MEASURING AND EXPLAINING THE DECLINE IN U.S. COTTON PRODUCTIVITY GROWTH

Tornquist input quantity indices were used to derive total and partial factor productivity measures for U.S. cotton across time, region, and scale. Total factor productivity for U.S. cotton increased .2 percent per year between 1974 and 1982. Partial productivity measures revealed that yield growth was about .6 percent and input use grew about .4 percent per year. Cotton enterprises in Alabama and Mississippi gained and those in the Texas High Plains lost competitive advantage relative to California. In 1982, very large (1750-5900 acres) and large (950-1749 acres) cotton enterprises were 2 percent more productive than medium-size enterprises (570-949 acres).Productivity Analysis,

ECONOMIES OF SIZE IN U.S. CROP PRODUCTION

Crop Production/Industries,

Neighbourhood socio-economic status and all-cause mortality in adults with atrial fibrillation: A cohort study of patients treated in primary care in Sweden.

Our aim was to study the potential impact of neighbourhood socio-economic status (SES) on all-cause mortality in patients with atrial fibrillation (AF) treated in primary care

Urolithiasis in immigrant groups:a nationwide cohort study in Sweden

Objective: To study the association between country of birth and incident urolithiasis in immigrant groups in Sweden, using individuals born in Sweden (or with Swedish-born parents in the second-generation study) as referents. Methods: This nationwide follow-up study included first- and second-generation immigrants residing in Sweden between 1 January 1998 and 31 December 2012. Urolithiasis was defined as having at least one registered diagnosis of urolithiasis in the National Patient Register. Cox regression analysis was used to estimate the risk (hazard ratios (HR) with 95% confidence intervals (CI)) of incident urolithiasis. The models were stratified by sex and adjusted for age, sociodemographic status and co-morbidity. Results: Compared to referents, slightly higher incidence rates and HRs of urolithiasis (HR; 95% CI) were observed among first-generation men (1.06; 1.04–1.09) and women (1.12; 1.08–1.16) but not among second-generation immigrants (persons born in Sweden with foreign-born parents). Among first-generation immigrants, higher HRs were noted among men and women from Central and Eastern Europe, Russia, Latin America, Africa and Asia. Lower HRs were seen among men and women from the Nordic countries, most Western European countries and North America. Among second-generation immigrants, higher HRs were noted among men and women from Denmark, Germany and Hungary, in men from Austria, and in women from the Netherlands and Poland. Lower HRs were seen in second generation immigrants from Latin America, Africa and Asia (men and women). Conclusions: We observed substantial differences in incidence of urolithiasis between certain immigrant groups and the Swedish-born population, of importance in the clinical situation

The association between sociodemographic characteristics and dementia in patients with atrial fibrillation

Objectives: Association between socio-demographic factors and dementia risk is studied in general but not for atrial fibrillation (AF) patients. Methods: We studied AF patients ≥ 45 years in Sweden 1998–2012 (n = 537,513) using the Total Population Register for socio-demographic factors, the Swedish Cause of Death Register, and the National Patient Register (NPR) for incident dementia. Cox regression with hazard ratios (HR) and 95% confidence intervals (CI) was used for the association between exposure and outcome, adjusting for age and comorbidities. Results: Totally 30,332 patients (5.6%) were diagnosed with dementia during the follow-up (mean 5.4 years). Of these, 14,097 were men (4.9%) and 16,235 were women (6.5%). Lower educational levels (reference: highest level) were associated with increased dementia, HRs (95% CI) for basic school for men 1.23 (1.18–1.29) and women 1.36 (1.30–1.42), and middle-level school for men 1.17 (1.11–1.22) and women 1.28 (1.22–1.34). Divorced men and women (reference: married) showed increased risk of dementia, HR 1.07 (1.01–1.13) and 1.12 (1.06–1.18), respectively, while widowed men showed lower risk, HR 0.84 (0.80–0.88). High deprivation neighborhood socio-economic status (NSES; reference: medium level) was associated with increased dementia in men, HR 1.11 (1.05–1.17), and low deprivation neighborhood socio-economic status (NSES) with increased dementia in men and women, HR 1.12 (1.06–1.18) and 1.18 (1.12–1.24), respectively. Conclusions: Some results were expected, i.e. association between lower educational level and dementia. The higher risk of dementia in low deprivation NSES-areas could be due to a higher awareness about dementia, and subsequent earlier diagnosis and treatment of dementia

Risk of Depression in Persons With alzheimer\u27s Disease: a National Cohort Study

INTRODUCTION: Depression is a risk factor and possible prodromal symptom of Alzheimer\u27s disease (AD), but little is known about subsequent risk of developing depression in persons with AD. METHODS: National matched cohort study was conducted of all 129,410 persons diagnosed with AD and 390,088 with all-cause dementia during 1998-2017 in Sweden, and 3,900,880 age- and sex-matched controls without dementia, who had no prior depression. Cox regression was used to compute hazard ratios (HRs) for major depression through 2018. RESULTS: Cumulative incidence of major depression was 13% in persons with AD and 3% in controls. Adjusting for sociodemographic factors and comorbidities, risk of major depression was greater than two-fold higher in women with AD (HR, 2.21; 95% confidence interval [CI], 2.11-2.32) or men with AD (2.68; 2.52-2.85), compared with controls. Similar results were found for all-cause dementia. DISCUSSION: Persons diagnosed with AD or related dementias need close follow-up for timely detection and treatment of depression. HIGHLIGHTS: In a large cohort, women and men with AD had \u3e2-fold subsequent risk of depression.Risks were highest in the first year (\u3e3-fold) but remained elevated ≥3 years later.Risk of depression was highest in persons aged ≥85 years at AD diagnosis.Persons with AD need close follow-up for detection and treatment of depression

Hypertension in Pregnancy among Immigrant and Swedish Women: a Cohort Study of all Pregnant Women in Sweden

BACKGROUND: Little is known about risks of hypertensive disorders of pregnancy in both first- and second-generation immigrant women in Europe and other Western countries; such knowledge may help elucidate the influence of genetic versus social factors on such risks. We aimed to study both first- and second-generation immigrant women for the presence of all types of hypertension (preexisting hypertension, gestational hypertension, preeclampsia, and eclampsia) during pregnancy. METHODS AND RESULTS: A cohort study was conducted using data derived from the Swedish National Birth Register, the National Patient Register, and the total Population Register. We used Cox regression analysis to compute hazard ratios (HRs) and 99% CIs while adjusting for sociodemographic factors and comorbidities. The first-generation study included a total of 1 084 212 deliveries and 68 311 hypertension cases, and the second-generation study included 989 986 deliveries and 67 505 hypertension cases. The fully adjusted HR (with 99% CI) for hypertension in pregnancy among first-generation immigrant women was 0.69 (0.66-0.72), and among second-generation immigrant women, it was 0.88 (0.86-0.91), compared with Swedish-born women with 2 Swedish-born parents. Women born in Finland or with parent(s) from Finland had higher risks, with fully adjusted HRs (99% CIs) of 1.30 (1.18-1.43) and 1.12 (1.07-1.17), respectively. CONCLUSIONS: Both first- and second-generation immigrant women had overall lower risks of hypertension in pregnancy compared with other Swedish women. However, the risk reduction was less pronounced in second-generation compared with first-generation immigrant women, suggesting that environmental factors in Sweden may have an important influence on risk of hypertension during pregnancy

Epilepsy in second-generation immigrants:a cohort study of all children up to 18 years of age in Sweden

Background and purpose: Our purpose was to study the association between country of birth and incident epilepsy in second-generation immigrants in Sweden. Methods: The study population included all children (n = 4 023 149) aged up to 18 years in Sweden. Epilepsy was defined as at least one registered diagnosis of epilepsy in the National Patient Register. The incidence of epilepsy, using individuals with Swedish-born parents as referents, was assessed by Cox regression, expressed in hazard ratios (HRs) and 95% confidence interval (95% CI). All models were stratified by sex and adjusted for age, geographical residence in Sweden, educational level, marital status, neighbourhood socioeconomic status and comorbid conditions, also using data from the Total Population Register. Results: A total of 26 310 individuals had a registered epilepsy event, i.e. 6.5/1000 (6.6/1000 amongst boys and 6.3/1000 amongst girls). After adjustment, the risk of epilepsy was lower than in children of Swedish-born parents. Amongst girls the significant HR was 0.85 (95% CI 0.81–0.88), but in boys only when adjusting also for comorbidity (HR 0.96, 95% CI 0.92–0.99). Amongst specific immigrant groups, a higher incidence of epilepsy was observed amongst boys with parents from Turkey and Africa, but not when adjusting for comorbidity, and a lower risk was observed in many other groups (boys with parents from Latvia, girls with parents from Finland, Iceland, Southern Europe, countries from the former Yugoslavia, and Asia). Conclusion: The risk of epilepsy was lower in second-generation immigrant children compared to children with Swedish-born parents, but with substantial differences between different immigrant groups

In vivo compartmentalization of functionally distinct, rapidly responsive antigen-specific T-cell populations in DNA-immunized or Salmonella enterica serovar Typhimurium-infected mice

The location and functional properties of antigen-specific memory T-cell populations in lymphoid and nonlymphoid compartments following DNA immunization or infection with Salmonella were investigated. Epitope-specific CD8+-T-cell expansion and retention during the memory phase were analyzed for DNA-immunized mice by use of a 5-h peptide restimulation assay. These data revealed that epitope-specific gamma interferon (IFN-{gamma})-positive CD8+ T cells occur at higher frequencies in the spleen, liver, and blood than in draining or peripheral lymph nodes during the expansion phase. Moreover, this distribution is maintained into long-term memory. The location and function of both CD4+ and CD8+ Salmonella-specific memory T cells in mice who were given a single dose of Salmonella enterica serovar Typhimurium was also quantitated by an ex vivo restimulation with bacterial lysate to detect the total Salmonella-specific memory pool. Mice immunized up to 6 months previously with S. enterica serovar Typhimurium had bacterium-specific CD4+ T cells that were capable of producing IFN-{gamma} or tumor necrosis factor alpha (TNF-{alpha}) at each site analyzed. Similar findings were observed for CD8+ T cells that were capable of producing IFN-{gamma}, while a much lower frequency and more restricted distribution were associated with TNF-{alpha}-producing CD8+ T cells. This study is the first to assess the frequencies, locations, and functions of both CD4+ and CD8+ memory T-cell populations in the same Salmonella-infected individuals and demonstrates the organ-specific functional compartmentalization of memory T cells after Salmonella infection