How should emerging economies manage their foreign exchange reserves?

Asia has emerged as the balancing wheel of global finance. The countries of Asia now account for 70 per cent of global foreign exchange reserves, compared to only 30 percent in 1990 and 21 per cent in the early 1970s. This paper explores theoretical interpretations for the relatively high demand for international reserves by developing countries especially in the Far East. This paper provides calculations of the minimal necessary level of international reserves based on benchmarks proposed by Wijnholds and Kapteyn, as well as a discussion of costs of reserves’ holding. It therefore provides empirical proof that exchange reserve levels for many of the developing countries have far exceeded the desirable levels. Paper then discusses the steps that central banks in these developing countries can take for an effective reserve management.Foreign exchange ; emerging economies; reserves; reserve level; east asia

Calf Muscle Strain: Injury of the Gastronemius and Soleus

CLINICAL PRESENTATION & EXAM: Calf strains are usually the result of a sudden pushing off movement or over-stretching of the muscle and usually afflict athletes and others later in life. They occur more in men than women, and afflicted patients tend to report calf tightness days before the injury. During the patient history, the patient usually presents with a sharp pain at the back of the lower leg and has pain and weakness in active plantarflexion. Additionally, the patient should be observed for swelling, bruising, and overpronation. Resisted muscle tests and functional tests can be conducted, and if needed, special tests such as Thompson’s test for complete muscle rupture should be conducted in which the foot will plantar flex if the calf muscle is squeezed and the Achilles tendon is intact. ANATOMY & PATHOLOGY: The calf muscle consists of the big gastrocnemius muscle at the back of the lower leg and the soleus muscle that is smaller and is below and covered by the gastrocnemius. The gastrocnemius originates from the medial and lateral condyles of the femur bone, above the knee joint, and inserts into the heel through the Achilles tendon to the calcaneus. It is innervated by the tibial nerve and has the primary action of plantarflexion of the foot and secondary action of flexion at the knee. The soleus originates below the knee from the tibia and fibula and also inserts to the heel through the Achilles tendon. It shares the same innervation and plantarflexes the foot. Calf strains are commonly found in the medial head of the gastrocnemius, and the muscle as a whole is considered high risk because it crosses both the ankle and knee joints and has a high density of type II fast twitch muscle fibers, causing rapid and forceful contractions. The soleus is considered lower risk for injury and crosses only the ankle joint. Soleus muscle damage usually occurs lower in the leg and is not painful when bending the knee. DIAGNOSTIC TESTING & CONSIDERATIONS: Differential diagnosis of a gastrocnemius versus a soleus injury in a calf strain can be done through palpation and strength and flexibility testing. When palpating, tenderness in the musculotendinous junction indicates a gastrocnemius injury, whereas soleus strain pain is more lateral. Additional, gastrocnemius and soleus strains can be distinguished by plantarflexing the foot at varying degrees of knee flexion. In maximal flexion at the knee the soleus primarily plantarflexes, and in full extension the gastrocnemius is the primary plantarflexor. In addition to resisted, functional, and special tests on the calf muscle, imaging tests such as ultrasound and MRI may be needed as well to see the actual rupture or damage to the muscle. MRI can also show hematomas, which sometimes occur following serious injuries. TREATMENT & RETURN TO ACTIVITY: Calf muscle strains are graded from I-III, representing the degree of muscle fiber tear: \u3c10%, 10%-50%, and \u3e50%, respectively. The treatment depends on the grade; however in general the RICE technique should be utilized – rest, ice, compress, elevate – after which gentle stretching and massage can help ease the swelling and relax the muscle. In addition, a compression bandage or crutches should be used as needed. After some time, calf strain strengthening and rehabilitative exercises should be employed in the order of isometric, isotonic, and then dynamic contractions alongside passive stretching. NSAID’s should be restricted for first few days after which COX-2 inhibitors are an option. Acetaminophen or narcotic pain medication can also be used. If the strain is grade III, surgery may be required to reattach the damaged muscle and tendon

Developing Clinical Decision Support Systems for Sepsis Prediction Using Temporal and Non-Temporal Machine Learning Methods

In healthcare, diagnostic errors represent the biggest challenge to synthesize accurate treatments. In the United States, patient deaths due to misdiagnoses are estimated at 40,000 to 80,000 per year. It was also found that 30% of the annual healthcare spending was consumed on unnecessary services and other inefficiencies. The diagnostic errors could be reduced, and public health can be improved by applying machine learning and artificial intelligence in healthcare problems. This dissertation is an attempt to formulate clinical decision support systems and to develop new algorithms to reduce clinical errors.This dissertation aims at developing clinical decision support systems to diagnose sepsis in the early stages. The key feature of our work is that we captured the dynamics among body organs using Bayesian networks. The richness of the proposed model is measured not only by achieving high accuracy but also by utilizing fewer lab results.To further improve the accuracy of the clinical decision support system, we utilize longitudinal data to develop a mortality progression model. This part of the dissertation proposes a hidden Markov model (HMM) framework to model the mortality progression. In comparison to existing approaches, the proposed framework leverages the longitudinal data available in the electronic health records (EHR).In addition, this dissertation proposes an initialization procedure to train the parameters of HMM efficiently. The current HMM learning algorithms are sensitive to initialization. The proposed method computes an initial set of parameters by relaxing the time dependency in sequential time series data and incorporating the multinomial logistic regression.Finally, this dissertation compares the prognostic accuracy of two popularly used early sepsis diagnostic criteria: Systemic Inflammatory Response Syndrome (SIRS) and quick Sepsis-related Organ Failure Assessment (qSOFA). Using statistical and machine learning methods, we found that qSOFA is a better diagnostic criteria than SIRS. These findings will guide healthcare providers in selecting the best bedside diagnostic criteria

Case Finding For Pulmonary Tuberculosis Among People Who Inject Drugs In Dar Es Salaam, Tanzania

CASE FINDING FOR PULMONARY TUBERCULOSIS AMONG PEOPLE WHO INJECT DRUGS IN DAR ES SALAAM, TANZANIA. Akash Gupta. Jessie Mbwambo. Ibrahim Mteza. Sheela Shenoi. Barrott Lambdin. Cassian Nyandindi. Basra Ismail Doula, Said Mfaume, and Robert Douglas Bruce. Department of Internal Medicine, Yale University, School of Medicine, New Haven, CT. Active case finding is a World Health Organization (WHO)-endorsed strategy for improving case detection of tuberculosis. Despite WHO recommendations for active case finding among people who inject drugs (PWID), there are few published studies. The historical focus of case finding has been in populations that are HIV-positive, incarcerated, or at higher occupational risk. We sought to examine the yield of active case finding among PWID newly started on methadone in Tanzania. A questionnaire including tuberculosis symptoms and risk factors was administered to every consenting patient by a native Swahili-speaker. Additional chart review was performed for demographic information and HIV status. Two sputum samples were collected for every symptomatic patient, and samples were tested using smear microscopy as well as culture. A total of 156 of 222 (70%) methadone clients met with study administrators; 150 of whom consented to the study. Median age was 34 years old, and 139 (93%) were male. Thirty-four (23%) were HIV-positive, and an additional 104 (69%) had an unknown HIV status. Of the 150 patients surveyed, 16 (11%) had one or more tuberculosis symptoms and were referred for laboratory testing. Six new cases of tuberculosis were identified, 5 of which were sputum smear-negative, and 1 of which was multi-drug resistant. The prevalence of tuberculosis was 4% This study presents the first data on tuberculosis prevalence in a population of PWID in Tanzania. This prevalence is 23 times the general Tanzanian tuberculosis prevalence of 0.2%. PWID in Tanzania should continue to be screened for tuberculosis with smear, culture and drug susceptibility testing. Screening should expand to PWID in the community

ENGINEERING NANOMATERIALS FOR IMAGING AND THERAPY OF BACTERIA AND BIOFILM-ASSOCIATED INFECTIONS

Infections caused by multidrug-resistant (MDR) bacteria pose a serious global burden of mortality, causing thousands of deaths each year. The “superbug” risk is further exacerbated by chronic infections generated from antibiotic-resistant biofilms that are highly resistant to available treatments. Synthetic macromolecules such as polymers and nanoparticles have emerged as promising antimicrobials. Moreover, ability to modulate nanomaterial interaction with bacterial cellular systems plays a pivotal role in improving the efficacy of the strategy. In the initial studies on engineering nanoparticle surface chemistry, I investigated the role played by surface ligands in determining the antimicrobial activity of the nanoparticles. In further study, I determined that surface monolayer of hydrophobic ligands facilitated the nanoparticles to block bacterial efflux pumps, yielding reduction in antibiotic dosage to treat pathogenic bacteria including methicillin-resistant S. aureus (MRSA). Moreover, functionalization of nanoparticle surface with pH-responsive ligand was used to develop a general strategy to target and image bacterial biofilms for a broad-range of species. In a subsequent study, I have utilized a unique approach of integrating synthetic nanomaterials on the surface of natural super carrier-Red Blood Cells for selective delivery of nanoparticles to the site of bacterial infection for antimicrobial therapy. This strategy shows potential to combat bacterial infections without harming the ecology of human microbiome, as well as circumvent the issues associated with non-specific uptake of nanoparticles by the reticuloendothelial system. In another study, systematic investigation of antimicrobial activity of oxanorbornene-polymer derivatives generated polymer nanoparticles with unprecedented therapeutic selectivity towards MDR bacteria. Additionally, polymeric nanoparticles prevented onset of resistance development in bacteria for ~1300 generations and eradicate biofilms on infected mammalian cells, a feat unachieved by previous antimicrobial polymers. Amphiphilic polymer derivates increased the influx of antibiotics in Gram-negative bacteria and biofilms, resulting in synergistic antimicrobial therapy. Subsequently, we utilized engineered polymers to generate nanosponges through self-assembly of polymers around essential-oil based cores for topical treatment of wound biofilms. Overall, our results show strong potential as an infectious disease therapeutic while simultaneously provide a rational approach to design novel antimicrobials for sustainably combating bacterial infections

SPECTRAL DATABASE AND FRAMEWORK FOR COMPUTATIONALLY EFFICIENT CRYSTAL PLASTICITY SIMULATIONS

Most of the commercially used metals and alloys exhibit polycrystalline microstructures that are composed of numerous grains (individual crystals). In these metals and alloys, plastic deformation occurs mainly through the movement of dislocations. Crystal plasticity models have been developed and used over the past several decades to describe physically the behavior of metals. They not only provide better predictions of the anisotropic material response but can also capture the texture evolution in a polycrystalline sample. However, crystal plasticity models are extremely computationally expensive, limiting their adoption. In this work, this limitation is addressed by using a recently developed spectral database approach based on discrete Fourier transforms (DFTs). This approach has demonstrated impressive computational advantages over the conventional approaches. Despite their wide applicability, in some applications the DFT database approach has encountered significant hurdles such as for prediction of crystal plasticity based forming limit diagram (CP-FLD) and for carrying out simulations of crystal plasticity finite element method (CPFEM). Forming limit diagram (FLD) is the most commonly used indicator of localized necking in automotive industry. In this work, significant improvements were made to the prior approach and a new DFT database was developed to address these challenges. New database was integrated with M-K approach to develop spectral crystal plasticity forming limit diagram (SCP-FLD) numerical tool for very fast CP-FLD predictions. The new DFT database was also implemented with finite elements (FE) package ABAQUS through a user materials subroutine, UMAT to develop an improved spectral crystal plasticity finite element method (SCPFEM) framework, for computationally efficient CPFEM predictions of deformation processing. Proper utilization of these toolsets can lead to accelerated insertion of new and improved materials into practice.Ph.D

The Effects of Option Expiration on NSE volume and prices

This paper studies the effect of stock options expiration day on the underlying shares traded on the National Stock Exchange (NSE). Overall we tested for abnormal trading volume, abnormal price movement, individual stock reversal and stock pinning on expiration days. To the best of our knowledge, this is a first such study done on the Indian market.option expiration, indian market, nse, abnormal trading volume, abnormal price movement, individual stock reversal, stock pinning, stock price clustering

A protocol for automated a posteriori adaptive meshing with SimVascular: a test case

Objective Operational details regarding the use of the adaptive meshing (AM) algorithm available in the SimVascular package are scarce despite its application in several studies. Lacking these details, novice users of the AM algorithm may experience undesirable outcomes post-adaptation such as increases in mesh error metrics, unpredictable increases in mesh size, and losses in geometric fidelity. Here we present a test case using our proposed iterative protocol that will help prevent these undesirable outcomes and enhance the utility of the AM algorithm. We present three trials (conservative, moderate, and aggressive settings) applied to a scenario modelling a Fontan junction with a patient-specific geometry and physiologically realistic boundary conditions. Results In all three trials, an overall reduction in mesh error metrics is observed (range 47%–86%). The increase in the number of elements through each adaptation never exceeded the mesh size of the pre-adaptation mesh by one order of magnitude. In all three trials, the protocol resulted in consistent, repeatable improvements in mesh error metrics, no losses of geometric fidelity and steady increments in the number of elements in the mesh. Our proposed protocol prevented the aforementioned undesirable outcomes and can potentially save new users considerable effort and computing resources