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IVGTT was performed in 16 extra-obese patients in order to evaluate the validity of the test in the functional biochemical study of massive obesity. Various glucose doses were used in order to identify the amount providing a constant glycaemic trend and therefore a reliable KG.
OBJECTIVE: The authors evaluated how quantum computing threatens the cryptographic primitives used in Bitcoin and other blockchain systems. These findings were translated into a standards-aligned post-quantum migration profile for healthcare ledgers, including consent, identity, provenance, audit, and encrypted off-chain data exchange. METHODOLOGY: Narrative analysis, theoretical security analysis, and healthcare-oriented deployment mapping of classical public-key and hash primitives used in blockchain protocols were paired with an implementation-oriented migration profile based on finalized National Institute of Standards and Technology (NIST) post-quantum standards. We summarize the mathematical assumptions underlying RSA, Elliptic Curve Cryptography/Elliptic Curve Digital Signature Algorithm (ECC/ECDSA), and Secure Hash Algorithm (SHA-2/SHA-3-family) hash functions; analyze their susceptibility to Shor's and Grover's quantum algorithms; compare Federal Information Processing Standards (FIPS) 203 Module-Lattice-Based Key-Encapsulation Mechanism Standard (ML-KEM), FIPS 204 Module-Lattice-Based Digital Signature Standard (ML-DSA), and FIPS 205 Stateless Hash-Based Digital Signature Standard (SLH-DSA); and map their distinct roles to healthcare-ledger authorization, auditability, identity, and encrypted off-chain exchange. The term Advanced Hybrid Module-LWE & Code-Based (AHMC) is used only as shorthand for a standards-aligned hybrid post-quantum cryptography (PQC) migration profile and does not denote a proprietary product, a novel algorithm, or a new cryptographic primitive. Proposed adoption of hybrid, quantum-resistant cryptographic primitives for cryptocurrency wallets, transaction signatures, and ledger security during an interim migration period (hybrid classical + PQC, followed by PQC-only). Qualitative and implementation-oriented assessment of (1) break feasibility of RSA/ECC under Shor's algorithm, (2) effective security reduction for hash functions under Grover's algorithm, (3) security assumptions and composition requirements of a standards-aligned hybrid migration profile, (4) transaction-size and verification-cost impact, and (5) healthcare-specific implications for long-retention consent, identity, provenance, and audit records. RESULTS: Shor's algorithm reduces integer factorization and discrete logarithms to polynomial time, directly compromising Rivest-Shamir-Adleman (RSA) and ECC/ECDSA once fault-tolerant, large-scale quantum computers exist. Grover's algorithm yields a quadratic speedup for brute-force search, effectively halving the security margin of symmetric keys and hash functions at fixed output sizes. The AHMC-L1/L3/L5 profiles use ML-KEM-512/768/1024 for key establishment and ML-DSA-44/65/87 for transaction authentication, with SLH-DSA as a hash-based fallback. During a hybrid ECDSA+PQC migration, verification requires one classical and one PQC verification per authorization; transaction-size overhead is dominated by PQC signatures, approximately 2.4 KB for ML-DSA-44, 3.3 KB for ML-DSA-65, and 4.6 KB for ML-DSA-87 before script and encoding overhead. For healthcare ledgers, these findings support selective use of post-quantum signatures for:high-value state transitions,one-time public-key registration where possible, andcontinued off-chain storage of protected health information.Deployment suitability remains contingent on workflow-specific latency, storage, availability, key lifecycle, and side-channel testing. CONCLUSIONS: Quantum risk to blockchain signatures has direct implications for healthcare systems that depend on long-lived consent, identity, provenance, and audit records. A staged, standards-aligned migration profile can preserve authorization and ledger verifiability while keeping protected health information off-chain. The AHMC label refers only to this migration profile, not to a new cryptographic primitive; healthcare adoption requires open implementations, empirical benchmarking, crypto-agile key governance, and side-channel-resistant engineering.
While the thermochemical stability of gas-phase HgF4 against F2 elimination was predicted by accurate quantum chemical calculations more than a decade ago, experimental verification of "truly transition-metal" mercury(IV) chemistry is still lacking. This work uses detailed density functional calculations to explore alternative species that might provide access to condensed-phase Hg(IV) chemistry. The structures and thermochemical stabilities of complexes Hg(IV)X4 and Hg(IV)F2X2 (X- = AlF4-, Al2F7-, AsF6-, SbF6-, As2F11-, Sb2F11-, OSeF5-, OTeF5-) have been assessed and are compared with each other, with smaller gas-phase HgX4 complexes, and with known related noble gas compounds. Most species eliminate F2 exothermically, with energies ranging from only about -60 kJ mol(-1) to appreciable -180 kJ mol(-1). The lower stability of these species compared to gas-phase HgF4 is due to relatively high coordination numbers of six in the resulting Hg(II) complexes that stabilize the elimination products. Complexes with AsF6 ligands appear more promising than their SbF6 analogues, due to differential aggregation effects in the Hg(II) and Hg(IV) states. HgF2X2 complexes with X- = OSeF5- or OTeF5- exhibit endothermic fluorine elimination and relatively weak interactions in the Hg(II) products. However, elimination of the peroxidic (OEF5)2 coupling products of these ligands provides an alternative exothermic elimination pathway with energies between -120 and -130 kJ mol(-1). While all of the complexes investigated here thus have one exothermic decomposition channel, there is indirect evidence that the reactions should exhibit nonnegligible activation barriers. A number of possible synthetic pathways towards the most interesting condensed-phase Hg(IV) target complexes are proposed.
Determination of the equation that relates an ordered dependent variable to ordered independent variables is sought. One solution, non-parametric discriminant analysis (NPD), involves obtaining the best monotonic step function by means of a computer search procedure. Although one can use alternative selection criteria in obtaining the equation, the illustrative examples use absolute distance. This paper compares the prediction procedures obtained from NPD with those from linear discriminant analysis, linear regression (with and without transformed variables), and logistic regression. We show that NPD is analogous to regression tree analysis with incorporation of ordered variables and monotonicity. We use various prediction functions to predict the example data, the data using the leave-one-out technique, and a verification set. Consistently, non-parametric discriminant analysis performs as good as or better than the tested alternatives.
In order to successfully use a model for parameter identification, it must be carefully analyzed. Current analysis methods, however, are ad hoc and provide only partial information. We extended these methods through the application of stacked dimensions, a scientific visualization method. The end result of our extensions are multi-dimensional parametric model-images. These images depict a model as a function of all its parameters in a single graphic. We applied parametric model-images to model verification (behavioral analysis), sensitivity analysis, and identifiability analysis. We applied our methodology to the evaluation of pulmonary vascular capillary-transport models. Results have shown that the visualization-based method provides a more complete view of a model's behavior and its other characteristics. Furthermore, our method has also proven to be more computationally efficient than the traditional approaches.
BACKGROUND: The visualization of any morphological volume (i.e. CT, MRI) together with an additional second morphological volume (i.e. CT, MRI) or functional data set, which may come from SPECT or PET, is a new method for treatment planning, verification and follow-up of interstitial irradiation. METHOD: The authors present their experience on interstitial irradiation of brain tumours with stereotactically implanted I-125 seeds supported by image fusion. The image fusion was performed by the BrainLab-Target 1.13 software on Alfa 430 (Digital) workstation before, during, and after interstitial irradiation of brain tumours with Iodine125 seeds. RESULTS AND INTERPRETATION: On the basis of 20 brachytherapeutic image fusion of stereotactic CT (slices with fiducials) with additional stereotactic CT, MRI, PET and SPECT images provides more accurate and precise target volume, more exact localization of catheters and isotope seeds (verification fusion), differentiation between the localization and amount of the necrotic and proliferating parts of the tumours and shows the volume changes in consequence of interstitial irradiation. The image fusion should help to improve the accuracy and minimize the perifocal morbidity of interstitial irradiation.
The trafficking of the androgen receptor (AR) in transfected cells was studied using a green fluorescent protein (GFP)-AR chimera. The reporter molecule GFP enabled the localization of AR in living cells with a good spatial and temporal resolution. After the construction of GFP-AR and verification of the size of the fusion protein produced, we demonstrated that GFP-AR conserves the functional properties of the AR: GFP-AR had the same androgen-binding affinity as AR, and GFP-AR efficiently transactivated an androgen-responsive gene in response to synthetic androgen at 30 degrees C. The fusion protein was first detected throughout the cytoplasm without hormone, fluorescence becoming nuclear rapidly after androgen incubation. This hormone dependence of AR trafficking was confirmed by the use of the mutant GFP-AR-del4, which lacked the androgen-binding function. The mutant was localized in the cytoplasm in the absence of hormone, but the distribution was not modified by androgen incubation. An ACAS 570 scanning laser cytometer was used to quantify fluorescence in a single living cell, first without and then with hormone. Different hormones and antihormones were tested to determine the dynamics of GFP-AR translocation into the nucleus. All the drugs used were able to induce nuclear translocation, and steady state level was rapidly attained within 1 h. The ratio of receptors in cytoplasmic and nuclear compartments was related to both affinity and concentration of ligand. The data from this follow-up study demonstrated for the first time the intracellular dynamics of the hormone-dependent trafficking of AR in a single living cell.
In a previous paper, one of the authors suggested an analytical method for calculation of the response function of an alpha spectrometer for the case of large solid angles. This paper describes the experimental verification of the method. Spectra of a well-known natural uranium sample were measured with a 450 mm2 Si detector and compared to the theoretical predictions. The measurements were carried out with two different geometrical configurations. In both cases a good agreement was observed between experimental and theoretical results.
Nucleotide composition and distribution along a DNA sequence is known to play a vital role in the determination of gene functions. Protein coding regions, regulatory sequences, and other functional regions are determined generally by homology studies with comparable genes from other species or specific experimental verification. With the rapid and explosive increase in sequence information, new computational techniques for rapid determination of such information and comparative studies of different genes are becoming necessary which ideally should encompass not only DNA sequences but other macromolecular sequences as well.
The object of this study is to elucidate whether the quantitative determination of serum pancreatic type iso-amylase can be used as a diagnostic test for exocrine pancreatic insufficiency. We describe the normal appearance of serum amylase zymograms produced with an agarose electrophoresis technique and the reference values from studies of 142 normal subjects for salivary and pancreatic type amylases. The patient group comprises 95 cases assumed to be representative of a patient population in which verification or exclusion of a diagnosis of chronic pancreatitis is of importance. In this group exocrine pancreatic function has been assessed by means of the Lundh meal test. We find that a low serum pancreatic type amylase value indicates the presence of a reduced exocrine pancreatic function (p = 0.96), and that a normal or elevated serum pancreatic type amylase value excludes the presence of a severe exocrine pancreatic insufficiency (p = 0.91). We also describe the occurrence of an abnormal amylase fraction which may be of diagnostic significance in pancreatic disease.
Knowing that 20-30% of intra-uterine growth retardation are unexplained, the authors assume a psychological component that may influence fetal growth. A first psychologic approach consisted in having interviews with about fifty women who had just given birth to small-size babies. The analysis of the contents of these interviews, performed in the free association mode, allowed screening six psychopathologic themes : denial of pregnancy, painful emotional or physical experiences, operative functioning mode, unessential role of the husband, lack of an imaginary child, and previous affective deprivation. The verification of the hypothesis arising from the psychological approach will be based on a complementary epidemiological approach.
Neuropsychological changes distinguishing mild Alzheimer's disease (AD) from frontotemporal dementia (FTD) have been described, but empirical verification of differential cognitive characteristics is lacking. Archival neuropsychological data on 15 FTD patients, 16 AD patients, and 16 controls were compared. Controls outperformed both patient groups on measures of verbal and nonverbal memory, executive ability, and constructional skill, with AD patients showing more widespread memory decline. No differences were found between the 3 groups in confrontation naming, recognition memory, or basic attention. Patient groups differed only in nonverbal memory, with FTD patients performing significantly better than AD patients. However, patient groups also differed in pattern of performance across executive and memory domains. Specifically, AD patients exhibited significantly greater impairment on memory than executive tasks, whereas the opposite pattern characterized the FTD group. These findings suggest that examination of relative rankings of scores across cognitive domains, in addition to interpretation of individual neuropsychological scores, may be useful in differential diagnosis of FTD versus AD.
Recently we have shown that the major antigenic sites of bovine serum albumin exhibit functional equivalence progessively increasing with the time at which antibodies are obtained after the first immunization. Analysis of our recent immunochemical findings and the known covalent structure of bovine serum albumin have enabled us to predict the locations of five antigenic sites of bovine serum albumin. The predicted locations were synthesized, and immunochemical studies with late-course antisera showed them to constitute antigenic sites of native bovine serum albumin.
Twenty seven frontalis sling procedures were performed with use of autogenous fascia-lata. The choice of this procedure was performed sometimes at the first stage for severe ptosis with poor levator function: isolated congenital ptosis, blepharophimosis syndrome, Marcus Gunn Jaw-Winking ptosis, ptosis with severe myopathy, some traumatic ptosis. This procedure was also performed in a second stage after failure of the useful procedures (levator resection) and after verification that the levator was not exploitable. Sometimes the choice of the procedure is done during the exploration of the eyelid and the levator because there is not always "parallelism" between the levator function and his anatomy. So operative technique must always be performed by a complete anterior palpebral approach, the surgeon can passed the suspensory material from the tarsus to the roof of the orbit, just anterior to the levator aponeurosis, and then out above the eyebrow. The pulley this created by the periosteum of the superior orbital margin prevents vertical traction lines. The skin crease is created with sutures which pick up the tarsus and the lid retractors. If, during the explorations the levator is "exploitable", a super maximum levator resection will be performed at the first stage, the frontalis suspension will be maintained in case of failure of the levator resection.
A receiver operating characteristic (ROC) curve is commonly used to measure the accuracy of a medical test. It is a plot of the true positive fraction (sensitivity) against the false positive fraction (1-specificity) for increasingly stringent positivity criterion. Bias can occur in estimation of an ROC curve if only some of the tested patients are selected for disease verification and if analysis is restricted only to the verified cases. This bias is known as verification bias. In this paper, we address the problem of correcting for verification bias in estimation of an ROC curve when the verification process and efficacy of the diagnostic test depend on covariates. Our method applies the EM algorithm to ordinal regression models to derive ML estimates for ROC curves as a function of covariates, adjusted for covariates affecting the likelihood of being verified. Asymptotic variance estimates are obtained using the observed information matrix of the observed data. These estimates are derived under the missing-at-random assumption, which means that selection for disease verification depends only on the observed data, i.e., the test result and the observed covariates. We also address the issues of model selection and model checking. Finally, we illustrate the proposed method on data from a two-phase study of dementia disorders, where selection for verification depends on the screening test result and age.
BACKGROUND CONTEXT: Epidural steroid injection (ESI) is one of the most common nonsurgical interventions prescribed for back and leg pain symptoms. Although the use of ESI is widespread, proof of efficacy among the broad population of low back pain patients is lacking and use is predicated to a great extent on the cost and morbidity of the perceived "next step" in many patient's care-surgery. PURPOSE: To review the relative indications and clinical features that predict success with ESI therapy, and to provide a physiological rationale to guide clinical decision-making. STUDY DESIGN/SETTING: Review of literature and clinical experience. RESULTS: Clinical studies have alternately supported and refuted the efficacy of ESI in the treatment of patients with back and leg pain. Steroid medications do benefit some patients with radicular pain, but the benefit is often limited in duration, making efficacy difficult to prove over time. Steroids appear to speed the rate of recovery and return to function, however, allowing patients to reduce medication levels and increase activity while awaiting the natural improvement expected in most spinal disorders. Fluoroscopic verification of needle placement, with contrast injection, greatly improves steroid delivery while reducing risks. Although it is assumed that the benefit of steroids is related to their effect on inflammation, that remains unproven, and it is possible that benefit is gained through an unrecognized action. CONCLUSIONS: Randomized, controlled trials are needed to conclusively identify those patients most likely to benefit from ESI, and when and for how long. Until then, epidural steroids provide a reasonable alternative to surgical intervention in selected patients with back and/or leg pain, whose symptoms are functionally limiting. When appropriate goals are established and proper patients are selected, sufficient short-term benefit has been documented to warrant continued use of this tool.
The technique of functional magnetic resonance imaging (fMRI) has the capacity to acquire data with spatial and temporal resolution that far exceeds other currently available methods of non-invasive investigation of brain function. This coupled with its ability for serial studies makes it an attractive prospect for investigating the effects of pharmacological agents in the brain. Recent advances in fMRI have been made in the areas of reward and dependence, brain trauma and injury, psychotropic drugs and pain using small animals. Although the use of fMRI in pharmacological studies is becoming popular, there are various associated complications, such as the possible interference of drugs with the mechanisms that give rise to the pharmacological fMRI signal, and local or global cardiovascular changes that might produce functional responses unrelated to neural activity. Consideration of these concerns, coupled with careful attention to experimental detail and verification procedures, promises to make pharmacological fMRI use a valuable tool for understanding the actions of drugs in the brain.
PURPOSE: A prototype Miniature Multi-Leaf Collimator (MMLC) designed specifically for radiosurgery and small field radiotherapy has been fabricated and evaluated at the University of Texas M. D. Anderson Cancer Center (UTMDACC). This work demonstrates the advantages of a computer-controlled MMLC vs. conventional circular collimation for the treatment of an irregularly shaped target volume in the brain. METHODS AND MATERIALS: Two patient treatments were selected for this comparison from 38 intracranial tumors treated with radiosurgery at UTMDACC from 8/6/91 to 5/10/94. Target contours and critical structures defined for one of the patients was used to create a simulated target volume and critical structures in a spherical head phantom. Computer simulations were performed using traditional single isocenter treatment with a circular collimator for a set of six arcs. The same arc paths were used to compute the dose distribution for the MMLC and conformed beam geometries were defined using a three-dimensional (3D) treatment planning system with beam's eye view capabilities. Then, the calculated dose distribution for a single isocenter, conformal treatment was delivered to the spherical head phantom under static conditions by shaping the MMLC to conform the target volume shape projected as a function of couch rotation and gantry angle. Planar dose distributions through the target volume were measured using therapy verification film located in the phantom. The measurements were used to verify that the 3D treatment planning system was capable of simulating the MMLC technique. For the second patient with a peanut-shaped tumor, the 3D treatment planning calculations were used to compare dose distributions for the MMLC and for traditional single and multiple isocenter treatments using circular collimators. The resulting integral dose-volume histograms (DVHs) for the target volume, normal brain, and critical structures for the three treatment techniques were compared. RESULTS: (a) Analysis of the film dosimetry data exemplified the degree of conformation of the high-dose region to the target shape that is possible with a computer-controlled MMLC. (b) Comparison of measured and calculated dose distributions indicates that the 3D treatment planning system can simulate the MMLC treatment. (c) Comparison of DVHs from the single isocenter MMLC and circular collimator treatments shows similar coverage of the target volume with increased dose to the brain for circular collimation (4). Comparison of DVHs from the single isocenter MMLC with the multiple isocenter circular collimator treatment approach shows a more inhomogeneous dose distribution through the target volume and increased dose to the brain for the latter. CONCLUSION: Dosimetry data for single isocenter treatments using computer-controlled field shaping with a MMLC demonstrate the ability to conform the dose distribution to an irregularly shaped target volume. DVHs validated that the single isocenter MMLC treatment is preferable to both single and multiple isocenter, circular collimator treatment because it provides a more uniform dose distribution to an irregularly shaped target volume and reduces the dose to surrounding brain tissue for the example cases.