Acoustic particle trapping driven by axial primary radiation force in shaped traps.

We study particle trapping driven by the axial primary radiation force (A-PRF) in shaped traps exposed to standing bulk acoustic waves (S-BAW) using numerical simulations and experiments. The utilization of the stronger A-PRF as the main retention force is a consequence of standing-wave formation along the flow direction, instead of the orthogonal direction as in the case of traditionally used lateral-PRF S-BAW trapping setups. The study of particle dynamics reveals that the competition between A-PRF and viscous drag force governs particle trajectory. The ratio of the acoustic energy to the viscous work (ß) provides a general criterion for particle trapping at a distinctive off-node site that is spatially controllable. Particles get trapped for ß≥ß_{cr} at some distance away from the nodal plane and the distance varies as ß^{-c} (c=0.6-1.0). The use of A-PRF as the retention force could potentially allow traditional S-BAW trapping systems to envisage high-throughput advancements surpassing the current standards in cell-handling unit operations.

Dynamic chiral magnetic effect and anisotropic natural optical activity of tilted Weyl semimetals.

We study the dynamic chiral magnetic conductivity (DCMC) and natural optical activity in an inversion-broken tilted Weyl semimetal (WSM). Starting from the Kubo formula, we derive the analytical expressions for the DCMC for two different directions of the incident electromagnetic wave. We show that the angle of rotation of the plane of polarization of the transmitted wave exhibits remarkable anisotropy and is larger along the tilt direction. This striking anisotropy of DCMC results in anisotropic optical activity and rotary power, which can be experimentally observed as a topological magneto-electric effect of inversion-broken tilted WSMs. Finally, using the low energy Hamiltonian, we show that the DCMC follows the universal [Formula: see text] decay in the high frequency regime. In the low frequency regime, however, the DCMC shows sharp peaks at the tilt dependent effective chemical potentials of the left-handed and right-handed Weyl points. This can serve as a signature to distinguish between the type-I and type-II Weyl semimetals.

Chiral Magnetic Effect of Hot Electrons.

We propose a way to observe the chiral magnetic effect in noncentrosymmetric Weyl semimetals under the action of a strong electric field, via the nonlinear part of their I-V characteristic that is odd in the external magnetic field, or odd-in-magnetic field voltages in electrically open circuits. This effect relies on valley-selective heating in such materials, which, in general, leads to nonequilibrium valley population imbalances. In the presence of an external magnetic field, such a valley-imbalanced Weyl semimetal will, in general, develop an electric current along the direction of the magnetic field-the chiral magnetic effect. We also discuss a specific experimental setup to observe the chiral magnetic effect of hot electrons.

Berry phase theory of planar Hall effect in topological insulators.

The appearance of negative longitudinal magnetoresistance (LMR) in topological semimetals such as Weyl and Dirac semimetals is understood as an effect of chiral anomaly, whereas such an anomaly is not well-defined in topological insulators. Nevertheless, it has been shown recently in both theory and experiments that nontrivial Berry phase effects can give rise to negative LMR in topological insulators even in the absence of chiral anomaly. In this paper, we present a quasi-classical theory of another intriguing phenomenon in topological insulators - also ascribed to chiral anomaly in Weyl and Dirac semimetals- the so-called planar Hall effect (PHE). PHE implies the appearance of a transverse voltage in the plane of applied non-parallel electric and magnetic fields, in a configuration in which the conventional Hall effect vanishes. Starting from Boltzmann transport equations we derive the expressions for PHE and LMR in topological insulators in the bulk conduction limit, and show the important role played by orbital magnetic moment. Our theoretical results for magnetoconductance with non-parallel electric and magnetic fields predict detailed experimental signatures in topological insulators - specifically of planar Hall effect - that can be observed in experiments.

Nature of spiral state and absence of electric polarisation in Sr-doped YBaCuFeO5 revealed by first-principle study.

Experimental results on YBaCuFeO5, in its incommensurate magnetic phase, appear to disagree on its ferroelectric response. Ambiguity exists on the nature of the spiral magnetic state too. Using first-principles density functional theory (DFT) calculations for the parent compound within LSDA + U + SO approximation, we reveal the nature of spiral state. The helical spiral is found to be more stable below the transition temperature as spins prefer to lie in ab plane. Dzyaloshinskii-Moriya (DM) interaction turns out to be negligibly small and the spin current mechanism is not valid in the helical spiral state, ruling out an electric polarisation from either. These results are in very good agreement with the recent, high quality, single-crystal data. We also investigate the magnetic transition in YBa1-xSrxCuFeO5 for the entire range (0 ≤ x ≤ 1) of doping. The exchange interactions are estimated as a function of doping and a quantum Monte Carlo (QMC) calculation on an effective spin Hamiltonian shows that the paramagnetic to commensurate phase transition temperature increases with doping till x = 0.5 and decreases beyond. These observations are consistent with experimental findings.

Chiral Anomaly as the Origin of the Planar Hall Effect in Weyl Semimetals.

In condensed matter physics, the term "chiral anomaly" implies the violation of the separate number conservation laws of Weyl fermions of different chiralities in the presence of parallel electric and magnetic fields. One effect of the chiral anomaly in the recently discovered Dirac and Weyl semimetals is a positive longitudinal magnetoconductance. Here we show that chiral anomaly and nontrivial Berry curvature effects engender another striking effect in Weyl semimetals, the planar Hall effect (PHE). Remarkably, the PHE manifests itself when the applied current, magnetic field, and the induced transverse "Hall" voltage all lie in the same plane, precisely in a configuration in which the conventional Hall effect vanishes. In this work we treat the PHE quasiclassically, and predict specific experimental signatures for type-I and type-II Weyl semimetals that can be directly checked in experiments.

Evaluation of Iron Store by Serum Ferritin in Healthy Blood Donors of Bangladesh.

Iron stores in the body exist primarily in the form of ferritin. Small amounts of ferritin secreted into the plasma and plasma ferritin is positively correlated with the size of the total body iron stores. The present study conducted to determine the iron status using the serum ferritin level among healthy Bangladeshi blood donors. The present cross sectional study was conducted in the Department of Transfusion Medicine, Dhaka Medical College, Dhaka, Bangladesh from July 2011 to June 2012. Blood donor signed informed consent and has satisfactory pre-donation health assessment and satisfactory post-donation blood test results were included in the study. Full blood counts were performed within 4 hours of collection using an automated haematology analyzer. Serum ferritin was measured using a validated enzyme immunoassay. Data were analyzed using SPSS version 16 (SPPS Incorporation, Chicago, IL, USA). P value <0.05 was considered as statistically significant. Total 100 blood donors were included in the study, among them 88 were male and 12 were female. Mean±SD of the age of the respondents was 26.8±5.9 years with a range of 19 to 45 years. Mean±SD of heamoglobin level (gm/dl) and total count of Red Blood Cell (million/cmm) were 14.1±1.4 and 5.1±0.4 respectively. Mean±SD of serum ferritin level (ng/ml) was 96.4±69.0ng/ml with a range of 4.1ng/ml to 298.7ng/ml. Among the respondents 9.0% had depleted iron store, 7.0 reduced iron store and 84.0% had normal iron store. Among the respondents 5.0% had iron deficiency anaemia in term of serum ferritin level. Statistically significant difference of serum ferritin level observed between male and female and donors with and without history of previous blood donation. Among the healthy blood donors of Bangladesh abnormal serum ferritin is highly prevalent among blood donors specially among female. Monitoring of iron stores by serum ferritin seems justified in order to identify those with depleted iron stores who will benefit from iron supplementation.

Relationship between Serum Iron Profile and Blood Groups among the Voluntary Blood Donors of Bangladesh.

Blood donation results in a substantial iron loss and subsequent mobilization from body stores. Chronic iron deficiency is a well-recognized complication of regular blood donation. The present study conducted to compare the level of serum ferritin, serum iron, total iron binding capacity (TIBC) and percentage transferrin saturation in different ABO and Rhesus type blood groups among the voluntary blood donors of Bangladesh. The present prospective study included 100 healthy voluntary donors attending at Department of Blood Transfusion, Dhaka Medical College, Dhaka between the periods of July 2013 to Jun 2014. From each donor 10mL venous blood sample was taken and divided into heparinized and non-heparinized tubes for determination of hemoglobin (Hb), hematocrit (Hct), serum iron (SI), total iron binding capacity (TIBC) and serum ferritin by standard laboratory methods. Percentage of transferrin saturation (TS) calculated from serum iron and TIBC. Data were analyzed with SPSS (version 16) software and comparisons between groups were made using student's t-test and one way ANOVA. In the present study mean±SD of age of the respondents was 27.2±6.5 years with a range of 18 to 49 years and 81.0% were male and 19.0% were female. Among the donors 18.0% had blood group A, 35.0% had blood group B, 14.0% had blood group AB and 33.0% had blood group O. Among the donors 91.0% had rhesus positive and 9.0% had rhesus negative. Donors with blood group O had lowest haemoglobin, serum iron and transferring saturation levels. Donors with blood group A had highest TIBC level. Donors with blood group B had lowest serum ferritin level. An independent samples 't' test showed statistically significant difference in serum ferritin and percentage transferrin saturation between blood group AB and blood group O and in percentage transferrin saturation between blood group B and blood group O. One way ANOVA showed that there is no significant difference in haemoglobin, serum iron, serum ferritin and percentage transferring saturation in different ABO and Rh blood grouping categories. Blood donors with blood group O had lowest haemoglobin, serum iron and transferring saturation levels and donors with blood group A had highest TIBC level. Blood donors with blood group B had lowest serum ferritin level. The understanding of the different blood groups ability to retain iron in their system can give an insight into their ability to handle the disease iron deficiency anaemia.

Mapping aboveground woody biomass using forest inventory, remote sensing and geostatistical techniques.

Mapping forest biomass is fundamental for estimating CO2 emissions, and planning and monitoring of forests and ecosystem productivity. The present study attempted to map aboveground woody biomass (AGWB) integrating forest inventory, remote sensing and geostatistical techniques, viz., direct radiometric relationships (DRR), k-nearest neighbours (k-NN) and cokriging (CoK) and to evaluate their accuracy. A part of the Timli Forest Range of Kalsi Soil and Water Conservation Division, Uttarakhand, India was selected for the present study. Stratified random sampling was used to collect biophysical data from 36 sample plots of 0.1 ha (31.62 m × 31.62 m) size. Species-specific volumetric equations were used for calculating volume and multiplied by specific gravity to get biomass. Three forest-type density classes, viz. 10-40, 40-70 and >70% of Shorea robusta forest and four non-forest classes were delineated using on-screen visual interpretation of IRS P6 LISS-III data of December 2012. The volume in different strata of forest-type density ranged from 189.84 to 484.36 m(3) ha(-1). The total growing stock of the forest was found to be 2,024,652.88 m(3). The AGWB ranged from 143 to 421 Mgha(-1). Spectral bands and vegetation indices were used as independent variables and biomass as dependent variable for DRR, k-NN and CoK. After validation and comparison, k-NN method of Mahalanobis distance (root mean square error (RMSE) = 42.25 Mgha(-1)) was found to be the best method followed by fuzzy distance and Euclidean distance with RMSE of 44.23 and 45.13 Mgha(-1) respectively. DRR was found to be the least accurate method with RMSE of 67.17 Mgha(-1). The study highlighted the potential of integrating of forest inventory, remote sensing and geostatistical techniques for forest biomass mapping.

Growing stock and woody biomass assessment in Asola-Bhatti Wildlife Sanctuary, Delhi, India.

Biomass is an important entity to understand the capacity of an ecosystem to sequester and accumulate carbon over time. The present study, done in collaboration with the Delhi Forest Department, focused on the estimation of growing stock and the woody biomass in the so-called lungs of Delhi--the Asola-Bhatti Wildlife Sanctuary in northern Aravalli hills. The satellite-derived vegetation strata were field-inventoried using stratified random sampling procedure. Growing stock was calculated for the individual sample plots using field data and species-specific volume equations. Biomass was estimated from the growing stock and the specific gravity of the wood. Among the four vegetation types, viz. Prosopis juliflora, Anogeissus pendula, forest plantation and the scrub, the P. juliflora was found to be the dominant vegetation in the area, covering 23.43 km(2) of the total area. The study revealed that P. juliflora forest with moderate density had the highest (10.7 m(3)/ha) while A. pendula forest with moderate density had the lowest (3.6 m(3)/ha) mean volume. The mean woody biomass was also found to be maximum in P. juliflora forest with moderate density (10.3 t/ha) and lowest in A. pendula forest with moderate density (3.48 t/ha). The total growing stock was estimated to be 20,772.95 m(3) while total biomass worked out to be 19,366.83 t. A strong correlation was noticed between the normalized difference vegetation index (NDVI) and the growing stock (R(2) = 0.84)/biomass (R(2) = 0.88). The study demonstrated that growing stock and the biomass of the woody vegetation in Asola-Bhatti Wildlife Sanctuary could be estimated with high accuracy using optical remote sensing data.

Identification of swamp deer (Cervus duvauceli duvauceli Cuvier) potential habitat in Jhilmil Jheel Conservation Reserve, Uttarakhand, India using multi-criteria analysis.

The present study aims to identify the potential habitat for swamp deer (Cervus duvauceli duvauceli Cuvier) in Jhilmil Jheel Conservation Reserve in the Uttarakhand province of India using multi-criteria analysis. The study area represents one of the last remnant habitats of the flagship species, the swamp deer in Uttarakhand, which is considered as vulnerable. The study showed that only 6.08% of the study area (225 km(2)) was highly suitable to suitable for the swamp deer. An area of 135.52 km(2) (60.23%) turned out to be moderately suitable. Within the officially designated Conservation Reserve (area 37.84 km(2)), 10.91% (4.13 km(2)) area was found highly suitable to suitable, while 74.19% (28.07 km(2)) happens to be moderately suitable. Only 14 km(2) area, which was found as suitable habitat for swamp deer falls short of the space required by a population of 134 animals. The problem could be mitigated if the agricultural land (2.47 km(2)) adjacent to the Jhilmil Jheel is brought under the Reserve management. This would provide additional area to meet the fodder requirement. The study brings out a particularly grim situation with limited options for conservation and management of the swamp deer in the Indo-Gangetic plains. It also emphasizes the role of geospatial techniques in quick appraisal of habitat attributes and identification of potential sites for protected areas.

Simple, column purification technique for the fully automated radiosynthesis of [18F]fluoroazomycinarabinoside ([18F]FAZA).

A novel fully automated radiosynthesis procedure for the fluorine-18 analog of 1-alpha-D-(5'-deoxy-5'-fluoro-(1S,2R,3S,4S) arabinofuranosyl)-2-nitroimidazole ([(18)F]FAZA) using a commercially available combination column - Chromabond Set V (FDG-base-hydrolysis) - for purification was developed. [(18)F]FAZA was prepared via a one-pot, two-step synthesis using a nuclear interface nucleophilic synthesis module. Nucleophilic fluorination of the precursor molecule, 1-(2,3-di-O-acetyl-5-O-tosyl-alpha-D-arabinofuranosyl)-2-nitroimidazole, with no-carrier added [(18)F]fluoride followed by hydrolysis of the protecting groups with 0.3M NaOH was performed. Purification was carried out using the Chromabond Set V column without any modifications. The overall radiochemical yield obtained was 21.98+/-1.40% (n=5, without decay correction) within a total synthesis period of 51+/-1 min. The radiochemical purity was greater than 95% and devoid of any other chemical impurities. The reported method can easily be adapted in any commercial FDG synthesis module.

Enhanced p-type conductivity and band gap narrowing in heavily Al doped NiO thin films deposited by RF magnetron sputtering.

Stoichiometric NiO, a Mott-Hubbard insulator at room temperature, shows p-type electrical conduction due to the introduction of Ni(2+) vacancies (V(Ni)('')) and self-doping of Ni(3+) ions in the presence of excess oxygen. The electrical conductivity of this important material is low and not sufficient for active device fabrication. Al doped NiO thin films were synthesized by radio frequency (RF) magnetron sputtering on glass substrates at a substrate temperature of 250 °C in an oxygen + argon atmosphere in order to enhance the p-type electrical conductivity. X-ray diffraction studies confirmed the correct phase formation and also oriented growth of NiO thin films. Al doping was confirmed by x-ray photoelectron spectroscopic studies. The structural, electrical and optical properties of the films were investigated as a function of Al doping (0-4 wt%) in the target. The room temperature electrical conductivity increased from 0.01-0.32 S cm (-1) for 0-4% Al doping. With increasing Al doping, above the Mott critical carrier density, energy band gap shrinkage was observed. This was explained by the shift of the band edges due to the existence of exchange and correlation energies amongst the electron-electron and hole-hole systems and also by the interaction between the impurity quasi-particle system.

Status of maternal and new born care at first referral units in the state of West Bengal.

A study was conducted in 12 First Referral Units (FRUs), selected through multistage sampling, from 6 districts of West Bengal. Infrastructure facilities, record keeping, referral system and MCH indicators related to newborn care were documented. Data was collected by review of records, interview and observation using a pre-designed proforma. Inadequate infrastructure facilities (e.g. no sanctioned posts of specialists, no blood bank at rural hospitals declared as First Referral Units etc.); poor utilization of equipment like neonatal resuscitation sets, radiant warmer etc, lack of training of the service providers were evident. Records/registers were available but incomplete. Referral system was found to be almost nonexistent. Most of the deliveries (86.1%) were normal delivery. Deliveries (87.71%) and immediate neonatal resuscitation (94.9%) were done mostly by nursing personnel. Institution based maternal, perinatal and early neonatal mortality rates were found to be 5.6, 62.4 and 25.2 per 1000 live births respectively. Eclampsia (48.9%), hemorrhage (17.7%), puerperal sepsis (7.1%) were reported to be major causes of maternal mortality. Common causes of early neonatal mortality were birth asphyxia (54.3%), sepsis (14.6%) and prematurity/LBW (12.4%).

Utilisation pattern of blood in a teaching hospital of Kolkata.

An annual utilisation of blood transfusion services at several depts. of R.G. Kar Medical College and Hospital, Kolkata were assessed among a sample of 3122 patients selected by Systematic Random Sampling Technique from the register made available in the blood bank there. Record analysis revealed that overall 79.4% of supplied blood units were actually transfused, wastage of 21.6%. Wastage was maximum in the Department of Gynae & Obstetrics (33.11%) and Surgery (32.87%). Only single unit of blood was requisitioned and transfused for 5.44% & 30.90% of the patients respectively. Most common indications of blood transfusion were for surgical cases (37.92%), followed by anaemia (34.80%) and haemorrhage (26.92%). The use of blood and blood products merit attention, appraisal and instructional guiding accordingly.

A patient with optic pathway glioma, scoliosis, Chiari type I malformation and syringomyelia: is it Neurofibromatosis type 1?

A 22 years old girl had features of optic pathway glioma, scoliosis, Chiari type 1 malformation and cervical syringomyelia. She had no cutaneous lesions. We considered this combination to be more than coincidental and argue in favour of considering the case as a variant form of Neurofibromatosis type 1. The relevent literature in favour of our contention has been reviewed.

Analytical studies on the impact of land reclamation on ground water flow.

Land reclamation has been a common practice to produce valuable land in coastal areas. The impact of land reclamation on coastal environment and marine ecology is well recognized and widely studied. It has not been recognized yet that reclamation may change the regional ground water regime, which may in turn modify the coastal environment, flooding pattern, and stability of slopes and foundations. This paper represents the first attempt to examine quantitatively the effect of reclamation on ground water levels. Analytical solutions are developed to study the ground water change in response to reclamation based on two hypothetical models. In the first model, the ground water flow regime changes only in the hillside around the reclamation areas. In the second model, the ground water regime changes in the entire hill. Both models assume that the ground water flow is in a steady state and satisfies the Dupuit assumptions. Hypothetical examples are used to demonstrate how the ground water level, ground water divide and ground water submarine discharge will change with the scale and hydraulic conductivity of the reclamation materials. The results show that the change of ground water regime depends mainly on the length of the reclaimed area and the values of hydraulic conductivity of the reclaimed materials. It is also seen that the reclamation may impact not only the ground water regime near the coast areas around the reclamation site, but also that in the coast areas opposite the reclamation area. A reclamation site near Tseung Kwan O in the New Territories in Hong Kong, China, is used as a case study to discuss the possible modification of the ground water system caused by reclamation.

Referral for minor mental illness: a qualitative study.

BACKGROUND: Mild depression and anxiety are common problems in general practice. They can be managed by the general practitioner (GP) alone or referred. Previous quantitative studies have shown a large variation between GPs in terms of referral behaviour. The reasons for this variation are not fully understood. AIM: To describe and analyse GP's decision-making processes when considering who should be treating patients with minor mental illness, using a qualitative method. DESIGN OF STUDY: A qualitative interview study. SETTING: Twenty-three GPs in east London and Essex. METHOD: Subjects were chosen using a purposive sampling strategy and participated in one-to-one semi-structured interviews. A grounded theory approach was used for analysis. RESULTS: Two distinct referral strategies were identified--the 'containment' and the 'conduit' approaches. In addition, referrals were found to be of two types--proactive 'referrals to' and reactive 'referrals away'; for minor mental illness the 'referrals away' were found to predominate. Emotive as well as rational responses informed GP decision making on referral. CONCLUSIONS: Explanations of the variation in referral rates need to recognise the emotive responses of individual GPs to minor mental illness. The contribution of guidelines, which assume consistently rational responses to illness, may therefore be limited.