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Incorporating heteroatoms into graphene lattice results in enhanced electrical conductivity and electrochemically active sites and has significant importance in developing high-performance supercapacitors. In this study, sulfur and nitrogen co-doped graphene aerogel is synthesized via hydrothermal technique followed by a simple but effective freeze-thawing and ambient pressure drying process (referred to as SN-GA). The process requires low-cost raw materials and cost-effective equipment without the utilization of any special instrument that operates at ultra-low temperatures, under high pressure, or vacuum environment. Ammonium sulfate [(NH4)2SO4] and ethylenediamine are used as a source of sulfur and nitrogen and as a reducing agent. (NH4)2SO4 with different molarities (0, 12, 24, and 36 mM) are used to synthesize four different aerogel samples marked as GA, SN-GA1, SN-GA2, and SN-GA3. The electrode is prepared using an SN-GA2 sample, exhibiting an outstanding specific capacitance of 244 F g−1 at an applied current density of 1 A g−1 with almost 98.5% Coulomb efficiency. Furthermore, based on the SN-GA2 sample, the symmetrical supercapacitor is fabricated, displaying an energy density of 18.14 Wh kg−1 at a power density of 498.4 W kg−1. Hence, SN-GA2 renders a promising material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Purpose: To determine frequency of "diabetic retinopathy (DR)" in patients admitted at a tertiary care hospital with diabetic foot. Study Design: Cross sectional study. Place and Duration of Study: HBS medical and dental college, Islamabad from November 2022 to November 2023. Methods: Sixty two patients admitted with "diabetic foot ulcer" (DFU) were included in this study. Severity of DFU was assessed using. Patients were assessed for presence of "diabetic retinopathy (DR)" as well as its severity. Data was analyzed using SPSS 22. Results: Mean age was 49.37 ± 11.02 years. There were 34 (54.84%) males and 28 (45.16%) females. Mean HbA1C% was 9.46 ± 1.11%. Mean duration of diabetes was 10.06 ± 5.53 years. Forty five percent patients had diabetic retinopathy (DR). Amongst these patients diagnosed with DR (n = 45), 6 (13.33%) had mild non-proliferative DR, 20 (44.44%) had moderate non-proliferative DR, 14 (31.11%) had severe non-proliferative DR and 5 (11.11%) had proliferative DR. According to Wagner Grade there were 32 (51.61%), patients with grade 2 DFU, 19 (30.65%) had grade 1 and 11 (17.74%) had grade 3. Coexistence of diabetic retinopathy and diabetic foot in patients admitted at indoor facility was 72.58%. Conclusion: Prevalence of "diabetic retinopathy (DR)" in patients admitted with diabetic foot was 72.58%. Presence of diabetic foot can be considered as strong predictor of presence of concomitant "diabetic retinopathy". [ABSTRACT FROM AUTHOR]

Objective: To determine patient satisfaction with successful external dacryocystorhinostomy for one eye and patients' preference time for second eye dacryocystorhinostomy after the first surgery. Study Design: Prospective longitudinal study. Place and Duration of Study: Department of Ophthalmology, HBS General Hospital, Islamabad Pakistan, from Jan 2018 to Dec 2020. Methodology: A sample of 37 patients was calculated. All selected patients underwent bilateral external dacryocystorhinostomy and were followed for six months. Patient satisfaction was measured using a treatment satisfaction scale. Results: A total of 37 patients were included in the study. The mean age of patients was 33.5 ± 3.1 years. Satisfaction with 1st eye external DCR was extremely satisfied in 14 (37.8%), satisfied in 14 (37.8%), neutral in 2 (5.4%), dissatisfied in 6 (16.2%) and extremely dissatisfied 1 (2.6%). 31 (83.8%) prefer second eye surgery in =1 year after first eye DCR, while 6 (16.2%) prefer second eye surgery after more than one year of first eye DCR surgery. The majority of females prefer =1 year duration for second eye DCR surgery as compared to males 25 (67.7%) vs 6 (16.2%), (p=0.03). Anatomical success and functional success were insignificantly associated with satisfaction of first eye DCR surgery of patients (p=0.793 and p=0.482) Conclusions: High satisfaction with first eye dacryocystorhinostomy and greater preference for second eye dacryocystorhinostomy was found in patients coming to tertiary care hospital in Pakistan. [ABSTRACT FROM AUTHOR]

Temperature is a critical parameter in machining as it directly affects the cutting performance, part quality, residual stresses, distortion, tool life, etc. In this article, a novel analytical algorithm for fast temperature prediction in intermittent cutting processes like milling is proposed. For the first time, the temperature drop during the noncutting period is taken into consideration for the workpiece side. The model also takes into account time-varying chip thickness due to the trochoidal motion of the milling tool. Validation tests with Ti6Al4V showed the promise of the algorithm in predicting the milling temperature under various cutting conditions. [ABSTRACT FROM AUTHOR]

Abstract TATA binding protein (TBP) is a key component of the eukaryotic transcription initiation machinery. It functions in several complexes involved in core promoter recognition and assembly of the pre-initiation complex. Through gene duplication eukaryotes have expanded their repertoire of TATA binding proteins, leading to a variable composition of the transcription machinery. In vertebrates this repertoire consists of TBP, TBP-like factor (TLF, also known as TBPL1, TRF2) and TBP2 (also known as TBPL2, TRF3). All three factors are essential, with TLF and TBP2 playing important roles in development and differentiation, in particular gametogenesis and early embryonic development, whereas TBP dominates somatic cell transcription. TBP-related factors may compete for promoters when co-expressed, but also show preferential interactions with subsets of promoters. Initiation factor switching occurs on account of differential expression of these proteins in gametes, embryos and somatic cells. Paralogs of TFIIA and TAF subunits account for additional variation in the transcription initiation complex. This variation in core promoter recognition accommodates the expanded regulatory capacity and specificity required for germ cells and embryonic development in higher eukaryotes.

Abstract Background TATA-box-binding protein 2 (TBP2/TRF3) is a vertebrate-specific paralog of TBP that shares with TBP a highly conserved carboxy-terminal domain and the ability to bind the TATA box. TBP2 is highly expressed in oocytes whereas TBP is more abundant in embryos. Results We find that TBP2 is proteolytically degraded upon meiotic maturation; after germinal vesicle breakdown relatively low levels of TBP2 expression persist. Furthermore, TBP2 localizes to the transcriptionally active loops of lampbrush chromosomes and is recruited to a number of injected promoters in oocyte nuclei. Using an altered binding specificity mutant reporter system we show that TBP2 promotes RNA polymerase II transcription in vivo. Intriguingly, TBP, which in oocytes is undetectable at the protein level, can functionally replace TBP2 when ectopically expressed in oocytes, showing that switching of initiation factors can be driven by changes in their expression. Proteolytic degradation of TBP2 is not required for repression of transcription during meiotic maturation, suggesting a redundant role in this repression or a role in initiation factor switching between oocytes and embryos. Conclusion The expression and transcriptional activity of TBP2 in oocytes show that TBP2 is the predominant initiation factor in oocytes, which is substituted by TBP on a subset of promoters in embryos as a result of proteolytic degradation of TBP2 during meiotic maturation.

In the modern era companies seek the use of modern technologies in order to upgrade their infrastructure and enhance their business growth. The use of business intelligence, data science and cloud computing (CC) has become an integral part of business. Different factors play important role in the adoption of cloud services. An organization willing to adopt cloud services should consider them. This paper explores the factors and addresses the issues in implementing and deploying CC in telecom companies. In addition, this study also shares the benefits of utilizing CC which is a novel technical pattern which can change the use of different associations of information technology as a service. CC concentrates on the idea of definition, security problems, service models and infrastructures of its development. The important point is to analyze how this paradigm should be adopted in telecom industries and its results. This research study presents a comparative analysis of adaptation of CC by various telecom industries. The results identify certain limitations which also play their role for adaptation of CC in telecom companies. [ABSTRACT FROM AUTHOR]

Since the discovery of induced pluripotent stem cells there has been intense interest in understanding the mechanisms that allow a somatic cell to be reprogrammed back to a pluripotent state. Several groups have studied the alterations in gene expression that occur as somatic cells modify their genome to that of an embryonic stem cell. Underpinning many of the gene expression changes are modifications to the epigenetic profile of the associated chromatin. We have used a large-scale shRNA screen to identify epigenetic modifiers that act as barriers to reprogramming. We have uncovered an important role for TRIM28 in cells resisting transition between somatic and pluripotent states. TRIM28 achieves this by maintaining the H3K9me3 repressed state and keeping endogenous retroviruses (ERVs) silenced. We propose that knockdown of TRIM28 during reprogramming results in more plastic H3K9me3 domains, dysregulation of genes nearby H3K9me3 marks, and up regulation of ERVs, thus facilitating the transition through reprogramming. S tem C ells 2017;35:147-157 [ABSTRACT FROM AUTHOR]

Background: Chromatin proteins control gene activity in a concerted manner. We developed a high-throughput assay to study the effects of the local chromatin environment on the regulatory activity of a protein of interest. The assay combines a previously reported multiplexing strategy based on barcoded randomly integrated reporters with Gal4-mediated tethering. We applied the assay to Drosophila heterochromatin protein 1a (HP1a), which is mostly known as a repressive protein but has also been linked to transcriptional activation. Results: Recruitment to over 1000 genomic locations revealed that HP1a is a potent repressor able to silence even highly expressing reporter genes. However, the local chromatin context can modulate HP1a function. In pericentromeric regions, HP1a-induced repression was enhanced by twofold. In regions marked by a H3K36me3-rich chromatin signature, HP1a-dependent silencing was significantly decreased. We found no evidence for an activating function of HP1a in our experimental system. Furthermore, we did not observe stable transmission of repression over mitotic divisions after loss of targeted HP1a. Conclusions: The multiplexed tethered reporter assay should be applicable to a large number of chromatin proteins and will be a useful tool to dissect combinatorial regulatory interactions in chromatin. [ABSTRACT FROM AUTHOR]

Control of surface integrity is a vital consideration in the machining of components subjected to fatigue loading, for example, critical components of aerospace engines. In this research, three important aspects of surface integrity of a machined part—surface roughness, micro-hardness, and residual stresses—were analyzed for their variations with the cutting parameters. Finish milling of super alloy GH4169/Inconel 718 was carried out using coated cemented carbide and whisker-reinforced coated ceramic inserts. All of the three machining parameters—cutting speed, feed rate, and depth of cut—were found to have a substantial effect on the surface integrity of the finished part. Although different cutting parameters gave different effects for the two types of cutting inserts, overall better surface integrity was obtained at minimum cutting feed and medium cutting speed and depth of cut value. Moreover, carbide inserts produced better surface integrity of the finished part, whereas ceramic inserts generated very high surface tensile stresses and poor surface finish due to back striking of the adhered metal chips. [ABSTRACT FROM PUBLISHER]

Summary EZH2 is frequently overexpressed in glioblastoma (GBM), suggesting an oncogenic function that could be a target for therapeutic intervention. However, reduced EZH2 activity can also promote tumorigenesis, leading to concerns about the use of EZH2 inhibitors. Here, we provide further insight about the effects of prolonged Ezh2 inhibition in glioblastoma using preclinical mouse models and primary tumor-derived human GBM cell lines. Using doxycycline-inducible shRNAs that mimic the effects of a selective EZH2 inhibitor, we demonstrate that prolonged Ezh2 depletion causes a robust switch in cell fate, including significantly enhanced proliferation, DNA damage repair, and activation of part of the pluripotency network, resulting in altered tumor cell identity and tumor progression. Short-term Ezh2 depletion significantly improved survival without the tumor progression observed upon prolonged Ezh2 depletion, suggesting that precise dosing regiments are very important. These results could be of high clinical relevance with regard to how glioblastomas should be treated with epigenetic therapies. [ABSTRACT FROM AUTHOR]

Retroviruses and DNA transposons are an important part of molecular biologists' toolbox. The applications of these elements range from functional genomics to oncogene discovery and gene therapy. However, these elements do not integrate uniformly across the genome, which is an important limitation to their use. A number of genetic and epigenetic factors have been shown to shape the integration preference of these elements. Insight into integration bias can significantly enhance the analysis and interpretation of results obtained using these elements. For three different applications, we outline how bias can affect results, and can potentially be addressed. [ABSTRACT FROM PUBLISHER]

The ability of retroviruses and transposons to insert their genetic material into host DNA makes them widely used tools in molecular biology, cancer research and gene therapy. However, these systems have biases that may strongly affect research outcomes. To address this issue, we generated very large datasets consisting of to unselected integrations in the mouse genome for the Sleeping Beauty (SB) and piggyBac (PB) transposons, and the Mouse Mammary Tumor Virus (MMTV). We analyzed (epi)genomic features to generate bias maps at both local and genome-wide scales. MMTV showed a remarkably uniform distribution of integrations across the genome. More distinct preferences were observed for the two transposons, with PB showing remarkable resemblance to bias profiles of the Murine Leukemia Virus. Furthermore, we present a model where target site selection is directed at multiple scales. At a large scale, target site selection is similar across systems, and defined by domain-oriented features, namely expression of proximal genes, proximity to CpG islands and to genic features, chromatin compaction and replication timing. Notable differences between the systems are mainly observed at smaller scales, and are directed by a diverse range of features. To study the effect of these biases on integration sites occupied under selective pressure, we turned to insertional mutagenesis (IM) screens. In IM screens, putative cancer genes are identified by finding frequently targeted genomic regions, or Common Integration Sites (CISs). Within three recently completed IM screens, we identified 7%–33% putative false positive CISs, which are likely not the result of the oncogenic selection process. Moreover, results indicate that PB, compared to SB, is more suited to tag oncogenes. [ABSTRACT FROM AUTHOR]

Summary: Reporter genes integrated into the genome are a powerful tool to reveal effects of regulatory elements and local chromatin context on gene expression. However, so far such reporter assays have been of low throughput. Here, we describe a multiplexing approach for the parallel monitoring of transcriptional activity of thousands of randomly integrated reporters. More than 27,000 distinct reporter integrations in mouse embryonic stem cells, obtained with two different promoters, show ∼1,000-fold variation in expression levels. Data analysis indicates that lamina-associated domains act as attenuators of transcription, likely by reducing access of transcription factors to binding sites. Furthermore, chromatin compaction is predictive of reporter activity. We also found evidence for crosstalk between neighboring genes and estimate that enhancers can influence gene expression on average over ∼20 kb. The multiplexed reporter assay is highly flexible in design and can be modified to query a wide range of aspects of gene regulation. [ABSTRACT FROM AUTHOR]

Cancer develops through a multistep process in which normal cells progress to malignant tumors via the evolution of their genomes as a result of the acquisition of mutations in cancer driver genes. The number, identity and mode of action of cancer driver genes, and how they contribute to tumor evolution is largely unknown. This study deployed the Mouse Mammary Tumor Virus (MMTV) as an insertional mutagen to find both the driver genes and the networks in which they function. Using deep insertion site sequencing we identified around 31000 retroviral integration sites in 604 MMTV-induced mammary tumors from mice with mammary gland-specific deletion of Trp53, Pten heterozygous knockout mice, or wildtype strains. We identified 18 known common integration sites (CISs) and 12 previously unknown CISs marking new candidate cancer genes. Members of the Wnt, Fgf, Fgfr, Rspo and Pdgfr gene families were commonly mutated in a mutually exclusive fashion. The sequence data we generated yielded also information on the clonality of insertions in individual tumors, allowing us to develop a data-driven model of MMTV-induced tumor development. Insertional mutations near Wnt and Fgf genes mark the earliest “initiating” events in MMTV induced tumorigenesis, whereas Fgfr genes are targeted later during tumor progression. Our data shows that insertional mutagenesis can be used to discover the mutational networks, the timing of mutations, and the genes that initiate and drive tumor evolution. [ABSTRACT FROM AUTHOR]

We report on a pulsed electron paramagnetic resonance (EPR) study of the photoexcited triplet state (S = 1) of oxygen-vacancy centers in silicon. Rabi oscillations between the triplet sublevels are observed using coherent manipulation with a resonant microwave pulse. The Hahn echo and stimulated echo decay profiles are superimposed with strong modulations known as electron-spin-echo envelope modulation (ESEEM). The ESEEM spectra reveal a weak but anisotropic hyperfine coupling between the triplet electron spin and a 29Si nuclear spin (I = 1/2) residing at a nearby lattice site, that cannot be resolved in conventional field-swept EPR spectra. [ABSTRACT FROM AUTHOR]

Pulsed electron paramagnetic resonance spectroscopy of the photoexcited, metastable triplet state of the oxygen-vacancy center in silicon reveals that the lifetime of the ms = ± 1 véis differs significantly from that of the ms = 0 state. We exploit this significant difference in decay rates to the ground singlet state to achieve nearly ∼100% electron-spin polarization within the triplet. We further demonstrate the transfer of a coherent state of the triplet electron spin to, and from, a hyperfine-coupled, nearest-neighbor 29 Si nuclear spin. We measure the coherence time of the 29Si nuclear spin employed in this operation and find it to be unaffected by the presence of the triplet electron spin and equal to the bulk value measured by nuclear magnetic resonance. [ABSTRACT FROM AUTHOR]

Transcription initiation involves the recruitment of basal transcription factors to the core promoter. A variety of core promoter elements exists; however for most of these motifs, the distribution across species is unknown. Here we report on the comparison of human and amphibian promoter sequences. We have used oligo-capping in combination with deep sequencing to determine transcription start sites in Xenopus tropicalis. To systematically predict regulatory elements, we have developed a de novo motif finding pipeline using an ensemble of computational tools. A comprehensive comparison of human and amphibian promoter sequences revealed both similarities and differences in core promoter architecture. Some of the differences stem from a highly divergent nucleotide composition of Xenopus and human promoters. Whereas the distribution of some core promoter motifs is conserved independently of species-specific nucleotide bias, the frequency of another class of motifs correlates with the single nucleotide frequencies. This class includes the well-known TATA box and SP1 motifs, which are more abundant in Xenopus and human promoters, respectively. While these motifs are enriched above the local nucleotide background in both organisms, their frequency varies in step with this background. These differences are likely adaptive as these motifs can recruit TFIID to either CpG island or sharply initiating promoters. Our results highlight both the conserved and diverged aspects of vertebrate transcription, most notably showing co-opted motif usage to recruit the transcriptional machinery to promoters with diverging nucleotide composition. This shows how sweeping changes in nucleotide composition are compatible with highly conserved mechanisms of transcription initiation. [ABSTRACT FROM AUTHOR]

The linewidth of the low-field electrically detected magnetic resonance (LFEDMR) of phosphorus electrons in silicon is investigated using samples with various 29Si nuclear spin fractions and is compared to that of X-band electron paramagnetic resonance (EPR). The linewidths of LFEDMR and EPR are the same even though LFEDMR signals are obtained based on spin-dependent recombination, suggesting that the interaction between electron spins of phosphorus and recombination centers is strong enough for the LFEDMR detection but weak enough not to affect the linewidths. This favorable balance makes LFEDMR an attractive method to elucidate the low-field behavior of paramagnetic defects in semiconductors. [ABSTRACT FROM AUTHOR]

A study was carried out recently to determine the pollution level ofwaters in the Karachi harbour and adjoining backwaters. Nine locations were selected, four in the backwaters, two on the seaside, and three in the main navigable channel. Four of these locations were deliberately selected to coincide with those of a previous study conducted in 1982 by Pakistan Council of Scientific and Industrial Research (PCSIR) so that the values for the concentration of different pollutantscould be compared. Analysis was conducted for pH, bicarbonates, Total Solids, Volatile matter in Total Solids, Chlorides, Sulphates, Calcium, Magnesium, Sodium and Potassium. The results indicate that the composition of sea water as far as the concentration of above constituents is concerned has not changed much since the time of the PCSIR study, viz 1982, except that the organic matter concentration has increased. The reasons for this increase in organic loading and its possible impact are discussed in this paper. [ABSTRACT FROM AUTHOR]

Enhancers are regulatory elements that promote gene expression in a spatio-temporal way and are involved in a wide range of developmental and disease processes. Both the identification and subsequent functional dissection of enhancers are key steps in understanding these processes. Several high-throughput approaches were recently developed for these purposes; however, in almost all cases enhancers are being tested outside their native chromatin context. Until recently, the analysis of enhancer activities at their native genomic locations was low throughput, laborious and time-consuming. Here, we discuss the potential of a powerful approach, TRIP, to study the functioning of enhancers in their native chromatin environments by introducing sensor constructs directly in the genome. TRIP allows for simultaneously analyzing the quantitative readout of numerous sensor constructs integrated at random locations in the genome. The high-throughput and flexible nature of TRIP opens up potential to study different aspects of enhancer biology at an unprecedented level. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ultrasonication homogenization was used for the nanoemulsion preparation. [•] Homogenization and formulation parameters were optimized using single factor method. [•] Nanoemulsions were stabilized by commercial modified starches with increased loading of bioactive compound. [•] Newly developed commercial modified starch performed better than conventionally used starches. [•] Ultrasonic homogenization process was easy to control and manipulate. [Copyright &y& Elsevier]

Summary The RNA-guided DNA endonuclease Cas9 is a powerful tool for genome editing. Little is known about the kinetics and fidelity of the double-strand break (DSB) repair process that follows a Cas9 cutting event in living cells. Here, we developed a strategy to measure the kinetics of DSB repair for single loci in human cells. Quantitative modeling of repaired DNA in time series after Cas9 activation reveals variable and often slow repair rates, with half-life times up to ∼10 hr. Furthermore, repair of the DSBs tends to be error prone. Both classical and microhomology-mediated end joining pathways contribute to the erroneous repair. Estimation of their individual rate constants indicates that the balance between these two pathways changes over time and can be altered by additional ionizing radiation. Our approach provides quantitative insights into DSB repair kinetics and fidelity in single loci and indicates that Cas9-induced DSBs are repaired in an unusual manner. [ABSTRACT FROM AUTHOR]

In this study, magnetic Fe 3 O 4 nanoparticles (NPs) were dispersed uniformly by varying the thickness of the SiO 2 coating, and their electronic and magnetic properties were investigated. X-ray diffraction confirmed the structural configuration of monophase inverse-spinel Fe 3 O 4 NPs in nanometer size. Scanning electron microscopy revealed the formation of proper nonporous crystallite particles with a clear core-shell structure with silica on the surface of Fe 3 O 4 NPs. The absorption mechanism studied through the zeta potential indicates that SiO 2 -coated Fe 3 O 4 nanocomposites (SiO 2 @Fe 3 O 4 NCs) possess electrostatic interactions to control their agglomeration in stabilizing suspensions by providing a protective shield of amorphous SiO 2 on the oxide surface. High-resolution transmission electron microscopy images demonstrate a spherical morphology having an average grain diameter of ∼11-17 nm with increasing thickness of SiO 2 coating with the addition of a quantitative presence and proportion of elements determined through elemental mapping and electron energy loss spectroscopy studies. Synchrotron-based element-specific soft X-ray absorption spectroscopy and X-ray magnetic circular dichroism (XMCD) techniques have been involved in the bulk-sensitive total fluorescence yield mode to understand the origin of magnetization in SiO 2 @Fe 3 O 4 NCs. The magnetization hysteresis of Fe 3 O 4 was determined by XMCD. At room temperature, the magnetic coercivity ( H c ) is as high as 1 T, which is about 2 times more than the value of the thin film and about 5 times more pronounced than that of NPs. For noninteracting single-domain NPs with the H c spread from 1 to 3 T, the Stoner-Wohlfarth model provided an intriguing explanation for the hysteresis curve. These curves determine the different components of Fe oxides present in the samples that derive the remnant magnetization involved in each oxidation state of Fe and clarify which Fe component is responsible for the resultant magnetism and magnetocrystalline anisotropy based on noninteracting single-domain particles.

Aim: To assess the current knowledge and practices in diabetic eye care and referral system regarding diabetic retinopathy (DR) in health centers of Islamabad and Rawal-Pindi., Methods: A cross-sectional study was carried out in 4 government and private health centers in Rawalpindi-Islamabad from May 2018 to Oct. 2018. A total of 38 Primary Care Physicians (general practitioners, family physicians, and internists) were recruited out of which data for 2 were either not returned, or were missing partially. Data were collected through a 27-item consented & validated, multiple-choice questionnaire based on physician characteristics, knowledge and practice of diabetic eye care and challenges faced due current DR referral system. Descriptive analyses for all variables were performed including, mean and standard deviation. Analytical analyses were also conducted to study association between different study variables., Results: Mean scores of knowledge for general practitioners, family physicians, and internists were 41.7%, 42.0% and 46.6% respectively. A lack of knowledge, and suboptimal practices were observed regarding signs, symptoms, screening, testing, evaluation and referral of DR regardless of physicians' specialty, or years in practice. Lack of expertise regarding direct ophthalmoscopy, interpretation of findings, and referral to an ophthalmologist were noted. Physicians who performed consultation and counselling according to patients' needs referred more patients to an ophthalmologist than those who restricted their consultation to a fixed amount of time and had more patients per unit time ( P =0.01). Physicians who had taken care of less than 5 number of patients with DR marked less incorrect answers with no significantly greater number or correct answers compared to physicians who had taken care of more than 5 number of patients with DR ( P =0.044). An association of more than 5 patients with DR taken care of with more need based patient consultation and counselling was also noted ( P =0.017). An evaluation of the current referral system for DR revealed major loopholes in the health care infrastructure, proper guidelines, properly functioning equipment, check and balances, and lack of guidance to physicians regarding acquiring and updating knowledge regarding DR., Conclusion: Lack of updated and adequate knowledge, practices among primary care physicians, and suboptimal diabetic eye care and referral system have contributed to late presentation of DR. Interventions are needed to improve current diabetic eye care, and knowledge and practices of primary care physicians., (International Journal of Ophthalmology Press.)