scholarly journals Ontogenetic shift in the trophic role of the invasive killer shrimp Dikerogammarus villosus: a stable isotope study

2021 ◽  
Author(s):  
Francesco Mancini ◽  
Raffaele De Giorgi ◽  
Alessandro Ludovisi ◽  
Salvatrice Vizzini ◽  
Giorgio Mancinelli
Keyword(s):  
Dietary Habits ◽  
Trophic Position ◽  
Ecological Impact ◽  
Central Italy ◽  
Local Conditions ◽  
Dikerogammarus Villosus ◽  
Isotopic Signatures ◽  
Depth Analysis ◽  
Stable Isotope Study ◽  
The Impact

AbstractThe introduction of the amphipod Dikerogammarus villosus in European fresh waters is to date recognized as a threat to the integrity of invaded communities. Predation by D. villosus on native benthic invertebrates is assumed as the key determinant of its ecological impact, yet available information describe the species as a primary consumer as well as a carnivore depending on local conditions. Here, we assessed the trophic position (TP) of D. villosus in Lake Trasimeno, a recently invaded lentic system in central Italy, using the CN isotopic signatures of individuals captured in winter spanning two orders of magnitude in body size. TP estimations were compared with those characterizing the native amphipod Echinogammarus veneris and other representative invertebrate predators. On average, D. villosus showed a trophic position higher than E. veneris, and comparable with that of odonate nymphs. An in-depth analysis revealed that large-sized individuals had a trophic position of 3.07, higher than odonates and close to that of the hirudinean predator Erpobdella octoculata, while small-sized specimens had a trophic position of 2.57, similar to that of E. veneris (2.41). These findings indicate that size-related ontogenetic shifts in dietary habits may per se vary the nature of the interaction between Dikerogammarus villosus and native invertebrates from competition to predation. Information collated from published isotopic studies corroborated the generality of our results. We conclude that intra-specific trophic flexibility may potentially amplify and make more multifaceted the impact of the species on other invertebrate species in invaded food webs.

Black Markets and Militants

2021 ◽  
Author(s):  
Khalid Mustafa Medani
Keyword(s):  
Ethnic Politics ◽  
Economic Globalization ◽  
Economic Factors ◽  
Economic Networks ◽  
Local Conditions ◽  
Neoliberal Reforms ◽  
Depth Analysis ◽  
Original Contribution ◽  
The Impact ◽  
Socio Economic Factors

Understanding the political and socio-economic factors which give rise to youth recruitment into militant organizations is at the heart of grasping some of the most important issues that affect the contemporary Middle East and Africa. In this book, Khalid Mustafa Medani explains why youth are attracted to militant organizations, examining the specific role economic globalization, in the form of outmigration and expatriate remittance inflows, plays in determining how and why militant activists emerge. The study challenges existing accounts that rely primarily on ideology to explain militant recruitment. Based on extensive fieldwork, Medani offers an in-depth analysis of the impact of globalization, neoliberal reforms and informal economic networks as a conduit for the rise and evolution of moderate and militant Islamist movements and as an avenue central to the often, violent enterprise of state building and state formation. In an original contribution to the study of Islamist and ethnic politics more broadly, he thereby shows the importance of understanding when and under what conditions religious rather than other forms of identity become politically salient in the context of changes in local conditions.

scholarly journals The trophic position of the Atlantic blue crab Callinectes sapidus Rathbun 1896 in the food web of Parila Lagoon (South Eastern Adriatic, Croatia): a first assessment using stable isotopes.

2016 ◽  
Vol 17 (3) ◽  
pp. 634 ◽  
Author(s):  
G. MANCINELLI ◽  
B. GLAMUZINA ◽  
M. PETRIĆ ◽  
L. CARROZZO ◽  
L. GLAMUZINA ◽  
...  
Keyword(s):  
Blue Crab ◽  
Callinectes Sapidus ◽  
Trophic Position ◽  
Ecological Impact ◽  
River Estuary ◽  
Quantitative Information ◽  
Isotopic Signature ◽  
Filter Feeder ◽  
Isotopic Signatures ◽  
Fish Predators

The Atlantic blue crab Callinectes sapidus is to date widely distributed in the Mediterranean Sea, where is recognized as an Invasive Alien Species. Noticeably, while records of its occurrence are increasing, quantitative information on its functional role in the benthic food webs of invaded coastal habitats are scarce.Here, carbon and nitrogen isotopic signatures were measured in C. sapidus and other representative taxa of the benthic flora and fauna sampled in summer in the Parila Lagoon, a coastal basin located in the Neretva River estuary area (Croatia). d15N values of individual blue crab specimens were used to calculate their trophic position (TP) , using the filter feeder mussel Mytilus galloprovincialis as the isotopic baseline. In general, the isotopic signature of C. sapidus was comparable with those characterizing invertebrate and fish predators (e.g., Hexaplex trunculus, Gobius niger). An average  trophic position of 3.73 was estimated for the blue crab population. However, a considerable inter-individual variation was observed in TP values, significantly related with the size of the specimens. Interestingly, a hump-shaped quadratic polynomial resulted the best fitting model for the data, characterized for small-size individuals by a positive body size-TP relationship, leveling or even turning negative for larger adult crabs. The interplay between environmental factors and ontogenetic diet shifts in determining the trophic position of the blue crab and, ultimately, its ecological impact on the benthic community of the Parila Lagoon is discussed.  

The Impact of High-Speed Rail on the Spatial Structure of Chinese Urban Agglomerations

2020 ◽  
Vol 46 (3) ◽  
pp. 379-397
Author(s):  
Chunyang Wang
Keyword(s):  
High Speed ◽  
River Delta ◽  
City Size ◽  
High Speed Rail ◽  
Local Conditions ◽  
Urban Agglomerations ◽  
Large Cities ◽  
Spatial Systems ◽  
Economic Concentration ◽  
The Impact

This paper measures the spatial evolution of urban agglomerations to understand be er the impact of high-speed rail (HSR) construction, based on panel data from fi ve major urban agglomerations in China for the period 2004–2015. It is found that there are signi ficant regional diff erences of HSR impacts. The construction of HSR has promoted population and economic diff usion in two advanced urban agglomerations, namely the Yang e River Delta and Pearl River Delta, while promoting population and economic concentration in two relatively less advanced urban agglomerations, e.g. the middle reaches of the Yang e River and Chengdu–Chongqing. In terms of city size, HSR promotes the economic proliferation of large cities and the economic concentration of small and medium-sized cities along its routes. HSR networking has provided a new impetus for restructuring urban spatial systems. Every region should optimize the industrial division with strategic functions of urban agglomeration according to local conditions and accelerate the construction of inter-city intra-regional transport network to maximize the eff ects of high-speed rail across a large regional territory.

The Catholic Diaspora—Experiences of Evacuation

2018 ◽  
Author(s):  
Thomas Brodie
Keyword(s):  
Urban Areas ◽  
Religious Practice ◽  
Catholic Clergy ◽  
Profound Influence ◽  
The Social ◽  
Depth Analysis ◽  
Nazi Era ◽  
Mass Evacuation ◽  
The Impact ◽  
Pastoral Practice

This chapter analyses the impact exerted on the Catholic Church’s pastoral networks in Germany by the mass evacuation of laypeople from bombed urban areas as of 1941. Drawing on the voluminous correspondence of priests and curates despatched from the Rhineland and Westphalia to Saxony, Thuringia, Silesia, Austria, and elsewhere to minister to Catholic evacuees, this chapter provides in-depth analysis of the social and cultural histories of religious practice in wartime Germany. It demonstrates that the evacuation of laypeople—a topic long neglected within histories of wartime religious practice—exerted a profound influence on pastoral practice by the years 1943–5, placing unprecedented pressures on the Catholic clergy of the dioceses central to this study (Aachen, Cologne and Münster). This chapter therefore also casts new light on regionalism in Germany during the Nazi era.

scholarly journals The Impact of Diet on Urinary Risk Factors for Cystine Stone Formation

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 528
Author(s):  
Roswitha Siener ◽  
Norman Bitterlich ◽  
Hubert Birwé ◽  
Albrecht Hesse
Keyword(s):  
Risk Factors ◽  
Dietary Habits ◽  
Sodium Intake ◽  
Stone Formation ◽  
Dietary Treatment ◽  
Vegetarian Diet ◽  
Dietary Sodium ◽  
Urine Ph ◽  
Cystine Stone ◽  
The Impact

Despite the importance of dietary management of cystinuria, data on the contribution of diet to urinary risk factors for cystine stone formation are limited. Studies on the physiological effects of diet on urinary cystine and cysteine excretion are lacking. Accordingly, 10 healthy men received three standardized diets for a period of five days each and collected daily 24 h urine. The Western-type diet (WD; 95 g/day protein) corresponded to usual dietary habits, whereas the mixed diet (MD; 65 g/day protein) and lacto-ovo-vegetarian diet (VD; 65 g/day protein) were calculated according to dietary reference intakes. With intake of the VD, urinary cystine and cysteine excretion decreased by 22 and 15%, respectively, compared to the WD, although the differences were not statistically significant. Urine pH was significantly highest on the VD. Regression analysis showed that urinary phosphate was significantly associated with cystine excretion, while urinary sulfate was a predictor of cysteine excretion. Neither urinary cystine nor cysteine excretion was affected by dietary sodium intake. A lacto-ovo-vegetarian diet is particularly suitable for the dietary treatment of cystinuria, since the additional alkali load may reduce the amount of required alkalizing agents.

scholarly journals Decreased Medical Care During the COVID-19 Pandemic – A Comprehensive Analysis of Radiological Examinations

2021 ◽  
Author(s):  
Annette Aigner ◽  
Bernd Hamm ◽  
Florian Nima Fleckenstein ◽  
Tazio Maleitzke ◽  
Georg Böning ◽  
...  
Keyword(s):  
Medical Care ◽  
Control Period ◽  
Surrogate Marker ◽  
Medical Specialty ◽  
Case Volume ◽  
Medical Specialties ◽  
Key Points ◽  
Depth Analysis ◽  
The Impact ◽  
Radiological Examinations

Objectives As a cross-section discipline within the hospital infrastructure, radiological departments might be able to provide important information regarding the impact of the COVID-19 pandemic on healthcare. The goal of this study was to quantify changes in medical care during the first wave of the pandemic using radiological examinations as a comprehensive surrogate marker and to determine potential future workload. Methods A retrospective analysis of all radiological examinations during the first wave of the pandemic was performed. The number of examinations was compared to time-matched control periods. Furthermore, an in-depth analysis of radiological examinations attributed to various medical specialties was conducted and postponed examinations were extrapolated to calculate additional workload in the near future. Results A total of 596,760 examinations were analyzed. Overall case volumes decreased by an average of 41 % during the shutdown compared to the control period. The most affected radiological modalities were sonography (–54 %), X-ray (–47 %) followed by MRI (–42 %). The most affected medical specialty was trauma and orthopedics (–60 % case volume) followed by general surgery (–49 %). Examination numbers increased during the post-shutdown period leading to a predicted additional workload of up to 22 %. Conclusion This study shows a marked decrease in radiological examinations in total and among several core medical specialties, indicating a significant reduction in medical care during the first COVID-19 shutdown. Key Points: Citation Format

scholarly journals Environmental Changes and Cultural Transitions in SW Iberia during the Early-Mid Holocene

2021 ◽  
Vol 11 (8) ◽  
pp. 3580
Author(s):  
Cristina Val-Peón ◽  
Juan I. Santisteban ◽  
José A. López-Sáez ◽  
Gerd-Christian Weniger ◽  
Klaus Reicherter
Keyword(s):  
Dietary Habits ◽  
Environmental Changes ◽  
Source Area ◽  
Direct Access ◽  
Special Focus ◽  
Early Neolithic ◽  
Archaeological Data ◽  
Local Resources ◽  
Climate Events ◽  
The Impact

The SW coast of the Iberian Peninsula experiences a lack of palaeoenvironmental and archaeological data. With the aim to fill this gap, we contribute with a new palynological and geochemical dataset obtained from a sediment core drilled in the continental shelf of the Algarve coast. Archaeological data have been correlated with our multi-proxy dataset to understand how human groups adapted to environmental changes during the Early-Mid Holocene, with special focus on the Mesolithic to Neolithic transition. Vegetation trends indicate warm conditions at the onset of the Holocene followed by increased moisture and forest development ca. 10–7 ka BP, after which woodlands are progressively replaced by heaths. Peaks of aridity were identified at 8.2 and 7. 5 ka BP. Compositional, textural, redox state, and weathering of source area geochemical proxies indicates abrupt palaeoceanographic modifications and gradual terrestrial changes at 8.2 ka BP, while the 7.5 ka BP event mirrors a decrease in land moisture availability. Mesolithic sites are mainly composed of seasonal camps with direct access to the coast for the exploitation of local resources. This pattern extends into the Early Neolithic, when these sites coexist with seasonal and permanent occupations located in inland areas near rivers. Changes in settlement patterns and dietary habits may be influenced by changes in coastal environments caused by the sea-level rise and the impact of the 8.2 and 7.5 ka BP climate events.

scholarly journals How Does Diet Influence Our Lives? Evaluating the Relationship between Isotopic Signatures and Mortality Patterns in Italian Roman Imperial and Medieval Periods

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3895
Author(s):  
Marica Baldoni ◽  
Alessandra Nardi ◽  
Flavio De Angelis ◽  
Olga Rickards ◽  
Cristina Martínez-Labarga
Keyword(s):  
Middle Ages ◽  
Dietary Habits ◽  
Roman Period ◽  
Survivorship Analysis ◽  
Linear Effect ◽  
Isotopic Signatures ◽  
Carbon Isotopic ◽  
Religious Aspects ◽  
The Relationship ◽  
Source Of Information

The present research investigates the relationship between dietary habits and mortality patterns in the Roman Imperial and Medieval periods. The reconstructions of population dynamics and subsistence strategies provide a fascinating source of information for understanding our history. This is particularly true given that the changes in social, economic, political, and religious aspects related to the transition from the Roman period to the Middle Ages have been widely discussed. We analyzed the isotopic and mortality patterns of 616 individuals from 18 archeological sites (the Medieval Latium sites of Colonna, Santa Severa, Allumiere, Cencelle, and 14 Medieval and Imperial funerary contexts from Rome) to compile a survivorship analysis. A semi-parametric approach was applied, suggesting variations in mortality patterns between sexes in the Roman period. Nitrogen isotopic signatures influenced mortality in both periods, showing a quadratic and a linear effect for Roman Imperial and Medieval populations, respectively. No influence of carbon isotopic signatures has been detected for Roman Imperial populations. Conversely, increased mortality risk for rising carbon isotopic values was observed in Medieval samples.

scholarly journals Corporate Social Responsibility Disclosure: Responding to Investors’ Criticism on Social Media

2021 ◽  
Vol 18 (14) ◽  
pp. 7396
Author(s):  
Yuming Zhang ◽  
Fan Yang
Keyword(s):  
Social Media ◽  
Corporate Social Responsibility ◽  
Social Responsibility ◽  
Social Issues ◽  
Media Criticism ◽  
Csr Communication ◽  
Depth Analysis ◽  
Csr Disclosure ◽  
Corporate Social ◽  
The Impact

Companies use corporate social responsibility (CSR) disclosures to communicate their social and environmental policies, practices, and performance to stakeholders. Although the determinants and outcomes of CSR activities are well understood, we know little about how companies use CSR communication to manage a crisis. The few relevant CSR studies have focused on the pressure on corporations exerted by governments, customers, the media, or the public. Although investors have a significant influence on firm value, this stakeholder group has been neglected in research on CSR disclosure. Grounded in legitimacy theory and agency theory, this study uses a sample of Chinese public companies listed on the Shanghai Stock Exchange to investigate CSR disclosure in response to social media criticism posted by investors. The empirical findings show that investors’ social media criticism not only motivates companies to disclose their CSR activities but also increases the substantiveness of their CSR reports, demonstrating that companies’ CSR communication in response to a crisis is substantive rather than merely symbolic. We also find that the impact of social media criticism on CSR disclosure is heterogeneous. Non-state-owned enterprises, companies in regions with high levels of environmental regulations, and companies in regions with local government concern about social issues are most likely to disclose CSR information and report substantive CSR activities. We provide an in-depth analysis of corporate CSR strategies for crisis management and show that crises initiated by investors on social media provide opportunities for corporations to improve their CSR engagement.

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