Search

Studies commonly highlight the informational upside of a board of directors' connections to its external environment. Through their seats on multiple outside boards, directors are positioned to bring valuable informational resources to complex internal tasks on a focal firm. Crafting an ambidextrous strategic orientation is such a task, requiring great informational resourcing from a board to reconcile contradictions of exploration and exploitation. Yet, we assign an important boundary condition to this expectation by unpacking the idea of "busyness" as an important consideration in a board's (in)ability to apply their informational resources. We complement Resource Dependence Theory with insights from bounded rationality and bounded reliability, to challenge the "more is better" assumption of the benefits of outside board seats. We develop corresponding hypotheses on the extent to which busyness of different director types (exemplified here via the busyness of non-executives, executives, and women directors) is related to the ambidextrous strategic orientation of a firm. Our results from a robust longitudinal panel analysis of publicly listed UK firms uncover complex patterns and provide evidence that boards with busy non-executives have a negative influence on the ambidextrous strategic orientation of firms, whereas boards with busy executive directors do not seem to exert an influence. We further find that boards with busy women directors show an inverted U-shaped relation with ambidextrous strategic orientation. We discuss implications for theory and practice. [ABSTRACT FROM AUTHOR]

Abstract In this study, we conducted a survey of newly discovered populations of tuco-tuco (subterranean rodents of the genus Ctenomys) in the Entre Ríos province, in an area characterized by its unexplored nature and its climatic and biogeographic complexity within Argentina, which includes two National Parks. We characterize the nucleotide sequences of the cytochrome-b gene, revealing the presence of seven novel haplotypes within Ctenomys rionegrensis, a species known to inhabit both sides of the Uruguay River. Through Bayesian analyses, we estimated the divergence times of the oldest lineages of C. rionegrensis, as well as those of the haplotypes located east of the Uruguay River, dating back approximately 630,000 years before present (ybp) and 526,000 ybp, respectively. These estimates correspond with significant paleogeographic events in the region. Our findings may raise questions regarding the taxonomic classification of the species and suggest potential modifications to its current endangered status as designated by the International Union for Conservation of Nature (IUCN). Consequently, this research provides valuable insights that may inform future revisions of the species' conservation status and guide the development of informed management strategies/policies.

The puma (Puma concolor Linnaeus, 1771) is the top predator with the widest distribution in America. Since the establishment of European settlers on the American continent, puma populations have experienced significant contractions and reductions in their original distribution. In Argentina, the management of the conflict between humans and pumas (direct persecution and habitat modification) focused on reduction or elimination methods, leading to a drastic contraction, even total eradication, of puma populations as seen in Patagonia and the eastern part of the country. Despite the lack of knowledge about puma population demographic trends, there are taxonomic issues that remain controversial and need to be resolved to implement appropriate management and conservation measures. Therefore, the aim of this study was to genetically characterize puma populations in the central-southern region of Argentina using two mitochondrial markers, evaluate their demographic history, compare our results at a macro-regional level, and discuss our findings in a conservation and management context. A total of 203 individuals were used, and a fragment of the control region and another of ND5 were sequenced. The genetic variability obtained was moderate. Substitution rates for each locus and the tMRCA were calculated from calibrated trees. In a concatenated tree, two main phylogenetic clades were identified (posterior probability = 1), although a reciprocal monophyly was not observed, with a divergence time of 228 thousand years and a 95% CI [117–363 thousand years]. When evaluating population structuring, three genetic clusters were found, one characteristic of the Patagonian region and the others in the central part of the country. Calculating the ФST values for pairs resulted in significant structuring between Patagonia and the rest of the populations, suggesting the arid diagonal as a possible barrier to gene flow. When evaluating the demographic history, neutrality tests would support a recent expansion in Patagonia. These findings are crucial in defining two distinct Management Units (MUs) in the southern part of puma distribution and providing valuable information for management and conservation measures for the species.

El jabalí, el cerdo silvestre y sus híbridos (Sus scrofa) se encuentran entre las especies exóticas invasoras más dañinas y ampliamente distribuidas en el mundo. En la Argentina, el jabalí ocupa casi la mitad de la superficie del país; invade todos los ecosistemas y expande anualmente su distribución. Como en otras partes del planeta donde fue introducido, provoca impactos negativos sobre la biodiversidad, la economía y la salud. Esta especie omnívora amenaza la conservación de otras especies por depredación y competencia, alteración del suelo y perturbación de las interacciones biológicas. El jabalí afecta actividades productivas, y ello genera costos económicos considerables asociados a la mitigación de daños y al manejo de sus poblaciones. Además, la especie puede impactar en la salud pública, dado que es un importante reservorio y diseminador de patógenos. Asimismo, puede impactar de forma positivamente —directa e indirectamente— con actividades como la caza deportiva y la obtención de carne y derivados. Si bien sus impactos están documentados en varias regiones de la Argentina, existen vacíos de información sobre sus efectos económicos sobre las principales actividades productivas y sobre su rol epidemiológico en la salud de la fauna nativa, el ganado y las personas. A nivel país, su manejo y control es limitado e insuficiente, con muy pocos casos exitosos registrados. La dinámica poblacional del jabalí, combinada con otros factores (e.g., cambios en el uso de la tierra y cambio climático), plantea un escenario desafiante a futuro. La Argentina debe enfrentar las amenazas que representa el jabalí desarrollando e implementando una estrategia de manejo a nivel nacional. Para lograr este propósito, es indispensable realizar una planificación cuidadosa y una toma de decisiones orientada a controlar efectivamente las poblaciones de jabalí, a contener su dispersión geográfica y a mitigar sus impactos negativos.

Pig homeostasis is challenged by stressful production practices, like road transportation. Glucocorticoids (GCs) are mediators of reactive homeostasis, and their concentrations are frequently used as a stress indicator. The adrenocortical activity of fattening female and castrated male pigs was monitored over a 5-day longitudinal study. A bi-factorial experimental design was applied on day 2; 18 pigs in pen 1 were transported for 3 h (T; 1.2 m2/pig), and 18 pigs were kept in pen 2 (NT). Ten pigs from each pen were treated with dexamethasone (T-D or NT-D), and eight with saline solution (T-SS or NT-SS). Adrenocortical activity was assessed by measuring the levels of faecal glucocorticoid metabolites (FGMs) and hair cortisol and cortisone. In T-SS pigs, the level of FGMs was higher after transportation than in NT-SS pigs. The level of FGMs of T-D pigs initially increased but then reached similar levels to those of NT-SS sooner than T-SS. In contrast, hair cortisol and cortisone did not respond to the treatments. Nevertheless, the hair cortisone/cortisol ratio increased due to transport and decreased after dexamethasone administration. Daily faecal sampling proved still more reliable than 60-day hair sampling for assessing adrenocortical activity. Transported pigs recovered their adrenocortical baseline levels within 24 h. Dexamethasone attenuated the response to transport.

We report on the synthesis of two fluorescent probes which can be activated by β-Galactosidase (β-Gal) enzymes and/or light. The probes contained 2-nitro-4-oxybenzyl and 3-nitro-4-oxybenzyl fragments, with β-Gal residues linked to C-4. We performed the enzymatic and photoactivation of the probes in a cuvette and compared them, prior to the labeling of Vimentin–Halo fusion protein in live cells with overexpressed β-galactosidase. The dye fluorescence afforded the observation of enzyme activity by means of confocal and super-resolution optical microscopy based on stimulated emission depletion (STED). The tracing of enzymatic activity with the retention of activated fluorescent products inside cells was combined with super-resolution imaging as a tool for use in biomedicine and life science.

Chronic hypertension is a major risk factor for preeclampsia (PE), associated with significant maternal and neonatal morbidity. We previously demonstrated that pregnant stroke-prone spontaneously hypertensive rats (SHRSP) display a spontaneous PE-like phenotype with distinct placental, fetal, and maternal features. Here, we hypothesized that supplementation with alpha lipoic acid (ALA), a potent antioxidant, during early pregnancy could ameliorate the PE phenotype in this model. To test this hypothesis, timed pregnancies were established using 10 to 12-week-old SHRSP females (n = 19–16/group), which were assigned to two treatment groups: ALA (injected intraperitoneally with 25 mg/kg body weight ALA on gestation day (GD1, GD8, and GD12) or control, receiving saline following the same protocol. Our analysis of maternal signs showed that ALA prevented the pregnancy-dependent maternal blood pressure rise (GD14 blood pressure control 169.3 ± 19.4 mmHg vs. 146.1 ± 13.4 mmHg, p = 0.0001) and ameliorated renal function, as noted by the increased creatinine clearance and improved glomerular histology in treated dams. Treatment also improved the fetal growth restriction (FGR) phenotype, leading to increased fetal weights (ALA 2.19 ± 0.5 g vs. control 1.98 ± 0.3 g, p = 0.0074) and decreased cephalization indexes, indicating a more symmetric fetal growth pattern. This was associated with improved placental efficiency, decreased oxidative stress marker expression on GD14, and serum soluble fms-like tyrosine kinase 1 (sFlt1) levels on GD20. In conclusion, ALA supplementation mitigated maternal signs and improved placental function and fetal growth in SHRSP pregnancies, emerging as a promising therapy in pregnancies at high risk for PE.

Virtualization plays a critical role in enriching the user experience in Virtual Reality (VR) by offering heightened realism, increased immersion, safer navigation, and newly achievable levels of interaction and personalization, specifically in indoor environments. Traditionally, the creation of virtual content has fallen under one of two broad categories: manual methods crafted by graphic designers, which are labor-intensive and sometimes lack precision; traditional Computer Vision (CV) and Deep Learning (DL) frameworks that frequently result in semi-automatic and complex solutions, lacking a unified framework for both 3D reconstruction and scene understanding, often missing a fully interactive representation of the objects and neglecting their appearance. To address these diverse challenges and limitations, we introduce the Virtual Experience Toolkit (VET), an automated and user-friendly framework that utilizes DL and advanced CV techniques to efficiently and accurately virtualize real-world indoor scenarios. The key features of VET are the use of ScanNotate, a retrieval and alignment tool that enhances the precision and efficiency of its precursor, supported by upgrades such as a preprocessing step to make it fully automatic and a preselection of a reduced list of CAD to speed up the process, and the implementation in a user-friendly and fully automatic Unity3D application that guides the users through the whole pipeline and concludes in a fully interactive and customizable 3D scene. The efficacy of VET is demonstrated using a diversified dataset of virtualized 3D indoor scenarios, supplementing the ScanNet dataset.

The puma (Puma concolor Linnaeus, 1771) is the top predator with the widest distribution in America. Since the establishment of European settlers on the American continent, puma populations have experienced significant contractions and reductions in their original distribution. In Argentina, the management of the conflict between humans and pumas (direct persecution and habitat modification) focused on reduction or elimination methods, leading to a drastic contraction, even total eradication, of puma populations as seen in Patagonia and the eastern part of the country. Despite the lack of knowledge about puma population demographic trends, there are taxonomic issues that remain controversial and need to be resolved to implement appropriate management and conservation measures. Therefore, the aim of this study was to genetically characterize puma populations in the central-southern region of Argentina using two mitochondrial markers, evaluate their demographic history, compare our results at a macro-regional level, and discuss our findings in a conservation and management context. A total of 203 individuals were used, and a fragment of the control region and another of ND5 were sequenced. The genetic variability obtained was moderate. Substitution rates for each locus and the tMRCA were calculated from calibrated trees. In a concatenated tree, two main phylogenetic clades were identified (posterior probability = 1), although a reciprocal monophyly was not observed, with a divergence time of 228 thousand years and a 95% CI [117-363 thousand years]. When evaluating population structuring, three genetic clusters were found, one characteristic of the Patagonian region and the others in the central part of the country. Calculating the ФST values for pairs resulted in significant structuring between Patagonia and the rest of the populations, suggesting the arid diagonal as a possible barrier to gene flow. When evaluating the demographic history, neutrality tests would support a recent expansion in Patagonia. These findings are crucial in defining two distinct Management Units (MUs) in the southern part of puma distribution and providing valuable information for management and conservation measures for the species. [ABSTRACT FROM AUTHOR]

Simple Summary: Transportation is one of the most stressful situations in pig production. The maximum duration of a journey should be determined considering the pigs' coping capacity. The effect of a typical journey (200 km in Argentina) on pig physiological stress response was assessed using animal-friendly techniques. Fattening pigs (n = 18) were transported for three hours; 10 received a dexamethasone injection 7 h after the end of the journey. A control group (n = 18) was not transported, and 10 individuals received dexamethasone. The levels of faecal glucocorticoid metabolites and hair cortisol and cortisone were measured. The transported pigs had higher levels of faecal glucocorticoid metabolites after transportation than the control group. The level of faecal glucocorticoid metabolites returned to normal values faster in transported pigs treated with dexamethasone than in the control group. The amount of glucocorticoids in their hair was not related to the stressful stimuli; in contrast, the cortisone/cortisol ratio yielded better results. Since glucocorticoid measurements in hair are still a questionable stress biomarker in pigs, further studies are needed to develop animal-based transport protocols. The results showed that pigs were able to cope with a 3 h road trip. In the near future, a non-invasive glucocorticoid analysis could be used to characterize pigs' coping capacity on a farm. Pig homeostasis is challenged by stressful production practices, like road transportation. Glucocorticoids (GCs) are mediators of reactive homeostasis, and their concentrations are frequently used as a stress indicator. The adrenocortical activity of fattening female and castrated male pigs was monitored over a 5-day longitudinal study. A bi-factorial experimental design was applied on day 2; 18 pigs in pen 1 were transported for 3 h (T; 1.2 m2/pig), and 18 pigs were kept in pen 2 (NT). Ten pigs from each pen were treated with dexamethasone (T-D or NT-D), and eight with saline solution (T-SS or NT-SS). Adrenocortical activity was assessed by measuring the levels of faecal glucocorticoid metabolites (FGMs) and hair cortisol and cortisone. In T-SS pigs, the level of FGMs was higher after transportation than in NT-SS pigs. The level of FGMs of T-D pigs initially increased but then reached similar levels to those of NT-SS sooner than T-SS. In contrast, hair cortisol and cortisone did not respond to the treatments. Nevertheless, the hair cortisone/cortisol ratio increased due to transport and decreased after dexamethasone administration. Daily faecal sampling proved still more reliable than 60-day hair sampling for assessing adrenocortical activity. Transported pigs recovered their adrenocortical baseline levels within 24 h. Dexamethasone attenuated the response to transport. [ABSTRACT FROM AUTHOR]

New photostable and bright supramolecular complexes based on cucurbit[7]uril (CB7) host and diketopyrrolopyrole (DPP) guest dyes having two positively charged 4‐(trimethylammonio)phenyl groups were prepared and characterized. The dye core displays large Stokes shift (in H2O, abs./emission max. 480/550 nm; ϵ~19 000, τfl>4 ns), strong binding with the host (~560 nM Kd) and a linker affording fluorescence detection of bioconjugates with antibody and nanobody. Combination of protein‐functionalized DPP dye with CB7 improves photostability and affords up to 12‐fold emission gain. Two‐color confocal and stimulated emission depletion (STED) microscopy with 595 nm or 655 nm STED depletion lasers shows that the presence of CB7 not only leads to improved brightness and image quality, but also results in DPP becoming cell‐permeable. [ABSTRACT FROM AUTHOR]

The single‐molecule localization concept MINFLUX has triggered a reevaluation of the features of fluorophores for attaining nanometer‐scale resolution. MINFLUX nanoscopy benefits from temporally controlled fluorescence ("on"/"off") photoswitching. Combined with an irreversible switching behavior, the localization process is expected to turn highly efficient and quantitative data analysis simple. The potential in the recently reported photoactivable xanthone (PaX) dyes is recognized to extend the list of molecular switches used for MINFLUX with 561 nm excitation beyond the fluorescent protein mMaple. The MINFLUX localization success rates of PaX560, PaX+560, and mMaple are quantitatively compared by analyzing the effective labeling efficiency of endogenously tagged nuclear pore complexes. The PaX dyes prove to be superior to mMaple and on par with the best reversible molecular switches routinely used in single‐molecule localization microscopy. Moreover, the rationally designed PaX595 is introduced for complementing PaX560 in dual color 561 nm MINFLUX imaging based on spectral classification and the deterministic, irreversible, and additive‐independent nature of PaX photoactivation is showcased in fast live‐cell MINFLUX imaging. The PaX dyes meet the demands of MINFLUX for a robust readout of each label position and fill the void of reliable fluorophores dedicated to 561 nm MINFLUX imaging. [ABSTRACT FROM AUTHOR]

We report on the synthesis of two fluorescent probes which can be activated by β-Galactosidase (β-Gal) enzymes and/or light. The probes contained 2-nitro-4-oxybenzyl and 3-nitro-4-oxybenzyl fragments, with β-Gal residues linked to C-4. We performed the enzymatic and photoactivation of the probes in a cuvette and compared them, prior to the labeling of Vimentin–Halo fusion protein in live cells with overexpressed β-galactosidase. The dye fluorescence afforded the observation of enzyme activity by means of confocal and super-resolution optical microscopy based on stimulated emission depletion (STED). The tracing of enzymatic activity with the retention of activated fluorescent products inside cells was combined with super-resolution imaging as a tool for use in biomedicine and life science. [ABSTRACT FROM AUTHOR]

Copyright of Ecologia Austral is the property of Asociacion Argentina de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Virtualization plays a critical role in enriching the user experience in Virtual Reality (VR) by offering heightened realism, increased immersion, safer navigation, and newly achievable levels of interaction and personalization, specifically in indoor environments. Traditionally, the creation of virtual content has fallen under one of two broad categories: manual methods crafted by graphic designers, which are labor-intensive and sometimes lack precision; traditional Computer Vision (CV) and Deep Learning (DL) frameworks that frequently result in semi-automatic and complex solutions, lacking a unified framework for both 3D reconstruction and scene understanding, often missing a fully interactive representation of the objects and neglecting their appearance. To address these diverse challenges and limitations, we introduce the Virtual Experience Toolkit (VET), an automated and user-friendly framework that utilizes DL and advanced CV techniques to efficiently and accurately virtualize real-world indoor scenarios. The key features of VET are the use of ScanNotate, a retrieval and alignment tool that enhances the precision and efficiency of its precursor, supported by upgrades such as a preprocessing step to make it fully automatic and a preselection of a reduced list of CAD to speed up the process, and the implementation in a user-friendly and fully automatic Unity3D application that guides the users through the whole pipeline and concludes in a fully interactive and customizable 3D scene. The efficacy of VET is demonstrated using a diversified dataset of virtualized 3D indoor scenarios, supplementing the ScanNet dataset. [ABSTRACT FROM AUTHOR]

Chronic hypertension is a major risk factor for preeclampsia (PE), associated with significant maternal and neonatal morbidity. We previously demonstrated that pregnant stroke-prone spontaneously hypertensive rats (SHRSP) display a spontaneous PE-like phenotype with distinct placental, fetal, and maternal features. Here, we hypothesized that supplementation with alpha lipoic acid (ALA), a potent antioxidant, during early pregnancy could ameliorate the PE phenotype in this model. To test this hypothesis, timed pregnancies were established using 10 to 12-week-old SHRSP females (n = 19–16/group), which were assigned to two treatment groups: ALA (injected intraperitoneally with 25 mg/kg body weight ALA on gestation day (GD1, GD8, and GD12) or control, receiving saline following the same protocol. Our analysis of maternal signs showed that ALA prevented the pregnancy-dependent maternal blood pressure rise (GD14 blood pressure control 169.3 ± 19.4 mmHg vs. 146.1 ± 13.4 mmHg, p = 0.0001) and ameliorated renal function, as noted by the increased creatinine clearance and improved glomerular histology in treated dams. Treatment also improved the fetal growth restriction (FGR) phenotype, leading to increased fetal weights (ALA 2.19 ± 0.5 g vs. control 1.98 ± 0.3 g, p = 0.0074) and decreased cephalization indexes, indicating a more symmetric fetal growth pattern. This was associated with improved placental efficiency, decreased oxidative stress marker expression on GD14, and serum soluble fms-like tyrosine kinase 1 (sFlt1) levels on GD20. In conclusion, ALA supplementation mitigated maternal signs and improved placental function and fetal growth in SHRSP pregnancies, emerging as a promising therapy in pregnancies at high risk for PE. [ABSTRACT FROM AUTHOR]

We present a new series of photochromic 1,2-bis(2-ethylbenzo[b]thiophen-3-yl)perfluorocyclopentenes with an oxidized benzothiophene core (O) or a nonoxidized one, decorated with mono- (Th1) and bithiophene (Th2) units attached to positions 6 and 6′ (Sy = symmetric) or only to position 6 (As = asymmetric). “Oxidized” compounds have highly fluorescent closed forms emitting in the visible region (yellow to red). The dyes with nonoxidized benzothiophenes possess fluorescent open forms with rather low emission efficiency. The photoswitching kinetics was studied at several wavelengths with UV and visible light. New diarylethenes underwent ring-closure reactions by irradiation with UV light (365 nm, 405 nm), and the reversible ring-opening by irradiation with visible light (470 nm, 530 nm). The on-switching of fluorescence due to the ring-closure reaction was observed also with visible light of 470 nm (to an extent of 10% for compound SyOTh1) and attributed to the Urbach tail effect. Due to a high degree of fluorescence modulation (>270), good fatigue resistance and large fluorescence quantum yield, compound SyOTh1 emerged as a candidate for single-molecule based super-resolution fluorescence microscopy.