Deformed graphene FET biosensor on textured glass coupled with dielectrophoretic trapping for ultrasensitive detection of GFAP.

Numerous efforts have been undertaken to mitigate the Debye screening effect of FET biosensors for achieving higher sensitivity. There are few reports that show sub-femtomolar detection of biomolecules by FET mechanisms but they either suffer from significant background noise or lack robust control. In this aspect, deformed/crumpled graphene has been recently deployed by other researchers for various biomolecule detection like DNA, COVID-19 spike proteins and immunity markers like IL-6 at sub-femtomolar levels. However, the chemical vapor deposition (CVD) approach for graphene fabrication suffers from various surface contamination while the transfer process induces structural defects. In this paper, an alternative fabrication methodology has been proposed where glass substrate has been initially texturized by wet chemical etching through the sacrificial layer of synthesized silver nanoparticles, obtained by annealing of thin silver films leading to solid state dewetting. Graphene has been subsequently deposited by thermal reduction technique from graphene oxide solution. The resulting deformed graphene structure exhibits higher sensor response towards glial fibrillary acidic protein (GFAP) detection with respect to flat graphene owing to the combined effect of reduced Debye screening and higher surface area for receptor immobilization. Additionally, another interesting aspect of the reported work lies in the biomolecule capture by dielectrophoretic (DEP) transport on the crests of the convex surfaces of graphene in a coplanar gated topology structure which has resulted in 10 aM and 28 aM detection limits of GFAP in buffer and undiluted plasma respectively, within 15 min of application of analyte. The detection limit in buffer is almost four decades lower than that documented for GFAP using biosensors which is is expected to pave way for advancing graphene FET based sensors towards ultrasensitive point-of-care diagnosis of GFAP, a biomarker for traumatic brain injury.

Measurement of energy and directional distribution of neutron ambient dose equivalent for the 7Li(p,n)7Be reaction.

Double differential neutron fluence distributions were measured in the 7Li(p,n)7Be reaction for proton beam energies 7, 9 and 12 MeV. Seven liquid scintillator based detectors were employed to measure neutron fluence distributions using the Time of Flight technique. Neutron ambient dose equivalents were determined from the measured fluence distribution using ICRP (International Commission on Radiological Protection) recommended fluence to dose equivalent conversion coefficients. Neutron dose equivalents were also measured using a conventional BF3 detector based REM counter. Ambient dose equivalent measured by the REM counter is found to be in agreement with that determined from the neutron fluence spectra within their uncertainties. Angular distributions of the ambient dose equivalents were also determined from the measured fluence distributions at different angles.

Next generation high resolution perovskite direct conversion detector: Monte Carlo design optimisation and virtual clinical trial.

We implement virtual clinical integration of next-generation perovskite detectors into common x-ray imaging devices. This was achieved by performing Monte Carlo (MC) optimisation of the design and benchmarking of low cost, high spatial resolution, direct conversion perovskite crystal x-ray flat panel imagers for a next generation of breast-, MV-, and kV-cone beam CT detectors. Semiconductor methylammonium lead bromide perovskite crystals energy deposition efficiencies calculated in TOPAS were benchmarked against four common detector materials for twelve detector crystal thicknesses between 40 to 15 mm and ten beam energies ranging from 20 keV to 6 MeV. Based on these simulations, Koning's dedicated breast CT, and Varian's Truebeam kV- and MV-cone beam CT systems were designated as suitable applications for perovskite detectors. System specific Fastcat hybrid MC cone beam CT image simulation was subsequently used to optimise the perovskite detector design and conduct virtual clinical trials. Device-specific optimal perovskite crystal thicknesses were calculated to be 0.30, 0.86, and 1.99 mm for Koning breast CT and Truebeam kV- and MV-cone beam CT systems, respectively. Replacing the current detectors on these machines with low cost perovskite crystal detectors could be advantageous as it would simultaneously yield 12.1%, 9.5% and 86.1% improvements in detective quantum efficiency as well as increases in contrast to noise ratio in brain, lung, and bone tissues.

Safety and Feasibility of Trans Radial Percutaneous Coronary Intervention Approach in Elderly Patients with Acute Coronary Syndrome.

Coronary catheterization is usually performed using the transfemoral approach but trans-radial has been increasingly used as an alternative to transfemoral approach due to less vascular complications, earlier ambulation time and improved patient comfort. The aim of the study was to compare the safety and feasibility of trans-radial and transfemoral PCI in the elderly ACS patients. This prospective observational study was conducted in the NICVD, Dhaka from October 2017 to September 2018. Total 80 patients were categorized into two groups according to the approach of PCI. Group I consists 40 patients who underwent trans-radial PCI and Group II consists 40 patients who underwent transfemoral PCI. Patients with abnormal Allen's test, history of CABG, CKD were excluded. Patient's demographics were same in both groups. The mean procedural time in min (37.44±5.13 vs. 34.42±4.42, p=0.004) and fluoroscopy time in min (21.6±4.11 vs. 17.55±2.78, p=0.02) were more in Group I but the mean hemostasis time in min (7.58±1.11 vs. 15.59±3.33, p=0.005) and the ambulation time in hour (0.00±0.00 vs. 15.59±3.33, p=0.001) were more in Group II. Significant arterial spasm following puncture (10.0% vs. 0.0%, p=0.01) were more in Group I. Post procedural major bleeding (0.0% vs. 10.0%, p=0.004), minor bleeding (10.0% vs. 20.0%, p=0.004) were significant in Group II but vessel occlusion (5.0% vs. 0.0%, p=0.02) were significant in Group I. Transradial PCI is safe in respect of procedural and post procedural vascular complications. Transradial procedure leads to improved quality of life after the procedure and thus gives much comfort to the patient. It also shortened mean duration of hospital stay. So transradial approach is an attractive alternative to conventional transfemoral approach in the elderly.

The Tumor Microenvironment: An Introduction to the Development of Microfluidic Devices.

The tumor microenvironment (TME) is like the Referee of a soccer match who has constant eyes on the activity of all players, such as cells, acellular stroma components, and signaling molecules for the successful completion of the game, that is, tumorigenesis. The cooperation among all the "team members" determines the characteristics of tumor, such as the hypoxic and acidic niche, stiffer mechanical properties, or dilated vasculature. Like in soccer, each TME is different. This heterogeneity makes it challenging to fully understand the intratumor dynamics, particularly among different tumor subpopulations and their role in therapeutic response or resistance. Further, during metastasis, tumor cells can disseminate to a secondary organ, a critical event responsible for approximately 90% of the deaths in cancer patients. The recapitulation of the rapidly changing TME in the laboratory is crucial to improve patients' prognosis for unraveling key mechanisms of tumorigenesis and developing better drugs. Hence, in this chapter, we provide an overview of the characteristic features of the TME and how to model them, followed by a brief description of the limitations of existing in vitro platforms. Finally, various attempts at simulating the TME using microfluidic platforms are highlighted. The chapter ends with the concerns that need to be addressed for designing more realistic and predictive tumor-on-a-chip platforms.

Impact of Myocardial Blush Grade on In-Hospital Outcome after Primary Percutaneous Coronary Intervention.

Primary percutaneous coronary intervention (PPCI) is the optimal reperfusion strategy in patients with ST elevation Myocardial Infarction (STEMI). However, despite achieving TIMI 3 flow after PPCI, some patients have less optimal perfusion at the myocardial tissue level, as assessed by Myocardial Blush Grade (MBG) and consequently show adverse outcome. This prospective observational study was performed in the National Institute of Cardiovascular Diseases (NICVD), Dhaka, Bangladesh from March 2016 to February 2017. Total 74 patients with STEMI who underwent primary PCI and achieved TIMI 3 flow were included among them 37 patients were taken with low MBG (grade 0 or 1) in Group I and other 37 patients with high MBG (grade II or III) were taken in Group II. Mean age of Group I and Group II were 53.70±9.17 and 51.49±9.41 years respectively (p=0.536). Male to female ratio was 5.7:1. Smoking (59.5% versus 35.1%, p=0.036) and diabetes mellitus (43.2% versus 18.9%, p=0.024) were significantly higher in low MBG group than high MBG group. Multi vessel involvement (24.3% versus 5.4%, p=0.022) and anterior MI (72.9% versus 51.4%, p=0.047) were significantly higher in low MBG group. LVEF was significantly lower in low MBG group than high MBG group (49.92?6.60% versus 58.84?4.55%, p=0.003). Among the complications acute heart failure was found significantly higher in low MBG group than high MBG group (8.1% versus 0.0%, p=0.048) along with total adverse in hospital outcome (24.3% versus 5.4%, p=0.041). In study population total mortality was 2.7% and all were in low MBG group (5.4%). Multivariate logistic regression analysis showed MBG was an independent predictor of adverse in hospital outcome after PPCI (OR 6.553, 95% CI 1.984-21.643, p=0.002). Low MBG is associated with more adverse in hospital outcome after PPCI. So, along with TIMI 3 flow following PPCI we have to assess MBG for evaluation of complete reperfusion and further outcome.

Ultrasound characteristics, serum biochemistry and outcome of ectopic pregnancies presenting during COVID-19 pandemic.

OBJECTIVE: To describe and compare the characteristics of ectopic pregnancies (EPs) in the year prior to vs during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: This was a retrospective analysis of women diagnosed with an EP on transvaginal sonography conducted at a center in London, UK, providing early-pregnancy assessment, between 1 January 2019 and 31 December 2020. Women were identified via the Astraia ultrasound reporting system using coded and non-coded outcomes of EP or pregnancy outside the uterine cavity. Data related to predefined outcomes were collected using Astraia and Cerner electronic reporting systems. Main outcome measures included clinical, ultrasound and biochemical features of EP, in addition to reported complications and management. RESULTS: There were 22 683 consultations over the 2-year period. Following consultation, a similar number and proportion of EPs were diagnosed in 2019 (141/12 657 (1%)) and 2020 (134/10 026 (1%)). Both cohorts were comparable in age, ethnicity, weight and method of conception. Gestational age at the first transvaginal sonography scan and at diagnosis were similar, and no difference in location, size or morphology of EP was found between the two cohorts. Serum human chorionic gonadotropin (hCG) levels at the time of EP diagnosis were higher in 2020 than in 2019 (1005 IU/L vs 665 IU/L; P = 0.03). The proportions of women according to type of final EP management were similar, but the rate of failed first-line management was higher during vs before the pandemic (16% vs 6%; P = 0.01). The rates of blood detected in the pelvis (hemoperitoneum) on ultrasound (23% vs 26%; P = 0.58) and of ruptured EP confirmed surgically (9% vs 3%; P = 0.07) were similar in 2019 vs 2020. CONCLUSIONS: No difference was observed in the location, size, morphology or gestational age at the first ultrasound examination or at diagnosis of EP between women diagnosed before vs during the COVID-19 pandemic. Complication rates and final management strategy were also unchanged. However, hCG levels and the failure rate of first-line conservative management measures were higher during the pandemic. Our findings suggest that women continued to access appropriate care for EP during the COVID-19 pandemic, with no evidence of diagnostic delay or an increase in adverse outcome in our population. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Modulation of inflammation by anti-TNF α mAb-dendrimer nanoparticles loaded in tyramine-modified gellan gum hydrogels in a cartilage-on-a-chip model.

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by joint inflammation. Since the inflammatory condition plays an important role in the disease process, it is important to develop and test new therapeutic approaches that specifically target and treat joint inflammation. In this study, a human 3D inflammatory cartilage-on-a-chip model was established to test the therapeutic efficacy of anti-TNFα mAb-CS/PAMAM dendrimer NPs loaded-Tyramine-Gellan Gum in the treatment of inflammation. The results showed that the proposed therapeutic approach applied to the human monocyte cell line (THP-1) and human chondrogenic primary cells (hCH) cell-based inflammation system revealed an anti-inflammatory capacity that increased over 14 days. It was also possible to observe that Coll type II was highly expressed by inflamed hCH upon the culture with anti-TNF α mAb-CS/PAMAM dendrimer NPs, indicating that the hCH cells were able maintain their biological function. The developed preclinical model allowed us to provide more robust data on the potential therapeutic effect of anti-TNF α mAb-CS/PAMAM dendrimer NPs loaded-Ty-GG hydrogel in a physiologically relevant model.

Inhibition of growth and virulence of Vibrio cholerae by carvacrol, an essential oil component of Origanum spp.

AIMS: In the age where bacterial resistance to conventional antibiotics is increasing at an alarming rate, the use of the traditional plant, herb extracts or other bioactive constituents is gradually becoming popular as an anti-virulence agent to treat pathogenic diseases. Carvacrol, a major essential oil fraction of Oregano, possesses a wide range of bioactivities. Therefore, we aimed to study the effect of sub-inhibitory concentrations of carvacrol on major virulence traits of Vibrio cholerae. METHODS AND RESULTS: We have used in vitro as well as ex vivo models to access the anti-pathogenic role of carvacrol. We found that the sub-inhibitory concentration of carvacrol significantly repressed bacterial mucin penetrating ability. Carvacrol also reduced the adherence and fluid accumulation in the rabbit ileal loop model. Reduction in virulence is associated with the downregulated expression of tcpA, ctxB, hlyA and toxT. Furthermore, carvacrol inhibits flagellar synthesis by downregulating the expression of flrC and most of the class III genes. CONCLUSIONS: Carvacrol exhibited anti-virulence activity against V. cholerae, which involved many events including the inhibition of mucin penetration, adhesion, reduced expression of virulence-associated genes culminating in reduced fluid accumulation. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings indicate that carvacrol possesses inhibitory activity against V. cholerae pathogenesis and might be considered as a potential bio-active therapeutic alternative to combat cholera.

Effect of surfactant on quality and performance attributes of topical semisolids.

Surfactants are the most common inactive ingredients used in topical drug products. Surfactants in topical products play many functional roles such as emulsifiers, permeation enhancers, and solubilizers. This study was aimed to evaluate the influence of incremental change in the concentration of a surfactant (tween 80) on the quality attributes and performance of semisolid topical products. Four creams were prepared using metronidazole as a model drug using the same manufacturing protocol and similar composition except for the concentration of tween 80, which was increased by 5% w/w across SF1 to SF4. The quality attributes like globule size, pH, drying rate, and in-vitro permeation profile were characterized. The critical quality attributes did not differ significantly across the products. However, there was a significant difference in the permeation profile of the products. The permeation flux (Jmax) varied from SF1 to SF4 (51.25 ± 35.29 to 307.98 ± 138.89 ng/cm2/h, respectively). The reason for the difference in the performance of products despite having consistent quality attributes was investigated. One of the major reasons was found to be the difference in the time course of degree of saturation of drug during the evaporative metamorphosis. This study confirms that the time course of degree of saturation is one of the important quality attributes of the topical product that could influence bioavailability and performance of topical products.

Electron Spin-Polarization Dependent Damage to Chiral Amino Acid l-Histidine.

The damage of approximately monolayer films of l-histidine by low-energy spin-polarized electrons (SPE) ejected from a magnetized cobalt substrate has been probed using X-ray photoelectron spectroscopy (XPS). Average damage cross sections for N-containing motifs of l-histidine are 25-30 and 2-5 Mb for zwitterions and neutral molecules, respectively. The magnetization direction of the substrate, which controls the ejected SPE helicity, was reversed in situ, and statistically significant differences in the damage cross sections of 10-30% were measured between positive and negative electron helicities. This is the first measurement of spin dichroism (SD) in an amino acid. The differential cross sections suggest that inelastic scattering of SPE with chiral molecules could contribute to the persistence of one enantiomer vs the other under certain irradiation conditions, particularly for the zwitterionic species.

Signatures of a Spin-1/2 Cooperative Paramagnet in the Diluted Triangular Lattice of Y_{2}CuTiO_{6}.

We present a combination of thermodynamic and dynamic experimental signatures of a disorder driven dynamic cooperative paramagnet in a 50% site diluted triangular lattice spin-1/2 system: Y_{2}CuTiO_{6}. Magnetic ordering and spin freezing are absent down to 50 mK, far below the Curie-Weiss scale (-θ_{CW}) of ∼134 K. We observe scaling collapses of the magnetic field and temperature dependent magnetic heat capacity and magnetization data, respectively, in conformity with expectations from the random singlet physics. Our experiments establish the suppression of any freezing scale, if at all present, by more than 3 orders of magnitude, opening a plethora of interesting possibilities such as disorder stabilized long range quantum entangled ground states.

Gapless Quantum Spin Liquid in the Triangular System Sr_{3}CuSb_{2}O_{9}.

We report gapless quantum spin liquid behavior in the layered triangular Sr_{3}CuSb_{2}O_{9} system. X-ray diffraction shows superlattice reflections associated with atomic site ordering into triangular Cu planes well separated by Sb planes. Muon spin relaxation measurements show that the S=1/2 moments at the magnetically active Cu sites remain dynamic down to 65 mK in spite of a large antiferromagnetic exchange scale evidenced by a large Curie-Weiss temperature θ_{CW}≃-143 K as extracted from the bulk susceptibility. Specific heat measurements also show no sign of long-range order down to 0.35 K. The magnetic specific heat (C_{m}) below 5 K reveals a C_{m}=γT+αT^{2} behavior. The significant T^{2} contribution to the magnetic specific heat invites a phenomenology in terms of the so-called Dirac spinon excitations with a linear dispersion. From the low-T specific heat data, we estimate the dominant exchange scale to be ∼36 K using a Dirac spin liquid ansatz which is not far from the values inferred from microscopic density functional theory calculations (∼45 K) as well as high-temperature susceptibility analysis (∼70 K). The linear specific heat coefficient is about 18 mJ/mol K^{2} which is somewhat larger than for typical Fermi liquids.

Effect of different fat and protein levels in calf ration on performance of Sahiwal calves.

OBJECTIVE: The current study was carried out to examine the response of different levels of fat and protein in calf starter on nutrient utilisation, nitrogen metabolism, weight gain, blood parameters and immunity level in pre-ruminant calves. METHODS: Twenty four calves (5 days old) were divided into six groups in a 2x3 factorial design, with two levels of fat (10% and 14 %) and three levels of protein (18%, 21% and 24%). The calves were kept in individual pens for 120 days and fed with whole milk (1/10th of body weight) and calf starter ad-libitum. Daily dry matter intake (DMI) was recorded; whereas body weight was taken on fortnightly basis to calculate average daily gain (ADG). During the growth trial blood samples were collected at 30 days interval to estimate blood glucose, albumin, total protein, total leucocyte count, total immunoglobulin and IgG levels. A metabolic trial of seven days was carried out to find out the digestibility of different nutrients. RESULTS: The DMI was reduced (p<0.05) with higher fat and protein levels whereas feed conversion efficiency (FCE) was improved (p<0.05) with higher protein level. Different levels of fat and protein in calf ration did not affect average daily gain in calves.The dry matter (DM), organic matter (OM) and crude protein (CP) digestibility were significantly (p<0.01) higher with increased level of protein. The nitrogen retention was also significantly higher (p<0.05) at 24 % protein level, similarly the total immunoglobulin was significantly (p< 0.05) high in higher protein fed groups, showed better immunity. CONCLUSION: The present finding suggested that 10 % fat and 18 % protein level of calf starter could be used in Sahiwal calves for optimum performance in terms of weight gain and immunity.

LiZn2V3O8: a new geometrically frustrated cluster spin-glass.

We have investigated the structural and magnetic properties of a new cubic spinel LiZn2V3O8 (LZVO) through x-ray diffraction, dc and ac susceptibility, magnetic relaxation, aging, memory effect, heat capacity and 7Li nuclear magnetic resonance (NMR) measurements. A Curie-Weiss fit of the dc susceptibility [Formula: see text]([Formula: see text]) yields a Curie-Weiss temperature [Formula: see text] K. This suggests strong antiferromagnetic (AFM) interactions among the magnetic vanadium ions. The dc and ac susceptibility data indicate the spin-glass behavior below a freezing temperature T f  [Formula: see text] 3 K. The frequency dependence of the T f  is characterized by the Vogel-Fulcher law and critical dynamic scaling behavior or power law. From both fitting, we obtained the value of the characteristic angular frequency [Formula: see text] [Formula: see text] 3.56 [Formula: see text] 106 Hz, the dynamic exponent [Formula: see text] [Formula: see text] 2.65, and the critical time constant [Formula: see text] [Formula: see text] 1.82 [Formula: see text] 10-6 s, which falls in the conventional range for typical cluster spin-glass (CSG) systems. The value of relative shift in freezing temperature [Formula: see text] [Formula: see text] 0.039 supports a CSG ground states. We also found aging phenomena and memory effects in LZVO. The asymmetric response of the magnetic relaxation below T f  supports the hierarchical model. Heat capacity data show no long-range or short-range ordering down to 2 K. Only about 25% magnetic entropy change [Formula: see text] signifies the presence of strong frustration in the system. The 7Li NMR spectra show a shift and broadening with decreasing temperature. The spin-lattice and spin-spin relaxation rates show anomalies due to spin freezing around 3 K as the bulk magnetization.

Silk fibroin promotes mineralization of gellan gum hydrogels.

Mineralization is a natural process leading to the formation of mineralized tissue such as bone. The chief mineral component of bone is hydroxyapatite (HAp), which is deposited using an organic template like fibrillar Collagen I under physiological condition. Fibrous silk fibroin is structurally homologous to collagen and acts as nucleation site for HAp mineralization when immersed in simulated body fluid (SBF) or fetal bovine serum (FBS), therefore, considered as popular bone regeneration biomaterial. Hence, the mineralization behavior of silk fibroin self-assembled gellan gum enriched 3D hydrogels is investigated under conditions closer to physiological ones using SBF as well as FBS, and also in presence of cells (e.g. human adipose tissue-derived stem cells, ASCs). Incorporation of silk fibroin induces the mineralization in acellular spongy-like hydrogels in composition dependent manner, confirmed by SEM-EDS analysis. In contrast, ASCs mediated mineralization is found in all hydrogel compositions of 3 weeks post-culture under osteogenic conditions as demonstrated by gene expression profile and Alizarin Red S staining. This is perhaps due to the co-existence of fibroin and FBS together induce cell-mediated mineralization. The blending of fibroin offers cheap alternative strategy to improve or guide the repair of mineralized tissue using gellan gum-based biomaterials.

Serum Albumin Level and In-Hospital Outcome of Patients with First Attack Acute Myocardial Infarction.

Acute myocardial infarction (AMI) patients constitute a large proportion of admissions in coronary care unit and their management and risk stratification is of immense importance. A decrease in serum albumin concentration might be associated with an increased risk in the incident of both cardiovascular diseases and worse hospital outcome. We assessed whether serum albumin levels at admission was associated with in-hospital adverse outcome in patients with first attack of acute myocardial infarction (AMI). The aim of the study was to evaluate association of serum albumin level with in-hospital outcome in patients with first attack of acute myocardial infarction. This cross-sectional analytical study was conducted in the department of cardiology in Mymensingh Medical College Hospital, Mymensingh, Bangladesh from March 2017 to February 2018. Total 374 patients of first attack of acute myocardial infarction included considering inclusion and exclusion criteria. The sample population was divided into two groups: Group I (Patients with acute myocardial infarction with serum albumin <3.5gm/dl) and. Group II (Patients with acute myocardial infarction with serum albumin ≥3.5gm/dl). Serum albumin level was measured within 24 hours of admission and the incidence of in-hospital major cardiac outcomes was observed. In this study mean±SD serum albumin level of Group I, Group II were 3.02±0.12gm/dl, 4.48±0.50gm/dl respectively. In Group I patient, 52(59.80%), 7(8.00%), 10(11.50%), developed heart failure, cardiogenic shock, arrhythmias respectively and 8(9.20%) died and in Group II patient 20(7.90%), 7(2.80%), 8(3.20%) developed heart failure, cardiogenic shock, arrhythmias respectively and 4(1.60%) died out of them and all of these outcome were statistically significant. Mean±SD duration of hospital stay of the study population according serum albumin level, in Group I, 5.76±1.83 days, in Group II, 4.40±1.22 days which was statistically significant (p<0.05). In conclusion, patient with first attack of acute myocardial infarction serum albumin level below 3.50gm/dl increased the risk of worse in-hospital outcome.

Low energy secondary electron induced damage of condensed nucleotides.

Radiation damage and stimulated desorption of nucleotides 2'-deoxyadenosine 5'-monophosphate (dAMP), adenosine 5'-monophosphate (rAMP), 2'-deoxycytidine 5'-monophosphate (dCMP), and cytidine 5'-monophosphate (rCMP) deposited on Au have been measured using x-rays as both the probe and source of low energy secondary electrons. The fluence dependent behavior of the O-1s, C-1s, and N-1s photoelectron transitions was analyzed to obtain phosphate, sugar, and nucleobase damage cross sections. Although x-ray induced reactions in nucleotides involve both direct ionization and excitation, the observed bonding changes were likely dominated by the inelastic energy-loss channels associated with secondary electron capture and transient negative ion decay. Growth of the integrated peak area for the O-1s component at 531.3 eV, corresponding to cleavage of the C-O-P phosphodiester bond, yielded effective damage cross sections of about 23 Mb and 32 Mb (1 Mb = 10-18 cm2) for AMP and CMP molecules, respectively. The cross sections for sugar damage, as determined from the decay of the C-1s component at 286.4 eV and the glycosidic carbon at 289.0 eV, were slightly lower (about 20 Mb) and statistically similar for the r- and d- forms of the nucleotides. The C-1s component at 287.6 eV, corresponding to carbons in the nucleobase ring, showed a small initial increase and then decayed slowly, yielding a low damage cross section (∼5 Mb). Although there is no statistical difference between the sugar forms, changing the nucleobase from adenine to cytidine has a slight effect on the damage cross section, possibly due to differing electron capture and transfer probabilities.

Assessing Postconcussive Reaction Time Using Transport-Based Morphometry of Diffusion Tensor Images.

BACKGROUND AND PURPOSE: Cognitive deficits are among the most commonly reported post-concussive symptoms, yet the underlying microstructural injury is poorly understood. Our aim was to discover white matter injury underlying reaction time in mild traumatic brain injury DTI by applying transport-based morphometry. MATERIALS AND METHODS: In this retrospective study, we performed DTI on 64 postconcussive patients (10-28 years of age; 69% male, 31% female) between January 2006 and March 2013. We measured the reaction time percentile by using Immediate Post-Concussion Assessment and Cognitive Testing. Using the 3D transport-based morphometry technique we developed, we mined fractional anisotropy maps to extract the common microstructural injury associated with reaction time percentile in an automated manner. Permutation testing established statistical significance of the extracted injuries. We visualized the physical substrate responsible for reaction time through inverse transport-based morphometry transformation. RESULTS: The direction in the transport space most correlated with reaction time was significant after correcting for covariates of age, sex, and time from injury (Pearson r = 0.44, P < .01). Inverting the computed direction using transport-based morphometry illustrates physical shifts in fractional anisotropy in the corpus callosum (increase) and within the optic radiations, corticospinal tracts, and anterior thalamic radiations (decrease) with declining reaction time. The observed shifts are consistent with biologic pathways underlying the visual-spatial interpretation and response-selection aspects of reaction time. CONCLUSIONS: Transport-based morphometry discovers complex white matter injury underlying postconcussive reaction time in an automated manner. The potential influences of edema and axonal loss are visualized in the visual-spatial interpretation and response-selection pathways. Transport-based morphometry can bridge the gap between brain microstructure and function in diseases in which the structural basis is unknown.

Chromium toxicity mediated by application of chloride and sulfate ions in Vertisol of Central India.

Chromium (Cr) is one of the toxic metals adversely affecting organisms including humans in the ecosystems, and it is present in considerable concentration in the tannery industrial effluent. Toxicity expression of Cr is suspected to be influenced considerably by other accompanying ions present in the effluent used for irrigation. In a screen house experiment, interactive effects of chloride and sulfate ions in a Vertisol on uptake of Cr by spinach crop were investigated and treatments imposed were three levels each of Cr (0, 50, 100 mg kg-1), chloride (Cl-) (0, 25, 50 mM kg-1), and sulfur (S) (0, 4, 8 mM kg-1) in possible combinations. Plant growth parameters and leaf Cr concentrations were recorded to find out the effect of anions on Cr dynamics in the plant. Increasing the concentration of Cl- ions in soil reduced the Cr concentration in both root and shoot. Similarly, increasing the concentration of S from 4 to 8 mM kg-1 also reduced the concentration and uptake of Cr. Application of sulfate ions augmented the plant growth and counters the negative effect of Cl- ions and Cr. Thus, the study revealed that the addition of S fertilizers could minimize the Cr toxicity in high Cr contaminated soils.