Estimating surface soil moisture from SMAP observations using a Neural Network technique

A Neural Network (NN) algorithm was developed to estimate global surface soil moisture for April 2015 to March 2017 with a 2-3 day repeat frequency using passive microwave observations from the Soil Moisture Active Passive (SMAP) satellite, surface soil temperatures from the NASA Goddard Earth Observing System Model version 5 (GEOS-5) land modeling system, and Moderate Resolution Imaging Spectroradiometer-based vegetation water content. The NN was trained on GEOS-5 soil moisture target data, making the NN estimates consistent with the GEOS-5 climatology, such that they may ultimately be assimilated into this model without further bias correction. Evaluated against in situ soil moisture measurements, the average unbiased root mean square error (ubRMSE), correlation and anomaly correlation of the NN retrievals were 0.037 m³m^-3, 0.70 and 0.66, respectively, against SMAP core validation site measurements and 0.026 m³m^-3, 0.58 and 0.48, respectively, against International Soil Moisture Network (ISMN) measurements. At the core validation sites, the NN retrievals have a significantly higher skill than the GEOS-5 model estimates and a slightly lower correlation skill than the SMAP Level-2 Passive (L2P) product. The feasibility of the NN method was reflected by a lower ubRMSE compared to the L2P retrievals as well as a higher skill when ancillary parameters in physically-based retrievals were uncertain. Against ISMN measurements, the skill of the two retrieval products was more comparable. A triple collocation analysis against Advanced Microwave Scanning Radiometer 2 (AMSR2) and Advanced Scatterometer (ASCAT) soil moisture retrievals showed that the NN and L2P retrieval errors have a similar spatial distribution, but the NN retrieval errors are generally lower in densely vegetated regions and transition zones.

Prothrombotic changes in hemostatic parameters and C-reactive protein in the elderly with winter acute respiratory tract infections

Mortality rates attributable to cerebrovascular and ischemic heart disease increase among older adults during the winter. Prothrombotic changes in the hemostatic system related to seasonal factors, such as ambient temperature changes, and winter acute respiratory tract infections, may contribute to this excess seasonal mortality. A prospective nested case-control study was conducted to assess the impact of winter acute respiratory tract infections on fibrinogen, factor VII, factor VIIa, D-dimer, prothrombin fragment 1.2, PAI-1, soluble P-selectin and C-reactive protein (CRP) in older adults. The change in laboratory parameters from baseline (fall) to the time of infection in both middle-aged and elderly individuals was compared with matched non-infected controls. In older adult participants with winter acute respiratory tract infections, significant increases occurred in fibrinogen and C-reactive protein, but not in any other markers. The mean fibrinogen increased 1.52 g/L (38%) and the mean CRP increased 37 mg/L (370%) over baseline (both p <0.001). In a multivariate analysis, both infection and season were associated with the increase in fibrinogen, but only infection was associated with the CRP increase. Old age magnified the increase in CRP but not in fibrinogen. Winter acute respiratory tract infections induce an exaggerated inflammatory response in older adults. The associated increase in fibrinogen, an independent risk factor for ischemic heart disease, may be partly responsible for the excess winter vascular mortality.

Hepatitis B immunization of healthy elderly adults: relationship between naïve CD4+ T cells and primary immune response and evaluation of GM-CSF as an adjuvant

The efficacy of granulocyte-macrophage colony-stimulating factor (GM-CSF) to enhance the primary immune response to hepatitis B vaccine was studied in healthy elderly with young volunteers included as controls in this double-blind, placebo-controlled trial of GM-CSF as an immune adjuvant. Naïve T-helper cells (CD4+CD45RA+) were determined at baseline. Forty-five healthy elderly (average age, 74 years) and 37 healthy young controls (average age, 28 years) were randomized. Hepatitis B vaccine was administered at 0, 1, and 6 months. GM-CSF as a single injection of either 80 microg or 250 microg with the first and second doses of hepatitis B vaccine. In this trial GM-CSF did not enhance antibody responses. However, the antibody responses were dramatically different between these two groups: 35/35 young developed a protective titer versus 19/45 elderly (P < 0.0001). In addition, the mean logarithm of anti-hepatitis B antibody level in the 35 young who completed the study was 3.17 (log mIU/ml) but only 2.21 in the 19 elderly responders (P < 0.0001). Naïve T-helper cells differed significantly between the two groups: the mean percentage of CD4+CD45RA+ T cells was 47.9% versus 35.0% (P < 0.0001) in the young and elderly volunteers respectively. Naïve T cells also differed significantly between elderly who did or did not respond to HBV (39.9% vs. 31.7%, P = 0.039). Using linear regression, age, and percent naive, CD4 T cells were determined to significantly influence the anti-hepatitis B antibody response, but sex and dose of GM-CSF did not. For a two-parameter model: logarithm of antibody titer = (-0.038 x age in years) + (0.031 x % naïve CD4T cells) + 2.68; adjusted r2 = 0.605 and P < 0.0001. However, age had a larger effect than naive CD4 T cells, i.e., in comparing young and elderly groups the log antibody titer decreased by 1.73 due to the increase in age but only 0.40 due to the decrease in naive CD4 T cells. Thus, there was a large effect of age that could not be explained by the quantitative change in the naïve T-helper cells.

Primary prevention of childhood lead exposure: A randomized trial of dust control

BACKGROUND

Dust control is recommended as one of the primary strategies to prevent or control children's exposure to residential lead hazards, but the effect of dust control on children's blood lead levels is poorly understood.

OBJECTIVE

To determine the effectiveness of dust control in preventing children's exposure to lead, as measured by blood lead levels, during their peak age of susceptibility.

DESIGN

A randomized, controlled trial.

SETTING

Rochester, NY.

PARTICIPANTS

A total of 275 urban children were randomized at 6 months of age, of whom 246 (90%) were available for the 24-month-old follow-up visit.

INTERVENTIONS

Children and their families were randomly assigned to an intervention group (n = 140), which received cleaning equipment and up to eight visits by a dust control advisor, or a control group (n = 135).

OUTCOME MEASURES

Geometric mean blood lead levels and prevalence of elevated blood lead levels (ie, >10 microg/dL, 15 microg/dL, and 20 microg/dL).

RESULTS

At baseline, children's geometric mean blood lead levels were 2.9 microg/dL (95% confidence interval [CI] = 2.7, 3.1); there were no significant differences in characteristics or lead exposure by group assignment, with the exception of water lead levels. For children in the intervention group, the mean number of visits by a dust control advisor during the 18-month study period was 6.2; 51 (36%) had 4 to 7 visits, and 69 (49%) had 8 visits. At 24 months of age, the geometric mean blood lead was 7.3 microg/dL (95% CI = 6.6, 8.2) for the intervention group and 7.8 microg/dL (95% CI = 6.9, 8. 7) for the control group. The percentage of children with a 24-month blood lead >/=10 microg/dL, >/=15 microg/dL, and >/=20 microg/dL was 31% versus 36%, 12% versus 14%, and 5% versus 7% in the intervention and control groups, respectively.

CONCLUSIONS

We conclude that dust control, as performed by families and in the absence of lead hazard controls to reduce ongoing contamination from lead-based paint, is not effective in the primary prevention of childhood lead exposure.

Role of cytomegalovirus in the T cell changes seen in elderly individuals

The effect of prior cytomegalovirus (CMV) infection on the immune system was evaluated in young and elderly volunteers. Prevalence of IgG antibodies to CMV was higher in the elderly volunteers. In both age groups, there was a strong association with CMV seropositivity and increased number of CD28- CD4 or CD8 T cells, as well as with increased numbers of T cells expressing CD56 or DR. Although these changes have previously been reported to be age-related, they were independent of age when CMV serological status was taken into account. In contrast, both age group and CMV status were important determinants of the total number of T cells, the number of CD8 T cells, and the number of CD8 T cells expressing CD45RA or CD28. These findings indicate that prior infection with CMV, as reflected by CMV serological status, has important effects on T cell subsets and surface markers and must be considered whenever evaluating age-related changes in immunological parameters.

Medical practice with nursing home residents: results from the National Physician Professional Activities Census

OBJECTIVE

The study describes the prevalence of medical nursing home practice. Further, it examines the extent to which physician characteristics and local county health care resources predict nursing home involvement. This information is relevant to evaluating and devising strategies that address the future provision of medical care in institutionalized long-term care.

DESIGN

A cross-sectional survey.

SETTING

A national sample of all licensed practicing physicians was obtained from a special Professional Activities (PPA) survey conducted by the American Medical Association (AMA) in 1991.

PARTICIPANTS

Respondents were 21,578 physicians involved in direct patient care.

MEASURES

The typical number of hours spent weekly caring for nursing home patients was obtained from the PPA survey, and physician demographics were obtained from the AMA Masterfile. County health care resources were obtained from the National Institutes of Health Area Resources File.

RESULTS

Most (77%) physicians reported spending no measurable time caring for nursing home patients. In all disciplines, a majority of physicians with a nursing home practice spent less than 2 hours per week with patients. Logistic regressions indicted that family practitioners and internists were most likely to have a nursing home practice, but general practitioners were most likely to spend more time in practice. Only 15% of specialists reported having a nursing home practice. Prevalence of practice was greatest among solo practitioners and physicians in partnerships and least among academic and hospital-based physicians and physicians in group practice or employed by the government. Most county of practice resources were not associated or were modestly associated with nursing home practice, but having a nursing home practice became much more likely as the number of nursing home residents increased and hospital beds decreased. A pattern was found for nursing home practice to be slightly less likely as the county's per capita income and the proportion of proprietary nursing facilities increased.

CONCLUSIONS

With increasing numbers of older and frailer residents, nursing homes will continue to be integral components of the future healthcare system. However, physicians currently spend minimal time caring for nursing home patients, with physician characteristics best predicting involvement. Questions remain about the future of nursing home medical practice and how to best recruit, staff, and train future cadres of physicians to provide sufficient quality care for nursing home patients in an evolving health care system.

Gene-environment interaction in vulnerability to schizophrenia: findings from the Finnish Adoptive Family Study of Schizophrenia

OBJECTIVE

This study assessed the interaction of genetic risk and rearing-family risk as a subsyndromal test measure of schizophrenic thought disorder in adoptees.

METHOD

A group of 58 adoptees with schizophrenic biological mothers was compared with 96 comparison adoptees at ordinary genetic risk; putative adoptee vulnerability was assessed blindly and reliably by using the Rorschach Index of Primitive Thought. Environmental risk was measured by using frequency of communication deviance as a continuous variable, scored independently from Rorschach assessments of the adoptive parents.

RESULTS

High genetic risk in itself was not associated with greater vulnerability to schizophrenic thought disorder in the adoptees, as indicated by the Index of Primitive Thought. Also, greater communication deviance in the adoptive parents was not associated with greater thought disorder in the comparison adoptees. However, there was a highly significant gene-environment interaction. Among the offspring of the adoptive parents with high levels of communication deviance, a higher proportion of high-risk than comparison adoptees showed evidence of thought disorder. In contrast, among the offspring of adoptive parents with low communication deviance, a lower proportion of high-risk than comparison adoptees showed evidence of thought disorder. The distribution of communication deviance scores did not differ significantly between the adoptive parents of high-risk offspring and the adoptive parents of comparison offspring.

CONCLUSIONS

The findings are consistent with genetic control of sensitivity to the environment. There is no evidence that high genetic risk of schizophrenia among offspring is associated with high levels of communication problems in rearing parents.

Carbamazepine treatment of agitation in nursing home patients with dementia: a preliminary study

OBJECTIVE

To determine the effects of carbamazepine versus placebo on ratings of behavior in agitated nursing home patients with dementia.

DESIGN

Nonrandomized, placebo-controlled, crossover trial conducted in 25 patients in two nursing homes.

INTERVENTION

Carbamazepine and placebo were administered during two 5-week periods separated by a 2-week washout. The carbamazepine dose was determined for each patient by a nonblinded physician who did not participate in ratings (modal dose 300 mg/day).

MEASUREMENTS

The primary outcome measures were Brief Psychiatric Rating Scale scores and Clinical Global Impression of Change, rated by blind observers. Secondary measures of behavior, adversity, cognition, and functional status were also included.

MAIN RESULTS

Median total Brief Psychiatric Rating Scale score decreased 7 points on carbamazepine versus 3 on placebo (P = 0.03). Sixteen subjects were rated as improved globally on carbamazepine versus four on placebo (P = 0.001). Secondary measures of behavior showed similar changes at significant or suggestive (P < 0.10) levels. One subject developed carbamazepine-induced tics, and one died with a pneumonia. There was minimal other adversity.

CONCLUSION

This preliminary study suggests that carbamazepine in low doses can reduce agitated behaviors in some patients, with limited adversity resulting. Further research is required to confirm and extend this finding before it can be considered routine clinical practice.