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Abstract: We report measurements of the transverse diffusion of electrons in P-10 gas (90% Ar, 10% CH4) in a laboratory-scale time projection chamber (TPC) utilizing a novel pixelated signal capture and digitization technique known as Q-Pix. The Q-Pix method incorporates a precision switched integrating transimpedance amplifier whose output is compared to a threshold voltage. Upon reaching the threshold, a comparator sends a 'reset' signal, initiating a discharge of the integrating capacitor. The time difference between successive resets is inversely proportional to the average current at the pixel in that time interval, and the number of resets is directly proportional to the total collected charge. We developed a 16-channel Q-Pix prototype fabricated from commercial off-the-shelf components and coupled them to 16 concentric annular anode electrodes to measure the spatial extent of the electron swarm that reaches the anode after drifting through the uniform field of the TPC. The swarm is produced at a gold photocathode using pulsed UV light. The measured transverse diffusion agrees with simulations in PyBoltz across a range of operating pressures (200–1500 Torr). These results demonstrate that a Q-Pix readout can successfully reconstruct the ionization topology in a TPC.

The aim of this paper was to evaluate the factors that predict regression of untreated CIN 2 and 3. A total of 93 patients with colposcopic persistent CIN 2 and 3 lesions after biopsy were followed for 6 months. Human papillomavirus (HPV) types were determined by polymerase chain reaction at enrolment. We analysed the biologic and demographic predictors of natural regression using univariate and multivariate methods. The overall regression rate was 52% (48 out of 93), including 58% (22 out of 38) of CIN 2 and 47% (26 out of 55) of CIN 3 lesions (P=0.31 for difference). Human papillomavirus was detected in 84% (78 out of 93) of patients. In univariate analysis, 80% (12 out of 15) of lesions without HPV regressed compared to 46% (36 out of 78) of lesions with HPV infection (P=0.016). Women without HPV and those who had a resolution of HPV had a four-fold higher chance of regression than those with persistent HPV (relative odds=3.5, 95% CI=1.4-8.6). Women with five or fewer lifetime sexual partners had higher rates of regression than women with more than five partners (P=0.003). In multivariate analysis, HPV status and number of sexual partners remained as significant independent predictors of regression. In conclusion, HPV status and number of lifetime sexual partners were strongly predictive of regression of untreated CIN 2 and 3.

To evaluate the effect of daily beta-carotene (30 mg) versus placebo over a 2-year period on cervical intraepithelial neoplasia (CIN) 2 and 3 lesions. Human papillomavirus (HPV) typing was done to determine whether lesion regression was related to HPV. Micronutrient levels were measured to determine whether levels were predictive of regression. Variables that influence the risk of HPV infection and CIN, such as cigarette smoking and sexual behavior, were evaluated. Women were randomized to beta-carotene or placebo, with cytology and colposcopy every 3 months. Cervical biopsies were performed before treatment and after 6 and 24 months to evaluate response. Persistence of or progression to CIN 3 resulted in removal from the study, whereas treatment continued for 2 years on all others. The presence and type of HPV was determined by PCR. Response was defined as an improvement in CIN by 2 grades. Mantel-Haenszel chi(2) test was used to analyze response to treatment. Fisher's exact test was used to determine the effect of HPV and CIN grade on response Wilcoxon's rank-sum tests were used to compare micronutrient levels between groups. Twenty-one of 124 enrolled women were not randomized because they either moved, became pregnant, voluntarily withdrew, or the pathological review of their initial cervical biopsies did not confirm CIN 2 or 3. Of the remaining 103 women, 33 experienced lesion regression, 45 had persistent or progressive disease, and 25 women did not complete the study and were considered nonresponders in the final analysis. The overall regression rate (32%) was similar between treatment arms and when stratified for CIN grade. Data on 99 women with HPV typing showed that 77% were HPV-positive and 23% HPV-negative at enrollment. HPV-positive lesions were subdivided into indeterminate-, low-, and high-risk categories; the response rate was highest for women with no HPV detected (61%), lower for indeterminate/low-risk (30%), and lowest for high-risk (18%; P =.001). CIN regression was negatively correlated with retinol levels. In conclusion, beta-carotene does not enhance the regression of high-grade CIN, especially in HPV-positive subjects.

The modern Eastern Equatorial Pacific (EEP) Ocean is a large oceanic source of carbon to the atmosphere (1). Primary productivity over large areas of the EEP is limited by silicic acid and iron availability, and because of this constraint the organic carbon export to the deep ocean is unable to compensate for the outgassing of carbon dioxide that occurs through upwelling of deep waters. It has been suggested that the delivery of dust-borne iron to the glacial ocean (2,3) could have increased primary productivity and enhanced deep-sea carbon export in this region, lowering atmospheric carbon dioxide concentrations during glacial periods. Such a role for the EEP is supported by higher organic carbon burial rates documented in underlying glacial sediments (4,5), but lower opal accumulation rates cast doubts on the importance of the EEP as an oceanic region for significant glacial carbon dioxide drawdown (6,7). Here we present a new silicon isotope record that suggests the paradoxical decline in opal accumulation rate in the glacial EEP results from a decrease in the silicon to carbon uptake ratio of diatoms under conditions of increased iron availability from enhanced dust input. Consequently, our study supports the idea of an invigorated biological pump in this region during the last glacial period that could have contributed to glacial carbon dioxide drawdown. Additionally, using evidence from silicon and nitrogen isotope changes, we infer that, in contrast to the modern situation, the biological productivity in this region is not constrained by the availability of iron, silicon and nitrogen during the glacial period. We hypothesize that an invigorated biological carbon dioxide pump constrained perhaps only by phosphorus limitation was a more common occurrence in low-latitude areas of the glacial ocean., The EEP is an important area of biogenic opal production and burial in the ocean (8), accounting for two-thirds of the marine carbon dioxide efflux to the atmosphere today (1). [...]

Abstract Given the massive and growing environmental impacts of conventional agriculture, humanity needs new methods for growing food that not only meet dietary needs but also provide for multiple ecosystem functions with potential benefits to people and biodiversity. Concepts from ecology and complex adaptive systems suggest that persistent structural heterogeneity and functional diversity are key for supporting biodiversity, ecosystem services, and resilience, but these concepts have not been extensively applied in agriculture, which is still dominated by annual monocropping systems. Perennial agriculture seems to embody these ecological concepts—particularly perennial polycultures that combine a variety of long‐lived woody perennial food crops with continuous ground cover. However, our understanding of the benefits and trade‐offs of such systems compared to conventional agriculture is limited, especially in temperate climates. Here, we provide a systematic and comprehensive study of the ecological attributes of 14 woody perennial polyculture farm fields to conventional annual and hay fields in the U.S. Midwest, one of the most industrialized food‐producing regions in the world. We found that perennial fields had (1) more diverse soil fungal, invertebrate, plant, and bird communities but found no difference in soil bacterial communities; (2) less compacted soil; (3) denser ground cover; (4) more active carbon, organic carbon, and nitrogen and the same available phosphorus in the top layer of soil; and (5) more species of predatory, detritivorous, and herbivorous insects, and approximately fourfold higher abundance of herbivorous insects. Food production from the oldest half of perennial fields was only 14.7% of a regional corn/soy rotation by weight, but increased with the age of the perennial field and had high nutritional diversity. Together, these findings indicate that woody perennial polyculture fields in the U.S. Midwest are characterized by higher biodiversity and ecosystem functions than adjacent conventional fields. Woody perennial polycultures in the temperate north might play a role in the transition of agricultural landscapes toward sustaining both people and nature over the long term.

The posteromedial cortices and other regions of the "default network" are particularly vulnerable to the pathology of Alzheimer disease (AD). In this study, we performed functional magnetic resonance imaging (fMRI) to investigate whether the presence of apolipoprotein E (APOE) epsilon allele and degree of memory impairment were associated with the dysfunction of these brain regions. Seventy-five elderly subjects ranging from cognitively normal to mild AD, divided into epsilon carriers and noncarriers, underwent fMRI during a memory-encoding task. Across all subjects, posteromedial and ventral anterior cingulate cortices (key components of the default network) as well as right middle and inferior prefrontal regions demonstrated reduced task-induced deactivation in the epsilon carriers relative to noncarriers. Even among cognitively normal subjects, epsilon carriers demonstrated reduced posteromedial deactivation compared with the noncarriers in the same regions which demonstrated failure of deactivation in AD patients. Greater failure of posteromedial deactivation was related to worse memory performance (delayed recall) across all subjects and within the range of cognitively normal subjects. In summary, the posteromedial cortical fMRI response pattern is modulated both by the presence of APOE epsilon and episodic memory capability. Altered fMRI activity of the posteromedial areas of the brain default network may be an early indicator of risk for AD. [ABSTRACT FROM AUTHOR]

Non-sequential double ionization (NSDI) using phase-stabilised few-cycle laser pulses is investigated. We report differential measurements of Ar++ ion momentum distributions. They show a strong dependence on the carrier-envelope (CE) phase. Via control over the CE phase one is able to direct the NSDI dynamics. Data analysis through a classical model calculation reveals that the influence of the optical phase enters via: (1) the cycle-dependent electric field ionization rate, (2) the electron recollision time and (3) the accessible phase space for inelastic collisions. Our model indicates that the combination of these effects allows a look into single-cycle dynamics already for few-cycle pulses. [ABSTRACT FROM AUTHOR]

We conducted a study using mixed methods to explore implementation of reform legislation and related outcomes for students with disabilities and those placed at risk of school failure. Designed to promote equal educational opportunities, the legislation included provisions for (a) redistributing state funding so that schools would have more equal access to resources and (b) requiring all schools to adopt and use state standards and standards-based assessments. Almost one fourth of the public schools in the state participated in the study, including schools that gained, lost, or were not affected by the redistribution of state education funds. A cross-case analysis identified both benefits and challenges for students with disabilities and those placed at risk of school failure, suggesting a need to ensure that reforms focus on outcomes for all students and include adequate resources and professional development opportunities for educators and administrators in both general and special education. [ABSTRACT FROM AUTHOR]

Objective: Our purpose was to increase our understanding of the clinical significance of atypical glandular cells of undetermined origin.Study Design: All cytologic Papanicolaou smears were reviewed and classified within the context of the Bethesda classification system. Charts of all patients with a diagnosis of atypical glandular cells of undetermined origin were reviewed for previous medical history, diagnostic study, histologic diagnosis, and prior Papanicolaou smear abnormalities.Results: The incidence of atypical glandular cells of undetermined origin in 76,018 Papanicolaou smears was 0.196%. We reviewed 133 patient medical records with cytologic diagnoses. Eighty of these patients have had appropriate follow-up. Thirty-six (45%) of these were found to have significant histologic abnormalities, including 6 patients with cervical intraepithelial neoplasia, grades 2 and 3, and 4 invasive cancers.Conclusion: The frequency of underlying serious histologic changes is much greater in atypical glandular cells than in atypical squamous cells of undetermined significance. On the basis of our results, we believe that all patients with atypical glandular cells should undergo intensive evaluation including colposcopy, cervical biopsy, and endocervical curettage. When diagnosis cannot be clearly established, patient should undergo endometrial biopsy. [ABSTRACT FROM AUTHOR]

The aims of this study were: (i) to quantify near-infrared optical properties of normal cervical tissues and high-grade squamous intra-epithelial lesions (H-SIL); (ii) to assess the feasibility of differentiating normal cervical tissues from H-SIL on the basis of these properties; and (iii) to determine how cervical tissue optical properties change following photodynamic therapy (PDT) of H-SIL in vivo. Using the frequency domain photon migration technique, non-invasive measurements of normal and dysplastic ecto-cervical tissue optical properties, i.e. absorption (mu(a)) and effective scattering coefficients, and physiological parameters, i.e. tissue water and haemoglobin concentration, percentage oxygen saturation (%SO(2)), were performed on 10 patients scheduled for PDT of histologically-proven H-SIL. Cervix absorption and effective scattering parameters were up to 15% lower in H-SIL sites compared with normal cervical tissue for all wavelengths studied (674, 811, 849, 956 nm). Following PDT, all mu(a) values increased significantly, due to elevated tissue blood and water content associated with PDT-induced hyperaemia and oedema. Tissue total haemoglobin concentration ([TotHb]) and arterio-venous oxygen saturation measured in H-SIL sites were lower than normal sites ([TotHb]: 88.6 +/- 35.8 micromol/l versus 124.7 +/- 22.6 micromol/l; %SO(2): 76.5 +/- 14.7% versus 84.9 +/- 3.4%). [ABSTRACT FROM AUTHOR]