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Archaeologists have used isotope analysis (δ13C, δ15N) of the collagen of human bones, as well as knowledge of available nutrients, to infer that the diet of the ancient Maya was drawn from the resources of the Maya forest landscape. The interpretations have focused on plant carbohydrates from maize and protein dominated by white-tail deer. The δ15N values of bone collagen suggest that most of the protein requirements of the Maya could have been satisfied with a mixture of wild animal flesh and wild and cultivated plants including beans. Chaya, Cnidoscolus aconitifolius, domesticated before the Spanish conquest, has a high-protein content and the potential to have been a significant contributor to the ancient Maya diet. Chaya is easily propagated, is grown in home gardens by the Maya today, and is a significant part of the local traditional diet. Chaya's stable isotopic composition of carbon (δ13C) resembles that of other terrestrial plants, but its values for nitrogen (δ15N) are significantly higher. Consumption of chaya would result in slightly higher δ15N values in humans than expected from the consumption of terrestrial animals. Thus, chaya is situated well as a component of the complex, diverse, and varied diets of ancient Mesoamericans.
This study investigates a low-profile circularly polarized (CP) antenna using coplanar waveguide feeding. Rectangular-shaped slots and an inverted L-shaped slit are entrenched into the ground plane to enhance the impedance bandwidth of the antenna. Furthermore, the antenna is implemented with six elliptical electromagnetic band gap structures on its substrate to enhance the −10 dB return loss bandwidth and also to generate CP waves. The experimental and theoretical results closely match each other and indicate that a simple and compact design antenna with dimensions of 0.317λ0 × 0.317λ0 × 0.023λ0(λ0 is the operating wavelength at 4.74 GHz in free space) achieves 36.9% (3.91–5.68 GHz) of the −10 dB return loss bandwidth and 9.98% (4.09–4.52 GHz) of the 3-dB axial ratio bandwidth, thus making it a favorable entrant for radio altimeter and wireless avionics infra-communication systems.
A mathematical model is proposed for a revolute joint mechanism with an n-degree of freedom (DOF). The matrix approach is used for finding the relation between two consecutive links to determine desired link parameters such as position, velocity and acceleration using the forward kinematic approach. The matrix approach was confirmed for a proposed 10 DOF revolute type (R-type) human upper limb model with servo motors at each joint. Two DOFs are considered each at shoulder, elbow and wrist joint, followed by four DOF for the fingers. Two DOFs were considered for metacarpophalangeal (mcp) and one DOF each for proximal interphalangeal (pip) and distal interphalangeal (dip) joints. MATLAB script function was used to evaluate the mathematical model for determining kinematic parameters for all the proposed human upper limb model joints. The simplified method for kinematic analysis proposed in this paper will further simplify the dynamic modeling of any mechanism for determining joint torques and hence, easy to design control system for joint movements.
There have been long-standing concerns about communication and safety on the Bethlem site out-of-hours due to its size, acuity and the number of specialist services; these issues were exacerbated by the COVID-19 pandemic. A Quality Improvement Project was designed to address communication and safety concerns from the on-call team at the Bethlem Royal psychiatric hospital out-of-hours through the introduction of weekend safety huddles.
Daily weekend safety huddles were introduced to improve communication regarding workload, acuity, new admissions, seclusion reviews, deteriorating patients; and to improve team cohesiveness and trainee support out-of-hours.
The QIP team involved the deputy medical director, the associate director for speciality units, consultants, the college tutor, specialty registrars and core psychiatry trainees. Prior to initiating the huddles, the QIP team met to decide which specialties to involve, to agree on an agenda and liaise with other sites regarding existing huddles. Once the huddles began in April 2020, the team met periodically to agree next courses of action and to troubleshoot. The huddles initially involved acute services and eventually included CAMHS, Forensic, Older Adults, Specialist Units, all on-call consultants, the on-call registrar, two core trainees, the psychiatric liaison manager and the duty senior nurse.
Data were gathered throughout the QIP using Likert scale surveys which were sent to all junior doctors on the out-of-hours rota. Paper surveys were used initially but were later replaced with Microsoft Forms to ensure anonymity.
The percentage of respondents who answered “most of the time” or “all of the time” increased across all parameters when comparing data from before and after implementation of the safety huddles.
These results included improvement in: understanding of workload and acuity (9% before vs 69% after), discussion of new admissions on site (4% before vs 90% after), discussion of patients with deteriorating mental health (35% before vs 90% after) and physical health (22% before vs 83% after), understanding of number of patients in seclusion (61% before vs 93% after) and feeling part of a cohesive “on-call” team (17% before vs 86% after). In addition, the results suggested a reduction in frequency of safety concerns on site (83% answered at least “sometimes” before vs 62% after).
The results of the final survey demonstrated a measurable and positive impact on communications between the out-of-hours team, improved team cohesiveness and a reduction in safety concerns. The lessons learnt also influenced decisions made in formatting safety huddles at other trust sites.
Paratesticular sarcoma are extremely rare malignant tumours. Unlike other sites, they tend to be lower grade and have higher propensity of lymphatic spread. They tend to fail locally and occasionally in the regional lymph nodes. In the absence of target volume delineation guidelines and technical illustration of conformal planning, we have made an attempt to illustrate conformal planning methodology and define target volume based on current evidence in a case of paratesticular sarcoma.
We are presenting a case of 62-year-old male who presented with 15-cm scrotal swelling and underwent high inguinal orchidectomy with ligation of spermatic cord. Histopathology presented a well-differentiated leiomyosarcoma of epididymis. Post-operative radiotherapy target volume included the tumour bed, ipsilateral inguinal nodes and lower pelvic nodes as the clinical target volume.
Adjuvant radiotherapy using advanced delivery technique such as volumetric arc technique can provide good dose distribution with good sparing of organs at risk. The downside of conformal radiation delivery is that it is a resource-intensive and has no established target volume delineation guidelines.
Cordia sinensis, locally known as ‘Goondi’ in India, is an underexploited multipurpose fruit species found in hot arid regions that is well adapted to drought, salt and hot conditions. The present study was undertaken to collect fruit samples from different locations in the Kachchh region of Gujarat, India, and to determine their field establishment for characterization, conservation and utilization. The maximum distribution of the species was observed in Bhuj (45%) and Mandvi (25%). Field boundaries (35%) and scrub forests (30%) had greater frequencies, whereas backyards had rarer frequencies (10%). The species most commonly occurred on levelled topography (60%) with a soil pH in the range of 8–8.5 (63%). Morphological data of three-year-old plants in the field gene bank showed a maximum coefficient of variation in the number of leaves per plant (66.6), followed by the number of branches per plant (45.62) and collar diameter (27.69). Wide variations were recorded in plant height (121.67–212 cm), spread (118–223 cm2) and the number of branches per plant (6–24.33). Specific accessions were identified for fodder (CBCG-12, CBCG-13 and CBCG-16), early flowering and fruiting (CBCG-12, CBCG-13 and CBCG-14), easier propagation by seeds (CBCG-12 and CBCG-13) and salt tolerance (CBCG-15 and CBCG-16). Preliminary findings and information provided about this species' utilization and other aspects might be useful for future research on its domestication, sole plantation and conservation aspects, improving the exploitation of this species by present and future generations.
Giant cell tumour of the tendon sheath (GCTTS) is the second most common tumour of the hand. Despite surgery, local recurrence after excision has been reported in up to 45% of cases. Post-operative radiotherapy (PORT) has been found to be promising in preventing these recurrences in high-risk group. One of the reservations of PORT is secondary effects of radiation which may cause a decreased range of motion of the affected joint, sensory changes and nail changes. Surface mould brachytherapy can provide a high dose to target volume with a rapid fall of dose to surrounding structures. Despite this, it is less used, the possible reason can be less technical proficiency.
We have technically illustrated surface mould brachytherapy in a case of GCTTS of the left index finger, and compared dosimetrically with more widely used conventional photon and electron external beam radiotherapy.
The 6-MV photon treatment plan with a bolus plan provided the least dose to skin (106%) and phalanges (103%). It has a Homogeneity index (1·06) closest to 1, whereas the Conformity index of all plans was similar. The dose coverage was adequate in all plans. The second-best plan dosimetrically was the surface mould brachytherapy.
Background: Healthcare-associated infections (HAIs) are a major global threat to patient safety. Systematic surveillance is crucial for understanding HAI rates and antimicrobial resistance trends and to guide infection prevention and control (IPC) activities based on local epidemiology. In India, no standardized national HAI surveillance system was in place before 2017. Methods: Public and private hospitals from across 21 states in India were recruited to participate in an HAI surveillance network. Baseline assessments followed by trainings ensured that basic microbiology and IPC implementation capacity existed at all sites. Standardized surveillance protocols for central-line–associated bloodstream infections (CLABSIs) and catheter-associated urinary tract infections (CAUTIs) were modified from the NHSN for the Indian context. IPC nurses were trained to implement surveillance protocols. Data were reported through a locally developed web portal. Standardized external data quality checks were performed to assure data quality. Results: Between May 2017 and April 2019, 109 ICUs from 37 hospitals (29 public and 8 private) enrolled in the network, of which 33 were teaching hospitals with >500 beds. The network recorded 679,109 patient days, 212,081 central-line days, and 387,092 urinary catheter days. Overall, 4,301 bloodstream infection (BSI) events and 1,402 urinary tract infection (UTI) events were reported. The network CLABSI rate was 9.4 per 1,000 central-line days and the CAUTI rate was 3.4 per 1,000 catheter days. The central-line utilization ratio was 0.31 and the urinary catheter utilization ratio was 0.57. Moreover, 3,542 (73%) of 4,742 pathogens reported from BSIs and 868 (53%) of 1,644 pathogens reported from UTIs were gram negative. Also, 1,680 (26.3%) of all 6,386 pathogens reported were Enterobacteriaceae. Of 1,486 Enterobacteriaceae with complete antibiotic susceptibility testing data reported, 832 (57%) were carbapenem resistant. Of 951 Enterobacteriaceae subjected to colistin broth microdilution testing, 62 (7%) were colistin resistant. The surveillance platform identified 2 separate hospital-level HAI outbreaks; one caused by colistin-resistant K. pneumoniae and another due to Burkholderia cepacia. Phased expansion of surveillance to additional hospitals continues. Conclusions: HAI surveillance was successfully implemented across a national network of diverse hospitals using modified NHSN protocols. Surveillance data are being used to understand HAI burden and trends at the facility and national levels, to inform public policy, and to direct efforts to implement effective hospital IPC activities. This network approach to HAI surveillance may provide lessons to other countries or contexts with limited surveillance capacity.
Lifetech Konar-multifunctional occluder is a novel device which is primarily used for the closure of ventricular septal defects. Being “multifunctional”, the occluder has the potential to be useful in various structural cardiac defects.
Materials and methods:
We share our retrospective review from two centres regarding non-conventional usage of multifunctional occluders in CHD. Eight patients who underwent interventions using multifunctional occluders for lesions other than ventricular septal defects between March 2019 to September 2019 were included in the study. The patients were analysed based on demography, the size and type of lesion, procedural success, and development of complications. All patients were followed up in the outpatient department for a minimum period of 6 months.
The median age and weight of the cohort were 3.2 years and 9 kg, respectively. Six patients had patent ductus arteriosus, while one patient had aorto-pulmonary window and one had a coronary arterio-venous fistula. The sizing of the occluders and the procedural approach were based on the underlying pathology. The most commonly used occluder was 6 × 4 mm variant. One patient had successful implantation but had significant intra-device residual flow and was thus replaced by a different occluder. There were no major complications, nor any incidences of device embolisation or malposition. On follow-up, all patients had uneventful course.
Konar-multifunctional occluder can be safely used in lesions other than ventricular septal defects, when needed under specific circumstances. Its unique characteristics make it a versatile choice in a variety of cardiac lesions.
Here we present direct dates of food grains and insights into agricultural strategies adopted by Harappans from a newly excavated Indus site 4MSR (Binjor) in northwestern India. The site revealed Early and Mature Harappan phases delimited by a Transitional phase based on ceramics and archaeological artifacts. The macro-botanical remains revealed that the site was occupied by an agricultural society during the Early phase (~2900−2600 BCE), whereas diversification of the economy including more craft specialization, along with an agricultural advancement was witnessed during the Mature phase (~2500−1800 BCE). The advent of summer crops during the Transitional phase (~2600−2500 BCE) indicates climate amelioration attributed to inception of strong Indian Summer Monsoon (ISM). By the end of Mature phase, millet was recorded due to a change in climatic (relatively lower moisture) conditions or drying of the river channel, which forced the settlers to shift the cropping (agricultural) strategy in the region. Plausibly, this unavailability of water during the end of Mature phase led the settlers to abandon the site in order to migrate somewhere else. The subsistence pattern indicates continuity and change in temporal domain likely owing to changing climatic/environmental conditions, resources and knowledge gained by exchange/trade of cultures over a time period between ~2900 BCE to 1800 BCE.
In this paper, an electromagnetic band gap (EBG) metasurface (MS) superstrate-based circularly polarized antenna for the WiMAX (3.5 GHz) band is proposed. The proposed structure comprises a 2 × 2 slot-loaded rectangular patch MS array that can be perceived as a polarization-dependent EBG MS superstrate. Furthermore, to achieve circular polarization, the proposed antenna has an inclined coupling slot onto the ground with a conventional coplanar waveguide feed line. The proposed antenna has a compact structure with a low profile of 0.037λ0 (λ0 stands for the free-space wavelength at 3.48 GHz) and a ground size of 30 × 30 mm2. The measured results show that the −10 dB impedance bandwidth for the proposed antenna is 34.6% and the 3-dB axial ratio (AR) bandwidth is 6.8% with a peak gain of 3.91 dBi in the desired operating band. Good agreement between the simulated and the measured results verifies the performance of the proposed antenna.
The intensity of turbidite sedimentation over long timescales is driven by sea-level change, tectonically driven rock uplift and climatically modulated sediment delivery rates. This study focuses on understanding the effect of sea-level fluctuations and climatic variability on grain-size variations. The grain size and environmental magnetic parameters of Arabian Sea sediments have been documented using 203 samples, spanning the last 200 ka, obtained from International Ocean Discovery Program (IODP) Site U1457. Grain-size end-member modelling suggests that between ~200 and 130 ka there was an increase in the coarse silt fraction caused by sediment transport following reworking of the Indus Fan and development of deep-sea canyons. The sediment size and enhanced magnetic susceptibility indicate a dominant flux of terrestrial sediments. Sedimentation in the distal Indus Fan at c. 200–130 ka was driven by a drop in sea level that lowered the base level in the Indus and Narmada river systems. The low sea-stand caused incision in the Indus delta, canyons and fan area, which resulted in the transportation of coarser sediment at the drilling site. Magnetic susceptibility and other associated magnetic parameters suggest a large fraction of the sediment was supplied by the Narmada River during ~200–130 ka. Since ~130 ka, clay-dominated sedimentation is attributed to the rise in sea level due to warm and wet climate.
Effects of varying volume fractions of SiC nanoparticle (SiCNP) reinforcement on microstructure and mechanical properties of dissimilar AA2024-T351 and AA7075-T651 joints by friction stir welding (FSW) have been investigated experimentally. A rectangular section edge groove was prepared at the adjoining surfaces of the two plates with the butt configuration before FSW. Initially, four fractional volumes with 0, 5, 8, and 13% of SiCNP are reinforced into the grooves of width, 0, 0.2, 0.3, and 0.5 mm and the FSW was performed with the first and second pass to obtain metal matrix nanocomposite (MMNC) at the weld nugget zone (WNZ). The characterization of microstructure specimens was investigated using optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction technique (XRD). The FSW joint specimen produced with 5 vol% fraction of SiCNP for second pass processing observes a defect-free, homogeneous distribution of SiCNP with a mean grain size of about 2–3 µm at the WNZ and weld joints higher in tensile strength, 411 MPa, yield strength, 252 MPa, and percentage elongation, 14.3. The result shows that varying volume fractions (5, 8, 13%) of the SiCNP after the FSW second pass led to significant grain refinement at the WNZ and higher mechanical properties compared with FSW specimens prepared without SiCNP. Higher hardness of 150 Hv was observed in the WNZ for specimen produced with 13 vol% fraction SiCNP.
Stereotactic body radiotherapy (SBRT) is widely used for the treatment of stage-I non-small cell lung cancer (NSCLC). Patient-specific motion correlated with 4DCT could be essential for hypofractionated SBRT. All patients undergoing SBRT do not require motion management during the dose delivery. The objective of this study was to evaluate which patient may benefit from Gated SBRT.
Materials and methods
Treatment planning of 20 patients of stage-I NSCLC was analysed. Conventional and 4DCT scans were taken. Internal target volume as well as planning target volume (ITV and PTV) were determined in the CT data sets. PTVall phases created using 4DCT data sets and PTV15mm created using conventional CT data were compared. Also, ITVall phases were compared with ITV created from maximum intensity projections (ITVMIP). Suitability of patients for motion management-based treatment delivery was also evaluated.
The average ITVMIP to ITVall phases ratio is 1·06 indicating good agreement between them. Based on the ratio of intensity projections, 9 out of 17 patients were found suitable for our existing gated treatment.
4D CT is the main requirement in SBRT to identify the patients who can benefit from motion management during the dose delivery.
Thin films of insulating Ti1−xNixO2 (x = 0.00, 0.05, 0.10, and 0.15) are synthesized by the spray pyrolysis technique. All the films are seen to crystallize into polycrystalline anatase phase of TiO2. However, weak signature of the NiTiO3 phase is also observed for the films having higher Ni ion concentration. Optical absorption analysis suggests nonmonotonous band gap decrease from 3.67 to 3.59 eV with respect to added concentration of Ni ions unto ‘x’ = 0.10 in the TiO2 matrix. The presence of ferromagnetic ordering at room temperature in Ni incorporated TiO2 films is revealed by M–H measurements. Calculated values of saturation magnetization indicate that the observed ferromagnetism is not due to the presence of Ni clusters or segregation of other ferromagnetic phase. Electrically insulating nature of the films suggests that the observed FM ordering is most probably due to the ferromagnetic interaction between bound magnetic polarons which formed due to the creation of oxygen vacancies or defects.
Grewia tenax locally known as ‘Gangerun’, is an important multipurpose underutilized shrub and potentially threaten species of the Thar Desert of India. Owing to its importance, naturally available germplasm was collected and evaluated for its sustainable utilization in future. Data on individual mother plant, seed characters and soil profile were investigated. Habitat occurrence of G. tenax was found in patches with dominant association of Euphorbia caducifolia across the four districts of western Rajasthan. Individual plant on unprotected area portrayed far lower average height (0.95 m) and canopy area (1.75 m2) than protected area (2.63 m and 13.89 m2) signifying level of browsing pressure on this species in Jaisalmer. Soil samples belonging to Pali region have high organic carbon and low electrical conductivity content than Jaisalmer and Jodhpur. The statistical analysis of seed characters revealed the presence of high coefficient of variation (%) in 100-seed weight (HSW; 27.36) followed by seed length (SL; 8.06) and least in seed breadth (SB; 5.85). The range and mean values of HSW, SL, SB and length:breadth ratio (LBR) were (2.02–7.00 and 3.34 g), (4.36–6.15 and 5.36 mm), (3.73–4.68 and 4.25 mm) and (1.11–1.44 and 1.27), respectively. Significantly positive correlation was observed between SL and LBR (0.73) followed by HSW and SL (0.66). Along with these findings, its economic importance, utilization and conservation are detailed in this paper as to hasten further research on its various aspects for its successful conservation and utilization.
This paper presents the design, analysis, and experimental validation of a miniature modular inchworm robot (MMIR). Inchworm robots are capable of maneuvering in confined spaces due to their small size, a desirable characteristic for surveillance, exploration and search and rescue operations. This paper presents two generations of the MMIR (Version 1—V1 and Version 2—V2) that utilize anisotropic friction skin and an undulatory rectilinear gait to produce locomotion. This paper highlights design improvements and a multi-body dynamics approach to model and simulate the system. The MMIR V2 incorporates a slider-crank four-bar mechanism and a relative body revolute joint to produce high-frequency relative translation and rotation to increase forward velocity and enable turning capabilities. Friction analysis and locomotion experiments were conducted to assess the systems performance on various surfaces, validate the dynamic model and simulation results, and measure the maximum forward velocity. The MMIR V1 and V2 were able to achieve maximum forward velocities of 12.7 mm/s and 137.9 mm/s, respectively. These results are compared to reported results of similar robots published in the literature.
This paper presents a compact microstrip antenna using FR-4 substrate for dual band circularly polarized operation using a modified square ring slot in the ground plane with microstrip line feed. Simulation of the impedance characteristic and radiation characteristic for the proposed antenna is carried out using commercially available HFSS software. The simulated data validate measured results and shows good agreement. Proposed antenna shows an impedance bandwidth (return loss >10 dB) of 50.88% at 5.9 GHz of center frequency and 29.92% at 12.8 GHz of center frequency for lower and upper band, respectively. The 3 dB axial ratio bandwidth for lower and upper band is 26.4 and 3.0%, respectively and measured peak gain for the lower and upper band is found as 3.2 and 3.4 dBic, respectively. The proposed antenna can be suitable for wireless communication in C and Ku bands.
We use variation in real estate prices as exogenous shocks to firms’ debt capacity to study the causal effect of financial flexibility on payout policy. We show that an increase in financial flexibility results in higher dividends, share repurchases, and payout flexibility. We find that a 1-standard-deviation increase in a firms’ collateral value results in 0.26- and 0.55-percentage-point increases in nondiscretionary and discretionary payouts, respectively. This effect is stronger for firms with few investment opportunities. Moreover, highly leveraged firms are more likely to cut dividends in response to a sharp decrease in their financial flexibility.
In this work, the deformation mechanisms underlying the room temperature deformation of the pseudomorphic body centered cubic (BCC) Mg phase in Mg/Nb nanolayered composites are studied. Nanolayered composites comprised of 50% volume fraction of Mg and Nb were synthesized using physical vapor deposition with the individual layer thicknesses h of 5, 6.7, and 50 nm. At the lower layer thicknesses of h = 5 and 6.7 nm, Mg has undergone a phase transition from HCP to BCC such that it formed a coherent interface with the adjoining Nb phase. Micropillar compression testing normal and parallel to the interface plane shows that the BCC Mg nanolayered composite is much stronger and can sustain higher strains to failure than the HCP Mg nanolayered composite. A crystal plasticity model incorporating confined layer slip is presented and applied to link the observed anisotropy and hardening in the deformation response to the underlying slip mechanisms.