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1.
Biology (Basel) ; 13(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38927290

RESUMO

Globally, habitat fragmentation has increased the proximity between wildlife, humans, and emerging predators such as free-ranging dogs. In these fragmented landscapes, encounters between primates and dogs are escalating, with primates often falling victim to dog attacks while navigating patchy landscapes and fragmented forests. We aim to investigate how these primates deal with the simultaneous threats posed by humans and predators, specifically focusing on the adaptive strategies of Central Himalayan langur (CHL) in the landscape of fear. To address this, we conducted a behavioral study on the CHL in an agro-forest landscape, studying them for a total of 3912 h over two consecutive years. Our results indicate that, compared to their most common resting behavior, CHLs allocate more time to feeding and locomotion, and less time to socializing in the presence of humans and predatory dogs. Additionally, they exhibit increased feeding and locomotion and reduced social behavior in agro-forest or open habitats. These behavioral patterns reflect adaptive responses to the landscape of fear, where the presence of predators significantly influences their behavior and resource utilization. This study suggests measures to promote coexistence between humans and wildlife through the integration of effective management strategies that incorporate both ecological and social dimensions of human-wildlife interactions.

2.
Am J Primatol ; : e23565, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37839050

RESUMO

Our understanding of decision-making processes and cognitive biases is ever increasing, thanks to an accumulation of testable models and a large body of research over the last several decades. The vast majority of this work has been done in humans and laboratory animals because these study subjects and situations allow for tightly controlled experiments. However, it raises questions about how this knowledge can be applied to wild animals in their complex environments. Here, we review two prominent decision-making theories, dual process theory and Bayesian decision theory, to assess the similarities in these approaches and consider how they may apply to wild animals living in heterogenous environments within complicated social groupings. In particular, we wanted to assess when wild animals are likely to respond to a situation with a quick heuristic decision and when they are likely to spend more time and energy on the decision-making process. Based on the literature and evidence from our multi-destination routing experiments on primates, we find that individuals are likely to make quick, heuristic decisions when they encounter routine situations, or signals/cues that accurately predict a certain outcome, or easy problems that experience or evolutionary history has prepared them for. Conversely, effortful decision-making is likely in novel or surprising situations, when signals and cues have unpredictable or uncertain relationships to an outcome, and when problems are computationally complex. Though if problems are overly complex, satisficing via heuristics is likely, to avoid costly mental effort. We present hypotheses for how animals with different socio-ecologies may have to distribute their cognitive effort. Finally, we examine the conservation implications and potential cognitive overload for animals experiencing increasingly novel situations caused by current human-induced rapid environmental change.

3.
Zool Stud ; 55: e25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-31966170

RESUMO

Mukesh Kumar, Yuvana S. Priya, Virendra Mathur, Harendra Kumar, and Vadamalai Elangovan (2016) The ultrastructural hair morphology of 09 insectivorous bats such as Pipistrellus coromandra, P. ceylonicus, Scotophilus kuhlii, S. heathii, Hipposideros fulvus, H. lankadiva, Megaderma lyra, Rhinopoma micorphyllum and R. hardwickii were examined through scanning electron microscope to validate the use of hair characteristics as supplemental taxonomic tools for species recognition. The results suggest that the hair characteristics such as scale cuticle, divergence from the shaft and degree of hastateness varied among different species of bats. The coronal divergent scale was found in P. coromandra, P. ceylonicus, H. fulvus, and H. lankadiva while coronal divaricate scale was found in R. micorphyllum and R. hardwickii. However, imbricate type of scale was found in S. kuhlii, S. heathii and M. lyra with different degree of hastateness among them. The different types of hastateness found among these insectivorous bats include unequal hastate, equal hastate, alternate, elongate, rounded, simple, denticulate, acuminate and cusped. The hair characteristics such as hair length, scale length, scale width, scale index and width index differed among different species. However, there was no difference in the structure of scales among dorsal, ventral and neck hairs. The ultrastructural diverseness in the hair morphology of different insectivorous species suggests that the structural features of hairs could be used for species recognition.

4.
Tex Heart Inst J ; 30(2): 130-3, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12809255

RESUMO

We describe the case of a 75-year-old man who presented with a large pericardial effusion and an intrapericardial mass. Malignant thymoma with pericardial involvement was diagnosed by percutaneous pericardial tumor biopsy. The pleural effusion was not malignant. The patient underwent further oncologic evaluation followed by adjunctive chemotherapy and radical extirpation of the tumor. He remains asymptomatic and free of disease 24 months after the procedure. We also discuss the role of percutaneous biopsy in the diagnosis of pericardial diseases.


Assuntos
Pericárdio , Timoma/diagnóstico , Neoplasias do Timo/diagnóstico , Idoso , Biópsia/instrumentação , Biópsia/métodos , Biópsia por Agulha/métodos , Humanos , Masculino , Derrame Pericárdico/etiologia , Timoma/complicações , Timoma/diagnóstico por imagem , Timoma/cirurgia , Neoplasias do Timo/complicações , Neoplasias do Timo/diagnóstico por imagem , Neoplasias do Timo/cirurgia , Ultrassonografia
5.
Cardiovasc Dis ; 7(4): 382-396, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15216241

RESUMO

Gated isotope ventriculograms performed 7 to 12 days postoperatively in 50 aortocoronary bypass patients with perioperative myocardial infarction (POMI) were compared with preoperative contrast ventriculograms. The diagnosis of POMI was based on serial electrocardiograms (EKGs), cardiac enzyme studies, and (99m)Tc-pyrophosphate (PYP) scintigraphy. Seven patients exhibited no new regional wall motion abnormalities. Nine had new areas of localized hypokinesis. The remaining 34 demonstrated localized akinesis or dyskinesis; 12 of these also exhibited a greater than 20% decrease in ejection fraction. The severity of the postoperative wall motion abnormality was paralleled by the intensity of PYP accumulation but not necessarily by the degree of cardiac enzyme elevation. Because they occurred in only 62% of patients, new Q waves were considered an insensitive indicator of POMI. Our study revealed that POMI frequently produces significant changes in left ventricular kinetics. Of the standard techniques utilized, the PYP scan had the greatest predictive value.

6.
Cardiovasc Dis ; 7(3): 246-256, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15216251

RESUMO

In two patients with atypical myxomas of the left atrium, two-dimensional echocardiography furnished valuable diagnostic information. In one patient, who had previously developed an embolism at the right brachial artery, M-mode echocardiography revealed an abnormal band of echoes within the left atrium. Two-dimensional echocardiography showed a globular cluster of echoes that remained within the left atrial cavity throughout the cardiac cycle; left ventricular angiography confirmed the ultrasonic findings of an intraatrial mass. At surgery, a calcified, nonprolapsing myxoma was excised from the interatrial septum. The second patient had clinical as well as M-mode echographic features of mitral stenosis. Cardiac catheterization showed a significant gradient across the mitral valve, but the left ventriculogram was normal except for an unusual pattern of mitral regurgitation. Subsequent two-dimensional echocardiography revealed a mass of echoes that prolapsed through the mitral valve during diastole. At surgery, a left atrial myxoma was found attached to the posterior mitral annulus. Our experience indicates that two-dimensional ultrasound is superior to conventional echocardiography for detecting unusual cardiac masses.

7.
Cardiovasc Dis ; 7(2): 127-136, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15216264

RESUMO

This study characterizes left ventricular performance early after aortic valve replacement for severe isolated aortic regurgitation. Gated radionuclide ventriculography studies in 13 patients showed that left ventricular end-diastolic volume was reduced after surgery and that ejection fraction dropped significantly. Despite the fall in ejection fraction, the postoperative cardiac index was significantly greater than the preoperative value. Radionuclide ventriculography is a useful and reliable means of noninvasively assessing left ventricular function soon after aortic valve replacement for aortic regurgitation.

8.
Cardiovasc Dis ; 5(4): 384-390, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15216042

RESUMO

Results of multistage treadmill tests (TMT) of 57 patients with critical stenosis (>/= 50%) of the left main coronary artery were analyzed. Additional disease was present in the major vessel in three patients (5%), two vessels in 18 patients (32%), and three vessels in 35 patients (61%). The TMT was negative for ischemia in only two patients (4%), positive in 51 (89%), and undetermined in 4 (7%). TMT was strongly positive (>/= 2 mm ST segment depression) in 40 patients (70%), and in 11 (19%) of these, ST depression was >/= 3 mm. Hypotension with exercise was rare and was encountered in only one patient. Arrhythmias were induced with exercise in six patients (10%) and resulted in premature termination of TMT in four. TMT was terminated due to early ST segment depression in 40 patients (70%), in 17 (30%) without chest pain-an unusual finding. Exercise was limited to stage I (Bruce protocol) in 16 (28%), stage II in 26 (46%), stage III in ten (17%), and stage IV in five (9%). Mean exercise tolerance was 298 +/- 22 seconds (SEM). Maximum heart rate (HR) achieved was 76 +/- 2% of their maximal predicted values. Peak double product (systolic BP x HR) was 20490 +/- 830. The data suggest that the TMT is rarely negative in the presence of LM lesions. An early strongly positive response with or without pain should lead one to suspect LM disease. Exercise-induced hypotension is rare. Limited exercise tolerance and/or early ST segment depression in stages I and II of TMT seem to be predictive of the severity of LM lesions.

12.
Cardiovasc Dis ; 4(2): 178-183, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-15216123

RESUMO

A large pulmonary arteriovenous fistula was discovered in a patient with long-standing cyanosis, clubbing and dyspnea, with no other cardiovascular signs or symptoms and a normal chest roentgenogram at the time of cardiac catheterization and pulmonary angiography. The fistula was overshadowed by the cardiac silhouette. Surgical resection was successful. Although rarely undetected on the chest roentgenogram, this potentially lethal malformation should be considered in the differential diagnosis of cyanosis unaccompanied by other cardiovascular signs or symptoms.

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