TRANSMISSION DYNAMICS OF ENTERIC BACTERIA IN DAY-CARE CENTERS, HOUSTON, TEXAS

An investigation was undertaken to evaluate the role of fomites in the transmission of diarrhea in day-care centers (DCC) and to elucidate the paths by which enteric organisms spread within this setting.^ During a nine-month period (December 1980-August 1981) extensive culturing of inanimate objects, as well as children and staff was done routinely each month and again repeated during diarrhea outbreaks. Air was sampled from the classrooms and toilets using a Single-Stage Sieve Sampler (Ross Industries, Midland, VA.). Stool samples were collected from both ill and well children and staff in the affected rooms only during outbreaks. Environmental samples were processed for Shigella, salmonella and fecal coliforms while stools were screened for miscellaneous enteropathogens.^ A total of 11 outbreaks occurred in the 5 DCC during the study period. Enteric pathogens were recovered in 7 (64%) of the outbreaks. Multiple pathogens were identified in 3 outbreaks. The most frequently identified pathogen in stools was Giardia lamblia which was recovered in 5 (45%) of the outbreaks. Ten of the 11 (91%) outbreaks occurred in children less than 12 months of age.^ Environmental microbiology studies together with epidemiologic information revealed that enteric organisms were transmitted from person-to-person. On routine sampling, fecal coliforms were most frequently isolated from tap handles and diaper change areas. Contamination with fetal coliforms was wide-spread during diarrhea outbreaks. Fecal coliforms were recovered with significantly greater frequency from hands, toys and other classroom objects during outbreaks than during non-outbreak period. Salmonella typhimurium was recovered from a table top during an outbreak of Salmonellosis. There was no association between the level of enteric microbial contamination in the toilet areas and the occurrence of outbreaks. No evidence was found to indicate that enteric organisms were spread by the airborne route via aerosols.^ Toys, other classroom objects and contaminated hands probably play a major role in the transmission of enteropathogens during day-care center outbreaks. The presence of many enteric agents in the environment undoubtedly explains the polymicrobial etiology of the day-care center associated diarrhea outbreaks. ^

Tuberculosis in Texas correctional facilities between 2005--2009

It has been well documented that inmates incarcerated in prisons and correctional facilities exhibit higher incidence and prevalence of mycobacterium tuberculosis (TB) disease than the general population. This has public health implications because correctional systems may serve as reservoirs for TB disease that can lead to TB outbreaks in the facilities or can be spread to the general public once inmates are released. Although Texas has one of the largest correctional systems in both the US and the world, little is known about TB prevalence and incidence among Texas inmates. The purpose of this study was to elucidate the relationship between TB incidence and incarceration in Texas correctional facilities and investigate differences in various demographic factors. ^ The study used the national TB database from the US Centers for Disease Control and Prevention (CDC) to calculate and compare the overall incidences of TB disease among correctional facility inmates and similar non-inmates in Texas during 2005–2009. Data were also stratified by age, gender, race/ethnicity, birth status, and HIV status and compared between inmates and non-inmates using chi-squared analysis and relative risks with 95% confidence intervals to assess any significant differences. ^ Results suggest that the overall TB incidence among Texas correctional facility inmates per year (88.6 per 100,000) was significantly higher than that of Texas non-inmates (6.3 per 100,000); a 14 fold difference. Relative risk analyses by gender, race/ethnicity, and those with HIV infection found that the TB incidences for all these demographics were significantly and consistently higher in inmates compared to non-inmates. In particular, Hispanic inmates were more likely to develop TB than their non-inmate counterparts by a relative risk of 23.9 (95% CI 19.4–29.4). Likewise, both male and female inmates were more likely to develop TB than non-inmates (RR = 10.2, 95% CI 8.5–12.2; RR = 20.8, 95% CI 12.2–25.3, respectively), although female inmates unconventionally exhibited a higher TB incidence and relative risk than males inmates, which has not been shown. Among those with HIV infections, correctional facility inmates were 2.6 times were likely to develop TB disease than non-inmates (95% CI 1.5–4.4). ^ Inmates in Texas correctional facilities have a higher incidence of TB than non-inmates. Part of this higher risk may be because a large proportion of inmates come from populations already at high risks for TB, such as foreign born immigrants, those infected with HIV, and low SES groups such as many racial/ethnic minorities. Thus, these results may be used as a basis for more controlled and detailed research in the area, and to further characterize incarceration as a risk factor for TB incidence. They may also bring much needed attention about this health disparity to public health officials, legislators, and health administrators to expand and improve TB control in Texas correctional facilities, particularly among inmates released to the community, and reduce the risk of TB transmission to the general population.^

Dengue transmission risk maps of the continental United States

Dengue fever is a strictly human and non-human primate disease characterized by a high fever, thrombocytopenia, retro-orbital pain, and severe joint and muscle pain. Over 40% of the world population is at risk. Recent re-emergence of dengue outbreaks in Texas and Florida following the re-introduction of competent Aedes mosquito vectors in the United States have raised growing concerns about the potential for increased occurrences of dengue fever outbreaks throughout the southern United States. Current deficiencies in vector control, active surveillance and awareness among medical practitioners may contribute to a delay in recognizing and controlling a dengue virus outbreak. Previous studies have shown links between low-income census tracts, high population density, and dengue fever within the United States. Areas of low-income and high population density that correlate with the distribution of Aedes mosquitoes result in higher potential for outbreaks. In this retrospective ecologic study, nine maps were generated to model U.S. census tracts’ potential to sustain dengue virus transmission if the virus was introduced into the area. Variables in the model included presence of a competent vector in the county and census tract percent poverty and population density. Thirty states, 1,188 counties, and 34,705 census tracts were included in the analysis. Among counties with Aedes mosquito infestation, the census tracts were ranked high, medium, and low risk potential for sustained transmission of the virus. High risk census tracts were identified as areas having the vector, ≥20% poverty, and ≥500 persons per square mile. Census tracts with either ≥20% poverty or ≥500 persons per square mile and have the vector present are considered moderate risk. Census tracts that have the vector present but have <20% poverty and <500 persons per square mile are considered low risk. Furthermore, counties were characterized as moderate risk if 50% or more of the census tracts in that county were rated high or moderate risk, and high risk if 25% or greater were rated high risk. Extreme risk counties, which were primarily concentrated in Texas and Mississippi, were considered having 50% or greater of the census tracts ranked as high risk. Mapping of geographic areas with potential to sustain dengue virus transmission will support surveillance efforts and assist medical personnel in recognizing potential cases. ^

Comparisons of z values between fine-grained titanomagnetites within interstitial glass and large-grained titanomaghemtes in older ocean-floor basalts

Transmission electron microscopy observations and rock magnetic measurements reveal that alteration of fine- and large-grained iron-titanium oxides can occur at different rates. Fine-grained titanomagnetite occurs as a crystallization product within interstitial glass that originated as an immiscible liquid within a fully differentiated melt; in several samples with ages to 32 Ma it displays very little or no oxidation (z = ca. 0). In contrast, samples with ages of 10 Ma or older are observed to also contain highly oxidized (z >/= 0.66) large-grained titanomaghemite. These large grains, having originated by direct crystallization from melt, are associated with pore space. Such pore space can serve as a conduit for fluids that promote alteration, whereas fine grains may have been "armored" against alteration by the glass matrix in which they are embedded. Apparently, alteration of oceanic crust is a heterogeneous process on a microscopic scale. The existence of pristine, fine-grained titanomagnetite in the interstitial glass of older ocean-floor basalts that have undergone significant alteration implies that such glassy material is capable of carrying original thermal remanent magnetization and may be suitable for paleointensity determinations.

Hydrogen and oxygen stable isotope analyses of precipitation sampled at Erlangen (southern Germany) between 2010 and 2013

Shallow groundwater aquifers are often influenced by anthropogenic contaminants or increased nutrient levels. In contrast, deeper aquifers hold potentially pristine paleo-waters that are not influenced by modern recharge. They thus represent important water resources, but their recharge history is often unknown. In this study groundwater from two aquifers in southern Germany were analyzed for their hydrogen and oxygen stable isotope compositions. One sampling campaign targeted the upper aquifer that is actively recharged by modern precipitation, whereas the second campaign sampled the confined, deep Benkersandstein aquifer. The groundwater samples from both aquifers were compared to the local meteoric water line to investigate sources and conditions of groundwater recharge. In addition, the deep groundwater was dated by tritium and radiocarbon analyses. Stable and radiogenic isotope data indicate that the deep-aquifer groundwater was not part of the hydrological water cycle in the recent human history. The results show that the groundwater is older than ~20,000 years and most likely originates from isotopically depleted melt waters of the Pleistocene ice age. Today, the use of this aquifer is strictly regulated to preserve the pristine water. Clear identification of such non-renewable paleo-waters by means of isotope geochemistry will help local water authorities to enact and justify measures for conservation of these valuable resources for future generations in the context of a sustainable water management.

Phytoplankton production, photosynthetic (P vs E) parameters, and particulate organic carbon and nitrogen within distinct water masses of eastern Australian coastal and shelf waters between 29 °S and 36 °S during spring 2010

The present dataset is part of an interdisciplinary project carried out on board the RV Southern Surveyor off New South Wales (Australia) from the 15th to the 31st October 2010. The main objective of the research voyage was to evaluate how the East Australian Current (EAC) affects the optical, chemical, physical, and biological water properties of the continental shelf and slope off the NSW coast.

Physical oceanography and current meter measurements on the Gulf of Lion continental margin between June 1993 and July 1996

Nine hydrographic cruises were performed on the Gulf of Lion continental margin between June 1993 and July 1996. These observations are analysed to quantify the fluxes of particulate matter and organic carbon transported along the slope by the Northern Current and to characterise their seasonal variability. Concentration of particulate matter and organic carbon are derived from light-transmission data and water sample analyses. The circulation is estimated from the geostrophic current field. The uncertainty on the transport estimate, related to the error on the prediction of particle concentrations from light-transmission data and the error on velocities, is assessed. The particulate matter inflow entering the Gulf of Lion off Marseille is comparable to the Rhône River input and varies seasonally with a maximum transport between autumn and spring. These modifications result from variations of the water flux rather than variations of the particulate matter concentration. Residual transports of particulate matter and organic carbon across the entire Gulf of Lion are calculated for two cruises enclosing the domain that were performed in February 1995 and July 1996. The particulate matter budgets indicate a larger export from the shelf to deep ocean in February 1995 (110 ± 20 kg/s) than in July 1996 (25 ± 18 kg/s). Likewise, the mean particulate organic carbon export is 12.8 ± 0.5 kg/s in February 1995 and 0.8 ± 0.2 kg/s in July 1996. This winter increase is due to larger allochthonous and autochthonous inputs and also to enhanced shelf-slope exchange processes, in particular the cascading of cold water from the shelf. The export of particulate matter by the horizontal currents is moreover two orders of magnitude larger than the vertical particulate fluxes measured at the same time with sediment traps on the continental slope.

Inflation targeting in Korea, Indonesia, Thailand, and the Philippines : the impact on business cycle synchronization between each country and the world

This paper empirically analyzes whether and to what extent the adoption of inflation targeting (IT) in Korea, Indonesia, Thailand and the Philippines has affected their business cycle synchronization with the rest of the world. By employing the dynamic conditional correlation (DCC) model developed by Engle (2002), we find that IT in Asia has little effect on international business cycle synchronization and the effect is positive in some of the countries, if any. These findings basically seem to be consistent with the evidence from relevant literature.

Evaluation of the influence of visual parameters on wave transmission velocity in sawn chestnut timber

Non-destructive, visual evaluation and mechanical testing techniques were used to assess the structural properties of 374 samples of chestnut (Castanea sativa). The principal components method was applied to establish and interpret correlations between variables obtained of modulus of elasticity, bending strength and density. The static modulus of elasticity presented higher correlation values than those obtained using non-destructive methods. Bending strength presented low correlations with the non-destructive parameters, but there was some relation to the different knot ratios defined. The relationship was stronger with the most widely used ratio, CKDR. No significant correlations were observed between any of the variables and density.

Spatio-temporal dynamics of viruses are differentially affected by parasitoids depending on the mode of transmission by their insect vectors.

Relationships between agents in multitrophic systems are complex and very specific. Insect-transmitted plant viruses are completely dependent on the behaviour and distribution patterns of their vectors. The presence of natural enemies may directly affect aphid behaviour and spread of plant viruses, as the escape response of aphids might cause a potential risk for virus dispersal. The spatio-temporal dynamics of Cucumber mosaic virus (CMV) and Cucurbit aphid-borne yellows virus (CABYV), transmitted by Aphis gossypii in a non-persistent and persistent manner, respectively, were evaluated at short and long term in the presence and absence of the aphid parasitoid, Aphidius colemani. SADIE methodology was used to study the distribution patterns of both the virus and its vector, and their degree of association. Results suggested that parasitoids promoted aphid dispersion at short term, which enhanced CMV spread, though consequences of parasitism suggest potential benefits for disease control at long term. Furthermore, A. colemani significantly limited the spread and incidence of the persistent virus CABYV at long term. The impact of aphid parasitoids on the dispersal of plant viruses with different transmission modes is discussed.

Simulation of the transmission performance for equalized holographic ROADM designs

A complete simulation of the transmission performance for Equalized Holographic ROADM (Reconfigurable Optical Add-Drop Multiplexer) designs is presented in this paper. These devices can address several wavelengths from the input to different output fibres, according to the holograms stored in a SLM (Spatial Light Modulator), where all the outputs are equalized in power. All combinations of the input wavelengths are possible at the different output fibres. To simulate the transmission performance of the EH-ROADM, a software program, from Optiwave, has been used. The correspondence between physical blocks of the device (grating, SLM, lens...) and those simulated in the program (filters, losses, splitters...) has been defined in order to obtain a close agreement between the theoretical transmission performance and the simulated one. To complete the review about Equalized Holographic ROADMs some guidelines about its design have been done.

Hybrid Contribution of JPEG200 Video Files for Professional Production Centers Reliability and Non-Reliability Transmission File Based in Image Quality Needed

ATM, SDH or satellite have been used in the last century as the contribution network of Broadcasters. However the attractive price of IP networks is changing the infrastructure of these networks in the last decade. Nowadays, IP networks are widely used, but their characteristics do not offer the level of performance required to carry high quality video under certain circumstances. Data transmission is always subject to errors on line. In the case of streaming, correction is attempted at destination, while on transfer of files, retransmissions of information are conducted and a reliable copy of the file is obtained. In the latter case, reception time is penalized because of the low priority this type of traffic on the networks usually has. While in streaming, image quality is adapted to line speed, and line errors result in a decrease of quality at destination, in the file copy the difference between coding speed vs line speed and errors in transmission are reflected in an increase of transmission time. The way news or audiovisual programs are transferred from a remote office to the production centre depends on the time window and the type of line available; in many cases, it must be done in real time (streaming), with the resulting image degradation. The main purpose of this work is the workflow optimization and the image quality maximization, for that reason a transmission model for multimedia files adapted to JPEG2000, is described based on the combination of advantages of file transmission and those of streaming transmission, putting aside the disadvantages that these models have. The method is based on two patents and consists of the safe transfer of the headers and data considered to be vital for reproduction. Aside, the rest of the data is sent by streaming, being able to carry out recuperation operations and error concealment. Using this model, image quality is maximized according to the time window. In this paper, we will first give a briefest overview of the broadcasters requirements and the solutions with IP networks. We will then focus on a different solution for video file transfer. We will take the example of a broadcast center with mobile units (unidirectional video link) and regional headends (bidirectional link), and we will also present a video file transfer file method that satisfies the broadcaster requirements.

Optically programmable logic cells as basic units for transmission and synchronization of chaotic signals

We proposed an optical communications system, based on a digital chaotic signal where the synchronization of chaos was the main objective, in some previous papers. In this paper we will extend this work. A way to add the digital data signal to be transmitted onto the chaotic signal and its correct reception, is the main objective. We report some methods to study the main characteristics of the resulting signal. The main problem with any real system is the presence of some retard between the times than the signal is generated at the emitter at the time when this signal is received. Any system using chaotic signals as a method to encrypt need to have the same characteristics in emitter and receiver. It is because that, this control of time is needed. A method to control, in real time the chaotic signals, is reported.