Half Of Duration Research Articles

A Rare Case of Cutaneuos Angioleiomyoma: A Case Report

Cutaneous Angioleiomyoma is a very rare benign tumour of which incidence is unknown. We report a case of a 42-year-old male patient who presented with a symptomless solitary nodule over the left nostril for one and a half years duration. Complete surgical excision of the tumour was done and the sample was sent for histopathological examination. Diagnosis of this tumour was done on the evidence of histopathological examination with haematoxylin and eosin mounts. Sometimes achieving the best aesthetically accepted results may be challenging due to the site of involvement.

A planar plume array emanating from an atmospheric pressure argon plasma jet employing floating electrodes

Large-scale plasma plumes downstream of plasma jets are in urgent need from a practical viewpoint. In this Letter, an argon plasma jet with floating electrodes is proposed to produce a large-scale planar plume array. Results indicate that with increasing peak voltage (Vp), the planar plume array elongates gradually and scales up in the lateral direction to an optimal value of 90.0 mm. There is only one discharge pulse per voltage half cycle, whose intensity and duration increase with increasing Vp. Moreover, there is a time lag between the initiations of individual plumes. Fast photography reveals that the planar plume array originates from the repeated process of some micro-discharge filaments stretching along the argon stream. By optical emission spectroscopy, the spatial distribution of plasma parameters is obtained, such as electron density, electron temperature, and gas temperature. At last, the planar plume array is employed to test the surface modification of polyethylene terephthalate, for which a uniform modification has been realized with a scan velocity of 1.0 cm/min. These results are of great significance for the development of large-scale atmospheric pressure plasma sources.

DIAGNOSTIC UTILITY OF BREAST FNAC IN THE EVALUATION OF PALPABLE MASSES - A TERTIARY CENTRE STUDY

Background: The purpose of the study was to evaluate the cytological features of palpable breast masses and to advocate the utility of breast FNAC . Material And Methods: Aretrospective study of one and a half years duration was conducted in the Department of Pathology of a tertiary care hospital which included 110 patients with palpable breast masses. Histopathological correlation in 110 cases was obtained and diagnostic efcacy calculated by sensitivity, specicity, poisitive predictive value (PPV) and negative predictive values (NPV). Results: Cytological diagnosis was rendered in 110 patients with age group ranging from 15 to 68 years. Breast lesions commonly presented in upper inner quadrant (48%) of both breasts. Aspirates were diagnosed as non-neoplastic in 15 lesions (13.6%) and neoplastic in 95 lesions (86.36%) [benign 65.45%, and malignant 20.9%]. There were two false positives and one false negative, with 96.83% specicity, 97.87% sensitivity, PPV 95.83%, NPV 98.39%, and diagnostic efcacy of 97.27% for the palpable breast lesions respectively. Conclusion: FNAC is a rapid and economical procedure with high accuracy for cytological diagnoses of breast masses and helps the surgeon to plan for further treatment.

Strengthening of Fire Damaged, Light Weight, High Strength Reinforced Concrete Beam Using SIFCON Jacket

This study aims to extrapolate the behavior of lightweight (LECA) high strength concrete beams subjected to high temperatures. the LECA aggregate was utilized as coarse fraction in the reference mixture. a post development process in terms of jacketing the fire damaged beams with SIFCON materials layer was also investigated. In addition to the reference samples, various parameters of concrete beams and conditioning were conducted, namely, fire duration exposure, concrete cover, and SIFCON layer thickness. In details, two concrete cover thickness, half and one-hour fire duration exposure, and two SIFCON layer thicknesses were the main parameters in this study. the thermal gradient through the beam cross section was captured through installing thermocouples sensors embedded inside at various location. The physical and chemical properties were tested for all used materials in this study. Overall, fourteen concrete beam samples were tested for all the three phases (normal or reference, fire damaged samples, and post enhancement with SIFCON jacket). the level of comparison for the tested samples was focused on several parameters are; maximum shear load capacity and corresponded displacement, ductility index, cracking load, initial and secant stiffness, and energy absorption. The experimental test results under the scope of this research have shown significant improvement for the strengthened beams were observed compared with the damaged samples. Moreover, the results have cleared that the strengthened beams, in term of the mentioned indices were recovered as and comparable to the undamaged (reference beam), except the absorption energy. Where further studies and efforts have to be paid to overcome such issue.

Autonomic Regulation of the Goldfish Intact Heart.

Autonomic regulation plays a central role in cardiac contractility and excitability in numerous vertebrate species. However, the role of autonomic regulation is less understood in fish physiology. Here, we used Goldfish as a model to explore the role of autonomic regulation. A transmural electrocardiogram recording showed perfusion of the Goldfish heart with isoproterenol increased the spontaneous heart rate, while perfusion with carbamylcholine decreased the spontaneous heart rate. Cardiac action potentials obtained via sharp microelectrodes exhibited the same modifications of the spontaneous heart rate in response to isoproterenol and carbamylcholine. Interestingly, the duration of the cardiac action potentials lengthened in the presence of both isoproterenol and carbamylcholine. To evaluate cardiac contractility, the Goldfish heart was perfused with the Ca2+ indicator Rhod-2 and ventricular epicardial Ca2+ transients were measured using Pulsed Local Field Fluorescence Microscopy. Following isoproterenol perfusion, the amplitude of the Ca2+ transient significantly increased, the half duration of the Ca2+ transient shortened, and there was an observable increase in the velocity of the rise time and fall time of the Ca2+ transient, all of which are compatible with the shortening of the action potential induced by isoproterenol perfusion. On the other hand, carbamylcholine perfusion significantly reduced the amplitude of the Ca2+ transient and increased the half duration of the Ca2+ transient. These results are interesting because the effect of carbamylcholine is opposite to what happens in classically used models, such as mouse hearts, and the autonomic regulation of the Goldfish heart is strikingly similar to what has been observed in larger mammalian models resembling humans.

Increased excitability of human iPSC-derived neurons in HTR2A variant-related sleep bruxism

Sleep bruxism (SB) is a sleep-related movement disorder characterized by grinding and clenching of the teeth during sleep. We previously found a significant association between SB and a single nucleotide polymorphism (SNP), rs6313, in the neuronal serotonin 2A receptor gene (HTR2A), and established human induced pluripotent stem cell (iPSC)-derived neurons from SB patients with a genetic variant. To elucidate the electrophysiological characteristics of SB iPSC-derived neural cells bearing an SB-related genetic variant, we generated ventral hindbrain neurons from SB patients and unaffected controls, and explored the intrinsic membrane properties of these neurons using the patch-clamp technique. We found that the electrophysiological properties of iPSC-derived neurons mature in a time-dependent manner in long-term control cultures. SB neurons exhibited higher action potential firing frequency, higher gain, and shorter action potential half duration. This is the first in vitro modeling of SB using patient-specific iPSCs. The revealed electrophysiological characteristics may serve as a benchmark for further investigation of pathogenic mechanisms underlying SB. Moreover, our results on long-term cultures provide a strategy to define the functional maturity of human neurons in vitro, which can be implemented for stem cell research of neurogenesis, and neurodevelopmental disorders.

Power Quality Phenomena, Standards, and Proposed Metrics for DC Grids

This work addresses the problem of power quality (PQ) metrics (or indexes) suitable for DC grids, encompassing low and medium voltage applications, including electric transports, all-electric ships and aircrafts, electric vehicles, distributed generation and microgrids, modern data centers, etc. The two main pillars on which such PQ indexes are discussed and built are: (i) the physical justification, so the electric phenomena affecting DC grids and components (PV panels, fuel cells, capacitors, batteries, etc.), causing, e.g., stress of materials, aging, distortion, grid instability; and (ii) the existing standardization framework, pointing out desirable coverage and extension, similarity with AC grids standards, but also inconsistencies. For the first point, each phenomenon is discussed with quantitative conclusions on relevant thresholds: in many cases some percentage of distortion (ripple) is acceptable (stress on capacitors and storage, impact on fuel cells, and PV panels), whereas in other cases, much higher levels may be tolerated (interference to protection and monitoring devices). Standards are reviewed for indications not only of low-order harmonics and voltage fluctuations typical of old DC grid schemes, but also for high-frequency noise, including thus supraharmonics and common-mode disturbance, and filling the gap with the electromagnetic compatibility domain. However, phenomena typical of EMC and electrical safety (such as various types of overvoltages and fast transients) are excluded. Suitable PQ indexes are then reviewed, suggesting integrations and modifications, to cover the relevant phenomena and technological progress, and to better follow the normative exigencies: ripple is considered in time and frequency domain, in particular with a band limited implementation; for transients and pulsed loads, more traditional indexes based on area, energy, and half duration are confronted with indexes evaluating the power trajectory and its derivative.

Electrical properties and synaptic transmission in mouse intracardiac ganglion neurons in situ.

The intrinsic cardiac nervous system represents the final site of signal integration for neurotransmission to the myocardium to enable local control of cardiac performance. The electrophysiological characteristics and ganglionic transmission of adult mouse intrinsic cardiac ganglion (ICG) neurons were investigated using a whole‐mount ganglion preparation of the excised right atrial ganglion plexus and intracellular microelectrode recording techniques. The passive and active electrical properties of ICG neurons and synaptic transmission including synaptic response strength and efficacy as a function of stimulation frequency were examined. The resting membrane potential and input resistance of ICG neurons were −47.9 ± 4.0 mV and 197.2 ± 81.5 MΩ, respectively. All neurons had somatic action potentials with overshoots of >+15 mV and after‐hyperpolarizations having an average of 10 mV amplitude and ~45 ms half duration. Phasic discharge activities were recorded from the majority of neurons studied and several types of excitatory synaptic responses were recorded following inputs from the vagus or interganglionic nerve trunk(s). Most postganglionic neurons (>75%) received a strong, suprathreshold synaptic input and reliably followed high‐frequency repetitive nerve stimulation up to at least 50 Hz. Nerve‐evoked synaptic transmission was blocked by extracellular Cd2+, ω‐conotoxin CVIE, or α‐conotoxin RegIIA, a selective α3‐containing nicotinic acetylcholine receptor antagonist. Synaptic transmission and the electrical properties of murine ICG neurons contribute to the pattern of discharge which regulates chronotropic, dromotropic, and inotropic elements of cardiac function.

Win, Draw, or Lose? Global Positioning System-Based Variables' Effect on the Match Outcome: A Full-Season Study on an Iranian Professional Soccer Team.

The aim of the study was to determine the between-match and between-halves match variability of various Global Positioning System (GPS) variables and metabolic power average (MPA) in competitions, based on the match results obtained by professional soccer players over a full season. Observations on individual match performance measures were undertaken on thirteen outfield players competing in the Iranian Premier League. The measures selected for analysis included total duration, accelerations in zones (AccZ1, 2, and 3), decelerations in zones (DecZ1, 2, and 3), and MPA collected by the Wearable Inertial Measurement Unit (WIMU). The GPS manufacturer set the thresholds for the variables analyzed as follows: AccZ1 (<2 m·s−2); AccZ2 (2 to 4 m·s−2); AccZ3 (>4 m·s−2); DecZ1 (<−2 m·s−2); DecZ2 (−2 to −4 m·s−2); DecZ3 (>−4 m·s−2). The results revealed significant differences between wins and draws for the duration of the match and draws compared to wins for the first- half duration (p ≤ 0.05; ES = 0.36 [−0.43, 1.12]), (p ≤ 0.05; ES = −7.0 [−8.78, −4.78], respectively. There were significant differences on AccZ1 during the first-half between draws and defeats (p ≤ 0.05; ES = −0.43 [−1.32, 0.46]), for AccZ3 in the second-half between draws and defeats (p ≤ 0.05; ES = 1.37 [0.48, 2.25]). In addition, there were significant differences between wins and draws (p ≤ 0.05; ES = 0.22 [−0.62, 1.10]), and wins and defeats for MPA in the first- half (p ≤ 0.05; ES = 0.34 [−0.65, 1.22]). MPA showed further differences between draws and defeats in the second- half (p ≤ 0.05; ES = 0.57 [−0.22, 1.35]). Descriptive analysis revealed differences between the first and second half for wins in AccZ2 (p = 0.005), DecZ2 (p = 0.029), and MPA (p = 0.048). In addition, draws showed significant differences between the first and second half in duration, AccZ1, AccZ2, and DecZ2 (p = 0.008), (p = 0.017), (p = 0.040), and (p = 0.037) respectively. Defeats showed differences between the first and second half in AccZ1, AccZ3, and MPA (p = 0.001), (p = 0.018), and (p = 0.003) respectively. In summary, the study reveals large variations between the match duration, accelerometer variables, and MPA both within and between matches. Regardless of the match outcome, the first half seems to produce greater outputs. The results should be considered when performing a half-time re-warm-up, as this may be an additional factor influencing the drop in the intensity markers in the second half in conjunction with factors such as fatigue, pacing strategies, and other contextual variables that may influence the results.

Re-testing theories of vowel inherent spectral change

Three basic models of vowel inherent spectral change have been proposed: onset + offset, onset + direction, and onset + slope (or spectral rate of change). Morrison (2013) presents three theoretical stimuli whose identification rates relative to each other should lend weight to one of these hypotheses: (i) canonical duration and canonical onset-to-offset trajectory, (ii) canonical duration with double trajectory length, and (iii) canonical trajectory with half duration. The bulk of previous work supports onset + offset. In the present study, eight English monophthongs were synthesized with the Klatt synthesizer of the Berkeley Phonetics Machine. Three versions of each vowel were synthesized, corresponding to the theoretical stimuli of Morrison (2013). These 24 stimuli were used in two studies (n= 18 for each). First was a vowel identification task, where the choices were [hVd] words with the chosen vowels ( heed, hid, etc.). Second was a goodness rating task with a 7-point Likert scale, where participants were played a vowel stimulus while being shown the orthographic [hVd] word containing that vowel. The results do not fully support any one theory, but they align most closely with the onset + direction hypothesis, with onset + offset also being supported.

Excitation-Contraction Coupling in the Goldfish (Carassius auratus) Intact Heart.

Cardiac physiology of fish models is an emerging field given the ease of genome editing and the development of transgenic models. Several studies have described the cardiac properties of zebrafish (Denio rerio). The goldfish (Carassius auratus) belongs to the same family as the zebrafish and has emerged as an alternative model with which to study cardiac function. Here, we propose to acutely study electrophysiological and systolic Ca2+ signaling in intact goldfish hearts. We assessed the Ca2+ dynamics and the electrophysiological cardiac function of goldfish, zebrafish, and mice models, using pulsed local field fluorescence microscopy, intracellular microelectrodes, and flash photolysis in perfused hearts. We observed goldfish ventricular action potentials (APs) and Ca2+ transients to be significantly longer when compared to the zebrafish. The action potential half duration at 50% (APD50) of goldfish was 370.38 ± 8.8 ms long, and in the zebrafish they were observed to be only 83.9 ± 9.4 ms. Additionally, the half duration of the Ca2+ transients was also longer for goldfish (402.1 ± 4.4 ms) compared to the zebrafish (99.1 ± 2.7 ms). Also, blocking of the L-type Ca2+ channels with nifedipine revealed this current has a major role in defining the amplitude and the duration of goldfish Ca2+ transients. Interestingly, nifedipine flash photolysis experiments in the intact heart identified whether or not the decrease in the amplitude of Ca2+ transients was due to shorter APs. Moreover, an increase in temperature and heart rate had a strong shortening effect on the AP and Ca2+ transients of goldfish hearts. Furthermore, ryanodine (Ry) and thapsigargin (Tg) significantly reduced the amplitude of the Ca2+ transients, induced a prolongation in the APs, and altogether exhibited the degree to which the Ca2+ release from the sarcoplasmic reticulum contributed to the Ca2+ transients. We conclude that the electrophysiological properties and Ca2+ signaling in intact goldfish hearts strongly resembles the endocardial layer of larger mammals.

RT-03 POSTOPERATIVE CYBERKNIFE HYPOFRACTIONATED RADIOTHERAPY FOR THE ELDERLY PATIENTS WITH GLIOBLASTOMA

INTRODUCTIONIn recent years, hypofractionated radiotherapy (HRT) 40Gy in 15 fractions with concomitant temozolomide(TMZ) has come to be used as standard treatment for elderly glioblastoma. However, the treatment duration of 3–4 weeks for radiation is not enough short, and there is also a problem of radiation sickness. We performed hypofractionated stereotactic radiotherapy with CyberKnife (CK) for less than 2weeks. We retrospectively analyzed eight newly diagnosed elderly patients with glioblastoma treated by CK.METHODSSurgical cavity, contrast enhanced lesion, FLAIR high signal intensity area were set as gross tumor volume (GTV). To planned target volume (PTV) as GTV + 2 mm, Marginal dose (D95) 35 Gy in 5 fractions (Fr) was prescribed. The dose prescription and number of fractions were adjusted taking into consideration dose distribution, dose-limiting for important organs such as optic chiasm and brainstem.RESULTSThe eight patients consisted of 3 men and 5 women. The median age was 78 (range 68–84) years old. All patients were pathologically diagnosed as glioblastoma. Two of 8 cases had undergone gross total removal of contrast area. Median postoperative KPS was 70 (40–80). Thirty three (28–33.5) Gy was administered in 5 (3–10) Fr to PTV 117 (44–243) ml. TMZ was used in 7 patients. Bevacizumab (BEV) was used together from 4 weeks after surgery in 5 patients. Progression-free survival was 6.5 (2.9–10.6) months and overall survival was 17.5 (7.1–28.5) months. 7 patients had experienced controllable hypertension with antihypertensive agents, Two patients had suffered from deep vein thrombosis, and anticoagulation therapy was used. One patient had nausea and malaise due to TMZ and had continue BEV alone. Asymptomatic cerebral infarction in the radiation field was observed in a patient.CONCLUSIONCK treated in less than half duration of conventional HRT is expected as less invasive treatment.

Real-time evaluation of an image analysis system for monitoring surgical hemoglobin loss.

Monitoring blood loss is important for management of surgical patients. This study reviews a device (Triton) that uses computer analysis of a photograph to estimate hemoglobin (Hb) mass present on surgical sponges. The device essentially does what a clinician does when trying to make a visual estimation of blood loss by looking at a sponge, albeit with less subjective variation. The performance of the Triton system is reported upon in during real-time use in surgical procedures. The cumulative Hb losses estimated using the Triton system for 50 enrolled patients were compared with reference Hb measurements during the first quarter, half, three-quarters and full duration of the surgery. Additionally, the estimated blood loss (EBL) was calculated using the Triton measured Hb loss and compared with values obtained from both visual estimation and gravimetric measurements. Hb loss measured by Triton correlated with the reference method across the four measurement intervals. Bias remained low and increased from 0.1g in the first quarter to 3.7g at case completion. The limits of agreement remained narrow and increased proportionally from the beginning to the end of the cases, reaching a maximum range of -15.3 to 22.7g. The median (IQR) difference of EBL derived from the Triton system, gravimetric method and visual estimation versus the reference value were 13 (74), 389 (287), and 4 (230)mL, respectively. Use of the Triton system to measure Hb loss in real-time during surgery is feasible and accurate.

Spatiotemporal Profiles of Proprioception Processed by the Masseter Muscle Spindles in Rat Cerebral Cortex: An Optical Imaging Study.

Muscle spindles in the jaw-closing muscles, which are innervated by trigeminal mesencephalic neurons (MesV neurons), control the strength of occlusion and the position of the mandible. The mechanisms underlying cortical processing of proprioceptive information are critical to understanding how sensory information from the masticatory muscles regulates orofacial motor function. However, these mechanisms are mostly unknown. The present study aimed to identify the regions that process proprioception of the jaw-closing muscles using in vivo optical imaging with a voltage-sensitive dye in rats under urethane anesthesia. First, jaw opening that was produced by mechanically pulling down the mandible evoked an optical response, which reflects neural excitation, in two cortical regions: the most rostroventral part of the primary somatosensory cortex (S1) and the border between the ventral part of the secondary somatosensory cortex (S2) and the insular oral region (IOR). The kinetics of the optical signal, including the latency, amplitude, rise time, decay time and half duration, in the S1 region for the response with the largest amplitude were comparable to those in the region with the largest response in S2/IOR. Second, we visualized the regions responding to electrical stimulation of the masseter nerve, which activates both motor efferent fibers and somatosensory afferent fibers, including those that transmit nociceptive and proprioceptive information. Masseter nerve stimulation initially excited the rostral part of the S2/IOR region, and an adjacent region responded to jaw opening. The caudal part of the region showing the maximum response overlapped with the region responding to jaw opening, whereas the rostral part overlapped with the region responding to electrical stimulation of the maxillary and mandibular molar pulps. These findings suggest that proprioception of the masseter is processed in S1 and S2/IOR. Other sensory information, such as nociception, is processed in a region that is adjacent to these pulpal regions and is located in the rostral part of S2/IOR, which receives nociceptive inputs from the molar pulps. The spatial proximity of these regions may be associated with the mechanisms by which masseter muscle pain is incorrectly perceived as dental pain.

Influence of AC voltage on the positive DC corona current pulses in a wire-cylinder gap View Document

In the development of hybrid HVDC and HVAC transmission lines, the study of radio interference is an important issue. Positive corona current pulses from high voltage transmission lines are the main source of radio interference. In this paper, the design of a wire-cylinder gap electrode system is presented to study the influence of AC voltage on the characteristics of positive corona current pulses. The study shows that the mode of the current pulses is different from that of either DC or AC corona discharge. Waveform parameters of the pulses, such as rise time, half wave time, duration time, repetition rates, average amplitude, and time intervals of secondary pulses are all statistically analyzed in this study. The empirical formulas for the repetition rates with different AC voltages are presented. A theoretical explanation based on an ion cloud model is given to reveal the mechanism behind the influence of AC voltage on positive corona discharge. The experimental results could provide some references for the prediction of radio interference from hybrid AC/DC transmission lines.

Endurance Performance during Severe-Intensity Intermittent Cycling: Effect of Exercise Duration and Recovery Type.

Slow component of oxygen uptake (VO2SC) kinetics and maximal oxygen uptake (VO2max) attainment seem to influence endurance performance during constant-work rate exercise (CWR) performed within the severe intensity domain. In this study, it was hypothesized that delaying the attainment of VO2max by reducing the rates at which VO2 increases with time (VO2SC kinetics) would improve the endurance performance during severe-intensity intermittent exercise performed with different work:recovery duration and recovery type in active individuals. After the estimation of the parameters of the VO2SC kinetics during CWR exercise, 18 males were divided into two groups (Passive and Active recovery) and performed at different days, two intermittent exercises to exhaustion (at 95% IVO2max, with work: recovery ratio of 2:1) with the duration of the repetitions calculated from the onset of the exercise to the beginning of the VO2SC (Short) or to the half duration of the VO2SC (Long). The active recovery was performed at 50% IVO2max. The endurance performance during intermittent exercises for the Passive (Short = 1523 ± 411; Long = 984 ± 260 s) and Active (Short = 902 ± 239; Long = 886 ± 254 s) groups was improved compared with CWR condition (Passive = 540 ± 116; Active = 489 ± 84 s). For Passive group, the endurance performance was significantly higher for Short than Long condition. However, no significant difference between Short and Long conditions was found for Active group. Additionally, the endurance performance during Short condition was higher for Passive than Active group. The VO2SC kinetics was significantly increased for CWR (Passive = 0.16 ± 0.04; Active = 0.16 ± 0.04 L.min−2) compared with Short (Passive = 0.01 ± 0.01; Active = 0.03 ± 0.04 L.min−2) and Long (Passive = 0.02 ± 0.01; Active = 0.01 ± 0.01 L.min−2) intermittent exercise conditions. No significant difference was found among the intermittent exercises. It can be concluded that the endurance performance is negatively influenced by active recovery only during shorter high-intensity intermittent exercise. Moreover, the improvement in endurance performance seems not be explained by differences in the VO2SC kinetics, since its values were similar among all intermittent exercise conditions.

Solitary Fibrous Tumour: An Unusual Nasal Cavity Tumour

Objective: To describe the diagnosis and management of an unusual case of solitary fibrous tumor of nasal cavity. Methods: The case records of a patient with solitary fibrous tumor of nasal cavity were reviewed. Results: This patient presented with constant nasal obstruction of one and a half years duration. Nasal endoscopy revealed a firm polypoidal mass filling the left nasal cavity medial to middle turbinate. After imaging, she underwent endoscopic excision of the mass which on histopathological examination was diagnosed as solitary fibrous tumor. At follow up after one year, there was no recurrence of tumour. Conclusion: Solitary fibrous tumours are infrequent neoplasms of mesenchymal origin presenting as a well circumscribed, avidly enhancing mass that is iso- to hyperintense on T1W and T2W MRI images. Even though most SFTs are benign, some of these tumors can be locally invasive and have the potential to be malignant. Surgical excision with long term follow up is the treatment of choice.

Effect of D.C. electric field on salt bath nitriding for 35 steel and kinetics analysis

A rapid salt bath nitriding technology was primarily developed by additionally applying direct current (D.C.) electric field on the basis of traditional technique (NM). Characterization of the modified surface layers was made by means of optical microscopy, Vickers micro-hardness test and X-ray diffraction analysis. The results showed that D.C. electric field could significantly enhance the nitriding efficiency and the enhancement effect was closely related to the intensity of D.C. electric field. By applying D.C electric field of 7.5V, even a little thicker compound layer could be obtained at only half duration of that in traditional technique, and the thickness of compound layer increased more than 60%, from 18μm up to 29μm at the same treating temperature of 848K and holding duration of 100min. Meanwhile, higher surface hardness, modestly higher sub-surface hardness and superior hardness profile were obtained assisted by D.C. electric field. It was also found that the diffusion coefficient of nitrogen was increased more than 1.9 times and activation energy was decreased from 184kJ/mol to 159kJ/mol enhanced by D.C. electric field. The possible enhancement mechanism is that D.C. electric field can promote chemical reactions and produce more active nitrogen atoms in the salt bath, positively charge the active atoms and force them diffuse directionally toward the surface of the treated specimen, and hence significantly improve the efficiency of the active atoms in the salt bath.

The role of posterior parietal cortices on prismatic adaptation effects on the representation of time intervals

Previous studies provided evidence of an ascending left-to-right spatial representation of time durations by using a technique affecting high levels of spatial cognition, i.e. prismatic adaptation (PA). Indeed, PA that induced a leftward aftereffect distorted time representation toward an underestimation, while PA that induced a rightward aftereffect distorted time representation toward an overestimation. The present study advances previous findings on the effects of PA on time by investigating the neural basis subtending these effects. We focused on the posterior parietal cortex (PPC) since it is involved in the PA procedure and also in the formulation of the spatial representation of time. We conducted two experiments where right-handed healthy adults were submitted to a time task, before and after PA, that could induce a leftward or rightward aftereffect. Repetitive TMS (rTMS) was used to inhibit the left or right PPC before PA administration. In a first experiment the time task consisted of reproducing an half duration (time bisection task) by pressing a key and the participants responded and adapted to prisms with their right hand. In a second experiment the time task consisted of reproducing a whole duration (time reproduction task) by pressing a key and the participants responded and adapted to prisms with their left hand.We found an abolition of the effects of PA on time when rTMS was delivered on the left and not on the right PPC, regardless of the task and moreover, when the participants responded and adapted with the right hand and also with the left hand. This result suggests a direct involvement of the left PPC in the interactive process, between spatial modulations induced by PA and the spatial representation of time, that does not depend on motor processes. This study provides useful results for future investigations on the neural mechanisms subtending the effects of PA on spatial representations.

Blood Transfusion after Total Knee Arthroplasty; Comparison of Drainage versus Non-Drainage

Introduction: There is no established evidence to support the use of drains after total knee arthroplasty (TKA). The aim of our study was to compare the requirement for blood transfusion after primary total knee arthroplasty with and without the use of closed suction drains and cost analysis of performing routine blood group and save. Material and methods: In this retrospective study, we reviewed the data over 3 and a half years duration including consecutive primary total knee arthroplasties. Patients were divided into drainage and non-drainage groups. Eleven surgeons used drains and two did not use drains. Results: 2497 primary total knee arthroplasties were performed during our study period by 13 surgeons. Postoperatively 7.5% patients (n=189) received blood transfusion. In the drainage group (n=2271), 7.3% patients (n=167) received transfusion with mean preoperative Hb of 12.1 g/dl (9.1 to 15.8 g/dl) and mean postoperative Hb of 7.9 g/dl (5.1 to 8.8 g/dl). In the non-drainage group (n=226), 9.7% patients (n=22) received transfusion with mean preoperative Hb of 12.1 g/dl (8.9 to 14.4 g/dl) and mean postoperative Hb of 7.7 g/dl (6.0 to 8.5 g/dl). Blood samples for 92.5% patients remained unused and eventually wasted. Annual cost of performing routine group and save for TKA patients at the time of our study in our department was nearly £20,000 and the annual cost of using drains for these patients was £51,000. Conclusion: We did not find any significant difference in blood transfusion requirement in the two groups. Selective group and save in these patients may prove to be cost-effective.