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1.
Nat Commun ; 13(1): 2058, 2022 04 19.
Article in English | MEDLINE | ID: mdl-35440543

ABSTRACT

Extreme rainfall events in the humid-tropical Luquillo Mountains, Puerto Rico export the bulk of suspended sediment and particulate organic carbon. Using 25 years of river carbon and suspended sediment data, which targeted hurricanes and other large rainstorms, we estimated biogenic particulate organic carbon yields of 65 ± 16 tC km-2 yr-1 for the Icacos and 17.7 ± 5.1 tC km-2 yr-1 for the Mameyes rivers. These granitic and volcaniclastic catchments function as substantial atmospheric carbon-dioxide sinks, largely through export of river biogenic particulate organic carbon during extreme rainstorms. Compared to other regions, these high biogenic particulate organic carbon yields are accompanied by lower suspended sediment yields. Accordingly, particulate organic carbon export from these catchments is underpredicted by previous yield relationships, which are derived mainly from catchments with easily erodible sedimentary rocks. Therefore, rivers that drain petrogenic-carbon-poor bedrock require separate accounting to estimate their contributions to the geological carbon cycle.


Subject(s)
Carbon , Rivers , Carbon/analysis , Carbon Cycle , Environmental Monitoring , Forests , Puerto Rico
2.
Phys Rev Lett ; 118(25): 251301, 2017 Jun 23.
Article in English | MEDLINE | ID: mdl-28696731

ABSTRACT

New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41} cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.

3.
Phys Rev Lett ; 114(23): 231302, 2015 Jun 12.
Article in English | MEDLINE | ID: mdl-26196790

ABSTRACT

New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of <3.5×10(-10) and an alpha rejection factor of >98.2%. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.


Subject(s)
Fluorocarbons/chemistry , Models, Theoretical , Acoustics/instrumentation , Algorithms , Neutrons
4.
BJOG ; 115(4): 509-14, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18271888

ABSTRACT

OBJECTIVE: Vulval pain, in the absence of pathology, may have a psychological basis that relates to life events. This study aimed to determine the nature of such events. DESIGN: Structured questionnaire about patient's symptoms and early-life events. SETTING: Private practice physiotherapist specialising in pelvic floor disorders. POPULATION: Patients with vulvodynia as their primary symptom and control patients being treated for urinary tract disorder or post-childbirth routine physiotherapy who had no vulval pain on direct questioning. METHODS: Questionnaire applied to consecutive patients referred for treatment. Seventy-eight consecutive women presenting with vulvodynia (mean age 34 years, mean duration of symptoms 48 months) and 78 controls (mean age 39 years). MAIN OUTCOME MEASURES: Incidence of life events. RESULTS: A similar proportion of both groups were married. Being in a new relationship (P < 0.04), adverse current or previous relationships (39 versus 9%, P < or = 0.01), parental divorce (26 versus 9%, P < or = 0.001), history of termination of pregnancy, and adverse childbirth experiences (P < 0.04) were more common in patients than in controls. A history of sexual abuse was not more common in patients with vulvodynia compared with controls (13 versus 10%, P = not significant). Lack of libido was common in patients with vulvodynia (94 versus 29%, P < 0.0001). CONCLUSIONS: Adverse life experiences, including conflict, are common in women with vulvodynia. These factors may be important in mediating the genesis of pain through stress-related mechanisms. Sexual interest is diminished in these women. Sexual abuse is not a factor in most of these women. These findings have implications for treatment.


Subject(s)
Life Change Events , Pain/psychology , Vulvar Diseases/psychology , Adult , Child , Child Abuse/psychology , Domestic Violence/psychology , Family Relations , Female , Humans , Marital Status , Parity , Pregnancy , Sexual Partners
6.
Proc Biol Sci ; 267(1459): 2239-45, 2000 Nov 22.
Article in English | MEDLINE | ID: mdl-11413638

ABSTRACT

Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences.


Subject(s)
Facial Expression , Adolescent , Adult , Drama , Female , Humans , Japan , Male , Middle Aged , Visual Perception
8.
Pediatr Nephrol ; 11(5): 542-6, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9323276

ABSTRACT

The purpose of the present study was to assess the effect of intelligence, schooling, psychomotor, emotional, and social status on renal graft survival in children. Sixty-two cadaver renal transplant recipients were evaluated retrospectively and the influence of sex, age, weight, and the use of cyclosporin A (CyA) on the success rate of the graft from 1 to 5 years later was analyzed. Psychological and social scores were devised and included as factors predictive of survival of the graft. Univariate analysis showed that the following variables predicted renal graft survival: the use of CyA (P = 0.0002), pre-transplant dialysis (P = 0.04), weight at the time of transplantation (P = 0.072), and psychological scores (P = 0.064). Association analysis demonstrated that pre-transplantation dialysis was only a chance association and therefore the parameter was discarded. Multivariate analysis showed that the predictive parameters were the use of CyA, sex, weight in kilograms, and the psychological score. An equation was then derived from variables that predict the probability that a specific patient's graft will survive more than t months. This equation is the estimated survival distribution function and is as follow: S (t) = Exp {-Exp[-(0.8882x1 - 1.827x2 + 0.037x3 - 0.1746x4) + ln t - 4.7862]} where S (t) = the survival at t months post transplantation, x1 = sex (male 1, female 2), x2 = CyA (yes 1, no 2), x3 = weight in kilograms, and x4 = psychological score. The major impact of psychological factors on renal graft survival was surprising.


Subject(s)
Graft Survival , Kidney Failure, Chronic/therapy , Kidney Transplantation/statistics & numerical data , Social Environment , Adolescent , Child , Child Development/physiology , Child, Preschool , Cyclosporine/therapeutic use , Female , Humans , Immunosuppressive Agents/therapeutic use , Infant , Intelligence/physiology , Kidney Failure, Chronic/psychology , Male , Multivariate Analysis , Psychological Tests , Schools , Sex Characteristics , Socioeconomic Factors
9.
J Learn Disabil ; 30(4): 365-75, 1997.
Article in English | MEDLINE | ID: mdl-9220704

ABSTRACT

This study examined the effects of overt phonologic impairment (disordered speech) on phonological awareness, verbal working memory, and letter knowledge. Forty-five children--29 with moderate to severe productive phonologic impairment at the inception of the project and 16 without impairment--were followed from mean age 3-6 to age 6-0. Fifteen participants with impairment were matched on gender and mental age to 15 without impairment for certain aspects of the analysis. The children with phonologic impairment performed significantly worse than their controls on tasks of verbal working memory, phoneme segmentation, and letter identification. In addition, a path analysis revealed working memory to be a potentially important mediating variable. The investigators also measured productive syntax, which, although associated with productive phonology and working memory, was not associated with letter identification.


Subject(s)
Memory , Phonetics , Reading , Speech Disorders/psychology , Case-Control Studies , Child , Child, Preschool , Female , Humans , Longitudinal Studies , Male , Regression Analysis , Speech Disorders/complications , Speech Perception , Verbal Learning
10.
Can Nurse ; 92(8): 42-6, 1996 Sep.
Article in French | MEDLINE | ID: mdl-9095727

ABSTRACT

The direction that health care has taken in the past few years indicates an urgent need for new models of thinking and new interventions in health care institutions. Despite all of the changes, the nurse remains the one social being the patient can rely on for interpersonal relationships. Can the art of caring, which is at the root of nursing, survive present-day economic pressures? Is it still a useful, accessible and important tool for therapeutic contact? This article, written as a testimonial, gives the author's insights, examples and a short case history on the subject of caring. The author discusses organizational frameworks of health care institutions and encourages readers to review their own nursing practice as a means of improving within their own institutions. Key elements of caring such as altruistic values, sensibility to oneself and others, and the trust-hope relationship are presented. The author's objective is to invite further discussion and promote awareness of the threat to the art of caring.


Subject(s)
Empathy , Health Care Reform/organization & administration , Models, Nursing , Altruism , Humans , Organizational Innovation
11.
Appl Opt ; 35(15): 2595-601, 1996 May 20.
Article in English | MEDLINE | ID: mdl-21085403

ABSTRACT

A self-referencing technique compensating for fiber losses and source fluctuations in reflective air-gap intensity-based optical fiber sensors is described. A dielectric multilayer short-wave-pass filter is fabricated onto or attached to the output end face of the lead-in-lead-out multimode fiber. The incoming broadband light from a white light or a light-emitting diode is partially reflected at the filter. The transmitted light through the filter projects onto a mirror. The light returning from the reflecting mirror is recoupled into the lead-in-lead-out fiber. These two reflections from the filter and the reflecting mirror are spectrally separated at the detector end. The power ratio of these two reflections is insensitive to source fluctuations and fiber-bending loss. However, because the second optical signal depends on the air-gap separation between the end face of the lead-in-lead-out fiber and the reflecting mirror, the ratio provides the information on the air-gap length. A resolution of 0.13 µm has been obtained over a microdisplacement measurement range of 0-254 µm. The sensor is shown to be insensitive to both fiber-bending losses and variations in source power. Based on this approach, a fiber-strain sensor was fabricated with a multilayer interference filter directly fabricated on the end face of the fiber. A resolution of 13.4 microstrain was obtained over a measurement range of 0-20,000 microstrain with a gauge length of 10 mm. The split-spectrum method is also incorporated into a diaphragm displacement-based pressure sensor with a demonstrated resolution of 450 Pa over a measurement range of 0-0.8 MPa.

14.
Can Nurse ; 91(6): 40-3, 1995 Jun.
Article in French | MEDLINE | ID: mdl-7780936

ABSTRACT

Several nursing studies have described the important role of the oncology nurse manager in managing nursing staff. A 1987 study by Vachon, outlined stressors identified by 581 health professionals working in oncology units. It identified the fact that nursing personnel face a workplace filled with pain and suffering on a daily basis. The study concluded that the oncology nurse manager is the key individual to encourage a climate of sharing and support among nursing staff. Oncology nurse managers are role models and mentors who transmit to their staff the desire for a caring and holistic approach to excellence in patient care. Professional, educational and personal responsibilities rest with them. They must maintain a dynamic presence with all members of the health care team. Their knowledge of the most current medical breakthroughs, as well as strong leadership qualities, inspire nursing staff to strive for high standards of care.


Subject(s)
Nursing, Supervisory/organization & administration , Oncology Nursing/organization & administration , Humans , Job Description , Mentors , Nursing Staff, Hospital/education , Nursing Staff, Hospital/psychology
17.
Percept Mot Skills ; 75(3 Pt 2): 1195-204, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1484787

ABSTRACT

In this study were compared the phonological awareness of 15 moderately to severely phonologically impaired and 15 phonologically normal children, matched on mental age and gender, on sensitivity to alliteration and to rhyme. Analysis showed no significant difference between the groups in detection of alliteration; however, there was a significant difference in detection of rhyme. The latter correlated .43 with speech intelligibility. We conclude that phonological awareness is associated closely with productive phonological ability early in development.


Subject(s)
Cognition , Phonetics , Reading , Child, Preschool , Female , Humans , Male , Risk Factors , Speech
18.
Ann Physiol Anthropol ; 11(6): 631-4, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1476564

ABSTRACT

The detection of dampness in hygroscopic materials has been investigated both by subjective tests and by the application of a model of the physical mechanisms involved. Subjects were asked to rate the degree of dampness of a range of materials of different moisture contents after a short period of contact with the inner forearm. Skin and fabric inner surface temperatures were recorded. It was found that highly hygroscopic wool fabrics were perceived as being dryer and maintained a higher temperature at the skin surface than polyester, a less hygroscopic fabric, during fabric-skin contact. A physical model of the sorption/desorption process in hygroscopic materials has been developed from knowledge of fibre sorption kinetics and used to study the physical processes which take place at the skin-fabric interface during transient contact. These predictions agree well with the subjective responses and the measured temperatures.


Subject(s)
Perception/physiology , Polyesters , Skin Physiological Phenomena , Wool , Adult , Animals , Humans , Skin Temperature , Wettability
20.
Can Nurse ; 86(7): 31-4, 1990 Aug.
Article in French | MEDLINE | ID: mdl-2376043

ABSTRACT

Convinced that many physical ailments are directly linked to an emotional problem, the authors provide an in-depth explanation of somatic illness and the various methods of treating it. They outline the roles and responsibilities of nurses working in a multidisciplinary context.


Subject(s)
Psychophysiologic Disorders/nursing , Family , Humans , Personality , Physician-Patient Relations , Psychophysiologic Disorders/diagnosis
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