Multi-fidelity modelling of shark skin denticle flows: insights into drag generation mechanisms.

We investigate the flow over smooth (non-ribletted) shark skin denticles in an open-channel flow using direct numerical simulation (DNS) and two Reynolds averaged Navier-Stokes (RANS) closures. Large peaks in pressure and viscous drag are observed at the denticle crown edges, where they are exposed to high-speed fluid which penetrates between individual denticles, increasing shear and turbulence. Strong lift forces lead to a positive spanwise torque acting on individual denticles, potentially encouraging bristling if the denticles were not fixed. However, DNS predicts that denticles ultimately increase drag by 58% compared to a flat plate. Good predictions of drag distributions are obtained by RANS models, although an underestimation of turbulent kinetic energy production leads to an underprediction of drag. Nevertheless, RANS methods correctly predict trends in the drag data and the regions contributing most to viscous and pressure drag. Subsequently, RANS models are used to investigate the dependence of drag on the flow blockage ratio (boundary layer to roughness height ratio), finding that the drag increase due to denticles is halved when the blockage ratio δ/h is increased from 14 to 45. Our results provide an integrated understanding of the drag over non-ribletted denticles, enabling existing diverse drag data to be explained.

Impact of blood donor characteristics on quality of packed red blood cell concentrates.

INTRODUCTION: Impact of blood donor characteristics on quality of packed red blood cell concentrates. OBJECTIVE: To determine the impact of donor factors on the quality of packed red blood cell concentrates. MATERIAL AND METHODS: The analytical cross sectional study was conducted on 505 whole blood donors after approval by the Institutional Ethics Committee and written informed consent from blood donors. Two mL EDTA sample was collected for pre-donation haemoglobin estimation and all relevant donor details were recorded. Whole blood was collected in 350mL double blood bags. PRBCs were prepared as per the departmental SOP. Volume of each PRBC was recorded and sample from each bag was taken for estimation of total haemoglobin content and haematocrit. RESULTS: Of 505 blood donors, 459 (90.9%) were males and 324 donors (64.2%) were less than 30 years of age. The majority of the donors were repeat donors (61%, n=308 repeat donors), vegetarians (52.9%, n=267 vegetarians) and non-smokers (92.7%, n=468). Mean haemoglobin was found to be significantly higher in males (14.9 vs. 13.3; P≤0.001), donors more than 30 years of age (15 vs. 14.7; P=0.042), repeat donors (14.9 vs. 14.7), non-vegetarians (15.1 vs. 14.6; P≤0.001) and smokers (15.3 vs. 14.8g/dL; P=0.020). PRBC units prepared from male blood donors, repeat donors and non vegetarians had significantly higher mean volume and mean total haemoglobin content. Strong positive correlation was observed between haemoglobin of the blood donor and total haemoglobin content of the PRBC and volume of blood collected. CONCLUSIONS: Donor characteristics do have effect on total haemoglobin content of packed red blood cells.

Reporting of delayed adverse donor reactions in whole blood donors: Just the tip of an iceberg!

BACKGROUND AND OBJECTIVES: The study was planned to determine the incidence and analyze how various epidemiological factors tend to be associated with delayed adverse donor reactions (ADR). MATERIAL AND METHODS: The prospective observational study was conducted in Department of Transfusion Medicine of tertiary care hospital from January to December 2019. Eligible blood donors were observed for any adverse reactions after 15 minutes of removal of phlebotomy needle. Further, telephonic calls were made to each enrolled blood donor on day-2 and day-7 of the whole blood donation. For each day, two calls were made at an interval of 4 hours before declaring the participant to be non-responder. RESULTS: A total of 1540 (84.1%) blood donors responded on day-2 and 1610 (87.9%) responded on day-7 of follow-up. Total 180 (11.2%) blood donors experienced delayed ADRs. Two donors (1.1%) experienced on-site while 178 (98.89%) reported off-site delayed ADRs when followed-up telephonically. The commonest delayed ADRs reported were bruise (n=72; 30.9%), arm-pain (n=61; 26.2%) and generalised weakness (n=44; 18.9%). Female donors (27.3% vs. 11.2%; P=0.004), first time donors (15.2 vs. 9.9%; P=0.002), donors with low body-weight (range of 45-60kg; 15.9% vs. 11.5% vs. 6.1%; P=0.011) and body mass index<18.5 (24% vs. 12.5% vs. 9.7% vs. 11.3%; P=0.028) experienced more delayed ADRs. CONCLUSION: Blood donors do experience delayed ADRs but these are not reported to the blood centers as these are usually mild. However, it is important to capture these delayed adverse donor reactions and report it to National Hemovigilance Program so that strategies can be formulated to prevent their occurrence and recurrence.

Semiclassical evaluation of expectation values.

Semiclassical mechanics allows for a description of quantum systems which preserves their phase information, and thus interference effects, while using only the system's classical dynamics as an input. In particular one of the strengths of a semiclassical description is to present a coherent picture which (to negligible higher-order ℏ corrections) is independent of the particular canonical coordinates used. However, this coherence relies heavily on the use of the stationary phase approximation. It turns out, however, that in some important cases, a brutal application of stationary phase approximation washes out all interference, and thus quantum, effects. In this paper, we address this issue in detail in one of its simplest instantiations, namely the evaluation of the time evolution of the expectation value of an operator. We explain why it is necessary to include contributions which are not in the neighborhood of stationary points and provide new semiclassical expressions for the evolution of the expectation values. The efficiency of our approach is based on the fact that we treat analytically all the integrals that can be performed within the stationary phase approximation, implying that the remaining integrals are simple integrals, in the sense that the integrand has no significant variations on the quantum scale (and thus they are very easy to perform numerically). This to be contrasted with other approaches such as the ones based on initial value representation, popular in chemical and molecular physics, which avoid a root search for the classical dynamics, but at the cost of performing numerically integrals whose evaluation requires a sampling on the quantum scale, and which are therefore not well designed to address the deep semiclassical regime. Along the way, we get a deeper understanding of the origin of these interference effects and an intuitive geometric picture associated with them.

New sonographic marker of borderline ovarian tumor: microcystic pattern of papillae and solid components.

OBJECTIVE: To describe and evaluate the utility of a new sonographic microcystic pattern, which is typical of borderline ovarian tumor (BOT) papillary projections, solid component(s) and/or septa, as a new ultrasound marker that is capable of distinguishing BOT from other adnexal masses, and to present/obtain histologic confirmation. METHODS: In this retrospective study, we identified women with a histologic diagnosis of BOT following surgical resection who had undergone preoperative transvaginal ultrasound (TVS) examination. All images were reviewed for presence or absence of thin-walled, fluid-filled cluster(s) of 1-3-mm cystic formations, associated with solid component(s), papillary projections and/or septa. From the same cases, histopathologic slides of each BOT were examined for presence of any of these microcystic features which had been identified on TVS. To confirm that the microcystic TVS pattern is unique to BOTs, we also selected randomly from our ultrasound and surgical database 20 cases of epithelial ovarian cancer and 20 cases of benign cystadenoma, for review by the same pathologists. To confirm the novelty of our findings, we searched PubMed for literature published in the English language between 2010 and 2018 to determine whether the association between microcystic tissue pattern and BOT has been described previously. RESULTS: Included in the final analysis were 62 patients (67 ovaries) with preoperative TVS and surgically confirmed BOT on pathologic examination. The mean patient age at surgery was 39.8 years. The mean BOT size at TVS was 60.7 mm. Of the 67 BOTs, 47 (70.1%) were serous, 15 (22.4%) were mucinous and five (7.5%) were seromucinous. We observed on TVS a microcystic pattern in the papillary projections, solid component(s) and/or septa in 60 (89.6%) of the 67 BOTs, including 46 (97.9%) of the 47 serous BOTs, 11 (73.3%) of the 15 mucinous BOTs and three (60.0%) of the five seromucinous BOTs. On microscopic evaluation, 60 (89.6%) of the 67 samples had characteristic 1-3-mm fluid-filled cysts similar to those seen on TVS. In seven cases there was a discrepancy between sonographic and histologic observation of a microcystic pattern. The 20 cystadenomas were mostly unilocular and/or multilocular and largely avascular. None of them or the 20 epithelial ovarian malignancies displayed microcystic characteristics, either on TVS or at histology. On review of 23 published articles in the English medical literature, containing 163 sonographic images of BOT, we found that, while all images contained it, there was no description of the microcystic tissue pattern. CONCLUSION: We report herein a novel sonographic marker of BOT, a 'microcystic pattern' of BOT papillary projections, solid component(s) and/or septa. This was seen in the majority of both serous and mucinous BOT cases. Importantly, based on comparison of sonographic images and histopathology of benign entities and malignancies, the microcystic appearance seems to be unique to BOTs. No similar description has been published previously. Utilization of this new marker should help to identify BOT correctly, discriminating it from ovarian cancer and benign ovarian pathology, and should ensure appropriate clinical and surgical management. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Mapping autosomal recessive intellectual disability: combined microarray and exome sequencing identifies 26 novel candidate genes in 192 consanguineous families.

Approximately 1% of the global population is affected by intellectual disability (ID), and the majority receive no molecular diagnosis. Previous studies have indicated high levels of genetic heterogeneity, with estimates of more than 2500 autosomal ID genes, the majority of which are autosomal recessive (AR). Here, we combined microarray genotyping, homozygosity-by-descent (HBD) mapping, copy number variation (CNV) analysis, and whole exome sequencing (WES) to identify disease genes/mutations in 192 multiplex Pakistani and Iranian consanguineous families with non-syndromic ID. We identified definite or candidate mutations (or CNVs) in 51% of families in 72 different genes, including 26 not previously reported for ARID. The new ARID genes include nine with loss-of-function mutations (ABI2, MAPK8, MPDZ, PIDD1, SLAIN1, TBC1D23, TRAPPC6B, UBA7 and USP44), and missense mutations include the first reports of variants in BDNF or TET1 associated with ID. The genes identified also showed overlap with de novo gene sets for other neuropsychiatric disorders. Transcriptional studies showed prominent expression in the prenatal brain. The high yield of AR mutations for ID indicated that this approach has excellent clinical potential and should inform clinical diagnostics, including clinical whole exome and genome sequencing, for populations in which consanguinity is common. As with other AR disorders, the relevance will also apply to outbred populations.

Ptchd1 deficiency induces excitatory synaptic and cognitive dysfunctions in mouse.

Synapse development and neuronal activity represent fundamental processes for the establishment of cognitive function. Structural organization as well as signalling pathways from receptor stimulation to gene expression regulation are mediated by synaptic activity and misregulated in neurodevelopmental disorders such as autism spectrum disorder (ASD) and intellectual disability (ID). Deleterious mutations in the PTCHD1 (Patched domain containing 1) gene have been described in male patients with X-linked ID and/or ASD. The structure of PTCHD1 protein is similar to the Patched (PTCH1) receptor; however, the cellular mechanisms and pathways associated with PTCHD1 in the developing brain are poorly determined. Here we show that PTCHD1 displays a C-terminal PDZ-binding motif that binds to the postsynaptic proteins PSD95 and SAP102. We also report that PTCHD1 is unable to rescue the canonical sonic hedgehog (SHH) pathway in cells depleted of PTCH1, suggesting that both proteins are involved in distinct cellular signalling pathways. We find that Ptchd1 deficiency in male mice (Ptchd1-/y) induces global changes in synaptic gene expression, affects the expression of the immediate-early expression genes Egr1 and Npas4 and finally impairs excitatory synaptic structure and neuronal excitatory activity in the hippocampus, leading to cognitive dysfunction, motor disabilities and hyperactivity. Thus our results support that PTCHD1 deficiency induces a neurodevelopmental disorder causing excitatory synaptic dysfunction.

El priapismo en la Leucemia Mieloide Crónica Hallazgos radiológicos en casos de Leucemia Mieloide Crónica que se presentaron con priapismo / 7 PRIAPISM IN CHRONIC MYELOID LEUKEMIA : IMAGING FINDINGS IN CASES OF CHRONIC MYELOID LEUKEMIA WHO PRESENTED WITH PRIAPISM

El priapismo es una emergencia urológica que debe ser diagnosticada y tratada apropiadamente. Específicamente en casos conocidos de leucemia el pene turgente doloroso debe hacer surgir la sospecha de priapismo de primera movida y el Doppler peneano debe ser la mera línea de modalidad de imágenes. Esta información debe ser transmitida al paciente y al departamento clínico emergentológico

Priapism is an urological emergency and must be diagnosed and treated appropriately. Specifically in known cases of leukemia painful turgid penis should raise suspicion of priapism in first hand and penile Doppler should be the first line of imaging modality. This information should be forwarded to patient and emergency department clinician

Orbital foreign body- Study of a case series.

BACKGROUND: Orbital foreign bodies (OFBs) may remain in the orbital cavity for considerable time and manifest with secondary complications. OBJECTIVE: To report five consecutive cases of orbital trauma with OFBs, who presented at our institute from Jan 2010 to Dec 2013. CASES: The first case of our series with a non-specific history of injury had a chronic granulomatous discharging sinus in the left upper eyelid and an intact globe. The second case, with an injury to the left lower eyelid following an assault, presented late and the manifestations were similar to that of the first case. The third case, of a road traffic accident, had sustained multiple facial and periocular injuries. The nature of all of three OFBs was uncertain by CT- scan, till surgical exploration. The fourth case had sustained injury to his left eye by a flying metal object. X-ray was sufficient to detect the OFB, but as scleral penetration was associated, management was complex. The fifth case had a nonspecific history of injury and the manifestation was similar to that of the first case. The surgical exploration revealed multiple OFB (wood). CONCLUSION: The OFBs pose difficult diagnostic and therapeutic challenges. Management of such cases, at times, calls for innovation in decision making and formulation of strategies.

Note: On the generation of sub-300 keV flash-X-rays using rod-pinch diode: an experimental investigation.

Generation of flash X-rays (FXRs) at less than 500 keV is described with emphasis on experimental investigation. The pulser is a Tesla transformer-Water transmission line based pulsed power generator operating in double resonance mode to power a rod-pinch diode. The configuration of aspect ratio reported here falls much below the normally reported ratios for the rod-pinch diode operation. Experimental investigation at such low pulsed voltage has revealed "flowering" of the anode tip and "pitting" of the perspex window. A possible explanation in terms of Lorentz body force is discussed rather than the pinch mechanism generally suggested in literature. The experimental investigation for the FXR generation is corroborated by measuring the radiation dose using CaSO4 (Dy) thermo luminescent dosimeters.

Experimental investigations of argon spark gap recovery times by developing a high voltage double pulse generator.

The voltage recovery in a spark gap for repetitive switching has been a long research interest. A two-pulse technique is used to determine the voltage recovery times of gas spark gap switch with argon gas. First pulse is applied to the spark gap to over-volt the gap and initiate the breakdown and second pulse is used to determine the recovery voltage of the gap. A pulse transformer based double pulse generator capable of generating 40 kV peak pulses with rise time of 300 ns and 1.5 µs FWHM and with a delay of 10 µs-1 s was developed. A matrix transformer topology is used to get fast rise times by reducing L(l)C(d) product in the circuit. Recovery Experiments have been conducted for 2 mm, 3 mm, and 4 mm gap length with 0-2 bars pressure for argon gas. Electrodes of a sparkgap chamber are of rogowsky profile type, made up of stainless steel material, and thickness of 15 mm are used in the recovery study. The variation in the distance and pressure effects the recovery rate of the spark gap. An intermediate plateu is observed in the spark gap recovery curves. Recovery time decreases with increase in pressure and shorter gaps in length are recovering faster than longer gaps.

Note: computational estimation of sparkgap inductance in nitrogen medium.

In this Note, attempt has been made to analytically derive the inductance of a sparkgap arc channel using fundamental circuit theory, heat transfer theory, and gas plasma equations. Simulation of a picosecond phenomenon of arc channel formation is attempted using coupled codes. Arc channel is assumed to be cylindrical and modeled as finite number of small coaxial cylinders filled with gas plasma. Conductivity of each gas plasma cylinder is found by its temperature. Current distribution in the cylinders is calculated using circuit theory and change in the current distribution with time is simulated. Over all inductance of the arc channel is computed for the current density distribution. Simulation is done for fast sub-nanosecond rising pulse. Experiments are conducted to measure the arc channel inductance and validate the same with the value found using computation.

Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source.

A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20-40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, -2 to -4 kV, and 0 kV, respectively. The total ion beam current of 30-40 mA is recorded on Faraday cup at 40 keV of beam energy at 600-1000 W of microwave power, 800-1000 G axial magnetic field and (1.2-3.9) × 10(-3) mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

A 2 weeks on and 1 week off schedule of sunitinib is associated with decreased toxicity in metastatic renal cell carcinoma.

Treatment of metastatic renal cell carcinoma (mRCC) with sunitinib is often associated with toxicity necessitating dose reduction. Maintaining adequate dosing and drug levels are essential for optimising clinical efficacy. Standard sunitinib schedule is 4 weeks of treatment and 2 weeks of rest (schedule 4/2). Empirically, several mRCC patients at The Cleveland Clinic (CCF) have been changed from schedule 4/2 to 2 weeks of treatment/1 week off (schedule 2/1) after experiencing toxicity, in an attempt to maintain daily dosing. The medical records of 30 mRCC patients on sunitinib who were changed from schedule 4/2 to schedule 2/1 at CCF were retrospectively reviewed. Toxicity on each schedule was recorded during routine clinic visits and graded using Common Toxicity Criteria, version 4.0. 97% of patients on schedule 4/2 had grade 3 or 4 toxicity that led to changing to schedule 2/1. There were no grade 4 toxicities on schedule 2/1, and 27% of patients experienced grade 3 toxicity (p=0.0001). Two of the most common toxicities, fatigue and hand-foot syndrome (HFS), were significantly less frequent on schedule 2/1 than on schedule 4/2 (p=0.0003; p=0.0004, respectively). Median overall treatment duration on schedule 4/2 was 12.6 months (range 1.2 months-5.1 years) and median overall treatment duration on schedule 2/1 was 11.9 months (range 0.9+ to 73.3+ months). Treatment with sunitinib on schedule 2/1 is associated with significantly decreased toxicity in patients who experience grade 3 or greater toxicity on schedule 4/2, and can extend treatment duration considerably. Prospective clinical trials are required to define the optimal sunitinib schedule to balance efficacy and toxicity.

Cesarean scar pregnancy and early placenta accreta share common histology.

OBJECTIVE: To determine, by evaluation of histological slides, images and descriptions of early (second-trimester) placenta accreta (EPA) and placental implantation in cases of Cesarean scar pregnancy (CSP), whether these are pathologically indistinguishable and whether they both represent different stages in the disease continuum leading to morbidly adherent placenta in the third trimester. METHODS: The database of a previously published review of CSP and EPA was used to identify articles with histopathological descriptions and electronic images for pathological review. When possible, microscopic slides and/or paraffin blocks were obtained from the original researchers. We also included from our own institutions cases of CSP and EPA for which pathology specimens were available. Two pathologists examined all the material independently and, blinded to each other's findings, provided a pathological diagnosis based on microscopic appearance. Interobserver agreement in diagnosis was determined. RESULTS: Forty articles were identified, which included 31 cases of CSP and 13 cases of EPA containing histopathological descriptions and/or images of the pathology. We additionally included six cases of CSP and eight cases of EPA from our own institutions, giving a total of 58 cases available for histological evaluation (37 CSP and 21 EPA) containing clear definitions of morbidly adherent placenta. In the 29 cases for which images/slides were available for histopathological evaluation, both pathologists attested to the various degrees of myometrial and/or scar tissue invasion by placental villi with scant or no intervening decidua, consistent with the classic definition of morbidly adherent placenta. Based on the reviewed material, cases with a diagnosis of EPA and those with a diagnosis of CSP showed identical histopathological features. Interobserver correlation was high (kappa = 0.93). CONCLUSIONS: EPA and placental implantation in CSP are histopathologically indistinguishable and may represent different stages in the disease continuum leading to morbidly adherent placenta in the third trimester.

Comparison of estimation of volume of fetomaternal hemorrhage using Kleihauer-Betke test and microcolumn gel method in D-negative nonisoimmunized mothers.

In this study we assessed the efficay of the microcolumn gel method in the detection and quantification of the volume of fetomaternal hemorrhage (FMH) in comparison with the Kleihauer-Betke test (KB) in nonisoimmunized D- mothers. We collected blood samples from 80 D- indirect antiglobulin test-negative mothers over a span of more than 1 year. FMH was determined by KB and microcolumn gel method, and the results were compared. FMH was recorded as less than 4 mL by KB if no fetal cells were seen after examining 25 fields using 10x objective. If fetal cells were seen, slides were examined furhter to quantify FMH. By microcolumn gel method, FMH was reported as less than 0.1 percent, 0.1 percent, 0.2 percent, and 0.4 percent or greater. None of the patients had FMH greater than 15 mL by KB . Sixty-two patients (77.5%) had FMH less than 4mL by KB. In all these cases , FMH was less than or equal 0.2 percent (approximately 4mL) by microcolumn gel method. The mean volume of FMH in the remaining 18 (22.5%) cases by KB was 8.3 ± 1.7 mL. Fifteen (83.3%) of these 18 cases had FMH of at least 0.4 percent (approximately 8 mL) by gel technology. Three cases (16.7%) that differed from KB results had FMH of 0.2 percent by microcolumn gel method with a maximal FMH of 6.4 mL by KB. FMH was significanlty increased in cesarean delivery (mean FMH 9.5 ± 0.8 mL, range 7.9-10.4 mL, p=0.001) abd abtepartum hemorrahge (mean FMH 9.5 ± 0.9 mL, range 7.9-10.4 mL, p< 0.001). Microcolumn gel method is an effective screening test . Technologies like KB and flow cytometry are better options for detecting a large volume of FMh. Antepartum hemorrhage and cesarean delivery are risk factors for FMH. the 300-µg dose of cases. We need to analyze the relative cost-effectiveness of universal administration of 300µg of Rh immune globulin vs. FMH quantitation with subsequent administration of titrated doses.

Analysis and development of fourth order LCLC resonant based capacitor charging power supply for pulse power applications.

A fourth order (LCLC) resonant converter based capacitor charging power supply (CCPS) is designed and developed for pulse power applications. Resonant converters are preferred t utilize soft switching techniques such as zero current switching (ZCS) and zero voltage switching (ZVS). An attempt has been made to overcome the disadvantages in 2nd and 3rd resonant converter topologies; hence a fourth order resonant topology is used in this paper for CCPS application. In this paper a novel fourth order LCLC based resonant converter has been explored and mathematical analysis carried out to calculate load independent constant current. This topology provides load independent constant current at switching frequency (fs) equal to resonant frequency (fr). By changing switching condition (on time and dead time) this topology has both soft switching techniques such as ZCS and ZVS for better switching action to improve the converter efficiency. This novel technique has special features such as low peak current through switches, DC blocking for transformer, utilizing transformer leakage inductance as resonant component. A prototype has been developed and tested successfully to charge a 100 µF capacitor to 200 V.

Langmuir probe diagnostics of plasma in high current electron cyclotron resonance proton ion source.

A high current Electron Cyclotron Resonance (ECR) proton ion source has been developed for low energy high intensity proton accelerator at Bhabha Atomic Research Centre. Langmuir probe diagnostics of the plasma generated in this proton ion source is performed using Langmuir probe. The diagnostics of plasma in the ion source is important as it determines beam parameters of the ion source, i.e., beam current, emittance, and available species. The plasma parameter measurement in the ion source is performed in continuously working and pulsed mode using hydrogen as plasma generation gas. The measurement is performed in the ECR zone for operating pressure and microwave power range of 10(-4)-10(-3) mbar and 400-1000 W. An automated Langmuir probe diagnostics unit with data acquisition system is developed to measure these parameters. The diagnostics studies indicate that the plasma density and plasma electron temperature measured are in the range 5.6 × 10(10) cm(-3) to 3.8 × 10(11) cm(-3) and 4-14 eV, respectively. Using this plasma, ion beam current of tens of mA is extracted. The variations of plasma parameters with microwave power, gas pressure, and radial location of the probe have been studied.

Hydrolysis of acid and alkali presoaked lignocellulosic biomass exposed to electron beam irradiation.

In this study, synergetic effect of mild acid and alkali with electron beam irradiation (EBI) on the enzymatic hydrolysis of a selected grass biomass was assessed. Biomass samples prepared by soaking with 1% H2SO4, or 1% NaOH, were exposed to 75 and 150 kGy of EBI. Water presoaked biomass was used as control. Hydrolysis of pretreated samples was carried out using cellulase (15 FPU/g biomass) for 120 h. Structural changes were studied by FTIR and XRD analyses. Reducing sugar and glucose yields from enzymatic hydrolysis were significantly higher in acid and alkali presoaked EBI exposed samples. Theoretical glucose yield showed 40% increase from control in alkali presoaked EBI exposed (150 kGy) samples. Removal of hemicellulose, decreased crystallinity and structural changes were major factors for the combined treatment effect favoring the hydrolysis.