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We include a fully coupled treatment of metal and dust enrichment into the Delphi semi-analytic model of galaxy formation to explain the dust content of 13 Lyman Break Galaxies (LBGs) detected by the Atacama Large millimetre Array (ALMA) REBELS Large Program at $z\simeq 7$. We find that the galaxy dust mass, $M_d$, is regulated by the combination of SNII dust production, astration, shock destruction, and ejection in outflows; grain growth (with a standard timescale $\tau_0= 30$ Myr) plays a negligible role. The model predicts a dust-to-stellar mass ratio of $\sim 0.07-0.1\%$ and a UV-to-total star formation rate relation such that $log (\psi_{\rm UV}) = -0.05 ~[log (\psi)]^{2} + 0.86 ~log(\psi) -0.05$ (implying that 55-80\% of the star formation is obscured) for REBELS galaxies with stellar mass $M_* = 10^{9-10} M_\odot$. This relation reconciles the intrinsic UV luminosity of LBGs with their observed luminosity function at $z=7$. However, 2 out of the 13 systems show dust-to-stellar mass ratios ($\sim 0.94-1.1\%$) that are up to $18\times$ larger than expected from the fiducial relation. Due to the physical coupling between dust and metal enrichment, even decreasing $\tau_0$ to very low values (0.3 Myr) only increases the dust-to-stellar mass ratio by a factor $ \sim 2$. Given that grain growth is not a viable explanation for such high observed ratios of the dust-to-stellar mass, we propose alternative solutions., Comment: Accepted to MNRAS

ALMA observations have revealed the presence of dust in the first generations of galaxies in the Universe. However, the dust temperature Td remains mostly unconstrained due to the few available FIR continuum data at redshift $z$ > 5. This introduces large uncertainties in several properties of high-$z$ galaxies, namely their dust masses, infrared luminosities, and obscured fraction of star formation. Using a new method based on simultaneous [C $\scriptstyle \rm II$] 158-μm line and underlying dust continuum measurements, we derive Td in the continuum and [C $\scriptstyle \rm II$] detected $z$ ≈ 7 galaxies in the ALMA Large Project REBELS sample. We find 39 < Td < 58 K, and dust masses in the narrow range Md = (0.9-3.6) × 107 M⊙. These results allow us to extend for the first time the reported Td($z$) relation into the Epoch of Reionization. We produce a new physical model that explains the increasing Td($z$) trend with the decrease of gas depletion time, tdep = Mg/SFR, induced by the higher cosmological accretion rate at early times; this hypothesis yields Td ∝ (1 + $z$)0.4. The model also explains the observed Td scatter at a fixed redshift. We find that dust is warmer in obscured sources, as a larger obscuration results in more efficient dust heating. For UV-transparent (obscured) galaxies, Td only depends on the gas column density (metallicity), $T_{\rm d} \propto N_{\rm H}^{1/6}$ (Td ∝ Z-1/6). REBELS galaxies are on average relatively transparent, with effective gas column densities around NH ≃ (0.03-1) × 1021 cm-2. We predict that other high-$z$ galaxies (e.g. MACS0416-Y1, A2744-YD4), with estimated Td ≫ 60 K, are significantly obscured, low-metallicity systems. In fact, Td is higher in metal-poor systems due to their smaller dust content, which for fixed LIR results in warmer temperatures.

Background: Childbirth is associated with significant physiological changes as well as challenges related to psychiatric disorders. Postpartum depression (PPD) is one such condition associated with high levels of morbidity and mortality. Screening postpartum women for early identification of depression and its prompt treatment should be a crucial component of postnatal health care. Assessment of prevalence and correlates of postpartum depression hence becomes important. Methods: Cross-sectional assessment of mothers (n=250) during postnatal visits to the family planning clinics between four weeks and one year of delivery, using Edinburg Postpartum Depression Scale (EPDS), Social Support Questionnaire and a structured questionnaire for the assessment of psychosocial risk factors was carried out in a tertiary care postgraduate teaching hospital of north Kerala. Multivariate Regression Analysis was used to identify the risk factors for PPD. Results: 27.6% had postpartum depression (score of >11 in EPDS), and 18.4% had suicidal ideation. Factors associated with the presence of PPD included alcohol use of husband, marital discord, lack of family support and lack of physical help during the postnatal period. Difficulties during labour, the gender of the baby or postnatal complications did not have a significant association with PPD. Though there was a negative correlation between Social Support Scale (SSS) total score and EPDS score, it was not statistically significant. (Pearson’s co-relation coefficient= -0.084, p= 0.186). Conclusion: Prevalence of depression in postnatal women is very high. Modifiable psychosocial factors have a close association with PPD, and these are opportunities for intervention as well. Considering the morbidity and mortality linked to untreated PPD, screening of postnatal women and routine provision of therapeutic services to them is suggested.

Religion and spirituality (R/S) are embedded in all aspects of life in India, a predominantly rural economy. The aim of this mixed methods study was to assess the associations between a culturally tailored intervention and preexisting religious/spiritual (R/S) practices with indicators of well-being and factors which contribute to happiness among elderly rural women from Haryana state, India. The study consisted of three groups: field experimental group (FEG; n = 24); practitioners of preexisting R/S practices for at least 6 weeks Satsang (SG, n = 54), Brahma Kumaris (BKG, n = 54), and Radha Soami (RSG, n = 30), and non-practitioners of R/S practices (n = 64). All groups completed self-report measures of overall happiness and life satisfaction, global health, quality of life, and health status and physical health. Results revealed that FEG participants improved significantly on physical health, body balancing, and self-care; no changes were observed on the other well-being measures following the intervention. Practitioners of preexisting R/S practices were found significantly different from the non-practitioners on some indicators of health, quality of life, and well-being. Qualitative measures pointed to the importance of R/S and family and interpersonal relationships among elderly rural women.

Introduction Poultry farm workers are exposed to various hazardous biological agents in organic dust. Particulate dust, endotoxins and (1–3) β-d-glucans) in poultry dust have been implicated in adverse respiratory effects including work-related asthma. Method The study was conducted at various sites of a South African poultry farm consisting of broilers, rearing, laying, hatchery and catching processes. Personal inhalable samples were collected from 298 workers using filtration technique at a flow rate of 2 l/min for the entire work shift. Filter extracts were analysed for (1–3) β-d-glucan and endotoxin using the endpoint Glucatell and Limulus amebocyte lysate test (LAL) assays, respectively. Total inhalable dust concentration was also determined. Data were analysed using STATA 12. Results Dust particulate levels had an overall geometric mean (GM) of 11.04 mg/m 3 and differed by farm process The mean dust particulate concentration was highest in the rearing department (GM=54.04 mg/m 3 , GSD=3.74) followed by hatchery (GM=36.25 mg/m 3 , GSD=3.46). The automated egg laying farms recorded elevated concentrations of dust particulate (GM=35.23 mg/m 3 ), endotoxin (GM=880 EU/m 3 ) and (1–3) β-d-glucan (GM=136 ng/m 3 ) levels compared to the manual laying system (GM=3.95 mg/m 3 ; GM=680 EU/m 3 ; GM=97 ng/m 3 ). Large broilers had relatively higher total dust particulate and endotoxin concentrations while small broilers had higher (1–3) β-d-glucan levels. The catching crew were found to have the highest concentrations of (1–3) β-d-glucan (GM=644 ng/m 3 , GSD=1.89) and endotoxin levels (GM=23902 EU/m 3 , GSD=9.64). Discussion This exposure characterisation study revealed that total inhalable dust, endotoxin and (1–3) β-d-glucans were very high and significantly variable between the five main poultry farming processes. Workers in all processes were exposed to endotoxin levels above the recommended OEL of 90 EU/m 3 . Inhalable dust particulate was also above the 10 mg/m 3 OEL for total inhalable dust in the hatchery, rearing and automated laying farms. Poultry catchers appear to be at greatest risk of developing adverse respiratory health effects due to endotoxins and (1–3) β-d-glucans.

Risk of dental injury from contact sports can be prevented by the use of mouthguards. Dentists provide excellent information regarding mouthguards. Thus, the aim was to assess the awareness among dentists regarding the same, the level of training in fabricating a mouthguard and whether they regularly recommend one for their athletically active patients.This institutional cross-sectional survey was conducted in the Department of Orthodontics, Government Dental College, Kottayam, and Kerala, India. An online form was sent out to 1500 offices and departments in dental institutions through email with a time period of 1 month given to fill responses and was analyzed using descriptive statistics.A response from 640 was recorded; most of them had not received or had fabricated a mouthguard during their dental training or private practice, even though one-third recommended one to their athletically active patients with a lack of formal training being the reason for not routinely advocating mouthguard usage. Most were aware of more than one type of mouthguards and recommended customized one for the same, however, more than half were not aware of a different type intended for orthodontic patients.It is not a routine practice currently, among general dentists and specialists alike, in our country, to prescribe a mouthguard. It is time that the dental fraternity spread awareness for the prevention of injuries. A relook into the academic curriculum while advocating the use of customized mouthguards to patients due to contact sports is required.

With the ever growing usage of various wireless technologies and services, more and more handheld devices are equipped with multiple radio transceivers (e.g., LTE, WiFi, Bluetooth, and GNSS). As a result, in-device coexistence interference has become a serious problem due to the extreme proximity of multiple radio transceivers within the same device. It has been shown by the studies of 3GPP that for some specific frequency bands, concurrent operations of LTE and ISM/GNSS radios working in adjacent or sub-harmonic frequencies will result in significant in-device coexistence interference that cannot be completely eliminated by filter technology. This motivates 3GPP to introduce signaling mechanisms and procedures, which enable the devices to effectively solve the indevice coexistence problems with help from the LTE network. This article first discusses the scenarios in which coexistence interference may happen, and then provides an overview of main solutions and related procedures specified in 3GPP Release-11 standards for LTE. In addition, some aspects of device-internal coordination and implementation to facilitate the coexistence scenarios are also discussed.

Distributed space-time block coding schemes based on quadrature amplitude modulation (QAM) symbols are introduced that enable users in a wireless multiple-access relay channel to cooperate with each other in order to improve the reliability of their information in a fair, rate-efficient manner. The distributed coding schemes are designed for a system that consists of m users that need to send their information to a common destination. Each user is equipped with only one antenna and a half-duplex transceiver so that it can transmit to the destination or any other user at one time and also receive signals from any other user at another time. The destination is equipped with one or more receive antennas. The goal is to design cooperative schemes which achieve the maximum diversity order (which is equal to the diversity order of the outage probability) while being fair to the users in terms of rate allocation. Two cooperative coding schemes are proposed that meet these requirements-a two-phase cooperative scheme and a single-phase self-information canceling linear (SCL) scheme. The two-phase scheme is of lower decoding complexity and it requires the users to only transmit QAM symbols. The SCL scheme is of higher complexity with the users transmitting linear combination of QAM symbols but it also achieves better performance. Both schemes incorporate new classes of cooperation rules for deciding whether or not a user acts as a relay for another user. The usual "outage-based" cooperation rule, whereby a user cooperates with another user provided the mutual information of the channel between them is greater than the rate, is sufficient for deriving information-theoretic limits but it cannot be used directly for analysis of a particular coding scheme. Even though the decoder used by the destination in the proposed coding schemes assumes that the inter-user communication is always successful, our performance analysis does not make this assumption. In fact, it rigorously accounts for the decoding errors arising from the information exchange between users. Consequently, it sheds light on precisely what cooperation rules (among the class of rules analyzed) lead to maximal diversity.

A unified framework for coherent multiple antenna communications is presented leading to a general space-time code design criterion valid for arbitrary spatial and temporal fading correlations. This framework provides insights into the effect of each of spatial and temporal correlations on space-time code design. The single code design expression applies to quasi-static, fast fading and multiple block fading channels and more generally also to channels with arbitrary correlations in the temporal dimension as well as in the spatial dimension with arbitrary rank. The general coding strategy proposed consists of precoding a space-time code with its size determined by the rank of transmit correlation, the structure determined by the Cholesky factorization of the temporal correlation, and the precoding matrix obtained from the eigenvectors of the transmit correlation matrix

A new approach is presented for the design of full modulation diversity (FMD) complex lattices for the Rayleigh-fading channel. The FMD lattice design problem essentially consists of maximizing a parameter called the normalized minimum product distance d/sub p//sup 2/ of the finite signal set carved out of the lattice. We approach the problem of maximizing d/sub p//sup 2/ by minimizing the average energy of the signal constellation obtained from a new family of FMD lattices. The unnormalized minimum product distance for every lattice in the proposed family is lower-bounded by a nonzero constant. Minimizing the average energy of the signal set translates to minimizing the Frobenius norm of the generator matrices within the proposed family. The two strategies proposed for the Frobenius norm reduction are based on the concepts of successive minima (SM) and basis reduction of an equivalent real lattice. The lattice constructions in this paper provide significantly larger normalized minimum product distances compared to the existing lattices in certain dimensions. The proposed construction is general and works for any dimension as long as a list of number fields of the same degree is available.

A space-time code is proposed that exhibits the highest coding gain among competing full-rate full transmit diversity space-time codes for the two transmit and receive antenna coherent quasi-static fading channel. The proposed code is derived from a layered architecture with real rotation of quadrature amplitude modulation (QAM) information symbols in two dimensions. The existing codes of similar architecture concentrate on application of complex full modulation diversity rotations or asymmetric real rotations. An analytic evaluation illustrates the significant improvement in coding gain achieved with the proposed code. Moreover, the coding gain of the proposed code is independent of its rate. This implies that the proposed code achieves the optimal diversity-multiplexing tradeoff curve for the two transmit antenna system. A stacked extension of the proposed code offers a reduced complexity capacity optimal alternative to the full diversity codes for larger number of transmit antennas. Performance enhancement in several scenarios is verified through simulations.

The design requirements for space-time coding typically involves achieving the goals of good performance, high rates, and low decoding complexity. In this paper, we introduce a further constraint on space-time code design in that the code should also lead to low values of the peak-to-mean envelope power ratio (PMEPR) for each antenna. Towards that end, we propose a new class of space-time codes called the "low PMEPR space-time" (LPST) codes. The LPST codes are obtained using the properties of certain cyclotomic number fields. The LPST codes achieve a performance identical to that of the threaded algebraic space-time (TAST) codes but at a much smaller PMEPR. With M antennas and a rate of one symbol per channel use, the LPST codes lead to a decrease in PMEPR by at least a factor of M relative to a Hadamard spread version of the TAST code. For rates beyond one symbol per channel use and up to a guaranteed amount, the LPST codes have provably smaller PMEPR than the corresponding TAST codes. Additionally, with the concept of punctured LPST codes proposed in this paper, significant performance improvement is obtained over the full diversity TAST schemes of comparable complexity. Numerical examples are provided to illustrate the advantage of the proposed codes in terms of PMEPR reduction and performance improvement for very high rate wireless communications.

We present the ALPS (Algorithms and Libraries for Physics Simulations) project, an international open source software project to develop libraries and application programs for the simulation of strongly correlated quantum lattice models such as quantum magnets, lattice bosons, and strongly correlated fermion systems. Development is centered on common XML and binary data formats, on libraries to simplify and speed up code development, and on full-featured simulation programs. The programs enable non-experts to start carrying out numerical simulations by providing basic implementations of the important algorithms for quantum lattice models: classical and quantum Monte Carlo (QMC) using non-local updates, extended ensemble simulations, exact and full diagonalization (ED), as well as the density matrix renormalization group (DMRG). The software is available from our web server at http://alps.comp-phys.org., For full software and introductory turorials see http://alps.comp-phys.org

Sacral osteomyelitis is a rare but potentially fatal complication of pelvic surgery. It is often diagnosed late due to the presence of vague, non-specific symptoms and a low index of suspicion. Previous literature has been limited to a number of case series of patients who have undergone ileoanal pouch formation following proctocolectomy and patients who have undergone pelvic floor reconstruction with mesh sacral colpopexy. Here, we present a patient presenting with sacral osteomyelitis 12 years following anterior resection for colorectal malignancy. We then review the previous literature and discuss the salient management points that may assist in the diagnosis and management of this uncommon complication.

A two user cooperation strategy based on QAM information symbols, known as the self-information canceling linear (SCL) scheme, was recently proposed by the authors. The SCL scheme achieves the full diversity order of 2 and the full multiplexing gain of 1 inherent in the system. However, the diversity versus multiplexing gain tradeoff (DMT) of the SCL scheme was not shown to be optimal. In the first part of this work, we propose a new two user cooperation strategy that achieves the optimal DMT curve for the two user cooperative diversity system. This scheme is obtained by a suitable modification of the original SCL scheme. The modified SCL scheme is also a practical cooperation strategy based on QAM information symbols and the present analysis accounts for the inter-user communications errors. The modified SCL scheme is, thus, established as a specific coding scheme to achieve the information theoretic limits within the DMT framework. In the second part of this work, we generalize the original SCL scheme to the case of m users for any m > 2. The generalization leads to a practical multiuser cooperative scheme based on QAM symbols that provides the full diversity order of m, fair rate allocation among the users and potential for achieving the full multiplexing gain.

Practical space-time coding strategies are proposed for multiple users cooperating to communicate to a destination in a wireless channel. For a system with m single antenna users and a destination with N receive antennas, a two-phase cooperative scheme is proposed that achieves a diversity order of m - 1 + N for the error probability. This effectively proves the achievability of the diversity order implied by the outage probability for this model. This two-phase scheme employs a short full diversity space-time block code over QAM symbols. Even though the suboptimum decoder used by the destination assumes that the inter-user communication is successful, the corresponding analysis does account for the decoding errors in the inter-user communications phase. The key to the diversity order analysis is an appropriate modification of the rule for deciding whether or not a user acts as a relay for another user. The performance analysis technique presented here also extends to another practical cooperation strategy, proposed specifically for the case of m = 2 and N = 1, that is inspired from an optimal diversity-multiplexing tradeoff curve achieving protocol.

We propose a design for a quantum bit with four superconducting islands in the topology of a symmetric tetrahedron, uniformly frustrated with one-half flux quantum per loop and one-half Cooper pair per island. This structure emulates a noise-resistant spin-1/2 system in a vanishing magnetic field. The tetrahedral quantum bit combines a number of advances such as a doubly degenerate ground state minimizing decoherence via phonon radiation, a weak quadratic sensitivity to electric and magnetic noise, relieved constraints on the junction fabrication, a large freedom in manipulation, and attractive measurement schemes. The simultaneous appearance of a degenerate ground state and a weak noise sensitivity are consequences of the tetrahedral symmetry, while enhanced quantum fluctuations derive from the special magnetic frustration. We determine the spectral properties of the tetrahedral structure within a semiclassical analysis and confirm the results numerically. We show how proper tuning of the charge frustration selects a doubly degenerate ground state and discuss the qubit's manipulation through capacitive and inductive coupling to external bias sources. The complete readout of the spin components sigma(i), i=x,y,z, is achieved through coupling of the internal qubit currents to external junctions driven close to criticality during the measurement.

A general class of training-based space-time codes is considered for the noncoherent block correlated Rayleigh fading channel. Such codes can be efficiently decoded by first forming the MMSE estimate of the channel and then decoding the underlying coherent space-time code using the channel estimate as if it were perfect. The diversity order of this (in general, suboptimal) estimator-decoder is obtained, and it is shown that under certain conditions on the channel correlation matrix, training codes inherit the diversity order of the underlying coherent code.

A space-time code is proposed that exhibits the highest coding gain between competing full rate full transmit diversity space-time codes for the two transmit antenna wireless channel. The proposed code is derived from a layered architecture with real rotation of QAM information symbols in two dimensions. The existing codes of similar architecture concentrate on application of complex full modulation diversity rotations or asymmetric real rotations for the two layers. An analytic evaluation illustrates the significant improvement in coding gain achieved with the proposed code. Moreover, the value of the unnormalized coding gain for the new code is independent of the rate of the code. A stacked extension of the proposed code offers a reduced complexity capacity optimal alternative to the full diversity codes for larger number of transmit antennas. Performance enhancement in several scenarios is verified through simulations.

A new class of full diversity space-time codes is proposed that leads to a significantly smaller peak-to-mean envelope power ratio (PMEPR) compared to the recently invented diagonal algebraic space-time (DAST) and threaded algebraic space-time (TAST) codes. Moreover, the proposed "low PMEPR space-time" (LPST) codes exhibit identical performance and decoding complexity compared to the TAST codes. Additionally, unlike the TAST codes, the LPST codes meet an upper bound known as the singleton bound on the maximum achievable rate by a space-time code. The key to the construction of the LPST codes is an improved spreading scheme that outperforms the originally suggested Hadamard spreading scheme for the PMEPR reduction of DAST codes. Several properties of the LPST codes in relation to PMEPR are studied. Numerical results are presented to support the significant advantage of the proposed codes in terms of reduced PMEPR for high rate wireless communications.

Monte Carlo methods are well-suited for the simulation of large many body problems, since the complexity for a single Monte Carlo update step scales only polynomially and often linearly in the system size, while the config- uration space grows exponentially with the system size. The performance of a Monte Carlo method is then deter- mined by how many update steps are needed to efficiently sample the configuration space. For second order phase transitions in unfrustrated systems the problem of "crit- ical slowing down" - a rapid divergence of the number of Monte Carlo steps needed to obtain a subsequent un- correlated configuration - was solved more than a decade ago by cluster update algorithms (1). At first order phase transitions and in systems with many local minima of the free energy such as frustrated magnets or spin glasses, there is the similar problem of long tunneling times be- tween local minima. With energy barriersE scaling lin- early with the linear system size L, the tunneling times � at an inverse temperature � = 1/kBT scale exponentially with the system size, � � exp(��E) / exp(const × L). Several methods were developed to overcome this tun- neling problem, such as the multicanonical method (2), broad histograms (4), simulated and parallel tempering (3), and Wang-Landau sampling (5). The common aim of all these methods is to broaden the range of energies sam- pled within Monte Carlo simulations from the sharply peaked distribution of canonical sampling at fixed tem- perature in order to ease the tunneling through barriers. Ideally, all relevant energy levels are sampled equally often during a simulation, thus producing a "flat his- togram" in energy space. Some methods approach this goal by variations and generalizations of canonical dis- tributions (2, 3), while others (4, 5) discard the notion of temperature completely and instead are formulated in terms of the density of states. With a probability p(E) for a single configuration with energy E, the probability of sampling an arbitrary configuration with energy E is given as PE = �(E)p(E), where the density of states �(E) counts the number of states with energy E. Upon choos- ing p(E) / 1/�(E) instead of p(E) / exp( �E) one ob- tains a constant probability PE for visiting each energy level E, and hence a flat histogram. Wang and Landau (5) proposed a simple and elegant flat histogram algorithm that iteratively improves approximations to the initially unknown density of states �(E). Once �(E) is determined with sufficient accuracy, the Monte Carlo algorithm just performs a random walk in energy space. Within two years of publication this algorithm has been applied to a large number of problems (6, 7, 8) and extended to quantum systems (9). In this Letter we investigate the performance of flat histogram algorithms in general, and the Wang-Landau algorithm in particular, for three systems for which the density of states �(E) is known exactly on finite two- dimensional (2D) lattices: the Ising ferromagnet as the simplest example, the fully frustrated Ising model as a prototype for frustrated systems, and the ±J Ising spin glass. For each of these models we construct a perfect flat histogram method by simulating a random walk in configuration space where we employ the known density of states for these models to set p(E) / 1/�(E). As a measure of performance we use the average tun- neling timeto get from a ground state (lowest energy configuration) to an anti-ground state (configuration of highest energy), which is the relevant time scale for sam- pling the whole phase space (10). Since the number of energy levels in a d-dimensional system with linear size L scales with the number of spins N = L d , the tunneling time for a pure random walk in energy space is

In 31 patients of myelodysplastic syndrome, RAEB-t was the commonest subtype (29%), and RARS, the lease common (6.4%); 19.4% were characterised as the unclassifiable (UC) group. Pallor was the dominant sign (90.3%). Low haemoglobin in RARARS (p0.05), thrombocytopenia in RAEB-t (p0.01) and high leuco/monocyte counts in CMML (p0.001) were observed. Neutropenia occurred most frequently in RAEBRAEB-t and circulating blasts in all cases of RAEB-t and CMML. Bicytopenia was the commonest finding (58.1%) and pancytopenia the least (16.1%). 84% of marrows were hypercellular and trilineage dysplasia was seen in 68% of patients. Megaloblastoid dyserythropoiesis was the predominant feature in all cases, dysgranulopoiesis in all cases of RAEB, RAEB-t and CMML, and micromegokaryocytes in all cases of RARS, RAEBCMML were seen. RAEB-t and RAEB (33.3% each) were the predominant groups which progressed to leukemia, FAB AML-M2, being the commonest type (60%).

Sturge-Weber syndrome is reported in a 19 year old male. Intraoral manifestations of SWS are uncommon. Hence, the present case is reported for the presence of gingival capillary hemangioma which was surgically treated. A review from the literature pertaining to orofacial manifestations of SWS is given.

In the opinion of the author, C.A.T. though an excellent technique has very limited use in India, partly, because of the extensive aural pathology met with and partly because of limited scope of follow-up. Canal plasty can be carried out with cartilage, bone chips or teflon sheetings with equally good results even after taking down the bridge for thorough elimination of disease.

Dislocation of foot plate partial or complete is definitely a problem in stapes surgery. Methods to prevent dislocation have have been suggested. Proper appreciation of vestibular anatomy is necessary in order to plan safe removal of a dislocated foot plate. Each case presents its own problems and has to be treated as such, as is evident from the cases described above. A sunk foot plate is best left alone if it is not possible to refloat it. It does not always result in a dead ear.

We determine the optimal scaling of local‐update flat‐histogram methods (such as multicanonical, broad histograms, tempering, or Wang‐Landau sampling) with system size by using a perfect flat‐histogram scheme based on the exact density of states of 2D Ising models. We find that the Wang‐Landau algorithm shows the same scaling as the perfect scheme and is thus optimal. However, even for the perfect scheme the scaling with the number of spins N is slower than the minimal N2 of an unbiased random walk in energy space for both, local and N‐fold way updates. While it still follows a power law N2Lz for the ferromagnetic and fully frustrated Ising model we find exponential scaling of the tunneling times in the case of the ±J Ising spin glass. The tunneling times of the ±J Ising spin glass are found to follow a fat‐tailed Frechet extremal value distribution.