Political Economy of Fiscal Reforms in the 1990s

Throughout the decade of the 1990s, major emphasis in Pakistan remained on fiscal reform as a part of the reform programmes undertaken by the various governments of Pakistan. Fiscal reform assumes significance considering the high budget deficits that Pakistan has been experiencing. These have added to Pakistan’s total debt burden in general and external debt in particular. Increase in the burden of debt adds to debt-servicing expenditure which further feeds back into the issue of high fiscal deficit. Debt-servicing increased to almost 47 percent1 by the middle of the decade of 1990s and comprised 8.3 percent of the GDP, up from less than 1 percent mid-1960s. Pakistan’s external debt at over $32 billion2 in 1998 was 41 percent of its GNP which was amongst the highest in the South Asian region with India’s at 20 percent of GNP in the same year and Sri Lanka’s also at 41 percent3 of its GNP. In this paper, we attempt to explore the rationale behind the emphases on the improvement in both the deficit-to-GDP and the tax-to-GDP ratios that have remained the cornerstones of Pakistan’s fiscal reform effort in the decade of the 1990s. Section 2 is a discussion of the extent of successes and failures of the fiscal reform effort thus far and explores the relationship between tax generation and budget deficit. Section 3 discusses the impact of expenditures on budget deficit. Section 4 shows the rise in dependence on external sources of financing. Section 5 gives the conclusions.

Antenatal ultrasound diagnosis of congenital high airway obstruction syndrome: A case report and review of literature

Congenital high airway obstruction syndrome (CHAOS) is a rare life-threatening fetal condition resulting from obstruction of the upper fetal airway which may be partial or complete. Prenatal diagnosis is crucial as it usually results in stillbirth or death after delivery if unrecognized. We report a case of CHAOS that was diagnosed prenatally due to characteristic ultrasound features. We also briefly review literature in light of current management options

Influence of Acid Strength on Olefin Selectivity of Chabazite (CHA) Framework Zeolite/Zeotypes during Tandem CO2 Hydrogenation

The role of the Brønsted acid sites (BAS) strength of chabazite (CHA) framework on olefin selectivity during methanol-to-olefin (MTO) and tandem CO2 hydrogenation was investigated over an aluminosilicate, SSZ-13 and a silicoaluminophospate, SAPO-34 and their bifunctional admixtures with In2O3. During MTO, SSZ-13 and SAPO-34 yielded primarily olefins (cumulative selectivity of ~60% and ~90%, respectively at cumulative turn-over number, TON over 500). Interestingly, an interpellet admixture of In2O3/SSZ-13 (distance between redox sites and BAS of 260-900 µm)) predominantly yielded paraffins (cumulative selectivity of ~93% at cumulative TON over 40) via the secondary hydrogenation of olefins as seen from the cumulative paraffin-to-olefin (P/O) ratio of ~21 during CO2 hydrogenation. In comparison, an interpellet In2O3/SAPO-34 admixture yielded majority olefins (cumulative selectivity of ~67% at cumulative TON over 60) due to a lesser degree of secondary hydrogenation (cumulative P/O ratio of ~0.2) on the BAS in SAPO-34, which has a lower acid strength as compared to SSZ-13. Interestingly, both interpellet admixtures of In2O3/SSZ-13 and In2O3/SAPO-34 remained stable during tandem CO2 hydrogenation by favoring the olefin cycle and suppressing the formation of deactivation-inducing-aromatics, unlike MTO, where both admixtures showed fast deactivation. Ion-exchange of BAS (H+) with Inδ+ (from In2O3) in intrapellet admixtures (distance between redox sites and BAS of 270-1500 nm) of In2O3/SSZ-13, and In2O3/SAPO-34, inhibited C-C coupling and predominantly formed CH4. Overall, our study related to the product selectivity and deactivation in MTO and tandem CO2 hydrogenation over CHA framework zeolite/zeotype to the aromatic and olefin pool in the hydrocarbon pool mechanism. These underpinnings will help with rational catalyst design for tandem CO2 hydrogenation

Intermediate Transfer Rates and Solid-State Ion Exchange are Key Factors Determining the Bifunctionality of a Tandem CO2 Hydrogenation Catalyst

Probing the interaction between different active sites and transfer of reaction intermediates in bifunctional catalysts for tandem hydrogenation of CO2 is crucial for optimal catalyst design that maximize synergy to achieve high rates and product selectivity. Herein, thermocatalytic conversion of CO2 to hydrocarbon (HC) via a methanol (CH3OH) intermediate was investigated by modulating the placement of In2O3 and HZSM-5 in bifunctional admixtures at temperatures between 350 to 450 °C and 500 psig, to probe the key factors that drive synergy in these bifunctional systems. Analysis of the intermediate CH3OH transfer rates showed that although a millimeter scale placement of In2O3 and HZSM-5 yields a simple tandem reaction with a total HC and methanol CH3OH space-time yield of 8×10-6 molCgcat-1min-1, a microscale placement exhibits a ten-fold increase in catalytic activity with a total HC and CH3OH space-time yield of 8×10-5 molCgcat-1min-1 (at 400 °C) due to a faster advective and diffusive transfer rate of CH3OH. A combination of reactivity, spectroscopy with Raman, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD) patterns, microscopy with scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and control experiments on methanol to hydrocarbons (MTH) revealed that further enhancing the reaction intermediate transfer at a nanoscale placement was counteracted by solid-state ion exchange (SSIE) between Brønsted acid sites (H+) of the HZSM-5 with the Inδ+ ions from In2O3, and that the formation of CH4 at the nanoscale placement was likely through CH3OH hydrogenolysis and not CO2 methanation at these intimate distances. Overall, our data showed the interconnected and subtle ways through which bifunctionality of catalysts could be regulated and paves the way for the development of design principles for designing more effective bifunctional catalysts for tandem CO2 hydrogenation

Enabling the Circular Economy through Chemical Recycling and Upcycling of End-of-Use Plastics

Widespread plastic pollution has led to an environmental crisis, motivating new and effective methods for recycling and upcycling “end-of-use” plastics. In this review, we highlight recent advances in chemical recycling and upcycling pathways, namely, hydroconversion, pyrolysis, and solvent treatment for the deconstruction and valorization of post-consumer plastics. We highlight the advances in the design of supported metal catalysts (Pt, Ru, Zr), for the hydroconversion of plastics, especially polyolefins (PO) and polyesters. We deduce mechanistic insights by comparing and contrasting small alkane and PO hydroconversion reactions. We also review the two types of solvent treatments: chemical solvent treatment (solvolysis) for condensation polymers and solvent extraction for composite polymers. Further, we discuss advances in pyrolysis and cross alkane metathesis to deconstruct POs into liquid hydrocarbons, and finally, the functionalization of POs into vitrimers and adhesives. We highlight the challenges and envision the path forward in optimal catalyst and process design that will enable the development of chemical upcycling technologies for building a circular plastic economy

Stromal EGF and igf-I together modulate plasticity of disseminated triple-negative breast tumors

The causes for malignant progression of disseminated tumors and the reasons recurrence rates differ in women with different breast cancer subtypes are unknown. Here, we report novel mechanisms of tumor plasticity that are mandated by microenvironmental factors and show that recurrence rates are not strictly due to cell-intrinsic properties. Specifically, outgrowth of the same population of incipient tumors is accelerated in mice with triple-negative breast cancer (TNBC) relative to those with luminal breast cancer. Systemic signals provided by overt TNBCs cause the formation of a tumor-supportive microenvironment enriched for EGF and insulin-like growth factor-I (IGF-I) at distant indolent tumor sites. Bioavailability of EGF and IGF-I enhances the expression of transcription factors associated with pluripotency, proliferation, and epithelial-mesenchymal transition. Combinatorial therapy with EGF receptor and IGF-I receptor inhibitors prevents malignant progression. These results suggest that plasticity and recurrence rates can be dictated by host systemic factors and offer novel therapeutic potential for patients with TNBC

The Apcmin mouse has altered hematopoietic stem cell function and provides a model for MPD/MDS

Apc, a negative regulator of the canonical Wnt signaling pathway, is a bona-fide tumor suppressor whose loss of function results in intestinal polyposis. APC is located in a commonly deleted region on human chromosome 5q, associated with myelodysplastic syndrome (MDS), suggesting that haploinsufficiency of APC contributes to the MDS phenotype. Analysis of the hematopoietic system of mice with the Apcmin allele that results in a premature stop codon and loss of function showed no abnormality in steady state hematopoiesis. Bone marrow derived from Apcmin mice showed enhanced repopulation potential, indicating a cell intrinsic gain of function in the long-term hematopoietic stem cell (HSC) population. However, Apcmin bone marrow was unable to repopulate secondary recipients because of loss of the quiescent HSC population. Apcmin mice developed a MDS/myeloproliferative phenotype. Our data indicate that Wnt activation through haploinsufficiency of Apc causes insidious loss of HSC function that is only evident in serial transplantation strategies. These data provide a cautionary note for HSC-expansion strategies through Wnt pathway activation, provide evidence that cell extrinsic factors can contribute to the development of myeloid disease, and indicate that loss of function of APC may contribute to the phenotype observed in patients with MDS and del(5q)

Physiological Jak2V617F expression causes a lethal myeloproliferative neoplasm with differential effects on hematopoietis stem and progenitor cells

We report a Jak2V617F knockin mouse myeloproliferative neoplasm (MPN) model resembling human polycythemia vera (PV). The MPN is serially transplantable and we demonstrate that the hematopoietic stem cell (HSC) compartment has the unique capacity for disease initiation but does not have a significant selective competitive advantage over wild-type HSCs. In contrast, myeloid progenitor populations are expanded and skewed toward the erythroid lineage, but cannot transplant the disease. Treatment with a JAK2 kinase inhibitor ameliorated the MPN phenotype, but did not eliminate the disease-initiating population. These findings provide insights into the consequences of JAK2 activation on HSC differentiation and function and have the potential to inform therapeutic approaches to JAK2V617F-positive MPN

Musashi-2 regulates normal hematopoiesis and promotes aggressive myeloid leukemia

RNA-binding proteins of the Musashi (Msi) family are expressed in stem cell compartments and in aggressive tumors, but they have not yet been widely explored in the blood. Here we demonstrate that Msi2 is the predominant form expressed in hematopoietic stem cells (HSCs), and its knockdown leads to reduced engraftment and depletion of HSCs in vivo. Overexpression of human MSI2 in a mouse model increases HSC cell cycle progression and cooperates with the chronic myeloid leukemia-associated BCR-ABL1 oncoprotein to induce an aggressive leukemia. MSI2 is overexpressed in human myeloid leukemia cell lines, and its depletion leads to decreased proliferation and increased apoptosis. Expression levels in human myeloid leukemia directly correlate with decreased survival in patients with the disease, thereby defining MSI2 expression as a new prognostic marker and as a new target for therapy in acute myeloid leukemia (AML)