Size Shrinkage Research Articles

Co-assembly of polymeric conjugates sensitizes neoadjuvant chemotherapy of triple-negative breast cancer with reduced systemic toxicity

Rational design of polymeric conjugates could greatly potentiate the combination therapy of solid tumors. In this study, we designed and prepared two polymeric conjugates (HT-DTX and PEG-YC-1), whereas the drugs were attached to the PEG via a linker sensitive to cathepsin B, over-expressed in TNBC. Stable nanostructures were formed by these two polymer prodrug conjugates co-assembly (PPCC). The stimuli-responsiveness of PPCC was confirmed, and the size shrinkage under tumor microenvironment would facilitate the penetration of PPCC into tumor tissue. In vitro experiments revealed the molecular mechanism for the synergistic effect of the combination of DTX and YC-1. Moreover, the systemic side effects were significantly diminished since the biodistribution of PPCC was improved after i.v. administration in vivo. In this context, the co-assembled nano-structural approach could be employed for delivering therapeutic drugs with different mechanisms of action to exert a synergistic anti-tumor effect against solid tumors, including triple-negative breast cancer. Statement of significance•Co-assembly of polymeric prodrug conjugates could form stable and homogeneous nanostructures, improving cellular uptake by cancer cells and in vivo tumor penetration and retention.•Co-delivery of neoadjuvant therapeutic drug (DTX) and HIF-1α inhibitor (YC-1) synergizes the anti-tumor effect by affecting HIF-1α expression and G2/M phase arrest.•Polymer prodrug conjugates co-assembly (PPCC) could reverse tumor resistance to neoadjuvant therapy, retard tumor progression, and prevent lung metastasis with reduced systemic toxicity in a murine triple-negative breast cancer model.

PH/redox responsive size‐switchable intelligent nanovehicle for tumor microenvironment targeted DOX release

Tumor microenvironment (TME) targeted strategy could control the drug release in tumor cells more accurately and creates a new opportunity for enhanced site-specific targeted delivery. In this study, (PAA-b-PCL-S-S-PCL-b-PAA) copolymeric nanoparticles (NPs) with size-switchable ability and dual pH/redox-triggered drug release behavior were designed to significantly promote cancer uptake (cell internalization of around 100% at 30 min) and site-specific targeted doxorubicin (DOX) delivery in MDA-MB-231 tumor cells. NPs surface charge was shifted from − 17.8 to − 2.4 and their size shrunk from 170.3 to 93 nm in TME. The cell cycle results showed that DOX-loaded NPs showed G2/M (68%) arrest, while free DOX showed sub-G1 arrest (22%). Apoptosis tests confirmed that the cells treated with DOX-loaded NPs showed a higher amount of apoptosis (71.6%) than the free DOX (49.8%). Western blot and RT-PCR assays revealed that the apoptotic genes and protein levels were significantly upregulated using the DOX-loaded NPs vs. the free DOX (Pvalue < 0.001). In conclusion, dual pH/redox-responsive and size-switchable DOX-loaded NPs developed here showed outstanding anti-tumoral features compared with free DOX that might present a prospective platform for tumor site-specific accumulation and drug release that suggest further in vivo research.

Bruceine A inhibited breast cancer proliferation and metastasis by inducing autophagy via targeting PI3K-AKT signaling pathway.

Although there have been significant advances in cancer treatment, the urgent need to inhibit breast cancer metastasis remained unmet. Bruceine A (BA) is a natural compound extracted from Bruceae Fructus and has long been recognized to have antitumor effects with high safety and biocompatibility. However, the mechanisms and/or targets of BA for metastatic breast cancer treatment are still not fully elucidated. In this study, we systematically investigated the effects of BA on inhibition of breast cancer metastasis and its underlying mechanisms. We found that, in addition to its cytotoxic effects, BA significantly inhibited the invasion and migration capabilities of two types of breast cancer cell lines (MDA-MB-231 and MCF-7) while concurrently promoting apoptosis in these cells. Further mechanistic studies revealed that, by targeting the canonical PI3K-AKT signaling pathway, BA initiated autophagy of both types of breast cancer cell lines invitro. Invivo results further confirmed the invitro findings, manifested by shrinkage of size and weight of breast tumor as well as initiation of autophagy (indicated by upregulation of LC3I/II) through targeting PI3K-AKT pathway on mice model. These data collectively demonstrated the potential of BA in antimetastasis of breast cancer cells, suggesting its future clinical transformation in metastatic breast cancer therapy.

Long-term benefit of sotorasib in patients with KRAS G12C-mutated non-small-cell lung cancer: plain language summary.

This is a plain language summary of a study called CodeBreaK 100. The CodeBreaK 100 study included patients with non-small-cell lung cancer that had spread outside the lung (advanced). Lung cancer is one of the most common forms of cancer. CodeBreaK 100 specifically looked at patients with a particular change(mutation) in the KRAS gene resulting in the mutated protein called KRAS G12C. The KRAS G12C mutation can lead to development and growth of lung cancer. Patients received a treatment called sotorasib, which has accelerated approval or full approval in over 50 countries for patients with non-small-cell lung cancer with the KRAS G12C mutation. The CodeBreaK 100 study looked at whether sotorasib is a safe and effective treatment for advanced non-small-cell lung cancer. Sotorasib is designed to specifically target and lock the mutated KRAS protein in the inactive state to treat non-small-cell lung cancer. In total, 174 adults were treated with sotorasib. Treatment-related side effects were seen in 70% of patients and were severe in 21% of patients. The most common side effects included diarrhea, increased liver enzymes, nausea and tiredness. 70 (41%) patients responded to sotorasib and 144 (84%) patients had tumors that either remained stable or shrunk in size. 29 (41%) patients who responded to sotorasib responded for over 12months. After 2years, 9 patients with a response remained on sotorasib; there were no notable increases in tumor size or development of new tumors over this time. There were 5patients who received sotorasib for more than 2years and continued to respond. Long-term benefit was seen for some patients. Patients also benefitted from treatment when the tumor expressed different amounts of a protein called PD-L1.In total, 33% of patients were still alive after 2years. Results show the long-term benefit of sotorasib therapy for people with advanced KRAS G12C-mutated non-small-cell lung cancer. Clinical Trial Registration: NCT03600883 (CodeBreaK 100) (ClinicalTrials.gov).

Preparation of Pleurotus eryngii protein baked food by 3D printing

Studying the structural stability and quality changes of 3D printed food in the post-processing process is an important aspect to promote the popularization and application of 3D printing technology. Pleurotus eryngii protein (PEP) and potato whole powder (PWP) were used as raw materials in this work to investigate the effect of internal structure and processing time on 3D printed samples, and baking was used as a post-processing method. The results indicated that the 3D printing ink with 20% PEP presented suitable viscosity, fluidity, and mechanical strength, ensuring the best 3D printing performance. The 3D-printed samples with 95% fill ratio demonstrated minimal weight loss and size shrinkage till 30 min of baking, compared with mould samples, highlighting the superior product appearance preservation and production advantages of 3D printing technology in baked food. As the baking time increased, the color of the baked food was darker, while the hardness of the upper and lower surfaces and moisture binding force increased, and internal softness decreased. Optimal results were achieved after baking for 20 min at an upper temperature of 150 °C and a lower temperature of 120 °C, resulting in the highest sensory quality score of 81.67 out of 100. This research prepared PEP-PWP printed food that was resistant to post-treatment collapse to a greater extent, which shed new light on the development of healthy and aesthetically pleasing baked foods.

The Scorpionfly (Panorpa cognata) Genome Highlights Conserved and Derived Features of the Peculiar Dipteran X Chromosome.

Many insects carry an ancient X chromosome-the Drosophila Muller element F-that likely predates their origin. Interestingly, the X has undergone turnover in multiple fly species (Diptera) after being conserved for more than 450 My. The long evolutionary distance between Diptera and other sequenced insect clades makes it difficult to infer what could have contributed to this sudden increase in rate of turnover. Here, we produce the first genome and transcriptome of a long overlooked sister-order to Diptera: Mecoptera. We compare the scorpionfly Panorpa cognata X-chromosome gene content, expression, and structure to that of several dipteran species as well as more distantly related insect orders (Orthoptera and Blattodea). We find high conservation of gene content between the mecopteran X and the dipteran Muller F element, as well as several shared biological features, such as the presence of dosage compensation and a low amount of genetic diversity, consistent with a low recombination rate. However, the 2 homologous X chromosomes differ strikingly in their size and number of genes they carry. Our results therefore support a common ancestry of the mecopteran and ancestral dipteran X chromosomes, and suggest that Muller element F shrank in size and gene content after the split of Diptera and Mecoptera, which may have contributed to its turnover in dipteran insects.

Bridging responses to a human telomerase reverse transcriptase-based peptide cancer vaccine candidate in a mechanism-based model

Therapeutic cancer vaccines are novel immuno-therapeutics, aiming to improve clinical outcomes with other immunotherapies. However, obstacles to their successful clinical development remain, which model-informed drug development approaches may address. UV1 is a telomerase based therapeutic cancer vaccine candidate being investigated in phase I clinical trials for multiple indications. We developed a mechanism-based model structure, using a nonlinear mixed‐effects modeling techniques, based on longitudinal tumor sizes (sum of the longest diameters, SLD), UV1-specific immunological assessment (stimulation index, SI) and overall survival (OS) data obtained from a UV1 phase I trial including non-small cell lung cancer (NSCLC) patients and a phase I/IIa trial including malignant melanoma (MM) patients. The final structure comprised a mechanistic tumor growth dynamics (TGD) model, a model describing the probability of observing a UV1-specific immune response (SI ≥ 3) and a time-to-event model for OS. The mechanistic TGD model accounted for the interplay between the vaccine peptides, immune system and tumor. The model-predicted UV1-specific effector CD4+ T cells induced tumor shrinkage with half-lives of 103 and 154 days in NSCLC and MM patients, respectively. The probability of observing a UV1-specific immune response was mainly driven by the model-predicted UV1-specific effector and memory CD4+ T cells. A high baseline SLD and a high relative increase from nadir were identified as main predictors for a reduced OS in NSCLC and MM patients, respectively. Our model predictions highlighted that additional maintenance doses, i.e. UV1 administration for longer periods, may result in more sustained tumor size shrinkage.

Organized Crime and Firms: Evidence from Antimafia Enforcement Actions

We exploit staggered municipality-level antimafia enforcement actions in Italy over the 1995–2015 period to study how the presence of organized crime affects firms. Following enforcement actions, we find increases in competition (i) among firms and (ii) for public procurement contracts. Firms that do not exit after a weakening of organized crime shrink in size, more so when operating in the nontradable sector. Our findings are consistent with organized crime acting as a barrier to entry and affecting local economic activity. This paper was accepted by David Sraer, finance. Supplemental Material: Data and the online appendix are available at https://doi.org/10.1287/mnsc.2021.00859 .

Codelivery of CuS and DOX into Deep Tumors with Size and Charge-Switchable PAMAM Dendrimers for Chemo-photothermal Therapy.

Accurate targeting of therapeutic agents to specific tumor tissues, especially via deep tumor penetration, has been an effective strategy in cancer treatments. Here, we described a flexible nanoplatform, pH-responsive zwitterionic acylsulfonamide betaine-functionalized fourth-generation PAMAM dendrimers (G4-AB), which presented multiple advantages for chemo-photothermal therapy, including template synthesis of ultrasmall copper sulfide (CuS) nanoparticles and further encapsulation of doxorubicin (DOX) (G4-AB-DOX/CuS), long-circulating performance by a relatively large size and zwitterionic surface in a physiological environment, combined size shrinkage, and charge conversions via pH-responsive behavior in an acidic tumor microenvironment (TME). Accordingly, high tumor penetration and positive cell uptake for CuS and DOX have been determined, which triggered an excellent combination treatment under near-infrared irradiation in comparison to the monochemotherapy system and irresponsive chemo-photothermal system. Our study represented great promise in constructing multifunctional carriers for the effective delivery of photothermal nanoparticles and drugs in chemo-photothermal therapy.

A Link between Prenatal Stage of Life during the Great Chinese Famine and Subsequent Depressive Symptoms among Middle-Aged and Older Adults

Prenatal malnutrition may increase the risk of depressive symptoms in adulthood. This study investigated the association between prenatal exposure to malnutrition with risk of depressive symptoms in middle-aged and older adults using the Chinese Great Famine of 1959–1961 as a natural experiment. Data were obtained from the China Health and Retirement Longitudinal Study baseline survey (2011). A total of 5391 individuals born from 1956 to 1965 were included in the study. Depressive symptoms were ascertained via the Center for Epidemiological Studies Depression Scale short form. Famine severity was measured using the cohort size shrinkage index. Difference-in-differences models were used to explore the association between prenatal famine exposure and later-life depressive symptoms. Compared with the post-famine cohort (1963–1965), famine cohorts (1959–1962) were 4.74 times (95% CI = 1.28–8.20) as likely to develop depressive symptoms. The stratified analysis found that prenatal exposure to famine was associated with depressive symptoms in rural residents but not those living in urban areas. In rural females, prenatal malnutrition was associated with a higher risk of depressive symptoms. However, there was no significant association between prenatal malnutrition and depressive symptoms in rural males. Our results indicated that prenatal malnutrition may contribute to a higher risk for depressive symptoms in later life among female rural residents.

Molecular dynamics and experiment on ultraviolet-thermal curing abrasive tools for polishing microstructures

To achieve efficient polishing of the microstructure array, a preparation method of the UV-thermal curing abrasive tools with diamond was proposed. The properties of the UV-thermal curing system were studied using molecular dynamics (MD) and experiments. The time, frequency, and pressure parameters of the UV-thermal curing abrasive tool were optimized by polishing the copper plate. MD simulation results show that increasing the temperature to 340 K can improve the blending compatibility. With the increase of the bisphenol A acrylate, the tensile property enhances from 16.38 MPa to 42.98 MPa, and the size shrinkage and mass loss weaken. The addition of diamond particles improves the anti-friction coefficient. Finally, the microstructure is polished twice under the polishing pressure of 300 N and 200 N, resulting in a roughness of Ra61nm on the upper surface and Ra105nm on the lower surface. This study can be used to guide the preparation and application of UV-thermal curing abrasive tools for polishing microstructure.

FRI322 Lack Of Tumor Size Change With Long-term Cabergoline For Prolactinoma

Abstract Disclosure: S. Bendaram: None. V. Kantorovich: None. Introduction: Prolactinomas are the most common tumors of the pituitary gland and account for about 40% of all Pituitary adenomas, of which 10% are macroprolactinomas measuring &amp;gt;1 cm. Dopamine Agonists (DAs) normalize the prolactin levels and aid in shrinkage of the tumor size. We present two cases of Macroprolactinomas with biochemical response to DAs but no shrinkage in size as expected. Case 1: 75-year-old male with history of hypertension, left frontal MCA stroke with residual aphasia who underwent brain MRI for a recent TIA, was found to have a new 2.3 x 1.9 x 2.4 cm mass in the pituitary fossa invading the right cavernous sinus, concerning for a pituitary macroadenoma. Prolactin levels were 4152 ng/ml on dilution study, low testosterone with inappropriately normal LH/FSH. He denied any symptoms from compression, hyperprolactinemia or hypogonadism. After starting Cabergoline 0.25 mg biweekly, repeat levels in 2 weeks showed a decline in prolactin levels to 808.7 ng/ml. Visual Field (VF) testing was abnormal but was unreliable due to high fixation losses. Same dose of cabergoline was continued, with decline in prolactin further to 37.8 ng/ml, while a repeat MRI Brain showed no substantial change in the size of the mass. Cabergoline was doubled, and a repeat MRI still demonstrated same size of the mass, despite prolactin levels decreasing to below normal range. Case 2: 62-year-old male with history of macroprolactinoma for &amp;gt;3 years, but non-adherent to medications, who presented to his PCP with persistent occipital headaches, and was referred to Endocrinology due to repeat MRI brain revealing interval increase in the size of sellar and suprasellar mass measuring 2.2 x 2.2 x 2.9 cm in size consistent with macroadenoma with mass-effect on the optic chiasm and prechiasmatic optic nerves. Evaluation of pituitary panel revealed prolactin levels of 1352 ng/ml, low testosterone and LH, while the rest of the labs were normal. He was started on cabergoline 0.5 mg biweekly, and a repeat prolactin level after a single dose of cabergoline improved to 469 ng/ml. He was continued on the same dose with prolactin dropping to 2.6 ng/ml in 2 months, and further to 1.8 ng/dl after 10 months of treatment. Initial VF testing also demonstrated some degree of defect with compression of optic chiasm. Repeat MRI 3 months after initiation of cabergoline revealed interval decrease in size of macroadenoma to 2.1 cm in the largest dimension, which stayed the same on the recent imaging. Discussion: DAs like Cabergoline are first line therapy for prolactinomas. Fibrotic changes from long standing adenomas might be a possibility causing resistance to shrinkage of tumor, however it would be interesting to know if any specific molecular mechanisms that could be involved. In tumors with significant mass effect or those not responding to MT, Surgery is the preferred next step, and neurosurgery evaluation is necessary for further management. Presentation: Friday, June 16, 2023

THU025 Acromegaly And Central Hyperthyroidism

Abstract Disclosure: A. Akhtar: None. M.A. Mahmood: None. Introduction: Pituitary adenomas are usually benign neoplasms that are the third most common type of central nervous system tumors. Although TSH releasing tumor accounts for 1% of pituitary adenomas, about one-third of the time it co-secretes Growth Hormone. Co-secretion of TSH and GH can further promote the prognosis of the tumor, therefore, must be immediately treated medically or surgically. Case Report: The case is of a 42 years old male patient who presented to his orthodontist with the complaint of loosening teeth and was referred to a primary care physician. According to the patient, he has observed an increase in his ring size up to 3 times his usual size, one and a half increase in his shoe size, some degree of joint pain, occasional visual blurriness, no weight loss, and snoring. He has no history of headaches, breast tenderness, or discharge. He works at a farm and has no family history of pituitary tumors. His laboratory findings in May 2021 show IGF-1 1028 ng/mL (normal less than 278 ng/mL), ACTH 72.2 pg/mL (normal &amp;lt;60pg/mL), Prolactin, TSH, LH and FSH levels were normal. These findings suggested an IGF-producing pituitary adenoma. During further workup, he had high levels of free T4 and free T3, 2.7 ng/dL and 8.2pg/mL (Normal 2.3 - 4.2pg/mL), respectively, along with elevated TSH levels, which were 8.1mIU/L (normal 0.27-4.2mIU/L). Magnetic resonance imaging showed a pituitary mass of 1.8cm x 2.0cm x 1.6cm in the suprasellar region, abutting the optic chiasm, and showed heterogeneous enhancement. There were no signs of hemorrhage. His visual field examinations were normal. He was prescribed to take 50mg of octreotide every 8 hours. In six weeks, the patient had improved levels of serum TSH which was lowered to 0.785mIU/L, and free T4 and free T3, which were 1.62pmol/L and 3.45pmol/L, respectively. He had transsphenoidal pituitary surgery. Pathology showed a 2.6 x 2.0 x 0.3 cm tumor of somatotropic type. Post-surgery MRI showed no tumor residues. Discussion: We report a middle-aged man with a rare case of the pituitary tumor with acromegaly and central hyperthyroidism. Thyrotropinomas, also known as TSHomas, are benign pituitary adenoma that produces thyroid stimulating hormones. Although rare, they are macroadenomas 80% of the times and 20-25% of the time co-secrete other pituitary hormones. These tumors may show elevated fT3, fT4, and TSH, and increased alpha-subunit. There is not enough evidence to proof the exact origin of the pathology, however, immunohistologically, the tumor cells arise from PIT1-lineage adenohypophyseal cells and could be associated with MEN 1 mutation on chromosome 11q13. Surgical removal of the tumor is a preferred approach to TSHomas, but recent studies have shown a significant improvement with medial therapy of somatostatin analogs by interacting with somatostatin receptors. Octreotide, a somatostatin analog has been clinically shown to bring the thyroid hormones to a normal level in 80% if cases and shrinkage of tumor size in pituitary adenoma in 60% of cases. It can be used as a pre-operative therapy to reduce the levels of free thyrotropin. It also reduces GH and serum IGF-1 levels. Co-secretion of TSH and GH promotes the prognosis of tumors which may be prevented with early diagnosis and treatment. Presentation: Thursday, June 15, 2023

Heat transfer enhancement of the ultra-thin flat heat pipe integrated with copper-fiber bundle wicks

The rapid size shrinkage and the increasing power of the chip made it increasingly challenging to dissipate the heat generated by electronics. Ultra-thin flat heat pipes possessed the characteristics of high thermal conductivity, slender shape, and absence of moving parts, making them an effective solution for heat dissipation in small spaces. In this paper, the composite wicks made by copper-fiber bundle were designed and fabricated. The heat transfer performance of the ultra-thin heat pipe was experimentally investigated with a focus on the effects of wick design. The weaving method used in the composited wick affected the thermal performance of the ultra-thin heat pipe. The results indicated that the wicks with heterostructure increased the maximum heat transfer capacity by 6 W when compared with the homogeneous structures. The single-layer copper mesh design resulted in a 13 W increase in maximum heat transfer capacity compared to the double-layer design.

Density-dependent relativistic mean field approach and its application to single-Λ hypernuclei in oxygen hyperisotopes* *Supported by the Fundamental Research Funds for the Central Universities, Lanzhou University (lzujbky-2022-sp02, lzujbky-2023-stlt01), the National Natural Science Foundation of China (11875152, 12275111), and the Strategic Priority Research Program of Chinese Academy of Sciences (XDB34000000)

The in-medium feature of nuclear force, which includes both nucleon-nucleon () and hyperon-nucleon () interactions, impacts the description of single-Λ hypernuclei. With the alternated mass number or isospin of hypernuclei, such effects may be unveiled by analyzing the systematic evolution of the bulk and single-particle properties. From a density-dependent meson-nucleon/hyperon coupling perspective, a new effective interaction in the covariant density functional (CDF) theory, namely, DD-LZ1-, is obtained by fitting the experimental data of Λ separation energies for several single-Λ hypernuclei. It is then used to study the structure and transition properties of single-Λ hypernuclei in oxygen hyperisotopes, in comparison with those determined using several selected CDF Lagrangians. A discrepancy is explicitly observed in the isospin evolution of spin-orbit splitting with various effective interactions, which is attributed to the divergence of the meson-hyperon coupling strengths with increasing density. In particular, the density-dependent CDFs introduce an extra contribution to reduce the value but enhance the isospin dependence of the splitting, which originates from the rearrangement terms of Λ self-energies. In addition, the characteristics of hypernuclear radii are studied along the isotopic chain. Owing to the impurity effect of the Λ hyperon, a size shrinkage is observed in the matter radii of hypernuclei compared with the cores of normal nuclei, and its magnitude is further elucidated to correlate with the incompressibility of nuclear matter. Moreover, there is a sizable model-dependent trend in which the Λ hyperon radii evolve with neutron number, which is decided partly by the in-medium interactions and core polarization effects.

The validation of online webcam-based eye-tracking: The replication of the cascade effect, the novelty preference, and the visual world paradigm.

The many benefits of online research and the recent emergence of open-source eye-tracking libraries have sparked an interest in transferring time-consuming and expensive eye-tracking studies from the lab to the web. In the current study, we validate online webcam-based eye-tracking by conceptually replicating three robust eye-tracking studies (the cascade effect, n = 134, the novelty preference, n = 45, and the visual world paradigm, n = 32) online using the participant's webcam as eye-tracker with the WebGazer.js library. We successfully replicated all three effects, although the effect sizes of all three studies shrank by 20-27%. The visual world paradigm was conducted both online and in the lab, using the same participants and a standard laboratory eye-tracker. The results showed that replication per se could not fully account for the effect size shrinkage, but that the shrinkage was also due to the use of online webcam-based eye-tracking, which is noisier. In conclusion, we argue that eye-tracking studies with relatively large effects that do not require extremely high precision (e.g., studies with four or fewer large regions of interest) can be done online using the participant's webcam. We also make recommendations for how the quality of online webcam-based eye-tracking could be improved.

Linear phased meta-material incorporated patch antenna array at sub-6 GHz for 5G base stations

ABSTRACT This article presented a four-element dual-band linear phased antenna array operating at sub-6 GHz. The single-element antenna was designed by mounting a double-negative single- layered Complementary Split Ring Resonator (SL-CSRR) on the patch and grounding with a rectangular slot and four SL-CSRR’s array; it was resonated at dual bands 3.43–3.56 GHz and 4.93–5.75 GHz and got size shrinkage of 80.45% with dimensions 0.35λx0.35λx0.028λ mm3. The proposed phased array antenna was resonated in 3.42–3.57 GHz and 4.86–5.74 GHz with central frequencies 3.49 GHz and 5.18 GHz, respectively, with respect to −10 dB impedance bandwidth. It was dimensioned with 0.35λx2.42λx0.028λ mm3. The isolation of > 16 dB, ECC < 0.1, DG ~ 10 dB, CCL < 0.15bits/s/Hz and MEG<-6 dB were achieved. The maximum gain of 8.4dBi and 10.4dBi and maximum efficiency of 81.14%, and 99.12% were achieved over the two resonated bands, respectively. The array antenna excited initially with 0° phase difference was radiated bi-directional beam focused to 0° and 180° in the pattern like a broadside array and with the change of phase difference, the structure capable to focus the beam to ± 90° like end-fire array at 3.49 GHz and it was capable to steer the beam to ± 48.6° at 5.18 GHz. These results demonstrated that the proposed phased array antenna is a good candidate to provide services at base stations for 5 G sub-6 GHz applications. The prototypes of the single-element antenna and four-element phased array antennae were fabricated and tested. The matching of simulation results with measurement one has a good commitment to similarity.

Effect of Differently Shaped Solder Joints of Chip Resistor on Fatigue Life

Abstract As surface mount components shrink in size, smaller apertures on stencils during solder paste printing can lead to uneven solder volume on a single resistor. This can result in the formation of irregular solder shapes, which are often deemed acceptable criterion depending on assembly house. However, such irregularities can potentially introduce variations in the fatigue life of the surface mount component. This study employs experimental and numerical approaches to investigate the reliability of differently shaped SAC305 solder joints on a single chip resistor. Four distinct solder shapes, concave, straight, tiny convex, and convex, are generated using varying volumes of solder paste controlled by uniquely designed apertures on a stencil. Eight pairs of differently shaped solder joints are assembled to hold a chip resistor in place. The test assembly involves R1005 and R0402 soldered with SAC305 and undergoes thermal shock cycling. As a single chip resistor assembly consists of two solder joints connecting termination and pads, the effect of solder volume difference between two solder joints are investigated. The fatigue life corresponds to decrease as the solder volume difference increase as 40%, 80%, and 120%. Conversely, total volume of two solder joints in a single chip resistor increases in scenarios with the same volume difference between two solder joints. Experimental data and finite element analysis lead to a new set of Darveaux's constants specific to this assembly. This study provides guideline to control the solder paste volumes in relation to fatigue life and enables numerical solution using a new Darveaux's constants.

Advances in Analytical Techniques and Applications in Exploration, Mining, Extraction, and Metallurgical Studies of Rare Earth Elements

The use of analytical techniques is important and critical in all areas related to REE, such as basic fundamental research, exploration, mining, extraction, and metallurgical activities at different stages by different industries. At every stage of these activities, rock, ore, minerals, and other related materials have to be analyzed for their REE contents in terms of elemental, isotopic, and mineralogical concentrations using different analytical techniques. Spectacular developments have taken place in the area of analytical instrumentation during the last four decades, with some of them having shrunk in size and become handheld. Among laboratory-based techniques, F-AAS, GF-AAS, ICP-OES, and MP-AES have become very popular. Because of high sensitivity, fewer interference effects, and ease of use, ICP-MS techniques, such as quadrupole ICP-MS, ICP-MS/MS, ICP-TOF-MS, MH-ICP-MS, HR-ICP-MS, and MC-ICP-MS, with both solution nebulization as well as direct solid analysis using laser ablation sample introduction methods, have become more popular for REE analysis. For direct analysis of solids, INAA, XRF, and LIBS techniques, as well as LA-based ICP-MS techniques, are being extensively utilized. The LIBS technique in particular requires little to no sample preparation. TIMS, SIMS, and SHRIMP techniques are being used for isotopic as well as dating REE depots. Portable analytical techniques, such as pXRF, pLIBS, and Raman spectrometers are able to perform in situ analysis even in the field, helping to make fast decisions during exploration studies. At present, hyperspectral remote sensing techniques including handheld, drone, and satellite-based techniques have become very popular in REE exploration studies because of their ability to cover larger areas in a limited time and, thus, became very cost-effective. Deployment of microanalytical devices/sensors mounted in remotely operated vehicles (ROV) is being successfully utilized in detecting REE-rich deposits in the deep oceans. Providing updated in-depth information on all these important aspects with suitable examples, especially from the point of view of REE research studies is the focal point of this review article.

A General Layout Pattern Clustering Using Geometric Matching Based Clip Relocation and Lower-Bound Aided Optimization

With the continuous shrinking of feature size, detection of lithography hotspots has been raised as one of the major concerns in Design-for-Manufacturability (DFM) of semiconductor processing. Hotspot detection, along with other DFM measures, trades off turn-around time for the yield of IC manufacturing, thus a simplified but wide-range-covered pattern definition is a key essential to the problem. Layout pattern clustering methods, which group geometrically similar layout clips into clusters, have been vastly proposed to identify layout patterns efficiently. To minimize the clustering number for subsequent DFM processing, in this paper, we propose a geometric-matching-based clip relocation technique to increase the opportunity of pattern clustering. Particularly, we formulate the lower-bound of the clustering number as a maximum-clique problem, and we have also proved that the clustering problem can be solved by the result of the maximum-clique very efficiently. Compared with the experimental results of the state-of-the-art approaches on ICCAD 2016 Contest benchmarks, the proposed method can achieve the optimal solutions for all benchmarks with very competitive run-time. To evaluate the scalability, the ICCAD 2016 Contest benchmarks are extended and evaluated. And experimental results on the extended benchmarks demonstrate that our method can reduce the cluster number by 16.59% on average, while the run-time is 74.11% faster on large-scale benchmarks compared with previous works.