Variation In Number Research Articles

Motorpoint Heatmap of the Hamstring Muscles to Facilitate Neuromuscular Electrical Stimulation.

The effectiveness of neuromuscular electrical stimulation (NMES) depends on electrode placement, with placement over the motor points (MPs) being the most effective. This study aimed to determine the MP-distribution and establish a heatmap indicating the probability of finding a MP in different areas of the hamstring (H) muscles. Additionally, inter-individual variations in the number of MPs were investigated. Thirty-one healthy participants (15 females, 16 males), aged 18-65 years, were included. The individual anatomy of the H-muscles, including the biceps femoris (BF), semitendinosus (ST), and semimembranosus (SM), was determined using ultrasound. MPs were located using a MP-search pen. The thigh anatomy was divided into 70 3x3cm areas, and the probability of finding a MP in each area was calculated using the Clopper-Pearson test to create a heatmap. Regression analysis was employed to determine if patient characteristics were associated with the number of MPs. The two best areas, found over BF and ST, exhibited a 39% probability of containing a MP and were significantly more likely to contain a MP compared to 85% of the remaining areas (p < 0.05). Two areas over SM had a 29% probability of containing a MP. BF exhibited a significantly higher number of MPs compared to SM and ST (p < 0.001). Male sex and higher physical activity were independent explanatory factors positively correlated with the number of MPs over BF in the multiple linear regression (R2 = 0.38, p = 0.001). The MP-heatmap of the H-muscles can effectively facilitate NMES application by highlighting areas with a higher probability of finding a MP. Large inter-individual variations in location and number of MPs were demonstrated.

Load adaptive multi-threshold scheduling to concurrently improvise transmission time and wait time performance of C-RAN

Low-latency requirements of 5G networks are one of the fundamental needs to support delay-sensitive applications. Uplink scheduling mechanism at wired midhaul of Centralized Radio Access Network (C-RAN) architecture significantly affects the transmission speed and delay performance of the network. Inadequate performance of conventional scheduling algorithms necessitates improvements to attain these requirements. In this paper, load adaptive scheduling with single threshold (LAS-ST) and load adaptive scheduling with multi-threshold (LAS-MT) algorithms on C-RAN architecture are proposed to reduce transmission time and wait time parameters concurrently. The proposed algorithms have been compared with two conventional scheduling algorithms, multi-scheduling domain (MSD) & single scheduling domain (SSD) and applied at fronthaul and midhaul of C-RAN for its comprehensive analysis. MSD and SSD are widely used in Ethernet Passive Optical Network (EPON) architectures. The results confirm that the proposed multi-threshold scheduling algorithm performs best in meeting the objectives of the studycompared to the existing scheduling algorithms in terms of transmission time and wait time by adapting to conditions. Further, resource utilization and resource availability are observed for several transmission cycles (TCs). In addition, data load variation and variation in number of available resources is analysed and its effect on transmission time and wait time is studied.

Effectual role of plant growth-promoting fungi and fosthiazate in controlling tomato root-knot nematode infection: In vivo and in vitro studies

Plant growth-promoting fungi (PGPF) are known to induce systemic resistance in plant diseases caused by microbial pathogens. However, the induced resistance by PGPF has not yet been elucidated in plant diseases caused by root-knot nematodes (RKNs, Meloidogyne spp.). Meloidogyne incognita can severely damage tomato plants, causing considerable losses in world yields. This study aimed to isolate and evaluate the potential of PGPF through enhancing systemic resistance, possibly through activating defense-related pathways in tomato plants, comparing to the commercial chemical nematicide, Melithorin® (fosthiazate 90 %). The most potent PGPF (K7, K13, K14) were identified morphologically and molecularly as Alternaria photistica, Penicillium buchwaldii, and Aspergillus niger, respectively. We tested the efficacy of these fungi against RKN (M. incognita) both in vitro and in vivo. The results demonstrated that the commercial nematicide fosthiazate (90 %) was the most effective treatment for controlling RKN J2 larvae, achieving a mortality rate of 94 % after 96 h. This was followed by the PGPF treatments, with A. niger at 92.6 %, P. buchwaldii at 87.7 %, Verticillium lecanii at 73.3 %, and A. photistica at 47.4 %. Additionally, applying A. photistica, A. niger, P. buchwaldii, and V. lecanii significantly enhanced the levels of photosynthetic pigments, total carbohydrates, and proteins in both healthy and RKN-infected plants. Notably, Melithorin® (fosthiazate 90 %), A. niger, and V. lecanii led to substantial increases in root carbohydrate content, with increases of 97 %, 63 %, and 58 %, respectively. Furthermore, Melithorin®, A. photistica, and A. niger significantly boosted shoot protein content by 68 %, 65 %, and 49 %, respectively, compared to the infected control group. These findings indicate that both nematicide and fungal treatments effectively reduce nematode populations and improve overall plant health and nutrient composition. At the same time, the results appeared that infected plants treated with PGPF or Melithorin® showed variation in number and molecular weight of protein bands. SDS-PAGE results indicated that, the highest number of bands (twelve) was recorded in the infected plants treated with Melithorin® followed by P. buchwaldii (11 bands), A. photistica (10 bands), V. lecanii (8 bands), and A. niger (7 bands), respectively. Also, the application of Melithorin®, A. niger, and V. lecanii resulted in a significant increase in the number and weight of fruits, respectively, compared to healthy control plants. Our results suggested that A. photistica, A. niger, P. buchwaldii, and V. lecanii could be used as effective and safe nematicides against RKNs.

Effects of small-sided games on some recovery markers in football

Background and Study Aim. Small-sided games (SSGs) are widely used in football training to replicate match conditions while controlling the physical load on players. Variations in the number of players during these games can significantly influence key recovery markers. This study aims to investigate the effects of variations in player numbers on maximal heart rate, blood lactate levels, and perceived exertion in small-sided games acutely applied in football. Material and Methods. The study involved 28 male football players who were also university students (mean age 24.89±4.59 years, mean height 179±0.04 cm, mean body weight 73.21±4.34 kg). The participants were divided into three groups based on the number of players (2 vs. 2, 4 vs. 4, and 8 vs. 8). Heart rate and lactate levels were measured at three time points: before training, immediately after training, and 30 minutes post-training. Results. The study revealed that post-training maximal heart rates (MHR) and lactate levels were significantly higher across all groups compared to pre-training levels, while measurements taken 30 minutes post-training were significantly lower than post-training levels (P&lt;0.05). No significant differences were found between pre-training and 30-minute post-training MHR values across the three groups (P&gt;0.05). Post-training MHR values were similar between the 2 vs. 2 and 4 vs. 4 groups (P&gt;0.05), whereas the 8 vs. 8 group showed significantly higher values (P&lt;0.05). Post-training and 30-minute post-training lactate levels were similar between the 4 vs. 4 and 8 vs. 8 groups (P&gt;0.05), but the 2 vs. 2 group had significantly lower levels (P&lt;0.05). Perceived exertion levels post-training were similar between the 2 vs. 2 and 4 vs. 4 groups (P&gt;0.05), while the 8 vs. 8 group reported significantly higher perceived exertion levels (P&lt;0.05). Conclusions. Small-sided games with varying numbers of players are an effective method for modulating physical load during football training. These findings underscore the importance of considering game format in designing training sessions to optimize player performance and recovery.

Left atrial appendage anatomy: clinical implications for cardiac procedures.

The Left Atrial Appendage (LAA) is the most common source of thrombi during atrial fibrillation (AF) leading to stroke. With the increasing prevalence of AF and the growing number of patients requiring LAA involved interventions like exclusion and ablation, understanding LAA's anatomical intricacies becomes paramount importance. This study aims to provide anatomical data regarding LAA in relation to these procedures. Total 50 formalin-fixed cadaveric hearts were examined and various morphological and morphometric parameters were noted. The Cauliflower shape LAA (36%) was most common followed by Chicken Wing (34%), Cactus (18%), and Windsock (12%) shapes. The LAA orifice had greater horizontal diameter compared to the vertical diameter and was oval in shape in 64% cases. Diverticular structures called divots/ pits were present surrounding the LAA orifice in 36% cases with high variation in number, size, and distance from orifice. They were most commonly present towards the septal side and posterior wall side around the LAA orifice. The circumflex artery was the closest structure to LAA orifice with less than 5mm distance in 76% cases. Other structures present close to the LAA were the Left Superior Pulmonary Vein and Mitral Valve. According to shape, the Non-Chicken Wing morphology of the LAA was associated with close running left circumflex artery, high OI (Ovality Index) of the orifice, and greater presence of divots. The LAA anatomy is complex with high amount of variability making it difficult to perform successful procedures. Given data can help clinicians in better planning and execution of cardiac interventions involving the LAA.

African cichlid fishes: morphological data and taxonomic insights from a genus-level survey of supraneurals, pterygiophores, and vertebral counts (Ovalentaria, Blenniiformes, Cichlidae, Pseudocrenilabrinae).

The iconic freshwater cichlid fishes (Cichlidae) comprise about 1750 validly named species and hundreds more that are known, but not yet described and named. Cichlids are an important source of protein for millions of people on several continents, are model organisms in studies of evolution, speciation, ecology, development, behaviour and physiology and are popular as aquarium fishes. Yet, comparative studies of cichlid internal anatomy are rare. Even their osteology has not been taxonomically surveyed. The cichlid postcranial skeleton has been especially neglected. Here, I provide the first survey in cichlids of the considerable variation in numbers of vertebrae, supraneurals and dorsal- and anal-fin supports (pterygiophores), as well as the patterns with which the pterygiophores insert between the neural or haemal spines. The study includes some 1700 specimens of nearly 400 cichlid species. Focusing on the largest subfamily, the African cichlids or Pseudocrenilabrinae, the survey furnishes data from species in all but one of its 166 genera. Limited data from species in the other cichlid subfamilies (Etroplinae, Ptychochrominae and Cichlinae) and from the related leaffishes, Polycentridae, are also presented. Key examples of pterygiophore insertion patterns from throughout the range of variation are illustrated and discussed. Detailed analytical tables and all raw data are provided in supplementary files.A bizarre specialisation in Cyprichromis is noted, evidently for the first time. Uniquely in this Lake Tanganyikan genus, five to seven anal pterygiophores are abdominal in position, located anterior to the anal fin and inserting toward or between successive pairs of pleural ribs.Taxonomic changes: The most speciose tribe of African cichlids, currently known as Haplochromini, is correctly called Pseudocrenilabrini. Based chiefly on the molecular phylogenetic findings of other workers, I propose four pseudocrenilabrine subtribes, one occurring in rivers and three endemic to Lake Malawi. I also re-assign the Lake Tanganyikan tribe Tropheini as another subtribe of Pseudocrenilabrini, in line with numerous molecular studies placing tropheines firmly within this tribe. The remaining genera of Pseudocrenilabrini remain incertae sedis in this tribe pending clarification of their phylogenetic relationships.The character complex here surveyed is a promising source of taxonomically and phylogenetically informative characteristics distinguishing or uniting cichlid taxa at multiple hierarchical levels, from species through subfamily. This reference set of novel character data can also provide information for palaeontological studies of African cichlids. These attributes are skeletal features potentially available for study in well preserved fossils and may help determine their correct taxonomic placement.

Anti-Malarial Activity of Amentoflavone Isolated from Leaf of Calophyllum Tomentosum Wight.

Calophyllum tomentosum belonging to Clusiaceae family is an Indian medicinal plant used as folklore medicine to cure various kinds of diseases reported in Ayurveda, and the leaves of the plant are also used as an active ingredient for the preparation of a botanical medicine known as 'Punnaga', 'Surapunnaga' and 'Tamoil' among other common names. Chemical profiling of the methanol extract of the defatted leaf revealed the presence of amentoflavone (1) as one of the constituents along with coumarins, terpenoids, steroids, and apetalic acids. Structural determination of amentoflavone (1) has been conducted by chemical, spectral, and spectrometric methods in comparison with spectral values available in the literature and confirmed by a single crystal X-ray diffraction study. Amentoflavone (1) and its derivative (2-5) tested to check the efficacy of anti-malarial activity against Plasmodium falciparum. Amongst them, only tetra methoxy amentoflavone, (2) exhibited moderate anti-malarial activity with IC50 value 1.99±0.42 μM against Plasmodium falciparum in comparison with artemisinin as control, whereas the other products possessed almost negligible activity although their structural skeletons are identical with little variation of number and nature of substituents. The structure activity relationship (SAR) of the active constituent and its derivatives is reported herein.

Trends in American Alligator Pods in Arthur R. Marshall Loxahatchee National Wildlife Refuge

Abstract American alligators are an important component of the Greater Everglades, serving as ecosystem engineers, predator, and prey and are tightly tied to water depth patterns. Because of their importance to ecosystem function and link to hydrology, American alligators are an ecological indicator for Everglades restoration. I used data from fall nighttime spotlight surveys of American alligators in the Arthur R. Marshall Loxahatchee National Wildlife Refuge, Florida, to describe the trend in number of hatchling pods from 1998 to 2021 and relate that trend to hydrologic parameters hypothesized to influence American alligator production. I used an information-theoretic approach to evaluate 14 models created from combinations of year of observation and three hydrologic variables: average and range in water depth from 16 April of the previous year to 15 April of the nesting year (breeding potential window) and average water depth from 16 April to 31 May of the nesting year (courtship and mating window). Number of pods ranged from 16 in 1998 to 0 in 2011. Each of the four top models included year and one or more of the hydrologic variables as predictors and explained 26–34% (D-squared) of the variation in number of pods. Year was the predictor for which the 95% confidence interval (CI) did not contain 0 and indicated a declining trend (from −3 to −8%; 95% CI). I included all hydrologic variables in the top models, indicating that they contribute some information to explaining the trend; however, contrary to my hypotheses, there was not a clear relationship between any of the hydrologic variables and number of American alligator pods. I based my hypotheses on information synthesized in the American alligator production suitability index model used in Everglades restoration planning, and my results suggest the need for additional refinement of that model.

Fetal development and growth of extensor tendons and their sheaths in the dorsal side of the wrist and hand: a histological study.

To understand considerable variations in number of adult extensor ten-dons at the dorsal side of the wrist and hand. We examined histological sections from 30 human fetuses of gestational age 7-39 weeks and crown-rump length 22-323 mm. At the carpal level, earlier or smaller fetuses showed a simpler configuration with fewer tendon slips, whereas later or larger fetuses had a greater number of tendon slips with considerable variations in number and topographical relationships. Tendon slips of the early extensor digitorum to the middle and ring fingers were always 1 or 2, but were seven or more at late term. A tendon of the extensor digitorum to the little fin-ger could not be distinguished from other tendons at the carpal bone level. At the meta-carpal bone level, however, it extended from the ring finger tendon toward two slips of the extensor digiti minimi tendon. At the distal carpal level at midterm and late term, in which the tendon sheath was lost, each of the extensor digitorum tendon slips further divided to provide a mediolateral linear cluster of thin bundles. This large number of tendon components joined and united together to provide a single tight tendon at the level of the metacarpophalangeal joints. The extensor pollicis longs tendon usually lost a membranous septation when it crossed the extensor carpi radialis brevis tendon. Tendon slips in the fourth and fifth canals of the sheath were most likely to reduce in number after birth depending on the mechanical demand.

Design Of A Main Substation Grounding System Based On Variations In Area and Number Of Electrodes

The function of the grounding system is to limit the voltage between equipment and the ground and neutralize the voltage that arises at the ground surface due to fault currents flowing in the ground. An unsafe grounding system can disrupt system reliability and human safety in the substation area. This research aims to simulate the design of a substation grounding system with the influence of variations in location and number of electrodes installed in grids and rods in swampy soil conditions with different soil resistivity values. The impact of these parameters is on the resistance value, touch voltage, and step voltage at a weight of 70 kg by using the CYMGRD application as a medium to see the effectiveness and optimization of whether the substation grounding system with variations in the outside area and variations in the number of electrode rods meets the requirements without exceeding safe limits on systems or humans. This grounding system design is designed for two cases, namely case 1: the maximum touch voltage and maximum step voltage values exceed the permitted touch voltage and maximum step voltage, so conditions like this are included in the criteria for being unsafe and can endanger personnel in the field. Case 2: the touch voltage and step voltage values are smaller than the permitted touch voltage and step voltage values, so this design is included in safe conditions and meets the criteria for a good and safe grounding system.

Evolutionary Dynamics of Satellite DNA Repeats across the Tettigoniidae Family: Insights from Genomic Analysis.

Satellite DNA repeats are repetitive DNA sequences found in eukaryotic genomes, typically consisting of short DNA motifs repeated in tandem arrays. Despite the vast body of literature on satellite DNA repeats in other taxa, investigations specifically targeting Tettigoniidae remain conspicuously absent. Our study aims to fill a critical gap in our understanding of satellitome evolutionary processes shaping Tettigoniidae genomes. Repeatome analysis revealed that the Meconema thalassinum genome comprises 92%, and Phryganogryllacris superangulata had the lowest value of 34%, with an average of 67% in other Tettigoniidae species. The analysis reveals significant variation in the number of satellite DNA repeats across species of the Tettigoniidae family, with M. thalassinum exhibiting the highest count, 246, reported in insects to date and the lowest count, 10, in Pholidoptera griseoptera. Ruspolia dubia and Ruspolia yunnana, which are congeneric species, showcase distinct counts of 104 and 84 families, respectively. Satellite DNA repeats in R. dubia exhibit the highest abundance, constituting 17.2% of the total genome, while the lowest abundance was reported in P. griseoptera, at 5.65%. The genome size correlates weakly with the satellite DNA family count (rs = 0.42, p = 0.29), but a strong correlation exists between satellite abundance and family number (rs = 0.73, p = 0.03). Moreover, the analysis of satellite DNA gain and loss patterns provides insights into the amplification and homogenization of satellite DNA families within the genome, with species-specific repeats exhibiting a positive trend toward amplification. The chromosomal distribution in M. thalassinum displayed that the highest accumulation was observed on Chr12, Chr01, and Chr04, constituting 17.79%, 17.4%, and 17.22% of the total chromosome size, respectively. The chromosome-specific propagation of satellite DNA families was evident, with MthSat01 solely on chromosome 1 and MthSat170 on chromosome 2, sharing 1.64% and 2.33%. The observed conservation and variations in satellite DNA number and abundances, along with distinct patterns of gain and loss, indicate the influence of potentially diverse evolutionary processes shaping the genomic landscape of these insects, which requires further investigation. Furthermore, the differential accumulation of satellite DNA on specific chromosomes implies that potential chromosome-specific functions or structural features influence the retention and proliferation of satellite sequences.

Genome Characterization and Phylogenetic Analysis of Scale Drop Disease Virus Isolated from Asian Seabass (Lates calcarifer).

Scale drop disease virus (SDDV), a double-stranded DNA virus in the family Iridoviridae, has been reported widely in southeast Asian countries as a causative agent of scale drop syndrome (SDS) in Asian seabass. SDS has resulted in high mortality and significant economic losses to the aquaculture industry. This study demonstrated the use of metagenomic methods to investigate bacterial and viral communities present in infected fish tissues and recover a complete genome of the causative agent named SDDV TH7_2019. Characterization of the TH7_2019 genome revealed a genome size of 131 kb with 134 putative ORFs encoding viral proteins potentially associated with host apoptosis manipulation. A comparative genome analysis showed a high degree of amino acid identity across SDDV strains, with variations in number of repeat sequences and mutations within core genes. Phylogenetic analyses indicate a close relationship among SDDV genomes. This research enhances our understanding of the genetic diversity and evolutionary relationship of SDDV, contributing valuable insights for further development of effective control strategies of SDDV.

Penalty shootouts and bitcoin trading

ABSTRACT Soccer is the most popular sport in the world, and bitcoin is a global asset. Penalty shootouts represent an important stage in a soccer match and generate an enormous amount of public interest and attention. Bitcoin trading experiences a significant drop in volume and volatility during penalty shootouts at major international soccer tournaments. After the conclusion of penalty shootouts, the intensity of bitcoin trading exhibits a swift and a strong rebound. Significant fluctuations in trading volume and volatility of bitcoin around penalty shootouts are primarily driven by the variation in number of trades rather than in trade size.

Cancer registration in Iceland for 70 years - incidence, mortality and survival

The Icelandic Cancer Registry (ICR) was founded seventy years ago by the Icelandic Cancer Society. In 2007 the ICR became one of the health registers of the Directorate of Health. In this paper we present cancer incidence, mortality, and survival in Iceland over 70 years. The ICR receives information on cancer diagnoses from histopathological laboratories, the Hospital Discharge Registry and the Cause of Death Registry. Iceland participates in the Nordic cancer database NORDCAN. Because of the small population size, random variation in numbers is very prominent. Therefore, data from ICR are published as five-year averages. For all malignancies combined, age-standardized incidence (ASI) in men rose steadily until around 15 years ago when a decline started. This is in line with prostate- and lung cancer incidence trends. In women, the ASI was lower than in men, but it is still on the rise despite declining lung cancer incidence. ASI for breast cancer, the most common cancer in women, is increasing. Simultaneously, cancer mortality for both sexes has declined in recent years and cancer survival is improving. Population-based cancer registration for over 70 years makes it possible to monitor the epidemiology of cancer in Iceland and compare with other countries. The changes in trends in ASI are in line with changes of cancer risk factors and diagnostic policy. The decline in cancer mortality and improvement in survival reflects advances in cancer treatment as well as effects of early detection and prevention.

Linkage of routinely collected NHS data to evaluate liaison mental health services: challenges and lessons learned.

Liaison mental health services provide mental health care to patients in acute hospital settings. Evaluation of liaison services is challenging due to their heterogeneous organisation and delivery, high case throughput and varied patient case mix. We aimed to link routinely collected National Health Service data from secondary care settings, chosen for their service characteristics, to data from primary care to evaluate hospital-based liaison mental health services in England. We planned to compare patients referred to hospital-based liaison services with comparable patients in the same hospital not referred to liaison services and comparable patients in hospitals without any liaison services. We designed and enacted a methodology to link data from: (1) Hospital Episode Statistics, a database controlled by the National Health Service Digital and (2) ResearchOne, a primary care database controlled by The Phoenix Partnership. Obtaining approvals for the steps prespecified in the methodological protocol took 907 days. Enactment following approvals took 385 days. Data supplied from Hospital Episode Statistics contained 181,063 patients from 6 hospitals (mean=30,177, standard deviation=28,875.86) who matched the inclusion and exclusion criteria. Data supplied from ResearchOne contained 33,666 (18.6%) of these patients from the 6 hospitals (mean=5611, standard deviation=5206.59). Time required for approvals and enactment was attributable to slowness of data handling processes within each data holder and to resolution of technical and organisational queries between them. Variation in number of patients for which data was supplied between databases and between hospitals was attributable to coding inconsistencies and to the limited intersection of patient populations between databases and variation in recording practices between hospitals. Although it is technically feasible to link primary and secondary care data, the current system is challenging, complicated, unnecessarily bureaucratic, time consuming and costly. This limits the number of studies that could be conducted with these rich data sources. This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme as award number 13/58/08.

International imports and climatic filtering drive compositional variation in non‐native insect establishments

AbstractAimInvasions of non‐native insects can have substantial impacts on agriculture, forestry, human health and biodiversity with considerable economic and environmental consequences. To understand the causes of these invasions, it is important to quantify the relative influence of principal drivers such as international imports and climatic effects.LocationNorth America, Chile, Europe, Australia, New Zealand and Japan.Time Period1881–2020.MethodsTo evaluate the relative contributions of various factors in explaining global variation in numbers of non‐native insect establishments in different world regions, we conducted two multivariate regression analyses to quantify temporal changes in family‐level composition and native ranges of established non‐native species in several world regions.ResultsThere were temporal changes in the family‐level composition of non‐native species assemblages. Prior to 1900, invasions were dominated by scale insects, subsequently shifting to a more diverse set of species, except in North America, which had relatively small compositional change over time compared to other regions. Spatial and temporal variation in the composition of established species was associated with differences in the origin of imports and climatic factors, each explaining 26.3% and 27.4% of the total variation, respectively. The analysis of native ranges of non‐native species indicated that there was no consistent temporal variation across all regions. Established species in New Zealand were predominantly native to Australasia and species in North America and Chile were mainly from Europe. Non‐native species in Europe mainly originated from the Nearctic region while those in Japan and Australia generally originated from multiple regions. Climatic factors in the destination regions had a primary effect (66.3%) on variation in the native range of established species, although imports also had substantial effects (45.4%).Main ConclusionsGeographical variation in climate and imports act together as drivers of establishment success for non‐native insects in all six regions.

Vocalizations of the Pekin duck (Anas platyrhynchos domesticus): how stimuli, sex, and social groups affect their vocal repertoire

Pekin ducks are exposed to stressors such as heat stress, enteric pathogens, mycotoxins, and other environmental stressors. We know from wild bird literature that birds communicate through vocalizations. We hypothesized that Pekin ducks would have a diverse repertoire that is affected by the sex, social group, and specific stimuli. We utilized adult Pekin ducks to develop a vocal repertoire. We placed 1 to 4 ducks of varying sexes into a sound chamber with various stimuli used to encourage new vocalizations. Birds were recorded for 20 min with several variations of number and sexes of ducks. Once the ducks were recorded each vocalization that was clipped was named based on a predetermined naming system. We characterized the vocal system of the ducks under each stimulus and social treatment in 4 ways: overall call rates, call diversity, call repertoire, and call spectral properties. In all cases, normality of residuals and homogeneity of variances for GLM and ANOVA models were confirmed using Proc Univariate (SAS v9.4) where a p ≤ 0.05 was considered significant. We found that Pekin ducks produce up to 16 different vocalizations. The treatments had a significant effect on the overall rate of calls given by the ducks (ANOVA: F6,31 = 8.55, p < 0.0001). Ducks produced the most calls by far when someone was sitting in the chamber with them (30.04 ± 4.45 calls/min). For call diversity, we found that there was a significant main effect of hen number (F218 = 12.21, p = 0.0004) but no main effect of drake number (F3,18 = 3.04, p = 0.0555). Cluster analyses indicated that certain types of calls were given under specific conditions. There were generally 6 major clusters of vocal repertoires (R-square = 0.899, Cubic Clustering Criterion = 9.30). Our results suggest that Pekin ducks are affected by the types of stimuli and social environment in how much they vocalize and in the properties of the calls they use. In addition, males and females differ somewhat in the repertoire of the calls they use, and in the spectral properties of their calls.

Analyzing global trade network resilience during economic crises: A model-based exploration of countries' interactions, USDX variation, and number of exporting countries

The global trade network can be viewed from different perspectives. The common ones are the volume of exports and the number of countries that export products. The variation in number of exporting countries for products has been studied over the years. The U.S. dollar has been used for invoicing exportation in global trade, and its variation in values against global currencies negatively affects the volume of exports and the number of exporters. United States dollar indices (USDX) have been globally used to measure the values of global currencies against the U.S. dollar. Many studies have been done on the effect of the global economic crisis on global trade networks. However, scholars have not yet developed a complex dynamical model and established the critical transitional or threshold values that separate the resilient network of exporting countries from a non-resilient one. This study modelled the dynamic representation of a complex network of exporting countries by modifying Lotka-Volterra models. Using the developed model and empirical data USDX and export data of 161 countries from 1971 to 2020, the critical transition values have been calculated for different phases of economic crises. This study references five major crises, revealing that the variation of U.S. dollar indices significantly impacts global network system resilience. It suggests that policies reducing trade restrictions among trading partners are more important than controlling variation in U.S. dollar indices. This information will be crucial in addressing future crises like the Russian-Ukraine conflict.

Observations of Weddell seal (Leptonychotes weddellii) supernumerary nipples

A wide variety of nipple locations and configurations exist among pinnipeds. Like all marine mammals, pinnipeds can have supernumerary nipples that form in utero. Supernumerary nipples have been documented in several species of pinnipeds, the only taxonomic group of marine mammals with variation in nipple number. We document multiple observations (n = 4) of female Weddell seals (Leptonychotes weddellii) with supernumerary nipples in Erebus Bay, Antarctica, including a female Weddell seal with four nipples that was observed nursing two pups. Intraspecific variation in the number of supernumerary nipples observed included both one and two supernumerary nipples. The majority of the observed supernumerary nipples were nursed on by pups, but lactation was unable to be confirmed. These are the first documented observations of supernumerary nipples in Weddell seals.

Maxillary second molar with morphologic variations in number of roots &amp; canals: Literature review &amp; report of two cases

The root canal and root morphologies of maxillary second molars might vary. This article details the endodontic treatment of two cases involving unusual root canal morphology in a maxillary second molar. The first case involved a single root and a single canal, whereas the second case had a single root with two separate canals. A literature review was conducted to clarify the prevalence of anatomical changes in the number of roots and canals in the maxillary second molar. The utilisation of a dental operating microscope facilitated the detection of the canal orifices in both cases. The objective of this study is to increase the knowledge of clinicians regarding the atypical structure of root canals by examining the complex differences found in maxillary second molars.