151 research outputs found
Farm size adjustments in Iowa and cost economies in crop production for farms of different sizes
The relation of cost economies to size of farm has been a subject of considerable speculation in Iowa. Farmers are interested in farms of different sizes because cost advantages or disadvantages have an important bearing on farm profits. Other segments of the population have also been interested in size and scale economies in farming. Many people put forth the hypothesis that modern farming methods give very great cost economies to the large acreage. The supposition is: Mechanization results in very low per-acre costs for large units and a danger exists that these cost advantages will give rise to large-scale units which cause the liquidation of family-farm units. Whether or not a threat of this nature actually exists depends on the costs associated with farms of different sizes.
Discussion of farm size has gone on with very little knowledge of the cost economies realized in different types of agriculture. Certain aspects of cost are, however, evident: (1) Cost economies are likely greatest in grain and crop farming systems; mechanization has been developed particularly around these enterprises. Important changes have taken place in production of livestock. fruit and vegetable crops. However, the adaptation of mechanization to these enterprises has not been great. (2) If foods and fibers are to be produced efficiently, and farm families are to have favorable incomes, the size of the farm must be great enough to attain some of the efficiencies inherent in mechanization. Farms that are too small will result in low income
Level and Change in Alcohol Consumption, Depression and Dysfunctional Attitudes among Females Treated for Alcohol Addiction
Aims: To examine whether individual changes in alcohol consumption among female alcoholics under treatment are predicted by level of and changes in depression and dysfunctional attitudes. Method: A total of 120 women who were treated for alcohol addiction at the Karolinska Hospital in Stockholm (Sweden) were assessed twice over a 2-year period using the Depression scale from the Symptom Checklist-90, the Alcohol Use Inventory and the Dysfunctional Attitude Scale (DAS). Latent growth curve analysis was used. Results: Decrease in alcohol consumption, depression and dysfunctional attitude variables were found at group level. The results also showed significant individual variation in change. Changes in alcohol consumption were predicted by baseline alcohol drinking, as well as by level and changes in depression. Stronger reduction in depression was related to higher level of depression at baseline, and with reduction in dysfunctional attitudes. Different DAS sub-scales resulted in different magnitude of the model relations. Good treatment compliance was related to lower baseline level in depression, but also with higher baseline level in dysfunctional attitudes, and predicted stronger reduction in alcohol consumption. Conclusion: This paper shows the importance of incorporating both individual level and change in depression as predictors of change in alcohol consumption among subjects treated for alcohol addiction. Also, dysfunctional attitudes are both indirectly and directly related to treatment outcome. By incorporating alcohol consumption, depression and dysfunctional attitudes as targets of intervention, treatment compliance and outcome may be enhanced
Low-temperature thermochronology of the Indus Basin in central Ladakh, northwest India: implications of MioceneâPliocene cooling in the India-Asia collision zone
The IndiaâAsia collision zone in Ladakh, northwest India, records a sequence of tectonoâthermal events in the interior of the Himalayan orogen following the intercontinental collision between India and Asia in early Cenozoic time. We present zircon fissionâtrack, and zircon and apatite (UâTh)/He thermochronometric data from the Indus Basin sedimentary rocks that are exposed along the strike of the collision zone in central Ladakh. These data reveal a postâdepositional MioceneâPliocene (~22â4 Ma) cooling signal along the IndiaâAsia collision zone in northwest India. Our ZFT cooling ages indicate that maximum basin temperatures exceeded 200 °C but stayed below 280â300 °C in the stratigraphically deeper marine and continental strata. Thermal modeling of zircon and apatite (UâTh)/He cooling ages suggests postâdepositional basin cooling initiated in Early Miocene time by ~22â20 Ma, occurred throughout the basin across zircon (UâTh)/He partial retention temperatures from ~20â10 Ma, and continued in the Pliocene time until at least ~4 Ma. We attribute the burial of the Indus Basin to sedimentation and movement along the regional Great Counter thrust. The ensuing MioceneâPliocene cooling resulted from erosion by the Indus River that transects the basin. An approximately coeval cooling signal is well documented east of the study area, along the collision zone in south Tibet. Our new data provide a regional framework upon which future studies can explore the possible interrelationships between tectonic, geodynamic and geomorphologic factors contributing to MioceneâPliocene cooling along the IndiaâAsia collision zone from NW India to south Tibet
P/2010A2 LINEAR - I: An impact in the Asteroid Main Belt
Comet P/2010A2 LINEAR is a good candidate for membership with the Main Belt
Comet family. It was observed with several telescopes (ESO NTT, La Silla;
Gemini North, Mauna Kea; UH 2.2m, Mauna Kea) from 14 Jan. until 19 Feb. 2010 in
order to characterize and monitor it and its very unusual dust tail, which
appears almost fully detached from the nucleus; the head of the tail includes
two narrow arcs forming a cross. The immediate surroundings of the nucleus were
found dust-free, which allowed an estimate of the nucleus radius of 80-90m. A
model of the thermal evolution indicates that such a small nucleus could not
maintain any ice content for more than a few million years on its current
orbit, ruling out ice sublimation dust ejection mechanism. Rotational spin-up
and electrostatic dust levitations were also rejected, leaving an impact with a
smaller body as the favoured hypothesis, and ruling out the cometary nature of
the object.
The impact is further supported by the analysis of the tail structure.
Finston-Probstein dynamical dust modelling indicates the tail was produced by a
single burst of dust emission. More advanced models, independently indicate
that this burst populated a hollow cone with a half-opening angle alpha~40degr
and with an ejection velocity v_max ~ 0.2m/s, where the small dust grains fill
the observed tail, while the arcs are foreshortened sections of the burst cone.
The dust grains in the tail are measured to have radii between a=1-20mm, with a
differential size distribution proportional to a^(-3.44 +/- 0.08). The dust
contained in the tail is estimated to at least 8x10^8kg, which would form a
sphere of 40m radius. Analysing these results in the framework of crater
physics, we conclude that a gravity-controlled crater would have grown up to
~100m radius, i.e. comparable to the size of the body. The non-disruption of
the body suggest this was an oblique impact.Comment: 15 pages, 11 figures, in pres
Economics of some soil conservation practices
In applying conservation and fertility improvement plans, farmers have a choice between alternative combinations of land use, fertilizer applications and erosion control practices. Within limits, they may choose between different rotations and different fertilizer applications combined with different erosion control practices and still farm the land in accordance with the soil capabilities.
While land use in accordance with soil capabilities and appropriate fertilization is basic to soil conservation, these measures need to be supplemented by supporting conservation practices such as contouring, sod waterways, mulching, drainage, flumes, etc., if soil is to be conserved and improved most efficiently.
Successful conservation farming (that system which will increase total farm production, build up soil fertility, control erosion and maximize earnings) cannot be tailor-made to fit all farms but involves consideration of each individual\u27s situation. The farmer (and those working with him) must analyze his problem to determine his costs and returns for the farm as a whole under alternative combinations of crops, fertilization and supporting conservation measures to determine which system will best fit his capital position and abilities and still do the conservation job
Self-development groups reduce medical school stress: a controlled intervention study
<p>Abstract</p> <p>Background</p> <p>High stress levels and mental health problems are common among medical students and there is a lack of studies on group interventions that aim to reduce such distress during medical school.</p> <p>Methods</p> <p>A full class of students (n = 129) participated in group sessions during their third year of medical school in Bergen, Norway. The subsequent third-year class (n = 152) acted as control group, in order to create a quasi-experimental design. Two types of group intervention sessions were offered to the first class. One option was self-development groups led by trained group psychotherapists. Alternatively, students could choose discussion groups that focused on themes of special relevance to doctors, led by experienced general practitioners. The intervention comprised of 12 weekly group sessions each lasting 90 minutes. Data were gathered before the intervention (T1), and three months post intervention (T2). Distress was measured using the Perceived Medical School Stress (PMSS) and Symptom Check List-5 (SCL-5) assessments.</p> <p>Results</p> <p>The intervention group showed a significant reduction in PMSS over the observation period. The subsequent year control group stayed on the same PMSS levels over the similar period. The intervention was a significant predictor of PMSS reduction in a multiple regression analysis adjusted for age and sex, β = -1.93 (-3.47 to -0.38), P = 0.02. When we analysed the effects of self-development and discussion groups with the control group as reference, self-development group was the only significant predictor of PMSS reduction, β = -2.18 (-4.03 to -0.33), P = 0.02. There was no interaction with gender in our analysis. This implicates no significant difference between men and women concerning the effect of the self-development group. There was no reduction in general mental distress (SCL-5) over this period.</p> <p>Conclusion</p> <p>A three-month follow-up showed that the intervention had a positive effect on perceived medical school stress among the students, and further analyses showed this was due to participation in self-development groups.</p
Climate-Ready Landscape Plants: Garden Roses Trialed at Reduced Irrigation Frequency in Utah, USA
Increased urban and suburban populations in the arid western United States have resulted in more water demand; however, water availability in the region has become limited because of inadequate precipitation. Recent droughts have led to restrictions on irrigating landscape plants. Garden rose (Rosa Ăhybrida) is commonly used as flowering plants in residential landscapes, but its drought tolerance has not been widely studied. The objective of this study was to determine the impact of reduced irrigation frequency on visual quality, plant growth, and physiology of five garden rose cultivars, including ChewPatout (Oso EasyÂŽ Urban LegendÂŽ), Meibenbino (Petite Knock OutÂŽ), MEIRIFTDAY (Oso EasyÂŽ Double Pink), Overedclimb (Cherry Frostâ˘), and Radbeauty (Sitting Prettyâ˘). Twenty-four plants of each rose cultivar were established in a trial plot at Utah Agricultural Experiment Station Greenville Research Farm (North Logan, UT, USA) in Summer 2021. Plants were randomly assigned to one of three deficit irrigation treatments for which irrigation frequencies were calculated using 80% reference evapotranspiration (ETO) (high), 50% ETO (medium), and 20% ETO (low). The total volumes of irrigation water applied to each plant were 345.6, 172.8, and 43.2 L for the high, medium, and low irrigation frequencies, respectively, during the deficit irrigation trial from 12 May to 30 Sep 2022. Root zones were wetted more frequently as irrigation frequency increased from low to high irrigation frequencies. Decreased irrigation frequency increased the number of visibly wilted and damaged leaves on all rose cultivars. However, only âMeibenbinoâ and âMEIRIFTDAYâ exhibited a reduction in overall appearance under decreased irrigation frequency. The relative growth indices of both âMeibenbinoâ and âMEIRIFTDAYâ decreased by 6%, whereas the dry weights of their leaves decreased by 37% and 36%, respectively, as irrigation decreased from high to low frequencies. Roses in this study appeared to decrease stomatal conductance up to 51% when irrigation decreased from high to low frequencies, or when air temperature increased. âMeibenbinoâ and âMEIRIFTDAYâ exhibited unacceptable overall appearance, growth reduction, and higher leafâair temperature differences, and they were less tolerant to reduced irrigation. Although the âRadbeautyâ maintained plant growth under the reduced irrigation frequency, the large leaf size led to a more visibly wilted appearance and the potential for heat stress, thus impairing visual quality. âChewPatoutâ and âOveredclimbâ were most tolerant to deficit irrigation at 20% ETO and maintained plant growth with acceptable visual quality and lower leaf temperatures when they received one irrigation during the growing season
Axis I and II disorders as long-term predictors of mental distress: a six-year prospective follow-up of substance-dependent patients
<p>Abstract</p> <p>Background</p> <p>A high prevalence of lifetime psychiatric disorders among help-seeking substance abusers has been clearly established. However, the long-term course of psychiatric disorders and mental distress among help-seeking substance abusers is still unclear. The aim of this research was to examine the course of mental distress using a six-year follow-up study of treatment-seeking substance-dependent patients, and to explore whether lifetime Axis I and II disorders measured at admission predict the level of mental distress at follow-up, when age, sex, and substance-use variables measured both at baseline and at follow-up are controlled for. </p> <p>Methods</p> <p>A consecutive sample of substance dependent in- and outpatients (n = 287) from two counties of Norway were assessed at baseline (T1) with the Composite International Diagnostic Interview (Axis I), Millon's Clinical Multiaxial Inventory (Axis II), and the Hopkins Symptom Checklist (HSCL-25 (mental distress)). At follow-up (T2), 48% (137/287 subjects, 29% women) were assessed with the HSCL-25, the Alcohol Use Disorders Identification Test, and the Drug Use Disorders Identification Test. </p> <p>Results</p> <p>The stability of mental distress is a main finding and the level of mental distress remained high after six years, but was significantly lower among abstainers at T2, especially among female abstainers. Both the number of and specific lifetime Axis I disorders (social anxiety disorder, generalized anxiety disorder, and somatization disorder), the number of and specific Axis II disorders (anxious and impulsive personality disorders), and the severity of substance-use disorder at the index admission were all independent predictors of a high level of mental distress at follow-up, even when we controlled for age, sex, and substance use at follow-up.</p> <p>Conclusion</p> <p>These results underscore the importance of diagnosing and treating both substance-use disorder and non-substance-use disorder Axis I and Axis II disorders in the same programme.</p
Fat1 deletion promotes hybrid EMT state, tumour stemness and metastasis
FAT1, which encodes a protocadherin, is one of the most frequently mutated genes in human cancers1â5. However, the role and the molecular mechanisms by which FAT1 mutations control tumour initiation and progression are poorly understood. Here, using mouse models of skin squamous cell carcinoma and lung tumours, we found that deletion of Fat1 accelerates tumour initiation and malignant progression and promotes a hybrid epithelial-to-mesenchymal transition (EMT) phenotype. We also found this hybrid EMT state in FAT1-mutated human squamous cell carcinomas. Skin squamous cell carcinomas in which Fat1 was deleted presented increased tumour stemness and spontaneous metastasis. We performed transcriptional and chromatin profiling combined with proteomic analyses and mechanistic studies, which revealed that loss of function of FAT1 activates a CAMK2âCD44âSRC axis that promotes YAP1 nuclear translocation and ZEB1 expression that stimulates the mesenchymal state. This loss of function also inactivates EZH2, promoting SOX2 expression, which sustains the epithelial state. Our comprehensive analysis identified drug resistance and vulnerabilities in FAT1-deficient tumours, which have important implications for cancer therapy. Our studies reveal that, in mouse and human squamous cell carcinoma, loss of function of FAT1 promotes tumour initiation, progression, invasiveness, stemness and metastasis through the induction of a hybrid EMT state
HER-2 status of circulating tumor cells in a metastatic breast cancer cohort: A comparative study on characterization techniques
Background
Personalized targeted treatment in metastatic breast cancer relies on accurate assessment
of molecular aberrations, e.g. overexpression of Human Epidermal growth factor Receptor
2 (HER-2). Molecular interrogation of circulating tumor cells (CTCs) can provide an attractive alternative for real-time biomarker assessment. However, implementation of CellSearch-based HER-2 analysis has been limited. Immunofluorescent (IF) image
interpretation is crucial, as different HER-2 categories have been described. Major questions in CTC research are how these IF categories reflect gene expression and amplification, and if we should consider âmediumâ HER-2 expressing CTCs for patient selection.
Methods
Tumor cells from spiked cell lines (n = 8) and CTCs (n = 116 samples) of 85 metastatic
breast cancer patients were enriched using CellSearch. Comparative analysis of HER-2
expression by IF imaging (ACCEPT, DEPArray, and visual scoring) with qRT-PCR and
HER-2/neu FISH was performed.
Results
Automated IF HER-2-profiling by DEPArray and ACCEPT delivered comparable results.
There was a 98% agreement between 17 trained observers (visual scoring) and ACCEPT
considering HER-2neg and HER-2high expressing CTCs. However, 89% of HER-2med
expressing CTCs by ACCEPT were scored negative by observers. HER-2high expressing
tumor cells demonstrated HER-2/neu gene amplification, whereas HER-2neg and HER-2med
expressing tumor cells and CTCs by ACCEPT were copy-number neutral. All patients with HER-2-positive archival tumors had �1 HER-2high expressing CTCs, while 80% of HER-2-
negative patients did not. High relative gene expression of HER-2 measured on enriched
CTC lysates correlated with having �1 HER-2high expressing CTCs.
Conclusion
Automated images analysis has enormous potential for clinical implementation. HER-2
characterization and clinical trial design should be focused on HER-2high expressing CTCs
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