End Side Research Articles

Solidity effect on corner separation and its control in a high-speed low aspect ratio compressor cascade

Three-dimensional (3D) corner separation flow is the main source of losses and blockages in compressors, and it is vital to the compressor performance. This paper investigates the solidity effect on the evolution of 3D corner separation in a high-speed low aspect ratio cascade. The effect of solidity on the corner separation mechanism is analysed in detail and the relative position relationship between the separation point and the blade suction surface throat position, is found to be critical to the evolution of the 3D corner separation. A new type of separation termed blade suction surface stall, is proposed, on occasion of negative S indicator values. The formation mechanism for this newly proposed stall is investigated in detail, in association with the solidity variation. This kind of stall occurs when the onset of the separation point moves ahead of the throat point on the blade suction surface and simultaneously with the confluence of the two end side separation zones in the blade middle. Based on the detachment mechanisms for the evolution of the 3D corner separation, a blade end jet control scheme is conceived to mitigate the 3D corner separation. The results indicate its benefit range and verify the potential of implementing it incorporated with solidity reduction.

Sensory nerve baby-sitting in reverse end-to-side fashion improves the recovery of denervated muscle in rats

Objective To delay the atrophy of denervated skeletal muscle by baby-sitting in reverse end-to-side fashion and explore the feasibility of this operation to improve the recovery of denervated muscle in rats. Methods From July, 2015 to March, 2016, 32 female SD rats were divided into 4 groups randomly and the tibial nerve of each rats was transected. In immediate repair group, the transected tibial nerve was sutured in situ. In unprotected group, the tibial nerve stump was putting-aside. The sural nerve was transected in other 2 groups. The proximal sural nerve was connected to the distal tibial nerve stump directly in end-to-end (ETE) protected group and to the side of the distal tibial nerve stump in end-to-side (ETS) protected group. After 3 months, connected the two ends of tibial nerve except immediate repair group. After another 3 months, the tibial nerve functional index, electrophysiological testing, histology and morphology were examined. Results The gastrocnemius muscle was atrophy obviously in unprotected group, while in other groups the muscle structure was well protected. The tibial nerve functional index (-39.54±24.32) , motor nerve conduction velocity[ (30.25±12.65) m/s], and muscle contraction [ (0.98 ± 0.38) N) ] indicated that the gastrocnemius muscle function in ETS protected group was statistically better recovery than in unprotected group [-75.65±32.13, (24.93±8.69) m/s and (0.64±0.20) N, respectively] and ETE protected group[-62.34±21.65, (16.90±7.92) m/s and (0.75±0.15) N, respectively] (P 0.05) . Conclusion Sensory nerve baby-sitting in reverse end-to-side fashion is a effective method to improve the recovery of denervated muscle in rats. Key words: Muscular atrophy; Denervated muscle; Nerve baby-sitting; End-to-side suture; Rat

Dynamic Quantitative Assessment of Motor Axon Sprouting after Direct Facial–Hypoglossal End-To-Side Neurorrhaphy in Rats

End-to-side (ETS) neurorrhaphy is a promising procedure for peripheral nerve repair, yet controversies regarding the efficacy of this repair in facial nerve anastomosis for facial paralysis still exist. Thirty rats were divided into three groups: intact control group, direct facial-hypoglossal ETS neurorrhaphy, and end-to-end (ETE) neurorrhaphy. Nerve regeneration was assessed with vibrissae motor performance, electrophysiological tests, retrograde labeling, and histomorphological analysis at 4 and 8 months postoperatively. Both ETS and ETE neurorrhaphies resulted in axonal regeneration and functional recovery of the recipient nerve but did not reach the level of intact controls. Significantly higher numbers of myelinated axons and labeled neurons giving regenerating fibers were found in group ETE compared with group ETS at both time points, consistent with the functional and electrophysiological recovery. Group ETS showed significantly smaller fiber diameter and thinner myelin thickness than group ETE at 4 months, but the difference became nonsignificant at 8 months. ETS neurorrhaphy had a very slight effect on the donor nerve, as determined electrophysiologically and histomorphologically. Sparsely distributed double-labeled neurons and relatively large amounts of single-labeled neurons contributing to reinnervation were found through double retrograde neuronal labeling in group ETS. Further quantitative analysis of the percentage of double-labeled neurons showed a pronounced tendency to decline from 19.8% at 4 months to 6.0% at 8 months postoperatively. Successful reinnervation after ETS neurorrhaphy could be achieved through both collateral sprouting and terminal sprouting, with the latter seeming to be the principal origin of motor nerve sprouting.

An Efficient ROI Image Watermarking on Geometric Attacks

Watermarking is raised to apparatus for the Privacy of Intellectual Property Rights (IPR) of combination dates. In this paper, in the starting we have to fill the user name field and password field which will be secure afterwards that it will be make QR-code using zxing library and it is transformed into binary patterns for share-1 that is called Visual cryptography algorithm. Now share-2 is store into server database and it will be furthered use in future situation at receiver way. Now share-1 is hiding into the LL-Band with the help of DWT-SVD into block manner with Pseudo Zernike moment. Then it is sent to the network or internet. As in network there are many unlike attackers whose apply any Rotation, Scaling or Translation attacks on the hiding image. Attack image is expected at the end side or receiver side. To get prevent against attacks here at the starting stage use Pseudo Zernike moment then after Surf based feature extraction and it will recover the attacks pixel and scaling parameters value and using affine transformation recover the rotational parameters value. So then scale value and angle value is apply on attack image recovered watermark image. Now using DWT+SVD block method extract the water mark share-1. So on system with share-1 and another share-2 will be in server side so now by using EX-OR process for getting QR-Code. At the last stage QR-code is translated and fill field user name and password vale to login the system successfully.

The honey insertion cladding to improve the sensitivity of temperature polymer optical fiber sensor

The sensitivity of temperature polymer optical fiber (POF) sensor has been studied. Part of cladding (9 cm) was substituted with honey. Polymer cladding was stripped mechanically and the honey inserted into the tube. Plastic gel closed the two end sides of the tubes. The optical power output was detected by Optical Power Meter (OPM). Honey cladding and temperature changing effect to the internal reflection and optical fiber output intensity. Highest output intensity changing at 20°C was shown by optical fiber coated by longan honey as cladding. The range of 10-50° C, as the rise of surroundings temperature, the attenuation was getting smaller. Best sensitivity was fiber with sensing part coated by Longan honey. Best linearity was sensing fiber with sensing part coated by Pracimantoro honey.

Identification of Wiskott-Aldrich syndrome protein (WASP) binding sites on the branched actin filament nucleator Arp2/3 complex

Arp2/3 complex nucleates branched actin filaments important for cellular motility and endocytosis. WASP family proteins are Arp2/3 complex activators that play multiple roles in branching nucleation, but little is known about the structural bases of these WASP functions, owing to an incomplete understanding of how WASP binds Arp2/3 complex. Recent data show WASP binds two sites, and biochemical and structural studies led to models in which the WASP C segment engages the barbed ends of the Arp3 and Arp2 subunits while the WASP A segment binds the back side of the complex on Arp3. However, electron microscopy reconstructions showed density for WASP inconsistent with these models on the opposite (front) side of Arp2/3 complex. Here we use chemical cross-linking and mass spectrometry (XL-MS) along with computational docking and structure-based mutational analysis to map the two WASP binding sites on the complex. Our data corroborate the barbed end and back side binding models and show one WASP binding site on Arp3, on the back side of the complex, and a second site on the bottom of the complex, spanning Arp2 and ARPC1. The XL-MS-identified cross-links rule out the front side binding model and show that the A segment of WASP binds along the bottom side of the ARPC1 subunit, instead of at the Arp2/ARPC1 interface, as suggested by FRET experiments. The identified binding sites support the Arp3 tail release model to explain WASP-mediated activating conformational changes in Arp2/3 complex and provide insight into the roles of WASP in branching nucleation.

Two new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) from Trachinus spp. (Osteichthyes: Trachinidae) in the Gulf of Hammamet, Tunisia.

Based on light and scanning electron microscopical studies, two new gonad-infecting species of Philometra Costa, 1845, P. draco n. sp. and P. radiata n. sp. (Nematoda: Philometridae), are described from the marine perciform fishes Trachinus draco (Linnaeus) and T. radiatus (Linnaeus) (both Trachinidae), respectively, in the Gulf of Hammamet, off the northeastern coast of Tunisia. Philometra draco n. sp. and P. radiata n. sp. can be separated from other gonad-infecting species of this genus by the structures associated to the gubernaculum (e.g. dorsal protuberance, smooth field separating the dorsolateral longitudinal parts), as well as by the length of the body, spicules and gubernaculum. Philometra radiata n. sp. can be distinguished from P. draco n. sp. in having the dorsal side of the gubernaculum distal end provided with a median longitudinal smooth field demarcated by two dorsolateral lamellate parts. These two new species are the first philometrid species described from fishes of the family Trachinidae.

The third osseous ambiguous tubercle-A study on Indian population

Abstract Background & Aim: Bony prominences on the medial side of the lower end of femur include the adductor tubercle and the medial epicondyle. A third osseous ambiguous tubercle or the Gastrocnemius tubercle is often noted about which there is not much mention in standard textbooks of Anatomy. This tubercle gives attachment to the medial head of gastrocnemius muscle. Its clinical relevance cannot be under estimated particularly in cases of treatment of rupture of medial head of gastrocnemius [Tennis leg] and while raising of Gastrocnemius flaps. Materials and Methods: This study was conducted in150 dry femora and in 10 dissected knee joints [Total femora 160 : 150 dry bones+ 10 cadaveric femora] gross specimens. The presence of gastrocnemius tubercle, supracondylar tubercle, the distances between gastrocnemius tubercle and adductor tubercle, medial epicondyle and condylar margin were measured. Results: The incidence of gastrocnemius tubercle was 55% and was predominantly noted on the right side [63%]. The average distance between the gastrocnemius tubercle and the adductor tubercle was 6 mm, and the average distance between the gastrocnemius tubercle and medial epicondyle was 15 mm. The incidence ofsupracondylartubercle was 71% and in 95% of the bones it was noted above the medial condylar margin. Conclusion: The awareness of the presence of gastrocnemius tubercle and supracondylar bony prominences in the medial side of lower end of femur will be of much use to the Orthopaedic surgeons and Plastic surgeons

Geometric Three-Dimensional End-to-Side Microvascular Anastomosis: A Simple and Reproducible Technique.

End-to-side (ETS) anastomoses are useful when preservation of distal vascularity is critical. The ideal ETS microanastomosis should maintain a wide aperture and have a smooth take-off point to minimize turbulence, vessel spasm, and thrombogenicity of the suture line. We have developed a unique, dependable, and reproducible geometric technique for ETS anastomoses, and analyze its efficacy in our series of patients. The geometric ETS technique involves creating a three-dimensional (3D) diamond-shaped defect on the recipient vessel wall, followed by a slit incision of the donor vessel to create a "spatula" fitting this defect. This technique removes sutures from the point of most turbulent blood flow while holding the recipient vessel open with a patch vesselplasty effect. We perform a retrospective review of a single surgeon's experience using this technique. The geometric 3D ETS technique was used in 87 free flaps with a total of 102 ETS anastomoses in a wide range of cases including head and neck, trunk and genitourinary, and extremity reconstruction. Overall, free flap success rates were 98%. The geometric 3D ETS technique creates a wide anastomosis, minimizes turbulence-inducing thrombogenicity, and mechanically holds the recipient vessel open. It is reliable and reproducible, and when performed properly has been shown to have high rates of success in a large group of free tissue transfer patients.

Analysis of Computational Fluid Dynamics and Particle Image Velocimetry Models of Distal-End Side-to-Side and End-to-Side Anastomoses for Coronary Artery Bypass Grafting in a Pulsatile Flow.

Intimal hyperplasia (IH) is a major cause of graft failure. Hemodynamic factors such as stagnation and disturbed blood flow are involved in IH formation. The aim of this study is to perform a comparative analysis of distal-end side-to-side (deSTS) and end-to-side (ETS) anastomoses using computational fluid dynamics (CFD) after validating the results via particle image velocimetry (PIV).Methods and Results:We investigated the characteristics of our target flow fields using CFD under steady and pulsatile flows. CFD via PIV under steady flow in a 10-times-actual-size model was validated. The CFD analysis revealed a recirculation zone in the heel region in the deSTS and ETS anastomoses and at the distal end of the graft, and just distal to the toe of the host artery in the deSTS anastomoses. The recirculation zone sizes changed with the phase shift. We found regions of low wall shear stress and high oscillating shear index in the same areas. The PIV and CFD results were similar. It was demonstrated that the hemodynamic characteristics of CFD and PIV is the difference between the deSTS and ETS anastomoses; that is, the deSTS flow peripheral to the distal end of the graft, at the distal end and just distal to the toe of the host artery is involved in the IH formation.

Does Anastomosis Configuration Influence Long-term Outcomes in Patients With Crohn Disease?

PurposeIn this study, we evaluated the role of various anastomoses in surgical recurrence for patients with Crohn disease (CD).MethodsWe analyzed data retrospectively from consecutive laparotomy cases involving complicated CD between 1991 and 2008. Clinical data were compared in terms of reoperation-free survival (RFS) according to the types of anastomoses, the materials used for the anastomoses, and the operating surgeon.ResultsOf 233 patients with entero-enteric or entero-colic anastomoses, 199 (85%), 11 (5%), and 23 (10%) experienced side-to-side (SS), side-to-end (SE), and end-to-end (EE) anastomoses, respectively. The SS group had the following characteristics: more extensive bowel involvement, frequent obstruction, and greater stapler use; the SS anastomoses were also frequently made by specialized surgeons (P < 0.001–0.004). EE anastomoses were frequently made by general surgeons using a hand-sewing technique (P < 0.001). No differences in RFS were noted among the 3 groups according to the type of anastomosis and the operating surgeon. However, the hand-sewn group showed better RFS than the stapler group (P = 0.04).ConclusionThe roles of the anastomotic configuration, the material used, and the operating surgeon were not significantly correlated with reoperations or complications in our retrospective CD cohort, irrespective of the higher risk of anastomosis site stricture for EE anastomoses.

Effect of FK1706 on nerve regeneration after end-to-side neurorrhaphy of autonomic nerve and somatic nerve in rats

Objective To evaluate the effect of FK1706 on nerve regeneration after end-to-side (ETS) neurorrhaphy of autonomic nerve and somatic nerve in rats through morphological observation. Methods Thirty rats were randomly divided into three groups in terms of different treatments (n=10 in each group). In FK1706 group, the left L6 ventral root (L6VR) and L4 ventral root (L4VR) of rats were sutured in an ETS fashion and FK1706 (0.3 mg/kg) was administrated subcutaneously for 5 consecutive days per week for a total of 8 weeks after ETS neurorrhaphy. In ETS group, the same operation as FK1706 group was performed but without FK1706 applied after surgery. In control group, left L6 dorsal root (L6DR), S1 ventral root (S1VR) and S1 dorsal root (S1DR) were transected but the left L6VR was preserved as normal control. After 4 months, the left pelvic parasympathetic nerve (PPN) to which L6VR extended was harvested for semithin and ultrathin sections in FK1706 and ETS groups to count the number of myelinated axons. The number and morphology of myelinated axons and thickness of myelin sheath were compared between the two groups. Results After 4 months, the morphology of the regenerated L6VR distal to the neurorrhaphy site in FK1706 and ETS groups was normal. The number of regenerated myelinated axons of PPN was 515.6±43.3 and 328.4±46.4 in FK1706 and ETS groups, respectively (P=0.000). The thickness of myelin sheath of regenerated PPN was (0.672 4±0.110 1) μm and (0.466 8±0.076 3) μm in FK1706 and ETS groups, respectively (P=0.000). Conclusion The effect of autonomic nerve regeneration could be enhanced after ETS neurorrhaphy of autonomic nerve and somatic nerve through FK1706, which could improve rehabilitation of nerve injury. Key words: FK1706; Nerve regeneration; Autonomic nerve; Somatic nerve; End-to-side neurorrhaphy

Bougies as an aid for endotracheal intubation with the Airway Scope: bench and manikin comparison studies

BackgroundWhen encountering a difficult airway with an Airway Scope (AWS) a bougie can be inserted into the endotracheal tube in the AWS channel. The angulated tip of the bougie can be guided toward the glottis by rotating it. We tested the ease of rotating bougies (Venn reusable, Boussignac, Portex single-use, and Frova) in an endotracheal tube when placed in the AWS channel.MethodsBench study: Seven anesthesiologists inserted each of the four types of bougies into a 7.0 mm endotracheal tube in an AWS channel and rotated the bougie end (side of bougie operated by hand) clockwise or counterclockwise to an angle of 0°-180° in 45° increments. The rotation angle of the bougie tip (tracheal side) was measured for each bougie and the degree of force required to rotate them was examined. Manikin study: Using the same four bougies, the same seven anesthesiologists attempted to intubate a manikin that simulated a difficult airway. Success rate and time required for successful intubation were compared between the four bougies.ResultsBench study: The difference in the rotation angle between the bougie tip and end was significantly larger with Portex single-use and Frova bougies than with Venn reusable and Boussignac bougies (P < 0.01). The rotation angles of the tips of Venn reusable, Boussignac, Portex single-use, and Frova bougies were 145°/123° (clockwise / counterclockwise), 92°/108°, 46°/56°, and 39°/51°, respectively, when their ends were rotated to an angle of 180°. Venn reusable and Boussignac bougies could be rotated in the endotracheal tube by clinically acceptable rotational force. Manikin study: Times to intubation with Venn reusable [25 (SD, 5) s] and Boussignac bougies [35 (6) s] were significantly shorter than with Portex single-use [61 (17) s] and Frova bougies [69 (22) s] (P < 0.01). There were no significant differences in success rate between the four bougies.ConclusionsVenn reusable and Boussignac bougies are a useful aid for intubation with an AWS. Portex single-use and Frova bougies seem to be less suitable for this technique. Different bougies may be of varying utility when used with an AWS or airway device with an endotracheal tube channel.

Cascaded multilevel inverter based on symmetric–asymmetric DC sources with reduced number of components

This study presents a new module for multilevel inverters with reduced components. Each module produces 25 levels using four asymmetrical DC voltage sources (two 1V DC and two 5V DC sources) and 10 semiconductor switches. A significant advantage of the suggested module is its potentiality in producing voltage levels with negative polarity without any end side H-bridge inverter. Therefore, switches with lower voltage ratings are used in its structure. Series connection of the proposed structure leads to a modular topology which produces more voltage levels using reasonable number of switches, gate driver circuits, power diodes and less DC voltage sources. These advantages are analysed by comparing this structure with other state-of-the-art topologies. Selective harmonic elimination pulse width modulation (SHE-PWM) scheme is used to achieve output voltage with high quality. To produce all voltage levels, two algorithms are proposed to determine DC voltage sources magnitude. The accuracy of the suggested module performance in producing all voltage levels is verified by simulation and experimental results.

A Cooperative Control Algorithm for Multiple SVRs Using Correlation of Measurement Data of Distribution Line

SUMMARYIn this paper, a cooperative control algorithm for multiple step voltage regulator (SVR) using correlation of measurement data of distribution line is proposed. Conventionally, the control time constant of a SVR placed on the feeder end side was set slower than a SVR placed on the substation side. The unnecessary tap movement of SVR was reduced by this setting. In this case, on the condition that “the photovoltaic power generation output of the feeder end fluctuates” and “only SVR of the end side works”, it is a problem that control of SVR becomes slow. By the proposed method, the SVR settled in end side of a feeder can change its tap rapidly only if the SVR settled in sending side of a feeder will not change its tap by using proposed method. The features of the method are followings: (1) to estimate tap change possibility of the sending side SVR using correlation model of both of the SVR, (2) only use local measurement data of the SVRs for tap change control. By the proposed method, unnecessary tap change operation and lag of tap control are reduced without communication networks.

End-To-Side versus Side-To-Side Anastomosis in Upper Limb Arteriovenous Fistula for Dialysis Access: A Systematic Review and a Meta-Analysis

An arteriovenous fistula (AVF) is the best modality for hemodialysis access. The end-to-side (ETS) technique has been suggested in the literature to produce superior results to the side-to-side (STS) approach; however, in the absence of a systematic review, this practice remains debatable. Online search for randomized controlled trials and observational studies that compared the ETS versus the STS anastomosis techniques in creating an upper limb AVF. Aims were to systematically assess the difference between both procedures in terms of access maturation, patency, and postoperative complications. Seven studies were included with 463 patients in the ETS group and 523 in the STS group. The difference between the 2 techniques was not significant in relation to patency rates at 3, 6, 12, and 24months (P values: 0.28, 0.82, 0.54, and 0.21, respectively). There were fewer cases of postoperative hematoma in the ETS group; however, the difference was not significant (P=0.09). Arterial steal syndrome was found to be significantly associated with the STS configuration in pooled analysis (pooled risk ratio=0.11 [0.01-0.88], 95% CI, P=0.04). Similar maturation rates between ETS and STS fistula configuration, however, arterial steal syndrome was significantly associated with the STS technique. ETS will likely remain as the preferred AVF configuration as it is less technically demanding.

Effects of FK1706 on nerve regeneration and bladder recovery after spinal cord injury

Objective To investigate the effects of FK1706 on nerve regeneration and bladder function recovery after spinal cord injury in rats. Methods Thirty adult male SD rats weighing 230-250 g were randomly divided into three groups for different treatments: FK1706 group, neurorrhaphy group and control group (10 rats each group). In FK1706 group, the spinal cords were transected in the level of L5 to make rat spinal injury model. Then the distal stump of L6VR was sutured to the lateral face of L4 ventral root (L4VR) in an end-to-side (ETS) fashion under microscope. FK1706 (0.3 mg/kg) was administrated subcutaneously for 5 consecutive days per week for a total of 8 weeks after neurorrhaphy. In neurorrhaphy group, the same operation as FK1706 group was performed but without FK1706 applied after surgery. In control group, left ventral and dorsal roots of L5, L6, S1 and S2 were transected but the left L6VR was preserved as normal control. After four months, FG and FB were injected into left major pelvic ganglion (MPG) and sciatic nerve (SN), respectively, for retrograde nerve tracing to ascertain whether neural pathway was established after surgery. The left L6VR distal to coaptation was harvested for semi-thin sectioning and toluidine blue staining to count the number of myelinated axons. Urodynamic parameters such as maximum detrusor pressure (MDP) and residual urine volume (RUV) were measured in rats through BL-420 biological experimental system. Results The neural pathways were successfully established between left L4VR and L6VR in FK1706 group and neurorrhaphy group through retrograde nerve tracing. The number of regenerated myelinated axons of left L6VR distal to coaptation in FK1706 group and neurorrhaphy group was 535.7±45.2 and 337.4±56.5, respectively, which had a significant difference (P=0.000). The MDP and RUV were (44.6±6.7) mmHg (1 mmHg=0.133 kPa) and (1.16±0.24) ml in FK1706 group, respectively, when the left L4VR proximal to coaptation was stimulated by BL-420 experimental system. The MDP and RUV were (32.5±5.4) mmHg and (2.36±0.34) ml in neurorrhaphy group, respectively. There were statistically significant differences in the MDP and RUV between the two groups (P=0.000). Conclusion The effects of nerve regeneration and bladder function recovery could be evidently enhanced by FK1706 after neurorrhaphy in rat spinal cord injury model. Key words: FK1706; Spinal cord injury; Nerve regeneration; Functional recovery

End-to-side versus end-to-end neurorrhaphy at the peroneal nerve in rats

To evaluate three different kinds of neurorrhaphy of the peroneal nerve. Eigthy rats were divided into 5 groups. Control: nerve had no intervention. End-to-end (EE): nerve was cut and elongated with a nerve graft with two end-to-end neurorrhaphies. End-to-side (ES): nerve was cut and sutured to the graft with at the lateral side of the nerve. Side-to-end (SE): the nerve was cut and sutured to the graft with end-to-end neurorrhaphy. Denervated: nerve was cut and both endings were buried into the muscle. The evaluation was done by walking track analysis, electrophysiology, body mass, cranial tibial muscle mass, nerve and muscle fibers morphometry. The EE, ES and SE have the same potential of reinnervation. There is no functional or histological difference between these different types of neurorrhaphy.

Optimization of loading ratio of ErN as regenerator of 4K-GM cryocooler

High purity erbium nitride (ErN) spheres with the size range of 150-180 µm and 180-212 µm were prepared by nitriding Er metal spheres with low oxygen content. The initial regenerator material of HoCu2 on the cold end of the second regenerator column in 4K-GM cryocooler with nominal cooling power of 0.1 W at 4.2 K was replaced by ErN with different sizes. Higher cooling power was obtained when ErN of smaller size with lower oxygen content was used. We investigated the effect of partial replacement of HoCu2 by ErN in the cold end side of second stage regenerator column on cooling power of 4K-GM cryocoolers. When ErN were substituted for 20 % of HoCu2, the cooling power at 4.2 K reached 0.318 W. This value was 1.36 times as high as that of the cooling power of the GM cryocooler with commercially available regenerator arrangement. Therefore, use of ErN regenerator materials leads to the energy-saving and downsizing of 4K-GM cryocoolers.

Antecubital arteriovenous fistula in hemodialysis; a comparison between side-to-side versus end-to-side venous anastomosis

Introduction: Chronic Kidney Disease (CKD) is a global health problem which is growing in prevalence. Hemodialysis is the most common treatment for end-stage renal disease (ESRD) which requires a permanent vascular access. Vascular accesses should have a good patency and low complication. Objectives: The present study aimed to compare side-to-side (STS) versus end-to-side (ETS) methods in antecubital arteriovenous fistulas in dialysis patients. Patients and Methods: In this randomized, single-blind clinical trial, 100 ESRD patients who scheduled for hemodialysis were divided into two groups. STS arteriovenous anastomosis was employed in one group and in the other, the ETS approach was conducted. Follow ups were done after 1, 8, and 24 weeks to detect fistula maturation and immediate or delayed complications. Results: The STS anastomosis group demonstrated higher rates of delayed maturation, vascular aneurism, and venous hypertension syndrome than ETS anastomosis group. The ETS group, however, showed higher rates of venous thrombosis and vascular stenosis. Overall, the rate of complications was 24% and 8% for STS and ETS anastomosis group respectively (P =0.03). Conclusion: In comparison, ETS arteriovenous fistulas involve less complications than STS method in ESRD patients. However, more thrombosis and stenosis detected by ETS method. ETS arteriovenous fistulas had less delayed maturation, aneurism, venous hypertension and overall complications than STS approach. ETS arteriovenous fistulas contributes to establishing a more stable connection to hemodialysis machine to conduct a more effective hemodialysis.