (XPM) can be efficiently compensated by including the effect of the inter-channel walk-off in the nonlinear step of the split-step method (SSM). While self-phase modulation (SPM) compensation is inefficient in WDM systems, XPM compensation is able to increase the transmission reach by a factor of 2.5 for 16-QAM-modulated signals. The advanced SSM significantly relaxes the step size requirements resulting in a factor of 4 reduction in computational load.

14.
Opt Express ; 18(12): 13250-7, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20588454

RESUMO

Using multimode fibers for long-haul transmission is proposed and demonstrated experimentally. In particular few-mode fibers (FMFs) are demonstrated as a good compromise since they are sufficiently resistant to mode coupling compared to standard multimode fibers but they still can have large core diameters compared to single-mode fibers. As a result these fibers can have significantly less nonlinearity and at the same time they can have the same performance as single-mode fibers in terms of dispersion and loss. In the absence of mode coupling it is possible to use these fibers in the single-mode operation where all the data is carried in only one of the spatial modes throughout the fiber. It is shown experimentally that the single-mode operation is achieved simply by splicing single-mode fibers to both ends of a 35-km-long dual-mode fiber at 1310 nm. After 35 km of transmission, no modal dispersion or excess loss was observed. Finally the same fiber is placed in a recirculating loop and 3 WDM channels each carrying 6 Gb/s BPSK data were transmitted through 1050 km of the few-mode fiber without modal dispersion.

15.
Opt Express ; 16(2): 880-8, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18542162

RESUMO

A universal post-compensation scheme for fiber impairments in wavelength-division multiplexing (WDM) systems is proposed based on coherent detection and digital signal processing (DSP). Transmission of 10 x 10 Gbit/s binary-phase-shift-keying (BPSK) signals at a channel spacing of 20 GHz over 800 km dispersion shifted fiber (DSF) has been demonstrated numerically.


Assuntos
Comunicação , Tecnologia de Fibra Óptica/instrumentação , Micro-Ondas , Modelos Teóricos , Processamento de Sinais Assistido por Computador/instrumentação , Tomografia de Coerência Óptica/métodos , Artefatos , Simulação por Computador , Sistemas Computacionais , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
16.
Opt Lett ; 33(5): 488-90, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18311301

RESUMO

All-optical control of the phase-matching condition in four-wave mixing (FWM) processes is demonstrated using the Brillouin slow-light effect in optical fibers. A counterpropagating stimulated Brillouin scattering (SBS) pump has been used to control the phase velocity of the FWM pump in a wavelength conversion scheme. Both experimental results and theoretical simulations show an SBS-controlled 20 dB difference on the wavelength conversion efficiency.

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