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1.
J Hum Evol ; 190: 103498, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581918

RESUMEN

The Homa Peninsula, in southwestern Kenya, continues to yield insights into Oldowan hominin landscape behaviors. The Late Pliocene locality of Nyayanga (∼3-2.6 Ma) preserves some of the oldest Oldowan tools. At the Early Pleistocene locality of Kanjera South (∼2 Ma) toolmakers procured a diversity of raw materials from over 10 km away and strategically reduced them in a grassland-dominated ecosystem. Here, we report findings from Sare-Abururu, a younger (∼1.7 Ma) Oldowan locality approximately 12 km southeast of Kanjera South and 18 km east of Nyayanga. Sare-Abururu has yielded 1754 artifacts in relatively undisturbed low-energy silts and sands. Stable isotopic analysis of pedogenic carbonates suggests that hominin activities were carried out in a grassland-dominated setting with similar vegetation structure as documented at Kanjera South. The composition of a nearby paleo-conglomerate indicates that high-quality stone raw materials were locally abundant. Toolmakers at Sare-Abururu produced angular fragments from quartz pebbles, representing a considerable contrast to the strategies used to reduce high quality raw materials at Kanjera South. Although lithic reduction at Sare-Abururu was technologically simple, toolmakers proficiently produced cutting edges, made few mistakes and exhibited a mastery of platform management, demonstrating that expedient technical strategies do not necessarily indicate a lack of skill or suitable raw materials. Lithic procurement and reduction patterns on the Homa Peninsula appear to reflect variation in local resource contexts rather than large-scale evolutionary changes in mobility, energy budget, or toolmaker cognition.


Asunto(s)
Hominidae , Animales , Kenia , Ecosistema , Evolución Biológica , Carbonatos , Arqueología , Fósiles
2.
Brain Cogn ; 165: 105928, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36459865

RESUMEN

Attentional selection of a second target in a rapid stream of stimuli embedding two targets tends to be briefly impaired when two targets are presented in close temporal proximity, an effect known as an attentional blink (AB). Two target sounds (T1 and T2) were embedded in a rapid serial auditory presentation of environmental sounds with a short (Lag 3) or long lag (Lag 9). Participants were to first identify T1 (bell or sine tone) and then to detect T2 (present or absent). Individual stimuli had durations of either 30 or 90 ms, and were presented in streams of 20 sounds. The T2 varied in category: human voice, cello, or dog sound. Previous research has introduced pupillometry as a useful marker of the intensity of cognitive processing and attentional allocation in the visual AB paradigm. Results suggest that the interplay of stimulus factors is critical for target detection accuracy and provides support for the hypothesis that the human voice is the least likely to show an auditory AB (in the 90 ms condition). For the other stimuli, accuracy for T2 was significantly worse at Lag 3 than at Lag 9 in the 90 ms condition, suggesting the presence of an auditory AB. When AB occurred (at Lag 3), we observed smaller pupil dilations, time-locked to the onset of T2, compared to Lag 9, reflecting lower attentional processing when 'blinking' during target detection. Taken together, these findings support the conclusion that human voices escape the AB and that the pupillary changes are consistent with the so-called T2 attentional deficit. In addition, we found some indication that salient stimuli like human voices could require a less intense allocation of attention, or noradrenergic potentiation, compared to other auditory stimuli.


Asunto(s)
Parpadeo Atencional , Voz , Humanos , Atención/fisiología , Parpadeo , Pupila
3.
Psychol Res ; 87(8): 2559-2582, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37074403

RESUMEN

Musicians' body motion plays a fundamental role in ensemble playing, by supporting sound production, communication, and expressivity. This research investigates how Western classical musicians' head motion during ensemble performances relates to a piece's phrase structure and musicians' empathic perspective taking (EPT) profile. Twenty-four advanced piano and singing students took part in the study, and their EPT score was pre-assessed using the Interpersonal Reactivity Index. High and low EPT duos were formed, and musicians were paired with a co-performer from the same and the other EPT group. Musicians rehearsed Fauré's Automne and Schumann's Die Kartenlegerin, and performed the pieces one time before and three times after rehearsal. Motion capture data of the musicians' front head, audio, and MIDI recordings of the performances were collected and analysed. Similarity in musicians' head motion and tendency to lead/lag their co-performer were computed by extracting, respectively, power and phase difference of the cross-wavelet transforms of the velocity curves of each paired marker. Results demonstrate that the power of interperformer coordination corresponds to the piece's phrase levels and that singer's EPT can impact the leader-follower relationships between musicians, depending on piece and take number. In the Fauré piece, the higher the singer's EPT score, the higher the tendency for the singer to lead and pianist to follow in take 3, and the lower the tendency for the singer to lead and pianist to follow in take 2. These results contribute to a further understanding of the mechanisms underpinning social interactions, by revealing the complexity of the association between empathy and body motion in ensembles in promoting and diffusing leadership between musicians.


Asunto(s)
Música , Canto , Humanos , Empatía , Sonido
4.
J Sport Exerc Psychol ; 45(4): 208-223, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37474118

RESUMEN

Mental effort (intensity of attention) in elite sports has remained a debated topic and a challenging phenomenon to measure. Thus, a quasi-ecological laboratory study was conducted to investigate mental effort in elite rowers as compared with a group of nonelites. Findings suggest that eye-tracking measures-specifically, blink rates and pupil size-can serve as valid indicators of mental effort in physically demanding sport tasks. Furthermore, findings contradict the notion that elite athletes spend less cognitive effort than their lower-level peers. Specifically, elites displayed similar levels of self-reported effort and performance decrement with increasing mental load and significantly more mental effort overall as measured by pupil-size increase (relative to baseline) during rowing trials as compared with the nonelites in the sample. Future studies on eye tracking in sports may include investigations of mental effort in addition to selective attention during physically demanding tasks.


Asunto(s)
Deportes , Humanos , Atletas , Atención , Pupila
5.
Hosp Pharm ; 57(1): 88-92, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35521020

RESUMEN

Objective: Evidence shows that patients with opioid use disorder (OUD) have an increased rate of discharge against medical advice (DAMA) as well as higher rates of hospital readmission. Therefore, the objective of this study was to determine if inpatient initiation of buprenorphine/naloxone in patients with OUD is associated with decreased rates of DAMA. Methods: This was a single center retrospective cohort study conducted at a level 1, academic medical center. The study included patients with OUD admitted to the Internal Medicine service from January through May of both 2018 and 2019 for an admitting diagnosis other than opioid withdrawal. The primary endpoint was rate of DAMA among OUD patients not initiated on opioid agonist therapy compared to those initiated on buprenorphine/naloxone. The secondary endpoint was the association between factors of the initiation process on rates of DAMA. Patients were excluded if they were discharged in less than 24 hours or received intermittent administration of buprenorphine/naloxone. Results: The rate of DAMA in OUD patients not initiated on buprenorphine/naloxone was 13.85% compared to 2.56% in those initiated on buprenorphine/naloxone (P = .048). Conclusion: In OUD patients initiated on buprenorphine/naloxone, the rate of DAMA was significantly lower than those who were not. This data supports the importance of optimizing the opportunity to initiate buprenorphine/naloxone in the acute care setting to minimize withdrawal symptoms therefore reducing the rate of DAMA. Ultimately increasing the ability to adequately treat the primary reason for admission and potentially decreasing readmission rates. Further studies are needed to evaluate this impact as this study is limited to a small sample size therefore lacking adequate power.

6.
J Hum Evol ; 131: 61-75, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31182207

RESUMEN

The archaeological record has documented Oldowan hominin occupation of habitats ranging from open grasslands to riparian forest by 2.0 Ma. Despite this we have a poor understanding of whether hominin foraging behavior varied in different environmental settings. We compared bovid mortality profiles from the two largest Oldowan zooarchaeological samples, one from a grassland (Excavation 1, Kanjera South, Kenya) and another from a woodland (FLK Zinj, Olduvai Gorge, Tanzania) with bovid mortality samples created by African carnivores in different habitats. Kanjera hominins frequently had early access, likely through hunting, to small (size 1 ≤ 23 kg and size 2 = 24-112 kg) juvenile bovids, creating a mortality pattern similar to that created by grassland dwelling carnivores. Kanjera hominins had more mixed access to large (size 3 = 113-340 kg), often juvenile, bovids and frequently scavenged heads. In contrast, previous work has shown that the few small bovids at FLK-Zinj were predominantly older individuals. Prime adults dominated the FLK-Zinj large bovid sample, leading to a mortality pattern similar to that created by carnivores occupying more closed habitats. Variation in bovid body size and mortality profiles between these archaeological assemblages may reflect the challenges of acquiring fauna in open versus closed habitats with a simple hunting toolkit. The heterogeneous woodland habitat of FLK-Zinj would have provided more opportunities to ambush prey, whereas on grasslands with more limited concealment opportunities Kanjera hominins focused their efforts on vulnerable juvenile prey, some likely acquired after short chases.


Asunto(s)
Dieta , Cadena Alimentaria , Fósiles , Rumiantes , Animales , Arqueología , Ambiente , Humanos , Kenia , Paleontología , Tanzanía
7.
Conscious Cogn ; 68: 73-96, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30660927

RESUMEN

During skilled music ensemble performance, a multi-layered network of interaction processes allows musicians to negotiate common interpretations of ambiguously-notated music in real-time. This study investigated the conditions that encourage visual interaction during duo performance. Duos recorded performances of a new piece before and after a period of rehearsal. Mobile eye tracking and motion capture were used in combination to map uni- and bidirectional eye gaze patterns. Musicians watched each other more during temporally-unstable passages than during regularly-timed passages. They also watched each other more after rehearsal than before. Duo musicians may seek visual interaction with each other primarily, but not exclusively, when coordination is threatened by temporal instability. Visual interaction increases as musicians become familiar with the piece, suggesting that they visually monitor each other once a shared interpretation of the piece is established. Visual monitoring of co-performers' movements and attention may facilitate feelings of engagement and high-level creative collaboration.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Conducta Cooperativa , Fijación Ocular/fisiología , Gestos , Relaciones Interpersonales , Música , Percepción Visual/fisiología , Adulto , Medidas del Movimiento Ocular , Femenino , Humanos , Masculino
8.
Curr Psychiatry Rep ; 20(10): 92, 2018 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-30194498

RESUMEN

PURPOSE OF REVIEW: We reviewed research on computer-assisted cognitive-behavior therapy (CCBT) performed in medical settings with the goals of assessing the effectiveness of this newer method of treatment delivery, evaluating the need for clinician support of therapeutic computer programs, and making suggestions for future research and clinical implementation. RECENT FINDINGS: The overall results of randomized, controlled trials suggest that CCBT can be an effective treatment for depression in primary care patients and health care anxiety. Also, it can be a useful component of treatment for somatic conditions including irritable bowel syndrome, diabetes, fibromyalgia, and chronic pain. The amount and type of clinician support needed for maximizing effectiveness remains unclear. CCBT offers promise for overcoming barriers to delivering effective psychotherapy in medical settings. We recommend that next steps for researchers include more definitive studies of the influence of clinician support, investigations focused on implementation in clinical practices, cost-benefit analyses, and use of technological advances.


Asunto(s)
Ansiedad/terapia , Terapia Cognitivo-Conductual , Depresión/terapia , Trastorno Depresivo/terapia , Atención Primaria de Salud , Terapia Asistida por Computador , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
9.
Psychol Res ; 82(6): 1177-1194, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28733769

RESUMEN

Ensemble musicians often exchange visual cues in the form of body gestures (e.g., rhythmic head nods) to help coordinate piece entrances. These cues must communicate beats clearly, especially if the piece requires interperformer synchronization of the first chord. This study aimed to (1) replicate prior findings suggesting that points of peak acceleration in head gestures communicate beat position and (2) identify the kinematic features of head gestures that encourage successful synchronization. It was expected that increased precision of the alignment between leaders' head gestures and first note onsets, increased gesture smoothness, magnitude, and prototypicality, and increased leader ensemble/conducting experience would improve gesture synchronizability. Audio/MIDI and motion capture recordings were made of piano duos performing short musical passages under assigned leader/follower conditions. The leader of each trial listened to a particular tempo over headphones, then cued their partner in at the given tempo, without speaking. A subset of motion capture recordings were then presented as point-light videos with corresponding audio to a sample of musicians who tapped in synchrony with the beat. Musicians were found to align their first taps with the period of deceleration following acceleration peaks in leaders' head gestures, suggesting that acceleration patterns communicate beat position. Musicians' synchronization with leaders' first onsets improved as cueing gesture smoothness and magnitude increased and prototypicality decreased. Synchronization was also more successful with more experienced leaders' gestures. These results might be applied to interactive systems using gesture recognition or reproduction for music-making tasks (e.g., intelligent accompaniment systems).


Asunto(s)
Conducta Cooperativa , Gestos , Música , Desempeño Psicomotor/fisiología , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Adulto Joven
10.
J Anat ; 228(4): 534-60, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26791626

RESUMEN

Nearly all primates are ecologically dependent on trees, but they are nonetheless found in an enormous range of habitats, from highly xeric environments to dense rainforest. Most primates have a relatively 'generalised' skeleton, enabling locomotor flexibility and facilitating other crucial functions, such as manual foraging and grooming. This paper explores the associations between habitat, locomotion and morphology in the forelimbs of cercopithecids (Old World monkeys), contextualising their skeletal ecomorphological patterns with those of other mammals, and complementing functional morphological analyses with phylogenetic comparative techniques. The ecomorphological signals present in the generalised primate postcranium, and how an ancestral arboreal 'bauplan' might be modified to incorporate terrestriality or exploit distinct arboreal substrates, are investigated. Analysis of ecomorphological variation in guenons indicates that terrestrial Chlorocebus species retain core elements of a general guenon form, with modifications for terrestriality that vary by species. Adaptation to different modes of arboreality has also occurred in Cercopithecus. The considerable morphological similarity in the guenons sampled emphasises the importance of generality in the primate postcranium - much forelimb variation appears to have emerged stochastically, with a smaller number of traits having a strong functional signal. Analysis of a broader sample of cercopithecids and comparison with felids, suids and bovids indicates that although the cercopithecid humerus has functional morphological signals that enable specimens to be assigned with a reasonable degree of certainty to habitat groups, there is considerable overlap in the specimens assigned to each habitat group. This probably reflects ecological dependence on trees, even in predominantly terrestrial species, as well as the multiple functions of the forelimb and, in some cases, wide geographic distributions that promote intraspecific variation. The use of phylogenetic correction reduced the discriminatory power of the models, indicating that, like allometry, phylogeny contains important ecomorphological information, and should not necessarily be factored out of analyses.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Cercopithecidae/anatomía & histología , Ecosistema , Miembro Anterior/anatomía & histología , Animales , Conducta Animal , Locomoción , Filogenia
11.
Curr Neurol Neurosci Rep ; 16(4): 40, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27002079

RESUMEN

While over half of women with migraine report improvement during pregnancy, having a history of migraine may increase the chance of negative health outcomes. The state of pregnancy increases the risk of several dangerous secondary headache disorders, especially those associated with hypertensive disorders of pregnancy, and providers need to know the red flags to diagnose and treat emergently. Non-pharmacological migraine treatments can be instituted in advance of pregnancy as many are considered the safest options during pregnancy, but understanding the safety of medications and dietary supplements ensures appropriate care for the refractory migraine patient. New controversy exists over the safety of several historically routine and safe migraine treatment options in pregnancy, such as magnesium, acetaminophen, ondansetron, and butalbital. While it is not clear if breastfeeding decreases the postpartum recurrence of migraine, understanding safe treatment options during lactation can allow women to continue breastfeeding while achieving migraine relief.


Asunto(s)
Lactancia , Trastornos Migrañosos/etiología , Complicaciones del Embarazo , Animales , Femenino , Cefaleas Secundarias , Humanos , Hipertensión , Periodo Posparto , Embarazo
12.
J Hum Evol ; 78: 1-11, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25480104

RESUMEN

We test the performance of two models that use mammalian communities to reconstruct multivariate palaeoenvironments. While both models exploit the correlation between mammal communities (defined in terms of functional groups) and arboreal heterogeneity, the first uses a multiple multivariate regression of community structure and arboreal heterogeneity, while the second uses a linear regression of the principal components of each ecospace. The success of these methods means the palaeoenvironment of a particular locality can be reconstructed in terms of the proportions of heavy, moderate, light, and absent tree canopy cover. The linear regression is less biased, and more precisely and accurately reconstructs heavy tree canopy cover than the multiple multivariate model. However, the multiple multivariate model performs better than the linear regression for all other canopy cover categories. Both models consistently perform better than randomly generated reconstructions. We apply both models to the palaeocommunity of the Upper Laetolil Beds, Tanzania. Our reconstructions indicate that there was very little heavy tree cover at this site (likely less than 10%), with the palaeo-landscape instead comprising a mixture of light and absent tree cover. These reconstructions help resolve the previous conflicting palaeoecological reconstructions made for this site.


Asunto(s)
Ecosistema , Mamíferos/fisiología , Modelos Biológicos , Paleontología/métodos , Animales , Fósiles , Análisis Multivariante , Tanzanía , Árboles
13.
J Hum Evol ; 72: 10-25, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24726228

RESUMEN

Evidence of Oldowan tools by ∼2.6 million years ago (Ma) may signal a major adaptive shift in hominin evolution. While tool-dependent butchery of large mammals was important by at least 2.0 Ma, the use of artifacts for tasks other than faunal processing has been difficult to diagnose. Here we report on use-wear analysis of ∼2.0 Ma quartz and quartzite artifacts from Kanjera South, Kenya. A use-wear framework that links processing of specific materials and tool motions to their resultant use-wear patterns was developed. A blind test was then carried out to assess and improve the efficacy of this experimental use-wear framework, which was then applied to the analysis of 62 Oldowan artifacts from Kanjera South. Use-wear on a total of 23 artifact edges was attributed to the processing of specific materials. Use-wear on seven edges (30%) was attributed to animal tissue processing, corroborating zooarchaeological evidence for butchery at the site. Use-wear on 16 edges (70%) was attributed to the processing of plant tissues, including wood, grit-covered plant tissues that we interpret as underground storage organs (USOs), and stems of grass or sedges. These results expand our knowledge of the suite of behaviours carried out in the vicinity of Kanjera South to include the processing of materials that would be 'invisible' using standard archaeological methods. Wood cutting and scraping may represent the production and/or maintenance of wooden tools. Use-wear related to USO processing extends the archaeological evidence for hominin acquisition and consumption of this resource by over 1.5 Ma. Cutting of grasses, sedges or reeds may be related to a subsistence task (e.g., grass seed harvesting, cutting out papyrus culm for consumption) and/or a non-subsistence related task (e.g., production of 'twine,' simple carrying devices, or bedding). These results highlight the adaptive significance of lithic technology for hominins at Kanjera.


Asunto(s)
Cuarzo , Tecnología/historia , Comportamiento del Uso de la Herramienta , Historia Antigua , Humanos , Kenia , Conducta Social
14.
J Med Ethics ; 40(3): 205-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23579231

RESUMEN

INTRODUCTION: Currently, The nature and scope of Clinical Ethics Protocols (CEPs) in Madrid (Spain) are not well understood. OBJECTIVES: The main objective is to describe the features of 'guideline/recommendation' type CEPs that have been or are being developed by existing Clinical Ethics Committees (CECs) in Madrid. Secondary objectives include characterisation of those CECs that have been the most prolific in reference to CEP creation and implementation and identification of any trends in future CEP development. METHODS: We collected CEPs produced and in process by CECs accredited in the public hospitals in Madrid, Spain, from 1996 to 2008. RESULTS: CECs developed 30 CEPs, with 10 more in process. The most common topic is refusal of treatment (seven CEPs developed; two in process). If CEPs addressing terminal illness, Do-Not-Resuscitate orders and advance directives are placed into a separate 'ethical problems at the end of life' category, this CEP subject emerges as the most common (eight developed; four in process). There is a relationship between the age of the CEC and the development of CEPs (the oldest CECs have developed more CEPs). CECs now seem to be more likely to engage in CEP development. CONCLUSIONS: The CECs in Madrid, Spain, have developed a significant number of CEPs (30 in total and 10 in process) and there is a trend towards continued development. The most frequent topics are ethical problems at the end of life and refusal of treatment by the patient.


Asunto(s)
Protocolos Clínicos/normas , Comités de Ética Clínica , Órdenes de Resucitación/ética , Cuidado Terminal/ética , Negativa del Paciente al Tratamiento , Directivas Anticipadas , Ética Médica , Humanos , Guías de Práctica Clínica como Asunto/normas , España , Cuidado Terminal/normas , Enfermo Terminal
15.
Proc Natl Acad Sci U S A ; 107(22): 10002-7, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20534571

RESUMEN

The manufacture of stone tools and their use to access animal tissues by Pliocene hominins marks the origin of a key adaptation in human evolutionary history. Here we report an in situ archaeological assemblage from the Koobi Fora Formation in northern Kenya that provides a unique combination of faunal remains, some with direct evidence of butchery, and Oldowan artifacts, which are well dated to 1.95 Ma. This site provides the oldest in situ evidence that hominins, predating Homo erectus, enjoyed access to carcasses of terrestrial and aquatic animals that they butchered in a well-watered habitat. It also provides the earliest definitive evidence of the incorporation into the hominin diet of various aquatic animals including turtles, crocodiles, and fish, which are rich sources of specific nutrients needed in human brain growth. The evidence here shows that these critical brain-growth compounds were part of the diets of hominins before the appearance of Homo ergaster/erectus and could have played an important role in the evolution of larger brains in the early history of our lineage.


Asunto(s)
Dieta/historia , Hominidae , Animales , Fósiles , Historia Antigua , Hominidae/fisiología , Humanos , Kenia , Paleontología
16.
PLoS One ; 18(4): e0284396, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37053212

RESUMEN

Two experiments were conducted to test the role of participant factors (i.e., musical sophistication, working memory capacity) and stimulus factors (i.e., sound duration, timbre) on auditory recognition using a rapid serial auditory presentation paradigm. Participants listened to a rapid stream of very brief sounds ranging from 30 to 150 milliseconds and were tested on their ability to distinguish the presence from the absence of a target sound selected from various sound sources placed amongst the distracters. Experiment 1a established that brief exposure to stimuli (60 to 150 milliseconds) does not necessarily correspond to impaired recognition. In Experiment 1b we found evidence that 30 milliseconds of exposure to the stimuli significantly impairs recognition of single auditory targets, but the recognition for voice and sine tone targets impaired the least, suggesting that the lower limit required for successful recognition could be lower than 30 milliseconds for voice and sine tone targets. Critically, the effect of sound duration on recognition completely disappeared when differences in musical sophistication were controlled for. Participants' working memory capacities did not seem to predict their recognition performances. Our behavioral results extend the studies oriented to understand the processing of brief timbres under temporal constraint by suggesting that the musical sophistication may play a larger role than previously thought. These results can also provide a working hypothesis for future research, namely, that underlying neural mechanisms for the processing of various sound sources may have different temporal constraints.


Asunto(s)
Música , Humanos , Estimulación Acústica/métodos , Sonido , Percepción Auditiva , Reconocimiento en Psicología
17.
Pathogens ; 12(9)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37764879

RESUMEN

Tick and tick-borne disease control have been a serious research focus for many decades. In a global climate of increasing acaricide resistance, host immunity against tick infestation has become a much-needed complementary strategy to common chemical control. From the earliest acquired resistance studies in small animal models to proof of concept in large production animals, it was the isolation, characterization, and final recombinant protein production of the midgut antigen Bm86 from the Australian cattle tick strain of Rhipicephalus (Boophilus) microplus (later reinstated as R. (B.) australis) that established tick subunit vaccines as a viable alternative in tick and tick-borne disease control. In the past 37 years, this antigen has spawned numerous tick subunit vaccines (either Bm86-based or novel), and though we are still describing its molecular structure and function, this antigen remains the gold standard for all tick vaccines. In this paper, advances in tick vaccine development over the past three decades are discussed alongside the development of biotechnology, where existing gaps and future directives in the field are highlighted.

18.
Front Psychol ; 14: 1220904, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38187406

RESUMEN

Recent investigations on music performances have shown the relevance of singers' body motion for pedagogical as well as performance purposes. However, little is known about how the perception of voice-matching or task complexity affects choristers' body motion during ensemble singing. This study focussed on the body motion of choral singers who perform in duo along with a pre-recorded tune presented over a loudspeaker. Specifically, we examined the effects of the perception of voice-matching, operationalized in terms of sound spectral envelope, and task complexity on choristers' body motion. Fifteen singers with advanced choral experience first manipulated the spectral components of a pre-recorded short tune composed for the study, by choosing the settings they felt most and least together with. Then, they performed the tune in unison (i.e., singing the same melody simultaneously) and in canon (i.e., singing the same melody but at a temporal delay) with the chosen filter settings. Motion data of the choristers' upper body and audio of the repeated performances were collected and analyzed. Results show that the settings perceived as least together relate to extreme differences between the spectral components of the sound. The singers' wrists and torso motion was more periodic, their upper body posture was more open, and their bodies were more distant from the music stand when singing in unison than in canon. These findings suggest that unison singing promotes an expressive-periodic motion of the upper body.

19.
Hum Mov Sci ; 90: 103113, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37331066

RESUMEN

The current motor literature suggests that extraneous cognitive load may affect performance and kinematics in a primary motor task. A common response to increased cognitive demand, as observed in past studies, might be to reduce movement complexity and revert to previously learned movement patterns, in line with the progression-regression hypothesis. However, according to several accounts of automaticity, motor experts should be able to cope with dual task demands without detriment to their performance and kinematics. To test this, we conducted an experiment asking elite and non-elite rowers to use a rowing ergometer under conditions of varying task load. We employed single-task conditions with low cognitive load (i.e., rowing only) and dual-task conditions with high cognitive load (i.e., rowing and solving arithmetic problems). The results of the cognitive load manipulations were mostly in line with our hypotheses. Overall, participants reduced movement complexity, for example by reverting towards tighter coupling of kinematic events, in their dual-task performance as compared to single-task performance. The between-group kinematic differences were less clear. In contradiction to our hypotheses, we found no significant interaction between skill level and cognitive load, suggesting that the rowers' kinematics were affected by cognitive load irrespective of skill level. Overall, our findings contradict several past findings and automaticity theories, and suggest that attentional resources are required for optimal sports performance.


Asunto(s)
Rendimiento Atlético , Humanos , Fenómenos Biomecánicos , Movimiento/fisiología , Ergometría , Cognición
20.
Science ; 379(6632): 561-566, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36758076

RESUMEN

The oldest Oldowan tool sites, from around 2.6 million years ago, have previously been confined to Ethiopia's Afar Triangle. We describe sites at Nyayanga, Kenya, dated to 3.032 to 2.581 million years ago and expand this distribution by over 1300 kilometers. Furthermore, we found two hippopotamid butchery sites associated with mosaic vegetation and a C4 grazer-dominated fauna. Tool flaking proficiency was comparable with that of younger Oldowan assemblages, but pounding activities were more common. Tool use-wear and bone damage indicate plant and animal tissue processing. Paranthropus sp. teeth, the first from southwestern Kenya, possessed carbon isotopic values indicative of a diet rich in C4 foods. We argue that the earliest Oldowan was more widespread than previously known, used to process diverse foods including megafauna, and associated with Paranthropus from its onset.


Asunto(s)
Evolución Biológica , Dieta , Conducta Alimentaria , Hominidae , Animales , Huesos , Fósiles , Kenia , Plantas , Paleontología
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