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1.
Proc Natl Acad Sci U S A ; 119(23): e2115880119, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35648827

RESUMO

We analyze the transition from innovative ideas to final marketed products. This transition occurs through two synergetic supply chains for innovation and products. Basic concepts are developed, tested, upscaled, and introduced to commercial use in the innovation supply chain. Then, the products are produced and delivered to the consumer through the product supply chain. We argue that product markets trace their birth to product innovations. These markets tend to start as noncompetitive, which rewards innovators. Credit access and risk determine the reliance on contracting and product diffusion over space and time. The innovation and product supply chains are encouraged and facilitated by public policies, such as support for research and education, intellectual property rights protection, low barriers to trade, science-based regulation, and well-functioning capital markets. We argue for multidisciplinary research incorporating knowledge from economics, business, and engineering to better understand the evolution of innovative companies and supply chains. This understanding will help the development of policies to address challenges of climate change and food security among others.


Assuntos
Recursos Naturais
2.
Org Biomol Chem ; 20(26): 5254-5258, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35734894

RESUMO

Nano-formulated, combinatory therapeutics that control the spatiotemporal aspects of drug release have potential to overcome many of the challenges faced in cancer therapy. Herein, we describe a peptide nanotube functionalized with two anticancer drugs, 5-fluoruracil (5-FU) and camptothecin (CPT). The nanotube was formed via peptide self-assembly, which positioned 5-FU on the surface at the aqueous interface; whereas, CPT was sequestered within the hydrophobic walls. Thus, two different release profiles were observed: rapid release of 5-FU, followed by slower, sustained production of CPT. This profile emerged from the rapid hydrolytic cleavage of 5-FU at the aqueous/nanotube interface, which produced a smaller nanotube comprised of the peptide fragment.


Assuntos
Antineoplásicos , Camptotecina , Antineoplásicos/química , Camptotecina/química , Dipeptídeos , Liberação Controlada de Fármacos , Fluoruracila
3.
Agric Econ ; 52(3): 459-475, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34230730

RESUMO

Coronavirus disease 2019 and related lockdown policies in 2020 shocked food industry firms' supply chains in developing regions. Firms "pivoted" to e-commerce to reach consumers and e-procurement to reach processors and farmers. "Delivery intermediaries" copivoted with food firms to help them deliver and procure. This was crucial to the ability of the food firms to pivot. The pandemic was a "crucible" that induced this set of fast-tracking innovations, accelerating the diffusion of e-commerce and delivery intermediaries, and enabling food industry firms to redesign, at least temporarily, and perhaps for the long term, their supply chains to be more resilient, and to weather the pandemic, supply consumers, and contribute to food security. We present a theoretical model to explain these firm strategies, and then apply the framework to classify firms' practical strategies. We focus on cases in Asia and Latin America. Enabling policy and infrastructural conditions allowed firms to pivot and copivot fluidly.

4.
Bioorg Med Chem ; 25(1): 153-165, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27825554

RESUMO

Bacterial chemical communication, through a process called quorum sensing (QS), plays a central role in infection in numerous bacterial pathogens. Quorum sensing in Pseudomonas aeruginosa employs a series of small molecule receptors including the master QS regulator, LasR. In this study we investigate a non-natural triaryl series of LasR ligands using a combination of structure activity relationship studies and computational modeling. These studies have enabled the identification of key structural requirements for ligand binding and have revealed a new strategy for inducing the therapeutically relevant antagonism of LasR.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/agonistas , Proteínas de Bactérias/antagonistas & inibidores , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Transativadores/agonistas , Transativadores/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Humanos , Ligantes , Simulação de Acoplamento Molecular , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/fisiologia , Relação Estrutura-Atividade , Transativadores/metabolismo
5.
Food Policy ; 67: 93-105, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28413249

RESUMO

Recent evidence shows that many Sub-Saharan African farmers use modern inputs, but there is limited information on how these inputs are financed. We use recent nationally representative data from four countries to explore input financing and the role of credit therein. A number of our results contradict "conventional wisdom" found in the literature. Our results consistently show that traditional credit use, formal or informal, is extremely low (across credit type, country, crop and farm size categories). Instead, farmers primarily finance modern input purchases with cash from nonfarm activities and crop sales. Tied output-labor arrangements (which have received little empirical treatment in the literature) appear to be the only form of credit relatively widely used for farming.

6.
Proc Natl Acad Sci U S A ; 109(31): 12332-7, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-21135250

RESUMO

A "supermarket revolution" has occurred in developing countries in the past 2 decades. We focus on three specific issues that reflect the impact of this revolution, particularly in Asia: continuity in transformation, innovation in transformation, and unique development strategies. First, the record shows that the rapid growth observed in the early 2000s in China, Indonesia, Malaysia, and Thailand has continued, and the "newcomers"--India and Vietnam--have grown even faster. Although foreign direct investment has been important, the roles of domestic conglomerates and even state investment have been significant and unique. Second, Asia's supermarket revolution has exhibited unique pathways of retail diffusion and procurement system change. There has been "precocious" penetration of rural towns by rural supermarkets and rural business hubs, emergence of penetration of fresh produce retail that took much longer to initiate in other regions, and emergence of Asian retail developing-country multinational chains. In procurement, a symbiosis between modern retail and the emerging and consolidating modern food processing and logistics sectors has arisen. Third, several approaches are being tried to link small farmers to supermarkets. Some are unique to Asia, for example assembling into a "hub" or "platform" or "park" the various companies and services that link farmers to modern markets. Other approaches relatively new to Asia are found elsewhere, especially in Latin America, including "bringing modern markets to farmers" by establishing collection centers and multipronged collection cum service provision arrangements, and forming market cooperatives and farmer companies to help small farmers access supermarkets.


Assuntos
Agricultura/economia , Agricultura/tendências , Modelos Econômicos , Planejamento Social , Sudeste Asiático , China , Manipulação de Alimentos/economia , Humanos
7.
Nat Food ; 4(4): 288-293, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37117541

RESUMO

The Russia-Ukraine conflict has prompted calls for resource diversification and wheat self-sufficiency programmes in import-dependent regions. Here we show that this approach would have minimal impact on poor Nigerians as wheat constitutes only 4% of their total food consumption and 8% of their starchy staple consumption. In contrast, millets, rice, cassava and tubers are ten times more important-highlighting the need for careful consideration of country-context consumption patterns in response to external food system shocks.


Assuntos
Triticum , Verduras , Humanos , Ucrânia , Federação Russa , Pobreza
8.
Hippocampus ; 22(1): 106-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20882540

RESUMO

Throughout the adult life of most mammals, new neurons are continuously generated in the dentate gyrus of the hippocampal formation. Recent work has documented specific cognitive deficits after elimination of adult hippocampal neurogenesis in rodents, suggesting that these neurons may contribute to information processing in hippocampal circuits. Young adult-born neurons exhibit enhanced excitability and have altered capacity for synaptic plasticity in hippocampal slice preparations in vitro. Still, little is known about the effect of adult-born granule cells on hippocampal activity in vivo. To assess the impact of these new neurons on neural circuits in the dentate, we recorded perforant-path evoked responses and spontaneous network activity from the dentate gyrus of urethane-anesthetized mice whose hippocampus had been focally X-irradiated to eliminate the population of young adult-born granule cells. After X-irradiation, perforant-path responses were reduced in magnitude. In contrast, there was a marked increase in the amplitude of spontaneous γ-frequency bursts in the dentate gyrus and hilus, as well as increased synchronization of dentate neuron firing to these bursts. A similar increase in gamma burst amplitude was also found in animals in which adult neurogenesis was eliminated using the GFAP:TK pharmacogenetic ablation technique. These data suggest that young neurons may inhibit or destabilize recurrent network activity in the dentate and hilus. This unexpected result yields a new perspective on how a modest number of young adult-generated granule cells may modulate activity in the larger population of mature granule cells, rather than acting solely as independent encoding units.


Assuntos
Giro Denteado/fisiologia , Rede Nervosa/fisiologia , Neurogênese/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Animais , Grânulos Citoplasmáticos/fisiologia , Grânulos Citoplasmáticos/efeitos da radiação , Giro Denteado/citologia , Giro Denteado/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Rede Nervosa/citologia , Rede Nervosa/efeitos da radiação , Vias Neurais/citologia , Vias Neurais/fisiologia , Vias Neurais/efeitos da radiação , Neurogênese/efeitos da radiação , Plasticidade Neuronal/efeitos da radiação , Neurônios/citologia , Neurônios/efeitos da radiação
9.
Nanoscale ; 14(39): 14711-14716, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36169284

RESUMO

The spatiotemporal regulation of chemical reactivity in biological systems permits a network of metabolic reactions to take place within the same cellular environment. The exquisite control of reactivity is often mediated by out-of-equilibrium structures that remain functional only as long as fuel is present to maintain the higher energy, active state. An important goal in supramolecular chemistry aims to develop functional, energy dissipating systems that approach the sophistication of biological machinery. The challenge is to create strategies that couple the energy consumption needed to promote a molecule to a higher energy, assembled state to a functional property such as catalytic activity. In this work, we demonstrated that the assembly of a spiropyran (SP) dipeptide (1) transiently promoted the proline-catalyzed aldol reaction in water when visible light was present as fuel. The transient catalytic activity emerged from 1 under light illumination due to the photoisomerization of the monomeric, O-protonated (1-MCH+) merocyanine form to the spiropyran (1-SP) state, which rapidly assembled into nanosheets capable of catalyzing the aldol reaction in water. When the light source was removed, thermal isomerization to the more stable MCH+ form caused the nanosheets to dissociate into a catalytically inactive, monomeric state. Under these conditions, the aldol reaction could be repeatedly activated and deactivated by switching the light source on and off.


Assuntos
Dipeptídeos , Prolina , Aldeídos , Benzopiranos , Catálise , Dipeptídeos/química , Indóis , Nitrocompostos , Prolina/química , Água/química
10.
Science ; 377(6608): 810-813, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35981021

RESUMO

Implications for nutrition, environment, and work may be considerable.


Assuntos
Serviços de Alimentação , Política Nutricional
11.
Glob Food Sec ; 33: 100633, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35371913

RESUMO

African governments imposed mobility restrictions to suppress the spread of COVID-19. Many observers feared these measures would dramatically decrease incomes and increase food insecurity and anticipated that urban households would be much more impacted than rural ones. We use rural and urban survey data from 4000 households across five African countries to assess the pandemic's effect on incomes and food consumption. We find that a large share of the population saw incomes drop between March and July 2020. But these decreases were 43-63% smaller than predictions and early estimates, and highly correlated with the severity of restrictions. The income and food consumption impacts of the COVID-19 shock were widespread over both rural and urban areas. Policy making during a pandemic should recognize that restrictive measures will affect rural and urban, farming and non-farming, and richer and poorer households.

12.
Neuron ; 110(14): 2258-2267.e11, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35397211

RESUMO

The amygdala and prelimbic cortex (PL) communicate during fear discrimination retrieval, but how they coordinate discrimination of a non-threatening stimulus is unknown. Here, we show that somatostatin (SOM) interneurons in the basolateral amygdala (BLA) become active specifically during learned non-threatening cues and desynchronize cell firing by blocking phase reset of theta oscillations during the safe cue. Furthermore, we show that SOM activation and desynchronization of the BLA is PL-dependent and promotes discrimination of non-threat. Thus, fear discrimination engages PL-dependent coordination of BLA SOM responses to non-threatening stimuli.


Assuntos
Tonsila do Cerebelo , Complexo Nuclear Basolateral da Amígdala , Tonsila do Cerebelo/fisiologia , Complexo Nuclear Basolateral da Amígdala/fisiologia , Medo/fisiologia , Interneurônios/metabolismo , Córtex Pré-Frontal/fisiologia , Somatostatina/metabolismo
13.
Food Secur ; 13(6): 1577-1594, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659591

RESUMO

Small and medium enterprises (SMEs) in the midstream (processors, wholesalers and wholesale markets, and logistics) segments of transforming value chains have proliferated rapidly over the past several decades in Africa, Asia, and Latin America. Their spread has been most rapid in the long transitional stage between the traditional and modern stages, when value chains grow long and developed with urbanization but are still fragmented, before consolidation. Most of Sub-Saharan Africa and South Asia, and parts of the other regions, are in that stage. The midstream SMEs in output and input value chains are important to overall food security (moving about 65% of food consumed in Africa and South Asia), and to employment, farmers, poor consumers, and the environment. The midstream of value chains is neglected in the national and international debates as the "missing middle." We found that it is indeed not missing but rather hidden from the debate, hence "the hidden middle." The midstream SMEs grow quickly and succeed where enabling conditions are present. Our main policy recommendations are to support the SMEs further growth through a focus on infrastructure investment, in particular on wholesale markets and roads, a reduction of policy-related constraints such as excessive red tape, and regulation for food safety and good commercial practices.

14.
Chem Commun (Camb) ; 57(100): 13776-13779, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34860221

RESUMO

Light energy provides an attractive fuel source for energy dissipating systems because of the lack of waste production, wavelength tunability and the potential for spatial and temporal resolution. In this work, we describe a peptide-spiropyran conjugate that assembled into a transient nanofiber hydrogel in the presence of visible light, and dissociated when the light source was removed.


Assuntos
Hidrogéis/química , Peptídeos/química , Benzopiranos/química , Benzopiranos/efeitos da radiação , Hidrogéis/síntese química , Hidrogéis/efeitos da radiação , Luz , Nanofibras/química , Nanofibras/efeitos da radiação , Peptídeos/efeitos da radiação , Compostos de Espiro/química , Compostos de Espiro/efeitos da radiação
15.
Nat Food ; 2(10): 758-765, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37117971

RESUMO

Agrifood supply chains contribute to many environmental and social problems. Sustainability standards-rules that supply chain actors may follow to demonstrate their commitment to social equity and/or environmental protection-aim to mitigate such problems. We provide a narrative review of the effects of many distinct sustainability standards on different supply chain actors spanning multiple crops. Furthermore, we discuss five emerging questions-causality, exclusion, compliance and monitoring, excess supply and emerging country markets-and identify directions for future research. We find that, while sustainability standards can help improve the sustainability of production processes in certain situations, they are insufficient to ensure food system sustainability at scale, nor do they advance equity objectives in agrifood supply chains.

16.
Glob Food Sec ; 282021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33868911

RESUMO

African consumers have purchased increasing amounts of processed food over the past 50 years. The opportunity cost of time of women and men has increased as more of them work outside the home, driving them to buy processed food and food prepared away from home to save arduous home-processing and preparation labor. In the past several decades, this trend has accelerated with a surge on the supply side of the processing sector and small and medium enterprises (SMEs) and large private companies making massive aggregate investments. Packaged, industrialized, ultra-processed foods and sugar-sweetened beverages (SSBs) are a growing proportion of the processed food consumed. Also, in the past several decades, overweight and obesity have joined the long-standing high levels of stunting and wasting among children and extreme thinness among women of childbearing age. Together these phenomena have formed a double burden of malnutrition (DBM). The DBM has emerged as an important health problem in sub-Saharan Africa. The rise of the DBM and the increase in ultra-processed food consumption are linked. Policy makers face a dilemma. On the one hand, purchases of processed food are driven by long-term factors, such as urbanization, increased income, and employment changes, and thus policy cannot change the pursuit of convenience and labor-saving food. Moreover, much processed food, like packaged milk, is a boon to nutrition, and the processed food system is a major source of jobs for women. On the other hand, the portion (some 10-30%) of processed food that is ultra-processed is a public health challenge, and policy must address its detrimental effects on disease burden. The global experience suggests that double duty actions are most important as are selected policies focused on healthy weaning foods for addressing stunting and taxes on SSBs, nutrition labeling, and other measures can steer consumers away from unhealthy ultra-processed foods to addressing obesity and possibly child nutrition and stunting. We recommend that African governments consider these policy options, but note that the current extreme fragmentation of the processing sector, consisting of vast numbers of informal SMEs in sub-Saharan Africa, and the limited administrative/implementation capacity of many African governments require pursuing this path only gradually.

18.
J Allied Health ; 37(3): 156-61, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18847112

RESUMO

Attitudes and behaviors toward alcohol and other drug (AOD) use were assessed among a subgroup of allied health (AH) and physician assistant (PA) students within two university-based health professions educational institutions in a midwestern state in 1999. AH/PA student response was 423 (77.5%); this included occupational therapy (n = 81; 60.4%), physical therapy [PT] (n = 222; 98.7%), PA (n = 68; 85.0%), and other AH programs (n = 52; 48.1%). In this AH/PA group, a family history of alcohol-related problems was reported by 40.1% and drug-related problems by 11.3%, with 42.5% of respondents reporting one or both. Such histories of family alcohol and drug problems were reported by 47.8% or 18.5% of PA students, respectively. Past-year alcohol, tobacco, and marijuana use were reported, respectively, by 88.1%, 26.1%, and 6.7%. The highest percentage use of marijuana was reported by PT students (9.0%). Past-year blackouts were reported by 21.9%, driving after three or more drinks or any drug use by 49.3%, attendance at class or work under the influence of AOD by 7.8%, patient care under the influence of AOD by 3.3%, lowered grades or job evaluations from AOD use by 5.0%, and AOD-related legal charges by 4.5%. "Heavy drinking" (defined as consumption of five or more drinks per occasion during the past 2 weeks) was reported by 33.2%. Inadequate AOD education was reported by 55.1%, with 63.6% of PT respondents so reporting. AH and PA educational systems should proactively address student AOD prevention, education, and assistance needs.


Assuntos
Consumo de Bebidas Alcoólicas , Conhecimentos, Atitudes e Prática em Saúde , Estudantes de Ciências da Saúde/psicologia , Transtornos Relacionados ao Uso de Substâncias , Adulto , Feminino , Humanos , Masculino , Assunção de Riscos
20.
Am J Health Syst Pharm ; 63(21): 2116-22, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17057049

RESUMO

PURPOSE: The outcomes of pharmacist-managed diabetes care services in a community health center were studied. METHODS: Eligible patients were over age 18 years and had a diagnosis of type 2 diabetes mellitus. Patients were randomly assigned by the clinical pharmacist and nurse to the intervention group (n = 76) or control group (n = 73). Patients in the intervention group were enrolled in a pharmacist-managed diabetes care program. Patients in the control group received the standard diabetes care. The primary endpoint was reduction in glycosylated hemoglobin (HbA(1c)); secondary outcome measures included weight loss, an improved body mass index, decreased blood pressure, and an improved lipid panel. Quality-of-life measures (health level, satisfaction, impact, worry about disease, and worry about social and vocational issues) were also assessed. RESULTS: Demographic differences between groups were not remarkable. Mean HbA(1c) levels fell significantly (p < 0.05) from baseline to nine months in both groups. A difference of 1.0 was reported between the groups' HbA(1c) levels (95% confidence interval, 0.08-1.78; p < 0.05). Satisfaction level improved from 63.7 to 77.4 in the intervention group, which was significant when compared with the control group, whose satisfaction score improved from 57.0 to 63.4 (p < 0.05). CONCLUSION: Patients with type 2 diabetes mellitus who received pharmacist-managed diabetes care demonstrated improved HbA(1c), systolic blood pressure, and low-density-lipoprotein cholesterol levels and quality-of-life measures and met treatment goals more often than patients receiving standard care.


Assuntos
Centros Comunitários de Saúde , Diabetes Mellitus Tipo 2/tratamento farmacológico , Farmacêuticos , Adolescente , Adulto , Idoso , Feminino , Humanos , Iowa , Masculino , Pessoa de Meia-Idade , Papel Profissional , Resultado do Tratamento
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