Increase in the density of β-FeSi2 nanoclusters on a Si(111) surface by means of Si(111) √3 × √3R30°-B reconstruction

The formation of iron disilicide (β-FeSi₂) nanoclusters as a result of solid-state epitaxy at T = 500–700°C and an iron coverage of 0.05–0.5 monolayer on a boron-modified Si(111)√3 × √3 R30° surface has been studied by scanning tunneling microscopy. It is established that the number density of β-FeSi₂ nanoclusters on the Si(111) √3 × √3 R30°-B surface significantly exceeds the density of silicide clusters formed on the atomically clean Si(111) surface with a 7 × 7 reconstruction for the analogous iron coverages and annealing temperatures. At the same time, the density of point defects and clusters possessing metallic conductivity on the Si(111) √3 × √3 R30°-B surface is several orders of magnitude lower than on the Si(111)7 × 7 surface treated under identical conditions.     

Extrapulmonary tuberculosis with multiple localizations in a patient with end‐stage renal disease

Bacteremia is a common complication for hemodialysis (HD) patients (pts) with an indwelling central venous catheter (CVC). We studied our experience with CAB and noted that CAB occurred at an average of 96 ± 98 days after CVC insertion. We wondered what percentage of CAB occurred in the first 21 days after CVC insertion and the spectrum of organisms. We prospectively collected data on all HD pts from 3 centers with a CVC who developed bacteremia between 1/1/03 and 8/31/04. Pts who developed CAB with an identifiable source of bacteremia were excluded. 131 episodes of CAB were identified; 34 (25.95%) occurred in ≤21 days. The mean ± SDEV age of the pts developing CAB > 21 days and ≤21 days was 63 ± 17 and 61.5 ± 15.4 years, respectively. Table 1 outlines the spectrum of organisms. There was a significantly greater incidence of CAB with Staphylococcus aureus (SA) and a significantly lower incidence of Staphylococcus epidermidis (SE) in the pts in whom a CAB developed ≤21 days after insertion.  

  Table 1     

3.

Carotid-jugular arteriovenous fistula and cerebrovascular infarct: a case report of an iatrogenic complication following internal jugular vein catheterization     

Bahcebasi S  Kocyigit I  Akyol L  Unal A  Sipahioğlu MH  Oymak O  Utas C 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(2):284-287

Central venous catheterization is frequently performed for perioperative management and long-term intravenous access. Although complications associated with central venous catheter insertion have been widely reported, there are few reports of carotid-jugular arteriovenous fistula formation. Endovascular procedures are associated with a risk of immediate and delayed thromboembolic and ischemic complications. We describe a case of a carotid-jugular arteriovenous fistula and a cerebrovascular infarct following the insertion of a double-lumen catheter for hemodialysis access. We provide recommendations for the prevention and the early detection of this iatrogenic complication.     

4.

The Dialysis Outcomes and Practice Patterns Study (DOPPS) in Turkey          下载免费PDF全文

Tevfik Ecder  Cengiz Utas  Kenan Ates  Brian Bieber  Bruce M. Robinson  Ronald L. Pisoni  Gültekin Süleymanlar 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(3):430-439

     

5.

In situConductance Measurement of Surface Phases on Silicon by the Four-Probe Method     

I. A. Belous  O. V. Utas  D. A. Tsukanov  V. G. Lifshits 《Instruments and Experimental Techniques》2001,44(5):698-699

The experimental chamber, automation system, and method for measuring the conductance of surface phases on silicon are described. This chamber is intended for measuring the conductance of superthin films and surface phases on single-crystal silicon substrates by the four-probe method under ultrahigh vacuum conditions (10^–10Torr). The system is controlled by a computer and contains 12-bit analog-to-digital and digital-to-analog converters. The measurement error is 0.5%. The measurement rate is 10 points/s.     

6.

Self-assembly of conductive Cu nanowires on Si(111)'5 × 5 '-Cu surface     

Tsukanov DA  Ryzhkova MV  Gruznev DV  Utas OA  Kotlyar VG  Zotov AV  Saranin AA 《Nanotechnology》2008,19(24):245608

Upon room-temperature deposition onto a Cu/Si(111)'5 × 5' surface in ultra-high vacuum, Cu?atoms migrate over extended distances to become trapped at the step edges, where they form Cu?nanowires (NWs). The formed NWs are 20-80?nm wide, 1-3?nm high and characterized by a resistivity of ～8?μΩ?cm. The surface conductance of the NW array is anisotropic, with the conductivity along the NWs being about three times greater than that in the perpendicular direction. Using a similar growth technique, not only the straight NWs but also other types of NW-based structures (e.g. nanorings) can be fabricated.     

7.

An overview of selected call processing patterns     

Utas  G. 《Communications Magazine, IEEE》1999,37(4):64-69

The call processing component of a switching system is responsible for setting up basic calls between external interfaces and for providing a broad range of supplementary services such as call forwarding, conference calling, and call waiting. This article discusses software design techniques that address some of the challenges faced when developing a call processing system. Each of these techniques is presented as a pattern, a term adopted by the software design community     

8.

Networked City Life in Africa: Introduction     

Ilda Lindell  Mats Utas 《Urban Forum》2012,23(4):409-414

     

9.

Modification of the sample holder for a variable temperature scanning tunneling microscope (Omicron)     

V. G. Kotlyar  B. K. Churusov  D. A. Olyanich  T. V. Utas  D. V. Gruznev  A. V. Zotov  A. A. Saranin 《Instruments and Experimental Techniques》2013,56(6):745-748

The design of a sample holder for a variable temperature scanning tunneling microscope (VT STM (Omicron)) with a variable sample temperature is described. This design considerably extends the range of investigated materials whose surface structure is sensitive to low concentrations of contaminations. The device is manufactured on the basis of the components of a standard holder with the possibility of heat-treating samples in a temperature range of 100–1500 K. The working capacity of the modified sample holder was demonstrated for an example of obtaining a Si(100)?2 × 1 surface with an ultimately low concentration of structural defects.     

10.

A cooling system for samples for studying their surfaces in ultrahigh vacuum     

B. K. Churusov  A. N. Kamenev  O. A. Utas  A. A. Saranin  A. V. Zotov  V. G. Kotlyar 《Instruments and Experimental Techniques》2006,49(1):141-143

The device described is designed to cool samples with liquid nitrogen to T=?165°C during low-energy electron diffraction (LEED) studies at an ultra-high-vacuum MALTIPROBE Compact system (Omicron) and versions thereof equipped with a scanning tunneling microscope and an LEED system. The efficiency of the system is demonstrated using the example of a low-temperature 2×1 ? c(4×2) phase transition on a (100)-oriented silicon surface observed using the LEED technique.     

1 [2] 下一页 » 末  页»

Carotid-jugular arteriovenous fistula and cerebrovascular infarct: a case report of an iatrogenic complication following internal jugular vein catheterization

Central venous catheterization is frequently performed for perioperative management and long-term intravenous access. Although complications associated with central venous catheter insertion have been widely reported, there are few reports of carotid-jugular arteriovenous fistula formation. Endovascular procedures are associated with a risk of immediate and delayed thromboembolic and ischemic complications. We describe a case of a carotid-jugular arteriovenous fistula and a cerebrovascular infarct following the insertion of a double-lumen catheter for hemodialysis access. We provide recommendations for the prevention and the early detection of this iatrogenic complication.     

In situConductance Measurement of Surface Phases on Silicon by the Four-Probe Method

The experimental chamber, automation system, and method for measuring the conductance of surface phases on silicon are described. This chamber is intended for measuring the conductance of superthin films and surface phases on single-crystal silicon substrates by the four-probe method under ultrahigh vacuum conditions (10^–10Torr). The system is controlled by a computer and contains 12-bit analog-to-digital and digital-to-analog converters. The measurement error is 0.5%. The measurement rate is 10 points/s.     

Self-assembly of conductive Cu nanowires on Si(111)'5 × 5 '-Cu surface

Upon room-temperature deposition onto a Cu/Si(111)'5 × 5' surface in ultra-high vacuum, Cu?atoms migrate over extended distances to become trapped at the step edges, where they form Cu?nanowires (NWs). The formed NWs are 20-80?nm wide, 1-3?nm high and characterized by a resistivity of ～8?μΩ?cm. The surface conductance of the NW array is anisotropic, with the conductivity along the NWs being about three times greater than that in the perpendicular direction. Using a similar growth technique, not only the straight NWs but also other types of NW-based structures (e.g. nanorings) can be fabricated.     

An overview of selected call processing patterns

The call processing component of a switching system is responsible for setting up basic calls between external interfaces and for providing a broad range of supplementary services such as call forwarding, conference calling, and call waiting. This article discusses software design techniques that address some of the challenges faced when developing a call processing system. Each of these techniques is presented as a pattern, a term adopted by the software design community     

Modification of the sample holder for a variable temperature scanning tunneling microscope (Omicron)

The design of a sample holder for a variable temperature scanning tunneling microscope (VT STM (Omicron)) with a variable sample temperature is described. This design considerably extends the range of investigated materials whose surface structure is sensitive to low concentrations of contaminations. The device is manufactured on the basis of the components of a standard holder with the possibility of heat-treating samples in a temperature range of 100–1500 K. The working capacity of the modified sample holder was demonstrated for an example of obtaining a Si(100)?2 × 1 surface with an ultimately low concentration of structural defects.     

A cooling system for samples for studying their surfaces in ultrahigh vacuum

The device described is designed to cool samples with liquid nitrogen to T=?165°C during low-energy electron diffraction (LEED) studies at an ultra-high-vacuum MALTIPROBE Compact system (Omicron) and versions thereof equipped with a scanning tunneling microscope and an LEED system. The efficiency of the system is demonstrated using the example of a low-temperature 2×1 ? c(4×2) phase transition on a (100)-oriented silicon surface observed using the LEED technique.