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Social Entrepreneurship in Non-Profit and Profit Sectors : Theoretical and Empirical Perspectives
This volume examines the theoretical and empirical landscape of social entrepreneurship in both non-profit and profit sectors. It extends the traditional view of social entrepreneurship to include the environmental and institutional factors that affect the emergence of social entrepreneurship activities, such as formal laws, regulations, procedures and informal institutions. The editors aim to provide evidence and increased understanding of this growing phenomenon. Social Entrepreneurship is gaining recognition as a key element of economic and social development. It embraces a wide set of situations with a broad scope of activities in for-profit and non-profit organizations interested in social performance and/or in economically profitable performance, with an emphasis on achieving social aim. In the strict sense, social entrepreneurship corresponds to entrepreneurs whose main concern is to achieve social objectives rather than to obtain personal financial profits. However, there is still much to be learned about the dynamics and processes of social entrepreneurship. The current literature in the field has tended to focus on psychological experiences and personal characteristics, or on organizational perspectives such as resources, capabilities and leadership. This book intends to provide theoretical frameworks and empirical studies to this very new and broad field. Specifically, this book provides a collection of contemporary research in the following topics: How to create opportunity through social innovation How to detect entrepreneurial opportunity to meet social needs How to develop social entrepreneurship, while still seeking profits How to discover opportunities for different forms of social entrepreneurship Featuring contributions from around the world, this book is a valuable source for students, academics, researchers, policy makers, and professionals in the area of social entrepreneurship.
Book
Understanding silicate hydration from quantitative analyses of hydrating tricalcium silicates
Silicate hydration is prevalent in natural and technological processes, such as, mineral weathering, glass alteration, zeolite syntheses and cement hydration. Tricalcium silicate (Ca
3
SiO
5
), the main constituent of Portland cement, is amongst the most reactive silicates in water. Despite its widespread industrial use, the reaction of Ca
3
SiO
5
with water to form calcium-silicate-hydrates (C-S-H) still hosts many open questions. Here, we show that solid-state nuclear magnetic resonance measurements of
29
Si-enriched triclinic Ca
3
SiO
5
enable the quantitative monitoring of the hydration process in terms of transient local molecular composition, extent of silicate hydration and polymerization. This provides insights on the relative influence of surface hydroxylation and hydrate precipitation on the hydration rate. When the rate drops, the amount of hydroxylated Ca
3
SiO
5
decreases, thus demonstrating the partial passivation of the surface during the deceleration stage. Moreover, the relative quantities of monomers, dimers, pentamers and octamers in the C-S-H structure are measured.
Despite its importance to the cement industry, tricalcium silicate hydration, with its sequence of induction, acceleration and deceleration steps, still hosts many open questions. Here,
29
Si nuclear magnetic resonance provides new information on the silicate polymerization mechanism and its kinetics.
Journal Article
Mapping Important Shark and Ray Areas (ISRAs) in the Central and South American Pacific: Existing knowledge and data needs
Identifying critical habitats is key to the conservation and recovery of threatened species. A third of chondrichthyans (sharks, rays, and chimaeras) are threatened with extinction but robust biological and ecological information to delineate critical habitats for many species remains limited. Here, we investigated (1) research outputs and trends across the Central and South American Pacific region to determine whether sufficient information was available to identify critical habitats; (2) whether regional Important Shark and Ray Areas (ISRAs) were spatially representative; (3) what species and which ecological traits were most commonly used in the delineation of critical habitats; and (4) discuss how ISRAs can inform research priorities and area-based management in support of chondrichthyan conservation. Sixty-five ISRAs were identified for 97 of 190 chondrichthyan species occurring in the region (51%). Across key life-history processes, reproductive areas were most identified (n = 50). Of 821 published studies (2,160 entries), 31.48% (28% entries) primarily focused on fisheries and 48.51% included enough information to inform the ISRA process. Most (58.98%) of these studies originated from Mexico (n = 342, 744 entries) and Ecuador (n = 147, 276 entries). France and Honduras had the least regional research outputs relevant to apply the ISRA Criteria. Significant ecological data gaps were identified in oceanic (including areas beyond national jurisdiction), deepwater (>200 m), and along the southern part of the region (i.e., southern Chile). Deepwater species, chimaeras, and 21% of threatened species had knowledge gaps that did not allow the identification of ISRAs. If area-based management decisions in this region were based on ISRAs, and effectively implemented and enforced, diversity hotspots and at least 97 species could receive protection, including 79% of threatened species and 54% of those considered range-restricted. Increased monitoring and research efforts, with a corresponding increase in funding to fill existing gaps is key to support the identification of important habitats across this region.
Journal Article
Influence of Accelerating Admixtures on the Reactivity of Synthetic Aluminosilicate Glasses
This research aims at gaining a further understanding of the impact of accelerating admixtures on the reactivity of supplementary cementitious materials (SCMs), which are widely used as a clinker replacement in blended cements. This was done on synthetic glasses with controlled composition and structure that mimic two types of real SCMs (slag and calcium-rich fly ash). The effects of DEIPA, TIPA, NaSCN and Na2S2O3 on the glass dissolution, hydration kinetics and reaction products were investigated. The obtained results concluded that the pH of the NaOH solution and the composition of the synthetic glass play a key role on the effect of the admixtures. In 0.1 M NaOH (pH = 13.0), all the studied admixtures inhibited the dissolution of slag-like glasses while they enhanced the dissolution of Ca-rich fly ash-like glasses, being Na2S2O3 the admixture that led to the highest increase of the dissolution rate of the Ca-rich fly ash-type glasses. In 1 M NaOH solutions (pH = 13.8), only the alkali admixtures (NaSCN and Na2S2O3) enhanced the degree of reaction of both glasses. In slag-type glasses pastes mixed with 1 M NaOH, the addition of 2% Na2S2O3 induced the highest increase of their reactivity as inferred by the total heat release and the amount of bound water. This is related to the formation of a high amount of S(II)-AFm, in addition to C-A-S-H, that would increase the aluminium undersaturation of the pore solution and consequently the further dissolution of the glass.
Journal Article
Global assessment of manta and devil ray gill plate and meat trade: conservation implications and opportunities
Due to overexploitation in fisheries partly driven by international trade demand, mobulid rays are among the most threatened of elasmobranch families. We conducted a global assessment of the state of manta and devil ray trade employing expert elicitation through country-focused online surveys (
n
= 109) and interviews (
n
= 21), along with analysis of the FAO Total Production and CITES Trade Databases, and online trade and physical store surveys in China and Hong Kong SAR. Findings across 75 countries reveal significant mobulid landings in 43 countries. Globally, mobulid meat is consumed locally in at least 35 countries and exported from ten, with five major destination countries. Gill plates are extracted in 14 countries and exported from at least 14 across Asia and Africa, with five major destination countries in Asia. Meat and gill plate prices ranged between 0.24 – 10 and 4.8 – 1260 USD/kg respectively, depending on country and product form. Physical retailers of gill plates declined in Guangzhou and Hong Kong SAR in the past decade, while online retailers increased, but overall, the total number of retailers rose from 41 to 135 between 2011 and 2023. By linking country-specific mobulid management data to their roles in the meat and gill plate trade, price ranges, consumption patterns, and landing data, we ranked 75 countries from highest to lowest impact upon mobulid populations, identifying 14 as high-priority. Findings highlight the need for improved capacity-building in fisheries management and stronger enforcement aimed collectively at reversing the current unsustainable consumption and trade of mobulids.
Journal Article
Description of first nursery area for a pygmy devil ray species (Mobula munkiana) in the Gulf of California, Mexico
Munk’s pygmy devil rays (
Mobula munkiana
) are medium-size, zooplanktivorous filter feeding, elasmobranchs characterized by aggregative behavior, low fecundity and delayed reproduction. These traits make them susceptible to targeted and by-catch fisheries and are listed as Vulnerable on the IUCN Red List. Multiple studies have examined fisheries impacts, but nursery areas or foraging neonate and juvenile concentrations have not been examined. This study describes the first nursery area for
M. munkiana
at Espiritu Santo Archipelago, Mexico. We examined spatial use of a shallow bay during 22 consecutive months in relation to environmental patterns using traditional tagging (n = 95) and acoustic telemetry (n = 7). Neonates and juveniles comprised 84% of tagged individuals and their residency index was significantly greater inside than outside the bay; spending a maximum of 145 consecutive days within the bay. Observations of near-term pregnant females, mating behavior, and neonates indicate an April to June pupping period. Anecdotal photograph review indicated that the nursery area is used by neonates and juveniles across years. These findings confirm, for the first time, the existence of nursery areas for Munk’s pygmy devil rays and the potential importance of shallow bays during early life stages for the conservation of this species.
Journal Article
Research Priorities to Support Effective Manta and Devil Ray Conservation
Manta and devil rays are filter-feeding elasmobranchs that are found circumglobally in tropical and subtropical waters. Although relatively understudied for most of the 20th century, public awareness and scientific research on these species has increased dramatically in recent years. Much of this attention has been in response to targeted fisheries, international trade in mobulid products, and a growing concern over the fate of exploited populations. Despite progress in mobulid research, major knowledge gaps still exist, hindering the development of effective management and conservation strategies. We assembled 30 leaders and emerging experts in the fields of mobulid biology, ecology and conservation to identify pressing knowledge gaps that must be filled to facilitate improved science-based management of these vulnerable species. We highlight focal research topics in the subject areas of taxonomy and diversity, life history, reproduction and nursery areas, population trends, bycatch and fisheries, spatial dynamics and movements, foraging and diving, pollution and contaminants, and sub-lethal impacts. Mobulid rays remain a poorly studied group, and therefore our list of important knowledge gaps is extensive. However, we hope that this identification of high priority knowledge gaps will stimulate and focus future mobulid research.
Journal Article
Reproductive behavior, seasonality, and distribution of three devil ray species (Mobula mobular, M. thurstoni, and M. munkiana) in the Southern Gulf of California, Mexico
We examined the reproductive behavior (courtship and mating), seasonality and its distribution in three Mobula species, spinetail, bentfin, and Munk’s devil rays (
M. mobular, M. thurstoni,
and
M. munkiana
) in the southwestern Gulf of California, Mexico, using boat surveys (with drone and in-water observations) (
n
= 69 survey days), spotter planes (
n
= 428 flights), and citizen science observations (
n
= 31). We examined whether (1) reproductive grounds existed within the area for any of these species, (2) whether reproductive behavior followed seasonal patterns, and (3) if this behavior was similar among all mobula rays. We observed reproductive behavior in 221 events in 2017 and 2021–2022, for
M. mobular
(
n
= 10),
M. thurstoni
(
n
= 3), and
M. munkiana
(
n
= 208) dispersed along 312 km of the eastern Baja California Peninsula between 4 m and 6.3 km away from the coast. Most events (
n
= 209) occurred in the La Ventana and Ensenada de Muertos areas. Courtship was observed for
M. mobular
and
M. thurstoni
and a copulation attempt for
M. munkiana
, with reproductive behavior following a seasonal pattern occurring from March to August, with a peak during May (81.9% of the events).
Mobula munkiana
displayed previously undescribed behaviors, such as the “piggyback leaps” as a pre-copulatory position and the “courtship vortex”, where 122 individuals were observed circling in a clockwise direction for 5 h with courtship groups joining and leaving the main vortex formation. This study highlights the areas of La Ventana and Ensenada de Muertos as critical habitats for reproductive behavior of two endangered and one vulnerable devil ray species.
Journal Article
Essential and non-essential trace element concentrations in muscle and liver of a pregnant Munk’s pygmy devil ray (Mobula munkiana) and its embryo
During gestation, essential and non-essential trace elements are transferred from the pregnant females to embryos. This study aimed to determine and compare the concentrations of seven essential trace elements (Fe, Zn, Se, Cu, Mn, Cr, Co) and six non-essential trace elements (As, Cd, V, U, Tl, Ag) in the muscle and the liver of a Munk’s pygmy devil ray pregnant female,
Mobula munkiana
, and its embryo. Transfer evidence of essential and non-essential trace elements was detected in
M. munkiana
tissues. Arsenic was found in elevated concentrations in the pregnant female and the embryo tissues. Elevated levels of Cd, V, U, and Ag were found in the pregnant female liver, but were minimal in the embryo tissue. This is the first study to investigate maternal transfer of essential and non-essential trace elements in these species and their reproductive strategy.
Journal Article
