Sepsisli Hastalarda Transfüzyonu Belirlemede Şok İndekslerinin Rolü

Amaç: Şok indeksleri özellikle hemorajik şok durumunda transfüzyonu ön görmede kullanılmaktadır. Ancak sepsis hastalarında transfüzyonu belirlemek için şok indekslerinin kullanımı konusunda yeterli çalışma yoktur. Çalışmamızda Yoğun bakım ünitesine (YBÜ) yatan sepsis ve septik şoktaki hastalarda şok indeksi (SI), modifiye şok indeksi (MSI) ve yaş şok indeksinin (YSI) hastaların eritrosit transfüzyonunu ön görmede kullanılabilirliğinin araştırılması amaçlanmıştır. Gereç ve Yöntem: Çalışmamız Anesteziyoloji ve Yoğun Bakım Ünitesi Kliniğinde 1 Kasım 2017 ile 31 Aralık 2018 tarihleri arasında retrospektif hasta verileri değerlendirilerek yapıldı. Hastaların yaşları, cinsiyetleri, eşlik eden hastalıkları, akut fizyoloji ve kronik sağlık değerlendirme (APACHE II) skoru, mekanik ventilasyon süresi, yatış süresi, hemoglobulin değerleri, SI, MSI, YSI, eritrosit transfüzyon verileri kayıt edildi. Bulgular: Çalışmaya 225 hasta dahil edildi. Şok indeksi, MSI, YSI düzeyleri eritrosit transfüzyonu gerektiren hastalarda gerektirmeyen hastalara göre istatistiksel olarak anlamlı yüksekti (p<0,05). Şok indeksi için ROC (receiver operating characteristic) eğrisi altındaki alan 0,691'dir (% 95 güven aralığı (GA): 0,626 - 0,751 P = 0,0002). Transfüzyon için SI eşik değeri 0,98’dir (duyarlılık: %86,8, %95 GA: 71,9-95,5, özgüllük: %46,52, %95 GA: 39,2-53,9). MSI için ROC eğrisi altındaki alan 0,666’dır (% 95 GA: 0,601-0,728 P = 0,0012). Transfüzyon için MSI eşik değeri 1,67’dir (duyarlılık: %57,9 %95 GA: 40,8-73,7, özgüllük: %72,7, %95 GA: 65,7-79). Yaş SI için ROC eğrisi altındaki alan 0,639’'dur (% 95 GA: 0,572-0,702 P = 0,0076). Transfüzyon için YSI eşik değeri 102,85’tir (duyarlılık: %39,5, %95 GA: 21,4-56,6, özgüllük: %89,8, %95 GA: 84,6-93,8). Sonuç: Sepsis hastalarında şok indeksleri transfüzyon ihtiyacını belirlenmede kullanılabilir. Ancak şok indeksleri ile beraber ek parametrelerin kullanılması gerekmektedir

Electronics for embedded systems

This book provides semester-length coverage of electronics for embedded systems, covering most common analog and digital circuit-related issues encountered while designing embedded system hardware. It is written for students and young professionals who have basic circuit theory background and want to learn more about passive circuits, diode and bipolar transistor circuits, the state-of-the-art CMOS logic family and its interface with older logic families such as TTL, sensors and sensor physics, operational amplifier circuits to condition sensor signals, data converters and various circuits used in electro-mechanical device control in embedded systems. The book also provides numerous hardware design examples by integrating the topics learned in earlier chapters. The last chapter extensively reviews the combinational and sequential logic design principles to be able to design the digital part of embedded system hardware

Fundamentals of computer architecture and design

This textbook provides semester-length coverage of computer architecture and design, providing a strong foundation for students to understand modern computer system architecture and to apply these insights and principles to future computer designs.  It is based on the author’s decades of industrial experience with computer architecture and design, as well as with teaching students focused on pursuing careers in computer engineering.  Unlike a number of existing textbooks for this course, this one focuses not only on CPU architecture, but also covers in great detail in system buses, peripherals and memories.This book teaches every element in a computing system in two steps.  First, it introduces the functionality of each topic (and subtopics) and then goes into “from-scratch design” of a particular digital block from its architectural specifications using timing diagrams.  The author describes how the data-path of a certain digital block is generated using timin g diagrams, a method which most textbooks do not cover, but is valuable in actual practice.  In the end, the user is ready to use both the design methodology and the basic computing building blocks presented in the book to be able to produce industrial-strength designs.   • Provides semester-length textbook for students in computer and electrical engineering, covering the design of complex computing blocks from archite ctural specifications; • Focuses not only on CPU architecture, but also covers in detail system buses, peripherals and memories; • Presented in a manner catering to young engineering minds, this textbook minimizes text, while using a systematic design approach with architectural schematics, timing diagrams and control circuits; • Includes extensive exercises and projects at the end of each chapter; • Solutions to review problems and PowerPoint slides for instructors available.  

Electronics for Embedded Systems

This book is written for young professionals, undergraduate and graduate students who have a background in basic circuit theory and want to learn about the circuits used in printed circuit boards and embedded systems. My teaching method in this textbook caters towards a lot of schematics, block diagrams and examples at the expense of text because I believe in engineers are “shape-oriented” people and learn from ?gures, charts and diagrams. The book has nine chapters. Chapter 1 analyzes the ?rst-order passive RC and RL circuits and the second-order passive RLC circuits encountered in all Printed Circuit Boards (PCB). The general understanding of passive circuits also establishes a vital background for more complex circuits that contain active elements such as diodes and transistors

Structural characterization of fluidized bed nitrided steels

The nitriding behaviour of 34CrAlNi7, 42CrMo4 and 40CrMnMoS86 steels was investigated nitrided in the fluidized bed processes. The nitriding processes were carried out at a temperature of 575 degrees C for treatment times of 6, 12 and 18 h. The nitrided samples were fully characterized using metallographic, microhardness and XRD techniques. Test results indicated that thickness of the compound layer on the steel surface changed in the range from 10 to 18 mu m depending on steel type and treatment time, and gamma'-Fe4N and epsilon-Fe2-3N formed in the compound layer. The hardness of the diffusion layer was over 1000 HV. Depending on the chemical composition of steels, the case depth ranged from 155 to 525 mu m. Kinetics studies showed that the effective diffusion coefficients are 298 x 10(-14) 525 x 10(-14) and 68.8 x 10(-14) m(2)s(-1), for 34CrAlNi7, 42CrMo4 and 40CrMnMoS86 steels, respectively. The fluidized bed process realizes the highest hardness of the case layer, 1095 HV, with fairly high growth rates, 27 mu m/h. (c) 2005 Elsevier Ltd. All rights reserved

Characterization of Plasma Nitrided X32CrMoV33 Die Steel

In this study, nitriding behavior of plasma nitrided X32CrMoV33 die steel was investigated. Nitriding process was carried out at temperatures of 450, 500, and 550 degrees C for treatment time in the range of 2-32h. Depending on nitriding temperature and time, the thickness of compound layer ranged from 2 mu m to 15 mu m. The presence of '-Fe4N, epsilon-Fe2-3N, -Fe, and Cr2N phases formed in the compound layer was confirmed by XRD analysis. Using cross-sectional samples and a microhardness indenter, hardness depth profiles were also obtained; it was found that the hardness of compound layer was over 1000HV. Kinetic studies revealed that the effective diffusion coefficients for plasma nitrided X32CrMoV33 are approximately 40.3x10-14, 99.2x10-14, and 427x10-14m2s-1 for 450, 500, and 550 degrees C process temperatures, respectively. The activation energy for plasma nitrided X32CrMoV33 steel is 118.77kJ mol-1

Silicon nanowire transistors

This book describes the n and p-channel Silicon Nanowire Transistor (SNT) designs with single and dual-work functions, emphasizing low static and dynamic power consumption. The authors describe a process flow for fabrication and generate SPICE models for building various digital and analog circuits. These include an SRAM, a baseband spread spectrum transmitter, a neuron cell and a Field Programmable Gate Array (FPGA) platform in the digital domain, as well as high bandwidth single-stage and operational amplifiers, RF communication circuits in the analog domain, in order to show this technology’s true potential for the next generation VLSI. Describes Silicon Nanowire (SNW) Transistors, as vertically constructed MOS n and p-channel transistors, with low static and dynamic power consumption and small layout footprint; Targets System-on-Chip (SoC) design, supporting very high transistor count (ULSI), minimal power consumption requiring inexpensive substrates for packaging; Enables fabrication of different types of memory on the same chip, such as capacitive cells and transistors with floating gates that can be used as DRAMs and Flash memories

Design and Characterization of the Next Generation Nanowire Amplifiers

Vertical nanowire surrounding gate field effect transistors (SGFETs) provide full gate control over the channel to eliminate short-channel effects. This paper presents design and characterization of a differential pair amplifier using NMOS and PMOS SGFETs with a 10 nm channel length and a 2 nm channel radius. The amplifier dissipates 5 μW power and provides 5 THz bandwidth with a voltage gain of 16, a linear output voltage swing of 0.5 V, and a distortion better than 3% from a 1.8 V power supply and a 20 aF capacitive load. The 2nd- and 3rd-order harmonic distortions of the amplifier are −40 dBm and −52 dBm, respectively, and the 3rd-order intermodulation is −24 dBm for a two-tone input signal with 10 mV amplitude and 10 GHz frequency spacing. All these parameters indicate that vertical nanowire surrounding gate transistors are promising candidates for the next generation high-speed analog and VLSI technologies

C-Reaktif Protein/Prealbumin Oranı Yoğun Bakım Hastalarının 48 Saatlik Mortalitesini Tahmin Edebilir mi? Retrospektif Kohort

Amaç: Yoğun bakımdan taburculuk sırasında devam eden inflamasyonun mortalite üzerindeki önemi yeterince tanımlanmamıştır. C-reaktif protein (CRP) ve albümin seviyeleri, inflamasyonu göstermek için iyi belirteçlerdir. Yüksek inflamasyon ve inflamasyonla birlikte görülen yetersiz beslenme, mortaliteyi daha da artırır. Prealbumin düzeyleri de çeşitli hasta gruplarında mortalite tahmini için kullanılmıştır. Çalışmamızda hastaların prealbumin, CRP ve albümin düzeylerinin yoğun bakım mortalitesini 48 saat önce tahmin etmesini öngörmeyi amaçladık. Yöntemler: Hastaların demografik özellikleri, APACHE (Acute Physiology and Chronic Health Evaluation) II skorları, CRP, albümin ve prealbumin değerleri yoğun bakıma kabul ve yoğun bakım ünitesinden taburculuktan 48 saat önce değerlendirildi. Bulgular: Hastaların 103’ü kadın ve 124’ü erkekti. 128 hasta kaybedildi ve 99 hasta taburcu edildi. Gruplar arasında APACHE II skorları arasında istatistiksel olarak anlamlı fark yoktu. Prealbumin (7.8 mg / dL) (P ? 0.0001) ve albümin (2.1 g / dL) (P ? 0.0001) düzeyleri, sağkalım grubuna göre kaybedilenler grubunda anlamlı olarak düşüktü. Kaybedilen hasta grubunda CRP (P ? 0.0001), CRP / Albumin (P ? 0.0001) ve CRP / Prealbumin (P ? 0.0001) düzeyleri anlamlı olarak yüksekti. CRP / Prealbumin düzeylerinin mortalitenin öngörülmesinde yüksek duyarlı (% 82.8) ve yüksek özgül (% 89.9) olduğu bulunmuştur. Sonuç: CRP / Prealbumin düzeyi yoğun bakım ünitesinde 48 saat öncesinde mortaliteyi öngörmede etkili bir parametredir