Two Dimensional Effective Electron Mass at the Fermi Level in Quantum Wells of III-V, Ternary and Quaternary Semiconductors

In this paper we study the influence of strong electric field on the two dimensional (2D)effective electron mass (EEM) at the Fermi level in quantum wells of III-V, ternary and quaternary semiconductors within the framework of k x p formalism by formulating a new 2D electron energy spectrum. It appears taking quantum wells of InSb, InAs, Hg(1-x)Cd(x)Te and In(1-x)Ga(x)As(1-y)P(y) lattice matched to InP as examples that the EEM increases with decreasing film thickness, increasing electric field and increases with increasing surface electron concentration exhibiting spikey oscillations because of the crossing over of the Fermi level by the quantized level in quantum wells and the quantized oscillation occurs when the Fermi energy touches the sub-band energy. The electric field makes the mass quantum number dependent and the oscillatory mass introduces quantum number dependent mass anisotropy in addition to energy. The EEM increases with decreasing alloy composition where the variations are totally band structure dependent. Under certain limiting conditions all the results for all the cases get simplified into the well-known parabolic energy bands and thus confirming the compatibility test. The content of this paper finds three applications in the fields of nano-science and technology.

Measurement of the Effective Weak Mixing Angle in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} Events

We present a measurement of the fundamental parameter of the standard model, the weak mixing angle sin^{2}θ_{eff}^{ℓ} which determines the relative strength of weak and electromagnetic interactions, in pp[over ¯]→Z/γ^{*}→e^{+}e^{-} events at a center of mass energy of 1.96 TeV, using data corresponding to 9.7 fb^{-1} of integrated luminosity collected by the D0 detector at the Fermilab Tevatron. The effective weak mixing angle is extracted from the forward-backward charge asymmetry as a function of the invariant mass around the Z boson pole. The measured value of sin^{2}θ_{eff}^{ℓ}=0.23147±0.00047 is the most precise measurement from light quark interactions to date, with a precision close to the best LEP and SLD results.

Association of Clozapine with Seizures: A Brief Report Involving 222 Patients Prescribed Clozapine

OBJECTIVE

To study the prevalence and incidence of seizures in patients prescribed clozapine.

METHODS

The treatment records of 222 patients commenced on clozapine were retrospectively reviewed during the period of January 2007 to June 2014 to evaluate the prevalence of seizures before and after starting clozapine.

RESULTS

The majority of patients commenced on clozapine were male (65%), single (65%), and unemployed (57%). The mean (± standard deviation) dose of clozapine was 277.9 ± 102.5 mg/day. A history of seizure was present in 6 patients who were also prescribed antiepileptic medication; of these 6 patients, only 1 case had recurrence of seizure while taking clozapine due to poor compliance with ongoing antiepileptic medication. The incidence rate of new-onset seizure with clozapine was 6% (12/216). Most patients who developed seizures were male, aged between 24 and 41 years, and had a long duration of illness (≥ 10 years). The risk of seizure was associated with the dose of clozapine used: 3% (5/159) with dose up to 300 mg/day, 8% (4/49) with 325 to 500 mg/day, and 38% (3/8) in those receiving > 500 mg/day. More than half of the patients (7/12) who developed seizures while prescribed clozapine were managed with reduction in the dose of clozapine. In one-third of cases (4/12) an antiepileptic medication was added and in 1 case, clozapine was stopped. All patients who continued on clozapine remained seizure-free at follow-up that ranged from 6 months to 4 years.

CONCLUSION

The incidence of seizures with clozapine was 6% and the risk of seizures increased with higher doses.

Genotype-Phenotype Correlations in CYP1B1-Associated Primary Congenital Glaucoma Patients Representing Two Large Cohorts from India and Brazil

BACKGROUND

Primary congenital glaucoma (PCG), occurs due to the developmental defects in the trabecular meshwork and anterior chamber angle in children. PCG exhibits genetic heterogeneity and the CYP1B1 gene has been widely implicated worldwide. Despite the diverse mutation spectra, the clinical implications of these mutations are yet unclear. The present study attempted to delineate the clinical profile of PCG in the background of CYP1B1 mutations from a large cohort of 901 subjects from India (n=601) and Brazil (n=300).

METHODS

Genotype-phenotype correlations was undertaken on clinically well characterized PCG cases from India (n=301) and Brazil (n=150) to assess the contributions of CYP1B1 mutation on a set of demographic and clinical parameters. The demographic (gender, and history of consanguinity) and quantitative clinical (presenting intraocular pressure [IOP] and corneal diameter [CD]) parameters were considered as binary and continuous variables, respectively, for PCG patients in the background of the overall mutation spectra and also with respect to the prevalent mutations in India (R368H) and Brazil (4340delG). All these variables were fitted in a multivariate logistic regression model using the Akaike Information Criterion (AIC) to estimate the adjusted odds ratio (OR) using the R software (version 2.14.1).

RESULTS

The overall mutation spectrum were similar across the Indian and Brazilian PCG cases, despite significantly higher number of homozygous mutations in the former (p=0.024) and compound heterozygous mutations in the later (p=0.012). A wide allelic heterogeneity was observed and only 6 mutations were infrequently shared between these two populations. The adjusted ORs for the binary (demographic) and continuous (clinical) variables did not indicate any susceptibility to the observed mutations (p>0.05).

CONCLUSIONS

The present study demonstrated a lack of genotype-phenotype correlation of the demographic and clinical traits to CYP1B1 mutations in PCG at presentation. However, the susceptibility of these mutations to the long-term progression of these traits are yet to be deciphered.

Tevatron constraints on models of the Higgs boson with exotic spin and parity using decays to bottom-antibottom quark pairs

Combined constraints from the CDF and D0 Collaborations on models of the Higgs boson with exotic spin J and parity P are presented and compared with results obtained assuming the standard model value JP=0+. Both collaborations analyzed approximately 10  fb(-) of proton-antiproton collisions with a center-of-mass energy of 1.96 TeV collected at the Fermilab Tevatron. Two models predicting exotic Higgs bosons with JP=0- and JP=2+ are tested. The kinematic properties of exotic Higgs boson production in association with a vector boson differ from those predicted for the standard model Higgs boson. Upper limits at the 95% credibility level on the production rates of the exotic Higgs bosons, expressed as fractions of the standard model Higgs boson production rate, are set at 0.36 for both the JP=0- hypothesis and the JP=2+ hypothesis. If the production rate times the branching ratio to a bottom-antibottom pair is the same as that predicted for the standard model Higgs boson, then the exotic bosons are excluded with significances of 5.0 standard deviations and 4.9 standard deviations for the JP=0- and JP=2+ hypotheses, respectively.

Leiomyoma of broad ligament mimicking ovarian malignancy- report of a unique case

Tumors of the broad ligament are uncommon. Leiomyoma, which is the commonest female genital neoplasm, is also the most common solid tumor of the broad ligament. Leiomyomas affect 30% of all women of reproductive age but the incidence of broad-ligament leiomyoma is <1%. These benign tumors are usually asymptomatic. A case is being described where a 52 year old presented with gradual abdominal swelling which was clinically and radiologically diagnosed as ovarian malignancy. On abdominal and bimanual palpation a soft cystic mass was noted in the right pelvic region. CA 125 was mildly raised. CEA, CA 19.9 levels were within normal limit. The radiological diagnosis was ovarian cyst with possibility of malignant changes. Staging laparotomy and histopathological examination of the resected specimen revealed a right sided broad ligament leiomyoma with cystic changes. The degenerative changes in the leiomyoma lead to the clinical and radiological diagnostic confusion. Thus, though uncommon, broad ligament leiomyoma should be considered during evaluation of adnexal masses for optimal patient management. The above description of leiomyoma in the broad ligament is a highly unique case and thus deserves appropriate attention.

Cavitating lung disease due to concomitant drug resistant tuberculosis and invasive pulmonary Aspergillosis in a post-partum patient: A case report

Many disorders can present as cavitating lesions in the lung. In this case report, a case of mixed infection with drug resistant tuberculosis and invasive pulmonary aspergillosis in a post-partum patient has been presented.

Measurement of the B(s)(0) lifetime in the flavor-specific decay channel B(s)(0)→D(s)(-)μ(+)νX

We present an updated measurement of the B(s)(0) lifetime using the semileptonic decays B(s)(0)→D(s)(-)μ(+)νX, with D(s)(-)→ϕπ(-) and ϕ→K(+)K(-) (and the charge conjugate process). This measurement uses the full Tevatron Run II sample of proton-antiproton collisions at √[s]=1.96  TeV, comprising an integrated luminosity of 10.4  fb(-1). We find a flavor-specific lifetime τ(fs)(B(s)(0))=1.479±0.010(stat)±0.021(syst)  ps. This technique is also used to determine the B(0) lifetime using the analogous B(0)→D(-)μ(+)νX decay with D(-)→ϕπ(-) and ϕ→K(+)K(-), yielding τ(B(0))=1.534±0.019(stat)±0.021(syst)  ps. Both measurements are consistent with the current world averages, and the B(s)(0) lifetime measurement is one of the most precise to date. Taking advantage of the cancellation of systematic uncertainties, we determine the lifetime ratio τ(fs)(B(s)(0))/τ(B(0))=0.964±0.013(stat)±0.007(syst).

Measurement of the forward-backward asymmetry in the production of B(±) mesons in pp̄ collisions at √s=1.96 TeV

We present a measurement of the forward-backward asymmetry in the production of B(±) mesons, A(FB)(B(±)), using B(±)→J/ψK(±) decays in 10.4  fb(-1) of pp̄ collisions at sqrt[s]=1.96  TeV collected by the D0 experiment during Run II of the Tevatron collider. A nonzero asymmetry would indicate a preference for a particular flavor, i.e., b quark or ̄b antiquark, to be produced in the direction of the proton beam. We extract A(FB)(B(±)) from a maximum likelihood fit to the difference between the numbers of forward- and backward-produced B(±) mesons. We measure an asymmetry consistent with zero: A(FB)(B(±))=[-0.24±0.41  (stat)±0.19  (syst)]%.

Serum fetuin-A concentration predicts glycaemic outcomes in people with prediabetes: a prospective study from eastern India

AIM

To evaluate the role of fetuin-A levels in predicting glycaemic outcomes (progression to diabetes or reversion to normoglycaemia) in people with prediabetes.

METHODS

A total of 2119 people were screened, of whom 144 people with prediabetes, 50 people with normoglycaemia and 66 people with newly diagnosed diabetes underwent estimation of fasting insulin, fetuin-A, interleukin-6, interleukin-1β, tumour necrosis factor-α, lipid and 25-hydroxyvitamin-D levels and assessment of non-alcoholic fatty liver disease using ultrasonography and the fatty liver index. People with prediabetes were followed and analysed according to glycaemic outcome and quartile of fetuin-A level.

RESULTS

Fetuin-A, interleukin-1β, interleukin-6, tumour necrosis factor-α and triglyceride levels and presence of non-alcoholic fatty liver disease increased across the glycaemic spectrum and were highest in people with diabetes. A total of 32 people with prediabetes reverted to normoglycaemia, 23 progressed to diabetes and 65 remained with prediabetes over a mean ± sd follow-up of 32.12 ± 8.4 months. People progressing to diabetes had higher baseline glycaemia rates, fetuin-A levels, interleukin-1β levels, fatty liver index scores and prevalence of non-alcoholic fatty liver disease and lower 25-hydroxyvitamin-D levels. People with prediabetes in the highest fetuin-A quartile had the highest risk of progression to diabetes (relative risk 2.68, 95% CI 0.95-7.55; P = 0.06) and the lowest rate of reversion to normoglycaemia (relative risk 0.27, 95% CI 0.08-0.85; P = 0.03). Fetuin-A levels correlated with interleukin-1β levels (r = 0.420; P < 0.001), interleukin-6 levels (r = 0.231; P = 0.022) and fatty liver index scores (r = 0.319; P < 0.001). Cox regression showed that higher fetuin-A levels and higher BMI and lower 25-hydroxyvitamin-D levels were predictive of lower rates of reversion to normoglycaemia. Age, triglyceride levels, and interleukin-6 and interleukin-1β levels were predictive of progression to diabetes.

CONCLUSIONS

Increased fetuin-A level has an adverse impact on glycaemic outcomes in prediabetes. This study highlights the importance of fetuin-A as a predictor of glycaemic outcomes in prediabetes.

Constraints on models for the Higgs boson with exotic spin and parity in VH → Vbb final states

We present constraints on models containing non-standard-model values for the spin J and parity P of the Higgs boson H in up to 9.7 fb(-1) of pp collisions at sqrt[s] = 1.96 TeV collected with the D0 detector at the Fermilab Tevatron Collider. These are the first studies of Higgs boson J(P) with fermions in the final state. In the ZH → ℓℓbb, WH → ℓνbb, and ZH → ννbb final states, we compare the standard model (SM) Higgs boson prediction, J(P) = 0(+), with two alternative hypotheses, J(P) = 0(-) and J(P) = 2(+). We use a likelihood ratio to quantify the degree to which our data are incompatible with non-SM J(P) predictions for a range of possible production rates. Assuming that the production rate in the signal models considered is equal to the SM prediction, we reject the J(P) = 0(-) and J(P) = 2(+) hypotheses at the 97.6% CL and at the 99.0% CL, respectively. The expected exclusion sensitivity for a J(P) = 0(-) (J(P) = 2(+)) state is at the 99.86% (99.94%) CL. Under the hypothesis that our data are the result of a combination of the SM-like Higgs boson and either a J(P) = 0(-) or a J(P) = 2(+) signal, we exclude a J(P) = 0(-) fraction above 0.80 and a J(P) = 2(+) fraction above 0.67 at the 95% CL. The expected exclusion covers J(P) = 0(-) (J(P) = 2(+)) fractions above 0.54 (0.47).

Congenital corneal anesthesia

PURPOSE

To report the various clinical presentations of congenital corneal anesthesia.

METHODS

The medical records of children diagnosed with congenital corneal anesthesia between January 2006 and June 2012 at the L.V. Prasad Eye Institute, Hyderabad, India, were retrospectively reviewed for demographics and clinical characteristics.

RESULTS

A total of 40 patients (29 males) were included. Median age at presentation was 12 months (interquartile range, 6-60 months). Bilateral involvement was noted in 28 cases (70%). Generalized pain insensitivity with anhidrosis was documented in 10 cases (25%). The spectrum of corneal lesions included geographic epithelial defects (32 eyes), sterile ulcers (15 eyes), sterile ulcers with hypopyon (11 eyes), secondary bacterial keratitis (2 eyes), superficial/ deep corneal vascularisation (5 eyes). Generalized anesthesia with self-mutilating behavior was recognized in 10 cases. In all cases, sterile corneal ulcers resolved on average 30 days after permanent 2/3-width paramedian tarsorrhapy. One eye progressed to the stage of anterior staphyloma and subsequently underwent auto evisceration. Four eyes that underwent keratoplasty for visual rehabilitation had poor outcomes.

CONCLUSIONS

Accurate diagnosis, recognition of risk factors, and thorough neurological assessment is important for lessening long-term sequelae of congenital corneal anesthesia. Judicious use of tear substitutes and expedited tarsorrhaphy is crucial to restoration of useful vision in these children.