A modified production function analysis of changing southern forest productivity

1991 ◽  
Vol 21 (8) ◽  
pp. 1278-1287 ◽  
Author(s):  
David H. Newman
Keyword(s):  
Production Function ◽  
Function Analysis ◽  
Public Lands ◽  
Forest Productivity ◽  
Southern States ◽  
The Past ◽  
Lower Productivity ◽  
Aggregate Production Function ◽  
The Impact ◽  
Productivity Gains

The analysis in this paper measures changes in forest productivity for 12 southern states using a modified, aggregate production function. The function combines cross section – time series, biological, and acreage data to estimate the shift in productivity, measured as either standing inventory plus removals or changes in inventory plus removals, over the past 4 decades. The annual shift in productivity is estimated to be approximately 0.5% for the standing volume measures used. However, productivity gains in the region have virtually stopped during the past decade. The largest contributions to productivity gains were from industrially owned lands and land managed as planted pine. Mixed pine–hardwood stands and public lands (except for plantations) showed lower productivity impacts. These results present an essential component for understanding the impact of technical change on aggregate forest productivity in the southern United States.

scholarly journals BIASED TECHNICAL CHANGE, INTERMEDIATE GOODS, AND TOTAL FACTOR PRODUCTIVITY

2011 ◽  
Vol 16 (2) ◽  
pp. 184-203 ◽  
Author(s):  
Alessio Moro
Keyword(s):  
Total Factor Productivity ◽  
Production Function ◽  
Technical Change ◽  
Value Added ◽  
Intermediate Goods ◽  
Factor Productivity ◽  
Aggregate Production ◽  
Tfp Growth ◽  
Aggregate Production Function ◽  
The Impact

In this paper I show that the intensity at which intermediate goods are used in the production process affects aggregate total factor productivity (TFP). To do this, I construct an input–output model economy in which firms produce gross output by means of a production function in capital, labor, and intermediate goods. This production function is subject, together with the standard neutral technical change, to intermediates-biased technical change. Positive (negative) intermediates-biased technical change implies a decline (increase) in the elasticity of gross output with respect to intermediate goods. In equilibrium, this elasticity appears as an explicit part of TFP in the value added aggregate production function. In particular, when the elasticity of gross output with respect to intermediates increases, aggregate TFP declines. I use the model to quantify the impact of intermediates-biased technical change for measured TFP growth in Italy. The exercise shows that intermediates-biased technical change can account for the productivity slowdown observed in Italy from 1994 to 2004.

scholarly journals Arterivirus molecular biology and pathogenesis

2013 ◽  
Vol 94 (10) ◽  
pp. 2141-2163 ◽  
Author(s):  
Eric J. Snijder ◽  
Marjolein Kikkert ◽  
Ying Fang
Keyword(s):  
Reverse Genetics ◽  
Function Analysis ◽  
Evolutionary Relationship ◽  
Disease Outbreaks ◽  
Equine Arteritis Virus ◽  
Respiratory Syndrome Virus ◽  
The Past ◽  
Protein Functions ◽  
The Usa ◽  
The Impact

Arteriviruses are positive-stranded RNA viruses that infect mammals. They can cause persistent or asymptomatic infections, but also acute disease associated with a respiratory syndrome, abortion or lethal haemorrhagic fever. During the past two decades, porcine reproductive and respiratory syndrome virus (PRRSV) and, to a lesser extent, equine arteritis virus (EAV) have attracted attention as veterinary pathogens with significant economic impact. Particularly noteworthy were the ‘porcine high fever disease’ outbreaks in South-East Asia and the emergence of new virulent PRRSV strains in the USA. Recently, the family was expanded with several previously unknown arteriviruses isolated from different African monkey species. At the molecular level, arteriviruses share an intriguing but distant evolutionary relationship with coronaviruses and other members of the order Nidovirales. Nevertheless, several of their characteristics are unique, including virion composition and structure, and the conservation of only a subset of the replicase domains encountered in nidoviruses with larger genomes. During the past 15 years, the advent of reverse genetics systems for EAV and PRRSV has changed and accelerated the structure–function analysis of arterivirus RNA and protein sequences. These systems now also facilitate studies into host immune responses and arterivirus immune evasion and pathogenesis. In this review, we have summarized recent advances in the areas of arterivirus genome expression, RNA and protein functions, virion architecture, virus–host interactions, immunity, and pathogenesis. We have also briefly reviewed the impact of these advances on disease management, the engineering of novel candidate live vaccines and the diagnosis of arterivirus infection.

scholarly journals III Health and agricultural production: Evidence from Kogi State of Nigeria

2014 ◽  
Vol 14 (61) ◽  
pp. 8488-8503
Author(s):  
U Onuche ◽  
◽  
HI Opaluwa ◽  
MH Edoka
Keyword(s):  
Production Function ◽  
Rural Areas ◽  
Agricultural Production ◽  
Formal Education ◽  
Function Analysis ◽  
Farm Size ◽  
Development Effort ◽  
Farm Work ◽  
Household Heads ◽  
The Impact

This study was carried out to analyse the impact of ill health on agricultural outputs in rural areas of Kogi state, central Nigeria. The motivation derives from the fact that rural areas which are strategically important for national food security are more prone to health hazards as a result of the poor nature of health services arising partly from neglect by government. The objectives were to present the socioeconomic characteristics of the rural farm households and identify the prevailing health and agricultural production nexus in the area. The use of multistage random sampling procedure was employed in the selection of 263 rural households for questionnaire administration in order to elicit relevant data related to their farming enterprises and health. The use of descriptive statistics and production function analysis were employed. The study revealed that the average age of the household heads was 46.4 years while the average household size was 6.5 persons. Also, the average farm size was 1.43 ha and the average number of years of formal education was found to be 7.4. Furthermore, the study revealed that the most prominent disease conditions affecting farm families were malaria fever, typhoid fever and diarrhea and these led to an average of 8.2 days reduction in time available for farm work in a farming season. Result from the production function analysis revealed that the elasticities of farm size (0.419), family size (0.099), number of contacts with extension staff (0.018), labour (0.012) and naira amount of credit accessed (0.25) were positively signed and significant at 1%, 10%, 1%, 5% and 1% respectively; while number of days of farm work lost to ill health was negatively signed (-0.09) and significant at 5%. Findings suggest that focusing on number of days of farming activities lost to ill health in a household might help elicit a clearer picture of the effect of transient ill health on agricultural production. More research and development effort in the provision of and accessibility to health care in the rural areas in order to reduce the incidence of diseases are recommended. Such efforts should also include the provision of adequate health and environmental education for the rural population as the most common ailments discovered in the study area are actually hygiene and environment related.

Farm Tractorization, Fertilizer Use and Productivity of Mexican Wheat in Pakistan

1981 ◽  
Vol 20 (3) ◽  
pp. 323-345 ◽  
Author(s):  
Abdul Salam
Keyword(s):  
Comparative Analysis ◽  
Survey Data ◽  
Production Function ◽  
Significant Contribution ◽  
Function Analysis ◽  
Wheat Crop ◽  
Chemical Fertilizers ◽  
Yield Data ◽  
Fertilizer Use ◽  
The Impact

Using survey data the impact of tractorization on wheat productivity is examined in this paper. A comparative analysis of yield data indicates that wheat yields on tractor farms are significantly higher than those on bullock farms. It is also found that tractor farms use higher amounts of chemical fertilizers on their wheat crop. The results of production function analysis also confirm the significant contribution of tractorization in achieving higher wheat yields.

The Implications of the Adoption of Alternative Production Practices on the Estimation of Input Productivity in Agriculture

1997 ◽  
Vol 8 (2) ◽  
pp. 133-150
Author(s):  
C.S. Kim ◽  
C. Sandretto ◽  
N.D. Uri
Keyword(s):  
Human Health ◽  
Production Function ◽  
Consumptive Use ◽  
Production Practice ◽  
Production Function Approach ◽  
Level Of Use ◽  
Aggregate Production Function ◽  
Factor Inputs ◽  
The Impact ◽  
Fertilizer Demand

This paper explores the implications of a misspecification of the production function on the use of factor inputs in the context of the adoption of an alternative production practice (a technological innovation) designed to mitigate the impact of agricultural production on human health and the environment. It is demonstrated that if the level of use of some inputs is considered rather than their consumptive use (i.e., the actual amount used by a plant), the productivity of the input is inaccurately measured. It is also demonstrated that an aggregate production function approach can lead to overestimation of the value of the marginal product of an input due to the frequently implicit assumptions that the output supply, output demand, and fertilizer demand are infinitely price elastic. The implications of the results are important for determining the optimal use of inputs such as fertilizer and pesticides which have known adverse impacts on the environment and human health.

Fluorescent potentiometric dyes for membrane-potential imaging

1994 ◽  
Vol 52 ◽  
pp. 166-167
Author(s):  
Leslie M. Loew
Keyword(s):  
Membrane Potential ◽  
Single Cells ◽  
Quantitative Imaging ◽  
Optical Recording ◽  
Biological Processes ◽  
Major Focus ◽  
The Past ◽  
Excitable Systems ◽  
Major Application ◽  
The Impact

A major application of potentiometric dyes has been the multisite optical recording of electrical activity in excitable systems. After being championed by L.B. Cohen and his colleagues for the past 20 years, the impact of this technology is rapidly being felt and is spreading to an increasing number of neuroscience laboratories. A second class of experiments involves using dyes to image membrane potential distributions in single cells by digital imaging microscopy - a major focus of this lab. These studies usually do not require the temporal resolution of multisite optical recording, being primarily focussed on slow cell biological processes, and therefore can achieve much higher spatial resolution. We have developed 2 methods for quantitative imaging of membrane potential. One method uses dual wavelength imaging of membrane-staining dyes and the other uses quantitative 3D imaging of a fluorescent lipophilic cation; the dyes used in each case were synthesized for this purpose in this laboratory.

Perceived Burden of Informal Caregivers of a Chronically Ill Older Family Member

GeroPsych ◽  
2011 ◽  
Vol 24 (3) ◽  
pp. 143-154 ◽  
Author(s):  
Elmar Gräßel ◽  
Raffaela Adabbo
Keyword(s):  
Family Member ◽  
Informal Caregiver ◽  
Chronically Ill ◽  
Stress Model ◽  
The Past ◽  
Perceived Burden ◽  
Hypothetical Construct ◽  
Care Situation ◽  
The Impact ◽  
Further Development

The burden of caregivers has been intensively researched for the past 30 years and has resulted in a multitude of individual findings. This review illustrates the significance of the hypothetical construct of perceived burden for the further development and design of the homecare situation. Following explanations regarding the term informal caregiver, we derive the construct burden from its conceptual association with the transactional stress model of Lazarus and Folkman. Once the extent and characteristics of burden have been set forth, we then present the impact of perceived burden as the care situation. The question of predictors of burden will lead into the last section from which implications can be derived for homecare and relief of caregivers.

Soziale Disziplinierung im flexiblen Kapitalismus

2004 ◽  
Vol 34 (136) ◽  
pp. 339-356
Author(s):  
Tobias Wölfle ◽  
Oliver Schöller
Keyword(s):  
Social Welfare ◽  
Second Step ◽  
Social Rights ◽  
Federal Law ◽  
Capitalist Development ◽  
The Core ◽  
The Past ◽  
The Impact ◽  
Municipal Level

Under the term “Hilfe zur Arbeit” (aid for work) the federal law of social welfare subsumes all kinds of labour disciplining instruments. First, the paper shows the historical connection of welfare and labour disciplining mechanisms in the context of different periods within capitalist development. In a second step, against the background of historical experiences, we will analyse the trends of “Hilfe zur Arbeit” during the past two decades. It will be shown that by the rise of unemployment, the impact of labour disciplining aspects of “Hilfe zur Arbeit” has increased both on the federal and on the municipal level. For this reason the leverage of the liberal paradigm would take place even in the core of social rights.

Regulatory and sustainability initiatives lead to improved polyaminopolyamide epichlorohydrin (PAE) wet-strength resins and paper products

TAPPI Journal ◽  
2018 ◽  
Vol 17 (09) ◽  
pp. 519-532 ◽  
Author(s):  
Mark Crisp ◽  
Richard Riehle
Keyword(s):  
Health And Safety ◽  
Cost Effective ◽  
Worker Safety ◽  
Regulatory Requirements ◽  
Wet Strength ◽  
The Past ◽  
Consumer Safety ◽  
Federal Institute ◽  
Sustainability Initiatives ◽  
The Impact

Polyaminopolyamide-epichlorohydrin (PAE) resins are the predominant commercial products used to manufacture wet-strengthened paper products for grades requiring wet-strength permanence. Since their development in the late 1950s, the first generation (G1) resins have proven to be one of the most cost-effective technologies available to provide wet strength to paper. Throughout the past three decades, regulatory directives and sustainability initiatives from various organizations have driven the development of cleaner and safer PAE resins and paper products. Early efforts in this area focused on improving worker safety and reducing the impact of PAE resins on the environment. These efforts led to the development of resins containing significantly reduced levels of 1,3-dichloro-2-propanol (1,3-DCP) and 3-monochloropropane-1,2-diol (3-MCPD), potentially carcinogenic byproducts formed during the manufacturing process of PAE resins. As the levels of these byproducts decreased, the environmental, health, and safety (EH&S) profile of PAE resins and paper products improved. Recent initiatives from major retailers are focusing on product ingredient transparency and quality, thus encouraging the development of safer product formulations while maintaining performance. PAE resin research over the past 20 years has been directed toward regulatory requirements to improve consumer safety and minimize exposure to potentially carcinogenic materials found in various paper products. One of the best known regulatory requirements is the recommendations of the German Federal Institute for Risk Assessment (BfR), which defines the levels of 1,3-DCP and 3-MCPD that can be extracted by water from various food contact grades of paper. These criteria led to the development of third generation (G3) products that contain very low levels of 1,3-DCP (typically <10 parts per million in the as-received/delivered resin). This paper outlines the PAE resin chemical contributors to adsorbable organic halogens and 3-MCPD in paper and provides recommendations for the use of each PAE resin product generation (G1, G1.5, G2, G2.5, and G3).

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