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PubMed2006

Scattering of light by a periodic structure in the presence of randomness. V. Detection of successive peaks in a periodic structure.

We address the problem of detecting periodic structures hidden behind roughness. We have shown that if r(0) is the coherence length of the scattered radiation, due to the random part of the surface, and Lambda is the wavelength of the periodic part of the surface, then with a matched filtering method that we introduce, and by using simple computations with the intensity data, it is possible to detect the hidden first-order peak even when (r(0)/Lambda) approximately 0.11. Here we advance the method to bring out very weak second-order peaks, which we demonstrate for what we believe is the first time. The unmistakable presence of both the first- and second-order peaks, which have identical shapes as the zeroth-order peak, is strong evidence of the hidden periodicity and serves as a novel method for the detection of weak periodicities hidden behind strong randomness.

Journal Article↗
PubMed2005

Individual mice can be distinguished by the period of their islet calcium oscillations: is there an intrinsic islet period that is imprinted in vivo?

Pulsatile insulin secretion in vivo is believed to be derived, in part, from the intrinsic glucose-dependent intracellular calcium concentration ([Ca2+]i) pulsatility of individual islets. In isolation, islets display fast, slow, or mixtures of fast and slow [Ca2+]i oscillations. We show that the period of islet [Ca2+]i oscillations is unique to each mouse, with the islets from an individual mouse demonstrating similar rhythms to one another. Based on their rhythmic period, mice were broadly classified as being either fast (0.65 +/- 0.1 min; n = 6 mice) or slow (4.7 +/- 0.2 min; n = 15 mice). To ensure this phenomenon was not an artifact of islet-to-islet communication, we confirmed that islets cultured in isolation (period: 2.9 +/- 0.1 min) were not statistically different from islets cultured together from the same mouse (3.1 +/- 0.1 min, P > 0.52, n = 5 mice). We also compared pulsatile insulin patterns measured in vivo with islet [Ca2+]i patterns measured in vitro from six mice. Mice with faster insulin pulse periods corresponded to faster islet [Ca2+]i patterns, whereas slower insulin patterns corresponded to slower [Ca2+]i patterns, suggesting that the insulin rhythm of each mouse is preserved to some degree by its islets in vitro. We propose that individual mice have characteristic oscillatory [Ca2+]i patterns, which are imprinted in vivo through an unknown mechanism.

Animals↗
PubMed1992

The analysis of new short-period circadian rhythm mutants suggests features of D. melanogaster period gene function.

A number of new period gene (per) mutants were generated by in vitro mutagenesis and germ line transformation. Missense mutations were made at amino acid 589, which is altered in the 19 h short-period (per(s)) mutant, and insertion mutations were generated with peptides commonly used for epitope tagging. Most of these new per mutants had short behavioral rhythms. Flies with heteroallelic combinations of these new mutant per genes were found to have "hybrid" periods, i.e., they had values that were usually in between those of the individual alleles. These findings suggest that short-period per mutants are not unusual gain-of-function mutants but rather more traditional loss-of-function mutants that are unable to influence the circadian pacemaker in a proper manner. The data also suggest that the per protein may engage in important intermolecular interactions.

Animals↗
PubMed1998

Medicare program; schedules of per-visit and per-beneficiary limitations on home health agency costs for cost reporting periods beginning on or after October 1, 1998--HCFA. Notice with comment period.

This notice with comment period sets forth revised schedules of limitations on home health agency costs that may be paid under the Medicare program for cost reporting periods beginning on or after October 1, 1998. These limitations replace the limitations that were set forth in our January 2, 1998 notice with comment period (63 FR 89) and our March 31, 1998 final rule with comment period (63 FR 15718).

Budgets↗
PubMed2005

Medicare program; electronic submission of cost reports: revision to effective date of cost reporting period. Interim final rule with comment period.

This interim final rule with comment period revises the existing effective date by which all organ procurement organizations (OPOs), rural health clinics (RHCs), Federally qualified health centers (FQHCs), and community mental health centers (CMHCs) are required to submit their Medicare cost reports in a standardized electronic format from cost reporting periods ending on or after December 31, 2004 to cost reporting periods ending on or after March 31, 2005. This interim final rule with comment does not affect the current cost reporting requirement for hospices and end-stage renal disease (ESRD) facilities. Hospices and ESRD facilities are required to continue to submit cost reports under the Medicare regulations in a standardized electronic format for cost reporting periods ending on or after December 31, 2004.

Centers for Medicare and Medicaid Services, U.S.↗
PubMed2006

[Poisoning accidents with household chemicals among children in the period 1993-2002 compared with the period 1980-1992].

INTRODUCTION: The aim of this study was, in order to help prevent poisoning accidents in the future, to see if the pattern of poisoning accidents involving household chemicals among children changed in the Odense area in the period 1993-2002 compared to the period 1980-1992. MATERIALS AND METHODS: A review is presented of the registration of all poisoning accidents among children aged 0-6 years treated at Odense University Hospital, Denmark, during the period 1993-2003. The results are compared to results from the period 1980-1992. RESULTS: There were 1,426 poisoning accidents, of which 396 were accidents involving household chemicals. 369 of the accidents involving household chemicals were in the age group 0-3 years and 27 in the age group 4-6 years. We did not find any decrease in the number of accidents when we compared it with the number occurring in the previous 10 years. Most of the accidents took place in the home. DISCUSSION: It is necessary to continue with campaigns to prevent accidents involving household chemicals among children. It is parents' responsibility to ensure that chemicals are kept out of the reach of children.

Accidents, Home↗
PubMed1991

Biting periodicity index of Culex quinquefasciatus & its relationship with microfilaria periodicity in Pondicherry.

The biting periodicity index of the bancroftian filariasis vector, C. quinquefasciatus, was calculated on the basis of a large longitudinal data base and compared with the periodicity index of microfilariae of Wuchereria bancrofti. The biting periodicity index of the vector population was 29.78 and found to be close to the periodicity index of the microfilariae. The peak biting activity of the vector and peak appearance of microfilariae in the peripheral blood occurred at about 01.00 h, which accounts for the optimum infection of the vector population. The early night biting density of the vector population showed a highly significant (P less than 0.0005) linear relationship with all night biting density.

Animals↗
PubMedDate not supplied

Mortality in eclampsia in the Lagos University Teaching Hospital (LUTH); comparison of the recent 10-year period (1977-1986) with the previous 10 year period (1967-1976).

Over a 10-year period, between 1st January 1977 and 31st December 1986, a total of 572 eclamptic patients were treated in the Lagos University Teaching Hospital (LUTH). Three hundred and eighty-four of these patients (66.4%) were pre-delivery eclamptics, while 188 (33.6%) were post-partum eclamptics. The great majority of these cases (448) (98.3%) were unbooked patients. The overall maternal deaths from eclampsia or its complications during the period were 62 (108 per 1000) while the known perinatal deaths associated with the condition was 100 (240 per 1000). The mean Caesarean Section (C/S) rate in the pre-delivery eclamptics was 30.22 +/- SD 19.62%, while the mean C/S rate in all eclamptic patients treated in LUTH during this period was 22.20 +/- SD 15.04%. Comparison of the data from the recent decade to that of the previous decade (1966-1976), shows that the number of eclamptic patients treated in the LUTH, over the recent decade (1977-1986) more than doubled the number of eclamptics treated in the previous decade (1967-1976) (572 as compared with 273 for the previous decade). The overall maternal mortality rate remained unchanged (106 to 108 per 1000), while the perinatal mortality rate increased from 117 per 1000 to 240 per 1000 in the recent decade respectively. The C/S rate in the pre-delivery eclamptics increased during the period from 21.3% in the previous decade to 30.2% in the recent decade. The unbooked eclamptic patients remain the dominant group in the two studies.

Adult↗
PubMed1997

[Spanish scientific production in biomedicine and health sciences during the period 1990-1993 (Science Citation Index and Social Science Citation Index) and comparison to period 1986-1989].

BACKGROUND: In 1993 a first study on the scientific production of Spain in 1986-1989 on Biomedicine and Health Sciences, through the Science Citation Index (SCI) was published. The analysis attained the level of centres, with special emphasis in those related to the Health Care System. This paper analyses the period 1990-1993, offers a wider coverage including the Social Science Citation Index (SSCI) database, and compares both time periods. MATERIAL AND METHODS: Documents indexed by SCI and SSCI, CD-ROM version, with at least one Spanish address, published in biomedical and medical journals during the years 1990, 1991, 1992 and 1993, have been studied. Quantitative and qualitative bibliometric indicators for the analysis by subject matter, geographic distribution, institutional sector and centre of origin have been used. Global data were also analysed according to economic and human resources. RESULTS: A total of 21,434 documents were studied, of which 67.9% were journal articles. The highest contributors were Universities (48.8% of the documents) and Hospitals (45.3%). The autonomous communities of Madrid (31.9%) and Catalonia (26.9%) concentrate more than half the production-developed principally by hospitals-followed by Andalucía (11.7%) and C. Valenciana (7.8%). The most active disciplines were biochemistry/molecular biology (13%), neurosciences/neurology (8.4%), pharmacology/pharmacy (8.4%) and medicine, general/internal (7.9%). Comparing the results with period 1986-1989, some of the differences observed could be explained by the fact of MEDICINA CLINICA being included in SCI since 1992. An increase in the number of citable items (72.9%), number of journals used (from 1,086 to 1,346) and international cooperation rate (13.5% to 18.3%) was detected. The institutional sectors with the highest growth rate were Hospitals (92.9%) and Consejo Superior de investigaciones Cientificas (CSIC) (119.3%). Scientific production and visibility of publications (measured as impact factor of journals used) grew in most disciplines, being the quantitative increase greater in cancer/oncology, gastroenterology/hepatology, genetics/heredity and cardiovascular system. No substantial changes as to geographic distribution of documents or most active centres were observed. CONCLUSIONS: Spanish scientific activity grew steadily every year and its visibility improved, being the Health sector one of the main actors. When comparing both four-year period. Spain moved up from the seventh to the sixth position in the ranking of EU countries according to its scientific output in biomedicine and health sciences.

Databases, Bibliographic↗
PubMed2001

Periodic and quasi-periodic behavior in resource-dependent age structured population models.

To describe the dynamics of a resource-dependent age structured population, a general non-linear Leslie type model is derived. The dependence on the resources is introduced through the death rates of the reproductive age classes. The conditions assumed in the derivation of the model are regularity and plausible limiting behaviors of the functions in the model. It is shown that the model dynamics restricted to its omega-limit sets is a diffeomorphism of a compact set, and the period-1 fixed points of the model are structurally stable. The loss of stability of the non-zero steady state occurs by a discrete Hopf bifurcation. Under general conditions, and after the loss of stability of the structurally stable steady states, the time evolution of population numbers is periodic or quasi-periodic. Numerical analysis with prototype functions has been performed, and the conditions leading to chaotic behavior in time are discussed.

Age Distribution↗
PubMed2004

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS): definition, semiology, prognosis, pathogenesis, treatment, and place relative to other periodic joint diseases.

Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is an autosomal dominant inherited condition of periodic fever and pain. Most patients are of northern European descent. The attacks manifest as fever and pain in the joints, abdomen, muscles, skin, or eyes, with variations across patients. An acute-phase response occurs during the attacks. Patients with TRAPS are at risk for AA amyloidosis, the most common targets being the kidneys and liver. Soluble TNFRSF1A is usually low between the attacks and may be normal during the attacks, when TNF levels are high. TNFRSF1A is found in abnormally high numbers on leukocyte cell membranes. TRAPS is the first condition for which naturally occurring mutations in a TNF receptor were found; the mutations affect the soluble TNFRSF1A gene in the 12p13 region. In some patients, the pathogenesis involves defective TNFRSF1A shedding from cell membranes in response to a given stimulus. Thus, TRAPS is a model for a novel pathogenic concept characterized by failure to shed a cytokine receptor. This review compares TRAPS to other inherited periodic febrile conditions, namely, familial Mediterranean fever, Muckle-Wells syndrome, cold urticaria, and hyper-IgD syndrome. The place of TRAPS relative to other intermittent systemic joint diseases is discussed. Colchicine neither relieves nor prevents the attacks, whereas oral glucocorticoid therapy is effective when used in dosages greater than 20 mg/day. The pathogenic hypothesis involving defective TNFRSF1A shedding suggests that medications targeting TNF may be effective in TRAPS.

Adolescent↗
PubMed2001

Phosphorylation of period is influenced by cycling physical associations of double-time, period, and timeless in the Drosophila clock.

The clock gene double-time (dbt) encodes an ortholog of casein kinase Iepsilon that promotes phosphorylation and turnover of the PERIOD protein. Whereas the period (per), timeless (tim), and dClock (dClk) genes of Drosophila each contribute cycling mRNA and protein to a circadian clock, dbt RNA and DBT protein are constitutively expressed. Robust circadian changes in DBT subcellular localization are nevertheless observed in clock-containing cells of the fly head. These localization rhythms accompany formation of protein complexes that include PER, TIM, and DBT, and reflect periodic redistribution between the nucleus and the cytoplasm. Nuclear phosphorylation of PER is strongly enhanced when TIM is removed from PER/TIM/DBT complexes. The varying associations of PER, DBT and TIM appear to determine the onset and duration of nuclear PER function within the Drosophila clock.

Animals↗
PubMed2005

Hereditary periodic fever syndrome sans fever or distinct periodicity presenting with psychosis.

The genetic basis for several hereditary periodic fever syndromes has been identified and consequently, the phenotypic spectrum of these disorders has broadened. We describe a young woman with tumor necrosis factor receptor-associated periodic syndrome (TRAPS), proven by mutational analysis, who presented with psychosis but without fever, symptom periodicity, or similar family medical history. This patient represents the first case of TRAPS-associated psychosis. This case illustrates the importance of mutation analysis for this group of disorders in individuals presenting with unexplained inflammatory symptoms and recurrent psychoses.

Adolescent↗
PubMed2006

Exercise test in the inter-attack period of thyrotoxic periodic paralysis: a useful diagnostic tool.

Exercise test was reported to be useful for some patients with periodic paralysis. We report here the results of exercise test in three cases of thyrotoxic periodic paralysis, for whom the exercise test was all positive. Exercise test could be one of the diagnostic tools in the "inter-attack" state of the probable cases with thyrotoxic periodic paralysis. However, the case number of this study is small and larger-scale studies may be warranted in the future.

Action Potentials↗
PubMed1991

Periodic acid-Schiff-positive organisms in primary cutaneous Bacillus cereus infection. Case report and an investigation of the periodic acid-Schiff staining properties of bacteria.

Primary cutaneous Bacillus cereus infection frequently presents as a single necrotic bulla on the extremity of an immunocompromised patient. In lesional biopsy specimens and smears, the large gram-positive rods of B cereus may be mistaken for Clostridium species. This is a potentially serious error, as Bacillus species are resistant to penicillin and other beta-lactam antibiotics. We studied a case in which large periodic acid-Schiff-staining organisms were seen in the biopsy specimen from a necrotic bulla on the finger of a neutropenic patient with diffuse large cell lymphoma. The tissue biopsy specimen subsequently yielded a pure culture of B cereus. Staining with periodic acid-Schiff was then performed on a series of bacterial species in human tissue and from smears of culture colonies. The following bacterial species were found to be consistently periodic acid-Schiff positive after diastase digestion: B cereus, Corynebacterium diphtheriae, Propionibacterium acnes, Klebsiella pneumoniae, and Micrococcus luteus.

Aged↗
PubMedDate not supplied

[Periodicity of the changes in DNA and RNA levels in Penicillium chrysogenum conidia at the stage preceding the S-period].

It is ascertained, that conidia enter S-period after 11 hours of incubation on Capek-Dock medium and after 7 hours of incubation on Reistrick medium. Five peaks of DNA and RNA synthesises preceding the S-period were revealed. Moreover, DNA decay to a certain degree depending on the peak number is characteristic for every DNA synthesis peak. By the moment the cell enters into S-period the amount of DNA remains at the initial level. It is noted, that the RNA synthesis curve corresponds to the character of the DNA synthesis curve. A hypothesis is offered to explain the data obtained, which pressuposes the non-specific duplication of the greater part of the genome and its selective degradation.

DNA, Fungal↗
PubMed1979

Spatial periodicities of periodic complex cells in the visual cortex cluster at one-half octave intervals.

Within individual penetrations in the visual cortex, spatial periodicities of periodic complex cells differ by either one-half or one octave. When data are pooled from neurons subserving the central visual area in many cats, the results indicate that spatial periodicities cluster at one-half octave intervals over a 2 1/2-octave range (0.95 to 5.4 cyc/deg). Thus a relatively small number of such channels spaced at regular intervals along a logarithmic scale within each orientation column may suffice for this stage of spatial processing.

Animals↗
PubMed1980

[Comparative monitoring of pre-ejection-period and transcutaneously measured pO2 in neonatal period (author's transl)].

UNLABELLED: Pre-ejection period (PEP) and transcutaneous measured pO2 (tc pO2) were monitored simultaneously with the beat-to-beat ECG in 55 cases of unselected neonates. In addition body weight, acid-base-status and body temperature were registered 11 neonates were monitored immediately post partum, the others at various times until 9 days after delivery. RESULTS: The mean value of PEP after delivery is 63,3 msec. There is a negative correlation between neonatal heart rate and Pre-ejection-period. Increases of body temperature leads to a decrease of the PEP and vice versa. There are no direct significant alterations in PEP in connection with changes in neonatal tc pO2. Only when tc pO2-values beyond 20 mmHg were registered in distressed neonates PEP shortened significantly. PEP shortened also in periods of neonatal crying PEP is not correlated to birth weight or the actual neonatal weight when measurement of PEP and tc pO2 was performed.

Body Temperature↗