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1.
Phys Chem Chem Phys ; 26(8): 6977-6983, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38344751

RESUMEN

Covalent organic frameworks can be used for next-generation rechargeable metal-ion batteries due to their controllable spatial and chemical architectures and plentiful elemental reserves. In this study, the arsenic-based covalent organic framework (As-COF) is designed by employing the geometrical symmetry of a semiconducting phosphazene-based covalent organic framework that uses p-phenylenediamine as a linker and hexachorocyclotriphosphazene as an As-containing monomer in a C3-like spatial configuration. The As-COF with engineered nanochannels demonstrates exceptional anodic behavior for potassium (K) and calcium (Ca) ion batteries. It exhibits a high storage capacity of about 914(2039) mA h g-1, low diffusion barriers of 0.12(0.26) eV, low open circuit voltage of 0.23(0.18) V, and a minimal volume expansion of 2.41(2.32)% for K (Ca) ions. These attributes collectively suggest that As-COF could significantly advance high-capacity rechargeable batteries.

2.
Opt Express ; 31(8): 12789-12801, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157432

RESUMEN

Metalenses of adjustable power and ultrathin flat zoom lens system have emerged as a promising and key photonic device for integrated optics and advanced reconfigurable optical systems. Nevertheless, realizing an active metasurface retaining lensing functionality in the visible frequency regime has not been fully explored to design reconfigurable optical devices. Here, we present a focal tunable metalens and intensity tunable metalens in the visible frequency regime through the control of the hydrophilic and hydrophobic behavior of freestanding thermoresponsive hydrogel. The metasurface is comprised of plasmonic resonators embedded on the top of hydrogel which serves as dynamically reconfigurable metalens. It is shown that the focal length can be continuously tuned by adjusting the phase transition of hydrogel, the results reveal that the device is diffraction limited in different states of hydrogel. In addition, the versatility of hydrogel-based metasurfaces is further explored to design intensity tunable metalens, that can dynamically tailor the transmission intensity and confined it into the same focal spot under different states, i.e., swollen and collapsed. It is anticipated that the non-toxicity and biocompatibility make the hydrogel-based active metasurfaces suitable for active plasmonic devices with ubiquitous roles in biomedical imaging, sensing, and encryption systems.

3.
Phys Chem Chem Phys ; 25(3): 2439-2450, 2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36598957

RESUMEN

The advancement of metal-catalyzed copolymers is a formidable challenge for achieving distinct catalytic properties to compete with existing plastic polymers in industrial commodities. Herein, we reveal the roles of electronic and steric environments in the thermodynamic preference of microstructures in ethylene/divinyl formal (DVF) co-polymerization using a Pd catalyst under mild conditions to accommodate the respective industrial applicabilities. The insertion products of DVF result in the alteration of the steric crowding, ultimately favoring the efficient formation of cyclic units having potential applications in the manufacture of high-strength fibers. More specifically, to achieve an improved yield of the end copolymer, we tuned the catalytic activity and regioselectivity through a variety of catalysts during ethylene-DVF co-polymerization. The naphthalene-bridged (P^O)PdMe catalyst was found to be promising in terms of the least hindered (buried volume of 47.8%) environment with the thermodynamic preference of 2,1-insertion with an energy of 5.1 kcal mol-1 among all the Pd-metal based catalysts. The highest activity with moderate energy barriers of the proposed catalyst will open new avenues for achieving a variety of potential applications, which is typically not possible using existing polymerization techniques.

4.
Phys Chem Chem Phys ; 25(6): 4980-4986, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36722853

RESUMEN

Electrode materials with high electrochemical efficiency are required for battery technology that can be used to store renewable energy. Bismuth (Bi) has shown great potential as an electrode material for metal ion batteries due to its large volumetric capacity and reasonable operating potential. However, the cycling performance deteriorates due to the drastic volume changes that occur during alloying and dealloying. Herein, we design a 2D Bi-C metal sheet using density functional theory and investigate the feasibility of this nanosheet for alkali metal ion batteries. The predicted metallic Bi-C monolayer (ML) are highly stable and show sound electrode performance. Moreover, alkali metal atoms exhibit high diffusivities on both sides (Bi and C sides) with low energy barriers of 0.252/0.201, 0.217/0.169, and 0.179/0.136 eV for Li, Na, and K ions, respectively. Furthermore, the Bi-C ML shows high theoretical storage capacities of (485 mA h g-1) for Li and Na and (364 mA h g-1) for K and low open-circuit voltage of 0.12, 0.24, and 0.32 V for Li, Na, and K ions, respectively. These exciting findings show that the predicted Bi-C ML can be used as an anode material for Li-, Na- and K-ion batteries.

5.
Small ; 18(52): e2204302, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36251779

RESUMEN

Photoluminescence (PL) in state-of-the-art 2D materials suffers from narrow spectral coverage, relatively broad linewidths, and poor room-temperature (RT) functionality. The authors report ultra-narrow linewidth photo-emitters (ULPs) across the visible to near-infrared wavelength at RT in polymorphic selenium nanoflakes (SeNFs), synthesized via a hot-pressing strategy. Photo-emitters in NIR exhibit full width at half maximum (Γ) of 330 ± 90 µeV, an order of magnitude narrower than the reported ULPs in 2D materials at 300 K, and decrease to 82 ± 70 µeV at 100 K, with coherence time (τc ) of 21.3 ps. The capping substrate enforced spatial confinement during thermal expansion at 250 °C is believed to trigger a localized crystal symmetry breaking in SeNFs, causing a polymorphic transition from the semiconducting trigonal (t) to quasi-metallic orthorhombic (orth) phase. Fine structure splitting in orth-Se causes degeneracy in defect-associated bright excitons, resulting in ultra-sharp emission. Combined theoretical and experimental findings, an optimal biaxial compressive strain of -0.45% cm-1 in t-Se is uncovered, induced by the coefficient of thermal expansion mismatch at the selenium/sapphire interface, resulting in bandgap widening from 1.74 to 2.23 ± 0.1 eV. This report underpins the underlying correlation between crystal symmetry breaking induced polymorphism and RT ULPs in SeNFs, and their phase change characteristics.

6.
Sensors (Basel) ; 22(7)2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35408303

RESUMEN

Industry 4.0 is a new paradigm of digitalization and automation that demands high data rates and real-time ultra-reliable agile communication. Industrial communication at sub-6 GHz industrial, scientific, and medical (ISM) bands has some serious impediments, such as interference, spectral congestion, and limited bandwidth. These limitations hinder the high throughput and reliability requirements of modern industrial applications and mission-critical scenarios. In this paper, we critically assess the potential of the 60 GHz millimeter-wave (mmWave) ISM band as an enabler for ultra-reliable low-latency communication (URLLC) in smart manufacturing, smart factories, and mission-critical operations in Industry 4.0 and beyond. A holistic overview of 60 GHz wireless standards and key performance indicators are discussed. Then the review of 60 GHz smart antenna systems facilitating agile communication for Industry 4.0 and beyond is presented. We envisage that the use of 60 GHz communication and smart antenna systems are crucial for modern industrial communication so that URLLC in Industry 4.0 and beyond could soar to its full potential.


Asunto(s)
Redes de Comunicación de Computadores , Tecnología Inalámbrica , Comunicación , Industrias , Reproducibilidad de los Resultados
7.
Molecules ; 27(19)2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36234819

RESUMEN

Some soil microbes, with their diverse inhabitance, biologically active metabolites, and endospore formation, gave them characteristic predominance and recognition among other microbial communities. The present study collected ten soil samples from green land, agricultural and marshy soil sites of Khyber Pakhtunkhwa, Pakistan. After culturing on described media, the bacterial isolates were identified through phenotypic, biochemical and phylogenetic analysis. Our phylogenetic analysis revealed three bacterial isolates, A6S7, A1S6, and A1S10, showing 99% nucleotides sequence similarity with Brevibacillus formosus, Bacillus Subtilis and Paenibacillus dendritiformis. The crude extract was prepared from bacterial isolates to assess the anti-bacterial potential against various targeted multidrug-resistant strains (MDRS), including Acinetobacter baumannii (ATCC 19606), Methicillin-resistant Staphylococcus aureus (MRSA) (BAA-1683), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (BAA-2108), Staphylococcus aureus (ATCC 292013), Escherichia coli (ATCC25922) and Salmonella typhi (ATCC 14028). Our analysis revealed that all bacterial extracts possess activity against Gram-negative and Gram-positive bacteria at a concentration of 5 mg/mL, efficiently restricting the growth of E. coli compared with positive control ciprofloxacin. The study concluded that the identified species have the potential to produce antimicrobial compounds which can be used to control different microbial infections, especially MDRS. Moreover, the analysis of the bacterial extracts through GC-MS indicated the presence of different antimicrobial compounds such as propanoic acid, oxalic acid, phenol and hexadecanoic acid.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Antibacterianos/química , Antibacterianos/farmacología , Ciprofloxacina , Mezclas Complejas , Escherichia coli , Pruebas de Sensibilidad Microbiana , Nucleótidos , Ácido Oxálico , Ácido Palmítico , Fenoles , Filogenia , Propionatos , Suelo
8.
Pak J Pharm Sci ; 35(2): 487-492, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35642404

RESUMEN

Escherichia coli is the most studied among those bacteria causing urinary tract infections. This study was aimed to find out antibacterial activity and minimum inhibitory concentration of selected antibacterial agents against E. coli isolates of hospitalized UTI patients. The specimens were inoculated on Eosin Methylene Blue medium. E. coli isolates were identified via colonial morphology, biochemical testing and API-20 kit. The susceptibility pattern of antibacterial agents was determined applying disc diffusion method (Kirby-Bauer) and dilution tube method. Among all, 38.82% (n=158/407) specimens were positive for E. coli, while the rest showed either no growth or exhibited colonies other than E. coli. while observing the susceptibility pattern, Imipenem was found the most effective (73.42%) antibacterial agent, followed by nitrofurantoin (52.53%), cefpirome (44.94%) and tazobactam/ piperacillin (44.94%), whereas the E. coli isolates were highly resistant to sulfamethoxazole/trimethoprim (71.52%), followed by Amoxicillin-clavulanic acid (67.72%), nalidixic acid (66.46%) and Tobramycin (62.03%), when tested by disc diffusion method. The isolates were susceptible to cefpirome (39.87%) and tobramycin (39.87%) and resistant to sulfamethoxazole/trimethoprim (75.32%), followed by levofloxacin (61.39%), when tested by tube dilution method. The study concluded high degree of resistance against Sulfamethoxazole/trimethoprim, in contrast, cephalosporin and Imipenem exhibited good potency which can be recommended for UTI.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Escherichia coli , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Humanos , Imipenem/farmacología , Sulfametoxazol/farmacología , Tobramicina/farmacología , Trimetoprim/farmacología , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
9.
Pak J Pharm Sci ; 35(3(Special)): 897-903, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35791585

RESUMEN

UTIs are majorly caused by species of bacteria in patients of almost all ages. The study was aimed to determine the prevalence rate of uropathogens, its antibiotic susceptibility pattern and associated risk factors. Urine samples were collected from n=470 participants using sterilized containers and were inoculated on culture media. The isolates were identified via gram-staining and biochemical characterization. A total of 43.20% samples were positive. Female contributed the highest prevalence rate, 78.82% as compared to male, 21.18%. The highest prevalence 40.90% was observed in the age-group 31-45, followed by 16-30 with 36.90%. Escherichia coli (47.80%) was the most prevalent, followed by Klebsiella pneumoniae (18.2%), Enterococcus faecalis (12.80%), Pseudomonas aeruginosa (10.30%) and Proteus mirabilis (7.40%). Staphylococcus aureus showed high sensitivity (100%) to amikacin, meropenem, imipenem, fosfomycin, vancomycin, clindamycin and linezolid while in case of E. faecalis, vancomycin and linezolid were highly potent. Amikacin and meropenem showed the highest (100%) potency followed by imipenem While Fosfomycin was highly potent to E. coli, K. pneumoniae, P. mirabilis and P. aeruginosa with potency rate 89.97%, 92.31%, 100% and 100% respectively. In the current study, the positivity rate was highly observed in female. E. coli and K. pneumoniae were found the most ubiquitous for UTI.


Asunto(s)
Fosfomicina , Infecciones Urinarias , Amicacina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Escherichia coli , Femenino , Humanos , Imipenem , Klebsiella pneumoniae , Linezolid , Masculino , Meropenem , Pseudomonas aeruginosa , Factores de Riesgo , Centros de Atención Terciaria , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/epidemiología , Infecciones Urinarias/microbiología , Vancomicina
10.
Mol Biol Rep ; 48(8): 6113-6121, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34374895

RESUMEN

BACKGROUND: Shiga toxin-producing E. coli (STEC) are important foodborne pathogens that causing serious public health consequences worldwide. The present study aimed to estimate the prevalence ratio and to identify the zoonotic potential of E. coli O157 isolates in slaughtered adult sheep, goats, cows and buffaloes. MATERIALS AND METHODS: A total of 400 Recto-anal samples were collected from two targeted sites Rawalpindi and Islamabad. Among them, 200 samples were collected from the slaughterhouse of Rawalpindi included sheep (n = 75) and goats (n = 125). While, 200 samples were collected from the slaughterhouse of Islamabad included cows (n = 120) and buffalos (n = 80). All samples were initially processed in buffered peptone water and then amplified by conventional PCR. Samples positive for E. coli O157 were then streaked onto SMAC media plates. From each positive sample, six different Sorbitol fermented pink-colored colonies were isolated and analyzed again via conventional PCR to confirm the presence of rfbE O157 gene. Isolates positive for rfbE O157 gene were then further analyzed by multiplex PCR for the presence of STEC other virulent genes (sxt1, stx2, eae and ehlyA) simultaneously. RESULTS: Of 400 RAJ samples only 2 (0.5%) showed positive results for E. coli O157 gene, included sheep 1/75 (1.33%) and buffalo 1/80 (1.25%). However, goats (n = 125) and cows (n = 120) found negative for E. coli O157. Only 2 isolates from each positive sample of sheep (1/6) and buffalo (1/6) harbored rfbE O157 genes, while five isolates could not. The rfbE O157 isolate (01) of sheep sample did not carry any of STEC genes, while the rfbE O157 isolate (01) of buffalo sample carried sxt1, stx2, eae and ehlyA genes simultaneously. CONCLUSION: It was concluded that healthy adult sheep and buffalo are possibly essential carriers of STEC O157. However, rfbE O157 isolate of buffalo RAJ sample carried 4 STEC virulent genes, hence considered an important source of STEC infection to humans and environment which should need to devise proper control systems.


Asunto(s)
Infecciones por Escherichia coli/diagnóstico , Escherichia coli Shiga-Toxigénica/genética , Escherichia coli Shiga-Toxigénica/aislamiento & purificación , Animales , Búfalos/genética , Bovinos/genética , Escherichia coli/genética , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/veterinaria , Escherichia coli O157/genética , Escherichia coli O157/aislamiento & purificación , Escherichia coli O157/patogenicidad , Proteínas de Escherichia coli/genética , Heces , Cabras/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Pakistán , Prevalencia , Ovinos/genética , Escherichia coli Shiga-Toxigénica/patogenicidad , Virulencia/genética , Factores de Virulencia/genética
11.
Curr Microbiol ; 78(10): 3644-3655, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34480627

RESUMEN

Continuously increasing human population demands increased food production, which needs greater fertilizer's input in agricultural lands to enhance crop yield. In this respect, different fertilization practices gained acceptance among farmers. We reviewed effect of three main fertilization practices (Conventional-, Organic-, and Bio-fertilization) on soil microbial diversity, activity, and community composition. Studies reported that over application of inorganic fertilizers decline soil pH, change soil osmolarity, cause soil degradation, disturb taxonomic diversity and metabolism of soil microbes and cause accumulation of extra nutrients into the soil such as phosphorous (P) accumulation. On the contrary, organic fertilizers increase organic carbon (OC) input in the soil, which strongly encourage growth of heterotrophic microbes. Organic fertilizer vermicompost application provides readily available nutrients to both plants as well as microbes and encourage overall microbial number in the soil. Most recently, role of beneficial bacteria in long-term sustainable agriculture attracted attention of scientists towards their use as biofertilizer in the soil. Studies documented favorable effect of biofertilization on microbial Shannon, Chao and ACE diversity indices in the soil. It is concluded from intensive review of literature that all the three fertilization practices have their own way to benefit the soil with nutrients, but biofertilization provides long-term sustainability to crop lands. When it is used in integration with organic fertilizers, it makes the soil best for microbial growth and activity and increase microbial diversity, providing nutrients to soil for a longer time, thus improving crop productivity.


Asunto(s)
Microbiología del Suelo , Suelo , Agricultura , Fertilización , Fertilizantes/análisis , Humanos
12.
Sensors (Basel) ; 21(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204434

RESUMEN

The Internet of Things (IoT) and its benefits and challenges are the most emergent research topics among academics and practitioners. With supply chains (SCs) gaining rapid complexity, having high supply chain visibility (SCV) would help companies ease the processes and reduce complexity by improving inaccuracies. Extant literature has given attention to the organisation's capability to collect and evaluate information to balance between strategy and goals. The majority of studies focus on investigating IoT's impact on different areas such as sustainability, organisational structure, lean manufacturing, product development, and strategic management. However, research investigating the relationships and impact of IoT on SCV is minimal. This study closes this gap using a structured literature review to critically analyse existing literature to synthesise the use of IoT applications in SCs to gain visibility, and the SC. We found key IoT technologies that help SCs gain visibility, and seven benefits and three key challenges of these technologies. We also found the concept of Supply 4.0 that grasps the element of Industry 4.0 within the SC context. This paper contributes by combining IoT application synthesis, enablers, and challenges in SCV by highlighting key IoT technologies used in the SCs to gain visibility. Finally, the authors propose an empirical research agenda to address the identified gaps.


Asunto(s)
Internet de las Cosas , Confidencialidad , Tecnología
13.
J Pak Med Assoc ; 71(3): 943-949, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34057954

RESUMEN

Self-medication is the use of medicines by people on the basis of their own experience without consulting a doctor. People use medicines for pain management or to cure a disease and sometime this may be unnecessary. There are a lot of public and professional health concerns about misuse of medicines and globally physicians agree upon this rising issue that leads to antibiotic resistance. In developing countries, medicines without prescription are easily available which results in many adverse outcomes, especially bacterial resistance. Insufficient healthcare services and socioeconomic factors result in increased proportion of self-medication compared to drugs prescribed by physicians. The current narrative review was planned to focus on indicating prevalence rate of self-medication in different developed and under-developed countries, major risk factors and control of self-medication due to which antibiotic resistance rate can be minimised. The issue needs urgent attention of representative authorities for taking serious actions. Furthermore, arranging awareness seminars and implementing new policies/regulations to prevent the sale of any drug/antibiotic without prescription could play a vital role in bringing this alarming issue under control.


Asunto(s)
Salud Pública , Automedicación , Antibacterianos/efectos adversos , Farmacorresistencia Microbiana , Salud Global , Humanos
14.
Eur J Clin Microbiol Infect Dis ; 39(1): 85-92, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31482419

RESUMEN

In order to obtain more information on the MRSA population structure in the border region of Afghanistan and Pakistan, we collected and genotyped MRSA causing bloodstream infections from a tertiary care hospital in Peshawar, Pakistan, that serves the local population as well as Afghan immigrants and refugees. Thirty-one MRSA isolates from 30 patients were included and characterized by microarray hybridisation. For 25 patients, serum samples were tested using protein microarrays in order to detect antibodies against staphylococcal virulence factors. The most conspicuous result was the high rate of PVL-positive MRSA. Twenty-two isolates (71%) harboured lukF/S-PV genes. The most common lineage was CC772-MRSA-V/VT (PVL+) to which eleven isolates were assigned. The second most common strain was, surprisingly, CC8-MRSA-[IV+ACME] (PVL+), "USA300" (9 isolates). Two isolates were tst1 positive CC22-MRSA-IV, matching the Middle Eastern "Gaza Epidemic Strain". Another two were PVL-positive CC30-MRSA-IV. The remaining isolates belonged to, possibly locally emerging, CC1, CC5, and CC8 strains with SCC mec IV elements. Twenty-three patient sera were positive for anti-PVL-IgG antibodies. Several questions arise from the present study. It can be assumed that MRSA and high rates of PVL-positive S. aureus/MRSA are a public health issue in the Afghanistan/Pakistan border region. A possible emergence of the "USA300" clone as well as of the CC772 lineage warrants further investigation.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Staphylococcus aureus Resistente a Meticilina/clasificación , Sepsis/microbiología , Infecciones Estafilocócicas/sangre , Factores de Virulencia/inmunología , Adulto , Afganistán , Técnicas de Tipificación Bacteriana , Femenino , Genotipo , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Pakistán , Análisis por Matrices de Proteínas , Infecciones Estafilocócicas/microbiología , Factores de Virulencia/genética
15.
Sensors (Basel) ; 20(23)2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33261021

RESUMEN

The evolution of intelligent manufacturing has had a profound and lasting effect on the future of global manufacturing. Industry 4.0 based smart factories merge physical and cyber technologies, making the involved technologies more intricate and accurate; improving the performance, quality, controllability, management, and transparency of manufacturing processes in the era of the internet-of-things (IoT). Advanced low-cost sensor technologies are essential for gathering data and utilizing it for effective performance by manufacturing companies and supply chains. Different types of low power/low cost sensors allow for greatly expanded data collection on different devices across the manufacturing processes. While a lot of research has been carried out with a focus on analyzing the performance, processes, and implementation of smart factories, most firms still lack in-depth insight into the difference between traditional and smart factory systems, as well as the wide set of different sensor technologies associated with Industry 4.0. This paper identifies the different available sensor technologies of Industry 4.0, and identifies the differences between traditional and smart factories. In addition, this paper reviews existing research that has been done on the smart factory; and therefore provides a broad overview of the extant literature on smart factories, summarizes the variations between traditional and smart factories, outlines different types of sensors used in a smart factory, and creates an agenda for future research that encompasses the vigorous evolution of Industry 4.0 based smart factories.

16.
J Pak Med Assoc ; 70(11): 1979-1984, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33341844

RESUMEN

OBJECTIVE: To investigate the frequency rate and sensitivity pattern of extended-spectrum beta-lactamase and metallobeta- lactamase producing Pseudomonas aeruginosa isolated from major hospitals. METHODS: The cross-sectional study was conducted in the Microbiology section of the Pathology Department of Ayub Medical College, Abbottabad, Pakistan, from September 2017 to April 2018, and comprised clinical samples collected from different medical wards of major hospitals in the study area. For the selective growth of Pseudomonas aeruginosa, Cetrimide agar was used, and different antibiotics were evaluated for the sensitivity pattern following Kirby-Bauer diffusion method. Pseudomonas aeruginosa producing extended-spectrum beta lactamase and metallo-beta-lactamase were identified through double disk synergy test and imipenem ethylenediaminetetraacetic acid tests respectively. Patient's demographic and medical history was noted on a proforma. Data was analysed using SPSS 22.0. RESULTS: Of the 242 samples screened, 46 (19%) were positive for Pseudomonas aeruginosa. These samples were highly sensitive to levofloxacin, amikacin, imipenem, meropenem and ciprofloxacin (p<0.05). Of the positive cases, 11 (23.91%) were detected for extended-spectrum beta-lactamase production, while 3 (6.52%) samples were detected for metallo-beta-lactamase production. CONCLUSIONS: Pseudomonas aeruginosa samples were widely resistant to most antibiotics, but were sensitive for some antibiotics which may be recommended by physicians when treating Pseudomonas aeruginosa infection.


Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Estudios Transversales , Humanos , Pruebas de Sensibilidad Microbiana , Pakistán/epidemiología , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/epidemiología , beta-Lactamasas
17.
J Pak Med Assoc ; 70(7): 1199-1202, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32799273

RESUMEN

OBJECTIVE: To assess and compare the frequency of antibiotic-resistant staphylococcus aureus strains. METHODS: A retrospective study was conducted at the privately-owned Welfare Medical Laboratory, Peshawar, Pakistan, and comprised record related to the period between 07th February 2017 and 23rd March 2018 of patients referred for pus-testing from Khyber Teaching Hospital, Lady Reading Hospital and the Hayatabad Medical Complex. Pus samples were obtained from various parts of body with cotton swabs. The samples were cultured and the isolated staphylococcus aureus strains were analysed against selected antibiotics. The frequency of the isolated strains was tested and compared using Prism 7 software. RESULTS: Of the 6780 samples, staphylococcus aureus was found in 4315(63.64%). Wild-type staphylococcus aureus strains were 2133(31.46%), followed by 825(12.16%) methicillin resistant, 792(11.68%) vancomycin intermediate, and 565(8.33%) vancomycin-resistant staphylococcus aureus strains. The isolated strains were significant (p<0.0001) for operated wounds, and non-significant (p=0.8915) for diabetic foot cases. CONCLUSIONS: The frequency of antibiotic-resistant staphylococcu saureus strains was high.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana , Pakistán/epidemiología , Estudios Retrospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus
18.
Nanoscale ; 16(1): 262-272, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38054842

RESUMEN

Despite the prodigious potential of lithium-sulfur (Li-S) batteries as future rechargeable electrochemical systems, their commercial implementation is hindered by several vital issues, including the shuttle effect and sluggish migration of lithium-polysulfides leading to rapid capacity fading. Here, we systematically investigate the potential of first-row two-dimensional transition metal carbides (TMCs) as sulfur cathodes for Li-S batteries. The adsorption strength of lithium-polysulfides on TMCs is induced by the amount of charge transfer from the former to the latter and the proposed periodic relationship between sulfur in Li2S and 3d-transition metals. Our findings show that the VC nanosheet possesses immense anchoring potential and exhibits a comparatively low migration energy barrier for lithium-ion and Li2S molecules. Additionally, we report ab initio molecular dynamics simulations for lithiated polysulfide species anchored on a TMC-based model with a liquid-electrolyte medium. The microscopic reaction mechanism, revealed by the evolution of the reaction voltage during lithiation, demonstrates that the dissolution of high-order lithium-polysulfides in the electrolytes can be prevented due to their robust interaction with TMC-based cathode materials. These appealing features suggest that TMCs present colossal performance improvements for anchoring lithium-polysulfides, stimulating the active design of sulfur cathodes for practical Li-S batteries.

19.
Front Psychol ; 13: 877083, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36733868

RESUMEN

The purpose of the study is to investigate consumer wellbeing because of consumer participation, value co-creation, and customer resilience. This research identified the interaction effect of service climate in the presented context. The data were collected from 490 hotel customers. The structural equation modelling technique was used to observe the hypotheses testing. Participants of the study positively supported the impact of customer participation on customer wellbeing directly and indirectly. Moreover, results showed the partial mediation of customer resilience and value co-creation between customer participation and customer wellbeing. Service climates strengthen the relationship between customer participation and resilience and value co-creation. Theoretical and practical implications have also been added.

20.
RSC Adv ; 12(55): 35703-35711, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36545114

RESUMEN

Carbon dioxide foam injection is a promising enhanced oil recovery (EOR) method, being at the same time an efficient carbon storage technology. The strength of CO2 foam under reservoir conditions plays a crucial role in predicting the EOR and sequestration performance, yet, controlling the strength of the foam is challenging due to the complex physics of foams and their sensitivity to operational conditions and reservoir parameters. Data-driven approaches for complex fluids such as foams can be an alternative method to the time-consuming experimental and conventional modeling techniques, which often fail to accurately describe the effect of all important related parameters. In this study, machine learning (ML) models were constructed to predict the oil-free CO2 foam apparent viscosity in the bulk phase and sandstone formations. Based on previous experimental data on various operational and reservoir conditions, predictive models were developed by employing six ML algorithms. Among the applied algorithms, neural network algorithms provided the most precise predictions for bulk and porous media. The established models were then used to compute the critical foam quality under different conditions and determine the maximum apparent foam viscosity, effectively controlling CO2 mobility to co-optimize EOR and CO2 sequestration.

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