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Nurses and paramedics by being the frontline workers of the healthcare profession need to be equipped with the relevant knowledge, skills and protective gears against different forms of infection, including COVID-19. Though the governments and concerned stakeholders have provided P.P.E.s, training and information to protect the healthcare professionals, however until now the scientific literature has virtually not reported the impact of P.P.Es availability, training and practices on the COVID-19 sero-prevalence among the nurses and paramedics.
This study aimed to assess the Impact of P.P.Es availability, training and practices on COVID-19 sero-prevalence among nurses and paramedics in teaching hospitals of Peshawar, Pakistan.
A cross-sectional survey was conducted with a total of 133 nurses and paramedics as subjects of the study.
A univariate analysis was done for four variables. The findings indicate that the healthcare professionals (nurses & paramedics) who have received P.P.Es on time at the start of COVID-19 emergence has fewer chances of contracting the COVID-19 infection (O.R = 0.96); while the odds for P.P.Es supplies was 0.73, and the odds of hand hygiene training was 0.95.
The study concluded that the availability of the P.P.E.s, COVID-19 related training and compliance with W.H.O recommended practices against COVID-19 were instrumental in protection against the infection and its spread.
This study presents the main motivation to investigate the COVID-19 pandemic, a major threat to the whole world from the day when it first emerged in China city of Wuhan. Predictions on the number of cases of COVID-19 are crucial in order to prevent and control the outbreak. In this research study, an artificial neural network with rectifying linear unit-based technique is implemented to predict the number of deaths, recovered and confirmed cases of COVID-19 in Pakistan by using previous data of 137 days of COVID-19 cases from the day 25 February 2020 when the first two cases were confirmed, until 10 July 2020. The collected data were divided into training and test data which were used to test the efficiency of the proposed technique. Furthermore, future predictions have been made by the proposed technique for the next 7 days while training the model on whole available data.
Our present genetic data of Acanthocephala, especially the mitochondrial (mt) genomes, remains very limited. In the present study, the nearly complete mt genome sequences of Sphaerirostris lanceoides (Petrochenko, 1949) was sequenced and determined for the first time based on specimens collected from the Indian pond heron Ardeola grayii (Sykes) (Ciconiiformes: Ardeidae) in Pakistan. The mt genome of S. lanceoides is 13 478 bp in size and contains 36 genes, including 12 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs) and two ribosomal RNA genes (rRNAs). Moreover, in order to clarify the phylogenetic relationship of the genera Centrorhynchus and Sphaerirostris, and to test the systematic position of S. lanceoides in the Centrorhynchidae, the phylogenetic analyses were performed using Bayesian inference and maximum likelihood methods, based on concatenated nucleotide sequences of 12 PCGs, rRNAs and tRNAs. The phylogenetic results further confirmed the monophyly of the order Polymorphida and the paraphyly of the order Echinorhynchida in the class Palaeacanthocephala. Our results also challenged the validity of the genus Sphaerirostris (Polymorphida: Centrorhynchidae) and showed a sister relationship between S. lanceoides and S. picae (Rudolphi, 1819).
A compact dual-polarized monostatic antenna (single radiator for transmit and receive modes) is presented with differential receive mode operation to achieve excellent interport isolation for 2.4 GHz single frequency full-duplex or in-band full-duplex applications. The presented antenna comprises three ports radiating element (patch) and a simple 3 dB/180o ring hybrid coupler has been utilized for differentially excited receive mode operation. The 3 dB/180o ring hybrid coupler acts as a self-interference cancellation (SIC) circuit for effective suppression of RF leakage from the transmit port to provide very high interport decoupling between transmit and receive ports. A compact antenna structure has been realized by using two-layered printed circuit board through vias interconnections of both receive ports of the antenna with inputs of SIC circuit. The validation model of proposed antenna offers more than 95 dB peak interport isolation. Moreover, the experimentally measured interport isolation is better than 70 dB throughout the antenna's 10 dB return-loss impedance bandwidth (BW) of 50 MHz (2.38–2.43 GHz). Furthermore, the recorded isolation is more than 80 dB in 20 MHz BW. The implemented antenna has good radiation characteristics including nice gain and low cross-polarization levels as endorsed by measurements. Same antenna structure with microstrip-T feeds can provide DC isolated ports with same interport RF isolation performance for active antenna applications. Such antenna with DC interport isolation will avoid the requirements of additional series capacitors on transmit and receive ports of antenna.
Parthenium weed is an invasive species in a growing number of countries where it infests numerous crop fields, including sorghum. Two field studies were conducted to quantify the effect of parthenium weed on the performance of grain sorghum at different weed densities (0, 5, 10, 15 and 20 plants m−2) and durations of weed-crop competition (season-long weed-free, weed-free after 2, 4, 6 or 8 weeks, and season-long weedy). Our aim was to identify the density threshold and ideal duration to control parthenium weed in sorghum fields. Both field experiments were planned in a randomised complete block design each with three replications in 2016 and were repeated in 2017. Parthenium weed biomass increased significantly with increasing density and competition duration. The increasing parthenium weed density had a linear negative effect on sorghum growth, yield and yield-contributing traits. The highest yield loss, of up to 66%, was recorded at the highest parthenium weed density of 20 plants m−2 when compared to weed-free treatment. In addition, the season-long competition of this weed with sorghum caused 81% reduction in grain yield over weed-free treatment. According to our results, parthenium weed should be managed below a density of 5 plants m−2 and throughout the crop growth duration in grain sorghum fields as it can cause serious yield losses even at low densities and through strong competition at early as well as late growth stages of the crop.
Studies have shown higher rate of various psychiatric disorders among individuals with substance abuse / dependence. There is little data in developing countries, such as Pakistan, on prevalence of psychiatric co-morbidity in this population and impact on treatment.
To assess the psychiatric co-morbidity among individuals with substance dependence and to determine its demographic associations in patients with substance dependence in Pakistan.
This was a descriptive study conducted at a tertiary care hospital in Pakistan. Participants were 588 individuals with substance dependence admitted to a tertiary care hospital in Pakistan, mainly in male inpatient substance dependence unit. The patients were assessed for psychiatric co-morbidity using DSM IV criteria. Informed consent was obtained. The study was approved by the Institutional Research Committee. The results were obtained by using chi square test on SPSS 17.
Out of 588, 200 patients (34%) were found co-morbid with other psychiatric disorders along with substance dependence. Reason of first substance use and history of previous substance dependence were observed to be significantly associated with co-morbid psychiatric disorders, x2 (48, n = 549) = 112.396, p < 0.01 and x2 (18, n = 588) = 29.66, p = 0.041 respectively.
1. There was high rate of psychiatric co-morbidity among individuals with substance dependence in this sample.
2. Depression, personality disorders and anxiety disorders were the major co-morbid diagnosis among this population.
A spoofing attack on a global navigation satellite system (GNSS) receiver is a threat to a significant community of GNSS users due to the high stakes involved. This paper investigates the use of slope based metrics for the detection of spoofing. The formulation of slope based metrics involves monitoring correlators along with tracking correlators in the receiver's channel, which are slaved to the prompt tracking correlator. In this study, using some candidate metrics, detectors have been formed through the analysis of simulated spoofing attacks. A theoretical variance of each metric has also been calculated as a reference for the threshold. A threshold is estimated using the measured variance from the clean signals, for specific false alarm rate. By using the measured threshold, detectors are formed based on slope metrics. These detectors have been tested using TEXBAT data. The results show that the differential slope metrics have good performance. The results have also been compared with some other techniques of spoofing detection.
This paper presents a two-elements based, dual polarized, single layer, patch antenna array with improved isolation between transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) or simultaneous transmit and receive wireless applications. The differential feeding deployed at the Rx port effectively suppresses the coupling which is termed as self-interference from the Tx port to achieve high Tx–Rx interport isolation. A simple 3 dB/180° ring hybrid coupler with nice amplitude and phase balance characteristics has been used for differential Rx operation. The mathematical description for a differential feeding based self-interference cancellation mechanism is also presented for the proposed dual polarized IBFD antenna array. The measurement results for the implemented prototype of the antenna array demonstrate very nice levels of Tx–Rx interport isolation. The implemented single layer, compact antenna array presents 10 dB return-loss bandwidth of more than 50 MHz for both Tx and Rx ports. The prototype achieves >80 dB peak interport isolation and 75 dB (65 dB) isolation in 20 MHz (50 MHz) bandwidth.
Semiconducting nanostructures such as nanowires (NWs) have been used as building blocks for various types of sensors, energy storage and generation devices, electronic devices and for new manufacturing methods involving printed NWs. The response of these sensing/energy/electronic components and the new fabrication methods depends very much on the quality of NWs and for this reason it is important to understand the growth mechanism of 1D semiconducting nanostructures. This is also important to understand the compatibility of NW growth steps and tools used in the process with these unconventional substrates such as plastic that are used in flexible and large area electronics. Therefore, this Element presents at length discussion about the growth mechanisms, growth conditions and the tools used for the synthesis of NWs. Although NWs from Si, ZnO and carbon nanotubes (CNTs) are included, the discussion is generic and relevant to several other types of NWs as well as heterostructures.
We conceptualize that psychosocial safety climate (PSC) has a positive effect on employees' safety behavior by reducing their psychological distress. A high-level PSC environment reduces psychological distress by eliminating the employees' need for devoting psychological resources toward safety concerns. This preserves psychological resources to be invested in important behaviors i.e., safety compliance and participation. Data were collected from 190 production workers in the oil and gas industry across three states of Malaysia. Results showed strong support for our hypotheses. PSC was negatively linked with psychological distress. Psychological distress predicted safety compliance and participation and mediated the relationship between PSC and safety compliance/participation. Results suggest that in order to improve safety compliance and participation, management in safety-sensitive industries should pay attention to psychosocial factors in the work environment. The implications of these results for safety interventions and further research are discussed.
To verify dose delivery and quality assurance of volumetric-modulated arc therapy (VMAT) for head and neck (H&N) cancer.
The Imaging and Radiation Oncology Core Houston (IROC-H) H&N phantom with thermoluminescent dosimeters (TLDs) and films, were imaged with computed tomography scan and the reconstructed image was transferred to pinnacle treatment planning system (TPS). On TPS, the planning target volume (PTV), secondary target volume (STV) and organ at risk (OAR) were delineated manually and a treatment plan was made. The dose constraints were determined for the concerned organs according to IROC-H prescription. The treatment plan was optimised using adoptive convolution algorithm to improve dose homogeneity and conformity. The dose calculation was performed using C.C Convolution algorithm and a Varian True Beam linear accelerator was used to deliver the treatment plan to the H&N phantom. The delivered radiation dose to the phantom was measured through TLDs and GafChromic external beam radiotherapy 2 (EBT2) films. The dosimetric performance of the VMAT delivery was studied by analysing percent dose difference, isodose line profile and gamma analysis of the TPS-computed dose and linac-delivered doses.
The percent dose difference of 3.8% was observed between the planned and measured doses of TLDs and a 1.5-mm distance to agreement (DTA) was observed by comparing isodose line profiles. Passed the gamma criteria of 3%/3 mm was with good percentages.
The dosimetric performance of VMAT delivery for a challenging H&N radiotherapy can be verified using TLDs and films embedded in an anthropomorphic H&N phantom.
Lactoperoxidase (LPO) is an antimicrobial protein present in milk that plays an important role in natural defence mechanisms during neonatal and adult life. The antimicrobial activity of LPO has been commercially adapted for increasing the shelf life of dairy products. Immobilization of LPO on silver nanoparticles (AgNPs) is a promising way to enhance the antimicrobial activity of LPO. In the current study, LPO was immobilized on AgNPs to form LPO/AgNP conjugate. The immobilized LPO/AgNP conjugate was characterized by various biophysical techniques. The enhanced antibacterial activity of the conjugate was tested against E. coli in culture at 2 h intervals for 10 h. The results showed successful synthesis of spherical AgNPs. LPO was immobilized on AgNPs with agglomerate sizes averaging approximately 50 nm. The immobilized conjugate exhibited stronger antibacterial activity against E. coli in comparison to free LPO. This study may help in increasing the efficiency of lactoperoxidase system and will assist in identifying novel avenues to enhance the stability and antimicrobial function of LPO system in dairy and other industries.
Parasites reside inside or outside their hosts and get host nutrition and blood. Here, we have emphasized economic losses in cattle caused by parasitic diseases due to ecto- and endo- parasites (flies, ticks, mites and helminths). We have outlined different methods/models including economic evaluation techniques and dynamic analysis as a major class, used for the calculation of economic losses caused by parasites in cattle. According to already conducted studies, a decrease in production is mentioned in quantity and percentage while financial losses are expressed in the form of account with respect to per head, herd or for the specific study area. The parasites cause the reduced production and financial losses due to control, treatment and mortality costs. We calculated the average decrease in milk production and organ condemnation as 1.16 L animal−1 day−1 and 12.95%, respectively, from overall cattle parasitic infections. Moreover, the average calculated financial and percentage losses were US$ 50.67 animal−1 year−1 and 17.94%, respectively. Economically important parasitic diseases mentioned here are caused by specific spp. of protozoans and helminths according to data collected from the literature. Protozoan diseases include tick-borne diseases, coccidiosis, neosporosis, trypanosomiasis and cryptosporidiosis. Losses due to tick-borne infections were encountered for decreased milk production, mortality, treatment and control. Losses from coccidiosis were due to decreased weight gain, treatment costs and mortality. While abortion losses were encountered in neosporosis. Trypanosomiasis caused losses due to a decrease in milk yield. Moreover, only diagnostic (conventional or molecular techniques) cost was taken into account for cryptosporidiosis. Economically important nematode parasites are Oesophagostomum spp., Cooperia spp., Trichostrongylus spp., Strongyloides spp., Ostertagia spp. and Haemonchus placei. Due to the zoonotic importance of echinococcosis, Echinococcus granulosus is the most economically important cestode parasite. Losses caused by echinococcosis were due to organ condemnation, carcass weight loss and decreases hide value, milk production and fecundity. While, fascioliasis is one of the most economically important trematodal disease, which causes cirrhosis of the liver due to parasite migration, and thus, the organ becomes inedible. So, it would be helpful for farmers and researchers to approach these methods/models for calculation of parasitic losses and should adopt suitable measures to avoid long-term economic losses.
Accurate three-dimensional dosimetry is essential in modern radiotherapy techniques such as volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). In this research work, the PRESAGE® dosimeter was used as quality assurance (QA) tool for VMAT planning for head and neck (H&N) cancer.
Material and method
Computer tomography (CT) scans of an Image Radiation Oncology Core (IROC) H&N anthropomorphic phantom with both IROC standard insert and PRESAGE® insert were acquired separately. Both CT scans were imported into the Pinnacle (9.4 version) TPS for treatment planning, where the structures [planning target volume (PTV), organs at risk) and thermoluminescent detectors (TLDs) were manually contoured and used to optimise a VMAT plan. Treatment planning was done using VMAT (dual arc: 182°–178°, 178°–182°). Beam profile comparisons and gamma analysis were used to quantify agreement with film, PRESAGE® measurement and treatment planning system (TPS) calculated dose distribution.
The average ratio of TLD measured to calculated doses at the four PTV locations in the H&N phantom were between 0·95 to 0·99 for all three VMAT deliveries. Dose profiles were taken along the left–right, the anterior–posterior and superior–inferior axes, and good agreement was found between the PRESAGE® and Pinnacle profile. The mean value of gamma results for three VMAT deliveries in axial and sagittal planes were found to be 94·24 and 93·16% when compared with film and Pinnacle, respectively. The average values comparing the PRESAGE® results and dose values calculated on Pinnacle were observed to be 95·29 and 94·38% in the said planes, respectively, using a 5%/3 mm gamma criteria.
The PRESAGE® dose measurements and calculated dose of pinnacle show reasonable agreement in both axial and sagittal planes for complex dual arc VMAT treatment plans. In general, the PRESAGE® dosimeter is found to be a feasible QA tool of VMAT plan for H&N cancer treatment.
The present study planned to assess the medicinally important plants in the lower Margalla Hills of Islamabad, Pakistan using scanning electron microscopy of their pollens. Both quantitative and qualitative characters of the pollens were analyzed. The shapes of the pollen were prolate, spheroidal, elliptical, and oblate. Exine sculpturing showed rugulate, scabrate, psilate gemmate, and reticulate ornamentation. The people residing in the rural areas are thought to depend, primarily, on medicinal plant resources for many health care needs. A sample of 140 respondents was selected and interviewed by using a stratified random sampling technique. Results showed that the local communities of lower Margalla Hills are highly dependent on plants to treat various ailments, for example, respiratory (28%), digestive (46%) nervous, circulatory and dermatological problems (6% each), and reproductive problems (8%). The continuous dependence of the local community on ethnomedicinally important plants has led to serious degradation of the natural forest of lower Margalla Hills. Priority-based conservation and sustainable use of these forest resources are necessary, and use of alternative resources will also help in the forest conservation.
This study aimed to examine the dosimetric properties of Gafchromic® EBT3 film and intensity-modulated radiation therapy quality assurance (IMRT QA).
Materials and methods
Beams characteristics dosimetric properties and 20 IMRT plans were created and irradiated on Varian dual-energy DHX-S Linac for 6 and 15 MV energies. EBT3 films were analysed using ‘film Pro QA 2014’ software.
The dosimetric comparison of EBT3 film (for red channel dosimetry) and ionisation ion chamber measurement showed that average deviations of symmetry, flatness, central axis, penumbra (left) and penumbra (right) of dose profile were 0·18, 1·34, 0·49%, 3·68 and 3·61 mm for 6 MV and 0·10, 1·3, 0·45, 2·65 and 2·71 mm for 15 MV, respectively. The blue and green channels dosimetry showed greater dose deviation as compared with red channel. IMRT QA verification plan complied about 95% at all different criteria. Reproducibility, stability and face orientation of film were within 1·4% for red channel.
The results advocate that the film can be used not only for dosimetric assessment but also as a reliable IMRT QA tool.
In non-melanoma skin cancer—that is, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)—brachytherapy treatment is preferred over surgical excision because of cosmetic reasons, acceptability and preference of patients.
Material and methods
Moulds are prepared of wax to match the size of the lesion. This represents the area to be considered in treatment planning. A total of 85 patients who had either SCC or BCC were treated, and all these patients were classified on the basis of age, gender and origin.
Patients were treated with 39 Gy in 13 fractions (biological effective dose=50·7 Gy). In 52 BCC patients, treatment achieved excellent cosmetic results in 49 cases, with 17 of these patients experiencing Grade-1 skin reactions related to treatment in the first 24 weeks of follow-up. A single patient experienced Grade-II hyper-pigmentation reaction in the third week. In 33 SCC patients, treatment achieved excellent cosmetic results in 28 cases, with 17 of these patients experiencing Grade-I reaction in the first 36 weeks after treatment. Among the remaining four patients, only one developed Grade-II hypo-pigmentation and one patient experienced tumour recurrence near the primary site. The overall outcome efficacy of the treatment was 98·8%.
The treatment outcome not only enhances our confidence in brachytherapy but also improves the patient’s satisfaction regarding cosmetic results and curative output achieved by avoiding a surgical procedure for non-melanoma skin cancers.
Manganese (Mn) is one important microelement for plants and the human beings. This study was conducted to evaluate the potential of Mn nutrition in improving the productivity and grain biofortification of wheat. For optimization of Mn seed treatments, seeds were primed with 0.1 and 0.01 M Mn solution, or were coated with 250 and 500 mg Mn kg−1 seed. The optimized treatments were used in the second experiment replicated over time and space. In the first experiment conducted at Faisalabad during 2012–2013, maximum grain yield was recorded with Mn seed priming (0.1 M Mn solution), while maximum grain Mn concentration was recorded with foliar application of 0.75 M Mn solution and seed coating with 250 mg Mn kg−1 seed. In the second experiment, conducted at Faisalabad and Sheikhupura during 2013–2014, and at Faisalabad during 2014–2015, maximum grain yield and grain Mn concentration were recorded from seed priming with 0.1 M Mn solution. Regardless of method, Mn application improved the productivity and grain biofortification of wheat. Overall order of improvement in grain yield was seed priming (3.87 Mg ha−1) > foliar application (3.74 Mg ha−1) > seed coating (3.57 Mg ha−1). Regarding grain Mn concentration, the best treatment was seed priming (41.40 µg g−1) followed by seed coating (39.87 µg g−1) and foliar application (36.94 µg g−1). Maximum net returns and benefit-cost ratio were obtained with Mn seed priming, while maximum marginal rate of return was obtained with Mn seed coating. In conclusion, Mn application through seed treatments was cost effective for improving the productivity and grain biofortification of bread wheat in alkaline calcareous soil.