Geochemical Evaluation of Paleocene Source Rocks in the Kohat Sub-Basin, Pakistan.

The Kohat sub-basin is one of the main hydrocarbon-producing sedimentary basins located in the northwest extension of the Indus Basin in Pakistan. It contains numerous proven and potential petroleum from the Cambrian to the Miocene. Conventional petroleum resources have been depleting rapidly over the last couple of years. Therefore, unconventional resources should be explored using a variety of geochemical and geophysical techniques to address the energy demands. Geochemical techniques, including total organic carbon (TOC) assessment, Rock-Eval pyrolysis, organic petrography, and biomarker studies, are essential for evaluating the potential of shale gas reservoirs to delineate future prospects in a basin. The source rock potential of the Paleocene rocks, including the Patala, Lockhart, and Hangu formations of the sub-basin, is evaluated using geochemical analyses on well cuttings from the Tolanj-01 well. The analyses include estimation of total organic carbon (TOC), Rock-Eval pyrolysis, and organic petrography (vitrinite reflectance) to evaluate the organic richness, thermal maturity, kerogen type, hydrocarbon type, and environment of deposition. Other techniques for extractable organic matter (EOM) include solid-liquid chromatographic separation of fractions, gas chromatography (GC-FID)/whole oil chromatography, and gas chromatography-mass spectrometry (GC-MS). The organic matter (TOC, wt %) analysis reveals that 18 (18) samples of the Hangu formation (0.08-1.8 wt %) show poor values, 12 (12) samples of the Lockhart formation (0.05-0.5 wt %) have poor to fair content, and 26 (26) samples of the Patala formation have poor to fair (0.08-0.19 wt %) TOC content. Rock-Eval pyrolysis studies including hydrogen index, oxygen index, Tmax, quantities of free hydrocarbons (S1, mg/g), and hydrocarbons produced from pyrolysis (S2, mg/g) are determined for the well-cut samples (56) of the Paleocene rocks. The hydrogen index values for the Hangu formation are lower than 200, and those for the Lockhart and Patala formations range between 100 and 250. A maceral analysis is also conducted on these samples, which reveal that the majority of the samples of the Paleocene units present in the basin belong to kerogen types II/III. The thermal maturity of the Hangu and Lockhart formations falls in the late-stage oil window, while that of the Patala formation falls in the peak to late oil window. The genetic potential (GP) for these rock units is also determined based on S1 and S2 values, which reveals that it is generally poor except for a few samples of the Hangu and Lockhart formations, which show fair GP values. For the organic petrography (vitrinite reflectance, R0), one sample from each unit is selected, which shows that the Hangu, Lockhart, and Patala formations fall in the category of the mature oil window with their R0 (%) values being 0.95, 0.89, and 0.82, respectively. The extracts (EOM) from these rock units are also analyzed to assess the depositional settings, biological source input, biodegradation, thermal maturity, etc. The greater values of pristine to phytane (Pr/Ph > 1) ratios for Hangu (1.33), Lockhart (1.23), and Patala (1.8) indicate an intermediate condition (suboxic), while a cross-plot of Pr/n-C17-Ph/n-C18 shows that the organic matter is deposited in a transitional setting. The ratios between C19TCT/C19 TCT + C23 TCT and C24 TeCT/C24TeCT + C23TCT biological source inputs are mainly of marine origin. Similarly, the ternary diagram of regular steranes (C27-C28-C29) shows a greater marine input. Lower values of the carbon preference index (CPI1) for Hangu (0.95), Lockhart (0.91), and Patala (1.04) indicate higher thermal maturity of the Paleocene rocks. Similarly, the methylphenanthrene index (MPI-1) values, Moretane index, and Pr/n-C17 vs Ph/n-C18 plots also show higher thermal maturity for these rock extracts.

Advances on concrete strength properties after adding polypropylene fibers from health personal protective equipment (PPE) of COVID-19: Implication on waste management and sustainable environment.

Using Health personal protective equipment (PPE) such as face masks, safety foot shoes and protective suits has expanded dramatically due to COVID-19 pandemic leading to a widespread distribution of the PPE, particularly the face masks, in the environments including streets, dump sites, seashores and other risky locations. The environmental degradation of polypropylene, the essential plastic component in single-use face masks (SUM), takes between 20 and 30 years and thus it is essential to develop experimental approaches to recycle the polypropylene or to reuse it in different ways. This paper explores the integration of SUM into concrete structures to improve its mechanical properties. We first to cut the inner nose wire and ear loops, then distribute the PPE material among five different mixed styles. The PPE were applied by volume at 0%, 1%, 1.5%, 2.0%, and 2.5%, with tests focusing on UCS, STS, FS, and PV to determine the concrete's overall consistency and assess the improvement in its mechanical properties. The results showed that adding PPE improves the strength properties and general performance of the concrete specimens. The pattern of rising intensity started to fade after 2%. The findings demonstrated that adding PPE fibers enhanced the UCS by 9.4% at the optimum 2% PPE. The PPE fibers, on the other side, are crucial in calculating the STS and FS of the reinforcement concrete.

Early γ-irradiation and subsequent storage of red cells in SAG-M additive solution potentiate energy imbalance, microvesiculation and susceptibility to stress-induced apoptotic cell death.

γ-Irradiation of red blood cell (RBC) concentrates prevents transfusion-associated graft-versus-host disease but may diminish RBC quality. Herein, we show that early γ-irradiation (25 Gy) of RBC units and their subsequent storage in SAG-M additive solution altered membrane microvesiculation, supernatant haemoglobin and cytosolic ATP. γ-Irradiation did not influence phosphatidylserine externalization, a marker of erythrocyte apoptotic cell death (eryptosis), in RBC stored for 42 days. However, shorter periods (4-21 days) of storage accentuated eryptosis in γ-irradiated RBC versus untreated RBCs following energy depletion, suggesting that γ-irradiated RBC is primed for stress-induced eryptosis during storage.

Silkworm nucleotide databases--current trends and future prospects.

The domesticated silkworm, Bombyx mori serves as an ideal representative of lepidopteran species for a variety of scientific studies. As a result, databases have been created to organize information pertaining to the silkworm genome that is subject to constant updating. Of these, four main databases are important for store nucleotide information in the form of genomic data, ESTs and microsatelites. These databases also store data related to other lepidoptera and important insects, which help in insect biological research. Though a considerable amount of nucleotide data is currently available, there is a paucity of data related to silkworm and other lepidopteran proteins. Hence, the focus of this article is to present the current status of nucleotide databases of silkworm, avenues for improvement and possibilities for databases that could be created in the future.

Sinusoidal magnetic fields and chawki (silkworm) rearing in sericulture.

Effects of sinusoidal magnetic fields on chawki silkworm rearing have been studied. The experiment was conducted using a multi X Bi silkworm hybrid, PM x CSR 2. Disease-free layings were reared from hatching to cocooning and by subjecting first and second instar to three magnetic field frequencies: 0.1, 1.0, and 10 Hz at 1500 nT, pp, for six days at six hours per day. Controls were maintained simultaneously. Larval durations for both young-stage chawki (I and II) and late stage (III, IV, V) were calculated in days and hours, including the feeding and moulting periods for I to IV instars, and the feeding period for V instar up to the time of spinning. The study revealed that the magnetic exposures reduced both feeding and moulting times with no adverse effects on larval growth. The substantial reductions in time, 33 hours in instars I and II, and 64 hours in total larval duration, could be commercially important in chawki rearing, saving time, leaf consumption, and labor expenses.

MR imaging of giant intracranial aneurysm.

We reviewed the clinical features and findings of magnetic resonance imaging (MRI) in 17 cases of giant intracranial aneurysm (GIA). All were confirmed by digital subtraction angiography (DSA). Seven were non-thrombosed and 10 were partially thrombosed.All thrombosed parts showed no enhancement. The majority of the lumen showed good enhancement in the post-contrast study (89%). About 80% of the partially thrombosed aneurysms had an onion skin appearance on non-contrast T1WI. On T2WI about 80% of partially thrombosed aneurysms had a low signal inside the thrombus or its wall from the susceptibility effect of blood elements such as haemosiderin. Flow void sign was noted in 88% on non-contrast T1WI and T2WI. Flow artifacts along the phase-encoding direction from the lumen of the aneurysm were noted in 41% of non-contrast T1WI, 56% of contrast-enhanced T1WI, and 29% of T2WI.Non-enhancement inside the thrombus and an onion skin appearance were important signs of thrombosis of the aneurysm. Flow artifacts along the phase-encoding direction from the lumen of the aneurysm provided an important clue of a patent lumen inside an aneurysm. The following signs provided clues to the diagnosis of patency lumen instead of thrombosis with high sensitivity and specificity: flow void sign on noncontrast T1WI (sensitivity 88%, specificity 100%), enhancement on contrast-enhanced T1WI (sensitivity 89%, specificity 100%), presence of either flow void sign or enhancement on contrast-enhanced T1WI (sensitivity 100%, specificity 100%).

Antimicrobial susceptibility testing and patterns of resistance at a tertiary care center.

Clinical microbiology laboratories are faced with the challenge of accurately detecting emerging antibiotic resistance in bacterial pathogens. In recent years, vancomycin resistant enterococci have emerged, as have penicillin resistant pneumococci and more recently, methicillin-resistant Staphylococcus aureus with reduced susceptibility to vancomycin. In order to detect these emerging resistant pathogens it is essential that antimicrobial susceptibility be carried out by laboratories as an integral part of therapeutic strategies. In this review, we discuss patterns of susceptibility of different antimicrobials as experienced at King Faisal Specialist Hospital and Research Centre, a tertiary care center in Riyadh.

Current status and changing trends of antimicrobial resistance in Saudi Arabia.

Due to modern travel and ease of spread of infections, it is desirable to widen knowledge of susceptibility of common bacterial isolates from different parts of the world for optimal clinical management and control programs. Over the past decades, antimicrobial resistance has emerged in all kinds of micro-organisms worldwide including Saudi Arabia. This phenomenon is primarily due to increasing antibiotic use and misuse in humans, animals and agriculture. Additionally, the presence of a large expatriate population and a significant number of visitors to the Kingdom annually for pilgrimage and/or work from all over the world may have also facilitated the importation to Saudi Arabia of drug resistant micro-organisms from other countries. Saudi Arabia has witnessed an increase of drug resistant Mycobacterium tuberculosis, Streptococcus pneumoniae, Staphylococcus aureus and some Enterobacteriaceae in the last decade. We describe the status of antimicrobial resistance in Saudi Arabia which is an important focus of antimicrobial resistance for the Gulf Region.

Cutaneous myiasis due to Dermatobia hominis in Saudis.

Cutaneous myiasis infestations are normally found in South and Central America but increasing travel has resulted in their spread to non-indigenous countries with increasing frequency. We report two cases of cutaneous infestation by Dermatobia hominis in Taif, Saudi Arabia. There was no history of travel outside Saudi Arabia. The source of infection appears to be domestic cattle indicating that these infestations may be endemic in this region.

Influenza viruses in children attending major referral center in Saudi Arabia.

Full text is available as a scanned copy of the original print version.

Influenza viruses in children attending major referral center in Saudi Arabia.

Full text is available as a scanned copy of the original print version.

Enterohemorrhagic Escherichia coli. A dangerous food-borne pathogen.

Since 1982, several outbreaks of hemorrhagic colitis due to EHEC, or E coli O157:H7, have occurred in the United States and other parts of the world. Contaminated, undercooked ground beef has been most frequently implicated in the outbreaks, although unpasteurized dairy products and other foods have also been the source of infection in sporadic cases. The most common clinical manifestation of EHEC infection is abdominal cramps and watery, bloody diarrhea. HUS secondary to the initial colitis develops in about 10% of patients under 10 years of age. Definitive diagnosis is made by isolation and identification of EHEC in stool samples. Treatment focuses on rehydration and supportive therapy. The use of antimicrobial agents, narcotics, or antimotility agents is not recommended, because they neither shorten the course of illness nor prevent the development of sequelae.

Respiratory viruses in children attending a major referral centre in Saudi Arabia.

Viral respiratory infections are common causes of illness in infants and children. Examination of clinical specimens submitted for diagnosis during a 3-year period (August 1993-July 1996) at King Faisal Specialist Hospital and Research Center (KFSH & RC) in Riyadh revealed a wide spectrum of diseases associated with the isolation of five respiratory viruses. Severity of disease ranged from mild upper respiratory illness to threatening lower respiratory illnesses including bronchiolitis and pneumonia. Of the 256 isolates, respiratory syncytial virus (RSV) accounted for 73 (28.5%), adenoviruses for 70 (27.3%), influenza viruses for 61 (23.8%), enteroviruses for 39 (15.2%) and para-influenza for 13 (2.3%). Viruses were found more frequently in children attending emergency or paediatric wards than in outpatients. RSV appears in November and the seasonal peak occurs during January and February. Influenza activity begins in September and peaks in November and December. Para-influenza type I emerges in winter and para-influenza type III follows the influenza epidemic and may be detected sporadically in summer. The other viruses (enteroviruses, adenoviruses) were isolated throughout the year.

In vitro induction of tetraploidy in mulberry (Morus alba L.).

A high frequency of tetraploidy was induced in mulberry (Morus alba L.) through apical bud treatment under in vitro conditions. Apical buds from in vitro-grown plants were treated with three different concentrations (0.05, 0.1 and 0.2%) of colchicine in MS medium for 24 h. Tetraploidy at a frequency of 39.4±4.8% was obtained using 0.1% colchicine, whereas the frequency of tetraploidy was significantly reduced to 16.7±2.3% when 0.2% colchicine was used. Morphological, histological and cytological evidence indicated a phenotypic and genomic similarity of in vitro- with ex vitro-induced tetraploids. Rooting of tetraploids was on basal medium containing 2.6 µM NAA. The recovery of tetraploids was 80.8% more efficient using the in vitro method instead of the ex vitro method. The use of the same colchicine medium for up to 4 weeks with additional explants was found to be equally effective for the induction of tetraploidy.

Antibacterial activity of trovafloxacin against nosocomial Gram-positive and Gram-negative isolates.

A total of 1132 clinical isolates from 952 patients with nosocomial infections were tested against the fluoroquinolone trovafloxacin by the agar dilution method. They comprised 285 staphylococci, 111 streptococci, 94 enterococci and 470 isolates of Enterobacteriaceae, 92 Pseudomonas aeruginosa, 27 Stenotrophomonas maltophilia, 28 Haemophilus influenzae and 25 Acinetobacter calcoaceticus. The in-vitro activity of trovafloxacin was compared with that of ciprofloxacin, norfloxacin, beta-lactam and aminoglycoside agents. Over 96% of Enterobacteriaceae were susceptible to trovafloxacin with an MIC of <0.03-4 mg/L. It also inhibited 97% and 100% clinical isolates of P. aeruginosa and S. maltophilia, respectively. All staphylococci, including 51 strains of methicillin-resistant Staphylococcus aureus, were susceptible to trovafloxacin, which also had excellent activity against streptococci and enterococci, inhibiting all 111 strains of the former and 94% of the latter. Trovafloxacin had a greater activity against both Gram-positive and Gram-negative bacteria than ciprofloxacin, norfloxacin, penicillins, cephalosporins and the aminoglycosides tested.

In vitro activity of quinupristin/dalfopristin, RP59500, against gram-positive clinical isolates.

Synercid (quinupristin/dalfopristin, RP59500) is a new water-soluble streptogramin which offers some advantages over the commercially available antimicrobials against drug-resistant gram-positive bacteria. Its in vitro activity was compared with ampicillin, augmentin, penicillin, erythromycin, oxacillin and vancomycin against gram-positive bacteria isolated from clinical specimens. Of the 837 gram-positive bacteria tested 834 (99.6%) were inhibited by < 0.6-4.0 mg/l of Synercid. It had excellent activity against both staphylococci and streptococci, including methicillin-resistant staphylococci and vancomycin-resistant enterococci.

Genetic homogeneity among methicillin-resistant Staphylococcus aureus strains from Saudi Arabia.

Ninety-four strains of methicillin-resistant Staphylococcus aureus (MRSA) were collected from patients nursed in several hospitals in Saudi Arabia, before they were referred to King Faisal Specialist Hospital and Research Centre for tertiary care. The hospitals were from geographically diverse regions and as such the entirety of Saudi Arabia was covered. All strains were genetically typed by random amplification of polymorphic DNA (RAPD) analysis using three different primers and a representative subset of the strains was analyzed with pulsed-field gel electrophoresis (PFGE) as well. It was concluded that 87 out of 94 (93%) belong to a single clonally related lineage of MRSA. In the other 7 cases, the DNA banding patterns were shown to differ only slightly from those determined for the clonal type. PFGE analysis confirmed the homogeneity of the collection of strains. When the RAPD and PFGE fingerprints obtained for the Saudi clone were compared to those generated for a collection of MRSA with a more diverse geographical background, it was shown that the clonal type from Saudi Arabia was not identical to any of these MRSA strains. Our data provide another example of the capacity of certain MRSA clones to expand through entire nations and establish themselves permanently among large number of hospitals and, consequently, even larger numbers of patients.

Enteroviruses at a tertiary care center in Saudi Arabia, 1989-1995.

Enteroviruses (EVs) are among the most common viral pathogens affecting humans. Enterovirus (EV) infections occur worldwide in temperate climates with a marked summer/fall season and have a high year-round incidence in tropical and subtropical areas. In Saudi Arabia, the epidemiology of enteroviruses is unknown. Of the clinical specimens submitted for diagnosis during a six-year period (1989-1995) at King Faisal Specialist Hospital and Research Centre (KFSH&RC) in Riyadh, a wide variety of diseases were associated with the isolation of enteroviruses. Among the diseases were herpangina, sepsis-like illness, hand-foot-and-mouth syndrome, laryngotracheitis (croup), aseptic meningitis, pneumonia, and gastrointestinal illness. During the six-year study, a variety of enteroviruses were isolated. Although epidemics were seen in mid-winter and early spring, EV which may cause sporadic diseases were isolated in each of the 12 months. Health care providers must become aware of the epidemic potential not only in mid-winter and early spring, but also throughout the year, as this will aid in the diagnosis and management of this illness.