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The Dark Matter Time Projection Chamber collaboration recently reported a dark matter
limit obtained with a 10 liter time projection chamber filled with CF4 gas. The
10 liter detector was capable of 2D tracking (perpendicular to the drift direction) and 2D
fiducialization, and only used information from two CCD cameras when identifying tracks
and rejecting backgrounds. Since that time, the collaboration has explored the potential
benefits of photomultiplier tube and electronic charge readout to achieve 3D tracking, and
particle identification for background rejection. The latest results of this effort is
Over the past few decades, theory and research on depression have increasingly focused on the recurrent and chronic nature of the disorder. These recurrent and chronic forms of depression are extremely important to study, as they may account for the bulk of the burden associated with the disorder. Paradoxically, however, research focusing on depression as a recurrent condition has generally failed to reveal any useful early indicators of risk for recurrence. We suggest that this present impasse is due to the lack of recognition that depression can also be an acute, time-limited condition. We argue that individuals with acute, single lifetime episodes of depression have been systematically eclipsed from the research agenda, thereby effectively preventing the discovery of factors that may predict who, after experiencing a first lifetime episode of depression, goes on to have a recurrent or chronic clinical course. Greater awareness of the high prevalence of people with a single lifetime episode of depression, and the development of research designs that identify these individuals and allow comparisons with those who have recurrent forms of the disorder, could yield substantial gains in understanding the lifetime pathology of this devastating mental illness.
Practical values to guide food choices for control of postprandial glycaemia need to refer to entire foods in amounts customarily consumed. We tested an in vitro method for determining the relative glycaemic impact (RGI) of customarily consumed portions of foods. Sugars released during in vitro pancreatic digestion of eighty-three foods were measured as glucose equivalents (GE) per gram of food, adjusted by the glycaemic indexes of the sugars to obtain glycaemic GE (GGE) per gram and multiplied by food portion weight to obtain the GGE contribution of the food portion, its RGI. The results were compared with clinical GGE values from subjects who consumed the same food amounts. In vitro and in vivo GGE values were significantly correlated, but the slope of the regression equation was significantly less than one, meaning in vitro GGE values overestimated in vivo GGE values. Bland–Altman method comparison showed the in vitro–in vivo disparity to increase as mean GGE increased, suggesting the need to allow for different rates of homeostatic blood glucose disposal (GD) due to different GGE doses in the customarily consumed food portions. After GD correction, Bland–Altman method comparison showed that the bias in predicting in vivo GGE values from in vitro GGE values was almost completely removed (y = 0·071x − 0·89; R2 0·01). We conclude that in vitro food values for use in managing the glycaemic impact of customarily consumed food quantities require correction for blood GD that is dependent on the GGE content of the food portions involved.
Cognitive behaviour therapy (CBT) has been shown to reduce psychological morbidity in people with cancer, but no randomized controlled trial (RCT) exists in palliative care. We aimed to determine whether home care nurses could be taught to deliver basic cognitive behavioural techniques and so reduce symptoms of anxiety and depression.
Clinical nurse specialists (CNSs) at St Christopher's Hospice were randomly allocated to receive training in CBT or continue their usual practice. At the end of the trial, nurses were rated on the Cognitive Therapy First Aid Rating Scale (CTFARS) for CBT competence. Home care patients who scored as possible cases on the Hospital Anxiety and Depression Scale (HADS) entered the trial. Participants received home care nursing visits. Assessments were carried out at baseline, 6, 10 and 16 weeks.
Eight nurses received CBT training and seven continued practice as usual. The mean CTFARS scores were 35.9 for the CBT nurses and 19.0 for the controls (p=0.02). A total of 328 patients (54%) were possible cases and 80 entered the trial; most of those excluded were too ill to participate. There was an interaction between group and time: individuals receiving CBT had lower anxiety scores over time [coefficient −0.20, 95% confidence interval (CI) −0.35 to −0.05, p=0.01]. No effect of the training was found for depression.
It is possible to conduct a randomized trial of psychological interventions in palliative care but there is considerable attrition from physical morbidity and mortality. Nurses can learn to integrate basic CBT methods into their clinical practice. This training may be associated with better outcomes for symptoms of anxiety.
Comparative and functional fungal genomics
S. E. Baker, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
C. F. Wend, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
D. Martinez, Genome Annotation and Analysis Joint Genome Institute Los Alamos National Laboratory Los Alamos NM 87545 USA,
J. K. Magnuson, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
E. A. Panisko, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
Z. Dai, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
K. S. Bruno, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA,
K. K. Anderson, Decision & Sensor Analytics Pacific Northwest National Laboratory 906 Battelle Blvd. Richland WA 99352 USA,
M. E. Monroe, Biological Separations and Mass Spectrometry Pacific Northwest National Laboratory 3335 Q Avenue Richland WA 99352 USA,
D. S. Daly, Statistical Sciences Pacific Northwest National Laboratory 3180 George Washington Way Richland WA 99352 USA,
L. L. Lasure, Fungal Biotechnology Team MSIN: K2–12 Chemical and Biological Processes Development Group Pacific Northwest National Laboratory 902 Battelle Blvd. Richland WA 99352 USA
In order to decrease dependence on petroleum, the United States Department of Energy (USDOE) Office of the Biomass Program (OBP) is investing in research and development to enable its vision of the biorefinery. The biorefinery will decrease the use of petroleum through conversion of biomass such as crops or agricultural waste into fuels and products.
In 2004, the USDOE OBP asked researchers at the Pacific Northwest National Laboratory (PNNL) and the National Renewable Energy Laboratory (NREL) to prepare a list of the top ten building-block chemicals that can be derived from simple sugars by biological and/or chemical means. The resulting list of twelve building-block chemicals and the accompanying report (www.eere.energy.gov/biomass/pdfs/35523.pdf) form an informational foundation on which future DOE and industry bioproducts research will be built (Table 1.1).
How do fungi fit into the biorefinery? Analysis of the ‘top ten’ study indicates that nine of the top twelve chemical building blocks are currently produced, or may potentially be produced, by fungal fermentation processes. However, a significant barrier to the use of bio-based products is the economic feasibility – fuels and products must be price-competitive with those derived from petroleum. An obvious way to decrease the costs of biobased products from fungi is to make fermentation strains more productive and processes more efficient. Traditional strain improvement programmes typically span a timescale measured in decades and process development done through the use of batch cultures is extremely labour intensive.
On 3 February 2004, the Vermont Department of Health received reports of acute gastroenteritis in persons who had recently visited a swimming facility. A retrospective cohort study was conducted among persons attending the facility between 30 January and 2 February. Fifty-three of 189 (28%) persons interviewed developed vomiting or diarrhoea within 72 h after visiting the facility. Five specimens tested positive for norovirus and three specimen sequences were identical. Entering the smaller of the two pools at the facility was significantly associated with illness (RR 5·67, 95% CI 1·5–22·0, P=0·012). The investigation identified several maintenance system failures: chlorine equipment failure, poorly trained operators, inadequate maintenance checks, failure to alert management, and insufficient record keeping. This study demonstrates the vulnerability of recreational water to norovirus contamination, even in the absence of any obvious vomiting or faecal accident. Our findings also suggest that norovirus is not as resistant to chlorine as previously reported in experimental studies. Appropriate regulations and enforcement, with adequate staff training, are necessary to ensure recreational water safety.
Covering an area of 177,000 hectares, the region known within Belize as the Chiquibul Forest comprises the country's largest forest reserve and includes the Chiquibul Forest Reserve, the Chiquibul National Park and the Caracol Archaeological Reserve. Based on 7047 herbarium and live collections, a checklist of 1355 species of vascular plant is presented for this area, of which 87 species are believed to be new records for the country. Of the 41 species of plant known to be endemic to Belize, four have been recorded within the Chiquibul, and 12 species are listed in The World Conservation Union (IUCN) 2006 Red List of Threatened Species. Although the Chiquibul Forest has been relatively well collected, there are geographical biases in botanical sampling which have focused historically primarily on the limestone forests of the Chiquibul Forest Reserve. A brief review of the collecting history of the Chiquibul is provided, and recommendations are given on where future collecting efforts may best be focused. The Chiquibul Forest is shown to be a significant regional centre of plant diversity and an important component of the Mesoamerican Biological Corridor.
We sought to determine the source of a norovirus outbreak among attendees of 46 weddings taking place during a single weekend. Norovirus-compatible illness was experienced by 332 (39%) of wedding guests surveyed; the outbreak affected up to 2700 persons. Illness was associated with eating wedding cake provided by a bakery common to the weddings (adjusted RR 4·5, P<0·001). A cake requiring direct hand contact during its preparation accounted for the majority of illness. At least two bakery employees experienced norovirus-compatible illness during the week preceding the weddings. Identical sequence types of norovirus were detected in stool specimens submitted by two wedding guests, a wedding hall employee, and one of the ill bakery employees. It is likely that one or more food workers at the bakery contaminated the wedding cakes through direct and indirect contact. These findings reinforce the necessity of proper food-handling practices and of policies that discourage food handlers from working while ill.
We describe our strategies and results in the preparation of supramolecularly ordered ultrathin films of DNA assemblies using the layer-by-layer (LbL) alternate polyelectrolyte adsorption technique. The properties of DNA are intimately associated with their polyelectrolyte behavior in solution. Deposition at interfaces is governed by conformation, orientation, and charge density of these biomolecules in relation to the physisorption phenomena in oppositely charged surfaces. Thus, controlling the nature of surfaces (polymer charge density, ionic strength, other non-covalent interactions, etc.) is important in modifying the adsorption phenomena. In this work, differences in adsorption and incorporation of DNA with dyes, linear polymers and dendrimers are highlighted. A number of surface sensitive spectroscopic and microscopic techniques were used to probe the adsorption and multilayer assembly phenomena, e.g. surface plasmon resonance spectroscopy (SPS), AFM, quartz crystal microbalance (QCM) and ellipsometry. These studies are important for future applications such as the use of polycations as non-viral gene transfection vectors for drug-delivery and DNA adsorption on microarray surfaces. By combining with the alternate assembly of azobenzene and phthalocyanine dyes, we have been able to prepare optobiolelectronic substrates where the phenomena of irradiation and electrochemistry can be used to probe the ordering and response of these films.
To assess possible transmission modes of, and risk factors for, gastroenteritis associated with Norwalk-like viruses (NLVs) in a geriatric long-term-care facility.
During a prolonged outbreak of acute gastroenteritis, epidemiological data on illness among residents and employees were collected in conjunction with stool, vomitus, and environmental specimens for viral testing. NLVs were identified by electron microscopy in stool and vomitus specimens, and further characterized by reverse-transcriptase polymerase chain reaction and nucleotide sequencing. Potential risk factors were examined through medical-record review, personal interview, and a self-administered questionnaire sent to all employees.
During the outbreak period, 52 (57%) of 91 residents and 34 (35%) of 90 employees developed acute gastroenteritis. Four case-residents were hospitalized; three residents died at the facility shortly after onset of illness. A point source was not identified; no association between food or water consumption and gastroenteritis was identified. A single NLV strain genetically related to Toronto virus was the only pathogen identified. Residents were at significantly higher risk of gastroenteritis if they were physically debilitated (relative risk [RR], 3.5; 95% confidence interval [CI95], 1.0-12.9), as were employees exposed to residents with acute gastroenteritis (RR, 2.6; CI95, 1.1-6.5) or ill household members (RR, 2.3; CI95, 1.4-3.6). Adherence to infection control measures among the nursing staff may have reduced the risk of gastroenteritis, but the reduction did not reach statistical significance.
In the absence of evidence for food-borne or waterborne transmission, NLVs likely spread among residents and employees of a long-term-care facility through person-to-person or airborne droplet transmission. Rapid notification of local health officials, collection of clinical specimens, and institution of infection control measures are necessary if viral gastroenteritis transmission is to be limited in institutional settings
Background. The stress generation hypothesis proposed
by Hammen (1991) holds that depressed
individuals generate stressful conditions for themselves, which lead to
recurrence. The original test
of this hypothesis compared dependent life events in women with recurrent
depression to medical
and normal controls. Two further research questions emerged from this work:
(a) do individuals
with a history of many depressive episodes generate more dependent life
events than depressives
with fewer episodes?; and (b) what is the aetiological relevance
of any stress that may be generated?
Methods. The present research tested differences in dependent
and independent events between
depressed individuals who had experienced: (a) no previous major
depressive episodes; (b) one
previous episode; and (c) two or more previous episodes. We predicted
that, based on the stress
generation hypothesis, recurrent depressives would show more dependent
events than people
without a depression history, and that these generated stressors would
be of aetiological importance
for precipitating recurrence (i.e. severe events in the 3 months preceding
Results. Recurrent depressives experienced significantly more
total dependent events than first-onset depressives in the 12 months, but
not the 3 months, preceding their episode.
Conclusions. Although the findings supported the general premise of stress
aetiological relevance of the generated stress for recurrence requires
An understanding of dielectric breakdown mechanisms is critical for continued oxide scaling. Although working transistors have been demonstrated with sub-2nm SiO2 gate dielectrics, the manufacturability of such devices hinges on the reliability of the oxide. As oxides become thinner and operating voltages become lower, a fundamentally different mode of dielectric breakdown occurs. This has been called soft breakdown and is considered to be the formation of a small, localized tunneling path through a dielectric. For transistors with 2-nm gate oxides, threshold voltage and maximum transconductance are not affected by soft breakdown, implying that circuits may continue to operate after soft breakdown. The increase in gate current or voltage noise associated with soft breakdown is not a limiting factor for many applications. However, some cases will be shown in which soft breakdown does degrade device function.
In order to make comparisons of ultra-thin oxide quality, it is important to be able to reliably detect soft breakdown. J-ramp, a commonly used ramped-current measurement to determine oxide quality, is unable to detect soft breakdown in ultra-thin oxides. We will demonstrate the incorporation of noise measurements in a commercial J-ramp algorithm.
Although food handlers are often implicated as the source of infection
in outbreaks of
food-borne viral gastroenteritis, little is known about the
timing of infectivity in relation to illness.
We investigated a gastroenteritis outbreak among employees of a manufacturing
found an association (RR=14·1, 95% CI=2·0–97·3)
between disease and eating sandwiches
prepared by 6 food handlers, 1 of whom reported gastroenteritis which had
subsided 4 days
earlier. Norwalk-like viruses were detected by electron microscopy or reverse
transcriptase-polymerase chain reaction (RT-PCR) in stool specimens from several company
sick food handler whose specimen was obtained 10 days after resolution
of illness, and an
asymptomatic food handler. All RT-PCR product sequences were identical,
common source of infection. These data support observations from recent
that current recommendations to exclude food handlers from work for 48–72
h after recovery
from illness may not always prevent transmission of Norwalk-like viruses
because virus can be
shed up to 10 days after illness or while exhibiting no symptoms.
Endemic and epidemic viral gastroenteritis are major causes of morbidity worldwide and are frequently a major cause of death in the developing world. Rotavirus, adenovirus, calicivirus, astrovirus, and the Norwalk virus family are the viruses most often associated with gastroenteritis. Of these, the major cause of epidemic viral gastroenteritis in the US is Norwalk-like viruses. Gastroenteritis caused by this virus group is responsible for such outbreaks in settings such as cruise ships, schools, camps, hospitals, day-care and extended care facilities, football games and festivals.
As early as the 1950s and 1960s electron microscopy (EM), including negative stain EM, was established as a diagnostic tool for identifying viruses. Negative stain EM is especially useful for identifying viruses that are difficult or impossible to culture (eg. viruses in the Norwalk family). The first Norwalk virus was identified in the 1969 by immune-negative stain EM. Many antigenic types were identified soon afterward that did not cross-react with the prototype Norwalk virus.
To identify the etiologic agent and risk factors associated with a hospital ward outbreak of gastroenteritis.
A regional referral hospital in upstate South Carolina.
We reviewed patient charts, surveyed staff, and tested stool from acutely ill persons. A case was defined as diarrhea and vomiting in a staff member or patient from January 5 to 13, 1996.
The initial case occurred on January 5 in a staff nurse who subsequently was hospitalized on the ward and visited by many staff colleagues. The staff were at a significantly greater risk for gastroenteritis than were patients (28/89 [31%] vs 10/91 [11%]; relative risk [RR], 2.9; 95% confidence interval [CI95], 1.5-5.5). All 10 case-patients had been exposed to case-nurses (assigned nurses who were primary caretakers), and eight had documented exposure to case-nurses 1 to 2 days before their illness. Patients exposed to case-nurses had a significantly increased risk of illness (8/57 [14%] vs 0/32; RR, >4.5; CI95, undefined). Neither staff nor patients had significantly increased risk from food, water, ice, or exposure to case-patients. Electron microscopy identified small round-structured viruses (SRSVs) in nine of nine stool samples.
This nosocomial outbreak of gastroenteritis was likely caused by SRSVs introduced by a staff member and spread via person-to-person transmission from and among staff. The potential for spread of SRSV-associated gastroenteritis from and among staff should be considered in developing strategies to prevent similar outbreaks in hospital settings
Molecular and immunologie assays for virus identification and characterization are well known for their high specificity and sensitivity. High specificity occasionally hampers efforts to detect virus strains distantly related to previously recognized types and may allow infectious agents to be undetected when these techniques are used for identification. We describe in this report such an example with an outbreak of foodborne gastroenteritis.
Forty-six cases of gastrointestinal illness were reported in May 1994 among adult staff of a Parkville, Md., school after a catered luncheon. Symptoms included stomach cramps, nausea, diarrhea, and vomiting. Seven stool specimens, negative by routine bacteriological screening, and 14 acute-and convalescent-phase sera from patients involved in the outbreak were tested for viruses. The stool specimens were examined by electron microscopy (EM) and reverse transcription-polymerase chain reaction (RT-PCR) designed to detect small round structured viruses (SRSVs). In addition, serum specimens were tested for IgG antibody to recombinant capsid proteins from Norwalk virus (rNV) and Toronto virus (rTV) using a direct enzyme immunoassay (EIA).
In May 1994, 43 persons in a nursing home were reported with gastroenteritis. An outbreak investigation was conducted to determine risk factors for gastroenteritis among residents and staff.
Data were analyzed using contingency tables; relative risks (RR) and statistical significance were determined with Fisher's Exact Test. The chi-squared statistic to perform a goodness of fit test for the binomial distribution was used to determine whether cases occurred randomly and independently of each other. Stools were tested for bacterial enteric pathogens, ova, and parasites and were examined by electron microscopy, Southern hybridization, and reverse transcription-polymerase chain reaction. Paired sera were collected to detect fourfold rises in antibody titer by enzyme immunoassay against Norwalk viruses.
Of 121 residents, 62 (51%) had gastroenteritis, as did 64 (47%) of the 136 staff. The index case was a nurse who became ill at work and continued to work, while symptomatic, for another 2 days. Only residents who had received medications from this nurse between May 17 and May 20 became ill on the first day of the outbreak (13 of 35 versus 0 of 5). Nurses and nurse aides were more likely than employees without direct resident contact to be cases (46 of 68 versus 18 of 58; RR, 2.18;P<.001). Bacterial stool cultures and parasite examinations were negative. Results of electron microscopy, polymerase chain reaction with Southern hybridization, and enzyme immunoassay indicated the causative agent was a small, round, structured virus similar to the Snow Mountain Agent.
To minimize outbreaks in nursing homes, we recommend that ill staff be excluded from work until symptoms resolve.
Astroviruses (AstV) and caliciviruses (CacV) are members of a group of 20-40nm infectious gastroenteric viruses. These viruses often have few distictive morphologic features and occur only in small numbers, making them difficult to detect by EM or serology. Specific antisera in animals or production of monoclonal antibodies has only recently been achieved for a few serotypes. The genomes of AstV (AstV genotype 2) and CacV (Toronto virus genotype) have recently been characterized. The complete genome of each virus consists of three open reading frames (ORF). ORF-2 of each virus codes for a capsid precursor. We have expressed capsid protein of each virus in Autographica califonica nuclear polyhedrosis virus (AcNPV) infected Spodoptera fruigiperda (Sf9) cells. Capsid protein precursors expressed in AcNPV-infected insect cells self-assembled into virus-like particles (VLPs) that were antigenic by immunofluorescence and enzyme-linked immunosorbent assays as well as immunogenic in laboratory animals. Purification of the VLPs was monitored by negative stain direct EM (2 % phosphotungstic acid pH 6.5 or 0.5% uranyl acetate) or by immune EM. AcNPV expressed preparations were examined by using monoclonal antibodies, anti sera raised in animals, or from humans previously infected with the respective AstV or CacV.