Evidence of a Hardening in the Cosmic Ray Proton Spectrum at around 166 TeV Observed by the GRAPES-3 Experiment

We present the measurement of the cosmic ray proton spectrum from 50 TeV to 1.3 PeV using 7.81×10^{6} extensive air shower events recorded by the ground-based GRAPES-3 experiment between 1 January 2014 and 26 October 2015 with a live time of 460 day. Our measurements provide an overlap with direct observations by satellite and balloon-based experiments. The electromagnetic and muon components in the shower were measured by a dense array of plastic scintillator detectors and a tracking muon telescope, respectively. The relative composition of the proton primary from the air shower data containing all primary particles was extracted using the multiplicity distribution of muons which is a sensitive observable for mass composition. The observed proton spectrum suggests a spectral hardening at ∼166  TeV and disfavors a single power law description of the spectrum up to the Knee energy (∼3  PeV).

Comparison of Ultrasound-Guided Umbilical Venous Catheter Insertion with Blind Method: A Randomized Controlled Trial

Introduction

Ultrasonography (USG) can be used in neonates to manipulate and place the umbilical catheter in the correct position. Although chest radiograph (CXR) is the gold standard, a noninvasive method like USG without radiation exposure may be an alternative bedside armamentarium to the clinician. The purpose of the study was to evaluate whether USG-guided umbilical venous catheter (UVC) insertion is superior to the conventional method for the successful insertion of UVC.

Method

The neonates born between 25 and 42 weeks of gestation requiring parenteral fluids and admission to neonatal intensive care unit (NICU) between September 2020 and November 2022 were randomized in two weight-based strata: ≤1,200 and >1,200 g. USG-guided UVC insertion was done in the intervention group and blind UVC insertion was done in the control group.

Results

Out of 112 enrolled neonates, 58 were in the USG-guided group and 54 in the blind group. There was no significant difference in the failure rate between the intervention and control groups (20% versus 29% [RR: 0.69, 95% CI: 0.36-1.33]). The sensitivity and specificity of USG in locating tip position were 97 and 46.8%, respectively. The mean procedure time in USG and blind groups was 8.9 and 8.3 min, respectively (p value 0.56).

Conclusion

USG does not reduce the failure rates during the insertion of umbilical catheters. However, being a safe, noninvasive procedure, it can be considered a rescue modality to CXR in NICUs equipped with portable USG for guiding UVC insertion.

Routine third trimester ultrasonography in predicting adverse perinatal outcomes: a prospective cohort study at a tertiary-care hospital in Eastern India

AIMS

Fetal growth restriction (FGR) may go undetected in the antenatal period with subjective clinical evaluation, and there is a growing propensity to perform a third-trimester scan, especially in the developed countries. The literature on the importance of the same in developing countries like ours, is scant. Hence, this study was undertaken to evaluate the role of routine third-trimester ultrasonography along with Doppler in predicting adverse perinatal outcome.

METHODS

A prospective cohort study was conducted at a tertiary-care hospital, in which routine third-trimester ultrasonography was performed for 265 antenatal women, and included estimation of amniotic fluid index (AFI), estimated fetal-weight (EFW), and cerebroplacental ratio (CPR). Women were categorized as having normal parameters or having at least one abnormal parameter. Post-natal adverse perinatal outcomes including low birth-weight, hypoglycemia, poor Apgar scores, prolonged hospital stay, need for ventilatory support, neonatal asphyxia, neonatal sepsis and early neonatal death were recorded. Prediction analyses for sensitivity, specificity, positive and negative predictive values were done. Receiver Operating Characteristic (ROC) curves were plotted for threshold for each parameter for adverse outcome.

RESULTS

Out of 260 women that were analyzed, 47.5% had no clinically identifiable risk factors, and 52.5% had at least one abnormal parameter. Sensitivity and negative predictive value for adverse outcome were highest for composite ultrasound finding (85.4% and 90.4% respectively). Specificity, positive predictive value and diagnostic accuracy were highest for CPR (97.8%, 86.7% and 76.9% respectively).

CONCLUSION

Routine third trimester ultrasonography, including Doppler, can help in risk-stratification of otherwise clinically low-risk pregnancies.

Impact of a quality improvement program: Early initiation of breastfeeding after cesarean section in a tertiary care hospital, in Eastern India

Background

Early initiation of breastfeeding (EIBF) within 1 h of birth is crucial in preventing newborn deaths and plays a vital role in early infant nutrition. Promoting and supporting breastfeeding is an integral part of midwifery. The objective of the study was to improve the EIBF rate in neonates born through a Cesarean Section (CS) from 0% to 50% within six months through a quality improvement (QI) process and to assess the maternal experience of EIBF in operation theatre (OT).

Methods

Six Plan-Do-Study-Act (PDSA) cycles were conducted to test the change ideas proposed by the team members for a month to improve EIBF. Participants of the study were the stable term newborns delivered by CS under spinal anesthesia.

Results

The EIBF rate improved from 0% to 88% after the sixth PDSA cycle. The effect was sustained for six months. Mothers of 51 neonates (98%) who received EIBF reported that their newborns were breastfed successfully, and it was not physically tiring to feed immediately in the OT.

Conclusions

A quality improvement (QI) initiative was able to improve and sustain the improved EIBF rate after CS. Early skin-to-skin contact to be initiated with EIBF for better neonatal outcomes.

Many universality classes in an interface model restricted to non-negative heights

We present a simple one-dimensional stochastic model with three control parameters and a surprisingly rich zoo of phase transitions. At each (discrete) site x and time t, an integer n(x,t) satisfies a linear interface equation with added random noise. Depending on the control parameters, this noise may or may not satisfy the detailed balance condition, so that the growing interfaces are in the Edwards-Wilkinson or in the Kardar-Parisi-Zhang universality class. In addition, there is also a constraint n(x,t)≥0. Points x where n>0 on one side and n=0 on the other are called "fronts." These fronts can be "pushed" or "pulled," depending on the control parameters. For pulled fronts, the lateral spreading is in the directed percolation (DP) universality class, while it is in a different universality class for pushed fronts, and another universality class in between. In the DP case, the activity at each active site can in general be arbitrarily large, in contrast to previous realizations of DP. Finally, we find two different types of transitions when the interface detaches from the line n=0 (with 〈n(x,t)〉→const on one side, and →∞ on the other), again with new universality classes. We also discuss a mapping of this model to the avalanche propagation in a directed Oslo rice pile model in specially prepared backgrounds.

Congenital Acinar Cystic Transformation of the Pancreas with Proximal Jejunal Atresia and Hepatic Iron Overload: An Autopsy Case

Introduction: Acinar cystic transformation (ACT) of the pancreas is characterized by multiple cysts lined by dual ductal and acinar-type of epithelium. ACT is typically a disease of adulthood and has not been described in a neonate. Case report: Autopsy of this term 3-day old male demonstrated cystic transformation of the entire pancreas measuring 42 mm in its largest dimension. The main pancreatic duct was patent. The numerous variable-sized cysts were lined by both ductal (CK7-positive) and acinar (trypsin-positive) epithelium. Congenital hemochromatosis of the liver, complete proximal jejunal atresia, gangrene of the post-atretic jejunum, and subglottic stenosis were associated features. Discussion/Conclusion: ACT may occur in the neonate in association with other abnormalities.

Determinants of ERP Adoption, User Satisfaction, and User Engagement

Based on the theory of reasoned action (TRA) and the diffusion of innovation framework, this study examines the key determinants and outcomes of enterprise resource planning (ERP) adoption. The study specifically investigated the impact of system quality and user training on ERP adoption intention. Further, the impacts of ERP adoption intention and personal innovativeness on ERP adoption were also studied. User satisfaction with ERP and user engagement were considered as the two outcomes of ERP adoption. To achieve these objectives, an online survey was conducted and data was collected from 180 ERP users across multiple industries in India to understand their perception of such matters. Structural equation modeling using the partial least square approach was used to test the proposed hypotheses. The results of SEM analysis supported all the hypotheses under investigation. These results provide relevant evidence that may encourage organizations to understand the key determinants of successful ERP adoption and its significant impacts on user satisfaction with ERP and user engagement.

Intestinal Failure in a Neonate: A Surgical Emergency and Medical Catastrophe

In this case report, we present a female neonate referred to us, born to a primigravida mother at 39 weeks, who cried after birth, did not require any resuscitation, had a birth weight of 2.9 kg and developed abdominal distension and bilious vomiting on Day 1 of life. Ultrasound abdomen and X-ray imaging were suggestive of midgut volvulus with malrotation. The emergency explorative laparotomy revealed the small bowel to be gangrenous in extensive areas, and 10 cm of the small intestine was successfully preserved. The baby was admitted to the NICU and required three months of total parenteral nutrition. In between, the baby was managed successfully for sepsis, septic shock, diarrhea, and dehydration, Later, she was discharged, and is currently being followed up. At the first follow-up, the baby was noted to be gaining weight and has developed no complications to date.

Clinical Profile and Risk Factors for Severe Disease in 402 Children Hospitalized with SARS-CoV-2 from India: Collaborative Indian Pediatric COVID Study Group

INTRODUCTION

There is a lack of large multicentric studies in children with COVID-19 from developing countries. We aimed to describe the clinical profile and risk factors for severe disease in children hospitalized with COVID-19 from India.

METHODS

In this multicentric retrospective study, we retrieved data related to demographic details, clinical features, including the severity of disease, laboratory investigations and outcome.

RESULTS

We included 402 children with a median (IQR) age of 7 (2-11) years. Fever was the most common symptom, present in 38.2% of children. About 44% had underlying comorbidity. The majority were asymptomatic (144, 35.8%) or mildly symptomatic (219, 54.5%). There were 39 (9.7%) moderate-severe cases and 13 (3.2%) deaths. The laboratory abnormalities included lymphopenia 25.4%, thrombocytopenia 22.1%, transaminitis 26.4%, low total serum protein 34.7%, low serum albumin 37.9% and low alkaline phosphatase 40%. Out of those who were tested, raised inflammatory markers were ferritin 58.9% (56/95), c-reactive protein 33.3% (41/123), procalcitonin 53.5% (46/86) and interleukin-6 (IL-6) 76%. The presence of fever, rash, vomiting, underlying comorbidity, increased total leucocyte count, thrombocytopenia, high urea, low total serum protein and raised c-reactive protein was factors associated with moderate to severe disease.

CONCLUSION

Fever was the commonest symptom. We identified additional laboratory abnormalities, namely lymphopenia, low total serum protein and albumin and low alkaline phosphatase. The majority of the children were asymptomatic or mildly symptomatic. We found high urea and low total serum protein as risk factors for moderate to severe disease for the first time.

Congenital ichthyosiform erythroderma: A rare neonatal dermatoses responding to acitretin

Congenital ichthyosiform erythroderma is a rare and severe form of ichthyosis manifesting in the neonatal age group. We report a child with diffuse peeling of skin and erythroderma presenting on the 2^nd day of birth. With aseptic nursing care along with emollients and oral acitretin, the child's quality of life improved remarkably, hence highlighting the point of early and judicious use of acitretin in reducing disease morbidity.

Measurement of the Electrical Properties of a Thundercloud Through Muon Imaging by the GRAPES-3 Experiment

The GRAPES-3 muon telescope located in Ooty, India records rapid (∼10  min) variations in the muon intensity during major thunderstorms. Out of a total of 184 thunderstorms recorded during the interval of April 2011-December 2014, the one on December 1, 2014 produced a massive potential of 1.3 GV. The electric field measured by four well-separated (up to 6 km) monitors on the ground was used to help estimate some of the properties of this thundercloud, including its altitude and area that were found to be 11.4 km above mean sea level and ≥380  km^{2}, respectively. A charging time of 6 min to reach 1.3 GV implied the delivery of a power of ≥2  GW by this thundercloud that was moving at a speed of ∼60  km h^{-1}. This work possibly provides the first direct evidence for the generation of gigavolt potentials in thunderclouds that could also possibly explain the production of highest-energy (100 MeV) gamma rays in the terrestrial gamma-ray flashes.

Difficult intubation in a neonate: a diagnostic dilemma

Difficult intubation in neonates has innumerable aetiologies. It especially poses a formidable challenge to save a newborn baby immediately after birth where antenatal details are unavailable. A late preterm neonate was born limp and apnoeic. Several attempts to intubate the baby were unsuccessful. Possibility of subglottic obstruction was considered. The baby died of severe perinatal asphyxia. Autopsy showed a mass around the airway which turned out to be ectopic thymus on histopathology. Ectopic thymus can present as periglottic mass without externally visible cervical swelling and can cause difficult intubation which may lead to serious adverse outcome including death if not anticipated early and managed accordingly.

Negative differential mobility in interacting particle systems

Driven particles in the presence of crowded environment, obstacles, or kinetic constraints often exhibit negative differential mobility (NDM) due to their decreased dynamical activity. Based on the empirical studies of conserved lattice gas model, two species exclusion model and other interacting particle systems we propose a new mechanism for complex many-particle systems where slowing down of certain non-driven degrees of freedom by the external field can give rise to NDM. To prove that the slowing down of the non-driven degrees is indeed the underlying cause, we consider several driven diffusive systems including two species exclusion models, misanthrope process, and show from the exact steady state results that NDM indeed appears when some non-driven modes are slowed down deliberately. For clarity, we also provide a simple pedagogical example of two interacting random walkers on a ring which conforms to the proposed scenario.

Multichain models of conserved lattice gas

Conserved lattice-gas models in one dimension exhibit absorbing state phase transition (APT) with simple integer exponents β=1=ν=η, whereas the same on a ladder belong to directed percolation (DP) universality. We conjecture that additional stochasticity in particle transfer is a relevant perturbation and its presence on a ladder forces the APT to be in the DP class. To substantiate this we introduce a class of restricted conserved lattice-gas models on a multichain system (M×L square lattice with periodic boundary condition in both directions), where particles which have exactly one vacant neighbor are active and they move deterministically to the neighboring vacant site. We show that for odd number of chains, in the thermodynamic limit L→∞, these models exhibit APT at ρ_{c}=1/2(1+1/M) with β=1. On the other hand, for even-chain systems transition occurs at ρ_{c}=1/2 with β=1,2 for M=2,4, respectively, and β=3 for M≥6. We illustrate this unusual critical behavior analytically using a transfer-matrix method.

Continuously Varying Critical Exponents Beyond Weak Universality

Renormalization group theory does not restrict the form of continuous variation of critical exponents which occurs in presence of a marginal operator. However, the continuous variation of critical exponents, observed in different contexts, usually follows a weak universality scenario where some of the exponents (e.g., β, γ, ν) vary keeping others (e.g., δ, η) fixed. Here we report ferromagnetic phase transition in (Sm_1−yNd_y)_0.52Sr_0.48MnO₃ (0.5 ≤ y ≤ 1) single crystals where all three exponents β, γ, δ vary with Nd concentration y. Such a variation clearly violates both universality and weak universality hypothesis. We propose a new scaling theory that explains the present experimental results, reduces to the weak universality as a special case, and provides a generic route leading to continuous variation of critical exponents and multi-criticality.

Multicritical absorbing phase transition in a class of exactly solvable models

We study diffusion of hard-core particles on a one-dimensional periodic lattice subjected to a constraint that the separation between any two consecutive particles does not increase beyond a fixed value n+1; an initial separation larger than n+1 can however decrease. These models undergo an absorbing state phase transition when the conserved particle density of the system falls below a critical threshold ρ_{c}=1/(n+1). We find that the ϕ_{k}, the density of 0-clusters (0 representing vacancies) of size 0≤k<n, vanish at the transition point along with activity density ρ_{a}. The steady state of these models can be written in matrix product form to obtain analytically the static exponents β_{k}=n-k and ν=1=η corresponding to each ϕ_{k}. We also show from numerical simulations that, starting from a natural condition, ϕ_{k}(t)s decay as t^{-α_{k}} with α_{k}=(n-k)/2 even though other dynamic exponents ν_{t}=2=z are independent of k; this ensures the validity of scaling laws β=αν_{t} and ν_{t}=zν.

Transient Weakening of Earth's Magnetic Shield Probed by a Cosmic Ray Burst

The GRAPES-3 tracking muon telescope in Ooty, India measures muon intensity at high cutoff rigidities (15-24 GV) along nine independent directions covering 2.3 sr. The arrival of a coronal mass ejection on 22 June 2015 18:40 UT had triggered a severe G4-class geomagnetic storm (storm). Starting 19:00 UT, the GRAPES-3 muon telescope recorded a 2 h high-energy (∼20  GeV) burst of galactic cosmic rays (GCRs) that was strongly correlated with a 40 nT surge in the interplanetary magnetic field (IMF). Simulations have shown that a large (17×) compression of the IMF to 680 nT, followed by reconnection with the geomagnetic field (GMF) leading to lower cutoff rigidities could generate this burst. Here, 680 nT represents a short-term change in GMF around Earth, averaged over 7 times its volume. The GCRs, due to lowering of cutoff rigidities, were deflected from Earth's day side by ∼210° in longitude, offering a natural explanation of its night-time detection by the GRAPES-3. The simultaneous occurrence of the burst in all nine directions suggests its origin close to Earth. It also indicates a transient weakening of Earth's magnetic shield, and may hold clues for a better understanding of future superstorms that could cripple modern technological infrastructure on Earth, and endanger the lives of the astronauts in space.

Substance abuse in Heart Transplant Recipients: A 10-Year Follow-up Study

Context—

Active substance abuse is widely accepted as a contraindication for heart transplantation because of the theory that relapse would occur after transplantation and result in compromise of graft function, lowering long-term survival. Listing “recovering” substance abusers for heart transplantation has been controversial.

Objective—

To determine if substance abuse plays an unfavorable role in the outcome of heart transplantation.

Methods—

The medical records of all patients at our center who received a heart transplant more than 10 years ago were retrospectively reviewed for history of substance abuse.

Results—

From a pool of 189 transplant recipients, 47 patients had a definite history of substance abuse (group 1) and were considered in recovery, whereas 142 patients were clearly without any history of substance abuse (group 2). Group 1 had a significantly greater percentage of patients with a pretransplantation diagnosis of idiopathic cardiomyopathy ( P=.003), a higher occurrence of heart-related cause of death ( P=.017), and a significant prevalence of noncompliance ( P=.0001) and death because of noncompliance ( P=.0004). In contrast, group 2 surprisingly had a significantly higher incidence of death related to infection ( P=.0062), which is unexplained. Despite higher incidence of noncompliance in group 1, there was no significant difference in the overall survival rate between the 2 groups.

Conclusion—

These results suggest that patients with a history of substance abuse can undergo successful heart transplantation with acceptable long-term survival, though they are at greater risk for substance abuse relapse and resulting noncompliance with the treatment regimen. The extent to which relapse of substance abuse and its consequences affect the cost of posttransplantation care remains to be determined.

Oslo model, hyperuniformity, and the quenched Edwards-Wilkinson model

We present simulations of the one-dimensional Oslo rice pile model in which the critical height at each site is randomly reset after each toppling. We use the fact that the stationary state of this sand-pile model is hyperuniform to reach system of sizes >10^{7}. Most previous simulations were seriously flawed by important finite-size corrections. We find that all critical exponents have values consistent with simple rationals: ν=4/3 for the correlation length exponent, D=9/4 for the fractal dimension of avalanche clusters, and z=10/7 for the dynamical exponent. In addition, we relate the hyperuniformity exponent to the correlation length exponent ν. Finally, we discuss the relationship with the quenched Edwards-Wilkinson model, where we find in particular that the local roughness exponent is α_{loc}=1.

Morbidities in Neonates Delivered Electively at Early Term

OBJECTIVE

To study the incidence of elective cesarean deliveries at term and to correlate their neonatal outcomes at different gestational ages (37(0/7)-40(6/7)).

METHODS

Outcomes including the rate of NICU admissions, usage of ventilator/CPAP, and other morbidities were analysed and compared with the gestational age during the study period from January 2012 to April 2013.

RESULTS

The incidences of elective deliveries at 37, 38, 39, and 40 weeks of gestation were 10.6, 29.7, 28, and 31.5 %, respectively. NICU admissions-RR 3.94 (95 % CI 1.92-8.09), respiratory distress-RR 5.255 (95 % CI 1.9-14.4), ventilatory usage, and hospitalization stay (P value < 0.05) were higher in neonates born at 37(0/7-6/7) versus 39(0/7-6/7) weeks (least morbidity group).

CONCLUSION

Despite recommendations, more than one-third of term babies are delivered electively at <39 weeks. The fivefold augmented respiratory morbidity and fourfold increased NICU admissions in early term neonates, and the least morbidity in neonates delivered at 39 weeks emphasize the importance of restricting the non-emergent/elective deliveries to 39 weeks of gestation.

Phase coexistence and spatial correlations in reconstituting k-mer models

In reconstituting k-mer models, extended objects that occupy several sites on a one-dimensional lattice undergo directed or undirected diffusion, and reconstitute-when in contact-by transferring a single monomer unit from one k-mer to the other; the rates depend on the size of participating k-mers. This polydispersed system has two conserved quantities, the number of k-mers and the packing fraction. We provide a matrix product method to write the steady state of this model and to calculate the spatial correlation functions analytically. We show that for a constant reconstitution rate, the spatial correlation exhibits damped oscillations in some density regions separated, from other regions with exponential decay, by a disorder surface. In a specific limit, this constant-rate reconstitution model is equivalent to a single dimer model and exhibits a phase coexistence similar to the one observed earlier in totally asymmetric simple exclusion process on a ring with a defect.

Oral Paracetamol for Closure of Patent Ductus Arteriosus in Selected Preterm Neonates

We prospectively studied the effect of oral paracetamol in closing hemodynamically significant Patent ductus arteriosus in preterm infants (gestational age <32 weeks) where Ibuprofen was contraindicated. 29 of 40 neonates (72.5%) showed successful response while 11 (29.5%) failed to show any response. No major complications were seen.

Additivity property and emergence of power laws in nonequilibrium steady states

We show that an equilibriumlike additivity property can remarkably lead to power-law distributions observed frequently in a wide class of out-of-equilibrium systems. The additivity property can determine the full scaling form of the distribution functions and the associated exponents. The asymptotic behavior of these distributions is solely governed by branch-cut singularity in the variance of subsystem mass. To substantiate these claims, we explicitly calculate, using the additivity property, subsystem mass distributions in a wide class of previously studied mass aggregation models as well as in their variants. These results could help in the thermodynamic characterization of nonequilibrium critical phenomena.

Cluster-factorized steady states in finite-range processes

We study a class of nonequilibrium lattice models on a ring where particles hop in a particular direction, from a site to one of its (say, right) nearest neighbors, with a rate that depends on the occupation of all the neighboring sites within a range R. This finite-range process (FRP) for R=0 reduces to the well-known zero-range process (ZRP), giving rise to a factorized steady state (FSS) for any arbitrary hop rate. We show that, provided the hop rates satisfy a specific condition, the steady state of FRP can be written as a product of a cluster-weight function of (R+1) occupation variables. We show that, for a large class of cluster-weight functions, the cluster-factorized steady state admits a finite dimensional transfer-matrix formulation, which helps in calculating the spatial correlation functions and subsystem mass distributions exactly. We also discuss a criterion for which the FRP undergoes a condensation transition.

Zeroth law and nonequilibrium thermodynamics for steady states in contact

We ask what happens when two nonequilibrium systems in steady state are kept in contact and allowed to exchange a quantity, say mass, which is conserved in the combined system. Will the systems eventually evolve to a new stationary state where a certain intensive thermodynamic variable, like equilibrium chemical potential, equalizes following the zeroth law of thermodynamics and, if so, under what conditions is it possible? We argue that an equilibriumlike thermodynamic structure can be extended to nonequilibrium steady states having short-ranged spatial correlations, provided that the systems interact weakly to exchange mass with rates satisfying a balance condition-reminiscent of a detailed balance condition in equilibrium. The short-ranged correlations would lead to subsystem factorization on a coarse-grained level and the balance condition ensures both equalization of an intensive thermodynamic variable as well as ensemble equivalence, which are crucial for construction of a well-defined nonequilibrium thermodynamics. This proposition is proved and demonstrated in various conserved-mass transport processes having nonzero spatial correlations.

Cardiac tamponade in a neonate: a dreadful condition--need for functional echo

Cardiac tamponade is a clinical emergency. Detection of a swinging heart rate is one of the earliest markers of large pericardial effusion, in which the four cardiac chambers are free to float in a phasic manner. We present a case of a preterm baby, one of the twins, who developed sudden onset of deterioration in the form of swinging heart rate, fluctuation in blood pressure and desaturation, requiring emergency intubation and inotropic support. Bedside functional echo was performed, which demonstrated cardiac tamponade; an immediate echocardiography-guided tap was initiated and fluid was aspirated from the pericardial space.

Anteromedial pneumothorax in a neonate: 'the diagnostic dilemma' and the importance of clinical signs

A premature neonate born at 32 weeks of gestation was admitted to the neonatal unit with respiratory distress syndrome. The infant received late rescue surfactant therapy with continued mechanical ventilation in view of continuous positive airway pressure (CPAP) failure. Owing to worsening distress and an air leak, he was switched over to high-frequency oscillatory ventilation. The air leak required drainage for possible pneumopericardium. This was initially attempted ineffectually with echo-assisted pericardial drainage, and later successfully with the use of chest tubes for anteromedial pneumothorax.

Primary spontaneous bilateral pneumothorax in a neonate

Pneumothorax, though rare, is a recognized cause of respiratory distress in the immediate newborn period. It may occur spontaneously or secondary to various underlying lung diseases. Here we share our experience of a neonate with spontaneous pneumothorax with mild to moderate respiratory distress, who recovered completely with conservative management with an oxygen-enriched atmosphere and no surgical intervention.

Repair of oral mucosal defects with cryopreserved human amniotic membrane grafts: prospective clinical study

The aim of this study was to evaluate the clinical outcome of the surgical repair of oral mucosal defects using cryopreserved human amniotic membrane (HAM) as a graft material. Thirty-four patients with precancerous lesions such as leukoplakia, erythroplakia, and verrucous hyperplasia were included. Fresh amniotic membrane was obtained from women undergoing elective caesarean section; the membrane was cleaned, prepared in antibiotic solutions, and preserved at -80°C. Results suggested that HAM promotes healing and epithelialization without specific complications. Thus we conclude that the use of HAM gives promising results in the repair of post-surgical oral mucosal defects.

Neonatal intestinal obstruction secondary to a small bowel duplication cyst

A 3-week-old neonate developed abdominal distension and vomiting which subsided after conservative management. However, there was a recurrence of symptoms for which a lower gastrointestinal tract contrast study was performed. The infant had a filling defect in the area of the transverse colon. A CT scan was performed, showing a duplication cyst arising from the small bowel and indenting the transverse colon. Resection of the duplication cyst and end-to-end anastomosis of the bowel was performed. The duplication cyst was of tubular type, and a sealed perforation was noted in the cyst wall.

Perinatal neuroblastoma: a hidden bullet in the chest

A neonate with antenatally diagnosed intrathoracic mass by ultrasound scan was delivered uneventfully at 35 weeks gestation by caesarean section due to pre-eclampsia and fluctuating hypertension in the mother. The intrathoracic mass was echogenic and the diagnosis was inconclusive. At 12 h of life the baby deteriorated acutely, in terms of increased oxygen requirement, ventilatory care, heart rate fluctuation, hypotension requiring inotropic support and died despite intensive care support. The parents were counselled that an autopsy would be invaluable in providing a diagnosis given the antenatal finding of an intrathoracic mass. The final diagnosis of neuroblastoma was performed at postmortem.

Gammalike mass distributions and mass fluctuations in conserved-mass transport processes

We show that, in conserved-mass transport processes, the steady-state distribution of mass in a subsystem is uniquely determined from the functional dependence of variance of the subsystem mass on its mean, provided that the joint mass distribution of subsystems is factorized in the thermodynamic limit. The factorization condition is not too restrictive as it would hold in systems with short-ranged spatial correlations. To demonstrate the result, we revisit a broad class of mass transport models and its generic variants, and show that the variance of the subsystem mass in these models is proportional to the square of its mean. This particular functional form of the variance constrains the subsystem mass distribution to be a gamma distribution irrespective of the dynamical rules.

Diagnostic dilemma: Kikuchi's disease or tuberculosis?

Any patient from a tuberculosis (TB) endemic area such as India with classical clinical features of fever, weight loss and lymphadenopathy, making a diagnosis of Kikuchi's disease (KD) prior to waiting for the 6-week culture is not appropriate. KD or histiocytic necrotising lymphadenitis is a rare self-limiting cervical lymphadenitis, often a diagnosis of exclusion. One needs to exclude TB, sarcodosis, lymphoma and autoimmune diseases to make such a diagnosis. The patient here with classical clinical presentation of TB with lymph node biopsy mimicking KD (biopsy and immunohistochemistry) posed a big diagnostic dilemma. However, culture of the biopsied lymphatic tissue was confirmed to be mycobacterium TB after the 6th week of incubation. The patient was treated with antitubercular drugs initially, and later, steroid was added in view of his persistent symptoms and he responded. One should wait for the tissue culture report to confirm or exclude the diagnosis of TB. Exclusion should not be based only on laboratory criteria. Histopathogically, TB can mimic any other granulomatous disorder.

Fixed-energy sandpiles belong generically to directed percolation

Fixed-energy sandpiles with stochastic update rules are known to exhibit a nonequilibrium phase transition from an active phase into infinitely many absorbing states. Examples include the conserved Manna model, the conserved lattice gas, and the conserved threshold transfer process. It is believed that the transitions in these models belong to an autonomous universality class of nonequilibrium phase transitions, the so-called Manna class. Contrarily, the present numerical study of selected (1+1)-dimensional models in this class suggests that their critical behavior converges to directed percolation after very long time, questioning the existence of an independent Manna class.

Monte Carlo code G3sim for simulation of plastic scintillator detectors with wavelength shifter fiber readout

A detailed description of a compact Monte Carlo simulation code "G3sim" for studying the performance of a plastic scintillator detector with wavelength shifter (WLS) fiber readout is presented. G3sim was developed for optimizing the design of new scintillator detectors used in the GRAPES-3 extensive air shower experiment. Propagation of the blue photons produced by the passage of relativistic charged particles in the scintillator is treated by incorporating the absorption, total internal, and diffuse reflections. Capture of blue photons by the WLS fibers and subsequent re-emission of longer wavelength green photons is appropriately treated. The trapping and propagation of green photons inside the WLS fiber is treated using the laws of optics for meridional and skew rays. Propagation time of each photon is taken into account for the generation of the electrical signal at the photomultiplier. A comparison of the results from G3sim with the performance of a prototype scintillator detector showed an excellent agreement between the simulated and measured properties. The simulation results can be parametrized in terms of exponential functions providing a deeper insight into the functioning of these versatile detectors. G3sim can be used to aid the design and optimize the performance of scintillator detectors prior to actual fabrication that may result in a considerable saving of time, labor, and money spent.

Phase transition in an exactly solvable extinction model

We introduce a model of biological evolution in which species evolve in response to biotic interactions and fluctuating environmental stress. The species may either become extinct or mutate to acquire a new fitness value when the effective stress level is greater than their individual fitness. The model exhibits a phase transition to a completely extinct phase as the environmental stress or the mutation rate is varied. We discuss the generic conditions for which this transition is continuous. The model is exactly solvable and the critical behavior is characterized by an unusual dynamic exponent z=1/3. Apart from predicting large-scale evolution, the model can be applied to understand the trends in the available fossil data.

Driven k-mers: correlations in space and time

Steady-state properties of hard objects with exclusion interaction and a driven motion along a one-dimensional periodic lattice are investigated. The process is a generalization of the asymmetric simple exclusion process (ASEP) to particles of length k, and is called the k-ASEP. Here, we analyze both static and dynamic properties of the k-ASEP. Density correlations are found to display interesting features, such as pronounced oscillations in both space and time, as a consequence of the extended length of the particles. At long times, the density autocorrelation decays exponentially in time, except at a special k-dependent density when it decays as a power law. In the limit of large k at a finite density of occupied sites, the appropriately scaled system reduces to a nonequilibrium generalization of the Tonks gas describing the motion of hard rods along a continuous line. This allows us to obtain in a simple way the known two-particle distribution for the Tonks gas. For large but finite k, we also obtain the leading-order correction to the Tonks result.

Bimodal response in periodically driven diffusive systems

We study the response of one-dimensional diffusive systems, consisting of particles interacting via symmetric or asymmetric exclusion, to time-periodic driving from two reservoirs coupled to the ends. The dynamical response of the system can be characterized in terms of the structure factor. We find an interesting frequency-dependent response; the current-carrying majority excitons cyclically crosses over from a short wavelength mode to a long wavelength mode with an intermediate regime of coexistence. This effect being boundary driven decays inversely with system size. Analytic calculations show that this behavior is common to diffusive systems, both in the absence and presence of correlations.

A series report of autoimmune hypothyroidism associated with Hashimoto's encephalopathy: an under diagnosed clinical entity with good prognosis

Thyroid dysfunctions may be accompanied by numerous neurological and psychiatric disorders. The most well-known is cognitive impairment and depression in hypothyroid patients, as well as an increased risk of cerebrovascular accidents. A separate, although a rare entity, is Hashimoto's encephalopathy. Unlike encephalopathy associated with other conditions, management in Hashimoto's encephalopathy highly responds to steroid treatment and may be associated with normal thyroid profile at presentation. Hashimoto's encephalopathy, while rare, may have been under-recognised since its clinical presentation overlaps several more common disorders, such as depression, seizures or anxiety. We present two cases of hypothyroidism with peculiar presentation. The first case has rapidly progressive neurological dysfunction, normal thyroid function at presentation, normal MRI finding and responds to steroid treatment. The second case has a subacute progressive neurological deterioration with elevated thyroid-stimulating hormone titre at presentation. Both these cases are known hypothyroidism on regular thyroxin replacement therapy with elevated anti-thyroid peroxidase antibodies. We conclude that Hashimoto's encephalopathy can present with a wide spectrum of neurological illnesses in the setting of hypothyroidism. Thyroid status may vary from hypothyroid, normothyroid to even hyperthyroid. This condition usually has an abnormal electroencephalography (EEG) background and usually responds to high dose steroids.