Productivity growth and product variety : gains from imitation and education

Is there a correlation between productivity and product variety? Certainly it appears that the rich countries are more productive and have more product variety than the poor nations. In fact, the relationship is quite strong when measured in levels. Does this same correlation hold up when measured in growth rates? If so, can poor countries imitate the success of the rich? Addison provides theoretical and empirical reasons to believe the answer to both questions is yes. Recent economic theory suggests that rising variety in factor inputs can help avoid diminishing marginal returns. Product variety can also sustain learning-by-doing which would otherwise be exhausted in a fixed number of products. Finally, invention or imitation adds to the stock of non-rival knowledge. There have been only two previous empirical tests of the correlation between growth in product variety and productivity growth. Both were affirmative but neither examined a wide range of developing countries and neither looked deeper to test what might drive product variety. This research is based on a cross-country sample of 29 countries (13 rich and 16 poor). The data display a statistically significant and positive relationship between growth in product variety and productivity growth when condition on other variables such as research and development (R&D) employment, macroeconomic stability, and domestic security. These results are robust to the addition and subtraction of various explanatory variables but fragile with respect to an influential data point for Venezuela. Industrial nations tend to generate most of their productivity gains through R&D employment in a stable environment that results in better production processes and product quality. In contrast, the largest source of productivity growth in developing countries is product variety imitation while instability takes away from productivity. Addison tests various explanations for growth in variety. The results show that nations furthest from the frontier of observable variety tend to imitate fastest, with the ability to imitate being improved by educational attainment and by productivity gains. This could be a source of hope for small, less developed nations. Growth in market size was not correlated with growth in variety, though this may be due to a rather short sample period of only eight years. In addition to the empirical testing, Addison also contributes to a general discussion of measurement concepts and measurement issues related to product variety and sets out an agenda for further research.Economic Theory&Research,Economic Conditions and Volatility,Environmental Economics&Policies,Public Health Promotion,Health Monitoring&Evaluation,Economic Theory&Research,Achieving Shared Growth,Environmental Economics&Policies,Inequality,Economic Growth

Synchronization Limits of Chaotic Circuits

Through system modeling with electronic circuits, two circuits were constructed that exhibit chaos over a wide ranges of initial conditions. The two circuits were one that modeled an algebraically simple “jerk” function and a resistor-inductor-diode (RLD) circuit where the diode was reverse-biased on the positive voltage cycle of the alternating current source. Using simulation data from other experiments, the waveforms, bifurcation plots, and phase space plots of the concrete circuit were verified. Identical circuits were then built containing variable components and coupled to their original, matching circuits. The variable components were used to observe a wide range of conditions to establish the desynchronization parameters and the range of synchronization

By How Much Does Conflict Reduce Financial Development?

Financial development is vulnerable to social conflict. Conflict reduces the demand for domestic currency as a medium of exchange and a store of value. Conflict also leads to poor quality governance, including weak regulation of the financial system, thereby undermining the sustainability of financial institutions. Conflict therefore reduces the social return to financial liberalization and other financial-sector reforms. This paper presents a theoretical model integrating the effects of conflict and financial liberalization, and then tests the model on data for 79 countries. Using an explanatory variable that measures the intensity of conflict (from low to high) the results show that conflict significantly reduces financial development, and that this negative effect increases as conflict intensifies. The paper concludes that conflict reduction is essential if financial reform is to have its full benefit for development

A neural network version of the measure correlate predict algorithm for estimating wind energy yield.

A neural network version of the measure correlate predict algorithm for estimating wind energy yiel

Optimizing in vitro extracellular matrix production using polymer scaffolds with targeted pore size

Extracellular matrix (ECM) has been shown to provide the framework needed for healthy tissue to grow after experiencing an injury. The optimization of growing ECM is a pressing concern in the tissue regeneration field. From prior research, an in vitro approach for harvesting ECM has been created using polyurethane (PU) foams seeded with cells. Our approach aimed at discovering if the pore size of the foams increased the amount of recovered ECM. Scaffolds of targeted pore size were created by separating sugar granules using a sieve, packing the sugar into a cylindrical mold, then pouring PU over the sugar. Three groups were created: a control of all sugar granules, sugar granules sized 250-500um, and sugar granules sized 125-250um. Cells were seeded and grown for three weeks on the foams. After three weeks, the scaffolds were dissolved and the ECM was collected. The final yields of each scaffold type produced statistically insufficient results. The control scaffolds yielded 4.15 mg ECM , the 125-250um pore scaffold yielded 3.55mg, and the 250-500um pore scaffold yielded 3.82mg. Further, the overall structures of the ECM did not appear different for each group. The results of the study show the pore size of the scaffold does not effect the overall production of ECM. Sieving sugar for specific pore size appears to have a minimal effect and is not necessary in creating the scaffolds

Healing Justice Spaces: Virtual Intersections of Religion, Environmentalism, and Social Justice

Healing justice (HJ) is a term and movement created by queer and trans people of color which combats the burnout and ableism in social justice work. It was created in response to the lack of access to quality healing services and health care for oppressed peoples and centers the decolonial modalities of healing used by oppressed communities. Healing justice holistically intervenes on intergenerational trauma and violence by providing individual and collective care, pushing back against the co-opting and capitalizing of Black and Indigenous healing practices to exclude the communities they were originally created to serve. I conducted virtual ethnographic research with a Los Angeles-based grassroots organization at the center of this movement, called Dignity & Power Now. Community members in the organization participate in digital healing justice spaces which were created due to the inability to gather in person. Work within these spaces facilitates connection to nature, spirituality, and activism in the non-digital lives of the individuals who participate. Work within these spaces allows individuals to claim their stories, develop sovereignty over the bodies, and empower their communities

Effects of Creatine Supplementation and Doxorubicin Treatment of Myostatin and Muscle Ring-Finger Protein-1 Expression in the Rat Diaphragm

Doxorubicin (DOX) is a highly potent chemotherapy drug that impacts the entire body rather than a targeted treatment area. While DOX treatment assists in the disruption and prevention of certain types of cancer growth, it damages many physiological processes in the body that were functioning normally and otherwise healthy prior to its administration. Damage induced by DOX on organ functioning can lead to other malignancies in the body, such as cachexia, cardiotoxicity, and myotoxicity, among others. Skeletal muscle relies on myogenic regulatory factors (MRFs), transcription factors expressed by satellite cells, for positive regulation of phases of muscle development and response to damage. In skeletal muscle, DOX administration has caused decreased MRF levels as well as increased myostatin and ubiquitin ligase expression, which are negative regulators of muscle mass. Previous findings have reported altered regulatory protein expression and shifts in muscle fiber characteristics of the diaphragm (DIA), as well as decline in patient respiratory function, following DOX treatment. Creatine monohydrate (Cr) supplementation prior to DOX administration has protected skeletal muscle against DOX-induced dysfunction, damage, and decline in MRF expression. However, the effects of DOX treatment in combination with Cr supplementation on the expression of proteins that negatively regulate muscle mass, such as myostatin and MuRF-1, in the DIA have yet to be investigated. PURPOSE: To investigate the effects of in vivo DOX administration, following the completion of two Cr supplementation protocols, on the expression of negative regulators of skeletal muscle mass, myostatin and MuRF-1, in the DIA tissue of rats sacrificed one- and three-days post-injection (N=115). METHODS: Male Sprague-Dawley rats were fed a diet supplemented with a standard Cr dosage of 2% for four weeks (CrS), a Cr loading dosage of 4% for one week and 2% for three weeks (CrL), or a standard control (CON) diet for four weeks. Based on random assignment, animals received an intraperitoneal injection of DOX (15 mg/kg) or saline (SAL) of the same volume and underwent anesthesia one- or three-days post-injection. Following DIA removal, Western blotting was used to quantify the protein expression of myostatin and MuRF-1. RESULTS: In the DIA, there was no significant diet effect, drug effect, or interaction at the one-day timepoint relating to myostatin expression (p = 0.255, p = 0.412, p = 0.770, respectively). There was also no diet effect, drug effect, or interaction pertaining to myostatin expression in the DIA at the three-day timepoint. (p = 0.710, p = 0.935, p = 0.566, respectively). In the DIA, there was no significant diet effect, drug effect, or interaction at the one-day timepoint pertaining to the expression of MuRF-1 (p = 0.772, p = 0.248, p = 0.137, respectively). There also was no diet effect, drug effect, or interaction relating to MuRF-1 expression in the DIA at the three-day timepoint (p = 0.826, p = 0.931, p = 0.941, respectively). CONCLUSION: There were no significant diet effects, drug effects, or interactions at either timepoint among myostatin and MuRF 1 protein expression in the DIA as determined by two-way ANOVA (p \u3e 0.05). These findings suggest that mediators and mechanisms unrelated to myostatin and MuRF-1 protein expression may contribute to the decline in respiratory function commonly observed in individuals undergoing chemotherapy treatment

Navigating Political Disagreement in Social Work: An Analysis of Past Literature, Ethical Guidance, and Case Examples

Political advocacy is a core tenet of the National Association of Social Workers (NASW) Code of Ethics. As a profes-sion, social work has the responsibility to remain aware of trends that threaten the well- being of diverse populations. Th e historic connection between oppression and policy is undeniable, and the standards and principles in the Code of Ethics require social workers to intervene and be aware of political trends. However, at times, social workers’ political views may not refl ect the clients’ views. Navigating situations in which a client expresses political content with the social worker requires careful consideration and improvements in the available guidance. Prior literature addresses the political confl ict in Israel, Palestine, and Northern Ireland during times of extreme tension in those cultures. Yet, stark contrasts between the United States and those cultures exist, thus justifying the need for specifi c guidance for U.S. social workers. Currently, the state of society and social work in the United States requires social workers to dedicate increased attentiveness to these types of situations. As such, the connection between social work and political action is undeniable and worthy of further investigation. To do so, two relevant case examples from a licensed clinical social worker (LCSW) will be assessed in which guidance from the NASW Code of Ethics, existing approaches, and prior literature will be applied. Th e evaluation of these case examples is intended to inform the decisions of other U.S.- based social workers confronting political disagreement with clients in direct practice work