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PubMed2002

Cross-reactivity among several recombinant calicivirus virus-like particles (VLPs) with monoclonal antibodies obtained from mice immunized orally with one type of VLP.

Human caliciviruses (HuCVs) are classified into the Norwalk-like viruses (NLV) and Sapporo-like viruses (SLV) as genera within the family CALICIVIRIDAE: The NLV genus is further classified into genogroups I and II, based on sequence similarities. To study the antigenic determinants on the HuCV capsid protein and develop new diagnostic tools for field samples, we established and characterized monoclonal antibodies (MAbs) against baculovirus-expressed recombinant HuCV virus-like particles (VLPs). Hybrid clones producing MAbs were obtained from cultures of PAI myeloma cells fused with spleen or mesenteric lymph node cells from mice immunized orally with either a single type of recombinant Norwalk virus (rNV), Kashiwa 47 virus (rKAV), Snow Mountain agent (rSMA), or Sapporo virus (rSV) VLP or with mixtures of two types of VLPs from different genogroups. Twenty MAbs, obtained as mouse ascites, were characterized and classified into six groups according to their enzyme-linked immunosorbent assay (ELISA) and Western blotting (WB) cross-reactivity patterns to VLPs. Five groups of MAbs reacted by both WB and ELISA and were classified as follows: common cross-reactive MAbs for four genogroup I and six genogroup II VLPs (group A), genogroup I-specific MAbs (group B), genogroup II-specific MAbs (group C), and strain-specific MAbs (groups D and E). One MAb group (group F) reacted only by ELISA. The group A MAbs, which showed broad cross-reactivity with VLPs of both NLV genogroups, were obtained from mice immunized orally with a single type of VLP (either rNV or rKAV). Two MAbs, which were obtained from mice immunized with rSV, reacted with rSV but not with any NLV VLP. These are the first MAbs to be reported for any SLV. These strain-, genogroup-, and genus-reactive MAbs will be useful tools for further study of the antigenic and structural topography of the HuCV virion and for diagnostic assays for HuCVs.

Animals↗
PubMed2006

Evidence of influenza a virus RNA in siberian lake ice.

Influenza A virus infects a large proportion of the human population annually, sometimes leading to the deaths of millions. The biotic cycles of infection are well characterized in the literature, including in studies of populations of humans, poultry, swine, and migratory waterfowl. However, there are few studies of abiotic reservoirs for this virus. Here, we report the preservation of influenza A virus genes in ice and water from high-latitude lakes that are visited by large numbers of migratory birds. The lakes are along the migratory flight paths of birds flying into Asia, North America, Europe, and Africa. The data suggest that influenza A virus, deposited as the birds begin their autumn migration, can be preserved in lake ice. As birds return in the spring, the ice melts, releasing the viruses. Therefore, temporal gene flow is facilitated between the viruses shed during the previous year and the viruses newly acquired by birds during winter months spent in the south. Above the Arctic Circle, the cycles of entrapment in the ice and release by melting can be variable in length, because some ice persists for several years, decades, or longer. This type of temporal gene flow might be a feature common to viruses that can survive entrapment in environmental ice and snow.

Base Sequence↗
PubMed1994

Sequence diversity of small, round-structured viruses in the Norwalk virus group.

We have determined the nucleotide sequences of a highly conserved region of the RNA-dependent RNA polymerase of the prototype Snow Mountain agent (SMA) and of four other small, round-structured viruses (antigenically Norwalk virus [NV]-like or SMA-like) following reverse transcription-PCR amplification of viral RNA obtained from human stools. The stool samples were either from volunteers administered SMA or from sporadic cases and outbreaks of gastroenteritis that occurred in Japan and the United Kingdom between 1984 and 1992. The GLPSG and YGDD RNA polymerase motifs were in the proper locations in the sequences of the five SRSVs, but each sequence was distinct from the 8FIIa prototype NV sequence and from each other. Analysis of the sequences and reactivities in a new NV antigen enzyme-linked immunosorbent assay showed that the five viruses could be divided into two groups (serogroups) with NV and SMA, respectively, being the prototypes. The sequences of the capsid region and a nonstructural region (2C) were determined from one strain from each group. One virus (SRSV-KY-89/89/J), isolated in Japan and antigenically similar to the prototype NV (isolated 21 years earlier in Ohio), showed a remarkable level of sequence similarity to NV. KY-89 and the 8FIIa NV showed 87.2% nucleotide similarity over 2,516 continuous nucleotides amounting to 96 to 98.9% amino acid similarity in three distinct domains in two open reading frames. Between the prototype SMA and NV, the polymerase region showed 63% nucleotide and 59% amino acid similarity, respectively. Two other antigenically SMA-like isolates (SRSV-925/92/UK and SRSV-OTH-25/89/J), from the United Kingdom and Japan, showed 80% nucleotide and 88 to 92% amino acid similarity in the polymerase region to the prototype SMA isolated 16 and 13 years earlier in the United States. The capsid region of the antigenically SMA-like OTH-25 virus showed 53% nucleotide and 65% amino acid similarity to the prototype NV capsid region. Domains of sequence diversity and conversation were identified within the capsid protein of these two distinct prototype serotypes of virus. These results indicate that NV-like and SMA-like agents are still circulating, and sequence comparisons will be useful to identify and classify distinct viruses in the NV group.

Base Sequence↗
PubMed2002

Binding of Norwalk virus-like particles to ABH histo-blood group antigens is blocked by antisera from infected human volunteers or experimentally vaccinated mice.

Attachment of Norwalk (NV), Snow Mountain (SMV), and Hawaii (HV) virus-like particles (VLPs) to specific ABH histo-blood group antigens was investigated by using human saliva and synthetic biotinylated carbohydrates. The three distinct Norwalk-like viruses (NLVs) have various capacities for binding ABH histo-blood group antigens, suggesting that different mechanisms for NLV attachment likely exist. Importantly, antisera from NV-infected human volunteers, as well as from mice inoculated with packaged Venezuelan equine encephalitis virus replicons expressing NV VLPs, blocked the ability of NV VLPs to bind synthetic H type 1, Le(b), and H type 3, suggesting a potential mechanism for antibody-mediated neutralization of NV.

ABO Blood-Group System↗
PubMed2004

Norovirus capture with histo-blood group antigens reveals novel virus-ligand interactions.

Noroviruses are genetically diverse, uncultivable, positive-sense RNA viruses and are the most common cause of epidemic acute gastroenteritis in humans in the United States. Recent studies of norovirus attachment in vitro by using recombinant virus-like particles (VLPs) suggest that various norovirus strains exhibit different patterns of attachment to ABH histo-blood group antigens, which are carbohydrate epitopes present in high concentrations on mucosal cell surfaces of the gut. However, attachment of live norovirus strains to histo-blood group antigens has not been investigated to date. Utilizing a newly designed magnetic bead-virus capture method, we characterized histo-blood group antigen attachment properties of various norovirus strains obtained from clinical stool specimens to compare the attachment properties of wild-type virus and VLPs and to further map norovirus attachment. Consistent with previous reports using VLPs, various strains of noroviruses exhibited different patterns of attachment to histo- blood group antigens. Norwalk virus bound specifically to H type 1, H type 3, and Le(b). Two genogroup II noroviruses, one representing the Toronto genotype and the other from a novel genotype, bound specifically to Le(b). A Desert Shield-like strain did not attach to H types 1, 2, or 3, H type 1 and 3 precursors, Le(a), or Le(b). Surprisingly, wild-type Snow Mountain virus (SMV) attached specifically to H type 3, which contradicted previous findings with SMV VLPs. On further investigation, we found that stool components promote this attachment, providing the first known observation that one or more components of human feces could promote and enhance norovirus attachment to histo-blood group antigens.

ABO Blood-Group System↗
PubMed2004

Effect of trail design and grooming on the incidence of injuries at alpine ski areas.

OBJECTIVES: To identify the conditions at certain sites on slopes known as black spots for injury. METHOD: In the Hafjell and Voss alpine ski areas in Norway, 1410 skiing injuries were recorded from December 1990 through the 1996 season. In Hafjell, 183 of these injuries were plotted on an area map during the two first seasons. Similarly, in Voss, 214 injuries were plotted on an area map for two seasons. During the last three seasons in Hafjell, 835 ski injuries were related to 6712 snow grooming hours and 6,829,084 lift journeys. RESULTS: The mean injury rate was 2.2 injuries per 1000 skier days, and the mean injury severity score (ISS) was 3.1. Accumulations of injuries at three sites (black spots) were recorded on the Hafjell area map. These injuries represented 40% of all injuries in the alpine area (p<0.05). Seven injury accumulation sites were recorded on the alpine area map of Voss, representing 22% of the total injuries (p>0.05). Grooming of the slopes was rated poor for the 49% of injuries that occurred at the sites of injury concentration and significantly different (27%) from injuries that occurred at random in Hafjell. The corresponding values in Voss were 50% and 25% respectively. Grooming hours appeared to be inversely proportional to the number of injuries: R = -0.99 (p<0.02). The mean ISS declined significantly in Hafjell over the observation period (p<0.001). CONCLUSION: Inappropriate trail design and slope grooming seem to result in an accumulation of injuries at certain sites. Modification in construction and maintenance of the courses may reduce the number of injuries and mean ISS.

Adolescent↗
PubMed2006

Injuries among elite snowboarders (FIS Snowboard World Cup).

BACKGROUND: Although snowboarding is already established as an Olympic sport, it is still a developing sport, with new disciplines, more demanding snow installations, and spectacular tricks. A recent study on subjects at Norwegian national elite level showed that injury risk is high and that injuries among competitive snowboarders differ from those seen in recreational snowboarders, with fewer wrist injuries and more knee and back injuries. OBJECTIVE: To describe the incidence and type of injuries among female and male snowboarders at international elite level. METHOD: At the last race of the Fédération Internationale de Ski Snowboard World Cup, acute injuries resulting in missed participation and overuse injuries influencing performance, were recorded during a retrospective interview (91% response rate). The registration period was from April 2002 (end of season) until March 2003. Exposure was recorded as the number of runs in all disciplines, and the incidence was calculated as number of injuries per 1000 runs. RESULTS: The 258 athletes interviewed reported 3193 competition days (n = 46 879 runs) in all disciplines. In total, 135 acute injuries were recorded; 62 (46%) during competition in the official disciplines. Of the 135 acute injuries, the most common injury locations were knee (n = 24; 18%), shoulder (n = 18; 13%), back (n = 17; 13%), and wrist (n = 11; 8%). The overall incidence during competition was 1.3 (95% confidence interval 1.0 to 1.7) injuries per 1000 runs; 2.3 (0.9 to 3.8) for big air (n = 10), 1.9 (1.1 to 2.8) for halfpipe (n = 21), 2.1 (1.2 to 3.0) for snowboard cross (n = 20), 0.6 (0.2 to 1.0) for parallel giant slalom (n = 8), and 0.3 (0.0 to 0.7) for parallel slalom (n = 3). The severity of injuries was graded based on time loss (27% lost >21 days) and score on the Abbreviated Injury Scale (AIS) (38% AIS 1, 61% AIS 2 and 1% AIS 3). There were 122 overuse injuries, 38 (31%) of these to the knee. CONCLUSION: The injury risk for big air, snowboard cross, and halfpipe disciplines is high, while that for the snowboard slalom disciplines is lower. The injury pattern is different from recreational athletes, with a greater share of knee injuries and fewer wrist injuries. Compared with national level, the injury risk appears to be lower at World Cup level.

Adult↗
PubMed2003

Effects of different sodium concentrations in replacement fluids during prolonged exercise in women.

OBJECTIVE: To investigate the effect of different sodium concentrations in replacement fluids on haematological variables and endurance performance during prolonged exercise. METHODS: Thirteen female endurance athletes completed three four hour runs on a 400 m track. Environmental conditions differed between the three trials: 5.3 degrees C and snow (trial 1), 19.0 degrees C and sunny weather (trial 2), 13.9 degrees C and precipitation (trial 3). They consumed 1 litre of fluid an hour during the trials with randomised intake of fluids: one trial (H) with high sodium concentration (680 mg/l), one trial (L) with low sodium concentration (410 mg/l), and one trial with only water (W). Before and after the trials, subjects were weighed and blood samples were taken for analysis of [Na(+)](plasma), packed cell volume, and mean corpuscular volume. RESULTS: The mean (SD) decrease in [Na(+)](plasma) over the whole trial was significantly (p<0.001) less in trial H (2.5 (2.5) mmol/l) than in trial W (6.2 (2.1) mmol/l). Mild hyponatraemia ([Na(+)](plasma) = 130-135 mmol/l) was observed in only six women (46%) in trial H compared with nine (69%) in trial L, and 12 (92%) in trial W. Two subjects (17%) in trial W developed severe hyponatraemia ([Na(+)](plasma)<130 mmol/l). No significant differences were found in performance or haematological variables with the three different fluids. There was no significant correlation between[Na(+)](plasma) after the run and performance. There was a significant correlation between changes in [Na(+)](plasma) and changes in body weight. CONCLUSIONS: Exercise induced hyponatraemia in women is likely to develop from fluid overload during prolonged exercise. This can be minimised by the use of replacement fluids of high sodium concentration. Sodium replacement of at least 680 mg/h is recommended for women in a state of fluid overload during endurance exercise of four hours. However, higher [Na(+)](plasma) after the run and smaller decreases in [Na(+)](plasma) during the trials were no indication of better performance over four hours.

Adult↗
PubMed2003

Ictal magnetoencephalographic discharges from elementary visual hallucinations of status epilepticus.

PURPOSE: To report the rare opportunity to study ictal magnetoencephalography (MEG) in a 26 year old man with simple partial status epilepticus that presented as elementary visual hallucinations (EVHs) in the right upper visual field. METHODS: The patient described his EVHs as "snowing on TV," "flickering lights," and "rotating coloured balls" that continued for several days. MEG and simultaneous EEG were recorded twice: during an episode of EVHs (ictal recordings) and after EVHs were controlled by medications (interictal recordings). RESULTS: During EVHs, MEG showed continuous periodic epileptiform discharges over the left posterior superior temporal region, while simultaneous EEG showed rhythmic theta waves and sporadic spikes over the left temporal region. The MEG discharge consisted of a three phase spike complex. Equivalent current dipoles (ECDs), modelled from spike complexes, localised in the left superior temporal area. After drug treatment controlled the EVHs, interictal MEG and EEG showed rare spikes over the same left temporal region. The average ictal ECD moment (mean (SD)) (128.7 (32.8 nAm)) was significantly weaker than the average interictal ECD moment (233.0 (63.9) nAm) (p<0.05). CONCLUSIONS: The continuous, periodic, and clustered discharges seen on ictal MEG were the sources of EVH. The weaker ictal ECD sources were frequently not detected by scalp EEG, while the stronger interictal sources, presumably originating from an extensive interictal zone, were sufficiently large to be seen as EEG spikes.

Adult↗
PubMed1994

Seroprevalence, risk factors and attitude to HIV-1 in a representative sample of lesbians in Turin.

OBJECTIVE: To estimate the HIV-1 seroprevalence, behavioural risks and attitude to HIV-1 infection among lesbians. SETTING: Institute of Infectious Diseases, University of Turin, Italy. SUBJECTS: From March 1992 to May 1993, 181 lesbians were tested for HIV-1 and included in the study. METHODS: Sociodemographic details, nonsexual risks for HIV-1, sexual behaviour, STD history and attitude to HIV-1 were obtained from an anonymous, standardised, self-administered, 30-item questionnaire. Snow-ball techniques were used to recruit the largest possible number of participants. RESULTS: 11 lesbians (6.1%) were found to be HIV-1 antibody positive. Of them, 10 were intravenous (i.v.) drug users. STD episodes were higher among lesbians with HIV-1 than without (p = 0.04), increasing in both groups over time. Syphilis, genital herpes and viral hepatitis were highly associated with HIV-1 (p = 0.000). In univariate analysis, i.v. drug use, bisexual behaviour, history of STDs, sex during menses and vaginal/anal manipulation were significantly linked to HIV-1 (p = 0.000). In multivariate analysis only history of i.v. drug use (p = 0.04) and bisexual behaviour (p = 0.06) remained independently associated with HIV-1. Seventy-one participants (39.3%) had already undergone AIDS testing. Only 3.5% admitted to be at risk for HIV-1 and 11% changed their sex habits after first hearing of AIDS. No lesbian had ever practised safe-sex. Television was the most important source of information on HIV-1 (84%). CONCLUSION: I.v. drug use was the most likely means of HIV-1 infecting the lesbians of Turin. The high rate of STDs and the low perceived risk to HIV-1 require programmes of STD prevention and AIDS information to be targeted at the lesbian community.

Acquired Immunodeficiency Syndrome↗
PubMed1979

The effects of a pesticide program on microbial populations from apple leaf litter.

The leaf litter microbial community was quantitatively and qualitatively changed when a standard pesticide schedule that comprised an insecticide, a bactericide, and a fungicide was applied to McIntosh apple trees in the summer. Effects were observed for two winters by four indirect assays and three direct methods. Populations were altered qualitatively both years, but the most striking difference was the quantitative impact from year to year. Bacteria, filamentous fungi, and yeasts from treated leaves were reduced 10- to 10 000-fold between November 1976 and April 1977 and did not recover until snow cover had melted in March. Reductions in 1977-1978 were negligible. The marked seasonal difference is attributed to meteorological influences. Fluorescent pseudomonads were among the bacteria depressed by chemicals. Of the 49 genera of fungi and yeasts isolated, Coniothyrium sp., Penicillium spp., Arthrobotrys spp., and Nodulisporium sp. were appreciably reduced, whereas Typhula spp., Pleurophomella sp., Sporobolomyces spp., and Rhodotorula spp. were substantially enhanced by the spray program.

Azinphosmethyl↗
PubMed2000

Production of cellulases and xylanases by low-temperature basidiomycetes.

Three of four isolates, representing phylogenetically distinct groupings of low-temperature basidiomycetes (LTB), were capable of utilizing wheat straw, and to a lesser extent conifer wood at 15 degrees C. A cottony snow mould LTB (LRS 013) and a fruit rot LTB (LRS 241) grown on straw significantly degraded filter paper, carboxymethylcellulose (CMC), p-nitrophenyl beta-glucopyranoside (i.e., beta-glucosidases), and xylan. Enzymes produced by Coprinus psychromorbidus (LRS 067) were limited to xylanases from straw and wood and beta-glucosidases from wood. A sclerotia-forming LTB (LRS 131) exhibited poor growth on both substrates, and did not produce detectable quantities of extracellular enzymes. None of the LTB isolates tested degraded avicel. The temperature optima of CMCases and xylanases in the filtrates from the straw medium ranged from 25 degrees C to 55 degrees C, and with the exception of LRS 067, significant activity was observed at 5 degrees C. Two cellulases (25 and 31 kDa) and two xylanases (24 and 34 kDa) were observed on zymograms for LRS 013 and 241. Reduction of enzymes with 2-mercaptoethanol adversely affected their activity on zymograms, and an additional cellulase band was observed for non-reduced samples. This study indicates that LTB produce an array of cellulolytic and xylanolytic enzymes, and that some of these enzymes possess low-temperature optima which may facilitate degradation of plant fibre under low-temperature conditions.

Basidiomycota↗
PubMed1979

Modes of thermal protection in polar bear cubs--at birth and on emergence from the den.

At birth in late December the polar bear is small (700 g), uninsulated, and helpless. It probably has a modest capacity for metabolic heat production and depends on the female and a snow den in which it is born for thermal protection. The microclimate of an artificial polar bear den was investigated at Point Barrow, AK, and the temperature therein found to stay around 0 degrees C provided a heat source (200 W) equivalent to an adult polar bear was introduced. When the bears desert the den in early April the cub has grown to about 10 kg and has a well-developed fur insulation, but almost no subcutaneous fat. The cub has a high resting metabolic rate (4.6 W.kg-1), which is supported by the fat polar bear milk. Its lower critical temperature is about -30 degrees C, and an ambient temperature of -45 degrees C results in only a 33% increase in metabolism. The cub can tolerate a wind chill of 2.3 kW.m2 without apparent stress of drop in rectal temperature. If the cub is immersed in ice water rectal temperature drops 11 degrees C in 30 min. It is concluded that the cub can tolerate extremely low temperatures in air due to fur insulation and high metabolic heat production, but is unable to cope with the chill of ice water for any prolonged period of time.

Adipose Tissue↗
PubMed1978

Optimal rate of work for mountaineers.

The physiological responses of seven young male highlanders were recorded at high altitude while they were carrying loads (0, 25, 35, 45, and 55 kg) on snow at different speeds, supporting the loads on their backs by circular straps around the forehead. The rates of work calculated from the gross weight (body weight plus actual load in kg) multiplied by the speed of walking, m.min-1, ranged from 4,460 to 8,440 kg.m.min-1. The relationship between the rate of work and energy expenditure was rectilinear within the present range of values. The oxygen consumption (51.6 and 59.7 ml.min-1.kg-1 BW) for 55-kg load (at 4.09 and 4.64 km.h-1) possibly reached maximal aerobic capacity. At higher energy output at high altitude the subjects were exhausted after a short period of work. The proportion of increase of oxygen consumption per kg gross weight carried or per kg.m was almost constant up to a 55-kg experimental load. It is suggested that for day-to-day operations work should not be undertaken at more than 30-40% of maximal work capacity; a rate of work around 4,000 kg.m.min-1 (25-30 kg actual load at 3.0 to 3.5 km.h-1) may be considered as optimal for highlanders and porters at high altitude.

Adaptation, Physiological↗
PubMed1984

Ten years of "civilization": fitness of Canadian Inuit.

Data on the cardiorespiratory fitness of the Canadian Inuit has been obtained before and after 10 yr exposure to "white civilization." The population tested comprises 201 males (aged 9-76 yr) and 143 females (aged 10-69 yr), about 70% of the eligible population of Igloolik (69 degrees 40'N). During direct maximum tests to exhaustion, a higher maximum heart rate was attained in 1980-81 (194.4 beats X min-1) than in 1970-71 (184.5 beats X min-1); this probably reflects a closer approach to a centrally limited maximum as the Inuit have become familiar with white investigators. The Astrand nomogram currently underestimates the directly measured maximum O2 intake (VO2max) by some 3% in subjects making a good maximum effort. Comparing the 1980-81 data with results for 1970-71, there has been a 15% decrease of predicted VO2max, accompanied by a 2- to 4-kg increase of body mass, accumulation of subcutaneous fat, and a decrease of leg extension strength, these changes affecting all subjects except boys aged 9-15 yr. It is suggested that the loss of personal fitness is related to adoption of a more sedentary lifestyle, particularly the use of tracked vehicles in place of walking through deep snow.

Adolescent↗
PubMed1999

Skeletal muscle energy metabolism during prolonged, fatiguing exercise.

A depletion of phosphocreatine (PCr), fall in the total adenine nucleotide pool (TAN = ATP + ADP + AMP), and increase in TAN degradation products inosine 5'-monophosphate (IMP) and hypoxanthine are observed at fatigue during prolonged exercise at 70% maximal O(2) uptake in untrained subjects [J. Baldwin, R. J. Snow, M. F. Carey, and M. A. Febbraio. Am. J. Physiol. 277 (Regulatory Integrative Comp. Physiol. 46): R295-R300, 1999]. The present study aimed to examine whether these metabolic changes are also prevalent when exercise is performed below the blood lactate threshold (LT). Six healthy, untrained humans exercised on a cycle ergometer to voluntary exhaustion at an intensity equivalent to 93 +/- 3% of LT ( approximately 65% peak O(2) uptake). Muscle biopsy samples were obtained at rest, at 10 min of exercise, approximately 40 min before fatigue (F-40 =143 +/- 13 min), and at fatigue (F = 186 +/- 31 min). Glycogen concentration progressively declined (P < 0.01) to very low levels at fatigue (28 +/- 6 mmol glucosyl U/kg dry wt). Despite this, PCr content was not different when F-40 was compared with F and was only reduced by 40% when F was compared with rest (52. 8 +/- 3.7 vs. 87.8 +/- 2.0 mmol/kg dry wt; P < 0.01). In addition, TAN concentration was not reduced, IMP did not increase significantly throughout exercise, and hypoxanthine was not detected in any muscle samples. A significant correlation (r = 0.95; P < 0. 05) was observed between exercise time and glycogen use, indicating that glycogen availability is a limiting factor during prolonged exercise below LT. However, because TAN was not reduced, PCr was not depleted, and no correlation was observed between glycogen content and IMP when glycogen stores were compromised, fatigue may be related to processes other than those involved in muscle high-energy phosphagen metabolism.

Adenine Nucleotides↗
PubMed1998

[Obstetrics--a gear in the machinery of history].

It was not Julius Caesar who was born by Caesarean section, as generally assumed, but Scipio Cornelius Africanus, who subdued Spain 100 years before Caesar's time. In chambers with walls of porphyrite, the Byzantine empresses used to give birth to the heirs to the throne. In England, the infertility of Queen Anne, who suffered from porphyria, led to the succession of the Protestant House of Hannover following the Catholic Stuarts. Christina of Sweden, called 'queen of baroque, rebel and scholar', was born in the 'caul'. At the age of 39 years, Johanna of Pfirt, married to Albrecht the Lame, secured the continuation of the Habsburg dynasty by giving birth to Rudolf the Founder. Maria Theresia, who had 16 children, was called 'mother-in-law of Europe'. She was delivered of her first child at the age of 19. The death of her sister Maria-Anna in childbed was one of the reasons why Gerard van Swieten was called to Vienna. Elisabeth of Württemberg, first wife of Franz I of Austria, died, not as a consequence of. but after a forceps operation carried out by Johann Lukas Boër. In England, Princess Charlotte, daughter of George IV, and her baby son died at the delivery; Sir Richard Croft, who had not used the forceps, committed suicide after this tragic incident. Being the next in succession, Victoria ascended the throne. The term 'narcose au chloroforme' (first used by James Young Simpson) was changed to 'narcose à la reine' after this method had been used at the birth of Victoria's eighth child by John Snow. It was Queen Victoria, who passed on haemophilia in European dynasties. When Marie Louise of Habsburg had her first child, Napoleon's son, the later Duke of Reichstadt, Antoine Dubois had to perform a turning of the transverse presentation and use the forceps on the head following after. The birth of Napoleon himself was a case of precipitate labour. Johann Klein, the successor of Boër, applied the forceps when Archduchess Sophie was delivered of her first child, the later Emperor Franz Joseph I of Austria, the first of the four 'salt princes'. The later Emperor Wilhelm II of Prussia was delivered by Eduard Arnold Martin the Elder, the obstetrician of Princess Victoria, the eldest daughter of Queen Victoria; the breech presentation became even more complicated by the raised arms of the child. Both latter monarchs had been 'asphyctic' after their birth. Johann Wolfgang von Goethe was also among those who were apparently dead after their birth.

Cesarean Section↗
PubMed1997

A real-time method for generating random-dot motion displays of specified coherence.

A method that allows the creation of moving random-dot patterns with any desired level of motion coherence is presented. In the present context, a random-dot pattern with 100% coherence is a sliding sheet of dots (all dots move at the same speed and in the same direction). A random-dot pattern with 0% coherence is visual dynamic noise (similar to detuned TV snow). Coherences between 100% and 0% have a specific percentage of the dots moving coherently together, while the remaining 'twinkle' in a random fashion. The use of look-up table animation allows the dot patterns to move smoothly and rapidly even on computers that lack computational speed. Additionally, the coherence of the motion in a particular region of the screen is determined by the spatial arrangement of pixel indices in that local region. Therefore, this technique allows different regions of the screen to have different levels of coherence which makes the creation of motion-defined shapes straightforward. The basics of look-up table animation are discussed and a general algorithm for creating motion with any level of coherence is presented.

Algorithms↗