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Ultrasound (US) shear wave (SW) elastography has been widely studied and implemented on clinical systems to assess the elasticity of living organs. Imaging of SW attenuation reflecting viscous properties of tissues has received less attention. A revisited frequency shift (R-FS) method is proposed to improve the robustness of SW attenuation imaging. Performances are compared with the FS method that we originally proposed and with the two-point frequency shift (2P-FS) and attenuation measuring US SW elastography (AMUSE) methods. In the proposed R-FS method, the shape parameter of the gamma distribution fitting SW spectra is assumed to vary with distance, in contrast to FS. Second, an adaptive random sample consensus (A-RANSAC) line fitting method is used to prevent outlier attenuation values in the presence of noise. Validation was made on ten simulated phantoms with two viscosities (0.5 and 2 Pa [Formula: see text]) and different noise levels (15 to -5 dB), two experimental homogeneous gel phantoms, and six in vivo liver acquisitions on awake ducks (including three normal and three fatty duck livers). According to the conducted experiments, R-FS revealed mean reductions in coefficients of variation (CV) of 62.6% on simulations, 62.5% with phantoms, and 62.3% in vivo compared with FS. Corresponding reductions compared with 2P-FS were 45.4%, 77.1%, and 62.0%, respectively. Reductions in normalized root-mean-square errors for simulations were 63.9% and 48.7% with respect to FS and 2P-FS, respectively.

Change in viscoelastic properties of biological tissues may often be symptomatic of dysfunction that can be correlated with tissue pathology. Shear wave (SW) elastography is an imaging method mainly used to assess stiffness but with the potential to measure viscoelasticity of biological tissues. This can enable tissue characterization and, thus, can be used as a marker to improve the diagnosis of pathological lesions. In this study, a frequency-shift method-based framework is presented for the reconstruction of viscosity by analyzing the spectral properties of acoustic radiation force-induced SWs. The aim of this study was to investigate the feasibility of viscosity reconstruction maps in homogeneous as well as heterogeneous samples. Experiments were performed in four in vitro phantoms, two ex vivo porcine liver samples, two ex vivo fatty duck liver samples, and one in vivo fatty goose liver. Successful viscosity maps were reconstructed in homogeneous and heterogeneous phantoms with embedded mechanical inclusions having different geometries. Quantitative values of viscosity obtained for two porcine liver tissues, two fatty duck liver samples, and one goose fatty liver were (mean ± SD) 0.61 ± 0.21 and 0.52 ± 0.35, 1.28 ± 0.54 and 1.36 ± 0.73, and 1.67 ± 0.70 Pa.s, respectively.

Identification of operating system kernel version is essential in a large number of forensic and security applications in both cloud and local environments. Prior state-of-the-art uses complex differential analysis of several aspects of kernel implementation and knowledge of kernel data structures. In this paper, we present a working research prototype codeid-elf for ELF binaries based on its Windows counterpart codeid, which can identify kernels through relocation entries extracted from the binaries. We show that relocation-based signatures are unique and distinct and thus, can be used to accurately determine Linux kernel versions and derandomize the base address of the kernel in memory (when kernel Address Space Layout Randomization is enabled). We evaluate the effectiveness of codeid-elf on a subset of Linux kernels and find that the relocations in kernel code have nearly 100% code coverage and low similarity (uniqueness) across various kernels. Finally, we show that codeid-elf, which leverages relocations in kernel code, can detect all kernel versions in the test set with almost 100% page hit rate and nearly zero false negatives.

INTRODUCTION: Cesarean section is a live saving procedure but when performed without appropriate indications can add risk to both mother and baby. As per WHO report, at population level, Cesarean section rates higher than 10% are not associated with reductions in maternal and new-born mortality rates. In India as per District level household survey 3 (DLHS) Cesarean section rate is 28.1% in private sector and 12% in public sector health care facilities. The close embryonic development and anatomical proximity of the urinary bladder and genital organs, are responsible for the urinary tract to injury during surgical procedures in the female pelvis. During LSCS bladder injury is demonstrated by the presence of gas filling up the Foley bag or visibly bloody urine in the Foley bag. Veress needle injuries and other small injuries to the bladder can be successfully managed conservatively by catheter drainage for seven to 14 days followed by cystography while large bladder injuries, such as from 5 or 10 mm trocar or surgical dissection usually require suturing the injuries closed. Risk factors for bladder injury during LSCS include previous operations, expodure to radiation, malignancy, chronic infection, and inflammation. MATERIAL AND METHODS: In suspected cases of bladder injuries cystogram X-ray of the bladder after injection of contrast medium is performed. For extraperitoneal injuries (grade 2) without complicating factors, treatment is a insertion of Foley catheter for 7 - 14 days. grade 3 to grade 5 injuries generally require operative repair. Closed suction drains should be left in place after repairs. Suprapubic tube placement is not necessary in most cases. For injuries to the ventral bladder, dome, or posterior bladder, the mucosa is closed in a running fashion using 3-0 vicryl followed by a seromuscular running suture of 2-0 vicryl. The bladder is irrigated to ensure a watertight closure. A third layer in a Lembert fashion can be used in cases at high risk for fistula formation or when a leak is identified. In the laparoscopic setting, a one-layer closure is performed using 2-0 vicryl to close all layers of the bladder. An additional layer can then be added using a 2- 0 vicryl in a Lembert fashion for more extensive injuries. RESULTS: There were 986 LSCS done in the department of Obstetrics and gynaecology in the given study period. Of which 14 were diagnosed with the bladder injuries during. Among all patients who suffered from bladder injury, 3 cases were primigravida and 11 were multigravida type. Out of 14injuries, 10 injuries were repaired in 2 layers by vicryl 2.0 without insertion of SPC (suprapubic cystectomy) whereas 4 injuries were repaired by primary repair with vicryl 2.0 with insertion of SPC. In post-operative period patients were monitored for vitals, urine output and stitch sites of wounds. No complications were found in 13 patients post operatively and Foleys catheter and SPC catheter were removed after 12 days of operation in those patients. CONCLUSION: 1.4% of the bladder injuries were observed. Early detection and prompt management of bladder injury can decrease the morbidity and mortality in LSCS cases

INTRODUCTION: Lower Segment Cesarean Section (LSCS) delivery is a major obstetrical surgical procedure to save the lives of mothers and fetus. Various risk factors in SSI following LSCS has been identified which includes subcutaneous hematoma, subcutaneous hematoma, tobacco use in pregnancy, incision length > 16.6 cm , body mass index >30 or 35 kg/m2, prolonged second stage (compared with first stage) , no antibiotic prophylaxis, duration of labor >12 h , premature rupture of membranes , gestational diabetes, previous cesarean delivery and emergency delivery. Diagnosis of surgical site infection requires evidence of clinical signs and symptoms of infection which may be further supported by microbiological evidence. MATERIAL AND METHODS: A total of 646 patients were included in the study of which 27 were diagnosed as SSI. Risk factor for SSI was divided into three categories: 1) host-related factors, 2) pregnancy and intrapartum-related factors, and 3) procedure-related factors. RESULTS: Among 646 cesarean sections, surgical site infection was observed in 27(4.1%) cases while he remaining cases had no surgical site infection. Mean age of cases with surgical site infection was observed to be 14.8 years with sd of 3.9 years where as it was 22.1 years in cases with no surgical site infections and sd of 3.2 years. Average number of stay in hospital is found to be 14.1 and 7.3 days respectively in cases with and without surgical site infections. Antibiotics were given on 17.3 days on average in cases with SSI whereas patients without surgical site infections were on antibiotics for 3.1 days on average. Out of total 27 surgical site infection E-coli was isolated in 11(40.8%) cases followed by 7(25.9%) isolations of staphylococcus aureus. Klebsiella pneumonia and pseudomonas aeruginosa were isolated in 3(11.1%) cases each. Acitenobacter was found in only 1(3.7%) case. 2(7.4%) isolates were not identified in our study. CONCLUSION: To reduce the SSI rates post LSCS, proper assessment of risk factors and their modification is required. Frequent antibiotic susceptibility testing for resistance is required.

Deep vein thrombosis is one of the leading causes of disability and serious illness and can become fatal. The lytic recombinant tissue plasminogen activator (rt-PA) is the main drug used for clot lysis and rapid normalization of venous blood flow. Less than 40% of patients who receive rt-PA treatment have improved blood flow. In this study, we quantitatively monitor the rt-PA treatment in in-vitro blood clots with ultrasound elastography. An acoustic radiation force imaging sequence was implemented on a research ultrasound system to remotely generate shear waves inside the blood clot samples. Porcine blood samples from two different pigs were bought from a local slaughterhouse. Clots of varying viscoelasticity were prepared by allowing different coagulation time between 30 min to 3 days in borosilicate glass pipettes. The clots were then embedded in gelatin-agar phantoms to perform ultrasound measurements. Another batch of clots from the same blood samples was treated with rt-PA drug for 30 min, and ultrasound measurements were performed after treatment. In 11 samples, variations in SW speed before and after rt-PA treatment were not found to be statistically significant (>0.05). However, SW attenuation and clot viscosity declined significantly after rt-PA treatment by 33.49% ± 31.07% (

The limited data photoacoustic image reconstruction problem is typically solved using either weighted or ordinary least squares (LS), with regularization term being added for stability, which account only for data imperfections (noise). Numerical modeling of acoustic wave propagation requires discretization of imaging region and is typically developed based on many assumptions, such as speed of sound being constant in the tissue, making it imperfect. In this work, two variants of total least squares (TLS), namely ordinary TLS and Sparse TLS were developed, which account for model imperfections. The ordinary TLS is implemented in the Lanczos bidiagonalization framework to make it computationally efficient. The Sparse TLS utilizes the total variation penalty to promote recovery of high frequency components in the reconstructed image. The Lanczos truncated TLS (Lanczos T-TLS) and Sparse TLS methods were compared with the recently established state-of-the-art methods, such as Lanczos Tikhonov and Exponential Filtering. The TLS methods exhibited better performance for experimental data as well as in cases where modeling errors were present, such as few acoustic detectors malfunctioning and speed of sound variations. Also, the TLS methods does not require any prior information about the errors present in the model or data, making it attractive for real-time scenarios. NRF (Natl Research Foundation, S’pore) MOE (Min. of Education, S’pore) NMRC (Natl Medical Research Council, S’pore) MOH (Min. of Health, S’pore) Accepted version

The model-based image reconstruction techniques for photoacoustic (PA) tomography require an explicit regularization. An error estimate (η2) minimization-based approach was proposed and developed for the determination of a regularization parameter for PA imaging. The regularization was used within Lanczos bidiagonalization framework, which provides the advantage of dimensionality reduction for a large system of equations. It was shown that the proposed method is computationally faster than the state-of-the-art techniques and provides similar performance in terms of quantitative accuracy in reconstructed images. It was also shown that the error estimate (η2) can also be utilized in determining a suitable regularization parameter for other popular techniques such as Tikhonov, exponential, and nonsmooth (l1 and total variation norm based) regularization methods.

The attenuation of near-infrared (NIR) light intensity as it propagates in a turbid medium like biological tissue is described by modified the Beer–Lambert law (MBLL). The MBLL is generally used to quantify the changes in tissue chromophore concentrations for NIR spectroscopic data analysis. Even though MBLL is effective in terms of providing qualitative comparison, it suffers from its applicability across tissue types and tissue dimensions. In this work, we introduce Lambert-W function-based modeling for light propagation in biological tissues, which is a generalized version of the Beer–Lambert model. The proposed modeling provides parametrization of tissue properties, which includes two attenuation coefficients μ0 and η. We validated our model against the Monte Carlo simulation, which is the gold standard for modeling NIR light propagation in biological tissue. We included numerous human and animal tissues to validate the proposed empirical model, including an inhomogeneous adult human head model. The proposed model, which has a closed form (analytical), is first of its kind in providing accurate modeling of NIR light propagation in biological tissues.

Undersea deposition of unexploded ordnance (UXO) constitutes a potential source of contamination of marine environments by hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). Using sediment from a coastal UXO field, Oahu Island, Hawaii, we isolated four novel aerobic RDX-degrading fungi HAW-OCF1, HAW-OCF2, HAW-OCF3 and HAW-OCF5, tentatively identified as members of Rhodotorula, Bullera, Acremonium and Penicillium, respectively. The four isolates mineralized 15-34% of RDX in 58 days as determined by liberated 14CO2. Subsequently we selected Acremonium to determine biotransformation pathway(s) of RDX in more details. When RDX (100 microM) was incubated with resting cells of Acremonium we detected methylenedinitramine (MEDINA), N2O and HCHO. Also we detected hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) together with trace amounts of hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX). Under the same conditions MNX produced N2O and HCHO together with trace amounts of DNX and TNX, but we were unable to detect MEDINA. TNX did not degrade with Acremonium. These experimental findings suggested that RDX degraded via at least two major initial routes; one route involved direct ring cleavage to MEDINA and another involved reduction to MNX prior to ring cleavage. Nitrite was only detected in trace amounts suggesting that degradation via initial denitration did take place but not significantly. Aerobic incubation of Acremonium in sediment contaminated with RDX led to enhanced removal of the nitramine.

Undersea deposition of unexploded ordnance (UXO) constitutes a potential source of contamination of marine environments by hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). The goal of the present study was to determine microbial degradation of RDX and HMX in a tropical marine sediment sampled from a coastal UXO field in the region of Oahu Island in Hawaii. Sediment mixed cultures growing in marine broth 2216 (21 degrees C) anaerobically mineralized 69% or 57% (CO2, 25 days) of the total carbon of [UL-14 C]-RDX (100 microM) or [UL-14 C]-HMX (10 microM), respectively. As detected by PCR-DGGE, members of gamma-proteobacteria (Halomonas), sulfate-reducing delta-proteobacteria (Desulfovibrio), firmicutes (Clostridium), and fusobacterium appeared to be dominant in RDX-enrichment and/or HMX-enrichment cultures. Among 22 sediment bacterial isolates screened for RDX and HMX biodegradation activity under anaerobic conditions, 5 were positive for RDX and identified as Halomonas (HAW-OC4), Marinobacter (HAW-OC1), Pseudoalteromonas (HAW-OC2 and OC5) and Bacillus (HAW-OC6) by their 16S rRNA genes. Sediment bacteria degraded RDX to N2O and HCHO via the intermediary formation of hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and methylenedinitramine. The present findings demonstrate that cyclic nitramine contaminants are likely to be degraded upon release from UXO into tropical marine sediment.

Obstetric anesthesia is demanding but gratifying subspeciality of anesthesiologist. Anesthetic care of pregnant patient is unique in that two patients are cared for simultaneously; the parturient and the foetus. This study was conducted on 50 parturient of ASA I and ASA II, planed for caesarean section. They were randomly divided into two groups of 25 patients each: Group-A (control) 1.8cc bupivacaine 0.5% + 0.5 cc normal saline. Total 2.3cc and Group-B (study) 1.8cc bupivacaine 0.5% +25 mg ketamine 0.5 cc (preservative free) Total 2.3 cc. We summarized that intrathecal 0.5% bupivacaine with preservative free intrathecal ketamine have rapid onset of sensory block, have better hemodynamic stability and have post operative analgesia without affecting neonate. Thus it is safe modality for the parturient undergoing caesarean section, but central side effects like delirium, nystagmus and sedation can occur in some patients.

Intervention research for prevention of occupational low back injuries has focused on the effects of reducing extreme torso flexion and the external moment. Little is known about prevention strategies for torso twisting and lateral bending. The objective of this study was to assess the effect of pallet distance with regard to a constant lift origin on the torso kinematics and a measure of low back disorder risk. Fifteen male participants transferred 11.3 kg boxes from a constant origin to six different regions on a pallet. Two pallet distances with regard to the lift origin were investigated. ANOVA indicated that increasing the pallet distance resulted in increases in torso kinematics (velocities and accelerations) as well as a measure of risk of low back disorder. The increases in torso kinematics (e.g. twisting and lateral awkward postures and bending velocities) occurred mostly at the lower height regions on the pallet. It is concluded that increasing the pallet distance with regard to the lifting origin, with the intention to influence the participant to take a step during a palletizing task does not appear to be an effective intervention strategy to reduce the risk of low back disorder associated with torso kinematics.

In previous studies, we found that the emerging energetic chemical, CL-20 (C6H6N12O12, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane), can be degraded following its initial denitration using both aerobic and anaerobic bacteria. The C and N mass balances were not determined due to the absence of labeled starting compounds. The present study describes the degradation of the emerging contaminant by Phanerochaete chrysosporium using ring-labeled [15N]-CL-20 and [14C]-CL-20. Ligninolytic cultures degraded CL-20 with the release of nitrous oxide (N2O) in amounts corresponding to 45% of the nitrogen content of CL-20. When ring-labeled [15N]-CL-20 was used, both 14N14NO and 15N14NO were observed, likely produced from -NO2 and N-NO2, respectively. The incubation of uniformly labeled [14C]-CL-20 with fungi led to the production of 14CO2 (>80%). Another ligninolytic fungus, Irpex lacteus, was also able to degrade CL-20, but as for P. chrysosporium, no early intermediates were observed. When CL-20 was incubated with manganese peroxidase (MnP), we detected an intermediate with a [M-H]- mass ion at 345 Da (or 351 and 349 Da when using ring-labeled and nitro-labeled [15N]-CL-20, respectively) matching a molecular formula of C6H6N10O8. The intermediate was thus tentatively identified as a doubly denitrated CL-20 product. The concomitant release of nitrite ions (Click to view the MathML source) with CL-20 degradation by MnP also supported the occurrence of an initial denitration prior to cleavage and decomposition.Keywords: CL-20; Degradation; Nitramine; Phanerochaete chrysosporium; Fungi

The piezo-phototronic effect is of immense importance for improving the performance of optoelectronic nanodevices. This is accomplished by tuning the charge carrier generation, separation, and transport under the influence of the inner piezopotential. In this paper, a broad band photodetector is demonstrated that is based on II-VI binary CdSe/ZnTe core/shell nanowire arrays, in which photodetection is greatly enhanced by the piezo-phototronic effect. The photodetector performance under UV (385 nm), blue (465 nm), and green (520 nm) illumination infers a saturation free response with an intensity variation near two orders of magnitude, where the peak photocurrent (125 μA) is two orders higher at 0.25 kilogram force (kgf) compared to no load (0.71 μA). The resulting (%) responsivity changed by four orders of magnitude. The significant increase in responsivity is believed to arise from: 1) the piezo-phototronic effect induced by a change in the Schottky barrier height at the Ag–ZnTe junction, and in the type-II band alignment at the CdSe–ZnTe interfaces, in conjugation with 2) a small lattice mismatch between the CdSe and ZnTe epitaxial layers, which lead to reduced charge carrier recombination. This work thus extends the piezo-phototronic effect to a group II-VI binary semiconductor heterostructure and demonstrates the importance of the epitaxial interface in a core/shell nanowire photodetector.

We report a case of an isolated hydatid cyst of the kidney, associated with loss of renal function; such a case has not been reported to the best of our knowledge. We performed a transperitoneal simple nephrectomy under general anesthesia after cyst aspiration and injection of scolicidal solution, followed by pericystectomy. In general, kidney-sparing surgery is the most appropriate treatment whenever possible, however in rare cases associated with loss of renal function nephrectomy is performed.